Spinal cord injury is a disabling condition with limited treatment options.Multiple studies have provided evidence suggesting that small extracellular vesicles(SEVs)secreted by bone marrow mesenchymal stem cells(MSCs)...Spinal cord injury is a disabling condition with limited treatment options.Multiple studies have provided evidence suggesting that small extracellular vesicles(SEVs)secreted by bone marrow mesenchymal stem cells(MSCs)help mediate the beneficial effects conferred by MSC transplantation following spinal cord injury.Strikingly,hypoxia-preconditioned bone marrow mesenchymal stem cell-derived SEVs(HSEVs)exhibit increased therapeutic potency.We thus explored the role of HSEVs in macrophage immune regulation after spinal cord injury in rats and their significance in spinal cord repair.SEVs or HSEVs were isolated from bone marrow MSC supernatants by density gradient ultracentrifugation.HSEV administration to rats via tail vein injection after spinal cord injury reduced the lesion area and attenuated spinal cord inflammation.HSEVs regulate macrophage polarization towards the M2 phenotype in vivo and in vitro.Micro RNA sequencing and bioinformatics analyses of SEVs and HSEVs revealed that mi R-146a-5p is a potent mediator of macrophage polarization that targets interleukin-1 receptor-associated kinase 1.Reducing mi R-146a-5p expression in HSEVs partially attenuated macrophage polarization.Our data suggest that HSEVs attenuate spinal cord inflammation and injury in rats by transporting mi R-146a-5p,which alters macrophage polarization.This study provides new insights into the application of HSEVs as a therapeutic tool for spinal cord injury.展开更多
Exosomes derived from human bone marrow mesenchymal stem cells(MSC-Exo)are characterized by easy expansion and storage,low risk of tumor formation,low immunogenicity,and anti-inflammatory effects.The therapeutic effec...Exosomes derived from human bone marrow mesenchymal stem cells(MSC-Exo)are characterized by easy expansion and storage,low risk of tumor formation,low immunogenicity,and anti-inflammatory effects.The therapeutic effects of MSC-Exo on ischemic stroke have been widely explored.However,the underlying mechanism remains unclear.In this study,we established a mouse model of ischemic brain injury induced by occlusion of the middle cerebral artery using the thread bolt method and injected MSC-Exo into the tail vein.We found that administration of MSC-Exo reduced the volume of cerebral infarction in the ischemic brain injury mouse model,increased the levels of interleukin-33(IL-33)and suppression of tumorigenicity 2 receptor(ST2)in the penumbra of cerebral infarction,and improved neurological function.In vitro results showed that astrocyte-conditioned medium of cells deprived of both oxygen and glucose,to simulate ischemia conditions,combined with MSC-Exo increased the survival rate of primary cortical neurons.However,after transfection by IL-33 siRNA or ST2 siRNA,the survival rate of primary cortical neurons was markedly decreased.These results indicated that MSC-Exo inhibited neuronal death induced by oxygen and glucose deprivation through the IL-33/ST2 signaling pathway in astrocytes.These findings suggest that MSC-Exo may reduce ischemia-induced brain injury through regulating the IL-33/ST2 signaling pathway.Therefore,MSC-Exo may be a potential therapeutic method for ischemic stroke.展开更多
Our previous studies showed that miR-23b was downregulated in patients with intracerebral hemorrhage(ICH). This indicates that miR-23b may be closely related to the patho-physiological mechanism of ICH, but this hypot...Our previous studies showed that miR-23b was downregulated in patients with intracerebral hemorrhage(ICH). This indicates that miR-23b may be closely related to the patho-physiological mechanism of ICH, but this hypothesis lacks direct evidence. In this study, we established rat models of ICH by injecting collagenase Ⅶ into the right basal ganglia and treating them with an injection of bone marrow mesenchymal stem cell(BMSC)-derived exosomal miR-23b via the tail vein. We found that edema in the rat brain was markedly reduced and rat behaviors were improved after BMSC exosomal miR-23b injection compared with those in the ICH groups. Additionally, exosomal miR-23b was transported to the microglia/macrophages, thereby reducing oxidative stress and pyroptosis after ICH. We also used hemin to mimic ICH conditions in vitro. We found that phosphatase and tensin homolog deleted on chromosome 10(PTEN) was the downstream target gene of miR-23b, and exosomal miR-23b exhibited antioxidant effects by regulating the PTEN/Nrf2 pathway. Moreover, miR-23b reduced PTEN binding to NOD-like receptor family pyrin domain containing 3(NLRP3) and NLRP3 inflammasome activation, thereby decreasing the NLRP3-dependent pyroptosis level. These findings suggest that BMSC-derived exosomal miR-23b exhibits antioxidant effects through inhibiting PTEN and alleviating NLRP3 inflammasome-mediated pyroptosis, thereby promoting neurologic function recovery in rats with ICH.展开更多
Receptor tyrosine kinase-like orphan receptor 2(ROR2)has a vital role in osteogenesis.However,the mechanism underlying the regulation of ROR2 in osteogenic differentiation is still poorly comprehended.A previous study...Receptor tyrosine kinase-like orphan receptor 2(ROR2)has a vital role in osteogenesis.However,the mechanism underlying the regulation of ROR2 in osteogenic differentiation is still poorly comprehended.A previous study by our research group showed that a novel compound heterozygous ROR2 variation accounted for the autosomal recessive Robinow syndrome(ARRS).This study attempted to explore the impact of the ROR2:c.904C>T variant specifically on the osteogenic differentiation of BMSCs.Methods:Coimmunoprecipitation(CoIP)-western blotting was carried out to identify the interaction between ROR2 and Wnt5a.Double-immunofluorescence staining was used for determining the expressions and co-localization of ROR2 and Wnt5a in bone marrow mesenchymal stem cells(BMSCs).Western blot(WB)analysis and quantitative reverse transcription polymerase chain reaction(RT-qPCR)were conducted to identify the expression levels of ROR2 in the BMSCs transfected with LV-shROR2 or LV-ROR2-c.904C>T.The alkaline phosphatase(ALP)activity was detected,and Alizarin Red S staining was done for evaluating the osteogenic differentiation of BMSCs.RT-qPCR was employed to identify the expression of the sphingomyelin synthase 1(SMS1)mRNA in the BMSCs transfected with LV-shROR2 or LV-ROR2-c.904C>T and the mRNA expression levels of Runt-related transcription factor 2(RUNX2),osteocalcin(OCN),and osteopontin(OPN).WB was performed to confirm the protein expressions of extracellular regulated protein kinases1(ERK),P-ERK,Smad family member1/5/8(Smad1/5/8),P-Smad1/5/8,P-P38,P38,RUNX2,OCN,and OPN in the BMSCs transfected with LV-shROR2/LV-ROR2-c.904C>T and sphingomyelin(SM).Results:The ROR2:c.904C>T mutant altered the subcellular localization of the ROR2 protein,which caused an impaired interaction between ROR2 and Wnt5a.The depletion of ROR2 restricted the osteogenic differentiation capability of BMSCs and downregulated the expression of SMS1.SM treatment could reverse the inhibition of osteoblastic differentiation in ROR2-depleted BMSCs.Conclusion:The findings of this work revealed that the ROR2:c.904C>T variant led to the loss of function of ROR2,which impaired the interaction between ROR2 and Wnt5a and also controlled the osteogenic differentiation capability of BMSCs.Furthermore,SM was revealed to be engaged in the osteoblastic differentiation of BMSCs regulated by ROR2,which renders SM a potential target in the therapy for ARRS.展开更多
Objective:To explore the mechanism of circRNA-vgll3 in osteogenic differentiation of human bone marrow mesenchymal stem cells.Methods:BMSCs cells were transfected with circRNA-vgll3,and divided into circRNA-vgll3 high...Objective:To explore the mechanism of circRNA-vgll3 in osteogenic differentiation of human bone marrow mesenchymal stem cells.Methods:BMSCs cells were transfected with circRNA-vgll3,and divided into circRNA-vgll3 high-level group,circRNA-vgll3 low-level group,and negative control group(circRNA-vgll3 not transfected)according to the amount of transfection.The proliferation and apoptosis of BMSCs osteoblasts in each group were analyzed,and the alkaline phosphatase(ALP)activity,type I collagen gray value,bone morphogenetic protein 2(BMP-2),Runx2 protein,and mRNA expression levels were detected.Results:The circRNA-vgll3 low-level group had a significant inhibitory effect on the proliferation of BMSCs osteoblasts,and the apoptosis rate of the circRNA-vgll3 low-level group was significantly higher than that of the circRNA-vgll3 high-level group(P<0.05);ALP activity,type I collagen gray value,BMP-2,Runx2 protein,and mRNA expression levels in the high-level circRNA-vgll3 group were significantly higher than those in the low-level circRNA-vgll3 group,and the difference was statistically significant(P<0.05).Conclusion:Overexpression of circRNA-vgll3 can promote the osteogenic differentiation ability of BMSCs,while low expression of circRNA-vgll3 can inhibit the osteogenic differentiation ability of BMSCs.The main mechanism of action is that circRNA-vgll3 can affect osteogenic differentiation by regulating the Runx2 protein.展开更多
Although many therapeutic interventions have shown promise in treating spinal cord injury, focusing on a single aspect of repair cannot achieve successful and functional regeneration in patients following spinal cord ...Although many therapeutic interventions have shown promise in treating spinal cord injury, focusing on a single aspect of repair cannot achieve successful and functional regeneration in patients following spinal cord injury. In this study, we applied a combinatorial approach for treating spinal cord injury involving neuroprotection and rehabilitation, exploiting cell transplantation and functional sensorimotor training to promote nerve regeneration and functional recovery. Here, we used a mouse model of thoracic contusive spinal cord injury to investigate whether the combination of bone marrow mesenchymal stem cell transplantation and exercise training has a synergistic effect on functional restoration. Locomotor function was evaluated by the Basso Mouse Scale, horizontal ladder test, and footprint analysis. Magnetic resonance imaging, histological examination, transmission electron microscopy observation, immunofluorescence staining, and western blotting were performed 8 weeks after spinal cord injury to further explore the potential mechanism behind the synergistic repair effect. In vivo, the combination of bone marrow mesenchymal stem cell transplantation and exercise showed a better therapeutic effect on motor function than the single treatments. Further investigations revealed that the combination of bone marrow mesenchymal stem cell transplantation and exercise markedly reduced fibrotic scar tissue, protected neurons, and promoted axon and myelin protection. Additionally, the synergistic effects of bone marrow mesenchymal stem cell transplantation and exercise on spinal cord injury recovery occurred via the PI3 K/AKT/mTOR pathway. In vitro, experimental evidence from the PC12 cell line and primary cortical neuron culture also demonstrated that blocking of the PI3 K/AKT/mTOR pathway would aggravate neuronal damage. Thus, bone marrow mesenchymal stem cell transplantation combined with exercise training can effectively restore motor function after spinal cord injury by activating the PI3 K/AKT/mTOR pathway.展开更多
BACKGROUND The low survival rate of mesenchymal stem cells(MSCs)caused by anoikis,a form of apoptosis,limits the therapeutic efficacy of MSCs.As a proapoptotic molecule,mammalian Ste20-like kinase 1(Mst1)can increase ...BACKGROUND The low survival rate of mesenchymal stem cells(MSCs)caused by anoikis,a form of apoptosis,limits the therapeutic efficacy of MSCs.As a proapoptotic molecule,mammalian Ste20-like kinase 1(Mst1)can increase the production of reactive oxygen species(ROS),thereby promoting anoikis.Recently,we found that Mst1 inhibition could protect mouse bone marrow MSCs(mBMSCs)from H 2 O 2-induced cell apoptosis by inducing autophagy and reducing ROS production.However,the influence of Mst1 inhibition on anoikis in mBMSCs remains unclear.AIM To investigate the mechanisms by which Mst1 inhibition acts on anoikis in isolated mBMSCs.METHODS Poly-2-hydroxyethyl methacrylate-induced anoikis was used following the silencing of Mst1 expression by short hairpin RNA(shRNA)adenovirus transfection.Integrin(ITGs)were tested by flow cytometry.Autophagy and ITGα5β1 were inhibited using 3-methyladenine and small interfering RNA,respe-ctively.The alterations in anoikis were measured by Terminal-deoxynucleoitidyl Transferase Mediated Nick End Labeling and anoikis assays.The levels of the anoikis-related proteins ITGα5,ITGβ1,and phospho-focal adhesion kinase and the activation of caspase 3 and the autophagy-related proteins microtubules associated protein 1 light chain 3 II/I,Beclin1 and p62 were detected by Western blotting.RESULTS In isolated mBMSCs,Mst1 expression was upregulated,and Mst1 inhibition significantly reduced cell apoptosis,induced autophagy and decreased ROS levels.Mechanistically,we found that Mst1 inhibition could upregulate ITGα5 and ITGβ1 expression but not ITGα4,ITGαv,or ITGβ3 expression.Moreover,autophagy induced by upregulated ITGα5β1 expression following Mst1 inhibition played an essential role in the protective efficacy of Mst1 inhibition in averting anoikis.CONCLUSION Mst1 inhibition ameliorated autophagy formation,increased ITGα5β1 expression,and decreased the excessive production of ROS,thereby reducing cell apoptosis in isolated mBMSCs.Based on these results,Mst1 inhibition may provide a promising strategy to overcome anoikis of implanted MSCs.展开更多
Spinal cord injury(SCI)is a devastating condition with complex pathological mechanisms that lead to sensory,motor,and autonomic dysfunction below the site of injury.To date,no effective therapy is available for the tr...Spinal cord injury(SCI)is a devastating condition with complex pathological mechanisms that lead to sensory,motor,and autonomic dysfunction below the site of injury.To date,no effective therapy is available for the treatment of SCI.Recently,bone marrow-derived mesenchymal stem cells(BMMSCs)have been considered to be the most promising source for cellular therapies following SCI.The objective of the present review is to summarize the most recent insights into the cellular and molecular mechanism using BMMSC therapy to treat SCI.In this work,we review the specific mechanism of BMMSCs in SCI repair mainly from the following aspects:Neuroprotection,axon sprouting and/or regeneration,myelin regeneration,inhibitory microenvironments,glial scar formation,immunomodulation,and angiogenesis.Additionally,we summarize the latest evidence on the application of BMMSCs in clinical trials and further discuss the challenges and future directions for stem cell therapy in SCI models.展开更多
AIM To investigate the effects of heme oxygenase-1(HO-1)-modified bone marrow mesenchymal stem cells(BMMSCs)on the microcirculation and energy metabolism of hepatic sinusoids following reduced-size liver transplantati...AIM To investigate the effects of heme oxygenase-1(HO-1)-modified bone marrow mesenchymal stem cells(BMMSCs)on the microcirculation and energy metabolism of hepatic sinusoids following reduced-size liver transplantation(RLT)in a rat model.METHODS BMMSCs were isolated and cultured in vitro using an adherent method,and then transduced with HO-1-bearing recombinant adenovirus to construct HO-1/BMMSCs.A rat acute rejection model following 50%RLT was established using a two-cuff technique.Recipients were divided into three groups based on the treatment received:normal saline(NS),BMMSCs and HO-1/BMMSCs.Liver function was examined at six time points.The levels of endothelin-1(ET-1),endothelial nitric-oxide synthase(e NOS),inducible nitric-oxide synthase(i NOS),nitric oxide(NO),and hyaluronic acid(HA)were detected using an enzyme-linked immunosorbent assay.The portal vein pressure(PVP)was detected by Power Lab ML880.The expressions of ET-1,i NOS,e NOS,and von Willebrand factor(v WF)protein in the transplanted liver were detected using immunohistochemistry and Western blotting.ATPase in the transplanted liver was detected by chemical colorimetry,and the ultrastructural changes were observed under a transmission electron microscope.RESULTS HO-1/BMMSCs could alleviate the pathological changes and rejection activity index of the transplanted liver,and improve the liver function of rats following 50%RLT,with statistically significant differences compared with those of the NS group and BMMSCs group(P<0.05).In term of the microcirculation of hepatic sinusoids:The PVP on POD7 decreased significantly in the HO-1/BMMSCs and BMMSCs groups compared with that of the NS group(P<0.01);HO-1/BMMSCs could inhibit the expressions of ET-1 and i NOS,increase the expressions of e NOS and inhibit amounts of NO production,and maintain the equilibrium of ET-1/NO(P<0.05);and HO-1/BMMSCs increased the expression of v WF in hepatic sinusoidal endothelial cells(SECs),and promoted the degradation of HA,compared with those of the NS group and BMMSCs group(P<0.05).In term of the energy metabolism of the transplanted liver,HO-1/BMMSCs repaired the damaged mitochondria,and improved the activity of mitochondrial aspartate aminotransferase(ASTm)and ATPase,compared with the other two groups(P<0.05).CONCLUSION HO-1/BMMSCs can improve the microcirculation of hepatic sinusoids significantly,and recover the energy metabolism of damaged hepatocytes in rats following RLT,thus protecting the transplanted liver.展开更多
Exosomes derived from bone marrow mesenchymal stem cells can inhibit neuroinflammation through regulating microglial phenotypes and promoting nerve injury repair.However,the underlying molecular mechanism remains uncl...Exosomes derived from bone marrow mesenchymal stem cells can inhibit neuroinflammation through regulating microglial phenotypes and promoting nerve injury repair.However,the underlying molecular mechanism remains unclear.In this study,we investigated the mechanism by which exosomes derived from bone marrow mesenchymal stem cells inhibit neuroinflammation.Our in vitro co-culture experiments showed that bone marrow mesenchymal stem cells and their exosomes promoted the polarization of activated BV2 microglia to their anti-inflammatory phenotype,inhibited the expression of proinflammatory cytokines,and increased the expression of anti-inflammatory cytokines.Our in vivo experiments showed that tail vein injection of exosomes reduced cell apoptosis in cortical tissue of mouse models of traumatic brain injury,inhibited neuroinflammation,and promoted the transformation of microglia to the anti-inflammatory phenotype.We screened some microRNAs related to neuroinflammation using microRNA sequencing and found that microRNA-181b seemed to be actively involved in the process.Finally,we regulated the expression of miR181b in the brain tissue of mouse models of traumatic brain injury using lentiviral transfection.We found that miR181b overexpression effectively reduced apoptosis and neuroinflamatory response after traumatic brain injury and promoted the transformation of microglia to the anti-inflammatory phenotype.The interleukin 10/STAT3 pathway was activated during this process.These findings suggest that the inhibitory effects of exosomes derived from bone marrow mesenchymal stem cells on neuroinflamation after traumatic brain injury may be realized by the action of miR181b on the interleukin 10/STAT3 pathway.展开更多
BACKGROUND: Because bone marrow mesenchymal stem cells (BMSCs) do not secrete sufficient brain-derived neurotrophic factor (BDNF), the use of exogenous BDNF could improve microenvironments in injured regions for BMSCs...BACKGROUND: Because bone marrow mesenchymal stem cells (BMSCs) do not secrete sufficient brain-derived neurotrophic factor (BDNF), the use of exogenous BDNF could improve microenvironments in injured regions for BMSCs differentiation. OBJECTIVE: To analyze recovery of the injured spinal cord following BMSCs venous transplantation in combination with consecutive injections of BDNF. DESIGN, TIME AND SETTING: A randomized, controlled animal experiment was performed at the Central Laboratory of First Hospital and Anatomical Laboratory, Fujian Medical University from October 2004 to May 2006. MATERIALS: Human BDNF was purchased from Sigma, USA. METHODS: A total of 44 New Zealand rabbits were randomly assigned to model (n = 8), BDNF (n = 12), BMSC (n = 12), and BMSC+BDNF (n = 12) groups. Spinal cord (L2) injury was established with the dropping method. The model group rabbits were injected with 1 mL normal saline via the ear margin vein; the BDNF group was subdurally injected with 100 μg/d human BDNF for 1 week; the BMSC group was injected with 1 mL BMSCs suspension (2 × 106/mL) via the ear margin vein; and the BMSC+BDNF group rabbits were subdurally injected with 100 μg/d BDNF for 1 week, in addition to BMSCs suspension via the ear margin vein. MAIN OUTCOME MEASURES: BMSCs surface markers were detected by flow cytometry. BMSCs differentiation in the injured spinal cord was detected by immunofluorescence histochemistry. Functional and structural recovery, as well as morphological changes, in the injured spinal cord were respectively detected by Tarlov score, horseradish peroxidase retrograde tracing, and hematoxylin & eosin staining methods at 1, 3, and 5 weeks following transplantation. RESULTS: Transplanted BMSCs differentiated into neuronal-like cells in the injured spinal cord at 3 and 5 weeks following transplantation. Neurological function and pathological damage improved following BMSC + BDNF treatment compared with BDNF or BMSC alone (P < 0.01 or P < 0.05). CONCLUSION: BMSCs venous transplantation in combination with BDNF subdural injection benefits neuronal-like cell differentiation and significantly improves structural and function of injured spinal cord compared with BMSCs or BDNF alone.展开更多
Extracellular matrix( ECM) plays a prominent role in establishing and maintaining an appropriate microenvironment for tissue regeneration. The aims of this study were to construct a tissue engineered scaffold by recon...Extracellular matrix( ECM) plays a prominent role in establishing and maintaining an appropriate microenvironment for tissue regeneration. The aims of this study were to construct a tissue engineered scaffold by reconstituting osteoblast cell-derived ECM( O-ECM) on the electrospun nanofibrous scaffold,and further to evaluate its subsequent application for promoting the proliferation of bone marrow mesenchymal stem cells( BMSCs). To engineer a biomimetic scaffold, calvarial osteoblasts and electrospun poly-llactic acid( PLLA) nanofibers were prepared and subjected to decellularize for O-ECM deposition. To evaluate and characterize the O-ECM/PLLA scaffold, the morphology was examined and several specific mark proteins of osteoblasts matrix were evaluated.Furthermore,the cell counting kit-8( CCK-8) assay was used to detect the proliferation of the BMSCs cultivated on the O-ECM/PLLA scaffold. The results indicated O-ECM/PLLA scaffold was loaded with Collagen I, Fibronectin, and Laminin, as the composition of the marrow ECM. After decellularization,O-ECM deposition was observed in O-ECM/PLLA scaffold. Moreover,the O-ECM/PLLA scaffold could significantly enhance the proliferation of BMSCs,suggesting better cytocompatibility compared to the other groups tested. Taken together,a biomimetic scaffold based on the joint use of O-ECM and PLLA biomaterials,which represents a promising approach to bone tissue engineering, facilitates the expansion of BMSCs in vitro.展开更多
BACKGROUND Collagen is one of the most commonly used natural biomaterials for tendon tissue engineering.One of the possible practical ways to further enhance tendon repair is to combine a porous collagen sponge scaffo...BACKGROUND Collagen is one of the most commonly used natural biomaterials for tendon tissue engineering.One of the possible practical ways to further enhance tendon repair is to combine a porous collagen sponge scaffold with a suitable growth factor or cytokine that has an inherent ability to promote the recruitment,proliferation,and tenogenic differentiation of cells.However,there is an incomplete understanding of which growth factors are sufficient and optimal for the tenogenic differentiation of rat bone marrow mesenchymal stem cells(BMSCs)in a collagen sponge-based 3D culture system.AIM To identify one or more ideal growth factors that benefit the proliferation and tenogenic differentiation of rat BMSCs in a porous collagen sponge scaffold.METHODS We constructed a 3D culture system based on a type I collagen sponge scaffold.The surface topography of the collagen sponge scaffold was observed by scanning electron microscopy.Primary BMSCs were isolated from Sprague-Dawley rats.Cell survival on the surfaces of the scaffolds with different growth factors was assessed by live/dead assay and CCK-8 assay.The mRNA and protein expression levels were confirmed by quantitative real-time polymerase chain reaction and Western blot,respectively.The deposited collagen was assessed by Sirius Red staining.RESULTS Transforming growth factorβ1(TGF-β1)showed great promise in the tenogenic differentiation of BMSCs compared to growth differentiation factor 7(GDF-7)and insulin-like growth factor 1(IGF-1)in both the 2D and 3D cultures,and the 3D culture enhanced the differentiation of BMSCs into tenocytes well beyond the level of induction in the 2D culture after TGF-β1 treatment.In the 2D culture,the proliferation of the BMSCs showed no significant changes compared to the control group after TGF-β1,IGF-1,or GDF-7 treatment.However,TGF-β1 and GDF-7 could increase the cell proliferation in the 3D culture.Strangely,we also found more dead cells in the BMSC-collagen sponge constructs that were treated with TGF-β1.Moreover,TGF-β1 promoted more collagen deposition in both the 2D and 3D cultures.CONCLUSION Collagen sponge-based 3D culture with TGF-β1 enhances the responsiveness of the proliferation and tenogenic differentiation of rat BMSCs.展开更多
Background:Spinal cord injury(SCI)is a serious traumatic disease of the central nervous system,and there is currently no effective treatment for SCI because of its complicated pathophysiology.Bone marrow mesenchymal s...Background:Spinal cord injury(SCI)is a serious traumatic disease of the central nervous system,and there is currently no effective treatment for SCI because of its complicated pathophysiology.Bone marrow mesenchymal stem cells(BMSCs)have multidirectional differentiation abilities.Our study aims to explore the effects of bone morphogenetic protein 7(BMP-7)-modified BMSCs transplantation on the repair of SCI in rats.Methods:In this study,a rat spinal cord injury model was established with the modified Allen method.Then,BMSCs transfected with the BMP7 gene were transplanted to treat the spinal cord injury in rats.Forty Sprague-Dawley rats were randomly divided into the sham operation group(sham group),spinal cord injury group(model group),BMSC treatment group(BMSC group)and LV-BMP7-BMSC treatment group(LV-BMP7-BMSC group).The Basso,Beattie,and Bresnahan(BBB)score was used to evaluate the recovery of hindlimb function in the rats.The levels of neurofilament protein NF-200(NF-200)and glial fibrillary acidic protein(GFAP)were detected by immunofluorescence,RT-PCR and Western blotting.Results:At 14 d,21 d,and 28 d after treatment,the BBB score of the rats in the LV-BMP7-BMSC group was higher than that of the rats in the model group and BMSC group.The results showed that NF-200 was expressed at the local spinal cord injury site.Compared with that of the sham group,the NF-200 expression level of the BMSC group and LV-BMP7-BMSC group was increased(P<0.05).The results showed that the mRNA expression levels of NF-200 in the spinal cord tissue of the BMSC group and LV-BMP7-BMSC group were increased compared with those of the sham group(P<0.05).The western blotting results further confirmed the PCR results.Conclusion:BMP-7 gene-modified BMSC transplantation can promote the repair of spinal cord functions after SCI in rats.展开更多
Objective:To investigate the effect ofα1-antitrypsin combined with bone marrow mesenchymal stem cells on retinopathy in diabetic rats and its mechanism.Methods:A model of diabetic retinopathy was established by intra...Objective:To investigate the effect ofα1-antitrypsin combined with bone marrow mesenchymal stem cells on retinopathy in diabetic rats and its mechanism.Methods:A model of diabetic retinopathy was established by intraperitoneal injection of streptozotocin.The 30 Wistar rats successfully modeled were randomly divided into a model group,a bone marrow mesenchymal stem cell group and a combined group(α1-antitrypsin combined with bone marrow Mesenchymal stem cells),the blood glucose and serum insulin levels of diabetic rats were measured 4 weeks after treatment.Enzyme-linked immunosorbent assay(ELISA)for measuring serum inflammatory factors IL-1β,IL-6 and TNF-α in rats.Observing the pathological morphology of rat retina under hematoxylin-eosin staining(HE).TUNEL staining to observe the apoptosis of rat retinal nerve cells.Immunohistochemical method to detect the expression level of CD45 in retinal tissue.Real-time fluorescence quantitative PCR was used to detect the expression of retinal vascular endothelial growth factor(VEGF),hypoxiainducible factor-1α(HIF-1α),and angiotensinⅡ(ANGⅡ)mRNA.Western blot was used to detect the expression of p38 MAPK/NF-κB signaling pathway-related proteins in the retinal tissue of each group of rats.Results:Compared with the control group,the rats in the model group had increased blood glucose,decreased insulin levels,increased serum IL-1β,IL-6,and TNF-α levels,and had obvious lesions in the retina.CD45 showed high expression in retinal tissue,VEGF,HIF-1α,ANGⅡ mRNA expression increased,p-p38,p-p65,p-IκBα protein expression increased(P<0.05).Compared with the model group,the bone marrow mesenchymal stem cell group and the combined group have decreased blood glucose,increased insulin levels,and decreased serum IL-1β,IL-6 and TNF-α levels.Retinopathy is improved,apoptosis of retinal nerve cells is reduced,CD45 expression in retinal tissue is reduced,VEGF,HIF-1α,ANGⅡ mRNA expression is decreased,and p-p38,p-p65,p-IκBα protein expression is decreased.Compared with the bone marrow mesenchymal stem cell group,the effect of the combined group was more obvious(P<0.05).Conclusion:α1-antitrypsin combined with bone marrow mesenchymal stem cell transplantation can improve the degree of retinopathy in diabetic rats.The mechanism may be related to the inhibition of p38 MAPK/NF-κB signaling pathway.展开更多
Objective To investigate the effects and mechanism of calcitonin gene-related peptide(CGRP)and substance P (SP) on proliferation of rat bone marrow mesenchymal stem cells.Methods The rBMSCs were isolated using whole b...Objective To investigate the effects and mechanism of calcitonin gene-related peptide(CGRP)and substance P (SP) on proliferation of rat bone marrow mesenchymal stem cells.Methods The rBMSCs were isolated using whole bone marrow展开更多
Objective To study the effect and mechanism of neurological function recovery in rats with spinal cord injury ( SCI) rats after transplantation of neural stem cells which are directly differentiated from bone marrow m...Objective To study the effect and mechanism of neurological function recovery in rats with spinal cord injury ( SCI) rats after transplantation of neural stem cells which are directly differentiated from bone marrow mesenchymal stem cells ( BMSC ) ,and to investigate the suitable engraftment time. Methods BMSC at 3rd passage were differentiated into neural stem cells ( NSC) , and immunofluorescence staining was used to展开更多
BACKGROUND Bone marrow mesenchymal stem cells(BMSCs)are capable of shifting the microglia/macrophages phenotype from M1 to M2,contributing to BMSCsinduced brain repair.However,the regulatory mechanism of BMSCs on micr...BACKGROUND Bone marrow mesenchymal stem cells(BMSCs)are capable of shifting the microglia/macrophages phenotype from M1 to M2,contributing to BMSCsinduced brain repair.However,the regulatory mechanism of BMSCs on microglia/macrophages after ischemic stroke is unclear.Recent evidence suggests that mesencephalic astrocyte-derived neurotrophic factor(MANF)and plateletderived growth factor-AA(PDGF-AA)/MANF signaling regulate M1/M2 macrophage polarization.AIM To investigate whether and how MANF or PDGF-AA/MANF signaling influences BMSCs-mediated M2 polarization.METHODS We identified the secretion of MANF by BMSCs and developed transgenic BMSCs using a targeting small interfering RNA for knockdown of MANF expression.Using a rat middle cerebral artery occlusion(MCAO)model transplanted by BMSCs and BMSCs-microglia Transwell coculture system,the effect of BMSCsinduced downregulation of MANF expression on the phenotype of microglia/macrophages was tested by Western blot,quantitative reverse transcription-polymerase chain reaction,and immunofluorescence.Additionally,microglia were transfected with mimics of miR-30a*,which inuenced expression of X-box binding protein(XBP)1,a key transcription factor that synergized with activating transcription factor 6(ATF6)to govern MANF expression.We examined the levels of miR-30a*,ATF6,XBP1,and MANF after PDGF-AA treatment in the activated microglia.RESULTS Inhibition of MANF attenuated BMSCs-induced functional recovery and decreased M2 marker production,but increased M1 marker expression in vivo or in vitro.Furthermore,PDGF-AA treatment decreased miR-30a*expression,had no influence on the levels of ATF6,but enhanced expression of both XBP1 and MANF.CONCLUSION BMSCs-mediated MANF paracrine signaling,in particular the PDGF-AA/miR-30a*/XBP1/MANF pathway,synergistically mediates BMSCs-induced M2 polarization.展开更多
Background:Perturbations in bone marrow mesenchymal stem cell(BMSC)differentiation play an important role in steroid-induced osteonecrosis of the femoral head(SONFH).At present,studies on SONFH concentrate upon the ba...Background:Perturbations in bone marrow mesenchymal stem cell(BMSC)differentiation play an important role in steroid-induced osteonecrosis of the femoral head(SONFH).At present,studies on SONFH concentrate upon the balance within BMSC osteogenic and adipogenic differentiation.However,BMSC apoptosis as well as proliferation are important prerequisites in their differentiation.The hedgehog(HH)signaling pathway regulates bone cell apoptosis.Baicalin(BA),a well-known compound in traditional Chinese medicine,can affect the proliferation and apoptosis of numerous cell types via HH signaling.However,the potential role and mechanisms of BA on BMSCs are unclear.Thus,we aimed to explore the role of BA in dexamethasone(Dex)-induced BMSC apoptosis in this study.Methods:Primary BMSCs were treated with 10-6 mol/L Dex alone or with 5.0μmol/L,10.0μmol/L,or 50.0μmol/L BA for 24 hours followed by co-treatment with 5.0μmol/L,10.0μmol/L,or 50.0μmol/L BA and 10-6 mol/L Dex.Cell viability was assayed through the Cell Counting Kit-8(CCK-8).Cell apoptosis was evaluated using Annexin V-fluorescein isothiocyanate/propidium iodide(PI)staining followed by flow cytometry.The imaging and counting,respectively,of Hochest 33342/PI-stained cells were used to assess the morphological characteristics and proportion of apoptotic cells.To quantify the apoptosis-related proteins(e.g.,apoptosis regulator BAX[Bax],B-cell lymphoma 2[Bcl-2],caspase-3,and cleaved caspase-3)and HH signaling pathway proteins,western blotting was used.A HH-signaling pathway inhibitor was used to demonstrate that BA exerts its anti-apoptotic effects via the HH signaling pathway.Results:The results of CCK-8,Hoechst 33342/PI-staining,and flow cytometry showed that BA did not significantly promote cell proliferation(CCK-8:0μmol/L,100%;2.5μmol/L,98.58%;5.0μmol/L,95.18%;10.0μmol/L,98.11%;50.0μmol/L,99.38%,F=2.33,P>0.05),but it did attenuate the effect of Dex on apoptosis(Hoechst 33342/PI-staining:Dex+50.0μmol/L BA,12.27%vs.Dex,39.27%,t=20.62;flow cytometry:Dex+50.0μmol/L BA,12.68%vs.Dex,37.43%,t=11.56;Both P<0.05).The results of western blotting analysis showed that BA reversed Dex-induced apoptosis by activating the HH signaling pathway,which down-regulated the expression of Bax,cleaved-caspase 3,and suppressor of fused(SUFU)while up-regulating Bcl-2,sonic hedgehog(SHH),and zinc finger protein GLI-1(GLI-1)expression(Bax/Bcl-2:Dex+50.0μmol/L BA,1.09 vs.Dex,2.76,t=35.12;cleaved caspase-3/caspase-3:Dex+50.0μmol/L BA,0.38 vs.Dex,0.73,t=10.62;SHH:Dex+50.0μmol/L BA,0.50 vs.Dex,0.12,t=34.01;SUFU:Dex+50.0μmol/L BA,0.75 vs.Dex,1.19,t=10.78;GLI-1:Dex+50.0μmol/L BA,0.40 vs.Dex,0.11,t=30.68.All P<0.05).Conclusions:BA antagonizes Dex-induced apoptosis of human BMSCs by activating the HH signaling pathway.It is a potential candidate for preventing SONFH.展开更多
Mesenchymalstemcells(MSCs)areidealcandidatesfortreatingmanycardiovasculardiseases.MSCscanmodify the internal cardiac microenvironment to facilitate their immunomodulatory and differentiation abilities,which are essent...Mesenchymalstemcells(MSCs)areidealcandidatesfortreatingmanycardiovasculardiseases.MSCscanmodify the internal cardiac microenvironment to facilitate their immunomodulatory and differentiation abilities,which are essential to restore heart function.MSCs can be easily isolated from different sources,including bone marrow,adipose tissues,umbilical cord,and dental pulp.MSCs from various sources differ in their regenerative and therapeutic abilities for cardiovascular disorders.In this review,we will summarize the therapeutic potential of each MSC source for heart diseases and highlight the possible molecular mechanisms of each source to restore cardiac function.展开更多
基金supported by the Fujian Minimally Invasive Medical Center Foundation,No.2128100514(to CC,CW,HX)the Natural Science Foundation of Fujian Province,No.2023J01640(to CC,CW,ZL,HX)。
文摘Spinal cord injury is a disabling condition with limited treatment options.Multiple studies have provided evidence suggesting that small extracellular vesicles(SEVs)secreted by bone marrow mesenchymal stem cells(MSCs)help mediate the beneficial effects conferred by MSC transplantation following spinal cord injury.Strikingly,hypoxia-preconditioned bone marrow mesenchymal stem cell-derived SEVs(HSEVs)exhibit increased therapeutic potency.We thus explored the role of HSEVs in macrophage immune regulation after spinal cord injury in rats and their significance in spinal cord repair.SEVs or HSEVs were isolated from bone marrow MSC supernatants by density gradient ultracentrifugation.HSEV administration to rats via tail vein injection after spinal cord injury reduced the lesion area and attenuated spinal cord inflammation.HSEVs regulate macrophage polarization towards the M2 phenotype in vivo and in vitro.Micro RNA sequencing and bioinformatics analyses of SEVs and HSEVs revealed that mi R-146a-5p is a potent mediator of macrophage polarization that targets interleukin-1 receptor-associated kinase 1.Reducing mi R-146a-5p expression in HSEVs partially attenuated macrophage polarization.Our data suggest that HSEVs attenuate spinal cord inflammation and injury in rats by transporting mi R-146a-5p,which alters macrophage polarization.This study provides new insights into the application of HSEVs as a therapeutic tool for spinal cord injury.
基金supported by the National Natural Science Foundation of China,No.81971231(to JL)the Natural Science Foundation of Liaoning Province,No.2022-MS-391(to PW)the Scientific Research Project from the Education Department of Liaoning Province,Nos.JYTQN2020011(to PW),LJKQZ2021147(to JL)。
文摘Exosomes derived from human bone marrow mesenchymal stem cells(MSC-Exo)are characterized by easy expansion and storage,low risk of tumor formation,low immunogenicity,and anti-inflammatory effects.The therapeutic effects of MSC-Exo on ischemic stroke have been widely explored.However,the underlying mechanism remains unclear.In this study,we established a mouse model of ischemic brain injury induced by occlusion of the middle cerebral artery using the thread bolt method and injected MSC-Exo into the tail vein.We found that administration of MSC-Exo reduced the volume of cerebral infarction in the ischemic brain injury mouse model,increased the levels of interleukin-33(IL-33)and suppression of tumorigenicity 2 receptor(ST2)in the penumbra of cerebral infarction,and improved neurological function.In vitro results showed that astrocyte-conditioned medium of cells deprived of both oxygen and glucose,to simulate ischemia conditions,combined with MSC-Exo increased the survival rate of primary cortical neurons.However,after transfection by IL-33 siRNA or ST2 siRNA,the survival rate of primary cortical neurons was markedly decreased.These results indicated that MSC-Exo inhibited neuronal death induced by oxygen and glucose deprivation through the IL-33/ST2 signaling pathway in astrocytes.These findings suggest that MSC-Exo may reduce ischemia-induced brain injury through regulating the IL-33/ST2 signaling pathway.Therefore,MSC-Exo may be a potential therapeutic method for ischemic stroke.
基金supported by the National Natural Science Foundation of China,No.81571120(to ZYH).
文摘Our previous studies showed that miR-23b was downregulated in patients with intracerebral hemorrhage(ICH). This indicates that miR-23b may be closely related to the patho-physiological mechanism of ICH, but this hypothesis lacks direct evidence. In this study, we established rat models of ICH by injecting collagenase Ⅶ into the right basal ganglia and treating them with an injection of bone marrow mesenchymal stem cell(BMSC)-derived exosomal miR-23b via the tail vein. We found that edema in the rat brain was markedly reduced and rat behaviors were improved after BMSC exosomal miR-23b injection compared with those in the ICH groups. Additionally, exosomal miR-23b was transported to the microglia/macrophages, thereby reducing oxidative stress and pyroptosis after ICH. We also used hemin to mimic ICH conditions in vitro. We found that phosphatase and tensin homolog deleted on chromosome 10(PTEN) was the downstream target gene of miR-23b, and exosomal miR-23b exhibited antioxidant effects by regulating the PTEN/Nrf2 pathway. Moreover, miR-23b reduced PTEN binding to NOD-like receptor family pyrin domain containing 3(NLRP3) and NLRP3 inflammasome activation, thereby decreasing the NLRP3-dependent pyroptosis level. These findings suggest that BMSC-derived exosomal miR-23b exhibits antioxidant effects through inhibiting PTEN and alleviating NLRP3 inflammasome-mediated pyroptosis, thereby promoting neurologic function recovery in rats with ICH.
基金funded by the Project Funded by China Postdoctoral Science Foundation(No.2022T150445)the Beijing Hospitals Authority Youth Programme(No.QML20211401)+1 种基金the Young Talent Foundation of PLA General Hospital(2019-YQPY-002)Beijing Nova Program(Z201100006820057).
文摘Receptor tyrosine kinase-like orphan receptor 2(ROR2)has a vital role in osteogenesis.However,the mechanism underlying the regulation of ROR2 in osteogenic differentiation is still poorly comprehended.A previous study by our research group showed that a novel compound heterozygous ROR2 variation accounted for the autosomal recessive Robinow syndrome(ARRS).This study attempted to explore the impact of the ROR2:c.904C>T variant specifically on the osteogenic differentiation of BMSCs.Methods:Coimmunoprecipitation(CoIP)-western blotting was carried out to identify the interaction between ROR2 and Wnt5a.Double-immunofluorescence staining was used for determining the expressions and co-localization of ROR2 and Wnt5a in bone marrow mesenchymal stem cells(BMSCs).Western blot(WB)analysis and quantitative reverse transcription polymerase chain reaction(RT-qPCR)were conducted to identify the expression levels of ROR2 in the BMSCs transfected with LV-shROR2 or LV-ROR2-c.904C>T.The alkaline phosphatase(ALP)activity was detected,and Alizarin Red S staining was done for evaluating the osteogenic differentiation of BMSCs.RT-qPCR was employed to identify the expression of the sphingomyelin synthase 1(SMS1)mRNA in the BMSCs transfected with LV-shROR2 or LV-ROR2-c.904C>T and the mRNA expression levels of Runt-related transcription factor 2(RUNX2),osteocalcin(OCN),and osteopontin(OPN).WB was performed to confirm the protein expressions of extracellular regulated protein kinases1(ERK),P-ERK,Smad family member1/5/8(Smad1/5/8),P-Smad1/5/8,P-P38,P38,RUNX2,OCN,and OPN in the BMSCs transfected with LV-shROR2/LV-ROR2-c.904C>T and sphingomyelin(SM).Results:The ROR2:c.904C>T mutant altered the subcellular localization of the ROR2 protein,which caused an impaired interaction between ROR2 and Wnt5a.The depletion of ROR2 restricted the osteogenic differentiation capability of BMSCs and downregulated the expression of SMS1.SM treatment could reverse the inhibition of osteoblastic differentiation in ROR2-depleted BMSCs.Conclusion:The findings of this work revealed that the ROR2:c.904C>T variant led to the loss of function of ROR2,which impaired the interaction between ROR2 and Wnt5a and also controlled the osteogenic differentiation capability of BMSCs.Furthermore,SM was revealed to be engaged in the osteoblastic differentiation of BMSCs regulated by ROR2,which renders SM a potential target in the therapy for ARRS.
文摘Objective:To explore the mechanism of circRNA-vgll3 in osteogenic differentiation of human bone marrow mesenchymal stem cells.Methods:BMSCs cells were transfected with circRNA-vgll3,and divided into circRNA-vgll3 high-level group,circRNA-vgll3 low-level group,and negative control group(circRNA-vgll3 not transfected)according to the amount of transfection.The proliferation and apoptosis of BMSCs osteoblasts in each group were analyzed,and the alkaline phosphatase(ALP)activity,type I collagen gray value,bone morphogenetic protein 2(BMP-2),Runx2 protein,and mRNA expression levels were detected.Results:The circRNA-vgll3 low-level group had a significant inhibitory effect on the proliferation of BMSCs osteoblasts,and the apoptosis rate of the circRNA-vgll3 low-level group was significantly higher than that of the circRNA-vgll3 high-level group(P<0.05);ALP activity,type I collagen gray value,BMP-2,Runx2 protein,and mRNA expression levels in the high-level circRNA-vgll3 group were significantly higher than those in the low-level circRNA-vgll3 group,and the difference was statistically significant(P<0.05).Conclusion:Overexpression of circRNA-vgll3 can promote the osteogenic differentiation ability of BMSCs,while low expression of circRNA-vgll3 can inhibit the osteogenic differentiation ability of BMSCs.The main mechanism of action is that circRNA-vgll3 can affect osteogenic differentiation by regulating the Runx2 protein.
基金supported by the National Key R&D Program of China,No.2020YFC2008502 (to QW)the National Natural Science Foundation of China,No. 82172534 (to QW)。
文摘Although many therapeutic interventions have shown promise in treating spinal cord injury, focusing on a single aspect of repair cannot achieve successful and functional regeneration in patients following spinal cord injury. In this study, we applied a combinatorial approach for treating spinal cord injury involving neuroprotection and rehabilitation, exploiting cell transplantation and functional sensorimotor training to promote nerve regeneration and functional recovery. Here, we used a mouse model of thoracic contusive spinal cord injury to investigate whether the combination of bone marrow mesenchymal stem cell transplantation and exercise training has a synergistic effect on functional restoration. Locomotor function was evaluated by the Basso Mouse Scale, horizontal ladder test, and footprint analysis. Magnetic resonance imaging, histological examination, transmission electron microscopy observation, immunofluorescence staining, and western blotting were performed 8 weeks after spinal cord injury to further explore the potential mechanism behind the synergistic repair effect. In vivo, the combination of bone marrow mesenchymal stem cell transplantation and exercise showed a better therapeutic effect on motor function than the single treatments. Further investigations revealed that the combination of bone marrow mesenchymal stem cell transplantation and exercise markedly reduced fibrotic scar tissue, protected neurons, and promoted axon and myelin protection. Additionally, the synergistic effects of bone marrow mesenchymal stem cell transplantation and exercise on spinal cord injury recovery occurred via the PI3 K/AKT/mTOR pathway. In vitro, experimental evidence from the PC12 cell line and primary cortical neuron culture also demonstrated that blocking of the PI3 K/AKT/mTOR pathway would aggravate neuronal damage. Thus, bone marrow mesenchymal stem cell transplantation combined with exercise training can effectively restore motor function after spinal cord injury by activating the PI3 K/AKT/mTOR pathway.
基金Supported by Natural Science Foundation of Shandong Province,China,No.ZR2020MH014,No.ZR2021QH179 and No.ZR2021MH182.
文摘BACKGROUND The low survival rate of mesenchymal stem cells(MSCs)caused by anoikis,a form of apoptosis,limits the therapeutic efficacy of MSCs.As a proapoptotic molecule,mammalian Ste20-like kinase 1(Mst1)can increase the production of reactive oxygen species(ROS),thereby promoting anoikis.Recently,we found that Mst1 inhibition could protect mouse bone marrow MSCs(mBMSCs)from H 2 O 2-induced cell apoptosis by inducing autophagy and reducing ROS production.However,the influence of Mst1 inhibition on anoikis in mBMSCs remains unclear.AIM To investigate the mechanisms by which Mst1 inhibition acts on anoikis in isolated mBMSCs.METHODS Poly-2-hydroxyethyl methacrylate-induced anoikis was used following the silencing of Mst1 expression by short hairpin RNA(shRNA)adenovirus transfection.Integrin(ITGs)were tested by flow cytometry.Autophagy and ITGα5β1 were inhibited using 3-methyladenine and small interfering RNA,respe-ctively.The alterations in anoikis were measured by Terminal-deoxynucleoitidyl Transferase Mediated Nick End Labeling and anoikis assays.The levels of the anoikis-related proteins ITGα5,ITGβ1,and phospho-focal adhesion kinase and the activation of caspase 3 and the autophagy-related proteins microtubules associated protein 1 light chain 3 II/I,Beclin1 and p62 were detected by Western blotting.RESULTS In isolated mBMSCs,Mst1 expression was upregulated,and Mst1 inhibition significantly reduced cell apoptosis,induced autophagy and decreased ROS levels.Mechanistically,we found that Mst1 inhibition could upregulate ITGα5 and ITGβ1 expression but not ITGα4,ITGαv,or ITGβ3 expression.Moreover,autophagy induced by upregulated ITGα5β1 expression following Mst1 inhibition played an essential role in the protective efficacy of Mst1 inhibition in averting anoikis.CONCLUSION Mst1 inhibition ameliorated autophagy formation,increased ITGα5β1 expression,and decreased the excessive production of ROS,thereby reducing cell apoptosis in isolated mBMSCs.Based on these results,Mst1 inhibition may provide a promising strategy to overcome anoikis of implanted MSCs.
基金Supported by the National Key R&D Program of China,No.2020YFC2008502。
文摘Spinal cord injury(SCI)is a devastating condition with complex pathological mechanisms that lead to sensory,motor,and autonomic dysfunction below the site of injury.To date,no effective therapy is available for the treatment of SCI.Recently,bone marrow-derived mesenchymal stem cells(BMMSCs)have been considered to be the most promising source for cellular therapies following SCI.The objective of the present review is to summarize the most recent insights into the cellular and molecular mechanism using BMMSC therapy to treat SCI.In this work,we review the specific mechanism of BMMSCs in SCI repair mainly from the following aspects:Neuroprotection,axon sprouting and/or regeneration,myelin regeneration,inhibitory microenvironments,glial scar formation,immunomodulation,and angiogenesis.Additionally,we summarize the latest evidence on the application of BMMSCs in clinical trials and further discuss the challenges and future directions for stem cell therapy in SCI models.
基金Supported by The National Natural Science Foundation of China,No.81670574,No.81441022 and No.81270528The Natural Science Foundation of Tianjin,China,No.08JCYBJC08400,No.11JCZDJC27800,and No.12JCZDJC25200the Technology Foundation of the Health Bureau in Tianjin,China,No.2011KY11
文摘AIM To investigate the effects of heme oxygenase-1(HO-1)-modified bone marrow mesenchymal stem cells(BMMSCs)on the microcirculation and energy metabolism of hepatic sinusoids following reduced-size liver transplantation(RLT)in a rat model.METHODS BMMSCs were isolated and cultured in vitro using an adherent method,and then transduced with HO-1-bearing recombinant adenovirus to construct HO-1/BMMSCs.A rat acute rejection model following 50%RLT was established using a two-cuff technique.Recipients were divided into three groups based on the treatment received:normal saline(NS),BMMSCs and HO-1/BMMSCs.Liver function was examined at six time points.The levels of endothelin-1(ET-1),endothelial nitric-oxide synthase(e NOS),inducible nitric-oxide synthase(i NOS),nitric oxide(NO),and hyaluronic acid(HA)were detected using an enzyme-linked immunosorbent assay.The portal vein pressure(PVP)was detected by Power Lab ML880.The expressions of ET-1,i NOS,e NOS,and von Willebrand factor(v WF)protein in the transplanted liver were detected using immunohistochemistry and Western blotting.ATPase in the transplanted liver was detected by chemical colorimetry,and the ultrastructural changes were observed under a transmission electron microscope.RESULTS HO-1/BMMSCs could alleviate the pathological changes and rejection activity index of the transplanted liver,and improve the liver function of rats following 50%RLT,with statistically significant differences compared with those of the NS group and BMMSCs group(P<0.05).In term of the microcirculation of hepatic sinusoids:The PVP on POD7 decreased significantly in the HO-1/BMMSCs and BMMSCs groups compared with that of the NS group(P<0.01);HO-1/BMMSCs could inhibit the expressions of ET-1 and i NOS,increase the expressions of e NOS and inhibit amounts of NO production,and maintain the equilibrium of ET-1/NO(P<0.05);and HO-1/BMMSCs increased the expression of v WF in hepatic sinusoidal endothelial cells(SECs),and promoted the degradation of HA,compared with those of the NS group and BMMSCs group(P<0.05).In term of the energy metabolism of the transplanted liver,HO-1/BMMSCs repaired the damaged mitochondria,and improved the activity of mitochondrial aspartate aminotransferase(ASTm)and ATPase,compared with the other two groups(P<0.05).CONCLUSION HO-1/BMMSCs can improve the microcirculation of hepatic sinusoids significantly,and recover the energy metabolism of damaged hepatocytes in rats following RLT,thus protecting the transplanted liver.
基金supported by the National Natural Science Foundation of China, Nos.81971159(to LW), 81771317(to JFF)
文摘Exosomes derived from bone marrow mesenchymal stem cells can inhibit neuroinflammation through regulating microglial phenotypes and promoting nerve injury repair.However,the underlying molecular mechanism remains unclear.In this study,we investigated the mechanism by which exosomes derived from bone marrow mesenchymal stem cells inhibit neuroinflammation.Our in vitro co-culture experiments showed that bone marrow mesenchymal stem cells and their exosomes promoted the polarization of activated BV2 microglia to their anti-inflammatory phenotype,inhibited the expression of proinflammatory cytokines,and increased the expression of anti-inflammatory cytokines.Our in vivo experiments showed that tail vein injection of exosomes reduced cell apoptosis in cortical tissue of mouse models of traumatic brain injury,inhibited neuroinflammation,and promoted the transformation of microglia to the anti-inflammatory phenotype.We screened some microRNAs related to neuroinflammation using microRNA sequencing and found that microRNA-181b seemed to be actively involved in the process.Finally,we regulated the expression of miR181b in the brain tissue of mouse models of traumatic brain injury using lentiviral transfection.We found that miR181b overexpression effectively reduced apoptosis and neuroinflamatory response after traumatic brain injury and promoted the transformation of microglia to the anti-inflammatory phenotype.The interleukin 10/STAT3 pathway was activated during this process.These findings suggest that the inhibitory effects of exosomes derived from bone marrow mesenchymal stem cells on neuroinflamation after traumatic brain injury may be realized by the action of miR181b on the interleukin 10/STAT3 pathway.
基金the Major Program of Fujian Provincial Science and Technology Department, No. 2002Y014
文摘BACKGROUND: Because bone marrow mesenchymal stem cells (BMSCs) do not secrete sufficient brain-derived neurotrophic factor (BDNF), the use of exogenous BDNF could improve microenvironments in injured regions for BMSCs differentiation. OBJECTIVE: To analyze recovery of the injured spinal cord following BMSCs venous transplantation in combination with consecutive injections of BDNF. DESIGN, TIME AND SETTING: A randomized, controlled animal experiment was performed at the Central Laboratory of First Hospital and Anatomical Laboratory, Fujian Medical University from October 2004 to May 2006. MATERIALS: Human BDNF was purchased from Sigma, USA. METHODS: A total of 44 New Zealand rabbits were randomly assigned to model (n = 8), BDNF (n = 12), BMSC (n = 12), and BMSC+BDNF (n = 12) groups. Spinal cord (L2) injury was established with the dropping method. The model group rabbits were injected with 1 mL normal saline via the ear margin vein; the BDNF group was subdurally injected with 100 μg/d human BDNF for 1 week; the BMSC group was injected with 1 mL BMSCs suspension (2 × 106/mL) via the ear margin vein; and the BMSC+BDNF group rabbits were subdurally injected with 100 μg/d BDNF for 1 week, in addition to BMSCs suspension via the ear margin vein. MAIN OUTCOME MEASURES: BMSCs surface markers were detected by flow cytometry. BMSCs differentiation in the injured spinal cord was detected by immunofluorescence histochemistry. Functional and structural recovery, as well as morphological changes, in the injured spinal cord were respectively detected by Tarlov score, horseradish peroxidase retrograde tracing, and hematoxylin & eosin staining methods at 1, 3, and 5 weeks following transplantation. RESULTS: Transplanted BMSCs differentiated into neuronal-like cells in the injured spinal cord at 3 and 5 weeks following transplantation. Neurological function and pathological damage improved following BMSC + BDNF treatment compared with BDNF or BMSC alone (P < 0.01 or P < 0.05). CONCLUSION: BMSCs venous transplantation in combination with BDNF subdural injection benefits neuronal-like cell differentiation and significantly improves structural and function of injured spinal cord compared with BMSCs or BDNF alone.
基金Shanghai Municipal Natural Science Foundation,China(No.15ZR1400500)the Fundamental Research Funds for the Central Universities,China(Nos.16D110520,EG2017011)
文摘Extracellular matrix( ECM) plays a prominent role in establishing and maintaining an appropriate microenvironment for tissue regeneration. The aims of this study were to construct a tissue engineered scaffold by reconstituting osteoblast cell-derived ECM( O-ECM) on the electrospun nanofibrous scaffold,and further to evaluate its subsequent application for promoting the proliferation of bone marrow mesenchymal stem cells( BMSCs). To engineer a biomimetic scaffold, calvarial osteoblasts and electrospun poly-llactic acid( PLLA) nanofibers were prepared and subjected to decellularize for O-ECM deposition. To evaluate and characterize the O-ECM/PLLA scaffold, the morphology was examined and several specific mark proteins of osteoblasts matrix were evaluated.Furthermore,the cell counting kit-8( CCK-8) assay was used to detect the proliferation of the BMSCs cultivated on the O-ECM/PLLA scaffold. The results indicated O-ECM/PLLA scaffold was loaded with Collagen I, Fibronectin, and Laminin, as the composition of the marrow ECM. After decellularization,O-ECM deposition was observed in O-ECM/PLLA scaffold. Moreover,the O-ECM/PLLA scaffold could significantly enhance the proliferation of BMSCs,suggesting better cytocompatibility compared to the other groups tested. Taken together,a biomimetic scaffold based on the joint use of O-ECM and PLLA biomaterials,which represents a promising approach to bone tissue engineering, facilitates the expansion of BMSCs in vitro.
基金Supported by Natural National Science Foundation of China,No.31700810 and No.11772073Science and Technology Research Program of Chongqing Municipal Education Commission,No.KJQN201800601+1 种基金Natural Science Foundation of Chongqing,China,No.cstc2020jcyj-msxmX0760Visiting Scholar Foundation of Key Laboratory of Biorheological Science and Technology(Chongqing University),Ministry of Education,No.CQKLBST-2018-007.
文摘BACKGROUND Collagen is one of the most commonly used natural biomaterials for tendon tissue engineering.One of the possible practical ways to further enhance tendon repair is to combine a porous collagen sponge scaffold with a suitable growth factor or cytokine that has an inherent ability to promote the recruitment,proliferation,and tenogenic differentiation of cells.However,there is an incomplete understanding of which growth factors are sufficient and optimal for the tenogenic differentiation of rat bone marrow mesenchymal stem cells(BMSCs)in a collagen sponge-based 3D culture system.AIM To identify one or more ideal growth factors that benefit the proliferation and tenogenic differentiation of rat BMSCs in a porous collagen sponge scaffold.METHODS We constructed a 3D culture system based on a type I collagen sponge scaffold.The surface topography of the collagen sponge scaffold was observed by scanning electron microscopy.Primary BMSCs were isolated from Sprague-Dawley rats.Cell survival on the surfaces of the scaffolds with different growth factors was assessed by live/dead assay and CCK-8 assay.The mRNA and protein expression levels were confirmed by quantitative real-time polymerase chain reaction and Western blot,respectively.The deposited collagen was assessed by Sirius Red staining.RESULTS Transforming growth factorβ1(TGF-β1)showed great promise in the tenogenic differentiation of BMSCs compared to growth differentiation factor 7(GDF-7)and insulin-like growth factor 1(IGF-1)in both the 2D and 3D cultures,and the 3D culture enhanced the differentiation of BMSCs into tenocytes well beyond the level of induction in the 2D culture after TGF-β1 treatment.In the 2D culture,the proliferation of the BMSCs showed no significant changes compared to the control group after TGF-β1,IGF-1,or GDF-7 treatment.However,TGF-β1 and GDF-7 could increase the cell proliferation in the 3D culture.Strangely,we also found more dead cells in the BMSC-collagen sponge constructs that were treated with TGF-β1.Moreover,TGF-β1 promoted more collagen deposition in both the 2D and 3D cultures.CONCLUSION Collagen sponge-based 3D culture with TGF-β1 enhances the responsiveness of the proliferation and tenogenic differentiation of rat BMSCs.
基金This study was supported by the China Natural Science Foundation,No.81560216.
文摘Background:Spinal cord injury(SCI)is a serious traumatic disease of the central nervous system,and there is currently no effective treatment for SCI because of its complicated pathophysiology.Bone marrow mesenchymal stem cells(BMSCs)have multidirectional differentiation abilities.Our study aims to explore the effects of bone morphogenetic protein 7(BMP-7)-modified BMSCs transplantation on the repair of SCI in rats.Methods:In this study,a rat spinal cord injury model was established with the modified Allen method.Then,BMSCs transfected with the BMP7 gene were transplanted to treat the spinal cord injury in rats.Forty Sprague-Dawley rats were randomly divided into the sham operation group(sham group),spinal cord injury group(model group),BMSC treatment group(BMSC group)and LV-BMP7-BMSC treatment group(LV-BMP7-BMSC group).The Basso,Beattie,and Bresnahan(BBB)score was used to evaluate the recovery of hindlimb function in the rats.The levels of neurofilament protein NF-200(NF-200)and glial fibrillary acidic protein(GFAP)were detected by immunofluorescence,RT-PCR and Western blotting.Results:At 14 d,21 d,and 28 d after treatment,the BBB score of the rats in the LV-BMP7-BMSC group was higher than that of the rats in the model group and BMSC group.The results showed that NF-200 was expressed at the local spinal cord injury site.Compared with that of the sham group,the NF-200 expression level of the BMSC group and LV-BMP7-BMSC group was increased(P<0.05).The results showed that the mRNA expression levels of NF-200 in the spinal cord tissue of the BMSC group and LV-BMP7-BMSC group were increased compared with those of the sham group(P<0.05).The western blotting results further confirmed the PCR results.Conclusion:BMP-7 gene-modified BMSC transplantation can promote the repair of spinal cord functions after SCI in rats.
基金Key Rearch and Development projects in Shaanxi Province(2019SF-084).
文摘Objective:To investigate the effect ofα1-antitrypsin combined with bone marrow mesenchymal stem cells on retinopathy in diabetic rats and its mechanism.Methods:A model of diabetic retinopathy was established by intraperitoneal injection of streptozotocin.The 30 Wistar rats successfully modeled were randomly divided into a model group,a bone marrow mesenchymal stem cell group and a combined group(α1-antitrypsin combined with bone marrow Mesenchymal stem cells),the blood glucose and serum insulin levels of diabetic rats were measured 4 weeks after treatment.Enzyme-linked immunosorbent assay(ELISA)for measuring serum inflammatory factors IL-1β,IL-6 and TNF-α in rats.Observing the pathological morphology of rat retina under hematoxylin-eosin staining(HE).TUNEL staining to observe the apoptosis of rat retinal nerve cells.Immunohistochemical method to detect the expression level of CD45 in retinal tissue.Real-time fluorescence quantitative PCR was used to detect the expression of retinal vascular endothelial growth factor(VEGF),hypoxiainducible factor-1α(HIF-1α),and angiotensinⅡ(ANGⅡ)mRNA.Western blot was used to detect the expression of p38 MAPK/NF-κB signaling pathway-related proteins in the retinal tissue of each group of rats.Results:Compared with the control group,the rats in the model group had increased blood glucose,decreased insulin levels,increased serum IL-1β,IL-6,and TNF-α levels,and had obvious lesions in the retina.CD45 showed high expression in retinal tissue,VEGF,HIF-1α,ANGⅡ mRNA expression increased,p-p38,p-p65,p-IκBα protein expression increased(P<0.05).Compared with the model group,the bone marrow mesenchymal stem cell group and the combined group have decreased blood glucose,increased insulin levels,and decreased serum IL-1β,IL-6 and TNF-α levels.Retinopathy is improved,apoptosis of retinal nerve cells is reduced,CD45 expression in retinal tissue is reduced,VEGF,HIF-1α,ANGⅡ mRNA expression is decreased,and p-p38,p-p65,p-IκBα protein expression is decreased.Compared with the bone marrow mesenchymal stem cell group,the effect of the combined group was more obvious(P<0.05).Conclusion:α1-antitrypsin combined with bone marrow mesenchymal stem cell transplantation can improve the degree of retinopathy in diabetic rats.The mechanism may be related to the inhibition of p38 MAPK/NF-κB signaling pathway.
文摘Objective To investigate the effects and mechanism of calcitonin gene-related peptide(CGRP)and substance P (SP) on proliferation of rat bone marrow mesenchymal stem cells.Methods The rBMSCs were isolated using whole bone marrow
文摘Objective To study the effect and mechanism of neurological function recovery in rats with spinal cord injury ( SCI) rats after transplantation of neural stem cells which are directly differentiated from bone marrow mesenchymal stem cells ( BMSC ) ,and to investigate the suitable engraftment time. Methods BMSC at 3rd passage were differentiated into neural stem cells ( NSC) , and immunofluorescence staining was used to
文摘BACKGROUND Bone marrow mesenchymal stem cells(BMSCs)are capable of shifting the microglia/macrophages phenotype from M1 to M2,contributing to BMSCsinduced brain repair.However,the regulatory mechanism of BMSCs on microglia/macrophages after ischemic stroke is unclear.Recent evidence suggests that mesencephalic astrocyte-derived neurotrophic factor(MANF)and plateletderived growth factor-AA(PDGF-AA)/MANF signaling regulate M1/M2 macrophage polarization.AIM To investigate whether and how MANF or PDGF-AA/MANF signaling influences BMSCs-mediated M2 polarization.METHODS We identified the secretion of MANF by BMSCs and developed transgenic BMSCs using a targeting small interfering RNA for knockdown of MANF expression.Using a rat middle cerebral artery occlusion(MCAO)model transplanted by BMSCs and BMSCs-microglia Transwell coculture system,the effect of BMSCsinduced downregulation of MANF expression on the phenotype of microglia/macrophages was tested by Western blot,quantitative reverse transcription-polymerase chain reaction,and immunofluorescence.Additionally,microglia were transfected with mimics of miR-30a*,which inuenced expression of X-box binding protein(XBP)1,a key transcription factor that synergized with activating transcription factor 6(ATF6)to govern MANF expression.We examined the levels of miR-30a*,ATF6,XBP1,and MANF after PDGF-AA treatment in the activated microglia.RESULTS Inhibition of MANF attenuated BMSCs-induced functional recovery and decreased M2 marker production,but increased M1 marker expression in vivo or in vitro.Furthermore,PDGF-AA treatment decreased miR-30a*expression,had no influence on the levels of ATF6,but enhanced expression of both XBP1 and MANF.CONCLUSION BMSCs-mediated MANF paracrine signaling,in particular the PDGF-AA/miR-30a*/XBP1/MANF pathway,synergistically mediates BMSCs-induced M2 polarization.
基金National Natural Science Foundation of China(Grant No.81802151)Shandong Province Natural Science Foundation(Grant No.ZR2019MH012)+2 种基金China Post-doctoral Science Foundation(Grant No.2018M642616)Qingdao Applied Foundational Research Youth Project(Grant No.19-6-2-55-cg)Qingdao Traditional Chinese Medicine Science and Technology Project(Grant No.2021-zyym28)
文摘Background:Perturbations in bone marrow mesenchymal stem cell(BMSC)differentiation play an important role in steroid-induced osteonecrosis of the femoral head(SONFH).At present,studies on SONFH concentrate upon the balance within BMSC osteogenic and adipogenic differentiation.However,BMSC apoptosis as well as proliferation are important prerequisites in their differentiation.The hedgehog(HH)signaling pathway regulates bone cell apoptosis.Baicalin(BA),a well-known compound in traditional Chinese medicine,can affect the proliferation and apoptosis of numerous cell types via HH signaling.However,the potential role and mechanisms of BA on BMSCs are unclear.Thus,we aimed to explore the role of BA in dexamethasone(Dex)-induced BMSC apoptosis in this study.Methods:Primary BMSCs were treated with 10-6 mol/L Dex alone or with 5.0μmol/L,10.0μmol/L,or 50.0μmol/L BA for 24 hours followed by co-treatment with 5.0μmol/L,10.0μmol/L,or 50.0μmol/L BA and 10-6 mol/L Dex.Cell viability was assayed through the Cell Counting Kit-8(CCK-8).Cell apoptosis was evaluated using Annexin V-fluorescein isothiocyanate/propidium iodide(PI)staining followed by flow cytometry.The imaging and counting,respectively,of Hochest 33342/PI-stained cells were used to assess the morphological characteristics and proportion of apoptotic cells.To quantify the apoptosis-related proteins(e.g.,apoptosis regulator BAX[Bax],B-cell lymphoma 2[Bcl-2],caspase-3,and cleaved caspase-3)and HH signaling pathway proteins,western blotting was used.A HH-signaling pathway inhibitor was used to demonstrate that BA exerts its anti-apoptotic effects via the HH signaling pathway.Results:The results of CCK-8,Hoechst 33342/PI-staining,and flow cytometry showed that BA did not significantly promote cell proliferation(CCK-8:0μmol/L,100%;2.5μmol/L,98.58%;5.0μmol/L,95.18%;10.0μmol/L,98.11%;50.0μmol/L,99.38%,F=2.33,P>0.05),but it did attenuate the effect of Dex on apoptosis(Hoechst 33342/PI-staining:Dex+50.0μmol/L BA,12.27%vs.Dex,39.27%,t=20.62;flow cytometry:Dex+50.0μmol/L BA,12.68%vs.Dex,37.43%,t=11.56;Both P<0.05).The results of western blotting analysis showed that BA reversed Dex-induced apoptosis by activating the HH signaling pathway,which down-regulated the expression of Bax,cleaved-caspase 3,and suppressor of fused(SUFU)while up-regulating Bcl-2,sonic hedgehog(SHH),and zinc finger protein GLI-1(GLI-1)expression(Bax/Bcl-2:Dex+50.0μmol/L BA,1.09 vs.Dex,2.76,t=35.12;cleaved caspase-3/caspase-3:Dex+50.0μmol/L BA,0.38 vs.Dex,0.73,t=10.62;SHH:Dex+50.0μmol/L BA,0.50 vs.Dex,0.12,t=34.01;SUFU:Dex+50.0μmol/L BA,0.75 vs.Dex,1.19,t=10.78;GLI-1:Dex+50.0μmol/L BA,0.40 vs.Dex,0.11,t=30.68.All P<0.05).Conclusions:BA antagonizes Dex-induced apoptosis of human BMSCs by activating the HH signaling pathway.It is a potential candidate for preventing SONFH.
文摘Mesenchymalstemcells(MSCs)areidealcandidatesfortreatingmanycardiovasculardiseases.MSCscanmodify the internal cardiac microenvironment to facilitate their immunomodulatory and differentiation abilities,which are essential to restore heart function.MSCs can be easily isolated from different sources,including bone marrow,adipose tissues,umbilical cord,and dental pulp.MSCs from various sources differ in their regenerative and therapeutic abilities for cardiovascular disorders.In this review,we will summarize the therapeutic potential of each MSC source for heart diseases and highlight the possible molecular mechanisms of each source to restore cardiac function.
