The periodontal ligament-derived mesenchymal stem cell is regarded as a source of adult stem cells due to its multipotency. However, the proof of chondrogenic potential of the cells is scarce. Therefore, we investigat...The periodontal ligament-derived mesenchymal stem cell is regarded as a source of adult stem cells due to its multipotency. However, the proof of chondrogenic potential of the cells is scarce. Therefore, we investigated the chondrogenic differentiation capacity of periodontal ligament derived mesenchymal stem cells induced by transforming growth factor （TGF）-β3 and bone morphogenetic protein （BMP）-6. After isolation of periodontal ligament stem cells （PDLSCs） from human periodontal ligament, the cells were cultured in Dulbecco＇s modified Eagle＇s medium （DMEM） with 20% fetal bovine serum （FBS）. A mechanical force initiated chondrogenic differentiation of the cells. For chondrogenic differentiation, 10 μg ·L-1 TGF-β3 or 100 μg ·L-1 BMP-6 and the combination treating group for synergistic effect of the growth factors. We analyzed the PDLSCs by fluorescence-activated cell sorting and chondrogenesis were evaluated by glycosaminoglycans assay, histology, immunohistochemistry and genetic analysis. PDLSCs showed mesenchymal stem cell properties proved by FACS analysis. Glycosaminoglycans contents were increased 217% by TGF-β3 and 220% by BMP-6. The synergetic effect of TGF-β3 and BMP-6 were shown up to 281% compared to control. The combination treatment increased Sox9, aggrecan and collagen II expression compared with not only controls, but also TGF-β3 or BMP-6 single treatment dramatically. The histological analysis also indicated the chondrogenic differentiation of PDLSCs in our conditions. The results of the present study demonstrate the potential of the dental stem cell as a valuable cell source for chondrogenesis, which may be applicable for regeneration of cartilage and bone fracture in the field of cell therapy.展开更多
AIM To systematically review the results of studies looking at autologous matrix-induced chondrogenesis(AMIC) in humans. METHODS A literature search was performed, adhering to the PRISMA guidelines, to review any stud...AIM To systematically review the results of studies looking at autologous matrix-induced chondrogenesis(AMIC) in humans. METHODS A literature search was performed, adhering to the PRISMA guidelines, to review any studies using such techniques in humans. Our initial search retrieved 297 articles listed on MEDLINE, Google Scholar, CINHal and EMBASE. From these studies, 15 studies meeting the eligibility criteria were selected and formed the basis of our systematic review.RESULTS The study designs, surgical techniques and outcome measures varied between the studies. Although all studies reported improvements in patient outcome measures, this was not necessarily correlated with magnetic resonance imaging findings. Although there were many additional procedures performed, when AMIC was performed in isolation, the results tended to peak at 24 mo before declining. CONCLUSION Although short-term studies suggest improved patient reported outcomes with a variety of scaffolds, surgical techniques and rehabilitation regimes, the literature remains equivocal on whether the defect size and location, and patient factors affect the outcome. Patientbenefit appears to be maintained in the short-tomedium term but more high level studies with extensive and robust validated outcome measures should be conducted to evaluate the medium-and long-term effect of the AMIC procedure.展开更多
This study evaluated chondrogenesis within a nanofiber polymeric scaffold seeded with isolated untreated chondrocytes, isolated chondrocytes genetically engineered with adenoviral (Ad) bone morphogenetic protein (BMP)...This study evaluated chondrogenesis within a nanofiber polymeric scaffold seeded with isolated untreated chondrocytes, isolated chondrocytes genetically engineered with adenoviral (Ad) bone morphogenetic protein (BMP)-2, or isolated chondrocytes genetically engineered with green fluorescent protein (Ad-GFP). Electrospun polycaprolactone scaffolds (150-200 m thickness, 700 m fiber diameter, 30 m pore size) were optimally seeded with 1 x 107 isolated chondrocytes by using a 20% serum gradient culture system. Chondrocyte-scaffold constructs (untreated, Ad-B- MP-2 and Ad-GFP) were generated from 5 adult horses, cultured in triplicate for 7 or 14 days, and quantitatively analyzed for cell proliferation (DNA content;Hoechst assay), viability, morphology (confocal microscopy), matrix production (proteoglycan content;DMMB assay), and mRNA expression of collagen I, collagen II, and aggrecan. Chondrocytes transduced with Ad-BMP-2 demonstrated greater cell numbers and significantly greater expression of chondrogenic markers including aggrecan, collagen II, and proteoglycan through 14 days of culture as compared to untransduced or Ad-GFP controls. This study demons- trated that chondrocytes can be driven to seed a polycaprolactone nanofiber scaffold by serum gradient and a polycaprolactone nanofiber scaffold containing Ad-BMP2 transduced chondrocytes resulted in grea- ter and accelerated chondrogenesis than controls. This cell engineered construct has potential use in one-step cartilage repair in vivo.展开更多
A new type of TGF-β3 fusion protein with targeted therapy function was constructed,and its feasibility and target specificity of inducing chondrogenesis were investigated by transfecting LAP-MMP-mTGF-β3 gene into ad...A new type of TGF-β3 fusion protein with targeted therapy function was constructed,and its feasibility and target specificity of inducing chondrogenesis were investigated by transfecting LAP-MMP-mTGF-β3 gene into adipose-derived stem cells (ADSCs).The recombinant pIRESEGFP-MMP was constructed by inserting the sense and antisense DNA of encoding the amino acid of the synthetic MMP enzyme cutting site into the eukaryotic expression vector pIRES-EGFP.LAP and mTGF-β3 fragments were obtained by using RT-PCR and inserted into the upstream and downstream of MMP from pIRES-EGFP-MMP respectively,and the recombinant plasmid of pIRES-EGFPLAP-MMP-mTGF-β3 was constructed,which was transferred to ADSCs.The ADSCs were cultured and divided in three groups:experimental group (MMP group),negative control group (no MMP) and non-transfection group.The morphological changes were observed microscopically,and the expression of proteoglycan and type Ⅱ collagen (ColⅡ) was detected by using Alcian blue staining and immunohistochemistry staining at 7th,14th and 21st day after culture.The recombinant plasmid of pIRES-EGFP-LAP-MMP-mTGF-β3 was correctly constructed by methods of enzyme cutting and sequencing analysis.The mTGF-β3 fusion protein was successfully expressed after transfection,and in the presence of the MMP,active protein mTGF-β3 was generated,which significantly promoted differentiation of ADSCs into chondrocytes and the expression of cartilage matrix.The novel fusion protein LAP-MMP-mTGF-β3 can targetedly induce differentiation of ADSCs into chondrocytes,which would open up prospects for target therapy of cartilage damage repair in future.展开更多
Defects of articular cartilage present a unique clinical challenge due to its poor self-healing capacity and avascular nature.Current surgical treatment options do not ensure consistent regeneration of hyaline cartila...Defects of articular cartilage present a unique clinical challenge due to its poor self-healing capacity and avascular nature.Current surgical treatment options do not ensure consistent regeneration of hyaline cartilage in favor of fibrous tissue.Here,we review the current understanding of the most important biological regulators of chondrogenesis and their interactions,to provide insight into potential applications for cartilage tissue engineering.These include various signaling pathways,including fibroblast growth factors(FGFs),transforming growth factor b(TGF-b)/bone morphogenic proteins(BMPs),Wnt/b-catenin,Hedgehog,Notch,hypoxia,and angiogenic signaling pathways.Transcriptional and epigenetic regulation of chondrogenesis will also be discussed.Advances in our understanding of these signaling pathways have led to promising advances in cartilage regeneration and tissue engineering.展开更多
Articular cartilage,which is mainly composed of collagen Ⅱ,enables smooth skeletal movement.Degeneration of collagen Ⅱ can be caused by various events,such as injury,but degeneration especially increases over the co...Articular cartilage,which is mainly composed of collagen Ⅱ,enables smooth skeletal movement.Degeneration of collagen Ⅱ can be caused by various events,such as injury,but degeneration especially increases over the course of normal aging.Unfortunately,the body does not fully repair itself from this type of degeneration,resulting in impaired movement.Microfracture,an articular cartilage repair surgical technique,has been commonly used in the clinic to induce the repair of tissue at damage sites.Mesenchymal stem cells(MSC)have also been used as cell therapy to repair degenerated cartilage.However,the therapeutic outcomes of all these techniques vary in different patients depending on their age,health,lesion size and the extent of damage to the cartilage.The repairing tissues either form fibrocartilage or go into a hypertrophic stage,both of which do not reproduce the equivalent functionality of endogenous hyaline cartilage.One of the reasons for this is inefficient chondrogenesis by endogenous and exogenous MSC.Drugs that promote chondrogenesis could be used to induce self-repair of damaged cartilage as a non-invasive approach alone,or combined with other techniques to greatly assist the therapeutic outcomes.The recent development of human induced pluripotent stem cell(iPSCs),which are able to self-renew and differentiate into multiple cell types,provides a potentially valuable cell resource for drug screening in a“more relevant”cell type.Here we report a screening platform using human iPSCs in a multi-well plate format to identify compounds that could promote chondrogenesis.展开更多
Extracellular matrix(ECM)-based biomaterials are promising candidates in cartilage tissue engineering by simulating the native microenvironment to regulate the chondrogenic differentiation of bone marrow mesenchymal s...Extracellular matrix(ECM)-based biomaterials are promising candidates in cartilage tissue engineering by simulating the native microenvironment to regulate the chondrogenic differentiation of bone marrow mesenchymal stem cells(BMSCs)without exogenous growth factors.The biological properties of ECM scaffolds are primarily depended on the original source,which would directly influence the chondrogenic effects of the ECM materials.Despite the expanding investigations on ECM scaffolds in recent years,the selection of optimized ECM materials in cartilage regeneration was less reported.In this study,we harvested and compared the articular cartilage ECM from newborn,juvenile and adult rabbits.The results demonstrated the significant differences in the mechanical strength,sulphated glycosaminoglycan and collagen contents of the different aged ECM,before and after decellularization.Consequently,different compositional and mechanical properties were shown in the three ECM-based collagen hydrogels,which exerted age-dependent chondrogenic inducibility.In general,both in vitro and in vivo results suggested that the newborn ECM promoted the most chondrogenesis of BMSCs but led to severe matrix calcification.In contrast,BMSCs synthesized the lowest amount of cartilaginous matrix with minimal calcification with adult ECM.The juvenile ECM achieved the best overall results in promoting chondrogenesis of BMSCs and preventing matrix calcification.Together,this study provides important information to our current knowledge in the design of future ECM-based biomaterials towards a successful repair of articular cartilage.展开更多
Treatment of physeal fractures(15%–30%of all paediatric fractures)remains a challenge as in approximately 10%of the cases,significant growth disturbance may occur.Bioresorbable Magnesium-based implants represent a st...Treatment of physeal fractures(15%–30%of all paediatric fractures)remains a challenge as in approximately 10%of the cases,significant growth disturbance may occur.Bioresorbable Magnesium-based implants represent a strategy to minimize damage(i.e.,load support until bone healing without second surgery).Nevertheless,the absence of harmful effects of magnesium-implants and their degradation products on the growth plate should be confirmed.Here,the proteome of human mesenchymal stem cells undergoing chondrogenesis was evaluated when exposed to the products of various Magnesium-based materials degradation.The results of this study indicate that the materials induced regulation of proteins associated with cell chondrogenesis and cartilage formation,which should be beneficial for cartilage regeneration.展开更多
Although cartilage tissue engineering has been developed for decades, it is still unclear whether angiogenesis was the accompaniment of chondrogenesis in cartilage regeneration. This study aimed to explore the process...Although cartilage tissue engineering has been developed for decades, it is still unclear whether angiogenesis was the accompaniment of chondrogenesis in cartilage regeneration. This study aimed to explore the process of anti-angiogenesis during cartilage regenerative progress in cartilage repair extracellular matrix(ECM) materials under Hypoxia. C3H10T1/2 cell line, seeded as pellet or in ECM materials, was added with chondrogenic medium or DMEM medium for 21 days under hypoxia or normoxia environment. Genes and mi RNAs related with chondrogenesis and angiogenesis were detected by RT-q PCR technique on Days 7, 14, and 21. Dual-luciferase report system was used to explore the regulating roles of mi RNAs on angiogenesis. Results showed that the chondrogenic medium promotes chondrogenesis both in pellet and ECM materials culture. HIF1α was up-regulated under hypoxia compared with normoxia(P < 0.05). Meanwhile, hypoxia enhanced chondrogenesis. miR-140-5p exhibited higher expression while miR-146 b exhibited lower expression. The chondrogenic phenotype was more stabilized in the ECM materials in chondrogenic medium than DMEM medium, with lower VEGFα expression even under hypoxia.Dual-luciferase report assays demonstrated that mi R-140-5p directly targets VEGFα by binding its 3′-UTR. Taken together, chondrogenic cytokines, ECM materials and hypoxia synergistically promoted chondrogenesis and inhibited angiogenesis. mi R-140-5p played an important role in this process.展开更多
The limited intrinsic healing potential of human articular cartilage is a well-known problem in orthopedic surgery. Thus a variety of surgical techniques have been developed to reduce joint pain, improve joint functio...The limited intrinsic healing potential of human articular cartilage is a well-known problem in orthopedic surgery. Thus a variety of surgical techniques have been developed to reduce joint pain, improve joint function and delay the onset of osteoarthritis. Microfractures as a bone marrow stimulation technique present the most common applied articular cartilage repair procedure today. Unfortunately the deficiencies of fibrocartilaginous repair tissue inevitably lead to breakdown under normal joint loading and clinical results deteriorate with time. To overcome the shortcomings of microfracture, an enhanced microfracture technique was developed with an additional collagen Ⅰ/Ⅲ membrane(Autologous, Matrix-Induced Chondrogenesis, AMIC). This article reviews the pre-clinical rationale of microfractures and AMIC, presents clinical studies and shows the advantages and disadvantages of these widely usedtechniques. PubM ed and the Cochrane database were searched to identify relevant studies. We used a comprehensive search strategy with no date or language restrictions to locate studies that examined the AMIC technique and microfracture. Search keywords included cartilage, microfracture, AMIC, knee, ChondroGide. Besides this, we included our own experiences and study authors were contacted if more and non published data were needed. Both cartilage repair techniques represent an effective and safe method of treating full-thickness chondral defects of the knee in selected cases. While results after microfracture deteriorate with time, mid-term results after AMIC seem to be enduring. Randomized studies with long-term followup are needed whether the grafted area will maintain functional improvement and structural integrity over time.展开更多
基金supported by the Bio & Medical Technology Development Program of the National Research Foundation(NRF) funded by the Korean government(MEST)(No.860-20110087)
文摘The periodontal ligament-derived mesenchymal stem cell is regarded as a source of adult stem cells due to its multipotency. However, the proof of chondrogenic potential of the cells is scarce. Therefore, we investigated the chondrogenic differentiation capacity of periodontal ligament derived mesenchymal stem cells induced by transforming growth factor （TGF）-β3 and bone morphogenetic protein （BMP）-6. After isolation of periodontal ligament stem cells （PDLSCs） from human periodontal ligament, the cells were cultured in Dulbecco＇s modified Eagle＇s medium （DMEM） with 20% fetal bovine serum （FBS）. A mechanical force initiated chondrogenic differentiation of the cells. For chondrogenic differentiation, 10 μg ·L-1 TGF-β3 or 100 μg ·L-1 BMP-6 and the combination treating group for synergistic effect of the growth factors. We analyzed the PDLSCs by fluorescence-activated cell sorting and chondrogenesis were evaluated by glycosaminoglycans assay, histology, immunohistochemistry and genetic analysis. PDLSCs showed mesenchymal stem cell properties proved by FACS analysis. Glycosaminoglycans contents were increased 217% by TGF-β3 and 220% by BMP-6. The synergetic effect of TGF-β3 and BMP-6 were shown up to 281% compared to control. The combination treatment increased Sox9, aggrecan and collagen II expression compared with not only controls, but also TGF-β3 or BMP-6 single treatment dramatically. The histological analysis also indicated the chondrogenic differentiation of PDLSCs in our conditions. The results of the present study demonstrate the potential of the dental stem cell as a valuable cell source for chondrogenesis, which may be applicable for regeneration of cartilage and bone fracture in the field of cell therapy.
文摘AIM To systematically review the results of studies looking at autologous matrix-induced chondrogenesis(AMIC) in humans. METHODS A literature search was performed, adhering to the PRISMA guidelines, to review any studies using such techniques in humans. Our initial search retrieved 297 articles listed on MEDLINE, Google Scholar, CINHal and EMBASE. From these studies, 15 studies meeting the eligibility criteria were selected and formed the basis of our systematic review.RESULTS The study designs, surgical techniques and outcome measures varied between the studies. Although all studies reported improvements in patient outcome measures, this was not necessarily correlated with magnetic resonance imaging findings. Although there were many additional procedures performed, when AMIC was performed in isolation, the results tended to peak at 24 mo before declining. CONCLUSION Although short-term studies suggest improved patient reported outcomes with a variety of scaffolds, surgical techniques and rehabilitation regimes, the literature remains equivocal on whether the defect size and location, and patient factors affect the outcome. Patientbenefit appears to be maintained in the short-tomedium term but more high level studies with extensive and robust validated outcome measures should be conducted to evaluate the medium-and long-term effect of the AMIC procedure.
文摘This study evaluated chondrogenesis within a nanofiber polymeric scaffold seeded with isolated untreated chondrocytes, isolated chondrocytes genetically engineered with adenoviral (Ad) bone morphogenetic protein (BMP)-2, or isolated chondrocytes genetically engineered with green fluorescent protein (Ad-GFP). Electrospun polycaprolactone scaffolds (150-200 m thickness, 700 m fiber diameter, 30 m pore size) were optimally seeded with 1 x 107 isolated chondrocytes by using a 20% serum gradient culture system. Chondrocyte-scaffold constructs (untreated, Ad-B- MP-2 and Ad-GFP) were generated from 5 adult horses, cultured in triplicate for 7 or 14 days, and quantitatively analyzed for cell proliferation (DNA content;Hoechst assay), viability, morphology (confocal microscopy), matrix production (proteoglycan content;DMMB assay), and mRNA expression of collagen I, collagen II, and aggrecan. Chondrocytes transduced with Ad-BMP-2 demonstrated greater cell numbers and significantly greater expression of chondrogenic markers including aggrecan, collagen II, and proteoglycan through 14 days of culture as compared to untransduced or Ad-GFP controls. This study demons- trated that chondrocytes can be driven to seed a polycaprolactone nanofiber scaffold by serum gradient and a polycaprolactone nanofiber scaffold containing Ad-BMP2 transduced chondrocytes resulted in grea- ter and accelerated chondrogenesis than controls. This cell engineered construct has potential use in one-step cartilage repair in vivo.
基金supported by the National Natural Science Foundation of China(No.81101376)
文摘A new type of TGF-β3 fusion protein with targeted therapy function was constructed,and its feasibility and target specificity of inducing chondrogenesis were investigated by transfecting LAP-MMP-mTGF-β3 gene into adipose-derived stem cells (ADSCs).The recombinant pIRESEGFP-MMP was constructed by inserting the sense and antisense DNA of encoding the amino acid of the synthetic MMP enzyme cutting site into the eukaryotic expression vector pIRES-EGFP.LAP and mTGF-β3 fragments were obtained by using RT-PCR and inserted into the upstream and downstream of MMP from pIRES-EGFP-MMP respectively,and the recombinant plasmid of pIRES-EGFPLAP-MMP-mTGF-β3 was constructed,which was transferred to ADSCs.The ADSCs were cultured and divided in three groups:experimental group (MMP group),negative control group (no MMP) and non-transfection group.The morphological changes were observed microscopically,and the expression of proteoglycan and type Ⅱ collagen (ColⅡ) was detected by using Alcian blue staining and immunohistochemistry staining at 7th,14th and 21st day after culture.The recombinant plasmid of pIRES-EGFP-LAP-MMP-mTGF-β3 was correctly constructed by methods of enzyme cutting and sequencing analysis.The mTGF-β3 fusion protein was successfully expressed after transfection,and in the presence of the MMP,active protein mTGF-β3 was generated,which significantly promoted differentiation of ADSCs into chondrocytes and the expression of cartilage matrix.The novel fusion protein LAP-MMP-mTGF-β3 can targetedly induce differentiation of ADSCs into chondrocytes,which would open up prospects for target therapy of cartilage damage repair in future.
基金The authors’ laboratories were supported in part byresearch grants from the National Institutes of Health(AR50142, AR054381, and AT004418 to RCH, HHL, and TCH)and Scoliosis Research Society (MJL)JDG and VT were recipientsof the Pritzker Summer Research Fellowship fundedthrough a NIH T-35 training grant (NIDDK)MKM was arecipient of Howard Hughes Medical Institute MedicalResearch Fellowship.
文摘Defects of articular cartilage present a unique clinical challenge due to its poor self-healing capacity and avascular nature.Current surgical treatment options do not ensure consistent regeneration of hyaline cartilage in favor of fibrous tissue.Here,we review the current understanding of the most important biological regulators of chondrogenesis and their interactions,to provide insight into potential applications for cartilage tissue engineering.These include various signaling pathways,including fibroblast growth factors(FGFs),transforming growth factor b(TGF-b)/bone morphogenic proteins(BMPs),Wnt/b-catenin,Hedgehog,Notch,hypoxia,and angiogenic signaling pathways.Transcriptional and epigenetic regulation of chondrogenesis will also be discussed.Advances in our understanding of these signaling pathways have led to promising advances in cartilage regeneration and tissue engineering.
文摘Articular cartilage,which is mainly composed of collagen Ⅱ,enables smooth skeletal movement.Degeneration of collagen Ⅱ can be caused by various events,such as injury,but degeneration especially increases over the course of normal aging.Unfortunately,the body does not fully repair itself from this type of degeneration,resulting in impaired movement.Microfracture,an articular cartilage repair surgical technique,has been commonly used in the clinic to induce the repair of tissue at damage sites.Mesenchymal stem cells(MSC)have also been used as cell therapy to repair degenerated cartilage.However,the therapeutic outcomes of all these techniques vary in different patients depending on their age,health,lesion size and the extent of damage to the cartilage.The repairing tissues either form fibrocartilage or go into a hypertrophic stage,both of which do not reproduce the equivalent functionality of endogenous hyaline cartilage.One of the reasons for this is inefficient chondrogenesis by endogenous and exogenous MSC.Drugs that promote chondrogenesis could be used to induce self-repair of damaged cartilage as a non-invasive approach alone,or combined with other techniques to greatly assist the therapeutic outcomes.The recent development of human induced pluripotent stem cell(iPSCs),which are able to self-renew and differentiate into multiple cell types,provides a potentially valuable cell resource for drug screening in a“more relevant”cell type.Here we report a screening platform using human iPSCs in a multi-well plate format to identify compounds that could promote chondrogenesis.
基金supported by the National Key Research Programme of China(No.2018YFC1105900)the Sichuan Science and Technology Programme(No.2018RZ0039)the 111 Project(No.B16033).
文摘Extracellular matrix(ECM)-based biomaterials are promising candidates in cartilage tissue engineering by simulating the native microenvironment to regulate the chondrogenic differentiation of bone marrow mesenchymal stem cells(BMSCs)without exogenous growth factors.The biological properties of ECM scaffolds are primarily depended on the original source,which would directly influence the chondrogenic effects of the ECM materials.Despite the expanding investigations on ECM scaffolds in recent years,the selection of optimized ECM materials in cartilage regeneration was less reported.In this study,we harvested and compared the articular cartilage ECM from newborn,juvenile and adult rabbits.The results demonstrated the significant differences in the mechanical strength,sulphated glycosaminoglycan and collagen contents of the different aged ECM,before and after decellularization.Consequently,different compositional and mechanical properties were shown in the three ECM-based collagen hydrogels,which exerted age-dependent chondrogenic inducibility.In general,both in vitro and in vivo results suggested that the newborn ECM promoted the most chondrogenesis of BMSCs but led to severe matrix calcification.In contrast,BMSCs synthesized the lowest amount of cartilaginous matrix with minimal calcification with adult ECM.The juvenile ECM achieved the best overall results in promoting chondrogenesis of BMSCs and preventing matrix calcification.Together,this study provides important information to our current knowledge in the design of future ECM-based biomaterials towards a successful repair of articular cartilage.
基金financially supported by the Helmholtz Virtual Institute VH-VI-523(in vivo studies of biodegradable magnesium based implant materials)。
文摘Treatment of physeal fractures(15%–30%of all paediatric fractures)remains a challenge as in approximately 10%of the cases,significant growth disturbance may occur.Bioresorbable Magnesium-based implants represent a strategy to minimize damage(i.e.,load support until bone healing without second surgery).Nevertheless,the absence of harmful effects of magnesium-implants and their degradation products on the growth plate should be confirmed.Here,the proteome of human mesenchymal stem cells undergoing chondrogenesis was evaluated when exposed to the products of various Magnesium-based materials degradation.The results of this study indicate that the materials induced regulation of proteins associated with cell chondrogenesis and cartilage formation,which should be beneficial for cartilage regeneration.
基金supported by the National Basic Research Program of China(973 Program,No.2012CB619100)the National Natural Science Foundation of China(Nos.31430030,0731001,and 81071512)+1 种基金the Natural Science Foundation of Guangdong Province(No.2014A030310466)the China Scholarship Council
文摘Although cartilage tissue engineering has been developed for decades, it is still unclear whether angiogenesis was the accompaniment of chondrogenesis in cartilage regeneration. This study aimed to explore the process of anti-angiogenesis during cartilage regenerative progress in cartilage repair extracellular matrix(ECM) materials under Hypoxia. C3H10T1/2 cell line, seeded as pellet or in ECM materials, was added with chondrogenic medium or DMEM medium for 21 days under hypoxia or normoxia environment. Genes and mi RNAs related with chondrogenesis and angiogenesis were detected by RT-q PCR technique on Days 7, 14, and 21. Dual-luciferase report system was used to explore the regulating roles of mi RNAs on angiogenesis. Results showed that the chondrogenic medium promotes chondrogenesis both in pellet and ECM materials culture. HIF1α was up-regulated under hypoxia compared with normoxia(P < 0.05). Meanwhile, hypoxia enhanced chondrogenesis. miR-140-5p exhibited higher expression while miR-146 b exhibited lower expression. The chondrogenic phenotype was more stabilized in the ECM materials in chondrogenic medium than DMEM medium, with lower VEGFα expression even under hypoxia.Dual-luciferase report assays demonstrated that mi R-140-5p directly targets VEGFα by binding its 3′-UTR. Taken together, chondrogenic cytokines, ECM materials and hypoxia synergistically promoted chondrogenesis and inhibited angiogenesis. mi R-140-5p played an important role in this process.
文摘The limited intrinsic healing potential of human articular cartilage is a well-known problem in orthopedic surgery. Thus a variety of surgical techniques have been developed to reduce joint pain, improve joint function and delay the onset of osteoarthritis. Microfractures as a bone marrow stimulation technique present the most common applied articular cartilage repair procedure today. Unfortunately the deficiencies of fibrocartilaginous repair tissue inevitably lead to breakdown under normal joint loading and clinical results deteriorate with time. To overcome the shortcomings of microfracture, an enhanced microfracture technique was developed with an additional collagen Ⅰ/Ⅲ membrane(Autologous, Matrix-Induced Chondrogenesis, AMIC). This article reviews the pre-clinical rationale of microfractures and AMIC, presents clinical studies and shows the advantages and disadvantages of these widely usedtechniques. PubM ed and the Cochrane database were searched to identify relevant studies. We used a comprehensive search strategy with no date or language restrictions to locate studies that examined the AMIC technique and microfracture. Search keywords included cartilage, microfracture, AMIC, knee, ChondroGide. Besides this, we included our own experiences and study authors were contacted if more and non published data were needed. Both cartilage repair techniques represent an effective and safe method of treating full-thickness chondral defects of the knee in selected cases. While results after microfracture deteriorate with time, mid-term results after AMIC seem to be enduring. Randomized studies with long-term followup are needed whether the grafted area will maintain functional improvement and structural integrity over time.
