AIM:To investigate the effects of Sonic hedgehog(Shh)gene-modified bone marrow mesenchymal stem cells(MSCs)on graft-induced retinal gliosis and retinal ganglion cells(RGCs)survival in diabetic mice.METHODS:Bone marrow...AIM:To investigate the effects of Sonic hedgehog(Shh)gene-modified bone marrow mesenchymal stem cells(MSCs)on graft-induced retinal gliosis and retinal ganglion cells(RGCs)survival in diabetic mice.METHODS:Bone marrow-derived MSCs were genetically modified with the Shh gene to generate a stably transfected cell line of Shh-modified MSCs(MSC-Shh).Intravitreal injections of MSC-Shh and green fluorescent protein-modified MSCs(MSC-Gfp;control)were administered in diabetic mice.After 4wk,the effects of MSC-Shh on retinal gliosis were evaluated using fundus photography,and markers of gliosis were examined by immunofluorescence and Western blotting.The neurotrophic factors expression and RGCs survival in the host retina were evaluated using Western blotting and immunofluorescence.The mechanisms underlying the effects of MSC-Shh was investigated.RESULTS:A significant reduction of proliferative vitreoretinopathy(PVR)was observed after intravitreal injection of MSC-Shh compared to MSC-Gfp.Significant downregulation of glial fibrillary acidic protein(GFAP)was demonstrated in the host retina after MSC-Shh administration compared to MSC-Gfp.The extracellular signal-regulated kinase 1/2(ERK1/2),protein kinase B(AKT)and phosphatidylin-ositol-3-kinase(PI3K)pathways were significantly downregulated after MSC-Shh administration compared to MSC-Gfp.Brain-derived neurotrophic factor(BDNF)and ciliary neurotrophic factor(CNTF)levels were significantly increased in the host retina,and RGCs loss was significantly prevented after MSC-Shh administration.CONCLUSION:MSC-Shh administration reduces graft-induced reactive gliosis following intravitreal injection in diabetic mice.The ERK1/2,AKT and PI3K pathways are involved in this process.MSC-Shh also increases the levels of neurotrophic factors in the host retina and promoted RGCs survival in diabetic mice.展开更多
Glaucoma,characterized by a degenerative loss of retinal ganglion cells,is the second leading cause of blindness worldwide.There is currently no cure for vision loss in glaucoma because retinal ganglion cells do not r...Glaucoma,characterized by a degenerative loss of retinal ganglion cells,is the second leading cause of blindness worldwide.There is currently no cure for vision loss in glaucoma because retinal ganglion cells do not regenerate and are not replaced after injury.Human stem cell-derived retinal ganglion cell transplant is a potential therapeutic strategy for retinal ganglion cell degenerative diseases.In this review,we first discuss a 2D protocol for retinal ganglion cell differentiation from human stem cell culture,including a rapid protocol that can generate retinal ganglion cells in less than two weeks and focus on their transplantation outcomes.Next,we discuss using 3D retinal organoids for retinal ganglion cell transplantation,comparing cell suspensions and clusters.This review provides insight into current knowledge on human stem cell-derived retinal ganglion cell differentiation and transplantation,with an impact on the field of regenerative medicine and especially retinal ganglion cell degenerative diseases such as glaucoma and other optic neuropathies.展开更多
The accumulation of excessive reactive oxygen species can exacerbate any injury of retinal tissue because free radicals can trigger lipid peroxidation,protein damage and DNA fragmentation.Increased oxidative stress is...The accumulation of excessive reactive oxygen species can exacerbate any injury of retinal tissue because free radicals can trigger lipid peroxidation,protein damage and DNA fragmentation.Increased oxidative stress is associated with the common pathological process of many eye diseases,such as glaucoma,diabetic retinopathy and ischemic optic neuropathy.Many studies have demonstrated that Lycium barbarum polysaccharides(LBP)protects against oxidative injury in numerous cells and tissues.For the model of hypoxia we used cultured retinal ganglion cells and induced hypoxia by incubating with 200μM cobalt chloride(CoCl2)for 24 hours.To investigate the protective effect of LBP and its mechanism of action against oxidative stress injury,the retinal tissue was pretreated with 0.5 mg/mL LBP for 24 hours.The results of flow cytometric analysis showed LBP could effectively reduce the CoCl2-induced retinal ganglion cell apoptosis,inhibited the generation of reactive oxygen species and the reduction of mitochondrial membrane potential.These findings suggested that LBP could protect retinal ganglion cells from CoCl2-induced apoptosis by reducing mitochondrial membrane potential and reactive oxygen species.展开更多
AIM: To explore the effect of ciliary neurotrophic factor(CNTF) on retinal ganglion cell(RGC)-5 induced by hydrogen peroxide(H_2O_2). METHODS: After cell adherence, RGC-5 culture medium was changed to contain differen...AIM: To explore the effect of ciliary neurotrophic factor(CNTF) on retinal ganglion cell(RGC)-5 induced by hydrogen peroxide(H_2O_2). METHODS: After cell adherence, RGC-5 culture medium was changed to contain different concentrations of H_2O_2 from50 to 150 μmol/L at four time points(0.5, 1, 1.5 and 2 h) to select the concentration and time point for H_2O_2 induced model. Two different ways of interventions for injured RGC-5 cells respectively were CNTF as an addition in the culture medium or recombinant lentiviral plasmid carrying CNTF gene transfecting bone mesenchymal stem cells(BMSCs) for co-culture with RGC-5. RESULTS: Compared to the control group, H_2O_2 led to RGC-5 death closely associated with concentrations and action time of H_2O_2 and we chose 125 μmol/L and 2 h to establish the H_2O_2-induced model. While CNTF inhibited the loss of RGC-5 cells obviously with a dose-dependent survival rate. Nevertheless two administration routes had different survival rate yet higher rate in recombinant lentiviral plasmid group but there were no statistically significant differences. CONCLUSION: Both the two administration routes of CNTF have effects on RGC-5 cells induced by H_2O_2. If their own advantages were combined, there may be a better administration route.展开更多
AIM: To explore if ischemic preconditioning(IPC) can enhance the survival of retinal ganglion cells(RGCs) after optic nerve axotomy. METHODS: Twenty-four hours prior to retinal ischemia 60 min or axotomy, IPC was appl...AIM: To explore if ischemic preconditioning(IPC) can enhance the survival of retinal ganglion cells(RGCs) after optic nerve axotomy. METHODS: Twenty-four hours prior to retinal ischemia 60 min or axotomy, IPC was applied for ten minutes in groups of(n=72) animals. The survival of RGCs, the cellular expression of heat shock protein 27(HSP27) and heat shock protein 70(HSP70) and the numbers of retinal microglia in the different groups were quantified at 7 and 14 d post-injury. The cellular expression of HSP27 and HSP70 and changes in the numbers of retinal microglia were quantified to detect the possible mechanism of the protection of the IPC. RESULTS: Ten minutes of IPC promoted RGC survival in both the optic nerve injury(IPC-ONT) and the retinal ischemia 60min(IPC-IR60) groups, examined at 7d and 14 d post-injury. Microglial proliferation showed little correlation with the extent of benefit effects of IPC on the rescue of RGCs. The number of HSP27-positive RGCs was significantly higher in the IPC-ONT group than in the sham IPC-ONT group, although the percentage of HSP27-positive RGCs did not significantly differ between groups. For the IPC-IR60 group, neither the number nor the percentage of the HSP27-positive RGCs differed significantly between the IPC and the sham-operated groups. The number of HSP70-positive RGCs was significantly higher for both the IPC-ONT and the IPC-IR60 experimental groups, but the percentages did not differ. CONCLUSION: The induction of IPC enhances the survival of RGCs against both axotomy and retinal ischemia.展开更多
BACKGROUND:Previous studies have shown that nerve regeneration factor (NRF) provides neuroprotective effects. However,the neuroprotective effects on retinal ganglion cells in an animal model of glaucoma remain uncerta...BACKGROUND:Previous studies have shown that nerve regeneration factor (NRF) provides neuroprotective effects. However,the neuroprotective effects on retinal ganglion cells in an animal model of glaucoma remain uncertain. OBJECTIVE:To determine the neuroprotective effects of NRF on retinal ganglion cells in a rabbit model of acute hyper-intraocular pressure and to compare the effects on brain-derived neurotrophic factor (BDNF). DESIGN,TIME AND SETTING:A randomized,controlled,animal experiment was performed at Jiangsu Provincial Key Laboratory of Neural Regeneration from September 2006 to August 2007. MATERIALS:Sterone,a major component of NRF,was provided by the Key Laboratory of Neural Regeneration,Nantong University in China; BDNF was provided by BioDesign Inc.,USA. METHODS:A total of 24 healthy rabbits were randomly assigned to NRF,BDNF,and phosphate buffered saline groups,with 8 rabbits per group. The left eyes were considered normal controls,and acute hyper-intraocular pressure was induced in the right eyes via anterior chamber perfusion. The right camera vitrea bulbi was injected with 4.5 μg NRF,3.75 μg BDNF,or 5 μL 0.1 mol/L phosphate buffered saline,respectively. MAIN OUTCOME MEASURES:Retinal ganglion cells were reverse-labeled using horseradish peroxidase to quantify cell density at 2,4,and 6 mm from the optic disc edge. RESULTS:NRF increased the number of surviving retinal ganglion cells at the optic disc edge (P < 0.01 or P < 0.05). The density of surviving retinal ganglion cells decreased with increasing distance from the optic disc. The number of retinal ganglion cells in the BDNF group was similar to the NRF group (P > 0.05). At 2,4,and 6 mm away from the optic disc edge,there was no significant difference in retinal ganglion cell density between NRF and BDNF groups (P > 0.05). CONCLUSION:NRF provided protection to retinal ganglion cells in a rabbit model of acute hyper-intraocular pressure,i.e.,NRF enhanced the survival rate of retinal ganglion cells. The neuroprotective effect was similar to BDNF.展开更多
The mammalian retina displays incomplete intrinsic regenerative capacities;therefore,retina degeneration is a major cause of irreversible blindness such as glaucoma,agerelated macular degeneration and diabetic retinop...The mammalian retina displays incomplete intrinsic regenerative capacities;therefore,retina degeneration is a major cause of irreversible blindness such as glaucoma,agerelated macular degeneration and diabetic retinopathy.These diseases lead to the loss of retinal cells and serious vision loss in the late stage.Stem cell transplantation is a great promising novel treatment for these incurable retinal degenerative diseases and represents an exciting area of regenerative neurotherapy.Several suitable stem cell sources for transplantation including human embryonic stem cells,induced pluripotent stem cells and adult stem cells have been identified as promising target populations.However,the retina is an elegant neuronal complex composed of various types of cells with different functions.The replacement of these different types of cells by transplantation should be addressed separately.So far,retinal pigment epithelium transplantation has achieved the most advanced stage of clinical trials,while transplantation of retinal neurons such as retinal ganglion cells and photoreceptors has been mostly studied in pre-clinical animal models.In this review,we opine on the key problems that need to be addressed before stem cells transplantation,especially for replacing injured retinal ganglion cells,may be used practically for treatment.A key problem we have called the Switchboard Dilemma is a major block to have functional retinal ganglion cell replacement.We use the public switchboard telephone network as an example to illustrate different difficulties for replacing damaged components in the retina that allow for visual signaling.Retinal ganglion cell transplantation is confronted by significant hurdles,because retinal ganglion cells receive signals from different interneurons,integrate and send signals to the correct targets of the visual system,which functions similar to the switchboard in a telephone network-therefore the Switchboard Dilemma.展开更多
AIM:To observe the protective effect of human umbilical cord mesenchymal stem cells(huc MSCs)on retinal ganglion cel s(RGCs)injury in mice with acute ocular hypertension(AOH).METHODS:Fifty-six adult male C57 BL/6 mice...AIM:To observe the protective effect of human umbilical cord mesenchymal stem cells(huc MSCs)on retinal ganglion cel s(RGCs)injury in mice with acute ocular hypertension(AOH).METHODS:Fifty-six adult male C57 BL/6 mice were randomly divided into four groups:normal group,AOH group,huc MSCs group,normal saline(NS)group.Left eye of mice was induced by 90 mm Hg intraocular pressure for 1 h to establish AOH model.huc MSCs 1×105/μL,1μL or NS 1μL was injected into the vitreous body the next day.CMDil fluorescent dye was used to label the 3 rd generation of huc MSCs,for tracing the cells in the vitreous cavity of mice.Seven days after the model established,hematoxylin-eosin(HE)staining was used to observe the thickness of the inner retina layer in four groups.Numbers and loss rate of RGCs were evaluated by counting Brn-3 a positive cells stained by immunofluorescencein.RESULTS:On the 7 th day after AOH established,labeled huc MSCs were found in the vitreous cavity.HE staining showed that the thickness of retinal inner layer in AOH group was significantly lower than that in normal group and huc MSCs group(P<0.05),same as that in NS group(P>0.05).Compared with AOH group,the RGCs in normal group was significantly higher;RGCs number increased in huc MSCs group and the loss rate was lower(P<0.05).Injection of NS had no protective effect on RGCs.CONCLUSION:In AOH mouse model,vitreous injection of hucMSCs have shown a protection for RGCs.展开更多
AIM:To investigate the role of Brn-3b in differentiation process of stem cells derived from retinal Miiller cells into the ganglion cell.METHODS:The passage culture method of Miiller cells from retina of newborn Sprag...AIM:To investigate the role of Brn-3b in differentiation process of stem cells derived from retinal Miiller cells into the ganglion cell.METHODS:The passage culture method of Miiller cells from retina of newborn Sprague Dawley rats was carried out by repeated incomplete pancreatic enzyme digestion method.The cells were detected by fluorescenceactivated cell sorter(FACS),immunohistochemistry technology and reverse transcription-polymerase chain reaction(RT-PCR) to determine the purity.The third passage of cells was induced in the serum-free dedifferentiation medium.The expression of the specific markers Ki-67 and nestin of retinal stem cells was measured by RT-PCR and Western blot.The cell proliferation of retinal stem cells was detected by 5-Ethynyl-2'-deoxyuridine(Edu) staining.The cells were randomly divided into 5 groups as follows:group A:Brn-3bsiRNA group;group B:Brn-3b control siRNA group;group C:pGC-Brn-3b-green fluorescent protein(GFP) group;group D:pGC-GFP group;group E:control group(without any handling).The purified Muller cells were cultured for 3-7d,then,the percentage of ganglion cells was counted by immunofluorescence staining.RESULTS:FACS demonstrated the purity of retinal Muller cells was more 97.44%.A few spherical cell spheres appeared.Immunofluorescence staining showed that stem cells within the spheres were positive for retinal stem cell-specific markers nestin(red fluorescence,92.94%±6.48%) and Ki-67(green fluorescence,85.96%±6.04%).Meanwhile,RT-PCR analysis showed cell spheres in the culture to have expressed a battery of transcripts characteristic of stem cells such as nestin and Ki-67,which were absent in the Muller cells.Western blot analysis further confirmed the expression of nestin and Ki-67 in the cell spheres but not in the Muller cells.Edu staining showed most of the nuclei within the cell spheres were stained red(82.80%±6.65%),suggesting the new cell spheres had the capacity for effective proliferation.The statistics result showed the difference between Brn-3bsiRNA group and Brn-3b control siRNA group or the control group was significant(F=15,P<0.05),while the difference between Brn-3b control siRNA group or the control group was not statistically significant(P>0.05).CONCLUSION:The repeated incomplete pancreatic enzyme digestion method is an efficient and practical method to purify retinal M(u|¨)ller cells.Retinal stem cells were successfully cloned in the dedifferentiational medium.Retinal M(u|¨)ller cells are accessible sources of retinal stem cells.Brn-3b is an important regulatory gene in stem cells differentiated into retinal ganglion cell.展开更多
Human central nerve system(CNS)is an extremely complex and delicate structure.While regeneration is possible in some reptiles and fish CNS,the regeneration capacity seems completely lost in adult mammals.Therefore,the...Human central nerve system(CNS)is an extremely complex and delicate structure.While regeneration is possible in some reptiles and fish CNS,the regeneration capacity seems completely lost in adult mammals.Therefore,the classic concept is that once neurons in mammal展开更多
Retinal ganglion cell(RGC) degeneration is irreversible in glaucoma and tyrosine kinase receptor B(Trk B)-associated signaling pathways have been implicated in the process.In this study,we attempted to examine whether...Retinal ganglion cell(RGC) degeneration is irreversible in glaucoma and tyrosine kinase receptor B(Trk B)-associated signaling pathways have been implicated in the process.In this study,we attempted to examine whether imipramine,a tricyclic antidepressant,may protect hydrogen peroxide(H_2O_2)-induced RGC degeneration through the activation of the Trk B pathway in RGC-5 cell lines.RGC-5 cell lines were pre-treated with imipramine 30 minutes before exposure to H_2O_2.Western blot assay showed that in H_2O_2-damaged RGC-5 cells,imipramine activated Trk B pathways through extracellular signal-regulated protein kinase/Trk B phosphorylation.TUNEL staining assay also demonstrated that imipramine ameliorated H_2O_2-induced apoptosis in RGC-5 cells.Finally,Trk B-Ig G intervention was able to reverse the protective effect of imipramine on H_2O_2-induced RGC-5 apoptosis.Imipramine therefore protects RGCs from oxidative stress-induced apoptosis through the Trk B signaling pathway.展开更多
AIM: To observe the effect of Lycium barbarum polysaccharide (LBP) on rat retinal ganglion cells (RGCs) in vitro. METHODS: Retinal cells of neonatal Sprague-Dawley rats were collected 1 to 3 days after birth, and co-c...AIM: To observe the effect of Lycium barbarum polysaccharide (LBP) on rat retinal ganglion cells (RGCs) in vitro. METHODS: Retinal cells of neonatal Sprague-Dawley rats were collected 1 to 3 days after birth, and co-cultured with different concentrations of LBP for 24 hours. Absorbance values (OD) were recorded using MTT assay for calculating survival rates. RESULTS: All the test groups had protective effects on RGCs. The group with 10mg/mL concentration of LBP had the most significantly difference of OD value compared with that in control group (P <0.01). CONCLUSION: LBP can increase the survival rate and promote the growth of mixed cultured rat RGCs.展开更多
Our previous studies revealed that etomidate, a non-barbiturate intravenous anesthetic agent, has protective effects on retinal ganglion cells within 7 days after optic nerve transection. Whether this process is relat...Our previous studies revealed that etomidate, a non-barbiturate intravenous anesthetic agent, has protective effects on retinal ganglion cells within 7 days after optic nerve transection. Whether this process is related to anti-oxidative stress is not clear. To reveal its mechanism, we established the optic nerve transection injury model by transecting 1 mm behind the left eyeball of adult male Sprague-Dawley rats. The rats received an intraperitoneal injection of etomidate(4 mg/kg) once per day for 7 days. The results showed that etomidate significantly enhanced the number of retinal ganglion cells retrogradely labeled with Fluorogold at 7 days after optic nerve transection. Etomidate also significantly reduced the levels of nitric oxide and malonaldehyde in the retina and increased the level of glutathione at 12 hours after optic nerve transection. Thus, etomidate can protect retinal ganglion cells after optic nerve transection in adult rats by activating an anti-oxidative stress response. The study was approved by the Animal Ethics Committee at Air Force Medical University, China(approval No. 20180305) on March 5, 2018.展开更多
Glaucoma is a common optic neuropathy that is characterized by the progressive degeneration of axons and the loss of retinal ganglion cells(RGCs). Glaucoma is one of the leading causes of irreversible blindness worldw...Glaucoma is a common optic neuropathy that is characterized by the progressive degeneration of axons and the loss of retinal ganglion cells(RGCs). Glaucoma is one of the leading causes of irreversible blindness worldwide. Current glaucoma treatments only slow the progression of RGCs loss. Induced pluripotent stem cells(iPSCs) are capable of differentiating into all three germ layer cell lineages. iPSCs can be patient-specific,making iPSC-derived RGCs a promising candidate for cell replacement. In this review, we focus on discussing the detailed approaches used to differentiate iPSCs into RGCs.展开更多
AIM:To investigate the neuroprotective effect of gastrodin on retinal ganglion cells(RGCs) in an acute ocular hypertension(AOH) rat model and to identify its possible mechanism.METHODS:AOH rat model was performed in a...AIM:To investigate the neuroprotective effect of gastrodin on retinal ganglion cells(RGCs) in an acute ocular hypertension(AOH) rat model and to identify its possible mechanism.METHODS:AOH rat model was performed in a randomly selected eye by anterior chamber perfusion and either received an intraperitoneal injection with various concentrations of gastrodin or normal saline.After 2 wk,the rats were sacrificed.Fluoro Gold was used to label survival RGCs.Immunostaining with anti-Iba1 in the retinal flat mounts to calculate the microglia density in the ganglion cell layer(GCL).Changes in microglial cytokines,tumour necrosis factor-alpha(TNF-α) and inducible NO synthase(i NOS) were examined with Western blot and reverse transcriptionquantitative polymerase chain reaction.Expression levels of total and phosphorylated p38 mitogen activated protein kinase(MAPK) were determined by Western blot.RESULTS:Results showed that AOH induced significant loss of RGCs and severe microglia activation in the GCL.Besides,AOH increased the phosphorylation of p38 MAPK and promoted the release of microglial cytokines in the retinas.Intraperitoneal injection with dose-dependent gastrodin significantly reduced the loss of RGCs and inhibited retinal microglia activation,accompanied with the decreased expression levels of microglial cytokines and p38 MAPK phosphorylation.CONCLUSION:Gastrodin exerts a neuroprotective effect on RGCs in an acute glaucoma animal model viainhibiting microglia activation and microglial-mediated neuroinflammation.The finding demonstrates the potential application of gastrodin in the neuroprotective therapy of acute glaucoma and other retinal neurodegenerative diseases characterized by microglia activation and RGCs death.展开更多
AIM: To investigate the anti-apoptotic effect of transforming growth factor beta-1 (TGF-β1) on chronic ocular hypertension. METHODS: The expression of TGF-β1 in retinal ganglion cells (RCGs) was measured using the i...AIM: To investigate the anti-apoptotic effect of transforming growth factor beta-1 (TGF-β1) on chronic ocular hypertension. METHODS: The expression of TGF-β1 in retinal ganglion cells (RCGs) was measured using the immunohistochemiscal S-P method and real-time PCR in the normally control group, the ocular hypertension group (experimental group A), the ocular hypertension plus antibody intervention group (experimental group B) and the ocular hypertension plus antigen intervention group (experimental group C) at 1, 2, 3 and 4 weeks postoperatively. The count of apoptotic RCGs was measured using the TUNEL method. RESULTS: The expression of TGF-β1 was significantly higher in experimental group C than that in other three groups (P<0.05). The expression was the lowest in experimental group B (4.17%). A statistically significant difference was noted between the four groups (P <0.01). The count of apoptotic RCGs was statistically significantly lower in experimental group C than that in the experimental groups A and B (P <0.01). A statistically significant difference was noted in the count of apoptotic RCGs between these three experimental groups (P <0.01). CONCLUSION: TGF-β1 can inhibit the apoptosis of RCGs in rats with chronic ocular hypertension.展开更多
AIM: To investigate the effect of interleukin-8(IL-8) on neural retinal ganglion cells(RGCs) and whether it can be alleviated by G31P. METHODS: RGC-5 cells were exposed to IL-8 with or without its specific receptor an...AIM: To investigate the effect of interleukin-8(IL-8) on neural retinal ganglion cells(RGCs) and whether it can be alleviated by G31P. METHODS: RGC-5 cells were exposed to IL-8 with or without its specific receptor antagonist G31P for 24h, and the cell viability was assessed by Cell Counting Kit 8(CCK-8). Apoptosis was measured by examining nuclear morphology and quantifying with flow cytometry. Reverse transcription quantitative real-time polymerase chain reaction(RT-qP CR) and Western blot were used to investigate the expression of apoptosis-related genes. RESULTS: CCK-8 assay showed that IL-8 significantly inhibits the viability of RGC-5 cells in a dose-dependent manner. Cell apoptosis assays exhibited higher apoptotic rate in IL-8 treatment group compared to control group. We further found that IL-8 could promote Bax and caspase-3 expressions, but decrease the level of Bcl-2 in the aspect of m RNA and protein. However, pre-treatment with G31P partly attenuated these effects in RGC-5 cells(P<0.05).CONCLUSION: These results indicate that anti-proliferation effects of IL-8 through induction of cell apoptosis regulated by Bcl-2, Bax and caspase-3 expressions, can be ameliorated by G31P.展开更多
AIM: To investigate the effect of DSX, an active component extracted from Erigeron breviscapus, on the voltage-gated outward K+channel currents in rat retinal ganglion cells(RGCs) by using electrophysiological method,...AIM: To investigate the effect of DSX, an active component extracted from Erigeron breviscapus, on the voltage-gated outward K+channel currents in rat retinal ganglion cells(RGCs) by using electrophysiological method, and to explore the possible mechanisms of DSX on optic nerve protection.· METHODS: Outward K + currents were recorded by using whole-cell patch-clamp techniques on acutely isolated rat RGCs. Outward K+currents were induced by a series of depolarizing voltage pulses from a holding potential of-70 m V to +20 m V in an increment of 10 m V.·RESULTS: Extracellular application of DSX voltage-dependently suppressed both the steady-state and peak current amplitudes of outward K+currents in rat RGCs.Furthermore, DSX reversibly and dose-dependently inhibited the amplitudes of outward K+currents of the cells. At +20 m V membrane potential DSX at the concentrations of 0.02 g/L and 0.05 g/L showed no significant effects on the currents. In contrast, DSX at higher concentrations(0.1 g/L, 0.2 g/L and 0.5 g/L)significantly suppressed the current amplitudes.· CONCLUSION: These results suggest that DSX reversibly and dose-dependently suppress outward K+channel currents in rat RGCs, which may be one of the possible mechanisms underlying Erigeron breviscapus prevents vision loss and RGC damage caused by glaucoma.展开更多
AIM: To characterize the pattern of intraocular pressure(IOP) change and the deficit of retinal ganglion cells(RGCs) in DBA2 J, which is most well-characterized chronic glaucoma mouse model and wild type(WT)C57bl/6 mi...AIM: To characterize the pattern of intraocular pressure(IOP) change and the deficit of retinal ganglion cells(RGCs) in DBA2 J, which is most well-characterized chronic glaucoma mouse model and wild type(WT)C57bl/6 mice, and to study the relationship between IOP change and RGCs deficit.·METHODS:IOPwasmonitoredwitharebound tonometer in WT C57bl/6 and DBA2 J mice from 3 to 15-month-old.Retinal function was evaluated by dark-adapted electroretinogram( ERG) in DBA2 J and WT mice of15-month-old. A dye(Neurobiotin) was applied to optic nerve stump to retrograde label RGCs. TO-PRO-3visualized all nuclei of cells in the RGC layer.·RESULTS: The IOP in WT mice was 9.03±0.6 mm Hg on average and did not increase significantly as aging.The IOP in DBA2 J mice, arranging from 7.2 to 28 mm Hg,was increasing significantly as aging, and it was normal at 3-month-old compared with WT mice, slightly increased from 7- month- old and increased in 50 % animals at11-month-old and in 38% animals at 15-month-old. The RGCs density in DBA2 J mice started reducing by7-month-old, continuously decreased until reached about 20% of RGC in WT retina by 15-month-old. RGC density was not linearly correlated with IOP in 15-monthold DBA2 J mice. The amplitude of positive scotopic threshold response, and negative scotopic threshold response of ERG were significantly reduced in DBA2 J mice of 15-month-old than that in age-paired WT mice.·CONCLUSION: The present study found that DBA2 J mice display pathological and functional deficits of the retina that was not linearly correlated with IOP.展开更多
AIM: To investigate the relationships between the changes of heat shock protein 27 antibody(anti-HSP27) in serum/cerebrospinal fluid(CSF), intraocular pressure(IOP), retinal ganglion cell(RGC) apoptosis in a rat glauc...AIM: To investigate the relationships between the changes of heat shock protein 27 antibody(anti-HSP27) in serum/cerebrospinal fluid(CSF), intraocular pressure(IOP), retinal ganglion cell(RGC) apoptosis in a rat glaucoma model and disclose the underlying pathogenesis of glaucoma.METHODS: A total of 115 Wistar rats were randomly divided into 4 groups. Group 1 was the ocular hypertension group by condensing 3 episcleral & limbal veins or episcleral area of right eye(HP group, n=25) and sham operation group with conjunctiva incision without coagulation(n=25). Group 2: HSP27 or dose-matched PBS was injected into the vitreous(V-HSP27 group, n=15;V-PBS group, n=15). Group 3: HSP27 and complete Freund's adjuvant or dosematched PBS was injected subcutaneously into the hind limb accompanied intraperitoneal injection of pertussis toxin [sensitized group(I-HSP27 group), n=15;I-PBS group, n=15)]. Group 4 was normal group without any treatment(n=5). IOPs of the rats were measured before, day 3, weeks 1, 2, 4, 6, and 8 after treatment. Paraffin-embedded sections were prepared for HE staining and RGCs apoptosis were detected by TUNEL. Anti-HSP27 level in serum and CSF were examined by ELISA. RESULTS: IOPs were elevated significantly in HP and V-HSP27, V-PBS groups(P<0.01) and positively related to anti-HSP27 levels in serum and CSFs. Anti-HSP27 levels in serum and CSF were elevated significantly in I-HSP27group compared to other groups(P<0.05). However, the IOPs did not show any relationship with the high-level antiHSP27 in serum and CSFs. RGC apoptosis were all elevated significantly in the HP, V-HSP27, V-PBS and I-HSP27 groups and also positively relative with anti-HSP27 level in serum and CSFs except that high-level of anti-HSP27 in the serum of I-HSP group.CONCLUSION: The increases of anti-HSP27 levels in serum and CSFs both promote IOP escalation and the increase of RGC apoptosis in retina when anti-HSP27 is at low level. The case of high-level anti-HSP27 is opposite and shows protective function in preventing IOP increase and RGC apoptosis.展开更多
基金Supported by the Natural Science Foundation of Guangdong Province(No.2018A0303130293,No.2023A1515012470).
文摘AIM:To investigate the effects of Sonic hedgehog(Shh)gene-modified bone marrow mesenchymal stem cells(MSCs)on graft-induced retinal gliosis and retinal ganglion cells(RGCs)survival in diabetic mice.METHODS:Bone marrow-derived MSCs were genetically modified with the Shh gene to generate a stably transfected cell line of Shh-modified MSCs(MSC-Shh).Intravitreal injections of MSC-Shh and green fluorescent protein-modified MSCs(MSC-Gfp;control)were administered in diabetic mice.After 4wk,the effects of MSC-Shh on retinal gliosis were evaluated using fundus photography,and markers of gliosis were examined by immunofluorescence and Western blotting.The neurotrophic factors expression and RGCs survival in the host retina were evaluated using Western blotting and immunofluorescence.The mechanisms underlying the effects of MSC-Shh was investigated.RESULTS:A significant reduction of proliferative vitreoretinopathy(PVR)was observed after intravitreal injection of MSC-Shh compared to MSC-Gfp.Significant downregulation of glial fibrillary acidic protein(GFAP)was demonstrated in the host retina after MSC-Shh administration compared to MSC-Gfp.The extracellular signal-regulated kinase 1/2(ERK1/2),protein kinase B(AKT)and phosphatidylin-ositol-3-kinase(PI3K)pathways were significantly downregulated after MSC-Shh administration compared to MSC-Gfp.Brain-derived neurotrophic factor(BDNF)and ciliary neurotrophic factor(CNTF)levels were significantly increased in the host retina,and RGCs loss was significantly prevented after MSC-Shh administration.CONCLUSION:MSC-Shh administration reduces graft-induced reactive gliosis following intravitreal injection in diabetic mice.The ERK1/2,AKT and PI3K pathways are involved in this process.MSC-Shh also increases the levels of neurotrophic factors in the host retina and promoted RGCs survival in diabetic mice.
基金supported by NIH Core Grants P30-EY008098the Eye and Ear Foundation of Pittsburghunrestricted grants from Research to Prevent Blindness,New York,NY,USA(to KCC)。
文摘Glaucoma,characterized by a degenerative loss of retinal ganglion cells,is the second leading cause of blindness worldwide.There is currently no cure for vision loss in glaucoma because retinal ganglion cells do not regenerate and are not replaced after injury.Human stem cell-derived retinal ganglion cell transplant is a potential therapeutic strategy for retinal ganglion cell degenerative diseases.In this review,we first discuss a 2D protocol for retinal ganglion cell differentiation from human stem cell culture,including a rapid protocol that can generate retinal ganglion cells in less than two weeks and focus on their transplantation outcomes.Next,we discuss using 3D retinal organoids for retinal ganglion cell transplantation,comparing cell suspensions and clusters.This review provides insight into current knowledge on human stem cell-derived retinal ganglion cell differentiation and transplantation,with an impact on the field of regenerative medicine and especially retinal ganglion cell degenerative diseases such as glaucoma and other optic neuropathies.
基金supported by grants from Project of Administration of Traditional Chinese Medicine of Guangdong Province of China,No.20161071(to LL)Medical Scientific Research Foundation of Guangdong Province of China,No.A2019098(to LL)
文摘The accumulation of excessive reactive oxygen species can exacerbate any injury of retinal tissue because free radicals can trigger lipid peroxidation,protein damage and DNA fragmentation.Increased oxidative stress is associated with the common pathological process of many eye diseases,such as glaucoma,diabetic retinopathy and ischemic optic neuropathy.Many studies have demonstrated that Lycium barbarum polysaccharides(LBP)protects against oxidative injury in numerous cells and tissues.For the model of hypoxia we used cultured retinal ganglion cells and induced hypoxia by incubating with 200μM cobalt chloride(CoCl2)for 24 hours.To investigate the protective effect of LBP and its mechanism of action against oxidative stress injury,the retinal tissue was pretreated with 0.5 mg/mL LBP for 24 hours.The results of flow cytometric analysis showed LBP could effectively reduce the CoCl2-induced retinal ganglion cell apoptosis,inhibited the generation of reactive oxygen species and the reduction of mitochondrial membrane potential.These findings suggested that LBP could protect retinal ganglion cells from CoCl2-induced apoptosis by reducing mitochondrial membrane potential and reactive oxygen species.
基金Supported by Ph.D.Programs Foundation of Ministry of Education of China(No.20130141120052)
文摘AIM: To explore the effect of ciliary neurotrophic factor(CNTF) on retinal ganglion cell(RGC)-5 induced by hydrogen peroxide(H_2O_2). METHODS: After cell adherence, RGC-5 culture medium was changed to contain different concentrations of H_2O_2 from50 to 150 μmol/L at four time points(0.5, 1, 1.5 and 2 h) to select the concentration and time point for H_2O_2 induced model. Two different ways of interventions for injured RGC-5 cells respectively were CNTF as an addition in the culture medium or recombinant lentiviral plasmid carrying CNTF gene transfecting bone mesenchymal stem cells(BMSCs) for co-culture with RGC-5. RESULTS: Compared to the control group, H_2O_2 led to RGC-5 death closely associated with concentrations and action time of H_2O_2 and we chose 125 μmol/L and 2 h to establish the H_2O_2-induced model. While CNTF inhibited the loss of RGC-5 cells obviously with a dose-dependent survival rate. Nevertheless two administration routes had different survival rate yet higher rate in recombinant lentiviral plasmid group but there were no statistically significant differences. CONCLUSION: Both the two administration routes of CNTF have effects on RGC-5 cells induced by H_2O_2. If their own advantages were combined, there may be a better administration route.
文摘AIM: To explore if ischemic preconditioning(IPC) can enhance the survival of retinal ganglion cells(RGCs) after optic nerve axotomy. METHODS: Twenty-four hours prior to retinal ischemia 60 min or axotomy, IPC was applied for ten minutes in groups of(n=72) animals. The survival of RGCs, the cellular expression of heat shock protein 27(HSP27) and heat shock protein 70(HSP70) and the numbers of retinal microglia in the different groups were quantified at 7 and 14 d post-injury. The cellular expression of HSP27 and HSP70 and changes in the numbers of retinal microglia were quantified to detect the possible mechanism of the protection of the IPC. RESULTS: Ten minutes of IPC promoted RGC survival in both the optic nerve injury(IPC-ONT) and the retinal ischemia 60min(IPC-IR60) groups, examined at 7d and 14 d post-injury. Microglial proliferation showed little correlation with the extent of benefit effects of IPC on the rescue of RGCs. The number of HSP27-positive RGCs was significantly higher in the IPC-ONT group than in the sham IPC-ONT group, although the percentage of HSP27-positive RGCs did not significantly differ between groups. For the IPC-IR60 group, neither the number nor the percentage of the HSP27-positive RGCs differed significantly between the IPC and the sham-operated groups. The number of HSP70-positive RGCs was significantly higher for both the IPC-ONT and the IPC-IR60 experimental groups, but the percentages did not differ. CONCLUSION: The induction of IPC enhances the survival of RGCs against both axotomy and retinal ischemia.
文摘BACKGROUND:Previous studies have shown that nerve regeneration factor (NRF) provides neuroprotective effects. However,the neuroprotective effects on retinal ganglion cells in an animal model of glaucoma remain uncertain. OBJECTIVE:To determine the neuroprotective effects of NRF on retinal ganglion cells in a rabbit model of acute hyper-intraocular pressure and to compare the effects on brain-derived neurotrophic factor (BDNF). DESIGN,TIME AND SETTING:A randomized,controlled,animal experiment was performed at Jiangsu Provincial Key Laboratory of Neural Regeneration from September 2006 to August 2007. MATERIALS:Sterone,a major component of NRF,was provided by the Key Laboratory of Neural Regeneration,Nantong University in China; BDNF was provided by BioDesign Inc.,USA. METHODS:A total of 24 healthy rabbits were randomly assigned to NRF,BDNF,and phosphate buffered saline groups,with 8 rabbits per group. The left eyes were considered normal controls,and acute hyper-intraocular pressure was induced in the right eyes via anterior chamber perfusion. The right camera vitrea bulbi was injected with 4.5 μg NRF,3.75 μg BDNF,or 5 μL 0.1 mol/L phosphate buffered saline,respectively. MAIN OUTCOME MEASURES:Retinal ganglion cells were reverse-labeled using horseradish peroxidase to quantify cell density at 2,4,and 6 mm from the optic disc edge. RESULTS:NRF increased the number of surviving retinal ganglion cells at the optic disc edge (P < 0.01 or P < 0.05). The density of surviving retinal ganglion cells decreased with increasing distance from the optic disc. The number of retinal ganglion cells in the BDNF group was similar to the NRF group (P > 0.05). At 2,4,and 6 mm away from the optic disc edge,there was no significant difference in retinal ganglion cell density between NRF and BDNF groups (P > 0.05). CONCLUSION:NRF provided protection to retinal ganglion cells in a rabbit model of acute hyper-intraocular pressure,i.e.,NRF enhanced the survival rate of retinal ganglion cells. The neuroprotective effect was similar to BDNF.
基金supported by the NIH Center Core Grant,No.P30EY014801(to Bascom Palmer Eye Institute)and a Research to Prevent Blindness Unrestricted Grant(to Bascom Palmer Eye Institute)the Walter G.Ross Foundation(to RKL).
文摘The mammalian retina displays incomplete intrinsic regenerative capacities;therefore,retina degeneration is a major cause of irreversible blindness such as glaucoma,agerelated macular degeneration and diabetic retinopathy.These diseases lead to the loss of retinal cells and serious vision loss in the late stage.Stem cell transplantation is a great promising novel treatment for these incurable retinal degenerative diseases and represents an exciting area of regenerative neurotherapy.Several suitable stem cell sources for transplantation including human embryonic stem cells,induced pluripotent stem cells and adult stem cells have been identified as promising target populations.However,the retina is an elegant neuronal complex composed of various types of cells with different functions.The replacement of these different types of cells by transplantation should be addressed separately.So far,retinal pigment epithelium transplantation has achieved the most advanced stage of clinical trials,while transplantation of retinal neurons such as retinal ganglion cells and photoreceptors has been mostly studied in pre-clinical animal models.In this review,we opine on the key problems that need to be addressed before stem cells transplantation,especially for replacing injured retinal ganglion cells,may be used practically for treatment.A key problem we have called the Switchboard Dilemma is a major block to have functional retinal ganglion cell replacement.We use the public switchboard telephone network as an example to illustrate different difficulties for replacing damaged components in the retina that allow for visual signaling.Retinal ganglion cell transplantation is confronted by significant hurdles,because retinal ganglion cells receive signals from different interneurons,integrate and send signals to the correct targets of the visual system,which functions similar to the switchboard in a telephone network-therefore the Switchboard Dilemma.
基金Supported by the National Natural Science Foundation of China(No.81970806)Medical Scientific Research Foundation of Guangdong Province of China(No.A2019098)。
文摘AIM:To observe the protective effect of human umbilical cord mesenchymal stem cells(huc MSCs)on retinal ganglion cel s(RGCs)injury in mice with acute ocular hypertension(AOH).METHODS:Fifty-six adult male C57 BL/6 mice were randomly divided into four groups:normal group,AOH group,huc MSCs group,normal saline(NS)group.Left eye of mice was induced by 90 mm Hg intraocular pressure for 1 h to establish AOH model.huc MSCs 1×105/μL,1μL or NS 1μL was injected into the vitreous body the next day.CMDil fluorescent dye was used to label the 3 rd generation of huc MSCs,for tracing the cells in the vitreous cavity of mice.Seven days after the model established,hematoxylin-eosin(HE)staining was used to observe the thickness of the inner retina layer in four groups.Numbers and loss rate of RGCs were evaluated by counting Brn-3 a positive cells stained by immunofluorescencein.RESULTS:On the 7 th day after AOH established,labeled huc MSCs were found in the vitreous cavity.HE staining showed that the thickness of retinal inner layer in AOH group was significantly lower than that in normal group and huc MSCs group(P<0.05),same as that in NS group(P>0.05).Compared with AOH group,the RGCs in normal group was significantly higher;RGCs number increased in huc MSCs group and the loss rate was lower(P<0.05).Injection of NS had no protective effect on RGCs.CONCLUSION:In AOH mouse model,vitreous injection of hucMSCs have shown a protection for RGCs.
基金Supported by National Natural Science Foundation of China(No.81400400)
文摘AIM:To investigate the role of Brn-3b in differentiation process of stem cells derived from retinal Miiller cells into the ganglion cell.METHODS:The passage culture method of Miiller cells from retina of newborn Sprague Dawley rats was carried out by repeated incomplete pancreatic enzyme digestion method.The cells were detected by fluorescenceactivated cell sorter(FACS),immunohistochemistry technology and reverse transcription-polymerase chain reaction(RT-PCR) to determine the purity.The third passage of cells was induced in the serum-free dedifferentiation medium.The expression of the specific markers Ki-67 and nestin of retinal stem cells was measured by RT-PCR and Western blot.The cell proliferation of retinal stem cells was detected by 5-Ethynyl-2'-deoxyuridine(Edu) staining.The cells were randomly divided into 5 groups as follows:group A:Brn-3bsiRNA group;group B:Brn-3b control siRNA group;group C:pGC-Brn-3b-green fluorescent protein(GFP) group;group D:pGC-GFP group;group E:control group(without any handling).The purified Muller cells were cultured for 3-7d,then,the percentage of ganglion cells was counted by immunofluorescence staining.RESULTS:FACS demonstrated the purity of retinal Muller cells was more 97.44%.A few spherical cell spheres appeared.Immunofluorescence staining showed that stem cells within the spheres were positive for retinal stem cell-specific markers nestin(red fluorescence,92.94%±6.48%) and Ki-67(green fluorescence,85.96%±6.04%).Meanwhile,RT-PCR analysis showed cell spheres in the culture to have expressed a battery of transcripts characteristic of stem cells such as nestin and Ki-67,which were absent in the Muller cells.Western blot analysis further confirmed the expression of nestin and Ki-67 in the cell spheres but not in the Muller cells.Edu staining showed most of the nuclei within the cell spheres were stained red(82.80%±6.65%),suggesting the new cell spheres had the capacity for effective proliferation.The statistics result showed the difference between Brn-3bsiRNA group and Brn-3b control siRNA group or the control group was significant(F=15,P<0.05),while the difference between Brn-3b control siRNA group or the control group was not statistically significant(P>0.05).CONCLUSION:The repeated incomplete pancreatic enzyme digestion method is an efficient and practical method to purify retinal M(u|¨)ller cells.Retinal stem cells were successfully cloned in the dedifferentiational medium.Retinal M(u|¨)ller cells are accessible sources of retinal stem cells.Brn-3b is an important regulatory gene in stem cells differentiated into retinal ganglion cell.
文摘Human central nerve system(CNS)is an extremely complex and delicate structure.While regeneration is possible in some reptiles and fish CNS,the regeneration capacity seems completely lost in adult mammals.Therefore,the classic concept is that once neurons in mammal
文摘Retinal ganglion cell(RGC) degeneration is irreversible in glaucoma and tyrosine kinase receptor B(Trk B)-associated signaling pathways have been implicated in the process.In this study,we attempted to examine whether imipramine,a tricyclic antidepressant,may protect hydrogen peroxide(H_2O_2)-induced RGC degeneration through the activation of the Trk B pathway in RGC-5 cell lines.RGC-5 cell lines were pre-treated with imipramine 30 minutes before exposure to H_2O_2.Western blot assay showed that in H_2O_2-damaged RGC-5 cells,imipramine activated Trk B pathways through extracellular signal-regulated protein kinase/Trk B phosphorylation.TUNEL staining assay also demonstrated that imipramine ameliorated H_2O_2-induced apoptosis in RGC-5 cells.Finally,Trk B-Ig G intervention was able to reverse the protective effect of imipramine on H_2O_2-induced RGC-5 apoptosis.Imipramine therefore protects RGCs from oxidative stress-induced apoptosis through the Trk B signaling pathway.
基金Key Projects--Major New Drugs of National Science and Technology Ministry,China (2009ZX09103-369)Key Research Project of National Education MinistryKey Project of Sichuan Provincial Education Department, China (08ZA118)
文摘AIM: To observe the effect of Lycium barbarum polysaccharide (LBP) on rat retinal ganglion cells (RGCs) in vitro. METHODS: Retinal cells of neonatal Sprague-Dawley rats were collected 1 to 3 days after birth, and co-cultured with different concentrations of LBP for 24 hours. Absorbance values (OD) were recorded using MTT assay for calculating survival rates. RESULTS: All the test groups had protective effects on RGCs. The group with 10mg/mL concentration of LBP had the most significantly difference of OD value compared with that in control group (P <0.01). CONCLUSION: LBP can increase the survival rate and promote the growth of mixed cultured rat RGCs.
基金supported by the National Natural Science Foundation of China,No.81670846(to MMW)and 81470631(to SWY)the Natural Science Foundation of Shaanxi Province of China,No.2016SF-171(to MMW)the National Basic Research Program of China,No.2014CB542202(to SWY)
文摘Our previous studies revealed that etomidate, a non-barbiturate intravenous anesthetic agent, has protective effects on retinal ganglion cells within 7 days after optic nerve transection. Whether this process is related to anti-oxidative stress is not clear. To reveal its mechanism, we established the optic nerve transection injury model by transecting 1 mm behind the left eyeball of adult male Sprague-Dawley rats. The rats received an intraperitoneal injection of etomidate(4 mg/kg) once per day for 7 days. The results showed that etomidate significantly enhanced the number of retinal ganglion cells retrogradely labeled with Fluorogold at 7 days after optic nerve transection. Etomidate also significantly reduced the levels of nitric oxide and malonaldehyde in the retina and increased the level of glutathione at 12 hours after optic nerve transection. Thus, etomidate can protect retinal ganglion cells after optic nerve transection in adult rats by activating an anti-oxidative stress response. The study was approved by the Animal Ethics Committee at Air Force Medical University, China(approval No. 20180305) on March 5, 2018.
基金Supported by "555 Talent Plan" Grant from the Changsha National High-Tech Industrial Development Zoom
文摘Glaucoma is a common optic neuropathy that is characterized by the progressive degeneration of axons and the loss of retinal ganglion cells(RGCs). Glaucoma is one of the leading causes of irreversible blindness worldwide. Current glaucoma treatments only slow the progression of RGCs loss. Induced pluripotent stem cells(iPSCs) are capable of differentiating into all three germ layer cell lineages. iPSCs can be patient-specific,making iPSC-derived RGCs a promising candidate for cell replacement. In this review, we focus on discussing the detailed approaches used to differentiate iPSCs into RGCs.
基金Supported by the Natural Science Foundation of Shandong Province,China(No.ZR2017BH049)
文摘AIM:To investigate the neuroprotective effect of gastrodin on retinal ganglion cells(RGCs) in an acute ocular hypertension(AOH) rat model and to identify its possible mechanism.METHODS:AOH rat model was performed in a randomly selected eye by anterior chamber perfusion and either received an intraperitoneal injection with various concentrations of gastrodin or normal saline.After 2 wk,the rats were sacrificed.Fluoro Gold was used to label survival RGCs.Immunostaining with anti-Iba1 in the retinal flat mounts to calculate the microglia density in the ganglion cell layer(GCL).Changes in microglial cytokines,tumour necrosis factor-alpha(TNF-α) and inducible NO synthase(i NOS) were examined with Western blot and reverse transcriptionquantitative polymerase chain reaction.Expression levels of total and phosphorylated p38 mitogen activated protein kinase(MAPK) were determined by Western blot.RESULTS:Results showed that AOH induced significant loss of RGCs and severe microglia activation in the GCL.Besides,AOH increased the phosphorylation of p38 MAPK and promoted the release of microglial cytokines in the retinas.Intraperitoneal injection with dose-dependent gastrodin significantly reduced the loss of RGCs and inhibited retinal microglia activation,accompanied with the decreased expression levels of microglial cytokines and p38 MAPK phosphorylation.CONCLUSION:Gastrodin exerts a neuroprotective effect on RGCs in an acute glaucoma animal model viainhibiting microglia activation and microglial-mediated neuroinflammation.The finding demonstrates the potential application of gastrodin in the neuroprotective therapy of acute glaucoma and other retinal neurodegenerative diseases characterized by microglia activation and RGCs death.
文摘AIM: To investigate the anti-apoptotic effect of transforming growth factor beta-1 (TGF-β1) on chronic ocular hypertension. METHODS: The expression of TGF-β1 in retinal ganglion cells (RCGs) was measured using the immunohistochemiscal S-P method and real-time PCR in the normally control group, the ocular hypertension group (experimental group A), the ocular hypertension plus antibody intervention group (experimental group B) and the ocular hypertension plus antigen intervention group (experimental group C) at 1, 2, 3 and 4 weeks postoperatively. The count of apoptotic RCGs was measured using the TUNEL method. RESULTS: The expression of TGF-β1 was significantly higher in experimental group C than that in other three groups (P<0.05). The expression was the lowest in experimental group B (4.17%). A statistically significant difference was noted between the four groups (P <0.01). The count of apoptotic RCGs was statistically significantly lower in experimental group C than that in the experimental groups A and B (P <0.01). A statistically significant difference was noted in the count of apoptotic RCGs between these three experimental groups (P <0.01). CONCLUSION: TGF-β1 can inhibit the apoptosis of RCGs in rats with chronic ocular hypertension.
文摘AIM: To investigate the effect of interleukin-8(IL-8) on neural retinal ganglion cells(RGCs) and whether it can be alleviated by G31P. METHODS: RGC-5 cells were exposed to IL-8 with or without its specific receptor antagonist G31P for 24h, and the cell viability was assessed by Cell Counting Kit 8(CCK-8). Apoptosis was measured by examining nuclear morphology and quantifying with flow cytometry. Reverse transcription quantitative real-time polymerase chain reaction(RT-qP CR) and Western blot were used to investigate the expression of apoptosis-related genes. RESULTS: CCK-8 assay showed that IL-8 significantly inhibits the viability of RGC-5 cells in a dose-dependent manner. Cell apoptosis assays exhibited higher apoptotic rate in IL-8 treatment group compared to control group. We further found that IL-8 could promote Bax and caspase-3 expressions, but decrease the level of Bcl-2 in the aspect of m RNA and protein. However, pre-treatment with G31P partly attenuated these effects in RGC-5 cells(P<0.05).CONCLUSION: These results indicate that anti-proliferation effects of IL-8 through induction of cell apoptosis regulated by Bcl-2, Bax and caspase-3 expressions, can be ameliorated by G31P.
基金Supported by National Major Science-Technology Project of Science and Technology Ministry-Major New Medicine Innovation (No.2009ZX09103-369)Key Project of Chinese Ministry of Education2014 Sichuan Province Academic and Technology Leaders Training Funds
文摘AIM: To investigate the effect of DSX, an active component extracted from Erigeron breviscapus, on the voltage-gated outward K+channel currents in rat retinal ganglion cells(RGCs) by using electrophysiological method, and to explore the possible mechanisms of DSX on optic nerve protection.· METHODS: Outward K + currents were recorded by using whole-cell patch-clamp techniques on acutely isolated rat RGCs. Outward K+currents were induced by a series of depolarizing voltage pulses from a holding potential of-70 m V to +20 m V in an increment of 10 m V.·RESULTS: Extracellular application of DSX voltage-dependently suppressed both the steady-state and peak current amplitudes of outward K+currents in rat RGCs.Furthermore, DSX reversibly and dose-dependently inhibited the amplitudes of outward K+currents of the cells. At +20 m V membrane potential DSX at the concentrations of 0.02 g/L and 0.05 g/L showed no significant effects on the currents. In contrast, DSX at higher concentrations(0.1 g/L, 0.2 g/L and 0.5 g/L)significantly suppressed the current amplitudes.· CONCLUSION: These results suggest that DSX reversibly and dose-dependently suppress outward K+channel currents in rat RGCs, which may be one of the possible mechanisms underlying Erigeron breviscapus prevents vision loss and RGC damage caused by glaucoma.
基金Supported by International Retinal Research Foundation
文摘AIM: To characterize the pattern of intraocular pressure(IOP) change and the deficit of retinal ganglion cells(RGCs) in DBA2 J, which is most well-characterized chronic glaucoma mouse model and wild type(WT)C57bl/6 mice, and to study the relationship between IOP change and RGCs deficit.·METHODS:IOPwasmonitoredwitharebound tonometer in WT C57bl/6 and DBA2 J mice from 3 to 15-month-old.Retinal function was evaluated by dark-adapted electroretinogram( ERG) in DBA2 J and WT mice of15-month-old. A dye(Neurobiotin) was applied to optic nerve stump to retrograde label RGCs. TO-PRO-3visualized all nuclei of cells in the RGC layer.·RESULTS: The IOP in WT mice was 9.03±0.6 mm Hg on average and did not increase significantly as aging.The IOP in DBA2 J mice, arranging from 7.2 to 28 mm Hg,was increasing significantly as aging, and it was normal at 3-month-old compared with WT mice, slightly increased from 7- month- old and increased in 50 % animals at11-month-old and in 38% animals at 15-month-old. The RGCs density in DBA2 J mice started reducing by7-month-old, continuously decreased until reached about 20% of RGC in WT retina by 15-month-old. RGC density was not linearly correlated with IOP in 15-monthold DBA2 J mice. The amplitude of positive scotopic threshold response, and negative scotopic threshold response of ERG were significantly reduced in DBA2 J mice of 15-month-old than that in age-paired WT mice.·CONCLUSION: The present study found that DBA2 J mice display pathological and functional deficits of the retina that was not linearly correlated with IOP.
基金Supported by National Natural Science Foundation of China(No.81060077)Key Research and Development Program in Yunnan Province(International Science and Technology Cooperation,No.2017IB001)Science and Technology Planning Project of Guangzhou(No.201604020105)。
文摘AIM: To investigate the relationships between the changes of heat shock protein 27 antibody(anti-HSP27) in serum/cerebrospinal fluid(CSF), intraocular pressure(IOP), retinal ganglion cell(RGC) apoptosis in a rat glaucoma model and disclose the underlying pathogenesis of glaucoma.METHODS: A total of 115 Wistar rats were randomly divided into 4 groups. Group 1 was the ocular hypertension group by condensing 3 episcleral & limbal veins or episcleral area of right eye(HP group, n=25) and sham operation group with conjunctiva incision without coagulation(n=25). Group 2: HSP27 or dose-matched PBS was injected into the vitreous(V-HSP27 group, n=15;V-PBS group, n=15). Group 3: HSP27 and complete Freund's adjuvant or dosematched PBS was injected subcutaneously into the hind limb accompanied intraperitoneal injection of pertussis toxin [sensitized group(I-HSP27 group), n=15;I-PBS group, n=15)]. Group 4 was normal group without any treatment(n=5). IOPs of the rats were measured before, day 3, weeks 1, 2, 4, 6, and 8 after treatment. Paraffin-embedded sections were prepared for HE staining and RGCs apoptosis were detected by TUNEL. Anti-HSP27 level in serum and CSF were examined by ELISA. RESULTS: IOPs were elevated significantly in HP and V-HSP27, V-PBS groups(P<0.01) and positively related to anti-HSP27 levels in serum and CSFs. Anti-HSP27 levels in serum and CSF were elevated significantly in I-HSP27group compared to other groups(P<0.05). However, the IOPs did not show any relationship with the high-level antiHSP27 in serum and CSFs. RGC apoptosis were all elevated significantly in the HP, V-HSP27, V-PBS and I-HSP27 groups and also positively relative with anti-HSP27 level in serum and CSFs except that high-level of anti-HSP27 in the serum of I-HSP group.CONCLUSION: The increases of anti-HSP27 levels in serum and CSFs both promote IOP escalation and the increase of RGC apoptosis in retina when anti-HSP27 is at low level. The case of high-level anti-HSP27 is opposite and shows protective function in preventing IOP increase and RGC apoptosis.
