Objective To observe the retinal apoptosis of laser-induced retinal injury in mice after bone marrow mesenchymal stem cells transplantation. Methods Green fluorescent protein (GFP) labeled MSCs from C57BL/6 mice were cultured in vitro. A total of 135 C57BL/6 mice were divided into three groups including normal control group (15 mice), injured control group (60 mice) and MSCs treatment group (60 mice). Laser retinal injuries were induced by laser photocoagulation. One day after photocoagulation, 02 ml cell suspension, which contained 1times;106 GFP-MSCs, were injected into the mice in treatment group via tail vein, and the mice in injured control group were given equal volume of phosphate buffer solution. Animal were execute on three, seven, 14 and 21 days following laser damage. Hematoxylin and eosin (HE) staining was performed to assess the changes of injured retinas. The diameters of laser spots and areas with total loss of cells in outer nuclear layer (ONL) were analyzed by image processing software. The apoptosis of retinal cells was examined by terminal-deoxynucleoitidyl transferase mediated nick end labeling (TUNEL) staining. The migration of GFP-MSCs into the retina was observed by fluorescence microscope. Results HE staining showed that the retinal structures were integrated in normal control group. Retinal damages were observed both in injured control group and MSCs treatment group, but milder in the latter. Though the average diameter of area with total loss of cells in ONL of MSCs treatment group was less than the injured control group (t=5.769, P＜0.05), the diameters of laser spots show no difference (t=0.964,P＞0.05) on day three. Both the average diameter of laser spots (t=5.180, 5.417, 2.381) and area with total loss of cells in ONL (t=3.530, 3.224, 3.162) were less in the MSCs treatment group on day seven, 14 and 21 (P＜0.05). TUNEL staining shows that the apoptosis were decreased after MSCs transplantation on day three, seven, 14 and 21 (t=11.142, 7.479, 6.678, 3.953,P＜0.05). No apoptosis was observed in normal control group. Very few GFP-MSCs were observed in the retina at all time-points. They were only seen in the subretinal and choroidal neovascularization occasionally on day seven and 14. Conclusion MSCs transplantation can effectively limit the range of retinal laser damage and inhibit cell apoptosis.
Objective To observe the effects of subretinal transplantation of rat mesenchymal stem cells (rMSCs) on Sodium Iodate (SI)induced retinal degeneration. Methods One hundred and twenty BrownNorway (BN) rats were divided into three groups including SI injection group,rMSCs transplantation group and normal control group, each with 40 rats. The retinal degeneration was induced by caudal vein injection of SI. The retinal pigment epithelium（RPE）and neural retinal were evaluated by ocular fundus photograph, fluorescein fundus angiography (FFA)，electroretinogram (ERG) and histological approach, and TUNEL（terminal deoxynucleotidyl transferasemediated dUTP nick end labeling ）. CMDiIprelabeled primary rMSCs were transplanted into the subretinal space of SIinduced rats. The survival, integration, and differentiation of rMSCs were observed between 14 day to 60 day after the transplantation.Results The rat retinal function was gradually reduced after14 days of SI injection, with a timedependent manner. After the RPE cells were damaged，the outer segments of photoreceptors became disrupted and shortened until karyopyknosis. The nuclear morphology and positive TUNEL labeling indicated that the death of photoreceptor cells was apoptosis. After rMSCs transplantation, CMDiI labeled donor cells were observed to be scattered in the subretinal space and expressed RPE cell markers. Average amplitude of b wave and Ops (oscillation potential) in ERG improved 27.80%,59.38% respectively after rMSCs transplantation.Conclusions Transplanted rMSCs can survive in subretinal space and differentiate into RPE.
ObjectiveTo observe the effects of human umbilical cord mesenchymal stem cells (hUCMSCs) on blood glucose levels and diabetic retinopathy in diabetes mellitus (DM) rats. MethodA total of 45 healthy male Sprague-Dawley rats were randomly divided into normal control group (group A, 10 rats) and DM group (33 rats). Diabetic model was established in DM group by tail vein injection of streptozotocin.The DM group was further randomly divided into 3 groups (11 rats in each group), including group B (no transplantation), group C (hUCMSC was injected through tail vein) and group D (hUCMSC was injected into the vitreous). Blood glucose, retina wholemont staining and expression of brain derived neurotrophic factor (BDNF) in the retina were measured at 2, 4, 6, 8 weeks after hUCMSC injection. The blood glucose was significantly different between A-D groups before injection (t=-64.400, -60.601, -44.065, -43.872; P=0.000) BDNF expression was studied by real time fluorescence quantitative polymerase chain reaction (RT-PCR) and immunohistochemistry staining. ResultsThe blood glucose was significantly different between A-D groups after hUCMSC injection (F=400.017, 404.410, 422.043, 344.109; P=0.000), and between group C and group B/D (t=4.447, 4.990; P < 0.01). Immuno-staining shown that BDNF was positive in ganglion cell layer (RGC) of group A, weak in group B while BDNF expression increased in group C/D. BDNF mRNA expression was significantly different between group B, C and D at 4, 6 and 8 weeks after hUCMSC injection (F=29.372, 188.492, 421.537; P=0.000), and between group B and C/D (t=66.781, 72.401, 63.880, 88.423, 75.120, 83.002; P < 0.01) by RT-PCR analysis. The BDNF mRNA expression was significantly different between C and D groups only at 8 weeks after hUCMSC injection (t=127.321, P=0.005). ConclusionsTail vein injection of hUCMSCs can significantly reduce the blood glucose levels of rats. Intravenous and intravitreal injection of hUCMSCs can increase the expression of BDNF.
Objective To observe the effects of the bone marrow mesenchymal stem cells (BMSCs) on the expression of neurotrophic factor protein gene in the retinal detachment (RD) rabbits. Methods 60 healthy rabbits were randomly divided into control group (group A), retinal detachment with PBS group (group B), retinal detachment with BMSCs group (group C), 20 rabbits in each group. RD model were established for rabbits in group B and C. 10 μl PBS was injected into the subretinal space of rabbits in group B, while 10 μl CM-Dil labeled BMSC PBS was injected into subretinal space of rabbits in group C. The rabbits in the group A received no treatment. At 1, 2 and 4 weeks after modeling, the mRNA expression of basic fibroblast growth factor (bFGF), brain derived neurotrophic factor (BDNF) and ciliary neurotrophic factor (CNTF) were measured by real-time quantitative PCR. Results At 1, 2 and 4 weeks after modeling, the mRNA expression of bFGF, BDNF, CNTF on retinal tissue were increased significantly in group C as compared with group A and B (P < 0.01). At 1 week after modeling, the mRNA expression of bFGF and CNTF on retinal tissue were increased significantly in group B as compared with group A, the mRNA expression of BDNF on retinal tissue in group B was similar with group C. At 2 and 4 weeks after modeling, the mRNA expression of bFGF, BDNF, CNTF were decreased in group B as compared with group A. Conclusion Subretinal transplantation of BMSC can increase the mRNA expression of bFGF, BDNF and CNTF on retinal tissue in RD rabbits.
ObjectiveTo observe the influence of human umbilical cord mesenchymal stem cells (hUCMSC) transplantation into vitreous cavity of diabetic rats on the retinal morphology, and the expression of glial fibrillary acidic protein (GFAP) and rhodopsin (RHO). Methods78 male Sprague-Dawley rats were used. 70 rats were injected with streptozotocin by tail vein injection at a dose of 40 mg/kg to establish the diabetes mellitus model, and another 8 rats were injected with 0.1 mol/L pH 4.0 citric acid buffer at the same dose as the normal control group. After 6 weeks of modeling, 10 rats were taken as the control group of diabetic model. hUCMSC suspension was injected into the right eye vitreous cavity of the remaining 60 rats, and the same volume of Dulbecco's modified Eagle/F12 medium was injected into the left vitreous cavity as control eyes. 1, 2 and 4 weeks after transplantation, follow-up experiments were performed. The experimental eyes were labeled as U1, U2, and U4 groups, while the control eyes were recorded as D1, D2, D4, and each group consisted of 20 eyes. After paraffin section and hematoxylin-eosin staining, the structure of the retina was observed by optical microscopy and the thickness of the outer nuclear layer and the inner nuclear layer (INL) were measured. The distribution and migration of hUCMSC in rat retina were observed by frozen section-tissue immunofluorescence assay. The mRNA and protein expression of GFAP and RHO in the retina were detected by real-time quantitative polymerase chain reaction (PCR) and Western blot assays. ResultsThe results of optical microscope observation showed the normal structure of retina in normal control group. The retinal nerve fiber layer (NFL) was thinned and the number of retinal ganglion cells (RGC) in the control group of diabetic rats was decreased. The decreased number and disorder arrangement of RGC were observed as well in U1, D1 rats. The RGC number of U2, U4, D2, D4 rats was gradually decreased. Compared with D4 group, the thickness of INL in U4 group was significantly increased (P < 0.05). Tissue immunofluorescence assay showed that hUCMSC were distributed along the inner limiting membrane in the retina of the U1 group, while the number of hUCMSC in the U2 group was gradually decreased, mainly in the NFL and ganglion cell layers. Real-time PCR and Western blot data indicated that the relative expression of GFAP mRNA and protein in the diabetic retina was significantly increased, and the relative expression of RHO mRNA and protein decreased gradually in the diabetic model group and the D1, D2, D4 groups. Compared with D2 and D4 groups, the mRNA and protein expression of GFAP in U2 and U4 groups were decreased, and the relative expression of RHO mRNA and protein were all increased (P < 0.01). ConclusionhUCMSC could migrate and integrate into the retina, after the transplantation into the vitreous cavity of diabetic rats, which reduced the expression of GFAP, but enhanced the expression of RHO.