Objective To observe the effect of cyanin on the expression of L-glutamate/L-aspartate transporter (GLAST) in high glucose cultured retina Muuml;ller cells. Methods The retinal tissue of Sprague-Dawley (SD) rats was collected at postnatal 10 day, and Muuml;ller cells were isolated and cultured according to literature. The Muuml;ller cells (2nd 4th generations) were treated with five different medium as normal group (group A), high glucose control group (group B), high glucose＋30 mu;mol/L cyanin group (group C), high glucose＋60 mu;mol/L cyanin group (group D) and high glucose＋100 mu;mol/L cyanin group (group E). Cell relative survival rates (A value) were measured by MTT assay at 570 nm.The GLAST protein expression in Muuml;ller cells was observed by Western blot. Results MTT assay showed that the A value of the five group were 0.450 8plusmn;0.020 4, 0.270 1plusmn;0.031 4, 0.332 0plusmn;0.023 2, 0.428 3plusmn;0.017 2, 0.361 9plusmn;0.027 0,the cell relative survival rate were 100.0%, 59.9%, 73.6%, 95%, 80.3% respectively. The A value of group C，D，E were significantly higher than that of group B (F=32.25,P＜0.05)，the A value of group D were significantly higher than that of group C and E (F=21.07,P＜0.05).Western blot showed that the GLAST protein expression of group B was lower than that of group A (t=5.25,P＜0.05)；there was no obvious changes of GLAST protein expression in group A，C，D and E (F=2.979, P＞0.05). Conclusion Cyanin can rescue high glucose induced GLAST reduction.
ObjectiveTo observe the protective effect of Zhicao Tea Mixture on Müller cells and the expression of inflammatory factors in mice with diabetic retinopathy.MethodsSeventy-five C57BL/6J mice were randomly divided into the normal control group, diabetes mellitus (DM) group, low concentrations group, medium concentrations group and high concentrations group, with 16 mice in each group. The diabetes model of mice in all groups except the normal control group were established by intraperitoneal injection of STZ (60 mg/kg). Four weeks after the successful modeling, the Zhicao Tea Mixture with low (30 ml/kg), medium (60 ml/kg) and high concentrations (120 ml/kg) were respectively administered by gavage. Weight and blood glucose of mice in each group were measured every two weeks. After 8 weeks, Western blot method was used to detect the mice retina Müller cells activation marker gelatinous fibrous acidic protein (GFAP). Immunofluorescence was performed to detect the expression GFAP and glutamine synthetase (GS). Real-time quantitative PCR (RT-qPCR) and ELISA were used to determine the mRNA and protein expression levels of mouse retinal VEGF, TNF-α, IL-1β and IL-6 respectively.ResultsThe weight of mice in the DM group was lower than that of the normal control group, and the blood glucose was increased. Zhicao Tea Mixture had no effect on the weight of DM mice, but had a significant hypoglycemic effect. The GFAP expression (t=38.318, P＜0.001) in the retina of mice in the DM group was increased and GS expression (t=29.737, P＜0.001) was decreased compared with the control group. The GFAP expression (t=13.677, 19.387, 16.305; P＜0.05) in the retina of mice in the low, medium and high concentrations group were decreased and GS expression (t=5.170, 19.399, 6.705; P＜0.05) were increased compared with the DM group. The expressions of retinal inflammatory factors VEGF, TNF-α, IL-1β and IL-6 in DM group all increased, while the expressions of the above-mentioned inflammatory factors in the retina of mice decreased in the low, medium and high concentrations group.ConclusionZhicao Tea Mixture can decrease the blood glucose of DM mice and reduces the diabetic retinal inflammatory response.
ObjectiveTo observe the effect of tert-Butylhydroquinone (tBHQ) on the expression of nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase (HO)-1 and phosphatidylinositol 3-kinase (PI3K) in high glucose cultured retinal Müller cells; and to investigate the anti-oxidative stress and anti-apoptotic effects of tBHQ.MethodsRetinal Müller cells were divided into normal glucose group (5.5 mmol/L, N group), high glucose group (45 mmol/L, HG group) and tBHQ intervention group (HG+tBHQ group). After retinal Müller cells were cultured with high glucose for 48 hours, the pretreatment with tBHQ (20 μmol/L) induced the expressions of nuclear factor erythroid 2-related factor 2 (Nrf2) and HO-1. The Müller cells were identified by immunofluorescence staining. The expressions of Nrf2, HO-1, PI3K, B-cell lymphoma-2 (Bcl-2) and Bax were detected by Western blot and real-time fluorescence quantitative PCR. Flow cytometry was used to detect the apoptosis of retinal Müller cells in rats.ResultsMüller cytoplasm and nucleus GS showed strong positive, large cell body, abundant cytoplasm, uniform green fluorescence; nuclear DAPI staining round or oval, clear boundary. The expression of Nrf2 protein (t=4.114, P=0.006), HO-1 protein (t=9.275, P=0.000), Nrf2 mRNA (t=7.292, P=0.000) and HO-1 mRNA (t=15.014, P=0.000) in the HG group were higher than those in the N group. The expressions of Nrf2 protein (t=7.847, P=0.000) ,HO-1 protein (t=7.947, P=0.000), PI3K protein (t=5.397, P=0.002), Bcl-2 protein (t=6.825, P=0.000), Nrf2 mRNA (t=18.046, P=0.000), HO-1 mRNA (t=39.458, P=0.000), PI3K mRNA (t=4.979, P=0.003) and Bcl-2 mRNA (t=9.535, P=0.000) in the HG+tBHQ group were significantly higher than those in the HG group. The protein and mRNA expressions of Bax protein in the HG+tBHQ group were significantly lower than those in the HG group (t=14.998, 16.520; P=0.000, 0.000). Flow cytometry showed that the apoptosis rate of Müller cells in the HG group was significantly higher than that in the N group (t=39.905, P=0.000). The apoptosis rate of Müller cells in the HG+tBHQ group was significantly lower than that in the HG group (t=21.083, P=0.000).ConclusiontBHQ can inhibit the apoptosis of retinal Müller cells by up-regulating the expression of Nrf2, HO-1 and PI3K.
Objective To investigate the effect of hypoxia on expressions of erythropoietin（EPO）mRNA and protein in retinal Muuml;ller cells cultured in vitro. Methods Retina tissues from the new-born Wistar rats were dissected into cell suspension after digested by pancreatin.Muuml;ller cells were separated and purified by mechanical concussion and blowing and striking method.The expression of EPO mRNA and protein under the condition of hypoxia was detected by semi-quantitative reverse transcriptase（RT）-polymerase chain reaction（PCR）and immunocytochemical method. Results Retinal Muuml;ller cells were cultured successfully，95% of which were positively stained by glial fibrillary acidic protein（GFAP）.Positively stained EPO protein was located in the cytoplasm and protuberance.The expression of EPO mRNA and protein was faint in the normal retinal Muuml;ller cells，but increased obviously and time-dependently after hypoxia. Conclusion Expression of EPO mRNA and protein increases in Muuml;ller cells after hypoxia，which may be one of the protective factors for the nerves in anoxic retinopathy. (Chin J Ocul Fundus Dis, 2006, 22: 196-199)
Obiective lt;brgt;To investigate the change of the activity of proliferation in cultivated Muuml;ller cells treated by advanced glycation endoproducts (AGEs), and the effect of these changes on expression of occludin in bovine retinal vascular endothelial cells (BREC). lt;brgt;Methods lt;brgt;The cultivated Muuml;ller cells were devided into normal growth group and cultured with AGEs group. The cultured BREC were devided into 4 groups:group 1, without any medium; group 2, with normal growth Muuml;ller cell medium (MCM); group 3,MCM treated by AGEs; group 4, without cell as the control. Enzyme-linked immuno sorbent assay was used to detect the content of occludin in the medium in the 4 groups. lt;brgt;Results lt;brgt;The content of expression of occludin was the most in group 2, less in group 1, and the least in group 3. lt;brgt;Conclusion lt;brgt;AGEs may promote the abnormal proliferation of Muuml;ller cells and inhibit the expression of occludin in BREC. lt;brgt;(Chin J Ocul Fundus Dis, 2006, 22: 28-30)
Objective To investigate the effect of methylprednisolone on the expression of glial fibrillary acidic protein (GFAP) and proliferating cell nuclear antigen (PCNA) in Müller cells of rats’ retinae injured by laser. Methods Forty SD rats were randomly divided into two groups and inflicted with laser photocoagulation.The rats in treatment group were given methylprednisolone by intraperitoneal injection with a dose of 30 mg/kg for 3 days.At the 3rd,7th,14th,and 28th day after photocoagulation respectively, the eyes were enucleated,fixed and cut into sections.Immunohistochemical examination was used to detect the expression of PCNA and GFAP. Results After photocoagulation the Müller cells expressed PCNA both in the treatment and control group,and the expression of PCNA decreased sharply after 3 days. The expression of PCNA in treatment group was less than that in control group. After photocoagulation the Müller cells also expressed GFAP and the expression of GFAP lasted for at least 28 days ,and the expression of GFAP expression in the treatment group was less than that in the control group. Conclusion Methylprednisolone can reduce the expression of GFAP and PCNA in Müller cells of rats’ retinae injured by laser. (Chin J Ocul Fundus Dis, 2002, 18: 299-301)
Objective To investigate the effect of peritoneal exudative cells as feeder cells on growth state of primary culture of adult rat retinal Muuml;ller cells. Methods Peritoneal exudative cells were gained from adult rats, which were identified with specifically biological marker of macrophage (CD68). The phagocytosis was evaluated by the ink particles experiment. Retinal Muuml;ller cells of adult rats were cultured by enzyme digestion method, and identified by GFAP and vimentin immunocytochemically. As the feeder cells, peritoneal exudative cells were cocultured with Muuml;ller cells. The proliferation cycle of Muuml;ller cells was assayed by flow cytometry. One-step TUNEL staining was employed to detect the apoptotic Muuml;ller cells. Results Over ninety-five percent of rat peritoneal exudative cells were macrophage, which have a favourable phagocytic ability for the ink particles. The primary cultured Muuml;ller cells adhered to the wall of flask and grew fast, with large applanate cell bodies. The third-generation cells grew slowly. After cocultured with feeder cells, the Muuml;ller cells showed more rapid growth rate with more cells in S and G2/M phase(S phase, t=4.172, Plt;0.001; G2/M phase, t=3.562, Plt;0.01） and less apoptotic rate (t=3.804, Plt;0.01). The growing cycle was cut down from 25-30 days to 1822 days for the firstgeneration cells, from 10-15 days to 7-10 days for the second-generation cells. Conclusion It is an effective method to use the peritoneal exudative cells as feeder cells cocultured with primary culture of retinal Muuml;ller cells, which can shorten the culture period of Muuml;ller cells in adult rats.
Objective To study the effects of connective tissue growth factor (CTGF) on retinal Müller cells based on transcriptome analysis of RNA-seq technology.MethodsRetinal Müller cells were divided into the control group and the CTGF treatment group which was continuously cultured with 10 ng/ml of CTGF for 24 h. The influence of CTGF on the migration of Müller cells were tested by scratching experiments. The RNA transcriptome analysis was applied to complete transcriptome sequencing, differentially expressed genes and functional enrichment analysis of the two groups of cells. HiSeq sequencing technology was used to sequence the whole transcriptome of the two groups of cells to obtain biological big data, and analyze the differentially expressed miRNAs on this basis. The functions and signal pathways of differential miRNAs were analyzed through gene annotation (GO) functional significance enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway significant enrichment analysis. Based on transcriptome data, genes with differential expression multiples in the top ten between the two groups were screened out, and the expression of bone morphogenetic protein 4 (BMP4) gene was verified by real time fluorescence quantification PCR (qRT-PCR), immunofluorescence and Western blot.ResultsAfter CTGF stimulation of Müller cells, cell viability and mobility which compared with the control group were significantly increased, with statistically significant differences (t=3.453, P＜0.05). The differential gene expression profile of CTGF induced Müller cells was obtained by RNA transcriptome analysis. Comparing the sequencing results of the two groups, it was found that 325 differentially expressed genes included 152 up-regulated genes and 173 down-regulated genes. The results of GO functional significance enrichment analysis showed that the functions of differential miRNA were mainly divided into three categories: biological processes, cellular components, and molecular functions. These differentially expressed genes were involved in signaling between nervous systems, adhesion between cells, and the interaction between cytokines and their receptors. These differentially expressed genes were involved in different metabolic pathways and biological processes such as tissue inflammation and fibrosis. BMP4 gene was seected for verification through immunofluorescence, qRT-PCR and western blot. The results showed that the expression of BMP4 was significantly higher than that in the control group, and the difference was statistically significant (t=39.490, 10.110, 5.470; P=0.004, 0.001, 0.006).ConclusionCTGF promotes cell proliferation and migration by up-regulating the expression of BMP4 in Müller cells, leading to tissue fibrosis and inducing inflammation.
Objective To observe the different effect such as high concentration of glucose and high concentration of insulin on GLUT1 of Rabbit Retinal Muuml;ller Cell in vitro. Methods Rabbit retinal Muuml;ller cells were cultured in vitro with suspended constitution，which were divided as the following groups: common control group，high glucose group，insulin group，high glucose combined insulin group. Laser confocal microscope combined with immunocytochemical and fluorescence staining method to quantitatively analyze the expression condition of GLUT1. Results The expression of GLUT1 has been enhanced obviously by high glucose and high insulin，which locates mainly in the cytoplasm that near to the nucleus. Conclusion Rabbit retinal Muuml;ller cells can express GLUT1，and the expression of GLUT1 can be reinforced by high glucose and high insulin. （Chin J Ocul Fundus Dis，2008，24：265-267）
Müller cells are glial cells of the retina, whose major processes cross the internal and external limiting membranes of the retina, maintaining the function and metabolism of retinal photoreceptors and neurons. Their structure and function are closely related to the development of macular hole (MH). Müller cells are involved in the formation and recovery of MH from the aspect of traction and protein, and their morphology and biological function also influence the regression of MH. The current treatment modality for MH is vitrectomy combined with internal limiting membrane (ILM) peeling, in which Müller cells play a dual role after ILM peeling in different stages of MH. And its potential to re-acquire a progenitor-like state following retinal injury with the ability to proliferate and generate new neurons making it a current research hot topic, which can be a reference and inspiration for clinical treatment.