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Objective To study the effect of pirfenidone (PFD) on the transformation of rat corneal stromal cells into fibroblasts in vitro and further explore the anti-fibrotic effect of PFD. Methods The corneal stromal cells from SD rat was isolated and cultured ,and was determined by vimentin stain. The experiment was divided into control group(DMEM+10%FBS),TGF-β1 group(2 ng/mL TGF-β1+DMEM+10%FBS)and PFD group(1 mg/mL PFD+ 2 ng/mL TGF-β1+DMEM+ 10%FBS). Cell proliferation was detected by CCK-8 assay. Collagen Ⅰ,Collagen Ⅲ,Keratocan and CD99 expression were detected by Western blot. Results Compared with control group and TGF-β1 group,the cell proliferation were significantly decreased in PFD group(P<0.05). Western blot showed that PFD can up-regulated Collagen Ⅰand Keratocan but down-regulated Collagen ⅢCD90 expression(P < 0.05). The ratio of Collagen Ⅲ/Collagen Ⅰ in PFD group was lowest in all groups(P < 0.05). Conclusion PFD can resistant fibration in corneal stromal cells may through the inhibition of TGF-β ,which affect the collagen synthesis and Keratocan,CD90 expression.
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AIM:To investigate the effects of estrogen on the expression of matrix metalloproteinases-2(MMP-2), tissue inhibitor of metalloproteinases-2(TIMP-2) and transforming growth factor-β1(TGF-β1) in cultured human corneal stromal cells.METHODS: Inflammatory environments of human corneal stromal cells were simulated by using 1.5ng/mL IL-1β.The cells were then treated with or without different concentrations of estrogen(0, 1×10-4, 1×10-6, 1×10-8, 1×10-10mol/L estradiol)in vitro.Cell viability was evaluated by MTT.Expression levels of MMP-2, TIMP-2 and TGF-β1 proteins were measured by enzyme-linked immunosorbent assay(ELISA).RESULTS:Estrogen did not affect the viability of human corneal stromal cells.Compared with the control group, expression levels of MMP-2 and TGF-β1 proteins in E2 treatment group significantly decreased after being treated with estrogen, while the expression level of TIMP-2 significantly increased.CONCLUSION: Estrogen could, to some extent, down-regulate the expression of MMP-2 and TGF-β1 and up-regulate the expression of TIMP-2, which might contribute to protecting human cornea.
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Background Recent researches show that oxidative stress is involved in the progress of keratoconus.Nuclear factor-E2-related factor 2-antioxidant response element (Nrf2-ARE) pathway plays a critical role in the defense against oxidative stress,but its function in keratoconus is unclear.Objective To investigate the differences of Nrf2-ARE signaling activation and matrix degenerating enzymes between keratoconus and normal corneal stromal cells.Methods Corneal stromal cells were isolated from keratoconus and normal cornea by using dispase and collagenase digestion.The cells were treated with hydrogen peroxide (H2O2) to mimic in vivo oxidative stress condition.Reactive oxygen species (ROS) production was measured by fluorescence substrate DCHF-DA incubation.Nrf2 level and the expression of Nrf2-ARE downstream antioxidant genes were analyzed by Western blot and real-time quantitative-PCR(RT-qPCR).The activity of matrix degenerating enzymes,including urokinase-type plasminogen activator (uPA)-uPA receptor (uPAR) system and matrix metalloproteinase-2 (MMP-2) were assessed by Western blot and gelatin zymography respectively.Results In normal culture,keratoconus corneal stromal cells assumed increased basal ROS and Nrf2 level when compared with normal cells(t =18.155,P＜0.01).However,after H2O2 treatment,the keratoconus corneal stromal cells showed increased ROS production,while decreased Nrf2 translocation and no significant difference in expression levels of Nrf2-ARE downstream antioxidant genes (Nrf2:t =62.123,P＜ 0.01 ; (nicotinamide adenine dinucleotide phosphate quinine oxidoreductase-1 [NQO-1]:t =2.209,P =0.092 ; hemo oxygenase-1 [HO-1]:t =0.293,P =0.784 ; superoxide dismutase [SOD2]:t =0.749,P =0.495).The contents of uPA-uPAR and the activity of MMP-2 also showed a higher level in keratoconus corneal stromal cells than normal cells,with significant differences between them (t =19.164,15.458,4.818,all at P＜0.01).Conclusions The defect of Nrf2-ARE signaling activation exists in the keratoconus corneal stromal cells,and correlats with the abnormal expression level of stromal degeneration enzymes,which suggests that the defect of Nrf2-ARE signaling activation may be involved in the progression of keratoconus.
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Background Clinical studies indicated that the pathogenesis of most corneal dystrophy is associated with the mutation of the transforming growth factor beta-induced (TGFBI) gene.However,the molecular mechanism of mutated TGFBI gene in corneal dystrophy is unclear. Objective The present study was to investigate the expression of the TGFBI gene in human corneal tissue and cells in vitro.MethodsHuman corneal epithelial cells and keratocytes were cultured and passaged,and donor corneal tissue was obtained for the section preparation.RT-PCR was used to detect the expression of TGFBI mRNA in human corneal tissue and cells.Immunofluorescence was used to test the expression of the TGFBI protein in the human corneal tissue,and immunohistochemistry was used to test the expression of the TGFBI protein in human corneal epithelial cells and corneal stromal cells.ResultsRT-PCR analysis showed that TGFBI mRNA could be detected as a 1274 bp band in human corneal tissue and corneal stromal cells,but no TGFBI mRNA was observed in corneal epithelial cells.Immunofluorescence assay revealed that corneal stromal cells were positive ly expressed for the TGFBI protein,but the corneal epithelial cells did not express the TGFBI protein.Immunohistochemistry indicated that the expression of TGFBI was detected the red fluoressence in the cytoplasm of corneal stromal cells;however,no positive response was found in corneal epithelial cells.ConclusionsThe expression of the TGFBI gene occurs in human corneal stromal cells but not in the corneal epithelial cells.This result might be of helpful for studying the function and role of TGFBI gene in pathogenesis of corneal dystrophy.