Protective effect of Modified Taohong Siwu Decoction on hypoxia injury to retinal Müller cells

AIM: To investigate the protective effect of Modified Taohong Siwu Decoction(MTSD)on hypoxia injury to retinal Müller cells rMC-1.METHODS: Retinal Müller cells rMC-1 were interfered with the MTSD drug-containing serum under hypoxia condition, and were randomly divided into control group(21%O2), hypoxia model group(1%O2), MTSD drug-containing serum low-dose(1%O2+5% medicated serum), medium-dose(1%O2+10% medicated serum)and high-dose(1%O2+15%medicated serum)groups. Cell viability was detected by CCK-8 method, and secretion of vascular endothelial growth factor(VEGF)and pigment epithelium derived factor(PEDF)was detected by ELISA. The protein expressions of p-STAT3, STAT3 and hypoxia-inducible factor-1α(HIF-1α)were detected by Western blot, and the gene expressions of VEGF, PEDF, STAT3 and HIF-1α were detected by real-time polymerase chain reaction(PCR).RESULTS: The viability of rMC-1 cells was significantly inhibited when cultured at 1%O2 for 48h compared with that of control group(P<0.05), while it was improved in both low and medium dose of MTSD groups(P<0.05). The viability of rMC-1 cells in high dose group was not improved in hypoxia condition(P>0.05). The low and medium doses of MTSD could reduce the protein expressions of VEGF in supernatant of rMC-1 cells under hypoxia condition(P<0.05), while the protein expressions of PEDF could not be increased(P>0.05). The above two dose groups down-regulated the protein levels of both p-STAT3 and HIF-1α(P<0.05), and the inhibition effect of low dose group was better than that of medium dose group(P<0.05). The medium dose of MTSD could up-regulate STAT3 protein level after hypoxia culture in rMC-1 cells(P<0.05). The low and medium doses of MTSD significantly down-regulated VEGF gene level(P<0.05)and up-regulated PEDF gene level after hypoxia culture in rMC-1 cells(P<0.05), and the function in the low dose group was superior to that in the medium dose group(P<0.05). The low dose of MTSD could down-regulate STAT3 and HIF-1α gene levels after hypoxia culture in rMC-1 cells(P<0.05).CONCLUSION: Probably by inhibiting the STAT3/HIF-1α pathway, the drug-containing serum of MDST down-regulated the expression of VEGF protein and gene in hypoxia-induced retinal Müller cells, rMC-1, up-regulated the gene expression of PEDF, and alleviated the hypoxia injury to the cells.