Abstract: Ｏｂｊｅｃｔｉｖｅ：To study the mechanism of chronic hypoxia induced renal fibrosis.
Ｍｅｔｈｏｄｏｌｏｇｙ：Hypoxia induced renal tubular epithelial cells, the expression of HIF-1α, autophagy key molecules LC3Ⅰ/Ⅱ and P62 were measured by western blot, and microRNA-96(miR-96)was measured by PCR. HIF-1α siRNA and pcDNA-HIF-1α were transfected into renal tubular depithelial cells lines (HK-2) induced by hypoxia, and PCR was used to measure the expression of miR-96, and explore whether HIF-1α up-regulation affected the expression of miR-96. miR-96 mimic was transfected into HK-2 cells induced by normoxia, and western blot was used to measure the expression of fibrotic factor α-smooth muscle actin(α-SMA), Collagen4A1(COL4A1) and autophagy key molecules LC3Ⅰ/Ⅱ and P62. Mice were injected intraperitoneally with the viral vector of miR-96 inhibitor. The degree of renal fibrosis and the expression of fibrosis factor COL4A1 was detected by Masson staining.
Ｒｅｓｕｌｔｓ：Compared with normoxia group, hypoxia group showed significant increase of HIF-1α and miR-96 (P<0.05), and increase of autophagy key molecule LC3Ⅰ/Ⅱ and down-regulation of P62 (P<0.05). HIF-1α siRNA and pcDNA-HIF-1α were transfected into HK-2 induced by hypoxia, found that HIF-1α can promote the expression of miR-96. The up-regulation of miR-96 significantly increased the expression of fibrotic factor α-SMA and COL4A1 in normoxia condition, and increase of autophagy key molecule LC3Ⅰ/Ⅱ and down-regulation of P62 (P<0.05). The down-regulation of miR-96 significantly restrain the expression of LC3Ⅰ/Ⅱ and regain expression of P62 (P<0.05). Mice injected with the viral vector of miR-96 inhibitor intraperitoneally can inhibit the degree of renal fibrosis and the expression of the fibrosis factor COL4A1 in the (Unilateral Ureteral Obstruction, UUO) model compared with mice injected with the control virus.
Ｃｏｎｃｌｕｓｉｏｎ：HIF-1α/miR-96 signaling pathway induced abnormal autophagy of tubule epithelial cells, which caused the increase of pro-fibrotic factors and promotes renal fibrosis.

Key words: hypoxiahypoxia-inducible factor-1α, MicroRNA-96, autophagy, renal interstitial fibrosis