Objective: To establish an interventional model of knockdown Kelch-like ECH-associated protein 1 (Keap1) in hepatocytes and investigate the influence of hypoxic hepatocytes with Keap1 knock-down on the matrix metalloproteinase-2 (MMP-2), and the corresponding regulatory molecules such as matrix metalloproteinase inhibitor (TIMP-2), membrane-type 1 matrix metalloproteinase (MT1-MMP or MMP14), caveolin-1 (Cav-1) of the hepatic satellite cells(HSCs). Methods: According to the method established by our group, the hepatocytes with Keap1 knock-down was constructed, and were cultured under hypoxic conditions. The expression levels of Keap1 and nuclear factor erythroid 2 related factor 2 (Nrf2), tumor necrosis factor-α (TNF-α) its downstream molecules of the hepatocytes were measured by Western blotting and QPCR. Hepatic stellate cells(HSC-T6) were cultured in the above-mentioned hepatocyte culture supernatant, then HSC-T6 cells and culture supernatant were collected. Expression of Keap1, Nrf2 and MMP-2 of the HSC-T6 cells were detected by Western blotting, the activity of MMP-2 in supernatant of HSC-T6 cells was measured by gelatin zymography. Results: After stable knock-down of Keap1,the expression of Nrf2 was increased and the expression of TNF-α was decreased in the hepatocytes. Compared with the control group,the culture supernatant of hepatocytes with Keap1 knock-down reduced the expression of MMP-2, Cav-1, MT1-MMP, TIMP-2 protein and increased the activity of MMP-2 in HSC-T6 cells. Conclusion: When hepatocytes with Keap1 knock-down are under hypoxic conditions, the degree of hepatocyte injury is reduced, and the synthesis and release of TNF-α are decreased,which may reduce the stimulation of Cav-1 in endocytic molecules of HSC-T6 cells. Cav-1 interferes with MMP-2 activation on the membrane surface, in this condition the MMP-2 activity is increased.
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