[Lycium barbarum polysaccharides enhances SIRT1 expression and decreases MMP-9 and HIF-1α expressions in hypoxic pulmonary vascular smooth muscle cells].

Objective To investigate the expressions of silent mating type information regulation 2 homolog-1 (SIRT1), matrix metalloproteinase-9 (MMP-9) and hypoxia inducible factor 1α (HIF-1α) in hypoxic pulmonary vascular smooth muscle cells (PVSMCs) treated with Lycium barbarum polysaccharides (LBP). Methods PVSMCs were divided into 10 groups: normal oxygen (200 mL/L oxygen) cells, 2 μmol/mL LBP-treated normal oxygen cells, DMSO-treated normal oxygen cells, DMSO-treated hypoxic (100 mL/L oxygen) cells, (0.5, 1, 2) μmol/mL LBP-treated hypoxic cells; SIRT1 agonist (resveratrol or SRT-1720)-treated hypoxic cells, SIRT1 inhibitor EX-527-treated hypoxic cells. After 6, 12, 24 hours, the mRNA and protein expressions of SIRT1, MMP-9 and HIF-1α were measured by real-time quantitative PCR and Western blotting, respectively. In LBP-treated groups, the expressions of SIRT1, MMP-9 and HIF-1α mRNA and protein were detected 12 hours after LBP treatment. Results Under the condition of hypoxia, the expression levels of SIRT1 mRNA and protein in PVSMCs decreased, while MMP-9 and HIF-1α mRNA increased. Under hypoxia, SIRT1 expression was raised and MMP-9, HIF-1α were reduced by LBP treatment in a dose-dependent manner. Morever, resveratrol could inhibit the expression of MMP-9. Conclusion LBP can enhance the expression of SIRT1 and decrease the expression of MMP-9 and HIF-1α in hypoxic PVSMCs.