[Effect of hypoxia on the activation and visfatin expression in rat hepatic stellate cells].

OBJECTIVE: To investigate the effect of hypoxia on the visfatin and the expression of smooth muscle-actin (alpha-SMA) and hypoxia-inducible factor-1alpha (HIF-1alpha) in rat hepatic stellate cells (HSCs).
METHODS: Rat primary HSCs were isolated from SD rats by in situ perfusion of collagenase and pronase and single-step Nycodenz density gradient centrifugation, and then cultured and activated. Completely activated primary HSCs were exposed to hypoxic conditions (37 degrees C, 5% CO2, 1% O2, 94% N2), or normoxic conditions (37 degrees C, 5% CO2, 21% O2, 74% N2), for 3, 6, 12 or 24 h respectively. The expression of alpha-SMA, the marker of HSC activation, and visfatin were assessed by Real time-PCR and Western blot. The Expression of HIF-1alpha was detected by Real time-PCR.
RESULTS: HIF-1alpha mRNA in rat HSCs was induced after exposed to hypoxia for 3 h, and maintained elevated status up to 24 h. HSCs exposed to 1% O2 hypoxic conditions for 6 h increased alpha-SMA mRNA and protein expression. Visfatin mRNA expression was up-regulated after subjected to hypoxia for 12 h, and protein level was elevated after 6 h hypoxia. A positive linear correlation existed between alpha-SMA and visfatin expression in responsible to hypoxia (r = 0.991 (genes) and r = 0.968 (proteins), P < 0.05).
CONCLUSION: Microcirculation impairment could significantly induce alpha-SMA and visfatin expression in rat HSCs, which might potentate the activation process of HSCs.