Mechanism Underlying the Role of HIF-1αduring Hepatocyte Apoptosis in Intermittent Hypoxia with Pulmonary Emphysema in Rats / 天津医药

ABSTRACT

Objective To investigate the effect of intermittent hypoxia (IH) with pulmonary emphysema on the ex-pression of hypoxia inducible factor-1α(HIF-1α),Bax and Bcl-2, and the mechanism underlying the role of HIF-1αin he-patocyte apoptosis thereof. Methods Sixty rats were randomly divided into four groups: normal control group, rats were treated normally;IH group, rats were treated by 30 s nitrogen and then 90 s air, and rats were treated by from 9:00-17:00 daily;pulmonary emphysema group, rats were treated by smudging for half an hour, twice a day (8:00 and 18:00);IH with pul-monary emphysema group, rats were treated by 30 s nitrogen and then 90 s air from 9:00-17:00 daily. After exposure four-teen weeks, rats were killed. qRT-PCR assay was conducted to detect the expression of HIF-1α mRNA, Bax mRNA and Bcl-2 mRNA in live tissues. Results The expressions of HIF-1αmRNA, Bax mRNA and Bax/Bcl-2 were significantly higher in IH with pulmonary emphysema group than those in control group,IH group and pulmonary emphysema group (P0.05). The levels of HIF-1αand Bax were positively correlated with the level of Bax/Bcl-2 (r=0.732 and 0.699),but the lev-els of HIF-1αand Bax were negatively correlated with the level of Bcl-2 (r=-0.705). Conclusion The expression levels of HIF-1αmRNA, Bax mRNA and Bcl-2 mRNA were over-regulated in hepatocytes induced by intermittent hypoxia with pul-monary emphysema. The HIF-1αexpression was correlated with Bax and Bcl-2, suggesting that HIF-1αmay promote the hepatocyte apoptosis through transcriptional co-activators, Bax and Bcl-2.