Carbon tetrachloride administration induces the expression of hypoxia inducible factor-1alpha in rat liver

Abstract

Background: There is now increasing evidence that HIF-1 is also responsive to a variety of non-hypoxic stimuli. However, the mechanisms by which these non-hypoxic stimuli induce HIF-1α are not completely known, yet, although some evidence points to a role of ROS as messengers regulating HIF activity. Objective: To determine the expression of HIF-1α in liver rat tissue induced by carbon tetrachloride under normoxic conditions, with or without N-acetylcysteine protection. Methods: Twenty-five male Sprague-Dawley rats were divided into 5 groups: normal control rats, normal rats orally administered with coconut oil (1 mL/200 g body weight) for 1 day, rats orally administered with CCl4 (0.55 mg/g body weight) for 1 day, rats injected i.v. with NAC (0.15 mg/g body weight) for 8 days and then orally administered with CCl4 (0.55 mg/g body weight) for 1 day, rats orally administered with CCl4 (0.55 mg/g body weight) for 1 day and then injected i.v. with NAC (0.15 mg/g body weight) for 2 days. The expression of HIF-1α mRNA was measured by real-time RT-PCR using the Livak method. The expression of HIF-1α protein was measured by ELISA assay. Results: The highest HIF-1α mRNA and protein expression found in the group treated by CCl4 and then was gradually lowered in the pre-NAC group, post-NAC group, control group, and last, in the oil group. Conclusion: Our study shows the effect of CCl4-treated rats under normoxic conditions increased the mRNA and protein HIF-1α. NAC post-treatment provide a better protective effect compared with NAC pre-treatment