Original Article Effects of simulated weightlessness on liver Hsp70 and Hsp70mRNA expression in rats
Yan Cui, Jinlian Zhou, Chenglin Li, Ping Wang, Ming Zhang, Zipei Liu, Yong Yi, Jianzhong Zhang
Department of General Surgery, 306 Hospital, Beijing, China; Department of Pathology and Laboratory Medicine, 306 Hospital, Beijing, China; Department of Clinical Laboratory, 306 Hospital, Beijing, China.
Received January 2, 2010; accepted January 6, 2010, available online January 10, 2010
Abstract: Space flight is known to induce a number of hepatic physiological alterations. In this study, we investigated Hsp70 expressing features of rat liver under simulated weightlessness. Tail-suspension was used to simulate the weightlessness animal model. Forty-eight male Wistar rats were randomly assigned to 6 experimental groups and Hsp70 protein and mRNA expressions in the liver were detected by Western blot and RT-PCR respectively. The tailsuspension significantly increased Hsp70mRNA expression levels in rat liver (P<0.05). The semi-quantitative PCR showed that Hsp70mRNA was upregulated as early as 6 hours of suspension. Western blot analysis indicated that Hsp70 protein was significantly upregulated in the early stage of suspension as compared with controls (P<0.05). The results suggest that simulated weightlessness acts as a kind of stress to elevate liver Hsp70 expression both at protein and mRNA levels. This may be meaningful in astronaut’s trainings by preadaptation to non-damaging stress exposures or other environmental factors to foster the astronaut’s ability of weightless tolerance. (IJCEM1001001).
Key words: Hsp70, simulated weightlessness, rats, liver, RT-PCR, Western blotting