Effect of β-guanidinopropionic acid on the lifespan of drosophila and the underlying mechanism

摘要

Aim β-guanadinopropionic acid （β-6PA）, a creatine analog has been demonstrated to lead to thechronic activation of AMPK with increasing mitochondrial biogenesis. However, little is known about the effect of β-GPA on lifespan extension. In current study, we explore whether β-GPA produces the lifespan extension in adult Drosophila and underlying mechanism. Methods The flies were fed in a normal chow diet containing different concentrations （300 raM,900 mM,2700 mM）of β-GPA. Western blot was also used to investigate protein expres- sions. RNA interference was employed to examine effects of lifespan in Drosophila by 13-GPA. Results 900 mM and 2700 mM β-GPA significant extended the lifespan and activated AMPK both in male and female Drosophila with elevated level of autophagy. We found that Atg8 was significantly upregulated and P62 was significantly down- regulated by 900 mM 13-GPA, on the other hand, when the expression of Atg5 protein, an essential protein for au- tophagy, was reduced by RNAi, the effect of β-GPA on lifespan extension was abolished. Inhibition of AMPK by either AMPK-RNAi or compound （2, significantly attenuated the expression of autophagy-related proteins and lifes- pan extension in Drosophila. We found that the activation of AMPK induced by β-GPA inhibited mTORC1 activity, implicating that mTORC1 may not prevent the activation of ULK1/Atgl by AMPK. Conclusion β-GPA can ex- tend the lifespan of Drosophila and this effect is mediated by AMPK-Atgl dependent autophagy.