Downregulation of AMPK accompanies leucine- and glucose-induced increases in protein synthesis and insulin resistance in rat skeletal muscle.

ABSTRACT:

Objective

Branched-chain amino acids, such as leucine and glucose, stimulate protein synthesis and increase the phosphorylation and activity of the mammalian target of rapamycin (mTOR) and its downstream target p70S6 kinase (p70S6K). We examined in skeletal muscle whether the effects of leucine and glucose on these parameters and on insulin resistance are mediated by the fuel-sensing enzyme AMP-activated protein kinase (AMPK).

Research design and methods

Rat extensor digitorum longus (EDL) muscle was incubated with different concentrations of leucine and glucose with or without AMPK activators. Muscle obtained from glucose-infused rats was also used as a model.

Results

In the EDL, incubation with 100 or 200 μmol/l leucine versus no added leucine suppressed the activit

SUBMITTER: Saha AK 

PROVIDER: S-EPMC3279521 | biostudies-literature | 2010 Oct

REPOSITORIES: biostudies-literature