Impaired lipid accumulation in the liver of Tsc2-heterozygous mice during liver regeneration.

Tuberin is a negative regulator of mTOR pathway. To investigate the function of tuberin during liver regeneration, we performed 70% hepatectomy on wild-type and Tsc2+/- mice. We found the tuberin phosphorylation correlated with mTOR activation during early liver regeneration in wild-type mice. However, liver regeneration in the Tsc2+/- mice was not enhanced. Instead, the Tsc2+/- livers failed to accumulate lipid bodies, and this was accompanied by increased mortality. These findings suggest that tuberin plays a critical role in liver energy balance by regulating hepatocellular lipid accumulation during early liver regeneration. These effects may influence the role of mTORC1 on cell growth and proliferation.