Selective mTORC1 inhibition to prevent and treat NAFLD and NASH

As many as 100 million people in the US have non-alcoholic fatty liver disease (NAFLD), which can lead to hepatic injury and fibrosis, characteristics of non-alcoholic steatohepatitis (NASH), and in turn can progress to cirrhosis and hepatocellular carcinoma cancer (HCC). To date there are no FDA-approved therapy for NAFLD or NASH. The mTOR pathway is a critical nutrient sensing pathway in many cell types, including hepatocytes. mTORC1 has thus been studied as a target to modulate lipid homeostasis in the liver, but its role remains unclear, with multiple excellent studies lead to seemingly opposing conclusions. We have now uncovered a highly specific branch of mTORC1 signaling in the liver, regulated by the FLCN protein, the inhibition of which leads to coordinated activation of lipid catabolic pathways and strong suppression of de novo lipogenesis (DNL), thereby potently protecting from both NAFLD and ensuing NASH.

We thus hypothesize that FLCN represents a uniquely attractive therapeutic target to treat these diseases. We propose experiments to: 1. Understand how, mechanistically, the FLCN arm of mTORC1 signaling suppresses DNL 2. Understand how, mechanistically, the FLCN and canonical arms of mTORC1 signaling feedback on each other 3.

Formally test the validity of FLCN as a therapeutic target to treat the NAFLD/NASH/HCC spectrum.

Grant Number: 5R01DK107667-10
NIH Institute/Center: NIH
Principal Investigator: Zoltan Arany