High-fat diet-activated fatty acid oxidation mediates intestinal stemness and tumorigenicity

Cell Rep. 2021 Jun 8;35(10):109212. doi: 10.1016/j.celrep.2021.109212.

Abstract

Obesity is an established risk factor for cancer in many tissues. In the mammalian intestine, a pro-obesity high-fat diet (HFD) promotes regeneration and tumorigenesis by enhancing intestinal stem cell (ISC) numbers, proliferation, and function. Although PPAR (peroxisome proliferator-activated receptor) nuclear receptor activity has been proposed to facilitate these effects, their exact role is unclear. Here we find that, in loss-of-function in vivo models, PPARα and PPARδ contribute to the HFD response in ISCs. Mechanistically, both PPARs do so by robustly inducing a downstream fatty acid oxidation (FAO) metabolic program. Pharmacologic and genetic disruption of CPT1A (the rate-controlling enzyme of mitochondrial FAO) blunts the HFD phenotype in ISCs. Furthermore, inhibition of CPT1A dampens the pro-tumorigenic consequences of a HFD on early tumor incidence and progression. These findings demonstrate that inhibition of a HFD-activated FAO program creates a therapeutic opportunity to counter the effects of a HFD on ISCs and intestinal tumorigenesis.

Keywords: Apc; Cpt1a; Ppar; fatty acid oxidation; high-fat diet; intestinal stem cells.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Carcinogenesis / pathology*
  • Diet, High-Fat / adverse effects*
  • Fatty Acids / metabolism*
  • Humans
  • Intestines / pathology*
  • Mice
  • Obesity / physiopathology*
  • Oxidation-Reduction
  • PPAR alpha / metabolism*
  • Stem Cells / metabolism*

Substances

  • Fatty Acids
  • PPAR alpha