Dietary fat promotes intestinal dysregulation

In mice, a high-fat diet has now been found to induce intestinal progenitor cells to adopt a more stem-cell-like fate, altering the size of the gut and increasing tumour incidence. See Article p.53 How obesity-inducing diets modulate tissue stem cell function and influence pathologies such as cancer is not clear. This study shows that a high-fat diet increases the number of intestinal stem cells in mammals in vivo and in intestinal organoids treated with fatty acids. The authors find that a pathway involving peroxisome proliferator-activated receptor delta (PPAR-δ) confers organoid-initiating capacity to non-stem cells, and demonstrate that the pathway induces non-stem cells to form tumors in vivo following the loss of the Apc tumour suppressor.