Yogurt Prevents Colorectal Tumorigenesis in ApcMin/+ Mice.

Abstract

Yogurt consumption is related to a decreased risk of colorectal cancer (CRC), but whether such association is causal remains unclear. Patients with familial adenomatous polyposis (FAP) are at increased risk of CRC development. Here, the study investigates the efficacy of yogurt for intestinal polyposis chemoprevention in ApcMin/+ mice, a preclinical model for human FAP. A 10-week yogurt supplementation (15gkg-1) in ApcMin/+ mice significantly reduces the intestinal polyp number (6.50±0.97 versus 1.80±0.49; p<0.001) compared to controls. 16S rRNA gene-based microbiota analysis suggests that yogurt supplementation may greatly modulate the gut microbiome composition, especially in the relative abundance of Lactobacillus and Bifidobacterium. Importantly, the fecal concentration of d-lactate (d-Lac, 0.39±0.04µmolg-1 versus 8.14±0.62µmolg-1; p < 0.001) is boosted by yogurt, while oral administration with d-Lac (125 or 250mgkg-1) reduces the polyp number by 71.43% or 77.14% (p<0.001), respectively. The study also observes that d-Lac does not affect cell viability and anchorage-independence in CRC cells, but it greatly suppresses epidermal growth factor (EGF) or 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced cell transformation in preneoplastic cells. Mechanistically, it demonstrates that d-Lac may attenuate epithelial cell transformation by targeting PI3K/AKT/β-catenin axis. Yogurt protects against intestinal polyposis in ApcMin/+ mice, and d-Lac may partially account for the chemopreventive effects above.