M arie M énard apples with high polyphenol content and a low‐fat diet reduce 1,2‐dimethylhydrazine‐induced colon carcinogenesis in rats: Effects on inflammation and apoptosis

Inflammation may increase cancer risk, therefore, we studied whether polyphenol‐rich Marie Ménard ( MM ) apples with reported anti‐inflammatory activity prevent 1,2‐dimethylhydrazine ( DMH )‐induced colon carcinogenesis in rats and, likewise whether high‐fat ( HF ) diet promoting carcinogenesis, may affect inflammation. DMH ‐induced rats were fed for 15 weeks with: an HF diet (23% corn oil w/w); an HF diet containing 7.6% w/w lyophilized MM (apple diet ( AD )); a low‐fat ( LF ) diet and an HF diet containing piroxicam ( PXC ) (0.01% w/w) as control. Mucin depleted foci ( MDF ), precancerous lesions in the colon, were dramatically reduced in the AD , LF , and PXC groups compared with the HF . Peritoneal macrophage activation, an index of systemic inflammation, was significantly decreased in the AD , LF , and PXC groups. TNF ‐ α , i NOS , IL ‐1β , IL ‐6 m‐ RNA expression in the colon, as well as CD 68 cells and plasmatic PGE 2 were lower in the AD , but not in the LF group. Apoptosis in the MDF of both the AD and LF ‐fed rats was significantly higher than in HF rats. In conclusion, AD has a strong chemopreventive effect, reducing inflammation, and increasing apoptosis, while the chemopreventive effect of the LF diet seems mediated mainly by increased apoptosis in MDF .