Targeting Colon Luminal Lipid Peroxidation Limits Colon Carcinogenesis Associated with Red Meat Consumption.

Red meat is probably carcinogenic to humans (WHO/IARC class 2A), in part through heme iron-induced lipoperoxidation. Here, we investigated whether red meat promotes carcinogenesis in rodents and modulates associated biomarkers in volunteers, speculating that an antioxidant marinade could suppress these effects via limitation of the heme induced lipid peroxidation. We gave marinated or non-marinated beef with various degrees of cooking to azoxymethane-initiated rats, Min mice, and human volunteers (crossover study). Mucin-depleted foci were scored in rats, adenoma in Min mice. Biomarkers of lipoperoxidation were measured in the feces and urine of rats, mice, and volunteers. The organoleptic properties of marinated meat were tested. Fresh beef increased colon carcinogenesis and lipoperoxidation in rats and mice and lipoperoxidation in humans. Without an adverse organoleptic effect on meat, marinade normalized peroxidation biomarkers in rat and mouse feces, reduced peroxidation in human feces and reduced the number of Mucin-depleted foci in rats and adenoma in female Min mice. This could lead to protective strategies to decrease the colorectal cancer burden associated with red meat consumption. Cancer Prev Res; 11(9); 569-80. ©2018 AACR.

Salivary Composition Is Associated with Liking and Usual Nutrient Intake.

Salivary flow and composition have an impact on flavor perception. However, very few studies have explored the relationship between saliva, individual liking and usual dietary intake. The aim of our study was to evaluate the association of salivary flow and composition with both a liking for fat, saltiness and sweetness and the usual nutrient intake in an adult French population. Liking for fat, saltiness, and sweetness were inferred from liking scores obtained during hedonic tests on 32 food products among 282 French adults participating in the Nutrinet-Santé Study. Before assessing liking, resting saliva was collected. Standard biochemical analyses were performed to assess specific component concentrations and enzymatic activities. Dietary data were collected using three web-based 24 h records. Relationships between salivary flow and composition, sensory liking and nutrient intake were assessed using linear regression. Total antioxidant capacity was positively associated with simple carbohydrate intake (ß = 31.3, 95% CI = 1.58; 60.99) and inversely related to complex carbohydrate consumption (ß = -52.4, 95% CI = -87.51; -19.71). Amylolysis was positively associated with both total (ß = 0.20, 95% CI = 0.01; 0.38) and simple carbohydrate intake (ß = 0.21, 95% CI = 0.01; 0.39). Salivary flow was positively associated with liking for fat (ß = 0.14, 95% CI = 0.03; 0.25). Proteolysis was positively associated with liking for saltiness and for fat (ß = 0.31, 95% CI = 0.02; 0.59; ß = 0.28, 95% CI = 0.01; 0.56, respectively). Amylolysis was inversely associated with liking for sweetness (ß = -10.13, 95% CI = -19.51; -0.75). Carbonic anhydrase 6 was inversely associated with liking for saltiness (ß = -46.77, 95% CI = -86.24; -7.30). Saliva does not substantially vary according to a usual diet, except for carbohydrate intake, whereas the specific association between salivary flow/composition and sensory liking suggests the influence of saliva characteristics in food acceptance.