Cocoa polyphenols and fiber modify colonic gene expression in rats

Abstract

Purpose Cocoa intake has been associated with health benefits, improving cardiovascular function and metabolism, as well as modulating intestinal immune function. The aim of this study was to take an in-depth look into the mechanisms affected by the cocoa intake by evaluating the colonic gene expression after nutritional intervention, and to ascertain the role of the fiber of cocoa in these effects.MethodsTo achieve this, Wistar rats were fed for 3 weeks with either a reference diet, a diet containing 10 % cocoa (C10), a diet based on cocoa fiber (CF) or a diet containing inulin (I). At the end of the study, colon was excised to obtain the RNA to evaluate the differential gene expression by microarray. Results were validated by RT-PCR.ResultsThe C10 group was the group with most changes in colonic gene expression, most of them down-regulated but a few in common with the CF diet. The C10 diet significantly up-regulated the expression of Scgb1a1 and Scnn1 g and down-regulated Tac4, Mcpt2, Fcer1a and Fabp1 by twofold, most of them related to lipid metabolism and immune function. The CF and I diets down-regulated the expression of Serpina10 and Apoa4 by twofold. Similar patterns of expression were found by PCR.ConclusionMost of the effects attributed to cocoa consumption on genes related to the immune system (B cell and mast cell functionality) and lipid metabolism in the colon tissue were due not only to its fiber content, but also to the possible contribution of polyphenols and other compounds.Electronic supplementary materialThe online version of this article (doi:10.1007/s00394-016-1230-0) contains supplementary material, which is available to authorized users.

Association between urinary metabolic profile and the intestinal effects of cocoa in rats

“…These changes, together with the lower urinary excretion of acetone, suggest an alteration in energy metabolism through the modulation of ketogenesis, BCAA metabolism and the TCA cycle. This shift in energy strategy, together with the lower expression of genes involved in lipid metabolism (33) , may contribute to the reduction of body weight in C10-fed rats, reported here and in previous studies (23,26,28) . Changes in NAD + pathway metabolism further support an alteration in energy metabolism.…”

Cocoa ameliorates renal injury in Zucker diabetic fatty rats by preventing oxidative stress, apoptosis and inactivation of autophagy

“…In this line, it has been recently reported that most of the beneficial effects attributed to cocoa are not only due to its fibre content, and polyphenols and other compounds could also be key factors. 52 Thus, epicatechin and procyanidins seem to contribute in the maintenance of renal function and structure during diabetes. 17,33,35,42 In addition, theobromine alone can protect against uric acid crystallization, 53 and in combination with cocoa flavanols enhance their protective vascular effects, 54 which also seem to participate in the preservation of kidneys.…”

Gut Microbiota in a Rat Oral Sensitization Model: Effect of a Cocoa‐Enriched Diet

“…B cells are responsible for the regulation of commensal bacteria producing IgA [ 52 ], so the more relative abundance of Proteobacteria could activate B cells for IgA production, evidencing higher levels of these mucosal antibodies. Previous studies have associated the effect of a 10% cocoa diet on the reduction of IgA with gene expression modifications of several genes involved in the differentiation and maturation of B cells [ 53 , 54 ]. In this sense, IL-6 gene expression is reduced by the cocoa diet [ 53 ], which could reflect a lower IL-6 secretion by dendritic cells, thus partially explaining the possible dendritic cell involvement in that process.…”