Ameliorative effect of fermentable fibres on adiposity and insulin resistance in C57BL/6 mice fed a high-fat and sucrose diet
The consumption of diets rich in fat and refined sugars is recognized to be one of the causes of lifestyle disorders, and dietary fibres are being advocated to ameliorate the complications associated with these disorders. In the present study, the effects of two soluble fermentable fibres, viz., gum acacia and inulin on the progression of adiposity, insulin resistance, and the expression of genes related to metabolism were examined in C57BL/6 mice fed a high-fat and sucrose diet for 18 weeks. The feeding of either type of fibre resulted in decrease in body weight, epididymal fat mass, adipocyte size, hyperlipidaemia, hyperglycaemia and hyperinsulinemia. In the fibre-fed groups, the expressions of adiponectin and glucose transporter 4 in the epididymal fat increased significantly, while the expressions of leptin, interleukin 6 and tumor necrosis factor alpha decreased significantly. Moreover, the expressions of genes related to beta-oxidation, viz., carnitine palmitoyltransferase 1, peroxisome proliferator-activated receptor gamma co-activator 1β, and peroxisome proliferator-activated receptor alpha in the liver tissue of the fibre-fed groups enhanced significantly. Furthermore, due to the feeding of either type of fibre, the expressions of zonula occludens 1 and fasting-induced adipose factor in the distal ileum and proglucagon in the colon increased significantly. From the results of the present study, it can be concluded that the beneficial effects of the fibres are mediated due to enhanced energy expenditure, improved intestinal integrity, and reduced inflammation.