Efeitos da inulina no metabolismo de camundongos

Abstract

Introduction: Changes in the society’s lifestyle, especially the increase in the consumption of ultra-processed foods, the high intake of red meat, sugar and salt and the scarcity of dietary fibers have implications for the gut microbiota with increasing incidence of adiposity and chronic inflammatory diseases. Dietary fiber are non-digestible forms of carbohydrates and polysaccharides that originate from plant-based foods. Among fibers inulin has been widely studied with emphasis in the area of weight regulation and improvement of metabolic parameters, and linked to positive effects on the host lipid metabolism providing improvements in lipid homeotase, reduction of serum cholesterol and triglyceride rates, reduction of lipogenesis with positive impacts on satiety and body weight. Objectives: To investigate the effects of prebiotic inulin supplementation on the metabolism of mice. Methods: Male Swiss mice were fed for 4 weeks with 2 different isocaloric diets: Standard (ST), Standard + Inulin (ST+I, 10%). Measurements of some parameters, e.g. food/energy intake, body composition data, insulin sensitivity and glucose tolerance. Epidimal adipose, retroperitoneal, mesenteric, subcutaneous and brown tissues, in addition to the liver, muscle, stomach, large and small intestine were weighed; among them, liver, epididimal adipose tissue, muscle, stomach, and the large and small intestines were stored at -80 ˚C for further molecular analysis. In addition, analyses were undertaken for the evaluation of the following parameters total cholesterol (TC), high density lipoprotein (HDL), triglycerides (TG), alanine transaminases (ALT/GPT) and aspartate transfer (AST/GOT) using enzyme kits (Wiener Laboratories, Rosario, Argentina), histology and mRNA expression of epididymal adipose tissue were analyzed. Results: The dietary supplementation of inulin was benefic as it increased HDL biochemical indices, decreased GPT enzymes related to the risk of liver injury, improved the glycemic profile and increased insulin sensitivity. It also reduced the expression of the Toll-like receptor 4 transmembrane protein (TLR4) and interleukin 6 (IL6) in the evaluation of the gene expression of beige adipocytes markers (Pgc1α, Ucp1, Cidea). There was also a trend in the increase in these genes of the treated group compared to the control regarding epididymal adipose tissue, and a decreased hypertrophy of adipocytes with a predominance of small adipocytes while small adipocytes are related to a decreased risk of disorders in metabolism . In hypertrophic adipocytes, there was an increased secretion of inflammatory cytokines and decreased secretion of anti-inflammatory adipocins. Conclusion: Inulin supplementation may improve rates related to the onset of obesity as inflammation prevents extracellular matrix dysfunction (ECM) that induce changes in adipose tissue functionality and variations in its adipokine secretion profile indicating inulin as a natural anti-obesity alternative.