Efeito de um iogurte de soja suplementado com isoflavonas e com propriedades probióticas sobre o perfil lipídico e adiposidade em ratos jovens alimentados com dieta hipercolesterolêmica

Abstract

This study investigated the effects of soy yogurt fermented by Enterococcus faecium CRL 183 and Lactobacillus jugurti 416 supplemented with isoflavones on adipose tissue, blood lipid, and glucose levels on juvenile rats. Male Wistar rats were then randomly divided into groups: chow diet (C), cholesterol-enriched diet (H), cholesterol-enriched diet/chow diet (HC), cholesterol-enriched diet/chow diet plus soy yogurt supplemented with isoflavones (HCYI), cholesterol-enriched diet/chow diet plus placebo (HCP), cholesterol-enriched diet/chow diet plus placebo supplemented with isoflavones (HCPI), cholesterol-enriched diet plus soy yogurt supplemented with isoflavones (H+YI), cholesterol-enriched diet plus placebo (H+P), and cholesterol-enriched diet plus placebo supplemented with isoflavones (H+PI). C and H groups were fed for 6 weeks on a chow diet or a cholesterol-enriched diet, respectively. Rats in the HC, HCYI, HCP, and HCPI groups were fed a cholesterol-enriched diet for 3 weeks as a preliminary treatment to create hypercholesterolemia. Rats were then given the chow diet or the chow diet plus soy products for additional 3 weeks. Additionally, animals in the H+YI, H+P, and H+PI groups were fed for 6 weeks on a cholesterol-enriched diet plus soy products. The soy products (yogurt supplemented with isoflavones, placebo, and placebo supplemented with isoflavones) were fed to each animal at the rate of 1ml/day. Food and water were consumed ad libitum. The beneficial effects of soy yogurt on epididymal (EPI) and retroperitoneal (RET) fat pads was likely due to isoflavones because adipocyte circumference (micrometers) in the HCP group was significantly larger (EPI: 105.66 ± 13.36; RET: 134.95 ± 25.40) than that in the HCYI group (EPI: 93.17 ± 12.80; RET: 108.62 ± 15.50) and HCPI group (EPI: 93.06 ± 15.10; RET: 112.34 ± 18.21). The probiotic micro-organism accentuated the antilipogenic effect of isoflavones on RET (HCYI: 108.62 ± 15.50 micrometers versus HCPI: 112.34 ± 18.21 micrometers). Moreover, the soy yogurt increased glucose concentration similar to that in the chow group but did not change blood lipids. On the other hand, soy supplementations with cholesterol-enriched diet exhibited regional variations in fat pads. It may be responsible for the increased observed on retroperitoneal adipocyte circumference (micrometers) (H+YI: 122.31 ± 1.39; H+P: 124.48 ± 1.53, or H+PI: 124.85 ± 1.09 versus C: 99.68 ± 1.49 or H: 103.26 ± 0.76) or decreased of epididymal adipocyte circumference (micrometers) (H+YI: 96.42 ± 0.68, and H+PI: 94.87 ± 0.69) compared with the C group (99.47 ± 0.95). In the same way, effect on epididymal adipose tissue was likely due to isoflavones. Probiotics do not seem to enhance the effect of isoflavones, but improved HDL cholesterol plasma levels. Soy yogurt supplemented with isoflavones did not promote changes on plasma triacylglycerol, but increased glucose concentration. If these results are confirmed in further studies, they will offer new approaches to obesity prevention or lipid metabolism abnormalities.