Influência da suplementação com cumarina (4-metildinafetina) e atividade física voluntária sobre o browning do tecido adiposo branco em camundongos

Abstract

Browning is known as the ability of white adipose tissue (WAT) to present a phenotype similar to brown fat when stimulated, leading to an increase in thermogenesis. The study aims to verify whether supplementation with coumarin (4-methyldinafetine) in association with voluntary physical activity, has the effect of inducing browning in the adipose tissue of mice and analyzing the presence of hepatic steatosis. 32 male mice (C57BL6) were used, with about 8 weeks, kept in light / dark cycle of 12-12 hours, in cages with or without free activity wheels. The animals were acclimatized for a period of 7 days and immediately afterwards, the animals were separated into four groups (n: 8): voluntary physical activity with coumarin administration (AFC), voluntary physical activity vehicle (AFV), sedentary with coumarin administration (SC) and sedentary vehicle (SV). The animals received a concentration of 30 mg / kg / animal of 4- Methyldaphenethine for the AFC and SC groups, and 0.9% saline; Carboxylmethylcellulose (CMC) 0.3%; and Tween 1% with the same dose for the AFV and SV groups for 28 days, via gavage. At the end of the experiment the animals were euthanized and the liver and adipose tissues were extracted and stored in the inguinal, epididymal and interscapular regions. Subsequently, running time and histological analyzes were performed with hematoxylin and eosin and periodic acid-schiff staining. To verify data normality and homogeneity of variances, the Shapiro-Wilk and Levene tests were used. For comparisons between groups, one-way and two-way ANOVA tests and Student's t test for independent samples were adopted. For all data, a significance level of p<0,05 was adopted. We did not obtain any significant differences between the number of laps. For the inguinal adipose tissue in both the sedentary group and the physical activity group, the animals that received 4-methyldinephetine had a larger area, the same happened for the epididymal adipose tissue with the difference that physical activity had a protective effect in relation to 4 -methyldinefetine. It was concluded that coumarin 4- methyldinefetine did not generate browning, did not alter the volume of voluntary physical activity and did not cause hepatic steatosis. However, with the exception of the AFC group of epididymal adipose tissue, ingestion of this coumarin for 4 weeks causes an increase in adipocyte in the epididymal and inguinal white adipose tissue of C57BL / 6 mice.