Inhibition of the CD36 receptor reduces visceral fat accumulation and improves insulin resistance in obese mice carrying the BDNF-Val66Met variant

摘要

Obesity-induced metabolic dysfunctions increase the risk for vascular diseases, including type II diabetes and stroke. Managing obesity is of interest to address the worldwide health problem; however, the role of genetic variability in human obesity development and specific targets for obesity-related metabolic disease have not been thoroughly studied. A SNP in the brain-derived neurotropic factor (BDNF) gene that results in the substitution of a valine with a methionine at codon 66 (Val66Met) occurs with a high frequency in humans. This study addressed the effect of genetic variability in developing obesity and the efficacy of the inhibition of cluster of differentiation 36 (CD36), a multifunctional receptor implicated in obesity and insulin resistance, in WT mice and mice with the BDNF Val66Met variant. CD36 inhibition by salvionolic acid B (SAB) in diet-induced obese WT mice reduced visceral fat accumulation and improved insulin resistance. The benefit of SAB was abrogated in CD36 knockout mice, showing the specificity of SAB. In addition, mice with the Val66Met variant in both alleles (BDNF^M/M) fed a high-fat diet exhibited extreme obesity with increased CD36 gene and protein levels in macrophages. Chronic SAB treatment in BDNF^M/M mice significantly decreased visceral fat accumulation and improved insulin resistance. Notably, the effect of SAB was greater in the extremely obese BDNF^M/M mice compared with the WT mice. The study demonstrated a link between BDNF Val66Met and elevated CD36 expression and suggested that CD36 inhibition may be a potential strategy to improve metabolic dysfunctions and to normalize risk factors for vascular diseases in the obese population.