Tartary Buckwheat Extract Attenuated the Obesity-Induced Inflammation and Increased Muscle PGC-1a/SIRT1 Expression in High Fat Diet-Induced Obese Rats

Abstract

Obesity is intimately related to a chronic inflammatory state, with augmentation of macrophage infiltration and pro-inflammatory cytokine secretion in white adipose tissue (WAT) and mitochondrial dysfunction in skeletal muscle. The specific aim of this study is to evaluate effects of tartary buckwheat extract (TB) on obesity-induced adipose tissue inflammation and muscle peroxisome proliferator-activated receptor-gamma coactivator (PGC)-1 alpha/sirtulin 1 (SIRT1) pathway in rats fed a high-fat diet. Sprague-Dawley rats were divided into four groups and fed either a normal diet (NOR), 45% high-fat diet (HF), HF + low dose of TB (TB-L; 5 g/kg diet), or HF + high dose of TB (TB-H; 10 g/kg diet) for 13 weeks. TB significantly reduced adipose tissue mass with decreased adipogenic gene expression of PPAR-gamma and aP2. Serum nitric oxide levels and adipose tissue macrophage M1 polarization gene markers, such as iNOS, CD11c, and Arg1, and pro-inflammatory gene expression, including TNF-alpha, IL-6, and MCP-1, were remarkably downregulated in the TB-L and TB-H groups. Moreover, TB supplementation increased gene expression of PGC-1 alpha and SIRT1, involved in muscle biogenesis and function. These results suggested that TB might attenuate obesity-induced inflammation and mitochondrial dysfunction by modulating adipose tissue inflammation and the muscle PGC-1 alpha/SIRT1 pathway.