Extract of the Microalga Nitzschia laevis Prevents High-Fat-Diet Induced Obesity in Mice by Modulating the Composition of Gut Microbiota.

SCOPE: The aim of the present study was to investigate the efficacy of Nitzschia laevis extract (NLE) in preventing obesity in mice fed with a high-fat-diet (HFD), and the potential underlying mechanisms focusing on modulation of gut microbiota profile.

METHODS AND RESULTS: Physiological, histological and biochemical parameters and gut microbiota compositions were compared among four experimental groups fed respectively with the following diets for 8 weeks: Normal chow diet, HFD, HFD + low concentration of NLE and HFD + high concentration of NLE. The results demonstrated that NLE supplementation significantly reduced body weight gain and effectively prevented lipid accumulation in the white adipose tissue and liver of the mice. Mechanistic analysis revealed that NLE promoted the expression of uncoupling protein 1 and peroxisome proliferators-activated receptor-γ coactivator-1 mRNA in brown adipose tissue. Furthermore, NLE protected the gut epithelium and positively reshaped the gut microbiota composition against the damaging effect of HFD.

CONCLUSIONS: NLE supplementation demonstrated a protective effect against HFD-induced obesity in mice, which was associated with reshaping the profile of gut microbiota. To the best of our knowledge, this has been the first report on the potential of microalgal extract to prevent obesity by modulating gut microbiota. This article is protected by copyright. All rights reserved.