Obesity and related metabolic disorders are often characterized by chronic adipose tissue inflammation, driving systemic insulin resistance and general metabolic dysfunction. Free Fatty Acid Receptor 2 (FFA2) has emerged as a potential modulator of adipocyte function, inflammation, and metabolism. To investigate the role of FFA2 expressed in the adipose tissue, we generated adipose-specific FFA2 knockout mice (Adipoq-F2-KO) and assessed metabolic outcomes under standard laboratory chow and high-fat, high-sugar Western diet conditions, with and without dietary fiber supplementation. We found that adipose-specific FFA2 deletion had minimal metabolic consequences under standard dietary conditions but significantly reduced body weight and adiposity when mice were fed a fiber (fructooligosaccharide)-supplemented Western diet. Subsequent fecal analyses and transcriptomic profiling indicated impaired intestinal lipid absorption as the primary driver of reduced adiposity, suggesting disrupted adipose-intestinal communication. Unexpectedly, the lighter Adipoq-F2-KO mice also exhibited heightened adipose inflammation, characterized by increased macrophage infiltration and pro-inflammatory cytokine expression. Furthermore, in vitro loss-of-function experiments in adipocytes revealed that FFA2 knockdown impaired adipocyte maturation, lipid storage, and anti-inflammatory signaling. Additional studies using intestinal epithelial cells exposed to adipocyte-conditioned media implicated adipose-derived signals in driving intestinal dysfunction. Collectively, our findings highlight adipose-specific FFA2 as critical in regulating adipose tissue inflammation, lipid metabolism, and inter-organ communication.
Nnyamah et al. (Fri,) studied this question.