Black adzuki bean (Vigna angularis) extract exerts phenotypic effects on white adipose tissue and reverses liver steatosis in diet-induced obese mice

Abstract

The primary objective of this study was to examine the extent to which black adzuki bean (BAB) extract attenuates the development of high-fat diet-induced obesity in mice. Four-week-old C57BL/6J mice were fed one of the following diets for 12 weeks: control diet containing 10% of its energy as fat (CD); high-fat diet, containing 60% of its energy as fat (HD); high-fat diet mixed with 1% freeze-dried BAB extract powder (BAB); or high-fat diet mixed with 0.08% kaempferol (Kfr). Compared to the HD group, the BAB group showed significantly reduced body weight, reduced white adipose tissue weight, and a reduced adipocyte phenotype. Moreover, the BAB group exhibited decreased signs of liver pathology, decreased liver weight, and decreased formation of hepatic lipid droplets. Lipogenesis-associated genes were significantly downregulated in epididymal fat tissue, while lipolytic and β-oxidation genes were upregulated in the BAB group relative to the HD group. Overall, BAB extract is a promising dietary supplement with the potential to attenuate obesity. Practical applications The adzuki bean has been traditionally consumed as a food and has been used as a traditional remedy in East Asia. Moreover, black adzuki beans have been shown to exhibit beneficial effects, such as anti-obesity and anti-steatosis effects, by regulating lipid metabolism.