Effects of Black Adzuki Bean (Vigna angularis) Extract on Proliferation and Differentiation of 3T3-L1 Preadipocytes into Mature Adipocytes

Abstract

The aim of this work was to investigate the effects of black adzuki bean (BAB) extract on adipocytes, and to elucidate the cellular mechanisms. In order to examine the proliferation of preadipocytes and differentiating adipocytes, cell viability and DNA content were measured over a period of time. Lipid accumulation during cell differentiation and the molecular mechanisms underlying the effects of BAB on the transcriptional factors involved, with their anti-adipogenic effects, were also identified. We observed that BAB exhibits anti-adipogenic effects through the inhibition of proliferation, thereby lowering mRNA expression of C/EBPβ and suppressing adipogenesis during the early stage of differentiation. This, in turn, resulted in a reduction of TG accumulation in a dose- and time-dependent manner. Treating the cells with BAB not only suppressed the adipogenesis-associated key transcription factors PPARγ and C/EBPα but also significantly decreased the mRNA expression of GLUT4, FABP4, LPL and adiponectin. The expression of lipolytic genes like ATGL and HSL were higher in the treatment group than in the control. Overall, the black adzuki bean extract demonstrated an anti-adipogenic property, which makes it a potential dietary supplement for attenuation of obesity.

Antiobesity Effects of Purple Perilla (Perilla frutescens var. acuta) on Adipocyte Differentiation and Mice Fed a High‐fat Diet

“…Hypertrophy and hyperplasia lead to adipose tissue expansion, and hypertrophy occurs before hyperplasia in the progression of obesity (de Ferranti & Mozaffarian, ; Jo et al., ). The process where preadipocytes differentiate into lipid‐laden adipocytes is called adipogenesis, occurs in several stages, including preadipocyte cell proliferation, differentiation and lipid accumulation and transcription factors such as peroxisome proliferator activated receptor gamma (PPARγ) and CCAAT/enhancer binding proteins (C/EBPs) regulates this process (K. N. Kim et al., ; M. Kim, Park, Song, & Cha, ). Lipogenesis is the process of triglyceride (TG) synthesis, which requires enzymes including acetyl CoA carboxylase (ACC) and fatty acid synthase (FAS) (Sung et al., ).…”

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

“…BAB has previously been shown to inhibit lipid accumulation in adipocyte cells downregulating C/EBPβ , C/EBP α, and PPARγ expression (Kim et al ). Another study reported that adzuki beans stimulate phosphorylation of AMP activated protein kinase (AMPK), which may suppress ACC (Sato, Mukai, Kataoka, & Kurasaki ).…”

“…The BAB extract was freeze‐dried and ground into a powder. The composition of freeze‐dried BAB powder samples has been previously characterized (Kim et al ).…”

“…In addition to this advantage, the BAB has certain variety‐specific characteristics, such as its lodging tolerance, that give it additional advantages in mechanized operations at harvest time (Song ). In a previous study, BAB treatment was shown to inhibit preadipocyte proliferation and to suppress differentiation into mature adipocytes (Kim et al ). These results have stimulated investigations into the potential anti‐obesity effects of BAB in vivo.…”

“…So far, most studies have been carried out on red adzuki beans. However, this work was focused on the black adzuki bean (BAB), which has been shown to have high levels of polyphenols and to possess relatively high antioxidant activity compared to other adzuki bean varieties (Kim, Park, Song, & Cha ; Song ). In addition to this advantage, the BAB has certain variety‐specific characteristics, such as its lodging tolerance, that give it additional advantages in mechanized operations at harvest time (Song ).…”