Traditional Sunchang Gochujang Attenuates Obesity in High-Fat Diet Induced Obese Mice

Abstract Objectives Obesity is a major global health crisis. High fat diet (HFD) and salt intake have been linked to leptin resistance and obesity. Korea has lower obesity prevalence relative to other countries, although Koreans consume various fermented substances containing high salt, such as gochujang and doenjang amongst others. This phenomenon is defined as “the Korean paradox”. Gochujang is a Korean fermented pepper paste that contains high amount of salt. Therefore, we aimed to evaluate the anti-obesity potential of traditional gochujang on HFD-induced obese mice by comparing its effects with HFD and HFD containing same amount of salt from traditional gochujang. Methods 4 weeks old C57BL/6J male mice were divided into 4 groups and fed a normal diet (ND), HFD (HD), HFD + salt (SALT) and HFD + traditional sunchang gochujang (TS) diets for 14 weeks. Biochemical analyses of serum, liver, and brown and epididymal fat tissues were performed to assess metabolic changes and obesity-related markers. The expressions of mRNA and protein involved in obesity, lipogenesis, adipogenesis and energy expenditure were evaluated from liver, brown and epididymal fat tissues by qPCR and western blot. Results TS supplementation significantly reduced obesity in HFD-induced obese mice. Compared to HD, TS had a lower body weight (24%), reduced serum leptin and insulin levels and improved serum and liver lipid profiles. Compared to HD and SALT groups, TS group had a significant reduction of mRNA and protein expressions associated with anabolic lipid metabolism including leptin, PPARγ, CEBPα, FAS, and ACC, while showing significant increase of adiponectin and energy expenditure-related mRNA, such as PPARα and CPT1. Conclusions TS ameliorates obesity in HFD-induced obese mice by boosting leptin levels and inhibiting the adipogenesis and lipogenesis. Also, SALT group did not show any improvements compared with TS group. These observations imply that high salt content of TS is not a problematic feature. Our findings prove “the Korean paradox” of gochujang and anti-obesity effects of traditional gochujang, proposing the possibility of the traditional gochujang as a functional food against obesity. Funding Sources Ministry of Agriculture, Food and Rural Affairs and partly Korea Agro-Fisheries and Food trade corporation.