Abnormal fat accumulation with gut microbiota dysbiosis results in hepatic inflammation by upregulating the release of lipopolysaccharide (LPS) and inflammatory cytokine. Gochujang, a traditional fermented condiment, has beneficial effects, such as anti-colonic inflammatory effects. However, Gochujang has been controversial because of its high salt content (the Korean Paradox). Thus, the present study aimed to investigate the preventative effects of Gochujang on hepatic inflammation and related gut microbiota through discussing the Korean Paradox. The mice were divided into groups including a normal diet (ND), high-fat diet (HD), HD with salt (SALT), HD with a high percentage of beneficial microbiota Gochujang (HBM), and HD with diverse beneficial microbiota Gochujang (DBM). Gochujang markedly reduced lipid accumulation, hepatic injury, and inflammation response. Furthermore, Gochujang attenuated protein expression involved in the JNK/IκB/NF-κB pathway. Additionally, Gochujang regulated the gut microbiota-derived LPS production and Firmicutes/Bacteroidetes ratio. Gochujang regulated the levels of gut microbiota such as Bacteroides, Muribaculum, Lactobacillus, and Enterorhabdus, which were correlated with hepatic inflammation. Salt did not have foregoing effects, meaning that the salt content in Gochujang did not affect its anti-inflammatory effect. In conclusion, Gochujang showed anti-hepatic inflammation effects via reduced lipid accumulation, hepatic injury, and inflammatory response together with reorganization of gut microbiota dysbiosis regardless of salt content and the difference of micro bacteria composition.

Hyperlipidemia, characterized by elevated cholesterol, lipids, and triglycerides in the bloodstream, is linked to hepatic oxidative damage. Doenjang, a traditional Korean condiment made from fermented soybeans, is known for its health benefits, yet its anti-hyperlipidemic effects remain understudied. Our study aimed to assess the hypolipidemic and hepatic protective effects of Doenjang on male ICR mice fed a high-fat cholesterol diet for 8 weeks. Mice were divided into three groups: the normal diet (ND), the high-fat cholesterol diet (HD), and the Doenjang-supplemented HD diet (DS) group. Doenjang supplementation significantly regulated total cholesterol, triglycerides, LDL cholesterol, and HDL cholesterol levels compared to the HD group. It also downregulated lipogenic genes, including PPARγ, FAS, and ACC, and positively influenced the cholesterol metabolism-related genes HMGCR and LXR. Moreover, Doenjang intake increased serum glutathione levels, activated oxidative stress defense genes (NRF2, SOD, GPx1, and CAT), positively modulated inflammation genes (NF-kB and IL6) in hepatic tissue, and reduced malondialdehyde levels. Our findings highlight the effectiveness of traditional Doenjang in preventing diet-induced hyperlipidemia and protecting against hepatic oxidative damage.

High-fat and high-salt diets are risk factors for metabolic syndrome development. However, gochujang, which has a high salt content, possesses antiobesity properties in cell and animal models. We aimed to evaluate the effects of Sunchang traditional and modern factory produced gochujang on metabolic syndrome factors in high-fat diet (HFD)-induced obese mice. For 14 weeks, 4-week-old C57BL/6J male mice were separated into five groups and fed a normal diet (ND), a high-fat diet only (HD), a HD with salt (SALT), a HD with traditional Sunchang gochujang (TS), and HD with modern factory made Sunchang gochujang (FS). Compared to HD and SALT groups, the gochujang groups had lower body weight, blood leptin, and insulin levels with reduced Homeostatic Model Assessment of Insulin Resistance (HOMA-IR) index and improved serum and liver lipid profiles. In addition, gochujang supplemented groups exhibited a significant reduction in mRNA expression of anabolic lipid metabolism related factors; PPARγ , CEBPα , and FABP4 , and a significant increase in mRNA expression of energy expenditure-related factors; PPARα and CPT1 . Protein expressions of SREBP1 were downregulated in the gochujang fed groups. TS and FS intakes improved obesity in HFD-induced obese mice. Compared to the gochujang groups, the SALT group did not exhibit any of those benefits suggesting that the high salt content of gochujang has different effects compared with added salt alone. Our findings provide evidence that gochujang could be a functional food to attenuate metabolic syndrome.

Edward OC, et al. Nutr Res Pract. 2022 Oct;16(5):549-564. https://doi.org/10.4162/nrp.2022.16.5.549