Anti-obesity effects of kimchi added with Jeju citrus concentrate on high-fat diet induced obese mice: Anti-obesity effect of CK in obese mice

Abstract Citrus fruits contain an abundance of nutrients, including vitamin C, B6, and hesperidin, which attribute to its beneficial health effects. Previously, kimchi with Jeju citrus concentrate (CK) elicited anti-obesity effects in 3T3-L1 adipocytes. Here, we aimed to investigate whether CK exhibits anti-obesity effects by reducing serum and hepatic lipid concentrations and anti-obesity-associated gene expression in high-fat diet (HFD)-induced obese C57BL/6N mice. Low-dose CK (LDCK, 50 mg/kg) and high-dose CK (HDCK, 200 mg/kg) were orally administered three times per week over 8 weeks with HFD diet. Body weight gain, food efficiency ratio (FER), and tissue weight were measured. Serum glutamic oxaloacetic transaminase (GOT), glutamic pyruvic transaminase (GPT), fasting glucose, fasting insulin, homeostatic model assessment-insulin resistance (HOMA-IR), leptin, and adiponectin levels were also measured. The effect of CK on the lipid profile and lipid accumulation was analyzed. Body and white adipose tissue (WAT) weights were significantly lower in the LDCK and HDCK groups than in the HFD group. Orally administered CK significantly decreased serum lipid, fasting glucose, fasting insulin, HOMA-IR, GOT, and GPT levels. Hepatic lipid content also decreased in the LDCK and HDCK groups. Serum leptin levels decreased, whereas serum adiponectin levels increased, confirming the anti-obesity effects of LDCK and HDCK. The decrease of hepatic vacuoles and stained lipid droplets indicated inhibition of lipid accumulation. These results support the hypothesis that CK exhibits anti-obesity effects in vivo by reducing lipid level and accumulation and by regulating anti-obesity-related genes.