Antilipogenic Effect of Cirsium japonicum var. maackii According to Harvest Time and Plant Part in High-Fat Diet-Induced Nonalcoholic Fatty Liver Disease

Abstract

The global rise in obesity has been closely linked to an increasing incidence of nonalcoholic fatty liver disease (NAFLD), a major metabolic disorder. In this study, we evaluated the lipid-lowering and hepatoprotective effects of Cirsium japonicum var. maackii (CJ) harvested at different times, spring (CJ-sp), fall (CJ-fall), and from pappus (CJ-pap), a tuft of bristles in CJ, in a high-fat diet (HFD) mouse model. Male C57BL/6 mice were assigned to either a normal control diet (NOR) or HFD, with treatment groups receiving CJ-sp, CJ-fall, CJ-pap (100 and 200 mg/kg), cirsimaritin (Cirsi, 25 mg/kg), or milk thistle (MT, 100 mg/kg). Administration of the CJ extract markedly reduced body weight gain, food efficiency ratio (FER), and serum lipid parameters compared with the HFD control (CTL). Among the extracts, CJ-sp and CJ-pap most effectively alleviated hepatic steatosis, as evidenced by decreased fat deposition and reduced inflammatory changes in liver tissue. In addition, CJ-treated mice displayed significantly lower white adipose tissue mass and smaller adipocyte size than CTL mice. These improvements were associated with the downregulation of hepatic lipogenic genes and activation of fatty acid oxidation pathways. Collectively, CJ supplementation improved metabolic homeostasis and protected against HFD-induced obesity and liver dysfunction. Notably, CJ-sp and CJ-pap exerted greater efficacy than other CJ fractions or MT, suggesting their potential application as functional food ingredients for the prevention of NAFLD.