Characterization of Ginger Polysaccharide and Amelioration of High-Fat-Induced Obesity by Regulating the Energy Intake and Expenditure

Ginger polysaccharide (GP) was obtained with a yield of 5.18%, and its main fraction GP-F1 (Mw = 109.24 kDa) was purified for structural characterization. Integrated analysis of monosaccharide composition, methylation pattern, and nuclear magnetic resonance spectra indicated potential structure configurations of arabinoxylan and arabinogalactan. The amelioration effect on obesity of the GP was evaluated in high-fat diet-induced obese mice. After 8 weeks of supplementation, the GP (500 mg/kg) significantly regulated the body weight gain, white adipose tissue (WAT) expansion, abnormal glucose homeostasis, and hyperlipidemia status of obese mice. Notably, GP treatment reduced food intake, normalizing energy consumption to levels comparable to those of control groups. This correlated with decreased leptin concentrations in serum and WAT, indicating amelioration of leptin resistance, which related to appetite regulation. The expression of suppressor of cytokine signaling 3 in the hypothalamus was downregulated, thereby benefiting the JAK-STAT signaling pathway and leptin sensitivity. In addition, GP activated thermogenic pathways in brown adipose tissue, evidenced by upregulated expression of UCP1, PGC-1α, and PRDM16, thereby enhancing energy expenditure. Collectively, GP supplementation alleviated HFD-induced obesity by appetite suppression and energy expenditure promotion.