Xanthohumol lowers body weight and fasting plasma glucose in obese male Zucker fa/fa rats

College of Pharmacy, Oregon State University, Corvallis, OR 97331, USA.
Phytochemistry (Impact Factor: 3.35). 05/2012; 91. DOI: 10.1016/j.phytochem.2012.04.018
Source: PubMed

ABSTRACT Obesity contributes to increased risk for several chronic diseases including cardiovascular disease and type 2 diabetes. Xanthohumol, a prenylated flavonoid from hops (Humulus lupulus), was tested for efficacy on biomarkers of metabolic syndrome in 4week old Zucker fa/fa rats, a rodent model of obesity. Rats received daily oral doses of xanthohumol at 0, 1.86, 5.64, and 16.9mg/kg BW for 6weeks. All rats were maintained on a high fat (60% kcal) AIN-93G diet for 3weeks to induce severe obesity followed by a normal AIN-93G (15% kcal fat) diet for the last 3weeks of the study. Weekly food intake and body weight were recorded. Plasma cholesterol, glucose, insulin, triglyceride, and monocyte chemoattractant protein-1 (MCP-1) levels were assessed using commercial assay kits. Plasma and liver tissue levels of XN and its metabolites were determined by liquid-chromatography tandem mass spectrometry. Plasma and liver tissue levels of xanthohumol were similar between low and medium dose groups and significantly (p<0.05) elevated in the highest dose group. There was a dose-dependent effect on body weight and plasma glucose levels. The highest dose group (n=6) had significantly lower plasma glucose levels compared to the control group (n=6) in male but not female rats. There was also a significant decrease in body weight for male rats in the highest dose group (16.9mg/kg BW) compared to rats that received no xanthohumol, which was also not seen for female rats. Plasma cholesterol, insulin, triglycerides, and MCP-1 as well as food intake were not affected by treatment. The findings suggest that xanthohumol has beneficial effects on markers of metabolic syndrome.

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    • "In 3T3-L1 adipocytes, Yang et al. reported reduced lipid content and decreased adipocyte marker proteins after incubation with XN [9]. XN also lowers body weight and fasting plasma glucose in obese male Zucker fa/fa rats [10]. Decreased production of the proinflammatory cytokines IL-1 beta, inducible nitric oxide synthase [11], and IL-12 [12] in LPS-activated macrophages, and reduced monocyte chemoattractant protein 1 (MCP-1) and tumor necrosis factor alpha concentrations were observed after XN treatment in mouse macrophages and human monocytes [13]. "
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