Metabolic syndrome (MetS) is a cluster of cardiovascular risk factors including
central obesity,
hypertension,
insulin resistance,
dyslipidemia, and hyperglyemia. MetS is found to be a positive predictor of cardiovascular morbidity and mortality. The present study was planned to test the efficacy of
vitamin D3 supplementation as compared with
cortisol inhibition on MetS parameters. Wistar rats were allocated into four groups: control, untreated MetS, and MetS treated with either
vitamin D3 (10 µg/kg) or
carbenoxolone (50 mg/kg). MetS was induced by combination of high-fat diet and oral
fructose. After the induction period (8 weeks), MetS was confirmed, and treatment modalities started for a further 4 weeks. Compared with untreated MetS,
vitamin D3- and
carbenoxolone-treated rats showed significant reduction in blood pressure, body mass index, Lee index, waist circumference, retroperitoneal fat, and improvement of
dyslipidemia. Meanwhile, treatment with
carbenoxolone significantly lowered the elevated liver
enzymes, and
vitamin D3 resulted in improved
insulin sensitivity, enhanced
glucose uptake by muscles, and replenished
glycogen content in the liver and muscles near control levels. In conclusion, although treatment with
vitamin D3 or
carbenoxolone reduced the risk factors associated with MetS,
vitamin D3 was effective in ameliorating
insulin resistance which is the hallmark of MetS.