Study of the high-fat diet-induced hyperlipidemia and hepatic steatosis in mice

All mice were randomly divided into 5 groups (n = 8–10) and received the following: Group a) Normal-chow diet (Table 1); Groups b to e) High-fat diet (contains 21% fat and 0.15% cholesterol) (Table 2). Diets were given for 8 weeks for animals to induce obesity. After 8 weeks, all high-fat fed groups were given distilled water, or simvastatin daily, and or HCE treatment intragastrically, 3 hours after simvastatin administration. The herbal extract or simvastatin was dissolved in 0.5% methyl cellulose (Sigma-Aldrich Corporation, USA) in distilled water at a known concentration. A pre-calculated volume was intragastrically given to each animal according to the individual’s weight so that the calculated volume contained the amount of proposed dose required. Details of these groups are as follows:

Nutritional information for SF04-057 normal diet as used in the mice study.

Nutritional information for SF00-219 high-fat diet as used in the mice study.

Group a) Normal-chow diet + distilled water

Group b) High-fat diet + distilled water

Group c) High-fat diet + simvastatin (50 mg/kg)

Group d) High-fat diet + HCE (4.4 g/kg)

Group e) High-fat diet + simvastatin (25 mg/kg) + HCE (4.4 g/kg)

Food intake was recorded daily and body weight was measured twice weekly. At the end of the 16-weeks study, all mice were sacrificed after a 16-hour overnight fasting. Animals were anaesthetized by a mixture of ketamine (100 mg/kg) and xylazine (10 mg/kg) intraperitoneally. Blood was withdrawn by cardiac puncture and allowed to clot. Plasma was separated by centrifugation (3,000 rpm for 10 minutes). Livers were excised and stored at −80 °C until analysis.