A Cameroon Western Regions high-fat diet (MACAPOS 2) induces visceral obesity in rat

Abstract

The prevalence of obesity increases yearly in the world. The traditional local diet of the Western Regions of Cameroon was suspected to be the main contributor to the high prevalence of obesity in these Regions. This study aimed to evaluate the effects of a Cameroon-comparable fat diet on visceral obesity in rats. Two groups of male Wistar rats were fed for four months with respectively a normal diet (ND) (3400 kcal/kg of food) and a high-fat diet (HFD) containing maize, cassava, palm oil, and sugar (MACAPOS 2): 35 % carbohydrate, 55 % fat and 10 % proteins (4730 kcal/kg of food). Lee index, body weight, food intake, blood and hepatic lipids, body fat, insulin resistance, glucose tolerance, glycemia, serum insulin, leptin, and adiponectin were evaluated. HFD significantly (P < 0.01) increased body weight and decreased food intake. After four months of diet, 88.8 % of HFD rats were obese (Lee index >30 g/cm), and HFD significantly increased visceral and subcutaneous fats compared to ND. HFD increased triglyceride, total cholesterol, Low-density lipoprotein-cholesterol levels, and the atherogenic index, while the high-density lipoprotein-cholesterol level was decreased. The hepatic triglyceride and total cholesterol levels significantly (P < 0.01) increased in HFD, compared to ND. In HFD, the fasting blood glucose, serum insulin, and leptin levels significantly (P < 0.01) increased, meanwhile adiponectin decreased. HFD-induced glucose intolerance and insulin resistance in rats. Based on our findings, we can conclude that HFD MACAPOS 2 can induce central obesity. Therefore, it can be used as a model of diet-induced obesity.

Keywords: Adiponectin; Central obesity; High-fat diet; Insulin; Leptin; MACAPOS 2.

Fig. 1

Food intake (a), Body weight variation or weight gain (b), and Lee index (c) of rats during or after four months of diet. ND: Normal diet, HFD: High-fat diet. n = 5. Each point represents the Mean ± SEM. Significant difference: ∗P < 0.05, ∗∗P < 0.01 compared to ND; ^aP < 0.05, ^bP < 0.01 compared to the initial value.

Fig. 2

Mesenteric (MF), peri-renal (PRF), Peri-testicular (PTF), and subcutaneous (SCF) relative weight fat accumulation (a) expressed as % of rat body weight and Abdomen morphology of normal (b1) and HFD (b2) rats after four months diet. ND: Normal diet, HFD: High-fat diet, MF: Mesenteric fat, SCF: subcutaneous fat, PRF: peri-renal fat, PTF: peri-testicular fat. n = 5. Significant difference: ∗∗P < 0.01 compared to ND. Each column represents the Mean ± SEM.

Fig. 3

Serum lipids (a) and atherogenic index (b) of rats after four months of diet. ND: Normal diet, HFD: High fat diet, TC: Total cholesterol, TG: Triglycerides, HDL-C: HDL-cholesterol, LDL-C: LDL-cholesterol. n = 5. Each column represents the Mean ± SEM. Significant difference: ∗P < 0.05, ∗∗P < 0.01 compared to ND.

Fig. 4

Fasting level of glucose (a), insulin (b), and HOMA-IR index (c) of rats after four months of diet. ND: Normal diet, HFD: High-fat diet. n = 5. Each column represents the Mean ± SEM. Significant difference: ∗P < 0.05, ∗∗P < 0.01 compared to ND.

Fig. 5

Serum levels of leptin (a) and adiponectin (b) of rats after four months of diet. ND: Normal diet, HFD: High-fat diet. n = 5. Each column represents the Mean ± SEM.Significant difference: ∗∗P < 0.01 compared to ND.

Fig. 6

Glucose level (a) and area under the curve (AUC) (b) after the OGTT in rats after four months of diet. ND: Normal diet, HFD: High-fat diet. n = 5. Each point or column represents the Mean ± SEM. Significant difference: ∗∗P < 0.01 compared to the ND, and ^aP < 0.05, ^bP < 0.01 as compared to the initial value.

Fig. 7

Glucose level (a) and area under the curve (AUC) (b) after the ITT in rats after four months of diet. ND: Normal diet, HFD: High-fat diet. n = 5. Each point or column represents the Mean ± SEM. Significant difference: ^bP < 0.01 compared to the initial value and ∗P < 0.05; ∗∗P < 0.01 compared to the ND.

Fig. 8

Hepatic Total cholesterol (TC) and Triglycerides (TG) of rats after four months diet. ND: Normal diet, HFD: High-fat diet. n = 5. Each column represents the Mean ± SEM. Significant difference: ∗∗P < 0.01 compared to ND.