Effects of Prolonged Administration of High Fat Diet on Serum Biochemical, Haematological and Organ Histology in Rats

Background: Numerous health challenges have been associated with lipid peroxidation andoxidative damage due to increased consumption of fatty diets.

Aim: This study evaluated serum biochemical and haematological parameters, tissue antioxidant activities and histopathological changes in wistar rats administered high fat diet.

Methods: Forty rats of both sexes weighing 120-150g and assigned to 4 groups of 10 rats each were used. Groups 1 and 2 served as female and male controls respectively, while groups 3 was the female test group which received high fat diet. Group 4 was the male test group which also received high fat diet. Treatment lasted 16 weeks before animals were sacrificed to collect blood and tissue samples for serum biochemical analyses including liver function, renal function and antioxidants tests. Slides of liver and kidney samples were also prepared for histopathological examination.

Results: When compared with control results obtained in the high fat treated rats showed significant increase in body weight gain (p<0.05), increased lipid peroxidation activity (MDA), significant decrease in activities of tissue antioxidant enzymes like glutathione transferase (GST), glutathione peroxidase (GPx), catalase (CAT) andsuperoxide dismutase (SOD), PON 1 and reduced glutathione (GSH) concentration with higher PCO values (p<0.05). Liver function parameters including aspartate aminotransferase(AST), alanine aminotransferase(ALT), alkaline phosphatase (ALP), total protein and bilirubin had higher values in the high fat treated rats than control. Total cholesterol, triglycerides, low density lipoprotein cholesterol and very low density lipoprotein concentrations were also higher in the high fat treated groups but values of high density lipoprotein cholesterol did was not significantly altered following treatment (p>0.05). Haematological parameters like number of red blood cells, packed cell volume and haemoglobin concentration, all significantly reduced in the high fat groups (p<0.05), but number of white blood cells increased significantly. Histopathological examination of liver tissues showed areas with fibrosis, steanosis and lobular inflammations in the high fat groups.

Conclusion: Increased lipid peroxidation and decline in antioxidant defense may account for higher cardiovascular disease risks and its associated complications commonly seen among high fat consumers.