Aloe vera and garlic ameliorate deleterious consequences of thermoxidized palm oil diet on liver function and histology in rat

Abstract

Purpose A plethora of publications have reported several cytotoxic effects associated with chronic consumption of thermoxidized palm oil. This research aims to investigate the effects of garlic and Aloe vera on liver function and hepatic cytoarchitecture in rats fed thermoxidized palm oil diet. Design/methodology/approach Thirty-five male albino Wistar rats weighing 150-180 g were used for this study. They were randomly assigned into five groups (n = 7): control, thermoxidized palm oil diet fed (TPO), TPO plus garlic juice (TPO + G), TPO plus Aloe gel (TPO + A) and TPO plus garlic/Aloe gel (TPO + G + A). The TPO diet was prepared by mixing 15 g of cooled thermoxidized palm oil with 85 g of rat feed. The juice and gel were orally administered at doses of 2.00 ml/kg and 19.12 ml/kg, respectively. After 3 months of feeding and administration, the animals were sacrificed using standard methods and blood collected via cardiac puncture for analysis. Findings Serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase were significantly increased (p < 0.001) in the TPO group compared to the control. This increase was reduced (p < 0.001) in all the treated groups compared to TPO, with the greatest decrease (p < 0.001) seen in TPO + A. Total bilirubin was increased (p < 0.001) in the TPO group compared to the control, whereas there was a significant decrease (p < 0.001) in all the treated groups. Serum proteins and plasma fibrinogen were lowered (p < 0.001) in the TPO group compared to the control but increased progressively in all the treated groups. TPO induced prominent histopathological derangements of the liver tissues. However, there were marked improvements following treatment with garlic and Aloe vera. Originality/value The results obtained in this study have revealed that chronic consumption of thermoxidized palm oil is hazardous to health by inducing hepatotoxicity, as seen in increased ALT, AST and total and unconjugated bilirubin and decreased total protein. However, these debilitating effects were seen to be greatly ameliorated following garlic juice and Aloe vera gel administration. If these results are to be extrapolated to humans, then the chronic consumption of thermoxidized palm oil diet should be seriously discouraged.