Antidiabetic properties of Tarchonanthus camphoratus in fructose-induced diabetic Wistar rats

Tarchonantus camphoratus (TC) has been used traditionally to manage diabetes mellitus (DM) in Kenya but its efficacy has not been scientifically evaluated. This study aimed at evaluating the antidiabetic properties of TC crude leaf extract in diet-induced diabetic Wistar rats. DM was induced using high fructose (25% w/v) in drinking water for 12 weeks. Rats were divided into five groups (n=7): Groups I: normal control; II; diabetic untreated; III, IV & V; diabetic treated (21 days) with metformin (100 mg/kg.bw/day), 300 and 600 mg/kg.bw/day of TC extract respectively. Fasting body weights and blood glucose levels were monitored weekly. Oral glucose tolerance test, serum lipid profile, creatinine, urea, alkaline phosphatase (ALP), aspartate aminotransferase (AST), alanine aminotransferase (ALT), total proteins (TP), C-reactive protein (CRP), albumin (ALB) and triglyceride (TG) mass in skeletal muscle were analysed at end of the study. Qualitative phytochemical analysis was done using standard procedures. Diabetic untreated rats had significantly higher body weights (p ˂0.05) compared to other groups. There was a significant reduction in fasting blood glucose in TC treatment groups compared to untreated controls. Increased glucose tolerance was observed in treated groups. TC extract significantly improved fructose-induced hypertriglyceridemia compared to DM groups. ALP, ALT, and CRP were significantly lowered while TP and ALB were elevated in the extract treated rats compared with untreated DM rats. DM group also exhibited significantly higher skeletal muscle TG mass when compared to normal control and diabetic treated groups. The phytochemical-rich TC leaf extract therefore possess potential alternative medicine for DM management.