Effect of Ocimum gratissimum and Vernonia amygdalina Leaf Extracts on Carbon Tetrachloride-induced Gastro-intestinal Toxicity in Rats

Abstract

Introduction: Globally, the occurrence of gastrointestinal diseases appears to have increased rapidly and currently accounts for the upsurge in disease burden and household expenditures on healthcare. For example, a 25.82 percent increase in the occurrence of gastric ulcers was reported between 1990 and 2019 and was projected to go higher in the years ahead. Aim: To determine the effect of the extracts of Ocimum gratissimum (OG) and Vernonia amygdalina (VA) on induced gastrointestinal toxicity in male rats Methods: A total of twenty-five (25) adult Wistar rats were used for the study and randomly divided into five groups of five rats each. Group I served as the normal control, Group 2 received CCl₄ only, Group 3 received CCl₄ followed by OG extract, Group 4 received CCl₄ followed by VA extract, while Group 5 received CCl₄ followed by a combined extract of OG and VA. The plant extracts were administered orally at a dosage of 208 mg/kg for OG and 52 mg/kg for VA for the treatment period of two weeks. Results: On mucus weight, Group 5 (OG + VA) combined treatment resulted in a weight of 41.00 \(\pm\) 1.73 which is higher than the positive control. This indicated that VA exhibited the strongest restorative effect on mucus weight (P < 0.05). on pH of the stomach, Treatment groups (Group 3, 4 and 5) showed significantly higher pH values (3.04 \(\pm\) 0.30, 3.04 \(\pm\) 0.25, 3.07 \(\pm\) 0.25) comparable to the negative control group 1 (3.00 \(\pm\) 0.48) at P < 0.05. Also, pepsin activity was highest in the positive control group 2 (23.50 \(\pm\) 0.18) P < 0.05 indicating increased proteolytic activity that could worsen gastric damage. All treatment groups showed significantly lower pepsin activity, similar to the negative control group 1 (20.24 \(\pm\) 0.12) at P < 0.05. Conclusion: oral administration of OG and VA leaf extracts at a dose of 208 mg/kg and 52 mg/kg respectively exhibited protective effects against CCl₄-induced gastrointestinal toxicity in rats, with the combined extract showing enhanced efficacy. These findings suggest the potential therapeutic role of these medicinal plants in managing gastrointestinal toxicity.