Ninety Days Repeated Sub-Chronic Toxicity Study of Ethanol Leaf Extract of Laggera Aurita Linn (Asteracea) In Wistar Rats

Laggera aurita Linn (Asteraceae) is widely used in Nigeria, Cameroon, Ghana, Senegal, and India for treating malaria, cancer, epilepsy, tuberculosis, and rheumatoid arthritis. This study seeks to establish the safety profile of the ethanol extract of Laggera aurita (EELA). An acute toxicity limit test at 5000 mg/kg was conducted as per OECD 425 and determined to be > 5000 mg/kg. A 90-day oral chronic toxicity study followed, according to OECD 408, involving five groups of ten rats administered the extract at 75, 150, 300, and 600 mg/kg daily, while the control group received 1 ml/kg distilled water. Daily measurements included food and water intake, and body weights were measured weekly. The animals were humanely killed on day 91, and blood samples and vital organs were collected for assays and histopathology. Results indicated no changes in food intake, water intake, body weights, relative organ weights, haematological indices, or reproductive hormones. No elevations of liver transaminase enzymes, bilirubin, or total protein were observed, nor changes in serum creatinine, blood urea nitrogen, or electrolytes. However, a significant (p<0.05) reduction in aspartate transaminase (AST) and urea was observed in the liver and kidney at doses of 150-600 mg/kg compared to control. Additionally, there was a significant (p<0.05) reduction in thyroid hormones and an elevation of cholesterol and low-density lipoproteins at doses of 150-600 mg/kg. The study suggests EELA is generally safe at low doses (75 mg/kg), with the no observed adverse effect level (NOAEL) determined to be 75 mg/kg.