Acute, Sub-acute and Chronic Toxicity Evaluation of Aqueous Extract of the Aerial Parts of Leonurus cardiaca in Normal Non-pregnant Female Wistar Albino Rats per OECD 425 TG

This study graded the acute, sub-acute, and chronic toxicity of aqueous extract of the aerial parts of Leonurus cardiaca in non-pregnant female wistar rats. Fifty wistar albino rats weighing between 180 and 200g were used for this study. The rats were grouped into 10 groups of five rats per group. Group 1 served as control while group 2-11 were orally administered aqueous extract of Leonurus cardiaca at 166, 250, and 500mg/kg for 7, 14, and 21 days. All haematological and biochemical parameters were determined based on standard methods. The plasma RBC, Hb, MCV, and WBC of the control were 5.33±0.01 x 1012/L, 13.54±0.01 g/dl, 42.16±0.01 fl, and 1.83±0.01 X 109/L respectively. The plasma RBC, Hb, MCV, and WBC of the rats treated with 500mg/kg of the extract for 21 days were 10.93±0.01x 1012/L, 19.24±0.01g/dl, 28.33±0.01fl, and 1.41±0.01 x 109/L respectively and were significantly different from the control at p≤0.05. The plasma Na+, K+ , Cl-, HCO3 , creatinine, and urea levels treated with extract at 500mg/kg for 21 days were 167.97±0.01 01mmol/l, 7.85±0.0101mmol/l, 164.24±0.0101mmol/l, 40.84±0.0101mmol/l, 1.16±0.0101mmol/l, and 5.68±0.02 01mmol/l respectively, were significantly different from the control at p≤0.05. The plasma ALT, ALP, and AST activities treated with extract at 500mg/kg for 21 days were 146.24±0.02U/L, 77.33±0.01U/L, and 168.71±0.01U/L respectively, were significantly different from the control at p≤0.05. Enhancement on architecture of the heart, kidney and liver tissues occurred after treatment with 500mg/kg of the extract for 21 days in comparison to the control. The significantly improved effects observed on all assayed parameters were expressive that the extract of the aerial parts of Leonurus cardiaca is safe at 500 mg/Kg.