Preliminary Toxicity Studies of Methanol Stem Bark Extract of Lannea acida A. Rich (Anacardiaceae) in Wistar Rats

Abstract

Background: Despite the use of Lannea acida A. Rich for the treatment of many ailments, its safety profile has not been well-elucidated. We aim to determine the acute and subacute oral toxicity of methanol extract of stem bark of L. acida on Wistar rats. Materials and methods: For acute toxicity test, adult female Wistar rats (n = 5) received a single oral dose of 3000 mg/kg of methanol extract of stem back of L. acida by gavage at interval of 48 hours, and were observed for general behavior, adverse effects and mortality for 14 days. For subacute toxicity, 24 adult Wistar rats were divided into four groups (n = 6/group; male = female, 1:1). Group one received distilled water at th 10 ml/kg body weight while groups two, three and four received 250, 500 and 1000 mg/kg body weight of extract orally for 28 days. On the 29 day, rats were euthanized and morphological, biochemical, and hematological parameters determined. Results: Acute oral dose of 3000 mg/kg body weight did not produce any sign of toxicity or mortality in Wistar rats. Subacute treatment showed a decrease in the relative organ weight percent of the kidney at a dose of 1000 mg/kg body weight (P < 0.05); a decrease in the serum potassium across all the doses (P < 0.05), and a rise in serum alanine transaminase at 500 mg/kg (P < 0.05). Histology showed varying degrees of hepatic sinusoidal vascular congestion, peri-portal inflammation; as well as tubulointerstitial inflammation and glomerular necrosis at doses of 250, 500 and 1000 mg/kg. Conclusion: The acute oral median lethal dose (LD ) of methanol extract of the stem bark of L. acida is greater than 3000 mg/kg body weight. 50 Twenty-eight day daily oral doses of more than 250 mg/kg may have nephrotoxic and hepatotoxic effects in Wistar rats. Keywords: Lannea acida, Wistar, toxicity, acute, sub-acute