Safety profile and gender specific differences of a methanol extract of Eriosema laurentii (Leguminosae) in acute and subchronic (28 days) oral toxicity studies in Wistar rats

Despite widespread use of Eriosema laurentii De Wild (Leguminosae) in West and Central Africa as herbal medicine and food additive the toxicity of this plant is unknown. Therefore, we performed the safety evaluation of a methanol extract (AEL). In acute toxicity, single oral administration of 2000 mg/kg AEL caused neither toxicological symptoms nor mortality and the LD50 was estimated >5000 mg/kg. In the subchronic oral toxicity, AEL induced no phenotypical signs of toxicity during and after treatment. Only a delayed decrease of relative spleen weight in males at the highest dose of 400 mg/kg occurred. High density lipoprotein (HDL) increased significantly in females at 200 and 400 mg/kg. Non-persistent increases in alanine aminotransferase activity within normal ranges were noted at 200 mg/kg in males and at all doses in females. In males, AEL induced a decrease of white blood cell count at 400 mg/kg, whereas lymphocytes increased at 200 and 400 mg/kg and granulocytes at 400 mg/kg. In females, no differences in haematological parameters occurred. Neither differences in bilirubin, creatinine and total protein levels were observed nor histological alterations in organs. The results indicate a broad safety margin for AEL.