Evaluation of Acute and Subacute Toxicity of Aqueous Extract of Picralima nitida Seeds in Wistar Rats

Picralima nitida (Stapf.) Durand and Hook, (fam. Apocynaceae) is a widely used medicinal plant in the traditional treatment of ailments such as malaria, diabetes, hypertension, and inflammation in West Africa. The study assessed the acute and subacute toxicity of aqueous extract of Picralima nitida (AEPN) seed in Wistar rats. In the acute phase, female Wistar rats weighing 170 ± 10 g were employed, and the treatment group received a single oral dose of 5,000 mg/kg body weight of AEPN, while the control group received distilled water only. Male and female healthy rats, divided into four groups each (n = 5) were used for the subacute toxicity study. Each of the groups in either gender was administered orally with 0, 250, 500 and 1000 mg/kg b.w. AEPN daily for 28 days. Observations focused on adverse effects, behavioral changes, mortality and morbidity, with satellite groups assessing recovery post-treatment. Rats were sacrificed on the 29th day and biochemical parameters, such as liver and kidney function markers were investigated. There were no significant changes in the body weights of rats, no mortality, as well as no observed behavioral and physical changes during the 14-day recovery period of the acute toxicity study. During the 28-day exposure, no significant changes were noted in the parameters such as liver and kidney function markers and hematological parameters, up to 1,000 mg/kg AEPN, compared to control. The LD50 of AEPN was greater than 5,000 mg/kg, indicating that doses up to 1,000 mg/kg may be considered safe for potential medicinal applications.