Acute and Sub-acute Toxicity Studies of Senna alata on Mice and Wistar Rats

Abstract

This study investigated the acute and subacute toxicological effects of aqueous and methanol leaf extracts of Senna alata in experimental animals. For the acute toxicity assessment, 25 mice were divided into five groups and administered oral doses of 2,000 or 3,000 mg/kg body weight (bw) of either aqueous (AES) or methanol (MES) extract. In the 28-day subacute study, 36 Wistar rats received daily oral doses of 500, 1,000, 2,000, or 3,000 mg/kg bw of AES or MES. The extraction yields were 6.2% for AES and 7.9% for MES. Biochemical and haematological indices, together with liver and kidney histopathology, were evaluated. No mortality, abnormal behaviour, or other overt signs of toxicity were observed, and the median lethal dose (LD₅₀) of both extracts exceeded 3,000 mg/kg. Body weight and relative organ weights did not differ significantly between treated and control animals. Serum alanine aminotransferase (ALT) increased from 30.3 IU/L in controls to 39.4 and 43.5 IU/L following 2,000 mg/kg AES and MES, respectively, and to 51.6 and 54.8 IU/L at 3,000 mg/kg. Aspartate aminotransferase (AST) similarly increased from 57.3 IU/L in controls to 67.1 and 68.5 IU/L at 2,000 mg/kg and 73.1 and 79.5 IU/L at 3,000 mg/kg (p<0.05). Other biochemical indices remained largely unchanged. Haematological parameters were generally unaffected, although platelet counts increased significantly at higher doses (p<0.05). Renal histology remained normal, whereas high-dose treatment produced mild hepatic sinusoidal dilation and portal inflammation. The extracts therefore exhibited low acute toxicity, although prolonged or high-dose exposure may induce mild hepatic stress.