Vol. 9, Issue 10, Part F (2025)

The present study evaluated the subacute toxicity of alcoholic extracts of Catharanthus pusillus (Murray) G. Don (CPE) in Wistar rats in accordance with OECD Test Guideline 407. Forty healthy rats (20/sex) were divided into four groups (I-IV; n = 10/group). Group I served as control (distilled water), while Groups II-IV received CPE orally at 750, 1500, and 3000 mg/kg body weight, respectively, for 28 consecutive days. All animals survived until terminal sacrifice, and no treatment-related effects were observed on body weight, hematology, or clinical chemistry, except for a minimal increase in platelet counts in females of Groups II and IV. Absolute and relative spleen weights were increased in treated males, while relative liver weight was elevated in Group IV males. Histopathology revealed hepatocellular necrosis in two male animals of Group IV and splenic lymphoid hyperplasia in male animals of Groups II, III and IV, whereas no other test article-related microscopic changes were noted. Immunohistochemistry demonstrated increased CYP2E1 expression following CPE administration, with no effect on CYP3A1. Based on these findings, a No Observed Adverse Effect Level (NOAEL) could not be established.