Comparative Hepatoprotective Evaluation of Calotropis gigantea Root and Portulaca oleracea Foliated-Stem Extracts, Alone and in Combination, Against Carbon Tetrachloride-Induced Hepatotoxicity in Wistar Rats

Carbon tetrachloride (CCl4)-induced hepatotoxicity is a well-established experimental model for evaluating hepatoprotective agents, given its reproducible induction of oxidative hepatocellular injury via cytochrome P450-mediated bioactivation to the trichloromethyl free radical [3-6]. This study evaluated the comparative and combined hepatoprotective potential of methanolic extracts of Calotropis gigantea root and Portulaca oleracea foliated stem against CCl4-induced hepatotoxicity in Wistar rats. Extracts were obtained by cold maceration (6.30% w/w and 8.40% w/w yield respectively) and screened for phytoconstituents, both testing positive for flavonoids, alkaloids, glycosides, saponins and tannins. Acute oral toxicity testing (OECD 423) confirmed safety up to 2000 mg/kg, and doses of 100, 200 and 400 mg/kg were selected for the main study. Sixty male Wistar rats were divided into ten groups (n = 6): normal control, CCl4 toxic control, silymarin (50 mg/kg), three dose levels each of C. gigantea and P. oleracea, and a low-dose combination. CCl4 administration markedly elevated serum ALT, AST, ALP and bilirubin and hepatic malondialdehyde while depleting glutathione and body/liver-weight indices; both extracts dose-dependently attenuated these changes, with C. gigantea 400 mg/kg (74.6% hepatoprotection), P. oleracea 400 mg/kg (78.5%) and particularly the combination (85.4%, approaching silymarin's 87.7%) producing the most pronounced normalisation, corroborated by histopathological improvement from severe centrilobular necrosis to near-normal architecture. These findings support a synergistic, antioxidant-mediated hepatoprotective action for the combined extracts, comparable to standard silymarin therapy.