Antioxidant Properties and Hepatoprotective Potential of Milk Thistle (Silymarin marianum) in Chronic Hepatitis C Patients with Elevated Liver Enzymes

Abstract

Background: Chronic hepatitis C is frequently associated with persistent hepatocellular injury manifested by elevated alanine aminotransferase (ALT) and aspartate aminotransferase (AST), and adjunctive hepatoprotective strategies with antioxidant potential remain of clinical interest. Objective: To characterize milk thistle (Silybum marianum) seed powder and evaluate its hepatoprotective effect on elevated liver enzymes in adult male chronic hepatitis C patients. Methods: In a single-center, parallel-group randomized controlled trial, 45 men (30–50 years) with chronic hepatitis C and elevated transaminases were allocated (1:1:1) to control (no supplementation), milk thistle seed powder 250 mg/day, or 500 mg/day for 45 days. Milk thistle powder underwent proximate analysis, mineral profiling, and phytochemical quantification of total phenolics (TPC) and total flavonoids (TFC). Fasting serum ALT and AST were measured at baseline and day 45. Between-group effects were evaluated using ANCOVA adjusted for baseline values and reported as adjusted mean differences with 95% confidence intervals (CIs). Results: Milk thistle powder contained moisture 25.20±1.77%, ash 16.81±2.13%, nitrogen-free extract 35.10±3.12%, crude protein 7.30±0.72%, crude fat 22.17±2.31%, and crude fiber 5.77±0.11%, with TPC 34.28±0.02 mg GAE/g and TFC 28.36±0.11 mg QE/g. Compared with control, ALT decreased by −11.34 U/L (95% CI: −18.22 to −4.46; p=0.002) with 250 mg/day and −14.05 U/L (95% CI: −21.12 to −6.98; p<0.001) with 500 mg/day; AST decreased by −8.42 U/L (95% CI: −15.01 to −1.83; p=0.013) and −17.31 U/L (95% CI: −24.40 to −10.22; p<0.001), respectively. Conclusion: Milk thistle seed powder supplementation for 45 days significantly reduced elevated ALT and AST in adult males with chronic hepatitis C, with greater reductions at 500 mg/day, supporting a dose-responsive hepatoprotective effect and warranting confirmation in larger placebo-controlled trials.