LONG-TERM (12 MONTHS) TREATMENT WITH AN ANTIOXIDANT DRUG (SILYMARIN) IS EFFECTIVE ON HYPERINSULINEMIA, EXOGENOUS INSULIN NEED AND MALONDIALDEHYDE LEVELS IN CIRRHOTIC DIABETIC-PATIENTS

Background/Aims: Several studies have demonstrated that diabetic patie nts with cirrhosis require insulin treatment because of insulin resist ance. As chronic alcoholic liver damage is partly due to the lipoperox idation of hepatic cell membranes, anti-oxidizing agents may be useful in treating or preventing damage due to free radicals. The aim of thi s study was to ascertain whether long-term treatment with silymarin is effective in reducing lipoperoxidation and insulin resistance in diab etic patients with cirrhosis. Methods: A 12-month open, controlled stu dy was conducted in two well-matched groups of insulin-treated diabeti cs with alcoholic cirrhosis. One group (n=30) received 600 mg silymari n per day plus standard therapy, while the control group (n=30) receiv ed standard therapy alone, The efficacy parameters, measured regularly during the study, included fasting blood glucose levels, mean daily b lood glucose levels, daily glucosuria levels, glycosylated hemoglobin (HbA1c) and malondialdehyde levels, Results: There was a significant d ecrease (p<0.01) in fasting blood glucose levels, mean daily blood glu cose levels, daily glucosuria and HbA1c levels already after 4 months of treatment in the silymarin group. In addition, there was a signific ant decrease (p<0.01) in fasting insulin levels and mean exogenous ins ulin requirements in the treated group, while the untreated group show ed a significant increase (p<0.05) in fasting insulin levels and a sta bilized insulin need, These findings are consistent with the significa nt decrease (p<0.01) in basal and glucagon-stimulated C-peptide levels in the treated group and the significant increase in both parameters in the control group Another interesting finding was the significant d ecrease (p<0.01) in malondialdehyde/levels observed in the treated gro up, Conclusions: These results show that treatment with silymarin may reduce the lipoperoxidation of cell membranes and insulin resistance, significantly decreasing endogenous insulin overproduction and the nee d for exogenous insulin administration.