A Review on Hepatoprotective Activity of Silymarin

Silymarin is obtained from the seeds of Silybum marianum (milk thistle), an edible plant that has been used medicinally from ancient times for the treatment of various liver disorders. It is widely prescribed by herbalists and has almost no known side effects. The plant is native to the Mediterranean and grows throughout Europe, North America, India, China, South America, Africa and Australia. The flavonoid silymarin and one of its structural components, silybin (silybinin), are substances with documented hepatoprotective activities, hence, they have been reported to be effective in liver diseases, including acute and chronic viral hepatitis, toxin/drug-induced hepatitis, and cirrhosis and alcoholic liver diseases. Silymarin has been reported to inhibit the hepatotoxin binding to receptor sites on the hepatocyte membrane; reduce the glutathione (GSH) oxidation to enhance its level in the liver and intestine; and stimulate the ribosomal RNA polymerase and subsequent protein synthesis, leading to enhanced hepatocyte regeneration. Overall, silymarin possesses antioxidant, immunomodulatory, anticancer, antiinflammatory, antihepatoxic and some other pharmacological activities. Its effectiveness against multiple disorders makes it a very promising drug of natural origin.