Protective Effect of Wrightia tinctoria Bark Triterpenoidal Fraction on Carbon Tetrachloride- Induced Acute Rat Liver Toxicity

The present investigation aims at assessing the hepatoprotective effect of triterpene fraction isolated from the stem bark of Wrightia tinctoria (containing lupeol, β-amyrin and β-sitosterol) on CCl4-induced hepatotoxicity in the rat. CCl4 (1.5 mg/kg, i.p) is a potent hepatotoxic agent which causes peroxidative degeneration of membrane lipids with the potential outcome of fatty degeneration. The peroxidative products induce hypoperfusion of the membrane and cytosolic enzymes appear in the blood, elevation of serum marker enzymes namely SGPT, SGOT and ALP and decrease in hepatic glutathione and SOD. The hepatoprotection of triterpene is compared with silymarin, a well known standard hepatoprotectant. Pretreatment with triterpene fraction (125, 250 and 400 mg/kg, p.o. once a day for 4 days before CCl4 and continued further 3 days) attenuated the CCl4-induced acute increase in serum SGPT, SGOT and ALP activities and considerably reduced the histopathological alterations. Further, triterpene fraction reduced thiopentone-induced sleeping time, suggesting the protection of liver metabolizing enzymes. Triterpenes administration changed the tissue redox system by scavenging the free radicals and by improving the antioxidant status of the liver replenished the depleted hepatic GSH and SOD. Triterpene pretreatment improves bromosulphalalin clearance of the CCl4-intoxicated liver and also increases the cellular viability. These effects substantiates protection of cellular phospholipid from peroxidative damage induced by highly reactive toxic intermediate radicals formed during biotransformation of CCl4. Triterpene fraction afforded protection against the hepatic abnormalities due to presence of lupeol and β-amyrin. This study supports the traditional use of W. Tinctoria bark in liver diseases.