Hepatoprotective effect of azadirachta indica (NEEM) and tridax procumbens (CHIRAVANAK) in rats

Abstract

The objectives of the present study were to evaluate the hepatoprotective activity of ethanolic extract of Azadirachta indica and Tridax procumbens leaves in paracetamol induced hepatic damage in rats and to compare their action. Forty adult male wistar rats weighing 150-200 g, divided into five groups comprising eight animals in each group, were used for the study. Groups I and II animals were administered with 3 per cent gum acacia suspension in distilled water at the dose rate of 5 ml/kg/day for ten days. Groups III and IV animals received ethanolic extract of Azadirachta indica and Tridax procumbens leaves at the dose of 300 mg/kg and Group V animals received reference drug silymarin at the dose of 100 mg/kg/day in 3 per cent gum acacia for ten days. All the groups except the group I, received paracetamol orally on the eighth day at the dose rate of 2 g/kg in distilled water. Blood was collected from all the groups before and after the experiment for various biochemical and haematological parameters. Body weight was recorded on day 0 and 10th day. All the animals were sacrificed on 10th day and liver was taken for histopathological examination. Phytochemical analysis of the Azadirachta indica (Neem) leaf extract revealed the presence of alkaloids, tannins, flavonoids, glycosides, phenolic compounds, diterpenes, triterpenes and saponins and that of Tridax procumbens (chiravanak) showed the presence of alkaloids, steroids, glycosides, flavonoids, saponins and tannins. Paracetamol administered group showed a decrease in body weight. Liver marker enzymes like ALT and AST were highest in paracetamol treated groups. The elevated levels of these enzymes were decreased by the herbal extracts thereby proving their hepatoprotective activity. A reduction in the total protein was observed in the paracetamol treated group. Both the herbal extracts elevated the total protein level to normal levels. Serum albumin level was also lowest in the paracetamol treated group because of the decrease in the total protein level. Both the extracts increased the serum albumin levels towards normal values. Serum bilirubin level was also highest in the paracetamol treated group Azadirachta indica and Tridax procumbens leaf extract at the dose rate of 300 mg/kg decreased the elevated level of bilirubin. The haematological parameters showed not much significant change with the treatment. From the biochemical studies it was noted that the administration of Azadirachta indica (Neem) leaf extract caused better reduction in serum parameters than that of Tridax procumbens extract. Gross examination of the liver showed normal appearance in all the four groups except the paracetamol treated group in which the liver showed areas of coagulative necrosis and congestion. On histopathological examination the paracetamol treated group showed extensive areas of centrilobular coagulative necrosis. The Azadirachta indica treated animals showed diffuse necrotic areas and fatty changes in certain lobules. The areas of regeneration with binucleate hepatocytes were abundant in this group. The Tridax procumbens treated group showed hypertrophied hepatocytes with vacuolation of cytoplasm and presence of fat droplets. The areas of regeneration with binucleate hepatocytes were scanty in this group. Silymarin treated animals have almost normal liver architecture like the control group. From the present study it can be concluded that the ethanolic extracts of leaves of A.indica and T.procumbens have significant hepatoprotective activities in paracetamol induced hepatotoxicity in rats and A.indica has a better hepatoprotective action compared to T.procumbens.