الفهرس | Only 14 pages are availabe for public view |
Abstract Moringa oleifera is a tropical evergreen tree that has been used in human and animal nutrition. Extracts made from its leaves are widely used in homeopathic medicine in Asia. The leaves are known to be rich in antioxidant compounds. Recently, it has grown commercially and its therapeutic and protective effect has become a field of interest for many researchers. Although, considered safe over the counter analgesic, paracetamol is the most common cause of acute liver failure. Unintentional and chronic overdose accounts for 50% of paracetamol induced acute liver failure. Paracetamol hepatotoxicity is a significant public health concern that is largely attributed to paracetamol combined products prescribed by physicians. The main objective of this study was to investigate the possible protective role of Moringa oleifera leaves aqueous extract on paracetamol induced liver injury in adult male albino rats. Forty adult male albino rats were used in the current study. Animals were divided into four equal groups (ten rats each). group I: control group. group II: rats were given 500 mg/kg body weight of Moringa oleifera leaves aqueous extract by nasogastric tube for 14 days. group III: rats were given water by nasogastric tube for 7 days. On the seventh day paracetamol was given by nasogastric tube in a dose of 400mg/kg body weight for another seven days. group IV: rats were given Moringa oleifera leaves aqueous extract (500mg/kg body weight) by nasogastric tube for 14 days and Paracetamol (400mg/kg body weight) by nasogastric tube on the seventh day for 7days. By the end of the experiment, rats were anaesthetized; blood was collected and liver samples were taken Blood samples were processed for measuring liver function tests (ALT, AST and ALP). Liver samples were handled and the following sections were prepared: A. Paraffin sections were stained by Hematoxylin and Eosin (H&E), Masson’s trichrome stain, Periodic Acid Schiff’s reaction (PAS). The Masson’s trichrome stained sections and the PAS stained sections were further subjected to morphometric analysis for measuring the area% of collagen fibers and area% of PAS positive granules. B. Semithin sections for Toluidine blue stain. C. Ultrathin sections stained for examination by the transmission electron microscope (TEM). Liver samples were also subjected to biochemical analysis to estimate the lipid oxidation marker (Tissue MDA) and antioxidant enzymes (GSHPx and catalase( . Statistical analysis was done for all the results of morphometric and biochemical analysis. Light and electron microscopic examination of the liver sections revealed that Moringa oleifera extract administration in group II didn’t affect hepatic architecture and the hepatocytes. They were nearly similar to that of the control. This was confirmed by the liver function tests (ALT, AST and ALP) which showed no significant difference from the control. Moreover, there was significant increase in GSHPx and catalase activity, antioxidant enzymes, and no significant difference of MDA level, marker for lipid peroxidation, as compared to that of the control. Paracetamol administration, in group III, resulted in profound morphological changes of liver tissue. Most of the hepatocytes appeared swollen with vacuolated cytoplasm. Cellular infiltration and congestion in central and portal veins were observed. An apparent increase in the number of the lining cells of bile ductules was also noticed. The area percentage of collagen fibers was significantly increased as compared to that of the control, while area percentage of PAS positive granules was significantly decreased. Electron microscopic examination of the hepatocytes revealed the presence of vacuoles and fat droplets, elongated and distorted mitochondria and an apparent decrease of rough endoplasmic reticulum with an apparent increase of smooth endoplasmic reticulum. Moreover, HSCs in association with collagen fibrils were frequently seen in between hepatocytes. Microvilli projecting into the lumen of the bile canaliculi were apparently shorter and lacking in some sites when compared to that of the control group. Morphological changes in this study were verified by biochemical analysis as liver function tests showed significant increase in ALT, AST and ALP as compared to that of the control. Tissue GSHPx and Catalase were significantly decreased. On the other hand, tissue MDA was significantly increased as compared to that of the control. In group IV, the administration of Moringa leaf extract prior to paracetamol led to amelioration of the effects of paracetamol on the liver. The hepatocytes appeared comparable to that of the control group. Minimal cellular infiltrations around portal areas were observed. PAS and Masson’s trichrome stained sections showed nearly similar findings as compared to that of the control. These findings were confirmed by the electron microscope examination as hepatocytes and bile canaliculi appeared nearly similar to that of the control. No collagen fibrils were observed associating with HSCs which appeared with lipid droplets in their cytoplasm. Blood liver function tests showed that enzyme levels were nearly similar to control group. Biochemical analysis showed restoration of MDA level, GSHPx activity and catalase activity as compared to that of group III. Consequently, it was concluded that Moringa oleifera extracts could protect the structure and function of the liver against the damaging effects of paracetamol. This hepatoprotective effect is due to inhibition of lipid peroxidation and enhancement of antioxidant enzymes. |