Thesis Abstract

Abstract
Liver diseases are a significant health concern worldwide, with carbon tetrachloride (CCl4) being a well-known hepatotoxic agent frequently used to induce liver damage in experimental studies. The hepatoprotective properties of medicinal plants have gained attention due to their potential therapeutic benefits. This study aimed to investigate the hepatoprotective effects of Sena tora leaf extract on CCl4-induced liver toxicity in rats. Rats were divided into five groups Group I served as a control, Group II received CCl4 only, Group III received silymarin (standard drug) and CCl4, while Groups IV and V were treated with Sena tora leaf extract at different doses along with CCl4. After the treatment period, various parameters such as liver function tests, oxidative stress markers, and histopathological examination were assessed. The results showed that CCl4 administration led to significant liver damage as evidenced by elevated levels of liver enzymes (AST, ALT, ALP) and oxidative stress markers (MDA, GSH, SOD). However, treatment with Sena tora leaf extract significantly ameliorated these changes in a dose-dependent manner. The extract effectively reduced the levels of liver enzymes and oxidative stress markers while increasing the levels of antioxidant enzymes. Histopathological examination of liver tissues further confirmed the hepatoprotective effects of Sena tora leaf extract, showing reduced liver damage, inflammation, and necrosis compared to the CCl4-intoxicated group. The extract exhibited hepatoprotective activity by preserving the hepatic architecture and reducing lipid peroxidation. In conclusion, Sena tora leaf extract demonstrated hepatoprotective effects against CCl4-induced liver toxicity in rats. The protective mechanisms may involve its antioxidant properties, which help in scavenging free radicals and reducing oxidative stress. The findings suggest that Sena tora leaf extract could be a potential therapeutic agent for liver diseases. Further studies are warranted to elucidate the specific bioactive compounds responsible for the hepatoprotective effects and to explore its clinical applications in liver disorders.

Thesis Overview

INTRODUCTION Many of the developing countries including African countries like Nigeria practice traditional medicine as its main source of health care. This traditional medicine is normally gotten from plant origin [Rehan Ahmad et al, 2008, Stephen bent, 2008].Today nearly 88 percent of the global populations switch to plant derived medicines as their first line of defence for maintaining health and combating diseases [Kintzois et al,2006]. Presently there are about 60 types of medicinal plants that have been recognised in primary health care and are classified according to their pharmacological actions such as peptic ulcers, anti flatulence, laxative, anti diarrhoea and anti hepatic[Viomolos et al,2003]. However in future the discovery of novel therapeutic agents will be only dependent on plant origin [Perulmalsamy et al, 1999].         Senna tora is an example of traditional medicine with pharmacological actions as anticholesterolemic,antispasmodic,carninitative, emolliants, ophthalmic and purgative [Polunin and Stanton,1984,Yeung,1985,Manandhar, 2002]. It can be cardiotonic, antiperiodic, anthelminitic and expectorant and can also be used in treating cogh,leprosy ,ring worm ,colic,flatulence,constipation and other disorders[Nature serve,2007]. Senna tora formally regarded as cassia tora is capable of suppressing the production of prostaglandins and other inflammatory agonists such as cytokines, histamine, kinin and free radical.manila,1998 buttressed his observations confirming its use in the treatment of constipation, edema and liver protection in Korea.         Liver, the largest internal organ of the human body performs more than five hundred functions, all of which are very vital to life. The liver can regenerate or grow back cells that have been destroyed by short term injury or disease, but if the liver is damaged repeatedly over a long period of time, it may undergo irreversible changes which permanently interferes with its function. Carbon tetrachloride is a toxic substance that interrupts the liver and its functions. This is to say that it damages the liver when ingested.CCL4 is stable in the presence of air and light, it is also inflammable. Despite its toxic effect on the liver, it is useful as grain fumigant ,pesticide etc. Equilibrium of the body fluids and secretions are altered as a result of carbon tetrachloride. For instance lipid metabolism, cholesterol metabolism and  biotransformation functions of the liver are terminated or altered in the presence of CCL4.Thus carbon tetrachloride is lethal. The liver produces some enzyme such as aspartate amino transaminases, alkaline phosphatase, lactate dehydrogenase,gamma glutamyl transsferase etc which catalyses the biochemical activities of the body, and on the attack of CCL4 to the liver ,these enzymes will not be produced. Free radicals are highly reactive compounds with uneven number of electrons in their outermost orbit. This can react with cellular compounds like unsaturated fatty acids and can generate new free radicals which result in irreversible biochemical injury like membrane damage, apotosis and cell necrosis. Antioxidants scavenge free radicals and stop the subsequent reactions hence protecting the macromolecules and cellular environment from toxicity and degeneration [Hong B.O. Shao et al, 2008].The oxygen consumption inherent in cell growth leads to the generation of series of reactive oxygen species [ROS].The ROS are molecules such as superoxide anion radicals and hydroxyl radicals[OH]. ROS may be very damaging attacking the lipids of cell membrane and DNA mutation which may further propagate the propagation of many diseases[Valontao et al 2002,Gulcin et al 2003]. Reactive oxygen species are continuously produced during normal Physiological events and are removed by antioxidants defence mechanism [Buyukokuroglu et al,2001]. Many results have shown that some of the cassia species have acquired antimicrobial substances and antioxidant activities.

1.1     AIMS OF THE RESEARCH

The aim of this research is to find out hepatoproductive effects of sena tora leave extract on carbon tetrachloride induced toxicity.