CHAPTER ONE
1.0 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 al2003].
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