Diabetes mellitus is a metabolic disorder resulting from the presence of excess sugar in the blood as a result of defect of insulin secretion, insulin action or both. Insulin deficiency in turn leads to chronic hyperglycaemia with disturbances of carbohydrate fat and protein metabolism. Globally it has been estimated that the incidence of diabetes and project for year 2030, as given by international diabetes federation is 350million. This work is aimed at evaluating the antioxidant potential and hypolipidemic properties of the plant. Methanol leaf extract of Kigelia africana used for the study. Alloxan diabetes was induced into 20 rats and the rats weighed 125g. They were grouped into four groups: group 1 Normal control group, group 2 diabetes not treated, group 3 diabetes treated with 0.6 g of modern drugs (glibenclamide), group 4 diabetes treated with 500 mg/kg body weight of the extract of K.africana orally for 14days. At the 14th day, rats were bled and blood samples obtained were used for parameter analysis. From the result, glucose level increased as the body weight of the rats in all test groups decreases when compared with normal control (group 1). Oral administration of K.africana causes an increase although not significant (P˂0.05) of MDA in the test group treated with leaf extract of K.africana (group 4) compared with other test groups. The result also showed a significant increase (P˂0.05) in Catalase (CAT) activity in diabetic rat treated with glibenclamide (group 3) and rats treated with leaf extract (group 4) when compared with normal groups (group 1&2). A significant increase (P˂0.05) was observed in the cholesterol level of diabetic rats treated with K.africana when compared with group1and 2. High density lipoprotein increased significantly (P˂0.05) in the test group (group 4) when compared with other test groups. Low density lipoprotein decreased significantly (P˂0.05) in the test group treated with K.africana leaf extract (group 4) compared with normal control (group 1). Therefore, from the results gotten, it can be said that Kigelia africana has an hypolipidemic and antioxidant Capacity in diabetic conditions.
TABLE OF CONTENTS
Title Page i
Table of Content v
List of Tables vi
List of Figures vii
CHAPTER ONE: INTRODUCTION
1.1 Background of the Study 1
1.2 Statement of the Problem 2
1.3 Aims of Study 3
1.4 Objective of Study 3
CHAPTER TWO: LITERATURE REVIEW
2.1 Scientific Classification 4
2.2 General Information 5
2.2.1 Ecology 6
2.2.2 Traditional uses 7
2.3 Chemical constituent of Kigelia africana 8
2.4 Medicinal properties of Kigelia africana 9
2.4.1 Antidiabetic and antioxidant activity 9
2.4.2 Anti-inflammatory and analgesic activity 10
2.4.3 Anti-ulcer activity 11
2.4.4 Anti-cancer activity 11
2.4.5 Anti-diarrhoeal activity 12
2.4.6 Diuretic activity 13
2.5 Antioxidant 13
2.5.1 Antioxidant Defence System 15
2.5.2 Mechanisms of actions of Antioxidants 15
2.5.3 Levels of Antioxidant actions 15
2.6 Lipid peroxidation 17
2.6.1 Stages of Lipid Peroxidation 17
2.6.2 Malondialdehyde 18
2.7 Alloxan 18
2.7.1 Mechanisms of actions 19
CHAPTER THREE: MATERIALS AND METHODS
3.1 Chemicals 20
3.1.1 Reagents 20
3.1.2 Equipment 20
3.2 Collection of Leaves 20
3.3 Preparation of plant extracts 20
3.4 Animal Care 21
3.4.1 Animal grouping and preparation of extract for administration 21
3.5 Alloxan Mode of Administration 21
3.6 Collection of Blood 21
3.7 Assessment of Biochemical parameters 22
3.7.1 Determination of Glucose level 22
3.7.2 Assessment of Lipid peroxidation 23
3.7.3 Determination of catalase activity 24
3.7.4. Determination of total cholesterol concentration 25
3.7.5 Determination of HDL- Cholesterol concentration 27
3.7.6 Determination of LDL- cholesterol concentration 28
Representation of results graphically 30
5.1 Discussion 37
5.2 Conclusion 40
5.3 Recommendation 40
1.1 Background of study
Diabetes mellitus is a metabolic disorder resulting from a defect of insulin secretion, which is insulin action or both. Insulin deficiency in turn leads to chronic hyperglycaemia with disturbances of carbohydrate fat and protein metabolism (Kumar et al., 2011).
Globally the estimated incidence of diabetes and project for year 2030, as given by international diabetes federation is 350million (Ananda et al., 2012). Currently available pharmotherapies for the treatment of diabetes mellitus include oral hypoglycaemic agent and insulin. However these current drugs do not restore normal glucose homeostasis and they are free from side effects (Bandawane et al., 2011).
In view of the adverse effect associated with the synthetic drugs and as plants are safer, cheaper, and as much effective. Conventional and anti-diabetic plants can be explored (Kumar et al., 2010). Over 400 traditional plants have been reported for the treatment of diabetes (Ramachandran et al., 2011).
Furthermore after world Health Organisation recommended investigation of hypoglycaemic agents from medicinal plants has become more important (Kumar et al., 2010). Also diabetes has been treated orally with several medicinal plants or their extract based on folklore medicine since ancient times.
Kigelia africana (Lam) Benth (Family: Bignoniaceae) is widely distributed in south central and West Africa. It is known as the cucumber or sausage tree because of its huge fruits (average 0.6cm in length and 44kg in weight) which hang from fibrous stalks. It is also known as balm Khene in Hindi and it is distributed all over India but found in abundance in West Bengal. It is found mostly in water areas and spreads abundantly across wet savannah and riverine areas (Sofowaora et al., 1980).
Experimentally, the plant has shown antibacterial, antifungal, antineoplastic, analgesic, anti-inflammatory and antioxidant properties (Saini et al., 2009). The roots, the wood and leaves have been found to contain kigelinone, vernolic acids, kigelin, iridoids, luteolin and 6-hydroxyluteolin (Picerno et al., 2005). Crude extract of herbs and species and other materials rich in phenolic are of increasing interest in the food industry because they retard oxidative degradation of lipids and thereby improving the quality and nutritional value of food (Frankel, 1995).
The baked fruits of Kigelia africana are used for fermentation of beer. It also has internal application including treatment of dysentery, ringworm, tapeworm, malaria, diabetes, pneumonia, haemorrhage and tooth care (Gills, 1992).
In West Africa, the roots and unripe fruit are used as vermifuge and as treatment for haemorrhoids and rheumatism. The bark is traditionally used as remedy for syphilis and gonorrhoea. The fruits and bark ground and boiled in water are taken orally or used as an enema in treating children’s stomach ailment usually tapeworm (Walt et al., 1962)
1.2 Statement of the problem
As impressive improvement has occurred in global health status in the past century which has become a cause for celebration. Therefore, public health professionals can feel proud of their contribution to these achievements even as they appreciate the complexity of the underlying driving force, many of which lie outside traditional public health work. But this satisfaction must be tempered by emerging concerns (Sen and Bonita, 2000) against the recent evidence suggesting that based current trends many low income countries are unlikely to achieve desired health target by 2015 due to devastating disease and overwhelming failing health system (Travis et al., 2004).
The literature review survey revealed that there is no experimental evidence of antidiabetic and hypolipidemic effect of the plant. Therefore the present work was undertaken to explore the antidiabetic and hypolipidemic potential of Kigelia africana methanol leaf extract of the plant in alloxan induced diabetic rats.
1.3. Aim of the study
The research is aimed at investigating the hypolipidemic and antioxidant capacity of methanol leaf extract of Kigelia africana in alloxan induced diabetic rats.
1.4 Objective of the study
Specifically the study sort to: