Thesis Abstract

Abstract
Diabetes mellitus is a metabolic disorder characterized by chronic hyperglycemia and dyslipidemia, leading to various complications. The search for natural remedies to manage diabetes and its associated complications has gained significant attention. Kigelia africana, a plant native to Africa, has been traditionally used for its medicinal properties. This study aimed to investigate the hypolipidemic and antioxidant capacity of the methanol leaf extract of Kigelia africana in alloxan-induced diabetic rats. Diabetes was induced in rats using alloxan, and the animals were treated with the methanol leaf extract of Kigelia africana for 28 days. The effects of the extract on lipid profile, antioxidant enzymes, and histopathological changes in the liver and pancreas were evaluated. The results showed that treatment with the extract significantly reduced the levels of total cholesterol, triglycerides, low-density lipoprotein cholesterol, and very low-density lipoprotein cholesterol in diabetic rats. Additionally, the extract increased the levels of high-density lipoprotein cholesterol, indicating its hypolipidemic effect. Furthermore, the methanol leaf extract of Kigelia africana demonstrated potent antioxidant activity by increasing the activities of superoxide dismutase, catalase, and glutathione peroxidase while reducing the levels of malondialdehyde in diabetic rats. These findings suggest that the extract possesses significant antioxidant capacity, which may help mitigate the oxidative stress associated with diabetes. Histopathological examination of the liver and pancreas revealed that treatment with the extract improved the structural integrity of these organs in diabetic rats. The extract exhibited protective effects against alloxan-induced damage, indicating its potential to preserve the morphology and function of vital organs affected by diabetes. In conclusion, the methanol leaf extract of Kigelia africana demonstrated hypolipidemic effects by improving the lipid profile in diabetic rats. Additionally, the extract exhibited potent antioxidant capacity, protecting against oxidative stress and preserving the histological integrity of the liver and pancreas. These findings support the traditional use of Kigelia africana as a medicinal plant and highlight its potential as a natural remedy for managing diabetes and its associated complications.

Thesis Overview

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:

1. Determine the effects of Kigelia africana methanol leaf extract on antioxidant enzyme.
2. Determine the effects of Kigelia africana methanol leaf extract on lipid profile of diabetic rats.
3. Determine the effects of Kigelia africana methanol leaf extract on oxidative parameters of alloxan-induced diabetic rats.