**1. Introduction**

Diabetes mellitus is a heterogeneous primary disorder of carbohydrate metabolism which exists everywhere in the world and interests approximately 371 million people worldwide. The prevalence of diabetes mellitus is increasing with ageing of the population and lifestyle changes associated with rapid urbanization and westernization. The disease is found in all parts of the world and is rapidly increasing in its coverage [1, 2]. WHO projects that diabetes will be the 7th leading cause of death in 2030 [2, 3]. It is a metabolic disorder initially charac‐ terized by a loss of glucose homeostasis with disturbances of carbohydrate, fat and protein metabolism resulting from defects in insulin secretion, insulin action, or both [4]. Without enough insulin, the cells of the body cannot absorb sufficient glucose from the blood; hence blood glucose levels increase, which is termed as hyperglycemia. If the glucose level in the blood remains high over a long period of time, this can result in long-term damage to organs, such as the kidneys, liver, eyes, nerves, heart and blood vessels. Complications in some of these organs can lead to death [5]

The roles of certain organs such as the pancreas, liver and kidney in diabetes mellitus are very important.The pancreas plays a primary role in the metabolism of glucose by secreting the hormones insulin and glucagon (Figure 1). The islets of Langerhans secrete insulin and glucagon directly into the blood. Insulin is a protein that is essential for proper regulation of glucose and for maintenance of proper blood glucose levels [6]. Glucagon is a hormone that opposes the action of insulin. It is secreted when blood glucose level falls. It increases blood glucose concentration partly by breaking down stored glycogen in the liver by a pathway

© 2014 Arise et al.; licensee InTech. This is a paper distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

known as glycogenolysis. Gluconeogenesis is the production of glucose in the liver from noncarbohydrate precursors such as glycogenic amino acids [7].

The conventional treatment for diabetes mellitus is oral hypoglycemic agents/insulin therapy [12]. However these have been shown to have prominent side effects and they do not modify the course of diabetic complications [13, 14]. The need to develop new antidiabetic drugs has led to studies that have attempted to screen some indigenous plants for antidiabetic activity [15, 16]. Traditional preparations of plant sources are widely used almost everywhere in the worldto treatthisdisease.Thereforeplantmaterials are consideredto be the alternative sources for finding out new leads for antihyperglycemic agents. The plant drugs are frequently consideredtobe less toxicwhencomparedto syntheticdrugs [17].More than1,123plant species havebeenusedtotreatdiabetesandmorethan200purecompoundshavebeenshowntopossess characteristics of lowering blood glucose activity [18]. *Acacia ataxacantha* or *Flame Thorn* is an African tree species with conspicuous red pods and numerous hooked prickles. It is wide‐ spread in sub-Saharan Africa from Senegal in the west to Sudan in the east, Namibia, Botswa‐ na, Zimbabwe, and in the Transvaal and KwaZulu-Natal. In arid regions it prefers low-lying sites near streams, water courses and in valleys, but in higher rainfall areas it is a common memberofthevegetation,oftenfavouringforestmargins.Theflakingbarkis lightgrey, splitting longitudinally and transversely, and revealing a buff under-colour. The persistent prickles are profuse on young twigs, but can also be found on older wood. Unlike most Acacias,the prickles

Lipid Profile, Antidiabetic and Antioxidant Activity of *Acacia ataxacantha* Bark Extract in...

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are not in pairs, but scattered along young twigs ('ataxacantha' i.e orderless prickles).

**Source :** Davidson and Jeppe [19]

**Figure 2.** *Acacia ataxacantha*

WHO classification of diabetes introduced in 1980 and revised in 1985 was based on clinical characteristics. The two most common types of diabetes were insulin-dependent diabetes mellitus (IDDM) or (type I) and non-insulin-dependent diabetes mellitus (NIDDM) or (type II). WHO classification also recognized malnutrition-related diabetes mellitus and gestational diabetes. Malnutrition-related diabetes was omitted from the new classification because its etiology is uncertain, and it is unclear whether it is a separate type of diabetes [8, 9, and 10].

International Diabetes Federation [11] reported that one in 10 adults will have diabetes by 2030, posing a huge challenge to health care systems around the world. According to the report, the number of people living with diabetes worldwide will increase to 552 million by 2030 from 366 million in 2011 unless action is taken. Over 80 percent of its related deaths occur in lowand middle-income countries. It has been predicted that the number of cases may jump by 90 percent even in Africa, where infectious diseases have previously been the top killer [11].

**Figure 1.** The role of pancreas in the body

The conventional treatment for diabetes mellitus is oral hypoglycemic agents/insulin therapy [12]. However these have been shown to have prominent side effects and they do not modify the course of diabetic complications [13, 14]. The need to develop new antidiabetic drugs has led to studies that have attempted to screen some indigenous plants for antidiabetic activity [15, 16]. Traditional preparations of plant sources are widely used almost everywhere in the worldto treatthisdisease.Thereforeplantmaterials are consideredto be the alternative sources for finding out new leads for antihyperglycemic agents. The plant drugs are frequently consideredtobe less toxicwhencomparedto syntheticdrugs [17].More than1,123plant species havebeenusedtotreatdiabetesandmorethan200purecompoundshavebeenshowntopossess characteristics of lowering blood glucose activity [18]. *Acacia ataxacantha* or *Flame Thorn* is an African tree species with conspicuous red pods and numerous hooked prickles. It is wide‐ spread in sub-Saharan Africa from Senegal in the west to Sudan in the east, Namibia, Botswa‐ na, Zimbabwe, and in the Transvaal and KwaZulu-Natal. In arid regions it prefers low-lying sites near streams, water courses and in valleys, but in higher rainfall areas it is a common memberofthevegetation,oftenfavouringforestmargins.Theflakingbarkis lightgrey, splitting longitudinally and transversely, and revealing a buff under-colour. The persistent prickles are profuse on young twigs, but can also be found on older wood. Unlike most Acacias,the prickles are not in pairs, but scattered along young twigs ('ataxacantha' i.e orderless prickles).

**Source :** Davidson and Jeppe [19]

**Figure 2.** *Acacia ataxacantha*

known as glycogenolysis. Gluconeogenesis is the production of glucose in the liver from non-

WHO classification of diabetes introduced in 1980 and revised in 1985 was based on clinical characteristics. The two most common types of diabetes were insulin-dependent diabetes mellitus (IDDM) or (type I) and non-insulin-dependent diabetes mellitus (NIDDM) or (type II). WHO classification also recognized malnutrition-related diabetes mellitus and gestational diabetes. Malnutrition-related diabetes was omitted from the new classification because its etiology is uncertain, and it is unclear whether it is a separate type of diabetes [8, 9, and 10].

International Diabetes Federation [11] reported that one in 10 adults will have diabetes by 2030, posing a huge challenge to health care systems around the world. According to the report, the number of people living with diabetes worldwide will increase to 552 million by 2030 from 366 million in 2011 unless action is taken. Over 80 percent of its related deaths occur in lowand middle-income countries. It has been predicted that the number of cases may jump by 90 percent even in Africa, where infectious diseases have previously been the top killer [11].

carbohydrate precursors such as glycogenic amino acids [7].

4 Antioxidant-Antidiabetic Agents and Human Health

**Source:** Worthley [6]

**Figure 1.** The role of pancreas in the body

Hence, the aim of this study is to investigate the anti-diabetic potential and safety evaluation of ethanolic extract of *Acacia ataxacantha* bark in streptozotocin-induced diabetic rats. The results were compared with standard anti-diabetic drug, metformin.

Group 4: Diabetic and treated with 250 mg/kg b.w of ethanolic extract of *Acacia ataxacantha*

Lipid Profile, Antidiabetic and Antioxidant Activity of *Acacia ataxacantha* Bark Extract in...

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Group 5: Diabetic and treated with 500 mg/kg b.w of ethanolic extract of *Acacia ataxacantha* bark

At the end of the experimental period, venous blood was collected from the experimental animals and serum was prepared by centrifuging the blood samples at 3000 rpm for 5 minutes [23] and serum collected by pippeting. The animals were thereafter quickly dissected and the liver and pancreas removed. The pancreas and liver were suspended in ice-cold 0.25 M sucrose solution (1:5 w*/*v) and homogenized. The homogenates were kept frozen overnight to ensure

Hepatic glucose and glycogen were estimated using the method of Barham and Trinder [25]

The method described by Reitman and Frankel [27] was used for assaying the activity of

Total cholesterol, triglyceride, high density lipoprotein cholesterol, low density lipoprotein cholesterol were assayed using the method of Zlakis *et al.* [28], Foster and Dunn [29], Burstein

The procedure described by Doumas *et al.* [32] and Sherlock [33] was used for the determina‐

The method of Tietz *et al*. [34] was used to determine the levels of serum urea and creatinine.

**2.10. Determination of superoxide dismutase activity and malondialdehyde concentration** The pancreatic superoxide dismutase activity was determined by the method of Misra and Fridovich [35] while malondialdehyde concentration was assayed using the method described

All data are expressed as the mean of sixth replicates ± standard error of mean (S.E.M). Statistical evaluation of data was performed by SPSS version 16 using one way analysis of

Group 6: Diabetic and treated with standard drug (Metformin)

bark.

**2.5. Sample preparation**

maximum release of enzymes [24].

**2.8. Lipids profile analysis**

by Varshney and Kale [36].

**2.11. Statistical analysis**

**2.6. Estimation of hepatic glucose and glycogen**

and Passoneau and Lauderdale [26] respectively.

alanine aminotransferase and aspartate aminotransferase.

tion of albumin and bilirubin concentrations respectively.

**2.7. Determination of liver enzyme activities**

*et al.*[30] and Friedwald *et al.* [31] respectively.

**2.9. Determination of liver function indices**
