Anti-Hyperglycemic and Anti-Oxidant Activities of Ethanolic Extract of Lantana Camara Leaves

AIM AND OBJECTIVES:Diabetes Mellitus is considered as one of the five leading causes of death in the world. An epidemic by all standards, nearly 250 million people suffer from diabetes across the world. Synthetic anti-diabetic drugs increase the insulin secretion or decrease the blood glucose level but they are also producing many harmful effects. Since, increase in the use of these drugs in diabetes therapy leads to many side effects and undesirable hazards, there is worldwide trend to go back to natural resources, i.e., traditional plant. In industrialized countries the people are seeking for safer alternative to allopathic medicine because of the increasing realization on the adverse side effects of many modern remedies. The current interest in and demand for herbs is a worldwide phenomenon, WHO currently encourages, recommends and promotes traditional/ herbal remedies in national healthcare programmes because such drugs are easily available at low cost, are comparatively safe and people have faith in such remedies On the other hand, the therapeutic approach of several traditional medicinal systems is more holistic. The fundamental mechanisms of these medicinal systems are still unexplainable using modern tools. The medicinal preparations in traditional medicines contain a variety of herbal and non-herbal ingredients that are thought to act on a variety of targets by various modes and mechanisms. Based upon ethanopharmacological survey, the aim of the present work is to evaluate the anti-hyperglycemic and anti-oxidant activities of Lantana camara Leaves by using streptozotocin model in rats.DISCUSSION: Diabetes mellitus is a serious complex chronic condition that is a major source of ill health worldwide. This metabolic disorder is characterized by hyperglycemia and disturbances of carbohydrate, protein and fat metabolisms, secondary to an absolute or relative lack of the hormone insulin85. The number of people in the world with diabetes has increased dramatically over recent years. Indeed, by 2010 it has been estimated that the diabetic population will increase to 221 million around the world86. Present number of diabetics worldwide is 150 million and this is likely to increase to 300 million or more by the year 202587. Reasons for this rise include increase in sedentary lifestyle, consumption of energy rich diet, obesity, higher life span, etc.88. Regions with greatest potential are Asia and Africa, where diabetes mellitus (DM) rates could rise to 2–3-folds than the present rates89. Many herbal medicines have been recommended for the treatment of diabetes90. Plant drugs are frequently considered to be less toxic and freer from side effects than synthetic ones91. STZ induced diabetes cause an increase in blood glucose level in rats92. Our studies show that oral administration of 50 % ethanolic Lantana camara Leaves extract decreases blood glucose in diabetic rats. The increase in the level of lipid peroxides in plasma generally is thought to be the consequence of increased production of and liberation in to the circulation of tissue lipid peroxides due to pathological changes93. This action shows the anti-peroxidative effect of LCE. Changes in the levels of antioxidants are observed in diabetic conditions94. Free radical-induced LPO has been associated with a number of disease processes including diabetes mellitus95. The increase in oxygen-free radicals in diabetes could be due to increase in blood glucose levels, which generate free radicals upon autoxidation96. Glucose auto-oxidases in the presence of transition metal ions generating oxygen-free radicals which make the membrane vulnerable to oxidative damage. The action of diabetes-inducing agents produces reactive free radicals, which have been shown to be cytotoxic to the ß cells of the pancreas97 .The diabetogenic action can be prevented by the superoxide dismutase, catalase and other hydroxyl radical scavengers, such as ethanol and dimethyl urea, hence there is evidence to suggest that the incidence of diabetes involves superoxide anion and hydroxyl radicals. The deleterious effects of superoxide anion and hydroxyl radicals can be counteracted by antioxidant enzymes, such as SOD, CAT etc. There is clear cut evidence to show the role of free radicals in diabetes and studies indicate that tissue injury in diabetes may be due to free radicals98. The capacity of NAE to significantly decrease the elevated blood glucose close to normal level is an essential trigger for the liver to revert to its normal homeostasis during experimental diabetes. These findings coincide with those of the earlier studies which report the antidiabetic activity of the plant by clinical studies99. LPO is also one of the features of chronic diabetes and lipid peroxide-mediated damage has been observed in both type I and type II diabetes mellitus. Under physiological conditions, low concentrations of lipid peroxides are found in tissues, which stimulate the secretion of insulin100 .The involvement of free radicals in diabetes and the role of these toxic species in LPO and the antioxidant defense system have been studied. Depletion of tissue glutathione and increase in LPO have been observed in diabetes. CONCLUSION: The number of people with diabetes is increasing due to population growth, aging, urbanization, and increasing prevalence of obesity and physical inactivity. Quantifying the prevalence of diabetes and the number of people affected by diabetes, now and in the future, is important to allow rational planning and allocation of resources. Diabetes is a disorder of carbohydrate, fat and protein metabolism attributed to diminished production of insulin or mounting resistance to its action. Herbal treatments for diabetes have been used in patients with insulin-dependent and non-insulin-dependant diabetes, diabetic retinopathy, diabetic peripheral neuropathy, etc. Scientific validation of several Indian plant species has proved the efficacy of the botanicals in reducing the sugar level. From the reports on their potential effectiveness against diabetes, it is assumed that the botanicals have a major role to play in the management of diabetes. In recent year several authors evaluated and identified the anti-diabetic potential of traditionally used Indian medicinal plants using experimental animals. Previous studies confirmed the efficacy of several medicinal plants in the modulation of oxidative stress associated with diabetes mellitus. Effect of 50 % aqueous alcoholic extract of plants on serum glucose, lipid profile and antioxidant status in streptozotocin induced diabetic rats was studied. Based on this, potentiation of dreaded disease like diabetes mellitus may shows a ray for better protocol for future treatment. The efficacy of Lantana camara Leaves in experiment showed the significant decrease in the blood glucose level, increase the antioxidant efficacy in streptozotocin induced diabetes. It was demonstrated that the oral administration of the 50% ethanolic Lantana camara Leaves extract to streptozotocin diabetic rats is useful for the treatment of diabetes induced by streptozotocin, because there were significant positive changes in the biochemical and physiological parameters related to carbohydrate, protein and lipids metabolism., the strong anti-hyperglycemic and antioxidant effect observed in STZ induced diabetic rats justifies the use of Lantana camara Leaves for the treatment of diabetes related complications. The present study showed that the ethanolic extract of Lantana camara Leaves not only possess anti-hyperglycemic properties but also antioxidant activity in diabetic condition. These observation and description of mechanism of Lantana camara Leaves, which interplay with diabetes biology and pharmacology lead to rapid development in diabetes treatment. In addition to this, studies on molecular aspect of diabetic therapy will give mechanistic information in diabetes therapy and also critical balance should be there between the animal model and clinical research. This holds great promise for future research in human beings