Hepatoprotective and Hypoglycemic activities of Morinda tinctoria leaves extract on alloxan induced diabetic albino rats.

The present study explores the hepatoprotective and hypoglcemic effect of Morinda tinctoria in alloxan induced diabetic rats. Alloxan (120mg/kg body weight of rats) induces chemical diabetes in a wide variety of animal species through damage of insulin secreting cell. The M. tinctoria leaf extract was prepared with ethanol and ethyl acetate solvents. Preliminary phytochemical screening of phenols, flavonoids, alkaloids, terpenoids and tannins were performed by standard protocols. Compounds responsible for these activities were identified by GC-MS with the inbuilt libraries. After 35 days of oral administration of M. tinctoria ethanol (250 mg/kg b.w) and M. tinctoria ethyl acetate (200 mg/kg b.w) extracts treatment, the physical and biochemical parameter such as body weight, blood glucose, lipid profile, hepatic markers and antioxidant parameters are assayed. Hypoglycemic activity may due to its stimulatory effect at cellular level on islets. Ethyl acetate extract of M. tinctoria produced more significant reduction in glucose, HbA1C, lipid profile, and enhanced hepatic marker enzymes and antioxidant activity in alloxan induced diabetic rats. Ethyl acetate extract yielded more promising results than the ethanol extract and even more or less same with the drug glibenclamide. The preliminary investigation on the hepatoprotective and hypoglycemic efficacy of ethyl acetate extract of M. tinctoria exhibit significant role due to its high alkaloid, terpenoid, coumarin and polyphenol contents. Further studies will be carried out to elucidate its active fraction and its mechanism of action. V.Ramasubramanian K.Palanivelu PG & Research Department of Zoology, Government Arts College (Auto), Kumbakonam, Tamil Nadu, India. PG & Research Department of Zoology, Government Arts College (Auto), Kumbakonam, Tamil Nadu, India. Introduction Diabetes mellitus is a chronic disease which cannot be completely cured and may develop complications if not properly regulated. It’s one of the most common noncommunicable diseases globally. It has been associated with a syndrome of disturbance in the homeostasis of carbohydrate, fat and protein metabolism. Diabetes is primarily characterized by a hyperglycemia which results from lack of insulin or a weak response of tissues to this hormone. It is associated with long-term complications such as coronary artery and peripheral vascular disease, stroke, diabetic neuropathy, retinopathy, amputations, renal failure and blindness. The prevalence of diabetes mellitus is growing rapidly worldwide and is reaching epidemic proportions. Diabetes is undoubtedly one of the most challenging health problems in 21st century (Gohel et al., 2013). Diabetes mellitus has been classified into several subtypes based on its etiology (Rabi et al., 2006). Chiefly there are two types, type I diabetes (IDDM) and type II diabetes (NIDDM). Type I diabetes refers to endogenous insulin which is caused by a cellular-mediated autoimmune destruction of beta cells in pancreas, leads to increased blood and urine glucose levels. Type II diabetes is also known as Non-Insulin Dependent Diabetes Mellitus (NIDDM) or “adult onset diabetes” is developed due to lack of insulin and is the most widespread form of diabetes which accounts for 95% of cases. It has been proved that T2D is caused due to unhealthy life style such as smoking, alcohol, sedentary life and consumption of high calorie food (Misra Anoop et al., 2007). Current status of diabetes is estimated around 6% of the world’s adult population now lives with diabetes (Meetoo et al., 2007). It is estimated that there are currently 285 million people with diabetes worldwide and this number is set to increase to 438 million by the year 2030. Synthetic antidiabetic agents like sulfonylurea, biguanides, glucosidase inhibitors and thiazolindiones are being expensive and produce serious side effects. Many indigenous Indian medicinal plants have been found to be useful to successfully manage diabetes and some of them have been tested and their active ingredients isolated. The World Health Organization (WHO) has also recommended the evaluation of the plants effectiveness and conditions where we lack safe modern drugs. Hence phytotherapy has significant role to play in the developing countries compared to synthetic drugs because it is safe, less expensive and available as a gift of nature. Morinda tinctoria belongs to the family of Rubiaceae that grows wild and is distributed throughout Southeast Asia. It is commercially known as Nunaa and is indigenous to tropical countries. M. tinctoria is considered as an important folklore medicine. The tribes of Australia have used the ripe fruits of M. tinctoria for the treatment of respiratory infections. In the traditional system of medicine, leaves, fruits and roots of M. tinctoria are used as astringent, deobstrent, emmengogueand to relieve pain in the gout (Thirupathy Kumaresan et al., 2009). Further, it has been reported to have a broad range of therapeutic and nutritional values. There is a greater demand for its fruit juice in treatment for arthritis, cancer, gastric ulcer and other heart diseases (Sivaraman et al., 2010). Anticonvulsant, analgesic, antiinflammatory, antioxidant and cytoprotective effect of M. tinctoria leaves has been reported (Thirupathy kumaresan et al., 2009; Pattabiraman et al., 2011; Jeyabalan et al., 2009; Sivaraman et al., 2010). There was not much work has been carried out on hepatoprotective and hypoglycemic activities in vivo, the present study was designed to investigate the efficacy of leaves of M. tinctoria in alloxan induced diabetic rats. 2. Materials and Methods 2.1. Preparation of extracts The leaves of M. tinctoria were collected from the banks of Cauvery river at Government Arts College(A), Kumbakon-