Research Article ANTIHYPERGLYCEMIC AND LIPID LOWERING EFFECT OF TERMINALIA ARJUNA BARK EXTRACT ON STREPTOZOTOCIN INDICED TYPE 2 DIABETIC MODEL RATS M. ALAM MORSHED 1, 4 * , ANWARUL HAQUE 1, 3 , BEGUM ROKEYA 2 , LIAQUAT ALI 2 1 Dept. of Biotechnology & Genetic Engineering, Faculty of Applied Science & Technology, Islamic University, Kushtia7003, Bangladesh, 2 Biomedical Research Group, BIRDEM, 122, Kazi Nazrul Islam Avenue, Dhaka1000, Bangladesh, 3 Department of Physiology & Cell Biology, Graduate School of Medicine, Kobe University, 751, Kusunokicho, Chuoku, Kobe 6500017, Japan, 4 Department of Internal Medicine, College of Medicine, Jeju National University School of Medicine, Jeju, Republic of Korea. Email: morshedbt@gmail.com Received: 19 May 2011, Revised and Accepted: 9 July 2011 ABSTRACT The present study was carried out to evaluate the antidiabetic and antilipidemic property of Terminalia arjuna in streptozotocin‐induced type ʹ diabetic model rats. ͷͲ% ethanol extract of stem bark of Terminalia arjuna were administered ͳ.ʹͷgkg‐ͳ body weight for ʹͳ consecutive days to type ʹ diabetic male Long‐Evans rats. Ethanol extract of T. arjuna significantly ȋp<Ͳ.ͲͷȌ improved oral glucose tolerance in type ʹ rats in comparison to control group at the end of study period. )t was also found that fasting serum glucose level decreased significantly ȋp<Ͳ.ͲͷȌ compared to water control after ʹͳ days of feeding of T. arjuna. (owever, no change was observed in the liver glycogen content and serum insulin level at the end of the study period. )n addition to hypoglycemic effect of T. arjuna, beneficial effect was also observed in lipid profile. Serum total cholesterol and triglyceride were decreased significantly by ȋp<Ͳ.ͲͳȌ and ȋp<Ͳ.ͲͲͳȌ at the end of the study period. Administration of Glibenclamide ȋͷ mgkg‐ͳȌ also produced significant reduction ȋp<Ͳ.ͲͳȌ in serum glucose concentration in type ʹ diabetic rats. Thus, the results of the experimental study suggest that T. arjuna possesses hypoglycemic and hypolipidemic effects and can be served as a source of potent antidiabetic agent. Keywords: Anti‐hyperglycemic, Anti‐atherosclerotic, Terminalia arjuna ȋCombretaceaeȌ, Streptozotocin, Type ʹ diabetes. INTRODUCTION Diabetes mellitus is a disease due to abnormality of carbohydrate metabolism and it is mainly linked with low blood insulin level or insensitivity of target organs to insulin. )t is the most prevalent chronic disease in the world affecting nearly ʹͷ% of the populationͳ. (yperglycemia and hyperlipidemia are two important characters of diabetes mellitus, an endocrine disorder based disease. )n modern medicine, no satisfactory effective therapy is still available to cure diabetes mellitusͳ. Though pharmaceutic drugs like sulfonylureas and biguanides are used for the treatment of diabetes but these are either too expensive or have undesirable side effects or contraindicationsʹ, ͵. )n recent years, there has been renewed interest in plant medicineͶ, ͷ, ͸ for the treatment against different diseases as herbal drugs are generally out of toxic effect͹, ͺ reported from research work conducted on experimental model animal. Although in human, whether there is any toxic effect are not investigated, isolated studies screened various plants having Dzfolk medicine reputationdz by biochemical test for this for antidiabetogenic effectͻ. Terminalia arjuna ȋfamily ‐ CombretaceaeȌ, a large tree, is found throughout the South Asian region. )t is one of the most versatile medicinal plants having a wide spectrum of biological activityͳͲ, ͳͳ. Traditional healers claim that the stem bark of the plant possess antidiabetic properties. Scientific reports also support the hypoglycemic activity of this plantͳʹ. (owever, no published report supports both the acute and chronic hypoglycemic effect of T. arjuna on streptozotocin induced Type ʹ diabetic model rats. As the majority of the diabetic population suffers from Type ʹ diabetes, we undertook the present study to evaluate the anti‐diabetic effect on Type ʹ diabetic model rats and to explore the possible hypoglycemic / anti‐hyperglycemic and lipid lowering activity of the extract as well as to investigate the possible chemical constituents responsible for the activity and the target tissueȋsȌ involved in this action. MATERIALS AND METHODS Plant materials and preparation of test sample The barks of Terminalia arjuna were collected from Khamarpara, a village of Magura, Bangladesh. The plant was identified by the Bangladesh National (erbarium, Dhaka and the specimens were stored in there for the further reference ȋVoucher Specimen No. DACB‐͵ͷʹ͵ͷȌ. The stem barks of the T. arjuna were cut into small pieces and then water washed carefully. After washing, the fresh barks were air dried and then oven dried at ͶͲ°C temperature. The dried barks are then grinded to make powder, which were then screened to get fine powder. ͳͷͲͲg of barks were dried in oven and finally ͷͲͲg of fine powder was obtained. ͷͲͲg of dried bark powder were soaked in ͷͲ% ethanol. These suspensions were filtered with thin and clean cloth and then filtered by filter paper. The suspensions were evaporated by BUC() Rota vapor R‐ͳͳͶ [BUC(), Germany], connected with BUC() water bath B‐ͶͺͲ at ͷͲͲC. )n this case, ͳ͹ͷmbar ȋto remove ethanolȌ, ͹ʹmbar ȋto remove waterȌ pressure and ͳ͸Ͳrpm rotation speed were maintained constantly. Finally, small amount of liquid were evaporated from the semi‐solid extracts by using a freeze‐drier ȋ(ETOS)CC, (eto Lab Equipment, DenmarkȌ and ͹ͷ g of ethanol extracts were obtained. Phytochemical Screening The freshly prepared crude extract was qualitatively tested for the presence of chemical constituents. Phytochemical screening of the extract was performed using the following reagents and chemicals: Alkaloids with Molischǯs reagent, flavonoids with the use of Mg and (Cl; tannins with ferric chloride solutions and saponins with ability to produce stable foam and steroids with Libermann‐ Burchard reagent. Gum was tested using Molish reagent and concentrated sulphuric acid; reducing sugars with Benedictǯs reagent; terpenoids with chloroform and conc. sulphuric acid. These were identified by characteristic color changes using standard proceduresͳ͵. Experimental Animals The study was conducted with adult male Long‐Evans rats ȋweighing ͳ͸Ͳ‐ʹͳͲgȌ. They were bred at the B)RDEM animal house maintained at a constant room temperature of ʹʹ±ͷͲC, ͶͲ‐͹Ͳ% humidity conditions and the natural day‐night cycle with an ad libitum access to food except the day of experimental procedure when animals were used after ͳʹhrs fasting. The rats had no access to food during International Journal of Pharmacy and Pharmaceutical Sciences ISSN- 0975-1491 Vol 3, Issue 4, 2011 A Ac c a a d d e e m mi i c c S Sc c i i e e n n c c e e s s