ANTIHYPERGLYCEMIC POTENTIAL OF TEAK SEEDS IN ALLOXAN INDUCED DIABETIC RATS

ANTIHYPERGLYCEMIC POTENTIAL OF TEAK SEEDS IN ALLOXAN INDUCED DIABETIC RATS

G. Jhansi Rani and N. Lakshmi Bhavani ^*

Department of Botany, University College of Science Saifabad, Osmania University, Hyderabad - 500004, Telangana, India.

ABSTRACT: Tectona grandis is famous as a valuable timber hold an extensive range of applications around the sphere. In addition to its enormous uses in the timber industry, all the parts are cherishing with extensive use in traditional medicine and possess significant pharmacological properties. In search of drugs for diabetes, the methanolic seed extract which is prepared by the Soxhlet apparatus, was used for investing the bioactive compounds and anti-hyperglycemic potential in alloxan-induced diabetic rats. The results revealed that preliminary phytochemical analysis revealed the presence of distinct secondary metabolites like xanthones, glycosides, flavonoids, saponins, proteins, amino acids, and carbohydrates. The extract exhibited significant diminution in blood glucose levels in the given alloxan-induced diabetic rat model at 100 mg/kg and 200mg/kg dose using metformin as a reference standard.

Tectona grandis, Anti-hyperglycemic, Alloxan, Acute toxicity, Phytochemical screening

INTRODUCTION: Both types I and II diabetes are one of the progressive metabolic disorders. It is also one of the major community health problems over the globe. Diabetes is not a single disease; it is a cumulative disorder with chronic illness. It ravens the other metabolism in the body and develops diabetic complications. Symptomatically it can be identified by hyperglycemia, polyphagia, polyuria and polydipsia. Indian traditional ayurvedic system is having elaborated medicinal use of plants. Current trends in the plant research lead to a handful of literature about the plants bearing antihyperglycemic properties.

The current aim of the work is to identify the potency of Tectona grandis seeds to exhibit antihyperglycemic activity in alloxan-induced diabetic adult wistar rats. Tectona grandis Linn. is a big deciduous tree 30-35 meters tall. It is a well-known tree for its typical strong trunk and durability, having a good commercial value in the timber industry ¹. The entire tree possesses valuable applications to heal numerous diseases.

The plentiful literature discloses the uses of different plant parts of Tectona grandis in the management of nociception ², diabetes ³, dermatological complications ⁴, hypertension ⁵, as anti-ulcer ⁶, antibacterial ⁷, antiviral ⁸ anti-inflammatories ⁹, antifungal ¹⁰, antipyretic ¹¹, antioxidant ¹², anticancer ¹³ and hair growth-promoting activities ¹⁴. In agroforestry, the teak plants are cultivated along with other crops like maize to get weedicide and antifeedant properties. This helps to improve crop harvesting and yield ¹⁵.

MATERIALS AND METHODS:

Plant Material: Tectona grandis fruits were collected in the month of February 2017 in Hyderabad and were identified by Dr. N. Sivaraj, Senior Scientist (Eco Botany), National Bureau of Plant Genetic Resources, Rajendranagar, Hyderabad, seed specimens have been deposited (OU/DB/VS-257).

Extraction: Five kilograms of the fresh seeds were shade dried at temperature 25-30 ºC for 7 days. The dried seeds were powdered in a grinder. The alcoholic extract of the seeds was prepared by subjecting to repetitive maceration for 2 weeks with methanol after defatting with n-hexane. The extract was evaporated to dryness with rotary evaporator and lyophilized to get powder. The percentage of yield was calculated as 6% and the final methanolic extract was used for the analgesic activity studies.

Phytochemical Screening: By using standard experimental procedures, the methanolic seed extract of Tectona grandis were screened for the presence of various phytochemicals ¹⁶.

Experimental Animals: Adult Wistar rats (8-10 weeks) were used for the pharmacological screening from Sainath agencies, Musheerabad, Hyderabad. Animals were randomly segregated into groups prior to the initiation of the experiment; the rats were acclimatized in polypropylene cage for an episode of 10 days under controlled temperature (26 ± 2 ºC), relative humidity (45-55%) and dark/light cycle for a period of 12 hrs. Rodent pellet diet was supplied and water ad libitum. The institutional animal ethics committee (IAEC) has approved (CPCSEA/IAES/JLS/006/ 01/17/005) the study protocol before the commencement of the experiment.

Acute Toxicity Studies: The acute oral toxicity studies were also performed for the extract according to the OECD guidelines (Organization for Economic Cooperation and Development) 423 on albino rats with little modifications. A limit test dose 2000mg/kg for the rats was considered and it is considered that a dose of 1000mg/kg body weight was considered as safe ¹⁷.

Antihyperglycemic Activity in Albino Wistar Rats: Alloxan induced diabetic model was used to assess the antihyperglycemic property of the methanolic seed extract of Tectona grandis. Animals were kept for fasting 24 h prior to the induction of diabetes. Alloxan monohydrate solution (5%) was administered as a single dose (125 mg/kg bodyweight, I.P.) in normal saline solution to induce diabetes in rats.

Animals with diabetes were divided into five groups (I, II, III, IV, and V), having five rats in each group. The group-I & II served as Normal and diabetic control respectively. Group-III and group-IV (test groups) received 100 mg/kg and 200 mg/kg of methanolic seed extract of Tectona grandis for a period of 15 days and group-V (standard group) received Metformin (5 mg/kg p.o). The blood samples were collected carefully from the tail vein and blood glucose levels were estimated.

RESULTS AND DISCUSSION:

Phytochemical Screening: A range of qualitative phytochemical tests were executed to confirm the presence of glycosides, flavonoids, saponins, proteins, amino acids, carbohydrates, and tannins.

Antihyperglycemic Activity: In the current study, the methanolic seed extract of Tectona grandis was investigated for its antihyperglycemic activity in alloxan-induced diabetic rats. After the induction of diabetes, the rats with diabetes were treated with the extract for 15 days. Results showed that the extract exhibited significant reduction and normalization of blood glucose levels in the diabetic rats when compared to the control Table 1.

The effect is considered significant when compared to the standard drug metformin Fig. 1. The antihyperglycemic activity of the methanolic seed extract of Tectona grandis is in dose-dependent manner Fig. 2. The mechanism of activity may be due to the protective effect of the extract on the islets of Langerhans or regeneration of the alloxan damaged β-cells. Since, the induction of diabetes in group-II is by destructing the β-cells; regular dose of the extract (100 mg/kg and 200 mg/kg per body weight) might have increased the regeneration of the β-cells in group III and IV, which might be the reason for the recovery from the hyperglycemia after 15 days. Presence of various phytochemicals like xanthones, glycosides, flavonoids and saponins may contribute to the protection against diabetes.

TABLE 1: EFFECT OF METHANOLIC SEED EXTRACT OF TECTONA GRANDIS IN ALLOXAN (150 mg/kg, i.p.) INDUCED DIABETIC ALBINO WISTAR RATS DURING 15 DAYS OF TREATMENT

Values are given as mean ± SEM for groups of five animals each *P < 0.01 (graph pad prism) using one-way analysis followed by Tukey's post hoc test. Diabetic control was compared with the normal control and extract treated groups were compared with the diabetic control

FIG. 1: EFFECT OF METHANOLIC SEED EXTRACTS OF TECTONA GRANDIS IN ALLOXAN INDUCED RATS DURING 15 DAYS OF TREATMENT. (* Significantly different from control, # significantly different from diabetes control for specifically mentioned day)

FIG. 2: EFFECT OF METHANOLIC SEED EXTRACT OF TECTONA GRANDIS IN ALLOXAN (150 mg/kg, i.p.) INDUCED DIABETIC ALBINO WISTAR RATS DURING 15 DAYS OF TREATMENT

CONCLUSION: To conclude, the methanolic seed extract of Tectona grandis possesses significant antihyperglycemic activity in adult Wistar rats in a dose-dependent manner. This study is perceptible to have the antidiabetic potential of teak seeds and further investigation is necessary to understand the molecular mechanism involved in the anti-hyperglycemic potential of teak seeds.

ACKNOWLEDGEMENT: Authors are thankful to the Department of Botany, Osmania University for providing necessary facilities.

CONFLICTS OF INTEREST: The authors declare that they have no conflicts of interest.

REFERENCES:

1. Tewari DN: A monograph on Teak (Tectona grandis). Interna Book Distributors Dehra Dun India 1992; 152-63.
2. Nayeem N and Karvekar MD: Isolation of phenolic compounds from the methanolic extract of Tectona grandis. Res J Pharm Biol Chem Sci 2010; 1: 221-25.
3. Ramachandran S and Rajasekaran A: Blood glucose-lowering effect of Tectona grandis flowers in type 2 diabetic rats: a study on identification of active constituents and mechanisms for antidiabetic action. Journal of Diabetes 2014; 6(5): 427-37.
4. Siddiqui MB, Alam MM and Husain W: Traditional treatment of skin diseases in Uttar Pradesh, India Econ Bot 1989; 43: 480-86.
5. Ajayi GO, Olowe JA and Ajuluchukwu JN: Tectona grandis Linn. (Verbenaceae) leaf ethanol extract in renal artery occluded hypertensive rats. Planta Med 2011: 77(12): PM222.
6. Singh PK: Antiulcer activity using ethanolic extract of Tectona grandis root. Int J Pharmacognosy and Phytochem Res 2017; 11(1): 195-06.
7. Krishna MS and Nair JA: Antibacterial, cytotoxic and antioxidant potentials from different extracts of leaves, bark and wood of Tectona grandis. Int J Pharma Sci Drug Res 2010; 2(2): 155-58.
8. Sangeetha K, Purushothaman I and Rajarajan S: Spectral characterisation, antiviral activities, in-silico ADMET and molecular docking of the compounds isolated from Tectona grandis to chikungunya virus. Biomed Pharmacother 2017; 87: 302-10.
9. Giri SP and Varma SB: Analgesic and anti inflammatory activity of Tectona grandis stem extract. J Basic Clin Physiol Pharmacol 2015; 26(5): 479-84.
10. Sumthong P, Damveld RA, Choi YH, Arentshorst M, Ram AF and Hondel VCA: Activity of quinones from teak (Tectona grandis) on fungal cell wall stress. Planta Med 2006; 72: 943-44.
11. Sharma P, Pooja, Samanta KC and Rathore KS: Antipyretic activity of methanolic extract of root of Tectona grandis on albino rats. J Phar Toxicol 2011; 1(2): 28-33.
12. Ghareeb MA: Antioxidant and cytotoxic activities of Tectona grandis leaves Int J of Phytopharmacol 2014; 5(2): 143-57.
13. Rao KV, McBride TJ and Oleson JJ: Recognition and evaluation of lapachol as an antitumor agent. Cancer Res 1968; 28: 1952-54.
14. Jaybhaye D, Varma S, Gagne N, bonde V, Gite A and Bhosle D: Effect of Tectona grandis seeds on hair growth activity of albino mice. Int J Ayurveda Res 2010; 1(4): 211-15.
15. Betancourt BA: Silvicultura especial de árboles maderables tropicales. Havana City, Cuba: Editorial Científico-Técnica 1983, 342-45.
16. Harbone JB: Phytochemical methods: a guide to modern techniques of plant analysis. Chapman and Hall Ltd., London 1973; 279.
17. Dokuparthi SK, Khan MA, Anusha A, Bee M, Shaibaz, Shahajeb S, Sunil Kumar K and Suthakaran R: Acute oral toxicity study of Tectona grandis methanolic seed extract in albino mice. J Phytopharmacol 2017; 6(2): 183-85.
    

    ---

    How to cite this article:

    Rani GJ and Bhavani NL: Antihyperglycemic potential of teak seeds in alloxan induced diabetic rats. Int J Pharm Sci & Res 2020; 11(5): 2169-72. doi: 10.13040/IJPSR.0975-8232.11(5).2169-72.

    ---

    All © 2013 are reserved by the International Journal of Pharmaceutical Sciences and Research. This Journal licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License.

    ---