Antioxidant and Protective Effects of Major Flavonoids from Teucrium polium on β-Cell Destruction in a Model of Streptozotocin-Induced Diabetes

Abstract

The hypoglycemic effect of Teucrium polium has been accounted for by its constituents that increase insulin release. The present study aimed to investigate whether the major flavonoid compounds (rutin and apigenin) from the methanol extract of Teucrium polium would stimulate insulin secretion and, if so, to further elucidate the mechanism behind this effect. Isolated rat pancreatic islets were batch incubated to study the effect of rutin and apigenin on insulin secretion at various glucose concentrations. Treated islets in the presence of streptozotocin (STZ) and flavonoid compounds significantly increased insulin release by almost 56 % compared with STZ-treated islets. Our data indicated that the flavonoids in T. polium extract appeared to be helpful in protecting pancreatic islets against exposure to STZ in vitro due to their antioxidant activity.

Key words

flavonoids - hypoglycemic - insulin - Lamiaceae - Teucrium polium

References

• 1 Abdollahi M, Karimpour H, Monsef-Esfahani H R. Anti-nociceptive effect of Teucrium polium total extract and essential oil in mouse writhing test.  Pharmacol Res. 2003;  48 31-35
• 2 Rasekh H R, Khoshnood-Mansourkhani M J, Kamalinejad M. Hypolipidemic effect of Teucrium polium in rats.  Fitoterapia. 2001;  72 937-939
• 3 Tarig M, Ageel A M, Al-Yahya M A, Moosa J S, Alsaid M S. Antiinflammatory activity of Teucrium polium.  Int J Tissue React. 1989;  11 185-188
• 4 Esmaeili M A, Yazdanparast R. Hypoglycaemic effects of Teucrium polium: studies with rat pancreatic islets.  J Ethnopharmacol. 2004;  95 27-30
• 5 Yazdanparast R, Esmaeili M A, Ashrafi J H. Teucrium polium extracts pancreatic function of streptozotocin diabetic rats: a histological examination.  Iran Biomed J. 2005;  9 81-85
• 6 Matsuda T, Ferreri K, Todorov I. Silymarin protects pancreatic β-cells against cytokine-mediated toxicity: implication of c-Jun NH₂-terminal kinase and Janus kinase/signal transducer and activator of transcription pathways.  Endocrinology. 2004;  146 175-185
• 7 Blois M S. Antioxidant determination by the use of a stable free radical.  Nature. 1958;  181 1199-1200
• 8 Yang J, Guo J, Yuan J. In vitro antioxidant properties of rutin.  Food Sci Technol. 2008;  41 1060-1066
• 9 Princevijeyasingh J. Protective role of apigenin on the status of lipid peroxidation and antioxidant defense against hepatocarcinogenesis in Wistar albino rats.  Phytomedicine. 2004;  11 309-314
• 10 Heim K E, Tagliaferro A R, Bobilya D J. Flavonoid antioxidant: chemistry, metabolism and structure-activity relationship.  J Nutr Biochem. 2002;  13 572-584
• 11 Rastija V, Medić-Šarić M. QSAR study of antioxidant activity of wine polyphenols.  Eur J Med Chem. 2009;  44 400-408
• 12 Kim M J, Ryu G R, Chung J S, Sim S S, Min D S, Rhie D J, Yoon S H, Hahn S J, Kim M S, Jo H Y. Protective effect of epicatechin against the toxic effect of streptozotocin on rat pancreatic islets: in vivo and in vitro.  Pancreas. 2003;  26 292-299
• 13 Kamalakkannan N, Stanely Mainzen P. Rutin improves the antioxidant status in streptozotocin induced diabetic rats tissues.  Mol Cell Biochem. 2006;  293 211-219
• 14 Misko T P, Schilling R J, Salvemini D, Moore W M, Currie M G. A fluorometric assay for the measurement of nitrite in biological samples.  Analyt Biochem. 1993;  214 11-16
• 15 Rizk A M, Hammuda F M, Rimpler H, Kamel A M. Tridoids and flavonoids of Teucrium polium herb.  Planta Med. 1986;  2 87-88
• 16 Kim M J, Lee K H, Min D S. Distributional patterns of phospholipase C isozymes in rat pancreas.  Pancreas. 2001;  22 47-52