Submitted to: BARC Poster Day
Publication Type: Abstract Only
Publication Acceptance Date: 4/9/2006
Publication Date: 4/15/2006
Citation: Kelly, M.A., Cao, H., Schoene, N.W., Anderson, R.A. 2006. Mechanisms for increased glucose transport in 3t3-l1 adipocytes treated with an aqueous cinnamon extract. (abstract) BARC Poster Day.
Technical Abstract: Dietary factors play a major role in the development of type 2 diabetes mellitus. We have shown previously that a water-soluble extract from cinnamon can improve serum levels of glucose and lipids in people with type 2 diabetes and increase insulin activity in isolated fat cells from rats. In addition, cinnamon extract (CE) increases insulin-stimulated glucose transport in 3T3-L1 adipocytes. The objective of this study was to investigate possible cellular mechanisms of CE on glucose metabolism. We confirmed the effects of CE on insulin stimulated glucose transport in 3T3 cells using 2-deoxy-D-[14C] Glucose. Cells treated with CE had a 3-fold increase in insulin-stimulated glucose transport over untreated cells. The cinnamon extract inhibited the activity of pure protein tyrosine phosphatase (PTP-1B) by over 50% in a dose dependent manner. Western blot analysis revealed that 3T3-L1 cells treated with insulin as well as the CE have increased levels of the insulin dependent GLUT-4 protein and insulin receptor beta. These results suggest that CE, like insulin, has effects on important cellular targets in the insulin signaling pathway, leading to increased glucose metabolism. The CE improves the uptake and utilization of glucose by increasing the efficiency of insulin. This study reveals specific biochemical effects of cinnamon and offers some insight on possible uses of cinnamon products for the alleviation and prevention of type 2 diabetes.