Submitted to: Journal of Agricultural and Food Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: January 31, 2011
Publication Date: February 17, 2011
Citation: Cao, H., Anderson, R.A. 2011. Cinnamon polyphenol extract regulates tristetraprolin and related gene expression in mouse adipocytes. Journal of Agricultural Food & Chemistry. 59(6):2739-2744. Interpretive Summary: Bioactive plant products have been used for the prevention and treatment of various diseases since the ancient history. One of the major classes of bioactive compounds is plant polyphenols, which are found in seeds, fruits, leaves, and bark. These compounds are widely present in the diet and are potentially important for human health. Cinnamon is proposed to be effective in the prevention and treatment of obesity and diabetes. Multiple studies provide evidence for supporting the proposal that cinnamon extract has insulin-like activity in cells, animals, and people with type 2 diabetes. However, some studies do not report positive effects of cinnamon in diabetic patients. Clearly, more basic studies are needed for better understanding the health benefits of cinnamon and its derived compounds. We investigated the effects of cinnamon extract on gene expression in cultured mouse fat cells. Our results indicate that cinnamon extract regulates a number of genes in fat cells and suggest that the health benefits of cinnamon are due to its insulin-like effects as well as other effects.
Technical Abstract: Cinnamon (Cinnamomum verum) has been widely used in spices, flavoring agents, and preservatives. Cinnamon polyphenol extract (CPE) may be important in the alleviation of chronic diseases, but the molecular evidence is not substantial. Tristetraprolin (TTP) family proteins have anti-inflammatory effects by destabilizing pro-inflammatory mRNAs. TTP expression is reduced in fat cells of obese people with metabolic syndrome and in brain tissue of suicide victims. This study used quantitative real-time PCR to explore the effects of CPE on the regulation of TTP, vascular endothelial growth factor (VEGF), and expression of related genes in mouse 3T3-L1 adipocytes. CPE (100 µg/ml) increased TTP mRNA levels by up to 10-fold, and its stimulation was sustained over 16 h. The levels of VEGF mRNA, a putative target of TTP, were decreased 40-50% by CPE. It also affected the expression of other genes coding for ZFP36L and ZFP36L3 (TTP homologues), GM-CSF, COX2, IL6, APP, G-CSF, and PAI1. This study demonstrated that CPE rapidly induces TTP mRNA, reduces VEGF mRNA, and affects the expression of a number of other genes in the cultured adipocytes.