ARS | Publication request: Cinnamon Polyphenols Attenuate Neuronal Death and Glial Swelling in Ischemic Injury

Submitted to: Society for Neuroscience Abstracts and Proceedings
Publication Type: Proceedings/Symposium
Publication Acceptance Date: December 10, 2007
Publication Date: January 30, 2008
Citation: Panickar, K.S., Polansky, M.M., Anderson, R.A. 2008. Cinnamon Polyphenols Attenuate Neuronal Death and Glial Swelling in Ischemic Injury. Society for Neuroscience Abstracts and Proceedings. 380.18.

Technical Abstract: Brain edema is a major complication associated with ischemic stroke and is characterized by a volumetric enlargement of the brain. Astrocyte swelling is a major component of brain edema. We investigated the protective effects of polyphenols isolated from green tea and cinnamon in C6 glial cultures subjected to 5 hr oxygen-glucose deprivation (OGD), an in vitro model of ischemic injury. Cell volume was determined using the 3-O-methyl-[3H]-glucose method. Ninety minutes after the end of OGD, cell volume increased by 35% when compared with controls which was blocked by green tea (0.1 mg/ml) and an aqueous extract of cinnamon (0.1 mg/ml). Individual components of either green tea (EGCG, caffeine, catechin and epicatechin) or cinnamon (dimer, coumarin) did not protect. Likewise, resveratrol (10-100 µM), a polyphenolic anti-oxidant found generally in grapes and blueberries, did not prevent swelling. Mitochondrial dysfunction, a key feature of ischemic injury, plays an important role in glial swelling. Depolarization of the mitochondrial membrane potential (MMP) was assessed immediately at the end of OGD using TMRE, a fluorescent dye. OGD-induced depolarization of the MMP was attenuated by both green tea and cinnamon. One possible mechanism by which extracts from tea and cinnamon attenuate glial swelling may be through preventing mitochondrial dysfunction. (Funded by USDA/ARS and Diabetes Action Foundation).