Effects Of Vitamin E And Tea On Iron Induced Lipid Peroxidation And Free Radical Metabolizing Enzymes In The Rat Brain.

Author

Resni Mona 

Date

2002

Keyword

tea, antioxidant, vitamin E, lipid peroxidation, free radical

Abstract

A study on the antioxidant effects of vitamin E, Green Tea and Black Tea was made by looking at their effect on lipid peroxidation induced by iron and on the activity of free radical metabolizing enzymes in the rat brain. The extent of lipid peroxidation was monitored by observing the accumulation of malondialdehyde (MDA) in the rat brain sample. The enzymes studied were superoxide dismutase (SOD), glutathione peroxidase (GP) and xanthine oxidase (XOD). Both in vitro and in vivo studies were carried out. In the in vitro studies, all the three substances ie Vitamin E, Green Tea and Black Tea were able to reduce significantly the level of MDA. The activity of SOD and GP was enhanced when rat brain supernatant was incubated with Green Tea and Black Tea. Similar effect was not seen with vitamin E within the range tested. However, all these substances was unable to exert any effect on the activity of xanthine oxidase within the range tested . In vivo study suggest that both Green Tea and Black Tea were able to protect the brain against iron induced lipid peroxidation in vivo but no effects were observed on the activities of SOD, GP and XOD. High Performance Liquid Chromatographic (HPLC) analysis with Photo Diode Array Detector (PDA) of the 4 major polyphenols i.e (-) epigallocatechin gallate(EGCG); (-) epicatechin gallate(ECG); (-)epigallocatechin( EGC) and (-) epicatechin (ECG) in Tea .showed that Green Tea contains far greater amounts of these compounds as to Malaysian Cameron Tea.