Antioxidative Activity of Green Tea Polyphenol in Cholesterol-Fed Rats

Abstract

This study investigated the effects of green tea polyphenol on the serum antioxidative activity and cholesterol levels of cholesterol-fed rats and compared them with those of probucol, an antioxidant hypocholesterolemic agent. To evaluate the antioxidative activity, the susceptibility to oxidative modification of low-density lipoprotein (LDL) isolated from the serum of cholesterol-fed rats was measured, as was the serum antioxidative activity using the spontaneous autoxidation system of brain homogenate. Administration of green tea polyphenol effectively inhibited LDL oxidation and elevated serum antioxidative activity to the same degree as probucol. However, higher amounts of polyphenol than probucol needed to be administered to reduce the total, free, and LDL cholesterol levels. Furthermore, green tea polyphenol increased the levels of high-density lipoprotein (HDL) cholesterol, leading to dose-dependent improvement of the atherogenic index, an effect that was not seen with probucol. Thus, green tea polyphenol may exert an antiatherosclerotic action by virtue of its antioxidant properties and by increasing HDL cholesterol levels.

Influence of Amla (Emblica officinalis Gaertn.) on Hypercholesterolemia and Lipid Peroxidation in Cholesterol-Fed Rats

“…We have previ ously reported that the plant food-derived ingredient, polyphenol, also acts as a hypocholesterolemic agent and has an inhibitory effect on oxidized LDL (41). In our present study, EtOAc extract of amla, a flavonoid rich fraction, exhibited stronger protective activities on LDL oxidation and hypercholesterolemia than Sun Amla.…”

Protictive effects of green tea and garlic on the morphological and oxidative stress changes of hippocampus in aged male and female albino rats

“…The previous studies of [33,34] reported that GT reduces oxidative stress by virtue of its antioxidant properties thus improving the structural integrity of cell membrane and eventually alleviates the histopathological changes as well as the biochemical perturbations. These results suggest that catechins, epicatechin (EC), epigallocatechin (EGC), epicatechin-3-gallate (ECG), and EGCG could have a direct (antioxidant) or indirect (increase of activity or expression) effect [35,36].…”

Comparative studies on the physicochemical and antioxidant properties of different tea extracts

“…It was a complex mixture containing multiple compounds from simple phenolics, catechins to polysaccharides and complex thearubigins, many of which had been reported to have health functions such as antiallergic (Suzuki et al 2000), antioxidative (Jhoo et al 2005), antimutagenic and anticarcinogenic (Standley et al 2001), antiatherosclerotic (Yokozawa et al 2002), antibacterial (Yildirim et al 2000), and hypoglycemic (Zhou et al 2007) activities.…”