Antioxidant and DNA Protection Effects of Taurine by Electron Spin Resonance Spectroscopy - Advances in Experimental Medicine and Biology - page 156

hydroxyl radicals, superoxide radicals, and alkyl radicals. Findings from this study sug-
gest that taurine may be a useful radical scavenger and a potential supplement for the
food, pharmaceutical, and cosmetic industries as well as feed and/or antibiotic because
of its potent antioxidant capacities against various reactive radicals.

Abbreviations

DPPH 1,1-Diphenyl-2-picrylhydrazyl

ESR Electron spin resonance

17.1 Introduction

Taurine (2-aminoethanesulfonic acid) is a sulfur-containing b -amino acid which is found
in all animal cells at millimolar concentration (Oliveira et al. 2010 ) . Previous studies have
shown that taurine possesses several biological functions, such as bile acid conjugation,
maintenance of calcium homeostasis, osmoregulation, membrane stabilization, and
antidiabetic, antihypertensive, antioxidant, and hepatoprotective activities (Huxtable
1992 ; Pushpakiran et al. 2005 ; Liu et al. 2008 ). One of the possible mechanisms of its
pharmacological action involves the free radical scavenging activity (Tabassum et al.
2006 ). Taurine has been widely used to rescue oxidative stress and as a neuroprotective
agent in disparate models (Shuaib 2003 ; El Idrissi 2006 ). Taurine is also known to react
with and detoxify hypochlorous acid (HOCl) generated by activated neutrophils from
myeloperoxidase (MPO), hydrogen peroxide, and chloride during the oxidative burst,
and this protective action involves the formation of stable taurine chloramines
(Cunningham et al. 1998 ). Moreover, it has been reported that taurine has potential free
radical scavenging activities against many oxygen-derived radicals (Aruoma et al. 1988 ;
Shi et al. 1997 ). Nonetheless, there is no conclusive evidence that taurine regulates the
levels of the antioxidant defense system and the mechanism on the antioxidant activity of
taurine. The objective of the present study was to examine the in vitro DNA protective
activity and antioxidant properties of taurine against different reactive species at various
concentrations using a spin-trapping electron method.

17.2 Methods

17.2.1 Reagents

5,5-Dimethyl-1-pyrroline N -oxide (DMPO), 2,2-azobis(2-amidinopropane) hydrochloride
(AAPH), 1,1-diphenyl-2-picrylhydrazyl (DPPH), and alpha -(4-pyridyl-1-oxide)- N - tert -
butylnitrone (4-POBN) were obtained from Sigma Chemical Co. (St. Louis, MO, USA).
All other reagents were of the highest grade available commercially.