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RESEARCH ARTICLE
Advanced Science Letters
Vol. 4, 442–448, 2011
A Rapid Scavenger of the Lipid
Peroxidation Product Malondialdehyde:
New Perspective of Taurine
Yan Deng
1 2 ∗
, Nongyue He
1 2
, Lijian Xu
1
, Xiaolong Li
1 2
, Song Li
1
,
Zhiyang Li
2
, and Hongna Liu
2
1
Hunan Key Laboratory of Green Packaging and Biological Nanotechnology,
Hunan University of Technology, Zhuzhou 412008, China
2
State Key Laboratory of Bioelectronics, Southeast University, Nanjing 210096, China
The purpose of this study is to check if taurine, as an antioxidant or dietary supplement, can trap MDA (mal-
ondialdehyde) indirectly or directly and thereby prevents the formation of advanced lipoxidation end products
(ALEs) in vitro. Reaction between taurine with fatty acid, verified by detecting the formation and yield of MDA
and taurine consumption, shows that taurine may trap reactive intermediates during lipid peroxidation. The
direct reaction between taurine and MDA indicates that taurine reacts readily with MDA under supraphysiologi-
cal conditions to form different products. A nonfluorescent enamine (product 1) and a lipofuscin-like fluorescent
1,4-dihydropyridine (product 2) were obtained experimentally from reaction of equimolar of taurine with MDA
and were detected by means of HPLC (high-performance liquid chromatography) separation for the reaction
mixtures at ten minutes and 48 h. It was observed that the former was formed much faster than the latter. We
suggest a mechanism for both the oxidation process of polyunsaturated fatty acids (PUFA) and the reaction of
taurine and MDA. Taurine, as a potent inhibitor of the chemical modification of proteins, also greatly prevents
the formation of lipofuscin-like fluorescence induced by the reaction of MDA with bovine serum albumin. The
results indicate that the scavenging effects of taurine on reactive carbonyl compounds may play an important
role in inhibiting the formation of ALEs and in protecting proteins against carbonyl stress.
Keywords: Lipid Peroxidation, Reactive Carbonyl Compounds, Malondialdehyde (MDA), Taurine,
Scavenging.
1. INTRODUCTION
Tissue deterioration and aging have been widely associated with
the accumulation of chemical processes induced by lipid perox-
idation and glycation,
1 2
which are two critical biological side-
reactions in the energy metabolism and lead to the formation of
advanced glycation end-products (AGEs) and advanced lipoxi-
dation end products (ALEs). These processes have been widely
documented to be responsible for the formation of various age
pigment-like fluorophores and many chronic diseases, such as
chronic inflammatory diseases,
3 4
neuronal degenerative diseases,
and even physiological aging.
5–7
A variety of reactive carbonyl
compounds derived from Maillard and lipid peroxidation reac-
tions act as intermediates in the formation of AGEs and ALEs.
8 9
These carbonyl compounds were found to react readily with an
amino group of proteins giving rise to the formation of pro-
tein aggregates, resulting in protein structural and functional
∗
Author to whom correspondence should be addressed.
alterations.
10 11
Such alterations are now known as “carbonyl tox-
ification” or “carbonyl stress” in the related field.
12
Malondialdehyde (MDA), at the level of 0.3–30 nmol/mL
in human plasma under pathophysiological conditions, can tar-
get a variety of biological components, such as structural and
functional proteins and nucleic acids.
5
MDA reacts with DNA
bases to produce adducts to deoxyguanosine, deoxyadenosine
and deoxycytidine.
13
MDA causes tissue injury and the depres-
sion of energy metabolism, thus representing biochemical mark-
ers for disease progression, such as chronic myeloid leukemia,
14
Huntington’s disease.
15
Recent research results suggest that
schizophrenic patients exhibit increased MDA levels, which lead
to neuronal damage.
16
These findings further support a role of
carbonyl injury in the pathogenesis and the potential benefits of
antioxidant therapy.
Taurine (2-aminoethanesulfonic acid) not only exists in bile but
also widely presents in tissue and cells of all animals, especially,
its content reaches the highest in tissues of halobios. Evidence
suggests a possible role for taurine administration such as retinal
442 Adv. Sci. Lett. Vol. 4, No. 2, 2011 1936-6612/2011/4/442/007 doi:10.1166/asl.2011.1219