TITLE:
A review: Oxidative stress and its role in reproduction
AUTHORS:
Galina Nenkova, Albena Alexandrova
KEYWORDS:
Antioxidants; Assisted Reproductive Technology; Reactive Oxygen Species; Sperm
JOURNAL NAME:
Advances in Bioscience and Biotechnology,
Vol.4 No.1,
January
21,
2013
ABSTRACT: Recently
the problem of infertility has become more acute. About 3% - 7% of couples
suffer a lasting infertility problem and there is a tendency of constant
increasing of this number. Existing data reveal that in many of the infertility
cases, the cause of sterility is the disabled sperm as a result of the
oxidative stress (OS). There are several sources of reactive oxygen species
(ROS) in the sperm. Both enzymatic and nonenzymatic antioxidants act as a
counteraction against ROS production in seminal plasma. However due to the
limited cytoplasm, the spermatozoa are more susceptible to oxidative damage
because of the lack of protective cytoplasmic antioxidant enzymes. Currently,
many couples suffering fertility problems resort to assisted reproductive
technology (ART). Unfortunately, the success rate of ART is relatively low—about
30%. Sperm processing incl. centrifugation, freezing and thawing is associated
with the generation of ROS. A range of strategies for sperm prevention of OS
are developed. Many studies concern antioxidants and their impact on sperm
function, but there are a lot of contradictions in terms of doses and types of
combinations that can be used in ART. Future studies should aim the creation of
standard and reliable operating procedures for increasing the successfulness of
these techniques. This
paper offers an overview of the impact of OS on the reproduction, pointing out
the sources of ROS in the sperm, the antioxidant defense systems, and the
strategies for prevention and improvement of the sperm reproductive
functions, incl. those applied in ART.