Mass Spectrometric Detection of Cholesterol Oxidation in Bovine Sperm
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Author
Brouwers, Jos F.
Boerke, Arjan
Silva, Patrícia F.N.
Garcia-Gil, Nuria
van Gestel, Renske A.
Helms, J. Bernd
van de Lest, Chris H.A.
Gadella, Bart M.
Publication date
2011-07-01ISSN
0006-3363
Abstract
We report on the presence and formation of cholesterol
oxidation products (oxysterols) in bovine sperm. Although
cholesterol is the most abundant molecule in the membrane of
mammalian cells and is easily oxidized, this is the first report on
cholesterol oxidation in sperm membranes as investigated by
state-of-the-art liquid chromatographic and mass spectrometric
methods. First, oxysterols are already present in fresh semen
samples, showing that lipid peroxidation is part of normal sperm
physiology. After chromatographic separation (by high-performance liquid chromatography), the detected oxysterol species
were identified with atmospheric pressure chemical ionization
mass spectrometry in multiple-reaction-monitoring mode that
enabled detection in a broad and linear concentration range
(0.05–100 pmol for each oxysterol species detected). Second,
exposure of living sperm cells to oxidative stress does not result
in the same level and composition of oxysterol species compared
with oxidative stress imposed on reconstituted vesicles from
protein-free sperm lipid extracts. This suggests that living sperm
cells protect themselves against elevated oxysterol formation.
Third, sperm capacitation induces the formation of oxysterols,
and these formed oxysterols are almost completely depleted
from the sperm surface by albumin. Fourth, and most
importantly, capacitation after freezing/thawing of sperm fails
to induce both the formation of oxysterols and the subsequent
albumin-dependent depletion of oxysterols from the sperm
surface. The possible physiological relevance of capacitationdependent oxysterol formation and depletion at the sperm
surface as well as the omission of this after freezing/thawing
semen is discussed.
Document Type
Article
Document version
Published version
Language
English
Subject (CDU)
663/664 - Food and nutrition. Enology. Oils. Fat
Pages
9
Publisher
Oxford University Press
Is part of
Biology of Reproduction
Citation
Brouwers, Jos F., Arjan Boerke, Patrícia F.N. Silva, Nuria Garcia-Gil, Renske A. Van Gestel, J. Bernd Helms, Chris H.A. Van De Lest, and Bart M. Gadella. 2011. “Mass Spectrometric Detection of Cholesterol Oxidation in Bovine Sperm.” Biology of Reproduction 85 (1): 128–136. doi:10.1095/biolreprod.111.091207
Grant agreement number
MEC/ /EX2005-0460/ES/ /
Program
Qualitat i Tecnologia Alimentària
This item appears in the following Collection(s)
- ARTICLES CIENTÍFICS [2694]
Except where otherwise noted, this item's license is described as http://creativecommons.org/licenses/by-nc/4.0/