Cholesterol-loaded cyclodextrin pretreatment of ram spermatozoa protects structural integrity of plasma membrane during osmotic challenge and reduces their ability to undergo acrosome reaction in vitro

Protective effect of cholesterol-loaded cyclodextrin pretreatment against hydrogen peroxide induced oxidative damage in ram sperm

“…Moreover, it has been stated that cholesterol directly modulates the physical properties of lipid bilayer and alter the membrane response to the degenerative processes including lipid peroxidation in different biological systems [31,23,25]. Until now enhanced osmotic tolerance, membrane fluidity and reduced cryocapacitation/premature acrosome reaction are the outcomes of CLC which are considered/proposed as possible reasons behind improved cryosurvival rate of CLC treated sperm [2,3,12,24,36,45]. However, a thorough mechanism of action of CLC in improving sperm quality has not been addressed yet.…”

“…Sperm viability was assessed by using eosin-nigrosin staining whereas, plasma membrane integrity was determined by using hypo-osmotic swelling (HOS) test combined with eosin staining (HE-test). The sperm with reacted acrosome were determined through Coomassie Blue G-250 staining as reported earlier [2].…”

“…The exact mechanism of action of CLC, involved in sperm protection during freezing and thawing procedure is not well understood. However, its role in enhancing osmotic tolerance and reducing premature capacitation/acrosome reaction have been elucidated in simulation studies in different species [2,3,12,24,45,36].…”

Effect of environmental heat stress on Kıvırcık ram sperm parameters

“…Acrosome reacted sperm rate was determined with a Coomassie Blue G-250 staining procedure (Ahmad et al, 2013) in fresh semen, at 0 min after 1 h incubation period, 20, 40 and 60 min after lysophosphatidylcholine (LPC) treatment, respectively. In fresh semen, a 15 μl sperm sample was directly fixed.…”

Effect of cyclodextrins, cholesterol and vitamin E and their complexation on cryopreserved epididymal ram semen

“…In Ram particularly, cyclodextrins-cholesterol complex has been reported to improve motility, viability and membrane integrity (Ahmad et al, 2013;Awad, 2011;Mocé et al, 2010;Motamedi-Mojdehi et al, 2014). Cyclodextrins are oligosaccharides with an internal hydrophobic cavity which forms inclusion complexes with various hydrophobic guest molecules, including cholesterol and lipophilic vitamins, and an external hydrophilic face increasing their solubility in semen extenders (Dodziuk, 2006;López-Nicolás et al, 2012).…”