Biochemical characterization and membrane fluidity of membranous vesicles isolated from boar seminal plasma

Boar seminal plasma exosomes: Effect on sperm function and protein identification by sequencing

“…Lipid vesicles with a composition similar to seminal plasma vesicles (645 mM cholesterol, 138 mM sphingomyelin, 110 mM di-palmitoylphosphatidylethanolamine, 57 mM di-palmitoylphosphatidylcholine, and 28 mM di-palmitoylphosphatidylserine) were prepared [16]. Stock solutions of each lipid (5 times concentrated in chloroform:methanol 2:1) were mixed in equal parts.…”

“…Membrane fluidity was estimated by the order parameter S, which was calculated using the hyperfine constant values measured from the ESR spectrum (A // and A t ). Calculations and the correction of the A t value were performed as described [16]. The S parameter provides a measure of the degree of structural order in the membrane: an S value of 1 represents a rapid spin-label motion restricted to one axis, and S ¼ 0 indicates a fast isotropic motion, i.e., maximum freedom.…”

“…Prostasomes, the membrane vesicles secreted by the human prostate, have been more extensively studied [20]. In addition, similar vesicles have also been isolated from the seminal plasma of rat, rabbit, ram, bull, stallion, and boar [16,18,[21][22][23][24]. Because prostasomes have immunosuppressive, antioxidant, and antibacterial properties, it has been suggested that they are involved in several biological processes which can indirectly influence sperm function [20].…”

“…Mammalian seminal plasma contains membranous vesicles (exosomes) characterized by a high cholesterol and sphingomyelin content, and a complex protein composition [14][15][16][17][18]. These vesicles are produced by the epididymis and the prostate [19].…”

In vitro effect of aluminium upon erythrocyte membrane properties

“…1). S gives a measure of the degree of structural order in the membrane and was calculated as described in [33], using the following expression:…”