n-oleoylethanolamine and laurdan

N-acylethanolamides are naturally occurring hydrophobic molecules usually present in a very small amount in many mammalian tissues and cells. The presence of N-acylethanolamides has also been demonstrated in human reproductive tracts and fluids, although their biological effects and molecular mechanisms of action are not yet completely elucidated. It is known that some N-acylethanolamides, such as oleoylethanolamide, have antioxidative properties. The aim of this study was to test whether oleoylethanolamide could protect sperm cells from reactive oxygen species-induced oxidative damage in cases of idiopathic infertility, because the excessive generation of these radicals was associated with this pathology. Our results show that 2.5 nM oleoylethanolamide in vitro supplementation significantly reduces DNA strand breaks both in fertile and infertile subjects. Moreover, oleoylethanolamide increases kinematic parameters, such as curvilinear velocity and amplitude of lateral head displacement and hyperactivation, both in the presence and in the absence of oxidative stress. Results of this study support the hypothesis of a possible protective action of oleoylethanolamide against reactive oxygen species, which could explain its beneficial effects on in vitro capacitated spermatozoa.

Topics: 2-Naphthylamine; Adult; Cell Membrane; Comet Assay; DNA Damage; Endocannabinoids; Female; Humans; Hydrogen Peroxide; Infertility, Male; Laurates; Male; Oleic Acids; Oxidative Stress; Semen; Spectrometry, Fluorescence; Sperm Capacitation; Spermatozoa

The effect of N-lauroylethanolamine (N-LEA) and N-oleoylethanolamine (N-OEA) on the thermal behaviour of fully hydrated egg phosphatidylethanolamine (TPE) was investigated by the steady-state fluorescence of 2-dimethylamino-(6-lauroyl)-naphtalene (laurdan) and 1-(4-trimethylaminophenyl)-6-phenyl-1,3,5-hexatriene (TMA-DPH). The parameter generalised polarisation (GP), calculated by exciting laurdan at 340 and 410 nm, revealed the gel to liquid crystalline lamellar (L alpha) as well as the L alpha to inverse hexagonal (HII) phase transitions of TPE. The L alpha to HII phase transition was not detected in TPE/N-OEA system, probably because of the formation of an intermediate Q224 cubic phase. The formation of Q224 phase in TPE/N-OEA and TPE/N-LEA systems was previously demonstrated by X-ray diffraction, but neither laurdan generalised polarisation nor TMA-DPH steady-state fluorescence anisotropy measurements revealed the presence of this phase. It is suggested that the lack of detection of the cubic phase is probably due to the similarity in dynamic characteristics and hydration levels of phospholipid headgroups in the bilayer and cubic phases.

Topics: 2-Naphthylamine; Diphenylhexatriene; Endocannabinoids; Ethanolamines; Fluorescence Polarization; Fluorescent Dyes; Laurates; Lauric Acids; Oleic Acids; Phosphatidylethanolamines