Murine sperm capacitation, oocyte penetration and decondensation following moderate alcohol intake

Abstract

Male chronic alcohol abuse causes testicular failure and infertility. We analyzed the effects of moderate sub-chronic alcohol intake on sperm morphology, capacitation, fertilization and sperm head decondensation. CF-1 male mice were administered 15% ethanol in drinking water for 15 days; control mice received ethanol-free water. Similar patterns of tyrosine phosphorylation were observed in capacitated spermatozoa of control and treated males. Percentage of hyperactivation (H) and spontaneous (SAR) and progesterone-induced (IAR) acrosome reaction significantly decreased at 120 and 150 min of capacitation in treated males compared to controls (H: 14.1 ± 2.5 vs 23.7 ± 2.6, < 0.05; SAR-T120 min: 17.9 ± 2.5 vs 32.9 ± 4.1, < 0.01; IAR-150 min: 43.3 ± 3.5 vs 73.1 ± 1.1, < 0.001, = 6). During fertilization (2.5, 3.5 and 4.5 h post-insemination), there was an increased percentage of fertilized oocytes (with a decondensed sperm head and one or two pronuclei) in treated males ( < 0.001, = 7). After 60 min of decondensation with glutathione plus heparin, the percentage of decondensed sperm heads was significantly higher in treated males than in controls (mean ± s.d.: 57.1 ± 5.6 vs 48.3 ± 4.5, < 0.05, = 5). The percentage of morphologically normal sperm heads was significantly decreased in treated males with respect to controls ( < 0.001, = 9). These results show that short-term moderate alcohol consumption in outbred mice affect sperm morphology, hyperactivation, acrosomal exocytosis, and the dynamics of fertilization and sperm nuclear decondensation.

Impact of Alcohol Consumption on Male Fertility Potential: A Narrative Review

“…Besides the alterations in the semen quality (lower sperm concentration, motility, and percentage of normal forms), Rahimipour et al also reported reduced DNA condensation and integrity in mice fed with ethanol compared to controls, along with increased apoptotic rates [ 85 ]. In addition, in vitro experiments showed an accelerated acrosomal loss occurring during the sperm capacitation of human and animal sperm incubated in ethanol, further reducing their fertilizing ability [ 124 , 125 , 126 , 127 ]. This is probably due to the capacity of ethanol to alter lipid fluidity and membrane permeability through the oxidation of the membranes’ lipids and proteins [ 127 ].…”

“…In addition, in vitro experiments showed an accelerated acrosomal loss occurring during the sperm capacitation of human and animal sperm incubated in ethanol, further reducing their fertilizing ability [ 124 , 125 , 126 , 127 ]. This is probably due to the capacity of ethanol to alter lipid fluidity and membrane permeability through the oxidation of the membranes’ lipids and proteins [ 127 ]. In rats, decreased sperm motility was observed after exposure to EtOH, as well as changes in the meiotic divisions, reduced gametes viability, and a higher rate of sperm with poorly condensed chromatin [ 86 , 87 ].…”

Insights into the adverse effects of prepubertal chronic ethanol exposure on adult female reproduction

“…Alcohol exposure has adverse effects on the reproductive system of females and males [ 22 , 23 ], and can also cause abnormal preimplantation embryo development. In our current society, more and more preadolescent women are inevitably exposed to alcohol [ 24 ].…”

Discovery of the First Human Arylsulfatase A Reversible Inhibitor Impairing Mouse Oocyte Fertilization

“…At the end of the incubation period, the oocytes were fixed in 2% PFA diluted in CMF-PVP 0.4% and were then stained with 0.1 mM Hoechst 33342 in the dark for 20 min at RT. After washing, oocytes were examined under phase contrast and fluorescence microscopy (Axioplan Zeiss) and were classified as described in Sanchez et al and Rosenbusch et al − …”