Showing papers on "Sperm plasma membrane published in 2021"
TL;DR: In this article, the effects of phospholipid, neutral lipid and glycolipid homeostasis on sperm fertilization function and male fertility in mammals were reviewed. But, the authors did not consider the effect of sperm motility and capacitation on male fertility.
Abstract: Sperm plasma membrane lipids are essential for the function and integrity of mammalian spermatozoa. Various lipid types are involved in each key step within the fertilization process in their own yet coordinated way. The balance between lipid metabolism is tightly regulated to ensure physiological cellular processes, especially referring to crucial steps such as sperm motility, capacitation, acrosome reaction or fusion. At the same time, it has been shown that male reproductive function depends on the homeostasis of sperm lipids. Here, we review the effects of phospholipid, neutral lipid and glycolipid homeostasis on sperm fertilization function and male fertility in mammals.
16 citations
TL;DR: In this article, the authors investigated the functional impact of in vitro exposure of pig spermatozoa to low concentrations of Roundup® Ultra Plus (RUP), similar to those present as environment contaminants, to its active ingredient glyphosate, and to the non-active component, surfactant polyoxyethyleneamine (POEA).
9 citations
TL;DR: The sperm membrane is composed of a complex mixture of lipids including phospholipids, glycolipids and sterols as discussed by the authors, which is important in modulating many sperm functions.
8 citations
TL;DR: In this paper, the authors investigated whether the presence of AST protected boar sperm from reactive oxygen species (ROS) during the cryopreservation process and found that the addition of AST, especially at a concentration of 2μM, exerted positive effects on post-thaw sperm motility parameters.
8 citations
TL;DR: In this article, the authors determine the PRSS37 interactome by GFP immunoprecipitation coupled with mass spectrometry in PRSS 37-EGFP knock-in mice.
Abstract: A disintegrin and metalloproteinase 3 (ADAM3) is a sperm membrane protein critical for sperm migration from the uterus into the oviduct and sperm-egg binding in mice. Disruption of PRSS37 results in male infertility concurrent with the absence of mature ADAM3 from cauda epididymal sperm. However, how PRSS37 modulates ADAM3 maturation remains largely unclear. Here, we determine the PRSS37 interactome by GFP immunoprecipitation coupled with mass spectrometry in PRSS37-EGFP knock-in mice. Three molecular chaperones (CLGN, CALR3 and PDILT) and three ADAM proteins (ADAM2, ADAM6B and ADAM4) were identified to be interacting with PRSS37. Coincidently, five of them (except ADAM4) have been reported to interact with ADAM3 precursor and regulate its maturation. We further demonstrated that PRSS37 also interacts directly with ADAM3 precursor and its deficiency impedes the association between PDILT and ADAM3. This could contribute to improper translocation of ADAM3 to the germ cell surface, leading to ADAM3 loss in PRSS37-null mature sperm. The understanding of the maturation mechanisms of pivotal sperm plasma membrane proteins will pave the way toward novel strategies for contraception and the treatment of unexplained male infertility.
8 citations
11 Feb 2021
TL;DR: In this paper, the authors compared two different types of soybean lecithin, with egg yolk as a control, and found that the results showed that the protein-free alternative to the egg-yolk for semen cryopreservation was superior.
Abstract: Egg yolk is widely used as a cryoprotectant in dog semen extenders, but there is a risk of contamination with animal pathogens. In addition, egg yolk may vary in composition, making it difficult to standardize the extender. Lecithin is an animal protein-free alternative to egg yolk for semen cryopreservation. Recently, it was shown that 1% of soybean lecithin type II-S was better than 2% for freezing canine semen. The aim of the study was to compare two different types of soybean lecithin, with egg yolk as a control. Ejaculates from eight dogs were divided into three equal parts and diluted with a Tris-based extender, containing either 20% egg yolk, 1% soybean lecithin Type II-S or 1% soybean lecithin Type IV-S. The samples were then frozen. Sperm motility was evaluated by computer-assisted sperm analysis (CASA), acrosome integrity (FITC-PNA/PI) and sperm membrane integrity (SYBR-14/PI) post-thaw, as well as after 2 and 4 hr incubation at 37 degrees C. Post-thaw sperm chromatin structure assay and plasma membrane integrity were evaluated by flow cytometry. Total motility, sperm plasma membrane integrity and acrosome integrity were significantly better in the egg yolk extender than in the two soybean lecithin-based extenders. Individual motility post-thaw differed more than in the fresh samples, illustrating individual differences in tolerance to the cryostress. The DNA Fragmentation Index (% DFI) was significantly lower in the Tris egg yolk (TEY) extender compared to any of the soybean-based extenders. The number of high green stained spermatozoa were significantly higher in Type IV-S compared to the control TEY extender. In conclusion, egg yolk was superior to the two lecithin-based extenders to cryopreserve canine semen.
7 citations
TL;DR: Wang et al. as mentioned in this paper showed that adding 2mmol/l glutathione to the semen diluent can improve the quality of frozen Guanzhong dairy goat sperm, and the sperm viability, plasma membrane intact rate and acrosome intact rate were the highest after thawing.
Abstract: In the process of cryopreservation of dairy goat semen, it will face many threats such as oxidative damage, which will affect the motility and plasma membrane function of sperm. As an endogenous antioxidant in animals, glutathione(GSH) can significantly improve the quality of thawed sperm when added to the frozen diluent of semen of pigs and cattle. In this study, different concentration gradients of GSH[0mmol/L(control), 1mmol/L, 2mmol/L, 3mmol/L, 4mmol/L] were added to the frozen diluent of Guanzhong dairy goat semen. By detecting the sperm motility parameters, acrosome intact rate and plasma membrane intact rate after thawing, the effect of GSH on the cryopreservation of dairy goat semen was explored. Sperm motility parameters were measured with the computer-aided sperm analysis(CASA) system (total power, TM; forward power, PM; linearity, LIN; average path speed, VAP; straight line speed, VSL; curve speed, VCL; beat cross frequency, BCF.). The sperm acrosome integrity rate after thawing was detected by a specific fluorescent probe (isothiocyanate-la beled peanut agglutinin, FITC-PNA), and the sperm plasma membrane integrity rate after thawing was detected by the hypotonic sperm swelling (HOST) method. Reactive oxygen species (ROS) kit, malondialdehyde (MDA) kit, superoxide dismutase (SOD) kit, glutathione peroxidase (GSH-PX) kit were used to detect various antioxidant indicators of thawed sperm. In vitro fertilization experiment was used to verify the effect of adding glutathione on sperm fertilization and embryo development. The results showed that when the concentration of glutathione was 2mmol/l, the sperm viability, plasma membrane intact rate and acrosome intact rate were the highest after thawing, reaching 62.14%, 37.62% and 70.87% respectively, and they were all significantly higher. In terms of antioxidant indexes; the values of SOD and GSH-PX were 212.60 U/mL and 125.04 U/L respectively, which were significantly higher than those of the control group; The values of ROS and MDA were 363.05 U/mL and 7. 02 nmol/L respectively, which were significantly lower than the control group. The addition of 2mmol/L glutathione significantly improves the fertilization ability of sperm. In short, adding 2mmol/l glutathione to the semen diluent can improve the quality of frozen Guanzhong dairy goat sperm.
6 citations
TL;DR: In this paper, the authors examined sperm quality in a cohort of city policemen living and working in Ostrava, Czech Republic at the end of a period with high concentrations of air pollutants (winter) and in the same cohort at the beginning of a relatively low exposure period (summer) and found that sperm DNA damage and the percentage of immature sperm were highly sensitive to air pollution.
5 citations
TL;DR: In this paper, the authors compared oxidative stress markers and vitamin D in male subjects with normal and altered sperm parameters and explored association of these markers: 4-Hydroxynonenal and 3-Nitrotyrosine with Vitamin D.
Abstract: Spermatozoa are vulnerable to oxidative stress because of their inherent reduced antioxidant defence and DNA repair mechanisms. Polyunsaturated fatty acids in sperm plasma membrane break down to cytotoxic lipid aldehyde, 4-Hydroxynonenal, whereas 3-Nitrotyrosine is generated by peroxynitrite induced tyrosine nitration. Both oxidative stress markers contribute to altered sperm function and infertility. Vitamin D, a membrane antioxidant, has a potential scavenger capacity. We compared oxidative stress markers and vitamin D in male subjects with normal and altered sperm parameters and explored association of these markers: 4-Hydroxynonenal and 3-Nitrotyrosine with Vitamin D. Higher 4-Hydroxynonenal levels in altered sperm parameter group and a negative correlation with sperm count, motility and morphology (p < 0.001) was observed. Vitamin D serum concentration in altered sperm parameters was less (p = 0.016) showing a significant positive correlation with sperm count and morphology. 4-Hydroxynonenal was significantly higher in altered sperm parameters showing negative correlation with vitamin D. Highest serum concentrations of 4-Hydroxynonenal were observed in vitamin D-deficient subjects. Significantly higher concentration of 4-Hydroxynonenal was estimated in altered sperm parameters of vitamin D sufficient group (p < 0.001). This suggests 4-Hydroxynonenal as an oxidative stress marker leading to altered sperm function and infertility with some association with vitamin D; needs to be explored.
4 citations
TL;DR: In this paper, a review of the current understanding of the interactions stallion spermatozoa undergo during passage through the female genital tract, and related specific molecular changes that occur at the sperm plasma membrane is provided.
4 citations
TL;DR: In this paper, the suitability of a cholesterol-cyclodextrin semen extender, without inclusion of egg yolk, for cryopreservation of bull semen was determined.
TL;DR: In this paper, a major FnII protein has been identified and isolated from donkey (Equus hemionus) seminal plasma, which they refer to as D onkey S eminal P lasma protein-1 (DSP-1).
TL;DR: In this paper, the chemical lipid composition of the sperm plasma and acrosomal membranes of the saltwater crocodile Crocodylus porosus has been analyzed to provide new insights into sperm physiology, particularly that associated with their preservation ex vivo.
Abstract: This study describes the chemical lipid composition of the sperm plasma and acrosomal membranes of the saltwater crocodile Crocodylus porosus with the aim of providing new insights into sperm physiology, particularly that associated with their preservation ex vivo. The specific fatty acid composition of the sperm plasma and acrosomal membranes is documented. The mean (± s.d.) ratio of unsaturated to saturated membrane fatty acids within the plasma membrane was 2.57 ± 0.50, and was determined to be higher than a similar analysis of the lipids found in the acrosomal membrane (0.70 ± 0.10). The saltwater crocodile sperm plasma membrane also contained remarkably high levels of cholesterol (mean (± s.d.) 40.7 ± 4.5 nmol per 106 sperm cells) compared with the spermatozoa of other amniote species that have so far been documented. We suggest that this high cholesterol content could be conferring stability to the crocodile sperm membrane, allowing it to tolerate extreme osmotic fluxes and rapid changes in temperature. Our descriptive analysis now provides those interested in reptile and comparative sperm physiology an improved baseline database for interpreting biochemical changes associated with preservation pathology (e.g. cold shock and cryoinjury), epididymal sperm maturation and capacitation/acrosome reaction.
TL;DR: This chapter describes detailed practical procedures to assess the acrosomal status of human spermatozoa using light optical and epifluorescence microscopy, flow cytometry, and transmission electron microscopy to measure acrosome exocytosis in human sperm.
Abstract: Acrosome reaction is an exocytic process that enables a sperm to penetrate the zona pellucida and fertilize an egg. The process involves the fenestration and vesiculation of the sperm plasma membrane and outer acrosomal membrane, releasing the acrosomal content. Given the importance of the acrosome secretion in fertilization, many different methods have been developed to detect the acrosome reaction of sperm. In this chapter, we describe detailed practical procedures to assess the acrosomal status of human spermatozoa. To do this, we resorted to light optical and epifluorescence microscopy, flow cytometry, and transmission electron microscopy. We also itemize the protocol for real-time measurements of the acrosome reaction by confocal microscopy. Further, we discuss the level of complexity, costs, and the reasons why a researcher should choose each technique.This chapter is designed to provide the user with sufficient background to measure acrosomal exocytosis in human sperm.
TL;DR: In this paper, the authors investigated the position change of PRDX6 in human sperm under oxidative stress during cryopreservation Semen samples were obtained from 98 healthy donors and 27 asthenozoospermic donors.
TL;DR: In this article, the authors examined contributors to stallion sperm capacitation by investigating bicarbonate-induced membrane remodelling steps, and elucidating the contribution of cAMP signalling to these events.
Abstract: Classical in vitro fertilization (IVF) is still poorly successful in horses. This lack of success is thought to be due primarily to inadequate capacitation of stallion spermatozoa under in vitro conditions. In species in which IVF is successful, bicarbonate, calcium and albumin are considered the key components that enable a gradual reorganization of the sperm plasma membrane that allows the spermatozoa to undergo an acrosome reaction and fertilize the oocyte. The aim of this work was to comprehensively examine contributors to stallion sperm capacitation by investigating bicarbonate-induced membrane remodelling steps, and elucidating the contribution of cAMP signalling to these events. In the presence of capacitating media containing bicarbonate, a significant increase in plasma membrane fluidity was readily detected using merocyanine 540 staining in the majority of viable spermatozoa within 15 min of bicarbonate exposure. Specific inhibition of soluble adenylyl cyclase (sAC) in the presence of bicarbonate by LRE1 significantly reduced the number of viable sperm with high membrane fluidity. This suggests a vital role for sAC-mediated cAMP production in the regulation of membrane fluidity. Cryo-electron tomography of viable cells with high membrane fluidity revealed a range of membrane remodelling intermediates, including destabilized membranes and zones with close apposition of the plasma membrane and the outer acrosomal membrane. However, lipidomic analysis of equivalent viable spermatozoa with high membrane fluidity demonstrated that this phenomenon was neither accompanied by a gross change in the phospholipid composition of stallion sperm membranes nor detectable sterol efflux (p>0.05). After an early increase in membrane fluidity, a significant and cAMP-dependent increase in viable sperm with phosphatidylserine (PS), but not phosphatidylethanolamine (PE) exposure was noted. While the events observed partly resemble findings from the in vitro capacitation of sperm from other mammalian species, the lack of cholesterol removal appears to be an equine-specific phenomenon. This research will assist in the development of a defined medium for the capacitation of stallion sperm and will facilitate progress toward a functional IVF protocol for horse gametes.
TL;DR: In this paper, the authors determined the changes in the existence and location of the sperm plasma membrane and acrosome in the presence of sperm freezing and found that sperm freezing destroys the integrity of the plasma membrane.
Abstract: According to various reports, current methods of sperm freezing destroy the integrity of the sperm plasma membrane and acrosome. This study aimed to determine the changes in the existence and locat...
19 Feb 2021
TL;DR: In this article, the association of Doppler ultrasound with clinical andrological examination to identify the reproductive quality of stallions in paraiban swamp region was evaluated, and it was concluded that when isolated, does not determine the fertile capacity of stallion; doppler-associated ultrasound identifies subfertile animals and can be an auxiliary tool in stallions selection.
Abstract: This study aimed to evaluate the association of Doppler ultrasound with clinical andrological examination to identify the reproductive quality of stallions in paraiban swamp region. Eleven horses were used, aged between three and 27 years. The ejaculates were collected by the artificial vagina method and the seminal samples were submitted to field evaluation (subjective motility, cellular integrity) and in the laboratory (objective motility, cellular integrity). After seminal collection, the animals were submitted to testicular blood flow evaluation with Doppler ultrasound. Differences (P<0.05) were observed between the parameters of subjective motility, field-evaluated, and objective motility, in the laboratory. The integrity of the sperm plasma membrane was similar in field and laboratory tests. In the ultrasound parameters, it was observed that the Pulsatility Index has a positive correlation with lateral head displacement amplitude (ALH) of the spermatozoa. Finally, when evaluating age parameter, elderly animals presented reduced motility and lower blood supply in the testicular region, resulting in low fertility. It is concluded that the clinical andrological examination, when isolated, does not determine the fertile capacity of stallions; doppler-associated ultrasound identifies subfertile animals and can be an auxiliary tool in the stallions selection.
TL;DR: In this paper, the effect of recombinant methionine sulfoxide reductase A (rMsrA) on the quality of cryopreserved spermatozoa was assessed in three treatment groups.
Abstract: BACKGROUND The excessive reactive oxygen species produced during semen-freezing and -thawing damage the macromolecules resulting in impairment of cellular functions. Proteins are the primary targets of oxidative damage, wherein methionine residues are more prone to oxidation and get converted into methionine sulfoxide, thus affecting the protein function. The methionine sulfoxide reductase A (MsrA) catalyzes the conversion of methionine sulfoxide to methionine and restores the functionality of defective proteins. OBJECTIVES To establish the expression of MsrA in male reproductive organs, including semen and its effect on quality of cryopreserved semen upon exogenous supplementation, taking buffalo semen as a model. MATERIALS AND METHODS The expression of MsrA was established by immunohistochemistry, PCR, and Western blots. Further, the effect of recombinant MsrA (rMsrA) supplementation on the quality of cryopreserved spermatozoa was assessed in three treatment groups containing 1.0, 1.5, and 2.0 µg of rMsrA/50 million spermatozoa in egg yolk glycerol extender along with a control group; wherein the post-thaw progressive motility, viability, membrane integrity, and zona binding ability of cryopreserved spermatozoa were studied. RESULTS The MsrA was expressed in buffalo testis, epididymis, accessory sex glands, and spermatozoa except in seminal plasma. In group 2, the supplementation has resulted in a significant (p < 0.05) improvement as compared to the control group in mean progressive motility (47.50 ± 2.50 vs. 36.25 ± 2.63), viability (56.47 ± 1.85 vs. 48.05 ± 2.42), HOST (50.76 ± 1.73 vs. 44.29 ± 1.29), and zona binding ability of spermatozoa (149.50 ± 8.39 vs. 29.50 ± 2.85). DISCUSSION AND CONCLUSION In the absence of native MsrA of seminal plasma, the supplementations of rMsrA may repair the oxidatively damaged seminal plasma proteins and exposed sperm plasma membrane proteins resulting in better quality with a fivefold increase in fertilizability of frozen-thawed spermatozoa. The findings can be extended to other species to improve the semen quality with the variation in the amounts of rMsrA supplementation.