Science.gov

Sample records for posttesticular sperm maturation

  1. Posttesticular sperm maturation, infertility, and hypercholesterolemia

    PubMed Central

    Whitfield, Marjorie; Pollet-Villard, Xavier; Levy, Rachel; Drevet, Joël R; Saez, Fabrice

    2015-01-01

    Cholesterol is a key molecule in the mammalian physiology of especial particular importance for the reproductive system as it is the common precursor for steroid hormone synthesis. Cholesterol is also a recognized modulator of sperm functions, not only at the level of gametogenesis. Cholesterol homeostasis regulation is crucial for posttesticular sperm maturation, and imbalanced cholesterol levels may particularly affect these posttesticular events. Metabolic lipid disorders (dyslipidemia) affect male fertility but are most of the time studied from the angle of endocrine/testicular consequences. This review will focus on the deleterious effects of a particular dyslipidemia, i.e., hypercholesterolemia, on posttesticular maturation of mammalian spermatozoa. PMID:26067871

  2. Post-Testicular Sperm Maturation: Centriole Pairs, Found in Upper Epididymis, are Destroyed Prior to Sperm's Release at Ejaculation.

    PubMed

    Simerly, C; Castro, C; Hartnett, C; Lin, C C; Sukhwani, M; Orwig, K; Schatten, G

    2016-01-01

    The fertilizing sperm's lengthiest unchartered voyage is through the longest, least-investigated organ in a man's body - the Epididymis. Over six meters long in men, ~80 meters in stallions and over one-hundred times a mouse's body length, there are few functions known aside from sperm storage and nutrition. While spermatogenesis is completed in the testes, here we demonstrate sperm centriole reduction occurs within the epididymis. Investigations of GFP-CENTR mice and controls demonstrate both the presence of centriole pairs in the upper caput region of the epididymis and, the destruction, first, of the distal and, then, of the proximal centriole as the sperm transits to the cauda and vas deferens in preparation for its climactic release. These centrioles can neither recruit γ-tubulin nor nucleate microtubules when eggs are inseminated or microinjected, yet numerous maternally-nucleated cytasters are found. These sperm centrioles appear as vestigial basal bodies, destroyed in the mid-to-lower corpus. Post-testicular sperm maturation, in which sperm centrioles found in the caput are destroyed prior to ejaculation, is a newly discovered function for the epididymis. PMID:27534805

  3. Post-Testicular Sperm Maturation: Centriole Pairs, Found in Upper Epididymis, are Destroyed Prior to Sperm's Release at Ejaculation.

    PubMed

    Simerly, C; Castro, C; Hartnett, C; Lin, C C; Sukhwani, M; Orwig, K; Schatten, G

    2016-08-18

    The fertilizing sperm's lengthiest unchartered voyage is through the longest, least-investigated organ in a man's body - the Epididymis. Over six meters long in men, ~80 meters in stallions and over one-hundred times a mouse's body length, there are few functions known aside from sperm storage and nutrition. While spermatogenesis is completed in the testes, here we demonstrate sperm centriole reduction occurs within the epididymis. Investigations of GFP-CENTR mice and controls demonstrate both the presence of centriole pairs in the upper caput region of the epididymis and, the destruction, first, of the distal and, then, of the proximal centriole as the sperm transits to the cauda and vas deferens in preparation for its climactic release. These centrioles can neither recruit γ-tubulin nor nucleate microtubules when eggs are inseminated or microinjected, yet numerous maternally-nucleated cytasters are found. These sperm centrioles appear as vestigial basal bodies, destroyed in the mid-to-lower corpus. Post-testicular sperm maturation, in which sperm centrioles found in the caput are destroyed prior to ejaculation, is a newly discovered function for the epididymis.

  4. Epididymal protein Rnase10 is required for post-testicular sperm maturation and male fertility.

    PubMed

    Krutskikh, Anton; Poliandri, Ariel; Cabrera-Sharp, Victoria; Dacheux, Jean Louis; Poutanen, Matti; Huhtaniemi, Ilpo

    2012-10-01

    Eutherian spermatozoa are dependent on the environment of the proximal epididymis to complete their maturation; however, no specific epididymal factors that mediate this process have so far been identified. Here, we show that targeted disruption of the novel gene Rnase10 encoding a secreted proximal epididymal protein in the mouse results in a binding defect in spermatozoa and their inability to pass through the uterotubal junction in the female. The failure to gain the site of fertilization in the knockout spermatozoa is associated with a gradual loss of ADAM3 and ADAM6 proteins during epididymal transit. In the distal epididymis, these spermatozoa appear to lack calcium-dependent associations with the immobilizing glutinous extracellular material and are released as single, vigorously motile cells that display no tendency for head-to-head agglutination and lack affinity to the oviductal epithelium. In sperm-egg binding assay, they are unable to establish a tenacious association with the zona pellucida, yet they are capable of fertilization. Furthermore, these sperm show accelerated capacitation resulting in an overall in vitro fertilizing ability superior to that of wild-type sperm. We conclude that the physiological role of sperm adhesiveness is in the mechanism of restricted sperm entry into the oviduct rather than in sperm-egg interaction. PMID:22750516

  5. Post-Testicular Sperm Maturation: Centriole Pairs, Found in Upper Epididymis, are Destroyed Prior to Sperm’s Release at Ejaculation

    PubMed Central

    Simerly, C.; Castro, C.; Hartnett, C.; Lin, C. C.; Sukhwani, M.; Orwig, K.; Schatten, G.

    2016-01-01

    The fertilizing sperm’s lengthiest unchartered voyage is through the longest, least-investigated organ in a man’s body – the Epididymis. Over six meters long in men, ~80 meters in stallions and over one-hundred times a mouse’s body length, there are few functions known aside from sperm storage and nutrition. While spermatogenesis is completed in the testes, here we demonstrate sperm centriole reduction occurs within the epididymis. Investigations of GFP-CENTR mice and controls demonstrate both the presence of centriole pairs in the upper caput region of the epididymis and, the destruction, first, of the distal and, then, of the proximal centriole as the sperm transits to the cauda and vas deferens in preparation for its climactic release. These centrioles can neither recruit γ-tubulin nor nucleate microtubules when eggs are inseminated or microinjected, yet numerous maternally-nucleated cytasters are found. These sperm centrioles appear as vestigial basal bodies, destroyed in the mid-to-lower corpus. Post-testicular sperm maturation, in which sperm centrioles found in the caput are destroyed prior to ejaculation, is a newly discovered function for the epididymis. PMID:27534805

  6. Implication of the estrogen receptors GPER, ESR1, ESR2 in post-testicular maturations of equine spermatozoa.

    PubMed

    Gautier, Camille; Barrier-Battut, Isabelle; Guénon, Isabelle; Goux, Didier; Delalande, Christelle; Bouraïma-Lelong, Hélène

    2016-07-01

    Estrogen receptors ESR1, ESR2 and GPER are present on mature ejaculated horse spermatozoa, suggesting these cells as putative targets for estrogens. Indeed, spermatozoa are exposed to high level of estrogens during the transit in the male and female genital tracts but their roles are not investigated. So, we evaluated in vitro the role of 17β-estradiol during post-testicular maturations: regulation of motility, capacitation and acrosome reaction. Moreover according to the pseudo-seasonal breeder status of the stallion, we analyzed the putative seasonal variations in the presence of ESRs in spermatozoa. We showed that ESRs are more present on stallion sperm during the breeding season. We showed that capacitation and acrosome reaction are independent of estradiol action in horse. Estradiol can weakly modulate the motility and this effect is strictly associated with GPER and not with ESR1 and ESR2. The subcellular localization of GPER in the neck on stallion sperm is coherent with this effect. It seems that estrogens are not major regulators of sperm maturations associated to mare genital tract, so they could act during the epididymal maturations. PMID:27222348

  7. Sperm Proteome Maturation in the Mouse Epididymis

    PubMed Central

    Skerget, Sheri; Rosenow, Matthew A.; Petritis, Konstantinos; Karr, Timothy L.

    2015-01-01

    In mammals, transit through the epididymis, which involves the acquisition, loss and modification of proteins, is required to confer motility and fertilization competency to sperm. The overall dynamics of maturation is poorly understood, and a systems level understanding of the complex maturation process will provide valuable new information about changes occurring during epididymal transport. We report the proteomes of sperm collected from the caput, corpus and cauda segments of the mouse epididymis, identifying 1536, 1720 and 1234 proteins respectively. This study identified 765 proteins that are present in sperm obtained from all three segments. We identified 1766 proteins that are potentially added (732) or removed (1034) from sperm during epididymal transit. Phenotypic analyses of the caput, corpus and cauda sperm proteomes identified 60 proteins that have known sperm phenotypes when mutated, or absent from sperm. Our analysis indicates that as much as one-third of proteins with known sperm phenotypes are added to sperm during epididymal transit. GO analyses revealed that cauda sperm are enriched for specific functions including sperm-egg recognition and motility, consistent with the observation that sperm acquire motility and fertilization competency during transit through the epididymis. In addition, GO analyses revealed that the immunity protein profile of sperm changes during sperm maturation. Finally, we identified components of the 26S proteasome, the immunoproteasome, and a proteasome activator in mature sperm. PMID:26556802

  8. Monotremes provide a key to understanding the evolutionary significance of epididymal sperm maturation.

    PubMed

    Nixon, Brett; Ecroyd, Heath W; Dacheux, Jean-Louis; Jones, Russell C

    2011-01-01

    It has been widely accepted that mammalian spermatozoa are infertile when they leave the testes and require a period of maturation in both the epididymis and the female reproductive tract before acquiring the ability to fertilize an oocyte. However, the necessity for such a complex process of posttesticular sperm maturation appears to be unique to mammals because it is well established that these processes do not directly influence the fertilizing ability of the spermatozoa of birds, reptiles, and other lower vertebrates. Because of their key evolutionary position and form of reproduction, we contend that monotremes (platypus and echidna) provide a unique model for resolving why these processes are necessary. In the present review, we examine evidence that the epididymal maturation of monotreme spermatozoa is far less complex than in other mammals. However, a unique feature of the monotreme epididymis lies in its ability to promote the formation of elaborate sperm bundles that serve to greatly enhance the cells' motility. It is suggested that this intriguing cooperative strategy used by monotreme sperm represents an early form of epididymal maturation that appears to have been elaborated upon during the evolution of higher mammals, possibly as an adaptation for sperm competition.

  9. Monotremes provide a key to understanding the evolutionary significance of epididymal sperm maturation.

    PubMed

    Nixon, Brett; Ecroyd, Heath W; Dacheux, Jean-Louis; Jones, Russell C

    2011-01-01

    It has been widely accepted that mammalian spermatozoa are infertile when they leave the testes and require a period of maturation in both the epididymis and the female reproductive tract before acquiring the ability to fertilize an oocyte. However, the necessity for such a complex process of posttesticular sperm maturation appears to be unique to mammals because it is well established that these processes do not directly influence the fertilizing ability of the spermatozoa of birds, reptiles, and other lower vertebrates. Because of their key evolutionary position and form of reproduction, we contend that monotremes (platypus and echidna) provide a unique model for resolving why these processes are necessary. In the present review, we examine evidence that the epididymal maturation of monotreme spermatozoa is far less complex than in other mammals. However, a unique feature of the monotreme epididymis lies in its ability to promote the formation of elaborate sperm bundles that serve to greatly enhance the cells' motility. It is suggested that this intriguing cooperative strategy used by monotreme sperm represents an early form of epididymal maturation that appears to have been elaborated upon during the evolution of higher mammals, possibly as an adaptation for sperm competition. PMID:21441429

  10. A 33 kDa molecular marker of sperm acrosome differentiation and maturation in the tammar wallaby (Macropus eugenii).

    PubMed

    Wade, M A; Lin, M

    1999-09-01

    This study was undertaken to identify potential molecular markers of acrosomal biogenesis and post-testicular maturation in marsupials, using the tammar wallaby as a model species. A two-step sperm extraction procedure yielded two protein extracts of apparent acrosomal origin and a tail extract. The extracts were analysed by SDS-PAGE under reducing conditions. Several prominent polypeptide bands (45, 38 and 33 kDa) appeared common to both acrosomal extracts. Antiserum raised against the 33 kDa polypeptide from the inner acrosomal membrane matrix (IAMM) extract showed immunoreactivity with 45, 38 and 33 kDa polypeptides in both acrosomal extracts, indicating that the 33 kDa polypeptide was related to the proteins in the 45 and 38 kDa bands. Therefore, the antiserum was used as a molecular probe. Indirect immuno-fluorescence indicated that the acrosome was the major location of the 33 kDa polypeptide. This contention was confirmed by ultrastructural study: immunogold labelling indicated that the 33 kDa polypeptide associated with acrosomal matrix components throughout acrosomal development in the testes and throughout post-testicular maturation in the epididymis. The label clearly delineated the changing morphology of the maturing marsupial acrosome. This is the first study to use immunocytochemical techniques to chart testicular and post-testicular development of any sperm organelle in a marsupial. As a result of this study, a 33 kDa molecular marker of marsupial acrosome differentiation and maturation has been identified. It may be possible to chart similar events in other marsupial species and identify opportunities for manipulating fertility. PMID:10645248

  11. Sterols in spermatogenesis and sperm maturation.

    PubMed

    Keber, Rok; Rozman, Damjana; Horvat, Simon

    2013-01-01

    Mammalian spermatogenesis is a complex developmental program in which a diploid progenitor germ cell transforms into highly specialized spermatozoa. One intriguing aspect of sperm production is the dynamic change in membrane lipid composition that occurs throughout spermatogenesis. Cholesterol content, as well as its intermediates, differs vastly between the male reproductive system and nongonadal tissues. Accumulation of cholesterol precursors such as testis meiosis-activating sterol and desmosterol is observed in testes and spermatozoa from several mammalian species. Moreover, cholesterogenic genes, especially meiosis-activating sterol-producing enzyme cytochrome P450 lanosterol 14α-demethylase, display stage-specific expression patterns during spermatogenesis. Discrepancies in gene expression patterns suggest a complex temporal and cell-type specific regulation of sterol compounds during spermatogenesis, which also involves dynamic interactions between germ and Sertoli cells. The functional importance of sterol compounds in sperm production is further supported by the modulation of sterol composition in spermatozoal membranes during epididymal transit and in the female reproductive tract, which is a prerequisite for successful fertilization. However, the exact role of sterols in male reproduction is unknown. This review discusses sterol dynamics in sperm maturation and describes recent methodological advances that will help to illuminate the complexity of sperm formation and function.

  12. Dietary Cholesterol-Induced Post-Testicular Infertility

    PubMed Central

    Ouvrier, Aurélia; Alves, Georges; Damon-Soubeyrand, Christelle; Marceau, Geoffroy; Cadet, Rémi; Janny, Laurent; Brugnon, Florence; Kocer, Ayhan; Pommier, Aurélien; Lobaccaro, Jean-Marc A.; Drevet, Joël R.; Saez, Fabrice

    2011-01-01

    This work shows that an overload of dietary cholesterol causes complete infertility in dyslipidemic male mice (the Liver X Receptor-deficient mouse model). Infertility resulted from post-testicular defects affecting the fertilizing potential of spermatozoa. Spermatozoa of cholesterol-fed lxr−/− animals were found to be dramatically less viable and motile, and highly susceptible to undergo a premature acrosome reaction. We also provide evidence, that this lipid-induced infertility is associated with the accelerated appearance of a highly regionalized epididymal phenotype in segments 1 and 2 of the caput epididymidis that was otherwise only observed in aged LXR-deficient males. The epididymal epithelial phenotype is characterized by peritubular accumulation of cholesteryl ester lipid droplets in smooth muscle cells lining the epididymal duct, leading to their transdifferentiation into foam cells that eventually migrate through the duct wall, a situation that resembles the inflammatory atherosclerotic process. These findings establish the high level of susceptibility of epididymal sperm maturation to dietary cholesterol overload and could partly explain reproductive failures encountered by young dyslipidemic men as well as ageing males wishing to reproduce. PMID:22073227

  13. Impaired Sperm Maturation in Rnase9 Knockout Mice1

    PubMed Central

    Westmuckett, Andrew D.; Nguyen, Edward B.; Herlea-Pana, Oana M.; Alvau, Antonio; Salicioni, Ana M.; Moore, Kevin L.

    2014-01-01

    ABSTRACT Ribonuclease, RNase A family, 9 (RNASE9) is a ribonuclease A superfamily member that is expressed only in the epididymis. It is a small, secreted polypeptide, it lacks ribonuclease activity, and its function(s) is unknown. However, epididymis-specific expression suggests a role in sperm maturation. We generated Rnase9−/− mice to study RNASE9 function in vivo. We confirm that RNASE9 expression is restricted to the epididymis. Within the epididymis, RNASE9 is first detected in midcaput, persists through the distal caput and corpus, and wanes in the cauda. Rnase9−/− mice are born at the expected Mendelian ratio, have normal postnatal growth and development, and have no outwardly apparent phenotype. Spermatogenesis is normal, and Rnase9-null sperm are morphologically normal. Rnase9−/− males have normal fertility in unrestricted mating trials, and fertilization rates in in vitro fertilization assays are indistinguishable from wild-type mice. Visual observations coupled with analyses of sperm velocities shortly after swim out from the corpus shows that motility of Rnase9-null sperm is significantly impaired. However, no differences between wild-type and Rnase9-null sperm are detected by computer-assisted sperm analysis 10–90 min after sperm isolation from the corpus or cauda. Assessment of capacitation-dependent signaling pathways in Rnase9-null sperm showed that, while levels of tyrosine phosphorylation of sperm proteins were normal, there was decreased phosphorylation of protein kinase A substrates upon capacitation compared to wild-type mice. In conclusion, RNASE9 is dispensable for fertility, but the absence of RNASE9 during epididymal transit results in impaired sperm maturation. PMID:24719258

  14. Study of Sperm Reproductive Parameters in Mature Zanjani Viper

    PubMed Central

    Moshiri, Malihe; Todehdehghan, Fatemeh; Shiravi, Abdolhossein

    2014-01-01

    Objective Zanjani viper (Vipera albicornuta) is an endemic venomous snake in East Azerbai- jan Province, Iran which is medically important due to its application for antivenin production in the laboratory. We need to produce this snake in captivity. This study was conducted to charac- terize mature male Zanjani viper and to evaluate its sperm reproductive parameters. Materials and Methods This applied- descriptive study was conducted on twenty Zan- jani viper samples collected from Ag Dag Mountain in East Azarbaijan Province, Iran, between September and October 2010. After the snakes were anesthetized and sacrificed humanly, their morphometric specifications and sperm reproductive parameters, including concentration, motility, vitality, morphology, and survival time, were measured. Results Morphometric specifications and evaluation of sperms of the snake showed the following information: Zanjani male viper, body length of 73.65 ± 4.35 cm, tail length of 5.465 ± 0.48 cm, and mature snakes with testicular volumes of 0.61 ± 0.81 ml (right) and of 0.46 ± 0.17 ml (left). Our findings revealed average sperm concen- tration of 0.47 ± 0.1 ×106ml-1, motility of 49 -55 %, vitality of 46.11 ± 9.63 %, normal morphology of 61.71 ± 5.3%, and survival time of 6 ± 2 hours at the laboratory tem- perature. Statistical analyses were performed using Student’s t test for comparison of two values, and one-way ANOVA was applied where three values were compared. Conclusion Results suggest that mature Zanjani male viper with mature sperms in its vas deferens is present in late summer and early autumn seasons in Bostanabad County, Iran. PMID:24567940

  15. Experimental evidence that sperm maturation drives protandry in an ectotherm.

    PubMed

    Breedveld, Merel C; Fitze, Patrick S

    2016-09-01

    Protandry, i.e., the earlier arrival to breeding areas of males than females, has attracted a lot of scientific attention. However, evidence for the evolutionary hypotheses of protandry is surprisingly scarce. Here, we experimentally manipulate the time of emergence from hibernation of males, relative to females, in the common lizard, Zootoca vivipara. We test whether the timing of emergence affects sperm maturation and mating success, to disentangle among proposed selective advantages of protandry. Our results experimentally demonstrate that the timing of emergence affects the date of sperm presence. Moreover, the degree of protandry affected whether males had sperm upon their first encounter with females, but it did not affect the probability of copulating. Mating occurred independent of male fertility and mating during infertility was least common in early emerging males. Early emergence from hibernation by males, relative to females, thus increases the male's chance of fertilising eggs and later emergence from hibernation by females reduces the female's probability of mating with infertile males. These results point to direct reproductive benefits of protandry in males and females, where earlier emergence is predicted to increase the male's opportunities to inseminate mates, and later emergence reduces the female's probability of copulating with infertile males. This suggests that protandry evolved due to the time required for sperm maturation after emergence from hibernation. PMID:27259749

  16. Is sperm motility maturation affected by static magnetic fields?

    PubMed Central

    Tablado, L; Pérez-Sánchez, F; Soler, C

    1996-01-01

    Kinematic parameters were evaluated in mouse epididymal extracts to monitor maturation of sperm movement in animals exposed to static magnetic fields using the Sperm-Class Analyzer computerized image analysis system. For this purpose, animals were exposed to a field of 0.7 T generated by a permanent magnet over 10 or 35 days for either 1 or 24 hr/day. The values of the motion endpoints were similar in animals used as controls and in those exposed to the nonionizing radiation, whatever the period of exposure or daily dosage. Changes in motility were observed in all groups: the percentage of total motile and progressive motile spermatozoa increased during passage through the epididymis, with major changes between the caput and corpus epididymides, and the pattern of swimming changed clearly towards more rapid and straighter trajectories. The processes of initiation of sperm motility and maturation of displacement patterns were not then affected by magnetic treatment. Moreover, it appears that sperm production is unaffected because no changes were observed in testicular or epididymal weights after exposure to static magnetic fields. Images Figure 1. Figure 2. Figure 3. PMID:8959411

  17. Sperm maturation in dogs: sperm profile and enzymatic antioxidant status in ejaculated and epididymal spermatozoa.

    PubMed

    Angrimani, D S R; Lucio, C F; Veiga, G A L; Silva, L C G; Regazzi, F M; Nichi, M; Vannucchi, C I

    2014-09-01

    Spermatozoa become more susceptible to the attack of reactive oxygen species during maturation. To avoid oxidative damage, the epididymis must provide the necessary antioxidant protection. The aim of this study was to compare the canine sperm profile and the enzymatic antioxidant status of the ejaculated fractions and samples collected from the different segments of the epididymis (caput, corpus and cauda). Five adult dogs were used, and after 1-3 weeks, subsequently to bilateral orchiectomy and epididymal storage, sperm samples were collected from the different segments of the epididymis. Samples were evaluated for conventional microscopy and computer-assisted motility analysis: sperm plasma membrane permeability and the activity of the antioxidant enzymes catalase, glutathione peroxidase (GPx) and superoxide dismutase (SOD). Samples collected from the caput and corpus showed lower values for most of the motility variables evaluated, indicating different levels of immaturity. Catalase activity was observed only in ejaculated samples. Conversely, GPx activity was higher in the cauda epididymidis. Correlations were found between SOD and GPx and SOD and sperm motility in the epididymal cauda and corpus, highlighting the importance of the enzymes for the protection of spermatozoa during the transit along the epididymis.

  18. Characterization of maturation-dependent extrinsic proteins of the rat sperm surface

    SciTech Connect

    Rifkin, J.M.; Olson, G.E.

    1985-05-01

    Mammalian spermatozoa must mature in the epididymis before they can fertilize an egg. It is known that modification of the protein composition of the sperm surface is an important part of the maturation process. In this paper, the authors present data on two related glycoproteins that can be extracted from mature but not immature spermatozoa. Cell surface radioiodination has shown that these proteins are on the sperm surface, and immunofluorescence microscopy, by use of monospecific antibodies to the proteins, has indicated that their localization is restricted to the periacrosomal region of the sperm head. The authors have also shown that in vitro, these proteins will bind to the identical region of immature sperm. Immunohistochemical localization of the proteins in the epididymis shows that they are produced and secreted by the cauda region. The significance of the addition of these proteins to the sperm surface in both maturation and fertilization is discussed.

  19. Characterization of maturation-dependent extrinsic proteins of the rat sperm surface

    PubMed Central

    1985-01-01

    Mammalian spermatozoa must mature in the epididymis before they can fertilize an egg. It is known that modification of the protein composition of the sperm surface is an important part of the maturation process. In this paper, we present data on two related glycoproteins that can be extracted from mature but not immature spermatozoa. Cell surface radioiodination has shown that these proteins are on the sperm surface, and immunofluorescence microscopy, by use of monospecific antibodies to the proteins, has indicated that their localization is restricted to the periacrosomal region of the sperm head. We have also shown that in vitro, these proteins will bind to the identical region of immature sperm. Immunohistochemical localization of the proteins in the epididymis shows that they are produced and secreted by the cauda region. The significance of the addition of these proteins to the sperm surface in both maturation and fertilization is discussed. PMID:3886668

  20. Sialylation Facilitates the Maturation of Mammalian Sperm and Affects Its Survival in Female Uterus.

    PubMed

    Ma, Xue; Pan, Qian; Feng, Ying; Choudhury, Biswa P; Ma, Qianhong; Gagneux, Pascal; Ma, Fang

    2016-06-01

    Establishment of adequate levels of sialylation is crucial for sperm survival and function after insemination; however, the mechanism for the addition of the sperm sialome has not been identified. Here, we report evidence for several different mechanisms that contribute to the establishment of the mature sperm sialome. Directly quantifying the source of the nucleotide sugar CMP-beta-N-acetylneuraminic acid in epididymal fluid indicates that transsialylation occurs in the upper epididymis. Western blots for the low-molecular-mass sialoglycoprotein (around 20-50 kDa) in C57BL/6 mice epididymal fluid reflect that additional sialome could be obtained by glycosylphosphatidylinositol-anchored sialoglycopeptide incorporation during epididymal transit in the caput of the epididymis. Additionally, we found that in Cmah (CMP-N-acetylneuraminic acid hydroxylase)-/- transgenic mice, epididymal sperm obtained sialylated-CD52 from seminal vesicle fluid (SVF). Finally, we used Gfp (green fluorescent protein)+/+ mouse sperm to test the role of sialylation on sperm for protection from female leukocyte attack. There is very low phagocytosis of the epididymal sperm when compared to that of sperm coincubated with SVF. Treating sperm with Arthrobacter ureafaciens sialidase (AUS) increased phagocytosis even further. Our results highlight the different mechanisms of increasing sialylation, which lead to the formation of the mature sperm sialome, as well as reveal the sialome's function in sperm survival within the female genital tract.

  1. Sperm bundles in the seminal vesicles of sexually mature Lasius ant males.

    PubMed

    Burnett, William E; Heinze, Jürgen

    2014-01-01

    In many insects, sperm cells are produced in bundles with their heads being held together by a glycoprotein matrix secreted by a cyst cell. Mature sperm cells in the seminal vesicles are usually free, but in sawflies and several other insects, such structures (spermatodesmata) remain intact and sperm cells may be ejaculated as bundles. Here we report the occurrence of spermatodesmata in mature males of the ant Lasius pallitarsis. Microscopic investigations of the abdominal contents of males immediately prior to their nuptial flights showed that the anterior ends of numerous sperm cells were embedded in an oval-shaped 20 by 30 micrometer extracellular fibrous cap. Individual sperm ranged in length from 55 to 75 micrometers with an average overall length of 65 micrometers. The bulb-shaped heads of the sperm were relatively small, only about 1.5 micrometers in length and about 1.1 micrometers in diameter. The diameter of the sperm tails was approximately 1 micrometer. Observations of live preparations of the spermatodesmata showed increasingly active undulating wave-like movement of the sperm tails as the slide preparations aged. This appears to be the first case of sperm bundles being present in the seminal vesicles of mature ant males--males that are immediately poised to complete their nuptial mating flight.

  2. Sperm Bundles in the Seminal Vesicles of Sexually Mature Lasius Ant Males

    PubMed Central

    Burnett, William E.; Heinze, Jürgen

    2014-01-01

    In many insects, sperm cells are produced in bundles with their heads being held together by a glycoprotein matrix secreted by a cyst cell. Mature sperm cells in the seminal vesicles are usually free, but in sawflies and several other insects, such structures (spermatodesmata) remain intact and sperm cells may be ejaculated as bundles. Here we report the occurrence of spermatodesmata in mature males of the ant Lasius pallitarsis. Microscopic investigations of the abdominal contents of males immediately prior to their nuptial flights showed that the anterior ends of numerous sperm cells were embedded in an oval-shaped 20 by 30 micrometer extracellular fibrous cap. Individual sperm ranged in length from 55 to 75 micrometers with an average overall length of 65 micrometers. The bulb-shaped heads of the sperm were relatively small, only about 1.5 micrometers in length and about 1.1 micrometers in diameter. The diameter of the sperm tails was approximately 1 micrometer. Observations of live preparations of the spermatodesmata showed increasingly active undulating wave-like movement of the sperm tails as the slide preparations aged. This appears to be the first case of sperm bundles being present in the seminal vesicles of mature ant males – males that are immediately poised to complete their nuptial mating flight. PMID:24671307

  3. Cytotoxic sperm antibodies and in vitro fertilization of mature oocytes: a preliminary report.

    PubMed

    Mathur, S; Mathur, R S; Holtz, G L; Tsai, C C; Rust, P F; Williamson, H O

    1987-06-01

    The fertilization rates of mature oocytes during in vitro fertilization and embryo transfer (IVF-ET) using fetal cord serum-supplemented insemination media were greater than or equal to 57% for five infertile couples without sperm antibodies (group 1). But they were less than or equal to 50% for four of nine infertile couples (group 2) with cytotoxic sperm antibodies in both partners (n = 6) or the husband alone (n = 3). Two women in group 1 were successful in achieving normal, full-term pregnancies with the delivery of normal infants (chi2 = 4.2, P less than 0.05, by chi-square analysis). One of them consistently tested negative for sperm antibodies, while her husband was previously treated with antibiotics for infection and transient sperm antibodies in the seminal plasma. Subsequently, antibody titers in the husband were in the normal range when the successful IVF-ET was performed. One woman in group 2, with antibodies to her autoimmune husband's sperm but not control sperm and with a long-standing poor postcoital test sperm motility, conceived through artificial insemination with donor sperm (AID) after failing to conceive with her husband through IVF-ET. These data suggest that the presence of cytotoxic sperm antibodies in the serum and/or secretions of both partners reduces the rates of fertilization of mature oocytes in spite of using fetal cord serum in the IVF media. Pregnancy achievement is impaired in this group.

  4. Reactive oxygen species production and antioxidant enzyme activity during epididymal sperm maturation in Corynorhinus mexicanus bats.

    PubMed

    Arenas-Ríos, Edith; Rosado García, Adolfo; Cortés-Barberena, Edith; Königsberg, Mina; Arteaga-Silva, Marcela; Rodríguez-Tobón, Ahiezer; Fuentes-Mascorro, Gisela; León-Galván, Miguel Angel

    2016-03-01

    Prolonged sperm storage in the epididymis of Corynorhinus mexicanus bats after testicular regression has been associated with epididymal sperm maturation in the caudal region, although the precise factors linked with this phenomenon are unknown. The aim of this work is to determine the role of reactive oxygen species (ROS) and changes in antioxidant enzymatic activity occurring in the spermatozoa and epididymal fluid over time, in sperm maturation and storage in the caput, corpus and cauda of the bat epididymis. Our data showed that an increment in ROS production coincided with an increase in superoxide dismutase (SOD) activity in epididymal fluid and with a decrease in glutathione peroxidase (GPX) activity in the spermatozoa in at different time points and epididymal regions. The increase in ROS production was not associated with oxidative damage measured by lipid peroxidation. The results of the current study suggest the existence of a shift in the redox balance, which might be associated with sperm maturation and storage.

  5. Spermatogenesis, the mature sperm, and sperm egg association in Nematospiroides dubius

    NASA Technical Reports Server (NTRS)

    Clark, W. H., Jr.

    1974-01-01

    Nematode spermatogenesis was investigated using the strongyloid Nematospiroides dubius. The primary spermatocytes, development of spermatids, and changes in the sperm in the female tract are described.

  6. Glucose Regulated Protein 78 Phosphorylation in Sperm Undergoes Dynamic Changes during Maturation

    PubMed Central

    Lobo, Vivian; Rao, Parimala; Gajbhiye, Rahul; Kulkarni, Vijay; Parte, Priyanka

    2015-01-01

    GRP78, a resident endoplasmic reticulum (ER) chaperone involved in protein transport, folding and assembly, has been reported in sperm. It is shown to be localized in the neck region of human sperm. We have previously reported GRP78 to be less phosphorylated in asthenozoosperm.The present study aimed to determine whether sperm GRP78 undergoes phosphorylation changes during epididymal maturation and whether there are any differences in GRP78 phosphoforms in asthenozoosperm vis-à-vis normozoosperm. Testicular- and cauda epididymal- sperm from adult male Holtzman rats, and semen ejaculates collected from normal and asthenozoospermic individuals were investigated. DIGE carried out to determine phosphorylation of GRP78 in asthenozoosperm and normal sperm reveals a shift in the location of GRP78 of asthenozoosperm towards the alkaline pH, indicative of reduced GRP78 phosphorylation. Immunoprecipitation studies using antibodies specific to GRP78, serine-, threonine-, and tyrosine phosphorylation and Pan phospho antibody demonstrates GRP78 to be phosphorylated at all three residues in rat spermatozoa. Phosphatase assays using Calf intestinal alkaline phosphatase and Lambda protein phosphatase followed by nanofluidic proteomic immunoassay (NIA) show that in rat, GP4.96, GP4.94 and GP4.85 are the three phosphoforms in mature (caudal) sperm as against two phosphoforms GP4.96and GP4.94in immature (testicular) sperm. In mature human sperm GP5.04, GP4.96, and GP4.94were the 3 phosphoforms observed. GP4.94[P = 0.014]andGP5.04 [P = 0.02] are significantly reduced in asthenozoosperm. Ours is the first report indicating GRP78 in sperm to be phosphorylated at serine, threonine and tyrosine residues contrary to published literature reporting GRP78 not to be tyrosine phosphorylated. We report the presence of GRP78 phosphoforms in rat- and human- sperm and our data suggest that GRP78 phosphorylation in sperm undergoes spatial reorganization during epididymal maturation. Significant

  7. Effects of exposure to zearalenone on porcine oocytes and sperm during maturation and fertilization in vitro.

    PubMed

    Sambuu, Rentsenkhand; Takagi, Mitsuhiro; Namula, Zhao; Otoi, Takeshige; Shiga, Satoshi; Rodrigues Dos Santos, Regiane; Fink-Gremmels, Johanna

    2011-09-01

    The influence of acute exposure to zearalenone (ZEN) on porcine oocyte maturation, fertilization or sperm penetration ability during both in vitro maturation and fertilization was evaluated. First, oocytes were cultured in ZEN-containing (0-1000 µg/l) maturation medium and then fertilized. The oocytes maturing in vitro without ZEN were then fertilized in ZEN-containing fertilization medium. The maturation rates of oocytes and penetration ability of sperm decreased significantly in the presence of 1000 µg/l of ZEN. However, neither increases in the rates of degeneration and DNA fragmentation of oocytes nor reductions in normal and polyspermic fertilization were observed. ZEN did not affect the sperm penetration rates; however, 1000 µg/l ZEN had positive effects on normal and polyspermic fertilization rates. Therefore, it can be suggested that an acute exposure of porcine oocytes during maturation and of oocytes and sperm during fertilization to ZEN up to 1000 µg/l may not affect the fertility of the oocytes.

  8. Contribution of the secretory material of caecilian (amphibia: Gymnophiona) male Mullerian gland to motility of sperm: a study in Uraeotyphlus narayani.

    PubMed

    George, Jancy M; Smita, Mathew; Kadalmani, Balamuthu; Girija, Ramankutty; Oommen, Oommen V; Akbarsha, Mohammad A

    2005-02-01

    Caecilians are a unique group of limbless burrowing amphibians with discontinuous distribution. Several caecilian species are viviparous, and all practice internal fertilization. In amniotic vertebrates the sperm undergo post-testicular physiological maturation when they are initiated into motility under the influence of an epididymal secretion. Further, during ejaculation mammalian sperm are suspended in a fluid secreted by the male accessory sex glands, viz., prostate gland and seminal vesicles. Caecilians lack comparable glands, but still practice internal fertilization. Uniquely, male caecilians retain the Mullerian ducts in the adults as a pair of functional glands. It has long been hypothesized, based on indirect evidence, that the Mullerian gland would be a male accessory sex gland, secreting a fluid in which sperm are suspended during ejaculation and which would also provide nutritional support to the ejaculated sperm. In the present study, the secretory material of the Mullerian gland of Uraeotyphlus narayani was mixed with sperm obtained from the testis, and the changes in motility were recorded. Uraeotyphlus narayani sperm possess a perforatorium of the acrosome proceeding deep into the endonuclear canal of the nucleus. The midpiece is characterized by closely applied centrioles, the anterior ends of the axoneme and axial fiber, and a mitochondrial sheath. The long tail has an undulating membrane on one side, supported by the axoneme and an axial fiber. The live sperm possess a mitochondrial vesicle, also known as the cytoplasmic droplet, anywhere along the head and the midpiece, as in anuran sperm, which is shed from sperm that have ceased motility. Uraeotyphlus narayani sperm are motile the moment they are released directly from the testis, indicating that the sperm do not require post-testicular physiological maturation. On being mixed with the secretory material of the Mullerian gland, the spermatozoa are enhanced in speed as well as duration of

  9. Contribution of the secretory material of caecilian (amphibia: Gymnophiona) male Mullerian gland to motility of sperm: a study in Uraeotyphlus narayani.

    PubMed

    George, Jancy M; Smita, Mathew; Kadalmani, Balamuthu; Girija, Ramankutty; Oommen, Oommen V; Akbarsha, Mohammad A

    2005-02-01

    Caecilians are a unique group of limbless burrowing amphibians with discontinuous distribution. Several caecilian species are viviparous, and all practice internal fertilization. In amniotic vertebrates the sperm undergo post-testicular physiological maturation when they are initiated into motility under the influence of an epididymal secretion. Further, during ejaculation mammalian sperm are suspended in a fluid secreted by the male accessory sex glands, viz., prostate gland and seminal vesicles. Caecilians lack comparable glands, but still practice internal fertilization. Uniquely, male caecilians retain the Mullerian ducts in the adults as a pair of functional glands. It has long been hypothesized, based on indirect evidence, that the Mullerian gland would be a male accessory sex gland, secreting a fluid in which sperm are suspended during ejaculation and which would also provide nutritional support to the ejaculated sperm. In the present study, the secretory material of the Mullerian gland of Uraeotyphlus narayani was mixed with sperm obtained from the testis, and the changes in motility were recorded. Uraeotyphlus narayani sperm possess a perforatorium of the acrosome proceeding deep into the endonuclear canal of the nucleus. The midpiece is characterized by closely applied centrioles, the anterior ends of the axoneme and axial fiber, and a mitochondrial sheath. The long tail has an undulating membrane on one side, supported by the axoneme and an axial fiber. The live sperm possess a mitochondrial vesicle, also known as the cytoplasmic droplet, anywhere along the head and the midpiece, as in anuran sperm, which is shed from sperm that have ceased motility. Uraeotyphlus narayani sperm are motile the moment they are released directly from the testis, indicating that the sperm do not require post-testicular physiological maturation. On being mixed with the secretory material of the Mullerian gland, the spermatozoa are enhanced in speed as well as duration of

  10. Sperm nuclear expansion and meiotic maturation in normal and gynogenetic eggs of the scallop, Chlamys farreri

    NASA Astrophysics Data System (ADS)

    Pan, Ying; Li, Qi; Yu, Ruihai; Wang, Rucai

    2008-02-01

    Sperm nuclear expansion, meiosis and the association of the male and female pronuclei leading to the four-cell stage in normal Chlamys farreri eggs were observed under a fluorescence microscope. The effects of ultraviolet (UV) irradiation on the fertilizing sperm were also examined. Both normal and UV-irradiated sperm nuclei enlarged at three distinct phases (phase A, metaphase I; phase B, polar body formation; and phase C, female pronuclear development and expansion) that were temporally correlated with meiotic process of the maternal chromosomes. Sperm nuclei underwent a rapid, initial enlargement during phase A, but condensed slightly during phase B, then re-enlarged during phase C. The effects of UV irradiation were not apparent during transformation of the sperm nucleus into a male pronucleus, and there was not any apparent effect on meiotic maturation and development of the female pronucleus. However, the rate of expansion of the UV-irradiated sperm nuclei and the size of male pronuclei were reduced apparently. Unlike the female pronucleus, the male pronucleus derived from sperm genome inactivated by UV irradiation did not form chromosomes, but became a dense chromatin body (DCB). At mitotic anaphase, DCB did not participate in the karyokinesis of the first cleavage as evidenced by chromosomal nondisjunction, demonstrating the effectiveness of using UV irradiation to induce gynogenetic scallop embryos.

  11. Comparative Proteomic Identification of Mature and Immature Sperm in the Catfish Cranoglanis bouderius

    PubMed Central

    Xie, Shaolin; Wang, Chao; Lv, Zijun; Zou, Jixing

    2016-01-01

    To understand the molecular responses of mature and immature sperm in the catfish Cranoglanis bouderius, we used the iTRAQ proteomics approach to perform proteomic profiling of spermatogenesis in C. bouderius. As a result, 1,941 proteins were identified, including 361 differentially expressed proteins, 157 upregulated proteins and 204 downregulated proteins in mature sperm relative to immature sperm. All of the identified proteins were categorized into seven types of subcellular localizations and three molecular functions and were found to be involved in nine biological processes. All of the differential proteins were involved in 235 different pathways. Moreover, we found that the tricarboxylic acid (TCA) pathway played an important role in the energy metabolism of sperm and that the EABB pathway was involved in the mechanism of spermatogenesis. Our study is the first to use the iTRAQ-based proteomic approach to analyze the catfish sperm proteome, and the results we obtained using this approach are valuable for understanding the molecular mechanisms of fish spermatogenesis. PMID:26964044

  12. Intraflagellar transport is essential for mammalian spermiogenesis but is absent in mature sperm

    PubMed Central

    San Agustin, Jovenal T.; Pazour, Gregory J.; Witman, George B.

    2015-01-01

    Drosophila sperm are unusual in that they do not require the intraflagellar transport (IFT) system for assembly of their flagella. In the mouse, the IFT proteins are very abundant in testis, but we here show that mature sperm are completely devoid of them, making the importance of IFT to mammalian sperm development unclear. To address this question, we characterized spermiogenesis and fertility in the Ift88Tg737Rpw mouse. This mouse has a hypomorphic mutation in the gene encoding the IFT88 subunit of the IFT particle. This mutation is highly disruptive to ciliary assembly in other organs. Ift88−/− mice are completely sterile. They produce ∼350-fold fewer sperm than wild-type mice, and the remaining sperm completely lack or have very short flagella. The short flagella rarely have axonemes but assemble ectopic microtubules and outer dense fibers and accumulate improperly assembled fibrous sheath proteins. Thus IFT is essential for the formation but not the maintenance of mammalian sperm flagella. PMID:26424803

  13. Effect of abamectin exposure on semen parameters indicative of reduced sperm maturity: a study on farmworkers in Antalya (Turkey).

    PubMed

    Celik-Ozenci, C; Tasatargil, A; Tekcan, M; Sati, L; Gungor, E; Isbir, M; Usta, M F; Akar, M E; Erler, F

    2012-12-01

    Environmental exposure to pesticides may cause serious health risks including fertility and reproductive function. The aim of this study was to highlight whether there is a relationship between exposure to abamectin and male fertility parameters of farmworkers. Twenty male farmworkers who were using abamectin and 20 men not exposed to pesticides were recruited as experimental and control groups, respectively. Semen analysis, molecular markers of sperm maturity and serum reproductive hormone levels were evaluated. In experimental group, high plasma abamectin levels were detected. These men have decreased sperm motility. Moreover, diminished molecular markers of sperm maturity, such as decreased hyaluronic acid (HA) binding of sperm, increased numbers of aniline blue positive sperm and increased percentage of creatine kinase (CK) positive sperm, were observed in abamectin-exposed men. Their serum testosterone, LH and FSH levels did not change significantly. We conclude that exposure to abamectin may impair male fertility by effecting semen quality.

  14. Methyl-parathion decreases sperm function and fertilization capacity after targeting spermatocytes and maturing spermatozoa

    SciTech Connect

    Pina-Guzman, Belem; Sanchez-Gutierrez, M.; Marchetti, Francesco; Hernandez-Ochoa, I.; Solis-Heredia, M.J .; Quintanilla-Vega, B.

    2009-05-03

    Paternal germline exposure to organophosphorous pesticides (OP) has been associated with reproductive failures and adverse effects in the offspring. Methyl parathion (Me-Pa), a worldwide-used OP, has reproductive adverse effects and is genotoxic to sperm. Oxidative damage has been involved in the genotoxic and reproductive effects of OP. The purpose of this study was to determine the effects of Me-Pa on spermatozoa function and ability to fertilize. Male mice were exposed to Me-Pa (20 mg/kg bw, i.p.) and spermatozoa from epididymis-vas deferens were collected at 7 or 28 days post-treatment (dpt) to assess the effects on maturing spermatozoa and spermatocytes, respectively. DNA damage was evaluated by nick translation (NT-positive cells) and SCSA (percentDFI); lipoperoxidation (LPO) by malondialdehyde production; sperm function by spontaneous- and induced-acrosome reactions (AR); mitochondrial membrane potential (MMP) by using the JC-1 flurochrome; and, fertilization ability by an in vitro assay and in vivo mating. Results showed alterations in DNA integrity (percentDFI and NT-positive cells) at 7 and 28 dpt, in addition to decreased sperm quality and a decrease in induced-AR; reduced MMP and LPO was observed only at 7 dpt. We found negative correlations between LPO and all sperm alterations. Altered sperm functional parameters were associated with reduced fertilization rates at both times, evaluated either in vitro or in vivo. These results show that Me-Pa exposure of maturing spermatozoa and spermatocytes affects many sperm functional parameters that result in a decreased fertilizing capacity. Oxidative stress seems to be a likely mechanism ofthe detrimental effects of Me-Pa in male germ cells.

  15. Methyl-parathion decreases sperm function and fertilization capacity after targeting spermatocytes and maturing spermatozoa.

    PubMed

    Piña-Guzmán, B; Sánchez-Gutiérrez, M; Marchetti, F; Hernández-Ochoa, I; Solís-Heredia, M J; Quintanilla-Vega, B

    2009-07-15

    Paternal germline exposure to organophosphorous pesticides (OP) has been associated with reproductive failures and adverse effects in the offspring. Methyl-parathion (Me-Pa), a worldwide-used OP, has reproductive adverse effects and is genotoxic to sperm, possibly via oxidative damage. This study investigated the stages of spermatogenesis susceptible to be targeted by Me-Pa exposure that impact on spermatozoa function and their ability to fertilize. Male mice were exposed to Me-Pa (20 mg/kg bw, i.p.) and spermatozoa from epididymis-vas deferens were collected at 7 or 28 days post-treatment (dpt) to assess the effects on maturing spermatozoa and spermatocytes, respectively. Spermatozoa were examined for DNA damage by nick translation (NT-positive cells) and SCSA (%DFI), lipoperoxidation (LPO) by malondialdehyde production, sperm function by spontaneous- and induced-acrosome reactions (AR), mitochondrial membrane potential (MMP) by using the JC-1 fluorochrome, and fertilization ability by an in vitro assay and in vivo mating. Alterations on DNA integrity (%DFI and NT-positive cells) in spermatozoa collected at 7 and 28 dpt, and decreases in sperm quality and induced-AR were observed; reduced MMP and LPO were observed at 7 dpt only. Negative correlations between LPO and sperm alterations were found. Altered sperm functional parameters evaluated either in vitro or in vivo were associated with reduced fertilization rates at both times. These results show that Me-Pa exposure of maturing spermatozoa and spermatocytes affects many sperm functional parameters that result in a decreased fertilizing capacity. Oxidative stress seems to be a likely mechanism of the detrimental effects of Me-Pa exposure in male germ cells.

  16. Group III secreted phospholipase A2 regulates epididymal sperm maturation and fertility in mice

    PubMed Central

    Sato, Hiroyasu; Taketomi, Yoshitaka; Isogai, Yuki; Miki, Yoshimi; Yamamoto, Kei; Masuda, Seiko; Hosono, Tomohiko; Arata, Satoru; Ishikawa, Yukio; Ishii, Toshiharu; Kobayashi, Tetsuyuki; Nakanishi, Hiroki; Ikeda, Kazutaka; Taguchi, Ryo; Hara, Shuntaro; Kudo, Ichiro; Murakami, Makoto

    2010-01-01

    Although lipid metabolism is thought to be important for the proper maturation and function of spermatozoa, the molecular mechanisms that underlie this dynamic process in the gonads remains incompletely understood. Here, we show that group III phospholipase A2 (sPLA2-III), a member of the secreted phospholipase A2 (sPLA2) family, is expressed in the mouse proximal epididymal epithelium and that targeted disruption of the gene encoding this protein (Pla2g3) leads to defects in sperm maturation and fertility. Although testicular spermatogenesis in Pla2g3–/– mice was grossly normal, spermatozoa isolated from the cauda epididymidis displayed hypomotility, and their ability to fertilize intact eggs was markedly impaired. Transmission EM further revealed that epididymal spermatozoa in Pla2g3–/– mice had both flagella with abnormal axonemes and aberrant acrosomal structures. During epididymal transit, phosphatidylcholine in the membrane of Pla2g3+/+ sperm underwent a dramatic shift in its acyl groups from oleic, linoleic, and arachidonic acids to docosapentaenoic and docosahexaenoic acids, whereas this membrane lipid remodeling event was compromised in sperm from Pla2g3–/– mice. Moreover, the gonads of Pla2g3–/– mice contained less 12/15-lipoxygenase metabolites than did those of Pla2g3+/+ mice. Together, our results reveal a role for the atypical sPLA2 family member sPLA2-III in epididymal lipid homeostasis and indicate that its perturbation may lead to sperm dysfunction. PMID:20424323

  17. Testicular descent, sperm maturation and capacitation. Lessons from our most distant relatives, the monotremes.

    PubMed

    Ecroyd, Heath; Nixon, Brett; Dacheux, Jean-Louis; Jones, Russell C

    2009-01-01

    The present review examines whether monotremes may help to resolve three questions relating to sperm production in mammals: why the testes descend into a scrotum in most mammals, why spermatozoa are infertile when they leave the testes and require a period of maturation in the specific milieu provided by the epididymides, and why ejaculated spermatozoa cannot immediately fertilise an ovum until they undergo capacitation within the female reproductive tract. Comparisons of monotremes with other mammals indicate that there is a need for considerable work on monotremes. It is hypothesised that testicular descent should be related to epididymal differentiation. Spermatozoa and ova from both groups share many of the proteins that are thought to be involved in gamete interaction, and although epididymal sperm maturation is significant it is probably less complex in monotremes than in other mammals. However, the monotreme epididymis is unique in forming spermatozoa into bundles of 100 with greatly enhanced motility compared with individual spermatozoa. Bundle formation involves a highly organised interaction with epididymal proteins, and the bundles persist during incubation in vitro, except in specialised medium, in which spermatozoa separate after 2-3 h incubation. It is suggested that this represents an early form of capacitation.

  18. Effects of dietary energy on sexual maturation and sperm production in Holstein bulls.

    PubMed

    Harstine, B R; Maquivar, M; Helser, L A; Utt, M D; Premanandan, C; DeJarnette, J M; Day, M L

    2015-06-01

    In prepubertal bulls and heifers of dairy and beef breeds, puberty can be induced to occur earlier than typical with targeted high-energy diets due to precocious activation of the endocrine mechanisms that regulate puberty. Precocious activation of puberty in bulls intended for use in the AI industry has the potential to hasten and perhaps increase sperm production. It was hypothesized that feeding bulls a high-energy diet beginning at 8 wk of age would advance the prepubertal rise in LH and lead to advanced testicular maturation and age at puberty. From 58 to 230 ± 0.3 d of age, Holstein bulls received either a high-energy diet (HE;n = 9; targeted ADG 1.5 kg/d) or a control diet (CONT;n = 10; targeted ADG 0.75 kg/d). Thereafter, all bulls were fed a similar diet. The HE treatment increased LH secretion at 125 d of age, testosterone concentrations from 181 to 210 d, and scrotal circumference (SC) from 146 to 360 d of age relative to the CONT treatment. Beginning at 241 ± 5 d of age, semen collection (artificial vagina) was attempted every 14 d in bulls from the HE (n = 8) and CONT (n = 7) treatment until each bull attained puberty (ejaculate containing 50 × 10 spermatozoa with 10% motility). To assess semen production as mature bulls, semen was collected thrice weekly beginning at 541 ± 5 d of age until slaughter at 569 ± 5 d of age. After slaughter, epididymal and testicular measurements were collected and testicular tissue was fixed to determine seminiferous tubule diameter. Age at puberty did not differ between treatments (310 ± 35 d). Although testis and epididymal weight and testis volume were greater (P < 0.05) in the HE than the CONT treatment, sperm production of mature bulls did not differ between treatments. Diameter of seminiferous tubules also did not differ between treatments. We conclude that the HE advanced aspects of sexual maturation and increased testes size, but this was not reflected in hastened puberty or sperm production in the present

  19. Effects of dietary energy on sexual maturation and sperm production in Holstein bulls.

    PubMed

    Harstine, B R; Maquivar, M; Helser, L A; Utt, M D; Premanandan, C; DeJarnette, J M; Day, M L

    2015-06-01

    In prepubertal bulls and heifers of dairy and beef breeds, puberty can be induced to occur earlier than typical with targeted high-energy diets due to precocious activation of the endocrine mechanisms that regulate puberty. Precocious activation of puberty in bulls intended for use in the AI industry has the potential to hasten and perhaps increase sperm production. It was hypothesized that feeding bulls a high-energy diet beginning at 8 wk of age would advance the prepubertal rise in LH and lead to advanced testicular maturation and age at puberty. From 58 to 230 ± 0.3 d of age, Holstein bulls received either a high-energy diet (HE;n = 9; targeted ADG 1.5 kg/d) or a control diet (CONT;n = 10; targeted ADG 0.75 kg/d). Thereafter, all bulls were fed a similar diet. The HE treatment increased LH secretion at 125 d of age, testosterone concentrations from 181 to 210 d, and scrotal circumference (SC) from 146 to 360 d of age relative to the CONT treatment. Beginning at 241 ± 5 d of age, semen collection (artificial vagina) was attempted every 14 d in bulls from the HE (n = 8) and CONT (n = 7) treatment until each bull attained puberty (ejaculate containing 50 × 10 spermatozoa with 10% motility). To assess semen production as mature bulls, semen was collected thrice weekly beginning at 541 ± 5 d of age until slaughter at 569 ± 5 d of age. After slaughter, epididymal and testicular measurements were collected and testicular tissue was fixed to determine seminiferous tubule diameter. Age at puberty did not differ between treatments (310 ± 35 d). Although testis and epididymal weight and testis volume were greater (P < 0.05) in the HE than the CONT treatment, sperm production of mature bulls did not differ between treatments. Diameter of seminiferous tubules also did not differ between treatments. We conclude that the HE advanced aspects of sexual maturation and increased testes size, but this was not reflected in hastened puberty or sperm production in the present

  20. Estimation of the optimal timing of fertilization for embryo development of in vitro-matured bovine oocytes based on the times of nuclear maturation and sperm penetration.

    PubMed

    Koyama, Keisuke; Kang, Sung-Sik; Huang, Weiping; Yanagawa, Yojiro; Takahashi, Yoshiyuki; Nagano, Masashi

    2014-05-01

    The objective of this research was to estimate the optimal timing for fertilization to achieve proper embryonic development of in vitro-matured bovine oocytes. First, cumulus-oocyte complexes were subjected to in vitro maturation (IVM) for 14-22 hr. The timing when 50% of oocytes reached metaphase II stage was estimated to be 17.5 hr after IVM start. Next, using oocytes subjected to IVM for 12-30 hr, sperm penetration was examined after 4-18 hr of in vitro fertilization (IVF). A significant negative correlation between IVM duration and the timing when 50% of oocytes were penetrated by sperm after IVF start was observed (P<0.01). Finally, oocytes subjected to 12-30 hr of IVM were inseminated and cultured for 6 days to examine embryonic development. In the group with 22 hr of IVM, the percentages of cleaved embryos and blastocysts were the highest values in all groups. According to the regression equation describing the time from nuclear maturation to sperm penetration (x) and the percentage of blastocysts (y) (y=7.23x - 0.297x(2), P<0.01), the blastocyst rate peaked when sperm penetration occurred at 12.2 hr after achieving nuclear maturation. In conclusion, under the present IVM/IVF conditions, it was estimated that oocytes acquired their highest developmental competence at about 30 hr after IVM start, and thus, the optimal IVM duration was calculated to be about 21 hr.

  1. Lipocalin 2 binds to membrane phosphatidylethanolamine to induce lipid raft movement in a PKA-dependent manner and modulates sperm maturation.

    PubMed

    Watanabe, Hitomi; Takeo, Toru; Tojo, Hiromasa; Sakoh, Kazuhito; Berger, Thorsten; Nakagata, Naomi; Mak, Tak W; Kondoh, Gen

    2014-05-01

    Mammalian sperm undergo multiple maturation steps after leaving the testis in order to become competent for fertilization, but the molecular mechanisms underlying this process remain unclear. In terms of identifying factors crucial for these processes in vivo, we found that lipocalin 2 (Lcn2), which is known as an innate immune factor inhibiting bacterial and malarial growth, can modulate sperm maturation. Most sperm that migrated to the oviduct of wild-type females underwent lipid raft reorganization and glycosylphosphatidylinositol-anchored protein shedding, which are signatures of sperm maturation, but few did so in Lcn2 null mice. Furthermore, we found that LCN2 binds to membrane phosphatidylethanolamine to reinforce lipid raft reorganization via a PKA-dependent mechanism and promotes sperm to acquire fertility by facilitating cholesterol efflux. These observations imply that mammals possess a mode for sperm maturation in addition to the albumin-mediated pathway.

  2. Development of porcine embryos and offspring after intracytoplasmic sperm injection with liposome transfected or non-transfected sperm into in vitro matured oocytes.

    PubMed

    Lai, L; Sun, Q; Wu, G; Murphy, C N; Kühholzer, B; Park, K W; Bonk, A J; Day, B N; Prather, R S

    2001-11-01

    The objective of this study was to evaluate in vitro and in vivo development of porcine in vitro matured (IVM) porcine oocytes fertilised by intracytoplasmic sperm injection (ICSI) and the possibility of producing transgenic embryos and offspring with this procedure. Activated ICSI oocytes had a higher pronuclear formation than non-activated ICSI oocytes (mean 64.8+/-17.3% vs 28.5+/-3.4%, p<0.05). When the zygotes with two pronuclei were cultured to day 2, there was no difference (p<0.05) in the cleavage rate (mean 60.0+/-7.0% vs 63.3+/-12.7%) between the two groups. The blastocyst rate in the activation group was significantly higher than that in the non-activation group (mean 30.0+/-11.6% vs 4.6+/-4.2%, p<0.05). After injection of the sperm transfected with DNA/liposome complex, destabilised enhanced green fluorescent protein (d2EGFP) expression was not observed on day 2 in either cleaved or uncleaved embryos. But from day 3, some of the embryos at the 2-cell to 4-cell stage started to express d2EGFP. On day 7, about 30% of cleaved embryos, which were in the range of 2-cell to blastocyst stage, expressed d2EGFP. However, for the IVF oocytes inseminated with sperm transfected with DNA/liposome complex, and for oocytes injected with sperm transfected with DNA/liposome complex, and for oocytes injected with DNA/liposome complex following insemination with sperm not treated with DNA/liposome complex, none of the embryos expressed d2EGFP. Sixteen day 4 ICSI embryos derived from sperm not treated with DNA/liposome complex were transferred into a day 3 recipient. One recipient delivered a female piglet with normal birthweight. After transfer of the ICSI embryos derived from sperm transfected with DNA/liposome complex, none of the four recipients maintained pregnancy. PMID:11771901

  3. Morphometric study of the testis and reproductive tract (including sperm granuloma) after vasectomy in mature rats

    PubMed Central

    Ma, Li; Guo, Yang; Yuan, Yong; Li, Yu-Gen; Deng, Xian-Zhong; Yang, Zheng-Wei

    2016-01-01

    By utilizing the rabbit model, previous studies have found good evidence indicating that vasectomy-induced spermatogenic damage is pressure-mediated: the damage occurs when the occluded reproductive tract is unable to accommodate additional spermatozoa produced by the testis. More studies with the more commonly used rat model have shown, however, controversial results on whether and why the damage occurs. In this study, 12 mature male Sprague-Dawley rats were subjected to unilateral vasectomy: double ligation (without severing) of the vas deferens exposed via a small inguinal incision; 37 days after the operation, the testes, epididymides, vasa deferentia (juxta-epididymal segments), and sperm granulomas (at the vasectomy site) were removed to obtain methacrylate resin-embedded sections and morphometric studies carried out with light microscopy. Marked spermatogenic damage with spermatids and spermatocytes depleted in the seminiferous epithelium in 43% of the seminiferous tubule profiles was demonstrated in 5 of the 12 testes on the vasectomized side, and the damage was associated with smaller or absent sperm granulomas; in the other 7 testes with essentially normal spermatogenesis, there was an increase (by 111% on average) in the volume of the tubule lumen, associated with larger granulomas or granulomas containing more spermatozoa. There was an overall increase (by 66%) in the thickness of the rete testis in the 12 testes; the epididymis or vas deferens showed no distension. It seems therefore that the spermatogenic damage induced by vasectomy in rats is pressure-mediated as well, and that variation in the damage depends mainly on the postoperative development of the sperm granuloma. PMID:25791731

  4. Bovine in vitro fertilization: in vitro oocyte maturation and sperm capacitation with heparin.

    PubMed

    Parrish, John J

    2014-01-01

    As a result of research in the 1980s on in vitro maturation, sperm capacitation, and in vitro fertilization, the bovine is now one of the important models for development. Further, the current production of bovine embryos in vitro rivals that of in vivo embryo production for commercial applications. Researchers of today may be unaware of why decisions were made in the procedures. This review addresses the state of the art at the time of the work by Parrish et al. (Bovine in vitro fertilization with frozen thawed semen. Theriogenology 1986;25:591-600), and how later work would explain success or failure of competing procedures. Important was the use of frozen semen and heparin capacitation, because this allowed future researchers/practitioners to change sperm numbers and capacitation conditions to adjust for variations among bulls. The large numbers of citation of the original work stand the testament of time in the repeatability and success of the procedures. The work was done within the environment of the N.L. First laboratory and the unique interactions with a large number of talented graduate students, postdoctoral researchers, and technicians.

  5. The presence of centrioles and centrosomes in ovarian mature cystic teratoma cells suggests human parthenotes developed in vitro can differentiate into mature cells without a sperm centriole

    SciTech Connect

    Lee, Bo Yon; Shim, Sang Woo; Kim, Young Sun; Kim, Seung Bo

    2011-11-18

    Highlights: Black-Right-Pointing-Pointer The sperm centriole is the progenitor of centrosomes in all somatic cells. Black-Right-Pointing-Pointer Centrioles and centrosomes exist in parthenogenetic ovarian teratoma cells. Black-Right-Pointing-Pointer Without a sperm centriole, parthenogenetic oocytes produce centrioles and centrosomes. Black-Right-Pointing-Pointer Parthenogenetic human oocytes can develop and differentiate into mature cells. -- Abstract: In most animals, somatic cell centrosomes are inherited from the centriole of the fertilizing spermatozoa. The oocyte centriole degenerates during oogenesis, and completely disappears in metaphase II. Therefore, the embryos generated by in vitro parthenogenesis are supposed to develop without any centrioles. Exceptional acentriolar and/or acentrosomal developments are possible in mice and in some experimental cells; however, in most animals, the full developmental potential of parthenogenetic cells in vitro and the fate of their centrioles/centrosomes are not clearly understood. To predict the future of in vitro human parthenogenesis, we explored the centrioles/centrosomes in ovarian mature cystic teratoma cells by immunofluorescent staining and transmission electron microscopy. We confirmed the presence of centrioles and centrosomes in these well-known parthenogenetic ovarian tumor cells. Our findings clearly demonstrate that, even without a sperm centriole, parthenotes that develop from activated oocytes can produce their own centrioles/centrosomes, and can even develop into the well-differentiated mature tissue.

  6. Hypotonic resistance of boar spermatozoa: sperm subpopulations and relationship with epididymal maturation and fertility.

    PubMed

    Druart, Xavier; Gatti, Jean-Luc; Huet, Sylvie; Dacheux, Jean-Louis; Humblot, Patrice

    2009-02-01

    Hypotonic resistance of boar spermatozoa was investigated by measuring the ratio of live/dead spermatozoa (SYBR-14/propidium iodide) by flow cytometry after hypotonic stress. The survival rate of ejaculated spermatozoa incubated in hypotonic solutions ranging from 3 to 330 mmol/kg followed a sigmoid curve that fitted a simple logistic model. The critical osmolality value (Osm(crit)) at which 50% of spermatozoa died was determined with this model. Hypotonic resistance of spermatozoa increased with temperature between 15 and 39 degrees C and decreased after hydrogen superoxide treatment, but was not modified during 8 days of preservation in Beltsville thawing solution. Hypotonic resistance markedly decreased during epididymal maturation and after ejaculation as Osm(crit) at 15 degrees C was 54.7+/-3.2, 68.5+/-10.6, 116.7+/-2.1 and 194.3+/-3.7 mmol/kg for the caput, corpus, cauda and ejaculated spermatozoa respectively. Hypo-osmotic stress of 100 mmol/kg revealed a sperm subpopulation exhibiting increased hypotonic resistance compared with the whole ejaculate (Osm(crit)=67.8+/-2.1 mmol/kg). Consistent differences were observed between lean and standard breeds (Pietrain versus Large White) and between boars within the same breed. According to data collected by artificial insemination centers during a large-scale field trial, hypotonic resistance of ejaculates was found to be positively correlated with in vivo fertility. PMID:18996973

  7. The Glycosylphosphatidylinositol-Anchored Serine Protease PRSS21 (Testisin) Imparts Murine Epididymal Sperm Cell Maturation and Fertilizing Ability1

    PubMed Central

    Netzel-Arnett, Sarah; Bugge, Thomas H.; Hess, Rex A.; Carnes, Kay; Stringer, Brett W.; Scarman, Anthony L.; Hooper, John D.; Tonks, Ian D.; Kay, Graham F.; Antalis, Toni M.

    2009-01-01

    An estimated 25%–40% of infertile men have idiopathic infertility associated with deficient sperm numbers and quality. Here, we identify the membrane-anchored serine protease PRSS21, also known as testisin, to be a novel proteolytic factor that directs epididymal sperm cell maturation and sperm-fertilizing ability. PRSS21-deficient spermatozoa show decreased motility, angulated and curled tails, fragile necks, and dramatically increased susceptibility to decapitation. These defects reflect aberrant maturation during passage through the epididymis, because histological and electron microscopic structural analyses showed an increased tendency for curled and detached tails as spermatozoa transit from the corpus to the cauda epididymis. Cauda epididymal spermatozoa deficient in PRSS21 fail to mount a swelling response when exposed to hypotonic conditions, suggesting an impaired ability to respond to osmotic challenges facing maturing spermatozoa in the female reproductive tract. These data suggest that aberrant regulation of PRSS21 may underlie certain secondary male infertility syndromes, such as “easily decapitated” spermatozoa in humans. PMID:19571264

  8. Can the rapid identification of mature spermatozoa during microdissection testicular sperm extraction guide operative planning?

    PubMed

    Alrabeeah, K; Doucet, R; Boulet, E; Phillips, S; Al-Hathal, N; Bissonnette, F; Kadoch, I J; Zini, A

    2015-05-01

    The minimum sperm count and quality that must be identified during microdissection testicular sperm extraction (micro-TESE) to deem the procedure successful remains to be established. We conducted a retrospective study of 81 consecutive men with non-obstructive azoospermia who underwent a primary (first) micro-TESE between March 2007 and October 2013. Final assessment of sperm recovery [reported on the day of (intracytoplasmic sperm injection) ICSI] was recorded as (i) successful (available spermatozoa for ICSI) or (ii) unsuccessful (no spermatozoa for ICSI). The decision to perform a unilateral (with limited or complete microdissection) or bilateral micro-TESE was guided by the intra-operative identification of sperm recovery (≥5 motile or non-motile sperm) from the first testicle. Overall, sperm recovery was successful in 56% (45/81) of the men. A unilateral micro-TESE was performed in 47% (38/81) of the men (based on intra-operative identification of sperm) and in 100% (38/38) of these men, spermatozoa was found on final assessment. In 42% (16/38) of the unilateral cases, a limited microdissection was performed (owing to the rapid intra-operative identification of sperm). The remaining 43 men underwent a bilateral micro-TESE and 16% (7/43) of these men had sperm identified on final assessment. The cumulative ICSI pregnancy rates (per cycle started and per embryo transfer) were 47% (21/45) and 60% (21/35), respectively, with a mean (±SD) of 1.9 ± 1.0 embryos transferred. The data demonstrate that intra-operative assessment of sperm recovery can correctly identify those men that require a unilateral micro-TESE. Moreover, the rapid identification of sperm recovery can allow some men to undergo a limited unilateral micro-TESE and avoid the need for complete testicular microdissection.

  9. The microRNA signature of mouse spermatozoa is substantially modified during epididymal maturation.

    PubMed

    Nixon, Brett; Stanger, Simone J; Mihalas, Bettina P; Reilly, Jackson N; Anderson, Amanda L; Tyagi, Sonika; Holt, Janet E; McLaughlin, Eileen A

    2015-10-01

    In recent years considerable effort has been devoted to understanding the epigenetic control of sperm development, leading to an increased appreciation of the importance of RNA interference pathways, and in particular miRNAs, as key regulators of spermatogenesis and epididymal maturation. It has also been shown that sperm are endowed with an impressive array of miRNA that have been implicated in various aspects of fertilization and embryo development. However, to date there have been no reports on whether the sperm miRNA signature is static or whether it is influenced by their prolonged maturation within the male reproductive tract. To investigate this phenomenon, we employed next-generation sequencing to systematically profile the miRNA signature of maturing mouse spermatozoa. In so doing we have provided the first evidence for the posttesticular modification of the sperm miRNA profile under normal physiological conditions. Such modifications include the apparent loss and acquisition of an impressive cohort of some 113 and 115 miRNAs, respectively, between the proximal and distal epididymal segments. Interestingly, the majority of these changes occur late in maturation and include the uptake of novel miRNA species in addition to a significant increase in many miRNAs natively expressed in immature sperm. Because sperm are not capable of de novo transcription, these findings identify the epididymis as an important site in establishing the sperm epigenome with the potential to influence the peri-conceptual environment of the female reproductive tract, contribute to the inheritance of acquired characteristics, and/or alter the developmental trajectory of the resulting offspring. PMID:26333995

  10. Changes in Carboxy Methylation and Tyrosine Phosphorylation of Protein Phosphatase PP2A Are Associated with Epididymal Sperm Maturation and Motility.

    PubMed

    Dudiki, Tejasvi; Kadunganattil, Suraj; Ferrara, John K; Kline, Douglas W; Vijayaraghavan, Srinivasan

    2015-01-01

    Mammalian sperm contain the serine/threonine phosphatases PP1γ2 and PP2A. The role of sperm PP1γ2 is relatively well studied. Here we confirm the presence of PP2A in sperm and show that it undergoes marked changes in methylation (leucine 309), tyrosine phosphorylation (tyrosine 307) and catalytic activity during epididymal sperm maturation. Spermatozoa isolated from proximal caput, distal caput and caudal regions of the epididymis contain equal immuno-reactive amounts of PP2A. Using demethyl sensitive antibodies we show that PP2A is methylated at its carboxy terminus in sperm from the distal caput and caudal regions but not in sperm from the proximal caput region of the epididymis. The methylation status of PP2A was confirmed by isolation of PP2A with microcystin agarose followed by alkali treatment, which causes hydrolysis of protein carboxy methyl esters. Tyrosine phosphorylation of sperm PP2A varied inversely with methylation. That is, PP2A was tyrosine phosphorylated when it was demethylated but not when methylated. PP2A demethylation and its reciprocal tyrosine phosphorylation were also affected by treatment of sperm with L-homocysteine and adenosine, which are known to elevate intracellular S-adenosylhomocysteine, a feedback inhibitor of methyltransferases. Catalytic activity of PP2A declined during epididymal sperm maturation. Inhibition of PP2A by okadaic acid or by incubation of caudal epididymal spermatozoa with L-homocysteine and adenosine resulted in increase of sperm motility parameters including percent motility, velocity, and lateral head amplitude. Demethylation or pharmacological inhibition of PP2A also leads to an increase in phosphorylation of glycogen synthase kinase-3 (GSK3). Our results show for the first time that changes in PP2A activity due to methylation and tyrosine phosphorylation occur in sperm and that these changes may play an important role in the regulation of sperm function. PMID:26569399

  11. The presence of centrioles and centrosomes in ovarian mature cystic teratoma cells suggests human parthenotes developed in vitro can differentiate into mature cells without a sperm centriole.

    PubMed

    Lee, Bo Yon; Shim, Sang Woo; Kim, Young Sun; Kim, Seung Bo

    2011-11-18

    In most animals, somatic cell centrosomes are inherited from the centriole of the fertilizing spermatozoa. The oocyte centriole degenerates during oogenesis, and completely disappears in metaphase II. Therefore, the embryos generated by in vitro parthenogenesis are supposed to develop without any centrioles. Exceptional acentriolar and/or acentrosomal developments are possible in mice and in some experimental cells; however, in most animals, the full developmental potential of parthenogenetic cells in vitro and the fate of their centrioles/centrosomes are not clearly understood. To predict the future of in vitro human parthenogenesis, we explored the centrioles/centrosomes in ovarian mature cystic teratoma cells by immunofluorescent staining and transmission electron microscopy. We confirmed the presence of centrioles and centrosomes in these well-known parthenogenetic ovarian tumor cells. Our findings clearly demonstrate that, even without a sperm centriole, parthenotes that develop from activated oocytes can produce their own centrioles/centrosomes, and can even develop into the well-differentiated mature tissue.

  12. Merlin Isoforms 1 and 2 Both Act as Tumour Suppressors and Are Required for Optimal Sperm Maturation

    PubMed Central

    Zoch, Ansgar; Mayerl, Steffen; Schulz, Alexander; Greither, Thomas; Frappart, Lucien; Rübsam, Juliane; Heuer, Heike; Giovannini, Marco; Morrison, Helen

    2015-01-01

    The tumour suppressor Merlin, encoded by the gene NF2, is frequently mutated in the autosomal dominant disorder neurofibromatosis type II, characterised primarily by the development of schwannoma and other glial cell tumours. However, NF2 is expressed in virtually all analysed human and rodent organs, and its deletion in mice causes early embryonic lethality. Additionally, NF2 encodes for two major isoforms of Merlin of unknown functionality. Specifically, the tumour suppressor potential of isoform 2 remains controversial. In this study, we used Nf2 isoform-specific knockout mouse models to analyse the function of each isoform during development and organ homeostasis. We found that both isoforms carry full tumour suppressor functionality and can completely compensate the loss of the other isoform during development and in most adult organs. Surprisingly, we discovered that spermatogenesis is strictly dependent on the presence of both isoforms. While the testis primarily expresses isoform 1, we noticed an enrichment of isoform 2 in spermatogonial stem cells. Deletion of either isoform was found to cause decreased sperm quality as observed by maturation defects and head/midpiece abnormalities. These defects led to impaired sperm functionality as assessed by decreased sperm capacitation. Thus, we describe spermatogenesis as a new Nf2-dependent process. Additionally, we provide for the first time in vivo evidence for equal tumour suppressor potentials of Merlin isoform 1 and isoform 2. PMID:26258444

  13. Birth after human chorionic gonadotropin-primed oocyte in vitro maturation and fertilization with testicular sperm in a normo-ovulatory patient

    PubMed Central

    González-Ortega, Claudia; Piña-Aguilar, Raul Eduardo; Cancino-Villareal, Patricia; Gutiérrez-Gutiérrez, Antonio Martin

    2016-01-01

    In this report, we present a case of in vitro maturation (IVM) with surgical retrieved testicular sperm in a normo-ovulatory female. Human chorionic gonadotropin-primed IVM, testicular biopsy for sperm retrieval and intracytoplasmic sperm injection with fresh sperm were performed. Fourteen cumulus-oocyte complexes were obtained in germinal vesicle or metaphase I stage, eight oocytes reached metaphase II, seven presumptive zygotes were obtained, and three cleavage stages embryos in day 2 were transferred producing a singleton pregnancy. A single healthy newborn was obtained. Our results suggest that IVM may be an alternative for in vitro fertilization in normo-ovulatory women even if surgical retrieval of sperm is needed. Further research is required to depict contributing factors to the success of IVM in indications different from polycystic ovaries syndrome and the role of male gamete. PMID:27803591

  14. In vitro maturation and intracytoplasmic sperm injection of oocytes collected from hormonally stimulated common wombats, Vombatus ursinus.

    PubMed

    West, M; Lacham-Kaplan, O; Cleary, M; Galloway, D; Shaw, J; Trounson, A O; Paris, M C J

    2007-04-01

    Porcine FSH/LH stimulation successfully induced development of multiple large (>or=4mm) antral follicles in 10 of 11 common wombats. A mean of 5.5 metaphase II (MII) oocytes were aspirated from wombats that were stimulated during the follicular phase of the oestrous cycle (n=3) or after pouch young removal (n=3). Three subadults (n=3) and two anoestrus adults did not produce MII oocytes despite pFSH/pLH administration. In vitro maturation of immature oocytes at the time of aspiration doubled the number of MII oocytes that could be collected from pFSH/pLH stimulated wombats. Immature oocytes with cumulus attached, matured more readily to the MII stage than immature oocytes without cumulus. Following intracytoplasmic sperm injection (ICSI), approximately 5% of the oocytes that were MII at the time of collection cleaved. Approximately 5% of those that were matured by in vitro maturation (IVM) formed two polar bodies following ICSI, although they not cleave. Parthenogenesis cannot be excluded. This demonstrates that assisted reproductive technologies may be applicable to the common wombat. PMID:16644150

  15. In vitro maturation and intracytoplasmic sperm injection of oocytes collected from hormonally stimulated common wombats, Vombatus ursinus.

    PubMed

    West, M; Lacham-Kaplan, O; Cleary, M; Galloway, D; Shaw, J; Trounson, A O; Paris, M C J

    2007-04-01

    Porcine FSH/LH stimulation successfully induced development of multiple large (>or=4mm) antral follicles in 10 of 11 common wombats. A mean of 5.5 metaphase II (MII) oocytes were aspirated from wombats that were stimulated during the follicular phase of the oestrous cycle (n=3) or after pouch young removal (n=3). Three subadults (n=3) and two anoestrus adults did not produce MII oocytes despite pFSH/pLH administration. In vitro maturation of immature oocytes at the time of aspiration doubled the number of MII oocytes that could be collected from pFSH/pLH stimulated wombats. Immature oocytes with cumulus attached, matured more readily to the MII stage than immature oocytes without cumulus. Following intracytoplasmic sperm injection (ICSI), approximately 5% of the oocytes that were MII at the time of collection cleaved. Approximately 5% of those that were matured by in vitro maturation (IVM) formed two polar bodies following ICSI, although they not cleave. Parthenogenesis cannot be excluded. This demonstrates that assisted reproductive technologies may be applicable to the common wombat.

  16. Di-(2-ethylhexyl)-phthalate disrupts pituitary and testicular hormonal functions to reduce sperm quality in mature goldfish.

    PubMed

    Golshan, Mahdi; Hatef, Azadeh; Socha, Magdalena; Milla, Sylvain; Butts, Ian A E; Carnevali, Oliana; Rodina, Marek; Sokołowska-Mikołajczyk, Mirosława; Fontaine, Pascal; Linhart, Otomar; Alavi, Sayyed Mohammad Hadi

    2015-06-01

    Di-(2-ethylhexyl) phthalate (DEHP) interferes with male reproductive endocrine system in mammals, however its effects on fish reproduction are largely unknown. We evaluated sperm quality and investigated reproductive endocrine system in mature goldfish (Carassius auratus) exposed to nominal 1, 10, and 100μg/L DEHP. To examine DEHP estrogenic activity, one group of goldfish was exposed to 17β-estradiol (5μg/L E2) for comparison. Following 30d of exposure, sperm production was decreased and suppressed in DEHP and E2 treated goldfish, respectively. Sperm motility and velocity were decreased in goldfish exposed to 100 and 10μg/L DEHP at 15s post-sperm activation, respectively. Compared to control, 11-ketotestosterone (11-KT) levels were decreased at 10 and 1μg/L DEHP at day 15 and 30, respectively. In E2 treated goldfish, 11-KT levels were decreased compared to control during the period of exposure. E2 levels were increased in goldfish exposed to E2, but remained unchanged in DEHP treated goldfish during the period of exposure. StAR mRNA levels encoding regulator of cholesterol transfer to steroidogenesis were decreased in DEHP and E2 treated goldfish following 15 and 30d of exposure, respectively. Luteinizing hormone (LH) levels were decreased in DEHP and E2 treated goldfish following 15 and 30d of exposure, respectively. In DEHP treated goldfish, gnrh3, kiss1 and its receptor (gpr54) mRNA levels did not change during the experimental period. In E2 treated goldfish, gnrh3 mRNA levels were decreased at day 7, but kiss1 and gpr54 mRNA levels were increased at day 30 of exposure. The mRNA levels of genes encoding testicular LH and androgen receptors remained unchanged in DEHP and E2 treated goldfish. In contrast to E2 treated goldfish, vitellogenin production was not induced in DEHP treated goldfish and mRNA levels of genes with products mediating estrogenic effects remained unchanged or decreased. In conclusion, DEHP interferes with testis and pituitary hormonal

  17. Characterisation of mouse epididymosomes reveals a complex profile of microRNAs and a potential mechanism for modification of the sperm epigenome.

    PubMed

    Reilly, Jackson N; McLaughlin, Eileen A; Stanger, Simone J; Anderson, Amanda L; Hutcheon, Kate; Church, Kiralee; Mihalas, Bettina P; Tyagi, Sonika; Holt, Janet E; Eamens, Andrew L; Nixon, Brett

    2016-01-01

    Recent evidence has shown that the sperm epigenome is vulnerable to dynamic modifications arising from a variety of paternal environment exposures and that this legacy can serve as an important determinant of intergenerational inheritance. It has been postulated that such exchange is communicated to maturing spermatozoa via the transfer of small non-protein-coding RNAs (sRNAs) in a mechanism mediated by epididymosomes; small membrane bound vesicles released by the soma of the male reproductive tract (epididymis). Here we confirm that mouse epididymosomes encapsulate an impressive cargo of >350 microRNAs (miRNAs), a developmentally important sRNA class, the majority (~60%) of which are also represented by the miRNA signature of spermatozoa. This includes >50 miRNAs that were found exclusively in epididymal sperm and epididymosomes, but not in the surrounding soma. We also documented substantial changes in the epididymosome miRNA cargo, including significant fold changes in almost half of the miRNAs along the length of the epididymis. Finally, we provide the first direct evidence for the transfer of several prominent miRNA species between mouse epididymosomes and spermatozoa to afford novel insight into a mechanism of intercellular communication by which the sRNA payload of sperm can be selectively modified during their post-testicular maturation. PMID:27549865

  18. Characterisation of mouse epididymosomes reveals a complex profile of microRNAs and a potential mechanism for modification of the sperm epigenome

    PubMed Central

    Reilly, Jackson N.; McLaughlin, Eileen A.; Stanger, Simone J.; Anderson, Amanda L.; Hutcheon, Kate; Church, Kiralee; Mihalas, Bettina P.; Tyagi, Sonika; Holt, Janet E.; Eamens, Andrew L.; Nixon, Brett

    2016-01-01

    Recent evidence has shown that the sperm epigenome is vulnerable to dynamic modifications arising from a variety of paternal environment exposures and that this legacy can serve as an important determinant of intergenerational inheritance. It has been postulated that such exchange is communicated to maturing spermatozoa via the transfer of small non-protein-coding RNAs (sRNAs) in a mechanism mediated by epididymosomes; small membrane bound vesicles released by the soma of the male reproductive tract (epididymis). Here we confirm that mouse epididymosomes encapsulate an impressive cargo of >350 microRNAs (miRNAs), a developmentally important sRNA class, the majority (~60%) of which are also represented by the miRNA signature of spermatozoa. This includes >50 miRNAs that were found exclusively in epididymal sperm and epididymosomes, but not in the surrounding soma. We also documented substantial changes in the epididymosome miRNA cargo, including significant fold changes in almost half of the miRNAs along the length of the epididymis. Finally, we provide the first direct evidence for the transfer of several prominent miRNA species between mouse epididymosomes and spermatozoa to afford novel insight into a mechanism of intercellular communication by which the sRNA payload of sperm can be selectively modified during their post-testicular maturation. PMID:27549865

  19. Plasma membrane Ca2+-ATPase 4 in murine epididymis: secretion of splice variants in the luminal fluid and a role in sperm maturation.

    PubMed

    Patel, Ramkrishna; Al-Dossary, Amal A; Stabley, Deborah L; Barone, Carol; Galileo, Deni S; Strehler, Emanuel E; Martin-DeLeon, Patricia A

    2013-07-01

    Plasma membrane Ca(2+)-ATPase isoform 4 (PMCA4) is the primary Ca(2+) efflux pump in murine sperm, where it regulates motility. In Pmca4 null sperm, motility loss results in infertility. We have shown that murine sperm PMCA4b interacts with Ca(2+)/CaM-dependent serine kinase (CASK) in regulating Ca(2+) homeostasis and motility. However, recent work indicated that the bovine PMCA4a splice variant (missing in testis) is epididymally expressed, along with 4b, and may be transferred to sperm. Here we show, via conventional and in situ RT-PCR, that both the splice variants of Pmca4 mRNA are expressed in murine testis and throughout the epididymis. Immunofluorescence localized PMCA4a to the apical membrane of the epididymal epithelium, and Western analysis not only confirmed its presence but showed for the first time that PMCA4a and PMCA4b are secreted in the epididymal luminal fluid (ELF), from which epididymosomes containing PMCA4a were isolated. Flow cytometry indicated the presence of PMCA4a on mature caudal sperm where it was increased ~5-fold compared to caput sperm (detected by Western blotting) and ~2-fold after incubation in ELF, revealing in vitro uptake and implicating PMCA4a in epididymal sperm maturation. Coimmunoprecipitation using pan-PMCA4 antibodies, revealed that both variants associate with CASK, suggesting their presence in a complex. Because they have different kinetic properties for Ca(2+) transport and different abilities to bind to CASK, our study suggests a mechanism for combining the functional attributes of both PMCA4 variants, leading to heightened efficiency of the pump in the maintenance of Ca(2+) homeostasis, which is crucial for normal motility and male fertility.

  20. Production of lion (Panthera leo) blastocysts after in vitro maturation of oocytes and intracytoplasmic sperm injection.

    PubMed

    Fernandez-Gonzalez, Lorena; Hribal, Romy; Stagegaard, Julia; Zahmel, Jennifer; Jewgenow, Katarina

    2015-04-01

    Assisted reproductive techniques are becoming widely applied to the breeding of endangered species, but establishing reliable protocols for the production of embryos in vitro is challenging because of the scarcity of sample material. In our study, we applied an assisted reproductive technique protocol for IVM and intracytoplasmic sperm injection (ICSI), developed in the domestic cat, to oocytes retrieved from ovaries of four 2-year-old lionesses (Panthera leo) eight hours postmortem. In total, 68 cumulus-oocyte complexes of good quality were randomly distributed and cultured for 32 to 34 hours in two different maturation culture media, consisting of Medium 199 with Earle's salts, 3 mg/mL BSA, 0.1 mg/mL cysteine, 1.4 mg/mL sodium pyruvate, 0.6 mg/mL sodium lactate, 0.15 mg/mL l-glutamine, and 0.055 mg/mL gentamicin. Hormonal supplementation of IVM_1 was 0.02 IU/mL FSH and 0.05 IU/mL LH; IVM_2 consisted of 1.64 IU/mL FSH, 1.06 IU/mL LH, and 1 μg/mL 17ß-estradiol. Differences in hormonal supplementation did not produce significant differences in oocyte maturation rates, which were 39.4% in IVM_1 and 34.3% in IVM_2. Matured oocytes were microinjected with homologous frozen-thawed spermatozoa, and subsequent cleavage rates were 30.8% and 58.3%, respectively. Half of the embryos derived from oocytes matured in IVM_1 developed into blastocysts, whereas only 28.6% of embryos from oocytes matured in IVM_2 reached the blastocyst stage. Morula stages were present from Day 6 onward, and blastocyst stages from Day 9 on, indicating a slower developmental speed in comparison with domestic cats. This is the first report of in vitro-produced blastocysts using ICSI in the lion, and the results report that IVM and ICSI can be successfully performed with cumulus-oocyte complexes retrieved from ovaries after eight hours of shipping, obtaining competent embryos in culture.

  1. Spermatogenesis in the blue swimming crab, Portunus pelagicus, and evidence for histones in mature sperm nuclei.

    PubMed

    Stewart, Michael J; Stewart, Praphaporn; Soonklang, Nantawan; Linthong, Vichai; Hanna, Peter J; Duan, Wei; Sobhon, Prasert

    2010-06-01

    Spermatogenesis in the blue swimming crab, Portunus pelagicus, is described by light and electron microscopy. The testis is composed of anterior (AT) and posterior (PT) lobes, that are partitioned into lobules by connective tissue trabecula, and further divided into zones (germinal, transformation and evacuation), each with various stages of cellular differentiation. The vas deferens is classified into three distinct regions: anterior (AVD), median (MVD), and posterior (PVD), on the presence of spermatophores and two secretions, termed substance I and II. Based on the degree and patterns of heterochromatin, spermatogenesis is classified into 13 stages: two spermatogonia (SgA and SgB), six primary spermatocytes (leptotene, zygotene, pachytene, diplotene, diakinesis, and metaphase), a secondary spermatocyte (SSc), three spermatids (St 1-3), and a mature spermatozoon. Spermatid stages are differentiated by chromatin decondensation and the formation of an acrosomal complex, which is unique to brachyurans. Mature spermatozoa are aflagellated, and have a nuclear projection and a spherical acrosome. AUT-PAGE and Western blots show that, during chromatin decondensation, there is a reduction of most histones, with only small amounts of H2B and H3 remaining in mature spermatozoa.

  2. Identification and Characterization of a Novel Non-Coding RNA Involved in Sperm Maturation

    PubMed Central

    Ni, Min-Jie; Hu, Zhi-Hong; Liu, Qiang; Liu, Mo-Fang; Lu, Min-hua; Zhang, Jin-Song; Zhang, Li; Zhang, Yong-Lian

    2011-01-01

    A long and ever-expanding roster of small (∼20–30 nucleotides) RNAs has emerged during the last decade, and most can be subsumed under the three main headings of microRNAs(miRNAs), Piwi-interacting RNAs(piRNAs), and short interferingRNAs(siRNAs). Among the three categories, miRNAs is the most quickly expanded group. The most recent number of identified miRNAs is 16,772 (Sanger miRbase, April 2011). However, there are insufficient publications on their primary forms, and no tissue-specific small RNAs precursors have been reported in the epididymis. Here, we report the identification in rats of an epididymis-specific, chimeric, noncoding RNA that is spliced from two different chromosomes (chromosomes 5 and 19), which we named HongrES2. HongrES2 is a 1.6 kb mRNA-like precursor that gives rise to a new microRNA-like small RNA (mil-HongrES2) in rat epididymis. The generation of mil-HongrES2 is stimulated during epididymitis. An epididymis-specific carboxylesterase named CES7 had 100% cDNA sequence homology at the 3′end with HongrES2 and its protein product could be downregulated by HongrES2 via mil-HongrES2. This was confirmed in vivo by initiating mil-HongrES2 over-expression in rats and observing an effect on sperm capacitation. PMID:22022505

  3. Porcine embryo production following in vitro fertilization and intracytoplasmic sperm injection from vitrified immature oocytes matured with a granulosa cell co-culture system.

    PubMed

    Casillas, Fahiel; Ducolomb, Yvonne; Lemus, Ana E; Cuello, Cristina; Betancourt, Miguel

    2015-10-01

    This study was designed to evaluate the capacity of vitrified-warmed porcine immature oocytes to mature and to be fertilized using in vitro fertilization or intracytoplasmic sperm injection, and to determine the subsequent embryo development. Immature oocytes were vitrified using ethylene glycol and dimethylsulphoxide as cryoprotectants and the Cryolock method. After warming oocytes were cultured 44 h for maturation. Oocytes were randomly distributed in three treatment groups and subjected to in vitro fertilization (Experiment 1) or intracytoplasmic sperm injection (Experiment 2) procedures. The results indicate that the embryo development was higher in denuded oocytes co-cultured with granulosa cells (NkO-CC group) fertilized by in vitro fertilization or intracytoplasmic sperm injection compared to cumulus-cell oocyte complexes (COCs group), showing no significant differences with control. Vitrified denuded oocytes matured with a co-culture system NkO-CC group, displayed higher cleavage rate and blastocyst production than vitrified COCs group. Blastocysts were successfully obtained after IVF and ICSI procedures; however, the development to the blastocyst stage was better after IVF. These results show that the vitrification-warming media, the employment of a granulosa cell co-culture system and the Cryolock method during vitrification, increased the nuclear and cytoplasmic maturation of vitrified porcine immature oocytes. Further experiments are required to enhance porcine embryo production after vitrification.

  4. Manipulation and In Vitro Maturation of Xenopus laevis Oocytes, Followed by Intracytoplasmic Sperm Injection, to Study Embryonic Development

    PubMed Central

    Miyamoto, Kei; Simpson, David; Gurdon, John B.

    2015-01-01

    Amphibian eggs have been widely used to study embryonic development. Early embryonic development is driven by maternally stored factors accumulated during oogenesis. In order to study roles of such maternal factors in early embryonic development, it is desirable to manipulate their functions from the very beginning of embryonic development. Conventional ways of gene interference are achieved by injection of antisense oligonucleotides (oligos) or mRNA into fertilized eggs, enabling under- or over-expression of specific proteins, respectively. However, these methods normally require more than several hours until protein expression is affected, and, hence, the interference of gene functions is not effective during early embryonic stages. Here, we introduce an experimental system in which expression levels of maternal proteins can be altered before fertilization. Xenopus laevis oocytes obtained from ovaries are defolliculated by incubating with enzymes. Antisense oligos or mRNAs are injected into defolliculated oocytes at the germinal vesicle (GV) stage. These oocytes are in vitro matured to eggs at the metaphase II (MII) stage, followed by intracytoplasmic sperm injection (ICSI). By this way, up to 10% of ICSI embryos can reach the swimming tadpole stage, thus allowing functional tests of specific gene knockdown or overexpression. This approach can be a useful way to study roles of maternally stored factors in early embryonic development. PMID:25742326

  5. Alteration of the isoform composition of plasma-membrane-associated rat sperm alpha-L-fucosidase during late epididymal maturation: comparative characterization of the acidic and neutral isoforms.

    PubMed Central

    Abascal, I; Skalaban, S R; Grimm, K M; Avilés, M; Martianez-Menarguez, J A; Castells, M T; Ballesta, J; Alhadeff, J A

    1998-01-01

    In a previous study, evidence was provided for the presence of a novel plasma-membrane-associated neutral-pH-optimum alpha-L-fucosidase in rat sperm. In the present study, rat sperm alpha-L-fucosidase was characterized during epididymal maturation. The pH 7 activity optimum of alpha-L-fucosidase and its subunit composition (one or two closely spaced immunoreactive protein bands of about 53+/-2 kDa) did not appear to change during transit through the epididymis. Isoelectric focusing of alpha-L-fucosidase indicated the presence of a major isoform (B) with a pI near 7 in sperm from testis, caput, corpus and the proximal half of the cauda. alpha-L-Fucosidase from sperm from the distal half of the cauda, which contained a significant enrichment of sperm and alpha-L-fucosidase activity, contained isoform B and an additional minor isoform (A) with a pI near 5.2. Isoform B and small amounts of isoform A were present in sperm from the vas deferens. The two fucosidase isoforms present in sperm from the distal cauda were separated by isoelectric focusing and comparatively characterized. They had similar pH-activity curves (with optima near pH 7) and comparable apparent KM values (0.4+/-0.04 mM) for 4-methylumbelliferyl alpha-l-fucopyranoside. Preincubation of the isoforms at different temperatures indicated that isoform A is considerably more thermostable than isoform B. Immunoprecipitation studies using polyclonal antibodies against human liver alpha-L-fucosidase indicated that approx. 90% of the enzymic activity for both isoforms was immunoprecipitable under conditions that immunoprecipitated essentially all the human liver enzyme. Neuraminidase treatment of sperm alpha-L-fucosidase from distal cauda (when compared with the appropriate heat-treated control) led to disappearance of isoform A and a concomitant increase in isoform B. The overall results suggest that isoform A is derived by sialylation of isoform B near the end of epididymal maturation. PMID:9639580

  6. Elucidation of the involvement of p14, a sperm protein during maturation, capacitation and acrosome reaction of caprine spermatozoa.

    PubMed

    Nandi, Pinki; Ghosh, Swatilekha; Jana, Kuladip; Sen, Parimal C

    2012-01-01

    Mammalian sperm capacitation is an essential prerequisite to fertilization. Although progress is being made in understanding the physiology and biochemistry of capacitation, little has been yet explored about the potential role(s) of individual sperm cell protein during this process. Therefore elucidation of the role of different sperm proteins in the process of capacitation might be of great importance to understand the process of fertilization. The present work describes the partial characterization of a 14-kDa protein (p14) detected in goat spermatozoa using an antibody directed against the purified protein. Confocal microscopic analysis reveals that the protein is present in both the intracellular and extracellular regions of the acrosomal and postacrosomal portion of caudal sperm head. Though subcellular localization shows that p14 is mainly cytosolic, however it is also seen to be present in peripheral plasma membrane and soluble part of acrosome. Immuno-localization experiment shows change in the distribution pattern of this protein upon induction of capacitation in sperm cells. Increased immunolabeling in the anterior head region of live spermatozoa is also observed when these cells are incubated under capacitating conditions, whereas most sperm cells challenged with the calcium ionophore A23187 to acrosome react, lose their labeling almost completely. Intracellular distribution of p14 also changes significantly during acrosome reaction. Interestingly, on the other hand the antibody raised against this 14-kDa sperm protein enhances the forward motility of caprine sperm cells. Rose-Bengal staining method shows that this anti-p14 antibody also decreases the number of acrosome reacted cells if incubated with capacitated sperm cells before induction of acrosome reaction. All these results taken together clearly indicate that p14 is intimately involved and plays a critical role in the acrosomal membrane fusion event.

  7. Alternative splicing, promoter methylation, and functional SNPs of sperm flagella 2 gene in testis and mature spermatozoa of Holstein bulls.

    PubMed

    Guo, F; Yang, B; Ju, Z H; Wang, X G; Qi, C; Zhang, Y; Wang, C F; Liu, H D; Feng, M Y; Chen, Y; Xu, Y X; Zhong, J F; Huang, J M

    2014-02-01

    The sperm flagella 2 (SPEF2) gene is essential for development of normal sperm tail and male fertility. In this study, we characterized first the splice variants, promoter and its methylation, and functional single-nucleotide polymorphisms (SNPs) of the SPEF2 gene in newborn and adult Holstein bulls. Four splice variants were identified in the testes, epididymis, sperm, heart, spleen, lungs, kidneys, and liver tissues through RT-PCR, clone sequencing, and western blot analysis. Immunohistochemistry revealed that the SPEF2 was specifically expressed in the primary spermatocytes, elongated spermatids, and round spermatids in the testes and epididymis. SPEF2-SV1 was differentially expressed in the sperms of high-performance and low-performance adult bulls; SPEF2-SV2 presents the highest expression in testis and epididymis; SPEF2-SV3 was only detected in testis and epididymis. An SNP (c.2851G>T) in exon 20 of SPEF2, located within a putative exonic splice enhancer, potentially produced SPEF2-SV3 and was involved in semen deformity rate and post-thaw cryopreserved sperm motility. The luciferase reporter and bisulfite sequencing analysis suggested that the methylation pattern of the core promoter did not significantly differ between the full-sib bulls that presented hypomethylation in the ejaculated semen and testis. This finding indicates that sperm quality is unrelated to SPEF2 methylation pattern. Our data suggest that alternative splicing, rather than methylation, is involved in the regulation of SPEF2 expression in the testes and sperm and is one of the determinants of sperm motility during bull spermatogenesis. The exonic SNP (c.2851G>T) produces aberrant splice variants, which can be used as a candidate marker for semen traits selection breeding of Holstein bulls.

  8. Attempt at intracytoplasmic sperm injection of in vitro matured oocytes in common minke whales (Balaenoptera acutorostrata) captured during the Kushiro Coast Survey.

    PubMed

    Fukui, Yutaka; Iwayama, Hiroshi; Matsuoka, Taiki; Nagai, Hiroki; Koma, Noriko; Mogoe, Toshihiro; Ishikawa, Hajime; Fujise, Yoshihiro; Hirabayashi, Masumi; Hochi, Shinichi; Kato, Hidehiro; Ohsumi, Seiji

    2007-08-01

    The present study was conducted during the Kushiro Coast Survey in an attempt to produce common minke whale embryos. In Experiment 1, we attempted to determine the appropriate culture duration (30 or 40 h) for in vitro maturation (IVM) of immature oocytes using the Well of the Well method. In Experiment 2, and intracytoplasmic sperm injection (ICSI) was applied to matured oocytes from prepubertal and adult common minke whales after IVM culture (40 or 48 h), and then their embryonic development was assessed. In Experiment 1, the maturation rate of oocytes cultured for 40 h (30.4%) was significantly higher than that of oocytes cultured for 30 h (6.8%; P<0.01). In Experiment 2, a total of 35 and 46 immature oocytes derived from adult (n=2) and prepubertal (n=6) minke whales, respectively, were cultured for 40 or 48 h. The maturation rate in the oocytes from the adult whales (34.2%) tended to be higher than that of the oocytes from the prepubertal whales (19.6%), but there was no significant difference. Following ICSI, 3 out of the 10 inseminated and cultured oocytes from the adult whales cleaved (2-, 8-, and 16-cell stages); all of these oocytes had been matured for 40 in culture. However, these oocytes did not develop to further stages. Only one of the 6 oocytes derived from the prepubertal whales, IVM cultured for 40 h and inseminated, developed to the 4-cell stage. The present results indicate that a 40 h IVM culture produces significantly higher rates of in vitro maturation than a 30 h IVM culture for common minke whale oocytes. Following ICSI, some oocytes cleaved to the 16-cell stage, but no further development was observed.

  9. In vitro maturation, fertilization, embryo development & clinical outcome of human metaphase-I oocytes retrieved from stimulated intracytoplasmic sperm injection cycles

    PubMed Central

    Álvarez, Cristina; García-Garrido, Carmen; Taronger, Roser; de Merlo, Gaspar González

    2013-01-01

    Background & objectives: The major cause of fertilisation failure after ICSI is failure of the oocyte to initiate the biochemical processes necessary for activation. This inability could be ascribed to cytoplasmic immaturity of those gametes even if they had reached nuclear maturity. The activation of a mature oocyte is characterised by release from metaphase II (MII) arrest and extrusion of the second polar body, followed by pro-nuclear formation. The aim of this study was to evaluate the fate of in vitro matured (IVM) metaphase I (MI) oocytes subjected to intracytoplasmic sperm injection (ICSI) at different time intervals after extrusion of the first polar body (1PB) in in vitro fertilization (IVF) cycles. Methods: A total of 8030 oocytes were collected from 1400 ICSI cycles, 5504 MII at the time of cumulus retrieval. Four hundred eight metaphase II (MII) (27.1%) matured to MII after in vitro culture for 2-26 h and 5389 sibling MII in the moment of oocyte denudation were injected. On the other hand, 49 ICSI cycles containing only MI oocytes at retrieval were injected at three different time intervals after reaching the MII. The intervals were as follows: 2-6 h (n=10), 8-11 h (n=4) and 23-26 h (n=10). Fertilization and development potential were evaluated in both studies. Results: Fertilization, embryo cleavage and quality were significantly lower in IVM MI compared to MII at time of denudation. Pregnancy rate was higher in group MII. Pregnancy was achieved in three embryo transfers when ICSI was performed within 2-6 h (group I) and 8-11 h (group II) after PB extrusion. One pregnancy was obtained in group I and a healthy neonate was born. Interpretation & conclusions: Immature oocytes from women whose ovaries have been stimulated could be matured, fertilized by ICSI, cleaved in vitro and to give rise to a live birth. However, the developmental competence of embryos derived from immature oocytes is reduced, compared with sibling in vivo matured oocytes. Further

  10. Rheotaxis guides mammalian sperm

    PubMed Central

    Miki, Kiyoshi; Clapham, David E

    2013-01-01

    Background In sea urchins, spermatozoan motility is altered by chemotactic peptides, giving rise to the assumption that mammalian eggs also emit chemotactic agents that guide spermatozoa through the female reproductive tract to the mature oocyte. Mammalian spermatozoa indeed undergo complex adaptations within the female (the process of capacitation) that are initiated by agents ranging from pH to progesterone, but these factors are not necessarily taxic. Currently, chemotaxis, thermotaxis, and rheotaxis have not been definitively established in mammals. Results Here, we show that positive rheotaxis, the ability of organisms to orient and swim against the flow of surrounding fluid, is a major taxic factor for mouse and human sperm. This flow is generated within 4 hours of sexual stimulation and coitus in female mice; prolactin-triggered oviductal fluid secretion clears the oviduct of debris, lowers viscosity, and generates the stream that guides sperm migration in the oviduct. Rheotaxic movement is demonstrated in capacitated and uncapacitated spermatozoa in low and high viscosity medium. Finally, we show that a unique sperm motion we quantify using the sperm head's rolling rate reflects sperm rotation that generates essential force for positioning the sperm in the stream. Rotation requires CatSper channels, presumably by enabling Ca2+ influx. Conclusions We propose that rheotaxis is a major determinant of sperm guidance over long distances in the mammalian female reproductive tract. Coitus induces fluid flow to guide sperm in the oviduct. Sperm rheotaxis requires rotational motion during CatSper channel-dependent hyperactivated motility. PMID:23453951

  11. Comparisons of Sperm Storage Tubule Distribution and Number in Four Strains of Mature Broiler Breeders and in Turkey Hens Before and After the Onset of Photostimulation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The biological basis of sustained fertility in broiler and turkey hens is their capacity to store sperm in the oviductal sperm storage tubules (SSTs) located in the uterovaginal junction. The objectives of this study were to determine if the numbers of SST varied between four strains of broiler bre...

  12. Effect of medium variations (zinc supplementation during oocyte maturation, perifertilization pH, and embryo culture protein source) on equine embryo development after intracytoplasmic sperm injection.

    PubMed

    Choi, Young-Ho; Gibbons, John R; Canesin, Heloísa S; Hinrichs, Katrin

    2016-10-15

    Prospective studies were conducted to help define procedural factors affecting in vitro embryo production via intracytoplasmic sperm injection (ICSI) of equine oocytes. In experiment 1, use of 10% fetal bovine serum as a protein source in embryo culture medium resulted in a higher blastocyst rate than did use of a combination of 3% fetal bovine serum, 3% equine preovulatory follicular fluid, and 4% human serum substitute (37% vs. 15%, respectively, P < 0.05). In experiment 2, the effect of zinc supplementation (0, 0.5, 1, or 1.5 μg/mL) during IVM was examined. There were no significant differences in rates of cleavage or blastocyst development (20%-31%). However, the proportion of blastocysts that developed on Day 7 for the added-zinc treatments was significantly higher than that for the control treatment (45% vs. 8%). In experiment 3, we tested whether use of high-pH medium (pH 8.0-8.4) during ICSI procedures would improve blastocyst rate when sperm with low cleavage rates after ICSI was used. When high-pH conditions were used for sperm preparation and also for the first 2 hours of incubation of injected oocytes after ICSI, the cleavage rate was unaffected but no blastocysts developed (0% vs. 24% for control). When high-pH conditions were used for sperm preparation only, the blastocyst rate was 37%. This was repeated using sperm from a second stallion; there was no significant difference in cleavage or blastocyst rates between sperm preparation in high pH vs. control medium. These findings add to our knowledge of factors affecting in vitro production of equine embryos.

  13. Types, Causes, Detection and Repair of DNA Fragmentation in Animal and Human Sperm Cells

    PubMed Central

    González-Marín, Clara; Gosálvez, Jaime; Roy, Rosa

    2012-01-01

    Concentration, motility and morphology are parameters commonly used to determine the fertilization potential of an ejaculate. These parameters give a general view on the quality of sperm but do not provide information about one of the most important components of the reproductive outcome: DNA. Either single or double DNA strand breaks can set the difference between fertile and infertile males. Sperm DNA fragmentation can be caused by intrinsic factors like abortive apoptosis, deficiencies in recombination, protamine imbalances or oxidative stress. Damage can also occur due to extrinsic factors such as storage temperatures, extenders, handling conditions, time after ejaculation, infections and reaction to medicines or post-testicular oxidative stress, among others. Two singular characteristics differentiate sperm from somatic cells: Protamination and absence of DNA repair. DNA repair in sperm is terminated as transcription and translation stops post-spermiogenesis, so these cells have no mechanism to repair the damage occurred during their transit through the epididymis and post-ejaculation. Oocytes and early embryos have been shown to repair sperm DNA damage, so the effect of sperm DNA fragmentation depends on the combined effects of sperm chromatin damage and the capacity of the oocyte to repair it. In this contribution we review some of these issues. PMID:23203048

  14. Feline spermatozoa from fresh and cryopreserved testicular tissues have comparable ability to fertilize matured oocytes and sustain the embryo development after intracytoplasmic sperm injection.

    PubMed

    Buarpung, S; Tharasanit, T; Comizzoli, P; Techakumphu, M

    2013-01-01

    Cryopreservation of testicular tissue associated with intracytoplasmic sperm injection (ICSI) is a critical tool that still needs to be explored for preserving the fertility of endangered species. Using the domestic cat as a model for wild felids, the study aimed at determining the effect of different cryoprotectants and freezing techniques (two-step freezing vs. controlled slow freezing) on the sperm quality (membrane and DNA integrity). Then, spermatozoa were extracted from frozen-thawed testicular tissues and used for ICSI to assess early gamete activation or developmental competence in vitro. The percentage of spermatozoa with intact plasma membrane was not different (P > 0.05) among nonfrozen control, glycerol-, and ethylene glycol-frozen tissues (63.2 ± 2%, 58.2 ± 2.6%, 53.3 ± 2.3%, respectively). However, these percentages were significantly lower (P < 0.05) in groups of dimethyl sulfoxide (46.3 ± 3.3%) and 1,2 propanediol (44.3 ± 2.9%) when compared with control. Conventional freezing combined with 5% (vol/vol) glycerol best preserved sperm membrane integrity (55.0 ± 2.7%) when compared with other freezing techniques. The incidence of DNA fragmentation was found to be low (0.2%-1.1%) in all freezing protocols. After ICSI with frozen testicular spermatozoa, male and female gametes were asynchronously activated and the percentages of normal fertilization at 6, 12, and 18 hours were 11.2%, 20.6%, and 22.1%, respectively. Metaphase II-arrested oocytes containing or not a decondensed sperm head were predominantly found after ICSI with frozen testicular spermatozoa. Although two-pronucleus formation could be observed as soon as 6 hours post ICSI (10%), the rate increased dramatically after 12 and 18 hours post ICSI (17.2% and 19.5%, respectively). ICSI using frozen-thawed testicular spermatozoa yielded cleavage (32.7%), morula (6.5%), and blastocyst (4.4%) percentages similar to nonfrozen control (P > 0.05). It is concluded that conventional freezing

  15. Effect of recombinant human follicle-stimulating hormone and luteinizing hormone on in vitro maturation of porcine oocytes evaluated by the subsequent in vitro development of embryos obtained by in vitro fertilization, intracytoplasmic sperm injection, or parthenogenetic activation.

    PubMed

    Silvestre, M A; Alfonso, J; García-Mengual, E; Salvador, I; Duque, C C; Molina, I

    2007-05-01

    The aim of this work was to study the effect of recombinant human (rh) FSH and LH on in vitro maturation of pig oocytes compared with a conventional hormonal supplement based on equine (PMSG) and human chorionic gonadotropins (hCG), as evaluated by the developmental ability of 3 types of pig embryos obtained by in vitro fertilization (IVF), intracytoplasmic sperm injection (ICSI), or artificial activation (ATA). In Exp. 1, one cumulus-oocyte complex group (A group) was supplemented with rh-FSH and rh-LH (0.1 IU/mL each), and the other group (B group) was supplemented with PMSG and hCG (10 IU/mL each). No differences in nuclear maturation between the A and B groups were observed (68.5 vs. 71.4%, respectively). No differences were detected between hormonal treatments in the rates of cleavage or blastocyst formation of ATA, IVF, and ICSI embryos. Total cell number of the embryos was not significantly different in any experimental group (A: 31.1, 28.5, and 19.8 vs. B: 25.2, 25.5, and 20.6 for ATA, IVF, and ICSI embryos, respectively). In Exp. 2, the effects of different concentrations of rh-FSH and rh-LH (0.5, 0.1, or 0.05 IU/mL) in maturation medium on nuclear maturation and in vitro development of embryos obtained by IVF were studied. No effect of different hormonal concentrations on blastocyst formation rates was observed (8.5, 13.0, and 5.7%, respectively). Blastocyst cell number was not different in any experimental group. In conclusion, the results obtained here permit us to substitute PMSG and hCG with rh-FSH and rh-LH and to produce pig embryos obtained by IVF, ICSI, or ATA.

  16. Sugar-coated sperm: Unraveling the functions of the mammalian sperm glycocalyx.

    PubMed

    Tecle, Eillen; Gagneux, Pascal

    2015-09-01

    Mammalian spermatozoa are coated with a thick glycocalyx that is assembled during sperm development, maturation, and upon contact with seminal fluid. The sperm glycocalyx is critical for sperm survival in the female reproductive tract and is modified during capacitation. The complex interplay among the various glycoconjugates generates numerous signaling motifs that may regulate sperm function and, as a result, fertility. Nascent spermatozoa assemble their own glycans while the cells still possess a functional endoplasmic reticulum and Golgi in the seminiferous tubule, but once spermatogenesis is complete, they lose the capacity to produce glycoconjugates de novo. Sperm glycans continue to be modified, during epididymal transit by extracellular glycosidases and glycosyltransferases. Furthermore, epididymal cells secrete glycoconjugates (glycophosphatidylinositol-anchored glycoproteins and glycolipids) and glycan-rich microvesicles that can fuse with the maturing sperm membrane. The sperm glycocalyx mediates numerous functions in the female reproductive tract, including the following: inhibition of premature capacitation; passage through the cervical mucus; protection from innate and adaptive female immunity; formation of the sperm reservoir; and masking sperm proteins involved in fertilization. The immense diversity in sperm-associated glycans within and between species forms a remarkable challenge to our understanding of essential sperm glycan functions.

  17. Intracellular pH in sperm physiology.

    PubMed

    Nishigaki, Takuya; José, Omar; González-Cota, Ana Laura; Romero, Francisco; Treviño, Claudia L; Darszon, Alberto

    2014-08-01

    Intracellular pH (pHi) regulation is essential for cell function. Notably, several unique sperm ion transporters and enzymes whose elimination causes infertility are either pHi dependent or somehow related to pHi regulation. Amongst them are: CatSper, a Ca(2+) channel; Slo3, a K(+) channel; the sperm-specific Na(+)/H(+) exchanger and the soluble adenylyl cyclase. It is thus clear that pHi regulation is of the utmost importance for sperm physiology. This review briefly summarizes the key components involved in pHi regulation, their characteristics and participation in fundamental sperm functions such as motility, maturation and the acrosome reaction.

  18. A novel SoxB2 gene is required for maturation of sperm nucleus during spermiogenesis in the Chinese mitten crab, Eriocheir sinensis

    PubMed Central

    Liu, Zhi-Qiang; Jiang, Xue-Hui; Qi, Hai-Yan; Xiong, Liang-Wei; Qiu, Gao-Feng

    2016-01-01

    SRY-related HMG box (Sox) genes are characterized by the presence of a DNA-binding HMG domain and involved in a diverse range of developmental processes. In this study, we identified a novel Sox gene, designated as EsSoxB2-1, from the Chinese mitten crab Eriocheir sinensis. The EsSoxB2-1 encodes a protein of 259 amino acids, sharing the highest identity with the beetle Tribolium castaneum SOX21b. Unlike insect Sox21b, however, EsSoxB2-1 is intronless and exhibits a gonad-specific expression pattern at both mRNA and protein level. Two core promoters in 5′ flanking region were demonstrated to be essential for inducing transcriptional regulatory activity. The transcription of EsSoxB2-1 mRNA begins in spermatogonia stage, while the translation of EsSOXB2-1 protein initiates at spermiogenesis stage. Interestingly, EsSOXB2-1 protein was exclusively localized in the nucleus of spermatid and spermatozoa even at the end of acrosome reaction, and was bound to the uncondensed chromatin in nucleoplasm of mature spermatozoa. Knockdown of EsSoxB2-1 by RNAi leads to abnormal transformation of the nucleus during spermiogenesis. Together, these findings demonstrated the requirement of EsSoxB2-1 for the spermatozoa nucleus maturation and also suggested that EsSoxB2-1 would be delivered into fertilized eggs along with chromatins as a paternal transcription factor for regulating early embryonic development. PMID:27561408

  19. A novel SoxB2 gene is required for maturation of sperm nucleus during spermiogenesis in the Chinese mitten crab, Eriocheir sinensis.

    PubMed

    Liu, Zhi-Qiang; Jiang, Xue-Hui; Qi, Hai-Yan; Xiong, Liang-Wei; Qiu, Gao-Feng

    2016-01-01

    SRY-related HMG box (Sox) genes are characterized by the presence of a DNA-binding HMG domain and involved in a diverse range of developmental processes. In this study, we identified a novel Sox gene, designated as EsSoxB2-1, from the Chinese mitten crab Eriocheir sinensis. The EsSoxB2-1 encodes a protein of 259 amino acids, sharing the highest identity with the beetle Tribolium castaneum SOX21b. Unlike insect Sox21b, however, EsSoxB2-1 is intronless and exhibits a gonad-specific expression pattern at both mRNA and protein level. Two core promoters in 5' flanking region were demonstrated to be essential for inducing transcriptional regulatory activity. The transcription of EsSoxB2-1 mRNA begins in spermatogonia stage, while the translation of EsSOXB2-1 protein initiates at spermiogenesis stage. Interestingly, EsSOXB2-1 protein was exclusively localized in the nucleus of spermatid and spermatozoa even at the end of acrosome reaction, and was bound to the uncondensed chromatin in nucleoplasm of mature spermatozoa. Knockdown of EsSoxB2-1 by RNAi leads to abnormal transformation of the nucleus during spermiogenesis. Together, these findings demonstrated the requirement of EsSoxB2-1 for the spermatozoa nucleus maturation and also suggested that EsSoxB2-1 would be delivered into fertilized eggs along with chromatins as a paternal transcription factor for regulating early embryonic development. PMID:27561408

  20. Sperm competition leads to functional adaptations in avian testes to maximize sperm quantity and quality.

    PubMed

    Lüpold, Stefan; Wistuba, Joachim; Damm, Oliver S; Rivers, James W; Birkhead, Tim R

    2011-05-01

    The outcome of sperm competition (i.e. competition for fertilization between ejaculates from different males) is primarily determined by the relative number and quality of rival sperm. Therefore, the testes are under strong selection to maximize both sperm number and quality, which are likely to result in trade-offs in the process of spermatogenesis (e.g. between the rate of spermatogenesis and sperm length or sperm energetics). Comparative studies have shown positive associations between the level of sperm competition and both relative testis size and the proportion of seminiferous (sperm-producing) tissue within the testes. However, it is unknown how the seminiferous tissue itself or the process of spermatogenesis might evolve in response to sperm competition. Therefore, we quantified the different germ cell types and Sertoli cells (SC) in testes to assess the efficiency of sperm production and its associations with sperm length and mating system across 10 species of New World Blackbirds (Icteridae) that show marked variation in sperm length and sperm competition level. We found that species under strong sperm competition generate more round spermatids (RS)/spermatogonium and have SC that support a greater number of germ cells, both of which are likely to increase the maximum sperm output. However, fewer of the RS appeared to elongate to mature spermatozoa in these species, which might be the result of selection for discarding spermatids with undesirable characteristics as they develop. Our results suggest that, in addition to overall size and gross morphology, testes have also evolved functional adaptations to maximize sperm quantity and quality. PMID:21307271

  1. The Rhesus macaque (Macaca mulatta) sperm proteome.

    PubMed

    Skerget, Sheri; Rosenow, Matthew; Polpitiya, Ashoka; Petritis, Konstantinos; Dorus, Steve; Karr, Timothy L

    2013-11-01

    Mass spectrometry based proteomics has facilitated sperm composition studies in several mammalian species but no studies have been undertaken in non-human primate species. Here we report the analysis of the 1247 proteins that comprise the Rhesus macaque (Macaca mulatta) sperm proteome (termed the MacSP). Comparative analysis with previously characterized mouse and human sperm proteomes reveals substantial levels of orthology (47% and 40% respectively) and widespread overlap of functional categories based on Gene Ontology analyses. Approximately 10% of macaque sperm genes (113/1247) are significantly under-expressed in the testis as compared with other tissues, which may reflect proteins specifically acquired during epididymal maturation. Phylogenetic and genomic analyses of three MacSP ADAMs (A-Disintegrin and Metalloprotease proteins), ADAM18-, 20- and 21-like, provides empirical support for sperm genes functioning in non-human primate taxa which have been subsequently lost in the lineages leading to humans. The MacSP contains proteasome proteins of the 20S core subunit, the 19S proteasome activator complex and an alternate proteasome activator PA200, raising the possibility that proteasome activity is present in mature sperm. Robust empirical characterization of the Rhesus sperm proteome should greatly expand the possibility for targeted molecular studies of spermatogenesis and fertilization in a commonly used model species for human infertility.

  2. The Rhesus Macaque (Macaca mulatta) Sperm Proteome*

    PubMed Central

    Skerget, Sheri; Rosenow, Matthew; Polpitiya, Ashoka; Petritis, Konstantinos; Dorus, Steve; Karr, Timothy L.

    2013-01-01

    Mass spectrometry based proteomics has facilitated sperm composition studies in several mammalian species but no studies have been undertaken in non-human primate species. Here we report the analysis of the 1247 proteins that comprise the Rhesus macaque (Macaca mulatta) sperm proteome (termed the MacSP). Comparative analysis with previously characterized mouse and human sperm proteomes reveals substantial levels of orthology (47% and 40% respectively) and widespread overlap of functional categories based on Gene Ontology analyses. Approximately 10% of macaque sperm genes (113/1247) are significantly under-expressed in the testis as compared with other tissues, which may reflect proteins specifically acquired during epididymal maturation. Phylogenetic and genomic analyses of three MacSP ADAMs (A-Disintegrin and Metalloprotease proteins), ADAM18-, 20- and 21-like, provides empirical support for sperm genes functioning in non-human primate taxa which have been subsequently lost in the lineages leading to humans. The MacSP contains proteasome proteins of the 20S core subunit, the 19S proteasome activator complex and an alternate proteasome activator PA200, raising the possibility that proteasome activity is present in mature sperm. Robust empirical characterization of the Rhesus sperm proteome should greatly expand the possibility for targeted molecular studies of spermatogenesis and fertilization in a commonly used model species for human infertility. PMID:23816990

  3. Use of Fluorescent Dyes for Readily Recognizing Sperm Damage

    PubMed Central

    Farah, Omar Ibrahim; Cuiling, Li; Jiaojiao, Wang; Huiping, Zhang

    2013-01-01

    Sperm is produced by the testis and mature in the epididymis. For having a successful conception, the fertilizing sperm should have functional competent membranes, intact acrosome, functional mitochondria and an intact haploid genome. The effects of genetic and environmental factors result in sperm vulnerability to damage in the process of spermatogenesis and maturation. In recent years, the feasibility of detecting sperm damage is enhanced through the advances in technologies like fluoscerent staining techniques assisted with fluorescence microscope, flow cytometry and computer analysis systems. Fluoscerent staining techniques involve the use of fluorescent dyes, either directly or indirectly for binding them with some ingredients of sperm and evaluating the damage of the structure or function of the sperm, i.e. membrane, acrosome, mitochondria, chromosome or DNA. PMID:24163795

  4. A comparison of ejaculated and testicular spermatozoa aneuploidy rates in patients with high sperm DNA damage.

    PubMed

    Moskovtsev, Sergey I; Alladin, Naazish; Lo, Kirk C; Jarvi, Keith; Mullen, J Brendan M; Librach, Clifford L

    2012-06-01

    Testicular spermatozoa are utilized to achieve pregnancy in couples with severe male factor infertility. Several studies suggest that aneuploidy rates in spermatozoa are elevated at the testicular level in infertile patients compared to ejaculates of normal controls. However, essential data regarding aneuploidy rates between ejaculated and testicular spermatozoa in the same individuals is lacking. The purpose of our study was to compare aneuploidy rates at the testicular and post-testicular level from the same patients with persistently high sperm DNA damage. Ejaculates and testicular biopsies were obtained from eight patients with persistently high DNA damage (>30%). Both ejaculated and testicular samples were analyzed for sperm DNA damage and sperm aneuploidy for chromosomes 13, 18, 21, X, and Y. In addition, semen samples from ten normozoospermic men presenting for fertility evaluation served as a control group. A strong correlation between the alteration of spermatogenesis and chromatin deterioration was observed in our study. In the same individuals, testicular samples showed a significantly lower DNA damage compared to ejaculated spermatozoa (14.9% ± 5.0 vs. 40.6% ± 14.8, P<0.05), but significantly higher aneuploidy rates for the five analyzed chromosomes (12.41% ± 3.7 vs. 5.77% ± 1.2, P<0.05). While testicular spermatozoa appear favourable for ICSI in terms of lower DNA damage, this potential advantage could be offset by the higher aneuploidy rates in testicular spermatozoa.

  5. Left-handed sperm removal by male Calopteryx damselflies (Odonata).

    PubMed

    Tsuchiya, Kaori; Hayashi, Fumio

    2014-01-01

    Male genitalia in several insect species are asymmetry in right and left shape. However, the function of such asymmetric male genitalia is still unclear. We found that the male genitalia of the damselfly Calopteryx cornelia (Odonata: Calopterygidae) are morphologically symmetric just after emergence but asymmetric after reproductive maturation. Males remove rival sperm stored in the female bursa copulatrix (single spherical sac) and the following spermatheca (Y-shaped tubular sac) prior to their own ejaculation to prevent sperm competition. Males possess the aedeagus with a recurved head to remove bursal sperm and a pair of spiny lateral processes to remove spermathecal sperm. The right lateral process is less developed than the left, and sperm stored in the right spermathecal tube are rarely removed. Experiments involving surgical cutting of each lateral process demonstrated that only the left process functions in spermathecal sperm removal. Thus, males of C. cornelia are left-handed in their sperm removal behaviour at copulation.

  6. Sperm viability - Determination of sperm viability using fluorescence microscopy

    Technology Transfer Automated Retrieval System (TEKTRAN)

    To determine the percentage of viable sperm in a semen sample using stains that differentiates viable (live) sperm from nonviable (dead) sperm. Viable sperm are detected by SYBR-14, which stains the sperm nuclei green. Nonviable sperm are detected by propidium iodide (PI), which stains the sperm red...

  7. Characterisation of the Manduca sexta sperm proteome: Genetic novelty underlying sperm composition in Lepidoptera.

    PubMed

    Whittington, Emma; Zhao, Qian; Borziak, Kirill; Walters, James R; Dorus, Steve

    2015-07-01

    The application of mass spectrometry based proteomics to sperm biology has greatly accelerated progress in understanding the molecular composition and function of spermatozoa. To date, these approaches have been largely restricted to model organisms, all of which produce a single sperm morph capable of oocyte fertilisation. Here we apply high-throughput mass spectrometry proteomic analysis to characterise sperm composition in Manduca sexta, the tobacco hornworm moth, which produce heteromorphic sperm, including one fertilisation competent (eupyrene) and one incompetent (apyrene) sperm type. This resulted in the high confidence identification of 896 proteins from a co-mixed sample of both sperm types, of which 167 are encoded by genes with strict one-to-one orthology in Drosophila melanogaster. Importantly, over half (55.1%) of these orthologous proteins have previously been identified in the D. melanogaster sperm proteome and exhibit significant conservation in quantitative protein abundance in sperm between the two species. Despite the complex nature of gene expression across spermatogenic stages, a significant correlation was also observed between sperm protein abundance and testis gene expression. Lepidopteran-specific sperm proteins (e.g., proteins with no homology to proteins in non-Lepidopteran taxa) were present in significantly greater abundance on average than those with homology outside the Lepidoptera. Given the disproportionate production of apyrene sperm (96% of all mature sperm in Manduca) relative to eupyrene sperm, these evolutionarily novel and highly abundant proteins are candidates for possessing apyrene-specific functions. Lastly, comparative genomic analyses of testis-expressed, ovary-expressed and sperm genes identified a concentration of novel sperm proteins shared amongst Lepidoptera of potential relevance to the evolutionary origin of heteromorphic spermatogenesis. As the first published Lepidopteran sperm proteome, this whole

  8. Computer assisted sperm morphometry in mammals: a review.

    PubMed

    Yániz, J L; Soler, C; Santolaria, P

    2015-05-01

    Computer-assisted sperm morphometry analysis (CASMA or ASMA) systems were developed to reduce the subjectivity of sperm morphology assessement. This review focuses on a complete description of the CASMA technique, including recent developments, factors of variation, results in the different species and possible applications. Techniques to study sperm morphometry include light microscopy, phase-contrast microscopy and, more recently, fluorescence microscopy. Most published studies on sperm morphometry have been centered on the whole sperm heads, although some of them also measured other parts of the sperm structure, such as the nucleus, acrosome, midpiece or flagellum. The independent study of sperm components may be more informative than the traditional assessment of the whole sperm head. Morphometric data provided by the CASMA system may be analyzed using classical statistics although, given the heterogeneity of spermatozoa in the ejaculates, the study of sperm subpopulations using clustering procedures may be more informative. Morphometric results may vary depending on factors intrinsic and extrinsic to the semen donor. Intrinsic factors may include, among others, genetic factors, age and sexual maturity. Extrinsic factors may include those related to the influence of environment on the donor, as well as those related with sample processing and the morphometric analysis itself. Once standardized, this technique may provide relevant information in studies focused on evolutionary biology, sperm formation, sperm quality assessment, including prediction of the potential fertility, semen cryopreservation, or the effect of reprotoxicants. PMID:25802026

  9. Etiologies of sperm oxidative stress

    PubMed Central

    Sabeti, Parvin; Pourmasumi, Soheila; Rahiminia, Tahereh; Akyash, Fatemeh; Talebi, Ali Reza

    2016-01-01

    Sperm is particularly susceptible to reactive oxygen species (ROS) during critical phases of spermiogenesis. However, the level of seminal ROS is restricted by seminal antioxidants which have beneficial effects on sperm parameters and developmental potentials. Mitochondria and sperm plasma membrane are two major sites of ROS generation in sperm cells. Besides, leukocytes including polymer phonuclear (PMN) leukocytes and macrophages produce broad category of molecules including oxygen free radicals, non-radical species and reactive nitrogen species. Physiological role of ROS increase the intracellular cAMP which then activate protein kinase in male reproductive system. This indicates that spermatozoa need small amounts of ROS to acquire the ability of nuclear maturation regulation and condensation to fertilize the oocyte. There is a long list of intrinsic and extrinsic factors which can induce oxidative stress to interact with lipids, proteins and DNA molecules. As a result, we have lipid peroxidation, DNA fragmentation, axonemal damage, denaturation of the enzymes, over generation of superoxide in the mitochondria, lower antioxidant activity and finally abnormal spermatogenesis. If oxidative stress is considered as one of the main cause of DNA damage in the germ cells, then there should be good reason for antioxidant therapy in these conditions. PMID:27351024

  10. Etiologies of sperm oxidative stress.

    PubMed

    Sabeti, Parvin; Pourmasumi, Soheila; Rahiminia, Tahereh; Akyash, Fatemeh; Talebi, Ali Reza

    2016-04-01

    Sperm is particularly susceptible to reactive oxygen species (ROS) during critical phases of spermiogenesis. However, the level of seminal ROS is restricted by seminal antioxidants which have beneficial effects on sperm parameters and developmental potentials. Mitochondria and sperm plasma membrane are two major sites of ROS generation in sperm cells. Besides, leukocytes including polymer phonuclear (PMN) leukocytes and macrophages produce broad category of molecules including oxygen free radicals, non-radical species and reactive nitrogen species. Physiological role of ROS increase the intracellular cAMP which then activate protein kinase in male reproductive system. This indicates that spermatozoa need small amounts of ROS to acquire the ability of nuclear maturation regulation and condensation to fertilize the oocyte. There is a long list of intrinsic and extrinsic factors which can induce oxidative stress to interact with lipids, proteins and DNA molecules. As a result, we have lipid peroxidation, DNA fragmentation, axonemal damage, denaturation of the enzymes, over generation of superoxide in the mitochondria, lower antioxidant activity and finally abnormal spermatogenesis. If oxidative stress is considered as one of the main cause of DNA damage in the germ cells, then there should be good reason for antioxidant therapy in these conditions. PMID:27351024

  11. Intracellular pH in sperm physiology.

    PubMed

    Nishigaki, Takuya; José, Omar; González-Cota, Ana Laura; Romero, Francisco; Treviño, Claudia L; Darszon, Alberto

    2014-08-01

    Intracellular pH (pHi) regulation is essential for cell function. Notably, several unique sperm ion transporters and enzymes whose elimination causes infertility are either pHi dependent or somehow related to pHi regulation. Amongst them are: CatSper, a Ca(2+) channel; Slo3, a K(+) channel; the sperm-specific Na(+)/H(+) exchanger and the soluble adenylyl cyclase. It is thus clear that pHi regulation is of the utmost importance for sperm physiology. This review briefly summarizes the key components involved in pHi regulation, their characteristics and participation in fundamental sperm functions such as motility, maturation and the acrosome reaction. PMID:24887564

  12. Intracellular pH in Sperm Physiology

    PubMed Central

    Nishigaki, Takuya; José, Omar; González-Cota, Ana Laura; Romero, Francisco; Treviño, Claudia L.; Darszon, Alberto

    2014-01-01

    Intracellular pH (pHi) regulation is essential for cell function. Notably, several unique sperm ion transporters and enzymes whose elimination causes infertility are either pHi dependent or somehow related to pHi regulation. Amongst them are: CatSper, a Ca2+ channel; Slo3, a K+ channel; the sperm-specific Na+/H+ exchanger and the soluble adenylyl cyclase. It is thus clear that pHi regulation is of the utmost importance for sperm physiology. This review briefly summarizes the key components involved in pHi regulation, their characteristics and participation in fundamental sperm functions such as motility, maturation and the acrosome reaction. PMID:24887564

  13. Sperm phosphoproteomics: historical perspectives and current methodologies

    PubMed Central

    Porambo, James R; Salicioni, Ana M; Visconti, Pablo E; Platt, Mark D

    2013-01-01

    Mammalian sperm are differentiated germ cells that transfer genetic material from the male to the female. Owing to this essential role in the reproductive process, an understanding of the complex mechanisms that underlie sperm function has implications ranging from the development of novel contraceptives to the treatment of male infertility. While the importance of phosphorylation in sperm differentiation, maturation and fertilization has been well established, the ability to directly determine the sites of phosphorylation within sperm proteins and to quantitate the extent of phosphorylation at these sites is a recent development that has relied almost exclusively on advances in the field of proteomics. This review will summarize the work that has been carried out to date on sperm phosphoproteomics and discuss how the resulting qualitative and quantitative information has been used to provide insight into the manner in which protein phosphorylation events modulate sperm function. The authors also present the proteomics process as it is most often utilized for the elucidation of protein expression, with a particular emphasis on the way in which the process has been modified for the analysis of protein phosphorylation in sperm. PMID:23194270

  14. Sperm nuclear proteome and its epigenetic potential.

    PubMed

    Castillo, J; Amaral, A; Oliva, R

    2014-05-01

    The main function of the sperm cell is to transmit the paternal genetic message and epigenetic information to the embryo. Importantly, the majority of the genes in the sperm chromatin are highly condensed by protamines, whereas genes potentially needed in the initial stages of development are associated with histones, representing a form of epigenetic marking. However, so far little attention has been devoted to other sperm chromatin-associated proteins that, in addition to histones and protamines, may also have an epigenetic role. Therefore, with the goal of contributing to cover this subject we have compiled, reviewed and report a list of 581 chromatin or nuclear proteins described in the human sperm cell. Furthermore, we have analysed their Gene Ontology Biological Process enriched terms and have grouped them into different functional categories. Remarkably, we show that 56% of the sperm nuclear proteins have a potential epigenetic activity, being involved in at least one of the following functions: chromosome organization, chromatin organization, protein-DNA complex assembly, DNA packaging, gene expression, transcription, chromatin modification and histone modification. In addition, we have also included and compared the sperm cell proteomes of different model species, demonstrating the existence of common trends in the chromatin composition in the mammalian mature male gamete. Taken together, our analyses suggest that the mammalian sperm cell delivers to the offspring a rich combination of histone variants, transcription factors, chromatin-associated and chromatin-modifying proteins which have the potential to encode and transmit an extremely complex epigenetic information. PMID:24327354

  15. Management and Breeding Soundness of Mature Bulls.

    PubMed

    Palmer, Colin W

    2016-07-01

    Mature bulls must be fed a balanced ration, vaccinated appropriately, and undergo a breeding soundness evaluation to ensure they meet what is required of a short, but intense breeding season. To be classified as a satisfactory potential breeder, minimum standards for physical soundness, scrotal circumference, sperm motility, and sperm morphology must be achieved using an accepted bull-breeding soundness evaluation format. Sperm production requires approximately 70 days. Heat and stress are the most common insults to spermatogenesis, causing an increase in morphologic abnormalities with obesity-associated scrotal fat accumulation being the most frequent cause of elevated testicular temperature in mature bulls.

  16. Comparative Transcriptomics of Arabidopsis thaliana Sperm Cells

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In flowering plants the two sperm cells are embedded within the cytoplasm of the growing pollen tube and as such are passively transported to the embryo sac, wherein double fertilization occurs upon their release. Understanding the mechanisms and conditions by which male gametes mature and take part...

  17. Sperm head phenotype and male fertility in ram semen.

    PubMed

    Maroto-Morales, A; Ramón, M; García-Álvarez, O; Montoro, V; Soler, A J; Fernández-Santos, M R; Roldan, E R S; Pérez-Guzmán, M D; Garde, J J

    2015-12-01

    Although there is ample evidence for the effects of sperm head shape on sperm function, its impact on fertility has not been explored in detail at the intraspecific level in mammals. Here, we assess the relationship between sperm head shape and male fertility in a large-scale study in Manchega sheep (Ovis aries), which have not undergone any selection for fertility. Semen was collected from 83 mature rams, and before insemination, head shapes were measured for five parameters: area, perimeter, length, width, and p2a (perimeter(2)/2×π×area) using a computer-assisted sperm morphometric analysis. In addition, a cluster analysis using sperm head length and p2a factor was performed to determine sperm subpopulations (SPs) structure. Our results show the existence of four sperm SPs, which present different sperm head phenotype: SP1 (large and round), SP2 (short and elongated), SP3 (shortest and round), and SP4 (large and the most elongated). No relationships were found between males' fertility rates and average values of sperm head dimensions. However, differences in fertility rates between rams were strongly associated to the proportion of spermatozoa in an ejaculate SP with short and elongated heads (P < 0.001). These findings show how the heterogeneity in sperm head shape of the ejaculate has an effect on reproductive success, and highlight the important role of modulation of the ejaculate at the intraspecific level.

  18. Sperm head phenotype and male fertility in ram semen.

    PubMed

    Maroto-Morales, A; Ramón, M; García-Álvarez, O; Montoro, V; Soler, A J; Fernández-Santos, M R; Roldan, E R S; Pérez-Guzmán, M D; Garde, J J

    2015-12-01

    Although there is ample evidence for the effects of sperm head shape on sperm function, its impact on fertility has not been explored in detail at the intraspecific level in mammals. Here, we assess the relationship between sperm head shape and male fertility in a large-scale study in Manchega sheep (Ovis aries), which have not undergone any selection for fertility. Semen was collected from 83 mature rams, and before insemination, head shapes were measured for five parameters: area, perimeter, length, width, and p2a (perimeter(2)/2×π×area) using a computer-assisted sperm morphometric analysis. In addition, a cluster analysis using sperm head length and p2a factor was performed to determine sperm subpopulations (SPs) structure. Our results show the existence of four sperm SPs, which present different sperm head phenotype: SP1 (large and round), SP2 (short and elongated), SP3 (shortest and round), and SP4 (large and the most elongated). No relationships were found between males' fertility rates and average values of sperm head dimensions. However, differences in fertility rates between rams were strongly associated to the proportion of spermatozoa in an ejaculate SP with short and elongated heads (P < 0.001). These findings show how the heterogeneity in sperm head shape of the ejaculate has an effect on reproductive success, and highlight the important role of modulation of the ejaculate at the intraspecific level. PMID:26318229

  19. Intracytoplasmic Sperm Injection (ICSI)

    MedlinePlus

    ... male partner produces too few sperm to do artificial insemination (intrauterine insemination [IUI]) or IVF. • The sperm may ... birth defects may actually be due to the infertility and not the treatments used to overcome the ...

  20. Not all sperm are equal: functional mitochondria characterize a subpopulation of human sperm with better fertilization potential.

    PubMed

    Sousa, Ana Paula; Amaral, Alexandra; Baptista, Marta; Tavares, Renata; Caballero Campo, Pedro; Caballero Peregrín, Pedro; Freitas, Albertina; Paiva, Artur; Almeida-Santos, Teresa; Ramalho-Santos, João

    2011-03-23

    Human sperm samples are very heterogeneous and include a low amount of truly functional gametes. Distinct strategies have been developed to characterize and isolate this specific subpopulation. In this study we have used fluorescence microscopy and fluorescence-activated cell sorting to determine if mitochondrial function, as assessed using mitochondrial-sensitive probes, could be employed as a criterion to obtain more functional sperm from a given ejaculate. We first determined that mitochondrial activity correlated with the quality of distinct human samples, from healthy donors to patients with decreased semen quality. Furthermore, using fluorescence-activated cell sorting to separate sperm with active and inactive mitochondria we found that this was also true within samples. Indeed, sperm with active mitochondria defined a more functional subpopulation, which contained more capacitated and acrosome intact cells, sperm with lower chromatin damage, and, crucially, sperm more able to decondense and participate in early development using both chemical induction and injection into mature bovine oocytes. Furthermore, cell sorting using mitochondrial activity produced a more functional sperm subpopulation than classic swim-up, both in terms of improvement in a variety of functional sperm parameters and in statistical significance. In conclusion, whatever the true biological role of sperm mitochondria in fertilization, mitochondrial activity is a clear hallmark of human sperm functionality.

  1. Flow cytometry of sperm

    SciTech Connect

    Gledhill, B.L.

    1987-09-21

    This brief paper summarizes automated flow cytometric determination of sperm morphology and flow cytometry/sorting of sperm with application to sex preselection. In the latter context, mention is made of results of karyotypic determination of sex chromosome ratios in albumin-processed human sperm. 23 refs., 1 fig., 1 tab.

  2. Kinesin-1 Prevents Capture of the Oocyte Meiotic Spindle by the Sperm Aster

    PubMed Central

    McNally, Karen L.P.; Fabritius, Amy S.; Ellefson, Marina L.; Flynn, Jonathan R.; Milan, Jennifer A.; McNally, Francis J.

    2012-01-01

    Centrioles are lost during oogenesis and inherited from the sperm at fertilization. In the zygote, the centrioles recruit pericentriolar proteins from the egg to form a mature centrosome that nucleates a sperm aster. The sperm aster then captures the female pronucleus to join the maternal and paternal genomes. Because fertilization occurs before completion of female meiosis, some mechanism must prevent capture of the meiotic spindle by the sperm aster. Here we show that in wild-type Caenorhabditis elegans zygotes, maternal pericentriolar proteins are not recruited to the sperm centrioles until after completion of meiosis. Depletion of kinesin-1 heavy chain or its binding partner resulted in premature centrosome maturation during meiosis and growth of a sperm aster that could capture the oocyte meiotic spindle. Kinesin prevents recruitment of pericentriolar proteins by coating the sperm DNA and centrioles and thus prevents triploidy by a non-motor mechanism. PMID:22465668

  3. Calcium signaling and the MAPK cascade are required for sperm activation in Caenorhabditis elegans.

    PubMed

    Liu, Zhiyu; Wang, Bin; He, Ruijun; Zhao, Yanmei; Miao, Long

    2014-02-01

    In nematode, sperm activation (or spermiogenesis), a process in which the symmetric and non-motile spermatids transform into polarized and crawling spermatozoa, is critical for sperm cells to acquire fertilizing competence. SPE-8 dependent and SPE-8 independent pathways function redundantly during sperm activation in both males and hermaphrodites of Caenorhabditis elegans. However, the downstream signaling for both pathways remains unclear. Here we show that calcium signaling and the MAPK cascade are required for both SPE-8 dependent and SPE-8 independent sperm activation, implying that both pathways share common downstream signaling components during sperm activation. We demonstrate that activation of the MAPK cascade is sufficient to activate spermatids derived from either wild-type or spe-8 group mutant males and that activation of the MAPK cascade bypasses the requirement of calcium signal to induce sperm activation, indicating that the MAPK cascade functions downstream of or parallel with the calcium signaling during sperm activation. Interestingly, the persistent activation of MAPK in activated spermatozoa inhibits Major Sperm Protein (MSP)-based cytoskeleton dynamics. We demonstrate that MAPK plays dual roles in promoting pseudopod extension during sperm activation but also blocking the MSP-based, amoeboid motility of the spermatozoa. Thus, though nematode sperm are crawling cells, morphologically distinct from flagellated sperm, and the molecular machinery for motility of amoeboid and flagellated sperm is different, both types of sperm might utilize conserved signaling pathways to modulate sperm maturation.

  4. Binding of Sperm to the Zona Pellucida Mediated by Sperm Carbohydrate-Binding Proteins is not Species-Specific in Vitro between Pigs and Cattle.

    PubMed

    Takahashi, Kazuya; Kikuchi, Kazuhiro; Uchida, Yasuomi; Kanai-Kitayama, Saeko; Suzuki, Reiichiro; Sato, Reiko; Toma, Kazunori; Geshi, Masaya; Akagi, Satoshi; Nakano, Minoru; Yonezawa, Naoto

    2013-01-01

    Carbohydrates are candidates for the basis of species-selective interaction of gametes during mammalian fertilization. In this study, we sought to clarify the roles of sugar residues in the species-selective, sperm-oocyte interaction in pigs and cattle. Acrosome-intact porcine and bovine sperm exhibited their strongest binding affinities for β-Gal and α-Man residues, respectively. Porcine-sperm specificity changed from β-Gal to α-Man after the acrosome reaction, while bovine-sperm specificity did not. Binding of acrosome-intact and acrosome-reacted sperm decreased after trypsinization, indicating that the carbohydrate-binding components are proteins. While immature oocytes bound homologous sperm preferentially to heterologous sperm, oocytes matured in vitro bound similar numbers of homologous and heterologous sperm. Lectin staining revealed the aggregation of α-Man residues on the outer surface of the porcine zona during maturation. In both species, zona-free, mature oocytes bound homologous sperm preferentially to heterologous sperm. The lectin-staining patterns of the zona pellucida and zona-free oocytes coincided with the carbohydrate-binding specificities of acrosome-intact and acrosome-reacted sperm, respectively, supporting the involvement of carbohydrates in gamete recognition in pigs and cattle. These results also indicate that sperm-zona pellucida and sperm-oolemma bindings are not strictly species-specific in pigs and cattle, and further suggest that sperm penetration into the zona and/or fusion with oolemma may be species-specific between pigs and cattle.

  5. Sperm Pretreatment with Dithiothreitol Increases Male Pronucleus Formation Rates After Intracytoplasmic Sperm Injection (ICSI) in Swamp Buffalo Oocytes

    PubMed Central

    CHANKITISAKUL, Vibuntita; AM-IN, Nutthee; THARASANIT, Theerawat; SOMFAI, Tamas; NAGAI, Takashi; TECHAKUMPHU, Mongkol

    2012-01-01

    Abstract Failure of male pronucleus formation has hampered the success of intracytoplasmic sperm injection (ICSI) in swamp buffalo. The aim of the present study was to improve male pronucleus formation by pretreating sperm with various chemicals before ICSI. In Experiments1 and 2, sperm were treated according to one of the following protocols: (1) 0.1% Triton-X 100 (TX) for 1 min, (2) 10 µM calcium ionophore (CaI) for 20 min, (3) freezing and thawing (FT) without any cryoprotectant, or (4) no treatment (control). These sperm treatment groups then either did or did not receive additional sperm treatment with 5 mM dithiothreitol (DTT) for 20 min. Acrosomal integrity (Experiment 1) and DNA fragmentation (Experiment 2) were evaluated in the sperm before ICSI. In Experiment 3, oocytes matured in vitro were subjected to ICSI using pretreated sperm as described above and then were cultured either with or without activation. The TX- and CaI-treated sperm caused an increase in the number of acrosome-loss sperm, whereas the FT treatment and control increased the proportion of acrosome-reacted sperm (P<0.05). The DNA fragmentation did not differ among treatments (P>0.05). At 18 h post-ICSI, pronucleus (PN) formation was found only in activated oocytes. The majority of the activated ICSI oocytes contained intact sperm heads. Normal fertilization was observed in the CaI and FT treatment groups and control group when sperm were treated with DTT before ICSI. In conclusion, DTT treatment of sperm with reacted acrosomes before ICSI together with activation of the ICSI oocytes is important for successful male pronucleus formation. PMID:23132520

  6. Sperm is epigenetically programmed to regulate gene transcription in embryos.

    PubMed

    Teperek, Marta; Simeone, Angela; Gaggioli, Vincent; Miyamoto, Kei; Allen, George E; Erkek, Serap; Kwon, Taejoon; Marcotte, Edward M; Zegerman, Philip; Bradshaw, Charles R; Peters, Antoine H F M; Gurdon, John B; Jullien, Jerome

    2016-08-01

    For a long time, it has been assumed that the only role of sperm at fertilization is to introduce the male genome into the egg. Recently, ideas have emerged that the epigenetic state of the sperm nucleus could influence transcription in the embryo. However, conflicting reports have challenged the existence of epigenetic marks on sperm genes, and there are no functional tests supporting the role of sperm epigenetic marking on embryonic gene expression. Here, we show that sperm is epigenetically programmed to regulate embryonic gene expression. By comparing the development of sperm- and spermatid-derived frog embryos, we show that the programming of sperm for successful development relates to its ability to regulate transcription of a set of developmentally important genes. During spermatid maturation into sperm, these genes lose H3K4me2/3 and retain H3K27me3 marks. Experimental removal of these epigenetic marks at fertilization de-regulates gene expression in the resulting embryos in a paternal chromatin-dependent manner. This demonstrates that epigenetic instructions delivered by the sperm at fertilization are required for correct regulation of gene expression in the future embryos. The epigenetic mechanisms of developmental programming revealed here are likely to relate to the mechanisms involved in transgenerational transmission of acquired traits. Understanding how parental experience can influence development of the progeny has broad potential for improving human health. PMID:27034506

  7. Sperm is epigenetically programmed to regulate gene transcription in embryos

    PubMed Central

    Teperek, Marta; Simeone, Angela; Gaggioli, Vincent; Miyamoto, Kei; Allen, George E.; Erkek, Serap; Kwon, Taejoon; Marcotte, Edward M.; Zegerman, Philip; Bradshaw, Charles R.; Peters, Antoine H.F.M.; Gurdon, John B.; Jullien, Jerome

    2016-01-01

    For a long time, it has been assumed that the only role of sperm at fertilization is to introduce the male genome into the egg. Recently, ideas have emerged that the epigenetic state of the sperm nucleus could influence transcription in the embryo. However, conflicting reports have challenged the existence of epigenetic marks on sperm genes, and there are no functional tests supporting the role of sperm epigenetic marking on embryonic gene expression. Here, we show that sperm is epigenetically programmed to regulate embryonic gene expression. By comparing the development of sperm- and spermatid-derived frog embryos, we show that the programming of sperm for successful development relates to its ability to regulate transcription of a set of developmentally important genes. During spermatid maturation into sperm, these genes lose H3K4me2/3 and retain H3K27me3 marks. Experimental removal of these epigenetic marks at fertilization de-regulates gene expression in the resulting embryos in a paternal chromatin-dependent manner. This demonstrates that epigenetic instructions delivered by the sperm at fertilization are required for correct regulation of gene expression in the future embryos. The epigenetic mechanisms of developmental programming revealed here are likely to relate to the mechanisms involved in transgenerational transmission of acquired traits. Understanding how parental experience can influence development of the progeny has broad potential for improving human health. PMID:27034506

  8. Formation of primary sperm conjugates in a haplogyne spider (Caponiidae, Araneae) with remarks on the evolution of sperm conjugation in spiders.

    PubMed

    Lipke, Elisabeth; Michalik, Peter

    2012-11-01

    Sperm conjugation, where two or more sperm are physically united, is a rare but widespread pheno-menon across the animal kingdom. One group well known for its different types of sperm conjugation are spiders. Particularly, haplogyne spiders show a high diversity of sperm traits. Besides individual cleistospermia, primary (synspermia) and secondary (coenospermia, "spermatophore") sperm conjugation occurs. However, the evolution of sperm conjugates and sperm is not understood in this group. Here, we look at how sperm are transferred in Caponiidae (Haplogynae) in pursuit of additional information about the evolution of sperm transfer forms in spiders. Additionally, we investigated the male reproductive system and spermatozoa using light- and transmission electron-microscopy and provide a 3D reconstruction of individual as of well as conjugated spermatozoa. Mature spermatozoa are characterized by an extremely elongated, helical nucleus resulting in the longest spider sperm known to date. At the end of spermiogenesis, synspermia are formed by complete fusion of four spermatids. Thus, synspermia might have evolved early within ecribellate Haplogynae. The fused sperm cells are surrounded by a prominent vesicular area. The function of the vesicular area remains still unknown but might be correlated with the capacitation process inside the female. Further phylogenetic and functional implications of the spermatozoa and sperm conjugation are discussed.

  9. Metabolic Rate Limits the Effect of Sperm Competition on Mammalian Spermatogenesis

    PubMed Central

    delBarco-Trillo, Javier; Tourmente, Maximiliano; Roldan, Eduardo R. S.

    2013-01-01

    Sperm competition leads to increased sperm production in many taxa. This response may result from increases in testes size, changes in testicular architecture or changes in the kinetics of spermatogenesis, but the impact of each one of these processes on sperm production has not been studied in an integrated manner. Furthermore, such response may be limited in species with low mass-specific metabolic rate (MSMR), i.e., large-bodied species, because they cannot process energy and resources efficiently enough both at the organismic and cellular levels. Here we compare 99 mammalian species and show that higher levels of sperm competition correlated with a) higher proportions of seminiferous tubules, b) shorter seminiferous epithelium cycle lengths (SECL) which reduce the time required to produce sperm, and c) higher efficiencies of Sertoli cells (involved in sperm maturation). These responses to sperm competition, in turn, result in higher daily sperm production, more sperm stored in the epididymides, and more sperm in the ejaculate. However, the two processes that require processing resources at faster rates (SECL and efficiency of Sertoli cells) only respond to sperm competition in species with high MSMR. Thus, increases in sperm production with intense sperm competition occur via a complex network of mechanisms, but some are constrained by MSMR. PMID:24069461

  10. Negative biomarker-based male fertility evaluation: sperm phenotypes associated with molecular-level anomalies

    PubMed Central

    Sutovsky, Peter; Aarabi, Mahmoud; Miranda-Vizuete, Antonio; Oko, Richard

    2015-01-01

    Biomarker-based sperm analysis elevates the treatment of human infertility and ameliorates reproductive performance in livestock. The negative biomarker-based approach focuses on proteins and ligands unique to defective spermatozoa, regardless of their morphological phenotype, lending itself to analysis by flow cytometry (FC). A prime example is the spermatid specific thioredoxin SPTRX3/TXNDC8, retained in the nuclear vacuoles and superfluous cytoplasm of defective human spermatozoa. Infertile couples with high semen SPTRX3 are less likely to conceive by assisted reproductive therapies (ART) and more prone to recurrent miscarriage while low SPTRX3 has been associated with multiple ART births. Ubiquitin, a small, proteolysis-promoting covalent posttranslational protein modifier is found on the surface of defective posttesticular spermatozoa and in the damaged protein aggregates, the aggresomes of spermiogenic origin. Semen ubiquitin content correlates negatively with fertility and conventional semen parameters, and with sperm binding of lectins LCA (Lens culinaris agglutinin; reveals altered sperm surface) and PNA (Arachis hypogaea/peanut agglutinin; reveals acrosomal malformation or damage). The Postacrosomal Sheath WWI Domain Binding Protein (PAWP), implicated in oocyte activation during fertilization, is ectopic or absent from defective human and animal spermatozoa. Consequently, FC-parameters of PAWP correlate with ART outcomes in infertile couples and with fertility in bulls. Assays based on the above biomarkers have been combined into multiplex FC semen screening protocols, and the surface expression of lectins and ubiquitin has been utilized to develop nanoparticle-based bull semen purification method validated by field artificial insemination trials. These advances go hand-in-hand with the innovation of FC-technology and genomics/proteomics-based biomarker discovery. PMID:25999356

  11. Reliable single sperm cryopreservation in Cell Sleepers for azoospermia management.

    PubMed

    Coetzee, K; Ozgur, K; Berkkanoglu, M; Bulut, H; Isikli, A

    2016-03-01

    Conventional sperm freezing methods perform best when freezing sperm samples containing at least hundreds of spermatozoa. In this severe male factor infertility case series, we examined the reproductive outcomes in 12 intracytoplasmic sperm injection cases where spermatozoa used were frozen in Cell Sleepers. Cell Sleepers are novel devices in which individual spermatozoa can be frozen in microdroplets. The case series included five men with obstructive azoospermia, six with nonobstructive azoospermia and one with cryptozoospermia, in whom microscopic sperm retrievals from testicular sperm extraction (TESE), micro-TESE extracts and a centrifugation procedure resulted in less than 50 spermatozoa. A total of 304 microscopically retrieved spermatozoa were frozen in 20 Cell Sleepers using a rapid manual cryopreservation method. A total of 179 mature oocytes were injected with recovered thawed spermatozoa, resulting in a fertilisation rate of 65.9% (118 of 179), with no total fertilisation failures. In 10 cases, an embryo transfer was performed, three on day 3 and seven on day 5, resulting in a per cycle pregnancy rate of 58.3% (seven of 12). Four of the pregnancies have progressed past 20 gestation weeks. The recovery and use of spermatozoa that were frozen in Cell Sleepers was uncomplicated and effective and eliminated the need to perform any microscopic sperm retrieval procedures on the day of oocyte collection. Modification of the routine sperm cryopreservation methodology to include the use of Cell Sleepers increases the range of sperm samples that can be effectively cryopreserved, to include men with severe male factor fertility.

  12. Molecular kinetics of proteins at the surface of porcine sperm before and during fertilization.

    PubMed

    Tsai, P S; Gadella, B M

    2009-01-01

    Fertilization is a decisive moment in life and enables the combination of the DNA from two gametes to ultimately form a new organism. The sperm surface, especially the head area, has distinguishable subdomains that are involved in distinct fertilization processes. It is known that the sperm head surface undergoes constant remodelling during epididymal maturation and migration in the male and female genital tract. But intriguingly, the identity, origin and spatial ordering of proteins at the sperm surface that are involved in mammalian fertilization are essentially unknown. This review deals with sperm surface protein modifications that are under somatic cell control. As soon as the sperm is released from the seminiferous tubules it is subjected to these modifications. These surface reorganisations continue until the sperm reside in the fallopian tube where they meet the oocyte and may fertilize it. Most likely, a selective process allows only functionally mature and intact sperm to optimally interact and fertilize the oocyte. Recent data suggest that even the perivitelline fluid is involved in sperm surface remodelling as it contains factors which could facilitate the first penetrating sperm to fertilize the oocyte. In this contribution, the kinetics of proteins at the sperm surface will be overviewed. Better understanding of this would help to design strategies to improve male fertility or to devise novel contraceptives.

  13. The small RNA content of human sperm reveals pseudogene-derived piRNAs complementary to protein-coding genes.

    PubMed

    Pantano, Lorena; Jodar, Meritxell; Bak, Mads; Ballescà, Josep Lluís; Tommerup, Niels; Oliva, Rafael; Vavouri, Tanya

    2015-06-01

    At the end of mammalian sperm development, sperm cells expel most of their cytoplasm and dispose of the majority of their RNA. Yet, hundreds of RNA molecules remain in mature sperm. The biological significance of the vast majority of these molecules is unclear. To better understand the processes that generate sperm small RNAs and what roles they may have, we sequenced and characterized the small RNA content of sperm samples from two human fertile individuals. We detected 182 microRNAs, some of which are highly abundant. The most abundant microRNA in sperm is miR-1246 with predicted targets among sperm-specific genes. The most abundant class of small noncoding RNAs in sperm are PIWI-interacting RNAs (piRNAs). Surprisingly, we found that human sperm cells contain piRNAs processed from pseudogenes. Clusters of piRNAs from human testes contain pseudogenes transcribed in the antisense strand and processed into small RNAs. Several human protein-coding genes contain antisense predicted targets of pseudogene-derived piRNAs in the male germline and these piRNAs are still found in mature sperm. Our study provides the most extensive data set and annotation of human sperm small RNAs to date and is a resource for further functional studies on the roles of sperm small RNAs. In addition, we propose that some of the pseudogene-derived human piRNAs may regulate expression of their parent gene in the male germline.

  14. The small RNA content of human sperm reveals pseudogene-derived piRNAs complementary to protein-coding genes

    PubMed Central

    Pantano, Lorena; Jodar, Meritxell; Bak, Mads; Ballescà, Josep Lluís; Tommerup, Niels; Oliva, Rafael; Vavouri, Tanya

    2015-01-01

    At the end of mammalian sperm development, sperm cells expel most of their cytoplasm and dispose of the majority of their RNA. Yet, hundreds of RNA molecules remain in mature sperm. The biological significance of the vast majority of these molecules is unclear. To better understand the processes that generate sperm small RNAs and what roles they may have, we sequenced and characterized the small RNA content of sperm samples from two human fertile individuals. We detected 182 microRNAs, some of which are highly abundant. The most abundant microRNA in sperm is miR-1246 with predicted targets among sperm-specific genes. The most abundant class of small noncoding RNAs in sperm are PIWI-interacting RNAs (piRNAs). Surprisingly, we found that human sperm cells contain piRNAs processed from pseudogenes. Clusters of piRNAs from human testes contain pseudogenes transcribed in the antisense strand and processed into small RNAs. Several human protein-coding genes contain antisense predicted targets of pseudogene-derived piRNAs in the male germline and these piRNAs are still found in mature sperm. Our study provides the most extensive data set and annotation of human sperm small RNAs to date and is a resource for further functional studies on the roles of sperm small RNAs. In addition, we propose that some of the pseudogene-derived human piRNAs may regulate expression of their parent gene in the male germline. PMID:25904136

  15. Sperm competition and the evolution of sperm design in mammals

    PubMed Central

    2011-01-01

    Background The influence of sperm competition upon sperm size has been a controversial issue during the last 20 years which remains unresolved for mammals. The hypothesis that, when ejaculates compete with rival males, an increase in sperm size would make sperm more competitive because it would increase sperm swimming speed, has generated contradictory results from both theoretical and empirical studies. In addition, the debate has extended to which sperm components should increase in size: the midpiece to accommodate more mitochondria and produce more energy to fuel motility, or the principal piece to generate greater propulsion forces. Results In this study we examined the influence of sperm competition upon sperm design in mammals using a much larger data set (226 species) than in previous analyses, and we corrected for phylogenetic effects by using a more complete and resolved phylogeny, and more robust phylogenetic control methods. Our results show that, as sperm competition increases, all sperm components increase in an integrated manner and sperm heads become more elongated. The increase in sperm length was found to be associated with enhanced swimming velocity, an adaptive trait under sperm competition. Conclusions We conclude that sperm competition has played an important role in the evolution of sperm design in mammals, and discuss why previous studies have failed to detect it. PMID:21232104

  16. Supporters of sperm

    PubMed Central

    Løvlie, Hanne

    2014-01-01

    The Biology of Spermatozoa (BoS) meetings have run on a biannual basis since the early 1990s. They are dedicated to the fascinating research topic of sperm and their complicated route to fertilization. The BoS meetings focus on sperm, but they also explore additional supporting factors important in fertilization, such as those present in seminal and ovarian fluid, as well as the genomic bases of sperm biology. Here, I present a report of the recent BoS meeting, and showcase some of the highlights of this year’s meeting. PMID:25225623

  17. Lipopolysaccharide Compromises Human Sperm Function by Reducing Intracellular cAMP.

    PubMed

    Li, Zhongyuan; Zhang, Dahu; He, Yuanqiao; Ding, Zhiyong; Mao, Fei; Luo, Tao; Zhang, Xiaoping

    2016-01-01

    A worldwide decline in the quality of human semen is currently occurring. In mammals, sperm are produced from diploid stem-cell spermatogonia by spermatogenesis in testes and become mature in epididymis. Nevertheless, these biological processes can be affected by Gram-negative bacterial infection mediated by lipopolysaccharide (LPS), the major endotoxin of Gram-negative bacteria. It is well known that LPS can disturb spermatogenesis and affect sperm maturation and quality in vivo. However, the effect of LPS on the ejaculated mature sperm in vitro remains unclear. Thus, this study aimed to assess the in vitro toxicity of LPS on human sperm function and to elucidate the underlying mechanism. Human sperm were incubated with LPS (0.1-100 μg/ml) for 1-12 h in vitro and, subsequently, sperm viability, motility and capacitation, and the acrosome reaction were examined. LPS dose-dependently inhibited total and progressive motility and the ability to move through a viscous medium of the sperm but did not affect sperm viability, capacitation, and the acrosome reaction. To explore the underlying mechanism of LPS's actions, we examined the effects of LPS on the intracellular concentrations of cyclic adenosine monophosphate (cAMP) and calcium ([Ca(2+)]i) and protein-tyrosine phosphorylation of human sperm, which are key regulators of human sperm function. LPS decreased intracellular cAMP dose-dependently but had no effect on [Ca(2+)]i and protein-tyrosine phosphorylation of human sperm. These findings suggest that LPS inhibits human sperm motility by decreasing intracellular cAMP. PMID:26782775

  18. Lipopolysaccharide Compromises Human Sperm Function by Reducing Intracellular cAMP.

    PubMed

    Li, Zhongyuan; Zhang, Dahu; He, Yuanqiao; Ding, Zhiyong; Mao, Fei; Luo, Tao; Zhang, Xiaoping

    2016-01-01

    A worldwide decline in the quality of human semen is currently occurring. In mammals, sperm are produced from diploid stem-cell spermatogonia by spermatogenesis in testes and become mature in epididymis. Nevertheless, these biological processes can be affected by Gram-negative bacterial infection mediated by lipopolysaccharide (LPS), the major endotoxin of Gram-negative bacteria. It is well known that LPS can disturb spermatogenesis and affect sperm maturation and quality in vivo. However, the effect of LPS on the ejaculated mature sperm in vitro remains unclear. Thus, this study aimed to assess the in vitro toxicity of LPS on human sperm function and to elucidate the underlying mechanism. Human sperm were incubated with LPS (0.1-100 μg/ml) for 1-12 h in vitro and, subsequently, sperm viability, motility and capacitation, and the acrosome reaction were examined. LPS dose-dependently inhibited total and progressive motility and the ability to move through a viscous medium of the sperm but did not affect sperm viability, capacitation, and the acrosome reaction. To explore the underlying mechanism of LPS's actions, we examined the effects of LPS on the intracellular concentrations of cyclic adenosine monophosphate (cAMP) and calcium ([Ca(2+)]i) and protein-tyrosine phosphorylation of human sperm, which are key regulators of human sperm function. LPS decreased intracellular cAMP dose-dependently but had no effect on [Ca(2+)]i and protein-tyrosine phosphorylation of human sperm. These findings suggest that LPS inhibits human sperm motility by decreasing intracellular cAMP.

  19. Ultrastructure of gametes and intracytoplasmic sperm injection: the significance of sperm morphology.

    PubMed

    Küpker, W; Schulze, W; Diedrich, K

    1998-04-01

    The aim of this study was to determine characteristic malformations of sperm ultrastructure in patients with severe subfertility undergoing intracytoplasmic sperm injection (ICSI). Although light microscopy (LM) can reveal major abnormalities of the three parts of the spermatozoon (head, mid-piece and flagellum), the various cell organelles of the spermatozoon and their fine structure remain unevaluated by LM. Insight into the submicroscopic organization of the spermatozoon and its complex organellar system may contribute to a better understanding of the preconditions for success or failure of fertilization. An in-depth evaluation of semen quality by transmission electron microscopy (TEM) can improve the diagnosis of male subfertility and can give substantial information about the fertilizing competence of spermatozoa. Thus, in this study 56 ejaculated sperm samples from patients with severe male subfertility or previous failed attempts at in-vitro fertilization were assessed by LM and TEM prior to ICSI to evaluate the most important sperm defects causing extreme subfertility. LM analysis was performed according to World Health Organization criteria. It could be confirmed that severe head defects are mostly involved in long-term infertility and fertilizing failure in classical IVF treatments. The most frequent head defects are disorders of the nuclear membranes and the acrosomal cap and disorganization of the chromatin structure. These defects of sperm fine structure seem to be associated with dysfunctional sperm-oocyte recognition, binding and fusion with the oolemma. Chromatin alterations and signs of decondensation or karyolysis are frequently associated with a deterioration of the nuclear membranes and may be due to impaired spermiogenesis. However, our results and the success of ICSI proved that severe sperm defects have no predictive value and do not impair the fertilization process, and also that the maturity of spermatozoa does not play an important role

  20. Comprehensive profiling of accessible surface glycans of mammalian sperm using a lectin microarray

    PubMed Central

    2014-01-01

    It is well known that cell surface glycans or glycocalyx play important roles in sperm motility, maturation and fertilization. A comprehensive profile of the sperm surface glycans will greatly facilitate both basic research (sperm glycobiology) and clinical studies, such as diagnostics of infertility. As a group of natural glycan binders, lectin is an ideal tool for cell surface glycan profiling. However, because of the lack of effective technology, only a few lectins have been tested for lectin-sperm binding profiles. To address this challenge, we have developed a procedure for high-throughput probing of mammalian sperm with 91 lectins on lectin microarrays. Normal sperm from human, boar, bull, goat and rabbit were collected and analyzed on the lectin microarrays. Positive bindings of a set of ~50 lectins were observed for all the sperm of 5 species, which indicated a wide range of glycans are on the surface of mammalian sperm. Species specific lectin bindings were also observed. Clustering analysis revealed that the distances of the five species according to the lectin binding profiles are consistent with that of the genome sequence based phylogenetic tree except for rabbit. The procedure that we established in this study could be generally applicable for sperm from other species or defect sperm from the same species. We believe the lectin binding profiles of the mammalian sperm that we established in this study are valuable for both basic research and clinical studies. PMID:24629138

  1. Large-male advantages associated with costs of sperm production in Drosophila hydei, a species with giant sperm.

    PubMed Central

    Pitnick, S; Markow, T A

    1994-01-01

    Males of the fruit fly Drosophila hydei were found to produce 23.47 +/- 0.46-mm-long spermatozoa, the longest ever described. No relationship was found between male body size and sperm length. We predicted that if these giant gametes are costly for males to produce, then correlations should exist between male body size, rates of sperm production, and fitness attributes associated with the production of sperm. Smaller males were found to make a greater relative investment in testicular tissue growth, even though they have shorter and thinner testes. Smaller males were also found to (i) be maturing fewer sperm bundles within the testes at any point in time than larger males, (ii) require a longer period of time post-eclosion to become reproductively mature, (iii) mate with fewer females, (iv) transfer fewer sperm per copulation, and (v) produce fewer progeny. The significance of these findings for body size-related fitness and the question of sperm size evolution are discussed. PMID:7937755

  2. Correlation study between sperm concentration, hyaluronic acid-binding capacity and sperm aneuploidy in Hungarian patients.

    PubMed

    Mokánszki, Attila; Molnár, Zsuzsanna; Ujfalusi, Anikó; Balogh, Erzsébet; Bazsáné, Zsuzsa Kassai; Varga, Attila; Jakab, Attila; Oláh, Éva

    2012-12-01

    Infertile men with low sperm concentration and/or less motile spermatozoa have an increased risk of producing aneuploid spermatozoa. Selecting spermatozoa by hyaluronic acid (HA) binding may reduce genetic risks such as chromosomal rearrangements and numerical aberrations. Fluorescence in-situ hybridization (FISH) has been used to evaluate the presence of aneuploidies. This study examined spermatozoa of 10 oligozoospermic, 9 asthenozoospermic, 9 oligoasthenozoospermic and 17 normozoospermic men by HA binding and FISH. Mean percentage of HA-bound spermatozoa in the normozoospermic group was 81%, which was significantly higher than in the oligozoospermic (P<0.001), asthenozoospermic (P<0.001) and oligoasthenozoospermic (P<0.001) groups. Disomy of sex chromosomes (P=0.014) and chromosome 17 (P=0.0019), diploidy (P=0.03) and estimated numerical chromosome aberrations (P=0.004) were significantly higher in the oligoasthenozoospermic group compared with the other groups. There were statistically significant relationships (P<0.001) between sperm concentration and HA binding (r=0.658), between sperm concentration and estimated numerical chromosome aberrations (r=-0.668) and between HA binding and estimated numerical chromosome aberrations (r=-0.682). HA binding and aneuploidy studies of spermatozoa in individual cases allow prediction of reproductive prognosis and provision of appropriate genetic counselling. Infertile men with normal karyotypes and low sperm concentrations and/or less motile spermatozoa have significantly increased risks of producing aneuploid (diminished mature) spermatozoa. Selecting spermatozoa by hyaluronic acid (HA) binding, based on a binding between sperm receptors for zona pellucida and HA, may reduce the potential genetic risks such as chromosomal rearrangements and numerical aberrations. In the present study we examined sperm samples of 45 men with different sperm parameters by HA-binding assay and fluorescence in-situ hybridization (FISH). Mean

  3. Tuning sperm chemotaxis.

    PubMed

    Guerrero, Adán; Wood, Christopher D; Nishigaki, Takuya; Carneiro, Jorge; Darszon, Alberto

    2010-10-01

    Sperm chemotaxis is a long-term puzzle and most of our knowledge comes from studying marine animals that are external fertilizers. Sperm are attracted by diffusible chemical factors (chemoattractants) released from the egg which redirect their swimming paths towards their source. This redirection is driven by increases in flagellar curvature that correlate with transient flagellar Ca(2+) increases. Recent experimental and modelling results provide insights into the signal flow underlying the translation of an external chemical gradient into an intracellular molecular and motor response. A fundamental element of sea-urchin sperm chemotaxis lies in the ability of these cells to suppress Ca(2+)-mediated increases in flagellar curvature while experiencing an increasing chemoattractant gradient. The article considers this new evidence and summarizes the known underlying cellular mechanisms and behavioural strategies that sperm use to locate and fertilize the oocyte.

  4. Sperm studies in anesthesiologists

    SciTech Connect

    Wyrobek, A.J.; Brodsky, J.; Gordon, l.; Moore, D.H., II; Watchmaker, G.; Cohen, E.N.

    1981-11-01

    Semen samples were collected from 46 anesthesiologists each of whom had worked a minimum of one year in hospital operating rooms ventilated with modern gas-scavenging devices. Samples collected from 26 beginning residents in anesthesiology served as controls. Concentrations of sperm and percentage of sperm having abnormal head shapes were determined for each sample. No significant differences were found between anesthesiologists and beginning residents. Limiting the analyses to men having no confounding factors (varicocele, recent illness, medications, heavy smoking, frequent sauna use) did not change the results. The sperm concentration and morphology in 13 men did not change signficantly after one year of exposure to anesthetic gases. However, the group of men who had one or more confounding factors (excluding exposure to anesthetic gases) showed significantly higher percentages of sperm abnormalities than did the group of men without such factors. These results suggest that limited exposure to anesthetic gases does not significantly affect sperm production as judged by changes in sperm concentration and morphology. These data are reassuring, but since the hospitals surveyed used modern gas-scavenging devices, men who are occupationally exposed to anesthetic gases without this protection should be studied for fuller assessment of the possible human spermatotoxic effects.

  5. Accessory sperm: a biomonitor of boar sperm fertilization capacity.

    PubMed

    Ardón, Florencia; Evert, Meike; Beyerbach, Martin; Weitze, Karl-Fritz; Waberski, Dagmar

    2005-04-15

    The number of accessory sperm found in the zona pellucida of porcine embryos was correlated to their individual quality and to the embryo quality range found within a single sow. Our goal was to determine whether accessory sperm counts provide semen evaluation with additional, useful information. Accessory sperm count was highest when only normal embryos were found in a given sow and diminished if oocytes or degenerated embryos were present (P<0.01). Within a given sow, normal embryos had higher (P<0.05) accessory sperm counts than degenerated embryos, although not when oocytes were also present. Fertilization capacity of sperm is optimal when only normal embryos are found in a given sow; this capacity is indicated by high accessory sperm counts. A decrease in fertilization capacity is reflected in diminishing accessory sperm counts. The boar had a significant effect (P<0.01) on accessory sperm count, but not on the percentage of normal embryos; this suggests that accessory sperm may be more sensitive indicators of the fertilization capacity of sperm than the percentage of normal embryos. We conclude that accessory sperm count can be used for the detection of compensable defects in sperm and is a valid parameter for assessing sperm fertilization capacity.

  6. Sperm ultrastructure, morphometry, and abnormal morphology in American black bears (Ursus americanus).

    PubMed

    Brito, L F C; Sertich, P L; Stull, G B; Rives, W; Knobbe, M

    2010-11-01

    The objective of this study was to describe sperm ultrastructure, morphometry, and abnormal morphology in American black bears. Electroejaculation was successful in 53.8% (7/13) of the attempts, but urine contamination was common. Epididymal sperm samples were also obtained from five bears. Sperm had a paddle-like head shape and the ultrastructure was similar to that of most other mammals. The most striking particularity of black bear sperm ultrastructure was a tightening of the nucleus in the equatorial region. Although the differences were not significant in all bears, the overall decrease in sperm nucleus dimensions during transport from the caput epididymis to the cauda suggested increasing compaction of the nucleus during maturation. For ejaculated sperm, nucleus length, width, and base width were 4.9, 3.7, and 1.8 μm, respectively, whereas sperm head length, width, and base width were 6.6, 4.8, and 2.3 μm, and midpiece, tail (including midpiece), and total sperm lengths were 9.8, 68.8, and 75.3 μm. Evaluation of sperm cytoplasmic droplets in the epididymis revealed that proximal droplets start migrating toward a distal position in the caput epididymis and that the process was mostly completed by the time sperm reached the cauda epididymis. The proportion of morphologically normal sperm in the ejaculate was 35.6%; the most prevalent sperm defects were distal cytoplasmic droplets and bent/coiled tails. The morphology of abnormal sperm and the underlying ultrastructural defects were similar to that in other large domestic animals thus suggesting similar underlying pathogenesis of specific sperm defects and similar effects on fertility. PMID:20708230

  7. Male sperm storage compromises sperm motility in guppies

    PubMed Central

    Gasparini, Clelia; Kelley, Jennifer L.; Evans, Jonathan P.

    2014-01-01

    Sperm senescence can have important evolutionary implications due to its deleterious effects on sperm quality and offspring performance. Consequently, it has been argued that polyandry (female multiple mating) may facilitate the selection of younger, and therefore competitively superior, sperm when ejaculates from multiple males compete for fertilization. Surprisingly, however, unequivocal evidence that sperm ageing influences traits that underlie sperm competitiveness is lacking. Here, we used a paired experimental design that compares sperm quality between ‘old’ and ‘young’ ejaculates from individual male guppies (Poecilia reticulata). We show that older sperm exhibit significant reductions in sperm velocity compared with younger sperm from the same males. We found no evidence that the brightness of the male's orange (carotenoid) spots, which are thought to signal resistance to oxidative stress (and thus age-related declines in sperm fitness), signals a male's ability to withstand the deleterious effects of sperm ageing. Instead, polyandry may be a more effective strategy for females to minimize the likelihood of being fertilized by aged sperm. PMID:25392314

  8. Male sperm storage compromises sperm motility in guppies.

    PubMed

    Gasparini, Clelia; Kelley, Jennifer L; Evans, Jonathan P

    2014-11-01

    Sperm senescence can have important evolutionary implications due to its deleterious effects on sperm quality and offspring performance. Consequently, it has been argued that polyandry (female multiple mating) may facilitate the selection of younger, and therefore competitively superior, sperm when ejaculates from multiple males compete for fertilization. Surprisingly, however, unequivocal evidence that sperm ageing influences traits that underlie sperm competitiveness is lacking. Here, we used a paired experimental design that compares sperm quality between 'old' and 'young' ejaculates from individual male guppies (Poecilia reticulata). We show that older sperm exhibit significant reductions in sperm velocity compared with younger sperm from the same males. We found no evidence that the brightness of the male's orange (carotenoid) spots, which are thought to signal resistance to oxidative stress (and thus age-related declines in sperm fitness), signals a male's ability to withstand the deleterious effects of sperm ageing. Instead, polyandry may be a more effective strategy for females to minimize the likelihood of being fertilized by aged sperm.

  9. Male sperm storage compromises sperm motility in guppies.

    PubMed

    Gasparini, Clelia; Kelley, Jennifer L; Evans, Jonathan P

    2014-11-01

    Sperm senescence can have important evolutionary implications due to its deleterious effects on sperm quality and offspring performance. Consequently, it has been argued that polyandry (female multiple mating) may facilitate the selection of younger, and therefore competitively superior, sperm when ejaculates from multiple males compete for fertilization. Surprisingly, however, unequivocal evidence that sperm ageing influences traits that underlie sperm competitiveness is lacking. Here, we used a paired experimental design that compares sperm quality between 'old' and 'young' ejaculates from individual male guppies (Poecilia reticulata). We show that older sperm exhibit significant reductions in sperm velocity compared with younger sperm from the same males. We found no evidence that the brightness of the male's orange (carotenoid) spots, which are thought to signal resistance to oxidative stress (and thus age-related declines in sperm fitness), signals a male's ability to withstand the deleterious effects of sperm ageing. Instead, polyandry may be a more effective strategy for females to minimize the likelihood of being fertilized by aged sperm. PMID:25392314

  10. Sperm Motility in Flow

    NASA Astrophysics Data System (ADS)

    Guasto, Jeffrey; Juarez, Gabriel; Stocker, Roman

    2012-11-01

    A wide variety of plants and animals reproduce sexually by releasing motile sperm that seek out a conspecific egg, for example in the reproductive tract for mammals or in the water column for externally fertilizing organisms. Sperm are aided in their quest by chemical cues, but must also contend with hydrodynamic forces, resulting from laminar flows in reproductive tracts or turbulence in aquatic habitats. To understand how velocity gradients affect motility, we subjected swimming sperm to a range of highly-controlled straining flows using a cross-flow microfluidic device. The motion of the cell body and flagellum were captured through high-speed video microscopy. The effects of flow on swimming are twofold. For moderate velocity gradients, flow simply advects and reorients cells, quenching their ability to cross streamlines. For high velocity gradients, fluid stresses hinder the internal bending of the flagellum, directly inhibiting motility. The transition between the two regimes is governed by the Sperm number, which compares the external viscous stresses with the internal elastic stresses. Ultimately, unraveling the role of flow in sperm motility will lead to a better understanding of population dynamics among aquatic organisms and infertility problems in humans.

  11. Career Maturity.

    ERIC Educational Resources Information Center

    Crites, John O.

    1973-01-01

    Research in the field of Career Maturity is reviewed and summarized, with particular attention to Super's Career Pattern Study, Gribbons and Lohnes' Career Development Study, and Crites' Vocational Development Project. Crites' organization and revision into a hierarchical structure of the five dimensions of vocational maturity proposed in Supers'…

  12. Virus Maturation

    PubMed Central

    Veesler, David; Johnson, John E.

    2013-01-01

    We examined virus maturation of selected non-enveloped and enveloped ssRNA viruses; retroviruses; bacteriophages and herpes virus. Processes associated with maturation in the RNA viruses range from subtle (noda and picornaviruses) to dramatic (tetraviruses and togaviruses). The elaborate assembly and maturation pathway of HIV is discussed in contrast to the less sophisticated but highly efficient processes associated with togaviruses. Bacteriophage assembly and maturation are discussed in general terms with specific examples chosen for emphasis. Finally the herpes viruses are compared with bacteriophages. The data support divergent evolution of noda, picorna and tetraviruses from a common ancestor and divergent evolution of alpha and flaviviruses from a common ancestor. Likewise, bacteriophages and herpes viruses almost certainly share a common ancestor in their evolution. Comparing all the viruses, we conclude that maturation is a convergent process that is required to solve conflicting requirements in biological dynamics and function. PMID:22404678

  13. Failed Sperm Development as a Reproductive Isolating Barrier between Species

    PubMed Central

    Wünsch, Lisa K.; Pfennig, Karin S.

    2013-01-01

    SUMMARY Hybrid male sterility is a common reproductive isolating barrier between species. Yet, little is known about the actual developmental causes of this phenomenon, especially in naturally hybridizing species. We sought to evaluate the developmental causes of hybrid male sterility, using spadefoot toads as our study system. Plains spadefoot toads (S. bombifrons) and Mexican spadefoot toads (S. multiplicata) hybridize where they co-occur in the southwestern USA. Hybrids are viable, but hybrid males suffer reduced fertility. We compared testes size and developmental stages of sperm cell maturation between hybrid males and males of each species. We found that testes of hybrid males did not differ in mean size from pure-species males. However, hybrids showed a greater range of within-individual variation in testes size than pure-species males. Moreover, although hybrids produced similar numbers of early stage sperm cells, hybrids produced significantly fewer mature spermatozoids than pure-species males. Interestingly, an introgressed individual produced numbers of live sperm comparable to pure-species males, but the majority of these sperm cells were abnormally shaped and non-motile. These results indicate that hybrid incompatibilities in late sperm development serve as a reproductive isolating barrier between species. The nature of this breakdown highlights the possibilities that hybrid males may vary in fertility and that fertility could possibly be recovered in introgressed males. PMID:24261446

  14. Quantitative analysis of radiation-induced changes in sperm morphology

    SciTech Connect

    Young, I.T.; Gledhill, B.L.; Lake, S.; Wyrobek, A.J.

    1982-09-01

    When developing spermatogenic cells are exposed to radiation, chemical carcinogens or mutagens, the transformation in the morphology of the mature sperm can be used to determine the severity of the exposure. In this study five groups of mice with three mice per group received testicular doses of X irradiation at dosage levels ranging from 0 rad to 120 rad. A random sample of 100 mature sperm per mouse was analyzed five weeks later for the quantitative morphologic transformation as a function of dosage level. The cells were stained with gallocyanin chrome alum (GCA) so that only the DNA in the sperm head was visible. The ACUity quantitative microscopy system at Lawrence Livermore National Laboratory was used to scan the sperm at a sampling density of 16 points per linear micrometer and with 256 brightness levels per point. The contour of each cell was extracted using conventional thresholding techniques on the high-contrast images. For each contour a variety of shape features was then computed to characterize the morphology of that cell. Using the control group and the distribution of their shape features to establish the variability of a normal sperm population, the 95% limits on normal morphology were established. Using only four shape features, a doubling dose of approximately 39 rad was determined. That is, at 39 rad exposure the percentage of abnormal cells was twice that occurring in the control population. This compared to a doubling dose of approximately 70 rad obtained from a concurrent visual procedure.

  15. An update on post-ejaculatory remodeling of the sperm surface before mammalian fertilization.

    PubMed

    Gadella, B M; Boerke, A

    2016-01-01

    The fusion of a sperm with an oocyte to form new life is a highly regulated event. The activation-also termed capacitation-of the sperm cell is one of the key preparative steps required for this process. Ejaculated sperm has to make a journey through the female uterus and oviduct before it can approach the oocyte. The oocyte at that moment also has become prepared to facilitate monospermic fertilization and block immediately thereafter the chance for polyspermic fertilization. Interestingly, ejaculated sperm is not properly capacitated and consequently is not yet able to fertilize the oocyte. During the capacitation process, the formation of competent lipid-protein domains on the sperm head enables sperm-cumulus and zona pellucida interactions. This sperm binding allows the onset for a cascade reaction ultimately resulting in oocyte-sperm fusion. Many different lipids and proteins from the sperm surface are involved in this process. Sperm surface processing already starts when sperm are liberated from the seminiferous tubules and is followed by epididymal maturation where the sperm cell surface is modified and loaded with proteins to ensure it is prepared for its fertilization task. Although cauda epididymal sperm can fertilize the oocyte IVF, they are coated with so-called decapacitation factors during ejaculation. The seminal plasma-induced stabilization of the sperm surface permits the sperm transit through the cervix and uterus but prevents sperm capacitation and thus inhibits fertilization. For IVF purposes, sperm are washed out of seminal plasma and activated to get rid of decapacitation factors. Only after capacitation, the sperm can fertilize the oocyte. In recent years, IVF has become a widely used tool to achieve successful fertilization in both the veterinary field and human medicine. Although IVF procedures are very successful, scientific knowledge is still far from complete when identifying all the molecular players and processes during the first

  16. Sperm function in affective illness.

    PubMed

    Amsterdam, J; Winokur, A; Levin, R

    1981-04-01

    There is evidence for functional changes in the hypothalamic-pituitary-gonadal axis of patients with affective disorders. Little is known concerning spermatogenesis or sperm function in depressed men. We systematically evaluated the sperm indices in a group of depressed males complaining of diminished libido, and a healthy control group. No differences were noted in sperm parameters between the groups.

  17. Oviducal sperm storage in poultry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hens are capable of fertilizing a daily succession of ovulated ova due to their ability to store sperm in the oviduct for several weeks. However, the precise biological mechanisms describing how sperm are selected and survive in the oviduct, and which sperm actually reach the site of fertilization c...

  18. Fusion of Boar Sperm with Nanoliposomes Prepared from Synthetic Phospholipids.

    PubMed

    Kasimanickam, V R; Buhr, M M

    2016-08-01

    Liposomes are artificial membrane vesicles that can be used to test and model the functions and interactions of various biological membranes, or as a carrier system to deliver biologically active substances into the cells, or to incorporate lipids into the plasma membrane of target cells to modify membrane structure-function relationships. Sperm plasma membrane undergoes lipid modification during maturation in epididymis and during capacitation in the female reproductive tract to facilitate fertilization. Natural variation in the amounts and composition of lipids in the sperm plasma membrane may also contribute to the species-specific sperm sensitivities to handling and storage conditions. Boar sperm are notoriously susceptible to membrane damage and are resistant to compositional alteration by artificial liposomes. This study used flow cytometry to demonstrate stable incorporation of nanoliposomes prepared from a complex mixture of various phospholipids (phosphatidylcholine : phosphatidylethanolamine : sphingomyelin : phosphatidylserine : phosphatidylinositol) with high fusion efficiency. Over 90% of sperm rapidly took up fluorescently labelled liposomes and retained the lipids for at least 60 min, in a significant time- and concentration-dependent manner. This unique fusion efficacy could be used to alter sperm plasma membrane composition and hence membrane-based functional responses. PMID:27217373

  19. Fusion of Boar Sperm with Nanoliposomes Prepared from Synthetic Phospholipids.

    PubMed

    Kasimanickam, V R; Buhr, M M

    2016-08-01

    Liposomes are artificial membrane vesicles that can be used to test and model the functions and interactions of various biological membranes, or as a carrier system to deliver biologically active substances into the cells, or to incorporate lipids into the plasma membrane of target cells to modify membrane structure-function relationships. Sperm plasma membrane undergoes lipid modification during maturation in epididymis and during capacitation in the female reproductive tract to facilitate fertilization. Natural variation in the amounts and composition of lipids in the sperm plasma membrane may also contribute to the species-specific sperm sensitivities to handling and storage conditions. Boar sperm are notoriously susceptible to membrane damage and are resistant to compositional alteration by artificial liposomes. This study used flow cytometry to demonstrate stable incorporation of nanoliposomes prepared from a complex mixture of various phospholipids (phosphatidylcholine : phosphatidylethanolamine : sphingomyelin : phosphatidylserine : phosphatidylinositol) with high fusion efficiency. Over 90% of sperm rapidly took up fluorescently labelled liposomes and retained the lipids for at least 60 min, in a significant time- and concentration-dependent manner. This unique fusion efficacy could be used to alter sperm plasma membrane composition and hence membrane-based functional responses.

  20. A Systematic Analysis of a Deep Mouse Epididymal Sperm Proteome

    SciTech Connect

    Chauvin, Theodore; Xie, Fang; Liu, Tao; Nicora, Carrie D.; Yang, Feng; Camp, David G.; Smith, Richard D.; Roberts, Kenneth P.

    2012-12-21

    Spermatozoa are highly specialized cells that, when mature, are capable of navigating the female reproductive tract and fertilizing an oocyte. The sperm cell is thought to be largely quiescent in terms of transcriptional and translational activity. As a result, once it has left the male reproductive tract, the sperm cell is essentially operating with a static population of proteins. It is therefore theoretically possible to understand the protein networks contained in a sperm cell and to deduce its cellular function capabilities. To this end we have performed a proteomic analysis of mouse sperm isolated from the cauda epididymis and have confidently identified 2,850 proteins, which is the most comprehensive sperm proteome for any species reported to date. These proteins comprise many complete cellular pathways, including those for energy production via glycolysis, β-oxidation and oxidative phosphorylation, protein folding and transport, and cell signaling systems. This proteome should prove a useful tool for assembly and testing of protein networks important for sperm function.

  1. [Sperm quality and selection].

    PubMed

    Cohen-Bacrie, P

    2008-08-01

    Selection of a live and morphologically normal spermatozoa is a fundamental stage in ICSI success because of its potential effects on early and late embryo development. In addition to the routine tests such as the spermogram and the spermocytogram, a number of tests have been developed for this purpose : the hyaluronic acid test, which measures the rate of DNA fragmentation using TUNEL (% of fragmented DNA) or electrophoresis separation of SPZ, SPZ evaluation using the FISH method, MSOME (motile sperm organelle morphology examination) techniques, et IMSI (intracytoplasmic morphologically selected sperm injection), which can evaluate the nuclear vacuoles, etc.

  2. Provisional bilateral symmetry in Xenopus eggs is established during maturation

    NASA Technical Reports Server (NTRS)

    Brown, E. E.; Margelot, K. M.; Danilchik, M. V.

    1994-01-01

    Dorsal-ventral patterning in the Xenopus egg becomes established midway through the first cell cycle during a 30 degree rotation of the subcortical yolk mass relative to the egg cortex. This 'rotation of symmetrisation' is microtubule dependent, and its direction is thought to be cued by the usually eccentric sperm centrosome. The fact that parthenogenetically activated eggs also undergo a directed rotation, despite the absence of a sperm centrosome, suggests that an endogenous asymmetry in the unfertilised egg supports the directed polymerisation of microtubules in the vegetal cortex, in the way that an eccentric sperm centrosome would in fertilised eggs. Consistent with this idea, we noticed that the maturation spot is usually located an average of more than 15 degrees from the geometric centre of the pigmented animal hemisphere. In parthenogenetically activated eggs, this eccentric maturation spot can be used to predict the direction of rotation. Although in most fertilised eggs the yolk mass rotates toward the sperm entry point (SEP) meridian, occasionally this relationship is perturbed significantly; in such eggs, the maturation spot is never on the same side of the egg as the SEP. In oocytes tilted 90 degrees from upright during maturation in vitro, the maturation spot developed 15 degrees or more from the centre of the pigmented hemisphere, always displaced towards the point on the equator that was up during maturation. This experimentally demonstrated lability is consistent with an off-axis oocyte orientation during oogenesis determining its eccentric maturation spot position, and, in turn, its endogenous rotational bias.

  3. Coupling sperm mediated gene transfer and sperm sorting techniques: a new perspective for swine transgenesis.

    PubMed

    De Cecco, Marco; Spinaci, Marcella; Zannoni, Augusta; Bernardini, Chiara; Seren, Eraldo; Forni, Monica; Bacci, Maria Laura

    2010-09-15

    Flow cytometric separation of X and Y chromosome-bearing spermatozoa has been demonstrated to be effective in pigs, allowing the use of boar sexed semen in in vitro trials. Sperm Mediated Gene Transfer (SMGT) is a widely used and efficient technique for the creation of transgenic animals. The present research intended to prove that it is possible to associate sperm sexing with the SMGT technique in order to speed up the assessment of homozygous lines of transgenic pigs. In the first experiment, the sorting protocol was modified in order to obtain the highest DNA uptake by sorted spermatozoa. In the second experiment, spermatozoa that had undergone only sperm sorting, only SMGT, or both procedures (Sorted-SMGT) were used for in in vitro fertilization of in vitro matured oocytes. In the third experiment, transformed blastocysts of the desired gender (male) were obtained with Sorted-SMGT in an in vitro fertilization trial. The method we developed here allowed us to produce transgenic swine blastocysts of pre-determined gender, giving a positive answer at the aim to couple SMGT and sperm sorting in swine, obtaining fertile spermatozoa able to produce transgenic embryos of pre-determined gender. PMID:20537690

  4. Cholecystokinin receptors regulate sperm protein tyrosine phosphorylation via uptake of HCO3-.

    PubMed

    Zhou, Yuchuan; Ru, Yanfei; Shi, Huijuan; Wang, Yanjiao; Wu, Bin; Upur, Halmurat; Zhang, Yonglian

    2015-10-01

    Cholecystokinin (CCK), a peptide hormone and a neurotransmitter, was detected in mature sperm two decades ago. However, the exact role of CCK and the types of CCK receptors (now termed CCK1 and CCK2) in sperm have not been identified. Here, we find that CCK1 and CCK2 receptors are immunolocalized to the acrosomal region of mature sperm. The antagonist of CCK1 or CCK2 receptor strongly activated the soluble adenylyl cyclase/cAMP/protein kinase A signaling pathway that drives sperm capacitation-associated protein tyrosine phosphorylation in dose- and time-dependent manners. But these actions of stimulation were abolished when sperm were incubated in the medium in the absence of HCO3-. Further investigation demonstrated that the inhibitor of CCK1 or CCK2 receptor could accelerate the uptake of HCO3- and significantly elevate the intracellular pH of sperm. Interestingly, the synthetic octapeptide of CCK (CCK8) showed the same action and mechanism as antagonists of CCK receptors. Moreover, CCK8 and the antagonist of CCK1 or CCK2 receptor were also able to accelerate human sperm capacitation-associated protein tyrosine phosphorylation by stimulating the influx of HCO3-. Thus, the present results suggest that CCK and its receptors may regulate sperm capacitation-associated protein tyrosine phosphorylation by modulating the uptake of HCO3-.

  5. Aneuploidy detection in human sperm nuclei using PRINS technique

    SciTech Connect

    Girardet, A.; Coignet, L.; Andreo, B.

    1996-08-23

    Rapid and specific identification of chromosomes can be attained in situ using the PRimed IN Situ (PRINS) labelling technique. We have adapted this technique to mature human sperm in combination with a protocol for simultaneous decondensation and denaturation of sperm nuclei. This strategy allowed us to obtain double labelling of human spermatozoa in a <2-hr reaction. In the present study, we report the estimates of disomy for chromosomes 3, 7, 10, 11, and 17 on 64,642 spermatozoa from 2 normal males. The incidences of disomy ranged from 0.28-0.34%. There were no significant interindividual or interchromosomal differences in disomy rates. 27 refs., 1 fig., 3 tabs.

  6. Fertilization in a chiton: acrosome-mediated sperm-egg fusion.

    PubMed

    Buckland-Nicks, J; Koss, R; Chia, F S

    1988-11-01

    Contrary to the widely accepted view that chiton sperm lack acrosomes and that fertilization in this group occurs via a micropyle, we demonstrate here that fertilization in Tonicella lineata occurs by acrosome-mediated sperm-egg fusion. The acrosome is a small vesicle containing two granules located at the tip of the sperm. The eggs have an elaborate hull (= chorion), which is formed into cupules that remain covered by follicle cells until maturity. When dissected ripe eggs were exposed to sperm in vitro, the sperm were attracted only to open cupules, inside which they swam through one of seven channels to the base where they penetrated the hull. The acrosome fired on contact with, or in, the hull, and during passage through it the apical granule was exhausted while the basal granule was exposed. If sperm contacted follicle cells between the cupules the acrosome did not react. The vitelline layer beneath the hull contains pores arranged in a regular pattern. Embedded in the base of each pore is an egg microvillus. Having penetrated the hull the sperm anterior filament located a pore and fused with the tip of the egg microvillus projecting into it. This created a membranous tube, through which the sperm nucleus was injected into the egg. The egg membrane appeared to be raised up into a small fertilization cone around the penetrating sperm, the vitelline layer became slightly elevated, and some cortical granules were released by exocytosis.

  7. Recovery and cryopreservation of epididymal sperm from agouti (Dasiprocta aguti) using powdered coconut water (ACP-109c) and Tris extenders.

    PubMed

    Silva, M A; Peixoto, G C X; Santos, E A A; Castelo, T S; Oliveira, M F; Silva, A R

    2011-10-01

    The objective was to compare the use of powdered coconut water (ACP-109c; ACP Biotecnologia, Fortaleza, CE, Brazil) and Tris extenders for recovery and cryopreservation of epididymal sperm from agouti. The caudae epididymus and proximal ductus deferens from 10 sexually mature agoutis were subjected to retrograde washing using ACP-109c (ACP Biotecnologia) or Tris. Epididymal sperm were evaluated for motility, vigor, sperm viability, membrane integrity, and morphology. Samples were centrifuged, and extended in the same diluents plus egg yolk (20%) and glycerol (6%), frozen in liquid nitrogen, and subsequently thawed at 37°C for 1 min, followed by re-evaluation of sperm characteristics. The two extenders were similarly efficient for epididymal recovery, with regard to the number and quality of sperm recovered. However, for both extenders, sperm quality decreased (P < 0.05) after centrifugation and dilution. After sperm cryopreservation and thawing, there were (mean ± SEM) 26.5 ± 2.6% motile sperm with 2.6 ± 0.2 vigor in the ACP-109c (ACP Biotecnologia) group, which was significantly better than 9.7 ± 2.6% motile sperm with 1.2 ± 0.3 vigor in Tris. In conclusion, agouti epididymal sperm were successfully recovered using either ACP-109c (ACP Biotecnologia) or Tris extenders; however, ACP-109c (ACP Biotecnologia) was a significantly better extender for processing and cryopreserving these sperm.

  8. The effects of cryopreservation on the morphometric dimensions of Iberian red deer (Cervus elaphus hispanicus) epididymal sperm heads.

    PubMed

    Esteso, M C; Fernández-Santos, M R; Soler, A J; Montoro, V; Quintero-Moreno, A; Garde, J J

    2006-06-01

    Computer-automated sperm-head morphometry was used in this study to determine the effects of cryopreservation on red deer sperm-head morphometry. Epididymal sperm samples were collected from 40 mature stags and were divided. One portion was diluted at room temperature in a Tris-citrate egg yolk medium, containing 6% glycerol. A microscope slide was prepared from single extended sperm samples prior to freezing. The remainder of each sample was frozen in nitrogen vapours. After thawing, sperm smears were prepared as described above. All slides were air dried and stained with Hemacolor. The sperm-head dimensions for length, width, area, perimeter and shape factor (length/width), for a minimum of 135 spermatozoa were determined for each slide by means of the Sperm-Class Analyser (SCA). Firstly, our results show that cryopreservation substantially reduced (p < 0.001) sperm motility and plasma membrane and acrosome integrities. In addition, sperm heads were significantly smaller in cryopreserved spermatozoa than in the companion extended samples for area (32.05 microm2 vs 32.56 microm2; p < 0.05), length (8.46 microm vs 8.53 microm; p < 0.0001) and shape factor (1.833 vs 1.849; p < 0.0001) for all stags. These differences were found within 29 of 40 stags (75%) for at least three of the morphometric parameters. The individual variability (CV) of sperm head measurements from extended samples was negatively correlated (p < 0.005) with the per cent of change in sperm head measurements after cryopreservation for area (r = -0.465), width (r = -0.483) and perimeter (r = -0.375). Thus, the lower the sperm head variability in the extended samples, the greater the sperm change as a consequence of the cryopreservation. These results suggest that the variability (heterogeneity) in sperm head dimensions of individual stags may be a good indicator of sperm freezability.

  9. Interspecific androgenetic restoration of rosy barb using cadaveric sperm.

    PubMed

    Kirankumar, S; Pandian, T J

    2004-02-01

    Interspecific androgenetic rosy barb (Puntius conchonius) was generated using its cadaveric (-20 degrees C) or fresh sperm to activate nuclear genome inactivated oocytes of gray tiger barb (Puntius tetrazona). UV irradiation was used to inactivate nuclear genome of tiger barb oocytes. Thermal shock restored diploidy of rosy barb in the oocytes of tiger barb. Survival of androgenotes was 14% or 7% when fresh or cadaveric sperm was used. The diploid or haploid nuclear genome of rosy barb, individually or jointly with that of tiger barb, regulated the time sequence of embryonic development in an alien cytoplasm of tiger barb oocytes. Androgenetic males (Y2Y2) attained sexual maturity earlier and had significantly higher gonadosomatic index and sperm concentration, albeit suffering a slight decrease in fertilizing ability. Conversely, androgenetic females (X2X2) suffered extended interspawning period, reduced fecundity, and poor hatchability of their progenies. These results are discussed with respect to their significance for conservation biology. PMID:15060603

  10. Proteomics and the genetics of sperm chromatin condensation

    PubMed Central

    Oliva, Rafael; Castillo, Judit

    2011-01-01

    Spermatogenesis involves extremely marked cellular, genetic and chromatin changes resulting in the generation of the highly specialized sperm cell. Proteomics allows the identification of the proteins that compose the spermatogenic cells and the study of their function. The recent developments in mass spectrometry (MS) have markedly increased the throughput to identify and to study the sperm proteins. Catalogs of thousands of testis and spermatozoan proteins in human and different model species are becoming available, setting up the basis for subsequent research, diagnostic applications and possibly the future development of specific treatments. The present review intends to summarize the key genetic and chromatin changes at the different stages of spermatogenesis and in the mature sperm cell and to comment on the presently available proteomic studies. PMID:21042303

  11. Sexing sperm of domestic animals.

    PubMed

    Espinosa-Cervantes, Román; Córdova-Izquierdo, Alejandro

    2013-01-01

    The ability to preselect or predetermine the sex of offspring prior to conception is a highly desired technological tool for assisted female breeding programs specifically for milk production, and in males, for meat production and increasing livestock numbers. The current technology is based on the well-known differences in X- and Y-sperm in the amount of DNA. The technology uses modified flow cytometric instrumentation for sorting X- and Y-bearing sperm. The method can be validated on the basis of live births, laboratory reanalysis of sorted sperm for DNA content, and embryo biopsy for sex determination. Currently, the sex of animals has been predetermined with 90 % accuracy by sexing spermatozoa. In the bovine breeding industry, flow cytometric sperm sexing has not fulfilled its original promise. Sexed sperm doses are too expensive for widespread application while the fertility of sexed sperm doses is lower than unsexed ones. Essentially all bovine sexed semen is frozen and then applied through artificial insemination (AI) or in vitro fertilization. There is still a need in the animal breeding industry to develop a technique for sperm sexing that provides sufficient spermatozoa for AI doses, does not compromise sperm fertility, and is widely applicable to a range of species. In this review, we will summarize the current state-of-the-art in sex preselection in domestic animals and some wildlife species using flow cytometric sperm-sorting of X from Y sperm based on DNA differences.

  12. Sexing sperm of domestic animals.

    PubMed

    Espinosa-Cervantes, Román; Córdova-Izquierdo, Alejandro

    2013-01-01

    The ability to preselect or predetermine the sex of offspring prior to conception is a highly desired technological tool for assisted female breeding programs specifically for milk production, and in males, for meat production and increasing livestock numbers. The current technology is based on the well-known differences in X- and Y-sperm in the amount of DNA. The technology uses modified flow cytometric instrumentation for sorting X- and Y-bearing sperm. The method can be validated on the basis of live births, laboratory reanalysis of sorted sperm for DNA content, and embryo biopsy for sex determination. Currently, the sex of animals has been predetermined with 90 % accuracy by sexing spermatozoa. In the bovine breeding industry, flow cytometric sperm sexing has not fulfilled its original promise. Sexed sperm doses are too expensive for widespread application while the fertility of sexed sperm doses is lower than unsexed ones. Essentially all bovine sexed semen is frozen and then applied through artificial insemination (AI) or in vitro fertilization. There is still a need in the animal breeding industry to develop a technique for sperm sexing that provides sufficient spermatozoa for AI doses, does not compromise sperm fertility, and is widely applicable to a range of species. In this review, we will summarize the current state-of-the-art in sex preselection in domestic animals and some wildlife species using flow cytometric sperm-sorting of X from Y sperm based on DNA differences. PMID:22829354

  13. Sperm competition and ejaculate economics.

    PubMed

    Parker, Geoff A; Pizzari, Tommaso

    2010-11-01

    Sperm competition was identified in 1970 as a pervasive selective force in post-copulatory sexual selection that occurs when the ejaculates of different males compete to fertilise a given set of ova. Since then, sperm competition has been much studied both empirically and theoretically. Because sperm competition often favours large ejaculates, an important challenge has been to understand the evolution of strategies through which males invest in sperm production and economise sperm allocation to maximise reproductive success under competitive conditions. Sperm competition mechanisms vary greatly, depending on many factors including the level of sperm competition, space constraints in the sperm competition arena, male mating roles, and female influences on sperm utilisation. Consequently, theoretical models of ejaculate economics are complex and varied, often with apparently conflicting predictions. The goal of this review is to synthesise the theoretical basis of ejaculate economics under sperm competition, aiming to provide empiricists with categorised model assumptions and predictions. We show that apparent contradictions between older and newer models can often be reconciled and there is considerable consensus in the predictions generated by different models. We also discuss qualitative empirical support for some of these predictions, and detail quantitative matches between predictions and observations that exist in the yellow dung fly. We argue that ejaculate economic theory represents a powerful heuristic to explain the diversity in ejaculate traits at multiple levels: across species, across males and within individual males. Future progress requires greater understanding of sperm competition mechanisms, quantification of trade-offs between ejaculate allocation and numbers of matings gained, further knowledge of mechanisms of female sperm selection and their associated costs, further investigation of non-sperm ejaculate effects, and theoretical integration of

  14. Modification of sperm quality after sexual abstinence in Seba's short-tailed bat, Carollia perspicillata.

    PubMed

    Wesseling, Charlotte; Fasel, Nicolas; Richner, Heinz; Helfenstein, Fabrice

    2016-05-01

    In polygynous mating systems, few males have stable access to sexual mates. With an expected higher copulation rate, harem males may deplete seminal fluids or increase epididymal sperm maturation, generating poor sperm quality. In a first study, we reported a higher sperm quality in sneaker males of Carollia perspicillata To test whether the lower sperm quality observed in harem males was generated by an elevated copulation rate, we temporarily removed males of both social statuses from the colony. We thus assessed status-related changes of sperm quality resulting from sexual abstinence. Moreover, released from territory and female guarding, harem males were expected to show a reduction in somatic costs. On the basis of sperm competition models, we predicted a higher resource investment in the ejaculate with the reduction of pre-copulatory efforts. In line with our predictions, sperm quality of harem males improved significantly in contrast to sneaker males, whose sperm quality did not change. Without an increase in ejaculate lipid peroxidation, our results also provide evidence that the duration of sexual abstinence was not sufficient to generate sperm oxidative damage through senescence. Harem males did not show a reduction in blood lipid peroxidation or in the ratio of oxidized to reduced glutathione. In line with the maintenance of these somatic costs, harem males did not invest more superoxide dismutase to the ejaculate to maintain sperm quality. Our results suggest that a difference in copulation rate rather than an adaptation to sperm competition provides sneaker males with higher sperm quality in C. perspicillata. PMID:27208034

  15. Unconventional endocannabinoid signaling governs sperm activation via the sex hormone progesterone.

    PubMed

    Miller, Melissa R; Mannowetz, Nadja; Iavarone, Anthony T; Safavi, Rojin; Gracheva, Elena O; Smith, James F; Hill, Rose Z; Bautista, Diana M; Kirichok, Yuriy; Lishko, Polina V

    2016-04-29

    Steroids regulate cell proliferation, tissue development, and cell signaling via two pathways: a nuclear receptor mechanism and genome-independent signaling. Sperm activation, egg maturation, and steroid-induced anesthesia are executed via the latter pathway, the key components of which remain unknown. Here, we present characterization of the human sperm progesterone receptor that is conveyed by the orphan enzyme α/β hydrolase domain-containing protein 2 (ABHD2). We show that ABHD2 is highly expressed in spermatozoa, binds progesterone, and acts as a progesterone-dependent lipid hydrolase by depleting the endocannabinoid 2-arachidonoylglycerol (2AG) from plasma membrane. The 2AG inhibits the sperm calcium channel (CatSper), and its removal leads to calcium influx via CatSper and ensures sperm activation. This study reveals that progesterone-activated endocannabinoid depletion by ABHD2 is a general mechanism by which progesterone exerts its genome-independent action and primes sperm for fertilization. PMID:26989199

  16. Unconventional endocannabinoid signaling governs sperm activation via the sex hormone progesterone.

    PubMed

    Miller, Melissa R; Mannowetz, Nadja; Iavarone, Anthony T; Safavi, Rojin; Gracheva, Elena O; Smith, James F; Hill, Rose Z; Bautista, Diana M; Kirichok, Yuriy; Lishko, Polina V

    2016-04-29

    Steroids regulate cell proliferation, tissue development, and cell signaling via two pathways: a nuclear receptor mechanism and genome-independent signaling. Sperm activation, egg maturation, and steroid-induced anesthesia are executed via the latter pathway, the key components of which remain unknown. Here, we present characterization of the human sperm progesterone receptor that is conveyed by the orphan enzyme α/β hydrolase domain-containing protein 2 (ABHD2). We show that ABHD2 is highly expressed in spermatozoa, binds progesterone, and acts as a progesterone-dependent lipid hydrolase by depleting the endocannabinoid 2-arachidonoylglycerol (2AG) from plasma membrane. The 2AG inhibits the sperm calcium channel (CatSper), and its removal leads to calcium influx via CatSper and ensures sperm activation. This study reveals that progesterone-activated endocannabinoid depletion by ABHD2 is a general mechanism by which progesterone exerts its genome-independent action and primes sperm for fertilization.

  17. Sperm, Clinics, and Parenthood.

    PubMed

    Brandt, Reuven

    2016-10-01

    In this article I examine a recent approach to regulating assisted reproduction, whereby use of some kind of medical intervention 'triggers' laws governing legal parenthood that are more favourable to intending parents and sperm providers. I argue that although perhaps an improvement on the previous legal framework, these laws are problematic for three important reasons. First, they are prone to violating parental rights and unjustly imposing substantial burdens on individuals. Second, they are discriminatory. Third, even if we take a pragmatic approach to the question of parenthood in these cases, these laws fail to properly consider the welfare interests of children. Finally, I conclude by showing that my argument does not entail adopting a laissez-fair attitude to conception using third-party sperm. PMID:27523389

  18. Sperm, Clinics, and Parenthood.

    PubMed

    Brandt, Reuven

    2016-10-01

    In this article I examine a recent approach to regulating assisted reproduction, whereby use of some kind of medical intervention 'triggers' laws governing legal parenthood that are more favourable to intending parents and sperm providers. I argue that although perhaps an improvement on the previous legal framework, these laws are problematic for three important reasons. First, they are prone to violating parental rights and unjustly imposing substantial burdens on individuals. Second, they are discriminatory. Third, even if we take a pragmatic approach to the question of parenthood in these cases, these laws fail to properly consider the welfare interests of children. Finally, I conclude by showing that my argument does not entail adopting a laissez-fair attitude to conception using third-party sperm.

  19. Turbulence of swarming sperm

    NASA Astrophysics Data System (ADS)

    Creppy, Adama; Praud, Olivier; Druart, Xavier; Kohnke, Philippa L.; Plouraboué, Franck

    2015-09-01

    Collective motion of self-sustained swarming flows has recently provided examples of small-scale turbulence arising where viscous effects are dominant. We report the first observation of universal enstrophy cascade in concentrated swarming sperm consistent with a body of evidence built from various independent measurements. We found a well-defined k-3 power-law decay of a velocity field power spectrum and relative dispersion of small beads consistent with theoretical predictions in 2D turbulence. Concentrated living sperm displays long-range, correlated whirlpool structures of a size that provides an integral scale of turbulence. We propose a consistent explanation for this quasi-2D turbulence based on self-structured laminated flow forced by steric interactions and alignment, a state of active matter that we call "swarming liquid crystal." We develop scaling arguments consistent with this interpretation.

  20. Mammalian Sperm Fertility Related Proteins

    PubMed Central

    Ashrafzadeh, Ali; Karsani, Saiful Anuar; Nathan, Sheila

    2013-01-01

    Infertility is an important aspect of human and animal reproduction and still presents with much etiological ambiguity. As fifty percent of infertility is related to the male partner, molecular investigations on sperm and seminal plasma can lead to new knowledge on male infertility. Several comparisons between fertile and infertile human and other species sperm proteome have shown the existence of potential fertility markers. These proteins have been categorized into energy related, structural and other functional proteins which play a major role in sperm motility, capacitation and sperm-oocyte binding. The data from these studies show the impact of sperm proteome studies on identifying different valuable markers for fertility screening. In this article, we review recent development in unraveling sperm fertility related proteins. PMID:24151436

  1. Cytometry of mammalian sperm

    SciTech Connect

    Gledhill, B.L.

    1983-10-11

    Male germ cells respond dramatically to a variety of insults and are important reproductive dosimeters. Semen analyses are very useful in studies on the effects of drugs, chemicals, and environmental hazards on testicular function, male fertility and heritable germinal mutations. The accessibility of male cells makes them well suited for analytical cytology. We might automate the process of determining sperm morphology but should not do so solely for increased speed. Rather, richer tangible benefits will derive from cytometric evaluation through increased sensitivity, reduced subjectivity, standardization between investigators and laboratories, enhanced archival systems, and the benefits of easily exchanged standardized data. Inroads on the standardization of assays for motility and functional integrity are being made. Flow cytometric analysis of total DNA content of individual sperm is an insensitive means to detect exposure to reproductive toxins because of the small size and low frequency of the DNA content errors. Flow cytometry can be applied to determine the proportions of X- and Y-sperm in semen samples.

  2. Sperm function test

    PubMed Central

    Talwar, Pankaj; Hayatnagarkar, Suryakant

    2015-01-01

    With absolute normal semen analysis parameters it may not be necessary to shift to specialized tests early but in cases with borderline parameters or with history of fertilization failure in past it becomes necessary to do a battery of tests to evaluate different parameters of spermatozoa. Various sperm function tests are proposed and endorsed by different researchers in addition to the routine evaluation of fertility. These tests detect function of a certain part of spermatozoon and give insight on the events in fertilization of the oocyte. The sperms need to get nutrition from the seminal plasma in the form of fructose and citrate (this can be assessed by fructose qualitative and quantitative estimation, citrate estimation). They should be protected from the bad effects of pus cells and reactive oxygen species (ROS) (leukocyte detection test, ROS estimation). Their number should be in sufficient in terms of (count), structure normal to be able to fertilize eggs (semen morphology). Sperms should have intact and functioning membrane to survive harsh environment of vagina and uterine fluids (vitality and hypo-osmotic swelling test), should have good mitochondrial function to be able to provide energy (mitochondrial activity index test). They should also have satisfactory acrosome function to be able to burrow a hole in zona pellucida (acrosome intactness test, zona penetration test). Finally, they should have properly packed DNA in the nucleus to be able to transfer the male genes (nuclear chromatic decondensation test) to the oocyte during fertilization. PMID:26157295

  3. Quantitative analysis of flagellar proteins in Drosophila sperm tails.

    PubMed

    Mendes Maia, Teresa; Paul-Gilloteaux, Perrine; Basto, Renata

    2015-01-01

    The cilium has a well-defined structure, which can still accommodate some morphological and molecular composition diversity to suit the functional requirements of different cell types. The sperm flagellum of the fruit fly Drosophila melanogaster appears as a good model to study the genetic regulation of axoneme assembly and motility, due to the wealth of genetic tools publically available for this organism. In addition, the fruit fly's sperm flagellum displays quite a long axoneme (∼1.8mm), which may facilitate both histological and biochemical analyses. Here, we present a protocol for imaging and quantitatively analyze proteins, which associate with the fly differentiating, and mature sperm flagella. We will use as an example the quantification of tubulin polyglycylation in wild-type testes and in Bug22 mutant testes, which present defects in the deposition of this posttranslational modification. During sperm biogenesis, flagella appear tightly bundled, which makes it more challenging to get accurate measurements of protein levels from immunostained specimens. The method we present is based on the use of a novel semiautomated, macro installed in the image processing software ImageJ. It allows to measure fluorescence levels in closely associated sperm tails, through an exact distinction between positive and background signals, and provides background-corrected pixel intensity values that can directly be used for data analysis. PMID:25837396

  4. [Do phospholipases, key enzymes in sperm physiology, represent therapeutic challenges?].

    PubMed

    Arnoult, Christophe; Escoffier, Jessica; Munch, Léa; Pierre, Virginie; Hennebicq, Sylviane; Lambeau, Gérard; Ray, Pierre

    2012-05-01

    The spermatozoon is one of the most differentiated cells in mammals and its production requires an extremely complex machinery. Subtle but critical molecular changes take place during capacitation, which comprises the last series of maturation steps that naturally occur between the cauda epididymidis where spermatozoa are stored and their ultimate destination inside the oocyte. Phospholipases, by hydrolyzing various phospholipids, have been found to be critical in sperm processes such as 1) the control of flagellum beats, 2) capacitation - the molecular transformations preparing the sperm for fertilization, 3) acrosome reaction and 4) oocyte activation by eliciting calcium oscillations. The emerging important role of phospholipases is also emphasized by the fact that alterations of sperm lipids can lead to infertility. Phospholipases may represent valuable targets to develop anti- and pro-fertility drugs. Results obtained in mice are encouraging, since treatment of sperm with recombinant sPLA(2) of group X, known to be involved in capacitation, improves fertilization in vitro, while co-injection of PLCζ RNA with infertile sperm restores oocyte activation. PMID:22643005

  5. Factors influencing boar sperm cryosurvival.

    PubMed

    Roca, J; Hernández, M; Carvajal, G; Vázquez, J M; Martínez, E A

    2006-10-01

    Optimal sperm cryopreservation is a prerequisite for the sustainable commercial application of frozen-thawed boar semen for AI. Three experiments were performed to identify factors influencing variability of postthaw sperm survival among 464 boar ejaculates. Sperm-rich ejaculate fractions were cryopre-served using a standard freezing-thawing procedure for 0.5-mL plastic straws and computer-controlled freezing equipment. Postthaw sperm motility (assessed with a computer-assisted semen analysis system) and viability (simultaneously probed by flow cytometry analysis after triple-fluorescent stain), evaluated 30 and 150 min postthaw, were used to estimate the success of cryopreservation. In the first experiment, 168 unselected ejaculates (1 ejaculate/boar), from boars of 6 breeds with a wide age range (8 to 48 mo), were cryopreserved over a 12-mo period to evaluate the predictive value of boar (breed and age), semen collection, transport variables (season of ejaculate collection, interval between collections, and ejaculate temperature exposure), initial semen traits, and sperm quality before freezing on sperm survival after freezing-thawing. In Exp. 2, 4 ejaculates from each of 29 boars, preselected according to their initial semen traits and sperm quality before freezing, were collected and frozen over a 6-mo period to evaluate the influence of interboar and intraboar ejaculate variability in the survival of sperm after cryopreservation. In Exp. 3, 12 ejaculates preselected as for Exp. 2, from each of 15 boars with known good sperm cryosurvival, were collected and frozen over a 12-mo period to estimate the sustainability of sperm cryosurvival between ejaculates over time. Boar and semen collection and transport variables were not predictive of sperm cryosurvival among ejaculates. Initial semen traits and sperm quality variables observed before freezing explained 23.2 and 10.9%, respectively, of the variation in postthaw sperm motility and viability. However, more that

  6. Relationship of seminal plasma antioxidants and serum male hormones with sperm chromatin status in male factor infertility.

    PubMed

    Lakpour, Niknam; Mahfouz, Reda Z; Akhondi, Mohammad Mehdi; Agarwal, Ashok; Kharrazi, Hadi; Zeraati, Hojjat; Amirjannati, Naser; Sadeghi, Mohammad Reza

    2012-10-01

    We explored the relationship between sperm chromatin integrity, hormone levels, seminal plasma total antioxidant capacity (TAC), and routine sperm parameters in men with male factor (MF, n = 81) and non-male factor (NMF, n = 52) infertility. Semen and blood were collected and examined from men undergoing evaluation for infertility in the Avicenna Infertility Clinic. We have examined each patient for serum hormones (LH, FSH, E2, DHEA), sperm chromatin damage, level of protamination and seminal plasma TAC. Levels of FSH, LH, sperm chromatin damage, and abnormal protamination were significantly higher in MF vs. NMF groups (p < 0.001). Sperm chromatin damage was correlated with percentage of CMA(3)- positive sperm (r = 0.64, p < 0.001) and with sperm concentration (r = -0.36, p < 0.001), motility (r = -0.21, p < 0.05), and morphologically normal spermatozoa (r = -0.29, p < 0.001). Linear regression showed sperm chromatin damage was related to percentage of CMA(3)- positive sperm (p < 0.001) in ungrouped patients. It was related to both percentage of CMA(3)- positive sperm and serum DHEA in the MF group (p < 0.001 and p < 0.05, respectively). Sperm chromatin maturity assessed by CMA(3) test was inversely related to sperm chromatin damage assessed by the toludine blue assay. Male factor infertility associated with sperm chromatin damage may be related to sperm protamination and to serum DHEA.

  7. Expression and secretion of plasma membrane Ca2+-ATPase 4a (PMCA4a) during murine estrus: association with oviductal exosomes and uptake in sperm.

    PubMed

    Al-Dossary, Amal A; Strehler, Emanuel E; Martin-Deleon, Patricia A

    2013-01-01

    PMCA4, a membrane protein, is the major Ca(2+) efflux pump in murine sperm where its deletion leads to a severe loss of hyperactivated motility and to male infertility. We have previously shown that the PMCA4b splice variant interacts with CASK (Ca(2+/)CaM-dependent serine kinase) in regulating sperm Ca(2+). More recently we detected that PMCA4a isoform, in addition to its presence in testis, is secreted in the epididymal luminal fluid and transferred to sperm. Here we show that Pmca4 mRNA is expressed in both the 4a and 4b variants in the vagina, uterus, and oviduct. Immunofluorescence reveals that PMCA4a is similarly expressed and is elevated during estrus, appearing in the glandular and luminal epithelia. Western analysis detected PMCA4a in all tissues and in the luminal fluids (LF) of the vagina (VLF), uterus (ULF), and the oviduct (OLF) collected during estrus. It was ~9- and 4-fold higher in OLF than in VLF and ULF, and only marginally present in LF collected at metestrus/diestrus. Fractionation of the LF collected at estrus, via ultracentrifugation, revealed that 100% of the PMCA4a resides in the vesicular fraction of the ULF and OLF. Transmission electron microscopy (TEM) revealed that OLF vesicles have an exosomal orientation (with the cytoplasmic-side inward), a size range of 25-100 nm, with the characteristic CD9 biomarker. Thus, we dubbed these vesicles "oviductosomes", to which PMCA4a was immunolocalized. Incubation of caudal sperm in the combined LF or exosomes resulted in up to a ~3-fold increase of sperm PMCA4a, as detected by flow cytometry, indicating in vitro uptake. Our results are consistent with the increased requirement of Ca(2+) efflux in the oviduct. They show for the first time the presence of oviductal exosomes and highlight their role, along with uterosomes and vaginal exosomes, in post-testicular sperm acquisition of PMCA4a which is essential for hyperactivated motility and fertility. PMID:24244642

  8. Unraveling the Sperm Bauplan: Relationships Between Sperm Head Morphology and Sperm Function in Rodents.

    PubMed

    Varea-Sánchez, María; Tourmente, Maximiliano; Bastir, Markus; Roldan, Eduardo R S

    2016-07-01

    Rodents have spermatozoa with features not seen in other species. Sperm heads in many rodent species bear one or more apical extensions known as "hooks." The process by which hooks have evolved, together with their adaptive significance, are still controversial issues. In order to improve our understanding of the biological meaning of these sperm head adaptations, we analyzed hook curvature angles, hook length, and overall hook shape in muroid rodents by using geometric morphometrics. We also searched for relationships between hook design and measurements of intermale competition to assess whether postcopulatory sexual selection was an important selective force driving changes in this sperm structure. Finally, we sought possible links between aspects of sperm hook design and sperm velocity as a measure of sperm performance. Results showed that one hook curvature angle is under strong selective pressure. Similarly, hook length appears to be strongly selected by sexual selection, with this selective force also exhibiting a stabilizing role reducing intermale variation in this trait. The adaptive significance of changes in hook structure was supported by the finding that there are strong and significant covariations between hook dimensions and shape and between hook design and sperm swimming velocity. Overall, this study strongly suggests that postcopulatory sexual selection has an important effect on the design of the sperm head that, in turn, is important for enhancing sperm velocity, a function crucial to reaching the vicinity of the female gamete and winning fertilizations under competitive situations. PMID:27281707

  9. Mammalian freeze-dried sperm can maintain their calcium oscillation-inducing ability when microinjected into mouse eggs.

    PubMed

    Liu, Qi-Cai; Chen, Tian-e; Huang, Xiu-Ying; Sun, Fang-Zhen

    2005-03-25

    Mammalian freeze-dried sperm can maintain their genetic integrity and event support full development to term when microinjected into mature oocytes. However, it is unknown whether freeze-dried sperm can still maintain their calcium oscillation-inducing capability. Here, we microinjected mouse and bovine freeze-dried sperm into mouse MII oocytes and examined their calcium oscillation-inducing ability following intracytoplasmic sperm injection (ICSI). Two pieces of information are revealed. First, nearly all oocytes injected with a freeze-dried mouse sperm head or a bovine sperm showed fertilization-like calcium oscillations, indicating that freeze-drying treatment does not affect the activity of the sperm factor responsible for calcium oscillations. Second, freeze-dried sperm exhibited high resistance to external temperature increase. This is shown by the finding that the freeze-dried sperm can maintain their calcium oscillation-inducing capacity even following exposure to 100 degrees C for 3 h. We therefore conclude that mammalian sperm can maintain their calcium oscillation-inducing capability following freeze-drying, rehydration, and ICSI treatments.

  10. Effect of Akti-2 on sperm motility, capacitation and acrosome reaction in a mouse model

    PubMed Central

    QUAN, YANMEI; LIU, QIANG

    2016-01-01

    The aim of the present study was to investigate the effect of the Akt inhibitor, Akti-2, on the sperm motility and acrosome reaction in mice. Mature sperms from the adult mice, aged 8 weeks, were co-incubated with Akti-2 for ~30 min at 37°C in 5% CO2, and the sperm viability was assessed by eosin-nigrosin staining. The sperm total and progressive motility were analyzed by computer-aided sperm analysis. In addition, the acrosome reaction of sperms was detected by the acid phosphatase assay, Coomassie Brilliant Blue staining and fluorescein-isothiocyanate conjugated pisum sativum lectin staining, respectively. Compared with the control (dimethyl sulfoxide), Akti-2 had no effect on sperm viability, but it suppressed the total and progressive motility significantly. Furthermore, the capacitation-associated protein tyrosine phosphorylation and the acrosome reaction induced by calcium ionophore A23187 could be suppressed by Akti-2. These experiments confirmed that Akti-2 significantly impaired the sperm functions, including motility, capacitation and acrosome reaction, and provide the proof for its potential in male reproductive toxicity. PMID:27123250

  11. Giant panda (Ailuropoda melanoleuca) sperm morphometry and function after repeated freezing and thawing.

    PubMed

    Santiago-Moreno, J; Esteso, M C; Pradiee, J; Castaño, C; Toledano-Díaz, A; O'Brien, E; Lopez-Sebastián, A; Martínez-Nevado, E; Delclaux, M; Fernández-Morán, J; Zhihe, Z

    2016-05-01

    This work examines the effects of subsequent cycles of freezing-thawing on giant panda (Ailuropoda melanoleuca) sperm morphometry and function, and assesses whether density-gradient centrifugation (DGC) can increase the number of freezing-thawing cycles this sperm can withstand. A sperm sample was collected by electroejaculation from a mature giant panda and subjected to five freezing-thawing cycles. Although repeated freezing-thawing negatively affected (P < 0.05) sperm motility and membrane integrity, in both nonselected and DCG-selected sperm samples, >60% of the sperm cells in both treatments showed acrosome integrity even after the fifth freezing cycle. In fresh semen, the sperm head length was 4.7 μm, the head width 3.6 μm, area 14.3 μm(2) and perimeter length 14.1 μm. The present results suggest that giant panda sperm trends to be resistant to repeated freezing-thawing, even without DGC selection.

  12. Giant panda (Ailuropoda melanoleuca) sperm morphometry and function after repeated freezing and thawing.

    PubMed

    Santiago-Moreno, J; Esteso, M C; Pradiee, J; Castaño, C; Toledano-Díaz, A; O'Brien, E; Lopez-Sebastián, A; Martínez-Nevado, E; Delclaux, M; Fernández-Morán, J; Zhihe, Z

    2016-05-01

    This work examines the effects of subsequent cycles of freezing-thawing on giant panda (Ailuropoda melanoleuca) sperm morphometry and function, and assesses whether density-gradient centrifugation (DGC) can increase the number of freezing-thawing cycles this sperm can withstand. A sperm sample was collected by electroejaculation from a mature giant panda and subjected to five freezing-thawing cycles. Although repeated freezing-thawing negatively affected (P < 0.05) sperm motility and membrane integrity, in both nonselected and DCG-selected sperm samples, >60% of the sperm cells in both treatments showed acrosome integrity even after the fifth freezing cycle. In fresh semen, the sperm head length was 4.7 μm, the head width 3.6 μm, area 14.3 μm(2) and perimeter length 14.1 μm. The present results suggest that giant panda sperm trends to be resistant to repeated freezing-thawing, even without DGC selection. PMID:26268795

  13. Conspecific sperm precedence in Drosophila.

    PubMed

    Price, C S

    1997-08-14

    Traits that influence the interactions between males and females can evolve very rapidly through sexual selection or sexually antagonistic coevolution. Rapid change in the fertilization systems of independent populations can give rise to reproductive incompatibilities between populations, and may contribute to speciation. Here I provide evidence for cryptic reproductive divergence among three sibling species of Drosophila that leads to a form of postmating isolation. When a female mates with both a conspecific and a heterospecific male, the conspecific sperm fertilize the vast majority of the eggs, regardless of the order of the matings. Heterospecific sperm fertilize fewer eggs after these double matings than after single matings. Experiments using spermless males show that the seminal fluid of the conspecific male is largely responsible for this conspecific sperm precedence. Moreover, when two males of the same species mate sequentially with a female from a different species, a highly variable pattern of sperm precedence replaces the second-male sperm precedence that is consistently found within species. These results indicate that females mediate sperm competition, and that second-male sperm precedence is not an automatic consequence of the mechanics of sperm storage.

  14. Sperm motion analysis

    NASA Astrophysics Data System (ADS)

    Salari, Valiollah

    1991-07-01

    This paper presents a computerized technique for quantitative analysis of the movement characteristics of spermatozoa. Stored video images of spermatozoa are digitized at a fixed time interval. The digital images are stored as a sequence of frames in a microcomputer. The analysis of the sequence comprises two main tasks: finding the location of the centroid for each sperm and tracking them over the entire sequences. Information from the motion of each moving cell will be used for tracking. Experimental results are presented to show the merits of the proposed algorithm for tracking.

  15. Sperm Morphology Assessment in Captive Neotropical Primates.

    PubMed

    Swanson, W F; Valle, R R; Carvalho, F M; Arakaki, P R; Rodas-Martínez, A Z; Muniz, Japc; García-Herreros, M

    2016-08-01

    The main objective of this study was to evaluate sperm morphology in four neotropical primate species to compare the sperm morphological traits and the sperm morphometric parameters as a basis for establishing normative sperm standards for each species. Data from 80 ejaculates collected from four primate species, Callithrix jacchus, Callimico goeldii, Alouatta caraya and Ateles geoffroyi, were analysed for detection of sperm morphological alterations using subjective World Health Organization (WHO-2010) standards and Sperm Deformity Index (SDI) criteria, objective computer-assisted sperm morphometry analysis (CASMA) and subpopulation sperm determination (SSD) methods. There were multiple differences (p < 0.01) observed among primate species in values obtained from WHO-2010, SDI, CASMA and SSD sperm analysis methods. In addition, multiple significant positive and negative correlations were observed between the sperm morphological traits (SDI, Sperm Deformity Index Head Defects, Sperm Deformity Index Midpiece Defects, Sperm Deformity Index Tail Defects, Normal Sperm, Head Defects, Midpiece Defects and Tail Defects) and the sperm morphometric parameters (SSD, Area (A), Perimeter (P), Length (L), Width (W), Ellipticity, Elongation and Rugosity) (p ≤ 0.046). In conclusion, our findings using different evaluation methods indicate that pronounced sperm morphological variation exists among these four neotropical primate species. Because of the strong relationship observed among morphological and morphometric parameters, these results suggest that application of objective analysis methods could substantially improve the reliability of comparative studies and help to establish valid normative sperm values for neotropical primates. PMID:27260333

  16. Sperm Morphology Assessment in Captive Neotropical Primates.

    PubMed

    Swanson, W F; Valle, R R; Carvalho, F M; Arakaki, P R; Rodas-Martínez, A Z; Muniz, Japc; García-Herreros, M

    2016-08-01

    The main objective of this study was to evaluate sperm morphology in four neotropical primate species to compare the sperm morphological traits and the sperm morphometric parameters as a basis for establishing normative sperm standards for each species. Data from 80 ejaculates collected from four primate species, Callithrix jacchus, Callimico goeldii, Alouatta caraya and Ateles geoffroyi, were analysed for detection of sperm morphological alterations using subjective World Health Organization (WHO-2010) standards and Sperm Deformity Index (SDI) criteria, objective computer-assisted sperm morphometry analysis (CASMA) and subpopulation sperm determination (SSD) methods. There were multiple differences (p < 0.01) observed among primate species in values obtained from WHO-2010, SDI, CASMA and SSD sperm analysis methods. In addition, multiple significant positive and negative correlations were observed between the sperm morphological traits (SDI, Sperm Deformity Index Head Defects, Sperm Deformity Index Midpiece Defects, Sperm Deformity Index Tail Defects, Normal Sperm, Head Defects, Midpiece Defects and Tail Defects) and the sperm morphometric parameters (SSD, Area (A), Perimeter (P), Length (L), Width (W), Ellipticity, Elongation and Rugosity) (p ≤ 0.046). In conclusion, our findings using different evaluation methods indicate that pronounced sperm morphological variation exists among these four neotropical primate species. Because of the strong relationship observed among morphological and morphometric parameters, these results suggest that application of objective analysis methods could substantially improve the reliability of comparative studies and help to establish valid normative sperm values for neotropical primates.

  17. Ion channels, phosphorylation and mammalian sperm capacitation.

    PubMed

    Visconti, Pablo E; Krapf, Dario; de la Vega-Beltrán, José Luis; Acevedo, Juan José; Darszon, Alberto

    2011-05-01

    Sexually reproducing animals require an orchestrated communication between spermatozoa and the egg to generate a new individual. Capacitation, a maturational complex phenomenon that occurs in the female reproductive tract, renders spermatozoa capable of binding and fusing with the oocyte, and it is a requirement for mammalian fertilization. Capacitation encompasses plasma membrane reorganization, ion permeability regulation, cholesterol loss and changes in the phosphorylation state of many proteins. Novel tools to study sperm ion channels, image intracellular ionic changes and proteins with better spatial and temporal resolution, are unraveling how modifications in sperm ion transport and phosphorylation states lead to capacitation. Recent evidence indicates that two parallel pathways regulate phosphorylation events leading to capacitation, one of them requiring activation of protein kinase A and the second one involving inactivation of ser/thr phosphatases. This review examines the involvement of ion transporters and phosphorylation signaling processes needed for spermatozoa to achieve capacitation. Understanding the molecular mechanisms leading to fertilization is central for societies to deal with rising male infertility rates, to develop safe male gamete-based contraceptives and to preserve biodiversity through better assisted fertilization strategies.

  18. Ion channels, phosphorylation and mammalian sperm capacitation

    PubMed Central

    Visconti, Pablo E; Krapf, Dario; de la Vega-Beltrán, José Luis; Acevedo, Juan José; Darszon, Alberto

    2011-01-01

    Sexually reproducing animals require an orchestrated communication between spermatozoa and the egg to generate a new individual. Capacitation, a maturational complex phenomenon that occurs in the female reproductive tract, renders spermatozoa capable of binding and fusing with the oocyte, and it is a requirement for mammalian fertilization. Capacitation encompasses plasma membrane reorganization, ion permeability regulation, cholesterol loss and changes in the phosphorylation state of many proteins. Novel tools to study sperm ion channels, image intracellular ionic changes and proteins with better spatial and temporal resolution, are unraveling how modifications in sperm ion transport and phosphorylation states lead to capacitation. Recent evidence indicates that two parallel pathways regulate phosphorylation events leading to capacitation, one of them requiring activation of protein kinase A and the second one involving inactivation of ser/thr phosphatases. This review examines the involvement of ion transporters and phosphorylation signaling processes needed for spermatozoa to achieve capacitation. Understanding the molecular mechanisms leading to fertilization is central for societies to deal with rising male infertility rates, to develop safe male gamete-based contraceptives and to preserve biodiversity through better assisted fertilization strategies. PMID:21540868

  19. Paternal poly (ADP-ribose) metabolism modulates retention of inheritable sperm histones and early embryonic gene expression.

    PubMed

    Ihara, Motomasa; Meyer-Ficca, Mirella L; Leu, N Adrian; Rao, Shilpa; Li, Fan; Gregory, Brian D; Zalenskaya, Irina A; Schultz, Richard M; Meyer, Ralph G

    2014-05-01

    To achieve the extreme nuclear condensation necessary for sperm function, most histones are replaced with protamines during spermiogenesis in mammals. Mature sperm retain only a small fraction of nucleosomes, which are, in part, enriched on gene regulatory sequences, and recent findings suggest that these retained histones provide epigenetic information that regulates expression of a subset of genes involved in embryo development after fertilization. We addressed this tantalizing hypothesis by analyzing two mouse models exhibiting abnormal histone positioning in mature sperm due to impaired poly(ADP-ribose) (PAR) metabolism during spermiogenesis and identified altered sperm histone retention in specific gene loci genome-wide using MNase digestion-based enrichment of mononucleosomal DNA. We then set out to determine the extent to which expression of these genes was altered in embryos generated with these sperm. For control sperm, most genes showed some degree of histone association, unexpectedly suggesting that histone retention in sperm genes is not an all-or-none phenomenon and that a small number of histones may remain associated with genes throughout the genome. The amount of retained histones, however, was altered in many loci when PAR metabolism was impaired. To ascertain whether sperm histone association and embryonic gene expression are linked, the transcriptome of individual 2-cell embryos derived from such sperm was determined using microarrays and RNA sequencing. Strikingly, a moderate but statistically significant portion of the genes that were differentially expressed in these embryos also showed different histone retention in the corresponding gene loci in sperm of their fathers. These findings provide new evidence for the existence of a linkage between sperm histone retention and gene expression in the embryo.

  20. Understanding fertilization through intracytoplasmic sperm injection (ICSI)

    PubMed Central

    Neri, Queenie V.; Lee, Bora; Rosenwaks, Zev; Machaca, Khaled; Palermo, Gianpiero D.

    2014-01-01

    Summary Since the establishment of in vitro fertilization, it became evident that almost half of the couples failed to achieve fertilization and this phenomenon was attributed to a male gamete dysfunction. The adoption of assisted fertilization techniques particularly ICSI has been able to alleviate male factor infertility by granting the consistent ability of a viable spermatozoon to activate an oocyte. Single sperm injection, by pinpointing the beginning of fertilization, has been an invaluable tool in clarifying the different aspects of early fertilization and syngamy. However, even with ICSI some couples fail to fertilize due to ooplasmic dysmaturity in relation to the achieved nuclear maturation marked by the extrusion of the first polar body. More uncommon are cases where the spermatozoa partially or completely lack the specific oocyte activating factor. In this work, we review the most relevant aspects of fertilization and its failure through assisted reproductive technologies. Attempts at diagnosing and treating clinical fertilization failure are described. PMID:24290744

  1. Understanding fertilization through intracytoplasmic sperm injection (ICSI).

    PubMed

    Neri, Queenie V; Lee, Bora; Rosenwaks, Zev; Machaca, Khaled; Palermo, Gianpiero D

    2014-01-01

    Since the establishment of in vitro fertilization, it became evident that almost half of the couples failed to achieve fertilization and this phenomenon was attributed to a male gamete dysfunction. The adoption of assisted fertilization techniques particularly ICSI has been able to alleviate male factor infertility by granting the consistent ability of a viable spermatozoon to activate an oocyte. Single sperm injection, by pinpointing the beginning of fertilization, has been an invaluable tool in clarifying the different aspects of early fertilization and syngamy. However, even with ICSI some couples fail to fertilize due to ooplasmic dysmaturity in relation to the achieved nuclear maturation marked by the extrusion of the first polar body. More uncommon are cases where the spermatozoa partially or completely lack the specific oocyte activating factor. In this work, we review the most relevant aspects of fertilization and its failure through assisted reproductive technologies. Attempts at diagnosing and treating clinical fertilization failure are described.

  2. Robotic ICSI (intracytoplasmic sperm injection).

    PubMed

    Lu, Zhe; Zhang, Xuping; Leung, Clement; Esfandiari, Navid; Casper, Robert F; Sun, Yu

    2011-07-01

    This paper is the first report of robotic intracytoplasmic sperm injection (ICSI). ICSI is a clinical procedure performed worldwide in fertility clinics, requiring pick-up of a single sperm and insertion of it into an oocyte (i.e., egg cell). Since its invention 20 years ago, ICSI has been conducted manually by a handful of highly skilled embryologists; however, success rates vary significantly among clinics due to poor reproducibility and inconsistency across operators. We leverage our work in robotic cell injection to realize robotic ICSI and aim ultimately, to standardize how clinical ICSI is performed. This paper presents some of the technical aspects of our robotic ICSI system, including a cell holding device, motion control, and computer vision algorithms. The system performs visual tracking of single sperm, robotic immobilization of sperm, aspiration of sperm with picoliter volume, and insertion of sperm into an oocyte with a high degree of reproducibility. The system requires minimal human involvement (requiring only a few computer mouse clicks), and is human operator skill independent. Using the hamster oocyte-human sperm model in preliminary trials, the robotic system demonstrated a high success rate of 90.0% and survival rate of 90.7% (n=120). PMID:21521663

  3. Comparative sperm ultrastructure in Nemertea.

    PubMed

    von Döhren, J; Beckers, P; Vogeler, R; Bartolomaeus, T

    2010-07-01

    Although the monophyly of Nemertea is strongly supported by unique morphological characters and results of molecular phylogenetic studies, their ingroup relationships are largely unresolved. To contribute solving this problem we studied sperm ultrastructure of 12 nemertean species that belong to different subtaxa representing the commonly recognized major monophyletic groups. The study yielded a set of 26 characters with an unexpected variation among species of the same genus (Tubulanus and Procephalothrix species), whereas other species varied in metric values or only one character state (Ramphogordius). In some species, the sperm nucleus has grooves (Zygonemertes virescens, Amphiporus imparispinosus) that may be twisted and give a spiral shape to the sperm head (Paranemertes peregrina, Emplectonema gracile). To make the characters from sperm ultrastructure accessible for further phylogenetic analyses, they were coded in a character matrix. Published data for eight species turned out to be sufficiently detailed to be included. Comparative evaluation of available information on the sperm ultrastructure suggests that subtaxa of Heteronemertea and Hoplonemertea are supported as monophyletic by sperm morphology. However, the data do not provide information on the existing contradictions regarding the internal relationships of "Palaeonemertea." Nevertheless, our study provides evidence that sperm ultrastructure yields numerous potentially informative characters that will be included in upcoming phylogenetic analyses.

  4. Chromosomal abnormalities in human sperm

    SciTech Connect

    Martin, R.H.

    1985-01-01

    The ability to analyze human sperm chromosome complements after penetration of zona pellucida-free hamster eggs provides the first opportunity to study the frequency and type of chromosomal abnormalities in human gametes. Two large-scale studies have provided information on normal men. We have studied 1,426 sperm complements from 45 normal men and found an abnormality rate of 8.9%. Brandriff et al. (5) found 8.1% abnormal complements in 909 sperm from 4 men. The distribution of numerical and structural abnormalities was markedly dissimilar in the 2 studies. The frequency of aneuploidy was 5% in our sample and only 1.6% in Brandriff's, perhaps reflecting individual variability among donors. The frequency of 24,YY sperm was low: 0/1,426 and 1/909. This suggests that the estimates of nondisjunction based on fluorescent Y body data (1% to 5%) are not accurate. We have also studied men at increased risk of sperm chromosomal abnormalities. The frequency of chromosomally unbalanced sperm in 6 men heterozygous for structural abnormalities varied dramatically: 77% for t11;22, 32% for t6;14, 19% for t5;18, 13% for t14;21, and 0% for inv 3 and 7. We have also studied 13 cancer patients before and after radiotherapy and demonstrated a significant dose-dependent increase of sperm chromosome abnormalities (numerical and structural) 36 months after radiation treatment.

  5. Robotic ICSI (intracytoplasmic sperm injection).

    PubMed

    Lu, Zhe; Zhang, Xuping; Leung, Clement; Esfandiari, Navid; Casper, Robert F; Sun, Yu

    2011-07-01

    This paper is the first report of robotic intracytoplasmic sperm injection (ICSI). ICSI is a clinical procedure performed worldwide in fertility clinics, requiring pick-up of a single sperm and insertion of it into an oocyte (i.e., egg cell). Since its invention 20 years ago, ICSI has been conducted manually by a handful of highly skilled embryologists; however, success rates vary significantly among clinics due to poor reproducibility and inconsistency across operators. We leverage our work in robotic cell injection to realize robotic ICSI and aim ultimately, to standardize how clinical ICSI is performed. This paper presents some of the technical aspects of our robotic ICSI system, including a cell holding device, motion control, and computer vision algorithms. The system performs visual tracking of single sperm, robotic immobilization of sperm, aspiration of sperm with picoliter volume, and insertion of sperm into an oocyte with a high degree of reproducibility. The system requires minimal human involvement (requiring only a few computer mouse clicks), and is human operator skill independent. Using the hamster oocyte-human sperm model in preliminary trials, the robotic system demonstrated a high success rate of 90.0% and survival rate of 90.7% (n=120).

  6. Sperm ubiquitination in epididymal feline semen.

    PubMed

    Vernocchi, Valentina; Morselli, Maria Giorgia; Varesi, Sara; Nonnis, Simona; Maffioli, Elisa; Negri, Armando; Tedeschi, Gabriella; Luvoni, Gaia Cecilia

    2014-09-01

    Ubiquitin is a 8.5-kDa peptide that tags other proteins for proteasomal degradation. It has been proposed that ubiquitination might be responsible for the elimination of defective spermatozoa during transit through the epididymis in humans and cattle, but its exact biological function in seminal plasma has not yet been clarified. In the domestic cat (Felis catus), the percentage of immature, unviable, and abnormal spermatozoa decreases during the epididymal transit, indicating the existence of a mechanism that removes defective spermatozoa. Magnetic cell separation techniques, based on the use of magnetic beads coated with anti-ubiquitin antibodies, may allow the selective capture of ubiquitinated spermatozoa from semen, thus contributing to the identification of a potential correlation between semen quality and ubiquitination process. Moreover, the selective identification of all the ubiquitinated proteins in different epididymal regions could give a better understanding of the ubiquitin role in feline sperm maturation. The aims of this study were as follows: (1) to verify the possibility of separating ubiquitinated spermatozoa with magnetic ubiquitin beads and identify the morphological and acrosomal differences between whole sample and unbound gametes, (2) to characterize all the ubiquitinated proteins in spermatozoa retrieved in the three epididymal regions by a proteomic approach. The data indicated the presence of ubiquitinated proteins in cat epididymal semen. However, a correlation between abnormal and ubiquitinated spermatozoa has not been found, and ubiquitin cannot be considered as a biomarker of quality of epididymal feline spermatozoa. To the author's knowledge, this is the first identification of all the ubiquitinated proteins of cat spermatozoa collected from different epididymal regions. The proteomic pattern allows a further characterization of cat epididymal semen and represents a contribute to a better understanding of the ubiquitin role in

  7. GLUTATHIONE (GSH) CONCENTRATIONS VARY WITH THE CELL CYCLE IN MATURING HAMSTER OOCYTES, ZYGOTES AND PRE-IMPLANATION EMBRYOS

    EPA Science Inventory

    Abstract
    Glutathione (GSH) is thought to play critical roles in oocyte function including spindle maintenance and provision of reducing power needed to initiate sperm chromatin decondensation. Previous observations that GSH concentrations are higher in mature than immature o...

  8. Market maturity

    SciTech Connect

    Meade, B.; Bowden, S.; Ellis, M

    1995-02-01

    The power sector in the Philipines provides one of the most mature independent power markets in Asia. Over the past five years, National Power Corp. (NPC), the government owned utility, has actively invited the power sector into power generation. Distribution has remained in the hands of private and rural cooperative utilities. Private utilities have been operating as full requirements customers of NPC while the growth in capacity additions by independent power producers (IPPs) has outpaced NPC`s for the second year in a row. With a recovering economy and regulatory reform proceeding, the outlook for independent power remains strong through the end of the decade. The Philipine Congress is now reviewing draft legislation that will decentralize NPC and begin the process of privatization and market-based reforms throughout the country`s power sector.

  9. Lectin binding of human sperm associates with DEFB126 mutation and serves as a potential biomarker for subfertility

    PubMed Central

    Xin, Aijie; Cheng, Li; Diao, Hua; Wu, Yancheng; Zhou, Shumin; Shi, Changgen; Sun, Yangyang; Wang, Peng; Duan, Shiwei; Zheng, Jufen; Wu, Bin; Yuan, Yao; Gu, Yihua; Chen, Guowu; Sun, Xiaoxi; Shi, Huijuan; Tao, Shengce; Zhang, Yonglian

    2016-01-01

    Coating on the sperm surface, glycocalyx, plays a key role in sperm motility, maturation and fertilization. A comprehensive profile of sperm surface glycans will greatly facilitate both basic researches and clinical studies. Because of the capability of recognizing different glycan moieties, lectins are widely used in glycobiology. However, lacking high-throughput technology, limited lectins have been reported for analyzing the glycan of human sperm. In this study, we employed a lectin microarray for profiling the surface glycans of human sperm, on which 54 out of 91 lectins showed positive binding. Based on this technique, we compared lectin binding profiling of sperm with homozygous DEFB126 mutation (del/del) with that of wild type (wt/wt). DEFB126 was reported to contribute to the sialylation on sperm surface and its homozygous mutation was related to male subfertility. Six lectins (Jacalin/AIA, GHA, ACL, MPL, VVL and ABA) were found to develop lower binding affinity to sperm with del/del. Further validation showed that these lectins, especially ABA and MPL, can be potential biomarkers for clinical diagnosis of subfertility due to the mutation of DEFB126. Our research provides insight into the detection of some unexplained male subfertility, and the lectin microarray is generally applicable for infertility/subfertility sperm biomarker discovery. PMID:26832966

  10. In vitro decondensation of the sperm chromatin in Holothuria tubulosa (sea cucumber) not affecting proteolysis of basic nuclear proteins.

    PubMed

    del Valle, Luis J

    2005-06-01

    Sea urchin and sea star oocyte extracts contain proteolytic activities that are active against sperm basic nuclear proteins (SNBP). This SNBP degradation has been related to the decondensation of sperm chromatin as a possible model to male pronuclei formation. We have studied the presence of this proteolytic activity in Holothuria tubulosa (sea cucumber) and its possible relationship with sperm nuclei decondensation. The mature oocyte extracts from H. tubulosa contain a proteolytic activity to SNBP located in the macromolecular fraction of the egg-jelly layer. SNBP degradation occurred both on sperm nuclei and on purified SNBP, histones being more easily degraded than protein Ø(o) (sperm-specific protein). SNBP degradation was found to be dependent on concentration, incubation time, presence of Ca(2+), pH, and this activity could be a serine-proteinase. Thermal denaturalization of the oocyte extracts (80 degrees C, 10-15 min) inactivates its proteolytic activity on SNBP but does not affect sperm nuclei decondensation. These results would suggest that sperm nuclei decondensation occurs by a mechanism different from SNBP degradation. Thus, the sperm nuclei decondensation occurs by a thermostable factor(s) and the removal of linker SNBP (H1 and protein Ø(o)) will be a first condition in the process of sperm chromatin remodeling. PMID:16026541

  11. Intracytoplasmic sperm injection.

    PubMed

    Van Steirteghem, André; Devroey, P; Liebaers, I

    2002-01-25

    Intracytoplasmic sperm injection (ICSI) with ejaculated, epididymal or testicular spermatozoa was first successful in 1992 and has since become the widely accepted treatment for couples with severe male-factor infertility. The outcome of several thousands of ICSI cycles in terms of fertilization, embryo cleavage and implantation is similar to that for conventional in-vitro fertilization in couples with tubal or idiopathic infertility. To evaluate the important issue of safety of the new technique of ICSI, a prospective follow-up study of children born after ICSI was carried out. The aim was to compile data on karyotypes, congenital malformations, growth parameters and developmental milestones. Parents' agreement to genetic counseling was obtained, as well as prenatal diagnosis, followed by a physical examination of the children at 2 months, 1 and 2 years. Important outcome data to be examined comprise information on major and minor congenital malformations obtained prenatally or after birth, as well as on the further development of the children.

  12. An ultrastructural study of spermatogenesis and sperm morula breakdown in Arenicola marina (L.) (Annelida: Polychaeta)

    NASA Astrophysics Data System (ADS)

    Pacey, A. A.; Bentley, M. G.

    1992-06-01

    Spermatogenesis in the lugworm Arenicola marina, in common with other members of Arenicolidae, occurs in the coelomic fluid and results in the formation of discs of mature spermatozoa known as a morulae. Within a morula, individual spermatozoa are connected by a common mass of cytoplasm called the cytophore and therefore make up a syncitium. Immediately prior to spawning, and in response to an endocrine substance known as “Sperm Maturation Factor” (SMF), the structure of the sperm morulae breaks down and free spermatozoa are liberated. These are subsequently spawned from the body cavity. The investigation described here uses transmission electron microscopy to investigate the ultrastructural changes, which accompany spermatogenesis and the breakdown of sperm morulae in response to SMF in vitro. The study demonstrates that the cytophore appears to have a key role both during spermatogenesis and during sperm morula breakdown. The ultrastructure of sperm morulae and of mature spermatozoa is described. The structure of spermatozoa is shown to be primitive with a single flagellum which appears to be coiled at its distal end. The phagocytosis of free spermatozoa by coelomocytes is also described and it is suggested that these may play a role in the resorption of unspawned gametes in vivo.

  13. Abnormalities of sperm morphology in cases of persistent infertility after vasectomy reversal.

    PubMed

    Pelfrey, R J; Overstreet, J W; Lewis, E L

    1982-07-01

    Persistent infertility after vasectomy reversal by vasovasostomy may be due to irreversible changes in epididymal physiology, producing morphologic abnormalities of the sperm tail. Specimens from 29 men with persistent infertility following vasectomy reversal were analyzed and sperm motility and morphology were evaluated. the percentage of motile sperm was below normal in 23 specimens. Swimming speed evaluation on 20 specimens showed only 4 were below the normal range. In 19 of the 29 specimens, 10% or more of the sperm cells examined were characterized by a normal head and a coiled or shortened tail. Within this group, the percentage of sperm with tail abnormalities ranged from 2-64%, with a mean of 18.1%. The appearance of sperm tail abnormalities in conjunction with normal or high sperm concentrations suggests a disturbance of epididymal physiology. The epididymal environment is required for the final maturation of spermatazoa and the acquisition of normal motility and fertilizing ability. The study results suggest that these epididymal functions may be impaired in some men after vasectomy. A case report of a 32 year old man who had a vasectomy 7 years prior to referral to the evaluation group, and a successful vasovasostomy 2 years prior, revealed only 20% of the sperm evaluated in the initial specimen had the normal head and tail shape. His semen volume was 3.5 ml with a sperm concentration of 250 million/ml. 25% of the sperm were motile. Reexamination of the semen 8 times during the next year showed no significant changes. The cervical mucus penetration test showed no abnormalities of the sperm-cervical mucus interaction. When the motile sperm were spearated from the immotile cells and incubated with zona-free hamster eggs, all of the eggs were penetrated. Attempts were unsuccessful to isolate sufficient numbers of motile cells for artificial insemination, however, a normal pregnancy was conceived 1 year after the initial evaluation without additional therapy

  14. Quantitative Glycopeptide Changes in Rat Sperm During Epididymal Transit.

    PubMed

    Villaverde, Ana Izabel Silva Balbin; Hetherington, Louise; Baker, Mark A

    2016-04-01

    Mammalian spermatozoa acquire fertilizing potential as they undergo a series of changes during epididymal transit. One major facet of such is the alterations in the sperm glycome. Modifications of the sialic acid content within glycan moieties are known to regulate epitope presentation and cellular adhesion and signaling, all of which may be critical for sperm to successfully reach and fertilize the egg. To date, there is paucity of information regarding the sialic acid changes that occur on spermatozoa during epididymal transit. Therefore, the aim of this study was to identify N-linked sialylated glycoproteins in rat epididymal sperm and investigate whether they are regulated during epididymal transit. Sialylated glycopeptides from caput, corpus, and cauda spermatozoa were enriched using titanium dioxide beads. Bound N-linked glycopeptides were released by enzymatic deglycosylation using PNGase F and then analyzed by liquid chromatography tandem-mass spectrometry. A total of 92 unique N-linked sialylated glycopeptides were identified from 65 different proteins. These included members of the disintegrin and metalloproteinase domain-containing protein family (ADAM), Basigin, and Testis-expressed protein 101 (TEX101). Remarkably, label-free quantification showed that more than half of these peptides (48/92) were regulated during epididymal transit. Of interest, the protein TEX101 exhibited PNGase F-resistant deglycosylation under the conditions used in this study. The results from this study showed that changes in the N-linked sialoglycoprotein profile is a major hallmark of sperm maturation in rats.

  15. The localization of protein carboxyl-methylase in sperm tails

    PubMed Central

    1980-01-01

    Protein carboxyl-methylase (PCM), an enzyme known to be involved in exocytotic secretion and chemotaxis, has been studied in rat and rabbit spermatozoa. PCM activity and its substrate methyl acceptor protein(s) (MAP) were demonstrated in the supernate after solubilization of the sperm cell membrane by detergent (Triton X-100). A protein methylesterase that hydrolyzes methyl ester bonds created by PCM was demonstrated in rabbit but not in rat spermatozoa. This enzyme was not solubilized by nonionic detergent. The specific activities of PCM in rat spermatozoa from caput and cauda epididymis were similar and lower than that found in testis. By contrast, MAP substrates were low in testis and increased in parallel with sperm maturation in the epididymis. Multiple MAP were demonstrated in spermatozoa by polyacrylamide gel electrophoresis. The pattern of these proteins was similar in spermatozoa from different portions of the reproductive tract. Fractionation of heads and tails of rat spermatozoa on sucrose gradients indicated that PCM was found exclusively in the tail fraction, whereas MAP was detected both in head and tail fractions. The presence of all the components of the protein carboxyl-methylation system in spermatozoa and the localization of PCM and some of its substrates in the sperm tail are consistent with their involvement in sperm cell motility. PMID:7400214

  16. A comparative analysis of the morphology and evolution of permanent sperm depletion in spiders.

    PubMed

    Michalik, Peter; Rittschof, Clare C

    2011-01-11

    Once thought to be energetically cheap and easy to produce, empirical work has shown that sperm is a costly and limited resource for males. In some spider species, there is behavioral evidence that sperm are permanently depleted after a single mating. This extreme degree of mating investment appears to co-occur with other reproductive strategies common to spiders, e.g. genital mutilation and sexual cannibalism. Here we corroborate that sperm depletion in the golden orb-web spider Nephila clavipes is permanent by uncovering its mechanistic basis using light and electron microscopy. In addition, we use a phylogeny-based statistical analysis to test the evolutionary relationships between permanent sperm depletion (PSD) and other reproductive strategies in spiders. Male testes do not produce sperm during adulthood, which is unusual in spiders. Instead, spermatogenesis is nearly synchronous and ends before the maturation molt. Testis size decreases as males approach their maturation molt and reaches its lowest point after sperm is transferred into the male copulatory organs (pedipalps). As a consequence, the amount of sperm available to males for mating is limited to the sperm contained in the pedipalps, and once it is used, males lose their ability to fertilize eggs. Our data suggest that PSD has evolved independently at least three times within web-building spiders and is significantly correlated with the evolution of other mating strategies that limit males to monogamy, including genital mutilation and sexual cannibalism. We conclude that PSD may be an energy-saving adaptation in species where males are limited to monogamy. This could be particularly important in web-building spiders where extreme sexual size dimorphism results in large, sedentary females and small, searching males who rarely feed as adults and are vulnerable to starvation. Future work will explore possible energetic benefits and the evolutionary lability of PSD relative to other mate

  17. MORPHOLOGY OF GAMETE MEMBRANE FUSION AND OF SPERM ENTRY INTO OOCYTES OF THE SEA URCHIN

    PubMed Central

    Franklin, Luther E.

    1965-01-01

    Sea urchin gametes predominate in molecular studies of fertilization, yet relatively little is known of the subcellular aspects of sperm entry in this group. Accordingly, it seemed desirable to make a detailed examination of sperm entry phenomena in sea urchins with the electron microscope. Gametes of the sea urchins Arbacia punctulata and Lytechinus variegatus were used in this study. Samples of eggs containing 2 to 8 per cent oocytes were selected and fixed with osmium tetroxide in sea water at various intervals after insemination. Fixed specimens were embedded in Epon 812, sectioned, and examined with an electron microscope. An apical vesicle was observed at the anterior end of the acrosome. The presence of this structure, together with other observations, suggested that initiation of the acrosome reaction in sea urchin sperm involves dehiscence of the acrosomal region with the subsequent release of the acrosomal granule. Contact and initial fusion of gamete membranes was observed in mature eggs and oocytes and invariably involved the extended acrosomal tubule of the spermatozoon. Only one spermatozoon normally enters the mature egg. The probability of locating such a sperm in ultrathin sections is exceedingly low. Several sperm do normally enter oocytes. Consequently, observations of sperm entry were primarily restricted to the latter. The manner of sperm entry into oocytes did not resemble phagocytosis. Organelles of the spermatozoon were progressively divested of their plasma membrane as they entered the ground cytoplasm of the oocyte fertilization cone. Initiation of the acrosome reaction, contact and initial fusion of gamete membranes, and sperm entry into oocytes of sea urchins conform to the Hydroides-Saccoglossus pattern of early fertilization events as described by Colwin and Colwin (13). PMID:19866669

  18. Bisphenol A accelerates capacitation-associated protein tyrosine phosphorylation of rat sperm by activating protein kinase A.

    PubMed

    Wan, Xiaofeng; Ru, Yanfei; Chu, Chen; Ni, Zimei; Zhou, Yuchuan; Wang, Shoulin; Zhou, Zuomin; Zhang, Yonglian

    2016-06-01

    Bisphenol A (BPA) is a synthetic estrogen-mimic chemical. It has been shown to affect many reproductive endpoints. However, the effect of BPA on the mature sperm and the mechanism of its action are not clear yet. Here, our in vitro studies indicated that BPA could accelerate sperm capacitation-associated protein tyrosine phosphorylation in time- and dose-dependent manners. In vivo, the adult male rats exposed to a high dose of BPA could result in a significant increase in sperm activity. Further investigation demonstrated that BPA could accelerate capacitation-associated protein tyrosine phosphorylation even if sperm were incubated in medium devoid of BSA, HCO3 (-), and Ca(2+) However, this action of BPA stimulation could be blocked by H89, a highly selective blocker of protein kinase A (PKA), but not by KH7, a specific inhibitor of adenylyl cyclase. These data suggest that BPA may activate PKA to affect sperm functions and male fertility. PMID:27174873

  19. Successful pregnancy achieved by intracytoplasmic sperm injection using cryopreserved electroejaculate sperm in a couple both with spinal cord injury: a case report.

    PubMed

    Chen, Shee-Uan; Shieh, Jen-Yi; Wang, Yen-Ho; Lu, Thomas; Ho, Hong-Nerng; Yang, Yu-Shih

    2005-09-01

    Anejaculation and poor semen quality are 2 major causes of infertility in men with spinal cord injury (SCI). The low motility of retrieved sperm often results in use of intracytoplasmic sperm injection (ICSI) to achieve fertilization. Pregnancy is a challenging event for women with SCI. Herein we report a pregnancy after ICSI with cryopreserved electroejaculate sperm for a couple both with SCI. The husband had T10 paraplegia with a neurogenic bladder. He underwent 2 electroejaculations. The concentration of sperm was 0.1 x 10(6)/mL to 0.3 x 10(6)/mL, with a motility of 5% to 20%. ICSI was considered the best choice for the couple. His wife had L2 paraplegia with cauda equina syndrome. She underwent controlled ovarian hyperstimulation, and 10 oocytes were retrieved. Eight mature oocytes were injected using thawed sperm, which resulted in 5 normal zygotes. Conception was achieved by the transfer of 4 embryos into the uterus. A healthy female baby was delivered vaginally at 39 weeks of gestation. This woman had never undergone any other assisted reproductive technology (ART) procedures. With the advancement of ART and prenatal care, this couple achieved a successful pregnancy. The use of cryopreserved electroejaculated sperm for ICSI can avoid the inconvenience or cost to the patient of repeated electroejaculations.

  20. Sperm competition: linking form to function

    PubMed Central

    2008-01-01

    Background Using information from physics, biomechanics and evolutionary biology, we explore the implications of physical constraints on sperm performance, and review empirical evidence for links between sperm length and sperm competition (where two or more males compete to fertilise a female's eggs). A common theme in the literature on sperm competition is that selection for increased sperm performance in polyandrous species will favour the evolution of longer, and therefore faster swimming, sperm. This argument is based on the common assumption that sperm swimming velocity is directly related to sperm length, due to the increased thrust produced by longer flagella. Results We critically evaluate the evidence for links between sperm morphology and swimming speed, and draw on cross-disciplinary studies to show that the assumption that velocity is directly related to sperm length will rarely be satisfied in the microscopic world in which sperm operate. Conclusion We show that increased sperm length is unlikely to be driven by selection for increased swimming speed, and that the relative lengths of a sperm's constituent parts, rather than their absolute lengths, are likely to be the target of selection. All else being equal, we suggest that a simple measure of the ratio of head to tail length should be used to assess the possible link between morphology and speed. However, this is most likely to be the case for external fertilizers in which females have relatively limited opportunity to influence a sperm's motility. PMID:19032741

  1. 21 CFR 173.275 - Hydrogenated sperm oil.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... conditions: (a) The sperm oil is derived from rendering the fatty tissue of the sperm whale or is prepared by synthesis of fatty acids and fatty alcohols derived from the sperm whale. The sperm oil obtained...

  2. 21 CFR 173.275 - Hydrogenated sperm oil.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... conditions: (a) The sperm oil is derived from rendering the fatty tissue of the sperm whale or is prepared by synthesis of fatty acids and fatty alcohols derived from the sperm whale. The sperm oil obtained...

  3. 21 CFR 173.275 - Hydrogenated sperm oil.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... conditions: (a) The sperm oil is derived from rendering the fatty tissue of the sperm whale or is prepared by synthesis of fatty acids and fatty alcohols derived from the sperm whale. The sperm oil obtained...

  4. Targeted inactivation of the mouse epididymal beta-defensin 41 alters sperm flagellar beat pattern and zona pellucida binding.

    PubMed

    Björkgren, Ida; Alvarez, Luis; Blank, Nelli; Balbach, Melanie; Turunen, Heikki; Laajala, Teemu Daniel; Toivanen, Jussi; Krutskikh, Anton; Wahlberg, Niklas; Huhtaniemi, Ilpo; Poutanen, Matti; Wachten, Dagmar; Sipilä, Petra

    2016-05-15

    During epididymal maturation, sperm acquire the ability to swim progressively by interacting with proteins secreted by the epididymal epithelium. Beta-defensin proteins, expressed in the epididymis, continue to regulate sperm motility during capacitation and hyperactivation in the female reproductive tract. We characterized the mouse beta-defensin 41 (DEFB41), by generating a mouse model with iCre recombinase inserted into the first exon of the gene. The homozygous Defb41(iCre/iCre) knock-in mice lacked Defb41 expression and displayed iCre recombinase activity in the principal cells of the proximal epididymis. Heterozygous Defb41(iCre/+) mice can be used to generate epididymis specific conditional knock-out mouse models. Homozygous Defb41(iCre/iCre) sperm displayed a defect in sperm motility with the flagella primarily bending in the pro-hook conformation while capacitated wild-type sperm more often displayed the anti-hook conformation. This led to a reduced straight line motility of Defb41(iCre/iCre) sperm and weaker binding to the oocyte. Thus, DEFB41 is required for proper sperm maturation. PMID:26987518

  5. Flow cytometry analysis reveals a decrease in intracellular sodium during sperm capacitation.

    PubMed

    Escoffier, Jessica; Krapf, Dario; Navarrete, Felipe; Darszon, Alberto; Visconti, Pablo E

    2012-01-15

    Mammalian sperm require time in the female tract in order to be able to fertilize an egg. The physiological changes that render the sperm able to fertilize are known as capacitation. Capacitation is associated with an increase in intracellular pH, an increase in intracellular calcium and phosphorylation of different proteins. This process is also accompanied by the hyperpolarization of the sperm plasma membrane potential. Recently, we presented evidence showing that epithelial Na+ channels (ENaC) are present in mature sperm and that ENaCs are blocked during capacitation. In the present work, we used flow cytometry to analyze changes in intracellular Na+ concentration ([Na+](i)) during capacitation in individual cells. Our results indicate that capacitated sperm have lower Na+ concentrations. Using sperm with green fluorescent protein in their acrosomes, it was shown that the lower [Na+](i) concentration only occurs in sperm having intact acrosomes. ENaC inhibition has been shown in other cell types to depend on the activation of cystic fibrosis transmembrane conductance regulator (CFTR). In non-capacitated sperm, amiloride, an ENaC inhibitor, and genistein, a CFTR activator, caused a decrease in [Na+](i), suggesting that also in these cells [Na+](i) is dependent on the crosstalk between ENaC and CFTR. In addition, PKA inhibition blocked [Na+](i) decrease in capacitated sperm. Altogether, these data are consistent with the hypothesis that the capacitation-associated hyperpolarization involves a decrease in [Na+](i) mediated by inhibition of ENaC and regulated by PKA through activation of CFTR channels. PMID:22302997

  6. Intracytoplasmic sperm injection experiments using the mouse as a model.

    PubMed

    Yanagimachi, R

    1998-04-01

    Due to the existence of ample background information on its reproduction, embryology and genetics, the mouse is potentially an excellent animal model for intracytoplasmic sperm injection (ICSI). Normal fertile mouse offspring have been obtained by ICSI using not only mature (epididymal) and immature (testicular) spermatozoa, but also round spermatids and secondary spermatocytes. This suggests that genomic imprinting of male germ cells is complete before spermiogenesis. Mature mouse spermatozoa carry one or more factors that activate oocytes. This sperm-borne oocyte-activating factor is present in testicular spermatozoa, but not in round spermatids. Thus, at least in the mouse, it seems to appear (or become active) during spermiogenesis. Part of the factor seems to be associated with the perinuclear materials because, when freed from plasma and acrosomal membranes as well as all acrosome components, spermatozoa remain fully capable of activating oocytes by ICSI. Spermatozoa with grossly misshapen heads (e.g. those from the BALB/c mouse) are unable to fertilize oocytes under ordinary in-vivo and in-vitro conditions. However, by ICSI they can fertilize the oocytes, and the zygotes develop into fertile offspring. Inherently poorly motile spermatozoa (of male mice carrying two t haplotypes) are unable to fertilize, but through ICSI they can participate in normal fertilization and embryonic development. Examination of human sperm chromosomes after sperm injection into mouse oocytes revealed that spermatozoa with abnormal head morphology have a significantly higher incidence of chromosome abnormality than those with normal heads, yet the majority of the abnormal spermatozoa have normal chromosomal constitutions. These findings suggest that spermatozoa with aberrant morphology and/or motility are not necessarily genomically abnormal.

  7. Ultrastructure of bovine sperm chromatin.

    PubMed

    Filho, Romualdo Morandi; Beletti, Marcelo Emilio; de Oliveira, Fabio

    2015-12-01

    Mammalian semen chromatin comprises DNA, protamine, and, at lower levels, other proteins. This constitution confers intense compaction to the chromatin, helping to protect the DNA and causing the head of the sperm to be very small, facilitating the safe transport of its genetic contents. It is known that changes in the sperm chromatin compaction lead to fertility problems in bulls, justifying studies of this structure. Although there are theoretical models of sperm chromatin because of its high compaction, there is no morphological evidence of such models. The aim of this study was to demonstrate the ultrastructure of bovine sperm chromatin in an attempt to corroborate the theoretical chromatin models existing today. The isolated bull sperm heads had their chromatin partially unpacked by chemical treatment using sodium dodecyl sulfate (SDS) and dithiothreitol (DTT) and were then embedded in Epon resin. Using an ultramicrotome, ultrathin sections were obtained, which were contrasted with uranyl acetate and lead citrate, and then viewed under transmission electron microscopy. The methodology used allowed the visualization of toroidal structures interconnected by a filamentous nuclear matrix, which is entirely consistent with the most current theoretical models. PMID:26515508

  8. Sperm retrieval during critical illness.

    PubMed

    Powner, David J; Rumohr, Jon A; Lipshultz, Larry I

    2010-06-01

    Objective of this study is to review technical methods to retrieve sperm from critically ill/injured patients after an appropriate family request, possible harmful effects on sperm production/function by ICU medications or concurrent illnesses, and ethical considerations for hospitals and care providers in providing this resource. Design used for this study includes: literature review, PubMed 1998-2009, and authors' files. There are no interventions. In conclusion, although successful and unsuccessful pregnancies following sperm removal from critically-ill patients are reported, no firm probability predictions for either result are known. Acute and chronic diseases that effect the hypothalamic-pituitary-gonadal axis and multiple medications common to the ICU may reduce sperm production or function. Retrieval methods before and after cardio-respiratory death differ and often require intracytoplasmic sperm injection or other in vitro fertilization techniques to achieve a subsequent pregnancy. The proactive development of a collaborative policy/procedure to identify appropriate roles for the hospital, its employees, and affiliated critical care and urology physicians is strongly recommended.

  9. The sperm flagellum counterbend phenomenon

    NASA Astrophysics Data System (ADS)

    Gadelha, Hermes; Gaffney, Eamonn; Goriely, Alain

    2013-11-01

    Recent observations of flagellar counterbend in sperm show that the mechanical induction of curvature in one part of a passive flagellum induces a compensatory countercurvature elsewhere. This apparent paradoxical effect cannot be explained using the standard elastic rod theory of Euler and Bernoulli, or even the more general Cosserat theory of rods. Here, we develop a mechanical model capable of predicting the curvature reversal events observed in eukaryotic flagella. This is achieved by allowing the interaction of deformations in different material directions, by not only accounting for structural bending, but also the elastic forces originating from the cross-linking mechanics. Large amplitude configurations can be described analytically and an excellent match between the model and the observed counterbend deformation was found. This allowed a simultaneous estimation of multiple sperm flagellum material parameters, namely the cross-linking sliding resistance, the bending stiffness and the sperm head junction compliance ratio. Our analysis demonstrates that the counterbend emerges as a fundamental property of sliding resistance, which also suggests that cross-linking proteins may contribute to the regulation of the flagellar waveform in swimming sperm via counterbend mechanics. Finally, we investigate how the counterbend-type dynamics in sperm flagella is affected by viscous dissipation.

  10. No evidence of sperm conjugate formation in an Australian mouse bearing sperm with three hooks

    PubMed Central

    Firman, Renée C; Bentley, Blair; Bowman, Faye; Marchant, Fernando García-Solís; Parthenay, Jahmila; Sawyer, Jessica; Stewart, Tom; O'Shea, James E

    2013-01-01

    Sperm conjugation occurs when two or more sperm physically unite for motility or transport through the female reproductive tract. In many muroid rodent species, sperm conjugates have been shown to form by a single, conspicuous apical hook located on the sperm head. These sperm “trains” have been reported to be highly variable in size and, despite all the heads pointing in roughly the same direction, exhibit a relatively disordered arrangement. In some species, sperm “trains” have been shown to enhance sperm swimming speed, and thus have been suggested to be advantageous in sperm competition. Here, we assessed the behavior of sperm in the sandy inland mouse (Pseudomys hermannsburgensis), a muroid rodent that bears sperm with three apical hooks. First, we accrued genetic evidence of multiple paternity within “wild” litters to unequivocally show that sperm competition does occur in this species. Following this we utilized both in vitro and in vivo methodologies to determine whether sandy inland mouse sperm conjugate to form motile trains. Our observations of in vitro preparations of active sperm revealed that sandy inland mouse sperm exhibit rapid, progressive motility as individual cells only. Similarly, histological sections of the reproductive tracts of mated females revealed no in vivo evidence of sperm conjugate formation. We conclude that the unique, three-hooked morphology of the sandy inland mouse sperm does not facilitate the formation of motile conjugates, and discuss our findings in relation to the different hypotheses for the evolution of the muroid rodent hook/s. PMID:23919134

  11. Protective effects of vitamin E and Cornus mas fruit extract on methotrexate-induced cytotoxicity in sperms of adult mice

    PubMed Central

    Zarei, Leila; Sadrkhanlou, Rajabali; Shahrooz, Rasoul; Malekinejad, Hassan; Eilkhanizadeh, Behroz; Ahmadi, Abbas

    2014-01-01

    This study was aimed to assess the protective effects of Cornus mas fruit extract (CMFE) and vitamin E (Vit E) on sperm quality parameters in the methotrexate (MTX)-treated mice. Forty-eight young adult male mice (8-12 weeks) were randomly divided into six groups including control and test groups. The control group received normal saline orally , and the test groups were treated MTX (20 mg kg-1, ip, once weekly), MTX + CMFE (250 mg kg-1), MTX + CMFE (500 mg kg-1), MTX + CMFE (1000 mg kg-1), and MTX + Vit E (100 IU kg-1, po) for 35 consecutive days. On day 35, after euthanasia the epididymal sperms were isolated. Then the total mean sperm count, sperm viability and motility were determined. The total antioxidant capacity (TAOC) of all experimental groups were also evaluated. The MTX-treated animals showed a significant changes in all parameters of sperm quality assessment compared to the control group. Both Vit E and CMFE were able to protect from MTX-induced effects on sperm maturity and DNA damage. Co-administration of MTX and CMFE and/or Vit E resulted in protection from MTX-reduced TAOC. In conclusion, these data suggested that MTX administration could adversely affect the sperm quality. Moreover, the protective effect of Vit E and CMFE on MTX-induced sperm toxicity was also documented. PMID:25568688

  12. Sperm storage and antioxidative enzyme expression in the honey bee, Apis mellifera.

    PubMed

    Collins, A M; Williams, V; Evans, J D

    2004-04-01

    Honey bee (Apis mellifera) sperm remains viable in the spermatheca of mated female honey bees for several years. During this time, the sperm retains respiratory activity, placing it at risk of the damaging effects of reactive oxygen species common to many biological processes. Antioxidative enzymes might help reduce this damage. Here we use quantitative real-time RT-PCR to establish gene-expression profiles in male and female honey bee reproductive tissues for three antioxidative enzymes: catalase, glutathione-S-transferase (GST) and superoxide dismutase (SOD1, cytosolic). Catalase and GST showed ten- to twenty-fold transcript increases in the sperm storage organs of mated queens vs. unmated queens, whereas SOD1 levels are high in both mated and unmated queens. Male reproductive and somatic tissues showed relatively high levels of all three antioxidant-encoding transcripts. All three enzymes screened were higher in mature males vs. young males, although this effect did not appear to be confined to reproductive tissues and, hence, need not reflect a role in sperm longevity. Furthermore, antioxidative enzyme transcripts remained present, and apparently increased, in male tissues long after sperm had matured and seminal fluid was produced. We also found measurable levels of catalase transcripts in honey bee semen. The presence of catalase transcripts in both reproductive tissues and semen in bees suggests that this enzyme might play a key role in antioxidative protection.

  13. Human sperm rheotaxis: a passive physical process.

    PubMed

    Zhang, Zhuoran; Liu, Jun; Meriano, Jim; Ru, Changhai; Xie, Shaorong; Luo, Jun; Sun, Yu

    2016-01-01

    A long-standing question in natural reproduction is how mammalian sperm navigate inside female reproductive tract and finally reach the egg cell, or oocyte. Recently, fluid flow was proposed as a long-range guidance cue for sperm navigation. Coitus induces fluid flow from oviduct to uterus, and sperm align themselves against the flow direction and swim upstream, a phenomenon termed rheotaxis. Whether sperm rheotaxis is a passive process dominated by fluid mechanics, or sperm actively sense and adapt to fluid flow remains controversial. Here we report the first quantitative study of sperm flagellar motion during human sperm rheotaxis and provide direct evidence indicating that sperm rheotaxis is a passive process. Experimental results show that there is no significant difference in flagellar beating amplitude and asymmetry between rheotaxis-turning sperm and those sperm swimming freely in the absence of fluid flow. Additionally, fluorescence image tracking shows no Ca(2+) influx during sperm rheotaxis turning, further suggesting there is no active signal transduction during human sperm rheotaxis. PMID:27005727

  14. SPERM COUNT DISTRIBUTIONS IN FERTILE MEN

    EPA Science Inventory

    Sperm concentration and count are often used as indicators of environmental impacts on male reproductive health. Existing clinical databases may be biased towards subfertile men with low sperm counts and less is known about expected sperm count distributions in cohorts of fertil...

  15. Human sperm rheotaxis: a passive physical process

    NASA Astrophysics Data System (ADS)

    Zhang, Zhuoran; Liu, Jun; Meriano, Jim; Ru, Changhai; Xie, Shaorong; Luo, Jun; Sun, Yu

    2016-03-01

    A long-standing question in natural reproduction is how mammalian sperm navigate inside female reproductive tract and finally reach the egg cell, or oocyte. Recently, fluid flow was proposed as a long–range guidance cue for sperm navigation. Coitus induces fluid flow from oviduct to uterus, and sperm align themselves against the flow direction and swim upstream, a phenomenon termed rheotaxis. Whether sperm rheotaxis is a passive process dominated by fluid mechanics, or sperm actively sense and adapt to fluid flow remains controversial. Here we report the first quantitative study of sperm flagellar motion during human sperm rheotaxis and provide direct evidence indicating that sperm rheotaxis is a passive process. Experimental results show that there is no significant difference in flagellar beating amplitude and asymmetry between rheotaxis-turning sperm and those sperm swimming freely in the absence of fluid flow. Additionally, fluorescence image tracking shows no Ca2+ influx during sperm rheotaxis turning, further suggesting there is no active signal transduction during human sperm rheotaxis.

  16. Human sperm rheotaxis: a passive physical process

    PubMed Central

    Zhang, Zhuoran; Liu, Jun; Meriano, Jim; Ru, Changhai; Xie, Shaorong; Luo, Jun; Sun, Yu

    2016-01-01

    A long-standing question in natural reproduction is how mammalian sperm navigate inside female reproductive tract and finally reach the egg cell, or oocyte. Recently, fluid flow was proposed as a long–range guidance cue for sperm navigation. Coitus induces fluid flow from oviduct to uterus, and sperm align themselves against the flow direction and swim upstream, a phenomenon termed rheotaxis. Whether sperm rheotaxis is a passive process dominated by fluid mechanics, or sperm actively sense and adapt to fluid flow remains controversial. Here we report the first quantitative study of sperm flagellar motion during human sperm rheotaxis and provide direct evidence indicating that sperm rheotaxis is a passive process. Experimental results show that there is no significant difference in flagellar beating amplitude and asymmetry between rheotaxis-turning sperm and those sperm swimming freely in the absence of fluid flow. Additionally, fluorescence image tracking shows no Ca2+ influx during sperm rheotaxis turning, further suggesting there is no active signal transduction during human sperm rheotaxis. PMID:27005727

  17. Easy sperm processing technique allowing exclusive accumulation and later usage of DNA-strandbreak-free spermatozoa.

    PubMed

    Ebner, T; Shebl, O; Moser, M; Mayer, R B; Arzt, W; Tews, G

    2011-01-01

    Sperm DNA fragmentation is increased in poor-quality semen samples and correlates with failed fertilization, impaired preimplantation development and reduced pregnancy outcome. Common sperm preparation techniques may reduce the percentage of strandbreak-positive spermatozoa, but, to date, there is no reliable approach to exclusively accumulate strandbreak-free spermatozoa. To analyse the efficiency of special sperm selection chambers (Zech-selectors made of glass or polyethylene) in terms of strandbreak reduction, 39 subfertile men were recruited and three probes (native, density gradient and Zech-selector) were used to check for strand breaks using the sperm chromatin dispersion test. The mean percentage of affected spermatozoa in the ejaculate was 15.8 ± 7.8% (range 5.0–42.1%). Density gradient did not significantly improve the quality of spermatozoa selected(14.2 ± 7.0%). However, glass chambers completely removed 90% spermatozoa showing strand breaks and polyethylene chambers removed 76%. Both types of Zech-selectors were equivalent in their efficiency, significantly reduced DNA damage (P < 0.001) and,with respect to this, performed better than density gradient centrifugation (P < 0.001). As far as is known, this is the first report ona sperm preparation technique concentrating spermatozoa unaffected in terms of DNA damage. The special chambers most probably select for sperm motility and/or maturity.

  18. Live Pups from Evaporatively Dried Mouse Sperm Stored at Ambient Temperature for up to 2 Years

    PubMed Central

    Liu, Jie; Lee, Gloria Y.; Lawitts, Joel A.; Toner, Mehmet; Biggers, John D.

    2014-01-01

    The purpose of this study is to develop a mouse sperm preservation method based on evaporative drying. Mouse sperm were evaporatively dried and stored at 4°C and ambient temperature for 3 months to 2 years. Upon rehydration, a single sperm was injected into a mature oocyte to develop into a blastocyst after culture or a live birth after embryo transfer to a recipient female. For the samples stored at 4°C for 3, 6, 12, 18, and 24 months, the blastocyst formation rate was 61.5%, 49.1%, 31.5%, 32.2%, and 41.4%, respectively. The blastocyst rate for those stored at ambient temperature (∼22°C) for 3, 6, 12, and 18 months was 57.8%, 36.2%, 33.6%, and 34.4%, respectively. Fifteen, eight and three live pups were produced from sperm stored at room temperature for 12, 18, and 24 months, respectively. This is the first report of live offspring produced from dried mouse sperm stored at ambient temperature for up to 2 years. Based on these results, we suggest that evaporative drying is a potentially useful method for the routine preservation of mouse sperm. PMID:24924588

  19. Sperm head vacuoles are not affected by in-vitro conditions, as analysed by a system of sperm-microcapture channels.

    PubMed

    Neyer, Anton; Vanderzwalmen, Pierre; Bach, Magnus; Stecher, Astrid; Spitzer, Dietmar; Zech, Nicolas

    2013-04-01

    Since the introduction of the motile sperm organelle morphology examination, there has been increasing recognition of the fact that the presence of large nuclear vacuoles might have deleterious effects on embryo development. Nevertheless, one fundamental question still being debated is whether specific in-vitro conditions during the handling of semen have an impact on vacuole formation. This study's objective was to analyse whether incubation temperature (20, 37°C) or oxidative stress stimulates the formation of nuclear vacuoles. Furthermore, it examined whether vacuoles disappear in the presence of an acrosome reaction inducer. Therefore, a system of sperm-microcapture channels was developed to permit the observation of the same living spermatozoa over a period of 24h. Neither incubation at 37°C nor induction of oxidative stress led to de-novo formation of nuclear vacuoles. Induction of the acrosome reaction using calcium ionophore A23587 did not lead to any modifications in the proportion of spermatozoa with vacuoles or to the disappearance of pre-existing vacuoles. According to these observations, it is concluded that nuclear vacuoles on the sperm head are already produced at earlier stages of sperm maturation and are not induced or modulated by routine laboratory environments. The examination of spermatozoa at very high magnification has led to the increasingly widespread recognition that the presence of large vacuoles in the human sperm head has deleterious effects on embryo development. One fundamental question, however, still remains: do specific conditions in the laboratory during the preparation and the handling of semen have an impact on vacuole formation? Our initial objective was to analyse whether different incubation temperatures (20, 37°C) and the induction of oxidative stress lead to the formation of sperm head vacuoles. Furthermore, we examined whether vacuoles disappear in the presence of an acrosome reaction inducer. In order to do this we

  20. A cost for high levels of sperm competition in rodents: increased sperm DNA fragmentation.

    PubMed

    delBarco-Trillo, Javier; García-Álvarez, Olga; Soler, Ana Josefa; Tourmente, Maximiliano; Garde, José Julián; Roldan, Eduardo R S

    2016-03-16

    Sperm competition, a prevalent evolutionary process in which the spermatozoa of two or more males compete for the fertilization of the same ovum, leads to morphological and physiological adaptations, including increases in energetic metabolism that may serve to propel sperm faster but that may have negative effects on DNA integrity. Sperm DNA damage is associated with reduced rates of fertilization, embryo and fetal loss, offspring mortality, and mutations leading to genetic disease. We tested whether high levels of sperm competition affect sperm DNA integrity. We evaluated sperm DNA integrity in 18 species of rodents that differ in their levels of sperm competition using the sperm chromatin structure assay. DNA integrity was assessed upon sperm collection, in response to incubation under capacitating or non-capacitating conditions, and after exposure to physical and chemical stressors. Sperm DNA was very resistant to physical and chemical stressors, whereas incubation in non-capacitating and capacitating conditions resulted in only a small increase in sperm DNA damage. Importantly, levels of sperm competition were positively associated with sperm DNA fragmentation across rodent species. This is the first evidence showing that high levels of sperm competition lead to an important cost in the form of increased sperm DNA damage.

  1. Sperm head binding to epithelium of the oviduct isthmus is not an essential preliminary to mammalian fertilization - review.

    PubMed

    Hunter, R H F

    2011-08-01

    In endeavouring to understand the nature of sperm-oviduct interactions in mammals, attention was focused on experimental models in which fertilization can occur without a preliminary phase of sperm head binding to the isthmus epithelium. The ovarian endocrine milieu imposed on the oviduct tissues plays an important role in the binding phenomenon, although less so after the time of ovulation. Nonetheless, a sperm suspension introduced into the peritoneal cavity or surgical insemination directly into the oviduct ampulla before ovulation can result in fertilization, as can a surgical model in which the isthmus has been resected and the remaining portions of the duct reanastomosed. Mating or artificial insemination after ovulation in pigs permits rapid sperm transport to the site of fertilization, and the frequency of polyspermic penetration increases with the post-ovulatory age of eggs.Strategies underlying sperm binding were considered, especially in terms of preovulatory sperm storage and suppression of full membranous maturation. These, in turn, raised the problem of how sperm binding in vitro to oviduct cells from prepuberal animals or to cells harvested during the luteal phase of the estrous cycle, or to cells from the ampulla or even the tracheal epithelium, can act to regulate sperm storage and maturation with precision. In an evolutionary perspective, preovulatory binding of diverse populations of cells to the endosalpinx may have developed as a form of fine tuning to assist in sperm selection, to synchronize completion of capacitation with the events of ovulation, and to promote monospermic fertilization by a controlled release of competent gametes.

  2. Roles of the reproductive tract in modifications of the sperm membrane surface

    PubMed Central

    KUO, Yu-Wen; LI, Sheng-Hsiang; MAEDA, Kei-Ichiro; GADELLA, Bart M.; TSAI, Pei Shiue J.

    2016-01-01

    Successful fertilization requires viable and functional spermatozoa to recognize and fuse with the oocyte. In most mammalian species, mature spermatozoa are not capable of fertilizing the oocytes immediately after ejaculation. However, unlike somatic cells, spermatozoa, after leaving the testis, are transcriptionally and translationally silent; therefore, upon completion of spermiogenesis, spermatozoa carry only a minimal amount of essential proteins on their membranes as well as within their restricted volume of cytoplasm. To develop into a fully functional and competent sperm that is capable of successful fertilization, modifications of the sperm membrane surface during its transit in the reproductive tracts is critical. These post-spermatogenesis modifications advance the maturation of epididymal spermatozoa. In addition, components secreted into the lumen of the reproductive tracts that are later added onto the sperm membrane surface also regulate (inhibit or activate) the functions of the spermatozoa. This acquisition of additional proteins from the reproductive tracts may compensate for the inactivity of morphologically mature spermatozoa. In this review, we discuss the contributions of the male and female genital tracts to modifications of the sperm membrane surface at different stages of fertilization. PMID:27009019

  3. Flow cytometric sexing of mammalian sperm.

    PubMed

    Garner, Duane L

    2006-03-15

    This review reexamines parameters needed for optimization of flow cytometric sexing mammalian sperm and updates the current status of sperm sexing for various species where this technology is currently being applied. Differences in DNA content have provided both a method to differentiate between these sex-determining gametes and a method to sort them that can be used for predetermining sex in mammals. Although the DNA content of all cells for each mammalian species is highly conserved, slight but measurable DNA content differences of sperm occur within species even among cattle breeds due to different sizes of Y-chromosomes. Most mammals produce flattened, oval-headed sperm that can be oriented within a sorter using hydrodynamic forces. Multiplying the percentage the difference in DNA content of the X- or Y-chromosome bearing sperm times the area of the flat profile of the sperm head gives a simple sorting index that suggests that bull and boar sperm are well suited for separation in a flow sorter. Successful sperm sexing of various species must take into account the relative susceptibilities of gametes to the stresses that occur during sexing. Sorting conditions must be optimized for each species to achieve acceptable sperm sexing efficiency, usually at 90% accuracy. In the commercial application of sperm sexing to cattle, fertility of sex-sorted bull sperm at 2 x 10(6)/dose remains at 70-80% of unsexed sperm at normal doses of 10 to 20 x 10(6) sperm. DNA content measurements have been used to identify the sex-chromosome bearing sperm populations with good accuracy in semen from at least 23 mammalian species, and normal-appearing offspring have been produced from sexed sperm of at least seven species. PMID:16242764

  4. Reactive oxygen species and boar sperm function.

    PubMed

    Awda, Basim J; Mackenzie-Bell, Meghan; Buhr, Mary M

    2009-09-01

    Boar spermatozoa are very susceptible to reactive oxygen species (ROS), but ROS involvement in damage and/or capacitation is unclear. The impact of exposing fresh boar spermatozoa to an ROS-generating system (xanthine/xanthine oxidase; XA/XO) on sperm ROS content, membrane lipid peroxidation, phospholipase (PL) A activity, and motility, viability, and capacitation was contrasted to ROS content and sperm function after cryopreservation. Exposing boar sperm (n = 4-5 ejaculates) to the ROS-generating system for 30 min rapidly increased hydrogen peroxide (H2O2) and lipid peroxidation in all sperm, increased PLA in dead sperm, and did not affect intracellular O2- (flow cytometry of sperm labeled with 2',7'-dichlorodihydrofluorscein diacetate, BODIPY 581/591 C11, bis-BODIPY-FL C11, hydroethidine, respectively; counterstained for viability). Sperm viability remained high, but sperm became immotile. Cryopreservation decreased sperm motility, viability, and intracellular O2- significantly, but did not affect H2O2. As expected, more sperm incubated in capacitating media than Beltsville thawing solution buffer underwent acrosome reactions and protein tyrosine phosphorylation (four proteins, 58-174 kDa); which proteins were tyrosine phosphorylated was pH dependent. Pre-exposing sperm to the ROS-generating system increased the percentage of sperm that underwent acrosome reactions after incubation in capacitating conditions (P < 0.025), and decreased capacitation-dependent increases in two tyrosine-phosphorylated proteins (P < or = 0.035). In summary, H2O2 is the major free radical mediating direct ROS effects, but not cryopreservation changes, on boar sperm. Boar sperm motility, acrosome integrity, and lipid peroxidation are more sensitive indicators of oxidative stress than viability and PLA activity. ROS may stimulate the acrosome reaction in boar sperm through membrane lipid peroxidation and PLA activation. PMID:19357363

  5. Spermiogenesis and Taxonomical Values of Sperm Ultrastructures in Male Crassostrea ariakensis (Fujita & Wakiya, 1929) (Pteroirmorphia: Ostreidae) in the Estuary of the Seomjin River, Korea

    PubMed Central

    Son, Pal Won; Chung, Jae Seung; Kim, Jin Hee; Kim, Sung Han; Chung, Ee-Yung

    2014-01-01

    Characteristics of the developmental stages of spermatids during spermiogenesis and phylogenetic classicfication of the species using sperm ultrastructures in male Crassostrea ariakensis were investigated by transmission electron microscope observations. The morphology of the spermatozoon of this species has a primitive type and is similar to those of Ostreidae. Ultrastructures of mature sperms are composed of broad, modified cap-shaped acrosomal vesicle and an axial rod in subacrosomal materials on an oval nucleus, four spherical mitochondria in the sperm midpiece, and satellite fibres which appear near the distal centriole. The axoneme of the sperm tail shows a 9+2 structure. Accordingly, the ultrastructural characteristics of mature sperm of C. ariakensis resemble to those of other investigated ostreids in Ostreidae in the subclass Pteriomorphia. In this study, particularly, two transverse bands (stripes) appear at the anterior region of the acrosomal vesicle of this species, unlike two or three transverse bands (stripes) in C. gigas. It is assumed that differences in this acrosomal substructure are associated with the inability of fertilization between the genus Crassostrea and other genus species in Ostreidae. Therefore, we can use sperm ultrastructures and morphologies in the resolution of taxonomic relationships within the Ostreidae in the subclass Pteriomorphia. These spermatozoa, which contain several ultrastructures such as acrosomal vesicle, an axial rod in the sperm head part and four mitochondria and satellite fibres in the sperm midpiece, belong to the family Ostreidae in the subclass Pteriomorphia. PMID:25949188

  6. Spermiogenesis and Taxonomical Values of Sperm Ultrastructures in Male Crassostrea ariakensis (Fujita & Wakiya, 1929) (Pteroirmorphia: Ostreidae) in the Estuary of the Seomjin River, Korea.

    PubMed

    Son, Pal Won; Chung, Jae Seung; Kim, Jin Hee; Kim, Sung Han; Chung, Ee-Yung

    2014-09-01

    Characteristics of the developmental stages of spermatids during spermiogenesis and phylogenetic classicfication of the species using sperm ultrastructures in male Crassostrea ariakensis were investigated by transmission electron microscope observations. The morphology of the spermatozoon of this species has a primitive type and is similar to those of Ostreidae. Ultrastructures of mature sperms are composed of broad, modified cap-shaped acrosomal vesicle and an axial rod in subacrosomal materials on an oval nucleus, four spherical mitochondria in the sperm midpiece, and satellite fibres which appear near the distal centriole. The axoneme of the sperm tail shows a 9+2 structure. Accordingly, the ultrastructural characteristics of mature sperm of C. ariakensis resemble to those of other investigated ostreids in Ostreidae in the subclass Pteriomorphia. In this study, particularly, two transverse bands (stripes) appear at the anterior region of the acrosomal vesicle of this species, unlike two or three transverse bands (stripes) in C. gigas. It is assumed that differences in this acrosomal substructure are associated with the inability of fertilization between the genus Crassostrea and other genus species in Ostreidae. Therefore, we can use sperm ultrastructures and morphologies in the resolution of taxonomic relationships within the Ostreidae in the subclass Pteriomorphia. These spermatozoa, which contain several ultrastructures such as acrosomal vesicle, an axial rod in the sperm head part and four mitochondria and satellite fibres in the sperm midpiece, belong to the family Ostreidae in the subclass Pteriomorphia. PMID:25949188

  7. Markers of human sperm functions in the ICSI era.

    PubMed

    Muratori, Monica; Marchiani, Sara; Tamburrino, Lara; Forti, Gianni; Luconi, Michaela; Baldi, Elisabetta

    2011-01-01

    The process of fertilization is crucial for species development and maintenance. Due to social and environmental problems, the number of infertile couples is increasing worldwide. Male and female factors contribute equally, and about 7% of men experiences problems in conceiving a child due to sperm defects. Assisted reproduction techniques (ARTs), including the most invasive intracytoplasmic sperm injection (ICSI), are the only available therapy for severe male factor infertility. Whether such techniques are associated with increased birth defects is still debated, and search for alternative options should go on. A better understanding of the molecular mechanisms involved in the process of fertilization may lead to the development of new pharmacological strategies to treat infertile men and new male contraceptive agents. In addition, in view of the low predictive power of routine semen analysis, new tests aimed to better predict the fertilization potential could be developed. The present review summarizes current evidence of the molecular mechanisms involved in fertilization in human spermatozoa, with particular emphasis on the main post-ejaculatory maturation events, i.e. sperm capacitation and motility.

  8. [Analysis of sperm morphology: yes or no?].

    PubMed

    Lu, Jin-Chun

    2013-04-01

    The analysis of sperm morphology can be used to evaluate sperm fertilizing ability and spontaneous conception status, and especially the overall analysis of the sperm head, neck and tail, along with the patient's living habits, occupation and clinical manifestations, may contribute to the primary diagnosis of the patients potentia generandi. It can also be employed to assess the effects of the treatment of semen samples. Although oocyte fertilization can be achieved by the technologies of intracytoplasmic sperm injection (ICSI), motile sperm organelle morphology examination (MSOME) and intracytoplasmic morphologically selected sperm injection (IMSI) regardless of sperm morphology and / or motility, which may somewhat weaken the clinical application of sperm morphology analysis, the standardized procedure and the practice of quality control for the analysis of sperm morphology can significantly improve the accuracy of its results and largely promote its clinical application. Therefore, it is of positive necessity as well as clinical application value to perform sperm morphology analysis in andrology laboratories, reproductive centers, sperm banks and the department of laboratory medicine.

  9. Sperm in "parhenogenetic" freshwater gastrotrichs.

    PubMed

    Weiss, M J; Levy, D P

    1979-07-20

    Freshwater members of the phylum Gastrotricha have been considered obligate parthenogens. In Lepidodermelia squammata, the species for which there is most evidence for parthenogenesis, sperm have been discovered. This finding will necessitate reexamination of the nature of sexuality and life cycles and of the concept of "species" in freshwater gastrotrichs. PMID:17747043

  10. Sperm in "parhenogenetic" freshwater gastrotrichs.

    PubMed

    Weiss, M J; Levy, D P

    1979-07-20

    Freshwater members of the phylum Gastrotricha have been considered obligate parthenogens. In Lepidodermelia squammata, the species for which there is most evidence for parthenogenesis, sperm have been discovered. This finding will necessitate reexamination of the nature of sexuality and life cycles and of the concept of "species" in freshwater gastrotrichs.

  11. Intracytoplasmic morphology-selected sperm injection.

    PubMed

    Simon, Luke; Wilcox, Aaron; Carrell, Douglas T

    2013-01-01

    Approximately 40% of sterility in couples can be attributed to male subfertility and intracytoplasmic sperm injection (ICSI) has become a powerful tool in assisted reproduction to overcome male infertility. Intracytoplasmic morphologically selected sperm injection (IMSI) is an advanced and sophisticated method of ICSI, where prior to sperm injection the morphology of the sperm is evaluated under high magnification. In addition, the IMSI procedure involves a few minor modifications in sperm preparation which are not carried out during the conventional ICSI procedure, such as the use of MSOME criteria, the requirement for a glass-bottomed dish for selection, prolonged sperm manipulation following separation from the seminal fluid, and sperm storage prior to microinjection. These variations are discussed in this chapter.

  12. Nuclear microscopy of sperm cell elemental structure

    SciTech Connect

    Bench, G.S.

    1994-12-31

    Theories have suggested that there is a link between protamine concentrations in individual sperm and sperm fertility. At present, biochemical analyses have only been performed on bulk populations and existing methods have not been able to determine what percentage of morphologically normal sperm are biochemically defective and potentially infertile. As part of an investigation into male sperm fertility, nuclear microscopy has been utilized to measure elemental profiles at the single sperm level. By measuring the ratio of Phosphorus to Sulfur the authors have been able to determine the amount of protamine 1 and protamine 2 in individual cells from bulk fertile samples of bull and mouse sperm. Preliminary results show that, for each species, the relative amounts of protamine 1 and protamine 2 in morphologically normal sperm agree well with expected values.

  13. Effect of male age on sperm traits and sperm competition success in the guppy (Poecilia reticulata).

    PubMed

    Gasparini, C; Marino, I A M; Boschetto, C; Pilastro, A

    2010-01-01

    Deleterious mutations can accumulate in the germline with age, decreasing the genetic quality of sperm and imposing a cost on female fitness. If these mutations also affect sperm competition ability or sperm production, then females will benefit from polyandry as it incites sperm competition and, consequently, minimizes the mutational load in the offspring. We tested this hypothesis in the guppy (Poecilia reticulata), a species characterized by polyandry and intense sperm competition, by investigating whether age affects post-copulatory male traits and sperm competition success. Females did not discriminate between old and young males in a mate choice experiment. While old males produced longer and slower sperm with larger reserves of strippable sperm, compared to young males, artificial insemination did not reveal any effect of age on sperm competition success. Altogether, these results do not support the hypothesis that polyandry evolved in response to costs associated with mating with old males in the guppy.

  14. Phenotypic engineering of sperm-production rate confirms evolutionary predictions of sperm competition theory

    PubMed Central

    Sekii, Kiyono; Vizoso, Dita B.; Kuales, Georg; De Mulder, Katrien; Ladurner, Peter; Schärer, Lukas

    2013-01-01

    Sperm production is a key male reproductive trait and an important parameter in sperm competition theory. Under sperm competition, paternity success is predicted to depend strongly on male allocation to sperm production. Furthermore, because sperm production is inherently costly, individuals should economize in sperm expenditure, and conditional adjustment of the copulation frequency according to their sperm availability may be expected. However, experimental studies showing effects of sperm production on mating behaviour and paternity success have so far been scarce, mainly because sperm production is difficult to manipulate directly in animals. Here, we used phenotypic engineering to manipulate sperm-production rate, by employing dose-dependent RNA interference (RNAi) of a spermatogenesis-specific gene, macbol1, in the free-living flatworm Macrostomum lignano. We demonstrate (i) that our novel dose-dependent RNAi approach allows us to induce high variability in sperm-production rate; (ii) that a reduced sperm-production rate is associated with a decreased copulation frequency, suggesting conditional adjustment of mating behaviour; and (iii) that both sperm production and copulation frequency are important determinants of paternity success in a competitive situation, as predicted by sperm competition theory. Our study clearly documents the potential of phenotypic engineering via dose-dependent RNAi to test quantitative predictions of evolutionary theory. PMID:23446521

  15. Sperm release strategies in marine broadcast spawners: the costs of releasing sperm quickly.

    PubMed

    Marshall, Dustin J; Bolton, Toby F

    2007-11-01

    When under competition for fertilisations, males are thought to increase their reproductive success by releasing as many sperm as possible into the reproductive arena and in many species, this prediction holds. For marine invertebrates, which utilise the ancestral strategy of broadcast spawning eggs and sperm, however, it appears that males tend to release their sperm more slowly than females release their eggs. Marine invertebrate eggs typically have a relatively slow permanent block to polyspermy (whereby eggs become impermeable to further sperm attachment), and for several minutes after fertilisation, sperm can continue to attach to a fertilised egg. We hypothesised that releasing sperm slowly minimises the 'wastage' of sperm on already fertilised eggs. We simulated different sperm release rates in a flume using the broadcast spawning polychaete, Galeolaria caespitosa. Sperm release rates strongly affected overall fertilisation success: higher release rates resulted in lower fertilisation rates. Laboratory studies confirmed that the 'permanent' block to polyspermy in G. caespitosa took less than a minute to form but this lag was sufficient to result in some sperm wastage. Thus upstream, fertilised eggs that have not formed a permanent block to polyspermy can remove sperm from the pool that would otherwise fertilise downstream sibling eggs. We suggest that while electrical blocks to polyspermy evolved in response to excess sperm, permanent blocks to polyspermy could have evolved in response to sperm limitation (insufficient sperm).

  16. SLC6 family transporter SNF-10 is required for protease-mediated activation of sperm motility in C. elegans.

    PubMed

    Fenker, Kristin E; Hansen, Angela A; Chong, Conrad A; Jud, Molly C; Duffy, Brittany A; Norton, J Paul; Hansen, Jody M; Stanfield, Gillian M

    2014-09-01

    Motility of sperm is crucial for their directed migration to the egg. The acquisition and modulation of motility are regulated to ensure that sperm move when and where needed, thereby promoting reproductive success. One specific example of this phenomenon occurs during differentiation of the ameboid sperm of Caenorhabditis elegans as they activate from a round spermatid to a mature, crawling spermatozoon. Sperm activation is regulated by redundant pathways to occur at a specific time and place for each sex. Here, we report the identification of the solute carrier 6 (SLC6) transporter protein SNF-10 as a key regulator of C. elegans sperm activation in response to male protease activation signals. We find that SNF-10 is present in sperm and is required for activation by the male but not by the hermaphrodite. Loss of both snf-10 and a hermaphrodite activation factor render sperm completely insensitive to activation. Using in vitro assays, we find that snf-10 mutant sperm show a specific deficit in response to protease treatment but not to other activators. Prior to activation, SNF-10 is present in the plasma membrane, where it represents a strong candidate to receive signals that lead to subcellular morphogenesis. After activation, it shows polarized localization to the cell body region that is dependent on membrane fusions mediated by the dysferlin FER-1. Our discovery of snf-10 offers insight into the mechanisms differentially employed by the two sexes to accomplish the common goal of producing functional sperm, as well as how the physiology of nematode sperm may be regulated to control motility as it is in mammals.

  17. Lifestyle factors and sperm aneuploidy.

    PubMed

    Jurewicz, Joanna; Radwan, Michał; Sobala, Wojciech; Radwan, Paweł; Jakubowski, Lucjusz; Hawuła, Wanda; Ulańska, Anna; Hanke, Wojciech

    2014-09-01

    Different environmental and lifestyle factors may interfere with the normal disjunction of sister chromatids/chromosomes during meiosis and may cause aneuploidy. The aim of the study was to examine the association between lifestyle factors and sperm aneuploidy. The study population consisted of 212 healthy men under 45 years of age attending an infertility clinic for diagnostic purposes and who had a normal semen concentration of 20-300×10⁶mL or slight oligozoospermia (semen concentration of 15-20×10⁶/mL). All participants were interviewed and provided a semen sample. Sperm aneuploidy was assessed using multicolor FISH (DNA probes specific for chromosomes X, Y, 18, 13, 21). Results from the study suggest that lifestyle factors are related to sperm aneuploidy. A positive relationship was found between coffee drinking everyday and the lack of chromosome X or Y, as well as coffee drinking 1-6 times per week and additional chromosome 18. Wearing boxer shorts decrease the copy number changes in the whole chromosome 18, the number of additional chromosome 18 and the lack of chromosome 13. Additionally, obesity (BMI 30-40 kg/m²) was positively associated with additional chromosome 21 after being adjusted for potential confounders. These findings demonstrate that changing the men's lifestyle habits may contribute to reduction of the incidence of sperm aneuploidy. It is necessary that men continue to follow sensible health advice concerning excess weight, coffee drinking and wearing tight fitting underwear. As this is the first such study to examine different lifestyle factors and sperm aneuploidy, the results need to be confirmed on larger population.

  18. Mechanisms underlying the sperm quality advantage in Drosophila melanogaster.

    PubMed

    Pattarini, James M; Starmer, William T; Bjork, Adam; Pitnick, Scott

    2006-10-01

    Contrary to early predictions of sperm competition theory, postcopulatory sexual selection favoring increased investment per sperm (e.g., sperm size, sperm quality) has been demonstrated in numerous organisms. We empirically demonstrate for Drosophila melanogaster that both sperm quality and sperm quantity independently contribute to competitive male fertilization success. In addition to these independent effects, there was a significant interaction between sperm quality and quantity that suggests an internal positive reinforcement on selection for sperm quality, with selection predicted to intensify as investment per sperm increases and the number of sperm competing declines. The mechanism underlying the sperm quality advantage is elucidated through examination of the relationship between female sperm-storage organ morphology and the differential organization of different length sperm within the organ. Our results exemplify that primary sex cells can bear secondary sexual straits.

  19. Sperm quality in the alternative reproductive tactics of Atlantic salmon: the importance of the loaded raffle mechanism.

    PubMed Central

    Vladić, T. V.; Järvi, T.

    2001-01-01

    The outcome of sperm competition in species with alternative male reproductive strategies may be determined by fair or loaded raffle mechanisms. The sperm production and quality of male Atlantic salmon using alternative reproductive tactics were investigated in order to determine the relative importance of sperm quality for male reproductive success. Sexually mature resident parr males produced greater numbers of spermatozoa per millilitre of ejaculate and invested more in their gonads as a percentage of body mass than their anadromous counterparts. Parr males had greater proportions of motile spermatozoa and a greater sperm ATP content as compared with anadromous males. Parr males invested relatively more in sperm quality and sperm numbers after the effect of body size was accounted for. In fertilization experiments, parr males fertilized greater proportions of eggs than anadromous males. A polynomial model exhibited a trade-off between testes mass and ejaculate expenditure and explained 60% of the variation. These results establish that, in sperm competition with dominant males, parr males may compensate for behavioural subordinance by producing physiologically superior spermatozoa. PMID:11703878

  20. Impact of glycosylation on the unimpaired functions of the sperm

    PubMed Central

    2015-01-01

    One of the key factors of early development is the specification of competence between the oocyte and the sperm, which occurs during gametogenesis. However, the starting point, growth, and maturation for acquiring competence during spermatogenesis and oogenesis in mammals are very different. Spermatogenesis includes spermiogenesis, but such a metamorphosis is not observed during oogenesis. Glycosylation, a ubiquitous modification, is a preliminary requisite for distribution of the structural and functional components of spermatids for metamorphosis. In addition, glycosylation using epididymal or female genital secretory glycans is an important process for the sperm maturation, the acquisition of the potential for fertilization, and the acceleration of early embryo development. However, nonemzymatic unexpected covalent bonding of a carbohydrate and malglycosylation can result in falling fertility rates as shown in the diabetic male. So far, glycosylation during spermatogenesis and the dynamics of the plasma membrane in the process of capacitation and fertilization have been evaluated, and a powerful role of glycosylation in spermatogenesis and early development is also suggested by structural bioinformatics, functional genomics, and functional proteomics. Further understanding of glycosylation is needed to provide a better understanding of fertilization and embryo development and for the development of new diagnostic and therapeutic tools for infertility. PMID:26473106

  1. Phagocytosis of sperm by follicle cells of the carnivorous sponge Asbestopluma occidentalis (Porifera, Demospongiae).

    PubMed

    Riesgo, Ana

    2010-06-01

    During spermatogenesis of the carnivorous sponge Asbestopluma occidentalis, follicle cells that lined the spermatocysts phagocytosed unreleased mature sperm. Such follicle cells are part of the complex envelope that limits spermatocysts of A. occidentalis, which is also comprised of a collagen layer, a thick layer of intertwined cells, and spicules. Follicle cells showed vesicles containing single phagocytosed spermatozoa within their cytoplasm. Additionally, lipids and other inclusions were observed within the cytoplasm of follicle cells. It is likely that follicle cells recapture nutrients by phagocytosing spermatozoa and use them to form lipids and other inclusions. Such sperm phagocytosis is usually performed in higher invertebrates and vertebrates by Sertoli cells that are located in the testis wall. While Sertoli cells develop a wide range of functions such as creating a blood-testis barrier, providing crucial factors to ensure correct progression of spermatogenesis, and phagocytosis of aberrant, degenerating, and unreleased sperm cells, sponge follicle cells may only display phagocytotic activity on spermatogenic cells.

  2. Sperm morphology of salamandrids (Amphibia, Urodela): implications for phylogeny and fertilization biology.

    PubMed

    Selmi, M G; Brizzi, R; Bigliardi, E

    1997-12-01

    Mature spermatozoa belonging to four salamander species, Salamandrina terdigitata, Triturus alpestris, Triturus carnifex and Triturus vulgaris, have been investigated by electron microscopy. The sperm ultrastructure of these species was compared with that of previously examined urodeles (36 species and 20 genera) and with that of anurans and caecilians. Many phylogenetic considerations may be inferred as a consequence of comparative spermatology. Urodela appears to be a monophyletic order characterized by three sperm synapomorphies: the acrosomal barb, nuclear ridge and marginal filament. Cryptobranchoidea are confirmed to form a monophyletic suborder having two synapomorphic characters: absence of mitochondria in the tail, and cylindrical shape of the tail axial rod. Within the family Salamandridae, sperm morphology confirms the phylogenetic distance between Salamandrina and Triturus, as already pointed out on the basis of molecular and morphological characters. The very complex ultrastructure of spermatozoa confirms a previous opinion that internal fertilization is the ancestral condition of the Amphibia. PMID:18627832

  3. Laser radiation and motility patterns of human sperm

    SciTech Connect

    Lenzi, A.; Claroni, F.; Gandini, L.; Lombardo, F.; Barbieri, C.; Lino, A.; Dondero, F. )

    1989-01-01

    Human sperm were exposed in vitro to laser radiation. An increase in progressive sperm motility was associated with a faster rate of sperm ATP consumption. Computer-assisted analysis of sperm motility confirmed the positive effect of laser irradiation on velocity and linearity of sperm.

  4. Sperm competition games: the risk model can generate higher sperm allocation to virgin females.

    PubMed

    Ball, M A; Parker, G A

    2007-03-01

    We examine the risk model in sperm competition games for cases where female fertility increases significantly with sperm numbers (sperm limitation). Without sperm competition, sperm allocation increases with sperm limitation. We define 'average risk' as the probability q that females in the population mate twice, and 'perceived risk' as the information males gain about the sperm competition probability with individual females. If males obtain no information from individual females, sperm numbers increase with q unless sperm limitation is high and one of the two competing ejaculates is strongly disfavoured. If males can distinguish between virgin and mated females, greater sperm allocation to virgins is favoured by high sperm limitation, high q, and by the second male's ejaculate being disfavoured. With high sperm limitation, sperm allocation to virgins increases and to mated females decreases with q at high q levels. With perfect information about female mating pattern, sperm allocation (i) to virgins that will mate again exceeds that to mated females and to virgins that will mate only once, (ii) to virgins that mate only once exceeds that for mated females if q is high and there is high second male disadvantage and (iii) to each type of female can decrease with q if sperm limitation is high, although the average allocation increases at least across low q levels. In general, higher sperm allocation to virgins is favoured by: strong disadvantage to the second ejaculate, high sperm limitation, high average risk and increased information (perceived risk). These conditions may apply in a few species, especially spiders. PMID:17305842

  5. Sperm DNA assays and their relationship to sperm motility and morphology in bulls (Bos Taurus).

    PubMed

    Serafini, Rosanna; Romano, Juan E; Varner, Dickson D; Di Palo, Rossella; Love, Charles C

    2015-08-01

    The relationship among sperm DNA assays in bulls with different sperm motility and morphology measures has not been reported. The objectives of the present study were to (1) describe Comet assay measures and examine their repeatability (inter- and intra-assay); (2) compare sperm DNA quality assays (i.e., Sperm Chromatin Structure Assay-SCSA; alkaline and neutral Comet assays and Sperm Bos Halomax assay-SBH) in two groups of bulls selected on either greater and lesser sperm motility and morphology (greater compared with lesser); (3) determine the relationship among DNA assays and sperm motility and morphology values. Inter-assay repeatability was greater for the neutral Comet assay as compared to the alkaline Comet assay. Intra-assay repeatability was greater than inter-assay repeatability for both Comet assays. Comet assay dimension measures and percentage tail DNA were the most repeatable for both Comet assays. Among sperm DNA quality assays, only SCSA measures and neutral Comet assay Ghosts (% Ghosts), head diameter and area, and comet area were different between greater and lesser sperm quality groups (P<0.05). The SCSA measures were inversely correlated with neutral Comet head measures (diameter, area, and intensity) and positively with percentage Ghosts (P<0.05). The % Ghosts and COMP-αt were correlated with some measures of sperm morphology and sperm motility. The neutral Comet assay was more appropriate for sperm evaluation than the alkaline Comet assay for distinguishing among groups with different sperm quality.

  6. The Bull Sperm MicroRNAome and the Effect of Fescue Toxicosis on Sperm MicroRNA Expression

    PubMed Central

    Stowe, Heather M.; Calcatera, Samantha M.; Dimmick, Marcy A.; Andrae, John G.; Duckett, Susan K.; Pratt, Scott L.

    2014-01-01

    Tall fescue [Schedonorus phoenix (Scop.) Holub] accounts for nearly 16 million hectares of pasture in the Southeastern and Mid-Atlantic U.S. due to its heat, drought, and pest resistance, conferred to the plant by its symbiotic relationship with the endophyte Neotyphodium coenophialum. The endophyte produces ergot alkaloids that have negative effects on the growth and reproduction of animals, resulting in the syndrome known as fescue toxicosis. The objectives of our study were to identify microRNA (miRNA) present in bovine sperm and to evaluate the effects of fescue toxicosis on sperm miRNA expression. Angus bulls were assigned to treatments of either toxic or non-toxic fescue seed diets. Semen was collected and subjected to RNA isolation. Three samples from each treatment group were chosen and pooled for deep sequencing. To compare miRNA expression between treatment groups, a microarray was designed and conducted. For each of the top ten expressed miRNA, target prediction analysis was conducted using TargetScan. Gene ontology enrichment was assessed using the Database for Annotation, Visualization and Integrated Discovery. Sequencing results elucidated the presence of 1,582 unique small RNA present in sperm. Of those sequences, 382 were known Bos taurus miRNA, 22 were known but novel to Bos taurus, and 816 were predicted candidate miRNA that did not map to any currently reported miRNA. Of the sequences chosen for microarray, twenty-two showed significant differential expression between treatment groups. Gene pathways of interest included: regulation of transcription, embryonic development (including blastocyst formation), Wnt and Hedgehog signaling, oocyte meiosis, and kinase and phosphatase activity. MicroRNA present in mature sperm appears to not only be left over from spermatogenic processes, but may actually serve important regulatory roles in fertilization and early developmental processes. Further, our results indicate the possibility that environmental

  7. The bull sperm microRNAome and the effect of fescue toxicosis on sperm microRNA expression.

    PubMed

    Stowe, Heather M; Calcatera, Samantha M; Dimmick, Marcy A; Andrae, John G; Duckett, Susan K; Pratt, Scott L

    2014-01-01

    Tall fescue [Schedonorus phoenix (Scop.) Holub] accounts for nearly 16 million hectares of pasture in the Southeastern and Mid-Atlantic U.S. due to its heat, drought, and pest resistance, conferred to the plant by its symbiotic relationship with the endophyte Neotyphodium coenophialum. The endophyte produces ergot alkaloids that have negative effects on the growth and reproduction of animals, resulting in the syndrome known as fescue toxicosis. The objectives of our study were to identify microRNA (miRNA) present in bovine sperm and to evaluate the effects of fescue toxicosis on sperm miRNA expression. Angus bulls were assigned to treatments of either toxic or non-toxic fescue seed diets. Semen was collected and subjected to RNA isolation. Three samples from each treatment group were chosen and pooled for deep sequencing. To compare miRNA expression between treatment groups, a microarray was designed and conducted. For each of the top ten expressed miRNA, target prediction analysis was conducted using TargetScan. Gene ontology enrichment was assessed using the Database for Annotation, Visualization and Integrated Discovery. Sequencing results elucidated the presence of 1,582 unique small RNA present in sperm. Of those sequences, 382 were known Bos taurus miRNA, 22 were known but novel to Bos taurus, and 816 were predicted candidate miRNA that did not map to any currently reported miRNA. Of the sequences chosen for microarray, twenty-two showed significant differential expression between treatment groups. Gene pathways of interest included: regulation of transcription, embryonic development (including blastocyst formation), Wnt and Hedgehog signaling, oocyte meiosis, and kinase and phosphatase activity. MicroRNA present in mature sperm appears to not only be left over from spermatogenic processes, but may actually serve important regulatory roles in fertilization and early developmental processes. Further, our results indicate the possibility that environmental

  8. Intracytoplasmic sperm injection outcomes with cryopreserved testicular sperm aspiration samples.

    PubMed

    Roque, M; Valle, M; Marques, F; Sampaio, M; Geber, S

    2016-04-01

    Intracytoplasmic sperm injection (ICSI) may be performed with testicular frozen-thawed spermatozoa in patients with nonobstructive azoospermia (NOA). Sperm retrieval can be performed in advance of oocyte aspiration, as it may avoid the possibility of no recovery of spermatozoa on the day of oocyte pickup. There are few studies available in the literature concerning the use of frozen-thawed spermatozoa obtained from testicular sperm aspiration (TESA). To evaluate the effects and the outcomes of ICSI with frozen-thawed spermatozoa obtained by TESA, we performed a retrospective analysis of 43 ICSI cycles using frozen-thawed TESA. We obtained acceptable results with a fertilisation rate of 67.9%, an implantation rate (IR) of 17.1%, and clinical and ongoing pregnancy rates of 41.9% and 37.2% respectively. The results of this study suggest that performing ICSI using cryopreserved frozen-thawed testicular spermatozoa with TESA as a first option is a viable, safe, economic and effective method for patients with NOA.

  9. Variability in sperm form and function in the context of sperm competition risk in two Tupinambis lizards

    PubMed Central

    Blengini, Cecilia S; Sergio, Naretto; Gabriela, Cardozo; Giojalas, Laura C; Margarita, Chiaraviglio

    2014-01-01

    In polyandrous species, sperm morphometry and sperm velocity are under strong sexual selection. Although several hypotheses have been proposed to explain the role of sperm competition in sperm trait variation, this aspect is still poorly understood. It has been suggested that an increase in sperm competition pressure could reduce sperm size variation or produce a diversity of sperm to maximize male fertilization success. We aim at elucidating the variability of sperm morphometric traits and velocity in two Tupinambis lizards in the context of sperm competition risk. Sperm traits showed substantial variation at all levels examined: between species, among males within species, and within the ejaculate of individual males. Sperm velocity was found to be positively correlated with flagellum: midpiece ratio, with relatively longer flagella associated with faster sperm. Our results document high variability in sperm form and function in lizards. PMID:25505535

  10. New assays for detection and localization of endogenous lipid peroxidation products in living boar sperm after BTS dilution or after freeze-thawing.

    PubMed

    Brouwers, Jos F; Silva, Patricia F N; Gadella, Barend M

    2005-01-15

    Reactive oxygen species have been implicated in sperm aberrations causing multiple pathologies including sub- and infertility. Freeze/thawing of sperm samples is routinely performed in the cattle breeding industries for semen storage prior to artificial insemination but unusual in porcine breeding industries as semen dilution and storage at 17 degrees C is sufficient for artificial insemination within 2-3 days. However, longer semen storage requires cryopreservation of boar semen. Freeze/thawing procedures induce sperm damage and induce reactive oxygen species in mammalian sperm and boar sperm seems to be more vulnerable for this than bull sperm. We developed a new method to detect reactive oxygen species induced damage at the level of the sperm plasma membrane in bull sperm. Lipid peroxidation in freshly stored and frozen/thawed sperm cells was assessed by mass spectrometric analysis of the main endogenous lipid classes, phosphatidylcholine and cholesterol and by fluorescence techniques using the lipid peroxidation reporter probe C11-BODIPY(581/591). Peroxidation as reported by the fluorescent probe, clearly corresponded with the presence of hydroxy- and hydroperoxyphosphatidylcholine in the sperm membranes, which are early stage products of lipid peroxidation. This allowed us, for the first time, to correlate endogenous lipid peroxidation with localization of this process in the living sperm cells. Cytoplasmatic droplets in incompletely matured sperm cells were intensely peroxidized. Furthermore, lipid peroxidation was particularly strong in the mid-piece and tail of frozen/thawed spermatozoa and significantly less intense in the sperm head. Induction of peroxidation in fresh sperm cells with the lipid soluble reactive oxygen species tert-butylhydroperoxide gave an even more pronounced effect, demonstrating antioxidant activity in the head of fresh sperm cells. Furthermore, we were able to show using the flow cytometer that spontaneous peroxidation was not a

  11. The role of the molecular chaperone heat shock protein A2 (HSPA2) in regulating human sperm-egg recognition.

    PubMed

    Nixon, Brett; Bromfield, Elizabeth G; Dun, Matthew D; Redgrove, Kate A; McLaughlin, Eileen A; Aitken, R John

    2015-01-01

    One of the most common lesions present in the spermatozoa of human infertility patients is an idiopathic failure of sperm-egg recognition. Although this unique cellular interaction can now be readily by-passed by assisted reproductive strategies such as intracytoplasmic sperm injection (ICSI), recent large-scale epidemiological studies have encouraged the cautious use of this technology and highlighted the need for further research into the mechanisms responsible for defective sperm-egg recognition. Previous work in this field has established that the sperm domains responsible for oocyte interaction are formed during spermatogenesis prior to being dynamically modified during epididymal maturation and capacitation in female reproductive tract. While the factors responsible for the regulation of these sequential maturational events are undoubtedly complex, emerging research has identified the molecular chaperone, heat shock protein A2 (HSPA2), as a key regulator of these events in human spermatozoa. HSPA2 is a testis-enriched member of the 70 kDa heat shock protein family that promotes the folding, transport, and assembly of protein complexes and has been positively correlated with in vitro fertilization (IVF) success. Furthermore, reduced expression of HSPA2 from the human sperm proteome leads to an impaired capacity for cumulus matrix dispersal, sperm-egg recognition and fertilization following both IVF and ICSI. In this review, we consider the evidence supporting the role of HSPA2 in sperm function and explore the potential mechanisms by which it is depleted in the spermatozoa of infertile patients. Such information offers novel insights into the molecular mechanisms governing sperm function.

  12. The Beltsville sperm sexing technology: high-speed sperm sorting gives improved sperm output for in vitro fertilization and AI.

    PubMed

    Johnson, L A; Welch, G R; Rens, W

    1999-01-01

    The Beltsville sperm sexing technology is currently the only effective means of altering the sex ratio of offspring in livestock. The method is based on the flow-cytometric separation of X- and Y-chromosome-bearing sperm based on X/Y DNA content difference. It is an effective means of producing progeny of predetermined sex in cattle, swine, sheep, and laboratory animals. The method involves treating sperm with a DNA-binding fluorochrome, Hoechst 33342, and flow-cytometrically sorting them into separate X and Y populations that can subsequently be used for surgical intratubal or intrauterine insemination, deep-uterine insemination, regular artificial insemination in some cases, in vitro fertilization to produce sexed embryos for transfer, and intracytoplasmic sperm injection of ova. Skewed sex ratios of 85 to 95% of one sex or the other have been repeatably achieved in most species. The method has been used worldwide to produce several hundred morphologically normal animal offspring of the predicted sex. It has also been validated in the laboratory using DNA reanalysis of the sorted sperm populations and by fluorescence in situ hybridization and PCR of individual sperm. We developed a new orienting nozzle that we have fitted to both conventional and high-speed cell sorters that have been modified for sperm sorting. Recently we completed the adaptation of the new orienting nozzle to a Cytomation MoFlo high-speed cell sorter modified for sperm. This adaptation of the nozzle has increased the overall production rate of sorted X and Y sperm from about .35 million/h to 5 or 6 million sperm/h (each population). Calves have been born from cows artificially inseminated using conventional technique and sexed sperm. In addition, numerous litters of pigs have been born after transfer of embryos produced from X or Y sorted sperm. PMID:15526798

  13. The reproductive system of Osedax (Annelida, Siboglinidae): ovary structure, sperm ultrastructure, and fertilization mode

    PubMed Central

    Katz, Sigrid; Rouse, Greg W

    2013-01-01

    Osedax is a genus of siboglinid annelids in which the females live on dead vertebrate bones on the seafloor. These females have a posterior end that lies within the bone and contains the ovarian tissue, as well as the “roots” involved with bone degradation and nutrition. The males are microscopic and live as “harems” in the lumen of the gelatinous tube that surrounds the female trunk, well away from the ovary. Females are known to spawn fertilized primary oocytes, suggesting internal fertilization. However, little is known about sperm transfer, sperm storage, or the location of fertilization, and the morphology of the female reproductive system has not been described and compared with the reproductive systems of other siboglinids. A 3D-reconstruction of the ovisac of Osedax showed ovarian tissue with multiple lobes and mature oocytes stored in a “uterus” before being released through the single oviduct. The oviduct emerges as a gonopore on the trunk and travels along the trunk to finally open to the seawater as a thin cylindrical tube among the crown of palps. Light and transmission electron microscopy of mature Osedax sperm revealed elongate heads consisting of a nucleus with helical grooves occupied by mitochondria. In contrast to other Siboglinidae, Osedax sperm are not packaged into spermatophores or spermatozeugmata, and Osedax females lack a discrete region for sperm storage. Transmission electron microscopy and fluorescence microscopy allowed detection of sperm associated with ovarian tissue of the female ovisac of four different Osedax species. This provides the first evidence for the site of internal fertilization in Osedax. A heart body was found in the circulatory system, as seen in other siboglinids and some other annelids. The possible presence of nephridia in the anterior ovisac region was also documented. These morphological features provide new insights for comparing the regionalization of Osedax females in relation to other siboglinids

  14. Ficoll-400 density gradient method as an effective sperm preparation technique for assisted reproductive techniques

    PubMed Central

    Highland, Hyacinth N.; Rishika, A. Sharma; Almira, S. Shaikh; Kanthi, P. Bansal

    2016-01-01

    BACKGROUND: Infertility being a burning issue, the male itself contributes about 40% as a cause, as evident by statistical data. However, Assisted Reproductive Technology (ART) has emerged as a powerful tool in the management of infertility. Sperm preparation techniques govern the selection procedure to separate functional spermatozoa which can then be used in IUI, IVF, and ART and for cryopreservation. AIM: The present study was aimed at evaluation of sperm preparation techniques for reliability, performance and to determine the most effective, feasible and economical technique. MATERIALS AND METHODS: The subjects under study includes males with normal proven fertility (n=40) and the males with unexplained infertility (n=40). Four sperm separation techniques, viz., Swim-up, Swim-down, Sucrose and Ficoll-400 density gradient techniques were evaluated for their efficacy in separation of good quality fraction of spermatozoa. Sperm viability, morphology and maturation status of spermatozoa were taken as evaluation parameters following the standard methods (WHO 2010). STATISTICAL ANALYSIS: Data was analyzed using student's t-test and the four selected techniques were compared with the normal semen samples for scoring the efficiency of the techniques. RESULTS AND DISCUSSION: Out of the several techniques used, Ficoll-400 was found to be more efficient method for separation of spermatozoa. The percentage of change in each parameter was calculated and taken as the index for recovery of potent sperm from the original sperm. Ficoll-400 density gradient yielded higher percentage of live, mature, morphologically normal spermatozoa in an isolated fraction as compared to other three techniques. CONCLUSION: It was observed that a combination of Ficoll-400 gradient separation with Swim-up technique could give quality spermatozoa which in-turn would directly have an impact on the success of IVF and other ART techniques. PMID:27803588

  15. No evidence of trade-offs in the evolution of sperm numbers and sperm size in mammals.

    PubMed

    Tourmente, M; Delbarco Trillo, J; Roldan, E R S

    2015-10-01

    Post-copulatory sexual selection, in the form sperm competition, has influenced the evolution of several male reproductive traits. However, theory predicts that sperm competition would lead to trade-offs between numbers and size of spermatozoa because increased costs per cell would result in a reduction of sperm number if both traits share the same energetic budget. Theoretical models have proposed that, in large animals, increased sperm size would have minimal fitness advantage compared with increased sperm numbers. Thus, sperm numbers would evolve more rapidly than sperm size under sperm competition pressure. We tested in mammals whether sperm competition maximizes sperm numbers and size, and whether there is a trade-off between these traits. Our results showed that sperm competition maximizes sperm numbers in eutherian and metatherian mammals. There was no evidence of a trade-off between sperm numbers and sperm size in any of the two mammalian clades as we did not observe any significant relationship between sperm numbers and sperm size once the effect of sperm competition was taken into account. Maximization of both numbers and size in mammals may occur because each trait is crucial at different stages in sperm's life; for example size-determined sperm velocity is a key determinant of fertilization success. In addition, numbers and size may also be influenced by diverse energetic budgets required at different stages of sperm formation. PMID:26190170

  16. No evidence of trade-offs in the evolution of sperm numbers and sperm size in mammals.

    PubMed

    Tourmente, M; Delbarco Trillo, J; Roldan, E R S

    2015-10-01

    Post-copulatory sexual selection, in the form sperm competition, has influenced the evolution of several male reproductive traits. However, theory predicts that sperm competition would lead to trade-offs between numbers and size of spermatozoa because increased costs per cell would result in a reduction of sperm number if both traits share the same energetic budget. Theoretical models have proposed that, in large animals, increased sperm size would have minimal fitness advantage compared with increased sperm numbers. Thus, sperm numbers would evolve more rapidly than sperm size under sperm competition pressure. We tested in mammals whether sperm competition maximizes sperm numbers and size, and whether there is a trade-off between these traits. Our results showed that sperm competition maximizes sperm numbers in eutherian and metatherian mammals. There was no evidence of a trade-off between sperm numbers and sperm size in any of the two mammalian clades as we did not observe any significant relationship between sperm numbers and sperm size once the effect of sperm competition was taken into account. Maximization of both numbers and size in mammals may occur because each trait is crucial at different stages in sperm's life; for example size-determined sperm velocity is a key determinant of fertilization success. In addition, numbers and size may also be influenced by diverse energetic budgets required at different stages of sperm formation.

  17. Nuclear microscopy of sperm cell elemental structure

    NASA Astrophysics Data System (ADS)

    Bench, Graham S.; Balhorn, Rod; Friz, Alexander M.

    1995-05-01

    Theories suggest there is a link between protamine concentrations in individual sperm and male fertility. Previously, biochemical analyses have used pooled samples containing millions of sperm to determine protamine concentrations. These methods have not been able to determine what percentage of morphologically normal sperm are biochemically defective and potentially infertile. Nuclear microscopy has been utilized to measure elemental profiles at the single sperm level. By measuring the amount of phosphorus and sulfur, the total DNA and protamine content in individual sperm from fertile bull and mouse semen have been determined. These values agree with results obtained from other biochemical analyses. Nuclear microscopy shows promise for measuring elemental profiles in the chromatin of individual sperm. The technique may be able to resolve theories regarding the importance of protamines to male fertility and identify biochemical defects responsible for certain types of male infertility.

  18. Nuclear microscopy of sperm cell elemental structure

    SciTech Connect

    Bench, G.S.; Balhorn, R.; Friz, A.M.; Freeman, S.P.H.T.

    1994-09-28

    Theories suggest there is a link between protamine concentrations in individual sperm and male fertility. Previously, biochemical analyses have used pooled samples containing millions of sperm to determine protamine concentrations. These methods have not been able to determine what percentage of morphologically normal sperm are biochemically defective and potentially infertile. Nuclear microscopy has been utilized to measure elemental profiles at the single sperm level. By measuring the amount of phosphorus and sulfur, the total DNA and protamine content in individual sperm from fertile bull and mouse semen have been determined. These values agree with results obtained from other biochemical analyses. Nuclear microscopy shows promise for measuring elemental profiles in the chromatin of individual sperm. The technique may be able to resolve theories regarding the importance of protamines to male fertility and identify biochemical defects responsible for certain types of male infertility.

  19. Sperm protamine-status correlates to the fertility of breeding bulls.

    PubMed

    Dogan, Sule; Vargovic, Peter; Oliveira, Rodrigo; Belser, Lauren E; Kaya, Abdullah; Moura, Arlindo; Sutovsky, Peter; Parrish, John; Topper, Einko; Memili, Erdoğan

    2015-04-01

    During fertilization, spermatozoa make essential contributions to embryo development by providing oocyte activating factors, centrosomal components, and paternal chromosomes. Protamines are essential for proper packaging of sperm DNA; however, in contrast to the studies of oocyte-related female infertility, the influence of sperm chromatin structure on male infertility has not been evaluated extensively. The objective of this study was to determine the sperm chromatin content of bull spermatozoa by evaluating DNA fragmentation, chromatin maturity/protamination, PRM1 protein status, and nuclear shape in spermatozoa from bulls with different fertility. Relationships between protamine 1 (PRM1) and the chromatin integrity were ascertained in spermatozoa from Holstein bulls with varied (high vs. low) but acceptable fertility. Sperm DNA fragmentation and chromatin maturity (protamination) were tested using Halomax assay and toluidine blue staining, respectively. The PRM1 content was assayed using Western blotting and in-gel densitometry, flow cytometry, and immunocytochemistry. Fragmentation of DNA was increased and chromatin maturity significantly reduced in spermatozoa from low-fertility bulls compared to those from high-fertility bulls. Field fertility scores of the bulls were negatively correlated with the percentage of spermatozoa displaying reduced protamination and fragmented DNA using toluidine blue and Halomax, respectively. Bull fertility was also positively correlated with PRM1 content by Western blotting and flow cytometry. However, detection of PRM1 content by Western blotting alone was not predictive of bull fertility. In immunocytochemistry, abnormal spermatozoa showed either a lack of PRM1 or scattered localization in the apical/acrosomal region of the nuclei. The nuclear shape was distorted in spermatozoa from low-fertility bulls. In conclusion, we showed that inadequate amount and localization of PRM1 were associated with defects in sperm chromatin

  20. Movement of sea urchin sperm flagella.

    PubMed

    Rikmenspoel, R

    1978-02-01

    The motion of the sea urchin sperm flagellum was analyzed from high-speed cinemicrographs. At all locations on the flagellum the transversal motion and the curvature were found to vary sinusoidally in time. The curvatures of the flagella increase strongly near the proximal junction. Two sperm are described in transient from rest to normal motion. The full wave motion developed in both sperm within 40 ms.

  1. Post-mortem sperm retrieval in Australasia.

    PubMed

    Kroon, Benjamin; Kroon, Frederick; Holt, Saul; Wong, Brittany; Yazdani, Anusch

    2012-10-01

    Post-mortem Sperm Retrieval (PMSR) is seldom requested in Australasia. The retrieval of sperm is permitted only by prior written consent or by order of the court. Sperm should be retrieved within 24 h following death; however, collection within 36 h may still be successful. The clinical response to such a request must be mindful of complex ethical and legal considerations. Clear, accessible and consistent law in this area would benefit medical, legal and societal stakeholders. PMID:22862141

  2. Diazinon alters sperm chromatin structure in mice by phosphorylating nuclear protamines

    SciTech Connect

    Pina-Guzman, B.; Solis-Heredia, M.J.; Quintanilla-Vega, B. . E-mail: mquintan@mail.cinvestav.mx

    2005-01-15

    Organophosphorus (OP) pesticides, widely used in agriculture and pest control, are associated with male reproductive effects, including sperm chromatin alterations, but the mechanisms underlying these effects are unknown. The main toxic action of OP is related to phosphorylation of proteins. Chemical alterations in sperm nuclear proteins (protamines), which pack DNA during the last steps of spermatogenesis, contribute to male reproductive toxicity. Therefore, in the present study, we tested the ability of diazinon (DZN), an OP compound, to alter sperm chromatin by phosphorylating nuclear protamines. Mice were injected with a single dose of DZN (8.12 mg/kg, i.p.), and killed 8 and 15 days after treatment. Quality of sperm from epididymis and vas deferens was evaluated through standard methods and chromatin condensation by flow cytometry (DNA Fragmented Index parameters: DFI and DFI%) and fluorescence microscopy using chromomycin-A{sub 3} (CMA{sub 3}). Increases in DFI (15%), DFI% (4.5-fold), and CMA{sub 3} (2-fold) were observed only at 8 days post-treatment, indicating an alteration in sperm chromatin condensation and DNA damage during late spermatid differentiation. In addition, an increase of phosphorous content (approximately 50%) in protamines, especially in the phosphoserine content (approximately 73%), was found at 8 days post-treatment. Sperm viability, motility, and morphology showed significant alterations at this time. These data strongly suggest that spermatozoa exposed during the late steps of maturation were the targets of DZN exposure. The correlation observed between the phosphorous content in nuclear protamines with DFI%, DFI, and CMA{sub 3} provides evidence that phosphorylation of nuclear protamines is involved in the OP effects on sperm chromatin.

  3. 21 CFR 173.275 - Hydrogenated sperm oil.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... from rendering the fatty tissue of the sperm whale or is prepared by synthesis of fatty acids and fatty alcohols derived from the sperm whale. The sperm oil obtained by rendering is refined. The oil...

  4. Bovine binder-of-sperm protein BSP1 promotes protrusion and nanotube formation from liposomes

    SciTech Connect

    Lafleur, Michel; Courtemanche, Lesley; Karlsson, Goeran; Edwards, Katarina; Schwartz, Jean-Louis; Manjunath, Puttaswamy

    2010-08-27

    Research highlights: {yields} Binder-of-sperm protein 1 (BSP1) modifies the morphology of lipidic vesicles inducing bead necklace-like and thread-like structures. {yields} In the presence of multilamellar liposomes, BSP1 leads to the formation of long nanotubes. {yields} The insertion of BSP1 in the external lipid leaflet of membranes induces local changes in bilayer curvature. -- Abstract: Binder-of-sperm (BSP) proteins interact with sperm membranes and are proposed to extract selectively phosphatidylcholine and cholesterol from these. This change in lipid composition is a key step in sperm capacitation. The present work demonstrates that the interactions between the protein BSP1 and model membranes composed with phosphatidylcholine lead to drastic changes in the morphology of the lipidic self-assemblies. Using cryo-electron microscopy and fluorescence microscopy, we show that, in the presence of the protein, the lipid vesicles elongate, and form bead necklace-like structures that evolve toward small vesicles or thread-like structures. In the presence of multilamellar vesicles, where a large reservoir of lipid is available, the presence of BSP proteins lead to the formation of long nanotubes. Long spiral-like threads, associated with lipid/protein complexes, are also observed. The local curvature of lipid membranes induced by the BSP proteins may be involved in lipid domain formation and the extraction of some lipids during the sperm maturation process.

  5. Male and female effects on sperm precedence in the giant sperm species Drosophila bifurca.

    PubMed

    Luck, Nathalie; Dejonghe, Béatrice; Fruchard, Stéphane; Huguenin, Sophie; Joly, Dominique

    2007-07-01

    Sperm competition is expected to be a driving force in sexual selection. In internally fertilized organisms, it occurs when ejaculates from more than one male are present simultaneously within the female's reproductive tract. It has been suggested that greater sperm size may improve the competitive ability of sperm, but studies provide contradictory results depending on the species. More recently, the role of females in the evolution of sperm morphology has been pointed out. We investigate here the male and female effects that influence sperm precedence in the giant sperm species, Drosophila bifurca Patterson & Wheeler. Females were mated with two successive males, and the paternity outcomes for both males were analyzed after determining sperm transfer and storage. We found very high values of last male sperm precedence, suggesting a strong interaction between rival sperm. However, the data also indicate high frequencies of removal of the sperm of the first male from the female reproductive tract prior to any interaction with the second male. This implies that successful paternity depends mainly on successful sperm storage. Knowing what happens to the sperm within females appears to be a prerequisite for disentangling post-copulatory sexual interactions between males and females.

  6. Autoradiographic visualization of the mouse egg's sperm receptor bound to sperm

    SciTech Connect

    Bleil, J.D.; Wassarman, P.M.

    1986-04-01

    The extracellular coat, or zona pellucida, of mammalian eggs contains species-specific receptors to which sperm bind as a prelude to fertilization. In mice, ZP3, one of only three zona pellucida glycoproteins, serves as sperm receptor. Acrosome-intact, but not acrosome-reacted, mouse sperm recognize and interact with specific O-linked oligosaccharides of ZP3 resulting in sperm-egg binding. Binding, in turn, causes sperm to undergo the acrosome reaction; a membrane fusion event that results in loss of plasma membrane at the anterior region of the head and exposure of inner acrosomal membrane with its associated acrosomal contents. Bound, acrosome-reacted sperm are able to penetrate the zona pellucida and fuse with the egg's plasma membrane (fertilization). In the present report, we examined binding of radioiodinated, purified, egg ZP3 to both acrosome intact and acrosome reacted sperm by whole-mount autoradiography. Silver grains due to bound 125I-ZP3 were found localized to the acrosomal cap region of heads of acrosome-reacted sperm. Under the same conditions, 125I-fetuin bound at only background levels to heads of both acrosome-intact and -reacted sperm, and 125I-ZP2, another zona pellucida glycoprotein, bound preferentially to acrosome-reacted sperm. These results provide visual evidence that ZP3 binds preferentially and specifically to heads of acrosome intact sperm; properties expected of the mouse egg's sperm receptor.

  7. Artificial insemination with donor sperm (AID): heterogeneity in sperm banking facilities in a single country (Belgium).

    PubMed

    Thijssen, A; Dhont, N; Vandormael, E; Cox, A; Klerkx, E; Creemers, E; Ombelet, W

    2014-01-01

    Due to the high inflow of foreign patients seeking cross-border reproductive care in Belgium and the increased number of lesbian couples and single women who call for artificial insemination with donor sperm (AID), Belgian sperm banks nowadays face a shortage in donor sperm. However, since there is no central registration system for sperm donors in Belgium, no figures are currently available supporting this statement. Therefore a study was performed to obtain a detailed overview of the sperm banking facilities in Belgium. Questionnaires were sent to all Belgian centres for assisted reproduction with laboratory facilities (n = 18) to report on their sperm banking methods. The results showed that 82% of the centres rely partially or completely on foreign donor sperm. Moreover, four of the thirteen centres that have their own sperm bank use imported donor sperm in > 95% AID cycles. Our results show that in 63% of the Belgian AID cycles imported Danish donor sperm is being used. Donor recruitment is mainly performed through the centre's website (61%) or by distributing flyers in the centre (46%) and 9 to 180 potential donors have been recruited per centre in 2013. Eventually, 15 to 50% of these candidate donors were accepted. Different criteria for donor acceptance are handled by the centres: donor age limits range from 18-25 to 36-46 years old, and thresholds for sperm normality differ considerably. We can conclude that a wide variation in methods associated with sperm banking is observed in Belgian centres.

  8. At the physical limit - chemosensation in sperm.

    PubMed

    Strünker, T; Alvarez, L; Kaupp, U B

    2015-10-01

    Many cells probe their environment for chemical cues. Some cells respond to picomolar concentrations of neuropeptides, hormones, pheromones, or chemoattractants. At such low concentrations, cells encounter only a few molecules. The mechanistic underpinnings of single-molecule sensitivity are not known for any eukaryotic cell. Sea urchin sperm offer a unique model to unveil in quantitative terms the principles underlying chemosensation at the physical limit. Here, we discuss the mechanisms of such exquisite sensitivity and the computational operations performed by sperm during chemotactic steering. Moreover, we highlight commonalities and differences between signalling in sperm and photoreceptors and among sperm from different species. PMID:25768273

  9. Kobe earthquake and reduced sperm motility.

    PubMed

    Fukuda, M; Fukuda, K; Shimizu, T; Yomura, W; Shimizu, S

    1996-06-01

    We investigated a possible relationship between the Kobe earthquake (January 17, 1995) and the quality of semen. We assessed sperm concentration and motility of 27 male patients who had a concentration of more than 30 million/ml and >40% sperm motility within 5 months before the earthquake. Twelve male patients from districts with a magnitude of <4 on the Richter scale showed no difference in sperm concentration and motility before and after the earthquake. Of 15 male patients from districts with a magnitude of >6, five patients whose houses received no damage showed no distinct changes in sperm concentration and motility. In contrast, 10 patients whose houses were partially or completely destroyed showed significantly (P < 0.001) lower sperm motility after the earthquake than before, although no significant difference of sperm concentration could be observed. Of these latter 10 patients, seven could be followed. In six patients, sperm motility was restored between 2 and 9 months after the earthquake; the sperm motility in one patient, whose father died a victim of the house crash, has not yet recovered. Thus, the acute stress resulting from such a catastrophic earthquake could be a possible cause of reduced sperm motility.

  10. Chicken sperm transcriptome profiling by microarray analysis.

    PubMed

    Singh, R P; Shafeeque, C M; Sharma, S K; Singh, R; Mohan, J; Sastry, K V H; Saxena, V K; Azeez, P A

    2016-03-01

    It has been confirmed that mammalian sperm contain thousands of functional RNAs, and some of them have vital roles in fertilization and early embryonic development. Therefore, we attempted to characterize transcriptome of the sperm of fertile chickens using microarray analysis. Spermatozoal RNA was pooled from 10 fertile males and used for RNA preparation. Prior to performing the microarray, RNA quality was assessed using a bioanalyzer, and gDNA and somatic cell RNA contamination was assessed by CD4 and PTPRC gene amplification. The chicken sperm transcriptome was cross-examined by analysing sperm and testes RNA on a 4 × 44K chicken array, and results were verified by RT-PCR. Microarray analysis identified 21,639 predominantly nuclear-encoded transcripts in chicken sperm. The majority (66.55%) of the sperm transcripts were shared with the testes, while surprisingly, 33.45% transcripts were detected (raw signal intensity greater than 50) only in the sperm and not in the testes. The greatest proportion of up-regulated transcripts were responsible for signal transduction (63.20%) followed by embryonic development (56.76%) and cell structure (56.25%). Of the 20 most abundant transcripts, 18 remain uncharacterized, whereas the least abundant genes were mostly associated with the ribosome. These findings lay a foundation for more detailed investigations on sperm RNAs in chickens to identify sperm-based biomarkers for fertility.

  11. Role of arachidonic acid cascade in Rhinella arenarum oocyte maturation.

    PubMed

    Ortiz, Maria Eugenia; Arias-Torres, Ana Josefina; Zelarayán, Liliana Isabel

    2015-08-01

    There are no studies that document the production of prostaglandins (PGs) or their role in Rhinella arenarum oocyte maturation. In this study, we analysed the effect of arachidonic acid (AA) and prostaglandins (PGs) on maturation, activation and pronuclear formation in R. arenarum oocytes. Our results demonstrated that AA was capable of inducing maturation in time-dependent and dose-dependent manner. Arachidonic acid-induced maturation was inhibited by indomethacin. PGs from AA hydrolysis, such as prostaglandin F2α (PGF2α) and, to a lesser extent, PGE2, induced meiosis resumption. Oocyte maturation in response to PGF2α was similar to that produced by progesterone (P4). Oocyte response to PGE1 was scarce. Rhinella arenarum oocyte PGF2α-induced maturation showed seasonal variation. From February to June, oocytes presented low sensitivity to PGF2α. In following periods, this response increased until a maximum was reached during October to January, a close temporal correlation with oocyte response to P4 being observed. The effect of PGF2α on maturation was verified by analysing the capacity of oocytes to activate and form pronuclei after being injected with homologous sperm. The cytological analysis of activated oocytes demonstrated the absence of cortical granules in oocytes, suggesting that PGF2α induces germinal vesicle breakdown (GVBD) and meiosis resumption up to metaphase II. In turn, oocytes matured by the action of PGF2α were able to form pronuclei after fertilization in a similar way to oocyte maturated by P4. In microinjection of mature cytoplasm experiments, the transformation of pre-maturation promoting factor (pre-MPF) to MPF was observed when oocytes were treated with PGF2α. In summary, our results illustrated the participation of the AA cascade and its metabolites in maturation, activation and pronuclei formation in R. arenarum. PMID:24964276

  12. Alterations to the bull sperm surface proteins that bind sperm to oviductal epithelium.

    PubMed

    Hung, Pei-hsuan; Suarez, Susan S

    2012-10-01

    Three Binder of SPerm proteins (BSP1, BSP3, BSP5) are secreted by bovine seminal vesicles into seminal plasma and adsorbed onto sperm. When sperm inseminated into the female reach the oviduct, the BSP proteins bind them to its epithelial lining, forming a sperm storage reservoir. Previously, we reported that binding of capacitated sperm to oviductal epithelium in vitro is lower than that of uncapacitated sperm and we proposed that reduced binding was due to loss of BSP proteins during capacitation. Because of differences in amino acid sequences, we predicted that each BSP would respond differently to capacitating conditions. To test whether all three BSP proteins were lost from sperm during capacitation and whether the kinetics of loss differed among the three BSP proteins, ejaculated bull sperm were incubated under various capacitating conditions, and then the amounts of BSP proteins remaining on the sperm were assayed by Western blotting. Capacitation was assayed by analysis of protein tyrosine phosphorylation. While loss of BSP1 was not detected, most of the BSP5 was lost from sperm during incubation in TALP medium, even without addition of the capacitation enhancers heparin and dbcAMP-IBMX. Surprisingly, a smaller molecular mass was detected by anti-BSP3 antibodies in extracts of incubated sperm. Its identity was confirmed as BSP3 by mass spectrometry, indicating that BSP3 undergoes modification on the sperm surface. These changes in the composition of BSP proteins on sperm could play a role in releasing sperm from the storage reservoir by modifying sperm interactions with the oviductal epithelium.

  13. Sexual behavior and seminal characteristics of fertile mature New Zealand White male rabbits of different body weights.

    PubMed

    Rodríguez-De Lara, R; Fallas-López, M; García-Muñiz, J G; Martínez-Hernández, P A; Rangel-Santos, R; Maldonado-Siman, E; Cadena-Meneses, J A

    2015-01-01

    Body weight in different mammalian species influences reproductive potential. The aim of the present study was to determine the relationship of body weight at the time of semen collection with libido, seminal characteristics and number of semen doses for artificial insemination (AI) in New Zealand White mature fertile male rabbits. Data came from 728 semen collections of 14 rabbits, 15-months of age that were sexually experienced with proven semen quality and fertility. Semen collection was performed twice a week with two ejaculates at each collection time and lasted 14 weeks. A second ejaculation was collected at 1-2h after the first. Data from each male from first and second ejaculates from 1 day of semen collection throughout the trial were averaged (n=324) and partial correlation coefficients and regression equations were estimated to describe the relationship of male body weight to ejaculation reaction time and 12 semen and sperm characteristics. As body weight increased there was a linear (P<0.05) increase in reaction time, abnormal sperm with an intact membrane and abnormal sperm with a damaged membrane and a linear (P<0.05) decrease in semen volume, sperm concentration per ejaculate, normal sperm with an intact membrane, number of normal motile sperm with an intact membrane and suitable semen doses for AI. Body weight of the mature male rabbit at semen collection had some influence on libido, semen and sperm characteristics, with a general trend toward a lesser reproduction potential as body weight increases. PMID:25482591

  14. Sexual behavior and seminal characteristics of fertile mature New Zealand White male rabbits of different body weights.

    PubMed

    Rodríguez-De Lara, R; Fallas-López, M; García-Muñiz, J G; Martínez-Hernández, P A; Rangel-Santos, R; Maldonado-Siman, E; Cadena-Meneses, J A

    2015-01-01

    Body weight in different mammalian species influences reproductive potential. The aim of the present study was to determine the relationship of body weight at the time of semen collection with libido, seminal characteristics and number of semen doses for artificial insemination (AI) in New Zealand White mature fertile male rabbits. Data came from 728 semen collections of 14 rabbits, 15-months of age that were sexually experienced with proven semen quality and fertility. Semen collection was performed twice a week with two ejaculates at each collection time and lasted 14 weeks. A second ejaculation was collected at 1-2h after the first. Data from each male from first and second ejaculates from 1 day of semen collection throughout the trial were averaged (n=324) and partial correlation coefficients and regression equations were estimated to describe the relationship of male body weight to ejaculation reaction time and 12 semen and sperm characteristics. As body weight increased there was a linear (P<0.05) increase in reaction time, abnormal sperm with an intact membrane and abnormal sperm with a damaged membrane and a linear (P<0.05) decrease in semen volume, sperm concentration per ejaculate, normal sperm with an intact membrane, number of normal motile sperm with an intact membrane and suitable semen doses for AI. Body weight of the mature male rabbit at semen collection had some influence on libido, semen and sperm characteristics, with a general trend toward a lesser reproduction potential as body weight increases.

  15. Sexual selection and the evolution of sperm quality.

    PubMed

    Fitzpatrick, John L; Lüpold, Stefan

    2014-12-01

    Sperm experience intense and varied selection that dramatically impacts the evolution of sperm quality. Selection acts to ensure that sperm are fertilization-competent and able to overcome the many challenges experienced on their way towards eggs. However, simply being able to fertilize an egg is not enough to ensure male fertility in most species. Owing to the prevalence of female multiple mating throughout the animal kingdom, successful fertilization requires sperm to outcompete rival sperm. In addition, females can actively influence sperm quality, storage or utilization to influence male fertility. This review provides an overview of how these selective forces influence the evolution of sperm quality. After exploring the link between sperm traits and male fertility, we examine how post-mating competition between rival ejaculates influences the evolution of sperm quality. We then describe how complex genetic, social and sexual interactions influence sperm quality, focusing on the importance of seminal fluid and interactions between sperm and the female's reproductive tract. In light of the complexities of selection on sperm traits, greater use of multivariate approaches that incorporate male-male, sperm-sperm and sperm-female interactions to study sperm quality will enhance our understanding of how selection acts on sperm traits and factors influencing male fertility. Because the metric of male reproductive success--fertilization--is the same across the animal kingdom, we argue that information about sperm evolution gained from non-human animals has enormous potential to further our understanding of the factors that impact human fertility.

  16. Impact of spontaneous smoking cessation on sperm quality: case report.

    PubMed

    Santos, E Prentki; López-Costa, S; Chenlo, P; Pugliese, M N; Curi, S; Ariagno, J; Repetto, H; Sardi, M; Palaoro, L; Mendeluk, G

    2011-12-01

    We evaluated sperm quality after a 3-month smoking cessation programme by sperm analysis, objective sperm motility analysis, protein tyrosine phosphorylation in capacitating conditions and DNA fragmentation (TUNEL). Sperm analysis after smoking cessation revealed a distinctive improvement in sperm concentration, fast spermatozoa (≥35 μm/s), sperm vitality, percentage of spermatozoa recuperated after an enrichment technique and protein tyrosine phosphorylation. However, no changes were observed in the number of germinal cells in the ejaculate, sperm morphology and sperm DNA fragmentation. It is concluded that physicians should strongly advise their patients to quit smoking before undergoing medical treatment or assisted reproduction techniques to achieve pregnancy.

  17. ATPases, ion exchangers and human sperm motility.

    PubMed

    Peralta-Arias, Rubén D; Vívenes, Carmen Y; Camejo, María I; Piñero, Sandy; Proverbio, Teresa; Martínez, Elizabeth; Marín, Reinaldo; Proverbio, Fulgencio

    2015-05-01

    Human sperm has several mechanisms to control its ionic milieu, such as the Na,K-ATPase (NKA), the Ca-ATPase of the plasma membrane (PMCA), the Na(+)/Ca(2) (+)-exchanger (NCX) and the Na(+)/H(+)-exchanger (NHE). On the other hand, the dynein-ATPase is the intracellular motor for sperm motility. In this work, we evaluated NKA, PMCA, NHE, NCX and dynein-ATPase activities in human sperm and investigated their correlation with sperm motility. Sperm motility was measured by Computer Assisted Semen Analysis. It was found that the NKA activity is inhibited by ouabain with two Ki (7.9 × 10(-9) and 9.8 × 10(-5) M), which is consistent with the presence of two isoforms of α subunit of the NKA in the sperm plasma membranes (α1 and α4), being α4 more sensitive to ouabain. The decrease in NKA activity is associated with a reduction in sperm motility. In addition, sperm motility was evaluated in the presence of known inhibitors of NHE, PMCA and NCX, such as amiloride, eosin, and KB-R7943, respectively, as well as in the presence of nigericin after incubation with ouabain. Amiloride, eosin and KB-R7943 significantly reduced sperm motility. Nigericin reversed the effect of ouabain and amiloride on sperm motility. Dynein-ATPase activity was inhibited by acidic pH and micromolar concentrations of Ca(2) (+). We explain our results in terms of inhibition of the dynein-ATPase in the presence of higher cytosolic H(+) and Ca(2) (+), and therefore inhibition of sperm motility. PMID:25820902

  18. Laminin-111 Inhibits Bovine Fertilization but Improves Embryonic Development in vitro, and Receptor Integrin-β1 is Involved in Sperm-Oocyte Binding.

    PubMed

    Lin, F; Huang, C-J; Liu, C-S; Guo, L-L; Liu, G; Liu, H-J

    2016-10-01

    This study detected the distribution of laminin during embryonic formation by immunofluorescence. To determine the possible function of laminin on developmental ability of in vitro fertilized embryos, the presumptive zygotes were divided and transferred to CR1aa medium supplemented with different concentrations (0 μg/ml, 5 μg/ml, 10 μg/ml and 20 μg/ml) of laminin. To explore the association with sperm-oocyte fusion, oocytes and/or sperm were pre-incubated with laminin or anti-β1 antibody before insemination. Laminin was absent in mature oocytes and could be detected first at the 8-cell stage and then displayed an increasing tendency. Adding 10 μg/ml laminin to the culture medium improved embryonic development including cleavage rate, blastocyst rate, total cell numbers in the blastocyst and cell numbers in the inner cell mass. Laminin inhibited sperm-oocyte fusion when incubated with oocytes and/or sperm before in vitro fertilization, and only integrin-β1 of sperm was involved in sperm-oocyte binding. Inhibition may be caused by blocking β1, but why laminin inhibits fertilization is still unknown. The results suggest that laminin plays an important role during embryonic formation and has a negative function in sperm-oocyte fusion, but improves embryonic development. However, only integrin-β1 is involved in sperm-oocyte binding. PMID:27491353

  19. Dynamics of vegetative cytoplasm during generative cell formation and pollen maturation in Arabidopsis thaliana

    NASA Technical Reports Server (NTRS)

    Kuang, A.; Musgrave, M. E.

    1996-01-01

    Ultrastructural changes of pollen cytoplasm during generative cell formation and pollen maturation in Arabidopsis thaliana were studied. The pollen cytoplasm develops a complicated ultrastructure and changes dramatically during these stages. Lipid droplets increase after generative cell formation and their organization and distribution change with the developmental stage. Starch grains in amyloplasts increase in number and size during generative and sperm cell formation and decrease at pollen maturity. The shape and membrane system of mitochondria change only slightly. Dictyosomes become very prominent, and numerous associated vesicles are observed during and after sperm cell formation. Endoplasmic reticulum appears extensively as stacks during sperm cell formation. Free and polyribosomes are abundant in the cytoplasm at all developmental stages although they appear denser at certain stages and in some areas. In mature pollen, all organelles are randomly distributed throughout the vegetative cytoplasm and numerous small particles appear. Organization and distribution of storage substances and appearance of these small particles during generative and sperm cell formation and pollen maturation are discussed.

  20. Panning for sperm gold: Isolation and purification of apyrene and eupyrene sperm from lepidopterans.

    PubMed

    Karr, Timothy L; Walters, James R

    2015-08-01

    We describe a simple and straightforward procedure for the purification and separation of apyrene and eupyrene forms of lepidopteran sperm. The procedure is generally applicable to both butterfly and moth species with results varying according to the relative amounts of sperm produced and size of sperm storage organs. The technique relies upon inherent differences between eupyene sperm bundles and free apyrene sperm morphology. These differences allow for separation of the sperm morphs by repeated "panning" of sperm bundles into the center of a plastic dish. The purified eupyrene sperm bundles can then be removed and apyrene sperm collected from the supernatant by centrifugation. Efficacy of the purification process was confirmed by light microscopy and gel electrophoresis of the resulting fractions. Both one- and two-dimensional gel electrophoresis identified significant protein differences between the fractions further suggesting that the panning procedure effectively separated eurpyrene from apyrene sperm. The panning procedure should provide a convenient and accessible technique for further studies of sperm biology in lepidopterans.

  1. Sperm Dynamics in Spiders (Araneae): Ultrastructural Analysis of the Sperm Activation Process in the Garden Spider Argiope bruennichi (Scopoli, 1772)

    PubMed Central

    Vöcking, Oliver; Uhl, Gabriele; Michalik, Peter

    2013-01-01

    Storage of sperm inside the female genital tract is an integral phase of reproduction in many animal species. The sperm storage site constitutes the arena for sperm activation, sperm competition and female sperm choice. Consequently, to understand animal mating systems information on the processes that occur from sperm transfer to fertilization is required. Here, we focus on sperm activation in spiders. Male spiders produce sperm whose cell components are coiled within the sperm cell and that are surrounded by a proteinaceous sheath. These inactive and encapsulated sperm are transferred to the female spermathecae where they are stored for later fertilization. We analyzed the ultrastructural changes of sperm cells during residency time in the female genital system of the orb-web spider Argiope bruennichi. We found three clearly distinguishable sperm conditions: encapsulated sperm (secretion sheath present), decapsulated (secretion sheath absent) and uncoiled sperm (cell components uncoiled, presumably activated). After insemination, sperm remain in the encapsulated condition for several days and become decapsulated after variable periods of time. A variable portion of the decapsulated sperm transforms rapidly to the uncoiled condition resulting in a simultaneous occurrence of decapsulated and uncoiled sperm. After oviposition, only decapsulated and uncoiled sperm are left in the spermathecae, strongly suggesting that the activation process is not reversible. Furthermore, we found four different types of secretion in the spermathecae which might play a role in the decapsulation and activation process. PMID:24039790

  2. Sperm dynamics in spiders (Araneae): ultrastructural analysis of the sperm activation process in the garden spider Argiope bruennichi (Scopoli, 1772).

    PubMed

    Vöcking, Oliver; Uhl, Gabriele; Michalik, Peter

    2013-01-01

    Storage of sperm inside the female genital tract is an integral phase of reproduction in many animal species. The sperm storage site constitutes the arena for sperm activation, sperm competition and female sperm choice. Consequently, to understand animal mating systems information on the processes that occur from sperm transfer to fertilization is required. Here, we focus on sperm activation in spiders. Male spiders produce sperm whose cell components are coiled within the sperm cell and that are surrounded by a proteinaceous sheath. These inactive and encapsulated sperm are transferred to the female spermathecae where they are stored for later fertilization. We analyzed the ultrastructural changes of sperm cells during residency time in the female genital system of the orb-web spider Argiope bruennichi. We found three clearly distinguishable sperm conditions: encapsulated sperm (secretion sheath present), decapsulated (secretion sheath absent) and uncoiled sperm (cell components uncoiled, presumably activated). After insemination, sperm remain in the encapsulated condition for several days and become decapsulated after variable periods of time. A variable portion of the decapsulated sperm transforms rapidly to the uncoiled condition resulting in a simultaneous occurrence of decapsulated and uncoiled sperm. After oviposition, only decapsulated and uncoiled sperm are left in the spermathecae, strongly suggesting that the activation process is not reversible. Furthermore, we found four different types of secretion in the spermathecae which might play a role in the decapsulation and activation process.

  3. Methamidophos alters sperm function and DNA at different stages of spermatogenesis in mice

    SciTech Connect

    Urióstegui-Acosta, Mayrut; Hernández-Ochoa, Isabel; Sánchez-Gutiérrez, Manuel; Piña-Guzmán, Belem; Rafael-Vázquez, Leticia; Solís-Heredia, M.J.; Martínez-Aguilar, Gerardo; Quintanilla-Vega, Betzabet

    2014-09-15

    Methamidophos (MET) is a highly toxic organophosphate (OP) pesticide that is widely used in developing countries. MET has male reproductive effects, including decreased fertility. We evaluated MET effects on sperm quality, fertilization and DNA integrity, exploring the sensitivity of different stages of spermatogenesis. Adult male mice received MET (3.75 or 5 mg/kg-bw/ip/day/4 days) and were euthanized 1, 28 or 45 days post-treatment (dpt) to evaluate MET's effects on epididymal maturation, meiosis or mitosis, respectively. Spermatozoa were obtained from the cauda epididymis–vas deferens and were evaluated for sperm quality, acrosome reaction (AR; Coomassie staining), mitochondrial membrane potential (by JC-1), DNA damage (comet assay), oxidative damage (malondialdehyde (MDA) production), in vitro fertilization and protein phosphorylation (immunodetection), and erythrocyte acetylcholinesterase (AChE) activity. At 1-dpt, MET inhibited AChE (43–57%) and increased abnormal cells (6%). While at 28- and 45-dpt, sperm motility and viability were significantly reduced with an increasing MET dose, and abnormal morphology increased at 5 mg/kg/day/4 days. MDA and mitochondrial activity were not affected at any dose or time. DNA damage (OTM and %DNA) was observed at 5 mg/kg/day/4 days in a time-dependent manner, whereas both parameters were altered in cells from mice exposed to 3.75 mg/kg/day/4 days only at 28-dpt. Depending on the time of collection, initial-, spontaneous- and induced-AR were altered at 5 mg/kg/day/4 days, and the fertilization capacity also decreased. Sperm phosphorylation (at serine and tyrosine residues) was observed at all time points. Data suggest that meiosis and mitosis are the more sensitive stages of spermatogenesis for MET reproductive toxicity compared to epididymal maturation. - Highlights: • Methamidophos alters sperm cell function at different stages of spermatogenesis. • Testicular stages of spermatogenesis are more sensitive to

  4. Investigation on the Origin of Sperm DNA Fragmentation: Role of Apoptosis, Immaturity and Oxidative Stress

    PubMed Central

    Muratori, Monica; Tamburrino, Lara; Marchiani, Sara; Cambi, Marta; Olivito, Biagio; Azzari, Chiara; Forti, Gianni; Baldi, Elisabetta

    2015-01-01

    Sperm DNA fragmentation (sDF) represents a threat to male fertility, human reproduction and the health of the offspring. The causes of sDF are still unclear, even if apoptosis, oxidative assault and defects in chromatin maturation are hypothesized. Using multicolor flow cytometry and sperm sorting, we challenged the three hypothesized mechanisms by simultaneously evaluating sDF and signs of oxidative damage (8-hydroxy, 2′-deoxyguanosine [8-OHdG] and malondialdehyde [MDA]), apoptosis (caspase activity and cleaved poly[ADP-ribose] polymerase [cPARP]) and sperm immaturity (creatine phosphokinase [CK] and excess of residual histones). Active caspases and c-PARP were concomitant with sDF in a high percentage of spermatozoa (82.6% ± 9.1% and 53.5% ± 16.4%, respectively). Excess of residual histones was significantly higher in DNA-fragmented sperm versus sperm without DNA fragmentation (74.8% ± 17.5% and 37.3% ± 16.6%, respectively, p < 0.005), and largely concomitant with active caspases. Conversely, oxidative damage was scarcely concomitant with sDF in the total sperm population, at variance with live sperm, where 8-OHdG and MDA were clearly associated to sDF. In addition, most live cells with active caspase also showed 8-OHdG, suggesting activation of apoptotic pathways in oxidative-injured live cells. This is the first investigation on the origin of sDF directly evaluating the simultaneous presence of the signs of the hypothesized mechanisms with DNA breaks at the single cell level. The results indicate that the main pathway leading to sperm DNA breaks is a process of apoptosis, likely triggered by an impairment of chromatin maturation in the testis and by oxidative stress during the transit in the male genital tract. These findings are highly relevant for clinical studies on the effects of drugs on sDF and oxidative stress in infertile men and for the development of new therapeutic strategies. PMID:25786204

  5. Linking sperm length and velocity: the importance of intramale variation.

    PubMed

    Fitzpatrick, John L; Garcia-Gonzalez, Francisco; Evans, Jonathan P

    2010-12-23

    Selection imposed through sperm competition is commonly thought to promote the evolution of longer sperm, since sperm length is assumed to be positively associated with sperm swimming velocity. Yet, the basis for this assumption remains controversial, and there is surprisingly little intraspecific evidence demonstrating such a link between sperm form and function. Here, we show that sperm length and velocity are highly correlated in the sea urchin Heliocidaris erythrogramma, but importantly we report that failure to account for within-male variation in these sperm traits can obscure this relationship. These findings, in conjunction with the mounting evidence for extremely high levels of intra-specific variance in sperm traits, suggest that a functional link between sperm morphology and velocity may be more prevalent than what current evidence suggests. Our findings also suggest that selection for faster swimming sperm may promote the evolution of longer sperm, thereby supporting recent findings from macroevolutionary studies. PMID:20484233

  6. Hydrodynamics of Sperm Cells near Surfaces

    PubMed Central

    Elgeti, Jens; Kaupp, U. Benjamin; Gompper, Gerhard

    2010-01-01

    Sperm are propelled by an actively beating tail, and display a wide variety of swimming patterns. When confined between two parallel walls, sperm swim either in circles or on curvilinear trajectories close to the walls. We employ mesoscale hydrodynamics simulations in combination with a mechanical sperm model to study the swimming behavior near walls. The simulations show that sperm become captured at the wall due to the hydrodynamic flow fields which are generated by the flagellar beat. The circular trajectories are determined by the chiral asymmetry of the sperm shape. For strong (weak) chirality, sperm swim in tight (wide) circles, with the beating plane of the flagellum oriented perpendicular (parallel) to the wall. For comparison, we also perform simulations based on a local anisotropic friction of the flagellum. In this resistive force approximation, surface adhesion and circular swimming patterns are obtained as well. However, the adhesion mechanism is now due to steric repulsion, and the orientation of the beating plane is different. Our model provides a theoretical framework that explains several distinct swimming behaviors of sperm near and far from a wall. Moreover, the model suggests a mechanism by which sperm navigate in a chemical gradient via a change of their shape. PMID:20712984

  7. Predominance of sperm motion in corners.

    PubMed

    Nosrati, Reza; Graham, Percival J; Liu, Qiaozhi; Sinton, David

    2016-01-01

    Sperm migration through the female tract is crucial to fertilization, but the role of the complex and confined structure of the fallopian tube in sperm guidance remains unknown. Here, by confocal imaging microchannels head-on, we distinguish corner- vs. wall- vs. bulk-swimming bull sperm in confined geometries. Corner-swimming dominates with local areal concentrations as high as 200-fold that of the bulk. The relative degree of corner-swimming is strongest in small channels, decreases with increasing channel size, and plateaus for channels above 200 μm. Corner-swimming remains predominant across the physiologically-relevant range of viscosity and pH. Together, boundary-following sperm account for over 95% of the sperm distribution in small rectangular channels, which is similar to the percentage of wall swimmers in circular channels of similar size. We also demonstrate that wall-swimming sperm travel closer to walls in smaller channels (~100 μm), where the opposite wall is within the hydrodynamic interaction length-scale. The corner accumulation effect is more than the superposition of the influence of two walls, and over 5-fold stronger than that of a single wall. These findings suggest that folds and corners are dominant in sperm migration in the narrow (sub-mm) lumen of the fallopian tube and microchannel-based sperm selection devices. PMID:27211846

  8. Predominance of sperm motion in corners

    PubMed Central

    Nosrati, Reza; Graham, Percival J.; Liu, Qiaozhi; Sinton, David

    2016-01-01

    Sperm migration through the female tract is crucial to fertilization, but the role of the complex and confined structure of the fallopian tube in sperm guidance remains unknown. Here, by confocal imaging microchannels head-on, we distinguish corner- vs. wall- vs. bulk-swimming bull sperm in confined geometries. Corner-swimming dominates with local areal concentrations as high as 200-fold that of the bulk. The relative degree of corner-swimming is strongest in small channels, decreases with increasing channel size, and plateaus for channels above 200 μm. Corner-swimming remains predominant across the physiologically-relevant range of viscosity and pH. Together, boundary-following sperm account for over 95% of the sperm distribution in small rectangular channels, which is similar to the percentage of wall swimmers in circular channels of similar size. We also demonstrate that wall-swimming sperm travel closer to walls in smaller channels (~100 μm), where the opposite wall is within the hydrodynamic interaction length-scale. The corner accumulation effect is more than the superposition of the influence of two walls, and over 5-fold stronger than that of a single wall. These findings suggest that folds and corners are dominant in sperm migration in the narrow (sub-mm) lumen of the fallopian tube and microchannel-based sperm selection devices. PMID:27211846

  9. Advances in flow cytometry for sperm sexing.

    PubMed

    Sharpe, J C; Evans, K M

    2009-01-01

    This review presents the key technological developments that have been implemented in the 20 years since the first reports of successful measurement, sorting, insemination and live births using flow cytometry as a proven physical sperm separation technique. Since the first reports of sexed sperm, flow technology efforts have been largely focused on improving sample throughput by increasing the rate at which sperm are introduced to the sorter, and on improving measurement resolution, which has increased the proportion of cells that can be reliably measured and sorted. Today, routine high-purity sorting of X- or Y-chromosome-bearing sperm can be achieved at rates up to 8000 s(-1) for an input rate of 40,000 X- and Y-sperms(-1). With current protocols, straws of sex-sorted sperm intended for use in artificial insemination contain approximately 2 x 10(6)sperm. The sort rate of 8000 sperms(-1) mentioned above corresponds to a production capacity of approximately 14 straws of each sex per hour per instrument. PMID:18950849

  10. Predominance of sperm motion in corners

    NASA Astrophysics Data System (ADS)

    Nosrati, Reza; Graham, Percival J.; Liu, Qiaozhi; Sinton, David

    2016-05-01

    Sperm migration through the female tract is crucial to fertilization, but the role of the complex and confined structure of the fallopian tube in sperm guidance remains unknown. Here, by confocal imaging microchannels head-on, we distinguish corner- vs. wall- vs. bulk-swimming bull sperm in confined geometries. Corner-swimming dominates with local areal concentrations as high as 200-fold that of the bulk. The relative degree of corner-swimming is strongest in small channels, decreases with increasing channel size, and plateaus for channels above 200 μm. Corner-swimming remains predominant across the physiologically-relevant range of viscosity and pH. Together, boundary-following sperm account for over 95% of the sperm distribution in small rectangular channels, which is similar to the percentage of wall swimmers in circular channels of similar size. We also demonstrate that wall-swimming sperm travel closer to walls in smaller channels (~100 μm), where the opposite wall is within the hydrodynamic interaction length-scale. The corner accumulation effect is more than the superposition of the influence of two walls, and over 5-fold stronger than that of a single wall. These findings suggest that folds and corners are dominant in sperm migration in the narrow (sub-mm) lumen of the fallopian tube and microchannel-based sperm selection devices.

  11. Mass-Specific Metabolic Rate and Sperm Competition Determine Sperm Size in Marsupial Mammals

    PubMed Central

    Tourmente, Maximiliano; Gomendio, Montserrat; Roldan, Eduardo R. S.

    2011-01-01

    Two complementary hypotheses have been proposed to explain variation in sperm size. The first proposes that post-copulatory sexual selection favors an increase in sperm size because it enhances sperm swimming speed, which is an important determinant of fertilization success in competitive contexts. The second hypothesis proposes that mass-specific metabolic rate acts as a constraint, because large animals with low mass-specific metabolic rates will not be able to process resources at the rates needed to produce large sperm. This constraint is expected to be particularly pronounced among mammals, given that this group contains some of the largest species on Earth. We tested these hypotheses among marsupials, a group in which mass-specific metabolic rates are roughly 30% lower than those of eutherian mammals of similar size, leading to the expectation that metabolic rate should be a major constraint. Our findings support both hypotheses because levels of sperm competition are associated with increases in sperm size, but low mass-specific metabolic rate constrains sperm size among large species. We also found that the relationship between sperm size and mass-specific metabolic rate is steeper among marsupials and shallower among eutherian mammals. This finding has two implications: marsupials respond to changes in mass-specific metabolic rate by modifying sperm length to a greater extent, suggesting that they are more constrained by metabolic rate. In addition, for any given mass-specific metabolic rate, marsupials produce longer sperm. We suggest that this is the consequence of marsupials diverting resources away from sperm numbers and into sperm size, due to their efficient sperm transport along the female tract and the existence of mechanisms to protect sperm. PMID:21731682

  12. The sperm chromatin dispersion test: a simple method for the determination of sperm DNA fragmentation.

    PubMed

    Fernández, Jose Luis; Muriel, Lourdes; Rivero, Maria Teresa; Goyanes, Vicente; Vazquez, Rosana; Alvarez, Juan G

    2003-01-01

    Sperm DNA fragmentation is being increasingly recognized as an important cause of infertility. We herein describe the Sperm Chromatin Dispersion (SCD) test, a novel assay for sperm DNA fragmentation in semen. The SCD test is based on the principle that sperm with fragmented DNA fail to produce the characteristic halo of dispersed DNA loops that is observed in sperm with non-fragmented DNA, following acid denaturation and removal of nuclear proteins. This was confirmed by the analysis of DNA fragmentation using the specific DNA Breakage Detection-Fluorescence In Situ Hybridization (DBD-FISH) assay, which allows the detection of DNA breaks in lysed sperm nuclei. Sperm suspensions either prepared from semen or isolated from semen by gradient centrifugation were embedded in an agarose microgel on slides and treated with 0.08 N HCl and lysing solutions containing 0.8 M dithiothreitol (DTT), 1% sodium dodecyl sulfate (SDS), and 2 M NaCl. Then, the slides were sequentially stained with DAPI (4',6-diamidino-2-phenylindole) and/or the Diff-Quik reagent, and the percentages of sperm with nondispersed and dispersed chromatin loops were monitored by fluorescence and brightfield microscopy, respectively. The results indicate that all sperm with nondispersed chromatin displayed DNA fragmentation, as measured by DBD-FISH. Conversely, all sperm with dispersed chromatin had very low to undetectable DBD-FISH labeling. SCD test values were significantly higher in patients being screened for infertility than in normozoospermic sperm donors who had participated in a donor insemination program. The coefficient of variation obtained using 2 different observers, either by digital image analysis (DIA) or by brightfield microscopy scoring, was less than 3%. In conclusion, the SCD test is a simple, accurate, highly reproducible, and inexpensive method for the analysis of sperm DNA fragmentation in semen and processed sperm. Therefore, the SCD test could potentially be used as a routine test

  13. Sperm retrieval and fertilization in repeated percutaneous epididymal sperm aspiration.

    PubMed

    Rosenlund, B; Westlander, G; Wood, M; Lundin, K; Reismer, E; Hillensjö, T

    1998-10-01

    Percutaneous epididymal sperm aspiration (PESA) for retrieval of spermatozoa for intracytoplasmic sperm injection (ICSI) is a new simplified technique in the treatment of men with obstructive azoospermia. There has been a fear that the PESA procedure, being blind, could cause damage to the epididymal duct system and make it impossible to retrieve spermatozoa if a repeated procedure is required. We report here on repeated PESA procedures from the same unilateral epididymis. Twenty-seven men with obstructive azoospermia were investigated retrospectively regarding sufficiency of the number of motile spermatozoa for ICSI, fertilization rate (FR) and possibility of collecting spermatozoa for cryopreservation in repeated PESA procedures. Sufficient motile spermatozoa for ICSI were found in a similar proportion of men at the first two attempts: 91 and 89% respectively. Fertilization rate and the possibility of collecting spermatozoa for cryopreservation were also similar at the first two PESA procedures: 62 versus 67% and 33 versus 33% respectively. At the third procedure, motile spermatozoa for ICSI were retrieved in 86% (6/7), FR was 47% and spermatozoa were cryopreserved in one case. Two men underwent a fourth PESA. In both cases, a sufficient number of motile spermatozoa for ICSI was found and FR was 62%. This study shows that in men with obstructive azoospermia, PESA can be repeated on the same unilateral epididymis up to three times, with good opportunity of retrieving sufficient motile spermatozoa for ICSI.

  14. The Molecules of Sperm Exocytosis.

    PubMed

    Belmonte, Silvia A; Mayorga, Luis S; Tomes, Claudia N

    2016-01-01

    Exocytosis is a fundamental process used by eukaryotic cells to release biological compounds and to insert lipids and proteins in the plasma membrane. Specialized secretory cells undergo regulated exocytosis in response to physiological signals. Sperm exocytosis or acrosome reaction (AR) is essentially a regulated secretion with special characteristics. We will focus here on some of these unique features, covering the topology, kinetics, and molecular mechanisms that prepare, drive, and regulate membrane fusion during the AR. Last, we will compare acrosomal release with exocytosis in other model systems.

  15. Mammalian sperm interactions with the female reproductive tract.

    PubMed

    Suarez, Susan S

    2016-01-01

    The mammalian female reproductive tract interacts with sperm in various ways in order to facilitate sperm migration to the egg while impeding migrations of pathogens into the tract, to keep sperm alive during the time between mating and ovulation, and to select the fittest sperm for fertilization. The two main types of interactions are physical and molecular. Physical interactions include the swimming responses of sperm to the microarchitecture of walls, to fluid flows, and to fluid viscoelasticity. When sperm encounter walls, they have a strong tendency to remain swimming along them. Sperm will also orient their swimming into gentle fluid flows. The female tract seems to use these tendencies of sperm to guide them to the site of fertilization. When sperm hyperactivate, they are better able to penetrate highly viscoelastic media, such as the cumulus matrix surrounding eggs. Molecular interactions include communications of sperm surface molecules with receptors on the epithelial lining of the tract. There is evidence that specific sperm surface molecules are required to enable sperm to pass through the uterotubal junction into the oviduct. When sperm reach the oviduct, most bind to the oviductal epithelium. This interaction holds sperm in a storage reservoir until ovulation and serves to maintain the fertilization competence of stored sperm. When sperm are released from the reservoir, they detach from and re-attach to the epithelium repeatedly while ascending to the site of fertilization. We are only beginning to understand the communications that may pass between sperm and epithelium during these interactions.

  16. New era in sperm selection for ICSI.

    PubMed

    Nasr-Esfahani, M H; Deemeh, M R; Tavalaee, M

    2012-08-01

    Spermatozoa contribute to approximately half of the genome of future progeny, and therefore, have a profound impact on embryo development post-fertilization. Sperm selection based on viability and normal morphology does not eliminate the chance for DNA damaged spermatozoa to be inseminated and may account for a considerable percentage of failed embryo development post-ICSI (Intra cytoplasmic sperm injection). Therefore, sperm selection based on functional sperm characteristics to preclude insemination of DNA damaged spermatozoa have paved the way for successful ICSI outcomes. In regard to this, different laboratories have introduced novel procedures to replace traditional or orthodox sperm selection methods. This review attempts to provide information on the scientific bases of each procedure, and pinpoint their advantages and disadvantages. In addition to data from our research, a systematic search on the literature, publications and presentations was carried out using such databases as PubMed and ISI-Web.

  17. Semen characteristics and sperm morphology in the Arabian leopard (Panthera pardus nimr) and how these vary with age and season.

    PubMed

    de Haas van Dorsser, Florine J; Strick, Jacqueline A

    2005-01-01

    The Arabian leopard is a critically endangered species. Since there are only an estimated 200 animals remaining in the wild, careful management of the captive population is necessary to minimise inbreeding. The objective of this study was to characterise sperm morphology and ejaculate quality in captive males. Semen was collected by electroejaculation from 8 adult captive male leopards (aged 2-16 years) during the summer and winter months, and semen parameters, including sperm morphology, were assessed. Two-year-old leopards showed lower total sperm counts per ejaculate than older animals and these counts declined at > 8 years. Ejaculates collected during the hot summer showed significantly lower sperm concentrations, total sperm counts, sperm motility and viability and percentage of spermatozoa showing normal morphology than ejaculates collected in the cooler winter. The results showed that the male leopard attains sexual maturity between 2 and 3 years of age and exhibits good semen quality until 8 years. Collection of semen for artificial breeding or banking would best be carried out in the cooler winter months.

  18. Assessment of chromatin status (SCSA) in epididymal and ejaculated sperm in Iberian red deer, ram and domestic dog.

    PubMed

    Garcia-Macias, Vanesa; Martinez-Pastor, Felipe; Alvarez, Mercedes; Garde, Jose Julian; Anel, Enrique; Anel, Luis; de Paz, Paulino

    2006-11-01

    Abnormal chromatin condensation is not detected using classical techniques for sperm analysis. SCSA has demonstrated its usefulness in sperm chromatin analysis in several species (human, bull, stallion and boar). In this work, we studied sperm samples from red deer, ram and dog to analyze the differentiation of chromatin structure applying SCSA in epididymal and ejaculated spermatozoa. Epididymal samples were obtained from the caput, corpus and cauda by means of cuts, and ejaculated ones were obtained by electroejaculation (deer), artificial vagina (ram) and digital manipulation (dog). SCSA results suggested different critical points in sperm maturation (spermatozoa with loose chromatin to more condensed chromatin) among species: from corpus to cauda in ram and from caput to corpus in deer and dog. Moreover, we also detected differences in ruminants and dog, reflected in the appearance of SCSA plots. Indeed, ram and deer samples rendered two peaks within the sperm main population (sperm with condensed chromatin), whereas only one was detected in dog. Although some differences were observed between cauda and ejaculated samples, SCSA parameters indicated good chromatin condensation, making these samples suitable for germplasm banking. Some species-dependent modifications in the analysis of the results may be necessary to take full advantage of its analytical power.

  19. Pronuclear synchronization and nuclear morphology of mature and in vitro matured oocytes in the rat: an ultrastructural study.

    PubMed

    Cincik, M; Baykal, B; Zeteroglu, S; Onalan, G; Ceyhan, S T; Ergur, R

    2005-01-01

    The objective of this study was to evaluate synchronous and asynchronous pronucleus (PN) formation and the related patterns of juxtapositional nucleolus (n) formation in immature (prophase I [PI] and metaphase I [MI]) and mature (metaphase II [MII]) oocytes after fertilization, both ultrastructurally and at the level of light microscope. A single dose of 15 IU gonadotrophin was injected subcutaneously to twenty four 26-wk-old, female Wistar rats to induce ovulation. Human chorionic gonadotrophin (4 IU) was administered 40 h later, and after 4-6 h the ovaries were dissected, and the oocytes were aspirated. A total of 214 rat oocytes were classified according to a maturation index as follows: group I, 80 PI oocytes; group II, 50 MI oocytes; and group III, 84 MII oocytes. Immature oocytes were in vitro matured for 18-36 h. Spermatozoa were acquired by microepididymal sperm aspiration and processed using swim-up technique. Intracytoplasmic sperm injection was performed on mature oocytes after 2 h of incubation and on in vitro matured (IVM) oocytes 4 h after maturation. Pronuclear synchronization [both pronucleases (PNs) centrally located, equal sized, with equal numbers and sizes of juxtapositional nucleoli (Nn)] was observed in fertilized oocytes. Asynchronous PN formation (diversity between male and female PNs, related to dimensions, localization, and the number of Nn) in groups I, II, and III was found in 75, 86, and 47% of preembryos, respectively. There was a significant difference of synchronous pronuclear formation between mature and IVM oocytes (P < 0.05). In IVM oocytes, asynchronous PN formation is high, and juxtapositional pronucleolar patterns are observed to be low by transmission electron microscope (TEM).

  20. The effects of cooling rates and type of freezing extenders on cryosurvival of rat sperm

    PubMed Central

    Varisli, Omer; Scott, Hollie; Agca, Cansu; Agca, Yuksel

    2013-01-01

    Cryopreservation of rat sperm is very challenging due to its sensitivity to various stress factors. The objective of this study was to determine the optimal cooling rate and extender for epididymal sperm of outbred Sprague Dawley (SD) and inbred Fischer 344 (F344) rat strains. The epididymal sperm from 10–12 weeks old sexually mature SD and F344 strains were suspended in five different freezing extenders, namely HEPES buffered Tyrode’s lactate (TL-HEPES), modified Kreb’s Ringer bicarbonate (mKRB), 3% dehydrated skim milk (SM), Salamon’s Tris-citrate (TRIS), and tes/tris (TES). All extenders contained 20% egg yolk, 0.75% Equex Paste and 0.1 M raffinose or 0.1 M sucrose. The sperm samples in each extender were cooled to 4°C and held for 45 min for equilibration before freezing. The equilibrated sperm samples in each extender were placed onto a shallow quartz dish inserted into Linkam Cryostage (BCS 196). The samples were then cooled to a final temperature of −150 °C by using various cooling rates (10, 40, 70, and 100 °C/min). For thawing, the quartz dish containing the sperm samples were rapidly removed from the Linkam cryo-stage and placed on a 37 °C slide warmer and held for 1 min before motility analysis. Sperm membrane and acrosomal integrity and mitochondrial membrane potential (MMP) were assessed by SYBR-14/Propidium iodide, Alexa Fluor-488-PNA conjugate and JC-1, respectively. The total motility, acrosomal integrity, membrane integrity and MMP values were compared among cooling rates and extenders. Both cooling rate and type of extender had significant effect on cryosurvival (P<0.05). Sperm motility increased as cooling rate was increased for both strains (P<0.05). Highest cryosurvival was achieved when 100 °C/min cooling rate was used in combination with TES extender containing 20% egg yolk, 0.75% Equex paste and either 0.1 M sucrose or raffinose (P < 0.05). This study showed that TES extender containing 0.1 M raffinose or sucrose with 70

  1. Sperm Chromatin Immaturity Observed in Short Abstinence Ejaculates Affects DNA Integrity and Longevity In Vitro

    PubMed Central

    Salian, Sujith Raj; Kumar, Dayanidhi; Singh, Vikram Jeet; D’Souza, Fiona; Kalthur, Guruprasad; Kamath, Asha; Adiga, Satish Kumar

    2016-01-01

    Background The influence of ejaculatory abstinence (EA) on semen parameters and subsequent reproductive outcome is still debatable; hence understanding the impact of EA on sperm structural and functional integrity may provide a valuable information on predicting successful clinical outcome. Objective To understand the influence of EA on sperm chromatin maturity, integrity, longevity and global methylation status. Methods This experimental prospective study included 76 ejaculates from 19 healthy volunteers who provided ejaculates after observing 1, 3, 5 and 7 days of abstinence. Sperm chromatin maturity, DNA integrity and global methylation status were assessed in the neat ejaculate. Sperm motility, DNA integrity and longevity were assessed in the processed fraction of the fresh and frozen-thawed ejaculates to determine their association with the length of EA. Results Spermatozoa from 1 day ejaculatory abstinence (EA-1) displayed significantly higher level of sperm chromatin immaturity in comparison to EA-3 (P < 0.05) and EA-5 (P < 0.01) whereas; the number of 5-methyl cytosine immunostained spermatozoa did not vary significantly across groups. On the other hand, in vitro incubation of processed ejaculate from EA-1 resulted in approximately 20 and 40 fold increase in the DNA fragmented spermatozoa at the end of 6 and 24h respectively (P < 0.01–0.001). Conclusion Use of short-term EA for therapeutic fertilization would be a clinically valuable strategy to improve the DNA quality. However, use of such spermatozoa after prolonged incubation in vitro should be avoided as it can carry a substantial risk of transmitting DNA fragmentation to the oocytes. PMID:27043437

  2. Effects of cytoplasmic genes on sperm viability and sperm morphology in a seed beetle: implications for sperm competition theory?

    PubMed

    Dowling, D K; Nowostawski, A Larkeson; Arnqvist, G

    2007-01-01

    Sperm competition theory predicts that sperm traits influencing male fertilizing ability will evolve adaptively. However, it has been suggested that some sperm traits may be at least partly encoded by mitochondrial genes. If true, this may constrain the adaptive evolution of such traits because mitochondrial DNA (mtDNA) is maternally inherited and there is thus no selection on mtDNA in males. Phenotypic variation in such traits may nevertheless be high because mutations in mtDNA that have deleterious effects on male traits, but neutral or beneficial effects in females, may be maintained by random processes or selection in females. We used backcrossing to create introgression lines of seed beetles (Callosobruchus maculatus), carrying orthogonal combinations of distinct lineages of cytoplasmic and nuclear genes, and then assayed sperm viability and sperm length in all lines. We found sizeable cytoplasmic effects on both sperm traits and our analyses also suggested that the cytoplasmic effects varied across nuclear genetic backgrounds. We discuss some potential implications of these findings for sperm competition theory.

  3. Protein and carbohydrate intake influence sperm number and fertility in male cockroaches, but not sperm viability

    PubMed Central

    Bunning, Harriet; Rapkin, James; Belcher, Laurence; Archer, C. Ruth; Jensen, Kim; Hunt, John

    2015-01-01

    It is commonly assumed that because males produce many, tiny sperm, they are cheap to produce. Recent work, however, suggests that sperm production is not cost-free. If sperm are costly to produce, sperm number and/or viability should be influenced by diet, and this has been documented in numerous species. Yet few studies have examined the exact nutrients responsible for mediating these effects. Here, we quantify the effects of protein (P) and carbohydrate (C) intake on sperm number and viability in the cockroach Nauphoeta cinerea, as well as the consequences for male fertility. We found the intake of P and C influenced sperm number, being maximized at a high intake of diets with a P : C ratio of 1 : 2, but not sperm viability. The nutritional landscapes for male fertility and sperm number were closely aligned, suggesting that sperm number is the major determinant of male fertility in N. cinerea. Under dietary choice, males regulate nutrient intake at a P : C ratio of 1 : 4.95, which is midway between the ratios needed to maximize sperm production and pre-copulatory attractiveness in this species. This raises the possibility that males regulate nutrient intake to balance the trade-off between pre- and post-copulatory traits in this species. PMID:25608881

  4. Protein and carbohydrate intake influence sperm number and fertility in male cockroaches, but not sperm viability.

    PubMed

    Bunning, Harriet; Rapkin, James; Belcher, Laurence; Archer, C Ruth; Jensen, Kim; Hunt, John

    2015-03-01

    It is commonly assumed that because males produce many, tiny sperm, they are cheap to produce. Recent work, however, suggests that sperm production is not cost-free. If sperm are costly to produce, sperm number and/or viability should be influenced by diet, and this has been documented in numerous species. Yet few studies have examined the exact nutrients responsible for mediating these effects. Here, we quantify the effects of protein (P) and carbohydrate (C) intake on sperm number and viability in the cockroach Nauphoeta cinerea, as well as the consequences for male fertility. We found the intake of P and C influenced sperm number, being maximized at a high intake of diets with a P : C ratio of 1 : 2, but not sperm viability. The nutritional landscapes for male fertility and sperm number were closely aligned, suggesting that sperm number is the major determinant of male fertility in N. cinerea. Under dietary choice, males regulate nutrient intake at a P : C ratio of 1 : 4.95, which is midway between the ratios needed to maximize sperm production and pre-copulatory attractiveness in this species. This raises the possibility that males regulate nutrient intake to balance the trade-off between pre- and post-copulatory traits in this species.

  5. Sperm characterization and identification of sperm sub-populations in ejaculates from pampas deer (Ozotoceros bezoarticus).

    PubMed

    Beracochea, F; Gil, J; Sestelo, A; Garde, J J; Santiago-Moreno, J; Fumagalli, F; Ungerfeld, R

    2014-10-01

    Pampas deer (Ozotoceros bezoarticus) is a native endangered species. Knowledge of the basic spermiogram characteristics and the morphometric descriptors is necessary to effectively develop sperm cryopreservation. In other species, sperm sub-population is related to sperm cryo-resistance. The objective was to provide a general description of the sperm, including sperm head morphometric descriptors, its repeatability, and the existence of sperm sub-populations. Sperm were obtained from adult males by electroejaculation during the breeding season. The motility score was 3.4 ± 0.2 (mean ± SEM) and progressive motility was 59.4 ± 3.7%. Ejaculated volume was 413.9 ± 51.0 μl, the total number of sperm ejaculated was 321.2 ± 55.4 × 10(6). Also, 63.3 ± 3.1% of the sperm were morphologically abnormal and 23.7 ± 2.3% had acrosome damage. The sperm head length was 7.6 ± 0.01 μm, width 4.4 ± 0.01 μm, area 28.1 ± 0.07 μm(2) and the perimeter was 21.9 ± 0.04 μm. There was a positive relationship among morphometric descriptors and the motility score, overall motility and progressive motility. Also length (P=0.011), width (P=0.003), area (P=0.006) and perimeter (P=0.009) of sperm head obtained in two different collections were positively related. Overall, the low concentration, volume, overall quality and abnormal morphology, and wide variation of these variables may be a limitation for the development of sperm cryopreserved banks. There were three sperm sub-populations with different morphometric characteristics. The morphometric descriptors are maintained similarly among different collections. PMID:25104472

  6. Echinococcus multilocularis Leuckart, 1863 (Taeniidae): new data on sperm ultrastructure.

    PubMed

    Miquel, Jordi; Świderski, Zdzisław; Azzouz-Maache, Samira; Pétavy, Anne-Françoise

    2016-06-01

    The present study establishes the ultrastructural organisation of the mature spermatozoon of Echinococcus multilocularis, which is essential for future research on the location of specific proteins involved in the sperm development in this species and also in Echinococcus granulosus. Thus, the ultrastructural characteristics of the sperm cell are described by means of transmission electron microscopy. The spermatozoon of E. multilocularis is a filiform cell, which is tapered at both extremities and lacks mitochondria. It exhibits all the characteristics of type VII spermatozoon of tapeworms, namely a single axoneme, crested bodies, spiralled cortical microtubules and nucleus, a periaxonemal sheath and intracytoplasmic walls. Other characteristics observed in the male gamete are the presence of a >900-nm long apical cone in its anterior extremity and only the axoneme in its posterior extremity. The ultrastructural characters of the spermatozoon of E. multilocularis are compared with those of other cestodes studied to date, with particular emphasis on representatives of the genus Taenia. The most interesting finding concerns the presence of two helical crested bodies in E. multilocularis while in the studied species of Taenia, there is only one crested body. Future ultrastructural studies of other species of the genus Echinococcus would be of particular interest in order to confirm whether or not the presence of two crested bodies is a characteristic of this genus. PMID:26960958

  7. Selenoprotein P in seminal fluid is a novel biomarker of sperm quality.

    PubMed

    Michaelis, Marten; Gralla, Oliver; Behrends, Thomas; Scharpf, Marcus; Endermann, Tobias; Rijntjes, Eddy; Pietschmann, Nicole; Hollenbach, Birgit; Schomburg, Lutz

    2014-01-17

    Hepatically-derived selenoprotein P (SePP) transports selenium (Se) via blood to other tissues including the testes. Male Sepp-knockout mice are infertile. SePP-mediated Se transport to Sertoli cells is needed for supporting biosynthesis of the selenoenzyme glutathione peroxidase-4 (GPX4) in spermatozoa. GPX4 becomes a structural component of sperm midpiece during sperm maturation, and its expression correlates to semen quality. We tested whether SePP is also present in seminal plasma, potentially correlating to fertility parameters. Semen quality was assessed by sperm density, morphology and motility. SePP was measured by an immunoluminometric assay, and trace elements were determined by X-ray fluorescence spectroscopy. SePP levels were considerably lower in seminal plasma as compared to serum (0.4±0.1 mg/l vs. 3.5±1.0 mg/l); Se concentrations showed a similar but less pronounced difference (48.9±20.7 μg/l vs. 106.7±17.3 μg/l). Se and Zn correlated positively in seminal fluid but not in serum. Seminal plasma SePP concentrations were independent of serum SePP concentrations, but correlated positively to sperm density and fraction of vital sperm. SePP concentrations in seminal plasma of vasectomized men were similar to controls indicating that accessory sex glands are a testes-independent source of SePP. This notion was corroborated by histochemical analyses localizing SePP in epithelial cells of seminal vesicles. We conclude that SePP is not only involved in Se transport to testes supporting GPX4 biosynthesis but it also becomes secreted into seminal plasma, likely important to protect sperm during storage, genital tract passage and final journey.

  8. Syntaxin and VAMP association with lipid rafts depends on cholesterol depletion in capacitating sperm cells.

    PubMed

    Tsai, Pei-Shiue; De Vries, Klaas J; De Boer-Brouwer, Mieke; Garcia-Gil, Nuria; Van Gestel, Renske A; Colenbrander, Ben; Gadella, Bart M; Van Haeften, Theo

    2007-01-01

    Sperm cells represent a special exocytotic system since mature sperm cells contain only one large secretory vesicle, the acrosome, which fuses with the overlying plasma membrane during the fertilization process. Acrosomal exocytosis is believed to be regulated by activation of SNARE proteins. In this paper, we identified specific members of the SNARE protein family, i.e., the t-SNAREs syntaxin1 and 2, and the v-SNARE VAMP, present in boar sperm cells. Both syntaxins were predominantly found in the plasma membrane whereas v-SNAREs are mainly located in the outer acrosomal membrane of these cells. Under non-capacitating conditions both syntaxins and VAMP are scattered in well-defined punctate structures over the entire sperm head. Bicarbonate-induced in vitro activation in the presence of BSA causes a relocalization of these SNAREs to a more homogeneous distribution restricted to the apical ridge area of the sperm head, exactly matching the site of sperm zona binding and subsequent induced acrosomal exocytosis. This redistribution of syntaxin and VAMP depends on cholesterol depletion and closely resembles the previously reported redistribution of lipid raft marker proteins. Detergent-resistant membrane isolation and subsequent analysis shows that a significant proportion of syntaxin emerges in the detergent-resistant membrane (raft) fraction under such conditions, which is not the case under those conditions where cholesterol depletion is blocked. The v-SNARE VAMP displays a similar cholesterol depletion-dependent lateral and raft redistribution. Taken together, our results indicate that redistribution of syntaxin and VAMP during capacitation depends on association of these SNAREs with lipid rafts and that such a SNARE-raft association may be essential for spatial control of exocytosis and/or regulation of SNARE functioning.

  9. Human sperm aster formation and pronuclear decondensation in bovine eggs following intracytoplasmic sperm injection using a Piezo-driven pipette: a novel assay for human sperm centrosomal function.

    PubMed

    Nakamura, S; Terada, Y; Horiuchi, T; Emuta, C; Murakami, T; Yaegashi, N; Okamura, K

    2001-11-01

    In human fertilization, the sperm introduces the centrosome; the microtubule-organizing center and microtubules are organized within the inseminated egg from the sperm centrosome. These microtubules form a radial array, called the sperm aster, the functioning of which is essential to pronuclear movement for union of male and female genome. The sperm centrosomal function is considered to be necessary for the normal human fertilization process. Therefore, the dysfunction of sperm centrosome is a possible cause of human fertilization failure. However, little information is available regarding human sperm centrosomal function during fertilization in clinically assisted reproductive technology. To assess the human sperm centrosomal function, we examined sperm aster formation and pronuclear decondensation following intracytoplasmic sperm injection (ICSI) with human sperm into the bovine egg using a Piezo-driven pipette and ethanol activation of eggs. After human sperm incorporation into bovine egg, we observed that the sperm aster was organized from sperm centrosome, and that the sperm aster was enlarged as the sperm nuclei underwent pronuclear formation. The sperm aster formation rate at 6 h post-ICSI and the male pronuclear formation rate at 8-12 h post-ICSI were 60.0% and 83.3%, respectively. No difference of the sperm aster formation rate and the male pronuclear formation rate was observed between eggs activated with ethanol and eggs without artificial activation. We concluded that this heterologous Piezo-ICSI system into bovine egg can be a novel assay for human sperm centrosomal function, and it is possible to explicate a course of fertilization failure that was unknown until now.

  10. Suspended sediments limit coral sperm availability.

    PubMed

    Ricardo, Gerard F; Jones, Ross J; Clode, Peta L; Humanes, Adriana; Negri, Andrew P

    2015-01-01

    Suspended sediment from dredging activities and natural resuspension events represent a risk to the reproductive processes of coral, and therefore the ongoing maintenance of reefal populations. To investigate the underlying mechanisms that could reduce the fertilisation success in turbid water, we conducted several experiments exposing gametes of the corals Acropora tenuis and A. millepora to two sediment types. Sperm limitation was identified in the presence of siliciclastic sediment (230 and ~700 mg L(-1)), with 2-37 fold more sperm required to achieve maximum fertilisation rates, when compared with sediment-free treatments. This effect was more pronounced at sub-optimum sperm concentrations. Considerable (>45%) decreases in sperm concentration at the water's surface was recorded in the presence of siliciclastic sediment and a >20% decrease for carbonate sediment. Electron microscopy then confirmed sediment entangled sperm and we propose entrapment and sinking is the primary mechanism reducing sperm available to the egg. Longer exposure to suspended sediments and gamete aging further decreased fertilisation success when compared with a shorter exposure. Collectively, these findings demonstrate that high concentrations of suspended sediments effectively remove sperm from the water's surface during coral spawning events, reducing the window for fertilisation with potential subsequent flow-on effects for recruitment. PMID:26659008

  11. Clinical implications of sperm DNA damage.

    PubMed

    Lewis, Sheena E M; Simon, Luke

    2010-12-01

    Traditionally, the diagnosis of male infertility has relied upon microscopic assessment and biochemical assays to determine human semen quality. These tests are essential to provide the fundamental information on which clinicians base their initial diagnosis. However, none of these parameters addresses sperm function and their clinical value in predicting fertility is questionable. The advent of intracytoplasmic sperm injection (ICSI) has further reduced the significance and perceived need for sperm quality tests since ICSI requires only one sperm for the procedure to be successful. Even the conventional measures of sperm quality in terms of normal morphology or motility are not necessary for successful ICSI. Funding of andrological research has been neglected and improvement in assisted reproductive technology (ART) success has suffered as a consequence. Testing of sperm DNA damage shows much promise both as a diagnostic test for male infertility and a prognostic test for ART outcomes. It has been shown to be closely associated with numerous fertility outcomes including negative relationships with fertilization, embryo quality, implantation and positive relationships with miscarriage and childhood diseases. Here we report the relationships between in vitro fertilisation, ICSI pregnancy rates and sperm DNA damage, using the Comet assay to measure DNA fragmentation and also a novel test to measure modified bases, as a indication of oxidative DNA injury.

  12. [Can specialized sperm analysis predict fertilization ability?].

    PubMed

    Hakima, N; Sermondade, N; Sifer, C

    2012-09-01

    Conventional in vitro fertilization (cIVF) is an assisted reproductive technologies (ART) procedure, which requires both a sufficient number of motile sperm to be inseminated around the oocyte but also an optimal fertilizing ability of the inseminated sperm. Thus, the frequency of the risk that this method leads to a failure of fertilization varies depending on the cIVF indication and is enhanced if no factor of infertility was found in the first-line examination, suggesting a "qualitative" incapacity of the sperm to fertilize. Thus, many secondary sperm tests have been studied to know whether they could predict such fertilization failure The aim of this review is then to analyze the literature interested on these secondary specialized explorations sperm and their ability to predict the fertilization rate following cIVF, especially when an idiopathic (normal conventional sperm examination, including normal pelvic laparoscopy) or a pseudo-idiopathic infertility (normal conventional sperm examination, but non-done pelvic laparoscopy) are suspected.

  13. Suspended sediments limit coral sperm availability

    PubMed Central

    Ricardo, Gerard F.; Jones, Ross J.; Clode, Peta L.; Humanes, Adriana; Negri, Andrew P.

    2015-01-01

    Suspended sediment from dredging activities and natural resuspension events represent a risk to the reproductive processes of coral, and therefore the ongoing maintenance of reefal populations. To investigate the underlying mechanisms that could reduce the fertilisation success in turbid water, we conducted several experiments exposing gametes of the corals Acropora tenuis and A. millepora to two sediment types. Sperm limitation was identified in the presence of siliciclastic sediment (230 and ~700 mg L−1), with 2–37 fold more sperm required to achieve maximum fertilisation rates, when compared with sediment-free treatments. This effect was more pronounced at sub-optimum sperm concentrations. Considerable (>45%) decreases in sperm concentration at the water’s surface was recorded in the presence of siliciclastic sediment and a >20% decrease for carbonate sediment. Electron microscopy then confirmed sediment entangled sperm and we propose entrapment and sinking is the primary mechanism reducing sperm available to the egg. Longer exposure to suspended sediments and gamete aging further decreased fertilisation success when compared with a shorter exposure. Collectively, these findings demonstrate that high concentrations of suspended sediments effectively remove sperm from the water’s surface during coral spawning events, reducing the window for fertilisation with potential subsequent flow-on effects for recruitment. PMID:26659008

  14. Redox regulation of mammalian sperm capacitation

    PubMed Central

    O’Flaherty, Cristian

    2015-01-01

    Capacitation is a series of morphological and metabolic changes necessary for the spermatozoon to achieve fertilizing ability. One of the earlier happenings during mammalian sperm capacitation is the production of reactive oxygen species (ROS) that will trigger and regulate a series of events including protein phosphorylation, in a time-dependent fashion. The identity of the sperm oxidase responsible for the production of ROS involved in capacitation is still elusive, and several candidates are discussed in this review. Interestingly, ROS-induced ROS formation has been described during human sperm capacitation. Redox signaling during capacitation is associated with changes in thiol groups of proteins located on the plasma membrane and subcellular compartments of the spermatozoon. Both, oxidation of thiols forming disulfide bridges and the increase on thiol content are necessary to regulate different sperm proteins associated with capacitation. Reducing equivalents such as NADH and NADPH are necessary to support capacitation in many species including humans. Lactate dehydrogenase, glucose-6-phospohate dehydrogenase, and isocitrate dehydrogenase are responsible in supplying NAD (P) H for sperm capacitation. Peroxiredoxins (PRDXs) are newly described enzymes with antioxidant properties that can protect mammalian spermatozoa; however, they are also candidates for assuring the regulation of redox signaling required for sperm capacitation. The dysregulation of PRDXs and of enzymes needed for their reactivation such as thioredoxin/thioredoxin reductase system and glutathione-S-transferases impairs sperm motility, capacitation, and promotes DNA damage in spermatozoa leading to male infertility. PMID:25926608

  15. Females become infertile as the stored sperm's oxygen radicals increase

    PubMed Central

    Reinhardt, Klaus; Ribou, Anne-Cecile

    2013-01-01

    Predicting infertility is central to reproductive biology, medicine and evolutionary biology. In-vitro studies suggest that oxidative sperm damage causes infertility. Oxidative sperm damage can be reduced via two fundamental pathways: the removal of oxygen radicals by antioxidants, or the interference with cell metabolism to reduce the formation of oxygen radicals. Oxidative damage protection of spermatozoa should evolve frequently, especially during female sperm storage. However, in-vivo evidence linking oxidative protection and fertility is rare. We show that the intra-sperm production rate of oxygen radicals and the sperm metabolic rate were reduced in female bedbugs, Cimex lectularius, compared to males, and females laid fertile eggs. Females became infertile when sperm oxygen radicals and sperm metabolic rate increased to male levels. Our results link female fitness to sublethal sperm damage, imply adaptive benefits of interfering with sperm metabolism and offer the hypothesis that polyandry may serve to replace low-quality sperm.

  16. [Sperm selection in assisted reproductive technology: an update].

    PubMed

    Song, Yue-Qiang; Sha, Yan-Wei; Li, Ping

    2012-08-01

    Sperm selection plays an important role in assisted reproductive technology. In recent years, sperm evaluation is not limited to the assessment of sperm motility and morphology, but involves more other sperm characteristics such as sperm ultrastructure, DNA integrity, apoptosis and membrane. Assessment based on these characteristics is becoming the aim of sperm selection. This article gives an overview on several newly developed techniques for sperm selection according to different technical principles, such as electrophoretic separation, zeta potential, HA binding, Annexin V binding, intracytoplasmic morphologically selected sperm injection (IMSI) and microfluidic sperm sorter, which have all been applied to IVF or ICSI with the exception of microfluidic sperm sorter. It also introduces the advantages, disadvantages and application effects of these techniques.

  17. In vitro maturation and in vitro fertilization of mouse oocytes and preimplantation embryo culture.

    PubMed

    Kidder, Benjamin L

    2014-01-01

    Epigenetic regulation of gene expression in the germline is important for reproductive success of mammals. Misregulation of genes whose expression is correlated with reproductive success may result in subfertility or infertility. To study epigenetic events that occur during oocyte maturation and preimplantation embryo development, it is important to generate large numbers of ovarian follicles and embryos. Oocyte maturation can be modeled using in vitro maturation (IVM), which is a system of maturing ovarian follicles in a culture dish. In addition, fertilization and early embryogenesis can be modeled using in vitro fertilization (IVF), which involves the fertilization of mature oocytes with capacitated sperm in a culture dish. Here, we describe protocols for in vitro maturation (IVM) and in vitro fertilization (IVF) of mouse oocytes and preimplantation embryo culture. These protocols are suitable for the study of oocyte and embryo biology and the production of embryonic mice. PMID:24743999

  18. Patterns of sperm damage in Chernobyl passerine birds suggest a trade-off between sperm length and integrity.

    PubMed

    Hermosell, Ignacio G; Laskemoen, Terje; Rowe, Melissah; Møller, Anders P; Mousseau, Timothy A; Albrecht, Tomás; Lifjeld, Jan T

    2013-10-23

    Interspecific variation in sperm size is enigmatic, but generally assumed to reflect species-specific trade-offs in selection pressures. Among passerine birds, sperm length varies sevenfold, and sperm competition risk seems to drive the evolution of longer sperm. However, little is known about factors favouring short sperm or constraining the evolution of longer sperm. Here, we report a comparative analysis of sperm head abnormalities among 11 species of passerine bird in Chernobyl, presumably resulting from chronic irradiation following the 1986 accident. Frequencies of sperm abnormalities varied between 15.7 and 77.3% among species, more than fourfold higher than in uncontaminated areas. Nonetheless, species ranked similarly in sperm abnormalities in unpolluted areas as in Chernobyl, pointing to intrinsic factors underlying variation in sperm damage among species. Scanning electron microscopy of abnormal spermatozoa revealed patterns of acrosome damage consistent with premature acrosome reaction. Sperm length, but not sperm competition risk explained variation in sperm damage among species. This suggests that longer spermatozoa are more susceptible to premature acrosome reaction. Therefore, we hypothesize a trade-off between sperm length and sperm integrity affecting sperm evolution in passerine birds.

  19. Patterns of sperm damage in Chernobyl passerine birds suggest a trade-off between sperm length and integrity

    PubMed Central

    Hermosell, Ignacio G.; Laskemoen, Terje; Rowe, Melissah; Møller, Anders P.; Mousseau, Timothy A.; Albrecht, Tomáš; Lifjeld, Jan T.

    2013-01-01

    Interspecific variation in sperm size is enigmatic, but generally assumed to reflect species-specific trade-offs in selection pressures. Among passerine birds, sperm length varies sevenfold, and sperm competition risk seems to drive the evolution of longer sperm. However, little is known about factors favouring short sperm or constraining the evolution of longer sperm. Here, we report a comparative analysis of sperm head abnormalities among 11 species of passerine bird in Chernobyl, presumably resulting from chronic irradiation following the 1986 accident. Frequencies of sperm abnormalities varied between 15.7 and 77.3% among species, more than fourfold higher than in uncontaminated areas. Nonetheless, species ranked similarly in sperm abnormalities in unpolluted areas as in Chernobyl, pointing to intrinsic factors underlying variation in sperm damage among species. Scanning electron microscopy of abnormal spermatozoa revealed patterns of acrosome damage consistent with premature acrosome reaction. Sperm length, but not sperm competition risk explained variation in sperm damage among species. This suggests that longer spermatozoa are more susceptible to premature acrosome reaction. Therefore, we hypothesize a trade-off between sperm length and sperm integrity affecting sperm evolution in passerine birds. PMID:24088561

  20. Concurrent use of flow cytometry and fluorescence in-situ hybridization techniques for detecting faulty meiosis in a human sperm sample.

    PubMed

    Weissenberg, R; Aviram, A; Golan, R; Lewin, L M; Levron, J; Madgar, I; Dor, J; Barkai, G; Goldman, B

    1998-01-01

    Routine semen analysis in an infertile patient revealed severe teratospermia associated with malformation of head and tail in 100% of the sperm cells. Flow cytometry and fluorescence in-situ hybridization (FISH) were shown to supplement routine semen analysis by providing information on the sperm chromatin. Using flow cytometry, propidium iodide-stained spermatozoa from the same sperm sample were compared with a normal reference pool, and with human lymphocytes. The results point to a population of diploid sperm cells rather than to mature haploid spermatozoa. Numerical chromosomal abnormalities of the spermatozoa were subsequently evaluated using FISH. A total of 1000 sperm cells were scored for X and Y chromosomes, and an additional 1128 sperm cells for chromosome 18. Aneuploidy of chromosomes X and Y was revealed in 96.9% of the cells and of chromosome 18 in 90.3% of the cells. Non-disjunction of chromosome X and Y in meiosis I and II occurred in 54.8 and 2.7% of the sperm cells respectively. Non-disjunction in both meiosis I and II occurred in 39.4% of the sperm cells. A normal haploid pattern for chromosomes X and Y was observed in only 3.1%, and for chromosome 18 in 9.7%, of the cells. Using three colour FISH for the sex chromosomes and for chromosome 18, diploidy was demonstrated in 19.4% of 500 sperm cells and aneuploidy in virtually all sperm cells (99.2%). The use of flow cytometry and FISH in cases where genetic and developmental chromatin abnormalities are suspected is a valuable adjunct to other available techniques, and can guide the clinicians to decide which samples are unsuitable for intracytoplasmic injection.

  1. Turbidity as a method of preparing sperm dilutions in the echinoid sperm/egg bioassay

    SciTech Connect

    Hall, T.J.; Haley, R.K.; Battan, K.J. )

    1993-11-01

    The use of turbidimeter for preparing sperm dilutions used in the echinoid sperm/egg bioassay was evaluated. Regression analyses of the relationship between sperm density and turbidity for the sea urchins Strongylocentrotus purpuratus and Strongylocentrotus droebachiensis and the sand dollar Dendraster excentricus indicated that although there were slope differences for each species, each coefficient of determination was highly significant. For Dendraster excentricus, triplicate hemacytometer counts over a range of turbidities as well as repeated preparations of a single sperm turbidity indicated similar variability for each. The use of the turbidimeter has time-saving advantages over conventional hemacytometer methods without sacrificing precision. Sperm dilutions can be prepared rapidly, minimizing seawater sperm preactivation before test initiation, and may therefore contribute to increased test precision.

  2. Site of Mammalian Sperm Acrosome Reaction.

    PubMed

    Hirohashi, Noritaka

    2016-01-01

    Until recently, no special attention has been paid to the question of the site of mammalian sperm acrosome reaction (AR) in the female reproductive tract. Because AR is an essential process that enables the spermatozoon to fertilize, it is generally believed that it occurs at a specific step during sperm-egg interaction. It is generally thought that "the site of action coincides with the site of commitment." Thus, understanding the roles of AR and acrosomal substances is needed to gain insight into the site of the sperm commitment to undergo AR. PMID:27194354

  3. Sperm DNA fragmentation and base oxidation.

    PubMed

    Lewis, Sheena E M

    2014-01-01

    Sperm DNA damage has been shown to be a valuable diagnostic and prognostic biomarker for male infertility and assisted reproductive treatment (ART) outcome. It is linked to every fertility checkpoint from reduced fertilization rates, lower embryo quality and pregnancy rates to higher rates of spontaneous miscarriage and childhood diseases. It is more robust than conventional semen parameters.The aim of this chapter is to provide an overview of current laboratory tests and relationships between sperm DNA damage and clinical outcomes. The conclusion is that sperm DNA damage is an important indicator of semen quality, and its routine use in the fertility clinic would improve ART success rates. PMID:23955675

  4. Ovarian Fluid Mediates the Temporal Decline in Sperm Viability in a Fish with Sperm Storage

    PubMed Central

    Gasparini, Clelia; Evans, Jonathan P.

    2013-01-01

    A loss of sperm viability and functionality during sperm transfer and storage within the female reproductive tract can have important fitness implications by disrupting fertilization and impairing offspring development and survival. Consequently, mechanisms that mitigate the temporal decline in sperm function are likely to be important targets of selection. In many species, ovarian fluid is known to regulate and maintain sperm quality. In this paper, we use the guppy Poecilia reticulata, a highly polyandrous freshwater fish exhibiting internal fertilization and sperm storage, to determine whether ovarian fluid (OF) influences the decline in sperm viability (the proportion of live sperm in the ejaculate) over time and whether any observed effects depend on male sexual ornamentation. To address these questions we used a paired experimental design in which ejaculates from individual males were tested in vitro both in presence and absence of OF. Our results revealed that the temporal decline in sperm viability was significantly reduced in the presence of OF compared to a saline control. This finding raises the intriguing possibility that OF may play a role in mediating the decline in sperm quality due to the deleterious effects of sperm ageing, although other possible explanations for this observation are discussed. Interestingly, we also show that the age-related decline in sperm viability was contingent on male sexual ornamentation; males with relatively high levels of iridescence (indicating higher sexual attractiveness) exhibited a more pronounced decline in sperm viability over time than their less ornamented counterparts. This latter finding offers possible insights into the functional basis for the previously observed trade-off between these key components of pre- and postcopulatory sexual selection. PMID:23691216

  5. Safety of intracytoplasmic sperm injection.

    PubMed

    Palermo, Gianpiero D; Neri, Queenie V; Rosenwaks, Zev

    2014-01-01

    Early follow-up studies of IVF children showed that the frequency of birth anomalies resembled those arising with natural conception. More detailed analyses confirmed these findings, reinforcing the concept of the preimplantation period as teratologically "safe." The use of intracytoplasmic sperm injection (ICSI) to achieve fertilization introduced another variable.ICSI's safety has often been criticized because the fertilizing spermatozoon neither binds to the zona pellucida nor fuses with oolemma. Bypassing these physiologic steps together with the arbitrary selection of the spermatozoon has been reason for concern. Thus far, ICSI offspring undergoing adolescence and beyond has provided sufficient information to reassure these qualms. In fact, the health of the offspring generated through ICSI, once taken into consideration the gestational order, the age and the genetic makeup of the couples are generally reassuring.

  6. Computer-assisted sperm analysis parameters in young fertile sperm donors and relationship with age.

    PubMed

    Fréour, Thomas; Jean, Miguel; Mirallie, Sophie; Barriere, Paul

    2012-04-01

    Sperm parameter values have been shown to decline with age, according to conventional sperm analysis. However, the effect of age on sperm kinematic parameters has been rarely studied, especially in young fertile men. Here, we studied Computer-Assisted Sperm Analysis (CASA) parameters in a large cohort of men with proven fertility, in order to determine if there is a decline with age in this young fertile population. This retrospective analysis of CASA parameters was conducted on all donors included in the sperm donor programme in the Assisted Reproductive Techniques (ART) Centre of the University Hospital of Nantes between 2006 and 2009. Sperm concentration, motility, and kinetic parameters were recorded by a HTM-Ceros system and compared in 3 groups of sperm donors according to their age: <35 years, 36-40 years, and 41-44 years. A total of 362 ejaculates from 138 donors were analyzed. Values for ALH, VCL, LIN, and STR significantly decreased with age. Sperm concentration, motile sperm proportion, and other kinetic parameters did not differ significantly among the groups. The use of CASA allowed the identification of ALH, VCL, LIN, and STR age-related decrease in young men with proven fertility.

  7. Motile sperm organelle morphology examination (MSOME) and sperm head vacuoles: state of the art in 2013.

    PubMed

    Perdrix, Anne; Rives, Nathalie

    2013-01-01

    BACKGROUND Approximately 10 years after the first publication introducing the motile sperm organelle morphology examination (MSOME), many questions remained about sperm vacuoles: frequency, size, localization, mode of occurrence, biological significance and impact on male fertility potential. Many studies have tried to characterize sperm vacuoles, to determine the sperm abnormalities possibly associated with vacuoles, to test the diagnostic value of MSOME for male infertility or to question the benefits of intracytoplasmic morphologically selected sperm injection (IMSI). METHODS We searched PubMed for articles in the English language published in 2001-2012 regarding human sperm head vacuoles, MSOME and IMSI. RESULTS A bibliographic analysis revealed consensus for the following findings: (i) sperm vacuoles appeared frequently, often multiple and preferentially anterior; (ii) sperm vacuoles and sperm chromatin immaturity have been associated, particularly in the case of large vacuoles; (iii) teratozoospermia was a preferred indication of MSOME and IMSI. CONCLUSION The high-magnification system appears to be a powerful method to improve our understanding of human spermatozoa. However, its clinical use remains unclear in the fields of male infertility diagnosis and assisted reproduction techniques (ARTs).

  8. Female sperm use and storage between fertilization events drive sperm competition and male ejaculate allocation.

    PubMed

    Requena, Gustavo S; Alonzo, Suzanne H

    2014-12-01

    Sperm competition theory has traditionally focused on how male allocation responds to female promiscuity, when males compete to fertilize a single clutch of eggs. Here, we develop a model to ask how female sperm use and storage across consecutive reproductive events affect male ejaculate allocation and patterns of mating and paternity. In our model, sperm use (a single parameter under female control) is the main determinant of sperm competition, which alters the effect of female promiscuity on male success and, ultimately, male reproductive allocation. Our theory reproduces the general pattern predicted by existing theory that increased sperm competition favors increased allocation to ejaculates. However, our model predicts a negative correlation between male ejaculate allocation and female promiscuity, challenging the generality of a prevailing expectation of sperm competition theory. Early models assumed that the energetic costs of precopulatory competition and the level of sperm competition are both determined by female promiscuity, which leads to an assumed covariation between these two processes. By modeling precopulatory costs and sperm competition independently, our theoretical framework allows us to examine how male allocation should respond independently to variation in sperm competition and energetic trade-offs in mating systems that have been overlooked in the past.

  9. Lactic acid is a sperm motility inactivation factor in the sperm storage tubules

    PubMed Central

    Matsuzaki, Mei; Mizushima, Shusei; Hiyama, Gen; Hirohashi, Noritaka; Shiba, Kogiku; Inaba, Kazuo; Suzuki, Tomohiro; Dohra, Hideo; Ohnishi, Toshiyuki; Sato, Yoshikatsu; Kohsaka, Tetsuya; Ichikawa, Yoshinobu; Atsumi, Yusuke; Yoshimura, Takashi; Sasanami, Tomohiro

    2015-01-01

    Although successful fertilization depends on timely encounters between sperm and egg, the decoupling of mating and fertilization often confers reproductive advantages to internally fertilizing animals. In several vertebrate groups, postcopulatory sperm viability is prolonged by storage in specialized organs within the female reproductive tract. In birds, ejaculated sperm can be stored in a quiescent state within oviductal sperm storage tubules (SSTs), thereby retaining fertilizability for up to 15 weeks at body temperature (41 °C); however, the mechanism by which motile sperm become quiescent within SSTs is unknown. Here, we show that low oxygen and high lactic acid concentrations are established in quail SSTs. Flagellar quiescence was induced by lactic acid in the concentration range found in SSTs through flagellar dynein ATPase inactivation following cytoplasmic acidification (sperm morphology under hypoxic and high temperature conditions indicates that a combination of these factors enables sperm cells to survive during the ovulation cycles. Our findings suggested a novel physiological role for lactic acid in promoting sperm quiescence in SSTs and opened up a new opportunity for technological improvement in prolonging sperm longevity at ambient or body temperature. PMID:26619826

  10. The limitations of in vitro fertilization from males with severe oligospermia and abnormal sperm morphology.

    PubMed

    Yovich, J L; Stanger, J D

    1984-09-01

    Thirty-one patients whose infertility was attributed to oligospermia were included for treatment by in vitro fertilization and embryo transfer. Three subgroups were defined: severe oligospermia (less than or equal to 5 million motile sperm/ml), moderate oligospermia (6 to less than 12 million motile sperm/ml), and abnormal sperm morphology (greater than 60% atypical). The fertilization rates were compared to those of a normospermic group managed concurrently. A modified overlay technique of sperm preparation is described for oligospermic samples so that the number of motile spermatozoa inseminated into each tube or culture dish containing a mature preovulatory oocyte was similar in each category, within the range 0.5 to 2 X 10(5)/ml. Significantly fewer oocytes were fertilized in the severe oligospermic group (P less than 0.001), suggesting a reduced capacity for fertilization by spermatozoa from severely oligospermic males. The fertilization rate of oocytes was normal in the moderate oligospermic group and those with abnormal morphology, although in the latter there was a significant delay noted in reaching the pronuclear stage (P less than 0.001), and the embryos were at a less advanced stage of cleavage at the time of transfer (0.001 less than P less than 0.01). Pregnancies were achieved in both the severe and the moderate oligospermic groups, with healthy infants delivered from each.

  11. Widespread Epigenetic Abnormalities Suggest a Broad DNA Methylation Erasure Defect in Abnormal Human Sperm

    PubMed Central

    Siegmund, Kimberly; Yang, Allen; Laird, Peter W.; Sokol, Rebecca Z.

    2007-01-01

    Background Male-factor infertility is a common condition, and etiology is unknown for a high proportion of cases. Abnormal epigenetic programming of the germline is proposed as a possible mechanism compromising spermatogenesis of some men currently diagnosed with idiopathic infertility. During germ cell maturation and gametogenesis, cells of the germ line undergo extensive epigenetic reprogramming. This process involves widespread erasure of somatic-like patterns of DNA methylation followed by establishment of sex-specific patterns by de novo DNA methylation. Incomplete reprogramming of the male germ line could, in theory, result in both altered sperm DNA methylation and compromised spermatogenesis. Methodology/Principal Finding We determined concentration, motility and morphology of sperm in semen samples collected by male members of couples attending an infertility clinic. Using MethyLight and Illumina assays we measured methylation of DNA isolated from purified sperm from the same samples. Methylation at numerous sequences was elevated in DNA from poor quality sperm. Conclusions This is the first report of a broad epigenetic defect associated with abnormal semen parameters. Our results suggest that the underlying mechanism for these epigenetic changes may be improper erasure of DNA methylation during epigenetic reprogramming of the male germ line. PMID:18074014

  12. Heat shock suppresses mating and sperm transfer in the rice leaf folder Cnaphalocrocis medinalis.

    PubMed

    Liao, H J; Qian, Q; Liu, X D

    2014-06-01

    Temperature is a key environmental factor in determining the population size of Cnaphalocrocis medinalis in summer. High temperatures inhibit survival, development and fecundity of this insect. However, biological responses of female and male adults to heat shock, and physiological mechanism of high temperature suppressing population development are still ambiguous. We experimentally tested the impact of heat shock (5 h day-1) on biological traits, spermatogenesis and sperm transfer of adults of C. medinalis. The result showed that heat exposure to 39 and 40 °C for 5 h reduced longevity and copulation frequency of adults, and hatchability of eggs. Immediate survival rate of males was lower than that of females after 3 days of exposure to 41 °C. The oviposition period, copulation frequency, fecundity of adults and hatchability of eggs were significantly lower when male adults were exposed to 40 or 41 °C for 3 days. Heat shock decreased frequency and success rate of mating when males were exposed, and it also resulted in postponement of mating behaviour and prolongation of mating duration as both the female and male adults were exposed. Heat shock did not affect spermatogenesis, but significantly inhibited sperms maturation. Moreover, males could not ejaculate sperm into females during copulation when these male moths received heat shock. Heat shock remarkably suppressed mating behaviour and sperm transfer, which led to a dramatic decline of rice leaf folder populations.

  13. Participation of the sperm proteasome during in vitro fertilisation and the acrosome reaction in cattle.

    PubMed

    Sánchez, R; Deppe, M; Schulz, M; Bravo, P; Villegas, J; Morales, P; Risopatrón, J

    2011-04-01

    In this work, we have investigated the role of the bovine sperm proteasome during in vitro fertilisation (IVF) and the acrosome reaction (AR). Motile spermatozoa, obtained by a swim-up method in Sperm-Talp medium, were capacitated for 3.5 h and incubated in the presence or absence of the specific proteasome inhibitor epoxomicin for 30 and 60 min. Then, the spermatozoa were co-incubated with mature bovine cumulus oocytes and after 48 h the cleavage rate of inseminated oocytes was evaluated. In addition, we evaluated the participation of the sperm proteasome during the progesterone-induced AR. Capacitated spermatozoa were incubated for 30 min with or without epoxomicin, then progesterone was added and the ARs were evaluated using the dual fluorescent staining technique 'Hoechst and chlortetracycline'. The results indicate that the proteasome inhibitor decreased the cleavage rate of oocytes inseminated with treated spermatozoa. In addition, acrosomal exocytosis levels were statistically significantly higher in the samples treated with the AR inducer progesterone than in control samples in the absence of the inducer. However, the progesterone-induced AR was significantly reduced by previous treatment of the spermatozoa with epoxomicin (P < 0.001). These observations indicate that the bovine sperm proteasome participates in the IVF and AR processes.

  14. Sperm motility activation, sperm heterogeneity and sperm-female tract interactions in Bennett's wallaby (Macropus rufogriseus rufogriseus).

    PubMed

    Boere, Janneke; Díaz, Daniela Esteban; Holt, William V

    2011-01-01

    Sperm-oviduct interactions in Bennett's wallaby (Macropus rufogriseus rufogriseus) were investigated using in vitro cocultures of cauda epididymal spermatozoa and oviducal epithelial cells. Kidney epithelial cells were used as non-reproductive control tissues. Spermatozoa attached to epithelial cells of both origins, but sperm survival and activity was higher when cocultured with oviducal cells. New findings during live sperm-epithelial interactions included: (1) a high frequency of reversible head movements, from linear (streamlined configuration) to T shape (thumbtack configuration) in swimming spermatozoa immediately after the start of coculture; (2) the loss of sperm tails (tail shedding) increasing with time; and (3) interrupted swimming patterns, where periods of fast movement were interspersed with slower swimming while the spermatozoa interacted with the epithelial cell surface. Sperm motility activation responses were characterised after diluting the epididymal samples in phosphate-buffered saline, medium M199 and Tyrode's medium. The results confirmed that the marsupial oviduct is able to support the viability and motility of a sperm subpopulation for at least 20 h in vitro and suggest that some spermatozoa shed their tails after binding, possibly as a result of a selective process. PMID:21557927

  15. Production of diabetic offspring using cryopreserved epididymal sperm by in vitro fertilization and intrafallopian insemination techniques in transgenic pigs.

    PubMed

    Umeyama, Kazuhiro; Honda, Kasumi; Matsunari, Hitomi; Nakano, Kazuaki; Hidaka, Tatsuro; Sekiguchi, Keito; Mochizuki, Hironori; Takeuchi, Yasuhiro; Fujiwara, Tsukasa; Watanabe, Masahito; Nagaya, Masaki; Nagashima, Hiroshi

    2013-12-17

    Somatic cell nuclear transfer (SCNT) is a useful technique for creating pig strains that model human diseases. However, production of numerous cloned disease model pigs by SCNT for large-scale experiments is impractical due to its complexity and inefficiency. In the present study, we aimed to establish an efficient procedure for proliferating the diabetes model pig carrying the mutant human hepatocyte nuclear factor-1α gene. A founder diabetes transgenic cloned pig was generated by SCNT and treated with insulin to allow for normal growth to maturity, at which point epididymal sperm could be collected for cryopreservation. In vitro fertilization and intrafallopian insemination using the cryopreserved epididymal sperm resulted in diabetes model transgenic offspring. These results suggest that artificial reproductive technology using cryopreserved epididymal sperm could be a practical option for proliferation of genetically modified disease model pigs. PMID:23979397

  16. Production of Diabetic Offspring Using Cryopreserved Epididymal Sperm by In Vitro Fertilization and Intrafallopian Insemination Techniques in Transgenic Pigs

    PubMed Central

    UMEYAMA, Kazuhiro; HONDA, Kasumi; MATSUNARI, Hitomi; NAKANO, Kazuaki; HIDAKA, Tatsuro; SEKIGUCHI, Keito; MOCHIZUKI, Hironori; TAKEUCHI, Yasuhiro; FUJIWARA, Tsukasa; WATANABE, Masahito; NAGAYA, Masaki; NAGASHIMA, Hiroshi

    2013-01-01

    Abstract Somatic cell nuclear transfer (SCNT) is a useful technique for creating pig strains that model human diseases. However, production of numerous cloned disease model pigs by SCNT for large-scale experiments is impractical due to its complexity and inefficiency. In the present study, we aimed to establish an efficient procedure for proliferating the diabetes model pig carrying the mutant human hepatocyte nuclear factor-1α gene. A founder diabetes transgenic cloned pig was generated by SCNT and treated with insulin to allow for normal growth to maturity, at which point epididymal sperm could be collected for cryopreservation. In vitro fertilization and intrafallopian insemination using the cryopreserved epididymal sperm resulted in diabetes model transgenic offspring. These results suggest that artificial reproductive technology using cryopreserved epididymal sperm could be a practical option for proliferation of genetically modified disease model pigs. PMID:23979397

  17. Mouse Y-Encoded Transcription Factor Zfy2 Is Essential for Sperm Formation and Function in Assisted Fertilization

    PubMed Central

    Yamauchi, Yasuhiro; Riel, Jonathan M.; Ruthig, Victor; Ward, Monika A.

    2015-01-01

    Abstract Spermatogenesis is a key developmental process allowing for a formation of a mature male gamete. During its final phase, spermiogenesis, haploid round spermatids undergo cellular differentiation into spermatozoa, which involves extensive restructuring of cell morphology, DNA, and epigenome. Using mouse models with abrogated Y chromosome gene complements and Y-derived transgene we identified Y chromosome encoded Zfy2 as the gene responsible for sperm formation and function. In the presence of a Zfy2 transgene, mice lacking the Y chromosome and transgenic for two other Y-derived genes, Sry driving sex determination and Eif2s3y initiating spermatogenesis, are capable of producing sperm which when injected into the oocytes yield live offspring. Therefore, only three Y chromosome genes, Sry, Eif2s3y and Zfy2, constitute the minimum Y chromosome complement compatible with successful intracytoplasmic sperm injection in the mouse. PMID:26719889

  18. A microtubule organizing centre (MTOC) is responsible for the production of the sperm flagellum in Matsucoccus feytaudi (Hemiptera: Coccoidea).

    PubMed

    Paoli, Francesco; Roversi, Pio Federico; Gottardo, Marco; Callaini, Giuliano; Mercati, David; Dallai, Romano

    2015-05-01

    A microtubule organizing centre (MTOC) has been described in the spermatid of the hemipteran Matsucoccus feytaudi (Coccoidea). This structure, revealed as a fluorescent ring by treatment with γ-tubulin antibody, gives rise to a bundle of microtubules which surrounds the elongated cylindrical nucleus. This microtubule bundle has been considered an atypical sperm flagellum provided with sperm motility. A comparison of the M. feytaudi MTOC with the material associated with the centriole of Drosophila melanogaster spermatids confirms the great similarity between the two structures, both involved in the nucleation of microtubules. Like the D. melanogaster material associated with the centriole, the M. feytaudi MTOC is a transient structure which disappears or degenerates at the end of spermiogenesis and is no longer visible in the mature sperm.

  19. Comparative evolutionary psychology of sperm competition.

    PubMed

    Shackelford, Todd K; Goetz, Aaron T

    2006-05-01

    A comparative evolutionary psychological perspective predicts that species that recurrently faced similar adaptive problems may have evolved similar psychological mechanisms to solve these problems. Sperm competition provides an arena in which to assess the heuristic value of such a comparative evolutionary perspective. The sperm competition that results from female infidelity and polyandry presents a similar class of adaptive problems for individuals across many species. The authors first describe mechanisms of sperm competition in insects and in birds. They suggest that the adaptive problems and evolved solutions in these species provide insight into human anatomy, physiology, psychology, and behavior. The authors then review recent theoretical and empirical arguments for the existence of sperm competition in humans and discuss proposed adaptations in humans that have analogs in insects or birds. The authors conclude by highlighting the heuristic value of a comparative evolutionary psychological approach in this field.

  20. Sperm macromolecules associated with bull fertility.

    PubMed

    Kaya, Abdullah; Memili, Erdoğan

    2016-06-01

    Bull fertility, ability of the sperm to fertilize and activate the egg that sustain embryo development, is vitally important for effective and efficient production of cattle. Fertility is a complex trait with low heritability. Despite recent advances in genomic selection and possibility of enormous paternal benefits to profitable cattle production, there exist no reliable tests for evaluating semen quality and predicting bull fertility. This review focuses on sperm macromolecules such as transcripts, proteins and the epigenome, i.e., the functional genome that are associated with bull fertility. Generating new information in these systems is important beyond agriculture because such progress advances the fundamental science of the mammalian male gamete while at the same time introduces biotechnology into livestock production. Sperm macromolecules and epigenome markers associated with bull fertility can be used alone or in combination with the current SNP microarrays to determine sperm quality and to indicate bull fertility.

  1. Mammalian Sperm Motility: Observation and Theory

    NASA Astrophysics Data System (ADS)

    Gaffney, E. A.; Gadêlha, H.; Smith, D. J.; Blake, J. R.; Kirkman-Brown, J. C.

    2011-01-01

    Mammalian spermatozoa motility is a subject of growing importance because of rising human infertility and the possibility of improving animal breeding. We highlight opportunities for fluid and continuum dynamics to provide novel insights concerning the mechanics of these specialized cells, especially during their remarkable journey to the egg. The biological structure of the motile sperm appendage, the flagellum, is described and placed in the context of the mechanics underlying the migration of mammalian sperm through the numerous environments of the female reproductive tract. This process demands certain specific changes to flagellar movement and motility for which further mechanical insight would be valuable, although this requires improved modeling capabilities, particularly to increase our understanding of sperm progression in vivo. We summarize current theoretical studies, highlighting the synergistic combination of imaging and theory in exploring sperm motility, and discuss the challenges for future observational and theoretical studies in understanding the underlying mechanics.

  2. Sperm Shape (Morphology): Does It Affect Fertility?

    MedlinePlus

    ... decide whether a couple should use in vitro fertilization (IVF) to attempt a pregnancy. It is best ... genetic material. Once the sperm enters the egg, fertilization has a good chance of taking place. However, ...

  3. Rat sperm motility analysis: methodologic considerations

    EPA Science Inventory

    The objective of these studies was to optimize conditions for computer-assisted sperm analysis (CASA) of rat epididymal spermatozoa. Methodologic issues addressed include sample collection technique, sampling region within the epididymis, type of diluent medium used, and sample c...

  4. Cryopreservation increases coating of bull sperm by seminal plasma binder of sperm proteins BSP1, BSP3, and BSP5.

    PubMed

    Ardon, Florencia; Suarez, Susan S

    2013-08-01

    Artificial insemination with frozen semen allows affordable, worldwide dissemination of gametes with superior genetics. Nevertheless, sperm are damaged by the cryopreservation process. Elucidating the molecular effects of cryopreservation on sperm could suggest methods for improving fertility of frozen/thawed semen. This study was undertaken to examine the effect of cryopreservation on the coating of sperm by binder of sperm (BSP) proteins in seminal plasma. BSP proteins are secreted by the seminal vesicles and coat the surface of sperm by partially intercalating into the outer leaflet of the sperm plasma membrane. The BSP proteins are known to play roles in the formation of the oviductal sperm storage reservoir and in sperm capacitation. We investigated the effects of cryopreservation on the sperm BSP protein coat using Bovipure to separate live sperm from extended semen and then assaying the amounts of BSP proteins on sperm using quantitative western blotting with custom-made antibodies against unique sequences of each BSP protein. Greater amounts of all three BSP proteins (BSP1, BSP3, and BSP5) were detected on frozen/thawed sperm than on fresh sperm. Furthermore, the reduction of BSP3 from 15 to 13 kDa in mass, which occurs during incubation of sperm under mild capacitating conditions, was enhanced by cryopreservation. We concluded that freezing alters the BSP protein coating on sperm, which could account in part for reduced fertility of cryopreserved semen samples.

  5. The effect of polymer dots on bioactivity of mouse sperm in vitro

    NASA Astrophysics Data System (ADS)

    Feng, Gang; Chen, Qiang; Zhai, Peng; Wang, Xiaomei; Lin, Guimiao; Xu, Gaixia; Chen, Danni

    2014-09-01

    Objective: In recent years, semiconducting polymer dots (Pdots)have caught considerable attention for their outstanding optical characteristics in biomedical imaging applications. Not as semiconductor quantum dots, Pdots are composed of nonmetallic material and their biological effects remain unclear. In this work, we investigated the effects of a band new polymer dots on bioactivity of mouse sperm using a computer-aided sperm analysis system(CASA) and an in vitro fertilization (IVF) model. Methods: The semiconducting polymer dots used in this study is CN-PPV Pdots, which emits in the orange wavelength range with high brightness. Epididymal mouse sperm were collected from 7-8weeks old Balb/c mouse. Firstly, CN-PPV Pdots was added into the Human Tubal Fluid (HTF) media at various concentrations (0, 1, 10, 100 nmol/L respectively ), then sperm bioactivity and vitality were evaluated every 10 minutes. Secondly, the treated sperm were co-cultured with matured oocytes in HTF media, fertilization rate and oocytes development were recorded after 24 hours co-incubation. Results: Sperm viability in the control group (0 nmol/L) and experimental group (1, 10,100 nmol/L) were 57.20+/-4.51%, 58.17+/-4.81%, 55.50+/-4.52%, 46.26%+/-3.83%, respectively. Fertilization rate in different groups showed no obvious differences, control group (0 nmol/L) and experimental group (1, 10, 100 nmol/L) were 38.75+/-1.71%, 37.01+/-4.69%, 32.75+/-1.71%, 35.24+/-2.37%, respectively. Conclusion: Our data indicated that the CN-PPV Pdots had a very high biocompatibility on sperm in both the activation and the IVF process, even in extreme high Pdots concentration,the sperm bioactivity only got slight restrained. The effect of CN-PPV Pdots seems has no or little toxicity,and the long-term embryonic development has yet to be verified.

  6. Sperm DNA oxidative damage and DNA adducts.

    PubMed

    Jeng, Hueiwang Anna; Pan, Chih-Hong; Chao, Mu-Rong; Lin, Wen-Yi

    2015-12-01

    The objective of this study was to investigate DNA damage and adducts in sperm from coke oven workers who have been exposed to polycyclic aromatic hydrocarbons. A longitudinal study was conducted with repeated measurements during spermatogenesis. Coke-oven workers (n=112) from a coke-oven plant served the PAH-exposed group, while administrators and security personnel (n=67) served the control. Routine semen parameters (concentration, motility, vitality, and morphology) were analyzed simultaneously; the assessment of sperm DNA integrity endpoints included DNA fragmentation, bulky DNA adducts, and 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxo-dGuo). The degree of sperm DNA fragmentation was measured using the terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) assay and sperm chromatin structure assay (SCSA). The PAH-exposed group had a significant increase in bulky DNA adducts and 8-oxo-dGuo compared to the control subjects (Ps=0.002 and 0.045, respectively). Coke oven workers' percentages of DNA fragmentation and denaturation from the PAH-exposed group were not significantly different from those of the control subjects (Ps=0.232 and 0.245, respectively). Routine semen parameters and DNA integrity endpoints were not correlated. Concentrations of 8-oxo-dGuo were positively correlated with percentages of DNA fragmentation measured by both TUNEL and SCSA (Ps=0.045 and 0.034, respectively). However, the concentrations of 8-oxo-dGuo and percentages of DNA fragmentation did not correlate with concentrations of bulky DNA adducts. In summary, coke oven workers with chronic exposure to PAHs experienced decreased sperm DNA integrity. Oxidative stress could contribute to the degree of DNA fragmentation. Bulky DNA adducts may be independent of the formation of DNA fragmentation and oxidative adducts in sperm. Monitoring sperm DNA integrity is recommended as a part of the process of assessing the impact of occupational and environmental toxins on sperm.

  7. Membrane hyperpolarization during human sperm capacitation

    PubMed Central

    López-González, I.; Torres-Rodríguez, P.; Sánchez-Carranza, O.; Solís-López, A.; Santi, C.M.; Darszon, A.; Treviño, C.L.

    2014-01-01

    Sperm capacitation is a complex and indispensable physiological process that spermatozoa must undergo in order to acquire fertilization capability. Spermatozoa from several mammalian species, including mice, exhibit a capacitation-associated plasma membrane hyperpolarization, which is necessary for the acrosome reaction to occur. Despite its importance, this hyperpolarization event has not been adequately examined in human sperm. In this report we used flow cytometry to show that a subpopulation of human sperm indeed undergo a plasma membrane hyperpolarization upon in vitro capacitation. This hyperpolarization correlated with two other well-characterized capacitation parameters, namely an increase in intracellular pH and Ca2+ concentration, measured also by flow cytometry. We found that sperm membrane hyperpolarization was completely abolished in the presence of a high external K+ concentration (60 mM), indicating the participation of K+ channels. In order to identify, which of the potential K+ channels were involved in this hyperpolarization, we used different K+ channel inhibitors including charybdotoxin, slotoxin and iberiotoxin (which target Slo1) and clofilium (a more specific blocker for Slo3). All these K+ channel antagonists inhibited membrane hyperpolarization to a similar extent, suggesting that both members of the Slo family may potentially participate. Two very recent papers recorded K+ currents in human sperm electrophysiologically, with some contradictory results. In the present work, we show through immunoblotting that Slo3 channels are present in the human sperm membrane. In addition, we found that human Slo3 channels expressed in CHO cells were sensitive to clofilium (50 μM). Considered altogether, our data indicate that Slo1 and Slo3 could share the preponderant role in the capacitation-associated hyperpolarization of human sperm in contrast to what has been previously reported for mouse sperm, where Slo3 channels are the main contributors to the

  8. Sperm DNA oxidative damage and DNA adducts.

    PubMed

    Jeng, Hueiwang Anna; Pan, Chih-Hong; Chao, Mu-Rong; Lin, Wen-Yi

    2015-12-01

    The objective of this study was to investigate DNA damage and adducts in sperm from coke oven workers who have been exposed to polycyclic aromatic hydrocarbons. A longitudinal study was conducted with repeated measurements during spermatogenesis. Coke-oven workers (n=112) from a coke-oven plant served the PAH-exposed group, while administrators and security personnel (n=67) served the control. Routine semen parameters (concentration, motility, vitality, and morphology) were analyzed simultaneously; the assessment of sperm DNA integrity endpoints included DNA fragmentation, bulky DNA adducts, and 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxo-dGuo). The degree of sperm DNA fragmentation was measured using the terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) assay and sperm chromatin structure assay (SCSA). The PAH-exposed group had a significant increase in bulky DNA adducts and 8-oxo-dGuo compared to the control subjects (Ps=0.002 and 0.045, respectively). Coke oven workers' percentages of DNA fragmentation and denaturation from the PAH-exposed group were not significantly different from those of the control subjects (Ps=0.232 and 0.245, respectively). Routine semen parameters and DNA integrity endpoints were not correlated. Concentrations of 8-oxo-dGuo were positively correlated with percentages of DNA fragmentation measured by both TUNEL and SCSA (Ps=0.045 and 0.034, respectively). However, the concentrations of 8-oxo-dGuo and percentages of DNA fragmentation did not correlate with concentrations of bulky DNA adducts. In summary, coke oven workers with chronic exposure to PAHs experienced decreased sperm DNA integrity. Oxidative stress could contribute to the degree of DNA fragmentation. Bulky DNA adducts may be independent of the formation of DNA fragmentation and oxidative adducts in sperm. Monitoring sperm DNA integrity is recommended as a part of the process of assessing the impact of occupational and environmental toxins on sperm

  9. Membrane hyperpolarization during human sperm capacitation.

    PubMed

    López-González, I; Torres-Rodríguez, P; Sánchez-Carranza, O; Solís-López, A; Santi, C M; Darszon, A; Treviño, C L

    2014-07-01

    Sperm capacitation is a complex and indispensable physiological process that spermatozoa must undergo in order to acquire fertilization capability. Spermatozoa from several mammalian species, including mice, exhibit a capacitation-associated plasma membrane hyperpolarization, which is necessary for the acrosome reaction to occur. Despite its importance, this hyperpolarization event has not been adequately examined in human sperm. In this report we used flow cytometry to show that a subpopulation of human sperm indeed undergo a plasma membrane hyperpolarization upon in vitro capacitation. This hyperpolarization correlated with two other well-characterized capacitation parameters, namely an increase in intracellular pH and Ca(2+) concentration, measured also by flow cytometry. We found that sperm membrane hyperpolarization was completely abolished in the presence of a high external K(+) concentration (60 mM), indicating the participation of K(+) channels. In order to identify, which of the potential K(+) channels were involved in this hyperpolarization, we used different K(+) channel inhibitors including charybdotoxin, slotoxin and iberiotoxin (which target Slo1) and clofilium (a more specific blocker for Slo3). All these K(+) channel antagonists inhibited membrane hyperpolarization to a similar extent, suggesting that both members of the Slo family may potentially participate. Two very recent papers recorded K(+) currents in human sperm electrophysiologically, with some contradictory results. In the present work, we show through immunoblotting that Slo3 channels are present in the human sperm membrane. In addition, we found that human Slo3 channels expressed in CHO cells were sensitive to clofilium (50 μM). Considered altogether, our data indicate that Slo1 and Slo3 could share the preponderant role in the capacitation-associated hyperpolarization of human sperm in contrast to what has been previously reported for mouse sperm, where Slo3 channels are the main

  10. Effect of melatonin on maturation capacity and fertilization of Nili-Ravi buffalo (Bubalus bubalis) oocytes

    PubMed Central

    Nagina, G.; Asima, A.; Nemat, U.; Shamim, A.

    2016-01-01

    This study evaluated the effect of melatonin supplementation of in vitro maturation media on in vitro maturation (IVM) and in vitro fertilization (IVF) rate of buffalo oocytes. Cumulus oocytes complexes (COCs) were aspirated from follicles of 2-8 mm diameter. In experiment I, COCs were matured in IVM medium supplemented with 0 (control), 250, 500, and 1000 μM melatonin for 22-24 hours in CO2 incubator at 38.5°C with 5% CO2 and at 95% relative humidity. The maturation rate did not differ in media supplemented with melatonin at 250 μM, 500 μM, 1000 μM and control (0 μM). In experiment II, the matured oocytes were fertilized in 50 μl droplets of Tyrode’s Albumin Lactate Pyruvate (TALP) medium having 10 ug/ml heparin for sperm (2 million/ml) capacitation. The fertilization droplets were then kept for incubation at 5% CO2, 39°C and at 95% relative humidity for 18 hours. The fertilization rate was assessed by sperm penetration and pronuclear formation. Fertilization rate was improved when maturation medium was supplemented with 250 μM melatonin compared to control. In conclusion, melatonin supplementation to serum free maturation media at 250 μM improved the fertilization rate of buffalo oocytes. PMID:27540514

  11. Quantification of adenosine triphosphate, adenosine diphosphate, and creatine phosphate in sterlet spermatozoa during maturation.

    PubMed

    Fedorov, P; Dzyuba, B; Fedorova, G; Grabic, R; Cosson, J; Rodina, M

    2015-11-01

    Sturgeon spermatozoa maturation during their passage through the kidney is a prerequisite for initiation of motility. Samples of sterlet () testicular sperm (TS) were matured in vitro by incubation in seminal fluid (SF) or in SF supplemented with carbonyl cyanide -chlorophenyl hydrazone (CCCP; a respiration uncoupling agent). Sperm was diluted in activation medium (AM) containing 10 m Tris-HCl buffer (pH 8.5) and 0.25% Pluronic, and spermatozoon motility was assessed. Samples were taken and fixed in 3 perchloric acid at 3 points in the incubation process. Quantification of ATP, ADP, and creatine phosphate (CrP) was conducted using liquid chromatography/high-resolution mass spectrometry. We observed a significant decrease in CrP during artificial maturation of TS in SF. In contrast, ATP and ADP were not significantly affected. Addition of CCCP to SF halted maturation and led to significantly lower CrP whereas ADP significantly increased and ATP was unaffected. Dilution of matured and immature TS with AM led to a significant decrease of ATP and CrP and an increase of ADP compared with their levels before dilution, although immature TS were not motile. Energy dependency of TS maturation in sturgeon was confirmed, which suggests that mitochondrial oxidative phosphorylation is needed for maturation of sturgeon TS. PMID:26641041

  12. Effect of melatonin on maturation capacity and fertilization of Nili-Ravi buffalo (Bubalus bubalis) oocytes.

    PubMed

    Nagina, G; Asima, A; Nemat, U; Shamim, A

    2016-01-01

    This study evaluated the effect of melatonin supplementation of in vitro maturation media on in vitro maturation (IVM) and in vitro fertilization (IVF) rate of buffalo oocytes. Cumulus oocytes complexes (COCs) were aspirated from follicles of 2-8 mm diameter. In experiment I, COCs were matured in IVM medium supplemented with 0 (control), 250, 500, and 1000 μM melatonin for 22-24 hours in CO2 incubator at 38.5°C with 5% CO2 and at 95% relative humidity. The maturation rate did not differ in media supplemented with melatonin at 250 μM, 500 μM, 1000 μM and control (0 μM). In experiment II, the matured oocytes were fertilized in 50 μl droplets of Tyrode's Albumin Lactate Pyruvate (TALP) medium having 10 ug/ml heparin for sperm (2 million/ml) capacitation. The fertilization droplets were then kept for incubation at 5% CO2, 39°C and at 95% relative humidity for 18 hours. The fertilization rate was assessed by sperm penetration and pronuclear formation. Fertilization rate was improved when maturation medium was supplemented with 250 μM melatonin compared to control. In conclusion, melatonin supplementation to serum free maturation media at 250 μM improved the fertilization rate of buffalo oocytes. PMID:27540514

  13. Effect of Ca Ionophore On Blastocyst Production Following Intracytoplasmic Sperm Injection in Caprine Oocytes.

    PubMed

    Kharche, S D; Pathak, J; Agarwal, S; Kushwah, B; Sikarwar, Aks

    2016-08-01

    The aim of the present investigation was to study the effect of calcium ionophore activation on blastocyst production following intracytoplasmic sperm injection (ICSI) in in vitro-matured Caprine oocytes. A total of 470 in vitro-matured oocytes were selected and randomly divided in to three groups. Cumulus oocyte complexes (COCs) recovered by slicing the Caprine ovaries were matured in TCM199 supplemented with 10% foetal bovine serum (FBS) + 10% follicular fluid + FSH (5 μg/ml) + LH (10 μg/ml) + estradiol (1 μg/ml) + EGF (10 ng/ml) + BSA (3 mg/ml) for 27 h in humidified atmosphere at 38.5°C with 5% CO2 in CO2 incubator. After 27 h of culture, selected COCs (n = 470) were separated from cumulus cells by treating with 0.1% hyaluronidase enzyme and passing repeatedly through a fine pipette and randomly divided into three groups. In group 1, (n = 168) matured oocytes were injected with injection micropipette without sperm as control. In group 2, (n = 152) capacitated spermatozoa were injected into cytoplasm of in vitro-matured oocytes through injection micropipette. In group 3, (n = 150) capacitated spermatozoa were injected into cytoplasm of in vitro-matured oocytes through injection micropipette and then activated with 5 μm Ca ionophore for 5 min. The oocytes of all groups were then culture in RVCL media for embryo development. The cleavage rate was observed after 48-72 h of injection. The cleavage rate and blastocyst production in group 1, 2 and 3 were 0.00 and 0.00, 18.42 and 3.57 and 61.33% and 16.30%, respectively. The result indicated that mechanical activation failed to induce cleavage in in vitro-matured Caprine oocytes, whereas chemical activation of intracytoplasmic sperm-injected in vitro-matured Caprine oocytes showed significantly higher cleavage rate and blastocyst production as compare to non-activated oocytes. PMID:27170442

  14. Effect of Ca Ionophore On Blastocyst Production Following Intracytoplasmic Sperm Injection in Caprine Oocytes.

    PubMed

    Kharche, S D; Pathak, J; Agarwal, S; Kushwah, B; Sikarwar, Aks

    2016-08-01

    The aim of the present investigation was to study the effect of calcium ionophore activation on blastocyst production following intracytoplasmic sperm injection (ICSI) in in vitro-matured Caprine oocytes. A total of 470 in vitro-matured oocytes were selected and randomly divided in to three groups. Cumulus oocyte complexes (COCs) recovered by slicing the Caprine ovaries were matured in TCM199 supplemented with 10% foetal bovine serum (FBS) + 10% follicular fluid + FSH (5 μg/ml) + LH (10 μg/ml) + estradiol (1 μg/ml) + EGF (10 ng/ml) + BSA (3 mg/ml) for 27 h in humidified atmosphere at 38.5°C with 5% CO2 in CO2 incubator. After 27 h of culture, selected COCs (n = 470) were separated from cumulus cells by treating with 0.1% hyaluronidase enzyme and passing repeatedly through a fine pipette and randomly divided into three groups. In group 1, (n = 168) matured oocytes were injected with injection micropipette without sperm as control. In group 2, (n = 152) capacitated spermatozoa were injected into cytoplasm of in vitro-matured oocytes through injection micropipette. In group 3, (n = 150) capacitated spermatozoa were injected into cytoplasm of in vitro-matured oocytes through injection micropipette and then activated with 5 μm Ca ionophore for 5 min. The oocytes of all groups were then culture in RVCL media for embryo development. The cleavage rate was observed after 48-72 h of injection. The cleavage rate and blastocyst production in group 1, 2 and 3 were 0.00 and 0.00, 18.42 and 3.57 and 61.33% and 16.30%, respectively. The result indicated that mechanical activation failed to induce cleavage in in vitro-matured Caprine oocytes, whereas chemical activation of intracytoplasmic sperm-injected in vitro-matured Caprine oocytes showed significantly higher cleavage rate and blastocyst production as compare to non-activated oocytes.

  15. Observation of sperm-head vacuoles and sperm morphology under light microscope

    PubMed Central

    Park, Sol; Ko, Duck Sung; Park, Dong Wook; Yang, Kwang Moon

    2014-01-01

    Objective The presence of sperm-head vacuoles has been suspected to be deleterious to the outcomes of assisted reproductive technology (ART). It is difficult to accurately distinguish morphologically abnormal sperm with vacuoles under a light microscope. This study was performed to analyze the result of the observation of sperm-head vacuoles using Papanicolaou staining under a light microscope and whether the male partner's age affects these vacuoles. Methods Sperm morphology with vacuoles was evaluated using Papanicolaou staining and observed under a light microscope (400×) in 980 men. The normal morphology was divided into three categories (group A, <4% of normal morphology; group B, 4%-14% of normal morphology; and group C, >14% of normal morphology). The criteria for the sperm-head vacuoles were those given in the World Health Organization manual. For the analysis of the age factor, the participants were divided into the following groups: 26-30 years, 31-35 years, 36-40 years, 41-45 years, and 46-50 years. Results The percentage of sperm-head vacuoles increased with normal sperm morphology (group A vs. groups B, C) (p<0.05). In the case of the age factor, a statistically significant difference was not observed across any of the age groups. Conclusion A majority of the sperm-head vacuoles showed a statistically significant difference among normal morphology groups. Therefore, we should consider the probability of the percentage of sperm-head vacuoles not increasing with age but with abnormal sperm morphology. A further study is required to clarify the effect of the sperm-head vacuoles on ART outcomes. PMID:25309858

  16. Profiling of sperm proteins and association of sperm PDC-109 with bull fertility.

    PubMed

    Somashekar, Lakshminarayana; Selvaraju, Sellappan; Parthipan, Sivashanmugam; Ravindra, Janivara Parameswaraiah

    2015-01-01

    The composition of sperm proteins influences the fertilizing ability of sperm and hence the present study was conducted (i) to profile sperm proteins expression patterns in bulls of differing fertility index and (ii) to identify and relate the abundant sperm proteins with bull fertility. The semen samples were collected from Holstein-Friesian bulls (n = 12) varying in conception rate (CR) (high/low). The frozen semen straws (three ejaculates, from each bull) were used to study (a) sperm kinetic parameters, (b) plasmalemma integrity, (c) mitochondrial membrane potential, and (d) chromatin distribution. Three bulls were randomly selected from each group (n = 3) and the neat sperm pellets were subjected to percoll purification, followed by protein isolation using 0.1% Triton X100. The sperm kinetic parameters, plasmalemma integrity, mitochondrial membrane potential, and the chromatin distribution did not differ significantly between groups. The number of acidic (pI; 3.1-5.6, 37%) and basic (pI; 7.9-10.0, 27%) proteins and their pattern of expression varied significantly (p < 0.05) between high and low fertile bulls. The abundant sperm protein spots in 2D-gel electrophoresis (2DE) were identified as seminal plasma protein PDC-109 (i.e., protein with N-terminus aspartic acid, D and carboxy terminus cystine, having 109 amino acids) and its isoform and spermadhesin-1 (SPADH1). The western blot analysis confirmed the presence of PDC-109 isoform proteins at 15.4 kDa (pI 5.3 and 5.5). The seminal plasma protein PDC-109 was abundant in the low fertile when compared to the high fertile group (p < 0.05). This study suggests that the imbalance in acidic and basic sperm proteins may influence sperm fertility and sperm PDC-109 levels above a certain threshold affects bull fertility.

  17. Sperm motility of externally fertilizing fish and amphibians.

    PubMed

    Browne, R K; Kaurova, S A; Uteshev, V K; Shishova, N V; McGinnity, D; Figiel, C R; Mansour, N; Agney, D; Wu, M; Gakhova, E N; Dzyuba, B; Cosson, J

    2015-01-01

    We review the phylogeny, sperm competition, morphology, physiology, and fertilization environments of the sperm of externally fertilizing fish and amphibians. Increased sperm competition in both fish and anurans generally increases sperm numbers, sperm length, and energy reserves. The difference between the internal osmolarity and iconicity of sperm cells and those of the aquatic medium control the activation, longevity, and velocity of sperm motility. Hypo-osmolarity of the aquatic medium activates the motility of freshwater fish and amphibian sperm and hyperosmolarity activates the motility of marine fish sperm. The average longevity of the motility of marine fish sperm (~550 seconds) was significantly (P < 0.05) greater than that of freshwater fish sperm (~150 seconds), with the longevities of both marine and freshwater fish being significantly (P < 0.05) lower than that of anuran sperm (~4100 seconds). The average velocity of anuran sperm (25 μm/s) was significantly (P < 0.05) lower than that of marine fish (140 μm/s) or freshwater fish (135 μm/s) sperm. The longevity of the sperm of giant salamanders (Cryptobranchoidea) of approximately 600 seconds was greater than that of freshwater fish sperm but much lower than anuran sperm. Our research and information from the literature showed that higher osmolarities promote greater longevity in anuran sperm, and some freshwater fish sperm, and that anuran and cryptobranchid sperm maintained membrane integrity long after the cessation of motility, demonstrating a preferential sharing of energy reserves toward the maintenance of membrane integrity. The maintenance of the membrane integrity of anuran sperm in fresh water for up to 6 hours showed an extremely high osmotic tolerance relative to fish sperm. The very high longevity and osmotic tolerance of anuran sperm and high longevity of cryptobranchid sperm, relative to those of freshwater fish, may reflect the complex fertilization history of amphibian sperm in

  18. Sperm specific proteins-potential candidate molecules for fertility control.

    PubMed

    Suri, Anil

    2004-03-10

    The increase in population growth rate warrants the development of additional contraceptive methods that are widely acceptable, free from side effects and less expensive. Immunocontraception, and in particular the targeting of antibodies to gamete-specific antigens implicated in sperm egg binding and fertilization, offers an attractive approach to control fertility. The development of a contraceptive vaccine based on sperm antigen represents a promising approach to contraception. In mammals, fertilization is completed by the direct interaction of sperm and egg, a process mediated primarily by sperm surface proteins. Sperm have proteins that are unique, cell specific, immunogenic and accessible to antibodies. A few of the sperm specific proteins have been isolated and characterized. The antibodies raised against the sperm specific antigens have proved to be extremely effective at reducing sperm-egg interaction in vitro; fertility trials in sub-human primates would eventually prove the effectiveness of the sperm antigens in terms of contraceptive efficacy.

  19. Sperm specific proteins-potential candidate molecules for fertility control

    PubMed Central

    Suri, Anil

    2004-01-01

    The increase in population growth rate warrants the development of additional contraceptive methods that are widely acceptable, free from side effects and less expensive. Immunocontraception, and in particular the targeting of antibodies to gamete-specific antigens implicated in sperm egg binding and fertilization, offers an attractive approach to control fertility. The development of a contraceptive vaccine based on sperm antigen represents a promising approach to contraception. In mammals, fertilization is completed by the direct interaction of sperm and egg, a process mediated primarily by sperm surface proteins. Sperm have proteins that are unique, cell specific, immunogenic and accessible to antibodies. A few of the sperm specific proteins have been isolated and characterized. The antibodies raised against the sperm specific antigens have proved to be extremely effective at reducing sperm-egg interaction in vitro; fertility trials in sub-human primates would eventually prove the effectiveness of the sperm antigens in terms of contraceptive efficacy. PMID:15012833

  20. Data Product Maturity

    Atmospheric Science Data Center

    2013-03-25

    ... document, maturity levels are provided separately for each scientific data set (SDS) included with the data files. The data product ... indiscriminate use of these data products as the basis for research findings, journal publications, and/or presentations.   ...

  1. Influence of female age, sperm senescence and multiple mating on sperm viability in female Drosophila melanogaster.

    PubMed

    Radhakrishnan, Preethi; Fedorka, Kenneth M

    2011-06-01

    Sperm viability has been associated with the degree of promiscuity across species, as well as the degree of reproductive success within species. Thus, sperm survival within the female reproductive tract likely plays a key role in how mating systems evolve. In the fruit fly, Drosophila melanogaster, however, the extent and cause of sperm death has been the subject of recent debate. Here, we assess sperm death within the female reproductive tract of D. melanogaster following single and multiple matings in order to elucidate the extent of death and its potential mechanisms, including an acute female response to mating, female age and/or sperm senescence. We found no evidence that sperm viability was influenced by an acute female response or female age. We also found that rival ejaculates did not influence viability, supporting recent work in the system. Instead, the majority of death appears to be due to the aging of male gametes within the female, and that at least some dead resident sperm remain in the female after multiple mating. In contrast to earlier in vivo work, we found that overall sperm death was minimal (8.7%), indicating viability should have a negligible influence on female remating rates.

  2. Human sperm chromosome analysis after subzonal sperm insemination of hamster oocytes

    SciTech Connect

    Cozzi, J.

    1994-09-01

    Sperm microinjection techniques, subzonal sperm insemination (SUZI) and intracytoplasmic sperm injection (ICSI), have achieved a wide spread clinical application for the treatment of male infertility. To date, only one study has focused on sperm karyotypes after microinjection. Martin et al. reported a very high incidence of abnormal human sperm complements after ICSI into hamster oocytes. In the present study, are reported the first human sperm karyotypes after SUZI of hamster oocytes. Spermatozoa from two control donors were treated by calcium ionophore A23187 and injected under the zona of hamster eggs. The microinjected eggs were then cultured for cytogenetic analysis of the pronuclei. Out of 47 analyzed sperm chromosome metaphases, 5 (10.6%) were abnormal, 4 (8.5%) were hypohaploid and 1 (2.1%) had a structural abnormality. The sex ratio was not significantly different from the expected 1:1 ratio. Rates of chromosomal abnormalities in microinjected spermatozoa were similar to those observed in spermatozoa inseminated with zona free eggs, suggesting that SUZI procedure per se does not increase sperm chromosomal abnormalities.

  3. MONTHLY VARIATION IN SPERM MOTILITY IN COMMON CARP ASSESSED USING COMPUTER-ASSISTED SPERM ANALYSIS (CASA)

    EPA Science Inventory

    Sperm motility variables from the milt of the common carp Cyprinus carpio were assessed using a computer-assisted sperm analysis (CASA) system across several months (March-August 1992) known to encompass the natural spawning period. Two-year-old pond-raised males obtained each mo...

  4. Importance of papanicolaou staining for sperm morphologic analysis: comparison with an automated sperm quality analyzer.

    PubMed

    Singh, Smita; Sharma, Sunita; Jain, Manjula; Chauhan, Richa

    2011-08-01

    Without experience or proper training, the evaluation of the morphologic features of sperm can become the most confusing and time-consuming area of semen analysis. This study defined the role of Papanicolaou staining compared with an automated sperm analyzer in the management of infertility. We compared the morphologic features of sperm using Papanicolaou staining and an automated Sperm Quality Analyzer IIC-P (SQA-IIC-P; Medical Electronic Systems, Caesarea, Israel) and evaluated the role of factors affecting these features in semen samples from 201 infertile men. The sensitivity of the SQA-IIC-P was 85.5%, and the specificity was 87.3% compared with Papanicolaou staining. Although the positive predictive value of this instrument was 93.7%, the negative predictive value was only 73.3%. Moreover, sperm indices that are important for in vitro fertilization could be derived only by using the manual method. A strong correlation was seen with smoking and leukocytospermia (P < .001). The SQA-IIC-P can be used as a screening tool to evaluate the morphologic features of sperm. However, Papanicolaou staining to study the cytomorphologic features of sperm and the calculation of sperm indices should be done for quantification of defects.

  5. Ocean acidification impacts on sperm mitochondrial membrane potential bring sperm swimming behaviour near its tipping point.

    PubMed

    Schlegel, Peter; Binet, Monique T; Havenhand, Jonathan N; Doyle, Christopher J; Williamson, Jane E

    2015-04-01

    Broadcast spawning marine invertebrates are susceptible to environmental stressors such as climate change, as their reproduction depends on the successful meeting and fertilization of gametes in the water column. Under near-future scenarios of ocean acidification, the swimming behaviour of marine invertebrate sperm is altered. We tested whether this was due to changes in sperm mitochondrial activity by investigating the effects of ocean acidification on sperm metabolism and swimming behaviour in the sea urchin Centrostephanus rodgersii. We used a fluorescent molecular probe (JC-1) and flow cytometry to visualize mitochondrial activity (measured as change in mitochondrial membrane potential, MMP). Sperm MMP was significantly reduced in ΔpH -0.3 (35% reduction) and ΔpH -0.5 (48% reduction) treatments, whereas sperm swimming behaviour was less sensitive with only slight changes (up to 11% decrease) observed overall. There was significant inter-individual variability in responses of sperm swimming behaviour and MMP to acidified seawater. We suggest it is likely that sperm exposed to these changes in pH are close to their tipping point in terms of physiological tolerance to acidity. Importantly, substantial inter-individual variation in responses of sperm swimming to ocean acidification may increase the scope for selection of resilient phenotypes, which, if heritable, could provide a basis for adaptation to future ocean acidification.

  6. SMART USE OF COMPUTER-AIDED SPERM ANALYSIS (CASA) TO CHARACTERIZE SPERM MOTION

    EPA Science Inventory

    Computer-aided sperm analysis (CASA) has evolved over the past fifteen years to provide an objective, practical means of measuring and characterizing the velocity and parttern of sperm motion. CASA instruments use video frame-grabber boards to capture multiple images of spermato...

  7. Sperm cryopreservation in fish and shellfish.

    PubMed

    Tiersch, Terrence R; Yang, Huiping; Jenkins, Jill A; Dong, Qiaoxiang

    2007-01-01

    Initial success in sperm cryopreservation came at about the same time for aquatic species and livestock. However, in the 50-plus years since then cryopreserved sperm of livestock has grown into a billion-dollar global industry, while despite work in some 200 species with well over 200 published reports, cryopreservation of aquatic species sperm remains essentially a research activity with little commercial application. Most research has focused on large-bodied culture and sport fishes, such as salmonids, carps, and catfishes, and mollusks such as commercially important oyster and abalone species. However, only a handful of studies have addressed sperm cryopreservation in small fishes, such as zebrafish, and in endangered species. Overall, this work has yielded techniques that are being applied with varying levels of success around the world. Barriers to expanded application include a diverse and widely distributed literature base, technical problems, small sperm volumes, variable results, a general lack of access to the technology, and most importantly, the lack of standardization in practices and reporting. The benefits of cryopreservation include at least five levels of improvements for existing industries and for creation of new industries. First, cryopreservation can be used to improve existing hatchery operations by providing sperm on demand and simplifying the timing of induced spawning. Second, frozen sperm can enhance efficient use of facilities and create new opportunities in the hatchery by eliminating the need to maintain live males, potentially freeing resources for use with females and larvae. Third, valuable genetic lineages such as endangered species, research models, or improved farmed strains can be protected by storage of frozen sperm. Fourth, cryopreservation opens the door for rapid genetic improvement. Frozen sperm can be used in breeding programs to create improved lines and shape the genetic resources available for aquaculture. Finally

  8. Sperm-attractant peptide influences the spermatozoa swimming behavior in internal fertilization in Octopus vulgaris.

    PubMed

    De Lisa, Emilia; Salzano, Anna Maria; Moccia, Francesco; Scaloni, Andrea; Di Cosmo, Anna

    2013-06-15

    Marine invertebrates exhibit both chemokinesis and chemotaxis phenomena, induced in most cases by the release of water-borne peptides or pheromones. In mollusks, several peptides released during egg-laying improve both male attraction and mating. Unlike other cephalopods, Octopus vulgaris adopts an indirect internal fertilization strategy. We here report on the identification and characterization of a chemoattractant peptide isolated from mature eggs of octopus females. Using two-chamber and time-lapse microscopy assays, we demonstrate that this bioactive peptide is able to increase sperm motility and induce chemotaxis by changing the octopus spermatozoa swimming behavior in a dose-dependent manner. We also provide evidence that chemotaxis in the octopus requires the presence of extracellular calcium and membrane protein phophorylation at tyrosine. This study is the first report on a sperm-activating factor in a non-free-spawning marine animal.

  9. Epididymal Hypo-Osmolality Induces Abnormal Sperm Morphology and Function in the Estrogen Receptor Alpha Knockout Mouse1

    PubMed Central

    Joseph, Avenel; Shur, Barry D.; Ko, CheMyong; Chambon, Pierre; Hess, Rex A.

    2010-01-01

    Estrogen receptor-alpha (ESR1) is highly expressed in the efferent ductules of all species studied as well as in the epididymal epithelium in mice and other select species. Male mice lacking ESR1 (Esr1KO) are infertile, but transplantation studies demonstrated that Esr1KO germ cells are capable of fertilization when placed in a wild-type reproductive tract. These results suggest that extratesticular regions, such as the efferent ductules and epididymis, are the major source of pathological changes in Esr1KO males. Previous studies have shown alterations in ion and fluid transporters in the efferent duct and epididymal epithelia of Esr1KO males, leading to misregulation of luminal fluid pH. To determine the effect of an altered epididymal milieu on Esr1KO sperm, we assayed sperm morphology in the different regions of the epididymis. Sperm recovered from the epididymis exhibited abnormal flagellar coiling and increased incidence of spontaneous acrosome reactions, both of which are consistent with exposure to abnormal epididymal fluid. Analysis of the epididymal fluid revealed that the osmolality of the Esr1KO fluid was reduced relative to wild type, consistent with prior reports of inappropriate fluid absorption from the efferent ductules. This, along with the finding that morphological defects increased with transit through the epididymal duct, suggests that the anomalies in sperm are a consequence of the abnormal luminal environment. Consistent with this, incubating Esr1KO sperm in a more wild-type-like osmotic environment significantly rescued the abnormal flagellar coiling. This work demonstrates that Esr1KO mice exhibit an abnormal fluid environment in the lumen of the efferent ducts and epididymis, precluding normal sperm maturation and instead resulting in progressive deterioration of sperm that contributes to infertility. PMID:20130266

  10. Exposure to 17α-ethinylestradiol decreases motility and ATP in sperm of male fighting fish Betta splendens.

    PubMed

    Montgomery, Tracy M; Brown, Alexandria C; Gendelman, Hannah K; Ota, Mizuho; Clotfelter, Ethan D

    2014-03-01

    The synthetic estrogen 17α-ethinylestradiol (EE2) is an endocrine-disrupting chemical released into aquatic environments from sewage treatment facilities. We tested the effects of two environmentally relevant concentrations of waterborne EE2, 10 and 100 ng L(-1) , on reproductive endpoints in the teleost fish Betta splendens. In the first experiment, testes were removed from males and sperm were exposed to EE2 directly through the activation water. Direct exposure to EE2 had no effect on any measure of sperm swimming performance. In the second experiment, we exposed sexually mature male B. splendens to EE2 using a semi-static exposure protocol for 4 weeks. There were no significant treatment effects in the 10 ng L(-1) treatment group, but at the 100 ng L(-1) dose we found that fish had smaller gonads and reduced sperm swimming velocity. When allowed to interact freely with female conspecifics, males exposed to 100 ng L(-1) EE2 built smaller nests and showed a nonsignificant decrease in fertilization success. To investigate further the potential mechanism underlying the decrease in sperm quality, we repeated the chronic exposure experiment and analyzed the ATP content of sperm from fish in each treatment group. We found that males exposed to 100 ng L(-1) of EE2 had fewer moles of ATP per sperm than did fish in the other two treatment groups, suggesting that a decrease in intracellular ATP caused a reduction in sperm swimming velocity. The current study adds to the growing body of literature that indicates the risks to aquatic organisms of exposure to environmentally relevant concentrations of EE2.

  11. Spermiogenesis in Psilochorus simoni (Berland, 1911) (Pholcidae, Araneae): evidence for considerable within-family variation in sperm structure and development.

    PubMed

    Michalik, Peter; Huber, Bernhard A

    2006-01-01

    A large number of characters and considerable variation among taxa make animal sperm cells promising objects for phylogenetic studies. However, our knowledge about sperm structure and development in spiders is still rudimentary. In pholcids, previous studies of two species representing different subfamily level taxa have revealed conspicuous differences. Here, we report on a representative of a third subfamily level taxon, confirming substantial variation in sperm structure and development within the family. The male genital system in Psilochorus simoni (Berland, 1911) consists of paired testes and deferent ducts which lead into a common ejaculatory duct. The somatic cells of the testes show a high secretory activity, and produce at least two different kinds of secretion. The spermatozoa show features already known from other Pholcidae as well as unique characters. The acrosomal vacuole is tube-like with a narrow subacrosomal space. The axoneme migrates deep into the nucleus and is finally located near the acrosomal vacuole. Thus, the postcentriolar elongation of the nucleus is very long. A centriolar adjunct is not present and after the coiling process the implantation fossa is completely filled with glycogen which is also found in larger amounts within the cytoplasm of the sperm cell. After the coiling process, a vesicular area is present that becomes most prominent in the periphery of the sperm cell and surrounds the axoneme and parts of the nucleus. The secretion sheath surrounding the mature spermatozoon is already formed in the lumen of the testis, possibly by a secretion present in the testis but absent in the deferent duct. Sperm are transferred as cleistospermia. Results are compared with previous studies on pholcid spermiogenesis and sperm structure.

  12. Group X phospholipase A2 is released during sperm acrosome reaction and controls fertility outcome in mice

    PubMed Central

    Escoffier, Jessica; Jemel, Ikram; Tanemoto, Akemi; Taketomi, Yoshitaka; Payre, Christine; Coatrieux, Christelle; Sato, Hiroyasu; Yamamoto, Kei; Masuda, Seiko; Pernet-Gallay, Karin; Pierre, Virginie; Hara, Shuntaro; Murakami, Makoto; De Waard, Michel; Lambeau, Gérard; Arnoult, Christophe

    2010-01-01

    Ejaculated mammalian sperm must undergo a maturation process called capacitation before they are able to fertilize an egg. Several studies have suggested a role for members of the secreted phospholipase A2 (sPLA2) family in capacitation, acrosome reaction (AR), and fertilization, but the molecular nature of these enzymes and their specific roles have remained elusive. Here, we have demonstrated that mouse group X sPLA2 (mGX) is the major enzyme present in the acrosome of spermatozoa and that it is released in an active form during capacitation through spontaneous AR. mGX-deficient male mice produced smaller litters than wild-type male siblings when crossed with mGX-deficient females. Further analysis revealed that spermatozoa from mGX-deficient mice exhibited lower rates of spontaneous AR and that this was associated with decreased in vitro fertilization (IVF) efficiency due to a drop in the fertilization potential of the sperm and an increased rate of aborted embryos. Treatment of sperm with sPLA2 inhibitors and antibodies specific for mGX blocked spontaneous AR of wild-type sperm and reduced IVF success. Addition of lysophosphatidylcholine, a catalytic product of mGX, overcame these deficiencies. Finally, recombinant mGX triggered AR and improved IVF outcome. Taken together, our results highlight a paracrine role for mGX during capacitation in which the enzyme primes sperm for efficient fertilization and boosts premature AR of a likely phospholipid-damaged sperm subpopulation to eliminate suboptimal sperm from the pool available for fertilization. PMID:20424324

  13. An alkaline follicular fluid fraction induces capacitation and limited release of oviduct epithelium-bound stallion sperm.

    PubMed

    Leemans, Bart; Gadella, Bart M; Stout, Tom A E; Nelis, Hilde; Hoogewijs, Maarten; Van Soom, Ann

    2015-09-01

    Induction of hyperactivated motility is considered essential for triggering the release of oviduct-bound mammalian spermatozoa in preparation for fertilization. In this study, oviduct-bound stallion spermatozoa were exposed for 2 h to: i) pre-ovulatory and ii) post-ovulatory oviductal fluid; iii) 100% and iv) 10% follicular fluid (FF); v) cumulus cells, vi) mature equine oocytes, vii) capacitating and viii) non-capacitating medium. None of these triggered sperm release or hyperactivated motility. Interestingly, native FF was detrimental to sperm viability, an effect that was negated by heat inactivation, charcoal treatment and 30 kDa filtration alone or in combination. Moreover, sperm suspensions exposed to treated FF at pH 7.9 but not pH 7.4 showed Ca(2+)-dependent hypermotility. Fluo-4 AM staining of sperm showed elevated cytoplasmic Ca(2+) in hyperactivated stallion spermatozoa exposed to treated FF at pH 7.9 compared to a modest response in defined capacitating conditions at pH 7.9 and no response in treated FF at pH 7.4. Moreover, 1 h incubation in alkaline, treated FF induced protein tyrosine phosphorylation in 20% of spermatozoa. None of the conditions tested induced widespread release of sperm pre-bound to oviduct epithelium. However, the hyperactivating conditions did induce release of 70-120 spermatozoa per oviduct explant, of which 48% showed protein tyrosine phosphorylation and all were acrosome-intact, but capable of acrosomal exocytosis in response to calcium ionophore. We conclude that, in the presence of elevated pH and extracellular Ca(2+), a heat-resistant, hydrophilic, <30 kDa component of FF can trigger protein tyrosine phosphorylation, elevated cytoplasmic Ca(2+) and hyperactivated motility in stallion sperm, but infrequent release of sperm pre-bound to oviduct epithelium.

  14. Exposure to 17α-ethinylestradiol decreases motility and ATP in sperm of male fighting fish Betta splendens.

    PubMed

    Montgomery, Tracy M; Brown, Alexandria C; Gendelman, Hannah K; Ota, Mizuho; Clotfelter, Ethan D

    2014-03-01

    The synthetic estrogen 17α-ethinylestradiol (EE2) is an endocrine-disrupting chemical released into aquatic environments from sewage treatment facilities. We tested the effects of two environmentally relevant concentrations of waterborne EE2, 10 and 100 ng L(-1) , on reproductive endpoints in the teleost fish Betta splendens. In the first experiment, testes were removed from males and sperm were exposed to EE2 directly through the activation water. Direct exposure to EE2 had no effect on any measure of sperm swimming performance. In the second experiment, we exposed sexually mature male B. splendens to EE2 using a semi-static exposure protocol for 4 weeks. There were no significant treatment effects in the 10 ng L(-1) treatment group, but at the 100 ng L(-1) dose we found that fish had smaller gonads and reduced sperm swimming velocity. When allowed to interact freely with female conspecifics, males exposed to 100 ng L(-1) EE2 built smaller nests and showed a nonsignificant decrease in fertilization success. To investigate further the potential mechanism underlying the decrease in sperm quality, we repeated the chronic exposure experiment and analyzed the ATP content of sperm from fish in each treatment group. We found that males exposed to 100 ng L(-1) of EE2 had fewer moles of ATP per sperm than did fish in the other two treatment groups, suggesting that a decrease in intracellular ATP caused a reduction in sperm swimming velocity. The current study adds to the growing body of literature that indicates the risks to aquatic organisms of exposure to environmentally relevant concentrations of EE2. PMID:22223459

  15. EXCEPTIONS TO THE PREVAILING PATTERN OF TUBULES (9 + 9 + 2) IN THE SPERM FLAGELLA OF CERTAIN INSECT SPECIES

    PubMed Central

    Phillips, David M.

    1969-01-01

    Various deviations from classical 9 + 2 flagellar structure are found in sperm of insect species. In mature spermatozoa of a psocid, Psocus, the outer flagellar tubules are not straight, but are disposed in a long-pitched helix such that they form an angle of about 8° with a single dense rod located in the position usually occupied by the central pair. In young spermatids of Psocus the outer tubules are straight; thus, spiraling of the flagellar tubules occurs during the course of spermiogenesis. Spiraling of flagella also occurs in the cat flea Ctenocephalides felis. Variations in the number and morphology of the central element or elements occur in other insect species besides Psocus. Among the observed deviations from a central pair of tubules are a 9 + 0 tubule pattern in the sperm of three species of mayflies, a 9 + 1 tubule pattern in the sperm of two species of mosquitoes, and 9 + 7 tubules in sperm of two species of caddis flies. Spermatozoa of treehoppers vary in yet another respect from the typical 9 + 9 + 2 insect flagellum. These sperm tails branch into four long tails, three of which each contain two doublet and two singlet tubules while the fourth branch contains three doublet and three singlet tubules. The wide distribution of insects with aberrant flagella suggests that the variant forms have evolved independently. PMID:5812428

  16. Inhibition of viral reverse transcriptase and human sperm DNA polymerase by anti-sperm antibodies.

    PubMed Central

    Witkin, S S; Higgins, P J; Bendich, A

    1978-01-01

    The IgG fraction of serum from a rabbit immunized with detergent-prepared human sperm nuclei inhibited the DNA polymerase activities in human sperm and seminal fluid as well as the partially purified reverse transcriptase of the baboon endogenous type-C retrovirus (BEV). The analogous enzymes from lysates of oncogenic type-C viruses was unaffected. IgG from the serum of individual partners from infertile marriages similarly inhibited both purified BEV reverse transcriptase and human sperm DNA polymerase, but not a DNA polymerase isolated from human prostatic fluid. The data suggest that BEV reverse transcriptase and the human sperm DNA polymerase are antigenically related. Furthermore, the sperm appears to be auto-antigenic and the antibodies thus formed may be capable of interfering with reproductive success. PMID:82498

  17. Sperm-egg interaction and functional assessment of springbok, impala and blesbok cauda epididymal spermatozoa using a domestic cattle in vitro fertilization system.

    PubMed

    Chatiza, F P; Bartels, P; Nedambale, T L; Wagenaar, G M

    2013-12-01

    The study assesses the possibility to estimate the potential fertility of post-thawed antelope (Antidorcas marsupialis), impala (Aepyceros melampus) and blesbok (Damaliscus dorcus phillipsi) epididymal sperm using homologous and heterologous IVF and the functioning of cattle IVF system to produce antelope embryos. Cauda epididymal sperm were collected from the antelope and cryopreserved under field conditions. In vitro matured domestic cow, blesbok and springbok oocytes were co-incubated in modified-Tyrode Lactate (m-TL) IVF media with springbok, impala and blesbok sperm for heterologous IVF and springbok and blesbok sperm for homologous IVF. A group of presumptive zygotes from each treatment were examined for sperm penetration and male pronuclear formation after 18h and the remainder were cultured and evaluated for embryo cleavage 22h later. The study shows that Modified Tyrode Lactate in vitro fertilization media supports survivability, capacitation and hyperactivation of springbok, impala and blesbok sperm. Springbok, impala and blesbok post-thawed epididymal spermatozoa are capable of fertilizing domestic cow oocytes under conditions that support domestic cattle IVF. Penetration, male pronuclear formation and embryo cleavage did not differ (p>0.05) between cow oocytes inseminated with sperm from springbok, impala or blesbok however these parameters were higher (p<0.05) for oocytes inseminated with bull sperm. Modified Tyrode Lactate IVF media supported homologous fertilization and embryo development in springbok and blesbok however did not support blastocyst development. These findings suggest that cattle provide a useful model for evaluating springbok, impala and blesbok post-thawed cauda epididymal sperm functionality. Domestic cattle embryo culture conditions need to be modified to promote blastosyst development in these antelope species. Such research provides an important tool in assisted reproductive technology development when high biological value

  18. The Influence of Chromosome Content on the Size and Shape of Sperm Heads in DROSOPHILA MELANOGASTER and the Demonstration of Chromosome Loss during Spermiogenesis

    PubMed Central

    Hardy, Robert Walter

    1975-01-01

    The volumes of sperm heads were estimated from three-dimensional reconstructions of serially sectioned bundles of nearly mature spermatid nuclei. Cysts from males in which all sperm are expected to have comparable amounts of chromatin (X/Y and In(3LR)/+) show unimodal frequency distributions of nuclear volumes, whereas cysts from males in which meiotic segregation is expected to deliver unequal amounts of chromatin material to spermatid nuclei show two (XY/O and XY/Y) or more (T(2;3)/+ and C(2L);C(2R)) modes. The mean volumes of the subpopulations in these cases are related in the same proportions as the metaphase lengths of their chromosomal complements. Thus the volumes of sperm nuclei are proportional to their DNA content. Sperm head shape, on the other hand, does not appear to be very sensitive to chromosomal constitution, as heads of different size do not vary greatly in shape.—The numbers of sperm heads in the various size classes in a cyst depart from mendelian expectations; these departures are caused by the elimination, during individualization, of chromosomes contained within micronuclei that are formed in spermatids at the end of the second meiotic division. The effect of this chromosome loss is to increase the proportion of nullosomic gametes in the sperm pool.—The relative frequencies of XY-bearing and nullo-X, nullo-Y sperm in XY/O males were estimated from the volume measurements. Taking this estimate as a measure of the fertilizing population, it is possible to infer from the change in sex ratio over time following insemination, that XY-bearing sperm have an advantage of 1.5 over nullo-X, nullo-Y sperm in leaving the seminal receptacle of the female for fertilization of ova. PMID:805747

  19. Sperm-egg interaction and functional assessment of springbok, impala and blesbok cauda epididymal spermatozoa using a domestic cattle in vitro fertilization system.

    PubMed

    Chatiza, F P; Bartels, P; Nedambale, T L; Wagenaar, G M

    2013-12-01

    The study assesses the possibility to estimate the potential fertility of post-thawed antelope (Antidorcas marsupialis), impala (Aepyceros melampus) and blesbok (Damaliscus dorcus phillipsi) epididymal sperm using homologous and heterologous IVF and the functioning of cattle IVF system to produce antelope embryos. Cauda epididymal sperm were collected from the antelope and cryopreserved under field conditions. In vitro matured domestic cow, blesbok and springbok oocytes were co-incubated in modified-Tyrode Lactate (m-TL) IVF media with springbok, impala and blesbok sperm for heterologous IVF and springbok and blesbok sperm for homologous IVF. A group of presumptive zygotes from each treatment were examined for sperm penetration and male pronuclear formation after 18h and the remainder were cultured and evaluated for embryo cleavage 22h later. The study shows that Modified Tyrode Lactate in vitro fertilization media supports survivability, capacitation and hyperactivation of springbok, impala and blesbok sperm. Springbok, impala and blesbok post-thawed epididymal spermatozoa are capable of fertilizing domestic cow oocytes under conditions that support domestic cattle IVF. Penetration, male pronuclear formation and embryo cleavage did not differ (p>0.05) between cow oocytes inseminated with sperm from springbok, impala or blesbok however these parameters were higher (p<0.05) for oocytes inseminated with bull sperm. Modified Tyrode Lactate IVF media supported homologous fertilization and embryo development in springbok and blesbok however did not support blastocyst development. These findings suggest that cattle provide a useful model for evaluating springbok, impala and blesbok post-thawed cauda epididymal sperm functionality. Domestic cattle embryo culture conditions need to be modified to promote blastosyst development in these antelope species. Such research provides an important tool in assisted reproductive technology development when high biological value

  20. Towards microfluidic sperm refinement: impedance-based analysis and sorting of sperm cells.

    PubMed

    de Wagenaar, B; Dekker, S; de Boer, H L; Bomer, J G; Olthuis, W; van den Berg, A; Segerink, L I

    2016-04-21

    The use of high quality semen for artificial insemination in the livestock industry is essential for successful outcome. Insemination using semen with a high number of sperm cells containing morphological defects has a negative impact on fertilization outcome. Therefore, semen with a high number of these abnormal cells is discarded in order to maintain high fertilization potential, resulting in the loss of a large number of morphologically normal sperm cells (up to 70-80% of original sample). A commonly occurring morphological sperm anomaly is the cytoplasmic droplet on the sperm flagella. Currently, no techniques are available to extract morphologically normal sperm cells from rejected samples. Therefore, we aim to develop a microfluidic setup which is able to detect and sort morphologically normal sperm cells label-free and non-invasively. In a proof-of-concept experiment, differential impedance measurements were used to detect the presence of cytoplasmic droplets on sperm flagella, which was quantified by calculating the area under the curve (AUC) of the corresponding impedance peaks. A receiver operating characteristic curve of this electrical analysis method showed the good predictive power of this analysis method (AUC value of 0.85). Furthermore, we developed a label-free cell sorting system using LabVIEW, which is capable of sorting sperm cells based on impedance. In a proof-of-concept experiment, sperm cells and 3 μm beads were sorted label-free and non-invasively using impedance detection and dielectrophoresis sorting. These experiments present our first attempt to perform sperm refinement using microfluidic technology. PMID:27025866

  1. Different computer-assisted sperm analysis (CASA) systems highly influence sperm motility parameters.

    PubMed

    Boryshpolets, S; Kowalski, R K; Dietrich, G J; Dzyuba, B; Ciereszko, A

    2013-10-15

    In this study, we examined different computer-assisted sperm analysis (CASA) systems (CRISMAS, Hobson Sperm Tracker, and Image J CASA) on the exact same video recordings to evaluate the differences in sperm motility parameters related to the specific CASA used. To cover a wide range of sperm motility parameters, we chose 12-second video recordings at 25 and 50 Hz frame rates after sperm motility activation using three taxonomically distinct fish species (sterlet: Acipenser ruthenus L.; common carp: Cyprinus carpio L.; and rainbow trout: Oncorhynchus mykiss Walbaum) that are characterized by essential differences in sperm behavior during motility. Systematically higher values of velocity and beat cross frequency (BCF) were observed in video recordings obtained at 50 Hz frame frequency compared with 25 Hz for all three systems. Motility parameters were affected by the CASA and species used for analyses. Image J and CRISMAS calculated higher curvilinear velocity (VCL) values for rainbow trout and common carp at 25 Hz frequency compared with the Hobson Sperm Tracker, whereas at 50 Hz, a significant difference was observed only for rainbow trout sperm recordings. No significant difference was observed between the CASA systems for sterlet sperm motility at 25 and 50 Hz. Additional analysis of 1-second segments taken at three time points (1, 6, and 12 seconds of the recording) revealed a dramatic decrease in common carp and rainbow trout sperm speed. The motility parameters of sterlet spermatozoa did not change significantly during the 12-second motility period and should be considered as a suitable model for longer motility analyses. Our results indicated that the CASA used can affect motility results even when the same motility recordings are used. These results could be critically altered by the recording quality, time of analysis, and frame rate of camera, and could result in erroneous conclusions.

  2. Thyroxin Is Useful to Improve Sperm Motility

    PubMed Central

    Mendeluk, Gabriela Ruth; Rosales, Mónica

    2016-01-01

    Background The aim of this study was to evaluate the non-genomic action of thyroxin on sperm kinetic and its probable use to improve sperm recovery after applying an en- richment method like “swim-up” in comparison with the available one, pentoxifylline. Materials and Methods This is an experimental study. A total of 50 patients were re- cruited, followed by infertility consultation. Conventional sperm assays were performed according to World Health Organization criteria-2010 (WHO-2010). A Computer Aided Semen Analysis System was employed to assess kinetic parameters and concentrations. Number of the motile sperm recovered after preparation technique was calculated. Results Addition of T4 (0.002 µg/ml) to semen samples increased hypermotility at 20 minutes (control: 14.18 ± 5.1% vs. 17.66 ± 8.88%, P<0.03, data expressed as mean ± SD) and remained unchanged after 40 minutes. Significant differences were found in the motile sperm recovered after swim-up (control: 8.93×106 ± 9.52× 06vs. 17.20×106 ± 21.16×106, P<0.03), achieving all of the tested samples a desirable threshold value for artificial insemination outcome, while adding pentoxifylline increased the number of recovered sperm after swim-up in 60% of the studied cases. No synergism between two treatments could be determined. Conclusion We propose a new physiological tool to artificially improve insemination. The discussion opens windows to investigate unknown pathways involved in sperm ca- pacitation and gives innovative arguments to better understand infertility mechanisms. PMID:27441054

  3. Age-associated sperm DNA methylation alterations: possible implications in offspring disease susceptibility.

    PubMed

    Jenkins, Timothy G; Aston, Kenneth I; Pflueger, Christian; Cairns, Bradley R; Carrell, Douglas T

    2014-07-01

    Recent evidence demonstrates a role for paternal aging on offspring disease susceptibility. It is well established that various neuropsychiatric disorders (schizophrenia, autism, etc.), trinucleotide expansion associated diseases (myotonic dystrophy, Huntington's, etc.) and even some forms of cancer have increased incidence in the offspring of older fathers. Despite strong epidemiological evidence that these alterations are more common in offspring sired by older fathers, in most cases the mechanisms that drive these processes are unclear. However, it is commonly believed that epigenetics, and specifically DNA methylation alterations, likely play a role. In this study we have investigated the impact of aging on DNA methylation in mature human sperm. Using a methylation array approach we evaluated changes to sperm DNA methylation patterns in 17 fertile donors by comparing the sperm methylome of 2 samples collected from each individual 9-19 years apart. With this design we have identified 139 regions that are significantly and consistently hypomethylated with age and 8 regions that are significantly hypermethylated with age. A representative subset of these alterations have been confirmed in an independent cohort. A total of 117 genes are associated with these regions of methylation alterations (promoter or gene body). Intriguingly, a portion of the age-related changes in sperm DNA methylation are located at genes previously associated with schizophrenia and bipolar disorder. While our data does not establish a causative relationship, it does raise the possibility that the age-associated methylation of the candidate genes that we observe in sperm might contribute to the increased incidence of neuropsychiatric and other disorders in the offspring of older males. However, further study is required to determine whether, and to what extent, a causative relationship exists. PMID:25010591

  4. Experimental evolution of sperm competitiveness in a mammal

    PubMed Central

    2011-01-01

    Background When females mate with multiple partners, sperm from rival males compete to fertilise the ova. Studies of experimental evolution have proven the selective action of sperm competition on male reproductive traits. However, while reproductive traits may evolve in response to sperm competition, this does not necessarily provide evidence that sperm competitive ability responds to selection. Indeed, a study of Drosophila failed to observe divergence in sperm competitive ability of males in lines selected for enhanced sperm offence and defence. Results Adopting the naturally polygamous house mouse (Mus domesticus) as our vertebrate model, we performed an experimental evolution study and observed genetic divergence in sperm quality; males from the polygamous selection lines produced ejaculates with increased sperm numbers and greater sperm motility compared to males from the monogamous lines. Here, after 12 generations of experimental evolution, we conducted competitive matings between males from lineages evolving under sperm competition and males from lineages subject to relaxed selection. We reduced variation in paternity arising from embryo mortality by genotyping embryos in utero at 14 days gestation. Our microsatellite data revealed a significant paternity bias toward males that evolved under the selective regime of sperm competition. Conclusion We provide evidence that the sperm competitiveness phenotype can respond to selection, and show that improved sperm quality translates to greater competitive fertilisation success in house mice. PMID:21251249

  5. Female choice of young sperm in a genetically monogamous bird.

    PubMed Central

    Wagner, Richard H; Helfenstein, Fabrice; Danchin, Etienne

    2004-01-01

    When females copulate with multiple males the potential exists for female sperm choice. Females may increase the probability of being fertilized by preferred males by selectively retaining their sperm while ejecting the sperm of unfavoured males. An alternative criterion to male quality for female sperm choice may be sperm age because old sperm degrade and can lead to zygote death or unhealthy offspring. Here, we report that in a genetically monogamous bird, the black-legged kittiwake Rissa tridactyla, females eject their mates' sperm according to when the copulations were performed. Following copulations that were performed approximately two weeks before egg laying, females ejected inseminations at high frequencies while retaining inseminations that occurred soon before laying. Females that suffered hatching failure had ejected sperm from early copulations less than half as frequently as females whose entire clutches hatched. Furthermore, chicks that hatched from eggs fertilized by old sperm were in poor condition relative to those fertilized by young sperm. These findings support the 'young sperm' hypothesis, which predicts that females choose fresh sperm to avoid reproductive failure and are the first to show intra-male sperm choice by females. PMID:15252964

  6. DNA fragmentation and sperm head morphometry in cat epididymal spermatozoa.

    PubMed

    Vernocchi, Valentina; Morselli, Maria Giorgia; Lange Consiglio, Anna; Faustini, Massimo; Luvoni, Gaia Cecilia

    2014-10-15

    Sperm DNA fragmentation is an important parameter to assess sperm quality and can be a putative fertility predictor. Because the sperm head consists almost entirely of DNA, subtle differences in sperm head morphometry might be related to DNA status. Several techniques are available to analyze sperm DNA fragmentation, but they are labor-intensive and require expensive instrumentations. Recently, a kit (Sperm-Halomax) based on the sperm chromatin dispersion test and developed for spermatozoa of different species, but not for cat spermatozoa, became commercially available. The first aim of the present study was to verify the suitability of Sperm-Halomax assay, specifically developed for canine semen, for the evaluation of DNA fragmentation of epididymal cat spermatozoa. For this purpose, DNA fragmentation indexes (DFIs) obtained with Sperm-Halomax and terminal deoxynucleotidyl transferase-mediated nick-end labeling (TUNEL) were compared. The second aim was to investigate whether a correlation between DNA status, sperm head morphology, and morphometry assessed by computer-assisted semen analysis exists in cat epididymal spermatozoa. No differences were observed in DFIs obtained with Sperm-Halomax and TUNEL. This result indicates that Sperm-Halomax assay provides a reliable evaluation of DNA fragmentation of epididymal feline spermatozoa. The DFI seems to be independent from all the measured variables of sperm head morphology and morphometry. Thus, the evaluation of the DNA status of spermatozoa could effectively contribute to the completion of the standard analysis of fresh or frozen semen used in assisted reproductive technologies.

  7. Two Types of Assays for Detecting Frog Sperm Chemoattraction

    PubMed Central

    Burnett, Lindsey A.; Tholl, Nathan; Chandler, Douglas E.

    2011-01-01

    Sperm chemoattraction in invertebrates can be sufficiently robust that one can place a pipette containing the attractive peptide into a sperm suspension and microscopically visualize sperm accumulation around the pipette1. Sperm chemoattraction in vertebrates such as frogs, rodents and humans is more difficult to detect and requires quantitative assays. Such assays are of two major types - assays that quantitate sperm movement to a source of chemoattractant, so-called sperm accumulation assays, and assays that actually track the swimming trajectories of individual sperm. Sperm accumulation assays are relatively rapid allowing tens or hundreds of assays to be done in a single day, thereby allowing dose response curves and time courses to be carried out relatively rapidly. These types of assays have been used extensively to characterize many well established chemoattraction systems - for example, neutrophil chemotaxis to bacterial peptides and sperm chemotaxis to follicular fluid. Sperm tracking assays can be more labor intensive but offer additional data on how chemoattractancts actually alter the swimming paths that sperm take. This type of assay is needed to demonstrate the orientation of sperm movement relative to the chemoattrractant gradient axis and to visualize characteristic turns or changes in orientation that bring the sperm closer to the egg. Here we describe methods used for each of these two types of assays. The sperm accumulation assay utilized is called a "two-chamber" assay. Amphibian sperm are placed in a tissue culture plate insert with a polycarbonate filter floor having 12 μm diameter pores. Inserts with sperm are placed into tissue culture plate wells containing buffer and a chemoatttractant carefully pipetted into the bottom well where the floor meets the wall (see Fig. 1). After incubation, the top insert containing the sperm reservoir is carefully removed, and sperm in the bottom chamber that have passed through the membrane are removed

  8. The development of cat testicular sperm cryopreservation protocols: Effects of tissue fragments or sperm cell suspension.

    PubMed

    Chatdarong, Kaywalee; Thuwanut, Paweena; Morrell, Jane M

    2016-01-15

    In endangered animals that have been found dead or sterilized for medical reasons, testis is the ultimate source of haploid DNA or sperm. Thus, preservation of testicular sperm may be performed to rescue their genetics. The aim of this study was to evaluate protocols for testicular sperm freezing: as tissue fragments or cell suspension in domestic cats as a model. A pair of testes from each cat (n = 9) were cut into eight equal pieces. Four randomly selected pieces were cryopreserved as: (1) tissue pieces using two-step freezing; (2) tissue pieces using a slow passive cooling device (CoolCell); (3) sperm suspension after single-layer centrifugation (SLC) through colloids; and (4) sperm suspension without being processed through SLC. A testicular piece from each cat served as fresh control. Testicular sperm membrane and DNA integrity were evaluated before, and after, the cryopreservation process. In addition, spermatogenic cell types (testicular sperm, spermatogonia, spermatocyte, and spermatid) present in the suspension samples were counted before and after SLC. The results found that testicular sperm membrane integrity in the suspension after SLC process was higher than that in the fragment form neither using the two-step nor CoolCell freezing, both before and after freezing (before freezing: 92.3 ± 3.4 vs. 81 ± 4.5 and 80.0 ± 7.0; after freezing: 84.5 ± 4.6 vs. 71.2 ± 12 and 76.2 ± 4.6; P ≤ 0.05). Testicular sperm DNA integrity was, however, not different among groups. Furthermore, the samples processed through the SLC had higher ration of sperm cells: other spermatogenic cells than those were not processed through the SLC (88.9 ± 3.8 vs. 30 ± 7.9; P ≤ 0.05). In summary, testicular sperm cryopreserved as a minced suspension is considered suitable in terms of preventing sperm membrane integrity, and SLC is considered a selection tool for enriching haploid sperm cells from castrated or postmortem cats.

  9. The male reproductive system of Zorotypus caudelli Karny (Zoraptera): Sperm structure and spermiogenesis.

    PubMed

    Dallai, R; Mercati, D; Gottardo, M; Machida, R; Mashimo, Y; Beutel, R G

    2011-11-01

    Considering the overall uniformity of the morphology of Zoraptera, the structural diversity of the male genital system is remarkable. Structures related to the male reproductive system of Zorotypus caudelli differ profoundly from those of Zorotypus hubbardi. The testes are elongated rather than spherical, the seminal vesicle is apparently absent, and the deferent ducts are very long. A feature shared by these two species and other zorapterans examined is that the two accessory glands are closely adherent to each other and form a single large structure, from which the ejaculatory duct originates. This is a potential zorapteran autapomorphy. Another feature possibly present in the groundplan of the order is the strong elongation of the sperm cells. This may be connected with a reproductive strategy of males trying to avoid re-mating of females with other males after the first copulation. The extremely long and coiled spermathecal duct of Z. caudelli and other zorapteran species is possibly correlated with the sperm elongation, and both features combined may result in a sexual isolating mechanism. The short duration of mating of Zorotypus barberi and Zorotypus gurneyi suggests that the male introduces sperm into the female tract up to the opening of the spermathecal duct using their long coiled aedeagus. A thick glycocalyx around the sperm in the distal part of the deferent ducts probably protects the sperm cells during their forward progression towards the long spermathecal duct, and is removed when they reach the apical receptacle. The spermatogenesis of Z. caudelli follows a pattern commonly found in insects, but differs distinctly from that of Z. hubbardi in the number of spermatids in each sperm cyst. An unusual and possibly autapomorphic feature of Z. caudelli is a disconnection of sub-tubules A and B at the level of microtubule doublets 1 and 6 of the mature sperm cells. It is conceivable that this results in a shorter period of sperm motility. The

  10. Tracking sperm in three-dimensions.

    PubMed

    Corkidi, G; Taboada, B; Wood, C D; Guerrero, A; Darszon, A

    2008-08-15

    Sperm motility, crucial for fertilization, has been mostly studied in two dimensions (2D) by recording their swimming trajectories near a flat surface. However, spermatozoa swim in three-dimensions (3D) to find eggs, with their speed being the main impediment to track them under realistic conditions. Here, we describe a novel method allowing 3D tracking and analysis of the trajectories of multiple free-swimming sperm. The system uses a piezo-electric device displacing a large focal distance objective mounted on a microscope to acquire 70 image stacks per second, each stack composed of 60 images that span a depth of 100 microm. With this method, 3D paths of multiple sperm in the same field could be visualized simultaneously during 1 s. Within the same sample we found that surface-confined sperm swam 25% slower, produced 3-fold fewer circular revolutions per second, and had trajectories of 134% greater radius of curvature than those sperm swimming freely in 3D. PMID:18555013

  11. Sperm Cells of a Primitive Strepsipteran.

    PubMed

    Nardi, James B; Delgado, Juan A; Collantes, Francisco; Miller, Lou Ann; Bee, Charles M; Kathirithamby, Jeyaraney

    2013-09-04

    The unusual life style of Strepsiptera has presented a long-standing puzzle in establishing its affinity to other insects. Although Strepsiptera share few structural similarities with other insect orders, all members of this order share a parasitic life style with members of two distinctive families in the Coleoptera-the order now considered the most closely related to Strepsiptera based on recent genomic evidence. Among the structural features of several strepsipteran families and other insect families that have been surveyed are the organization of testes and ultrastructure of sperm cells. For comparison with existing information on insect sperm structure, this manuscript presents a description of testes and sperm of a representative of the most primitive extant strepsipteran family Mengenillidae, Eoxenos laboulbenei. We compare sperm structure of E. laboulbenei from this family with that of the three other families of Strepsiptera in the other strepsipteran suborder Stylopidia that have been studied as well as with members of the beetle families Meloidae and Rhipiphoridae that share similar life histories with Strepsiptera. Meloids, Rhipiphorids and Strepsipterans all begin larval life as active and viviparous first instar larvae. This study examines global features of these insects' sperm cells along with specific ultrastructural features of their organelles.

  12. Sperm Cells of a Primitive Strepsipteran

    PubMed Central

    Nardi, James B.; Delgado, Juan A.; Collantes, Francisco; Miller, Lou Ann; Bee, Charles M.; Kathirithamby, Jeyaraney

    2013-01-01

    The unusual life style of Strepsiptera has presented a long-standing puzzle in establishing its affinity to other insects. Although Strepsiptera share few structural similarities with other insect orders, all members of this order share a parasitic life style with members of two distinctive families in the Coleoptera—the order now considered the most closely related to Strepsiptera based on recent genomic evidence. Among the structural features of several strepsipteran families and other insect families that have been surveyed are the organization of testes and ultrastructure of sperm cells. For comparison with existing information on insect sperm structure, this manuscript presents a description of testes and sperm of a representative of the most primitive extant strepsipteran family Mengenillidae, Eoxenos laboulbenei. We compare sperm structure of E. laboulbenei from this family with that of the three other families of Strepsiptera in the other strepsipteran suborder Stylopidia that have been studied as well as with members of the beetle families Meloidae and Rhipiphoridae that share similar life histories with Strepsiptera. Meloids, Rhipiphorids and Strepsipterans all begin larval life as active and viviparous first instar larvae. This study examines global features of these insects’ sperm cells along with specific ultrastructural features of their organelles. PMID:26462430

  13. The equation of motion for sperm flagella.

    PubMed Central

    Rikmenspoel, R

    1978-01-01

    The equation of motion for sperm flagella, in which the elastic bending moment and the active contractile moment are balanced by the moment from the viscous resistance of the surrounding fluid, is solved for a wave solution that superimposes partial solutions. Substitution of the expression for the wave solution into the equation leads to an expression for the active contractile moment. This active moment can be decomposed into two parts. The first part describes an active moment that travels over the flagellum with the mechanical flagellar wave, the second part represents a moment in phase over the entire length of the flagellum, which decreases linearly towards the distal tip. The linear synchronous moment, to which an amount of traveling moment has been added as a perturbation, leads to wave solutions that closely resemble flagellar waves. Properties such as wavelength and wave amplitudes and also the shape of the waves in sea urchin sperm flagella at different frequencies are accurately described by the theory. The change in wave shape in sea urchin sperm flagella at raised viscosity is predicted well by the theory. The different wave properties caused in bull sperm flagella by different boundary conditions at the proximal junction are explained. When only a traveling active moment is present in a flagellum, the wave solutions describe waves of a small wave length in a long flagellum. Some properties of the wave motion of sperm flagella are derived from the theory and verified experimentally. Images FIGURE 17 PMID:687760

  14. Proteomic identification of rainbow trout sperm proteins.

    PubMed

    Nynca, Joanna; Arnold, Georg J; Fröhlich, Thomas; Otte, Kathrin; Ciereszko, Andrzej

    2014-06-01

    Proteomics represents a powerful tool for the analysis of fish spermatozoa, since these cells are transcriptionally inactive. The aim of the present study was to generate an inventory of the most prominent rainbow trout sperm proteins by SDS-PAGE prefractionation combined with nano-LC-MS/MS based identification. This study provides the first in-depth analysis of the rainbow trout sperm proteome, with a total of 206 identified proteins. We found that rainbow trout spermatozoa are equipped with functionally diverse proteins related to energetic metabolism, signal transduction, protein turnover, transport, cytoskeleton, oxidative injuries, and stress and reproduction. The availability of a catalog of rainbow trout sperm proteins provides a crucial tool for the understanding of fundamental molecular processes in fish spermatozoa, for the ongoing development of novel markers of sperm quality and for the optimization of short- and long-term sperm preservation procedures. The MS data are available at ProteomeXchange with the dataset identifier PXD000355 and DOI 10.6019/PXD000355.

  15. Sperm Membrane Behaviour during Cooling and Cryopreservation.

    PubMed

    Sieme, H; Oldenhof, H; Wolkers, W F

    2015-09-01

    Native sperm is only marginally stable after collection. Cryopreservation of semen facilitates transport and storage for later use in artificial reproduction technologies, but cryopreservation processing may result in cellular damage compromising sperm function. Membranes are thought to be the primary site of cryopreservation injury. Therefore, insights into the effects of cooling, ice formation and protective agents on sperm membranes may help to rationally design cryopreservation protocols. In this review, we describe membrane phase behaviour of sperm at supra- and subzero temperatures. In addition, factors affecting membrane phase transitions and stability, sperm osmotic tolerance limits and mode of action of cryoprotective agents are discussed. It is shown how cooling only results in minor thermotropic non-cooperative phase transitions, whereas freezing causes sharp lyotropic fluid-to-gel phase transitions. Membrane cholesterol content affects suprazero membrane phase behaviour and osmotic tolerance. The rate and extent of cellular dehydration coinciding with freezing-induced membrane phase transitions are affected by the cooling rate and ice nucleation temperature and can be modulated by cryoprotective agents. Permeating agents such as glycerol can move across cellular membranes, whereas non-permeating agents such as sucrose cannot. Both, permeating and non-permeating protectants preserve biomolecular and cellular structures by forming a protective glassy state during freezing. PMID:26382025

  16. Sperm Cells of a Primitive Strepsipteran.

    PubMed

    Nardi, James B; Delgado, Juan A; Collantes, Francisco; Miller, Lou Ann; Bee, Charles M; Kathirithamby, Jeyaraney

    2013-01-01

    The unusual life style of Strepsiptera has presented a long-standing puzzle in establishing its affinity to other insects. Although Strepsiptera share few structural similarities with other insect orders, all members of this order share a parasitic life style with members of two distinctive families in the Coleoptera-the order now considered the most closely related to Strepsiptera based on recent genomic evidence. Among the structural features of several strepsipteran families and other insect families that have been surveyed are the organization of testes and ultrastructure of sperm cells. For comparison with existing information on insect sperm structure, this manuscript presents a description of testes and sperm of a representative of the most primitive extant strepsipteran family Mengenillidae, Eoxenos laboulbenei. We compare sperm structure of E. laboulbenei from this family with that of the three other families of Strepsiptera in the other strepsipteran suborder Stylopidia that have been studied as well as with members of the beetle families Meloidae and Rhipiphoridae that share similar life histories with Strepsiptera. Meloids, Rhipiphorids and Strepsipterans all begin larval life as active and viviparous first instar larvae. This study examines global features of these insects' sperm cells along with specific ultrastructural features of their organelles. PMID:26462430

  17. Tracking sperm in three-dimensions.

    PubMed

    Corkidi, G; Taboada, B; Wood, C D; Guerrero, A; Darszon, A

    2008-08-15

    Sperm motility, crucial for fertilization, has been mostly studied in two dimensions (2D) by recording their swimming trajectories near a flat surface. However, spermatozoa swim in three-dimensions (3D) to find eggs, with their speed being the main impediment to track them under realistic conditions. Here, we describe a novel method allowing 3D tracking and analysis of the trajectories of multiple free-swimming sperm. The system uses a piezo-electric device displacing a large focal distance objective mounted on a microscope to acquire 70 image stacks per second, each stack composed of 60 images that span a depth of 100 microm. With this method, 3D paths of multiple sperm in the same field could be visualized simultaneously during 1 s. Within the same sample we found that surface-confined sperm swam 25% slower, produced 3-fold fewer circular revolutions per second, and had trajectories of 134% greater radius of curvature than those sperm swimming freely in 3D.

  18. Alteration of the Cortical Actin Cytoskeleton Deregulates Ca2+ Signaling, Monospermic Fertilization, and Sperm Entry

    PubMed Central

    Puppo, A.; Chun, Jong T.; Gragnaniello, Giovanni; Garante, Ezio; Santella, Luigia

    2008-01-01

    Background When preparing for fertilization, oocytes undergo meiotic maturation during which structural changes occur in the endoplasmic reticulum (ER) that lead to a more efficient calcium response. During meiotic maturation and subsequent fertilization, the actin cytoskeleton also undergoes dramatic restructuring. We have recently observed that rearrangements of the actin cytoskeleton induced by actin-depolymerizing agents, or by actin-binding proteins, strongly modulate intracellular calcium (Ca2+) signals during the maturation process. However, the significance of the dynamic changes in F-actin within the fertilized egg has been largely unclear. Methodology/Principal Findings We have measured changes in intracellular Ca2+ signals and F-actin structures during fertilization. We also report the unexpected observation that the conventional antagonist of the InsP3 receptor, heparin, hyperpolymerizes the cortical actin cytoskeleton in postmeiotic eggs. Using heparin and other pharmacological agents that either hypo- or hyperpolymerize the cortical actin, we demonstrate that nearly all aspects of the fertilization process are profoundly affected by the dynamic restructuring of the egg cortical actin cytoskeleton. Conclusions/Significance Our findings identify important roles for subplasmalemmal actin fibers in the process of sperm-egg interaction and in the subsequent events related to fertilization: the generation of Ca2+ signals, sperm penetration, cortical granule exocytosis, and the block to polyspermy. PMID:18974786

  19. Mechanics of bacteriophage maturation.

    PubMed

    Roos, Wouter H; Gertsman, Ilya; May, Eric R; Brooks, Charles L; Johnson, John E; Wuite, Gijs J L

    2012-02-14

    Capsid maturation with large-scale subunit reorganization occurs in virtually all viruses that use a motor to package nucleic acid into preformed particles. A variety of ensemble studies indicate that the particles gain greater stability during this process, however, it is unknown which material properties of the fragile procapsids change. Using Atomic Force Microscopy-based nano-indentation, we study the development of the mechanical properties during maturation of bacteriophage HK97, a λ-like phage of which the maturation-induced morphological changes are well described. We show that mechanical stabilization and strengthening occurs in three independent ways: (i) an increase of the Young's modulus, (ii) a strong rise of the capsid's ultimate strength, and (iii) a growth of the resistance against material fatigue. The Young's modulus of immature and mature capsids, as determined from thin shell theory, fit with the values calculated using a new multiscale simulation approach. This multiscale calculation shows that the increase in Young's modulus isn't dependent on the crosslinking between capsomers. In contrast, the ultimate strength of the capsids does increase even when a limited number of cross-links are formed while full crosslinking appears to protect the shell against material fatigue. Compared to phage λ, the covalent crosslinking at the icosahedral and quasi threefold axes of HK97 yields a mechanically more robust particle than the addition of the gpD protein during maturation of phage λ. These results corroborate the expected increase in capsid stability and strength during maturation, however in an unexpected intricate way, underlining the complex structure of these self-assembling nanocontainers.

  20. Third Party Reproduction: Sperm, Egg, and Embryo Donation and Surrogacy

    MedlinePlus

    ... SOCIETY FOR REPRODUCTIVE MEDICINE Third-party Reproduction Sperm, egg, and embryo donation and surrogacy A Guide for ... third-party reproduction” refers to the use of eggs , sperm , or embryos that have been donated by ...

  1. Oocyte Maturation and Development

    PubMed Central

    Verlhac, Marie-Hélène; Terret, Marie-Emilie

    2016-01-01

    Sexual reproduction is essential for many organisms to propagate themselves. It requires the formation of haploid female and male gametes: oocytes and sperms. These specialized cells are generated through meiosis, a particular type of cell division that produces cells with recombined genomes that differ from their parental origin. In this review, we highlight the end process of female meiosis, the divisions per se, and how they can give rise to a functional female gamete preparing itself for the ensuing zygotic development. In particular, we discuss why such an essential process in the propagation of species is so poorly controlled, producing a strong percentage of abnormal female gametes in the end. Eventually, we examine aspects related to the lack of centrosomes in female oocytes, the asymmetry in size of the mammalian oocyte upon division, and in mammals the direct consequences of these long-lived cells in the ovary. PMID:26998245

  2. Phagosome maturation: aging gracefully.

    PubMed Central

    Vieira, Otilia V; Botelho, Roberto J; Grinstein, Sergio

    2002-01-01

    Foreign particles and apoptotic bodies are eliminated from the body by phagocytic leucocytes. The initial stage of the elimination process is the internalization of the particles into a plasma membrane-derived vacuole known as the phagosome. Such nascent phagosomes, however, lack the ability to kill pathogens or to degrade the ingested targets. These properties are acquired during the course of phagosomal maturation, a complex sequence of reactions that result in drastic remodelling of the phagosomal membrane and contents. The determinants and consequences of the fusion and fission reactions that underlie phagosomal maturation are the topic of this review. PMID:12061891

  3. Speract, a sea urchin egg peptide that regulates sperm motility, also stimulates sperm mitochondrial metabolism.

    PubMed

    García-Rincón, Juan; Darszon, Alberto; Beltrán, Carmen

    2016-04-01

    Sea urchin sperm have only one mitochondrion, that in addition to being the main source of energy, may modulate intracellular Ca(2+) concentration ([Ca(2+)]i) to regulate their motility and possibly the acrosome reaction. Speract is a decapeptide from the outer jelly layer of the Strongylocentrotus purpuratus egg that upon binding to its receptor in the sperm, stimulates sperm motility, respiration and ion fluxes, among other physiological events. Altering the sea urchin sperm mitochondrial function with specific inhibitors of this organelle, increases [Ca(2+)]i in an external Ca(2+) concentration ([Ca(2+)]ext)-dependent manner (Ardón, et al., 2009. BBActa 1787: 15), suggesting that the mitochondrion is involved in sperm [Ca(2+)]i homeostasis. To further understand the interrelationship between the mitochondrion and the speract responses, we measured mitochondrial membrane potential (ΔΨ) and NADH levels. We found that the stimulation of sperm with speract depolarizes the mitochondrion and increases the levels of NADH. Surprisingly, these responses are independent of external Ca(2+) and are due to the increase in intracellular pH (pHi) induced by speract. Our findings indicate that speract, by regulating pHi, in addition to [Ca(2+)]i, may finely modulate mitochondrial metabolism to control motility and ensure that sperm reach the egg and fertilize it. PMID:26772728

  4. Different sperm sources and parameters can influence intracytoplasmic sperm injection outcomes before embryo implantation*

    PubMed Central

    Lu, Yue-hong; Gao, Hui-juan; Li, Bai-jia; Zheng, Ying-ming; Ye, Ying-hui; Qian, Yu-li; Xu, Chen-ming; Huang, He-feng; Jin, Fan

    2012-01-01

    To evaluate the effects of sperm with different parameters and sources on the outcomes of intracytoplasmic sperm injection (ICSI), 1972 ICSI cycles were analyzed retrospectively. Groups 1 to 5 were composed of cycles using ejaculated sperm and were grouped according to sperm quantity, quality, and morphology into normal (288 cycles), or mild (329 cycles), moderate (522 cycles), severe (332 cycles), and extremely severe (171 cycles) oligozoospermia and/or asthenozoospermia and/or teratozoospermia (OAT) groups. Group 6 was composed of 250 cycles using testicular or epididymal sperm, and Group 7 consisted of 80 cycles using frozen-thawed sperm. We found that fertilization rates were gradually reduced from Groups 1 to 6, and reached statistical difference in Groups 5 and 6 (P<0.05). The high-quality embryo rate was higher in Group 1 than in Groups 2, 3, 5, 6, and 7 (P<0.05). No statistical differences were observed in the rates of embryo cleavage, clinical pregnancy, miscarriage, live-birth, premature birth, low birth weight, weeks of premature birth, average birth weight, or sex ratio for all seven groups (P>0.05). A total of nine cases of malformation were observed, with a malformation rate of 1.25% (9/719). In conclusion, different sperm sources and parameters can affect ICSI outcomes before embryo implantation. A full assessment of offspring malformation will require further study using a larger sample size. PMID:22205614

  5. [Evaluation of Indicators of Postejaculation Maturation of Spermatozoa of Bos taurus Using a Chlortetracycline Test].

    PubMed

    Boitseva, E N; Denisenko, V Yu; Kuz'mina, T I

    2015-01-01

    Postejaculation maturation of spermatozoa (capacitation and acrosomal exocytosis) in bovine sperm was assessed using the method of staining with chlortetracycline and inhibitor analysis to identify the transition ways of calcium of intracellular depots under the influence of highly dispersed silica. It was shown that highly dispersed silica in a concentration of 0.001% stimulates capacitation but has no impact on the acrosome exocytosis in bovine sperm. Activated by highly dispersed silica, capacitation was inhibited in the presence of cytochalasin D and H-89 inhibitors, whereas nocodazole and Ro 31-8220 had no influence on this process. The joint action of theophylline and guanosine diphosphate stimulates an increase in the amount of capacitated sperm cells, similarly to highly dispersed silica; inhibitors cytochalasin D and H-89 restrict the capacitation of sperm activated by these compounds. At the same time, the joint effect of prolactin and guanosine triphosphate had no effect on the capacitation of spermatozoa; addition of nocodazole and Ro 31-8220 inhibitors did not alter the effect of prolactin and guanosine triphosphate on the capacitation of sperm. A hypothesis was put forward, according to which increase in the cryoresistance of spermatozoa of bulls under the influence of highly dispersed silica is, apparently, determined by the transition of Ca2+ between the intracellular stores in the direction from inositol triphosphate-sensitive to inositol triphosphate-insensitive intracellular stores of calcium. The obtained data allow us to expand the notion of the biochemical mechanisms of capacitation in the spermatozoa of bulls.

  6. Sperm traits in farmed and wild Atlantic salmon Salmo salar.

    PubMed

    Camarillo-Sepulveda, N; Hamoutene, D; Lush, L; Burt, K; Volkoff, H; Fleming, I A

    2016-02-01

    Differences in sperm metabolism and morphology between wild and non-local farmed Atlantic salmon Salmo salar were assessed by measuring metabolic enzyme activities and length of sperm flagella. No differences were observed between wild and farmed S. salar sperm with regards to cell counts or any of the biochemical variables assessed. Flagella of sperm cells were significantly longer in wild than farmed S. salar; however, this did not result in higher energy levels or different fertilization rates. PMID:26549612

  7. Sperm traits in farmed and wild Atlantic salmon Salmo salar.

    PubMed

    Camarillo-Sepulveda, N; Hamoutene, D; Lush, L; Burt, K; Volkoff, H; Fleming, I A

    2016-02-01

    Differences in sperm metabolism and morphology between wild and non-local farmed Atlantic salmon Salmo salar were assessed by measuring metabolic enzyme activities and length of sperm flagella. No differences were observed between wild and farmed S. salar sperm with regards to cell counts or any of the biochemical variables assessed. Flagella of sperm cells were significantly longer in wild than farmed S. salar; however, this did not result in higher energy levels or different fertilization rates.

  8. Spermatogenesis and sperm ultrastructure in the polychaete genus Ophryotrocha (Dorvilleidae)

    NASA Astrophysics Data System (ADS)

    Pfannenstiel, Hans-Dieter; Grünig, Charlotte

    1990-06-01

    The details of spermatogenesis and spermiogenesis are described for Ophryotrocha puerilis. The ultrastructure of mature sperm is shown for O. puerilis, O. hartmanni, O. gracilis, O. diadema, O. labronica, and O. notoglandulata. Clusters of sixteen cells each are proliferated by two stem cells in each setigerous segment of O. puerilis representing the very early stages of both oogenesis and spermatogenesis. In each spermatocyte-I cluster, the cells are interconnected by cytoplasmic bridges. Early, clusters are enveloped by peritoneal sheath cells. These transient gonad walls break down prior to meiosis. The meiotic processes may start in the clusters with the cells still interconnected, or during breakdown of the original cluster, giving rise to smaller subclusters of both spermatocytes I and spermatocytes II with various numbers of cells. Finally, spermatid tetrads are present. As spermiogenesis progresses, the tetrads disintegrate. Golgi vesicles in both spermatocytes and spermatids contain electron-dense material, presumably preacrosomal. The acrosome is formed by such vesicles. In the six species studied here, the acrosomes appear to be of a similar overall structure but are of different shape. Centrioles are usually located beneath the acrosome. The distal centriole forms the basal body of a flagellum-like cytoplasmic process. The microtubules of these flagellar equivalents do not show a normal ciliar arrangement. The flagellar equivalent appears to be non-motile. In O. hartmanni and in O. notoglandulata, a flagellar equivalent is missing. Microtubules originating from the proximal end of the distal centriole stretch to the nuclear envelope. This feature appears to be especially conspicuous in O. puerilis and in O. labronica. In O. labronica and in O. notoglandulata, bundles of microtubules paralleling the cell perimeter appear to stabilise the sperm. Various numbers of mitochondria are either randomly distributed around the nucleus or accumulate on one side

  9. Sperm preparation: state-of-the-art—physiological aspects and application of advanced sperm preparation methods

    PubMed Central

    Henkel, Ralf

    2012-01-01

    For assisted reproduction technologies (ART), numerous techniques were developed to isolate spermatozoa capable of fertilizing oocytes. While early methodologies only focused on isolating viable, motile spermatozoa, with progress of ART, particularly intracytoplasmic sperm injection (ICSI), it became clear that these parameters are insufficient for the identification of the most suitable spermatozoon for fertilization. Conventional sperm preparation techniques, namely, swim-up, density gradient centrifugation and glass wool filtration, are not efficient enough to produce sperm populations free of DNA damage, because these techniques are not physiological and not modeled on the stringent sperm selection processes taking place in the female genital tract. These processes only allow one male germ cell out of tens of millions to fuse with the oocyte. Sites of sperm selection in the female genital tract are the cervix, uterus, uterotubal junction, oviduct, cumulus oophorus and the zona pellucida. Newer strategies of sperm preparation are founded on: (i) morphological assessment by means of ‘motile sperm organelle morphological examination (MSOME)' (ii) electrical charge; and (iii) molecular binding characteristics of the sperm cell. Whereas separation methods based on electrical charge take advantage of the sperm's adherence to a test tube surface or separate in an electrophoresis, molecular binding techniques use Annexin V or hyaluronic acid (HA) as substrates. Techniques in this category are magnet-activated cell sorting, Annexin V-activated glass wool filtration, flow cytometry and picked spermatozoa for ICSI (PICSI) from HA-coated dishes and HA-containing media. Future developments may include Raman microspectrometry, confocal light absorption and scattering spectroscopic microscopy and polarization microscopy. PMID:22138904

  10. Eliminating the effect of pathomorphologically formed sperm on resulting gravidity using the intracytoplasmic sperm injection method.

    PubMed

    Blahová, Eva; Máchal, Jan; Máchal, Ladislav; Milaković, Irena; Hanuláková, Sárka

    2014-04-01

    The aim of the present study was to test whether it is possible to eliminate a high percentage of morphologically abnormal sperm in male ejaculate by assisted reproduction using the intracytoplasmic sperm injection (ICSI) method. Treatment success was evaluated by comparing fertilization, clinical pregnancy and reproduction rates between males with heavy teratospermia (≤1% morphologically normal spermatozoa) and males with a higher percentage (>1%) of normal sperm. In total, 174 patients who had previously undergone 174 ICSI cycles (1 per each pair) were evaluated retrospectively. In the group of patients with heavily impaired sperm morphology (n=37), the percentage of normal spermatozoa was ≤1%. In the second group, males with >1% normal spermatozoa (n=137) were considered as patients with mildly impaired sperm morphology. The results of partner fertilization in these two groups were compared and a lower number of fertilized oocytes was identified in the patients with heavily impaired sperm morphology (P=0.038). However, neither the gravidity nor the take-home baby rates of the partners differed between the patients with mildly and heavily impaired sperm morphology. Trends opposite to that for fertilization were observed for gravidity and delivery [odds ratio (OR), 0.62; 95% confidence interval (CI), 0.29-1.30; OR, 0.55; 95% CI, 0.26-1.24, respectively]. This indicates that the lower number of fertilized oocytes was not associated with the overall outcome of fertilization and that patients with heavily impaired sperm morphology experience the same benefit from ICSI as patients with mildly impaired sperm morphology.

  11. Sound production in neonate sperm whales (L)

    NASA Astrophysics Data System (ADS)

    Madsen, P. T.; Carder, D. A.; Au, W. W. L.; Nachtigall, P. E.; Møhl, B.; Ridgway, S. H.

    2003-06-01

    Acoustic data from two sperm whale neonates (Physeter macrocephalus) in rehabilitation are presented and implications for sound production and function are discussed. The clicks of neonate sperm whale are very different from usual clicks of adult specimens in that neonate clicks are of low directionality [SL anomaly (0°-90°) <8 dB], long duration (2-12 ms), and low frequency (centroid frequency between 300 and 1700 Hz) with estimated SLs between 140 and 162 dB//1 μPa (rms). Such neonate clicks are unsuited for biosonar, but can potentially convey homing information between calves and submerged conspecifics in open ocean waters at ranges of some 2 km. Moreover, it is demonstrated that sperm whale clicks are produced at the anterior placed monkey lips, thereby substantiating a key point in the modified Norris and Harvey theory and supporting the unifying theory of sound production in odontocetes.

  12. Detection of chromosomal abnormalities in human sperm

    SciTech Connect

    Brandriff, B.; Gordon, L.; Ashworth, A.K.; Watchmaker, G.; Carrano, A.V.

    1985-06-19

    A new technology developed by Rudak, et al. for examining the chromosomal constitution of human sperm through fusion with eggs from the Syrian hamster was used to obtain baseline data on the types and frequencies of aberrations in sperm of normal men. The frequency of structural aberrations in 2724 sperm chromosome karyotypes from the 13 healthy non-exposed donors ranged from 2 to 15.8%, demonstrating significant interindividual variability. The most frequently occurring aberrations were chromosome breaks, followed by acentric fragments, chromatid exchanges, chromatid breaks, dicentrics and translocations, chromosome deletions and duplications, inversions, and chromatid deletions. Two donors previously reported had one cell each with multiple chromatid exchanges and breaks. In addition, the oldest donor, AA, had 5 cells out of 124 examined with multiple breaks and rearrangements too extensive to completely identify. 17 refs., 2 tabs.

  13. LOCALIZATION OF SP22 ON HUMAN SPERM OF DIFFERING QUALITY

    EPA Science Inventory

    LOCALIZATION OF SP22 ON HUMAN SPERM OF DIFFERING QUALITY. AE Lavers*1, GR Klinefelter2, DW Hamilton1, KP Roberts1, 1University of Minnesota, Minneapolis, MN and 2US EPA, Research Triangle Park, NC.
    SP22 is a sperm membrane protein that has been implicated in sperm function d...

  14. Ovarian fluid of receptive females enhances sperm velocity.

    PubMed

    Gasparini, Clelia; Andreatta, Gabriele; Pilastro, Andrea

    2012-05-01

    The females of several internal fertilizers are able to store sperm for a long time, reducing the risk of sperm limitation. However, it also means that males can attempt to mate outside females' receptive period, potentially increasing the level of sperm competition and exacerbating sexual conflict over mating. The guppy (Poecilia reticulata), an internally fertilizing fish, is a model system of such competition and conflict. Female guppies accept courtship and mate consensually only during receptive periods of the ovarian cycle but receive approximately one (mostly forced) mating attempt per minute both during and outside their sexually receptive phase. In addition, females can store viable sperm for months. We expected that guppy females would disfavour sperm received during their unreceptive period, possibly by modulating the quality and/or quantity of the components present in the ovarian fluid (OF) over the breeding cycle. Ovarian fluid has been shown to affect sperm velocity, a determinant of sperm competition success in this and other fishes. We found that in vitro sperm velocity is slower in OF collected from unreceptive females than in OF from receptive females. Visual stimulation with a potential partner prior to collection did not significantly affect in vitro sperm velocity. These results suggest that sperm received by unreceptive females may be disfavoured as sperm velocity likely affects the migration process and the number of sperm that reach storage sites.

  15. Ovarian fluid of receptive females enhances sperm velocity.

    PubMed

    Gasparini, Clelia; Andreatta, Gabriele; Pilastro, Andrea

    2012-05-01

    The females of several internal fertilizers are able to store sperm for a long time, reducing the risk of sperm limitation. However, it also means that males can attempt to mate outside females' receptive period, potentially increasing the level of sperm competition and exacerbating sexual conflict over mating. The guppy (Poecilia reticulata), an internally fertilizing fish, is a model system of such competition and conflict. Female guppies accept courtship and mate consensually only during receptive periods of the ovarian cycle but receive approximately one (mostly forced) mating attempt per minute both during and outside their sexually receptive phase. In addition, females can store viable sperm for months. We expected that guppy females would disfavour sperm received during their unreceptive period, possibly by modulating the quality and/or quantity of the components present in the ovarian fluid (OF) over the breeding cycle. Ovarian fluid has been shown to affect sperm velocity, a determinant of sperm competition success in this and other fishes. We found that in vitro sperm velocity is slower in OF collected from unreceptive females than in OF from receptive females. Visual stimulation with a potential partner prior to collection did not significantly affect in vitro sperm velocity. These results suggest that sperm received by unreceptive females may be disfavoured as sperm velocity likely affects the migration process and the number of sperm that reach storage sites. PMID:22430815

  16. Cryopreservation of sperm in farmed Australian greenlip abalone Haliotis laevigata.

    PubMed

    Liu, Yibing; Xu, Tong; Robinson, Nicholas; Qin, Jianguang; Li, Xiaoxu

    2014-04-01

    This study investigated factors important to the development of the liquid nitrogen (LN) vapor sperm cryopreservation technique in farmed greenlip abalone Haliotis laevigata, including (1) cryoprotectant agent (CPA) toxicity; (2) cooling temperature (height above LN surface); (3) thawing temperature; (4) sperm to egg ratio; and (5) sugar supplementation, using sperm motility, fertilization rate or integrity/potential of sperm components and organelles as quality assessment indicators. Results suggested that among the single CPAs evaluated 6% dimethyl sulfoxide (Me2SO) would be the most suitable for sperm cryopreservation in this species. The highest post-thaw sperm motility was achieved with the sperm that had been exposed to LN vapor for 10min at 5.2cm above the LN surface, thawed and recovered in 60 and 18°C seawater bathes, respectively after at least 2h storage in LN. The highest fertilization rates were achieved at a sperm to egg ratio of 10,000:1 or 15,000:1. Addition of 1% glucose or 2% sucrose produced significantly higher post-thaw sperm motility than 6% Me2SO alone. Among the three cryoprotectant solutions further trialled, 6% Me2SO+1% glucose produced the highest fertilization rate of 83.6±3.7%. Evaluation of sperm has shown that the addition of glucose could significantly improve the sperm plasma membrane integrity and mitochondrial membrane potential. These results demonstrated a positive role of glucose in the improvement of sperm cryopreservation in farmed greenlip abalone. PMID:24440870

  17. Effect of testicle postmortem storage on goat frozen-thawed epididymal sperm quality as a tool to improve genebanking in local breeds.

    PubMed

    Turri, F; Madeddu, M; Gliozzi, T M; Gandini, G; Pizzi, F

    2014-03-01

    The interest to develop assisted reproductive technologies and cryobanking for farm animal genetic resource conservation has recently increased. However, cryopreservation for ex-situ management of genetic diversity sometimes is not routinely feasible, owing to the lack of facilities (AI centres, laboratories) and expertise near the local breed farming area. In these cases, epididymal sperm obtained from slaughtered or castrated animals, associated with the possibility of managing rather long periods between animal death, sperm recovery and freezing, would increase the opportunities to create semen storages. This investigation addresses the pre-freeze/post-thaw quality of goat epididymal sperm as a function of testicle storage temperature (environment or +5°C) and time elapsed between animal's death and sperm recovery (0, 24, 48, 72 h) to establish the optimal protocols for the recovery and cryopreservation of epididymal sperm in this species. Testicles of 50 mature bucks collected at the abattoir were divided in two groups: half of the testicles (n=50) were transported to the laboratory at environment temperature (E), whereas the remaining half (n=50) at a refrigeration temperature (R) of +5°C. In the two groups (E) and (R), one testicle from each pair was processed after slaughter forming the time 0 groups (0E and 0R). The contralateral testicle was processed after 24, 48 or 72 h of storage, at the corresponding temperature. Sperm motility and kinetic parameters, viability and morphology were assessed in pre-freeze and post-thaw samples. Until 48 h postmortem, both E and R temperatures are able to maintain good pre-freeze epididymal sperm quality. After 48 h postmortem, R temperature is fundamental to reduce epididymal sperm quality decay in pre-freeze samples. Moreover, testicle refrigeration also has a positive impact on post-thaw samples, allowing a lower decline through time considering total motility, kinetics parameters, sperm viability and sperm

  18. Predictive capacity of sperm quality parameters and sperm subpopulations on field fertility after artificial insemination in sheep.

    PubMed

    Santolaria, P; Vicente-Fiel, S; Palacín, I; Fantova, E; Blasco, M E; Silvestre, M A; Yániz, J L

    2015-12-01

    This study was designed to evaluate the relevance of several sperm quality parameters and sperm population structure on the reproductive performance after cervical artificial insemination (AI) in sheep. One hundred and thirty-nine ejaculates from 56 adult rams were collected using an artificial vagina, processed for sperm quality assessment and used to perform 1319 AI. Analyses of sperm motility by computer-assisted sperm analysis (CASA), sperm nuclear morphometry by computer-assisted sperm morphometry analysis (CASMA), membrane integrity by acridine orange-propidium iodide combination and sperm DNA fragmentation using the sperm chromatin dispersion test (SCD) were performed. Clustering procedures using the sperm kinematic and morphometric data resulted in the classification of spermatozoa into three kinematic and three morphometric sperm subpopulations. Logistic regression procedures were used, including fertility at AI as the dependent variable (measured by lambing, 0 or 1) and farm, year, month of AI, female parity, female lambing-treatment interval, ram, AI technician and sperm quality parameters (including sperm subpopulations) as independent factors. Sperm quality variables remaining in the logistic regression model were viability and VCL. Fertility increased for each one-unit increase in viability (by a factor of 1.01) and in VCL (by a factor of 1.02). Multiple linear regression analyses were also performed to analyze the factors possibly influencing ejaculate fertility (N=139). The analysis yielded a significant (P<0.05) relationship between sperm viability and ejaculate fertility. The discriminant ability of the different semen variables to predict field fertility was analyzed using receiver operating characteristic (ROC) curve analysis. Sperm viability and VCL showed significant, albeit limited, predictive capacity on field fertility (0.57 and 0.54 Area Under Curve, respectively). The distribution of spermatozoa in the different subpopulations was not

  19. The proportion of beef bulls in western Canada with mature spermiograms at 11 to 15 months of age.

    PubMed Central

    Arteaga, A; Baracaldo, M; Barth, A D

    2001-01-01

    A study was conducted to determine the proportion of yearling beef bulls that have mature spermiograms at 11 to 15 months of age, and to evaluate the relationship between semen quality traits, age, and scrotal circumference. Semen samples and data on sperm motility and scrotal circumference measurements were obtained from 1641 bulls of 14 breeds. Criteria for a satisfactory spermiogram included sperm concentration > or = 400 x 10(6)/mL, > or = 60% progressively motile sperm, and > or = 70% morphologically normal sperm. The mean scrotal circumference measurements for all bulls combined were 33.4, 34.4, 35.2, 35.8, and 35.3 cm at 11, 12, 13, 14, and 15 months of age, respectively. The percentage of bulls with matures spermiograms at 11, 12, 13, 14, and 15 months of age were 20%, 30%, 51%, 52%, and 61%, respectively. There was a high positive correlation (r = 0.9) between the number of bulls with > or = 70% normal sperm and scrotal circumference measurement. The main types of morphologic defects observed in immature bulls were proximal droplets and midpiece defects. PMID:11665426

  20. Optimization of the sperm:oocyte ratio and sperm economy in the artificial reproduction of Rhamdia quelen using fructose as a sperm motility modulator.

    PubMed

    Adames, Maurício Spagnolo; de Toledo, Cesar Pereira Rebechi; Neumann, Giovano; Buzzi, Alexandre Henrique; Buratto, Cíntia Nara; Piana, Pitágoras Augusto; Bombardelli, Robie Allan

    2015-10-01

    This research was conducted to evaluate the effects of fructose as a modulator of sperm motility and its effects on the reduction in number of sperm cells in IVF using cryopreserved Rhamdia quelen semen. Sperm activation occurred in solutions containing fructose (0.0, 0.9, 1.8, 2.7, 3.6 and 4.5%). The sperm motility rate, velocity and duration of sperm motility were assessed by polynomial regression analysis and grouped by the principal component analysis (PCA). Then, the oocytes were mixed with semen at proportions of 1×10(4), 3×10(4), 5×10(4), 7×10(4) and 9×10(4) for the sperm:oocyte ratio and fertilization was induced by the activation of gametes with the fructose-containing solutions. The fertilization, hatching and larval normality rate were evaluated by response surface protocol and were further grouped by PCA. All sperm variables were affected by the activating solutions, and the most desirable theoretical results for the rate of sperm motility were obtained when using a solution containing 2.85% fructose. In the IVF and incubation assays, there was an interactive effect between the motile sperm:oocyte ratio and the fructose concentration on the rates of oocyte fertilization, hatching and on the clustered index for reproductive success. The results suggest the possibility of reducing the sperm cells on IVF by 17.77% when using a solution containing 2.28% fructose. In conclusion, the use of solutions containing fructose at concentrations that maximize sperm movement allow the reduction of the motile sperm:oocyte ratio, thus promoting sperm metabolic efficiencies and contributing to the feasibility of using cryopreserved semen at a large-scale in IVF. PMID:26364705

  1. Optimization of the sperm:oocyte ratio and sperm economy in the artificial reproduction of Rhamdia quelen using fructose as a sperm motility modulator.

    PubMed

    Adames, Maurício Spagnolo; de Toledo, Cesar Pereira Rebechi; Neumann, Giovano; Buzzi, Alexandre Henrique; Buratto, Cíntia Nara; Piana, Pitágoras Augusto; Bombardelli, Robie Allan

    2015-10-01

    This research was conducted to evaluate the effects of fructose as a modulator of sperm motility and its effects on the reduction in number of sperm cells in IVF using cryopreserved Rhamdia quelen semen. Sperm activation occurred in solutions containing fructose (0.0, 0.9, 1.8, 2.7, 3.6 and 4.5%). The sperm motility rate, velocity and duration of sperm motility were assessed by polynomial regression analysis and grouped by the principal component analysis (PCA). Then, the oocytes were mixed with semen at proportions of 1×10(4), 3×10(4), 5×10(4), 7×10(4) and 9×10(4) for the sperm:oocyte ratio and fertilization was induced by the activation of gametes with the fructose-containing solutions. The fertilization, hatching and larval normality rate were evaluated by response surface protocol and were further grouped by PCA. All sperm variables were affected by the activating solutions, and the most desirable theoretical results for the rate of sperm motility were obtained when using a solution containing 2.85% fructose. In the IVF and incubation assays, there was an interactive effect between the motile sperm:oocyte ratio and the fructose concentration on the rates of oocyte fertilization, hatching and on the clustered index for reproductive success. The results suggest the possibility of reducing the sperm cells on IVF by 17.77% when using a solution containing 2.28% fructose. In conclusion, the use of solutions containing fructose at concentrations that maximize sperm movement allow the reduction of the motile sperm:oocyte ratio, thus promoting sperm metabolic efficiencies and contributing to the feasibility of using cryopreserved semen at a large-scale in IVF.

  2. Cryopreservation of Iberian pig spermatozoa. Comparison of different freezing extenders based on post-thaw sperm quality.

    PubMed

    De Mercado, Eduardo; Rodríguez, Ana; Gómez, Emilio; Sanz, Elena

    2010-03-01

    The aim of this study was to evaluate the cryoprotective effect of different freezing extenders against cryopreservation injuries on Iberian boar sperm. The sperm-rich fraction was collected and pooled from six sexually mature Iberian boars, and was frozen in different extenders containing glucose, lactose or fructose as sugar source and including Orvus ES Paste only in the freezing extender-2 (Glucose; Lactose and Fructose) or in both freezing extenders (Glucose2; Lactose2 and Fructose2). During the cryopreservation process, the supernatant was removed after the centrifugation step, then was extended with freezing extender-1 for the equilibration period and with freezing extender-2 immediately before freezing. Post-thaw sperm characteristics, such as plasma membrane integrity (SYBR-14/PI), mitochondrial function (Rhodamine 123) and acrosome integrity (NAR), were monitored. Overall sperm motility and the individual kinematic parameters of motile spermatozoa (assessed by the computer-aided sperm analysis system Sperm Class Analyzer [SCA]) were recorded in the different experimental treatments. Measurements were taken at 30 and 150 min post-thaw. The state of the acrosome after thawing did not show significant differences between the freezing extenders studied. Freezing-thawing caused a significant decrease (P<0.001) in plasma membrane integrity and in mitochondrial activity in the spermatozoa frozen with Orvus ES Paste in both freezing extenders. Furthermore, spermatozoa frozen with Orvus ES Paste in both freezing extenders exhibited lower (P<0.05) motility and kinematic parameters than those frozen in the absence of Orvus ES Paste in the first freezing extender. The spermatozoa frozen with the Lactose extender and with Orvus ES Paste only in the second freezing extender showed a better evolution of the motility and kinematic characteristics (P<0.05) over time. The deterioration in post-thaw sperm motility and kinematic parameters were concurrent with reduced sperm

  3. Interaction of resident sperm with sperm-storage tubule (SST) epithelial cell microvilli in the turkey hen

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Unlike most mammals, birds do not need to synchronize copulation with ovulation. Hens are endowed with tubular structures, the sperm-storage tubules (SST), in their oviducts which the sperm enter and survive for weeks after mating or artificial insemination. Sperm are slowly but continually releas...

  4. Exogenous neurotensin modulates sperm function in Japanese Black cattle

    PubMed Central

    UMEZU, Kohei; HIRADATE, Yuuki; OIKAWA, Toshinori; ISHIGURO, Hirotoshi; NUMABE, Takashi; HARA, Kenshiro; TANEMURA, Kentaro

    2016-01-01

    Recently, the conception rates after artificial insemination have been pointed out to decline continuously. To overcome this problem, the control of frozen and thawed sperm quality is required. However, the mechanism of bovine sperm functional regulation is still largely unknown. In mammals, the ejaculated sperm are capable of showing fertilizing ability during migration in the female reproductive organs. It is well known that these female organs secrete several factors contributing to sperm capacitation. We previously reported that neurotensin (NT) secreted from the oviduct and cumulus cells enhanced sperm capacitation and acrosome reaction in mice. In this study, we confirmed the expression of the NT receptor (NTR1) in the bovine sperm neck region and the secretion of NT in the bovine uterus and oviduct. The similar expression patterns of NT and NTR1 suggests a conserved mechanism of sperm functional regulation between mouse and cattle. Thus, we examined the effects of exogenous NT on the bovine sperm functions. First, we showed that NT induced sperm protein tyrosine phosphorylation in a dose-dependent manner, suggesting that NT enhances sperm capacitation. Second, we showed that NT induced acrosome reactions of capacitated sperm in a dose-dependent manner, suggesting that NT facilitates acrosome reaction. Finally, we used a computer-aided sperm analysis system to show that NT did not have a great effect on sperm motility. These results suggest that NT acts as a facilitator of sperm capacitation and acrosome reaction in the female reproductive tracts in cattle, highlighting the importance of NT-mediated signaling to regulate sperm functions. PMID:27210588

  5. Exogenous neurotensin modulates sperm function in Japanese Black cattle.

    PubMed

    Umezu, Kohei; Hiradate, Yuuki; Oikawa, Toshinori; Ishiguro, Hirotoshi; Numabe, Takashi; Hara, Kenshiro; Tanemura, Kentaro

    2016-08-25

    Recently, the conception rates after artificial insemination have been pointed out to decline continuously. To overcome this problem, the control of frozen and thawed sperm quality is required. However, the mechanism of bovine sperm functional regulation is still largely unknown. In mammals, the ejaculated sperm are capable of showing fertilizing ability during migration in the female reproductive organs. It is well known that these female organs secrete several factors contributing to sperm capacitation. We previously reported that neurotensin (NT) secreted from the oviduct and cumulus cells enhanced sperm capacitation and acrosome reaction in mice. In this study, we confirmed the expression of the NT receptor (NTR1) in the bovine sperm neck region and the secretion of NT in the bovine uterus and oviduct. The similar expression patterns of NT and NTR1 suggests a conserved mechanism of sperm functional regulation between mouse and cattle. Thus, we examined the effects of exogenous NT on the bovine sperm functions. First, we showed that NT induced sperm protein tyrosine phosphorylation in a dose-dependent manner, suggesting that NT enhances sperm capacitation. Second, we showed that NT induced acrosome reactions of capacitated sperm in a dose-dependent manner, suggesting that NT facilitates acrosome reaction. Finally, we used a computer-aided sperm analysis system to show that NT did not have a great effect on sperm motility. These results suggest that NT acts as a facilitator of sperm capacitation and acrosome reaction in the female reproductive tracts in cattle, highlighting the importance of NT-mediated signaling to regulate sperm functions. PMID:27210588

  6. Evaluation of human sperm function after repeated freezing and thawing.

    PubMed

    Bandularatne, Enoka; Bongso, Ariff

    2002-01-01

    Sperm storage via freezing has been useful for men who have difficulty masturbating during assisted reproductive technology (ART) programs and before impotency caused by chemotherapy, vasectomy, and other procedures. Studies were undertaken to evaluate the extent of cryoinjury to sperm after repeated freezing and thawing. The results showed that normozoospermic and oligozoospermic sperm survived after 3 repeated freeze-thaw cycles. The inclusion of seminal plasma did not seem to protect human sperm during freezing and thawing. There were no significant differences in recovery percentages for motile, vital, and morphologically normal sperm between slow and rapid freezing methods in thaws 1, 2, and 3 of normozoospermic and oligozoospermic unwashed (u), washed (w), and washed + seminal plasma (ws) samples. However, there were significant percentage drops in the recovery of motile and vital sperm between each thaw (ie, first to second thaw, and second to third thaw) using both slow and rapid freezing for u, w, and ws samples (P < .01). There were also no significant differences in percentage recovery of motile, vital, and morphologically normal sperm between u, w, and ws samples during thaws 1 to 3 in the normozoospermic and oligozoospermic groups. Sperm were capable of fertilizing hamster oocytes microinjected with single sperms after 3 freeze-thaw cycles as evidenced by the formation of 2 distinct pronuclei and 2 polar bodies in 22.2% and 17.2% of normozoospermic and oligozoospermic samples, respectively. The numbers of normal vital motile sperm after 3 serial freeze-thaw cycles are adequate for bringing about fertilization via intracytoplasmic sperm injection in ART programs. Thus, leftover washed sperm in laboratories that perform in vitro fertilization can be frozen, thawed, and refrozen several times without loss of the sperms' ability to fertilize. This approach has tremendous benefits for men who have difficulty producing sperm and for those with low and

  7. The 12 kD FK 506 binding protein FKBP12 is released in the male reproductive tract and stimulates sperm motility.

    PubMed Central

    Walensky, L. D.; Dawson, T. M.; Steiner, J. P.; Sabatini, D. M.; Suarez, J. D.; Klinefelter, G. R.; Snyder, S. H.

    1998-01-01

    BACKGROUND: The 12 kD FK506 binding protein FKBP12 is a cytosolic receptor for the immunosuppressant drugs FK506 and rapamycin. In addition to its critical role in drug-induced T-cell immunosuppression, FKBP12 associates physiologically with ryanodine and inositol 1,4,5-trisphosphate (IP3) receptors, regulating their ability to flux calcium. We investigated a role for FKBP12 in male reproductive physiology on the basis of our identification of extremely high levels of [3H]FK506 binding in male reproductive tissues. MATERIALS AND METHODS: [3H]FK506 binding studies were performed to identify tissues enriched with FK506 binding sites. The abundant [3H]FK506 binding sites identified in the male reproductive tract were localized by [3H]FK506 autoradiography. FK506 affinity chromatography was employed to purify FKBP from epididymal fluid. Anti-FKBP12 Western analysis was used to confirm the identity of the purified FKBP. The binding of exogenous FKBP12 to sperm was evaluated by [32P]FKBP12 binding studies and [33P]FKBP12 autoradiography. The effect of recombinant FKBP12 on sperm motility was investigated using a Hamilton Thorne motility analyzer. RESULTS: Male reproductive tissues contained high levels of [3H]FK506 binding. The localization of [3H]FK506 binding sites to the tubular epithelium of the caput epididymis and the lumen of the cauda and vas deferens suggested that FKBP is released in the male reproductive tract. FKBP12 was purified from epididymal plasma by FK506 affinity chromatography. Radiolabeled FKBP12 specifically bound to immature but not mature sperm. In sperm motility studies, FKBP12-treated caput sperm exhibited double the curvilinear velocity of untreated controls. CONCLUSIONS: High levels of FKBP12 are released in the male reproductive tract and specifically associate with maturing sperm. Recombinant FKBP12 enhances the curvilinear velocity of immature sperm, suggesting a role for FKBP12 in motility initiation. The highest concentrations of soluble

  8. Seminal plasma effects on sex-sorting bovine sperm.

    PubMed

    Burroughs, C A; Graham, J K; Lenz, R W; Seidel, G E

    2013-02-01

    The objective was to determine which characteristics of bovine ejaculates affected efficacy of sex sorting bovine sperm by flow cytometry. The effects of first versus second ejaculates, seminal plasma content, addition of BSA, and seminal plasma from different bulls during staining were all studied, as was the effect of 8-hour storage with and without seminal plasma. Semen collected by artificial vagina was centrifuged at 1000 ×g for 15 minutes to separate sperm from seminal plasma; seminal plasma was clarified by 10 minutes of additional centrifugation at 2000 ×g. Sperm were rediluted to 160 × 10(6) sperm per mL with: Tyrode's medium plus albumin, lactate, and pyruvate (TALP) containing 0%, 5%, 10%, or 20% homologous seminal plasma, TALP containing 10% heterologous seminal plasma, or TALP containing 0.3% (control), 0.6%, or 1.2% BSA. After incubation with Hoechst 33342 for 45 minutes, an equal volume of TALP containing red food dye was added, and sperm were analyzed by flow cytometry/cell sorting to determine percent of live-oriented sperm, X sort rate, percent of membrane-impaired sperm, and split (degree of separation between X- and Y-bearing sperm populations). The percent of live-oriented sperm was higher for sperm incubated with 0% seminal plasma (64%) than for sperm incubated with 5%, 10%, or 20% seminal plasma (60%, 59%, and 58%, respectively; P < 0.05). The X sort rate was higher for sperm incubated with 0% seminal plasma than sperm with 20% seminal plasma (4.26 vs. 3.61 × 10(3) sperm per second). When seminal plasma was exchanged between bull ejaculates, only one bull had seminal plasma that was detrimental to sperm, resulting in 31% membrane-impaired sperm compared with a range of 16% to 19% for seminal plasmas from other bulls (P < 0.05). The addition of BSA did not affect sort efficiency at the concentrations studied. Sperm from six bulls stored for 8 hours without seminal plasma had more membrane-impaired sperm (which were discarded) during

  9. Cytogenetics of human sperm: Structural aberrations and DNA replication

    SciTech Connect

    Brandriff, B.F.; Gordon, L.A.; Carrano, A.V.

    1989-07-11

    The human sperm-hamster egg system, first introduced in 1978 (Rudak et al), has yielded some important insights into questions on chromosomal integrity of human sperm. In this system, human sperm are co-incubated with eggs from the golden hamster. After the gametes fuse, eggs are cultured overnight and approximately 15 hours after fusion, display the haploid chromosomal complement of individual human sperm cells. These chromosomes can be analyzed by standard banding techniques to identify and quantify structural and numerical abnormalities in single sperm. 32 refs., 1 fig.

  10. Cytometry of deoxyribonuclei acid content and morphology of mammalian sperm

    SciTech Connect

    Gledhill, B.L.

    1983-01-01

    Because spermatogenesis is exquisitely sensitive to external influences, sperm can serve as a biological dosimeter. Advances in interpreting induced sperm abnormalities require a better understanding of sperm characteristics. This report reviews the application of several methods for automated, quantitative detection of shape changes, methods that are faster and more sensitive than conventional subjective technqiues. Variability of sperm deoxyribonucleic acid content as a bioassay of genetic damage is explored, and limitations of the bioassay are discussed. New flow cytometric techniques that could lead to sexing mammalian sperm are examined.

  11. Direct action of endocrine disrupting chemicals on human sperm.

    PubMed

    Schiffer, Christian; Müller, Astrid; Egeberg, Dorte L; Alvarez, Luis; Brenker, Christoph; Rehfeld, Anders; Frederiksen, Hanne; Wäschle, Benjamin; Kaupp, U Benjamin; Balbach, Melanie; Wachten, Dagmar; Skakkebaek, Niels E; Almstrup, Kristian; Strünker, Timo

    2014-07-01

    Synthetic endocrine disrupting chemicals (EDCs), omnipresent in food, household, and personal care products, have been implicated in adverse trends in human reproduction, including infertility and increasing demand for assisted reproduction. Here, we study the action of 96 ubiquitous EDCs on human sperm. We show that structurally diverse EDCs activate the sperm-specific CatSper channel and, thereby, evoke an intracellular Ca(2+) increase, a motility response, and acrosomal exocytosis. Moreover, EDCs desensitize sperm for physiological CatSper ligands and cooperate in low-dose mixtures to elevate Ca(2+) levels in sperm. We conclude that EDCs interfere with various sperm functions and, thereby, might impair human fertilization. PMID:24820036

  12. Direct action of endocrine disrupting chemicals on human sperm

    PubMed Central

    Schiffer, Christian; Müller, Astrid; Egeberg, Dorte L; Alvarez, Luis; Brenker, Christoph; Rehfeld, Anders; Frederiksen, Hanne; Wäschle, Benjamin; Kaupp, U Benjamin; Balbach, Melanie; Wachten, Dagmar; Skakkebaek, Niels E; Almstrup, Kristian; Strünker, Timo

    2014-01-01

    Synthetic endocrine disrupting chemicals (EDCs), omnipresent in food, household, and personal care products, have been implicated in adverse trends in human reproduction, including infertility and increasing demand for assisted reproduction. Here, we study the action of 96 ubiquitous EDCs on human sperm. We show that structurally diverse EDCs activate the sperm-specific CatSper channel and, thereby, evoke an intracellular Ca2+ increase, a motility response, and acrosomal exocytosis. Moreover, EDCs desensitize sperm for physiological CatSper ligands and cooperate in low-dose mixtures to elevate Ca2+ levels in sperm. We conclude that EDCs interfere with various sperm functions and, thereby, might impair human fertilization. PMID:24820036

  13. Src Kinase Is the Connecting Player between Protein Kinase A (PKA) Activation and Hyperpolarization through SLO3 Potassium Channel Regulation in Mouse Sperm.

    PubMed

    Stival, Cintia; La Spina, Florenza A; Baró Graf, Carolina; Arcelay, Enid; Arranz, Silvia E; Ferreira, Juan J; Le Grand, Sibylle; Dzikunu, Victor A; Santi, Celia M; Visconti, Pablo E; Buffone, Mariano G; Krapf, Dario

    2015-07-24

    Plasma membrane hyperpolarization is crucial for mammalian sperm to acquire acrosomal responsiveness during capacitation. Among the signaling events leading to mammalian sperm capacitation, the immediate activation of protein kinase A plays a pivotal role, promoting the subsequent stimulation of protein tyrosine phosphorylation that associates with fertilizing capacity. We have shown previously that mice deficient in the tyrosine kinase cSrc are infertile and exhibit improper cauda epididymis development. It is therefore not clear whether lack of sperm functionality is due to problems in epididymal maturation or to the absence of cSrc in sperm. To further address this problem, we investigated the kinetics of cSrc activation using anti-Tyr(P)-416-cSrc antibodies that only recognize active cSrc. Our results provide evidence that cSrc is activated downstream of PKA and that inhibition of its activity blocks the capacitation-induced hyperpolarization of the sperm plasma membrane without blocking the increase in tyrosine phosphorylation that accompanies capacitation. In addition, we show that cSrc inhibition also blocks the agonist-induced acrosome reaction and that this inhibition is overcome by pharmacological hyperpolarization. Considering that capacitation-induced hyperpolarization is mediated by SLO3, we evaluated the action of cSrc inhibitors on the heterologously expressed SLO3 channel. Our results indicate that, similar to SLO1 K(+) channels, cSrc blockers significantly decreased SLO3-mediated currents. Together, these results are consistent with findings showing that hyperpolarization of the sperm plasma membrane is necessary and sufficient to prepare the sperm for the acrosome reaction and suggest that changes in sperm membrane potential are mediated by cSrc activation.

  14. Src Kinase Is the Connecting Player between Protein Kinase A (PKA) Activation and Hyperpolarization through SLO3 Potassium Channel Regulation in Mouse Sperm*

    PubMed Central

    Stival, Cintia; La Spina, Florenza A.; Baró Graf, Carolina; Arcelay, Enid; Arranz, Silvia E.; Ferreira, Juan J.; Le Grand, Sibylle; Dzikunu, Victor A.; Santi, Celia M.; Visconti, Pablo E.; Buffone, Mariano G.; Krapf, Dario

    2015-01-01

    Plasma membrane hyperpolarization is crucial for mammalian sperm to acquire acrosomal responsiveness during capacitation. Among the signaling events leading to mammalian sperm capacitation, the immediate activation of protein kinase A plays a pivotal role, promoting the subsequent stimulation of protein tyrosine phosphorylation that associates with fertilizing capacity. We have shown previously that mice deficient in the tyrosine kinase cSrc are infertile and exhibit improper cauda epididymis development. It is therefore not clear whether lack of sperm functionality is due to problems in epididymal maturation or to the absence of cSrc in sperm. To further address this problem, we investigated the kinetics of cSrc activation using anti-Tyr(P)-416-cSrc antibodies that only recognize active cSrc. Our results provide evidence that cSrc is activated downstream of PKA and that inhibition of its activity blocks the capacitation-induced hyperpolarization of the sperm plasma membrane without blocking the increase in tyrosine phosphorylation that accompanies capacitation. In addition, we show that cSrc inhibition also blocks the agonist-induced acrosome reaction and that this inhibition is overcome by pharmacological hyperpolarization. Considering that capacitation-induced hyperpolarization is mediated by SLO3, we evaluated the action of cSrc inhibitors on the heterologously expressed SLO3 channel. Our results indicate that, similar to SLO1 K+ channels, cSrc blockers significantly decreased SLO3-mediated currents. Together, these results are consistent with findings showing that hyperpolarization of the sperm plasma membrane is necessary and sufficient to prepare the sperm for the acrosome reaction and suggest that changes in sperm membrane potential are mediated by cSrc activation. PMID:26060254

  15. Relationship between conventional sperm parameters and motile sperm organelle morphology examination (MSOME).

    PubMed

    Perdrix, A; Saïdi, R; Ménard, J F; Gruel, E; Milazzo, J P; Macé, B; Rives, N

    2012-08-01

    With the motile sperm organelle morphology examination (MSOME), spermatozoa morphology may be assessed directly on motile spermatozoa at high magnification (up to 6600×). This procedure describes more precisely spermatozoa abnormalities, especially head vacuoles. However, no consensus has been established concerning normal or abnormal MSOME criteria. The aim of our study was to define MSOME vacuole criteria assessed objectively with a digital imaging system software to establish a potential relationship between conventional semen parameters. A total of 440 semen samples were obtained from males consulting in Rouen University Hospital Reproductive Biology Laboratory. Conventional semen analysis (volume, sperm concentration, progressive motility, vitality and morphology) and MSOME assessment {sperm head length, width and area as well as vacuole number, vacuole area and relative vacuole area to sperm head [RVA (%) = [vacuole area (μm(2))/head area (μm(2))] × 100)]} were performed for each semen sample. Among our 440 males, 109 presented normal conventional semen parameters and 331 abnormal ones. Sperm head vacuoles were significantly larger in abnormal semen samples (p < 0.0001). RVA was the most discriminative MSOME criterion between normal and abnormal semen samples according to ROC curves analysis, and was negatively correlated with poor sperm morphology (r = -0.53, p < 0.0001). We concluded to (i) the normal occurrence of vacuoles in sperm head whatever the normality or abnormality of semen parameters, (ii) the discriminative function of the RVA to distinguish semen samples with normal and abnormal parameters, and (iii) the strong correlation between high RVA and poor sperm morphology.

  16. Changes in Sperm Motility and Capacitation Induce Chromosomal Aberration of the Bovine Embryo following Intracytoplasmic Sperm Injection.

    PubMed

    Kato, Yoku; Nagao, Yoshikazu

    2015-01-01

    Intracytoplasmic sperm injection (ICSI) has become the method of choice to treat human male infertility. One of the outstanding problems associated with this technique is our current lack of knowledge concerning the effect of sperm capacitation and motility upon the subsequent development of oocytes following ICSI. In the present study, we first examined the capacitation state of sperm exhibiting normal motility, along with sperm that had been activated, and examined the effect of reactive oxygen species (ROS) produced by these sperm types upon embryogenesis following bovine in vitro fertilization (IVF) and ICSI. Data showed that activated sperm reduced the chromosomal integrity of IVF/ICSI embryos at the blastocyst stage, while capacitated sperm produced ROS in capacitation media. Secondly, we treated sperm with carbonyl cyanide m-chlorophenyl hydrazine (CCCP), a chemical known to uncouple cell respiration within the mitochondria, and investigated the effect of this treatment upon blastocyst formation and chromosomal integrity at the blastocyst stage. Activated sperm in which the mitochondria had been treated with CCCP reduced levels of chromosomal aberration at the blastocyst stage following ICSI, by reducing mitochondrial activity in activated sperm. In conclusion, these findings suggest that capacitated sperm exhibiting activated motility induced chromosomal aberration during development to the blastocyst stage following ICSI. The injection of sperm exhibiting normal motility, or activated sperm in which mitochondrial activity had been reduced, improved the quality of ICSI-derived embryos. Therefore, the selection of sperm exhibiting progressive motility may not always be better for early embryo development and fetal growth following human ICSI, and that the use of a bovine model may contribute to a deeper understanding of sperm selection for human ICSI embryo development.

  17. Influence of Post-Mortem Sperm Recovery Method and Extender on Unstored and Refrigerated Rooster Sperm Variables.

    PubMed

    Villaverde-Morcillo, S; Esteso, M C; Castaño, C; Santiago-Moreno, J

    2016-02-01

    Many post-mortem sperm collection techniques have been described for mammalian species, but their use in birds is scarce. This paper compares the efficacy of two post-mortem sperm retrieval techniques - the flushing and float-out methods - in the collection of rooster sperm, in conjunction with the use of two extenders, i.e., L&R-84 medium and Lake 7.1 medium. To determine whether the protective effects of these extenders against refrigeration are different for post-mortem and ejaculated sperm, pooled ejaculated samples (procured via the massage technique) were also diluted in the above extenders. Post-mortem and ejaculated sperm variables were assessed immediately at room temperature (0 h), and after refrigeration at 5°C for 24 and 48 h. The flushing method retrieved more sperm than the float-out method (596.5 ± 75.4 million sperm vs 341.0 ± 87.6 million sperm; p < 0.05); indeed, the number retrieved by the former method was similar to that obtained by massage-induced ejaculation (630.3 ± 78.2 million sperm). For sperm collected by all methods, the L&R-84 medium provided an advantage in terms of sperm motility variables at 0 h. In the refrigerated sperm samples, however, the Lake 7.1 medium was associated with higher percentages of viable sperm, and had a greater protective effect (p < 0.05) with respect to most motility variables. In conclusion, the flushing method is recommended for collecting sperm from dead birds. If this sperm needs to be refrigerated at 5°C until analysis, Lake 7.1 medium is recommended as an extender. PMID:26602054

  18. Failure of pregnancy after intracytoplasmic sperm injection with decapitated spermatozoa: case report.

    PubMed

    Saïas-Magnan, J; Metzler-Guillemain, C; Mercier, G; Carles-Marcorelles, F; Grillo, J M; Guichaoua, M R

    1999-08-01

    The case of a couple with a history of long standing primary infertility is reported in which the man presented with a decapitated sperm defect. The woman had a normal history and presented with normal clinical characteristics. The couple underwent one unsuccessful conventional in-vitro fertilization (IVF). Subsequently, embryos were obtained and transferred after assisted fertilization attempts: in all, three subzonal inseminations and four intracytoplasmic sperm injections. A total of 49 mature oocytes was injected in both studies, 25 embryos obtained and 20 embryos transferred, three of them after freezing and thawing. Despite the good embryo morphology, implantation was unsuccessful and no pregnancy occurred. The failure of implantation may have resulted from an arrest in early embryonic development related to the sperm anomaly. One hypothesis is that transferred embryos may carry a chromosomal imbalance that prevents them from progressing to the blastocyst stage. Nevertheless, we cannot exclude the possibility that the woman is responsible for the implantation failure. Co-culture associated with a further attempt could provide information regarding the ability of embryos to progress to the blastocyst stage and implant.

  19. Porcine circovirus type 2 detection in in vitro produced porcine blastocysts after virus sperm exposure.

    PubMed

    Galeati, Giovanna; Zannoni, Augusta; Spinaci, Marcella; Bucci, Diego; Ostanello, Fabio; Panarese, Serena; Tamanini, Carlo; Sarli, Giuseppe

    2016-04-01

    This study was aimed at assessing the capability of semen experimentally infected with porcine circovirus type 2 (PCV2) to produce porcine blastocysts PCR positive for PCV2. Embryos were obtained from in vitro maturation (IVM) and in vitro fertilization (IVF) of porcine oocytes or by parthenogenesis. Sperm suspension was exposed to PCV2b and utilized for IVF. PCV2 spiked semen did not reveal any reduction in sperm viability or motility but its ability to produce infected blastocysts was irrelevant as only one out of 15 blastocysts obtained by IVF were PCV2b; however two blastocysts were PCV2a positive. Furthermore, the presence of PCV2 was demonstrated also in embryos obtained by parthenogenesis (one out of 17 was PCV2b and one PCV2a positive). Even if PCV2 firmly attaches to the surface of spermatozoa, experimentally spiked sperm were not effective in infecting oocytes during IVF and in producing PCR positive embryos. The infected blastocysts we obtained derived most probably from infected oocytes recovered at the abattoir. PMID:26434667

  20. Sperm transfer and reproductive biology in species of hermaphroditic bivalves (Galeommatoidea: Montacutidae).

    PubMed

    Fox, Thomas H; Jespersen, Ase; Lützen, Jørgen

    2007-11-01

    The histology of the reproductive organs is studied in the protandric hermaphroditic Tellimya ferruginosa. In NW Europe the species reproduces from May through August. Sperm transfer takes place when mature testis follicles are transplanted to the gills or walls of the mantle cavity in recipient hermaphroditic or female bivalves. Transplantation is accompanied by histological changes and sperm cells are released when transplants perish with age. Details are given on the reproduction in Montacuta percompressa which takes place from March through October in North Carolina, USA. All shelled bivalves are females and it is postulated that spermatogenic bodies attached to gills or other surfaces in the female's mantle cavity and previously considered to be dwarf males arise from transplanted larval gonads. The ultrastructure of the euspermatozoa and/or the anucleate paraspermatozoa is described in T. ferruginosa, T. tenella, and M. percompressa. The sperm of the first two species share a number of significant apomorphies with those of another montacutid, Brachiomya stigmatica. In the simultaneous hermaphroditic M. substriata the nucleate paraspermatozoa associate with the euspermatozoa to form spherical spermatozeugmata that are stored in the testis.

  1. Galactosylceramidase deficiency causes sperm abnormalities in the mouse model of globoid cell leukodystrophy

    SciTech Connect

    Luddi, A.; Strazza, M.; Carbone, M.; Moretti, E.; Costantino-Ceccarini, E. . E-mail: costantino@unisi.it

    2005-03-10

    The classical recessive mouse mutant, 'the twitcher,' is one of the several animal models of the human globoid cell leukodystrophy (Krabbe disease) caused by a deficiency in the gene encoding the lysosomal enzyme galactosylceramidase (GALC). The failure to hydrolyze galactosylceramide (gal-cer) and galactosylsphingosine (psychosine) leads to degeneration of oligodendrocytes and severe demyelination. Substrate for GALC is also the galactosyl-alkyl-acyl-glycerol (GalAAG), precursor of the seminolipid, the most abundant glycolipid in spermatozoa of mammals. In this paper, we report the pathobiology of the testis and sperm in the twitcher mouse and demonstrate the importance of GALC for normal sperm maturation and function. The GALC deficit results in accumulation of GalAAG in the testis of the twitcher mouse. Morphological studies revealed that affected spermatozoa have abnormally swollen acrosomes and angulation of the flagellum mainly at midpiece-principal piece junction. Multiple folding of the principal piece was also observed. Electron microscopy analysis showed that in the twitcher sperm, acrosomal membrane is redundant, detached from the nucleus and folded over. Disorganization and abnormal arrangements of the axoneme components were also detected. These results provide in vivo evidence that GALC plays a critical role in spermiogenesis.

  2. Sperm whale assessment in the Western Ionian Sea using acoustic data from deep sea observatories

    NASA Astrophysics Data System (ADS)

    Caruso, Francesco; Bellia, Giorgio; Beranzoli, Laura; De Domenico, Emilio; Larosa, Giuseppina; Marinaro, Giuditta; Papale, Elena; Pavan, Gianni; Pellegrino, Carmelo; Pulvirenti, Sara; Riccobene, Giorgio; Scandura, Danila; Sciacca, Virginia; Viola, Salvatore

    2015-04-01

    The Italian National Institute of Nuclear Physics (INFN) operates two deep sea infrastructures: Capo Passero, Western Ionian Sea 3,600 meters of depth, and Catania Wester Ionian Sea 2,100 m depth. At the two sites, several research observatories have been run: OnDE, NEMO-SN1, SMO, KM3NeT-Italia most of them jointly operated between INFN and INGV. In all these observatories, passive acoustic sensors (hydrophones) have been installed. Passive Acoustics Monitoring (PAM) is nowadays the main tool of the bioacoustics to study marine mammals. In particular, receiving the sounds emitted by cetaceans from a multi-hydrophones array installed in a cabled seafloor observatory, a research about the ecological dynamics of the species may be performed. Data acquired with the hydrophones installed aboard the OnDE, SMO and KM3NeT-Italia observatories will be reported. Thanks to acquired data, the acoustic presence of the sperm whales was assessed and studied for several years (2005:2013). An "ad hoc" algorithm was also developed to allow the automatic identification of the "clicks" emitted by the sperm whales and measure the size of detected animals. According to the results obtained, the sperm whale population in the area is well-distributed in size, sex and sexual maturity. Although specimens more than 14 meters of length (old males) seem to be absent.

  3. Diagnostic tools in male infertility-the question of sperm dysfunction.

    PubMed

    Barratt, Christopher L R; Mansell, Steven; Beaton, Catherine; Tardif, Steve; Oxenham, Senga K

    2011-01-01

    Sperm dysfunction is the single most common cause of infertility, yet what is remarkable is that, there is no drug a man can take or add to his spermatozoa in vitro to improve fertility. One reason for the lack of progress in this area is that our understanding of the cellular and molecular workings of the mature spermatazoon is limited. However, over the last few years there has been considerable progress in our knowledge base and in addressing new methods to diagnose sperm dysfunction. We review the current state of the field and provide insights for further development. We conclude that: (i) there is little to be gained from more studies identifying/categorizing various populations of men using a basic semen assessment, where an effort is required in making sure the analysis is performed in an appropriate high quality way; (ii) technological development is likely to bring the reality of sperm function testing closer to implementation into the clinical pathways. In doing this, these assays must be robust, cheap (or more appropriately termed cost effective), easy to use and clinically useful; and (iii) clinical necessity, e.g., the need to identify the highest quality spermatozoon for injection is driving basic research forward. This is an exciting time to be an andrologist and, likely, a fruitful one.

  4. Sperm storage in the female reproductive tract in birds.

    PubMed

    Sasanami, Tomohiro; Matsuzaki, Mei; Mizushima, Shusei; Hiyama, Gen

    2013-01-01

    The ability to store sperm in the female genital tract is frequently observed in vertebrates as well as in invertebrates. Because of the presence of a system that maintains the ejaculated sperm alive in the female reproductive tract in a variety of animals, this strategy appears to be advantageous for animal reproduction. Although the occurrence and physiological reasons for sperm storage have been reported extensively in many species, the mechanism of sperm storage in the female reproductive tract has been poorly understood until recently. In avian species, the specialized simple tubular invaginations referred to as sperm storage tubules (SSTs) are found in the oviduct as a sperm storage organ. In this review, we summarize the current understanding of the mechanism of sperm uptake into the SSTs, maintenance within it, and controlled release of the sperm from the SSTs. Since sperm storage in avian species occurs at high body temperatures (i.e., 41 C), elucidation of the mechanism for sperm storage may lead to the development of new strategies for sperm preservation at ambient temperatures, and these could be used in a myriad of applications in the field of reproduction.

  5. Sperm Storage in the Female Reproductive Tract in Birds

    PubMed Central

    SASANAMI, Tomohiro; MATSUZAKI, Mei; MIZUSHIMA, Shusei; HIYAMA, Gen

    2013-01-01

    Abstract The ability to store sperm in the female genital tract is frequently observed in vertebrates as well as in invertebrates. Because of the presence of a system that maintains the ejaculated sperm alive in the female reproductive tract in a variety of animals, this strategy appears to be advantageous for animal reproduction. Although the occurrence and physiological reasons for sperm storage have been reported extensively in many species, the mechanism of sperm storage in the female reproductive tract has been poorly understood until recently. In avian species, the specialized simple tubular invaginations referred to as sperm storage tubules (SSTs) are found in the oviduct as a sperm storage organ. In this review, we summarize the current understanding of the mechanism of sperm uptake into the SSTs, maintenance within it, and controlled release of the sperm from the SSTs. Since sperm storage in avian species occurs at high body temperatures (i.e., 41 C), elucidation of the mechanism for sperm storage may lead to the development of new strategies for sperm preservation at ambient temperatures, and these could be used in a myriad of applications in the field of reproduction. PMID:23965601

  6. Sodium affects the sperm motility in the European eel.

    PubMed

    Vílchez, M Carmen; Morini, Marina; Peñaranda, David S; Gallego, Víctor; Asturiano, Juan F; Pérez, Luz

    2016-08-01

    The role of seminal plasma sodium and activation media sodium on sperm motility was examined by selectively removing the element from these two media, in European eel sperm. Sperm size (sperm head area) was also measured using an ASMA (Automated Sperm Morphometry Analyses) system, in the different conditions. Intracellular sodium [Na(+)]i was quantitatively analyzed by first time in the spermatozoa from a marine fish species. Measurement of [Na(+)]i was done before and after motility activation, by Flow Cytometry, using CoroNa Green AM as a dye. Sperm motility activation induced an increase in [Na(+)]i, from 96.72mM in quiescent stage to 152.21mM post-activation in seawater. A significant decrease in sperm head area was observed post-activation in seawater. There was a notable reduction in sperm motility when sodium was removed from the seminal plasma, but not when it was removed from the activation media. Sodium removal was also linked to a significant reduction in sperm head area in comparison to the controls. Our results indicate that the presence of the ion Na(+) in the seminal plasma (or in the extender medium) is necessary for the preservation of sperm motility in European eel, probably because it plays a role in maintaining an appropriate sperm cell volume in the quiescent stage of the spermatozoa. PMID:27085371

  7. Sperm parameters: paradigmatic index of good health and longevity.

    PubMed

    Omu, Alexander E

    2013-01-01

    Since the discovery of spermatozoon by Anton van Leeuwenhoek in 1677, there has been an ever increasing understanding of its role in reproduction. Many factors adversely affect sperm quality, including varicocele, accessory gland infection, immunological factors, congenital abnormalities, and iatrogenic systemic and endocrine causes, such as diabetes mellitus, obesity, metabolic syndrome, and smoking. The mechanisms responsible for the association between poor sperm parameters and ill health may include oxidative stress, low-grade inflammation, low testosterone, and low sex-hormone-binding globulin. Oxidative stress in the testicular microenvironment may result in decreased spermatogenesis and sperm DNA damage, loss of sperm motility, and abnormal sperm morphology. Low testosterone caused by advanced age, visceral obesity, and inflammation is associated with the development of cardiovascular disease. Hence, semen analysis has an important role in the routine evaluation of idiopathic male infertility, usually manifested as low sperm counts, impaired sperm motility, or absence of sperm, and remains the most common single diagnostic tool. Several studies have shown an inverse relationship between semen quality and medical disorders. This review elucidates the effect of medical disorders and social habits on sperm quality, the mechanisms that are involved in the impairment of sperm quality, and whether or not sperm quality can be used as an index of good health and longevity in a man.

  8. Sperm carriers in Silurian sea scorpions.

    PubMed

    Kamenz, Carsten; Staude, Andreas; Dunlop, Jason A

    2011-10-01

    Invasion of the land by arachnids required adaptations of numerous organs, such as gills evolving into lungs, as well as mechanisms facilitating sperm transfer in a terrestrial environment. Many modern arachnids use spermatophores for this purpose, i.e. sperm transmitters detached from the body. Exceptionally preserved Silurian (423 Ma) fossils of Eurypterus tetragonophthalmus Fischer, 1839 (Chelicerata: Eurypterida) preserve so-called 'horn organs' which we here demonstrate as being equivalent to the spermatophore-producing parts of the genital tract in certain modern arachnids. This clarifies a long-running debate about sexing eurypterids based on the shape of the median abdominal (or genital) appendage. To our knowledge this is also the oldest direct evidence for spermatophore-mediated sperm transfer in the fossil record and suggests that eurypterids had evolved mating techniques using spermatophores as early as the Silurian, a valuable prerequisite for life on land. Spermatophores are absent in sea spiders (Pycnogonida) and horseshoe crabs (Xiphosura); thus the shared presence of sclerotized sperm-transfer devices in eurypterids and arachnids is a novel character, newly elucidated here, which offers explicit support for (Eurypterida + Arachnida). For this clade the name Sclerophorata n. nov. is proposed. Arachnida can be further defined by fusion of the originally paired genital opening. PMID:21892606

  9. Controlled freezing studies on boar sperm cryopreservation.

    PubMed

    Medrano, A; Holt, W V; Watson, P F

    2009-08-01

    Boar spermatozoa from different males were frozen at a number of cooling rates using a controlled-rate freezing machine designed to minimise thermal variables involved in the cooling process, to see whether inter-boar sperm cryosurvival may be improved by changing cooling rate. Four cooling rates in the range 3 degrees C min(-1) to 24 degrees C min(-1) from +5 degrees C to -5 degrees C and five cooling rates in the range 5 degrees C min(-1) to 80 degrees C min(-1) from -5 degrees C to -80 degrees C were tested. Motile spermatozoa were assessed by CASA, plasma membrane integrity by fluorescent probes (SYBR14/propidium iodide) and flow cytometry, and acrosome membrane integrity by lectins (PSA-rhodamine) and fluorescent microscopy. Cooling rate affected sperm cryosurvival from different boars in different ways; that is, spermatozoa from some individuals were less susceptible than those from others. For some individuals, sperm cryosurvival was poor regardless of cooling rate, but for others it was better with faster rates. This confirms cooling rate effects on sperm cryosurvival depend on inter-individual boar differences more than on the cooling process itself. PMID:19601937

  10. The monopulsed nature of sperm whale clicks

    NASA Astrophysics Data System (ADS)

    Møhl, Bertel; Wahlberg, Magnus; Madsen, Peter T.; Heerfordt, Anders; Lund, Anders

    2003-08-01

    Traditionally, sperm whale clicks have been described as multipulsed, long duration, nondirectional signals of moderate intensity and with a spectrum peaking below 10 kHz. Such properties are counterindicative of a sonar function, and quite different from the properties of dolphin sonar clicks. Here, data are presented suggesting that the traditional view of sperm whale clicks is incomplete and derived from off-axis recordings of a highly directional source. A limited number of assumed on-axis clicks were recorded and found to be essentially monopulsed clicks, with durations of 100 μs, with a composite directionality index of 27 dB, with source levels up to 236 dB re: 1 μPa (rms), and with centroid frequencies of 15 kHz. Such clicks meet the requirements for long-range biosonar purposes. Data were obtained with a large-aperture, GPS-synchronized array in July 2000 in the Bleik Canyon off Vestera˚len, Norway (69°28' N, 15°40' E). A total of 14 h of sound recordings was collected from five to ten independent, simultaneously operating recording units. The sound levels measured make sperm whale clicks by far the loudest of sounds recorded from any biological source. On-axis click properties support previous work proposing the nose of sperm whales to operate as a generator of sound.

  11. Sperm competition and the evolution of spermatogenesis.

    PubMed

    Ramm, Steven A; Schärer, Lukas; Ehmcke, Jens; Wistuba, Joachim

    2014-12-01

    Spermatogenesis is a long and complex process that, despite the shared overall goal of producing the male gamete, displays striking amounts of interspecific diversity. In this review, we argue that sperm competition has been an important selection pressure acting on multiple aspects of spermatogenesis, causing variation in the number and morphology of sperm produced, and in the molecular and cellular processes by which this happens. We begin by reviewing the basic biology of spermatogenesis in some of the main animal model systems to illustrate this diversity, and then ask to what extent this variation arises from the evolutionary forces acting on spermatogenesis, most notably sperm competition. We explore five specific aspects of spermatogenesis from an evolutionary perspective, namely: (i) interspecific diversity in the number and morphology of sperm produced; (ii) the testicular organizations and stem cell systems used to produce them; (iii) the large number and high evolutionary rate of genes underpinning spermatogenesis; (iv) the repression of transcription during spermiogenesis and its link to the potential for haploid selection; and (v) the phenomenon of selection acting at the level of the germline. Overall we conclude that adopting an evolutionary perspective can shed light on many otherwise opaque features of spermatogenesis, and help to explain the diversity of ways in which males of different species perform this fundamentally important process. PMID:25323971

  12. Effect of Astaxanthin on Human Sperm Capacitation

    PubMed Central

    Donà, Gabriella; Kožuh, Ivana; Brunati, Anna Maria; Andrisani, Alessandra; Ambrosini, Guido; Bonanni, Guglielmo; Ragazzi, Eugenio; Armanini, Decio; Clari, Giulio; Bordin, Luciana

    2013-01-01

    In order to be able to fertilize oocytes, human sperm must undergo a series of morphological and structural alterations, known as capacitation. It has been shown that the production of endogenous sperm reactive oxygen species (ROS) plays a key role in causing cells to undergo a massive acrosome reaction (AR). Astaxanthin (Asta), a photo-protective red pigment belonging to the carotenoid family, is recognized as having anti-oxidant, anti-cancer, anti-diabetic and anti-inflammatory properties and is present in many dietary supplements. This study evaluates the effect of Asta in a capacitating buffer which induces low ROS production and low percentages of acrosome-reacted cells (ARC). Sperm cells were incubated in the presence or absence of increasing concentrations of Asta or diamide (Diam) and analyzed for their ROS production, Tyr-phosphorylation (Tyr-P) pattern and percentages of ARC and non-viable cells (NVC). Results show that Asta ameliorated both sperm head Tyr-P and ARC values without affecting the ROS generation curve, whereas Diam succeeded in enhancing the Tyr-P level but only of the flagellum without increasing ARC values. It is suggested that Asta can be inserted in the membrane and therefore create capacitation-like membrane alteration which allow Tyr-P of the head. Once this has occurred, AR can take place and involves a higher numbers of cells. PMID:23736766

  13. Effect of astaxanthin on human sperm capacitation.

    PubMed

    Donà, Gabriella; Kožuh, Ivana; Brunati, Anna Maria; Andrisani, Alessandra; Ambrosini, Guido; Bonanni, Guglielmo; Ragazzi, Eugenio; Armanini, Decio; Clari, Giulio; Bordin, Luciana

    2013-06-01

    In order to be able to fertilize oocytes, human sperm must undergo a series of morphological and structural alterations, known as capacitation. It has been shown that the production of endogenous sperm reactive oxygen species (ROS) plays a key role in causing cells to undergo a massive acrosome reaction (AR). Astaxanthin (Asta), a photo-protective red pigment belonging to the carotenoid family, is recognized as having anti-oxidant, anti-cancer, anti-diabetic and anti-inflammatory properties and is present in many dietary supplements. This study evaluates the effect of Asta in a capacitating buffer which induces low ROS production and low percentages of acrosome-reacted cells (ARC). Sperm cells were incubated in the presence or absence of increasing concentrations of Asta or diamide (Diam) and analyzed for their ROS production, Tyr-phosphorylation (Tyr-P) pattern and percentages of ARC and non-viable cells (NVC). Results show that Asta ameliorated both sperm head Tyr-P and ARC values without affecting the ROS generation curve, whereas Diam succeeded in enhancing the Tyr-P level but only of the flagellum without increasing ARC values. It is suggested that Asta can be inserted in the membrane and therefore create capacitation-like membrane alteration which allow Tyr-P of the head. Once this has occurred, AR can take place and involves a higher numbers of cells. PMID:23736766

  14. Cryopreservation of mutton snapper ( Lutjanus analis) sperm.

    PubMed

    Sanches, Eduardo G; Oliveira, Idili R; Serralheiro, Pedro C Da Silva; Cerqueira, Vinicius R

    2013-09-01

    This study aimed to develop a protocol of semen cryopreservation of the mutton snapper Lutjanus analis. The interaction between three extenders ( pH 6.1; 7.8 and 8.2) , two concentrations of dimethyl sulfoxide ( DMSO, 5 and 10%) and three cooling rates ( -90; -60 and -30°C.min-1) on the sperm motility rate and motility time were analyzed by a factorial experiment. A sample of 30 fishes ( 1,261 ± 449 g) collected in the nature was kept in floating net cages. The semen was frozen by using cryogenic straws, in nitrogen vapour and transferred, later, to liquid nitrogen. Fertilization test was accomplished to evaluate the viability of the cryopreserved sperm. The highest sperm motility rate and motility time ( P < 0.05) was achieved by combining extender C ( pH 8.2) with DMSO ( 10%) and cooling rate of -60°C.min-1 ( P < 0.05) . The use of cryopreserved sperm presented fertilization rates higher than 59% validating the present protocol for mutton snapper.

  15. Sperm carriers in Silurian sea scorpions

    NASA Astrophysics Data System (ADS)

    Kamenz, Carsten; Staude, Andreas; Dunlop, Jason A.

    2011-10-01

    Invasion of the land by arachnids required adaptations of numerous organs, such as gills evolving into lungs, as well as mechanisms facilitating sperm transfer in a terrestrial environment. Many modern arachnids use spermatophores for this purpose, i.e. sperm transmitters detached from the body. Exceptionally preserved Silurian (423 Ma) fossils of Eurypterus tetragonophthalmus Fischer, 1839 (Chelicerata: Eurypterida) preserve so-called `horn organs' which we here demonstrate as being equivalent to the spermatophore-producing parts of the genital tract in certain modern arachnids. This clarifies a long-running debate about sexing eurypterids based on the shape of the median abdominal (or genital) appendage. To our knowledge this is also the oldest direct evidence for spermatophore-mediated sperm transfer in the fossil record and suggests that eurypterids had evolved mating techniques using spermatophores as early as the Silurian, a valuable prerequisite for life on land. Spermatophores are absent in sea spiders (Pycnogonida) and horseshoe crabs (Xiphosura); thus the shared presence of sclerotized sperm-transfer devices in eurypterids and arachnids is a novel character, newly elucidated here, which offers explicit support for (Eurypterida + Arachnida). For this clade the name Sclerophorata n. nov. is proposed. Arachnida can be further defined by fusion of the originally paired genital opening.

  16. Expression and Purification of Sperm Whale Myoglobin

    ERIC Educational Resources Information Center

    Miller, Stephen; Indivero, Virginia; Burkhard, Caroline

    2010-01-01

    We present a multiweek laboratory exercise that exposes students to the fundamental techniques of bacterial expression and protein purification through the preparation of sperm whale myoglobin. Myoglobin, a robust oxygen-binding protein, contains a single heme that gives the protein a reddish color, making it an ideal subject for the teaching…

  17. The monopulsed nature of sperm whale clicks.

    PubMed

    Møhl, Bertel; Wahlberg, Magnus; Madsen, Peter T; Heerfordt, Anders; Lund, Anders

    2003-08-01

    Traditionally, sperm whale clicks have been described as multipulsed, long duration, nondirectional signals of moderate intensity and with a spectrum peaking below 10 kHz. Such properties are counterindicative of a sonar function, and quite different from the properties of dolphin sonar clicks. Here, data are presented suggesting that the traditional view of sperm whale clicks is incomplete and derived from off-axis recordings of a highly directional source. A limited number of assumed on-axis clicks were recorded and found to be essentially monopulsed clicks, with durations of 100 micros, with a composite directionality index of 27 dB, with source levels up to 236 dB re: 1 microPa (rms), and with centroid frequencies of 15 kHz. Such clicks meet the requirements for long-range biosonar purposes. Data were obtained with a large-aperture, GPS-synchronized array in July 2000 in the Bleik Canyon off Vesterålen, Norway (69 degrees 28' N, 15 degrees 40' E). A total of 14 h of sound recordings was collected from five to ten independent, simultaneously operating recording units. The sound levels measured make sperm whale clicks by far the loudest of sounds recorded from any biological source. On-axis click properties support previous work proposing the nose of sperm whales to operate as a generator of sound.

  18. Comparative analysis of mammalian sperm motility.

    PubMed

    Phillips, D M

    1972-05-01

    Spermatozoa of several mammalian species were studied by means of high-speed cinematography and electron microscopy. Three types of motile patterns were observed in mouse spermatozoa. The first type involved an asymmetrical beat which seemed to propel the sperm in circular paths. The second type involved rotation of the sperm and appeared to allow them to maintain straight paths. In the third type of pattern, the sperm appeared to move by crawling on surfaces in a snakelike manner. Spermatozoa of rabbit and Chinese hamster also had an asymmetrical beat which sometimes caused them to swim in circles. In spite of the asymmetry of the beat, these spermatozoa were also able to swim in straight paths by rotating around a central axis as they swam. Spermatozoa of some species appeared very flexible; their flagella formed arcs with a very small radius of curvature as they beat. Spermatozoa of other species appeared very stiff, and their flagella formed arcs with a very large radius of curvature. The stiffness of the spermatozoan appeared to correlate positively with the cross-sectional area of the dense fibers. This suggests that the dense fibers may be stiff elastic elements. Opossum sperm become paired as they pass through the epididymis. Pairs of opossum spermatozoa beat in a coordinated, alternating manner.

  19. Chemical induction of sperm abnormalities in mice.

    PubMed Central

    Wyrobek, A J; Bruce, W R

    1975-01-01

    The sperm of (C57BL X C3H)F1 mice were examined 1, 4, and 10 weeks after a subacute treatment with one of 25 chemicals at two or more dose levels. The fraction of sperm that were abnormal in shape was elevated above control values of 1.2-3.4% for methyl methanesulfonate, ethyl methanesulfonate, griseofulvin, benzo[a]pyrene, METEPA [tris(2-methyl-l-aziridinyl)phosphine oxide], THIO-TEPA [tris(l-aziridinyl)phosphine sulfide], mitomycin C, myleran, vinblastine sulphate, hydroxyurea, 3-methylcholanthrene, colchicine, actinomycin D, imuran, cyclophosphamide, 5-iododeoxyuridine, dichlorvos, aminopterin, and trimethylphosphate. Dimethylnitrosamine, urethane, DDT [1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane], 1,1-dimethylhydrazine, caffeine, and calcium cyclamate did not induce elevated levels of sperm ab