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Kate A Redgrove, Ilana R Bernstein, Victoria J Pye, Bettina P Mihalas, Jessie M Sutherland, Brett Nixon, Adam McCluskey, Phillip J Robinson, Janet E Holt, Eileen A McLaughlin
The dynamin family of proteins play important regulatory roles in membrane remodelling and endocytosis, especially within brain and neuronal tissues. In the context of reproduction, dynamin 1 (DNM1) and dynamin 2 (DNM2) have recently been shown to act as key mediators of sperm acrosome formation and function. However, little is known about the roles that these proteins play in the developing testicular germ cells. In this study, we employed a DNM2 germ cell-specific knockout model to investigate the role of DNM2 in spermatogenesis...
October 11, 2016: Scientific Reports
Lizette du Plessis, John T Soley
Head shaping in mammalian sperm is regulated by a number of factors including acrosome formation, nuclear condensation and the action of the microtubular manchette. A role has also been suggested for the attendant Sertoli cells and the perinuclear theca (PT). In comparison, relatively little information is available on this topic in birds and the presence of a PT per se has not been described in this vertebrate order. This study revealed that a similar combination of factors contributed to head shaping in the ostrich, emu and rhea, although the Sertoli cells seem to play a limited role in ratites...
September 28, 2016: Tissue & Cell
E Malama, Y Zeron, F Janett, M Siuda, Z Roth, H Bollwein
Seasonal fluctuations of climate are considered a major factor affecting spermatogenesis and semen quality in the bovine. Our study aimed to investigate the effect of season on functional parameters of frozen-thawed bovine semen using computer-assisted sperm analysis (CASA) and flow cytometry. For this purpose, 86 ejaculates were collected from five mature Holstein-Friesian bulls kept under subtropical conditions during summer (August to September; n = 43) and winter (December to January; n = 43) months. Semen was diluted with a Tris-egg yolk-based extender and frozen at -196 °C...
August 25, 2016: Theriogenology
Maíra M Brito, Cristina F Lúcio, Daniel S R Angrimani, João Diego A Losano, Andressa Dalmazzo, Marcílio Nichi, Camila I Vannucchi
In addition to the existence of several cryopreservation protocols, no systematic research has been carried out in order to confirm the suitable protocol for canine sperm. This study aims to assess the effect of adding 5% glycerol during cryopreservation at 37°C (one-step) and 5°C (two-steps), in addition of testing two thawing protocols (37°C for 30 seconds, and 70°C for 8 seconds). We used 12 sperm samples divided into four experimental groups: Single-Step - Slow Thawing Group; Two-Step - Slow Thawing Group; Single-Step - Fast Thawing Group; and Two-Step - Fast Thawing Group...
August 10, 2016: Animal Biotechnology
Lis C Puga Molina, Nicolás A Pinto, Paulina Torres Rodríguez, Ana Romarowski, Alberto Vicens Sanchez, Pablo E Visconti, Alberto Darszon, Claudia L Treviño, Mariano G Buffone
Mammalian sperm require to spend a limited period of time in the female reproductive tract to become competent to fertilize in a process called capacitation. It is well established that HCO3(-) is essential for capacitation because it activates the atypical soluble adenylate cyclase ADCY10 leading to cAMP production, and promotes alkalinization of cytoplasm and membrane hyperpolarization. However, how HCO3(-) is transported into the sperm is not well understood. There is evidence that CFTR activity is involved in the human sperm capacitation but how this channel is integrated in the complex signaling cascades associated with this process remains largely unknown...
October 7, 2016: Journal of Cellular Physiology
S A H Shah, S M H Andrabi, I Z Qureshi
Effects of curcumin as antioxidant in extender were evaluated on freezability of buffalo spermatozoa. Semen from each of the five bulls (n = 3 replicates, six ejaculates/bull, a total of 30 ejaculates) was diluted in Tris-citric acid extender containing curcumin (0.5, 1.0, 1.5 or 2.0 mM) or control. At pre-freezing and post-thawing, total antioxidant contents (μM/L) and lipid peroxidation levels (μM/ml) were higher (p < .05) and lower (p < .05) respectively, with 1.5 and 2.0 mM compared to 0...
October 6, 2016: Andrologia
Beatriz Fernandez-Fuertes, Fernando Narciandi, Cliona O'Farrelly, Alan K Kelly, Sean Fair, Kieran G Meade, Patrick Lonergan
Bovine beta-defensin 126 (BBD126) exhibits preferential expression for the cauda epididymis of males, where it is absorbed onto the tail and post acrosomal region of sperm. The aim of this study was to examine the role of BBD126 in bull sperm function. Fresh and frozen-thawed semen were incubated in the presence of different capacitating agents, as well as with phosphatidylinositol-specific phospholipase C. These treatments, which have been successful in releasing beta-defensin 126 from macaque sperm, proved to be ineffective in bull sperm...
October 5, 2016: Biology of Reproduction
W L Flowers, F Deller, K R Stewart
The objective of this study was to evaluate relationships between common semen quality estimates including sperm motility, sperm morphology, spontaneous capacitation status and seminal plasma proteins and boar fertility using heterospermic inseminations and subsequent paternity testing. All boars (n=12) used in the study had excellent semen quality (≥70% normal sperm) that resulted in average farrowing rates and litter sizes of 88.9±0.7% and 11.7±0.1 pigs, respectively. Their ejaculates were combined to make heterospermic insemination doses in such a way that each boar was tested against all of his contemporaries...
September 29, 2016: Animal Reproduction Science
L Barón, K Fara, H Zapata-Carmona, L Zuñiga, M Kong, J Signorelli, E S Díaz, P Morales
In human spermatozoa, protein kinases have a role in the acrosome reaction (AR) induced by a variety of stimuli. However, there is disagreement or a lack of information regarding the role of protein kinases and phosphatases in the progesterone (P)-induced increase in intracellular calcium concentration ([Ca(2+) ]i ). In addition, there are no studies regarding the role of Ser/Thr and Tyr phosphatases and there are contradictory results regarding the role of Tyr kinases in the P-induced acrosome reaction. Here, we performed a simultaneous evaluation of the involvement of protein kinases and phosphatases in the P-induced acrosome reaction and in the P-induced calcium influx...
October 1, 2016: Andrology
Ida Marie Boisen, Lasse Bøllehuus Hansen, Li Juel Mortensen, Beate Lanske, Anders Juul, Martin Blomberg Jensen
Vitamin D is a versatile signaling molecule with an established role in the regulation of calcium homeostasis and bone health. In recent years the spectrum of vitamin D target organs has expanded and a reproductive role is supported by the presence of the vitamin D receptor (VDR) and the vitamin D metabolizing enzymes in the gonads, reproductive tract, and human spermatozoa. Interestingly, expression levels of VDR and the vitamin D inactivating enzyme CYP24A1 in human spermatozoa serve as positive predictive markers of semen quality and are higher expressed in spermatozoa from normal than infertile men...
September 28, 2016: Journal of Steroid Biochemistry and Molecular Biology
A T M Cunha, J O Carvalho, N R Kussano, C F Martins, G B Mourão, M A N Dode
In this study we examined quality, longevity and ability of epididymal sperm (EP) to bind to oviduct explants (OE) after cooling and cryopreservation. Ejaculated (EJ) and EP sperm from seven bulls were evaluated before, during and after cryopreservation for total (TM), progressive motility (PM), sperm morphology, plasma membrane integrity (PMI) and acrosome integrity (ACI). For longevity, cryopreserved EP, EJ and a third group of cells in which EP spermatozoa were incubated with seminal plasm (SP) for 10 min after thawing (EPP group), were compared, and the groups were analyzed at 0, 3, 6, and 24 h for all parameters...
September 28, 2016: Cryobiology
Shi-Kai Jin, Wan-Xi Yang
In mammals, fertilization occurs via a comprehensive progression of events. Freshly ejaculated sperm have yet to acquire progressive motility or fertilization ability. They must first undergo a series of biochemical and physiological changes, collectively known as capacitation. Capacitation is a significant prerequisite to fertilization. During the process of capacitation, changes in membrane properties, intracellular ion concentration and the activities of enzymes, together with other protein modifications, induce multiple signaling events and pathways in defined media in vitro or in the female reproductive tract in vivo...
September 27, 2016: Oncotarget
C C Arraztoa, M H Miragaya, M G Chaves, V L Trasorras, M C Gambarotta, C H Péndola, D M Neild
The aims of this study were to evaluate porcine sperm vitrification in cryoloops, with and without two different cryoprotectants and assess two warming procedures. Extended (n = 3; r = 4) and raw (n = 5; r = 2) semen was diluted in media without and with cryoprotectants (4% dimethylformamide and 4% glycerol) to a final concentration of 20 × 10(6) spermatozoa ml(-1) and vitrified using the cryoloops method. Two warming procedures were evaluated: rapid method (30 s at 37°C) and an ultra-rapid method (7 s at 75°C, followed by 30 s at 37°C)...
September 29, 2016: Andrologia
Jana Jankovicova, Michaela Frolikova, Natasa Sebkova, Michal Simon, Petra Cupperova, Denisa Lipcseyova, Katarina Michalkova, Lubica Horovska, Radislav Sedlacek, Pavel Stopka, Jana Antalikova, Katerina Dvorakova-Hortova
Sperm-egg interaction and fusion represents a key moment of fertilization and it would not happen in mammals without the interaction of the tetraspanin superfamily members including protein CD81. A detailed immunohistochemical localization of CD81 was monitored on bovine oocytes of different maturation stages, as well as during early embryogenesis. There was also a CD81characterization on bovine and mouse sperm carried out. On bovine eggs, CD81 was detected on the plasma membrane of the germinal vesicle, metaphase I and metaphase II oocytes...
September 27, 2016: Reproduction: the Official Journal of the Society for the Study of Fertility
S A Holden, B Fernandez-Fuertes, C Murphy, H Whelan, A O'Gorman, L Brennan, S T Butler, P Lonergan, S Fair
The hypothesis of this study was that different in vitro parameters are required to predict the in vivo fertility of non-sorted (NS) and sex-sorted (SS) semen. Thus, the aim was to correlate in vitro bull sperm functional parameters (experiment 1) and seminal plasma composition (experiment 2) with pregnancy rates using 2 cohorts of bulls (NS and SS). Experiment 1: ejaculates from each bull (n = 3 ejaculates per bull; n = 6 bulls for both NS and SS) were assessed for motility, thermal stress tolerance and morphology using microscopy, and viability, osmotic resistance, mitochondrial membrane potential, and acrosome integrity using flow cytometry...
September 3, 2016: Theriogenology
A Franchi, M Cubilla, H A Guidobaldi, A A Bravo, L C Giojalas
STUDY QUESTION: Does the rapid transit through the uterine environment modulate the sperm physiological state? SUMMARY ANSWER: The uterosome-like vesicles (ULV) secreted by endometrial epithelial cells (EEC) in vitro are able to fuse with human spermatozoa, prompting their fertilising capacity. WHAT IS KNOWN ALREADY: Early studies suggest that sperm capacitation begins in the uterus and ends in the oviduct, and that a synergistic effect of both female organs may accelerate this process...
September 27, 2016: Molecular Human Reproduction
Hernán Cucho, Virgilio Alarcón, César Ordóñez, Enrique Ampuero, Aydee Meza, Carles Soler
The Andean puma (Puma concolor) has not been widely studied, particularly in reference to its semen characteristics. The aim of the present study was to define the morphometry of puma sperm heads and classify their subpopulations by cluster analysis. Samples were recovered postmortem from two epididymides from one animal and prepared for morphological observation after staining with the Hemacolor kit. Morphometric data were obtained from 581 spermatozoa using a CASA-Morph system, rendering 13 morphometric parameters...
September 27, 2016: Asian Journal of Andrology
Violeta Calle-Guisado, Ana Hurtado de Llera, David Martin-Hidalgo, Jose Mijares, Maria C Gil, Ignacio S Alvarez, Maria J Bragado, Luis J Garcia-Marin
AMP-activated kinase (AMPK), a protein that regulates energy balance and metabolism, has recently been identified in boar spermatozoa where regulates key functional sperm processes essential for fertilization. This work's aims are AMPK identification, intracellular localization, and their role in human spermatozoa function. Semen was obtained from healthy human donors. Sperm AMPK and phospho-Thr172-AMPK were analyzed by Western blotting and indirect immunofluorescence. High- and low-quality sperm populations were separated by a 40%-80% density gradient...
September 27, 2016: Asian Journal of Andrology
W Niżański, A Partyka, S Prochowska
Conventional microscopic semen analysis does not provide precise information on the fertilizing potential of a male. The traditional basis for semen evaluation is that male fertility is dependent on production of a "proper" concentration/number of motile, morphologically normal spermatozoa in excess to achieve conception. Many independent studies, especially in human medicine, have demonstrated that the absolute number of spermatozoa does not accurately determine fertility, but their functional competence. Many functional tests of spermatozoa are developed over the last decades...
September 2016: Reproduction in Domestic Animals, Zuchthygiene
Michaela Frolikova, Natasa Sebkova, Lukas Ded, Katerina Dvorakova-Hortova
The acrosome reaction (AR) is a process of membrane fusion and lytic enzyme release, which enables sperm to penetrate the egg surroundings. It is widely recognized that specific sperm proteins form an active network prior to fertilization, and their dynamic relocation is crucial for the sperm-egg fusion. The unique presence of the membrane cofactor protein CD46 in the sperm acrosomal membrane was shown, however, its behaviour and connection with other sperm proteins has not been explored further. Using super resolution microscopy, we demonstrated a dynamic CD46 reorganisation over the sperm head during the AR, and its interaction with transmembrane protein integrins, which was confirmed by proximity ligation assay...
September 26, 2016: Scientific Reports
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