Showing papers on "Sperm motility published in 2006"
TL;DR: The roles of these ions on sperm motility in Salmonidae, Cyprinidae, Acipenseridae and marine fishes are reviewed and their relationship with seminal plasma composition is reviewed.
527 citations
TL;DR: There are multiple spermatogenic targets for genomically defective sperm with substantially variable susceptibilities to age, and it is predicted that as healthy males age, they have decreased pregnancy success with trends beginning in their early reproductive years, increased risk for producing offspring with achondroplasia mutations, and risk of fathering offspring with Apert syndrome.
Abstract: This study compares the relative effects of advancing male age on multiple genomic defects in human sperm [DNA fragmentation index (DFI), chromatin integrity, gene mutations, and numerical chromosomal abnormalities], characterizes the relationships among these defects and with semen quality, and estimates the incidence of susceptible individuals for a well characterized nonclinical nonsmoking group of 97 men (22-80 years). Adjusting for confounders, we found major associations between age and the frequencies of sperm with DFI and fibroblast growth factor receptor 3 gene (FGFR3) mutations associated with achondroplasia (P < 0.01) with no evidence for age thresholds. However, we found no associations between age and the frequencies of sperm with immature chromatin, aneuploidies/diploidies, FGFR2 mutations (Apert syndrome), or sex ratio in this cohort. There were also no consistent correlations among genomic and semen-quality endpoints, except between DFI and sperm motility (r = -0.65, P < 0.001). These findings suggest there are multiple spermatogenic targets for genomically defective sperm with substantially variable susceptibilities to age. Our findings predict that as healthy males age, they have decreased pregnancy success with trends beginning in their early reproductive years, increased risk for producing offspring with achondroplasia mutations, and risk of fathering offspring with Apert syndrome that may vary across cohorts, but with no increased risk for fathering aneuploid offspring (Down, Klinefelter, Turner, triple X, and XYY syndromes) or triploid embryos. Our findings also suggest that the burden of genomic damage in sperm cannot be inferred from semen quality, and that a small fraction of men are at increased risk for transmitting multiple genetic and chromosomal defects.
354 citations
TL;DR: For the first time, incorporation of labeled amino acids into polypeptides during sperm capacitation is demonstrated, which was completely inhibited by mitochondrial translation inhibitors but not by the cytoplasmic translation inhibitor.
Abstract: It is widely accepted that spermatozoa are translationally silent. The present study demonstrates, for the first time, incorporation of labeled amino acids into polypeptides during sperm capacitation, which was completely inhibited by mitochondrial translation inhibitors but not by the cytoplasmic translation inhibitor. Unlike 80S cytoplasmic ribosomes, 55S mitochondrial ribosomes were present in polysomal fractions, indicating that these ribosomes are actively involved in protein translation in spermatozoa. Inhibition of protein translation significantly reduced sperm motility, capacitation and in vitro fertilization rate. Thus, contrary to the accepted dogma, nuclear genes are expressed as proteins in sperm during their residence in the female reproductive tract until fertilization.
322 citations
TL;DR: A range of in vitro tests have been developed to monitor various aspects of sperm function including their potential for movement, cervical mucus penetration, capacitation, zona recognition, the acrosome reaction and sperm-oocyte fusion and such functional assays have been found to predict the fertilizing capacity of human spermatozoa in vitro and in vivo with some accuracy.
Abstract: Traditionally, the diagnosis of male infertility has depended upon a descriptive evaluation of human semen with emphasis on the number of spermatozoa that are present in the ejaculate, their motility and their morphology. The fundamental tenet underlying this approach is that male fertility can be defined by reference to a threshold concentration of motile, morphologically normal spermatozoa that must be exceeded in order to achieve conception. Many independent studies have demonstrated that this fundamental concept is flawed and, in reality, it is not so much the absolute number of spermatozoa that determines fertility, but their functional competence. In the light of this conclusion, a range of in vitro tests have been developed to monitor various aspects of sperm function including their potential for movement, cervical mucus penetration, capacitation, zona recognition, the acrosome reaction and sperm-oocyte fusion. Such functional assays have been found to predict the fertilizing capacity of human spermatozoa in vitro and in vivo with some accuracy. Recent developments in this field include the introduction of tests to assess the degree to which human spermatozoa have suffered oxidative stress as well as the integrity of their nuclear and mitochondrial DNA. Such assessments not only yield information on the fertilizing capacity of human spermatozoa but also their ability to support normal embryonic development.
286 citations
TL;DR: Flow cytometry revealed that catalase, but not superoxide dismutase, was capable of attenuating ROS-induced inhibition of motility and both viable fresh and frozen-thawed boar sperm were quite susceptible to external sources of hydrogen peroxide.
Abstract: The use of frozen semen in the swine industry is limited by problems with viability and fertility compared with liquid semen. Part of the reduction in sperm motility and fertility associated with cryopreservation may be due to oxidative damage from excessive or inappropriate formation of reactive oxygen species (ROS). Chemiluminescence measurements of ROS are not possible in live cells and are problematic because of poor specificity. An alternative approach, flow cytometry, was developed to identify viable boar sperm containing ROS utilizing the dyes hydroethidine and 2', 7'-dichlorodihydrofluorescein diacetate as oxidizable substrates and impermeant DNA dyes to exclude dead sperm. The percentage of sperm with high mitochondrial transmembrane potential was determined by flow cytometry using the mitochondrial probe 5, 5', 6, 6'-tetrachloro-1, 1', 3, 3'-tetraethylbenzimidazolylcarbocyanine iodide with propidium iodide staining to exclude nonviable cells. Sperm were incubated with and without ROS generators and free radical scavengers. Basal ROS formation was low (less than 4%) and did not differ (P = 0.26) between viable fresh and frozen-thawed boar sperm. In addition, fresh and frozen-thawed viable sperm were equally susceptible (P = 0.20) to intracellular formation of ROS produced by xanthine/xanthine oxidase (94.4 and 87.9% of sperm, respectively). Menadione increased (P < 0.05) ROS formation, decreased (P < 0.05) JC-1-aggregate fluorescence intensity, and decreased (P < 0.05) motion variables by 25 to 60%. The mechanism of inhibition of motility by ROS formation may be related to a decrease in mitochondrial charge potential below a critical threshold. Catalase and superoxide dismutase treatment in the presence of xanthine/xanthine oxidase indicated that hydrogen peroxide was the primary intracellular ROS measured. Further, catalase, but not superoxide dismutase, was capable of attenuating ROS-induced inhibition of motility. Whereas basal intracellular hydrogen peroxide formation was low in viable fresh and frozen-thawed boar sperm, both were quite susceptible to external sources of hydrogen peroxide.
285 citations
TL;DR: The results show that sperm DNA damage does not impair fertilization of the oocyte or completion of the first 2-3 cleavages, but blocks blastocyst formation by inducing apoptosis.
Abstract: The main goal of this study was to investigate whether and at what level damage of paternal DNA influences fertilization of oocytes and early embryonic development. We hypothesized that posttesticular sperm DNA damage will only marginally affect sperm physiology due to the lack of gene expression, but that it will affect embryo development at the stage that embryo genome (including the paternal damaged DNA) expression is initiated. To test this, we artificially induced sperm DNA damage by irradiation with x- or gamma rays (doses of 0-300 Gy). Remarkably, sperm cells survived the irradiation quite well and, when compared with nonirradiated cells, sperm motility and integrity of plasma membrane, acrosome, and mitochondria were not altered by this irradiation treatment. In contrast, a highly significant logarithmic relation between irradiation dose and induced DNA damage to sperm cells was found by both terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL) and the acridin orange assay. Despite the DNA damage, irradiated sperm cells did not show any sign of apoptosis (nuclear fragmentation, depolarization of inner mitochondrial membranes, or phospholipid scrambling) and were normally capable of fertilizing oocytes, as there was no reduction in cleavage rates when compared with nonirradiated sperm samples up to irradiation doses of less than 10 Gy. Further embryonic development was completely blocked as the blastocyst rates at days 7 and 9 dropped from 28% (nonirradiated sperm) to less than 3% by greater than 2.5-Gy-irradiated sperm. This block in embryonic development was accompanied with the initiation of apoptosis after the second or third cleavage. Specific signs of apoptosis, such as nuclear fragmentation and aberrations in spindle formation, were observed in all embryos resulting from in vitro fertilization with irradiated sperm (irradiation doses >1.25 Gy). The results show that sperm DNA damage does not impair fertilization of the oocyte or completion of the first 2-3 cleavages, but blocks blastocyst formation by inducing apoptosis. Embryos produced by assisted reproductive techniques (ART) could have incorporated aberrant paternal DNA (frequently detected in sperm of sub/infertile males). Analogously, in the present work, we discuss the possibility of following embryo development of oocytes fertilized by ART through the blastocyst stage before embryo transfer into the uterus in order to reduce risks of reproductive failure.
266 citations
TL;DR: The present review is designed to bring the clinician up to date with the most current understanding of the mechanisms that regulate sperm motility and to raise questions about how aberrations in these mechanisms could be the underlying causes of this pathology.
Abstract: Because it is generally accepted that a high percentage of poorly motile or immotile sperm will adversely affect male fertility, analysis of sperm motility is a central part of the evaluation of male fertility In spite of its importance to fertility, poor sperm motility remains only a description of a pathology whose underlying cause is typically poorly understood The present review is designed to bring the clinician up to date with the most current understanding of the mechanisms that regulate sperm motility and to raise questions about how aberrations in these mechanisms could be the underlying causes of this pathology
259 citations
TL;DR: Sperm motility and concentration provide more accurate information than morphology (WHO and Tygerberg's criteria) during infertility evaluation, and redefining the reference values for concentration and morphology may significantly increase the importance of routine semen analysis.
259 citations
TL;DR: In most species, it is unlikely that local glycolysis is the only way that ATP can be supplied to the distal flagellum, and evidence that gluconeogenesis is a possible explanation, is weak.
Abstract: It is doubtful that diffusion can deliver sufficient ATP from the mitochondria to sustain activity at the distal end of the sperm flagellum. Glycolytic enzymes bound to the fibrous sheath could provide energy along the flagellum at the point it is required. An obligatory role for glycolysis is supported by the lack of progressive motility in sperm from mice where the gene for sperm-specific glyceraldehyde-3-phosphate dehydrogenase (GAPDHs) had been ‘knocked out’. Here, I review some evidence against this idea. First, pure diffusion from the mitochondrion is likely to be adequate in species with smaller sperm, and it is possible that rapid ATP delivery required in larger sperm could be achieved by an adenylate kinase shuttle. Second, experience with -chlorohydrin demonstrates that sperm can remain motile with normal ATP concentrations despite inhibition of GAPDHs; adverse effects only occur if glucose is added and high levels of glycolytic intermediates accumulate. These observations undermine the GAPDHs knockout mouse as evidence for an essential role of local glycolysis. Third, sperm from many species can remain motile for long periods in sugarfree media and excepting dog sperm, evidence that gluconeogenesis is a possible explanation, is weak. In most species, it is unlikely that local glycolysis is the only way that ATP can be supplied to the distal flagellum.
253 citations
TL;DR: The results from this experimental study suggest that the lycopene have a possible protective effect against cisplatin-induced spermiotoxicity, effect of giving Lycopene after cisplinatin being superior to the giving it before cisplillin, although the mechanism is not clear.
249 citations
TL;DR: The data suggest that EMR emitted by cellular phone influences human sperm motility and long-term EMR exposure may lead to behavioral or structural changes of the male germ cell.
TL;DR: The results show that there is little within-male and considerable between-male variation in sperm dimensions, and the hydrodynamic shape of the head and the forces generated by the relative size of the rest of the flagellum seem to be the key determinants of sperm swimming velocity.
Abstract: Spermatozoa vary enormously in their form and dimensions, both between and within species, yet how this variation translates into fertilizing efficiency is not known. Sperm swimming velocity is a key determinant of male fertilization success, but previous efforts to identity which sperm phenotypic traits are associated with swimming velocity have been unsuccessful. Here, we examine the relationship between the size of several sperm components and sperm swimming velocity in natural populations of red deer (Cervus elaphus hispanicus) where selective pressures to enhance male reproductive success are expected to be strong. Our results show that there is little within-male and considerable between-male variation in sperm dimensions. Spermatozoa with longer midpieces swim more slowly, a finding which does not support the hypothesis that the size of the midpiece determines the amount of energy which is translated into swimming speed. In contrast, spermatozoa with elongated heads, and those in which the relative length of the rest of the flagellum is longer, swim faster. Thus, the hydrodynamic shape of the head and the forces generated by the relative size of the rest of the flagellum seem to be the key determinants of sperm swimming velocity.
TL;DR: FSH, LH, inhibin B, testosterone and free T4 levels are associated with human semen parameters, and FSH and LH were inversely associated with sperm concentration, motility, and morphology.
Abstract: Participation rates in epidemiologic studies on semen quality are generally very low, raising concerns as to the potential for selection bias. Since hormones both initiate and maintain spermatogenesis, they may serve as surrogates of semen quality in epidemiologic studies. For this reason, in the present study, we explored the influence and predictive ability of reproductive and thyroid hormones on semen quality among men who were partners in an infertile couple. Between 1999 and 2003, 388 men were recruited from Massachusetts General Hospital Andrology Laboratory for clinical evaluation of fertility status. Fresh semen samples were assessed for quality (concentration, motility and morphology) and the serum levels of hormones, including follicle-stimulating hormone (FSH), luteinizing hormone (LH), inhibin B, sex hormone-binding globulin (SHBG), testosterone, free androgen index, free T4, total T3, and thyroid-stimulating hormone (TSH), were measured. Multiple logistic regression revealed increased odds for below-reference sperm concentration and morphology in men with increased FSH, and decreased odds for below-reference sperm concentration and motility in men with increased inhibin B. When FSH and inhibin B were divided into quintiles, the relationships with sperm concentration showed evidence of a threshold value. However, the ability of specific FSH (10 IU/L) and/or inhibin B (80 pg/mL) cutoff values to predict semen quality was lower than in previous reports. In multiple linear regression analysis, FSH and LH were inversely associated with sperm concentration, motility, and morphology. Inhibin B and free T4 were positively associated with sperm concentration, while there was a suggestive positive association between testosterone and sperm motility. In conclusion, we have found that FSH, LH, inhibin B, testosterone and free T4 levels are associated with human semen parameters. Additional consideration should be given to the utility of serum hormone levels as a surrogate for semen quality in epidemiologic studies in which the collection of semen is difficult due to logistical and/or volunteer rate constraints.
TL;DR: In vivo study using mito-mice directly demonstrates that normal mitochondrial respiration is required for mammalian spermatogenesis, and its defects resulting from accumulated mutant mtDNAs cause male infertility.
Abstract: Approximately 15% of human couples are affected by infertility, and about half of these cases of infertility can be attributed to men, through low sperm motility (asthenozoospermia) or/and numbers (oligospermia). Because mitochondrial genome (mtDNA) mutations are identified in patients with fertility problems, there is a possibility that mitochondrial respiration defects contribute to male infertility. To address this possibility, we used a transmitochondrial mouse model (mito-mice) carrying wild-type mtDNA and mutant mtDNA with a pathogenic 4,696-bp deletion (ΔmtDNA). Here we show that mitochondrial respiration defects caused by the accumulation of ΔmtDNA induced oligospermia and asthenozoospermia in the mito-mice. Most sperm from the infertile mito-mice had abnormalities in the middle piece and nucleus. Testes of the infertile mito-mice showed meiotic arrest at the zygotene stage as well as enhanced apoptosis. Thus, our in vivo study using mito-mice directly demonstrates that normal mitochondrial respiration is required for mammalian spermatogenesis, and its defects resulting from accumulated mutant mtDNAs cause male infertility.
TL;DR: Results indicate that BSPs play a crucial role in fertilization by maintaining sperm motility during storage by increasing binding of epididymal sperm to epithelium and as effective as PDC-109 in competitively inhibiting binding of ejaculated sperm.
Abstract: On ejaculation, sperm become coated with proteins secreted by the male accessory sex glands. In the bull, these proteins consist predominantly of the bovine seminal plasma family of proteins (BSPs): PDC-109 (BSP-A1/-A2), BSP-A3, and BSP-30-kDa. PDC-109 plays a role in forming an oviductal sperm reservoir by enabling sperm to bind to oviductal epithelium. Because PDC-109 has high sequence identity with the other BSPs, we tested BSP-A3 and BSP-30-kDa for the capacity to bind sperm to oviductal epithelium. BSP-A3 and BSP-30-kDa each increased binding of epididymal sperm to epithelium and were as effective as PDC-109 in competitively inhibiting binding of ejaculated sperm. Because binding extends the motile life of sperm, BSPs were tested for the ability to maintain sperm motility. BSP-treated epididymal sperm incubated with plasma membrane vesicles from bovine oviductal epithelium maintained progressive motility longer than untreated sperm. To our knowledge, this is the first report of this protective effect of BSPs. Similarities in function among the BSPs were reflected in their three-dimensional structure, whereas surface maps of electrostatic potential indicated differences in binding affinities and kinetics. Such differences may provide sperm with greater adaptability to variations among females. Altogether, these results indicate that BSPs play a crucial role in fertilization by maintaining sperm motility during storage.
TL;DR: Microinjection of vacuolated sperm appears to reduce the pregnancy rate and appears to be associated with early abortion in IVF-ICSI.
Abstract: Background To verify whether or not microinjection of sperm with a normal nuclear shape but large vacuoles affects IVF-ICSI pregnancy outcome. Methods A comparative study testing IVF outcome parameters of IVF-ICSI, based on morphological selection of spermatozoa with normal nuclei against those based on microinjection of sperm with a normal nuclear shape but large vacuoles. An experimental group, including 28 IVF-ICSI cycles, where only embryos obtained from microinjection of spermatozoa with a normal nuclear shape but large vacuoles were transferred, was matched with a control group, including 28 IVF-ICSI cycles, where only embryos obtained from microinjection of spermatozoa with a strictly defined morphologically normal nuclear shape and content were transferred. The main outcome was IVF-ICSI pregnancy rate. Results The experimental group exhibited a significantly lower pregnancy rate per cycle and significantly higher abortion rate per pregnancy compared to the control group (18 versus 50%, and 80 versus 7%, respectively, P=0.01). Conclusion Microinjection of vacuolated sperm appears to reduce the pregnancy rate and appears to be associated with early abortion.
TL;DR: Progesterone indeed chemotactically guides mammalian spermatozoa at very low hormone concentrations, and the cumulus oophorus could be a potential place for sperm chemotaxis mediated by progesterone in vivo.
TL;DR: It is suggested that cigarette smoking may have deleterious effects on sperm nuclear quality and that sperm DNA fragmentation can therefore be considered as an independent parameter with diagnostic, prognostic, and strategic value in the treatment of infertility.
TL;DR: A role for the fibrous sheath as a scaffold for anchoring multiple glycolytic enzymes along the length of the flagellum to provide a localized source of ATP that is essential for sperm motility is supported.
Abstract: The fibrous sheath is a cytoskeletal structure located in the principal piece of mammalian sperm flagella Previous studies showed that glyceraldehyde 3-phosphate dehydrogenase, spermatogenic (GAPDHS), a germ cell-specific glycolytic isozyme that is required for sperm motility, is tightly bound to the fibrous sheath To determine if other glycolytic enzymes are also bound to this cytoskeletal structure, we isolated highly purified fibrous sheath preparations from mouse epididymal sperm using a sequential extraction procedure The isolated fibrous sheaths retain typical ultrastructural features and exhibit little contamination by axonemal or outer dense fiber proteins in Western blot analyses Proteomic analysis using peptide-mass fingerprinting and MS/MS peptide fragment ion matching identified GAPDHS and two additional glycolytic enzyme subunits, the A isoform of aldolase 1 (ALDOA) and lactate dehydrogenase A (LDHA), in isolated fibrous sheaths The presence of glycolytic enzymes in the fibrous sheath was also examined by Western blotting In addition to GAPDHS, ALDOA, and LDHA, this method determined that pyruvate kinase is also tightly bound to the fibrous sheath These data support a role for the fibrous sheath as a scaffold for anchoring multiple glycolytic enzymes along the length of the flagellum to provide a localized source of ATP that is essential for sperm motility
TL;DR: It is suggested that decreased DHA and PUFA, and increased w6/w3 in spermatozoa may be related to infertility in oligo- and/or asthenozoospermic men.
Abstract: Introduction The lipid composition of spermatozoa plays an important role for successful fertilization. Patients and methods In the present study, we analyzed the fatty acid (FA) composition of spermatozoa of normozoospermic, asthenozoospermic, oligozoospermic and oligoasthenozoospermic men. Results Spermatozoa from asthenozoospermic ( P P P P P P P P P P P Saturated fatty acids (SFA) were significantly higher in asthenozoospermic ( P P r = 0.53 ), sperm concentration ( r = 0.36 ) and normal sperm morphology ( r = 0.30 ). In addition, there were significant correlations between PUFA with sperm motility ( r = 0.50 ), sperm concentration ( r = 0.35 ), and normal sperm morphology ( r = 0.28 ), and between w6/w3 with sperm motility ( r = - 0.47 ), sperm concentration ( r = - 0.27 ), and normal sperm morphology( r = - 0.24 ). Discussion These suggest that decreased DHA and PUFA, and increased w6/w3 in spermatozoa may be related to infertility in oligo- and/or asthenozoospermic men.
TL;DR: The presence of excess unsaturated fatty acids in defective human spermatozoa may precipitate the oxidative stress encountered in male infertility.
Abstract: Context: Defective sperm function is the largest defined cause of human infertility; however, the etiology of this condition is poorly understood. Although oxidative stress is acknowledged as a key contributor to this pathology, there are also data indicating that defective human spermatozoa contain abnormally high amounts of cis-unsaturated fatty acids. This study investigated whether a causative relationship exists between these two attributes of impaired semen quality. Objective: The objective of this study was to determine whether polyunsaturated fatty acids can induce oxidative stress in human spermatozoa. Method: Dihydroethidium and SYTOX Green were used in conjunction with flow cytometry and HPLC to investigate reactive oxygen species (ROS) generation by human spermatozoa after fatty acid exposure. Results: Arachidonic acid (AA) induced a time- and dose-dependent increase in ROS generation by human spermatozoa that led to the promotion of peroxidative damage and a loss of sperm motility. This effec...
TL;DR: It is reported that males, in a species with status-dependent shifts in reproductive tactics, have evolved rapid tactic specific adjustments of sperm production and sperm velocity corresponding to what could be predicted from their reproductive roles.
Abstract: Sperm competition models predict that males typically mating in disfavoured roles should be selected to compensate for their disadvantage by investing more into sperm. We studied the effect of rapid changes in social status on ejaculate investments during experimental trials with an externally fertilizing teleost—the Arctic charr (Salvelinus alpinus). We document that males becoming dominant produce less sperm with lower velocity, but have higher sex steroid concentrations than subordinate males. These differences in sperm characteristics seem mainly to result from a decreased investment in sperm among fish that become dominant compared to pre-trial levels. Moreover, these adjustments of sperm production and sperm velocity seem not to be traded against sperm longevity. Our results support theoretical models of sperm competition, as males forced to mate in disfavoured roles seem to invest more into ejaculate quality than males in favoured roles. Additionally, we are the first to report that males, in a species with status-dependent shifts in reproductive tactics, have evolved rapid tactic specific adjustments of sperm production and sperm velocity corresponding to what could be predicted from their reproductive roles.
TL;DR: Both H.sabdariffa and Z.officinale treatment increased the activities of testicular antioxidant enzymes and restored sperm motility of cisplatin-treated rats, suggesting the protective effects of tested plants are suggested to be mediated by their potent antioxidant activities.
Abstract: Aim: To evaluate the protective effects of Hibiscus sabdariffa (Roselle) and Zingiber officinale (Ginger) against cisplatin-induced reproductive toxicity in rats and to study the mechanisms underlying these effects. Methods: Ethanol extracts of H. sabdariffa or Z. officinale [1 g/(kg·day)] were given p.o. to male albino rats for 26 days, which began 21 days before a single cisplatin i.p. injection (10 mg/kg body weight). Results: Extracts of H. sabdariffa and Z. officinale reduced the extent of cisplatin-induced sperm abnormality and enhanced sperm motility. Both extracts restored the control level of malondialdehyde (MDA) (lipid peroxidation marker) in the cisplatin-treated testis. The cisplatin injection induced decline in the levels of superoxide dismutase (SOD), reduced glutathione (GSH) and catalase (CAT) were significantly reversed to control levels in groups where cisplatin was preceded by the administration of either H. sabdariffa or Z. officinale. Conclusion: Both H. sabdariffa and Z. officinale treatment increased the activities of testicular antioxidant enzymes and restored sperm motility of cisplatin-treated rats. The protective effects of tested plants are, therefore, suggested to be mediated by their potent antioxidant activities. (Asian J Androl 2006 Sep; 8: 607–612)
TL;DR: The aim of the present experiment was to study the effect of fish oil and Vitamin E rich diets on semen production, sperm functions and composition in broiler breeders, and significant interactions between the two treatments were found for some parameters.
TL;DR: Boar is the most important factor explaining the variability among ejaculates in sperm cryosurvival, with most (14 of the 15 boars in Exp. 3) showing consistent (P > 0.05) sperm cryopreservation over time.
Abstract: 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 70% of total variance observed in postthaw sperm quality variables among ejaculates was explained by boar. This indicates that boar is the most important (P 0.05) sperm cryosurvival over time.
TL;DR: These data indicate large within- and between-subject variation in sperm parameters, especially sperm count, in both patients and healthy donors, and further substantiate the need for measurement of multiple ejaculates before characterizing a man as normal or infertile.
TL;DR: It is shown that polyunsaturated fatty acids (PUFAs), the precursors of eicosanoid signalling molecules, function in oocytes to control directional sperm motility within the uterus.
Abstract: A fundamental question in animal development is how motile cells find their correct target destinations. During mating in the nematode Caenorhabditis elegans, males inject sperm through the hermaphrodite vulva into the uterus. Amoeboid sperm crawl around fertilized eggs to the spermatheca – a convoluted tube where fertilization occurs1,2. Here, we show that polyunsaturated fatty acids (PUFAs), the precursors of eicosanoid signalling molecules, function in oocytes to control directional sperm motility within the uterus. PUFAs are transported from the intestine, the site of fat metabolism, to the oocytes yolk, which is a lipoprotein complex. Loss of the RME-2 low-density lipoprotein (LDL) receptor, which mediates yolk endocytosis3 and fatty acid transport into oocytes, causes severe defects in sperm targeting. We used an RNAi screen to identify lipid regulators required for directional sperm motility. Our results support the hypothesis that PUFAs function in oocytes as precursors of signals that control sperm recruitment to the spermatheca. A common property of PUFAs in mammals and C. elegans is that these fats control local recruitment of motile cells to their target tissues.
TL;DR: It is shown that CP‐treatment impaired markedly testicular function and combined treatment with melatonin prevented much of the toxicity in rats, and treatment with CP plus melatonin provided significant amelioration of oxidative stress parameters.
Abstract: In this study, we investigated the effect of melatonin on cisplatin-induced spermiotoxicity using quantitative, biochemical and histopathological approaches. Cisplatin (CP, 7 mg/kg) and melatonin (10 mg/kg) were intraperitoneally injected. The rats were decapitated on 5th (short-term group) or 50th day (long-term group) after CP injection. Traits of reproductive organs, sperm characteristics, testicular histological findings, and the lipid peroxidation in the testicular tissue were determined. Melatonin mitigated CP-induced reductions in testes, epididymis and accessory gland weights in rats decapitated on day 5. Both short- and long-term CP treatment decreased sperm concentration, sperm motility and increased abnormal sperm rates compared with the control. But the reduction of sperm concentration in long-term CP treatment was insignificant. Although treatment with melatonin provided moderately normalization with respect to sperm concentration in short-term treatment group, melatonin caused a marked normalization of sperm motility in both CP + melatonin groups. Both groups treated with the melatonin showed decreases in abnormal sperm rates compared with alone CP. While testicular malondialdehyde levels were elevated after CP treatment, glutathione peroxidase activity decreased significantly in both groups. Glutathione levels reduced after long-term treatment, but not in short-term group by CP administration. Treatment with CP plus melatonin provided significant amelioration of oxidative stress parameters. Histopathological findings of testes in both short- and long-term treatment groups paralleled the biochemical and spermatogenic results. This study clearly indicates that CP-treatment impaired markedly testicular function and combined treatment with melatonin prevented much of the toxicity in rats.
TL;DR: Seminal MDA concentrations are negatively correlated with sperm concentration and motility, which might provide a simple and useful tool in predicting sperm parameters, and GPx activity is non-significantly correlated with the seminal quality.
Abstract: Objectives: Reactive oxygen species (ROS) induced lipid peroxidation is associated with sperm function. Malondialdehyde (MDA) concentration and glutathione peroxidase (GPx) activity represent the lipid peroxidation and spermicidal antioxidant, respectively. We aimed to evaluate the relationship of MDA and GPx levels with sperm parameters.
Patients and methods: Specimens were divided into two groups: group 1. normospermia (n=20); group 2. oligoasthenospermia (n=31). Seminal MDA concentration was measured by thiobarbituric acid reaction method. Seminal GPx activity was measured by oxidation of reduced nicotinamide-adenine dinucleotide. Seminal MDA levels and GPx activities in both groups were compared.
Results: MDA concentrations in both groups were significantly different (1.52 ± 0.75 vs. 2.25 ± 0.88 nM, p = 0.0021). GPx activities in both groups were non-significantly different (0.48 ± 0.11 vs. 0.47 ± 0.12 U/ml). MDA levels were negatively correlated with the sperm motility (MDA = -0.014 x motility + 2.62, p =0.017) and concentration (MDA = -0.0045 x concentration + 2.23, p = 0.0166). GPx activities were positively but non-significantly correlated with the sperm concentration and sperm motility.
Conclusions: Seminal MDA concentrations are negatively correlated with sperm concentration and motility, which might provide a simple and useful tool in predicting sperm parameters. GPx activity is non-significantly correlated with the seminal quality. Roles of seminal MDA upon spermatogenesis merits further surveys.
TL;DR: Age, non-inflammatory functional alterations in post-testicular organs, infective agents, alterations in gamete genome, mitochondrial alterations, environmental pollutants and "subtle" hormonal alterations are all considered possible causes of iOAT.
Abstract: Idiopathic oligoasthenoteratozoospermia (iOAT) affects approximately 30% of all infertile men. This mini-review discussed recent data in this field. Age, non-inflammatory functional alterations in post-testicular organs, infective agents (Chlamydia trachomatis, herpes virus and adeno-associated viruses), alterations in gamete genome, mitochondrial alterations, environmental pollutants and "subtle" hormonal alterations are all considered possible causes of iOAT. Increase of reactive oxygen species in tubules and in seminal plasma and of apoptosis are reputed to affect sperm concentration, motility and morphology. iOAT is commonly diagnosed by exclusion, nevertheless spectral traces of the main testicular artery may be used as a diagnostic tool for iOAT. The following can be considered therapies for iOAT: 1) tamoxifen citrate (20 mg/d) + testosterone undecanoate (120 mg/d) (pregnancy rate per couple/month [prcm]: 3.8%); 2) folic acid (66 mg/d) + zinc sulfate (5 mg/d); 3) L-carnitine (2 g/d) alone or in combination with acetyl-L-carnitine (1 g/d) (prcm: 2.3%); and 4) both carnitines = one 30 mg cinnoxicam suppository every 4 days (prcm: 8.5%). Alpha-blocking drugs improved sperm concentration but not morphology, motility or pregnancy rate. Tranilast (300 mg/d) increased sperm parameters and pregnancy rates in an initial uncontrolled study. Its efficacy on sperm concentration (but not on sperm motility, morphology or prcm) was confirmed in subsequent published reports. The efficacy of tamoxifen + testosterone undecanoate, tamoxifen alone, and recombinant follicle-stimulating hormone is still a matter for discussion.