Showing papers on "Sperm motility published in 2001"
TL;DR: Threshold values for sperm concentration, motility, and morphology can be used to classify men as subfertile, of indeterminate fertility, or fertile and none of the measures are diagnostic of infertility.
Abstract: Background Although semen analysis is routinely used to evaluate the male partner in infertile couples, sperm measurements that discriminate between fertile and infertile men are not well defined. Methods We evaluated two semen specimens from each of the male partners in 765 infertile couples and 696 fertile couples at nine sites. The female partners in the infertile couples had normal results on fertility evaluation. The sperm concentration and motility were determined at the sites; semen smears were stained at the sites and shipped to a central laboratory for an assessment of morphologic features of sperm with the use of strict criteria. We used classification-and-regression-tree analysis to estimate threshold values for subfertility and fertility with respect to the sperm concentration, motility, and morphology. We also used an analysis of receiver-operating-characteristic curves to assess the relative value of these sperm measurements in discriminating between fertile and infertile men. Results The su...
1,129 citations
TL;DR: A putative sperm cation channel, CatSper, whose amino-acid sequence most closely resembles a single, six-transmembrane-spanning repeat of the voltage-dependent Ca2+-channel four-repeat structure is described, located specifically in the principal piece of the sperm tail.
Abstract: Calcium and cyclic nucleotides have crucial roles in mammalian fertilization, but the molecules comprising the Ca2+-permeation pathway in sperm motility are poorly understood. Here we describe a putative sperm cation channel, CatSper, whose amino-acid sequence most closely resembles a single, six-transmembrane-spanning repeat of the voltage-dependent Ca2+-channel four-repeat structure. CatSper is located specifically in the principal piece of the sperm tail. Targeted disruption of the gene results in male sterility in otherwise normal mice. Sperm motility is decreased markedly in CatSper-/- mice, and CatSper-/- sperm are unable to fertilize intact eggs. In addition, the cyclic-AMP-induced Ca2+ influx is abolished in the sperm of mutant mice. CatSper is thus vital to cAMP-mediated Ca2+ influx in sperm, sperm motility and fertilization. CatSper represents an excellent target for non-hormonal contraceptives for both men and women.
826 citations
TL;DR: The weight of the evidence suggests that increased male age is associated with a decline in semen volume, sperm motility, and sperm morphology but not with sperm concentration.
644 citations
TL;DR: The strong correlation between sperm DD and DF, and the higher levels of sperm DNA damage in infertile compared with fertile men, indicate that male infertility is associated with poor sperm DNA integrity.
422 citations
TL;DR: The high levels of ROS production and DNA damage observed in immature spermatozoa may be indicative of derangements in the regulation of spermiogenesis, which is implicated in the pathogenesis of male infertility.
Abstract: BACKGROUND: Reactive oxygen species (ROS)-induced damage of membrane phospholipids and DNA in human spermatozoa has been implicated in the pathogenesis of male infertility. In this study, variations in ROS production, DNA structure (as measured by the sperm chromatin structure assay) and lipid composition, were studied in human spermatozoa at different stages of maturation. METHODS: Sperm subsets were isolated by discontinuous density gradient centrifugation of semen samples obtained from healthy donors and from infertility patients. RESULTS: DNA damage and ROS production were highest in immature spermatozoa with cytoplasmic retention and abnormal head morphology, and lowest in mature spermatozoa. Docosahexaenoic acid and sterol content were highest in immature germ cells and immature spermatozoa, and lowest in mature spermatozoa. The relative proportion of ROS-producing immature spermatozoa in the sample was directly correlated with DNA damage in mature spermatozoa, and inversely correlated with the recovery of motile spermatozoa. There was no correlation between DNA damage and sperm morphology in mature spermatozoa. CONCLUSIONS: The high levels of ROS production and DNA damage observed in immature spermatozoa may be indicative of derangements in the regulation of spermiogenesis. DNA damage in mature spermatozoa may be the result of oxidative damage by ROS-producing immature spermatozoa during sperm migration from the seminiferous tubules to the epididymis.
373 citations
TL;DR: The results demonstrated that deleterious effects sperm motility after cryopreservation in EYTG can be counteracted by adding various thiols at mM concentration, and indicated in the extender that the glutathione redox-cycle was deficient.
330 citations
TL;DR: There is significant cell-to-cell variation in ROS production in subsets of spermatozoa at different stages of maturation and that oxidative damage of mature spermatozosa by ROS-producing immature spermatoza during sperm migration from the seminiferous tubules to the epididymis may be an important cause of male infertility.
Abstract: BACKGROUND: Reactive oxygen species (ROS)-mediated damage to human spermatozoa has been implicated in the pathogenesis of male infertility. Although ROS production by human spermatozoa has been extensively studied, the cell-to-cell variation in ROS production by spermatozoa at different stages of maturation has never been investigated. METHODS: In this study, we determined ROS production by subsets of human spermatozoa at different stages of maturation isolated by density gradient centrifugation of ejaculated spermatozoa obtained from healthy donors and from patients attending a clinic for infertility screening. RESULTS: Four different fractions were obtained. ROS production was highest in immature spermatozoa with abnormal head morphology and cytoplasmic retention and lowest in mature spermatozoa and immature germ cells (P < 0.01). ROS production was highest in immature spermatozoa from males with abnormal semen parameters compared with donors (P < 0.0001) or patients with normal semen parameters (P 0.015). ROS production by immature spermatozoa was inversely correlated with the recovery of motile, mature spermatozoa in the high density fraction 4 (P 0.01). CONCLUSIONS: The results of this study indicate that there is significant cell-to-cell variation in ROS production in subsets of spermatozoa at different stages of maturation and that oxidative damage of mature spermatozoa by ROS-producing immature spermatozoa during sperm migration from the seminiferous tubules to the epididymis may be an important cause of male infertility.
326 citations
TL;DR: A voltage-gated ion channel (CatSper2) is reported that is expressed in male germ cells but not in other cells, and it is possible that two independent α subunits, different from other known voltage- gated channels, regulate sperm motility.
Abstract: Calcium ions play a primary role in the regulation of sperm cell behavior. We report finding a voltage-gated ion channel (CatSper2) that is expressed in male germ cells but not in other cells. The putative channel contains 6 transmembrane segments, making it more similar to the voltage-gated potassium channels, but the ion selectivity pore domain sequence resembles that of a Cav channel. The mRNA is expressed during the meiotic or postmeiotic stages of spermatogenesis, and the protein is localized to the sperm flagellum, suggesting a role in the regulation of sperm motility. The mRNA for the channel is present in mouse, rat, and human sperm cells, and the gene is found on chromosome 2 E5–F1 in the mouse and 15q13 in the human. Recently, another voltage-gated channel (CatSper) that has features similar to the one reported here was discovered. It also is expressed within the flagellum and is required for normal fertility of mice. However, expression of CatSper2 alone or coexpression with CatSper in cultured cells, or attempts to coimmunoprecipitate the two proteins from germ cells failed to demonstrate that these two unique but similar α-like subunits form either a homo- or heterotetramer. It is possible, therefore, that two independent α subunits, different from other known voltage-gated channels, regulate sperm motility.
307 citations
TL;DR: It was found that merocyanine 540 detects capacitation-related changes much earlier than CTC does, and that flow cytometry for evaluation of capacitation and AR was a quicker and more accurate technique than fluorescence microscopy.
Abstract: The primary aim of this study was to establish a flow cytometric technique for determining the capacitation status of stallion spermatozoa. To this end, a flow cytometric technique that demonstrates changes in plasma membrane fluidity; namely, merocyanine 540 staining, was compared with the more conventional Ca2+-dependent fluorescence microscopic technique, chlortetracycline (CTC) staining, for assessing capacitation status. In addition, the effect of bicarbonate/CO2 on the progress of capacitation and the acrosome reaction (AR) and on temporal changes in sperm motility, with particular regard to hyperactivation, was analyzed. For the study, fresh semen was washed and then incubated for 5 h in bicarbonate-containing or bicarbonate-free medium, with or without Ca2+ ionophore to induce the AR, and at intervals during incubation aliquots were taken and analyzed for capacitation and acrosome status. The AR was assessed using both the CTC and fluorescein isothiocyanate-peanut agglutinin (FITC-PNA) st...
298 citations
Journal Article•
TL;DR: Treatment with Maca resulted in increased seminal volume, sperm count per ejaculum, motile sperm count, and sperm motility and this was not related to dose of Maca.
Abstract: Aim: The present study was designed to determine the effect of a 4-month oral treatment with tablets of Lepidium meyenii (Maca) on seminal analysis in nine adult normal men aged 24-44 years old. Methods: Nine men received tablets of Maca (1500 or 3000 mg/day) for 4 months. Seminal analysis was performed according to guidelines of the World Health Organization (WHO). Serum luteinizing hormone (LH), follicle stimulating hormone (FSH), prolactin (PRL), testosterone (T) and estradiol (E 2 ) were measured before and after treatment. Results: Treatment with Maca resulted in increased seminal volume, sperm count per ejaculum, motile sperm count, and sperm motility. Serum hormone levels were not modified with Maca treatment. Increase of sperm count was not related to dose of Maca. Conclusion : Maca improved sperm production and sperm motility by mechanisms not related to LH, FSH, PRL, T and E 2 .
260 citations
TL;DR: It appears that abnormal protamine levels may reflect defects of late spermiogenesis, including sperm penetration capacity, which is a common defect in infertility patients, but not in donors of known fertility.
Abstract: During the spermatid elongation stage of spermiogenesis approximately 85% of sperm nuclear histones are replaced by protamines. Protamines increase the packing ratio of sperm chromatin, presumably facilitating sperm motility and function. In this study we evaluated the incidence of abnormal protamine expression in 75 patients undergoing in vitro fertilization (IVF) and 50 donors of known fertility by isolation of sperm nuclear proteins, quantitative gel electrophoresis, and Western blot analysis. In addition, we evaluated the relationship between abnormal protamine expression and semen quality, sperm penetration ability, chromatin stability, and IVF outcome. Seventeen percent (13/75) of IVF patients had no measurable protamine 2 (P2) versus 0% (0/50) of donors of known fertility (P < .005). Sperm penetration rates were decreased in 12 of 13 patients without P2, and mean penetration rates (4.6 +/- 1.2 vs 32.8 +/- 2.9, P < .005), normal morphology (22.4 +/- 3.6 vs 48.7 +/- 4.2, P < .05), and progressive motility (22.3 +/- 2.5 vs 35.4 +/- 2.1, P < .05) were all significantly decreased compared with patients with measurable P2. The mean sperm concentration was not significantly different. The presence of protamine precursor bands was also associated with a diminished penetration capacity (18.4 +/- 2.8 vs 36.7 +/- 3.0, P < .05). Sperm chromatin decondensation following exposure to heparin sulfate was significantly increased in patients without a measurable P2 band. Twelve patients with no measurable P2 underwent intracytoplasmic sperm injection (ICSI), with 6 patients (6/12, 50%) becoming pregnant. ICSI fertilization and subsequent embryo cleavage were not different in patients without P2 compared with other patients undergoing ICSI. These data indicate that abnormal sperm protamine levels are a common defect in infertility patients, but not in donors of known fertility. It appears that abnormal protamine levels may reflect defects of late spermiogenesis, including sperm penetration capacity.
TL;DR: Sperm viability and motility in both fresh and thawed samples were similar in classes H and A, while significantly lower values were measured in class L, indicating that active sperm lipid metabolism might be responsible for the increase in lipid content.
Abstract: The effect of cryopreservation on boar sperm viability, motility, lipid content and antioxidant enzymatic activities was studied. Three classes of semen were determined according to a cluster analysis on the basis of the proportion of live and dead cells after freezing and thawing. The classes identified were: high (H, n = 4), average (A, n = 12) and low (L, n = 3) viability. The concentration of sperm cells decreased from class H to A to L. Fresh semen samples with higher viability and a higher proportion of motile cells also maintained better quality after the freezing and thawing procedure. Sperm viability and motility in both fresh and thawed samples were similar in classes H and A, while significantly lower values were measured in class L. The relative decrease in sperm viability and motility after cryopreservation increased from class H to A to L. The lipid content of spermatozoa (micrograms per 10(9) cells) increased significantly after freezing and thawing in classes H and A but not in class L. This result indicated that active sperm lipid metabolism might be responsible for the increase in lipid content. Phospholipid and triacylglycerol contents increased whereas free cholesterol content decreased after thawing. The fatty acid composition of fresh spermatozoa was similar in all three classes. The proportion of polyunsaturated fatty acids decreased significantly after freezing and thawing, indicating contamination from the diluent or peroxidation. After freezing and thawing, superoxide dismutase activity in spermatozoa was significantly higher in class L than in classes H and A, which did not differ from each other.
TL;DR: Investigation of the effects of cryopreservation on both DNA integrity and morphology of spermatozoa from fertile and infertile men found it had a detrimental effect on morphology of semen and prepared samples from fertile, and sperm morphology was significantly damaged by freeze-thawing.
Abstract: Cryopreservation of human spermatozoa is extensively used in artificial insemination and IVF programmes Despite various advances in cryopreservation methodology, the recovery rate of functional post-thaw spermatozoa remains mediocre, with sperm motility being significantly decreased after freezing This aim of this study was to investigate the effects of cryopreservation on both DNA integrity and morphology of spermatozoa from fertile and infertile men Semen samples were obtained from 17 fertile and 40 infertile men All samples were prepared by discontinuous Percoll density centrifugation (950:475) Samples were divided into aliquots to allow direct comparison of fresh and frozen spermatozoa from the same ejaculate Aliquots for cryopreservation were mixed with a commercial cryoprotectant and frozen by static phase vapour cooling before plunging into liquid nitrogen Thawing was carried out slowly at room temperature Sperm DNA integrity was determined using a modified alkaline single cell gel electrophoresis (comet) assay and sperm morphology analysed using the Tygerberg criteria DNA of semen and prepared spermatozoa from fertile men was found to be unaffected by cryopreservation In marked contrast, spermatozoa from infertile men were significantly damaged by freeze-thawing Cryopreservation had a detrimental effect on morphology of semen and prepared samples from fertile and infertile men
TL;DR: The semen analysis results of a fertile population were compared with those from a subfertile population, in order to establish normal cut-off values for the standard semen parameters with the aid of receiver operating characteristic (ROC) curve analysis.
Abstract: In this study, the semen analysis results of a fertile population were compared with those from a subfertile population, in order to establish normal cut-off values for the standard semen parameters with the aid of receiver operating characteristic (ROC) curve analysis. The fertile group comprised healthy males (n = 107) without any history of fertility problems, the partners of whom had had a spontaneous pregnancy within one year of unprotected intercourse and were pregnant at the time of the male's inclusion into the study. A total of 103 males from couples attending the infertility clinic, and with an initial sperm count of <20x10(6)/ml were recruited to form the subfertile population. The best discriminating parameter between the two populations was sperm morphology evaluated according to WHO criteria at a cut-off point of 31% normal spermatozoa. The other cut-off values were at 8% for the acrosome index, 45% for motility, and 4% normal spermatozoa for strict criteria. Recalculating the ROC curve cut-off values based on an assumed 50% prevalence of subfertility in an assisted reproductive setting, the cut-off points were reduced to 21% and 3% normal spermatozoa for WHO and strict criteria respectively. For motility, the new cut-off value was at 20% motile spermatozoa, for motility quality at 3.5 (on a scale of 1-6), the acrosome index at 3% normal acrosomes, and the teratozoospermia index at 2.09.
TL;DR: An increased risk of sperm aneuploidy was not observed in infertile men with poor sperm motility or in those with a normal karyotype and normal semen parameters, and on chromosomal abnormalities in the spermatozoa of infertiles men who have normal somatic karyotypes.
Abstract: Reproductive difficulties are associated intimately with cytogenetic abnormalities. This article reviews multicolour fluorescence in situ hybridization studies on spermatozoa from men with constitutional chromosomal abnormalities and the consequences for spermatozoa, and on chromosomal abnormalities in the spermatozoa of infertile men who have normal somatic karyotypes. In 47,XYY men, the frequencies of 24,XY and 24,YY spermatozoa appear to be < or = 1%. Klinefelter (47,XXY) and mosaic Klinefelter patients had sperm aneuploidy frequencies of 2-25% and 1.5-7.0%, respectively. Robertsonian translocation carriers had 3-27% spermatozoa unbalanced for the chromosomes involved in the translocation, with a possible modest interchromosomal effect, but none of the increased frequencies of chromosomal disomy approached 1%. The frequency of chromosomally unbalanced spermatozoa in reciprocal translocations averages 50%, is strongly dependent on the chromosomes involved in the individual translocation, and may be slightly increased as a result of a small interchromosomal effect. Infertile men with a normal karyotype and low sperm concentration or certain types of morphologically abnormal spermatozoa have a significantly increased risk of producing aneuploid spermatozoa, particularly for the sex chromosomes. An increased risk of sperm aneuploidy was not observed in infertile men with poor sperm motility or in those with a normal karyotype and normal semen parameters.
TL;DR: There were significant differences of the two sperm movement characteristics, including VCL and Rapid (before and after swim-up), indicating that the total distance traveled by rapid sperm movement might be important in human sperm fertilizing abilities.
Abstract: Purpose: Some studies have suggested that computer-aided sperm analysis (CASA) estimates of concentration and movement characteristics of progressively motile spermatozoa are related to fertilization rates in vitro. However, it has also been suggested that the greater number of motility parameters assessed by CASA does not imply more precision in predicting fertility. This study was carried out to investigate the relationships between the CASA estimates and fertilization rates in vitro.
TL;DR: Although calcium, magnesium, zinc, and copper play an essential role in spermatogenesis and fertility, the determination of these elements in blood and seminal plasma does not discriminate on the basis of fertility in this group of men.
TL;DR: Sperm frozen unprepared in seminal fluid appeared more resistant to freezing damage than frozen prepared sperm, suggesting freezing sperm in seminal plasma improves postthaw motility and DNA integrity.
TL;DR: Adding the enzyme scavenger, catalase, or a variety of lipid- and water-soluble antioxidants did not significantly improve the maintenance of motility during liquid semen storage at 5 degrees C.
TL;DR: It is suggested that alternative cryoprotectants should be considered for cryopreservation of equine spermatozoa in order to reduce osmotic stress associated with the addition of these agents during semen freezing.
Abstract: Osmotic stress attributed to differences in the relative permeability of cryoprotectants, such as glycerol and water, appears to be an important factor in cryodamage. The objective of this study was to characterize the osmotic tolerance of equine spermatozoa, and to evaluate the effects of addition and removal of cryoprotectants from equine spermatozoa on their motility, and membrane and acrosomal integrity, as well as their mitochondrial membrane potential. Equine spermatozoa had a limited osmotic tolerance to anisosmotic conditions. Although the addition of increasing concentrations of glycerol decreased the motility and viability of equine spermatozoa, the rapid removal of glycerol by dilution in isosmotic media resulted in an even greater decline in motility and viability compared with spermatozoa maintained under anisosmotic conditions. Likewise, the addition and rapid removal of 1.0 M glycerol, ethylene glycol, dimethylsulfoxide, or propylene glycol resulted in a significant decline in sperm motility and viability. Among these cryoprotectants, ethylene glycol had the least detrimental effect on either viability or motility of spermatozoa following the rapid addition and removal of these cryoprotectants. These data demonstrate that equine spermatozoa have a limited osmotic tolerance compared with published reports for mouse or human spermatozoa, and appear to be more similar to boar spermatozoa in their osmotic tolerance. Of the 4 cryoprotectants evaluated in equine spermatozoa, the addition and removal of glycerol resulted in a more marked osmotic stress as indicated by alterations in motility, viability, and acrosomal integrity. These data suggest that alternative cryoprotectants should be considered for cryopreservation of equine spermatozoa in order to reduce osmotic stress associated with the addition of these agents during semen freezing.
TL;DR: The hypothesis that consistent interindividual variation in sperm freezability is genetically determined and may relate to processes that occur during spermatogenesis is supported.
Abstract: This study investigated two hypotheses: 1) that consistent between-boar variation in frozen semen quality exists and is genetically determined, and 2) that morphologically distinct subpopulations of spermatozoa exist within fresh boar ejaculates and that the incidence of these subpopulations is correlated with semen quality following cryopreservation. Five ejaculates were collected from each of 15 boars (5 boars from each of 3 breeds). An objective sperm morphology analyzer used Fourier shape descriptors to describe variation in the morphology of 300 spermatozoa per ejaculate before freezing. Semen was diluted into a commercial freezing buffer (700 mOsm/kg, 3% glycerol) and 5 straws (0.5 mL) per ejaculate were cryopreserved (to -5 degrees C at 6 degrees C/min, then -5 degrees C to -80 degrees C at 40 degrees C/min). Semen was assessed for percentage of motile cells and motility characteristics (with computer-aided sperm analysis), plasma membrane integrity (SYBR-14 positive), and acrosome integrity (fluorescein-labeled peanut agglutinin positive). Consistent between-boar variability was detected for post-thaw sperm motility (P < .01), membrane integrity (P < .01), acrosome integrity (P < .01), curvilinear velocity (P < .01), straight-line velocity (P < .05), beat cross-frequency (P < .05), and amplitude of lateral head displacement (P < .01). Three morphologically distinct subpopulations of spermatozoa, defined by Fourier descriptors, were detected. The proportion of these subpopulations within the fresh ejaculate correlated with semen quality assessments made following cryopreservation. These findings support the hypothesis that consistent interindividual variation in sperm freezability is genetically determined and may relate to processes that occur during spermatogenesis. Subsequent characterization of these genetic differences between "good" and "poor" freezers may ultimately identify biophysical components of the spermatozoa that are essential for successful cryopreservation.
TL;DR: Armed with a battery of tests, which evaluate many different sperm attributes, researchers should be able to more accurately estimate the fertilizing potential of semen samples.
TL;DR: It is concluded that cryopreservation perturbs sperm membrane sulfhydryl containing proteins and that these modifications could be partially prevented by the addition of GSSG to the cryop Reservation medium.
Abstract: Cryopreservation induces extensive biophysical and biochemical changes in the membrane of spermatozoa that ultimately decrease the fertility potential of the cells. Sulfhydryl groups of sperm proteins regulate a number of activities of the cells. Qualitative and quantitative analyses of sulfhydryl groups in the sperm membrane were performed by fluorescence microscopy, fluorimetry and electrophoresis. Fluorimetric analysis using 5-iodoacetamidofluoresceine indicated a two-fold increase in the content of sulfhydryl groups in sperm membrane after a freezing/thawing cycle. Electrophoresis of Triton-soluble sperm proteins after labeling with 3-(N-maleimidylpropionyl) biocytin indicated that proteins of 40-65 and 34 kDa range expose more sulfhydryl groups after cooling at 4 degrees C and freezing/thawing. Cryopreservation of spermatozoa changed the distribution pattern of sulfhydryl groups on sperm surface measured with fluorescence microscopy using 5-iodoacetamidofluoresceine. The percentage of spermatozoa labeled at the level of the mid-piece decreased by 50 and 90% after cooling and freezing/thawing, respectively. Spin labeling studies showed a 15% faster rotational diffusion (mobility) of sulfhydryl containing proteins in the membrane of frozen/thawed spermatozoa as compared to that of fresh spermatozoa. Addition of glutathione, reduced (GSH) or oxidized (GSSG), to the cryoprotectant partially prevented the effects of freezing/thawing, such as higher exposure of sulfhydryl groups, changes in the cellular distribution, and enhanced rotational diffusion of sulfhydryl containing proteins of sperm membrane. Addition of GSSG to the cryoprotectant reduced by 35% the loss of motility of spermatozoa undergoing a freezing/thawing cycle. We concluded that cryopreservation perturbs sperm membrane sulfhydryl containing proteins and that these modifications could be partially prevented by the addition of GSSG to the cryopreservation medium.
TL;DR: The nonreturn rate (NRR) and the number of live-born piglets were compatible with the requirements of artificial insemination for all boars included in this study and concentrations of IGF-I and IGF-II in seminal plasma were determined.
Abstract: This study was conducted to investigate the relationships between results of computer-assisted semen analysis (spermatozoal motility and sperm head morphometry) and fertility of boars. In addition, concentrations of insulin-like growth factor (IGF)-I and IGF-II in seminal plasma were determined. The nonreturn rate (NRR) and the number of live-born piglets were compatible with the requirements of artificial insemination for all boars included in this study. Semen samples of 12 boars (Pietrain; 3 ejaculates each) were evaluated for spermatozoal motility and sperm head dimensions using computer-assisted methods. Native semen samples were centrifuged, and seminal plasma was frozen at -20 degrees C until assayed for IGF-I and IGF-II by specific radioimmunoassays. Spermatozoa of boars with a higher NRR (>86%) had a significantly slower average velocity of motile spermatozoa when compared with that of boars with an NRR below 86%. High-fertility boars (NRR > 86%) had significantly smaller sperm heads than did boars with an NRR below 86%, and their sperm heads were less elongated. Substantial concentrations of IGF-I (8.4-22.2 ng/mL) and IGF-II (12.1-19.8 ng/mL) could be measured in porcine seminal plasma; however, there was no correlation between IGF levels and semen parameters or individual fertility.
TL;DR: Evidence is provided for the expression of seven Drosophila transient receptor potential homolog genes and three of their protein products in mouse sperm and one of these proteins (Trp1) co‐immunolocalized with caveolin‐1, a major component of caveolae, a subset of lipid rafts potentially important for signaling events and Ca2+ flux.
Journal Article•
TL;DR: The present review has been designed to update the recent developments on the function of seminal vesicles and their role on male fertility and it is indicated that the true corrected fructose level is a simple method for the assessment of the seminalvesicular function.
Abstract: The present review has been designed to update the recent developments on the function of seminal vesicles and their role on male fertility. It is indicated that the true corrected fructose level is a simple method for the assessment of the seminal vesicular function. Measurement of seminal fructose used universally as a marker of the seminal vesicle function is not an appropriate approach due to its inverse relationship with the sperm count. The true corrected fructose defined as [log. motile sperm concentration] multiplied by [seminal fructose concentration] has been shown to be a better marker of the seminal vesicle function. Seminal vesicular secretion is important for semen coagulation, sperm motility, and stability of sperm chromatin and suppression of the immune activity in the female reproductive tract. In conclusion, the function of seminal vesicle is important for fertility. Parameters as sperm motility, sperm chromatin stability, and immuno-protection may be changed in case of its hypofunction.
TL;DR: A new integrated approach including computer assisted sperm analysis (CASA), viability staining and fertilization was used to study the quality of cryodiluents used in fish sperm cryopreservation as mentioned in this paper.
TL;DR: The results establish that, in sperm competition with dominant males, parr males may compensate for behavioural subordinance by producing physiologically superior spermatozoa.
Abstract: 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.
TL;DR: Coadministration of vitamin E with mercuric chloride prevented the changes in sperm and biochemical parameters and was associated with control rates of sperm positive smears after cohabitation and has a protective role against mercury-induced male reproductive toxicity.
TL;DR: It is concluded that the normal swim-up technique caused no more DNA damage to spermatozoa from normal semen samples than a direct swim- up technique that involved no centrifugation step.
Abstract: BACKGROUND: Swim-up techniques for sperm separation may have detrimental effects on sperm DNA. We wished to determine whether the normal swim-up method with centrifugation used in our laboratory, which involves a centrifugation step, was harmful to sperm compared with swim-up without centrifugation. METHODS: Semen samples were obtained from patients undergoing IVF or andrology assessment. An aliquot was removed for fixation and subsequent DNA fragmentation determination. The remaining sample was divided into two equal parts, which were subjected to swim-up either with (normal swim-up) or without (direct-swim-up) centrifugation. Semen analysis was performed both before and after swim-up. DNA fragmentation, in spermatozoa previously fixed in 4% paraformaldehyde, was assessed by the terminal transferase-mediated DNA end-labelling procedure (TUNEL). The percentage of spermatozoa with DNA damage after each swim-up technique was compared with that in the original semen sample. RESULTS: DNA damage was <5% in most samples. No significant change in DNA fragmentation was observed between the two swim-up procedures, although the ‘normal’ swim-up sample had significantly less DNA fragmentation than the pre-swim-up sample. CONCLUSIONS: We conclude that our normal swim-up technique caused no more DNA damage to spermatozoa from normal semen samples than a direct swim-up technique that involved no centrifugation step.