Showing papers on "Sperm motility published in 2003"

Sperm preparation for ART.

Abstract: The onset of clinical assisted reproduction, a quarter of a century ago, required the isolation of motile spermatozoa. As the indication of assisted reproduction shifted from mere gynaecological indications to andrological indications during the years, this urged andrological research to understand the physiology of male germ cell better and develop more sophisticated techniques to separate functional spermatozoa from those that are immotile, have poor morphology or are not capable to fertilize oocytes. Initially, starting from simple washing of spermatozoa, separation techniques, based on different principles like migration, filtration or density gradient centrifugation evolved. The most simple and cheapest is the conventional swim-up procedure. A more sophisticated and most gentle migration method is migration-sedimentation. However, its yield is relatively small and the technique is therefore normally only limited to ejaculates with a high number of motile spermatozoa. Recently, however, the method was also successfully used to isolate spermatozoa for intracytoplasmic sperm injection (ICSI). Sperm separation methods that yield a higher number of motile spermatozoa are glass wool filtration or density gradient centrifugation with different media. Since Percoll® as a density medium was removed from the market in 1996 for clinical use in the human because of its risk of contamination with endotoxins, other media like IxaPrep®, Nycodenz, SilSelect®, PureSperm® or Isolate® were developed in order to replace Percoll®. Today, an array of different methods is available and the selection depends on the quality of the ejaculates, which also includes production of reactive oxygen species (ROS) by spermatozoa and leukocytes. Ejaculates with ROS production should not be separated by means of conventional swim-up, as this can severely damage the spermatozoa. In order to protect the male germ cells from the influence of ROS and to stimulate their motility to increase the yield, a number of substances can be added to the ejaculate or the separation medium. Caffeine, pentoxifylline and 2-deoxyadenosine are substances that were used to stimulate motility. Recent approaches to stimulate spermatozoa include bicarbonate, metal chelators or platelet-activating factor (PAF). While the use of PAF already resulted in pregnancies in intrauterine insemination, the suitability of the other substances for the clinical use still needs to be tested. Finally, the isolation of functional spermatozoa from highly viscous ejaculates is a special challenge and can be performed enzymatically to liquefy the ejaculate. The older method, by which the ejaculate is forcefully aspirated through a narrow-gauge needle, should be abandoned as it can severely damage spermatozoa, thus resulting in immotile sperm.

Sperm DNA fragmentation decreases the pregnancy rate in an assisted reproductive technique

Abstract: BACKGROUND: Standard sperm characteristics are poor predictors of the outcome of IVF treatments. On the contrary, sperm genome quality has been emphasized for several years as playing a major role in early embryogenesis, thus in the success of IVF attempt. METHODS: Sperm DNA fragmentation from a selected group of 104 couples undergoing assisted reproductive techniques (ART) (IVF: n = 50; and ICSI: n = 54) was measured by TUNEL assay and correlated with semen and ART outcomes. RESULTS: A negative correlation was found between sperm characteristics and the proportion of sperm showing DNA fragmentation. For fragmentation >10%, a significant decrease of the fertilization rate was observed. No correlation was found between sperm DNA fragmentation and embryo quality. A high proportion of sperm with fragmented DNA was a pejorative factor to obtain pregnancies when ICSI was performed, but there was no relationship when conventional IVF was performed. CONCLUSIONS: The proportion of sperm with DNA fragmentation appears to be potentially useful as a predictor of ICSI outcome, whereas embryo quality based on morphological criteria, appeared unaffected by DNA fragmentation.

Hyperactivated sperm motility driven by CatSper2 is required for fertilization

Abstract: Elevations of sperm Ca2+ seem to be responsible for an asymmetric form of motility called hyperactivation, which is first seen near the time of fertilization. The mechanism by which intracellular Ca2+ concentrations increase remains unknown despite considerable investigation. Although several prototypical voltage-gated calcium channels are present in spermatozoa, they are not essential for motility. Furthermore, the forward velocity and percentage of motility of spermatozoa are associated with infertility, but their importance relative to hyperactivation also remains unknown. We show here that disruption of the gene for a recently described sperm-specific voltage-gated cation channel, CatSper2, fails to significantly alter sperm production, protein tyrosine phosphorylation that is associated with capacitation, induction of the acrosome reaction, forward velocity, or percentage of motility, yet CatSper2–/– males are completely infertile. The defect that we identify in the null sperm cells is a failure to acquire hyperactivated motility, which seems to render spermatozoa incapable of generating the “power” needed for penetration of the extracellular matrix of the egg. A loss of power is suggested also by experiments in which the viscosity of the medium was increased after incubation of spermatozoa in normal capacitating conditions. In high-viscosity medium, CatSper2-null spermatozoa lost the ability to swim forward, whereas wild-type cells continued to move forward. Thus, CatSper2 is responsible for driving hyperactivated motility, and, even with typical sperm forward velocities, fertilization is not possible in the absence of this highly active form of motility.

The association of age and semen quality in healthy men

Abstract: Background Although the effect of maternal age on fertility is well known, it is unclear whether paternal age also affects fertility. This cross-sectional study sought to characterize the association between age and semen quality, a well-known proxy of fertility status. Methods A convenience sample of 97 non-smoking men (aged 22-80 years) without known fertility problems was recruited from a national government laboratory. The men provided semen samples and information relating to lifestyle, diet, medical and occupational details. Semen volume (ml), sperm concentration (x10(6)/ml), total sperm count (x10(6)), motility (%), progressive motility (%) and total progressively motile sperm count (x10(6)) were measured. Results After adjusting for covariates, semen volume decreased by 0.03 ml per year of age (95% CI: -0.05, -0.01); motility decreased by 0.7% per year (95% CI: -0.92, -0.43); progressive motility decreased by 3.1% per year (95% CI: -4.5, -1.6); and total progressively motile sperm count decreased by 4.7% per year (95% CI: -7.2, -2.2). There was a suggested decrease in sperm concentration and count. The proportion of men with abnormal volume, concentration and motility was significantly increased across the age decades. Conclusions In a convenience sample of healthy men from a non-clinical setting, semen volume and sperm motility decreased continuously between 22-80 years of age, with no evidence of a threshold.

Fibrous sheath of mammalian spermatozoa.

Abstract: The fibrous sheath is a unique cytoskeletal structure surrounding the axoneme and outer dense fibers and defines the extent of the principal piece region of the sperm flagellum. It consists of two longitudinal columns connected by closely arrayed semicircular ribs that assemble from distal to proximal throughout spermiogenesis. The fibrous sheath is believed to influence the degree of flexibility, plane of flagellar motion, and the shape of the flagellar beat. Nearly half of the protein in fibrous sheaths isolated from mouse sperm is AKAP4. This protein and two others, AKAP3 and TAKAP-80, have anchoring sites for cAMP-dependent protein kinase. AKAP3 also anchors ropporin, a spermatogenic cell-specific protein that is linked through rhophilin to the small GTPase Rho. Other proteins associated with the fibrous sheath include two enzymes in the glycolytic pathway. Glyceraldehyde 3-phosphate dehydrogenase-s (GAPDS) is the product of a gene expressed only in spermatogenic cells, while hexokinase type 1-s (HK1-S) is derived from alternative transcripts present only in spermatogenic cells. Most of the other glycolytic enzymes in sperm have unique structural or functional properties. The fibrous sheath also contains a spermatogenic cell-specific member of the mu-class glutathione S-transferase family (GSTM5) and an intermediate filament-like protein (FS39). These and other observations indicate that the fibrous sheath functions as a scaffold for proteins in signaling pathways that might be involved in regulating sperm maturation, motility, capacitation, hyperactivation, and/or acrosome reaction and for enzymes in the glycolytic pathway that provide energy for the hyperactivated motility of sperm that allows them to penetrate the zona pellucida.

Passively driven integrated microfluidic system for separation of motile sperm

Abstract: This paper describes a self-contained integrated microfluidic system that can separate motile sperm from small samples that are difficult to handle using conventional sperm-sorting techniques. The device isolates motile sperm from nonmotile sperm and other cellular debris, based on the ability of motile sperm to cross streamlines in a laminar fluid stream. The device is small, simple, and disposable yet is an integrated system complete with sample inlets, outlets, sorting channel, and a novel passively driven pumping system that provides a steady flow of liquid; it requires no external power source or controls. The device fulfills a need in clinical settings where small amounts of sperm need to be sorted. It also opens the way for convenient bioassays based on sperm motility including at-home motile sperm tests.

Laboratory semen assessment and prediction of fertility: still utopia?

Abstract: Finding a laboratory test reliable enough to predict the potential fertility of a given semen sample or a given sire for artificial insemination (AI) is still considered utopian, as indicated by the modest correlations seen between results obtained in vitro and field fertility. Male fertility is complex, and depends upon a heterogeneous population of spermatozoa interacting at various levels of the female genital tract, the vestments of the oocyte, and the oocyte itself. For this reason, laboratory assessment of semen must include the testing of most sperm attributes relevant for fertilization and embryo development, not only in individual spermatozoa but within a large sperm population as well. Strategies for the discovery of in vitro predictors of semen fertility require evaluations of low sperm doses for AI, so that differences in innate in vivo fertility can be accurately detected.

Evaluation of the one‐step eosin‐nigrosin staining technique for human sperm vitality assessment

Abstract: BACKGROUND: The one-step eosin-nigrosin staining technique for assessment of sperm vitality was developed in the 1950s for various mammalian species. Although commonly used on human sperm in semen, a validation for this use has not previously been published. METHODS: The technique was evaluated on 1235 consecutive semen samples. RESULTS: The one-step eosin-nigrosin staining technique gave valid results when evaluated with sperm motility data obtained according to World Health Organization standard (1992, 1999). The mean for the sums of stained (i.e. supposedly dead) and motile sperm using the one-step eosin-nigrosin technique was 91% (SD 6 10%). The distribution of sums for percentage stained and percentage motile sperm was similar, regardless of whether the samples had many or few dead sperm. CONCLUSIONS: Standardization and quality control of basic semen analysis demands robust, reliable and simple techniques that are easy to learn, and easy to continue to perform in the same way. The one-step eosin-nigrosin technique does not need negative phase contrast optics but can be run with ordinary bright-field microscopy. Since it also includes fewer methodological steps to control, it seems preferable in terms of standardization and quality control management. It should therefore be recommended in the basic semen analysis when sperm vitality is to be assessed.

Sperm pathology: a step beyond descriptive morphology. Origin, characterization and fertility potential of abnormal sperm phenotypes in infertile men

Abstract: Sperm pathology is presented as the discipline of characterizing structural and functional deficiencies in abnormal spermatozoa. This concept complements that of sperm morphology mainly concerned with the appearance of spermatozoa. These two notions collaborate in providing correlations of prognostic value with sperm fertilizing capacity, explaining the mechanisms of sperm inefficiency, suggesting strategies to improve fertilization and opening a door to molecular genetic studies. Phenotypes of genetic origin involving sperm heads, flagella and the neck region are presented describing their clinical manifestations, sperm structure, cytochemistry and genetic background. When available, animal models are used to highlight possible genetic mechanisms. Sperm pathologies secondary to andrological conditions or environmental factors are described, stressing the non-specific nature of the sperm response to noxious agents. The available literature on the prognostic value of sperm pathologies in ICSI is also reviewed. Flagellar anomalies bear a good prognosis, but those affecting the acrosome, sperm chromatin and the neck region entail an increasing chance of failure, which highlights the differential roles played by specific sperm components in fertilization, implantation and early embryonic development. A final discussion is devoted to genetic counselling and the risks involved in using immotile or abnormal spermatozoa in assisted reproduction.

Trehalose-Enhanced Fluidity of the Goat Sperm Membrane and Its Protection During Freezing

Abstract: In an attempt to find a suitable freezing method for goat semen, two experiments were conducted to study the influence of trehalose on the cryopreservation of goat spermatozoa. In experiment 1, goat spermatozoa were frozen in trehalose extender (0.375 M) alone (100%) or at different combinations of trehalose with Tris-citric acid-glucose (TCG) extender (0%, 25%, 50%, 75%). Final concentrations of 20% (v:v) egg yolk and 4% (v:v) glycerol were employed in the extenders (osmolality = 370, pH = 7). Sperm motility was assessed using a computer-assisted sperm analysis system and acrosome integrity was assessed using fluorescein isothiocyanate-labeled peanut agglutinin (FITC-PNA). The sperm-motility parameters improved significantly by increasing the concentration of trehalose (P < 0.05) and significantly high recovery rates for the motility parameters were also achieved by a high concentration of trehalose (P < 0.05). Motility of the frozen-thawed spermatozoa after a 3-h incubation improved significantly with increasing concentrations of trehalose in the extender (P < 0.05). The 75% and 100% trehalose extenders yielded a significant increase in the percentage of spermatozoa with intact acrosome (P < 0.05). In experiment 2, merocyanine 540/Yo-Pro staining was used to study the influence of trehalose on membrane fluidity compared with that of sucrose and TCG. Percentage of cells with high merocyanine fluorescence was significantly higher in spermatozoa treated with trehalose than sucrose or TCG (P < 0.05), indicating a significantly highest membrane fluidity of sperm samples extended with trehalose solution. We thus conclude that the substitution of a Tris-citric acid diluent composition with trehalose significantly improves the freezability of goat spermatozoa. Furthermore, the cryoprotective effects of trehalose observed in this study may be due to enhanced sperm membrane fluidity before freezing.

A new sperm-specific Na^+/H^+ Exchanger required for sperm motility and fertility

Abstract: It has long been speculated that intracellular pH is a critical regulator of both invertebrate and vertebrate sperm motility1,2,3, and sodium–hydrogen exchange has been suggested as a mediator of such pHi regulation in various instances4,5 Two sodium–hydrogen exchangers (NHE1 and NHE5) are expressed in spermatozoa6 However, elimination of the NHE1 gene fails to cause infertility7, suggesting that normal sperm function is maintained in NHE1-null animals Here, we used a functionally unbiased signal peptide trap screen to identify a novel sperm-specific NHE The NHE contains 14 predicted transmembrane segments, including a potential voltage sensor and a consensus cyclic nucleotide-binding motif Testis histology, sperm numbers and morphology were normal, but NHE-null males were completely infertile with severely diminished sperm motility The addition of ammonium chloride, which elevates intracellular pH, partially rescued the motility and fertility defects Surprisingly, cyclic AMP analogues almost completely rescued the motility and infertility phenotypes The existence of this new sperm NHE provides an attractive contraceptive target, given its cell-specific expression and absolute requirement for fertility

Characterization of the Intracellular Calcium Store at the Base of the Sperm Flagellum That Regulates Hyperactivated Motility

Abstract: Hyperactivated sperm motility is usually characterized by high-amplitude flagellar bends and asymmetrical flagellar beating. There is evidence that an inositol 1,4,5-trisphosphate (IP3) receptor-gated Ca2+ store in the base of the flagellum provides Ca2+ to initiate hyperactivation; however, the identity of the store was not known. Ca2+ stores are membrane-bounded organelles, and the only two membrane-bounded organelles found in this region of sperm are the redundant nuclear envelope (RNE) and mitochondria. Transmission electron micrographs revealed two different compartments of RNE, one enriched with nuclear pores and the other containing few pores but extensive membranous structures with enlarged cisternae. Immunolabeling showed that IP3 receptors and calreticulin are located in the region containing enlarged cisternae. In other cell types, mitochondria adjacent to Ca2+ stores are actively involved in modulating Ca2+ signals by taking up Ca2+ released from stores and also may respond by increas...

Molecular Architecture of the Sperm Flagella: Molecules for Motility and Signaling

Abstract: Sperm motility is generated by a highly organized, microtubule-based structure, called the axoneme, which is constructed from approximately 250 proteins. Recent studies have revealed the molecular structures and functions of a number of axonemal components, including the motor molecules, the dyneins, and regulatory substructures, such as radial spoke, central pair, and other accessory structures. The force for flagellar movement is exerted by the sliding of outer-doublet microtubules driven by the molecular motors, the dyneins. Dynein activity is regulated by the radial spoke/central pair apparatus through protein phosphorylation, resulting in flagellar bend propagation. Prior to fertilization, sperm exhibit dramatic motility changes, such as initiation and activation of motility and chemotaxis toward the egg. These changes are triggered by changes in the extracellular ionic environment and substances released from the female reproductive tract or egg. After reception of these extracellular signals by specific ion channels or receptors in the sperm cells, intracellular signals are switched on through tyrosine protein phosphorylation, Ca2+, and cyclic nucleotide-dependent pathways. All these signaling molecules are closely arranged in each sperm flagellum, leading to efficient activation of motility.

Protein phosphorylation in mammalian spermatozoa.

Abstract: Spermatozoa undergo a series of changes before and during egg binding to acquire the ability to fuse with the oocyte. These priming events are regulated by the activation of compartmentalized intracellular signalling pathways, which control the phosphorylation status of sperm proteins. Increased protein tyrosine phosphorylation is associated with capacitation, hyperactivated motility, zona pellucida binding, acrosome reaction and sperm-oocyte binding and fusion. The main tyrosine phosphorylated proteins during the course of capacitation and fertilization are localized to the flagellum, although tyrosine phosphorylation of less abundant proteins may also be regulated in the sperm head. Spermatozoa bound to the zona pellucida and fusing with the oocyte plasma membrane are characterized by a tyrosine phosphorylated flagellum. Protein phosphorylation in the flagellum is linked to hyperactivated motility in spermatozoa, but may also regulate additional functions involved in sperm-oocyte fusion. Factors involved in the appearance of phosphorylation more likely arise from the milieu surrounding the spermatozoa, but their uptake and processing are likely to be regulated differentially at specific steps within the female genital tract and during penetration of the egg vestments. One of these factors is glucose, the metabolic products of which (ATP and NADPH) appear to participate in signalling pathways by supporting a precise onset of tyrosine phosphorylation in the sperm flagellum leading to successful fertilization.

Asthenozoospermia: analysis of a large population.

Abstract: Spermatozoa travel a long distance to meet and fertilize the oocyte, so sperm motility is a requisite for normal fertilization. Asthenozoospermia, or low sperm motility, is a common cause of human male infertility. This is a retrospective study (1992-1999) to document the prevalence of this pathology in infertile men and to clarify the probable factors associated to its etiology. The prevalence was 18.71% for asthenozoospermia and 63.13% for asthenozoospermia associated with oligo- and/or teratozoo-spermia; thus, 81.84% of the studied samples had altered motility. Leukocytospermia, the ratio of germ cells/sperm, anti-sperm antibodies, consistency, biochemical markers of accessory sex glands, and sperm response after swim-up were studied in normospermic (N), asthenozoospermic (A), and combined asthenozoospermic (C) samples. No significant difference was found in the frequency of leukocytospermia among groups. The rate of germ cells/(spermatozoa + germ cells) between C and N (p < .01) and C and A (p < .01) was statistically different, while no difference was found on comparing N and A. MAR-test over 40% was found in 6% of the A samples and 7.6% of the C, while no positive values were observed in the N group. The percentage of hyperviscous samples was higher in the low sperm motility samples than in the normal group. Data on concentration of the biochemical markers seem to be decreased in asthenozoospermia. Pure and combined asthenozoo-spermia showed different behavior in sperm recovery after swim-up. Two different asthenozoospermias could be defined: the pure one where sperm environment is involved (immunological factor, hyperviscosity, and secretory gland function) and the combined, where the testis is comprised.

The predictive value of semen analysis in the evaluation of stallion fertility.

Abstract: Pregnancy rates in managed horse populations depend on the innate fertility of the mares and stallions involved and on the quality of breeding management. Of course, because a single stallion usually mates many mares, stallion fertility is a critical factor in the overall success of a breeding program. Unfortunately, accurate evaluation of stallion fertility per se requires a large number of normal mares to be mated and is necessarily retrospective. Rather, the ideal is to predict fertility in advance of the stallion's breeding career, and this is currently attempted by way of a thorough physical examination and a routine analysis of semen quality. However, while such a 'breeding soundness examination' identifies stallions that clearly lack the capacity for adequate fertility, it is of limited use for predicting the level of fertility and fails to identify some seriously sub-fertile animals. Similarly, while various sperm function tests (e.g., sperm head morphometry, the hypoosmotic swelling test, glass wool-sephadex filtration, progesterone receptor exposure) have been shown to correlate fairly well with fertility in the field, most examine only a single or a narrow range of the attributes that a sperm must possess if it is to fertilize an oocyte in vivo, and are thus more useful for identifying specific causes of sub-fertility than for predicting the level of fertility. On the other hand, combining the results of the various sperm function tests does improve the reliability of fertility estimation and current research is therefore concentrated on identifying a range of tests that covers as many important sperm attributes as possible but that can be performed rapidly and cheaply. In this respect, flow-cytometry has proven to be an ideal tool because it allows the objective, rapid and simultaneous analysis of a number of properties in a large number of sperm. Moreover, stains are available for an increasing range of sperm characteristics including viability, capacitation and acrosome status, mitochondrial activity and chromatin integrity. Flow-cytometric analysis of sperm with appropriate probes thus offers considerable promise for the prediction of stallion fertility.

Traffic pollutants affect fertility in men

Abstract: BACKGROUND: Given the lack of consensus about the effect of traffic-derived pollutants on male fertility, we evaluated semen quality in men occupationally exposed to traffic. METHODS: Semen quality was investigated in 85 men employed at motorway tollgates and in 85 age-matched men living in the same area. Semen, circulating sex hormones, methaemoglobin, sulphaemoglobin, carboxyhaemoglobin, lead (Pb) and zinc (Zn) protoporphyrin were assayed. Environmental carbonium oxide, nitrogen oxide, sulphur oxide and Pb were also measured. RESULTS: Sperm count, and serum levels of FSH, LH and testosterone were within normal range in both groups. Total motility, forward progression, functional tests and sperm kinetics were significantly lower in tollgate workers versus controls. In a subset of tollgate workers with motility below normal, methaemoglobin was inversely correlated with total motility, viability, the hypo-osmotic swelling test, the acridine orange test, the cervical mucus penetration test, linearity, and amplitude of lateral movement of the sperm head, whereas blood levels of Pb were inversely correlated with viability and sperm count. CONCLUSIONS: The finding that blood methaemoglobin and Pb were inversely correlated with sperm parameters indicates that nitrogen oxide and Pb adversely affect semen quality.

The signal flow and motor response controling chemotaxis of sea urchin sperm

Abstract: The signalling pathway and the behavioural strategy underlying chemotaxis of sperm are poorly understood. We have studied the cellular events and motor responses that mediate chemotaxis of sperm from the sea urchin Arbacia punctulata. Here we show that resact, a chemoattractant peptide, initiates a rapid and transient rise in the concentration of cyclic GMP, followed by a transient influx of Ca2+. The binding of a single resact molecule elicits a Ca2+ response, and 50-100 bound molecules saturate the response. The ability to register single molecules is reminiscent of the single-photon sensitivity of rod photoreceptors. Both resact and cyclic nucleotides cause a turn or brief tumbling in the swimming path of sperm. We conclude that a cGMP-mediated increase in the Ca2+ concentration induces the primary motor response of sperm to the chemoattractant.

The relationship between human semen parameters and environmental exposure to polychlorinated biphenyls and \(p,p'\)-DDE

Abstract: Scientific and public concern exists about potential reproductive health effects of persistent chlorinated organic chemicals, such as polychlorinated biphenyls (PCBs), dichlorodiphenyltrichloroethane (DDT), and dichlorodiphenyldichloroethylene (DDE, the most stable daughter compound of DDT). To explore the hypothesis that environmental exposures to PCBs and DDE are associated with altered semen parameters, we conducted a cross-sectional study of 212 male partners of subfertile couples who presented to the Massachusetts General Hospital Andrology Laboratory. Semen parameters were analyzed as both a continuous measure and dichotomized based on World Health Organization reference values for sperm concentration (< 20 million/mL), motility (< 50% motile), and Kruger strict criteria for morphology (< 4% normal). The comparison group for the dichotomized analysis was men with all three semen parameters above the reference values. In serum, 57 PCB congeners and p,p -DDE were measured by congener-specific analysis using gas chromatography with electron capture detection. There were dose-response relationships among PCB-138 and sperm motility (odds ratio per tertile, adjusted for age, abstinence, and smoking, and p-value for trend were, respectively, 1.00, 1.68, 2.35, and p-value = 0.03) and morphology (1.00, 1.36, 2.53, p-value = 0.04). There was limited evidence of an inverse relationship between sum of PCBs, as well as those PCBs classified as cytochrome P450 enzyme inducers, with sperm motility and sperm morphology, as well as limited evidence of an inverse association between p,p -DDE and sperm motility. The lack of a consistent relationship among semen parameters and other individual PCB congeners and groupings of congeners may indicate a difference in spermatotoxicity between congeners.

The associations among semen quality, oxidative DNA damage in human spermatozoa and concentrations of cadmium, lead and selenium in seminal plasma.

Abstract: To explore the associations among semen quality, oxidative DNA damage in human spermatozoa and concentrations of cadmium, lead and selenium in seminal plasma, 56 non-smoking subjects were asked to collect semen by masturbation into a sterile wide-mouth metal-free plastic container after 3 days of abstinence. The conventional semen parameters were analysed. The concentrations of Cd, Pb and Se in seminal plasma were detected using atomic absorption spectrophotometer. 8-OHdG levels in sperm DNA were measured using HPLC-EC. The results showed that the geometric mean concentrations of Cd, Pb and Se were 0.78, 7.8 and 51.4 microg/l, respectively. The geometric mean of 8-OHdG/10(6) dG was 51.4 (95% CI: 21.5-123.0). A significant inverse correlation exists between Cd and sperm density (r=-0.28, P<0.05), and between Cd and sperm number per ejaculum (r=-0.27, P<0.05). In contrast, there was a significantly positive correlation between Se and sperm density (r=0.50, P<0.01), between Se and sperm number (r=0.49, P<0.01), between Se and sperm motility (r=0.40, P<0.01), and between Se and sperm viability (r=0.38, P<0.01). No statistically significant correlation was observed between Pb and semen quality. A significant inverse correlation was observed between 8-OHdG and sperm density (r=-0.34, P<0.01), between 8-OHdG and sperm number per ejaculum (r=-0.30, P<0.01), and 8-OHdG and sperm viability (r=-0.24, P<0.05). 8-OHdG was significantly correlated with Cd in seminal plasma (r=0.55, P<0.01). A significant but weak positive correlation was found between 8-OHdG and Pb concentration in seminal plasma (r=0.28, P<0.05). In contract, a significant inverse correlation was observed between 8-OHdG and Se concentration in seminal plasma (r=-0.40, P<0.01). The results indicate that Cd in seminal plasma could affect semen quality and oxidative DNA damage in human spermatozoa. Se could protect against oxidative DNA damage in human sperm cells. Pb did not appear to have any association with the semen quality when concentration of Pb in seminal plasma was below 10 microg/l.

History of febrile illness and variation in semen quality

Abstract: BACKGROUND: The purpose of this study was to analyse the effect of a history of febrile illness on semen quality. METHODS: Twenty-seven healthy men (median age 24.4 years) were followed with monthly semen samples and a daily record of the occurrence of experienced febrile episodes over a 16 month period between March 1998 and June 1999 in Copenhagen, Denmark. Semen samples were analysed for semen volume, sperm concentration, percentage immotile sperm and percentage morphologically normal sperm. RESULTS: Sperm concentration significantly decreased by 32.6% (95% confidence interval ‐49.9; ‐9.2) following fever during meiosis and by 35.0% (‐50.5; ‐14.6) following fever during the postmeiotic period of spermatogenesis (spermiogenesis). The percentage of morphologically normal sperm was decreased by 7.4% (‐11.6; ‐3.0) and the percentage of immotile sperm was increased by 20.4% (6.0; 36.8) by fever during spermiogenesis. The number of days the men experienced fever significantly affected their semen parameters. Thus fever during meiosis and spermiogenesis reduced sperm concentration with respectively 7.1% (‐12.9; ‐0.9) and 8.5% (‐13.6; ‐3.0) per day of fever. The percentage of morphologically normal sperm decreased 1.6% (‐2.5; ‐0.6) and the percentage of immotile sperm increased 4.5% (1.7; 7.3) per day of fever during spermiogenesis. There was, however, a large variation in the individual response to fever. CONCLUSIONS: Sperm concentration, morphology and motility in a semen sample are adversely affected by a febrile episode during the postmeiotic period of spermatogenesis (spermiogenesis). Sperm concentration was also adversely affected by fever during the period of meiosis, whereas fever at other time points during spermatogenesis did not seem to significantly affect these sperm parameters. The adverse effect seemed to be dependent upon the number of days with fever.