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Showing papers on "Semen published in 2007"


Journal ArticleDOI
TL;DR: Diabetes is associated with increased sperm nuclear and mtDNA damage that may impair the reproductive capability of men attending fertility clinics and this work aims to address this concern.
Abstract: BACKGROUND: Diabetes mellitus (DM) is increasing in men of reproductive age. Despite this, the prevalence of diabetes in men attending fertility clinics is largely unknown. Furthermore, studies examining the effects of DM on sperm fertility potential have been limited to conventional semen analysis. METHODS: Conventional semen analysis (semen volume, sperm count, motility and morphology) was performed for 27 diabetic (mean age 34 ± 2 years) and 29 non-diabetic subjects (control group, men undergoing routine infertility investigations, mean age 33 ± 1 years). Nuclear DNA (nDNA) fragmentation was assessed using the alkaline Comet assay and mitochondrial DNA (mtDNA) deletions by Long-PCR. RESULTS: Other than a small, but significant, reduction in semen volume in diabetic men (2.6 versus 3.3 ml; P < 0.05), conventional semen parameters did not differ significantly from control subjects. Diabetic subjects had significantly higher mean nDNA fragmentation (53 versus 32%; P < 0.0001) and median number of mtDNA deletions (4 versus 3; P < 0.05) compared with control subjects. CONCLUSIONS: Diabetes is associated with increased sperm nuclear and mtDNA damage that may impair the reproductive capability of these men.

440 citations


Journal ArticleDOI
20 Aug 2007-AIDS
TL;DR: These results provide a biological explanation for reported increases in HIV transmission during the very early (acute) and late stages of infection.
Abstract: OBJECTIVES This study was conducted to compare viral dynamics in blood and semen between subjects with antibody negative, acute HIV-1 infection and other subjects with later stages of infection. DESIGN A prospective cohort study was embedded within a cross-sectional study of HIV screening in a Lilongwe, Malawi STD clinic. METHODS Blood samples from HIV antibody negative or indeterminate volunteers were used to detect HIV RNA in plasma using a pooling strategy. Blood and seminal plasma HIV-1 RNA concentrations were measured over 16 weeks. RESULTS Sixteen men with acute HIV infection and 25 men with chronic HIV infection were studied. Blood viral load in subjects with acute HIV infection was highest about 17 days after infection (mean +/- SE, 6.9 +/- 0.5 log10 copies/ml), while semen viral load peaked about 30 days after infection (4.5 +/- 0.4 log10 copies/ml). Semen viral load declined by 1.7 log10 to a nadir by week 10 of HIV infection. Semen and blood viral loads were more stable in chronically infected subjects over 16 weeks. Higher semen levels of HIV RNA were noted in subjects with low CD4 cell counts. CONCLUSIONS These results provide a biological explanation for reported increases in HIV transmission during the very early (acute) and late stages of infection. Recognizing temporal differences in HIV shedding in the genital tract is important in the development of effective HIV prevention strategies.

303 citations


Journal ArticleDOI
TL;DR: It is shown that seminal plasma can elicit expression of a range of inflammatory cytokines and chemokines in reproductive tract epithelia, and implicate the ectocervix as the primary site of responsiveness, with gene-specific differences in the kinetics and site-restrictedness of the response.
Abstract: Exposure to semen elicits an inflammatory response in the female reproductive tract of rodents and other animals. The nature and regulation of any similar response in humans is poorly understood. This study investigated seminal plasma induction of inflammatory cytokine and chemokine gene regulation in human cervical and vaginal epithelial cells in vitro. Affymetrix microarray gene profiling revealed that inflammatory cytokine genes were prevalent among 317 known genes differentially expressed in immortalized ectocervical epithelial (Ect1) cells after incubation with pooled human seminal plasma. A dose- and time-dependent induction by seminal plasma of IL8, IL6, CSF2 and CCL2 mRNA expression in Ect1 cells was verified by quantitative RT-PCR. This was accompanied by increases in Ect1 secretion of immunoactive gene products IL-8, IL-6, GM-CSF and MCP-1. Similar cytokine responses were elicited in primary ectocervical epithelial cells. Endocervical epithelial (End1) and vaginal epithelial (Vk2) cells were less responsive to seminal fluid, with induction of IL-8 and MCP-1, but not GM-CSF or IL-6. In a panel of 10 seminal plasma samples, considerable variation in inflammatory cytokine-inducing activity was evident. These experiments show that seminal plasma can elicit expression of a range of inflammatory cytokines and chemokines in reproductive tract epithelia, and implicate the ectocervix as the primary site of responsiveness, with gene-specific differences in the kinetics and site-restrictedness of the response. Seminal factor regulation of inflammatory cytokines in the cervical epithelium is implicated in controlling the immune response to seminal antigens, and defence against infectious agents introduced at intercourse.

268 citations


Journal ArticleDOI
TL;DR: It would be sensible to advise men to abstain from smoking to avoid decreased fecundity, and a positive dose-response relationship between smoking and testosterone, LH and the LH/free testosterone ratios is found.
Abstract: BACKGROUND: Previous studies suggest a deleterious effect of cigarette smoking on semen quality, but their results have not been consistent. We studied the association between current smoking and semen characteristics and hormonal levels in a large group of healthy men. METHODS: From 1987 to 2004, seven separate occupational or environmental semen quality studies were co-ordinated by our department. A total of 2562 men participated, each providing semen and blood sample and answering a questionnaire about lifestyle and factors related to health. Appropriate semen and smoking data were available for 2542 men. RESULTS: Adjusting for study, age and other covariates, we observed an inverse dose–response relation between smoking and semen volume, total sperm count and percentage motile sperm. Heavy smokers had a 19% lower sperm concentration than non-smokers. We found a positive dose–response relationship between smoking and testosterone, LH and the LH/free testosterone ratios. CONCLUSION: Current smoking in adult life moderately impairs the semen quality. It is well known that semen quality is associated to fecundity. Therefore, it would be sensible to advise men to abstain from smoking to avoid decreased fecundity.

253 citations


Journal ArticleDOI
TL;DR: Insight into the molecular basis of seminal fluid signaling in the female reproductive tract may inform new interventions and management practices to ensure maximal fertility and reduce embryo mortality in pigs and, potentially, other livestock species.
Abstract: Seminal fluid contains potent signaling agents that influence female reproductive physiology to improve the chances of conception and pregnancy success. Cytokines and prostaglandins synthesized in the male accessory glands are transferred to the female at insemination, where they bind to receptors on target cells in the cervix and uterus, activating changes in gene expression that lead to modifications in structure and function of the female tissues. The consequences are increased sperm survival and fertilization rates, conditioning of the female immune response to tolerate semen and the conceptus, and molecular and cellular changes in the endometrium that facilitate embryo development and implantation. Male-female tract signaling occurs in rodents, livestock animals, and all other mammals examined thus far, including humans. In mice, the key signaling moieties in seminal plasma are identified as members of the transforming growth factor-beta family. Recent studies indicate a similar signaling function for boar factors in the pig, whereby the sperm and plasma fractions of seminal fluid appear to synergize in activating an inflammatory response and downstream changes in the female tract after insemination. Seminal plasma elicits endometrial changes, with induction of proinflammatory cytokines and cyclooxygenase-2, causing recruitment of macrophages and dendritic cells. Sperm contribute by interacting with seminal plasma factors to modulate neutrophil influx into the luminal cavity. The cascade of changes in local leukocyte populations and cytokine synthesis persists throughout the preimplantation period. Exposure to seminal fluid alters the dynamics of preimplantation embryo development, with an increase in the number of fertilized oocytes attaining the viable blastocyst stage. There is also evidence that seminal factors influence the timing of ovulation, corpus luteum development, and progesterone synthesis. Insight into the molecular basis of seminal fluid signaling in the female reproductive tract may inform new interventions and management practices to ensure maximal fertility and reduce embryo mortality in pigs and, potentially, other livestock species.

250 citations


Journal ArticleDOI
TL;DR: Sperm DNA fragmentation measured 2 to 5 months before the assisted reproduction procedure was a prognostic indicator of the fertilization, pregnancy, and miscarriage rates and the pregnancy outcome.

245 citations


Journal ArticleDOI
TL;DR: The DNA of STI pathogens was detected in semen from a high percentage of asymptomatic male infertility patients, and was associated with poor semen quality, and efforts to diagnose and treat subclinical genital-tract infections should be intensified.

235 citations


Journal ArticleDOI
TL;DR: The observed significant synergistic effect of BPb and blood cadmium on increasing serum testosterone, and additive effect of a decrease in serum selenium on Increasing serumosterone, may have implications on the initiation and development of prostate cancer because testosterone augments the progress of prostatecancer in its early stages.

214 citations


Journal ArticleDOI
TL;DR: In HA-selected spermatozoa the frequency of chromosomal disomy and diploidy is reduced 4- to 6-fold compared with semen sperm fractions, similar to the increase in numerical chromosomal aberrations in ICSI children.
Abstract: The testis-expressed chaperone protein, HspA2 (previously creatine kinase M isoform) was established as a measure of human sperm cellular maturity, function and fertility. The presence of HspA2 in the synaptonemal complex is likely to link low HspA2 expression and increased frequency of chromosomal aneuploidies in arrested-maturity spermatozoa. A relationship also exists between HspA2 expression in elongating spermatids and the associated spermatogenetic events, including plasma membrane remodelling and the formation of zona pellucida and hyaluronic acid (HA) binding sites. The HA receptor of mature spermatozoa, when coupled with HA-coated slides and/or Petri dishes, allows visual observation of sperm–HA binding, providing a basis for sperm maturity testing, a major improvement in semen evaluation, and selection of mature spermatozoa for intracytoplasmic sperm injection (ICSI). Thus, in HA-selected spermatozoa the frequency of chromosomal disomy and diploidy is reduced 4- to 6-fold compared with semen sperm fractions. This reduction is similar to the increase in numerical chromosomal aberrations in ICSI children. Combined studies of sperm shape and chromosome probes demonstrated that sperm morphology does not aid selection of haploid spermatozoa. The HA-mediated sperm selection is a novel and efficient technique that may alleviate potential problems related to ICSI fertilization with visually selected spermatozoa.

208 citations


Journal ArticleDOI
TL;DR: The results of this study provide a new approach to the cryopreservation of sperm from rams and related breeds, and thereby contribute to the improvement of these breeds for the world sheep industry.
Abstract: Uysal O., M. N. Bucak: Effects of Oxidized Glutathione, Bovine Serum Albumin, Cysteine and Lycopene on the Quality of Frozen-Thawed Ram Semen. Acta Vet. Brno 2007, 76: 383-390. Free radicals are known to be involved in lipid peroxidation as well as DNA and sperm membrane damages that may lead to decreased sperm motility or cell death. The balance between free radical production and their detoxifi cation may be an important factor in sperm survival and function before, during and after cryopreservation. The aim of this study was to determine the effects of the addition of the antioxidants of oxidized glutathione (GSSG), bovine serum albumin (BSA), cysteine and lycopene to freezing media on the post-thawing sperm characteristics, including motility, morphology, acrosome integrity, viability and membrane integrity. A total number of 42 ejaculates were collected using the artifi cial vagina from 4 Akkaraman rams and 10 replicates of the ejaculates were diluted with a Tris-based extender containing additives and no additives as control. GSSG (5 mM), BSA (20 mg/ml), cysteine (10 mM) and lycopene (800 μg) showed more positive effects than other concentrations of the supplements and controls in protecting sperm characteristics after the freezing-thawing process (P < 0.001). Many aspects of sperm protection, e.g. sperm motility, viability and membrane stabilisation of the sperm cells during relative cryopreservation, are the key factors in determining the preservation of sperm function. The results of this study provide a new approach to the cryopreservation of sperm from rams and related breeds, and thereby contribute to the improvement of these breeds for the world sheep industry. Antioxidants, ram semen, freezing, extender

187 citations


Journal ArticleDOI
TL;DR: Cryopreservation and H2O2 promote DNA instability in ram sperm, though motility is a more sensitive indicator of oxidative stress than the other parameters investigated.
Abstract: Assisted reproduction using frozen-thawed semen has practical advantages, although cryopreservation is detrimental to sperm fertility in most mammals We examined the influence of cryopreservation and reactive oxygen species (ROS) on ram sperm DNA stability (using SCSA), lipid peroxidation (LPO), chlortetracycline fluorescence (CTC) patterns, motility and viability In Experiment 1, DNA integrity, LPO, CTC, motility and viability tests were performed on fresh and cryopreserved sperm after 0, 6, and 24 hr in synthetic oviductal fluid (SOF) In Experiment 2, fresh sperm were incubated in serum-free SOF (SOF-S; 1, 4, and 24 hr) with 0, 50, 150, or 300 microM H2O2 then assayed Cryopreservation increased the percentage of sperm with a high DNA fragmentation index (%DFI), decreased the percentages of motile and viable sperm at thawing (0 hr), but did not affect LPO H2O2 (150 or 300 microM) increased %DFI after 24 hr LPO or sperm viability were not affected by H2O2, although most motility parameters decreased H2O2 decreased the percentage of chlortetracycline pattern F sperm at 4 hr and increased the percentage of acrosome-reacted sperm (pattern AR) after 1 hr Pooled data of Experiment 2 showed LPO was positively correlated with SCSA (r = 029 to r = 059; P < 005 to P < 001), while most motility parameters and the percentage of viable sperm were negatively correlated with LPO (r = -030 to r = -038; P < 005 to P < 001) LPO was positively correlated with the percentage of pattern AR sperm (r = 033; P < 001) Cryopreservation and H2O2 promote DNA instability in ram sperm, though motility is a more sensitive indicator of oxidative stress than the other parameters investigated

Journal ArticleDOI
01 Jan 2007
TL;DR: Fertility after AI of ruminant semen may be improved if the role of seminal plasma proteins and their effect, if added individually or in combination to spermatozoa at different stages of preservation, or other manipulations such as flow cytometric sorting, can be determined.
Abstract: The components of ruminant seminal plasma and their influence on the fertility of spermatozoa are reviewed. Seminal plasma can both inhibit and stimulate sperm function and fertility through the multifunctional actions of organic and inorganic components. These effects are now better understood because the composition of the seminal plasma, including its protein content and that of other structures, specifically membrane vesicles, has been clarified. Spermatozoa gain motility and fertilizing capacity as they transit the epididymis under the influence of factors produced by that organ. At ejaculation, inhibitory (termed "decapacitation") factors, sourced from the accessory sex glands, bind to the sperm surface. The major proteins isolated and characterised in ram seminal plasma, whose specific functions are yet to be determined, originate from the vesicular gland and comprise a spermadhesin together with proteins with fibronectin-II domains. In vitro handling of spermatozoa in preparation for artificial insemination (AI), involving processes such as dilution, cooling, freezing, re-warming and sperm sexing by flow cytometric sorting, can remove seminal plasma and may modify the proteins bound to the sperm surface. This destabilises the membranes and may pre-capacitate the spermatozoa, shortening their fertilizing lifespan. These changes may be reversible by seminal plasma fractions but responses differ depending on the type of sperm pre-treatment. Fertility after AI of ruminant semen may be improved if the role of seminal plasma proteins and their effect, if added individually or in combination to spermatozoa at different stages of preservation, or other manipulations such as flow cytometric sorting, can be determined.

Journal ArticleDOI
TL;DR: Assessment of sperm DNA damage appears to be a potential tool for evaluating semen samples prior to their use in assisted reproduction, helping to select spermatozoa with intact DNA or with the least amount of DNA damage for use inassisted conception.
Abstract: Many studies have shown how a 'paternal effect' can cause repeated assisted reproduction failures. In particular, with increasing experience of intracytoplasmic sperm injection (ICSI), it became evident that spermatozoa from some patients repeatedly fail to form viable embryos, although they can fertilize the oocyte and trigger early preimplantation development. Many authors have shown how this paternal effect can be traced back to anomalies in sperm chromatin organization: the spermatozoa of subfertile men are characterized by numerical abnormalities in spermatozoal chromosome content, Y chromosome microdeletions, alterations in the epigenetic regulation of paternal genome and non-specific DNA strand breaks. In particular, pathologically increased sperm DNA fragmentation is one of the main paternal-derived causes of repeated assisted reproduction failures in the ICSI era. The intention of this review is to describe nuclear sperm DNA damage, with emphasis on its clinical significance and its relationship with male infertility. Assessment of sperm DNA damage appears to be a potential tool for evaluating semen samples prior to their use in assisted reproduction, helping to select spermatozoa with intact DNA or with the least amount of DNA damage for use in assisted conception.

Journal ArticleDOI
TL;DR: The validation of a sperm DNA fragmentation test based on the sperm chromatin dispersion test (SCD) for stallion spermatozoa and on its application to semen that was chilled or frozen-thawed is reported on.

Journal ArticleDOI
TL;DR: Non-apoptotic sperm fractions have morphologically superior quality sperm compared with apoptotic fractions as reflected by significantly lower SDI scores, which may support abortive apoptosis, where the apoptotic mechanism of sperm is already triggered prior to ejaculation.
Abstract: BACKGROUND: This study aimed to assess the relationship between apoptosis in human ejaculated spermatozoa, sperm morphology and the novel sperm deformity index (SDI). METHODS: Semen specimens from 50 healthy donors were prepared by density-gradient centrifugation followed by incubating the prepared sperm with paramagnetic annexin V-conjugated microbeads and subjecting this to magnetic cell sorting (MACS). The procedure delivers two sperm fractions: annexin-negative (non-apoptotic) and annexin-positive (apoptotic). Activated caspase-3 levels and the integrity of the sperm mitochondrial membrane potential (MMP) were assessed as markers of apoptosis in the annexin-negative and -positive aliquots following MACS. Sperm morphology and the SDI scores were assessed using the strict criteria. RESULTS: Compared with the apoptotic sperm subpopulations, the non-apoptotic sperm subpopulations had an improved sperm morphology profile as demonstrated by significantly higher proportions of sperm with normal morphology and significantly lower SDI scores and percentages of sperm with acrosomal defects, midpiece defects, cytoplasmic droplet and tail defects. There was a significant correlation between sperm morphology attributes studied and the expressed apoptotic markers—caspase-3 activation and MMP integrity. CONCLUSIONS: Non-apoptotic sperm fractions have morphologically superior quality sperm compared with apoptotic fractions as reflected by significantly lower SDI scores. The study results may support abortive apoptosis, where the apoptotic mechanism of sperm is already triggered prior to ejaculation.

Journal ArticleDOI
TL;DR: The aim of this study was to determine the effects of the addition of the anti-oxidants taurine and glutathione, and the membrane structure stabiliser, trehalose, on sperm viability during low temperature liquid storage.

Journal ArticleDOI
TL;DR: Findings could be partially ascribed to the high GSH level contained in the commercial extender which seem able to alleviate oxidative damages to spermatozoa surviving freezing thawing procedures.

Journal ArticleDOI
TL;DR: It is demonstrated that a febrile episode can have marked effects on semen parameters and sperm DNA integrity and is particularly important for the counseling of infertile couples and in relation to assisted reproductive techniques (ART).

Journal ArticleDOI
TL;DR: The results indicate that prenatal exposure to tobacco smoke may have an adverse effect on semen quality and, if these associations are causal, they could explain some of the reported differences between populations and secular changes in semen quality.
Abstract: A few studies indicate that exposure to maternal smoking during fetal life decreases semen quality in adult life, but the results are inconsistent and retrospectively collected smoking data were used in most studies. From a Danish pregnancy cohort established in 1984-1987, 347 of 5,109 sons were selected according to their exposure to tobacco smoke in fetal life. From February 2005 to January 2006, a semen sample from the 347 men was analyzed for conventional semen characteristics according to standardized criteria by using a mobile laboratory. The authors found an inverse association between maternal smoking during pregnancy and total sperm count (p = 0.002). Men exposed to more than 19 cigarettes daily during pregnancy had approximately 19% lower semen volume (p = 0.04), 38% lower total sperm count (p = 0.11), and 17% lower sperm concentration (p = 0.47) compared with unexposed men. The odds ratio for oligospermia was 2.16 (95% confidence interval: 0.68, 6.87) among exposed men compared with the unexposed. No associations were found for sperm motility or morphology. These results indicate that prenatal exposure to tobacco smoke may have an adverse effect on semen quality and, if these associations are causal, they could explain some of the reported differences between populations and secular changes in semen quality.

Journal ArticleDOI
TL;DR: A statistically significant and inverse relationship was observed between semen volume, sperm quality and patient age, in spite of prolonged sexual abstinence duration.
Abstract: This study evaluates retrospectively the relationship between age and semen parameters among men with normal sperm concentration. It was based on computerized data and performed in an Academic Fertility and IVF Unit. Six thousand and twenty-two semen samples with sperm concentrations of >or=20 x 10(6) ml(-1) were examined according to WHO criteria and analysed in relation to patients' age. For each age group, mean values +/- SD of semen volume, sperm concentration, percentage of motile spermatozoa, normal morphology, acrosome index, total sperm count/ejaculate, total motile sperm count/ejaculate and sexual abstinence duration were examined. A peak semen volume of 3.51 +/- 1.76 ml(-1) was observed at age >or=30 to or=55 years (P or=55 years (P or=30 to 55 years. A statistically significant and inverse relationship was observed between semen volume, sperm quality and patient age, in spite of prolonged sexual abstinence duration. Top sperm parameters were observed at age >or=30 to <35 years, while the most significant reduction in sperm parameters occurred after the age of 55 years.

Journal ArticleDOI
TL;DR: In the fertile population, ROSs were positively correlated with leukocytes and negatively correlated with sperm count and motility and concentration and Seminal leukocyte levels below 1 x 10(6)/mL were associated with increased ROSs.
Abstract: Although reactive oxygen species (ROSs) are clearly implicated in the pathogenesis of male infertility, few studies have attempted to define the basal levels of ROSs in fertile men. Levels of ROSs are highly influenced by the presence of leukocytes and are associated with decreased seminal parameters. The objective of our study was to determine the normal ROS reference values in neat and washed semen of a fertile population and to correlate the leukocyte concentrations with seminal parameters. We evaluated 114 fertile men seeking vasectomy and 47 subfertile patients as a positive control. All samples were subjected to semen analysis and Endtz testing; chemiluminescence assay was used to determine ROS levels. All seminal parameters were significantly higher in the fertile men than in the subfertile patients. In nonleukocytospermic samples, ROS levels were lower in the fertile men than in the subfertile patients in neat (0.29 [0.18, 0.54] vs 0.94 [0.38, 1.51]) (P = .001) and washed semen (5.73 [1.90, 14.71] vs 23.4 [9.46, 115.55]) (P = .001). Similarly, in samples with leukocytes (Entdz, less than 1 x 10(6)/mL), ROS levels were lower in the fertile men in neat (0.75 [0.27, 1.71] vs 2.0 [0.97, 27.41]) (P = .001) and washed semen (15.85 [4.18, 62.16] vs 239.83 [33.4, 1193.75]) (P < .0001). As expected, samples with leukocytes had significantly higher ROS values in washed and neat semen. In the fertile population, ROSs were positively correlated with leukocytes and negatively correlated with sperm count and motility. In semen samples without leukocytes, the normality cutoff of ROSs was 0.55 x 10(4) counted photons per minute with 76.4% area under the curve (AUC) in the neat samples and 10.0 x 10(4) counted photons per minute with 77% AUC in the washed samples. In semen samples with leukocytes, the cutoff for ROSs in neat samples was 1.25 with 72.7% AUC and 51.5 with 81% AUC in the washed samples. We defined the cutoff levels of ROSs in a fertile population. Seminal leukocyte levels below 1 x 10(6)/mL were associated with increased ROSs. ROS levels were positively correlated with leukocytes and negatively correlated with sperm motility and concentration. Patients with normal seminal parameters and lower seminal leukocyte levels may benefit from therapeutic interventions that improve semen quality.

Journal ArticleDOI
TL;DR: The addition of SP from good sperm freezers improved the motility and viability of thawed spermatozoa without any influence on MDA production and increased the percentage of penetrated (SP3) and polyspermic oocytes (SP4) with respect to the control.
Abstract: The study evaluated the protective effect of seminal plasma (SP) added to freezing extender against cryopreservation injuries to boar spermatozoa. Pooled sperm-rich fractions collected from 9 fertile boars were frozen in 0.5-mL straws after being extended in a conventional freezing extender either alone or supplemented with 5% of SPs (SP1-SP4) collected from the sperm-rich fractions (diluted 1:1, vol/vol, in Beltsville Thawing Solution extender) from 4 boars (1-4) with known sperm cryosurvival (poor, moderate, and good sperm freezers). Cryopreservation injuries were assessed in terms of postthaw sperm motility (assessed by computer-assisted sperm analysis), viability (plasma membrane and acrosome integrity assessed simultaneously by flow cytometry), membrane lipid peroxidation (malondialdehyde [MDA] production), and the ability of thawed spermatozoa to fertilize in vitro-matured homologous oocytes. The addition of SP from good sperm freezers (SP3 and SP4) improved (P < .01) the motility and viability of thawed spermatozoa without any influence on MDA production. Moreover, SP from good sperm freezers also increased (P < .05) the percentage of penetrated (SP3) and polyspermic oocytes (SP4) with respect to the control. Neither the total amount of SP proteins, protein profiles, nor antioxidant capacity of the different SPs were related to the various cryosurvival/fertilizing capacities of the processed spermatozoa.

Journal ArticleDOI
TL;DR: It is suggested that timely morphological changes in the female reproductive tract, possibly muscular in nature, may be needed for successful sperm storage, and that Acps from the male are needed in order for these changes to occur.

Journal ArticleDOI
TL;DR: Experimental evidence demonstrates that prostate-specific antigen (PSA) rapidly cleaves Sg, an event temporally associated with semen liquefaction and initiation of sperm motility, which could play important role in preventing premature capacitation.
Abstract: Semenogelin (Sg), the main component of the human semen coagulum, is an important and versatile protein acting on several sperm parameters, both as intact or degraded Sg. Sg originates mostly from seminal vesicle and probably is responsible for sperm immobilization in the seminal coagulum. Purified Sg can be cross-linked by transglutaminase or phosphorylated by kinases, but the actual occurrence of these reactions in reproductive physiology is not clear. Experimental evidence demonstrates that prostate-specific antigen (PSA) rapidly cleaves Sg, an event temporally associated with semen liquefaction and initiation of sperm motility. Sg and its degradation peptides participate in various processes including Zn +2 shuttling, antibacterial activity, hyaluronidase activation, and so on. Sg inhibits sperm motility at the concentration found in the coagulum, but the rapid processing by PSA allows initiation of movement. The mechanism of Sg action and its targets are not known, but improper Sg degradation decreases fertility. Sg and its degradation peptides block sperm capacitation and associated events at concentrations much lower than those of seminal plasma and could play important role in preventing premature capacitation. The effects of Sg are dependent on time and proteolysis due to PSA, and any imbalance may affect sperm physiology and fertility.

Journal ArticleDOI
TL;DR: Wang et al. as mentioned in this paper examined whether reproductive hormones play a role in the association between body mass index (BMI) and semen quality and found that low BMI was associated with reduced semen quality.
Abstract: Aim: To examine whether reproductive hormones play a role in the association between body mass index (BMI) and semen quality. Methods: Semen quality and testosterone (T), luteinizing hormone (LH), follicle-stimulating hormone (FSH) and estradiol (E2) were evaluated in 990 fertile males with age 38.9 ± 9.7 (mean ± SD) years recruited from the Chinese general population in 2001 and 2002. Results: Semen quality was reduced among underweight (BMI < 18.5) compared with normal (BMI 18.5–24.9) and overweight (BMI 25.0–29.9), but the associations were independent of reproductive hormones. After adjustment for the potential confounders, underweight men had reductions in sperm concentration (22.4 × 10 6 /mL), total sperm count (52.9 × 10 6 ) and percentage of normal sperm forms (6.9%) compared with men with normal BMI. Being underweight may be a risk factor for low sperm concentration (OR: 4.68, 95% confidence intervals [CI]: 2.01–10.91). Otherwise, being overweight may be a protected factor for low sperm concentration (OR: 0.25; 95% CI: 0.08–0.83) and low total sperm count (OR: 0.37, 95% CI: 0.15–0.87). Conclusion: Low BMI was associated with reduced semen quality. The associations between BMI and semen quality were found statistically significant even after adjustment for reproductive hormones. Reproductive hormones cannot explain the association between BMI and semen quality. (Asian J Androl 2007 Nov; 9: 827–834)

Journal ArticleDOI
TL;DR: The presence of RAGE implies that it may play a central role in sperm nDNA damage particularly in diabetic men where the levels are elevated.
Abstract: BACKGROUND: Diabetics have a significantly higher percentage of sperm with nuclear DNA (nDNA) fragmentation and increased levels of advanced glycation end products (AGEs), in their testis, epididymis and sperm. As the receptor for AGEs (RAGE) is important to oxidative stress and cell dysfunction, we hypothesise, that it may be involved in sperm nDNA damage. METHODS: Immunohistochemistry was performed to determine the presence of RAGE in the human testis and epididymis. A comparison of the receptor's incidence and localization on sperm from 10 diabetic and 11 non-diabetic men was conducted by blind semi-quantitative assessment of the immunostaining. Enzyme-linked immunosorbent assay analysis ascertained RAGE levels in seminal plasma and sperm from 21 diabetic and 31 non-diabetic subjects. Dual labelling immunolocalization was employed to evaluate RAGE's precise location on the sperm head. RESULTS: RAGE was found throughout the testis, caput epididymis, particularly the principle cells apical region, and on sperm acrosomes. The number of sperm displaying RAGE and the overall protein amount found in sperm and seminal plasma were significantly higher in samples from diabetic men (P < 0.01, P < 0.0001 and P < 0.0001, respectively). CONCLUSIONS: The presence of RAGE implies that it may play a central role in sperm nDNA damage particularly in diabetic men where the levels are elevated.

Journal ArticleDOI
TL;DR: The future need for semen cryopreservation programmes will focus mainly on improvement of predictors of male suitability for semen freezing, emergence of standardized methods of semen freezing in species other than chicken and increasing development of avian cryobanks.
Abstract: Semen cryopreservation in domestic birds has been studied extensively in the past fifty years. However, efficient methods to freeze semen of chicken of different breeds have emerged only in the las...

01 Jan 2007
TL;DR: BSP proteins in seminal plasma act like a double-edged sword, being both beneficial and detrimental to sperm, and low-density lipoproteins present in egg yolk appear to abolish the detrimental effect of BSP proteins on the sperm membrane.
Abstract: Seminal plasma contains factors that are beneficial and/or detrimental to sperm function and/or storage. However, the nature and characteristics of these factors are not well understood. The major protein fraction (50-70%) of bovine seminal plasma is represented by a family of phospholipid-binding proteins collectively called BSP proteins. The BSP protein signature is characterised by two tandemly repeated fibronectin type 2 (Fn2) domains. It is now well established that BSP proteins and their relatives represent a new emerging superfamily of proteins in mammals. They bind to sperm membrane choline phospholipids at ejaculation. They also bind to capacitation factors, namely, high-density lipoproteins and glycosaminoglycans and promote sperm capacitation induced by these molecules, indicating their beneficial role in sperm function and fertility. In contrast, BSP proteins also induce changes in the sperm plasma membrane by stimulating cholesterol and phospholipid efflux. Thus, the continuous exposure of sperm to seminal plasma that contains BSP proteins is detrimental to the sperm membrane, which may render the membrane very sensitive to sperm storage in the liquid or frozen states. Interestingly, BSP proteins specifically bind low-density lipoproteins present in egg yolk, a compound commonly used in semen extenders. This interaction appears to abolish the detrimental effect of BSP proteins on the sperm membrane. Therefore, BSP proteins in seminal plasma act like a double-edged sword, being both beneficial and detrimental to sperm.

Journal ArticleDOI
TL;DR: The present review focuses on Bos taurus, because more is known about this species than others and it is known that at coitus, bull spermatozoa are deposited into the anterior vagina, where they rapidly enter the cervix.
Abstract: Artificial insemination with sexed semen, in vitro fertilisation and intracytoplasmic sperm injection have been used to reproduce animals, but often not as successfully as natural mating. Learning more about how spermatozoa normally interact with the female tract can provide inspiration for developing improvements in assisted reproduction. The present review focuses on Bos taurus, because more is known about this species than others. At coitus, bull spermatozoa are deposited into the anterior vagina, where they rapidly enter the cervix. Cervical mucus quickly filters out seminal plasma from spermatozoa, unlike most assisted reproduction protocols. Spermatozoa that reach the uterus may require certain cell surface proteins to swim through the uterotubal junction. Shortly after passing through the junction, most spermatozoa are trapped in a storage reservoir by binding to oviducal epithelium, in the case of cattle via bovine seminal plasma (BSP) proteins coating the sperm head. As ovulation approaches, spermatozoa capacitate and shed BSP proteins. This reduces sperm binding to the epithelium and releases them from storage. Motility hyperactivation assists spermatozoa in leaving the storage reservoir, swimming through oviducal mucus and the cumulus oophorus, and penetrating the oocyte zona pellucida. Chemotactically regulated switching between asymmetrical (i.e. hyperactivated) and symmetrical flagellar beating may also guide spermatozoa to the oocyte.

Journal ArticleDOI
TL;DR: TUNEL assay clearly demonstrates an increase in sperm DNA damage with age, which is significantly lower in Group I than in Group II or III and regression analysis demonstrated a significant increase in semen DFI with age.
Abstract: The objective was to investigate the influence of age on sperm DNA damage. Semen samples were collected from 508 men in an unselected group of couples attending infertility investigation and treatment. DNA fragmentation in spermatozoa was measured by TdT (terminal deoxynucleotidyl transferase)-mediated dUTP nick-end labelling (TUNEL) assay; at least 200 spermatozoa in randomly selected areas of microscope slides were evaluated using a fluorescent microscope and the percentage of TUNEL positive spermatozoa was determined. The number of cells with red fluorescence (TUNEL positive) was expressed as a percentage of the total sample [DNA fragmentation index (DFI)]. Age was treated as a continuous variable for regression and correlation analysis. The following male age groups were used: Group I: ≤35 years, Group II: 36–39 years, and Group III: ≥40 years. DFI was significantly lower in Group I than in Group II (P = 0.034) or III (P = 0.022). There was no difference in DFI between Groups II and III. In addition, regression analysis demonstrated a significant increase in sperm DFI with age (P = 0.02). TUNEL assay clearly demonstrates an increase in sperm DNA damage with age.