Relationship between seminal plasma zinc concentration and spermatozoa-zona pellucida binding and the ZP-induced acrosome reaction in subfertile men

The aim of this study was to determine the relationship between seminal zinc concentration and spermatozoazona pellucida （ZP） binding and the ZP-induced acrosome reaction （ZPIAR） in subfertile men. Semen analyses and seminal zinc concentration assessments were carried out according to the World Health Organization manual for 458 subfertile men. A spermatozoa-ZP interaction test was carried out by incubating 2 × 10^6 motile spermatozoa with a group of four unfertilized oocytes obtained from a clinical in vitro fertilization programme. After 2 h of incubation, the number of spermatozoa bound per ZP and the ZPIAR of ZP-bound spermatozoa were examined. The effect of adding 0.5 mmol L^-1 zinc to the media on the ZPIAR of spermatozoa from normozoospermic men was also tested in vitro. Seminal zinc concentration positively correlated with sperm count and duration of abstinence, but negatively correlated with semen volume. On analysis of data from all participants, both spermatozoa-ZP binding and the ZPI- AR were significantly correlated with sperm motility and normal morphology, but not with seminal zinc concentration. However, in men with normozoospermic semen, the seminal zinc concentration was significantly higher in men with defective ZPIAR （ 〈 16%） than in those with normal ZPIAR （ ≥ 16% ） （P 〈 0.01）. The addition of 0.5 mmol L^-1 zinc to the culture media had no effect on spermatozoa-ZP binding, but significantly reduced the ZPIAR in vitro （P 〈 0. 001）. In conclusion, seminal zinc concentration is correlated with sperm count and the duration of abstinence in subfertile men. In men with normozoospermic semen, high seminal zinc concentration may have an adverse effect on the ZPIAR.

Seminal plasma anti-Müllerian hormone level correlates with semen parameters but does not predict success of testicular sperm extraction （TESE）

Aim： To assess seminal plasma anti-Müllerian hormone （AMH） level relationships in fertile and infertile males. Methods： Eighty-four male cases were studied and divided into four groups： fertile normozoospermia （n = 16）, oligoastheno- teratozoospermia （n = 15）, obstructive azoospermia （OA） （n = 13） and non-obstructive azoospermia （NOA） （n = 40）. Conventional semen analysis was done for all cases. Testicular biopsy was done with histopathology and fresh tissue examination for testicular sperm extraction （TESE） in NOA cases. NOA group was subdivided according to TESE results into unsuccessful TESE （n = 19） and successful TESE （n = 21）. Seminal plasma AMH was estimated by enzyme linked immunosorbent assay （ELISA） and serum follicular stimulating hormone （FSH） was estimated in NOA cases only by radioimmunoassay （RIA）. Results： Mean seminal AMH was significantly higher in fertile group than in oligoasthenoteratozoospermia with significance （41.5±10.9 pmol/L vs. 30.5±10.3 pmol/L, P 〈 0.05）. Seminal AMH was not detected in any OA patients. Seminal AMH wascorrelated positively with testicular volume （r = 0.329, P = 0.005）, sperm count （r = 0.483, P = 0.007）, sperm motility percent （r = 0.419, P = 0.021） and negatively with sperm abnormal forms percent （r = -0.413, p = 0.023）. Nonsignificant correlation was evident with age （r = -0.155, P = 0.414） and plasma FSH （ r = -0.014, P = 0.943）. In NOA cases, seminal AMH was detectable in 23/40 cases, 14 of them were successful TESE （57.5%） and was undetectable in 17/40 cases, 10 of them were unsuccessful TESE （58.2%）. Conclusion： Seminal plasma AMH is an absolute testicular marker being absent in all OA cases. However, seminal AMH has a poor predictability for successful testicular sperm retrieval in NOA cases.

Proteomic analysis of seminal plasma from asthenozoospermia patients reveals proteins that affect oxidative stress responses and semen quality

Asthenozoospermia （AS） is a common cause of human male infertility. In one study, more than 80% of the samples from infertile men had reduced sperm motility. Seminal plasma is a mixture of secretions from the testis, epididymis and several male accessory glands, including the prostate, seminal vesicles and Cowper＇s gland. Studies have shown that seminal plasma contains proteins that are important for sperm motility. To further explore the pathophysiological character of AS, we separated the seminal plasma proteins from AS patients and healthy donors using sodium dodecyl sulfate polyacrylamide gel electrophoresis and in-gel digestion, and then subjected the proteins to liquid chromatography-mass spectrometry （LC-MS/MS） analysis. A total of 741 proteins were identified in the seminal plasma, with a false discovery rate of 3.3%. Using spectral counting, we found that 45 proteins were threefold upregulated and 56 proteins were threefold downregulated in the AS group when compared with the control. Most of these proteins originated from the epididymis and prostate. This study identified a rich source of biomarker candidates for male infertility and indicates that functional abnormalities of the epididymis and prostate can contribute to AS. We identified D J-1--a protein that has been shown elsewhere to be involved in the control of oxidative stress （OS）-as a downregulated protein in AS seminal plasma. The levels of D J-1 in AS seminal plasma were about half of those in the control samples. In addition, the levels of reactive oxygen species were 3.3-fold higher in the AS samples than in the controls. Taken together, these data suggest that downregulation of DJ-1 is involved in OS in semen, and therefore affects the quality of the semen.

Quick recovery and characterization of cell-free DNA in seminal plasma of normozoospermia and azoospermia： implications for non-invasive genetic utilities

We established a quick and reliable method for recovering cell-free seminal DNA （cfsDNA）, by using the binding-washing-elution procedure on the DNA purification column. Low variations （below 15%） among the triplicate values of cfsDNA quantity verified the reproducibility of our cfsDNA recovery method. Similar cfsDNA yield and size distribution between seminal plasma acquired by filtration and centrifugation confirmed the presence of cfsDNA. To investigate the general characterization of cfsDNA, the quantitation and size distribution of cfsDNA from normozoospermic and azoospermic semen were analyzed by real-time PCR and electrophoresis, respectively. CfsDNA concentration in semen with normozoospermia （n = 11） was 1.34 ± 0.65 μg ·mL^-1, whereas a higher cfsDNA concentration was observed in azoospermia （2.56 ± 1.43 μg ·mL^-1, n = 9）. The continuous distribution of DNA fragments ranging from -1 kb to 15 kb and a spectrum of multiples of 180-bp fragments were observed in each normozoospermic and azoospermic sample. Distinct characteristic DNA ladder fragmentations in some azoospermic samples implicated that cfsDNA originate partly from apoptotic cells. CfsDNAs of 36 selected azoospermic patients with known information of Y chromosome microdeletion were subjected to the same microdeletion analysis by multiplex PCR and PCR amplification of sY114 （1 450 bp）. All multiplex PCR reactions with cfsDNA amplified successfully and provided the same result as leukocyte DNA. PCR amplification of sY114 gave a 1 450-bp amplicon as expected. Our data suggested the potential use of cfsDNA in search of biomarker or diagnostic procedures.

Beta-endorphin in serum and seminal plasma in infertile men

Aim： To access beta-endorphin levels in serum as well as seminal plasma in different infertile male groups. Methods： Beta-endorphin was estimated in the serum and seminal plasma by enzyme-linked immunosorbent assay （ELISA） method in 80 infertile men equally divided into four groups： non-obstructive azoospermia （NOA）, obstructive azoospermia （OA）, congenital bilateral absent vas deferens （CBVAD） and asthenozoospermia. The results were compared to those of 20 normozoospermic proven fertile men. Results： There was a decrease in the mean levels of betaendorphin in the seminal plasma of all successive infertile groups （mean ± SD： NOA 51.30 ± 27.37, OA 51.88 ± 9.47, CBAVD 20.36 ± 13.39, asthenozoospermia 49.26 ± 12.49 pg/mL, respectively） compared to the normozoospermic fertile control （87.23 ± 29.55 pg/mL）. This relation was not present in mean serum level of beta-endorphin between four infertile groups （51.09 ± 14.71, 49.76 ± 12.4, 33.96 ± 7.2, 69.1 ± 16.57 pg/mL, respectively） and the fertile control group （49.26 ± 31.32 pg/mL）. The CBVAD group showed the lowest seminal plasma mean level of beta-endorphin. Testicular contribution of seminal beta-endorphin was estimated to be approximately 40%. Seminal beta-endorphin showed significant correlation with the sperm concentration （r = 0.699, P = 0.0188） and nonsignificant correlation with its serum level （r = 0.375, P = 0.185） or with the sperm motility percentage （r = 0.470, P = 0.899）. Conclusion： The estimation of beta-endorphin alone is not conclusive to evaluate male reproduction as there are many other opiates acting at the hypothalamic pituitary gonadal axis.

Evaluation of deoxyribonuclease activity in seminal plasmaof ejaculated chicken semen

Aim: To confirm the stability of exogenous genes in the generation of transgenic chickens using ejaculated chicken sperm, the deoxyribonuclease (DNase) activity was evaluated in the seminal plasma of ejaculated semen and the stability of DNA was examined by adding lipofection reagents. Methods: A PCR fragment (249 bp) of pEGFPN-1 vector was used as the DNA substrate and was incubated with the seminal plasma at 40 ℃ for 30 min. Then, the whole reaction solution was subjected to agarose gel electrophoresis and the DNA size was evaluated under UV light. Results: The DNA substrate was completely diminished after incubation with seminal plasma. However, the substrate was intact after incubation with heat-treated seminal plasma or incubation with seminal plasma in the presence of 0.5 mmol/L -5 mmol/L EDTA. The substrate was stabilized in the seminal plasma by the addition of commercially available lipofection reagents. Conclusion: The DNase activity is present in the seminal plasma of ejaculated chicken semen. However, DNA is stable in the liposomal-DNA complex.

Direct Determination of Trace Impurities in High Purity Zinc Oxide by High Resolution Inductively Coupled Plasma Mass Spectrometry

The determination of trace impurities in high purity zinc oxide by high resolution inductively coupled plasma mass spectrometry （ HR-ICP-MS ） was investigated. To overcome some poteutially problematic spectral iuterference, measurements were acquired in both middle and high resolution modes. The matrix effects due to the presence of excess HCl and zinc were evaluated. The optimum conditions for the determination were tested and discussed. The standard addition method was employed for quantitative analysis. The detection limits ranged from 0.02μg/ g to 6 μg/ g depending on the elements. The experimental resalts for the determination of Na, Mg, Ca, Cr, Mn, Fe, Co, Ni, Cu, Mo, Cd, Sb and Pb in several high purity zinc oxide powders were presented.

Oxytocin in pig seminal plasma is positively related with in vivo fertility of inseminated sows

Background:Identification of relevant in vivo biomarkers for fertility remains a challenge for the livestock industry.Concentrations of the small peptide hormone oxytocin(OXT),involved in male reproductive function and present in the seminal plasma(SP)of several species could be a robust one.This study characterized concentrations of SPOXT in ejaculates from boars used in artificial insemination(AI)programs aiming to evaluate its relationship with sperm quality variables and in vivo fertility of their liquid-stored AI-semen.Seminal OXT concentrations(ng/mL)were measured in 169 ejaculates from 61 boars of the Duroc,Pietrain,Landrace and Large White breeds using a direct competitive immunoassay test based on AlphaLISA®technology.Ejaculate(ejaculate volume,sperm concentration,total sperm count)and sperm parameters(motility,viability,intracellular generation of reactive oxygen species,plasma membrane fluidity)were assessed at 0 h and 72 h in AI-semen samples stored at 17℃.In vivo fertility included only 18 Large White and Landrace boars whose AI-semen was used to inseminated>100 sows and evaluated both farrowing rate and litter size of 3,167 sows.Results:The results showed that SP-OXT differed between boars and between ejaculates within boar(P<0.05)but not between breeds(Duroc,Pietrain,Landrace and Large White).Ejaculates with higher SP-OXT concentration/mL(hierarchically grouped;P<0.001)had larger volume and came from younger boars(P<0.05).Ejaculates of boars showing positive farrowing rate deviation exhibited higher(P<0.05)SP-OXT concentration/mL than those with negative farrowing rate deviation.Conclusion:The SP concentrations of OXT are boar,ejaculate and age dependent,and positively related with ejaculate volume and farrowing rates of liquid-stored semen AI-doses.

Molecular heterogeneity of gelatin-binding proteins from human seminal plasma

Defining the molecular characteristics of seminal plasma proteins is essential for understanding their function in physiological and pathological conditions. Starting from the predicted importance of human seminal plasma gelatin-binding proteins, comprising fibronectin （FN） and FN-related molecules, for male fertility, this study aims at gaining insight into their immuno-glycobiochemical properties. Human seminal plasma from subjects with normal semen parameters were separated on a gelatin-Sepharose column and analyzed by sodium dodecyl sulfate- polyacrylamide gel electrophoresis and immunoblotting using antibodies against distinct FN forms. Heterogeneity of the isolated molecular species was examined by protein chip arrays combined with surface-enhanced laser desorption/ionization time of flight mass spectrometry, on normal, metal and hydrophobic surfaces. Carbohydrate composition was investigated using mannose-, fucose- and sialic acid-specific plant lectins and galectin-1. The results obtained indicated a pattern of isolated proteins corresponding to that of known FN fragments, as confirmed by immunoreactivity. Among them heparin-binding ability was preferentially associated with low molecular mass species. As for posttranslational modifications, phosphorylation and glycosylation of distinct fragments were revealed. Lectin binding to fragments containing the gelatin-binding domain, particularly with Ricinus communis agglutinin I, was stronger than to fragments containing the cell-binding site of FN. A low level of sialylation and distinctive concanavalin A- and Lens culinaris agglutinin-reactive species were also observed. Galectin-1 did not interact with the isolated preparation. Resolving the molecular heterogeneity of normal human seminal plasma FN and gaining initial insight into possible similarities/differences with known FN molecular species may be considered a prerequisite step preceding challenging the clinical usefulness of these molecular properties.

Significance of malondialdehyde concentration in seminal plasma of infertile men

Objective: To determine the concentration of malondialdehyde (MDA), product of lipid peroxidation, in seminal plasma and evalu ate its significance. Methods: Ninety-three cases of infertile pa tients were divided into the obstructive azoospermic (12 cases), the non-obstructive azoospermic (15 cases), the oligozoospermic (21 cases), the asthenozoospermic (19 cases), the oligoastheno zoospermic (16 cases) and the oligoasthenoteratozoospermic (10) groups. Eighteen fertile males served as the controls. MDA con centration was assessed by high-performance liquid chromatogra phy (HPLC). Results: With the exception of the obstructive azoospermic group, the MDA concentration in the seminal plasma was significantly different between the control group and the infer tile groups (P<0.01) as well as between the different infertile groups. Conclusion: Determination of MDA concentration in the seminal plasma is helpful to the diagnosis of male infertility induced by overproduction of reactive oxygen species.

Assessment of seminal plasma laminin in fertile and infertile men

Aim： To assess laminin levels in the seminal plasma of infertile and fertile men, and to analyze the correlation of laminin levels with sperm count, age, sperm motility and semen volume. Methods： One hundred and twenty-five recruited men were equally divided into five groups according to their sperm concentration and clinical examination： fertile normozoospermia, oligoasthenozoospermia, non-obstructive azoospermia （NOA）, obstructive azoospermia （OA） and congenital bilateral absent vas deferens （CBAVD）. The patients＇ medical history was investigated and patients underwent clinical examination, conventional semen analysis and estimation of seminal plasma laminin by radioimmunoassay. Results： Seminal plasma laminin levels of successive groups were： 2.82 ± 0.62, 2.49 ± 0.44, 1.77 ± 0.56, 1.72 ± 0.76, 1.35 ± 0.63 U/mL, respectively. The fertile normozoospermic group showed the highest concentration compared to all infertile groups with significant differences compared to azoospermic groups （P 〈 0.05）. Testicular contribution was estimated to be approximately one-third of the seminal laminin. Seminal plasma laminin demonstrated significant correlation with sperm concentration （r = 0.460, P 〈 0.001） and nonsignificant correlation with age （r = 0.021, P = 0.940）, sperm motility percentage （r = 0.142, P = 0.615） and semen volume （r = 0.035, P = 0.087）. Conelusion： Seminal plasma laminin is derived mostly from prostatic and testicular portions and minimally from the seminal vesicle and vas deferens. Estimating seminal laminin alone is not conclusive in diagnosing different cases of male infertility.

Cytokines in Human Seminal Plasma and Their Effect on Male Fertility

Cytokines are a heterogeneous group of peptides that play an important role in intercellular communication, regulation of innate and specific immunity, hematopoiesis, interaction between the immune system and neuroendocrine network as well as in reproduction and development. Seminal plasma provides an immunological environ- ment for the semen and contains important biological response mediators. Numerous studies investigated the presence of various cytokines in the seminal plasma and tried to correlate cytokine levels with sperm quality and male fertility. However, the patho- physiological significance of seminal cytokines in sperm function is still not completely understood. The purpose of this review is to provide a brief summary of the extensive literature dealing with cytokines in the seminal plasma and to discuss the contribution of local cytokine immunity to male fertility.

Enhanced Work Function of Al-Doped Zinc-Oxide Thin Films by Oxygen Inductively Coupled Plasma Treatment

Al-doped zinc-oxide （AZO） thin films treated by oxygen and chlorine inductively coupled plasma （ICP） were compared. Kelvin probe （KP） and X-ray photoelectron spectroscopy （XPS） were employed to characterize the effect of treatment. The results of KP measurement show that the surface work function of AZO thin films can increase up to 5.92 eV after oxygen ICP （O-ICP）＇s treatment, which means that the work function was increased by at least 1.1 eV. However, after the treatment of chlorine ICP （CI-ICP）, the work function increased to 5.44 eV, and the increment was 0.6 eV. And 10 days later, the work function increment was still 0.4 eV after O-ICP＇s treatment, while the work function after Cl-ICP＇s treatment came back to the original value only after 48 hours. The XPS results suggested that the O-ICP treatment was more effective than CI-ICP for enhancing the work function of AZO films, which is well consistent with KP results.

Oxidants and Anti-Oxidants in Turbot Seminal Plasma and Their Effects on Sperm Quality

In this research, the concentration and activity of oxidants and anti-oxidants in turbot semen, and their effects on sperm quality were studied. The results showed that superoxide dismutase(SOD), catalase, glutathione reductase(GR), uric acid, vitamin E(VE) and vitamin C(VC) were more abundant in seminal plasma than in spermatozoa. The variation for each of them was specific. In seminal plasma, the activity of SOD and GR increased from November 15, November 30 to December 15, and then decreased on December 30. The concentrations of both VC and uric acid decreased during the first 3 sampling times and increased on December 30. The oxidants in seminal plasma accumulated to the highest on December 30. Lactic acid(LA) and ATP levels decreased to the lowest on December 30. The correlation analysis showed that GR had the significant positive relevance to sperm motility and VSL/VCL, while ·OH had negative relevance to them.

Metabolomic fingerprinting of pig seminal plasma identifies in vivo fertility biomarkers

Background:Metabolomic approaches,which include the study of low molecular weight molecules,are an emerging-omics technology useful for identification of biomarkers.In this field,nuclear magnetic resonance(NMR)spectroscopy has already been used to uncover(in)fertility biomarkers in the seminal plasma(SP)of several mammalian species.However,NMR studies profiling the porcine SP metabolome to uncover in vivo fertility biomarkers are yet to be carried out.Thus,this study aimed to evaluate the putative relationship between SPmetabolites and in vivo fertility outcomes.To this end,24 entire ejaculates(three ejaculates per boar)were collected from artificial insemination(AI)-boars throughout a year(one ejaculate every 4 months).Immediately after collection,ejaculates were centrifuged to obtain SP-samples,which were stored for subsequent metabolomic analysis by NMR spectroscopy.Fertility outcomes from 1525 inseminations were recorded over a year,including farrowing rate,litter size,stillbirths per litter and the duration of pregnancy.Results:A total of 24 metabolites were identified and quantified in all SP-samples.Receiver operating characteristic(ROC)curve analysis showed that lactate levels in SP had discriminative capacity for farrowing rate(area under the curve[AUC]=0.764)while carnitine(AUC=0.847),hypotaurine(AUC=0.819),sn-glycero-3-phosphocholine(AUC=0.833),glutamate(AUC=0.799)and glucose(AUC=0.750)showed it for litter size.Similarly,citrate(AUC=0.743),creatine(AUC=0.812),phenylalanine(AUC=0.750),tyrosine(AUC=0.753)and malonate(AUC=0.868)levels had discriminative capacity for stillbirths per litter;and malonate(AUC=0.767)and fumarate(AUC=0.868)levels for gestation length.Conclusions:The assessment of selected SP-metabolites in ejaculates through NMR spectroscopy could be considered as a promising non-invasive tool to predict in vivo fertility outcomes in pigs.Moreover,supplementing AI-doses with specific metabolites should also be envisaged as a way to improve their fertility potential.

Characterization of proteins in cryopreserved and non-cryopreserved seminal plasma of dairy bulls of dif-fering fertility

Seminal plasma is composed of secretions from accessory sex glands, which are mixed with sperm at ejaculation and contribute the majority of semen volume. Seminal plasma is considered a transport and support medium for sperm in the female reproductive tract. Because seminal plasma is not required for fertilization, the importance of its constituents to the establishment of normal pregnancy has been overlooked. Four seminal plasma proteins, Osteopontin, Sper-madhesin Z13, BSP 30 kDa and Phospholipase A2, have been identified as markers of fertility in dairy bulls (Cancel et al., 1997;Moura et al., 2006, 2007). The objective of the present study was to characterize the expression patterns of these proteins and other proteins found to be of interest in seminal plasma of cryopreserved and non-cryopreserved bull semen. Seminal plasma samples were obtained from 16 mature Hol-stein-Friesian bulls at Select Sires Inc. Samples were divided into two groups based on assigned fertility score expressed as the percentage point deviation (PD) of the bull’s non-return rate (NRR) from the average NRR of all bulls in the Select Sires Inc. reproductive management program. Group 1 (high fertility bulls, n = 8) 1.9 ≤ PD ≤ 2.7%, and group 2 (low fertility bulls, n = 8) -6.5 ≤ PD ≤ 1.8 %. Additionally, the samples were categorized as processed (cryopreserved) or unprocessed (non-cryopreserved) for protein analysis. Protein expression was analyzed by 2-D fluorescence difference gel electrophoresis (2D-DIGETM). Protein spots were picked from a reference gel, analyzed by mass spectrometry and, subsequently identified by MS/MS ion searches performed on the SwissProt database. Protein expression did not differ (P > 0.05) with fertility grouping but displayed two distinct patterns among the processing groups: majority of the functional proteins were highly expressed in seminal plasma of non-cryopreserved semen while the cryopreserved semen contained mainly structural/extender derived proteins. Functional proteins identified included Spermadhesin Z13, BSP A1/2, BSP 30 kDa, Nucleobindin-1 and metalloproteinase inhibitor 2. Some of these proteins have been identified as anti-fertility or fertility enhancing agents in males. Whether this alteration in protein expression after processing might affect semen fertility is worthy of further evaluation.

Heparin-binding proteins from boar seminal plasma affecting the release of prostaglandins and interleukin-6 by porcine endometrial and cervical cells and bovine endometrial cells

The objectives of this study were to explore whether heparin-binding proteins, separated by fast protein liquid chromatography from boar seminal plasma influence the release of prostaglandins F2α, (PGF2α), E2 (PGE2) and interleukin-6 (IL-6) by porcine endometrial and cervical cells and even bovine endometrial cells. In Experiment I, we showed that release of PGF2α by endometrial epithelial, endometrial stromal and cervical stromal cells to the medium was inhibited (p α (TNFα) stimulated release of IL-6 by endometrial and cervical stromal cells after 24 h incubation, but in the presence of heparin-binding proteins, this stimulation was attenuated. Release of PGF2α by cryopreserved (Experiment II) and primary (Experiment III) cervical stromal cells was significantly inhibited after 3 h incubation with 66 - 95.4 μg of heparin- binding proteins. A significant inhibition of PGE2 release by cryopreserved and primary cervical stromal cells was already achieved after incubation with 16.5 - 23.9 μg of heparin-binding proteins. The release of IL-6 by cryopreserved cells was stimulated after 3 h incubation with heparin- binding proteins in a dose dependent manner in contrast to the release of IL-6 by freshly isolated cervical stromal cells. We also found (Experiment IV) that porcine heparin-binding seminal plasma proteins inhibited release of PGF2α and stimulated release of IL-6 by bovine endometrial epithelial cells. In conclusion, a group of heparin-binding proteins separated by fast protein liquid chromatography from boar seminal plasma inhibit PGF2α, PGE2 and stimulate IL-6 release by porcine endometrial and cervical cells and even by bovine endometrial cells. Thus, these proteins have a similar effect as the entire seminal plasma.

Effect of transient scrotal hyperthermia on sperm parameters, seminal plasma biochemical markers, and oxidative stress in men

In this experimental prospective study, we aimed to analyze the effect of transient scrotal hyperthermia on the male reproductive organs, from the perspective of sperm parameters, semen plasma biochemical markers, and oxidative stress, to evaluate whether different frequencies of heat exposure cause different degrees of damage to spermatogenesis. Two groups of volunteers （10 per group） received testicular warming in a 43~C water bath 10 times, for 30 min each time： group 1：10 consecutive days; group 2： once every 3 days. Sperm parameters, epididymis and accessory sex gland function, semen plasma oxidative stress and serum sex hormones were tested before treatment and in the 16-week recovery period after treatment. At last, we found an obvious reversible decrease in sperm concentration （P = 0.005 for Group 1 and P = 0.008 for Group 2 when the minimums were compared with baseline levels, the same below）, motility （P= 0.009 and 0.021, respectively）, the hypoosmotic swelling test score （P-- 0.007 and 0.008, respectively）, total acrosin activity （P = 0.018 and 0.009, respectively）, and an increase in the seminal plasma malondialdehyde concentration （P = 0.005 and 0.017, respectively）. The decrease of sperm concentration was greater for Group 2 than for Group 1 （P = 0.031）. We concluded that transient scrotal hyperthermia seriously, but reversibly, negatively affected the spermatogenesis, oxidative stress may be involved in this process. In addition, intermittent heat exposure more seriously suppresses the spermatogenesis compared to consecutive heat exposure. This may be indicative for clinical infertility etiology analysis and the design of contraceptive methods based on heat stress.

Proteomic profile of seminal plasma in adolescents and adults with treated and untreated varicocele

Varicocele, the most important treatable cause of male infertility, is present in 15% of adult males, 35% of men with primary infertility, and 80% of men with secondary infertility. On the other hand, 80% of these men will not present infertility. Therefore, there is a need to differentiate a varicocele that is exerting a deleterious effect that is treatable from a ＂silent＂ varicocele. Despite the growing evidence of the cellular effects of varicocele, its underlying molecular mechanisms are still eluding. Proteomics has become a promising area to determine the reproductive biology of semen as well as to improve diagnosis of male infertility. This review aims to discuss the state-of-art in seminal plasma proteomics in patients with varicocele to discuss the challenges in undertaking these studies, as well as the future outlook derived from the growing body of evidence on the seminal proteome.

Seminal plasma miR-192a： a biomarker predicting successful resolution of nonobstructive azoospermia following varicocele repair

This study was performed to investigate a potential marker for the presence of spermatozoa in the ejaculate following varicocelectomy in Chinese men with nonobstructive azoospermia and varicoceles. The micro-RNA （miR）-192a levels in seminal plasma and testicular tissue were evaluated by quantitative real-time polymerase chain reaction from 60 men with nonobstructive azoospermia and varicoceles （Group A： 27 men with spermatozoa found in the ejaculate after surgery; Group B： 33 men without spermatozoa found in the ejaculate after surgery） and 30 controls. The seminal plasma and testicular tissue miR-192a levels were higher in Group B than in Group A and the controls （P〈 0.001）, and there was no significant difference between Group A and the controls （P〉 0.05）. Apoptosis and proliferation assays with miR mimics and inhibitors showed that miR-192a induced GC-2 cell apoptosis through the activation of Caspase-3 protein. Thus, seminal plasma miR-192a appears to be a potential marker for successfully indicating spermatozoa in the ejaculate following microsurgical varicocelectomy in men with nonobstructive azoospermia and varicoceles. Seminal plasma miR-192a may be a useful clinical marker for prescreening to determine which patients with nonobstructive azoospermia and varicoceles would benefit from varicocelectomy.