Aim: To detect the expression of hepatitis B virus (HBV) genes (HB S and C genes) in early embryonic cells after introducing motile human sperm carrying HBV DNA into zona-free hamster oocytes via the in vitro fer...Aim: To detect the expression of hepatitis B virus (HBV) genes (HB S and C genes) in early embryonic cells after introducing motile human sperm carrying HBV DNA into zona-free hamster oocytes via the in vitro fertilization (IVF) technique. Methods: Human sperm-mediated HBV genes were delivered into zona-free hamster oocytes by the IVF method. Polymerase chain reaction (PCR) was used to detect HB S and pre-Core/Core (pre-C/C) coding genes both in one- and two-cell embryos. Reverse transcription-PCR (RT-PCR) analysis was used to study the expression of the two genes. Fluorescence in situ hybridization (FISH) analysis using the full-length HBV DNA as the hybridization probe was performed to confirm the integration of viral DNA in the host embryonic genome. Results: Both HB S and pre-C/C coding genes are present and transcribed in one- and two-cell embryos originated from hamster ova IVF with human spermatozoa carrying HBV DNA sequences. Conclusion: Sperm-mediated HBV genes are able to replicate and express themselves in early embryonic cells. These results provide direct evidence that HBV DNA could transmit vertically to the next generation via the male germ line.展开更多
<abstract>Aim: To study the protein changes of spermatozoa associated with sperm motility during sperm cryopreservation and its mechanism. Methods: In 18 healthy men, the seminal sperm motility and HSP90 levels ...<abstract>Aim: To study the protein changes of spermatozoa associated with sperm motility during sperm cryopreservation and its mechanism. Methods: In 18 healthy men, the seminal sperm motility and HSP90 levels were studied before and after cryopreservation using SDS-PAGE, Western blotting and computerized image analysis. Results: The sperm motility declined significantly after cryopreservation (P<0.01). The average grey level and the integrated grey level of sperm HSP90 before cooling were 34.1±3.2 and 243.0±21.6, respectively, while those after thawing were 23.2±2.5 and 105.7±28.5, respectively. Both parameters were decreased significantly (P<0.01). No HSP90 was found in the seminal plasma before and after cryopreservation. Conclusion: HSP90 in human spermatozoa was decreased substantially after cryopreservation. This may result from protein degradation, rather than leakage into the seminal plasma.展开更多
<abstract>Aim: To investigate the human sperm oxygen/energy consumption and zinc content in relation to motility. Methods: In washed spermatozoa from 67 ejaculates, the oxygen consumption was determined. Followi...<abstract>Aim: To investigate the human sperm oxygen/energy consumption and zinc content in relation to motility. Methods: In washed spermatozoa from 67 ejaculates, the oxygen consumption was determined. Following calculation of the total oxygen consumed by the Ideal Gas Law, the energy consumption of spermatozoa was calculated. In addition, the zinc content of the sperm was determined using an atomic absorption spectrometer. The resulting data were correlated to the vitality and motility. Results: The oxygen consumption averaged 0.24μmol/106 sperm×24 h, 0.28μmol/106 live sperm×24 h and 0.85μmol/106 live & motile sperm×24 h. Further calculations revealed that sperm motility was the most energy consuming process (164.31 mJ/106 motile spermatozoa×24 h), while the oxygen consumption of the total spermatozoa was 46.06 mJ/106 spermatozoa×24 h. The correlation of the oxygen/ energy consumption and zinc content with motility showed significant negative correlations (r= -0.759; P<0.0001 and r=-0.441; P<0.0001, respectively). However, when correlating sperm energy consumption with the zinc content, a significant positive relation (r=0.323; P=0.01) was observed. Conclusion: Poorly motile sperm are actually wasting the available energy. Moreover, our data clearly support the 'Geometric Clutch Model' of the axoneme function and demonstrate the importance of the outer dense fibers for the generation of sperm motility, especially progressive motility.展开更多
Aim: To determine the cellular distribution of secretory phospholipase A2 (sPLA2) in dependence on the acrosomal state and under the action of elastase released under inflammatory processes from leukocytes. Methods...Aim: To determine the cellular distribution of secretory phospholipase A2 (sPLA2) in dependence on the acrosomal state and under the action of elastase released under inflammatory processes from leukocytes. Methods: Acrosome reaction of spermatozoa was triggered by calcimycin. Human leukocyte elastase was used to simulate inflammatory conditions. To visualize the distribution of sPLA2 and to determine the acrosomal state, immunofluorescence techniques and lectin binding combined with confocal laser scanning fluorescence microscopy and flow cytometry were used. Results: Although sPLA2 was detected at the acrosome and tail regions in intact spermatozoa, it disappeared from the head region after triggering the acrosome reaction. This release of sPLA2 was associated with enhanced binding of annexin V-fluoroscein isothiocyanate (FITC) to spermatozoa surfaces, intercalation of ethidium-homodimer I, and binding of FITC-labelled concanavalin A at the acrosomal region. Spermatozoa from healthy subjects treated with elastase were characterized by release of sPLA2, disturbance of acrosome structure, and loss of vitality. Conclusion: The ability of spermatozoa to release secretory phospholipase A2 is related to the acrosomal state. Premature destabi- lization of the acrosome and loss of sPLA2 can occur during silent inflammations in the male genital tract. The distribution pattern of sPLA2 in intact spermatozoa might be an additional parameter for evaluating sperm quality.展开更多
A variety of natural and artificial cryoprotectant extenders have been explored to enhance sperm recovery following cryopreservation-thawing process. The current investigation is aimed at evaluating the effect of acet...A variety of natural and artificial cryoprotectant extenders have been explored to enhance sperm recovery following cryopreservation-thawing process. The current investigation is aimed at evaluating the effect of acetyl-L-carnitine on human spermatozoa and reactive species oxygen(ROS) level after freezing-thawing process. The spermatozoa were collected from 35 male patients diagnosed as having asthenospermia. The cryopreservation of human spermatozoa treated with acetyl-L-carnitine at different concentrations(group B: 2.5 mmol/L, group C: 7.5 mmol/L, group D: 15 mmol/L) was compared with control(group A: no acetyl-L-carnitine given). For the frozen-thawed spermatozoa, the viability, motility and DNA integrity were measured by comet assay, acrosome integrity by FITC-PNA staining and ROS level was determined in each group. The results showed that there were no significant differences in motility and viability between group A and group B, while the motility and viability of spermatozoa in group C and group D were significantly increased as compared with those in group A. As compared with group A, the values for DNA integrity parameters including comet rate(CR), tail DNA percentage(TD), tail length(TL) and Oliver tail moment(OTM) were significantly reduced in group C and group D. Group C and group D also displayed a higher proportion of intact acrosome than group A. No significant difference in ROS level was found between group A and group B, while with the increase in acetyl-L-carnitine concentration, the ROS level in groups C and D was significantly reduced as compared with that in group A. In conclusion, acetyl-L-carnitine at a concentration of 7.5 mmol/L is an effective antioxidant against cryo-damage on post-thawed human spermatozoa.展开更多
Aim: To investigate whether adriamycin induces DNA damage and the formation of γH2AX (the phosphorylated form of histone H2AX) foci in mature spermatozoa. Methods: Human spermatozoa were treated with adriamycin a...Aim: To investigate whether adriamycin induces DNA damage and the formation of γH2AX (the phosphorylated form of histone H2AX) foci in mature spermatozoa. Methods: Human spermatozoa were treated with adriamycin at different concentrations, γH2AX was analyzed by immunofluorescent staining and flow cytometry and doublestrand breaks (DSB) were detected by the comet assay. Results: The neutral comet assay revealed that the treatment with adriamycin at 2 μg/mL for different times (0.5, 2, 8 and 24 h), or for 8 h at different concentrations (0,4, 2 and 10 μg/mL), induced significant DSB in spermatozoa. Immunofluorent staining and flow cytometry showed that the expression of γH2AX was increased in a dose-dependent and time-dependant manner after the treatment of adriamycin. Adriamycin also induced the concurrent appearance of DNA maintenance/repair proteins RAD50 and 53BP 1 with γH2AX in spermatozoa. Wortmannin, an inhibitor of the phosphatidylinositol 3-kinase (PI3K) family, abolished the co-appearance of these two proteins with γH2AX. Conclusion: Human mature spermatozoa have the same response to DSB-induced H2AX phosphorylation and subsequent recruitment of DNA maintenance/ repair proteins as somatic cells.展开更多
Objective: To study the vitronectin expression in human spermato-zoa and its role in fertilization. Methods: Spermatozoa from 14 fer-tile and 8 infertile men with normal semen data were studied. Follow-ing recovery of...Objective: To study the vitronectin expression in human spermato-zoa and its role in fertilization. Methods: Spermatozoa from 14 fer-tile and 8 infertile men with normal semen data were studied. Follow-ing recovery of motile populations by swim-up, spermatozoa were ca-pacitated and immunostained with rabbit anti-human Vn polyclonal an-tibody and goat anti-rabbit IgG-FTTC second antibody. The percentageof spermatozoa expressing Vn was determined using a FAScan flowcytometer. Meanwhile, the fertilizing ability of capacitated spermato-zoa was determined with human spermatozoa zona-free hamster eggpenetration assay (SPA). Results: The mean ± s proportion ofspermatozoa expressing Vn of fertile men was 21.24% ± 11.70% and3.64±3.27% for infertile men (P<0.05). The penetration rate ofSPA in the fertile group was > 10%, but that in the infertile group ,< 10%. There is a correlation between positive sperm Vn expressionand percentage of eggs penetrated (r=0.476). Conclusion: Theseresults indicate the expression of Vn in human capacitated spermatozoaand its correlation with the fertilizing ability. The abnormal expressionof Vn on human spermatozoa may be one of the unexplained infertilereasons. (Reprod Contracep 2001; 21: 24-28)展开更多
Aim:To detect the expression of hepatitis B virus(HBV)genes(HB S and C genes)in early embryonic cells after introducing motile human sperm carrying HBV DNA into zona-free hamster oocytes via the in vitro fertilization...Aim:To detect the expression of hepatitis B virus(HBV)genes(HB S and C genes)in early embryonic cells after introducing motile human sperm carrying HBV DNA into zona-free hamster oocytes via the in vitro fertilization(IVF) technique.Methods:Human sperm-mediated HBV genes were delivered into zona-free hamster oocytes by the IVF method.Polymerase chain reaction(PCR)was used to detect HB S and pre-Core/Core(pre-C/C)coding genes both in one-and two-cell embryos.Reverse transcription-PCR(RT-PCR)analysis was used to study the expression of the two genes.Fluorescence in situ hybridization(FISH)analysis using the full-length HBV DNA as the hybridization probe was performed to confirm the integration of viral DNA in the host embryonic genome.Results:Both HB S and pre-C/C coding genes are present and transcribed in one-and two-cell embryos originated from hamster ova IVF with human spermatozoa carrying HBV DNA sequences.Conclusion:Sperm-mediated HBV genes are able to replicate and express themselves in early embryonic cells.These results provide direct evidence that HBV DNA could transmit vertically to the next generation via the male germ line.展开更多
The comet assay was performed on mouse and human spermatozoa to examine the effect of alkaline DNA unwinding time. The spermatozoa were treated in vitrowith the DNA-damaging agents, methyl methanesulfonate (MMS) or ...The comet assay was performed on mouse and human spermatozoa to examine the effect of alkaline DNA unwinding time. The spermatozoa were treated in vitrowith the DNA-damaging agents, methyl methanesulfonate (MMS) or hydrogen peroxide (Hz02), and then embedded in agarose gel on glass sl ides. The slides were immersed in alkaline solution (〉pH 13) for 1, 5, 10 and 20 min, and then subjected to the electrophoresis under neutral conditions. In mouse spermatozoa, comet tails seen in solvent controls became brighter and longer as the alkaline DNA unwinding time increased. However, in the MMS-treated mouse spermatozoa, a smaller difference in the damage from that in the solvent control was seen with time within a dose. DNA damage induced by H2O2 could also be detected accurately after alkali treatment for 1-20 min. In human spermatozoa, DNA damage induced by MMS and H2O2 could be detected in a dose-dependent manner after alkali treatment for 1 min. The ability of the comet assay to detect DNA damage was not adversely affected by the short period (1 min) of the alkaline DNA unwinding time.展开更多
AMP-activated kinase (AMPK), a protein that regulates energy balance and metabolism, has recently been identified in boar spermatozoa where regulates key functional sperm processes essential for fertilization. This ...AMP-activated kinase (AMPK), a protein that regulates energy balance and metabolism, has recently been identified in boar spermatozoa where regulates key functional sperm processes essential for fertilization. This work's aims are AMPK identification, intracellular localization, and their role in human spermatozoa function. Semen was obtained from healthy human donors. Sperm AMPK and phospho-Thr172-AMPK were analyzed by Western blotting and indirect immunofluorescence. High- and low-quality sperm populations were separated by a 40%-80% density gradient. Human spermatozoa motility was evaluated by an Integrated Semen Analysis System (ISAS) in the presence or absence of the AMPK inhibitor compound C (CC). AMPK is localized along the human spermatozoa, at the entire acrosome, midpiece and tail with variable intensity, whereas its active form, phospho-Thr172-AMPK, shows a prominent staining at the acrosome and sperm tail with a weaker staining in the midpiece and the postacrosomal region. Interestingly, spermatozoa bearing an excess residual cytoplasm show strong AMPK staining in this subcellular compartment. Both AMPK and phospho-Thr172-AMPK human spermatozoa contents exhibit important individual variations. Moreover, active AMPK is predominant in the high motility sperm population, where shows a stronger intensity compared with the low motility sperm population. Inhibition of AMPK activity in human spermatozoa by CC treatment leads to a significant reduction in any sperm motility parameter analyzed: percent of motile sperm, sperm velocities, progressivity, and other motility coefficients. This work identifies and points out AMPK as a new molecular mechanism involved in human spermatozoa motility. Further AMPK implications in the clinical efficiency of assisted reproduction and in other reproductive areas need to be studied.展开更多
Reactive oxygen species(ROS)production is a by-product of mitochondrial activity and is necessary for the acquisition of the capacitated state,a requirement for functional spermatozoa.However,an increase in oxidative ...Reactive oxygen species(ROS)production is a by-product of mitochondrial activity and is necessary for the acquisition of the capacitated state,a requirement for functional spermatozoa.However,an increase in oxidative stress,due to an abnormal production of ROS,has been shown to be related to loss of sperm function,highlighting the importance of an accurate detection of sperm ROS,given the specific nature of this cell.In this work,we tested a variety of commercially available fluorescent probes to detect ROS and reactive nitrogen species(RNS)in human sperm,to define their specificity.Using both flow cytometry(FC)and fluorescence microscopy(FM),we confirmed that MitoSOX™Red and dihydroethidium(DHE)detect superoxide anion(as determined using antimycin A as a positive control),while DAF-2A detects reactive nitrogen species(namely,nitric oxide).For the first time,we also report that RedoxSensor™Red CC-1,CellROX®Orange Reagent,and MitoPYl seem to be mostly sensitive to hydrogen peroxide,but not superoxide.Furthermore,mean fluorescence intensity(and not percentage of labeled cells)is the main parameter that can be reproducibly monitored using this type of methodology.展开更多
Objective:Optimal reference genes are critical for accurate normalization and reliable interpretation of gene expression quantification data.Recently,several strategies have been utilized for validating reference gene...Objective:Optimal reference genes are critical for accurate normalization and reliable interpretation of gene expression quantification data.Recently,several strategies have been utilized for validating reference genes in different human tissues.However,no universal reference genes have been described that accurately summarize transcriptional activity in human spermatozoa.Methods:Using quantitative reverse transcription-polymerase chain reaction(RT-qPCR),we evaluated ten commonly used candidate reference genes between two groups of human cryopreserved donor sperm with different pregnancy rates.We assessed the stability of reference genes using three different algorithms,namely geNorm,NormFinder,and BestKeeper.We then identified the most stable reference genes.Results:Male-enhanced antigen 1(MEA1)was identified as the most stably expressed reference gene,followed by testis-enhanced gene transcript(TEGT).Conclusions:We comprehensively identified MEA1 and TEGT as the most stably expressed reference genes for the normalization of gene expression data in human spermatozoa.展开更多
Aim: To investigate the distribution of cation channel of sperm 1 (CATSPER1) protein and the presence of CATSPER1 mRNA in human testis and ejaculated spermatozoa. The influence of anti-human CATSPER1 antibody upon ...Aim: To investigate the distribution of cation channel of sperm 1 (CATSPER1) protein and the presence of CATSPER1 mRNA in human testis and ejaculated spermatozoa. The influence of anti-human CATSPER1 antibody upon human sperm motility was used to evaluate the function of human CATSPER1 and to estimate its possible use as a target for immunocontraception. Methods: Human ejaculated sperm from normozoospermic donors (n = 12) and liquid nitrogen frozen human testis were used for the study of mRNA and protein expression of CATSPER1 by reverse transcription polymerase chain reaction (RT-PCR) and immunohistochemistry, respectively. Spermatozoa from normozoospermic donors (n = 12) were individually processed using a swim-up procedure and were then incubated with CATSPER1 antibody at final concentrations of 20, 4 and 0.8 μg/mL. After 1, 2 and 6 h incubation, progressive motility and fast progressive motility were measured by means of computer-assisted semen analysis. Results: CATSPER1 transcript was detected in both human testis and each human ejaculated semen sample. CATSPER1 protein expressed in the membrane of spermatid and was localized in the principal piece of the sperm tail. The application of CATSPER1 antibody at all concentrations significantly inhibited both progressive motility and fast progressive motility after 1, 2 and 6 h incubation, and significant dose-dependent changes were observed. Conclusion: CATSPER1 is meiotically and post-meiotically expressed in human testis tissue. CATSPER1 mRNA in human ejaculated spermatozoa could be a more feasible target for study and infertility screening than testis biopsy. In addition, our results suggest that human CATSPER1 could be a possible target for immunocontraception.展开更多
Aim:To investigate the distribution of cation channel of sperm 1(CATSPER1)protein and the presence of CATSPER1 mRNA in human testis and ejaculated spermatozoa.The influence of anti-human CATSPER1 antibody upon human s...Aim:To investigate the distribution of cation channel of sperm 1(CATSPER1)protein and the presence of CATSPER1 mRNA in human testis and ejaculated spermatozoa.The influence of anti-human CATSPER1 antibody upon human sperm motility was used to evaluate the function of human CATSPER1 and to estimate its possible use as a target for immunocontraception.Methods:Human ejaculated sperm from normozoospermic donors(n=12)and liquid nitro- gen frozen human testis were used for the study of mRNA and protein expression of CATSPER1 by reverse transcliption polymerase chain reaction(RT-PCR)and immunohistochemistry,respectively.Spermatozoa from nonnozoospermic donors(n=12)were individually processed using a swim-up procedure and were then incubated with CATSPER 1 antibody at final concentrations of 20,4 and 0.8μg/mL.After 1,2 and 6h incubation,progressive motility and fast progressive motility were measured by means of computer-assisted semen analysis.Results:CATSPER1 transcript was detected in both human testis and each human ejaculated semen sample.CATSPER1 protein expressed in the membrane of spermatid and was localized in the principal piece of the sperm tail.The application of CATSPER1 antibody at all concentrations significantly inhibited both progressive motility and fast progressive motility after 1,2 and 6h incubation,and significant dose-dependent changes were observed.Conclusion:CATSPER1 is meiotically and post-meiotically expressed in human testis tissue.CATSPER1 mRNA in human ejaculated spermatozoa could be a more feasible target for study and infertility screening than testis biopsy.In addition,our results suggest that human CATSPER1 could be a possible target for immunocontraception.(Asian J Androl 2006 May:8:301-306)展开更多
Human spermatozoa may chemotactically find out the egg by following an increasing gradient of attractant molecules. Although human spermatozoa have been observed to show several of the physiological characteristics of...Human spermatozoa may chemotactically find out the egg by following an increasing gradient of attractant molecules. Although human spermatozoa have been observed to show several of the physiological characteristics of chemotaxis, the chemotactic pattern of movement has not been easy to describe. However, it is apparent that chemotactic cells may be identified while returning to the attractant source. This study characterizes the pattern of movement of human spermatozoa during chemotactic re-orientation towards a progesterone source, which is a physiological attractant candidate. By means of videomicroscopy and image analysis, a chemotactic pattern of movement was identified as the spermatozoon returned towards the source of a chemotactic concentration of progesterone (10 pmol I^-1). First, as a continuation of its original path, the spermatozoon swims away from the progesterone source with linear movement and then turns back with a transitional movement that can be characterized by an increased velocity and decreased linearity. This sperm behaviour may help the spermatozoon to re-orient itself towards a progesterone source and may be used to identify the few cells that are undergoing chemotaxis at a given time.展开更多
The occurrence of tyrosine phosphorylation (TP) in the sperm head during capacitation has been poorly investigated, and no data exist on the relationship of its dynamics with the acquisition of sperm fertilizing abi...The occurrence of tyrosine phosphorylation (TP) in the sperm head during capacitation has been poorly investigated, and no data exist on the relationship of its dynamics with the acquisition of sperm fertilizing ability. This study localized TP of head proteins in human spermatozoa during capacitation and explored its relationship with acquisition of the ability to display progesterone (P)-stimulated acrosome reactions (ARs) and to penetrate zona-free hamster oocytes. By immunofluorescence, TP immunoreactivity was revealed in the acrosomal region of formaldehyde-fixed/unpermeabilized samples, whereas it was abolished in fixed/permeabilized samples, in which TP immunoreactivity was high in the principal piece. No TP immunoreaetivity was detectable in unfixed spermatozoa. Head TP immunoreactivity was localized externally to the acrosome, close to the cytoplasmic membrane, as assessed by transmission electron microscopy. The increase in head TP was an early event during capacitation, occurring within 1 h in capacitating conditions. At this time, the P-stimulated ARs were also increased, whereas egg penetration was as poor as in uncapacitated spermatozoa. At 5 h of capacitation, the extent of neither head TP nor the P-induced ARs were greater than that at 1 h, whereas egg penetration had significantly increased. Seminal plasma inhibited head TP, P-induced ARs and egg penetration. None of these inhibitory effects, unlike those on tail TP, were prevented by the cAMP analogue dbcAMP (N,2-O-dibutyryladenosine 3',5'-cyclic monophosphate). In conclusion, head TP is a subsurface event occurring early during capacitation and is closely related to acquisition of the ability to display P-stimulated ARs, whereas the ability to fuse with oolemma and to decondense is a later capacitation-related event.展开更多
Aim: To study the integration of hepatitis B virus (HBV) DNA into sperm chromosomes in hepatitis B patients and the features of its integration. Methods: Sperm chromosomes of 14 subjects (5 healthy controls and 9 HB p...Aim: To study the integration of hepatitis B virus (HBV) DNA into sperm chromosomes in hepatitis B patients and the features of its integration. Methods: Sperm chromosomes of 14 subjects (5 healthy controls and 9 HB patients, including 1 acute hepatitis B, 2 chronic active hepatitis B, 4 chronic persistent hepatitis B, 2 HBsAg chronic carriers with no clinical symptoms) were prepared using interspecific in vitro fertilization between zona-free hamster oocytes and human spermatozoa. Fluorescence in situ hybridization (FISH) to sperm chromosome spreads was carried out with biotin-labeled full length HBV DNA probe to detect the specific HBV DNA sequences in the sperm chromosomes. Results: Specific fluorescent signal spots for HBV DNA were seen in sperm chromosomes of one patient with chronic persistent hepatitis B. In 9(9/42) sperm chromosome complements containing fluorescent signal spots, one presented 5 obvious FISH spots and the others 2 to 4 signals. The fluorescence intensity showed significant difference among the signal spots. The distribution of signal sites among chromosomes seems to be random. Conclusion: HBV could integrate into human sperm chromosomes. Results suggest that the possibility of vertical transmission of HBV via the germ line to the next generation is present.展开更多
基金Acknowledgment This work was supported by a grant from the National Nature Science Foundation of China (No. 39970374). The authors wish to thank Professor Yi-Pong Hu, Second Military Medical University of China, for his kindness in providing us the recombinant plasmid (pBR322-HBV). We wish to thank Mr. Michael Talion of Shantou University Medical College, English Language Training Section for his assistance in proofreading this manuscript. We gratefully acknowledge the support of the leaders of Shantou University Medical College.
文摘Aim: To detect the expression of hepatitis B virus (HBV) genes (HB S and C genes) in early embryonic cells after introducing motile human sperm carrying HBV DNA into zona-free hamster oocytes via the in vitro fertilization (IVF) technique. Methods: Human sperm-mediated HBV genes were delivered into zona-free hamster oocytes by the IVF method. Polymerase chain reaction (PCR) was used to detect HB S and pre-Core/Core (pre-C/C) coding genes both in one- and two-cell embryos. Reverse transcription-PCR (RT-PCR) analysis was used to study the expression of the two genes. Fluorescence in situ hybridization (FISH) analysis using the full-length HBV DNA as the hybridization probe was performed to confirm the integration of viral DNA in the host embryonic genome. Results: Both HB S and pre-C/C coding genes are present and transcribed in one- and two-cell embryos originated from hamster ova IVF with human spermatozoa carrying HBV DNA sequences. Conclusion: Sperm-mediated HBV genes are able to replicate and express themselves in early embryonic cells. These results provide direct evidence that HBV DNA could transmit vertically to the next generation via the male germ line.
文摘<abstract>Aim: To study the protein changes of spermatozoa associated with sperm motility during sperm cryopreservation and its mechanism. Methods: In 18 healthy men, the seminal sperm motility and HSP90 levels were studied before and after cryopreservation using SDS-PAGE, Western blotting and computerized image analysis. Results: The sperm motility declined significantly after cryopreservation (P<0.01). The average grey level and the integrated grey level of sperm HSP90 before cooling were 34.1±3.2 and 243.0±21.6, respectively, while those after thawing were 23.2±2.5 and 105.7±28.5, respectively. Both parameters were decreased significantly (P<0.01). No HSP90 was found in the seminal plasma before and after cryopreservation. Conclusion: HSP90 in human spermatozoa was decreased substantially after cryopreservation. This may result from protein degradation, rather than leakage into the seminal plasma.
文摘<abstract>Aim: To investigate the human sperm oxygen/energy consumption and zinc content in relation to motility. Methods: In washed spermatozoa from 67 ejaculates, the oxygen consumption was determined. Following calculation of the total oxygen consumed by the Ideal Gas Law, the energy consumption of spermatozoa was calculated. In addition, the zinc content of the sperm was determined using an atomic absorption spectrometer. The resulting data were correlated to the vitality and motility. Results: The oxygen consumption averaged 0.24μmol/106 sperm×24 h, 0.28μmol/106 live sperm×24 h and 0.85μmol/106 live & motile sperm×24 h. Further calculations revealed that sperm motility was the most energy consuming process (164.31 mJ/106 motile spermatozoa×24 h), while the oxygen consumption of the total spermatozoa was 46.06 mJ/106 spermatozoa×24 h. The correlation of the oxygen/ energy consumption and zinc content with motility showed significant negative correlations (r= -0.759; P<0.0001 and r=-0.441; P<0.0001, respectively). However, when correlating sperm energy consumption with the zinc content, a significant positive relation (r=0.323; P=0.01) was observed. Conclusion: Poorly motile sperm are actually wasting the available energy. Moreover, our data clearly support the 'Geometric Clutch Model' of the axoneme function and demonstrate the importance of the outer dense fibers for the generation of sperm motility, especially progressive motility.
文摘Aim: To determine the cellular distribution of secretory phospholipase A2 (sPLA2) in dependence on the acrosomal state and under the action of elastase released under inflammatory processes from leukocytes. Methods: Acrosome reaction of spermatozoa was triggered by calcimycin. Human leukocyte elastase was used to simulate inflammatory conditions. To visualize the distribution of sPLA2 and to determine the acrosomal state, immunofluorescence techniques and lectin binding combined with confocal laser scanning fluorescence microscopy and flow cytometry were used. Results: Although sPLA2 was detected at the acrosome and tail regions in intact spermatozoa, it disappeared from the head region after triggering the acrosome reaction. This release of sPLA2 was associated with enhanced binding of annexin V-fluoroscein isothiocyanate (FITC) to spermatozoa surfaces, intercalation of ethidium-homodimer I, and binding of FITC-labelled concanavalin A at the acrosomal region. Spermatozoa from healthy subjects treated with elastase were characterized by release of sPLA2, disturbance of acrosome structure, and loss of vitality. Conclusion: The ability of spermatozoa to release secretory phospholipase A2 is related to the acrosomal state. Premature destabi- lization of the acrosome and loss of sPLA2 can occur during silent inflammations in the male genital tract. The distribution pattern of sPLA2 in intact spermatozoa might be an additional parameter for evaluating sperm quality.
基金supported by grants from the Natural Science Foundation of Hubei Province(No.2016CFB352)Hubei Province Health and Family Planning Scientific Research Project(No.WJ2017M011)China Scholarship Council(No.201706275124)
文摘A variety of natural and artificial cryoprotectant extenders have been explored to enhance sperm recovery following cryopreservation-thawing process. The current investigation is aimed at evaluating the effect of acetyl-L-carnitine on human spermatozoa and reactive species oxygen(ROS) level after freezing-thawing process. The spermatozoa were collected from 35 male patients diagnosed as having asthenospermia. The cryopreservation of human spermatozoa treated with acetyl-L-carnitine at different concentrations(group B: 2.5 mmol/L, group C: 7.5 mmol/L, group D: 15 mmol/L) was compared with control(group A: no acetyl-L-carnitine given). For the frozen-thawed spermatozoa, the viability, motility and DNA integrity were measured by comet assay, acrosome integrity by FITC-PNA staining and ROS level was determined in each group. The results showed that there were no significant differences in motility and viability between group A and group B, while the motility and viability of spermatozoa in group C and group D were significantly increased as compared with those in group A. As compared with group A, the values for DNA integrity parameters including comet rate(CR), tail DNA percentage(TD), tail length(TL) and Oliver tail moment(OTM) were significantly reduced in group C and group D. Group C and group D also displayed a higher proportion of intact acrosome than group A. No significant difference in ROS level was found between group A and group B, while with the increase in acetyl-L-carnitine concentration, the ROS level in groups C and D was significantly reduced as compared with that in group A. In conclusion, acetyl-L-carnitine at a concentration of 7.5 mmol/L is an effective antioxidant against cryo-damage on post-thawed human spermatozoa.
文摘Aim: To investigate whether adriamycin induces DNA damage and the formation of γH2AX (the phosphorylated form of histone H2AX) foci in mature spermatozoa. Methods: Human spermatozoa were treated with adriamycin at different concentrations, γH2AX was analyzed by immunofluorescent staining and flow cytometry and doublestrand breaks (DSB) were detected by the comet assay. Results: The neutral comet assay revealed that the treatment with adriamycin at 2 μg/mL for different times (0.5, 2, 8 and 24 h), or for 8 h at different concentrations (0,4, 2 and 10 μg/mL), induced significant DSB in spermatozoa. Immunofluorent staining and flow cytometry showed that the expression of γH2AX was increased in a dose-dependent and time-dependant manner after the treatment of adriamycin. Adriamycin also induced the concurrent appearance of DNA maintenance/repair proteins RAD50 and 53BP 1 with γH2AX in spermatozoa. Wortmannin, an inhibitor of the phosphatidylinositol 3-kinase (PI3K) family, abolished the co-appearance of these two proteins with γH2AX. Conclusion: Human mature spermatozoa have the same response to DSB-induced H2AX phosphorylation and subsequent recruitment of DNA maintenance/ repair proteins as somatic cells.
文摘Objective: To study the vitronectin expression in human spermato-zoa and its role in fertilization. Methods: Spermatozoa from 14 fer-tile and 8 infertile men with normal semen data were studied. Follow-ing recovery of motile populations by swim-up, spermatozoa were ca-pacitated and immunostained with rabbit anti-human Vn polyclonal an-tibody and goat anti-rabbit IgG-FTTC second antibody. The percentageof spermatozoa expressing Vn was determined using a FAScan flowcytometer. Meanwhile, the fertilizing ability of capacitated spermato-zoa was determined with human spermatozoa zona-free hamster eggpenetration assay (SPA). Results: The mean ± s proportion ofspermatozoa expressing Vn of fertile men was 21.24% ± 11.70% and3.64±3.27% for infertile men (P<0.05). The penetration rate ofSPA in the fertile group was > 10%, but that in the infertile group ,< 10%. There is a correlation between positive sperm Vn expressionand percentage of eggs penetrated (r=0.476). Conclusion: Theseresults indicate the expression of Vn in human capacitated spermatozoaand its correlation with the fertilizing ability. The abnormal expressionof Vn on human spermatozoa may be one of the unexplained infertilereasons. (Reprod Contracep 2001; 21: 24-28)
文摘Aim:To detect the expression of hepatitis B virus(HBV)genes(HB S and C genes)in early embryonic cells after introducing motile human sperm carrying HBV DNA into zona-free hamster oocytes via the in vitro fertilization(IVF) technique.Methods:Human sperm-mediated HBV genes were delivered into zona-free hamster oocytes by the IVF method.Polymerase chain reaction(PCR)was used to detect HB S and pre-Core/Core(pre-C/C)coding genes both in one-and two-cell embryos.Reverse transcription-PCR(RT-PCR)analysis was used to study the expression of the two genes.Fluorescence in situ hybridization(FISH)analysis using the full-length HBV DNA as the hybridization probe was performed to confirm the integration of viral DNA in the host embryonic genome.Results:Both HB S and pre-C/C coding genes are present and transcribed in one-and two-cell embryos originated from hamster ova IVF with human spermatozoa carrying HBV DNA sequences.Conclusion:Sperm-mediated HBV genes are able to replicate and express themselves in early embryonic cells.These results provide direct evidence that HBV DNA could transmit vertically to the next generation via the male germ line.
文摘The comet assay was performed on mouse and human spermatozoa to examine the effect of alkaline DNA unwinding time. The spermatozoa were treated in vitrowith the DNA-damaging agents, methyl methanesulfonate (MMS) or hydrogen peroxide (Hz02), and then embedded in agarose gel on glass sl ides. The slides were immersed in alkaline solution (〉pH 13) for 1, 5, 10 and 20 min, and then subjected to the electrophoresis under neutral conditions. In mouse spermatozoa, comet tails seen in solvent controls became brighter and longer as the alkaline DNA unwinding time increased. However, in the MMS-treated mouse spermatozoa, a smaller difference in the damage from that in the solvent control was seen with time within a dose. DNA damage induced by H2O2 could also be detected accurately after alkali treatment for 1-20 min. In human spermatozoa, DNA damage induced by MMS and H2O2 could be detected in a dose-dependent manner after alkali treatment for 1 min. The ability of the comet assay to detect DNA damage was not adversely affected by the short period (1 min) of the alkaline DNA unwinding time.
文摘AMP-activated kinase (AMPK), a protein that regulates energy balance and metabolism, has recently been identified in boar spermatozoa where regulates key functional sperm processes essential for fertilization. This work's aims are AMPK identification, intracellular localization, and their role in human spermatozoa function. Semen was obtained from healthy human donors. Sperm AMPK and phospho-Thr172-AMPK were analyzed by Western blotting and indirect immunofluorescence. High- and low-quality sperm populations were separated by a 40%-80% density gradient. Human spermatozoa motility was evaluated by an Integrated Semen Analysis System (ISAS) in the presence or absence of the AMPK inhibitor compound C (CC). AMPK is localized along the human spermatozoa, at the entire acrosome, midpiece and tail with variable intensity, whereas its active form, phospho-Thr172-AMPK, shows a prominent staining at the acrosome and sperm tail with a weaker staining in the midpiece and the postacrosomal region. Interestingly, spermatozoa bearing an excess residual cytoplasm show strong AMPK staining in this subcellular compartment. Both AMPK and phospho-Thr172-AMPK human spermatozoa contents exhibit important individual variations. Moreover, active AMPK is predominant in the high motility sperm population, where shows a stronger intensity compared with the low motility sperm population. Inhibition of AMPK activity in human spermatozoa by CC treatment leads to a significant reduction in any sperm motility parameter analyzed: percent of motile sperm, sperm velocities, progressivity, and other motility coefficients. This work identifies and points out AMPK as a new molecular mechanism involved in human spermatozoa motility. Further AMPK implications in the clinical efficiency of assisted reproduction and in other reproductive areas need to be studied.
基金the Portuguese funding agency for science and technology(PD/BD/128237/2016-PhD Programme in Experimental Biology and Biomedicine)CNC is funded by FEDER,through Programa Operacional Factores de Competitividade-COMPETE 2020 and National funds via FCT under the project POCI-01-0145-FEDER-007440+1 种基金the European Regional Development Fund(ERDF),through the Centro 2020 Regional Operational Programme:project CENTRO-01-0145-FEDER-000012-HealthyAging2020,the COMPETE 2020-Operational Programme for Competitiveness and Internationalisationthe Portuguese national funds via FCT-Foundation for Science and Technology LP:project POCI-01-0145-FEDER 007440 and UID/NEU/04539/2019.
文摘Reactive oxygen species(ROS)production is a by-product of mitochondrial activity and is necessary for the acquisition of the capacitated state,a requirement for functional spermatozoa.However,an increase in oxidative stress,due to an abnormal production of ROS,has been shown to be related to loss of sperm function,highlighting the importance of an accurate detection of sperm ROS,given the specific nature of this cell.In this work,we tested a variety of commercially available fluorescent probes to detect ROS and reactive nitrogen species(RNS)in human sperm,to define their specificity.Using both flow cytometry(FC)and fluorescence microscopy(FM),we confirmed that MitoSOX™Red and dihydroethidium(DHE)detect superoxide anion(as determined using antimycin A as a positive control),while DAF-2A detects reactive nitrogen species(namely,nitric oxide).For the first time,we also report that RedoxSensor™Red CC-1,CellROX®Orange Reagent,and MitoPYl seem to be mostly sensitive to hydrogen peroxide,but not superoxide.Furthermore,mean fluorescence intensity(and not percentage of labeled cells)is the main parameter that can be reproducibly monitored using this type of methodology.
基金This work was supported by grants from the National Key Research and Development Program of China(2018YFC1003500)Medical Scientific Research Foundation of Guangdong Province of China(A2017531)。
文摘Objective:Optimal reference genes are critical for accurate normalization and reliable interpretation of gene expression quantification data.Recently,several strategies have been utilized for validating reference genes in different human tissues.However,no universal reference genes have been described that accurately summarize transcriptional activity in human spermatozoa.Methods:Using quantitative reverse transcription-polymerase chain reaction(RT-qPCR),we evaluated ten commonly used candidate reference genes between two groups of human cryopreserved donor sperm with different pregnancy rates.We assessed the stability of reference genes using three different algorithms,namely geNorm,NormFinder,and BestKeeper.We then identified the most stable reference genes.Results:Male-enhanced antigen 1(MEA1)was identified as the most stably expressed reference gene,followed by testis-enhanced gene transcript(TEGT).Conclusions:We comprehensively identified MEA1 and TEGT as the most stably expressed reference genes for the normalization of gene expression data in human spermatozoa.
文摘Aim: To investigate the distribution of cation channel of sperm 1 (CATSPER1) protein and the presence of CATSPER1 mRNA in human testis and ejaculated spermatozoa. The influence of anti-human CATSPER1 antibody upon human sperm motility was used to evaluate the function of human CATSPER1 and to estimate its possible use as a target for immunocontraception. Methods: Human ejaculated sperm from normozoospermic donors (n = 12) and liquid nitrogen frozen human testis were used for the study of mRNA and protein expression of CATSPER1 by reverse transcription polymerase chain reaction (RT-PCR) and immunohistochemistry, respectively. Spermatozoa from normozoospermic donors (n = 12) were individually processed using a swim-up procedure and were then incubated with CATSPER1 antibody at final concentrations of 20, 4 and 0.8 μg/mL. After 1, 2 and 6 h incubation, progressive motility and fast progressive motility were measured by means of computer-assisted semen analysis. Results: CATSPER1 transcript was detected in both human testis and each human ejaculated semen sample. CATSPER1 protein expressed in the membrane of spermatid and was localized in the principal piece of the sperm tail. The application of CATSPER1 antibody at all concentrations significantly inhibited both progressive motility and fast progressive motility after 1, 2 and 6 h incubation, and significant dose-dependent changes were observed. Conclusion: CATSPER1 is meiotically and post-meiotically expressed in human testis tissue. CATSPER1 mRNA in human ejaculated spermatozoa could be a more feasible target for study and infertility screening than testis biopsy. In addition, our results suggest that human CATSPER1 could be a possible target for immunocontraception.
文摘Aim:To investigate the distribution of cation channel of sperm 1(CATSPER1)protein and the presence of CATSPER1 mRNA in human testis and ejaculated spermatozoa.The influence of anti-human CATSPER1 antibody upon human sperm motility was used to evaluate the function of human CATSPER1 and to estimate its possible use as a target for immunocontraception.Methods:Human ejaculated sperm from normozoospermic donors(n=12)and liquid nitro- gen frozen human testis were used for the study of mRNA and protein expression of CATSPER1 by reverse transcliption polymerase chain reaction(RT-PCR)and immunohistochemistry,respectively.Spermatozoa from nonnozoospermic donors(n=12)were individually processed using a swim-up procedure and were then incubated with CATSPER 1 antibody at final concentrations of 20,4 and 0.8μg/mL.After 1,2 and 6h incubation,progressive motility and fast progressive motility were measured by means of computer-assisted semen analysis.Results:CATSPER1 transcript was detected in both human testis and each human ejaculated semen sample.CATSPER1 protein expressed in the membrane of spermatid and was localized in the principal piece of the sperm tail.The application of CATSPER1 antibody at all concentrations significantly inhibited both progressive motility and fast progressive motility after 1,2 and 6h incubation,and significant dose-dependent changes were observed.Conclusion:CATSPER1 is meiotically and post-meiotically expressed in human testis tissue.CATSPER1 mRNA in human ejaculated spermatozoa could be a more feasible target for study and infertility screening than testis biopsy.In addition,our results suggest that human CATSPER1 could be a possible target for immunocontraception.(Asian J Androl 2006 May:8:301-306)
文摘Human spermatozoa may chemotactically find out the egg by following an increasing gradient of attractant molecules. Although human spermatozoa have been observed to show several of the physiological characteristics of chemotaxis, the chemotactic pattern of movement has not been easy to describe. However, it is apparent that chemotactic cells may be identified while returning to the attractant source. This study characterizes the pattern of movement of human spermatozoa during chemotactic re-orientation towards a progesterone source, which is a physiological attractant candidate. By means of videomicroscopy and image analysis, a chemotactic pattern of movement was identified as the spermatozoon returned towards the source of a chemotactic concentration of progesterone (10 pmol I^-1). First, as a continuation of its original path, the spermatozoon swims away from the progesterone source with linear movement and then turns back with a transitional movement that can be characterized by an increased velocity and decreased linearity. This sperm behaviour may help the spermatozoon to re-orient itself towards a progesterone source and may be used to identify the few cells that are undergoing chemotaxis at a given time.
文摘The occurrence of tyrosine phosphorylation (TP) in the sperm head during capacitation has been poorly investigated, and no data exist on the relationship of its dynamics with the acquisition of sperm fertilizing ability. This study localized TP of head proteins in human spermatozoa during capacitation and explored its relationship with acquisition of the ability to display progesterone (P)-stimulated acrosome reactions (ARs) and to penetrate zona-free hamster oocytes. By immunofluorescence, TP immunoreactivity was revealed in the acrosomal region of formaldehyde-fixed/unpermeabilized samples, whereas it was abolished in fixed/permeabilized samples, in which TP immunoreactivity was high in the principal piece. No TP immunoreaetivity was detectable in unfixed spermatozoa. Head TP immunoreactivity was localized externally to the acrosome, close to the cytoplasmic membrane, as assessed by transmission electron microscopy. The increase in head TP was an early event during capacitation, occurring within 1 h in capacitating conditions. At this time, the P-stimulated ARs were also increased, whereas egg penetration was as poor as in uncapacitated spermatozoa. At 5 h of capacitation, the extent of neither head TP nor the P-induced ARs were greater than that at 1 h, whereas egg penetration had significantly increased. Seminal plasma inhibited head TP, P-induced ARs and egg penetration. None of these inhibitory effects, unlike those on tail TP, were prevented by the cAMP analogue dbcAMP (N,2-O-dibutyryladenosine 3',5'-cyclic monophosphate). In conclusion, head TP is a subsurface event occurring early during capacitation and is closely related to acquisition of the ability to display P-stimulated ARs, whereas the ability to fuse with oolemma and to decondense is a later capacitation-related event.
文摘Aim: To study the integration of hepatitis B virus (HBV) DNA into sperm chromosomes in hepatitis B patients and the features of its integration. Methods: Sperm chromosomes of 14 subjects (5 healthy controls and 9 HB patients, including 1 acute hepatitis B, 2 chronic active hepatitis B, 4 chronic persistent hepatitis B, 2 HBsAg chronic carriers with no clinical symptoms) were prepared using interspecific in vitro fertilization between zona-free hamster oocytes and human spermatozoa. Fluorescence in situ hybridization (FISH) to sperm chromosome spreads was carried out with biotin-labeled full length HBV DNA probe to detect the specific HBV DNA sequences in the sperm chromosomes. Results: Specific fluorescent signal spots for HBV DNA were seen in sperm chromosomes of one patient with chronic persistent hepatitis B. In 9(9/42) sperm chromosome complements containing fluorescent signal spots, one presented 5 obvious FISH spots and the others 2 to 4 signals. The fluorescence intensity showed significant difference among the signal spots. The distribution of signal sites among chromosomes seems to be random. Conclusion: HBV could integrate into human sperm chromosomes. Results suggest that the possibility of vertical transmission of HBV via the germ line to the next generation is present.