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M Morshedi

Publications and source records attributed to M Morshedi.

At least 19 recordsLinked to original sources
PubMed2006

Testis/sperm-specific histone 2B in the sperm of donors and subfertile patients: variability and relation to chromatin packaging.

BACKGROUND: The compaction of human sperm chromatin is the result of replacement of approximately 85% of histones with protamines. Germ-line testis/sperm-specific histone 2B (TSH2B) has been detected in only approximately 30% of mature spermatozoa. Its level in the semen of subfertile patients varies; its function is unknown. We evaluated TSH2B in the sperm samples of 23 donors and 49 subfertile patients and assessed its association with chromatin compaction status. METHODS: TSH2B level was measured using immunoblotting. Chromatin packaging quality was evaluated by staining with chromomycin A3 (CMA3) which marked spermatozoa with defective packaging. To assess both TSH2B and chromatin status in the same spermatozoon, CMA3 staining and TSH2B immunolocalization were performed sequentially. RESULTS: A significant correlation (r = 0.55, P = 0.0027) was found between TSH2B level and percentage of CMA3-positive sperm in patient and donor semen samples. When individual spermatozoa were assessed for these parameters, 92% of TSH2B-containing cells were also CMA3 positive. Variation in the total sperm TSH2B level was less in donors than in patients. CONCLUSIONS: CMA3 positive staining of TSH2B-containing individual spermatozoa and a significant correlation between the total TSH2B level and CMA3 percentage in semen samples suggest a structural role for TSH2B in sperm chromatin organization. Low variability of TSH2B level in donors implies a mechanism (however unknown) regulating this parameter.

Chromatin↗
PubMed2002

Sperm DNA quality predicts intrauterine insemination outcome: a prospective cohort study.

BACKGROUND: We aimed to investigate whether sperm DNA quality may predict intrauterine insemination (IUI) outcome. METHODS: The study was designed in a prospective cohort fashion, at a tertiary centre for reproductive medicine. A total of 119 patients underwent 154 cycles of IUI. Parameters related to demography, cycle management and semen sample used for IUI were evaluated. Conventional semen parameters, morphology (strict criteria), sperm DNA fragmentation and stability [evaluated by terminal deoxynucleotidyl transferase-mediated dUDP nick-end labelling (TUNEL) and acridine orange staining under both acid and acid + heat denaturing conditions respectively] were measured. The main outcome measure was clinical pregnancy, defined as ultrasonographic visualization of intrauterine gestational sac(s). RESULTS: Logistic regression analyses were done on six sets of data, including all cycles combined, cycles with washed samples, first cycle of each couple, first cycle of each couple with washed samples, cycles stimulated with gonadotrophins and finally gonadotrophin-stimulated cycles with washed samples. The number of pre-ovulatory follicles on day of hCG, the age of the woman and the percentage of sperm with acid- + heat-resistant DNA were the parameters that predicted IUI outcome in most of these data subsets. For the gonadotrophin-stimulated cycles, age of the man appeared as a predictor as opposed to that of the woman; and for the cycles within this subgroup, where the semen sample was washed, sperm DNA fragmentation and age of the man were the only two parameters to predict IUI outcome. No samples with >12% of sperm having DNA fragmentation resulted in pregnancy. CONCLUSIONS: The number of follicles, age of the woman/man and sperm DNA quality may predict IUI outcome.

Adult↗
PubMed2001

Cryopreservation-thawing of fractionated human spermatozoa and plasma membrane translocation of phosphatidylserine.

OBJECTIVE(S): [1] To evaluate sperm membrane damage during cryopreservation-thawing by the assessment of phosphatidylserine (PS) translocation and [2] to examine the relationship between reactive oxygen species (ROS) and cryopreservation-related alterations. DESIGN: Prospective cohort study. SETTING: University-based center. PATIENT(S): Men consulting for infertility and fertile donors (controls). INTERVENTION(S): Semen processing was performed by density gradient separation followed by cryopreservation and thawing. MAIN OUTCOME MEASURE(S): Membrane PS translocation was evaluated with annexin V binding, generation of ROS was detected by chemiluminescence, and motion parameters were assessed by computer analysis. RESULT(S): Annexin V binding was detected in the prefreeze fractions with high and low sperm motility. In the patient group, there were significantly higher postthaw levels of annexin V binding in both fractions when compared with prefreezing values. However, such induction of PS translocation was significantly higher in the fractions with high sperm motility. Significantly higher ROS levels were detected in prefreeze samples of the fractions with low sperm motility. CONCLUSION(S): In the population of men studied, [1] cryopreservation-thawing was associated with induction of membrane PS translocation; [2] postthaw ROS levels were lower than before freezing; and [3] neither annexin V binding results nor the generation of ROS were able to accurately predict sperm cryosurvival rates.

Annexin A5↗
PubMed2001

Outcome of intracytoplasmic sperm injection in azoospermic patients: stressing the liaison between the urologist and reproductive medicine specialist.

OBJECTIVES: To analyze the outcome of intracytoplasmic sperm injection (ICSI) cycles in infertile couples in whom the main diagnosis of infertility was azoospermia of obstructive and nonobstructive origin. METHODS: Eighty-three consecutive ICSI cycles were carried out with retrieved testicular or epididymal spermatozoa, 60 cycles in 32 patients with obstructive azoospermia and 23 cycles in 12 patients with nonobstructive azoospermia. Fifty-four testicular biopsies (testicular sperm extraction) and 18 epididymal aspirations (microepididymal sperm aspiration) were performed.Results. Motile spermatozoa were recovered in 65 cycles (90.3%). In another 3 (4.2%), nonmotile spermatozoa were retrieved. In 4 patients (5.5%), sperm could not be recovered. In 11 cycles, frozen sperm from a previous procedure were used. A significantly lower fertilization rate (64% versus 73%, P = 0.02), clinical pregnancy rate (13% versus 47%, P <0.001), and good embryo quality rates (35% versus 56%, P = 0.009) were observed in patients with nonobstructive azoospermia. In patients with obstructive azoospermia, no significant differences were observed when the outcome was analyzed on the basis of the sperm origin (ie, from testicular sperm extraction or microepididymal sperm aspiration). CONCLUSIONS: When combining testicular sperm extraction or microepididymal sperm aspiration with ICSI in patients with obstructive azoospermia, the results in terms of fertilization, implantation, and pregnancy rates were similar to those found in patients with nonazoospermic obstruction who underwent ICSI with ejaculated sperm. Patients with nonobstructive azoospermia had lower fertilization, embryo quality, and pregnancy rates than did those with obstructive azoospermia, probably because of severe defects in spermatogenesis, leading to poor gamete quality. The urologist and reproductive endocrinologist now have an excellent therapeutic option to offer men with previously intractable infertility.

Adult↗
PubMed2001

Cryopreservation of fractionated, highly motile human spermatozoa: effect on membrane phosphatidylserine externalization and lipid peroxidation.

INTRODUCTION: This study investigated lipid peroxidation (LPO) and membrane integrity following cryopreservation-thawing. METHODS: Infertile men (study group) and donors (control group) were examined. Purified populations of highly motile spermatozoa were cryopreserved using TEST-yolk buffer and glycerol (TYB-G) followed by quick thaw. LPO was measured by a spectrophotometric assay, with and without a ferrous ion promoter. Annexin V binding was used to assess membrane translocation of phosphatidylserine (PS). RESULTS: Pre-freeze LPO was significantly higher in the study than in the control group (P = 0.03). In both groups, LPO measurements after thawing were significantly higher than the pre-freeze samples not exposed to TYB-G (P = 0.002 and P = 0.001 respectively). However, when the pre-freeze samples with TYB-G were compared with the post-thaw samples (all exposed to TYB-G), these differences were not significant. There was a significant increase in PS externalization following cryopreservation in both groups (P = 0.02 and P = 0.003 respectively). In donors, pre-freeze LPO concentrations had a significant positive correlation with thawed spermatozoa depicting PS externalization (r = 0.77, P = 0.04). CONCLUSION: Although patients had higher basal LPO than donors, LPO did not differ between fresh and cryopreserved-thawed fractionated motile spermatozoa. Freezing-thawing was associated with translocation of PS to the external membrane leaflet.

Biological Transport↗
PubMed2000

Assessment of sperm cryodamage and strategies to improve outcome.

Sperm cryopreservation still represents a valuable clinical aid in the management of infertility. Its current principal indications include (1) donor sperm insemination; (2) freezing before cancer therapy to maintain reproductive capacity; (3) patient's convenience; and (4) because of the outstanding success with ICSI, even patients with different degrees of oligo-asthenoteratozoospermia can now be offered the use of frozen/thawed sperm for oocyte micromanipulation. Although sperm cryopreservation/thawing and results of insemination and IVF have been consistently good using donor semen, results of infertile men (with or without various degrees of oligoasthenoteratozoospermia) have yielded remarkably lower rates of survival and pregnancy. Freezing/thawing techniques have not been subjected to major changes in the last years, Furthermore, the exact nature of sperm cryodamage still remains to be elucidated. Various aspects of sperm freezing are revisited here (1) development of new technical approaches for cryopreservation; (2) analysis of the stimulatory effect of putative cryoprotectant additives; (3) the use of intrauterine insemination-ready processed samples; and (4) selection and optimization of end-points for analysis of cryodamage. It is expected that advances in such areas will improve significantly the cryopreservation/thawing outcome particularly as related to semen samples of subfertile men.

Cryopreservation↗
PubMed2000

Semen treatment with progesterone and/or acetyl-L-carnitine does not improve sperm motility or membrane damage after cryopreservation-thawing.

OBJECTIVE: To assess the effects of progesterone and acetyl-L-carnitine used before semen cryopreservation-thawing on sperm motility parameters and plasma membrane integrity. DESIGN: Prospective cohort study. SETTING: Academic tertiary center. PATIENT(S): Subfertile men undergoing semen evaluation. INTERVENTION(S): Before cryopreservation, spermatozoa were incubated with water-soluble progesterone (1 and 10 microM), acetyl-L-carnitine (2.5, 5, 10, and 20 mM), or both (progesterone, 1 microM; and acetyl-L-carnitine, 5 mM). MAIN OUTCOME MEASURE(S): Postthaw change of motility parameters (computer-assisted measurements) and vitality-membrane integrity (examined with eosin-Y staining and annexin V-Cy3 binding assay). RESULT(S): There were no statistically significant differences between control samples and samples treated with progesterone and/or acetyl-L-carnitine for cryosurvival rate, motility parameters, or membrane integrity. The percentages of postthaw cells identified as live showed significantly different results with use of the eosin-Y staining and annexin V binding assay. CONCLUSION(S): Neither progesterone nor acetyl-L-carnitine seemed to prevent cryodamage assessed by motility changes or membrane integrity in human spermatozoa of subfertile men. Annexin V binding, a reflection of membrane translocation of phosphatidylserine, provided more distinct information about postfreezing membrane integrity changes than eosin-Y staining.

Acetylcarnitine↗
PubMed2000

Effects of hydrogen peroxide on DNA and plasma membrane integrity of human spermatozoa.

OBJECTIVE: To evaluate the effects of oxidative stress on DNA and plasma membrane integrity of human spermatozoa. DESIGN: Prospective cohort study. SETTING: University-based, tertiary-care infertility center. PATIENT(S): Men (n = 10) undergoing infertility investigation. INTERVENTION(S): Purified populations of sperm with high motility were separated using Percoll density gradients. Then, spermatozoa were incubated with 0, 10, 100, and 200 microM hydrogen peroxide (H(2)O(2)) under capacitating conditions. MAIN OUTCOME MEASURE(S): Motion parameters were assessed by computer analysis. Genomic integrity was examined by the terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end-labeling (TUNEL) assay. Plasma membrane integrity was evaluated by the annexin V-binding assay, a measure of phosphatidylserine translocation. RESULT(S): Under basal conditions, there was a significant and negative relationship between sperm motility and the percentages of sperm with DNA fragmentation and membrane translocation of phosphatidylserine. After a 2-h incubation, there was a significant, dose-dependent effect of H(2)O(2) on motion parameters (decrease) and DNA fragmentation (increase). The percentage of annexin V(-) live (normal) cells declined significantly as the level of oxidative stress increased. Although the percentages of annexin V(+) live cells (sperm depicting translocation of phosphatidylserine) and necrotic cells increased at the highest H(2)O(2) levels, these changes were not significant. CONCLUSION(S): In vitro sperm incubation with H(2)O(2) induces DNA fragmentation in a dose-dependent fashion. The sublethal effects of oxidative stress on motion parameters were not significantly associated with membrane translocation of phosphatidylserine.

Annexin A5↗
PubMed2000

Analysis of DNA fragmentation, plasma membrane translocation of phosphatidylserine and oxidative stress in human spermatozoa.

UNLABELLED: The objectives of this cross-sectional observational study were: (i) to detect DNA damage and plasma membrane translocation of phosphatidylserine in purified sperm populations of high and low motility, and (ii) to analyse their relationship with the endogenous generation of reactive oxygen species. Ejaculates from infertile men were examined following gradient centrifugation. The main outcome measures were: sperm motion parameters (assessed with a computer analyser), generation of reactive oxygen species (measured by chemiluminescence), DNA damage (detected by terminal deoxynucleotidyl transferase-mediated dUDP nick-end labelling and monoclonal antibody labelling of single-stranded DNA) and translocation of membrane phosphatidylserine (examined with annexin V staining). DNA fragmentation and membrane translocation of phosphatidyl-serine were observed in the fractions with low and high sperm motility in all patients. The fractions with low sperm motility had significantly higher proportion of cells with DNA damage and production of reactive oxygen species than the fractions with high sperm motility (P < 0.005). DNA fragmentation was significantly and positively correlated with the generation of reactive oxygen species (r = 0.42; P = 0.02). IN CONCLUSION: (i) spermatozoa from infertile men display translocation of membrane phosphatidylserine as diagnosed by annexin V positive staining; (ii) DNA damage (fragmentation and presence of single-stranded DNA) can be detected in ejaculated spermatozoa from infertile men in fractions with low and high sperm motility, and (iii) there is a relationship between DNA damage and oxidative stress.

Adult↗
PubMed1999

Modulation of sperm tail protein tyrosine phosphorylation by pentoxifylline and its correlation with hyperactivated motility.

OBJECTIVE: To assess the effect of pentoxifylline on human sperm functions that are crucial to fertilization. DESIGN: Prospective, controlled study. SETTING: Academic tertiary care institute. PATIENT(S): Healthy male sperm donors. INTERVENTION(S): The effects of pentoxifylline (3.6 mM) on hyperactivated motility, sperm binding to the zona pellucida, and sperm protein tyrosine phosphorylation were evaluated. MAIN OUTCOME MEASURE(S): Hyperactivated motility was assessed by computer-assisted motion analysis, and tight binding of sperm to homologous zonae pellucidae was examined using the hemizona assay. Sperm protein phosphorylation was evaluated using indirect immunofluorescence with an antibody to phosphotyrosine (PY20). RESULT(S): Pentoxifylline significantly stimulated hyperactivated motility at 1 hour and 4 hours; it also significantly increased sperm binding to the zona pellucida and enhanced sperm tail tyrosine phosphorylation at 4 hours under capacitating conditions. There was a statistically significant correlation between hyperactivated motility and sperm tail protein phosphorylation. CONCLUSION(S): Pentoxifylline stimulates sperm functions that are essential to achieving fertilization under in vitro conditions in sperm obtained from fertile men. The enhancement of hyperactivated motility is associated with the stimulation of sperm tail tyrosine phosphorylation, suggesting a causal relation and the involvement of a modulatory effect after cyclic adenosine monophosphate-dependent phosphorylation of intermediate proteins.

Fertilization in Vitro↗
PubMed1999

Pentoxifylline stimulates various sperm motion parameters and cervical mucus penetrability in patients with asthenozoospermia.

Pentoxifylline (PTX) was incubated in vitro with human spermatozoa to examine its effects on sperm motility characteristics and bovine cervical mucus penetrability (BCMP). Sperm motion parameters were assessed by computer-assisted motion analysis (CASA) using HTM-IVOS and BCMP was evaluated using the Penetrak kit. In vitro incubation with PTX (1 mg ml-1; 3.6 mM, 30 min) did not significantly change percentage motility, average path velocity (VAP), straight-line velocity (VSL) or beat cross frequency (BCF) of spermatozoa from normozoospermic or asthenozoospermic samples. However, it significantly increased curvilinear velocity (VCL), amplitude of lateral head displacement (ALH) and hyperactivated motility (HA), and significantly decreased linearity (LIN) of spermatozoa from both samples. Pentoxifylline was found to increase BCMP scores for spermatozoa from asthenozoospermic samples, but did not affect scores for spermatozoa from normozoospermic samples. Bovine cervical mucus penetrability (BCMP) was found to be positively and significantly correlated with the percentage motility of both non-PTX-treated and PTX-treated spermatozoa for asthenozoospermic samples. These results demonstrated that PTX enhanced several motion sperm parameters as well as BCMP in asthenozoospermic samples and suggest a potential use of the methylxanthine in infertile patients with motility defects undergoing artificial insemination.

Animals↗
PubMed1999

Intra- and inter-laboratory variability in the assessment of sperm morphology by strict criteria: impact of semen preparation, staining techniques and manual versus computerized analysis.

We designed prospective studies to compare manual and computerized analysis of sperm morphology by strict criteria using different semen processing and staining techniques. A total of 54 semen samples were studied; slides were prepared from each subject from liquefied semen and after washing, and stained with Diff-Quik or Papanicolaou. An intra-laboratory, blind assessment was performed manually (two observers) and using a computerized analyser (two readings). This demonstrated a very good correlation between manual analysis of liquefied and washed samples with both staining techniques [intraclass coefficient (ICC) = 0.93 and 0.83]. Greater agreement was observed between computerized readings (washed samples) of Diff-Quik (ICC = 0.93) than of Papanicolaou-stained slides (ICC = 0.66). An excellent intra-laboratory correlation was observed for within-computer readings (ICC = 0.93). There was moderate agreement between inter-laboratory computer readings (two centres, ICC = 0.72). Although there was lower inter-laboratory agreement for manual and manual versus computer readings, overall results of all manual and computer analyses showed good agreement (ICC = 0.73). Diff-Quik staining is reliable for both manual (liquefied) and computer (washed) analysis of strict sperm morphology. Intra- and inter-computer analyses using this method reached satisfactory levels of agreement. There is still high inter-laboratory variability for the manual method.

Adult↗
PubMed1998

Increase of intracellular calcium is not a cause of pentoxifylline-induced hyperactivated motility or acrosome reaction in human sperm.

OBJECTIVE: To investigate the effects of the phosphodiesterase inhibitor pentoxifylline on hyperactivated motility and acrosome reaction in human sperm and to determine whether its stimulatory effects occur via increased intracellular calcium levels. DESIGN: Prospective study. SETTING: Academic tertiary care facility. PARTICIPANT(S): Healthy male donors. INTERVENTION(S): The effects of pentoxifylline on hyperactivated motility, acrosome reaction, and intracellular calcium were studied and compared with the effects of progesterone. Thapsigargin, a known mobilizer of intracellular calcium, also was used as positive control. MAIN OUTCOME MEASURE(S): Hyperactivated motility was assessed by computer-assisted sperm motion analysis using the HTM-IVOS, acrosome reaction was evaluated with the fluorescent probe fluorescein isothiocyanate-labeled Pisum sativum agglutinin, and intracellular calcium was determined by fura-2 using spectrofluorometry. RESULT(S): Pentoxifylline significantly increased both hyperactivated motility and acrosome reaction. Enhancement of hyperactivated motility by pentoxifylline in the capacitation medium persisted for up to 5 hours after pentoxifylline was washed from the medium. It also enhanced the percentage of acrosome-reacted spermatozoa after 4 hours of incubation. These effects occurred in the presence of a marginally significant decrease in intracellular calcium. CONCLUSION(S): Pentoxifylline stimulates hyperactivated motility and acrosome reaction in spermatozoa from fertile men. Its stimulatory effects occur through mechanism(s) other than increase in intracellular calcium.

Acrosome↗
PubMed1998

Plasma membrane integrity of cryopreserved human sperm: an investigation of the results of the hypoosmotic swelling test, the water test, and eosin-Y staining.

OBJECTIVE: [1] To examine the relationship between sperm membrane integrity and motion parameters before and after cryopreservation; [2] to determine the capacity of the membrane integrity tests to predict the outcome of cryopreservation in fertile and infertile men; and [3] to examine the degree of agreement between tail and head membrane integrity of testicular and ejaculated immotile sperm cryopreserved for intracytoplasmic sperm injection. DESIGN: Prospective study. SETTING: Academic tertiary care institution. PATIENT(S): Fertile donors and normozoospermic oligozoospermic, and asthenozoospermic subfertile men. INTERVENTION(S): Semen samples were cryopreserved and thawed for analysis. MAIN OUTCOME MEASURE(S): Sperm membrane integrity and computer-assisted motion parameters. RESULT(S): The hypoosmotic swelling test and water test had a significant and positive correlation in the fresh and cryopreserved ejaculates of all groups. The results of the hypoosmotic swelling test correlated positively with the percent motility in the fresh ejaculates of fertile and subfertile men. None of the membrane integrity tests correlated with the cryosurvival rate in any group. In the ejaculated and testicular samples with no postcryopreservation motility, the simultaneous assessment of hypoosmotic swelling test and eosin showed that of 33% sperm exhibiting coiling with the hypoosmotic swelling test, only 9% were eosin negative, whereas 24% were eosin positive. CONCLUSION(S): [1] The water test may be a simpler replacement for the hypoosmotic swelling test; [2] none of the membrane integrity tests predicted sperm motility after cryopreservation; and [3] there was a high degree of disagreement between the hypoosmotic swelling test and eosin in the samples with no postcryopreservation motility.

Cell Membrane↗
PubMed1998

Comparison of various methods of processing human cryopreserved-thawed semen samples.

We compared the efficacy of various methods of processing cryopreserved-thawed samples for the recovery of functionally adequate spermatozoa as assessed by the response to the sperm stress test (SST), an index of temperature activated sperm membrane lipid peroxidation, and immediate and delayed changes in sperm viability and motion parameters. Donor semen samples (n = 28) were cryopreserved-thawed and divided into six equal parts, one part was used as control and the remaining parts were used to compare five methods of sperm processing as follows: direct Percoll gradient processing, washing by one-step or stepwise addition of the washing medium followed by Percoll processing, and washing by one-step or stepwise addition of the washing medium. Additional samples (n = 10) were evaluated for the immediate and delayed (6 h at 37 degrees C) impact of one-step and stepwise washing (without Percoll separation). Compared with wash-only methods, samples processed using Percoll had a significantly higher SST score (P = 0.001), motility, rapid spermatozoa (>50 microm/s), curvilinear velocity and motility index (P < 0.001). Comparing various Percoll methods, direct Percoll processing resulted in the highest number of motile spermatozoa recovered (P < 0.00001) and a higher SST score based on curvilinear velocity (P = 0.001). Stepwise washing gave a significantly higher number of motile spermatozoa (P < 0.001) but with a significantly lower SST score based on the concentration of motile spermatozoa (P = 0.001), motility (P = 0.001) and motility index (P = 0.01). Sperm viability and motion parameters after 6 h of incubation showed no difference between one-step and stepwise washing. In conclusion, compared with wash-only methods, Percoll processed samples resulted in the recovery of spermatozoa with superior quality as assessed by SST and motion analysis. One-step washing of the samples gave an overall comparable recovery compared to the samples prepared stepwise. Having significantly higher SST scores, similar viability and the maintenance of motility, one-step washing may be a better method of processing thawed samples than the stepwise washing.

Cell Survival↗
PubMed1998

Semen quality: is there a paternal effect on pregnancy outcome in in-vitro fertilization/intracytoplasmic sperm injection?

The objective of this study was to investigate the role of the spermatozoon (paternal effects) on implantation and pregnancy outcome in in-vitro fertilization/intracytoplasmic sperm injection (IVF/ICSI). Male individuals of three types were analysed: infertile men with oligoasthenoteratozoospermia (OAT), infertile men with normozoospermia and fertile men (donors). Female counterparts were judged to have comparable egg quality within two groups studied, i.e. infertile women with pure mechanical (tubal) infertility and recipients of donor eggs. There were significantly higher differences in implantation and pregnancy rates in groups using donor spermatozoa and donor egg recipients. Analyses of key set groups revealed a trend toward a poorer implantation and pregnancy outcome when comparing OAT versus normozoospermic patients within IVF, but not within ICSI treatments, in couples with tubal infertility. In couples who were recipients of donor eggs, no differences were observed between OAT patients treated by ICSI and normozoospermic patients treated with IVF. No significant differences were observed in miscarriage rates within any groups studied. In conclusion, the poorer results observed in OAT patients undergoing IVF may be secondary to spermatozoal effects due to a high insemination concentration. Overall, there does not seem to be a significant effect of severe male infertility (OAT) on implantation and pregnancy outcome. However, this does not preclude that specific sperm aberrations may exert a negative effect on embryogenesis and therefore on implantation potential following assisted or in-vivo reproduction.

Adult↗
PubMed1995

Investigation of some biochemical and functional effects of cryopreservation of human spermatozoa using an automated freezing-quick-thawing method.

The objective of the present studies was to assess the functional integrity of the sperm plasma membrane and metabolic and motility characteristics of the recovered motile fraction of human spermatozoa subjected to an automated freezing/quick-thawing method. Sperm membrane features examined included progesterone-induced changes in intracellular levels of calcium ([Ca2+]i), as measured by the fluorescent fura-2 indicator, and the tight binding of spermatozoa to homologous zonae pellucidae as assessed by the hemizona assay (HZA). Basal [Ca2+]i intracellular adenosine triphosphate (ATP) and adenosine diphosphate (ADP) levels determined using chemiluminescence with luciferin-luciferase, and motility parameters determined using a computer-aided semen analyser (CASA) were studied concomitantly as an expression of metabolic/functional status. Ejaculates from fertile men (donors) were evaluated after swim-up separation of the motile fraction in both fresh and cryopreserved-thawed samples, and fractions of each ejaculate (fresh and frozen-thawed) were subjected to parallel measurements of the same parameters at the same time frame. Basal and progesterone-induced increase in [Ca2+]i, and ATP levels (up to 24 h) were similar in fresh and frozen-thawed samples. HZA results showed a modest (26%) although significant (p = 0.008) decrease in binding in frozen-thawed samples. The ratios of ATP/ADP in fresh and frozen-thawed samples were also found to be similar. Although post-thaw sperm motility was significantly lower than that of the fresh samples, comparison of the results indicated that the method was capable of preserving > 65% of motile spermatozoa in almost all of the samples cryopreserved. Additionally, the swim-up rescued a motile fraction in the frozen-thawed samples that was not significantly impaired with regard to motility, mean linear velocity or linearity as compared to the fresh fractions in the first 4 h. Our results show that this automated freezing-quick-thawing method results in a small reduction in sperm-zona binding capacity, and that the time-dependent decline in motility parameters observed for both fresh and cryopreserved-thawed samples cannot be related to ATP deficiency under the conditions of our experiments. These in-vitro results are coincident with the maintenance of fertilizing capacity for donor spermatozoa in the in-vitro fertilization (IVF) setting.

Adenosine Diphosphate↗