Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P42574 (caspase-3)
 45,978 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To identify the mechanisms underlying capacitation, we undertook a high-resolution differential proteomic analysis of pig sperm cells. Two-dimensional gel electrophoresis and subsequent MALDI-TOF mass spectrometry analyses led to identification of 56 differentially expressed proteins. After induction of capacitation in vitro, the well-established markers of the capacitation (lactadherin P47, acrosomal protein SP-10 precursor, prohibitin, proteasomes, DJ-1 protein and arylsulfatase-A) and TCA cycle proteins (isocitrate dehydrogenase, malate dehydrogenase and pyruvate dehydrogenase) were identified. During induction, cytochrome c expression via the p53 pathway increased, however apoptotic executors, such as caspase-3, decreased significantly. Therefore, we tested the hypothesis that cytochrome c upregulation in spermatozoa is capable of activating tyrosine phosphorylation for capacitation, rather than apoptosis. Exposure of sperm cells to soluble Na2CrO4 [Cr (VI)], which induces cytochrome c upregulation, caused a dose- and time-dependent increase in tyrosine phosphorylation of sperm proteins in non-capacitating medium. In contrast, supplementation of cyclosporin A, which blocks cytochrome c upregulation, inhibited tyrosine phosphorylation of sperm proteins. Furthermore, spermatozoa in capacitation medium or non-capacitation media supplemented with soluble Cr (VI) showed similar levels of capacitation. These findings indicate that differential expression of many of these proteins has previously been unrecognized in sperm cells incubated in capacitation medium also suggest that a gradual increase of cytochrome c during incubation to induce capacitation determines sperm cell fate, i.e., apoptosis or further development for fertilization.
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PMID:Cytochrome c upregulation during capacitation and spontaneous acrosome reaction determines the fate of pig sperm cells: linking proteome analysis. 1809 29

The presence of biochemical signs of apoptosis in ejaculated spermatozoa suggests that apoptosis may be one of the pathways for sperm death. The relationship between the phosphatidylserine (PS) externalization and the presence of the active form of caspase-3 (CP-3) was studied in human spermatozoa after exposure to hydrogen peroxide (H(2)O(2)). Semen from 27 normozoospermic men was examined, as the neat semen, after swim-up isolation and after H(2)O(2) incubation, for the translocation of PS, activation of caspase-3 and mitochondrial membrane potential. The percentage of vital spermatozoa expressing PS translocation was lower than the percentage of vital spermatozoa with the active form of the caspase-3, either in neat (4.9 +/- 2.3% versus 19.7 +/- 6.2%, P < 0.001) or in swim-up semen (2.2 +/- 2.3% versus 4.8 +/- 2.9%, P < 0.01). After swim-up isolation, the percentage of vital spermatozoa with active caspase-3 decreased (P < 0.01). After H(2)O(2) stimulation of the swim-up semen fraction, a decrease in the mitochondrial membrane potential was observed (P < 0.001). Only the midpiece revealed PS translocation after H(2)O(2) stimulation, and it was also the only part to reveal the presence of the active form of caspase-3. All spermatozoa expressing the PS translocation revealed the presence of the active form of caspase-3.
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PMID:Caspase-3 activation and phosphatidylserine membrane translocation in human spermatozoa: is there a relationship? 1849 69

Apoptosis plays an essential role in normal spermatogenesis, but deregulations of this biological process, which is closely associated with male infertility, have been found. Whereas calcium homeostasis is a key regulator of cell survival, sustained elevation of intracellular calcium plays a role in apoptosis. The aim of this research was to determine the role of two different calcium mobilizing agents, hydrogen peroxide (H(2)O(2)) and the physiological agonist progesterone, on the apoptosis process of human ejaculated spermatozoa. Translocation of membrane phosphatidylserine was examined with an annexin V binding assay, DNA damage was detected by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labelling (TUNEL assay) and caspase-3 activity was assessed using a fluorometric assay. After incubation of spermatozoa for 1 h with either 10 microM H(2)O(2) or 20 microM of progesterone, there was a significant increase in both caspase-3 activity and the percentage of annexin V-positive cells. Similarly, the TUNEL results were significantly higher 1 h after incubation with either 10 microM H(2)O(2) or 20 microM of progesterone. In fact, progesterone-treated cells showed a three-fold increase (from 17.6 to 52.9%) of TUNEL-positive cells compared to untreated cells, while H(2)O(2)-treated cells exhibited a two-fold increase (from 17.6 to 37.9%). In sum, our results suggest that spermatozoa treated with calcium mobilizing agents, such as H(2)O(2) and progesterone, seem to undergo an apoptosis process that is dependent on caspase-3 activation.
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PMID:Relationship between caspase activity and apoptotic markers in human sperm in response to hydrogen peroxide and progesterone. 1973 95

Maintaining the integrity of sperm DNA is vital to reproduction and male fertility. Sperm contain a number of molecules and pathways for the repair of base excision, base mismatches and DNA strand breaks. The presence of Poly (ADP-ribose) polymerase (PARP), a DNA repair enzyme, and its homologues has recently been shown in male germ cells, specifically during stage VII of spermatogenesis. High PARP expression has been reported in mature spermatozoa and in proven fertile men. Whenever there are strand breaks in sperm DNA due to oxidative stress, chromatin remodeling or cell death, PARP is activated. However, the cleavage of PARP by caspase-3 inactivates it and inhibits PARP's DNA-repairing abilities. Therefore, cleaved PARP (cPARP) may be considered a marker of apoptosis. The presence of higher levels of cPARP in sperm of infertile men adds a new proof for the correlation between apoptosis and male infertility. This review describes the possible biological significance of PARP in mammalian cells with the focus on male reproduction. The review elaborates on the role played by PARP during spermatogenesis, sperm maturation in ejaculated spermatozoa and the potential role of PARP as new marker of sperm damage. PARP could provide new strategies to preserve fertility in cancer patients subjected to genotoxic stresses and may be a key to better male reproductive health.
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PMID:Potential biological role of poly (ADP-ribose) polymerase (PARP) in male gametes. 1996 17

This study investigates the effects of glycerol, 1,2 propanediol, sucrose, and trehalose on post-thaw motility, morphology, and genome integrity of Awassi ram semen. Ejaculates of thick consistency with rapid wave motion (>+++) and >70% initial motility were pooled. Sperm were diluted to a final concentration of 1/5 (semen/extender) in 0% cryoprotectant, 6% glycerol, 6% 1,2 propanediol, 62.5 mM sucrose or 62.5 mM trehalose using a two-step dilution method. The equilibrated semen was frozen in 0.25-ml straws. Semen samples were examined for sperm motility, defective acrosomes (FITC-Pisum sativum agglutinin (FITC PSA)), DNA integrity (acridine orange staining (AO)) and apoptotic activity (terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) and Caspase-3 activity) at four time points: after dilution with extender A, after cooling to 5 degrees C, after equilibration and post-thaw. Freezing and thawing procedures (cooling at 5 degrees C, dilution, equilibration, and thawing) had negative effects on motility (P<0.001), acrosome integrity (P<0.001), and DNA integrity as determined by AO (P<0.001) and TUNEL (P<0.001) assays. There were positive correlations between sperm with defective acrosomes and apoptotic (AO- and TUNEL-positive) spermatozoa. In contrast, a significant negative correlation was found between sperm motility and defective acrosomes and AO- and TUNEL positivity (P<0.01). The cryopreservation process acts as an apoptotic inducer in ram semen; all cryoprotectants used in the present study allowed apoptosis to some extent, with negative effects on sperm morphology and DNA integrity. The glycerol group performed better than the propanediol, sucrose, trehalose, and control groups in terms of post-thaw sperm motility but not DNA integrity.
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PMID:Effects of different cryoprotective agents on ram sperm morphology and DNAintegrity. 2017

The inclusion of apoptotic spermatozoa during assisted reproductive techniques (ART) may be one reason for suboptimal success rates. The aim of our study was to evaluate the potential of routine semen preparation to eliminate spermatozoa with activated apoptosis signalling. Semen samples from 20 infertility patients scheduled for ART procedures were investigated. Following density gradient centrifugation (DGC) and swim-up, aliquots were taken from each sample to analyse motility, Caspase-3 activation (CP3) and integrity of the mitochondrial membrane potential (MMP) using flow cytometry. Aliquots from the neat semen served as controls. Semen samples of patients contained 53.8 +/- 17.7% spermatozoa with disrupted MMP and 51.8 +/- 14.9% with active CP3. Preparation by DGC and swim-up resulted in improvement of progressive motility (+43.5%) and reduction of spermatozoa with disrupted MMP (-34.3%) and activated CP3 (-25.7%, P < 0.01). Minimal reduction of spermatozoa with disrupted MMP and active CP3 was 6.0% and 0.7%, maximum reduction was 65.5% (disrupted MMP) and 49.3% (CP3). Semen samples of subfertile patients contain high levels of spermatozoa with activated apoptosis signalling. Although there was a reduction in the majority of the samples, profound interindividual differences in the separation effect demand further development of innovative molecular-based separation methods to deplete apoptotic spermatozoa.
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PMID:Effects of post-density gradient swim-up on apoptosis signalling in human spermatozoa. 2038 4

Nitric oxide (NO) is known to be involved in multiple signal transduction pathways of male germ cells, including sperm capacitation. In somatic cells, NO production was found to be part of apoptosis signalling. The aim of our study was to further clarify the role of NO in spermatozoa by investigation of NO synthase activity with regard to sperm maturity and sperm apoptosis signalling. Semen specimens from 19 healthy donors were subjected to density gradient centrifugation to separate the predominantly mature and immature sperm fraction. NO synthase activity was evaluated using diaminofluoresceine-2-diacetate by FACS. Apoptosis signalling was monitored by flowcytometric analyses of caspase-3 (CP3) and integrity of the transmembrane mitochondrial potential (TMP). TUNEL assay was used to detect DNA fragmentations. Maturity of human spermatozoa was associated with increased NO synthase activity and inactivated apoptosis signalling (lower levels of disrupted TMP, active CP3 and DNA fragmentations, P < 0.05). Activation of apoptosis signalling was significantly negatively correlated to NO production, indicating a rather anti-apoptotic effect of NO. This might underline the recently proposed role of NO in physiological sperm signal transduction, e.g. during capacitation.
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PMID:Activity of nitric oxide synthase in mature and immature human spermatozoa. 2038 5

Spermatozoa mediated gene transfer has become a promising technology to generate transgenic animals with disease resistance. However, exogenous DNA invasion may cause changes in spermatozoon natural defense system which result in spermatozoon dysfunction.The objective of this study was to investigate the changes of mitochondrial function and motility in goat spermatozoa after pre-incubation and incubation with and without the human lysozyme plasmid pFLAG-hLY. The results demonstrated that human lysozyme plasmid pFLAG-hLY could bind to the surface of the spermatozoon membrane at 186,000 copies/spermatozoa and incorporate to spermatozoon nucleus at 78 copies/spermatozoa after incubation. However, the treated spermatozoon samples showed a significant lower motility (29.7+/-2.2% vs. pre-incubation control 48.0+/-1.4% and incubation control 54.5+/-1.5%, P < 0.05), and percentage of rapid progressive motile spermatozoa(16.4+/-2.4% vs. pre-incubation control 31.4+/-0.6% and incubation control 37.0+/-0.5%,P < 0.01). Meanwhile, the incubation with plasmids caused significant reduction of mitochondrial membrane potential (31.44+/-2.17% vs. pre-incubation control 51.79+/-2.08% and incubation control 58.81+/-1.76%, P < 0.05). In addition, dichlorofluorescin relative fluorescence intensity (32.81+/-2.41%) and malondialdehyde levels (2.18+/-0.21 nM/108 spermatozoa), which represents mitochondrial function, showed a significant increase after incubation (P < 0.05). The cytochrome c release from the mitochondrial inner membrane space, and enzymatic activities of caspase-3 (0.086+/-0.024) and caspase-9 (0.083+/-0.019)(P < 0.05) also increased, in which resulted in spermatozoon dysfunction. In conclusion, this study confirmed that goat spermatozoa could capture human lysozyme plasmid pFLAG-hLY,but the incubation with the plasmids resulted in a decrease of spermatozoa motility and partial rupture of mitochondrial membrane, and further prompted the expression of cytochrome c, and generation of oxidative stress in vitro and finally led to spermatozoon dysfunction.
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PMID:Alterations in mitochondrial function and spermatozoal motility in goat spermatozoa following incubation with a human lysozyme plasmid. 2063 54

Abstract Recent reports suggest that mobile phone radiation may diminish male fertility. However, the effects of this radiation on human spermatozoa are largely unknown. The present study examined effects of the radiation on induction of apoptosis-related properties in human spermatozoa. Ejaculated, density-purified, highly motile human spermatozoa were exposed to mobile phone radiation at specific absorption rates (SARs) of 2.0 and 5.7 W/kg. At various times after exposure, flow cytometry was used to examine caspase 3 activity, externalization of phosphatidylserine (PS), induction of DNA strand breaks, and generation of reactive oxygen species. Mobile phone radiation had no statistically significant effect on any of the parameters studied. This suggests that the impairment of fertility reported in some studies was not caused by the induction of apoptosis in spermatozoa.
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PMID:Mobile phone radiation does not induce pro-apoptosis effects in human spermatozoa. 2068 83

Previously, we have purified three distinct DNases from spermatozoa of sea urchin Strongylocentrotus intermedius and we suppose the role of Ca(2+), Mg(2+)-dependent DNase (Ca, Mg-DNase) in apoptosis of spermatozoa. Two-headed sphingolipid rhizochalin (Rhz) induced characteristic apoptotic nuclear chromatin changes, internucleosomal DNA cleavage, and activation of caspase-9, caspase-8, and caspase-3 in spermatozoa as was shown by fluorescence Hoechst 33342/PI/FDA analysis, DNA fragmentation assay, and fluorescence caspase inhibitors FAM-LEHD-fmk, FAM-IETD-fmk, and FAM-DEVD-fmk, respectively. Inhibitor of caspase-3 z-DEVD-fmk subdued Rhz-induced internucleosomal ladder formation, which confirmed the major role of caspase-3 in apoptotic DNA cleavage probably through Ca, Mg-DNase activation. Participation of sea urchin Ca, Mg-DNase in apoptosis of spermatozoa was demonstrated by ions Zn(2+) blocking of Rhz-induced DNA fragmentation due to direct inhibition of the Ca, Mg-DNase and internucleosomal cleavage of HeLa S and Vero E6 cell nuclei chromatin by highly purified Ca, Mg-DNase.
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PMID:Ca2+, Mg2+-dependent DNase involvement in apoptotic effects in spermatozoa of sea urchin Strongylocentrotus intermedius induced by two-headed sphingolipid rhizochalin. 2093 97


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