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Sperm DNA (sperm + dna)
Kinds of Sperm DNA Terms modified by Sperm DNA Selected AbstractsEffect of Alcohol Consumption on CpG Methylation in the Differentially Methylated Regions of H19 and IG-DMR in Male Gametes,Implications for Fetal Alcohol Spectrum DisordersALCOHOLISM, Issue 9 2009Lillian A. Ouko Background:, Exposure to alcohol in utero is the main attributable cause of fetal alcohol spectrum disorders (FASD) which in its most severe form is characterized by irreversible behavioral and cognitive disability. Paternal preconception drinking is not considered to be a significant risk factor, even though animal studies have demonstrated that chronic paternal alcohol consumption has a detrimental effect on the physical and mental development of offspring even in the absence of in utero alcohol exposure. It has been documented that alcohol can reduce the levels and activity of DNA methyltransferases resulting in DNA hypomethylation and that reduced methyltransferase activity can cause activation of normally silenced genes. The aim of this study was to establish a link between alcohol use in men and hypomethylation of paternally imprinted loci in sperm DNA in genomic regions critical for embryonic development, thus providing a mechanism for paternal effects in the aetiology of FASD. Methods:, Sperm DNA from male volunteers was bisulfite treated and the methylation patterns of 2 differentially methylated regions (DMRs), H19 and IG-DMR, analyzed following sequencing of individual clones. The methylation patterns were correlated with the alcohol consumption levels of the volunteer males. Results:, There was a pattern of increased demethylation with alcohol consumption at the 2 imprinted loci with a significant difference observed at the IG-DMR between the nondrinking and heavy alcohol consuming groups. Greater inter-individual variation in average methylation was observed at the H19 DMR and individual clones were more extensively demethylated than those of the IG-DMR. CpG site #4 in the IG-DMR was preferentially demethylated among all individuals and along with the H19 DMR CpG site #7 located within the CTCF binding site 6 showed significant demethylation in the alcohol consuming groups compared with the control group. Conclusion:, This study demonstrates a correlation between chronic alcohol use and demethylation of normally hypermethylated imprinted regions in sperm DNA. We hypothesize that, should these epigenetic changes in imprinted genes be transmitted through fertilization, they would alter the critical gene expression dosages required for normal prenatal development resulting in offspring with features of FASD. [source] Relationship between seminal ascorbic acid and sperm DNA integrity in infertile menINTERNATIONAL JOURNAL OF ANDROLOGY, Issue 6 2006Gyun Jee Song Summary Ascorbic acid has recently been reported to protect sperm DNA from the damage induced by exogenous oxidative stress in vitro. But, there is no report on seminal ascorbic acid and sperm DNA fragmentation in infertile men. In this study, we asked whether sperm DNA damage correlates with seminal ascorbic acid levels. Sperm DNA fragmentation index (DFI) was analysed in 75 men by flow cytometry after acridine orange staining. We also measured the levels of seminal plasma ascorbic acid and total antioxidant capacity. Abnormal sperm DNA integrity (DFI , 30%) was observed in 12% of the patients with normal semen parameters and in 52% of the patients with abnormal semen parameters. There were significant correlations between the level of DFI and conventional semen parameters including sperm count, motility and morphology (r = ,0.29, ,0.55 and ,0.53 respectively; p < 0.05). Seminal ascorbic acid level was significantly lower in the patients with leucospermia than the patient with normal semen parameters. Interestingly, a significantly greater percentage of men with abnormal DFI were observed in the patients with low levels of seminal ascorbic acid compared with those with normal or high levels of ascorbic acid (59% vs. 33%, p < 0.05). Men with insufficient seminal ascorbic acid frequently have sperm DNA damage. [source] DNA methylation patterns at the IGF2-H19 locus in sperm of Swiss Landrace and Swiss Large White boarsJOURNAL OF ANIMAL BREEDING AND GENETICS, Issue 6 2009Petra Giannini Summary DNA methylation patterns at the IGF2-H19 locus were investigated in sperm DNA from Swiss Landrace (SL) and Swiss Large White (LW) boars. The putative IGF2 differentially methylated regions (DMR) 0, 1 and 2, a quantitative trait nucleotide (QTN) region in the intron 3 and a CpG island in the intron 4 of the IGF2 gene as well as three regions around porcine CTCF binding sites within the H19 differentially methylated domain (DMD) were selected for the DNA methylation analysis. In both breeds putative IGF2 DMR0, 1, 2 and H19 DMD were hypermethylated. Significant differences in DNA methylation content were found between the two breeds in the two DMD regions proximal to the H19 gene. The IGF2 QTN region and the CpG island in the IGF2 intron 4 were hypomethylated in sperm DNA of both breeds. The methylation analysis revealed significantly more methylated CpG sites in the intron 4 of sperm from the LW breed than in that from SL. No difference was found in global DNA methylation between the two breeds. These results indicate differences in DNA methylation patterns between breeds and it remains to be established whether variation in DNA methylation patterns impacts on phenotypic traits. [source] Mouse spermatozoa contain a nuclease that is activated by pretreatment with EGTA and subsequent calcium incubationJOURNAL OF CELLULAR BIOCHEMISTRY, Issue 5 2008Segal M. Boaz Abstract We demonstrated that mouse spermatozoa cleave their DNA into ,50 kb loop-sized fragments with topoisomerase IIB when treated with MnCl2 and CaCl2 in a process we term sperm chromatin fragmentation (SCF). SCF can be reversed by EDTA. A nuclease then further degrades the DNA in a process we term sperm DNA degradation (SDD). MnCl2 alone could elicit this activity, but CaCl2 had no effect. Here, we demonstrate the existence of a nuclease in the vas deferens that can be activated by ethylene glycol tetraacetic acid (EGTA) to digest the sperm DNA by SDD. Spermatozoa were extracted with salt and dithiothreitol to remove protamines and then incubated with EGTA. Next, the EGTA was removed and divalent cations were added. We found that Mn2+, Ca2+, or Zn2+ could each activate SDD in spermatozoa but Mg2+ could not. When the reaction was slowed by incubation on ice, EGTA pretreatment followed by incubation in Ca2+ elicited the reversible fragmentation of sperm DNA evident in SCF. When the reactions were then incubated at 37°C they progressed to the more complete degradation of DNA by SDD. EDTA could also be used to activate the nuclease, but required a higher concentration than EGTA. This EGTA-activatable nuclease activity was found in each fraction of the vas deferens plasma: in the spermatozoa, in the surrounding fluid, and in the insoluble components in the fluid. These results suggest that this sperm nuclease is regulated by a mechanism that is sensitive to EGTA, possibly by removing inhibition of a calcium binding protein. J. Cell. Biochem. 103: 1636,1645, 2008. © 2007 Wiley-Liss, Inc. [source] The sperm nuclear matrix is required for paternal DNA replication,JOURNAL OF CELLULAR BIOCHEMISTRY, Issue 3 2007Jeffrey A. Shaman Abstract The mammalian sperm nucleus provides an excellent model for studying the relationship between the formation of nuclear structure and the initiation of DNA replication. We previously demonstrated that mammalian sperm nuclei contain a nuclear matrix that organizes the DNA into loop domains in a manner similar to that of somatic cells. In this study, we tested the minimal components of the sperm nucleus that are necessary for the formation of the male pronucleus and for the initiation of DNA synthesis. We extracted mouse sperm nuclei with high salt and dithiothreitol to remove the protamines in order to form nuclear halos. These were then treated with either restriction endonucleases to release the DNA not directly associated with the nuclear matrix or with DNAse I to digest all the DNA. The treated sperm nuclei were injected into oocytes, and the paternal pronuclear formation and DNA synthesis was monitored. We found that restriction digested sperm nuclear halos were capable of forming paternal pronuclei and initiating DNA synthesis. However, when isolated mouse sperm DNA or sperm DNA reconstituted with the nuclear matrices were injected into oocytes, no paternal pronuclear formation or DNA synthesis was observed. These data suggest that the in situ nuclear matrix attachment organization of sperm DNA is required for mouse paternal pronuclear DNA synthesis. J. Cell. Biochem. 102: 680,688, 2007. © 2007 Wiley-Liss, Inc. [source] Effect of Alcohol Consumption on CpG Methylation in the Differentially Methylated Regions of H19 and IG-DMR in Male Gametes,Implications for Fetal Alcohol Spectrum DisordersALCOHOLISM, Issue 9 2009Lillian A. Ouko Background:, Exposure to alcohol in utero is the main attributable cause of fetal alcohol spectrum disorders (FASD) which in its most severe form is characterized by irreversible behavioral and cognitive disability. Paternal preconception drinking is not considered to be a significant risk factor, even though animal studies have demonstrated that chronic paternal alcohol consumption has a detrimental effect on the physical and mental development of offspring even in the absence of in utero alcohol exposure. It has been documented that alcohol can reduce the levels and activity of DNA methyltransferases resulting in DNA hypomethylation and that reduced methyltransferase activity can cause activation of normally silenced genes. The aim of this study was to establish a link between alcohol use in men and hypomethylation of paternally imprinted loci in sperm DNA in genomic regions critical for embryonic development, thus providing a mechanism for paternal effects in the aetiology of FASD. Methods:, Sperm DNA from male volunteers was bisulfite treated and the methylation patterns of 2 differentially methylated regions (DMRs), H19 and IG-DMR, analyzed following sequencing of individual clones. The methylation patterns were correlated with the alcohol consumption levels of the volunteer males. Results:, There was a pattern of increased demethylation with alcohol consumption at the 2 imprinted loci with a significant difference observed at the IG-DMR between the nondrinking and heavy alcohol consuming groups. Greater inter-individual variation in average methylation was observed at the H19 DMR and individual clones were more extensively demethylated than those of the IG-DMR. CpG site #4 in the IG-DMR was preferentially demethylated among all individuals and along with the H19 DMR CpG site #7 located within the CTCF binding site 6 showed significant demethylation in the alcohol consuming groups compared with the control group. Conclusion:, This study demonstrates a correlation between chronic alcohol use and demethylation of normally hypermethylated imprinted regions in sperm DNA. We hypothesize that, should these epigenetic changes in imprinted genes be transmitted through fertilization, they would alter the critical gene expression dosages required for normal prenatal development resulting in offspring with features of FASD. [source] Determination of nucleic acid by [tetra-(3-methoxy-4-hydroxyphenyl)],Tb3+ porphyrin as the fluorescence spectral probe in bis(2-ethylhexyl)sulfosuccinate sodium salt micelle systemLUMINESCENCE: THE JOURNAL OF BIOLOGICAL AND CHEMICAL LUMINESCENCE, Issue 4 2009Xin Chen Abstract A new system for the determination of nucleic acid by rare earth metallic porphyrin of [tetra-(3-methoxy-4-hydroxyphenyl)],Tb3+ [T(3-MO-4HP),Tb3+] porphyrin as fluorescence spectral probe has been developed in this paper. Nucleic acid can enhance the fluorescence intensity of the T(3-MO-4HP),Tb3+ porphyrin in the presence of bis(2-ethylhexyl)sulfosuccinate sodium salt(AOT) micelle. In pH 8.00 Tris,HCl buffer solution, under optimum conditions, the enhanced fluorescence intensity is in proportion to the concentration of nucleic acids in the range of 0.05,3.00 µg mL,1 for calf thymus DNA (ct DNA) and 0.03,4.80 µg mL,1 for fish sperm DNA(fs DNA). Their detection limits are 0.03 and 0.01 µg mL,1, respectively. In addition, the binding interaction mechanism between T(3-MO-4HP),Tb3+ porphyrin and ct DNA is also investigated by resonance scattering and fluorescence spectra. The maximum binding number is calculated by molar ratio method. The new system can be used for the determination of nucleic acid in pig liver, yielding satisfactory results. Copyright © 2009 John Wiley & Sons, Ltd. [source] No evidence for germ-line transmission following prenatal and early postnatal AAV-mediated gene deliveryTHE JOURNAL OF GENE MEDICINE, Issue 5 2005Marcus Jakob Abstract Background Recombinant adeno-associated viruses have been used successfully in a number of pre-clinical and clinical gene therapy studies. Since there is a broad consensus that gene therapy must not lead to germ-line transmission, the potential of such vectors for inadvertent gene transfer into germ cells deserves special attention. This applies in particular to pre- or perinatal vector application which has been considered for diseases presenting with morbidity already at birth. Methods AAV serotype 2 derived vectors carrying a ,-galactosidase reporter gene or human clotting factor IX cDNA were injected intraperitoneally or via a yolk sac vein into mouse fetuses or administered intravascularly to newborn mice. Tissue samples of the treated animals including the gonads as well as sperm DNA, obtained by differential lysis of one testis of each male animal, and the offspring of all treated mice were investigated for the presence of vector DNA by nested PCR. In positive samples, the copy number of the vector was determined by quantitative real-time PCR. Results AAV vectors administered intraperitoneally or intravascularly to fetal or newborn mice reached the gonads of these animals and persisted there for time periods greater than one year. Intravascular injection of the vector resulted more frequently in gene transfer to the gonads than intraperitoneal injection. Vector copy numbers in the gonads ranged from 0.3 to 74 per 104 cell equivalents. However, neither in isolated sperm DNA from the treated animals nor in their offspring were vector sequences detectable. Conclusions These data suggest the risk of inadvertent germ-line transmission following prenatal or early postnatal AAV type 2 mediated gene delivery to be very low. Copyright © 2005 John Wiley & Sons, Ltd. [source] Leucocytes and intrinsic ROS production may be factors compromising sperm chromatin condensation statusANDROLOGIA, Issue 2 2010R. Henkel Summary Considering that the final protection of the DNA against major assaults in terms of chromatin condensation is finalised in the epididymis, it is not known how sperm production of reactive oxygen species (ROS) and inflammatory processes can contribute to protamine deficiency that is predetermined in the testes. Therefore, this study aimed at investigating relationships between poor chromatin condensation, morphology, ROS production, DNA damage and the impact of the presence of leucocytes. In 70 patients, sperm DNA status was determined using TUNEL and chromomycin A3 (CMA3) assays, and ROS-production by means of dihydroethidine. Morphology was evaluated according to strict criteria. The percentage of CMA3 -positive spermatozoa and leucocyte concentration (r = 0.178, P = 0.0377) as well as percentage of ROS-positive spermatozoa (r = 0.3010; P = 0.012) correlated significantly. Particularly, patients with leucocyte counts >0.5 × 106 ml,1 exhibited higher CMA3 positivity. No association was found between CMA3 positivity, TUNEL positivity and sperm morphology. While P- (poor prognosis: 0,4% normal morphology) and G-pattern (good prognosis: 5,14% normal morphology) morphology did not differ regarding chromatin condensation, P-pattern patients had a significantly higher percentage of DNA fragmentation (P = 0.0323). As oxidative stress is associated with disturbed chromatin condensation, results suggest that the idea that under-protamination of sperm DNA will automatically lead to DNA fragmentation might have to be revisited. [source] Evaluation of aneuploidy and DNA damage in human spermatozoa: applications in field studiesANDROLOGIA, Issue 4-5 2000S. D. Perreault With the goal of incorporating measures of sperm nuclear integrity in an epidemiology study, semen samples from young Czech men were analysed for sperm aneuploidy and sperm chromatin structure in addition to routine measures of sperm production and quality. The exposure in question was to high seasonal air pollution containing reactive polyaromatic hydrocarbons potentially capable of affecting spermatogenesis and damaging sperm DNA. The sperm aneuploidy assay uses fluorescence in situ hybridization to label selected sperm chromosomes; as applied in this study, the sex chromosomes (X,Y) and chromosome 8 were targeted. The sperm chromatin structure assay detects sperm nuclei with increased susceptibility to denaturation, a feature that is associated with DNA damage. Logistically, these assays were relatively easy to incorporate into the study design. The aneuploidy assay provided information suggesting that exposure to high levels of air pollution may increase the risk of sperm aneuploidy and that it is important to control for exposure to cigarette smoke and/or alcohol in such studies. The sperm chromatin structure assay provided valuable baseline information about Czech semen donors and data suggestive of an adverse effect of smoking and air pollution on spermatozoa that merits further investigation. [source] Synthesis, characterization and biological studies of alkenyl-substituted titanocene(IV) carboxylate complexesAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 9 2010Goran N. Kalu, erovi Abstract The carboxylate compounds [Ti(,5 -C5H5)(,5 -C5H4{CMe2(CH2CH2CHCH2)})(O2CCH2SXyl)2] (2; Xyl = 3,5-Me2C6H3) and [Ti(,5 -C5H5)(,5 -C5H4{CMe2(CH2CH2CHCH2)})(O2CCH2SMesl)2] (3; Mes 1 = 2,4,6-Me3C6H2) were synthesized by the reaction of [Ti(,5 -C5H5)(,5 -C5H4{CMe2(CH2CH2CHCH2)})Cl2] (1) with 2 equivalents of xylylthioacetic acid or mesitylthioacetic acid, respectively. Compounds 2 and 3 were characterized by spectroscopic methods. The cytotoxic activity of 1,3 was tested against human tumor cell lines from four different histogenic origins,8505C (anaplastic thyroid cancer), DLD-1 (colon cancer) and the cisplatin sensitive A253 (head and neck cancer) and A549 (lung carcinoma),and compared with those of the reference complex [Ti(,5 -C5H5)2Cl2] (R1) and cisplatin. Surprisingly, the cytotoxic activities of the carboxylate derivatives were lower than those of their corresponding dichloride analogue (1). However, complexes 1,3 were more active than titanocene dichloride against all the studied cells with the exception of complex 2 against A253 and A549 cell lines. DNA-interaction tests were also carried out. Solutions of all the studied complexes were treated with different concentrations of fish sperm DNA, observing modifications of the UV spectra with intrinsic binding constants of 2.99 × 105, 2.45 × 105, and 2.35 × 105M,1 for 1,3. Structural studies based on density functional theory calculations of 2 and 3 were also carried out. Copyright © 2010 John Wiley & Sons, Ltd. [source] Impact of the Aliphatic Dicarboxylate Chain of Novel Dinuclear Palladium(II) Complexes: Synthesis and Biological EvaluationCHINESE JOURNAL OF CHEMISTRY, Issue 2 2010Enjun Gao Abstract Five dinuclear palladium(II) complexes with HOOC(CH2)nCOOH (n=2,6) and 2,2,-bipyridine ligands were synthesigned by a reaction with K2PdCl4. To prepare such complexes with different aliphatic dicarboxylate chain lengths was in an attempt to correlate this length factor, which influences the biological activity of the complexes, with fluorescence spectra, DNA cleavage and cytotoxic activity. The results indicate that the complexes bind to fish sperm DNA (FS-DNA) in an intercalative mode via fluorescence spectra, and the five complexes show different cleavage of supercoiled DNA, and then a cytotoxicity assay of these dinuclear palladium(II) complexes on human tumor cell lines was performed. In most of the cell lines, complex 5 (n=6) and 4 (n=5) showed much higher cytotoxicity than cis -platin. On the other hand, complex 3 (n=4) was found to be moderately active, and complex 1 (n=2), complex 2 (n=3) were found only marginally cytotoxic. Implications of these findings were discussed from a structure-activity relationship. [source] Structure, DNA Binding Studies and Cytotoxicity of Complex [Pd(phen)(L -asp)]·3H2OCHINESE JOURNAL OF CHEMISTRY, Issue 6 2009Enjun GAO Abstract The palladium(II) complex of [Pd(phen)(L -asp)]·3H2O (phen=1,10-phenanthroline, H2L-asp=L -aspartic acid) has been synthesized from a solution reaction and analyzed by elemental analyses, 1H NMR and IR spectra. Moreover, the complex has been structurally characterized by single-crystal X-ray diffractometry. The cytotoxicity assay of the complex and cis -DDP as reference substance against three different cancer cell lines (Hela, Hep-G2 and KB) has been conducted. The results show that the Pd complex exhibits higher cytotoxicity against Hela system. The study on the interaction of the Pd complex with fish sperm DNA (FS-DNA) has been performed with diverse spectroscopic techniques, showing that the complex is bound to the fish sperm DNA via an intercalative mode. Gel electrophoresis assay demonstrates the ability of the complex to cleave the pBR 322 plasmid DNA. [source] Resonance Light Scattering Imaging Detection of Single Suprahelical Species of DNA Induced by Porphine-5,10,15,20-tetrakis(p -phenyltrimethylaminium)CHINESE JOURNAL OF CHEMISTRY, Issue 1 2006Xi-Dong Liu Abstract A resonance light scattering (RLS) imaging method was proposed based on imaging and measuring the RLS features of single suprahelical species of DNA, and its application to DNA assay was also investigated. In acidic medium, porphine-5,10,15,20-tetrakis(p -phenyltrimethylaminium) (PTPTMA), could stack along the molecular surface of DNA with the mode of long-range assembly to induce the formation of suprahelical species of DNA, resulting in strong RLS signals in the range of 450,510 nm. Under the excitation of 488 nm light beam of argon ion laser source, single suprahelical species could be observed with the aid of a common microscope due to the strong scattered light emitted by the suprahelical species. By capturing the RLS images of the single suprahelical species with a cooled charge coupled device (CCD) camera, and analyzing the RLS data, herein an RLS imaging method of DNA was proposed based on the linear relationship between the counts of suprahelical species in the detection focus plane and the concentration of DNA in nanograms. When 1.8??µmol/L PTPTMA was employed, both calf thymus DNA (ct DNA) and fish sperm DNA (fs DNA) in the range of 25,1100 ng/mL could be detected with the limits of detection lower than 25 ng/mL (3,). Four synthetic samples were detected satisfactorily with relative standard deviations less than 5.1%. [source] | ||||||||||||||||