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Nickel is associated with reproductive toxicity, but little is known about the molecular mechanisms of nickel-induced effects on sperm chromatin and protamine-like proteins (PLs). In the present work, we analyzed PLs from Mytilus galloprovincialis by urea-acetic acid polyacrylamide gel electrophoresis (AU-PAGE) and SDS-PAGE and assessed their binding to DNA by Electrophoretic Mobility Shift Assay (EMSA) after exposing mussels to 5, 15, and 35 µM NiCl2 for 24 h. In addition, a time course of digestion with MNase and release of PLs from sperm nuclei by the NaCl gradient was performed. For all exposure doses, in AU-PAGE, there was an additional migrating band between PL-III and PL-IV, corresponding to a fraction of PLs in the form of peptides detected by SDS-PAGE. Alterations in DNA binding of PLs were observed by EMSA after exposure to 5 and 15 µM NiCl2, while, at all NiCl2 doses, increased accessibility of MNase to sperm chromatin was found. The latter was particularly relevant at 15 µM NiCl2, a dose at which increased release of PLII and PLIII from sperm nuclei and the highest value of nickel accumulated in the gonads were also found. Finally, at all exposure doses, there was also an increase in PARP expression, but especially at 5 µM NiCl2. A possible molecular mechanism for the toxic reproductive effects of nickel in Mytilus galloprovincialis is discussed.

The objective of this research was to evaluate the effect of sperm on chromatin stability and its relationship with the membrane integrity structural – physiological and the rate of fertilization of female sheep. Ejaculates of sperm (2 × 10 9 sperm·mL -1 ) with 70% of motility were collected using an artificial vagina (n=5, 2 years old. For this, each ram was served with fifteen female sheep (n=75), generating thus five different Groups (A, B, C, D, and E). A control Group also was considered. Sperm nuclear chromatin stability (NCS) was evaluated using the Borate Buffer (BB), Sodium Dodecyl Sulfate (SDS), and the mixture of Ethylenediaminetetraacetic acid (EDTA) + SDS. The fertilization rate was evaluated after 16-18 hours post sperm injection. Sperm concentration showed a significant difference (P0.05). A high correlation (r 2 =0.52) was observed between morphology and motility, and the fertilization rate was 74.6% (n=56). It was concluded in general that techniques to evaluate nuclear condensation values do have a high likelihood to give a diagnosis about the future potential of sperm populations in Junín ram. El objetivo de esta investigación fue evaluar el efecto de los espermatozoides sobre la estabilidad de la cromatina y su relación con la integridad de la membrana estructural – fisiológica y la tasa de fertilización de las ovejas hembras. Las eyaculaciones de espermatozoides (2 × 10 9 espermatozoides·ml -1 ) con un 70 % de motilidad se recogieron mediante una vagina artificial (n=5, 2 años). Para ello, cada carnero se servía con quince ovejas hembra (n=75), generando así cinco grupos diferentes (A, B, C, D y E). También se consideró un grupo de control. La estabilidad de la cromatina nuclear (NCS) de los espermatozoides se evaluó utilizando el tampón de borato (BB), el dodecil sulfato de sodio (SDS) y la mezcla de ácido etilendiaminotetraacético (EDTA) + SDS. La tasa de fertilización se evaluó después de 16-18 horas después de la inyección de espermatozoides. La concentración de espermatozoides mostró diferencias significativas (P0,05). Se observó una alta correlación (r 2 =0,52) entre morfología y motilidad, y la tasa de fecundación fue del 74,6% (n=56). Se concluyó en general que las técnicas para evaluar los valores de condensación nuclear tienen una alta probabilidad de dar un diagnóstico sobre el potencial futuro de las poblaciones de espermatozoides en carneros de Junín. ide_85@hotmail.com

Male germ cells experience a drastic chromatin remodeling through the nucleo-histone to nucleo-protamine (NH-NP) transition necessary for proper sperm functionality. Post-translational modifications (PTMs) of H4 Lys5, such as acetylation (H4K5ac), play a crucial role in epigenetic control of nucleosome disassembly facilitating protamine incorporation into paternal DNA. It has been shown that butyrylation on the same residue (H4K5bu) participates in temporal regulation of NH-NP transition in mice, delaying the bromodomain testis specific protein (BRDT)-dependent nucleosome disassembly and potentially marking retained nucleosomes. However, no information was available so far on this modification in human sperm. Here, we report a dual behavior of H4K5bu and H4K5ac in human normal spermatogenesis, suggesting a specific role of H4K5bu during spermatid elongation, coexisting with H4K5ac although with different starting points. This pattern is stable under different testicular pathologies, suggesting a highly conserved function of these modifications. Despite a drastic decrease of both PTMs in condensed spermatids, they are retained in ejaculated sperm, with 30% of non-colocalizing nucleosome clusters, which could reflect differential paternal genome retention. Whereas no apparent effect of these PTMs was observed associated with sperm quality, their presence in mature sperm could entail a potential role in the zygote.

Background: Formalin is commonly applied as an antiseptic and tissue fixative. It has reactive molecules that lead to its cytotoxic effects. According to recent studies, formalin causes a change in the testicular and sperm structure and L-carnitine (LC) acts as an antioxidant to counteract its effects. Objectives: This study aimed to investigate the protective effects of LC on the parameters, chromatin condensation and apoptosis of mice sperm exposed to formalin. Materials and Methods: In this experimental study, 24 balb/c mice (25-40 gr ,10-12 wk) were divided into three groups (n = 8/each): group I without any injections or gavage; group II, received 10 mg/ kg formalin intraperitoneally (I.P); and group III was exposed to formalin and LC, where a dose of 10 mg/kg formalin was injected I.P daily and LC the dose of 100 mg/kg was kept in a solvent solution. After 31 days, the sperm examination was performed as follows: to evaluate chromatin and DNA quality of the sperm, we applied aniline blue (AB), toluidine blue (TB), chromomycin A3 (CMA3), and terminal transferase-mediated deoxy uridine triphosphate biotin end labeling (TUNEL) tests. Results: Sperm parameters such as count, motility, morphology, and viability displayed a significant decrease in the formalin group. While the data exhibited a considerable augment in sperm parameters in the formalin + LC than the formalin and control groups (p < 0.001), significant differences were detected between groups with respect to TB staining, TUNEL test, CMA3 test and AB staining in the formalin and formalin + LC groups. Conclusion: LC can reduce the negative effects of formalin on sperm parameters, chromatin stability, and percentage of apoptosis in an animal model. Key words: Formalin, L-carnitine, Mice, Sperm chromatin, Apoptosis.

Chromium (VI) is the most dangerous oxidation state among the stable forms of chromium. In this work, we evaluated the effect of exposing Mytilus galloprovincialis for 24 h to 1, 10, and 100 nM chromium (VI) on the properties of Protamine-like (PLs) and their gene levels in the gonads. Specifically, we analyzed, by AU-PAGE and SDS-PAGE, PLs extracted from unexposed and exposed mussels. In addition, via EMSA, we evaluated the ability of PLs to bind DNA and also verified their potential to protect DNA from oxidative damage. Finally, we assessed possible alterations in gonadal expression of mt10, hsp70, and genes encoding for PLs-II/PL-IV and PL-III. We found that for all experimental approaches the most relevant alterations occurred after exposure to 1 nM Cr(VI). In particular, a comigration of PL-II with PL-III was observed by SDS-PAGE; and a reduced ability of PLs to bind and protect DNA from oxidative damage was recorded. This dose of chromium (VI) exposure was also the one that produced the greatest alterations in the expression of both mt10 and PL-II/PL-IV encoding genes. All of these changes suggest that this dose of chromium (VI) exposure could affect the reproductive health of Mytilus galloprovincialis.

Epigenetic modifications play a special role in the male infertility aetiology. Published data indicate the link between sperm quality and sperm chromatin protamination. This study aimed to determine the relationship between methylation (5mC) and hydroxymethylation (5hmC) in sperm DNA, with respect to sperm chromatin protamination in three subpopulations of fertile normozoospermic controls and infertile patients with oligo-/oligoasthenozoospermia. For the first time, a sequential staining protocol was applied, which allowed researchers to analyse 5mC/5hmC levels by immunofluorescence staining, with a previously determined chromatin protamination status (aniline blue staining), using the same spermatozoa. TUNEL assay determined the sperm DNA fragmentation level. The 5mC/5hmC levels were diversified with respect to chromatin protamination status in both studied groups of males, with the highest values observed in protaminated spermatozoa. The linkage between chromatin protamination and 5mC/5hmC levels in control males disappeared in patients with deteriorated semen parameters. A relationship between 5mC/5hmC and sperm motility/morphology was identified in the patient group. Measuring the 5mC/5hmC status of sperm DNA according to sperm chromatin integrity provides evidence of correct spermatogenesis, and its disruption may represent a prognostic marker for reproductive failure.

Assisted reproductive technologies involving the use of spermatozoa and eggs for in vitro fertilization (IVF) have come as the solution for many infertile couples to become parents. However, in some cases, the use of ejaculated spermatozoa delivers poor IVF performance. Some studies have suggested the use of testicular spermatozoa in severe male infertility cases, but no guidelines regarding their utilization are currently available. In the present study, we found the mRNA protamine 1/protamine 2 (P1/P2) ratio to be a valuable biomarker of poor sperm function that could be used as a diagnostic key for the identification of cases that would benefit from the use of testicular spermatozoa. A total of 23 couples undergoing egg donation cycles with at least one previous cycle failure were studied. All couples underwent two consecutive intracytoplasmic sperm injection (ICSI) cycles with either ejaculated or testicular spermatozoa (TESA). The sperm mRNA P1/P2 ratio, fertilization rate, blastocyst rate, and pregnancy and live birth rate were compared. Results showed improved ICSI and clinical outcomes in cycles with testicular spermatozoa in men with altered mRNA P1/P2 ratios. TESA cycles presented significantly higher rates of fertilization (mean ± standard deviation: 76.1% ± 15.1% vs 65.5% ± 18.8%), blastocyst formation (55.0% ± 20.3% vs 30.8% ± 23.8%), and good morphological quality blastocyst (28.9% ± 22.9% vs 13.5% ± 17.9%) and also improvements on pregnancy (60.9% vs 0%) and healthy birth rates (56.5% vs 0%) than EJACULATE cycles. The results described here suggest that in patients with previous IVF/ICSI failures and aberrant mRNA protamine ratios, the use of testicular spermatozoa may be a good alternative to improve clinical outcomes.

CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior As alterações de cromatina, apesar de não serem avaliadas no espermograma de rotina, sabidamente influenciam a fertilidade de touros. O método de avaliação cromatínica mais utilizado é o SCSA (Sperm Chromatin Structure Assay), entretanto este é de alto custo. Como alternativa a esta metodologia, a coloração com azul de toluidina (AT) após hidrólise ácida associada a análises computacionais se apresenta como uma ferramenta equivalente e acessível. Além de apresentar menor custo, esta metodologia mensura a intensidade de descompactação e heterogeneidade da cromatina. No entanto, ainda não se definiu que níveis de descompactação e heterogeneidade interferem na fertilidade do touro. Este trabalho tem como objetivos definir os níveis de descompactação e heterogeneidade cromatínicas aceitáveis para que não prejudique a fertilidade do touro e o desenvolvimento embrionário, propor uma classificação das alterações cromatínicas de espermatozoides bovinos de acordo com sua localização e verificar se cada tipo de alteração influencia no processo de fecundação e de desenvolvimento embrionário inicial. Para tal, foram utilizadas amostras de sêmen de animais induzidos à subfertilidade, as quais foram utilizadas para produção in vitro de embriões (PIVE). Estas amostras foram avaliadas pelo método de coloração com AT e posterior análise computacional. Para caracterização da fertilidade das amostras de sêmen, foram avaliadas as taxas de clivagem no segundo dia e de blastocistos morfologicamente normais no sétimo dia de cada rotina de PIVE. Utilizando análise de imagem computacional, foi possível fazer a seguinte classificação das alterações cromatínicas: descompactação na base da cabeça (DB), na metade basal (DMB), em áreas dispersas (AD), no eixo central da cabeça (DEC) e em toda a extensão da cabeça (DT). Foi utilizado teste de correlação de Pearson (pp>0,05) para correlacionar essas alterações com a eficiência da PIVE. Em relação à clivagem, DEC e DT apresentaram correlações negativas e significativas (p=0,03 e p=0,047, respectivamente), DB e DMB apresentaram uma tendência para uma correlação negativa (p=0,06 e p=0,07, respectivamente). Em relação à formação de blastocisto, DB apresentou uma tendência para correlação negativa (p=0,09). Além disso, foi testado dois níveis de anormalidade em relação à heterogeneidade (Het) e descompactação (Des) da cromatina: acima de 5% e acima de 10%. A Des apresentou correlação significativa em relação à clivagem quando utilizado níveis acima de 5 e 10% de descompactação (p=0,03 e p=0,02, respectivamente). Já para Het, não houve correlações significativas tampouco tendências com a eficiência da PIVE. Assim, ficou demonstrado que em PIVE, a descompactação no eixo central e total da cabeça do espermatozoide interfere intensamente no processo de fecundação. Os demais tipos de alterações também podem interferir na fecundação de forma menos intensa. A DB pode interferir na formação de blastocistos. Para a avaliação da descompactação, espermatozoides acima de 5% de Des interferem no processo de fecundação. Já a heterogeneidade, independentemente do nível considerado, não interfere em ambos os parâmetros avaliados. Chromatin alterations, despite not being evaluated in the spermogram routine affect the fertility of bulls. The most used method of chromatin evaluation is the SCSA (Sperm Chromatin Structure Assay). However it is a high method cost. An alternative method is the toluidine blue (TB) after acid hydrolysis associated with computer analysis - this method is presented as an equivalent and affordable tool. In addition to its lower cost, this methodology measures the intensity of decondensation and heterogeneity chromatin. However, it has not yet determined which decondensation and heterogeneity levels interfere with bull fertility. This study aims to define which levels of decondensation and heterogeneity chromatin are acceptable in order not to prejudice the bull fertility and the embryonic development. It also aims to propose a classification of cattle sperm chromatin alteration according to their location, and it also aims to verify if each type of alteration influences the process of fertilization and the early embryonic development. To this, animals semen samples induced to subfertile were used for in vitro production of embryos (IVP). These samples were evaluated using the AT method, and computer analysis. To characterize the semen fertility samples, cleavage ratio were evaluated on the second day and morphologically normal blastocysts in the seventh day of each IVF. With the use of computer image analysis it was possible to make the following classification of chromatin alterations: decondensation of the base of the head (DB), in the basal half (DBH), in scattered areas (SA), in the central axis of the head (DCA) and the entire length of the head (DT). It was used the estimation of Pearson (pp>0,05) in order to relate these alterations with IVP efficiency. In relation to cleavage, DCA and DT had a significant negative correlation (p=0,03 and p=0,047, respectively). DB and DBH showed a tendency to a negative correlation (p=0,06 and p=0,07, respectively). In relation to the blastocyst formation, DB showed a tendency to a negative correlation (p=0,09). In addition to this, two abnormality levels were tested in relation to the Heterogeneity (Het) and Decondensation (Des) of chromatin: above 5%, and above 10%. Des presented a significant correlation related to cleavage when used levels above 5% and 10% of decondensation (p=0,03 and p=0,02, respectively), while Het had no significant correlations neither tendencies with the IVP. It was established that the central axis decondensation of the sperm in IVP intensely affects the fertilization process. Other types of alterations may also affects, but with less intensity. DB may affect in blastocyst formation. To evaluate the decondensation, sperm above 5% Des affect the fertilization process. Related to heterogeneity, regardless of the level considered, does not interfere in both parameters evaluated. Dissertação (Mestrado)

Mercury (Hg) is an environmental pollutant that impacts human and ecosystem health. In our previous works, we reported alterations in the properties of Mytilus galloprovincialis protamine-like (PL) proteins after 24 h of exposure to subtoxic doses of toxic metals such as copper and cadmium. The present work aims to assess the effects of 24 h of exposure to 1, 10, and 100 pM HgCl2 on spermatozoa and PL proteins of Mytilus galloprovincialis. Inductively coupled plasma–mass spectrometry indicated accumulation of this metal in the gonads of exposed mussels. Further, RT-qPCR analyses showed altered expression levels of spermatozoa mt10 and hsp70 genes. In Mytilus galloprovincialis, PL proteins represent the major basic component of sperm chromatin. These proteins, following exposure of mussels to HgCl2, appeared, by SDS-PAGE, partly as aggregates and showed a decreased DNA-binding capacity that rendered them unable to prevent DNA damage, in the presence of CuCl2 and H2O2. These results demonstrate that even these doses of HgCl2 exposure could affect the properties of PL proteins and result in adverse effects on the reproductive system of this organism. These analyses could be useful in developing rapid and efficient chromatin-based genotoxicity assays for pollution biomonitoring programs.

Mercury (Hg) is an environmental pollutant that impacts human and ecosystem health. In our previous works, we reported alterations in the properties of Mytilus galloprovincialis protamine-like (PL) proteins after 24 h of exposure to subtoxic doses of toxic metals such as copper and cadmium. The present work aims to assess the effects of 24 h of exposure to 1, 10, and 100 pM HgCl2 on spermatozoa and PL proteins of Mytilus galloprovincialis. Inductively coupled plasma–mass spectrometry indicated accumulation of this metal in the gonads of exposed mussels. Further, RT-qPCR analyses showed altered expression levels of spermatozoa mt10 and hsp70 genes. In Mytilus galloprovincialis, PL proteins represent the major basic component of sperm chromatin. These proteins, following exposure of mussels to HgCl2, appeared, by SDS-PAGE, partly as aggregates and showed a decreased DNA-binding capacity that rendered them unable to prevent DNA damage, in the presence of CuCl2 and H2O2. These results demonstrate that even these doses of HgCl2 exposure could affect the properties of PL proteins and result in adverse effects on the reproductive system of this organism. These analyses could be useful in developing rapid and efficient chromatin-based genotoxicity assays for pollution biomonitoring programs.

CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico FAPEMIG - Fundação de Amparo a Pesquisa do Estado de Minas Gerais Diversos estudos têm demonstrado que durante a passagem do espermatozoide através do epidídimo a cromatina espermática sofre a formação de pontes de dissulfureto entre as protaminas, aumentando a compactação do material genético, etapa fundamental para a proteção e manutenção da estabilidade do DNA. O presente estudo tem por objetivo avaliar o processo de compactação da cromatina espermática durante a maturação do espermatozoide no epidídimo de camundongos. Para isso foram colhidos espermatozoides das regiões da cabeça, corpo e cauda do epidídimo de seis camundongos. Os espermatozoides foram avaliados por análise de imagem computacional de esfregaços corados com azul de toluidina, sendo analisada a distribuição espacial do processo de compactação da cromatina e a descompactação e heterogeneidade cromatínicas médias das cabeças dos espermatozoides. Os espermatozoides também foram avaliados por microscopia eletrônica de transmissão (MET), sendo definidos quatro níveis de baixa compactação cromatínica. A proporção de espermatozoides com alta compactação cromatínica (maduros) foi menor na cabeça quando comparada as demais regiões epididimárias, em ambas as metodologias utilizadas. Além disso, os níveis de baixa compactação na metade basal (BMB) e baixa compactação total (BCT) foram prevalentes nesta região. No corpo, houve o predomínio da baixa compactação na base (BB) e na região central (BRC). Na cauda, todos os níveis de baixa compactação diminuíram consideravelmente, sendo praticamente inexistentes, exceto na região central (BRC), que ainda prevaleceu em pequena quantidade. Baseado nesses dados foi proposta uma sequência do processo de compactação cromatínica no espermatozoide murino. A compactação teria início na extremidade apical em direção a base e das laterais para o centro da cabeça do espermatozoide, compactando-se até próximo da base. Posteriormente, a compactação se daria no sentido da inserção da cauda (base) para o centro e por fim, na região central da cabeça. A análise da descompactação e heterogeneidade médias da cromatina feitas por análise de imagem de esfregaços corados com AT e a realizada por MET demonstraram que o processo de compactação cromatínica do espermatozoide de camundongos iniciado durante a espermiogênese, continua durante o trânsito pelo epidídimo. Several studies have shown that during the passage of the spermatozoid through the epididymis, the spermatic chromatin undergoes the formation of disulfide bridges between the protamines increasing the condensation of the genetic material, a fundamental step for the protection and maintenance of DNA stability. The present study aims to evaluate the process of sperm condensation of chromatin during spermatozoid maturation in the epididymis of mice. For this, spermatozoa were collected from the head, body and tail regions of the epididymis of six mice. These spermatozoa were evaluated by computational image analysis of smears stained with toluidine blue, analyzing the spatial distribution of the condensation of chromatin process and, the mean decondensation and heterogeneity of the sperm heads. Spermatozoa were also evaluated by transmission electron microscopy (TEM), and four levels of non-condensation were defined. The proportion of spermatozoa with high chromatin (mature) condensation was lower in the head when compared to the other epididymal regions, in both methodologies used. In addition, low condensation levels in the basal half (LBH) and the entire length of the head (LCT) were prevalent in this region. In the body, there was a predominance of low condensation of the base (LB) and in the central region (LCR). In the tail, all levels of low condensation decreased considerably, being practically non-existent, except in the central region (LCR), which still were prevailed in small numbers. Based on these data, a sequence of the condensation process in the murine spermatozoa was proposed. The condensation would start at the apical region towards the base and from the lateral sides to the center of the spermatozoa's head, and compaction process would finish near the base. Subsequently, the compaction would occur in the direction of the insertion of the tail (base) to the center and finally, in the central region of the head. The analysis of the means of decondensation and heterogeneity of the chromatin made by image analysis of TB stained smears and the ones which were performed by TEM demonstrated that the process of chromatin compression of mice spermatozoa started during spermiogenesis continues during transit in the epididymis. Dissertação (Mestrado)

Background Spermatogenesis is the process by which germ cells develop into spermatozoa in the testis. Sperm protamines are small, arginine-rich nuclear proteins which replace somatic histones during spermatogenesis, allowing a hypercondensed DNA state that leads to a smaller nucleus and facilitating sperm head formation. In eutherian mammals, the protamine-DNA complex is achieved through a combination of intra- and intermolecular cysteine cross-linking and possibly histidine-cysteine zinc ion binding. Most metatherian sperm protamines lack cysteine but perform the same function. This lack of dicysteine cross-linking has made the mechanism behind metatherian protamines folding unclear. Results Protamine sequences from UniProt’s databases were pulled down and sorted into homologous groups. Multiple sequence alignments were then generated and a gap weighted relative entropy score calculated for each position. For the eutherian alignments, the cysteine containing positions were the most highly conserved. For the metatherian alignment, the tyrosine containing positions were the most highly conserved and corresponded to the cysteine positions in the eutherian alignment. Conclusions High conservation indicates likely functionally/structurally important residues at these positions in the metatherian protamines and the correspondence with cysteine positions within the eutherian alignment implies a similarity in function. One possible explanation is that the metatherian protamine structure relies upon dityrosine cross-linking between these highly conserved tyrosines. Also, the human protamine P1 sequence has a tyrosine substitution in a position expecting eutherian dicysteine cross-linking. Similarly, some members of the metatherian Planigales genus contain cysteine substitutions in positions expecting plausible metatherian dityrosine cross-linking. Rare cysteine-tyrosine cross-linking could explain both observations.

Background: Environmental stressors like radiation are a cause for male infertility. The quantum of UV-A in solar ultraviolet (UV) radiation surpasses the amount of UVB by 10 to 100 times, penetrates deeper than UV-B into tissue and mediates possible molecular damage, which warrants evaluation of the impact of UV-A on human spermatozoa. Aim: To determine the differences in effects and responses of UV-A exposure on sperm cells from fertile volunteers and infertile men. Materials and Methods: The study subjects were divided into Group I (Control) and Group II (Infertile). The impact of UV-A on sperm viability, nuclear integrity, chromatin maturity and DNA fragmentation (pre-and post-exposure) was evaluated using standard techniques. Antioxidant enzyme activity assays viz. Lipid Peroxidation (LPO), Superoxide Dismutase (SOD) and Catalase were also analysed. Statistical significance was considered at p < 0.05. Results: This study revealed significant decline in%viability in Group II after UV-A exposure when compared with pre-exposed Group I. The percent sperm with disrupted nuclear toroidal assembly significantly increased in infertile group after exposure, leaving the DNA vulnerable to damage. A significant elevation was observed in the percent immature forms correlated with the significant reduction in% halo formation (impaired nuclear chromatin decondensation) in both post-treated groups as compared to pre-treated groups, suggesting that disruption of sperm toroid triggers DNA damage. UV-A exposure resulted in increased LPO with decrease in antioxidant enzymes in these groups. The percent decline in viability, chromatin decondensation (halo) and antioxidant enzymes were higher in Group II than in Group I. In addition, the percent increase in disrupted toroids and immature chromatin in Group II suggested that the deleterious impact of UV-A on spermatozoa from the infertile group is significantly greater than that of fertile individuals. Conclusion: This study thus revealed that short term UV-A exposure adversely impacts spermatozoa of infertile males to a greater extent than that of the fertile group. Thus, specific awareness and precautions are imperative for occupationally exposed individuals.

Background: Prescribing antidepressant drugs is becoming common. These drugs are known to affect sexual functions. Objective: The study is aimed to assess the effects of amitriptyline and venlafaxine on sperm parameters and evaluate Malondialdehyde (MDA) and 1, 1-Diphenyl-2-picryl-hydrazyl values in BALB/ mice spermatozoa. Materials and Methods: Forty adult male BALB/c mice were separated into five groups. Group Ι (control) received distilled water; group ΙΙ amitriptyline (4 mg/kg); group ΙΙΙ amitriptyline (4 mg/kg) +vitamin C (10 mg/kg); group ΙV venlafaxine (2 mg/kg); and group V received vitamin C (10 mg/kg) + venlafaxine (2 mg/kg). All drugs were administered by oral gavage for 35 days. After excision of caudal epididymis, it was located in 1 mL Ham's F10 medium at 37oC for 15 min and then analysis of sperm parameters was performed. To examine lipid peroxidation and total antioxidant capacity, the MDA and 1, 1-Diphenyl-2-picryl-hydrazyl were measured, respectively. Results: The mean sperm parameters in the group treated with amitriptyline were significantly lower than in the other groups. MDA tests showed a significant difference between amitriptyline and control groups (p=0.007). Conclusion: The results of this study showed that amitriptyline consumption can weaken sperm parameters, which can be attributed to the increased production of ROS and toxicity resulting from amitriptyline consumption. Moreover, venlafaxine improved sperm parameters in mice and the lipid peroxidation in this group did not change compared to the control group.

Background: Teratoasthenozoospermia (TA) is a severe form of male infertility with no clear etiology. Objective: To compare the level of intracellular anion superoxide (O2–), heat shock protein A2 (HSPA2) and protamine deficiencies in ejaculated spermatozoa between teratoasthenozoospermic and normozoospermic men. Materials and Methods: In this case- control study, semen samples of 20 infertile men, with TA (with normal morphology lower than 4%_ and total motility lower than 40% ) as the case group and 20 normozoospermic fertile men as the control group were evaluated for intracellular O2 – and HSPA2 by flow cytometry and protamine deficiency by Chromomycin A3 (CMA3) test. Results: The rate of CMA3+ spermatozoa in the case group was higher than controls (p=0.001). The percentages of HSPA2+ spermatozoa in the cases were significantly lower than controls (p=0.001). Also, intracellular O2 – levels in the case group were significantly higher than controls (p=0.001) and had positive correlations with sperm apoptosis (r=0.79, p=0.01) and CMA3 positive sperm (r=0.76, p=0.01), but negative correlations with normal morphology (r=-0.81, p=0.01) and motility (r=-0.81, p=0.01). There was no significant correlation between intracellular O2 – and HSPA2 in the case group (r=0.041, p=0.79). Conclusion: We suggest that the increase in intracellular O2 –, decrease in spermatozoa HSPA2+, and high percentages of spermatozoa with immature chromatin might be considered as etiologies of infertility in TA patients

Background: Methamphetamine (MA) was shown to have harmful effects on male reproductive system. Objective: To investigate probable effects of daily administration of MA on sperm parameters and chromatin/DNA integrity in mouse. Material and Methods: Thirty-five NMRI male mice were divided into five groups including low, medium, and high dosage groups which were injected intraperitoneally with 4, 8 and 15 mg/kg/day for 35 days, respectively. Normal saline was injected in sham group and no medications were used in control group. Then, the mice were killed and caudal epididymis of each animal was cut and placed in Ham’s F10 medium for sperm retrieval. To evaluate sperm chromatin abnormalities, the aniline blue, toluidine blue and chromomycine A3 were used. For sperm DNA integrity and apoptosis, the acridine orange, sperm chromatin dispersion, and TUNEL assay were applied. For sperm morphology, Papanicolaou staining was done Results: Normal morphology and progressive motility of spermatozoa decreased in medium and high dosage groups in comparison with the control group (p=0.035). There was a significant increase in rate of aniline blue, toluidine blue, and chromomycine A3 positive spermatozoa in high dosage group. In a similar manner, there was an increase in rates of acridine orange, TUNEL and sperm chromatin dispersion positive sperm cells in high dosage group with respect to others. Conclusion: MA abuse in a dose-dependent manner could have detrimental effects on male reproductive indices including sperm parameters and sperm chromatin/DNA integrity in mice.

F2-isoprostanes (F2-IsoPs), stereoisomers of prostaglandin F2α generated by the free radical-induced oxidation of arachidonic acid, have been associated with different male infertility conditions. This study aimed to evaluate the role of seminal isoprostane levels and sperm characteristics in the reproductive outcome and embryo quality of 49 infertile couples. Semen analysis was performed following WHO guidelines. Sperm chromatin maturity was detected using an aniline blue (AB) assay, and DNA integrity was assessed using the acridine orange (AO) test. Seminal F2-IsoP levels were quantified by gas chromatography/negative ion chemical ionization tandem mass spectrometry (GC/NICI–MS/MS) analysis. Correlations among variables and their impact on in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) outcome were investigated. F2-IsoP levels are positively correlated with double-stranded DNA sperm (p &lt, 0.001) and negatively correlated with mature sperm chromatin (p &lt, 0.001). Patients with positive outcomes had an increased percentage of sperm with double-stranded DNA, as did patients producing high-quality embryo, who showed higher F2-IsoP levels compared to those detected in the low-quality embryo group. An intriguing relationship between a mild increase in F2-IsoP levels, DNA integrity, and embryo quality seems to indicate that the non-enzymatic oxidation of arachidonic acid can be also a marker of metabolic activity in human semen.

Objective: To evaluate the effects of low level ultraviolet (UV) radiation on sperm chromatin structure.Methods: The target study was divided into three groups: (i) males with proven fertility (n=40 ) was taken as Group I (control); (ii) Oligoasthenozoospermic (OAT) cases as Group II (n=36); (iii) males with unexplained infertility (MUI) cases (n=42) as Group III. Specific techniques were used to study the impact of UV radiation (Pre and Post UV exposure) on the sperm nuclear DNA viz. Aniline blue staining was for detection of immature chromatin. Chromomycin A3 fluorescence staining was used to determine protamine-DNA dissociation by intense fluorescence of protamine deficient sperm cells and neutral comet assay was for evaluation of DNA fragmentation. Statistical analysis was carried out using Student's t-test (GraphPad Prism Version-6). Level of significance was considered at P

Nucleoplasmin (Np) is a pentameric histone chaperone that regulates the condensation state of chromatin in different cellular processes. We focus here on the interaction of NP with the histone octamer, showing that NP could bind sequentially the histone components to assemble an octamer-like particle, and crosslinked octamers with high affinity. The three-dimensional reconstruction of the Np/octamer complex generated by single-particle cryoelectron microscopy, revealed that several intrinsically disordered tail domains of two NP pentamers, facing each other through their distal face, encage the histone octamer in a nucleosome-like conformation and prevent its dissociation. Formation of this complex depended on post-translational modification and exposure of the acidic tract at the tail domain of NP. Finally, NP was capable of transferring the histone octamers to DNA in vitro, assembling nucleosomes. This activity may have biological relevance for processes in which the histone octamer must be rapidly removed from or deposited onto the DNA., This work was supported by Agencia Española de Investigación/Fondos de Desarrollo Regional (AEI/FEDER, UE), [BFU2016-75984 to J.M.V., BFU2016-75983 to A.M.] and the Basque Government [IT709-13 to A.M.]

Salinity represents a critical environmental and an ecological factor in the reproduction of marine species. As global climate changes and anthropogenic factors affect salinity, in this study, we have analyzed the responses of Mytilus galloprovincialis spermatozoa to hyposaline stress. We exposed mussels, in laboratory tanks, for 24 hr at 18°C to control (35.9 psu) and three hyposaline (17.1, 22.6, and 26.2 psu) conditions, and evaluated the expression of sperm hsp70 and protamine-like proteins genes. Further we analyzed the electrophoretic pattern, the DNA binding and the release from sperm nuclei of protamine-like proteins. For all experimental approaches used, the results obtained at 17.1 psu condition were very similar to those obtained in the control condition, while alterations were always recorded at 22.6 and 26.2 psu conditions. Particularly, at 22.6 and 26.2 psu, was observed: 42.5- and 17.1-fold increase in hsp70 expression, respectively, and hypoexpression of PL-II/PLIV protamine-like proteins genes. Further, electrophoretic mobility shift assays and salt-induced release of nuclear proteins from sperm nuclei, revealed alterations in the PL proteins/DNA binding, in these two hyposaline conditions. The similarity between the results obtained in control and in the more severe hyposaline condition (17.1 psu) could indicate a phenomenon of fertility preservation strategy due to gamete plasticity.

Successful reproduction is a determining factor for the survival of species. In this century, major risks affecting reproductive health are for those species that fertilize externally, such as several marine invertebrates, since several marine ecosystems are polluted by different types of xenobiotics. Among the xenobiotics present in seawater, a relevant role is played by heavy metals whose release into the marine environment has increased their levels to large extents within the past few decades. Copper is one of the most interesting heavy metals, because in small quantities, it is essential, being involved in several physiological functions, such as redox reactions, oxygen transport, cellular respiration, free radical defense, neurotransmitter synthesis, and neuronal myelination, but can be toxic above certain threshold concentrations. In this study, we have evaluated the effects induced by 24 hr exposure to a subtoxic copper concentration on the reproductive system (gonads, spermatozoa, and protamine‐like proteins) of Mytilus galloprovincialis. Protamine‐like proteins represent the main basic protein component of sperm chromatin of this organism. After exposure, we found accumulation of this metal in gonads, spermatozoa, and protamine‐like proteins of exposed mussels, as indicated by inductively coupled plasma–mass spectrometry analyses. Moreover, altered expression levels of mt10 and protamine‐like proteins genes in spermatozoa and gonads, respectively, of exposed mussels were registered by real‐time polymerase chain reaction analyses. We analyzed also the DNA binding affinity of protamine‐like proteins extracted from spermatozoa of exposed mussels. The results showed a higher DNA binding affinity and a different DNA binding mode in exposed mussels. Moreover, an increased amount of NaCl was required for the release from sperm nuclei of PL‐III, the main protamine‐like proteins component. Interestingly, protamine‐like proteins extracted from spermatozoa of exposed mussels promoted DNA oxidative damage in the presence of H2O2. These results demonstrate that also tolerable copper amount could affect the properties of protamine‐like proteins and determine negative effects on Mytilus galloprovincialis reproductive system. Finally, these analyses could be useful to develop quick and efficient chromatin‐based genotoxicity tests for pollution biomonitoring programs.

This study aims to assess the effects induced by 24hr exposure to a subtoxic copper concentration on the reproductive system (gonads, spermatozoa, and protamine-like [PL] proteins) of Mytilus galloprovincialis. Inductively coupled plasma-mass spectrometry indicated accumulation of this metal in gonads, spermatozoa, and PL proteins of exposed mussels. Further, real-time polymerase chain reaction analyses showed altered expression levels of mt10 and PL proteins genes in spermatozoa and gonads, respectively, of exposed mussels. Protamine-like proteins, which represent the main basic component of sperm chromatin of this organism, showed a higher DNA binding affinity and a different DNA binding mode in exposed mussels. Moreover, an increased amount of NaCl was required for the release from sperm nuclei of PL-III, the main PL protein component. Finally, PL proteins extracted from exposed mussels promoted DNA oxidative damage in the presence of H O-2 (2.) These results demonstrate that the tolerable copper amount could also affect the properties of PL proteins and determine the negative effects on the reproductive system of this organism. These analyses could be useful to develop quick and efficient chromatin-based genotoxicity tests for pollution biomonitoring programs.

Climate changes are affecting species physiology, pushing environmental tolerance limits and shifting biogeographic distribution ranges of marine organisms. In addition to temperature and ocean acidification, global climate changes can also occur through changes in seawater salinity. Salinity levels may change also by anthropogenic factors such as mining activity and agricultural and industrial processes. Salinity is considered one of the most significant environmental stressors for marine bivalves. Mussels, in close proximity to coasts and in estuaries, in fact, periodically experience hypo-saline stress, particularly during intense precipitations. Many bivalve species, when experiencing water with high temperatures and low salinity, have the skill to acclimatize, or migrate to deeper water which is cooler and more saline. Mytilus galloprovincialis, is distributed in the north Atlantic Ocean, Mediterranean Sea and Black Sea and in recent years has invaded new places, including South Africa, Japan and California. This mussel is a common member of the intertidal estuarine and coastal areas where it can meet different salinities. Mytilus galloprovincialis can survive at elevated heat exposure, but it is susceptible to hyposalinity, while the native Pacific coast M. trossulus is more tolerant to hypo-saline conditions but vulnerable to heat stress. Since salinity represents a critical factor in reproduction of marine species, we analyzed the responses of Mytilus galloprovincialis spermatozoa to hyposaline stress. We exposed mussels, in laboratory tanks, for 24 hours at 18°C to control (35.9 psu) and three hyposaline (17.1; 22.6 and 26.2 psu) conditions, and evaluated the expression of sperm hsp70 and protamine-like proteins genes. Further we analyzed the electrophoretic pattern, the DNA binding and the release from sperm nuclei of protamine-like proteins. For all experimental approaches used, the results obtained at 17.1 psu condition were very similar to those obtained in control condition, while alterations were always recorded at 22.6 and 26.2 psu conditions. Particularly, at 22.6 and 26.2 psu, was observed: 42.5 and 17.1-fold increase in hsp70 expression, respectively and hypo-expression of PL-II/PLIV protamine-like proteins genes. Further, electrophoretic mobility shift assays and salt-induced release of nuclear proteins from sperm nuclei, revealed alterations in the PL proteins/DNA binding, in these two hyposaline conditions. The similarity between the results obtained in control and in the more severe hyposaline condition (17.1 psu) could indicate a phenomenon of fertility preservation strategy due to gamete plasticity.

International audience; Fertility is a growing healthcare issue for a rising number of cancer survivors. In men, cancer itself and its treatment can negatively affect spermatogenesis by targeting the dividing spermatogonia and their cellular environment, ultimately leading to a reduction of testicular germ cells and sperm count. Experimental data and prospective longitudinal studies have shown that sperm production can recover after cancer treatment. But despite this, yet unpredictable, recovery in sperm production, cancer survivors are more at risk to produce sperm with aneuploidy, DNA damage, abnormal chromatin structure, and epigenetic defects even 2 years post-treatment. Sperm DNA alteration is of clinical concern, as these patients may father children or seek assisted reproduction technologies (ART) using gametes with damaged genome that could result in adverse progeny outcomes. Interestingly, large cohort studies revealed lower birth rate but no significant impact on the health of the children born from male cancer survivors (naturally or using ART). Nevertheless, a better understanding of how cocktail of chemotherapy and new anticancer agents affect spermatogenesis and sperm quality is needed to reduce side effects. Moreover, developing new fertility preservation strategies is essential as sperm cryopreservation before treatment is currently the only option but does not apply for prepubertal/young postpubertal patients.

Protamine-like proteins (PL-II, PL-III and PL-IV) represent the major basic nuclear component of Mytilus galloprovincialis L sperm chromatin. The present study investigates the effects induced on the properties of PL-II protein after exposure of Mytilus galloprovincialis L for 24 h to 1.5 and 5 µM CdCl2. We found cadmium accumulation in protamine-like proteins with a linear grow up with the exposition dose. In particular, after 5 µM CdCl2 mussels exposure, the mobility of PL-II band changed in SDS-PAGE, suggesting structural rearrangement in presence of cadmium. Structural analysis using fluorescent probes, indicated that at 5 µM CdCl2 the complete conformational change of PL-II protein was reached. In the same condition of mussels exposure of 5 µM CdCl2, PL-II protein changed its DNA binding mode, which determined a closer DNA binding, because higher amount of NaCl were required for PL-II protein release by sperm nuclei. These results supported the hypothesis that mussel exposure to this CdCl2 dose, although lower to toxic ones, affects the properties of this protein and as a consequence chromatin organization of spermatozoa that is essential for the success of fertilization.

Due to socioeconomic factors, more couples are choosing to delay conception than ever. Increasing average maternal and paternal age in developed countries over the past 40 years has raised the question of how aging affects reproductive success of males and females. Since oxidative stress in the male reproductive tract increases with age, we investigated the impact of advanced paternal age on the integrity of sperm nucleus and reproductive success of males by using a Prdx6−/− mouse model. We compared sperm motility, cytoplasmic droplet retention sperm chromatin quality and reproductive outcomes of young (2-month-old), adult (8-month-old), and old (20-month-old) Prdx6−/− males with their age-matched wild type (WT) controls. Absence of PRDX6 caused age-dependent impairment of sperm motility and sperm maturation and increased sperm DNA fragmentation and oxidation as well as decreased sperm DNA compaction and protamination. Litter size, total number of litters and total number of pups per male were significantly lower in Prdx6−/− males compared to WT controls. These abnormal reproductive outcomes were severely affected by age in Prdx6−/− males. In conclusion, the advanced paternal age affects sperm chromatin integrity and fertility more severely in the absence of PRDX6, suggesting a protective role of PRDX6 in age-associated decline in the sperm quality and fertility in mice., Graphical abstract, Highlights • Absence of PRDX6 promotes increased levels of 8-OHdG in mouse spermatozoa. • Sperm DNA damage and impairment of sperm maturation and motility is exacerbated by the absence of PRDX6 in aging males. • Prdx6−/− fathers are subfertile producing smaller litters and pups with low birth weight compared to wild-type fathers. • PRDX6 is important to protect paternal DNA and sperm functions during aging.

International audience; BACKGROUND: Cryopreserved human sperm are used in assisted reproductive technology. However, the effect of cryopreservation on sperm DNA integrity is unclear.OBJECTIVES: The objectives of this study were to: (i) determine the impact of semen cryopreservation on human sperm DNA integrity and chromatin structure; (ii) test if parameters obtained from TUNEL and SCSA® correlate; and (iii) verify correlation between sperm motility, morphology and viability with TUNEL and SCSA® parameters.MATERIALS AND METHODS: Men attending a fertility clinic were recruited and grouped according to their sperm parameters (n = 9/group): normozoospermia, oligoasthenoteratozoospermia and teratozoospermia. Each semen sample was processed as follow: (i) directly frozen at -80 °C; (ii) diluted in Sperm Maintenance Medium, cooled for 30 min at 4 °C and frozen at -80 °C; (iii) diluted in Sperm Maintenance Medium; or (iv) in SpermFreeze. Each mixture from method (iii) and (iv) was then suspended for 30 min in liquid nitrogen vapor and plunged into liquid nitrogen. After at least two months of storage, samples were thawed at room temperature and analyzed for motility and viability, TUNEL and SCSA® assays.RESULTS: Progressive motility and viability decreased after freeze-thawing. TUNEL scores increased significantly in all samples after freezing-thawing while no significant change in the DNA fragmentation index (DFI) from SCSA® was observed. No change in the percentage high DNA stainability (HDS) was observed in normozoospermic samples; however it was significantly increased in all the methods in oligoasthenoteratozoospermic and in the methods (ii)-(iv) in teratozoospermic samples. The DFI and TUNEL scores correlated significantly with each other and inversely with sperm motility, viability and morphology.DISCUSSION AND CONCLUSION: Cryopreservation seems to be deleterious for the integrity of human sperm DNA and compaction. However, the sperm DFI was not affected during cryopreservation under the various methods of storage tested. Clinicians and investigators should take this information into consideration when using cryopreserved sperm for assisted reproduction.

Evidence is increasing that the integrity of sperm DNA may also be related to implantation failure and recurrent miscarriage (RM). To investigate this, the sperm DNA fragmentation in partners of 35 women with recurrent implantation failure (RIF) following in vitro fertilization, 16 women diagnosed with RM and seven recent fathers (control) were examined. Sperm were examined pre- and post-density centrifugation by the sperm chromatin dispersion (SCD) test and the terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. There were no significant differences in the age of either partner or sperm concentration, motility or morphology between three groups. Moreover, there were no obvious differences in sperm DNA fragmentation measured by either test. However, whilst on average sperm DNA fragmentation in all groups was statistically lower in prepared sperm when measured by the SCD test, this was not seen with the results from the TUNEL assay. These results do not support the hypothesis that sperm DNA fragmentation is an important cause of RIF or RM, or that sperm DNA integrity testing has value in such patients. It also highlights significant differences between test methodologies and sperm preparation methods in interpreting the data from sperm DNA fragmentation tests.

Testicular varicocele, a dilation of the veins of the pampiniform plexus thought to increase testicular temperature via venous congestion, is commonly associated with male infertility. Significant study has clarified the negative impact of varicocele on semen parameters and more recent work has shed light on its detrimental effects on the molecular and ultrastructural features of sperm and the testicular microenvironment, as well as more clearly defined the positive impacts of treatment on couples’ fertility. The relationship between varicocele and testicular endocrine function, while known for some time based on histologic evaluation, has become more apparent in the clinical setting with a growing link between varicocele and hypogonadism. Finally, in the pediatric setting, while future study will clarify the impact of varicocele on fertility and testicular function, recent work supports a parallel effect of varicocele in adolescents and adults, suggesting a re-evaluation of current treatment approaches in light of the progressive nature of the condition and potential increased risk of future disease.

Ezrin, radixin, moesin and merlin (ERM) proteins are highly homologous actin-binding proteins that share extensive sequence similarity with each other. These proteins tether integral membrane proteins and their cytoplasmic peripheral proteins (e.g., adaptors, nonreceptor protein kinases and phosphatases) to the microfilaments of actin-based cytoskeleton. Thus, these proteins are crucial to confer integrity of the apical membrane domain and its associated junctional complex, namely the tight junction and the adherens junction. Since ectoplasmic specialization (ES) is an F-actin-rich testis-specific anchoring junction-a highly dynamic ultrastructure in the seminiferous epithelium due to continuous transport of germ cells, in particular spermatids, across the epithelium during the epithelial cycle-it is conceivable that ERM proteins are playing an active role in these events. Although these proteins were first reported almost 25 years and have since been extensively studied in multiple epithelia/endothelia, few reports are found in the literature to examine their role in the actin filament bundles at the ES. Studies have shown that ezrin is also a constituent protein of the actin-based tunneling nanotubes (TNT) also known as intercellular bridges, which are transient cytoplasmic tubular ultrastructures that transport signals, molecules and even organelles between adjacent and distant cells in an epithelium to coordinate cell events that occur across an epithelium. Herein, we critically evaluate recent data on ERM in light of recent findings in the field in particular ezrin regarding its role in actin dynamics at the ES in the testis, illustrating additional studies are warranted to examine its physiological significance in spermatogenesis.

In mammals, sperm guidance in the oviduct appears essential for successful sperm arrival at the oocyte. Hitherto, three different potential sperm guidance mechanisms have been recognized: thermotaxis, rheotaxis, and chemotaxis, each of them using specific stimuli - a temperature gradient, fluid flow, and a chemoattractant gradient, respectively. Here, we review sperm behavioral in these mechanisms and indicate commonalities and differences between them.

The sperm DNA damage may occur in testis, genital ducts, and also after ejaculation. Mechanisms altering chromatin remodeling are abortive apoptosis and oxidative stress resulting from reactive oxygen species. Three classifications of intratesticular, post-testicular, and external factors have been correlated with increased levels of human sperm DNA damage which can affect the potential of fertility. Lifestyle, environment, medical, and iatrogenic factors might be considered to cause dysmetabolism to make distracting interactions and endocrine disrupting compounds. As a result, these may induce chromatin/DNA alteration in germ cells, which may be transmitted across generations with phenotypic consequences. Alcohol consumption may not increase the rate of sperm residual histones and protamine deficiency; however, it causes an increase in the percentage of spermatozoa with DNA fragmentation and apoptosis. In a medical problem as spinal cord injury, poor semen parameters and sperm DNA damage were reported. Infection induces reactive oxygen species production, decreases the total antioxidant capacity and sperm DNA fragmentation or antigen production that lead to sperm dysfunctions and DNA fragmentation. While reactive oxygen species generation increases with age, oxidative stress may be responsible for the age-dependent sperm DNA damage. The exposing of reproductive organs in older men to oxidative stress for a long time may produce more DNA-damaged spermatozoa than youngers. Examining the sperm chromatin quality in testicular cancer and Hodgkin’s lymphoma patients prior to chemotherapy demonstrated the high incidence of DNA damage and low compaction in spermatozoa at the time of the diagnosis. In chemotherapy cycle with genotoxic agents in cancer patients, an increase in sperm DNA damage was shown after treatment. In overall, those factors occurring during the prenatal or the adult life alter the distribution of proteins associated with sperm chromatin induce changes in germ cells which can be detected in infertile patients.

The sperm nucleus is prone to sustain DNA damage before and after ejaculation. Distribution of the damage is not homogeneous, and the factors determining differential sensitivity among nuclear regions have not yet been characterized. Human sperm chromatin contains three structural domains, two of which are considered the most susceptible to DNA damage: the histone bound domain, harboring developmental related genes, and the domain associated with nuclear matrix proteins. Using a quantitative polymerase chain reaction (qPCR) approach, we analyzed the number of lesions in genes homeobox A3 (HOXA3), homeobox B5 (HOXB5), sex-determining region Y (SRY)-box 2 (SOX2), β-GLOBIN, rDNA 18S, and rDNA 28S in human sperm after ultraviolet irradiation (400 μW cm−2, 10 min), H2O2 treatment (250 mmol l−1, 20 min), and cryopreservation, which showed differential susceptibility to genetic damage. Differential vulnerability is dependent on the genotoxic agent and independent of the sperm nuclear proteins to which the chromatin is bound and of accessibility to the transcription machinery. Immunodetection of 8-hydroxy-2'-deoxyguanosine (8-OHdG) showed that the highest level of oxidation was observed after H2O2 treatment. The distribution of oxidative lesions also differed depending on the genotoxic agent. 8-OHdG did not colocalize either with histone 3 (H3) or with type IIα + β topoisomerase (TOPO IIα + β) after H2O2 treatment but matched perfectly with peroxiredoxin 6 (PRDX6), which is involved in H2O2 metabolism. Our study reveals that the characteristics of the sperm head domains are responsible for access of the genotoxicants and cause differential degree of damage to nuclear areas, whereas chromatin packaging has a very limited relevance. The histone-enriched genes analyzed cannot be used as biomarkers of oxidative DNA damage.

The traditional study of spermogram readings is a main method for examination of male infertility. However, the spermogram readings may be considerably covered in the group of fertile and infertile men and fail to give a full insight into sperm fertilizing ability. In recent years, tests determining the functional properties of sperm have been intensively developed. This review considers a quantitative electron microscopic technique of sperm (EMTS), which assesses the structure and function of the sperm penetration and motor apparatus. The detection of sperm chromatin structural disorders can understand the causes of early embryonic malformation. Indications for EMTS and interpretation of its results are given.

The paper considers the topical problems of the etiopathogenesis, diagnosis, prevention, and treatment of male reproductive dysfunction, by using an interdisciplinary approach in view of clinical, organizational, and methodical aspects. It proposes a three-level care system for men from childless couples. Current requirements for andrology laboratory equipment and sperm quality assessment methods are shown. Identification of 3 steps of comprehensive prevention of male reproductive dysfunction is substantiated.

In this study annual fluctuations of DNA fragmentation and quality of cold-stored equine sperm were evaluated. Ejaculates were collected weekly during one year from 15 stallions. Ejaculate volume, sperm concentration and total sperm count were determined and semen was then extended and cold-stored for 48 h. Sperm motility was evaluated by CASA before and after 24 as well as 48 h of cold storage. In addition, the percentages of sperm with intact plasma membrane and acrosome (PMAI %) and with low intracellular Ca2+ level were determined in cold-stored semen (24 h, 48 h). SCSA™ was performed to assess mean DFI, SD of DFI and % DFI in raw frozen-thawed as well as in extended sperm after 24 and 48 h of storage. The month of semen collection affected (P < 0.05) all parameters evaluated in raw semen and all criteria except progressive motility as well as rapid cells in semen stored for 24 and 48 h, respectively. Ejaculate volume was higher and sperm concentration lower in summer compared to winter and motility lower in July than in any other month of the year (P < 0.05). In semen processed in April and stored for 24 h the percentage of rapid cells was improved compared to January and after 48 h of storage progressive motility (%) was higher in January and October than in July (P < 0.05). After 24 h of cold storage PMAI % was higher in October than in January and after 48 h values were higher in September compared to January and February as well as from April to July (P < 0.05). Regarding sperm with low intracellular Ca+2 level (%) after storage for 24 and 48 h, higher values were measured in winter and in October compared to April, June and July (P < 0.01). Seasonal changes in DNA fragmentation were most evident with respect to mean DFI. In raw frozen-thawed semen mean DFI was lower from August to November than in June and July (P < 0.001). Values were lower during winter compared to spring and early summer (P < 0.05) and lower in December than from April to September (P < 0.001). After 24 h of cold storage mean DFI was lower in September and October when compared to January, February, May, July and November (P < 0.05) and after 48 h storage mean DFI was reduced in spring and autumn compared to February, June and July (P < 0.05). In conclusion, a seasonal effect was evident on semen characteristics of raw and cold-stored sperm. Semen quality was impaired in midsummer when low sperm motility and viability were combined with an elevated DNA fragmentation and Ca2+ level of sperm.

The study of the sperm proteins is crucial for understanding its normal function and alterations in infertile patients. The sperm is a highly specialized cell with a very large flagella, with little cytoplasm and a highly condensed nucleus. The most abundant proteins in the nucleus of mammalian sperm are the protamines. The main functions of the protamines are the condensation of the DNA, possibly contributing to the generation of a more hydrodynamic sperm head and to the protection of the genetic message. However, in addition to protamines, about 5.0-15.0% of the paternal genome is also complexed with histones and histone variants. It has also demonstrated a differential distribution of genes in regions associated with histone and protamine-associated regions, suggesting a potential epigenetic relevance in embryonic development. More recently, detailed lists of proteins have been described corresponding to the different compartments of the sperm cell thanks to the application of recent proteomic techniques based on mass spectrometry (MS). Differential proteomics is also being applied to identify the presence of protein abnormalities found in infertile patients

The aim of this study was to determine the percentage of sperm with damaged chromatic measure with toluidine blue stain and it´s relationship with motility and viability in criopreserverd semen from Brahman bulls. Three ejaculates from six Brahman bulls were used. Immediately after thawing, sperms were stained with toluidine blue to establish chromatin integrity (sperms with normal chromatin were light blue or green while sperms with damaged chromatin were dark blue or violet). Sperms were also stained with eosin-nigrosin to determine viability (live sperms were unstained while dead sperms were pink). Motility was measured under light microscope. Effects of bull, ejaculate, and the interaction between variables were assessed. The percentage of live sperms was 50.02 ( ± 14.13%). The mean motility was 33.88 (± 12.43%), while the percentage of sperms with damaged chromatin was 4.17 ( ± 2.96%). Viability was positively correlated with motility (r=0.77217, p=0.0002), and negatively correlated with damaged chromatin sperms (r= -0.43104, p=0.0087). Motility percentage was negatively correlated with the percentage of sperms with damaged chromatin (r=-0.48337, p=0.0421). In conclusion, cryopreserved semen of Brahman bulls presented a low level of chromatin damage, and this trait was negatively correlated with sperm motility and viability.El objetivo del presente trabajo fue determinar el porcentaje de espermatozoides con cromatina dañada medida con la tinción de azul de toluidina, y su relación con la motilidad y la vitalidad del semen criopreservado de toros Brahma. Para ello, se utilizó semen de tres eyaculados de seis toros Brahman, el cual una vez descongelado se procedió a teñir con azul de toluidina para determinar la integridad de la cromatina (espermatozoides con cromatina normal teñidos de azul o verde claro; espermatozoides con cromatina anormal teñidos de azul oscuro o violeta), también se tiñeron con eosinanigrosina para determinar la viabilidad (espermatozoides vivos permanecen blancos; espermatozoides muertos se tiñen de rosado) y se estimó la motilidad espermática mediante microscopía óptica. Se evidenciaron las diferencias en todos los parámetros evaluados debidas al efecto toro y al eyaculado, así como a la interacción entre estas dos variables. El porcentaje de espermatozoides vivos fue de 50.02 ± 14.13% y la motilidad espermática promedió un 33.88 ± 12.43%, mientras que el porcentaje de espermatozoides con cromatina dañada fue de 4.17 ± 2.96%. El porcentaje de espermatozoides vivos se correlacionó positivamente con la motilidad (r=0.77217, p=0.0002), y negativamente con el porcentaje de espermatozoides con cromatina dañada (r= -0.43104, p=0.0087), mientras que el porcentaje de motilidad se correlacionó negativamente con el porcentaje de espermatozoides con cromatina anormal (r= -0.48337, p=0.0421). En conclusión, el semen criopreservado de toros Brahman presenta un bajo nivel de espermatozoides con daño en la cromatina, lo cual se correlaciona negativamente con la motilidad y la vitalidad espermática.O objectivo deste estudo foi determinar a percentagem de espermatozóides com cromatina danificada, determinada pela coloração com azul de toluidina e sua relação com a viabilidade e a mobilidade do esperma cripreservado de touros Brahman. Para isso, foram utilizados três ejaculados de sêmen de seis touros Brahman, que uma vez descongelado foram coradas com azul de toluidina para determinar a integridade da cromatina (espermatozóides com cromatina normal coloream de azul ou verde; cromatina de espermatozóides con cromatina danificada, coloream de azul escuro ou violeta). Também foram corados com eosina nigrosina para determinar a viabilidade (espermatozóides vivos permanecem brancos e os mortos de cor rosa) e a motilidade espermática foi estimada por microscopia de luz. Foram encontradas diferenças significativas em todos os parâmetros, devido ao efeito de touro e o ejaculado, bem como a interacção entre essas duas variáveis. A percentagem de espermatozóides vivos foi de 50.02 ± 14.13% e motilidade espermática média de 33.88 ± 12.43%, enquanto a percentagem de espermatozóides com cromatina danificada foi de 4.17 ± 2.96%. A percentagem de espermatozóides vivos foi positivamente correlacionada com a motilidade (r=0.77217, p=0.0002) e negativamente com a porcentagem de espermatozóides com cromatina danificada (r = -0.43104, p= 0.0087), enquanto que a percentagem de motilidade correlacionou negativamente com a percentagem de espermatozóides com cromatina danificada (r = -0.48337, p=0.0421). Em conclusão, o sêmen de touros Brahman criopreservados tem um baixo nível de dano da cromatina, que está correlacionada negativamente com a motilidade e a vitalidade do esperma.

The potential protective effect of catalase supplementation during in vitro culture of frozen/thawed bull spermatozoa was investigated. Frozen/thawed semen collected from three fighting bulls was diluted in phosphate buffered saline (PBS) and incubated at 37 °C under different experimental conditions: Control, Catalase (CAT) (200 U/mL), Oxidant (OXI) (100 μm Fe2+/1 mm ascorbate), and Catalase + Oxidant (CAT/OXI). We assessed sperm motility, acrosomal integrity, viability and chromatin status (SCSA®) at 0, 2 and 6 h of incubation. Our results showed that catalase abolished the effect of the oxidant, protecting spermatozoa against reactive oxygen species, and improving both sperm motility and chromatin status during incubation. The OXI treatment significantly reduced the percentage of motile sperm after 6 h of incubation. The statistical model also showed that there were differences in sperm motility between CAT/OXI (20.8 ± 2.9%) and OXI (11.6 ± 7.6%) (p, This study has been supported by the Spanish Ministry of Education and Science (AGL2004-05904GAN) and by the Council for Education and Science of Junta de Castilla-La Mancha (PAC-06-047). Felipe Martinez-Pastor was supported by the ‘Juan de la Cierva’ program (Spanish Ministry of Education and Science).

Background The aim of present study is to evaluate the effect of PolyVinyl Pyrrolidone (PVP) routinly used during ICSI procedure on sperm membrane integrity, and sperm chromatin status. Materials and methods This study was carried out on 21 semen samples from the infertile men referring to Isfahan Fertility and Infertility Center. The processed semen samples were divided into two portions. One portion was added to Ham’s F10+ 10% PVP, and the other portion was added to Ham’s F10 as a control group. Hypo-osmotic swelling test (HOST), SDS, and SDS+EDTA tests were carried out on the control and PVP groups at 15, 30, and 60min. Results The results show that sperm membrane integrity measured by HOST, and sperm chromatin stability measured by SDS test, reduces by increasing the exposure time to PVP. However, the ability of sperm chromatin undergoing decondensation (that has been assessed by SDS+EDTA), does not show any changes by increasing the exposure time to PVP. Conclusion The results of current study shows that reducing the exposure time of sperm to PVP may protect sperm membrane, and chromatin integrity.

El propósito de este estudio fue cuantificar la presencia de espermatozoides con cromatina dañada e inmadura en el semen criopreservado de toros Brahman. Para ello, frotis de tres eyaculados de cinco toros fueron teñidos con azul de toluidina (AT) y azul de anilina (AN) para evaluar integridad y la inmadurez de la cromatina, respectivamente. Los espermatozoides teñidos con AT fueron considerados espermatozoides con cromatina normal (teñidos de azul claro) o con cromatina dañada (teñidos de azul oscuro o violeta), mientras que los teñidos con AN fueron clasificados como maduros (no teñidos) o inmaduros (teñidos de azul). El porcentaje de espermatozoides con cromatina dañada fue de 7,0 ± 3,71; rango entre 3 y 17,5%. Se observaron efectos del toro y el eyaculado sobre el porcentaje de espermatozoides con cromatina dañada (P

A strategy to circumvent the poor polyphenols bioavailability is to load these compounds into liposomes. We evaluated the in vitro effects of quercetin (Q) and Q-loaded liposomes (QLL, 30, 50, 100 ?M) on motility, viability and chromatin integrity of swim-up selected human sperm. Antioxidant power was assayed against tert-butylhydroperoxide induced lipid peroxidation (LPO) using C11-BODIPY581/591 fluorescent probe and transmission electron microscopy. QLL showed decreased toxicity for sperm motility and viability and increased DNA damage compared to Q. The percentage of sperm with fluorescence, marker of LPO, was decreased in samples incubated with Q vs QLL (P < 0.001). The ultrastructure of acrosomes and membranes was preserved with Q 30/100 ?M, whereas QLL did not prevent membrane injury.Q alone appeared more effective than Q incorporated into liposomes; however liposomes could be considered as carriers that may convey different compounds inside sperm; they may therefore represent a field of research rich of many applications.

Introduction: Different studies have shown that there is no relation between sperm chromatin stability and fertilization rate in both IVF and ICSI patients. However, the relation between SDS tests, as a detergent, along with DTT as reducer of disulphide bridges has not been studied so far in ICSI patients. Since different concentrations of DTT can induce different degrees of sperm chromatin decondensation, the aim of this study was to evaluate the effect of different concentrations of DTT on sperm chromatin decondensation in IVF and ICSI cases. Methods: During this study, 85 patients were divided into two groups according to their treatment procedure (IVF or ICSI).Semen samples of each patient was evaluated for sperm chromatin tests including SDS, SDS+EDTA & SDS+DTT for assessment of free thiole groups level (-SH), amount of non covalent bond between Zn and thioles(-SH Zn SH-) and levels of disulfide bond (-S-S-) in sperm chromatin, respectively. In this study, seminal fructose concentration, corrected seminal fructose level and true corrected fructose level as indicators of seminal vesicle function on sperm chromatin stability were assessed. Results: No correlation was observed between any of the above tests and rate of fertilization, both in IVF and ICSI cases. However, in IVF patients, a significant correlation was observed between SDS, SDS+DTT test and seminal fructose level, while in ICSI patients, only a significant correlation was observed between SDS+DTT and corrected or true fructose concentration. Conclusion: Since no correlation was observed between sperm chromatin test and fertilization rate, it is suggested that the chromatin status of these samples are adequate for fertilization to take place and extent of disulphide bridges has no effect on fertilization rate. However, the amount of disulphide bound present in sperms of ICSI and IVF patients are different, and this difference is related to seminal vesicle performance in these patients.

Background Sperm DNA integrity is essential for the accurate transmission of genetic information. The clinical significance of this assessment lies in its association with not only natural conception rates, but also the success of assisted reproduction technology (ART). It has been reported that sperm chromatin structure assay (SCSA) identified thresholds for negative pregnancy outcome after ART when the DNA fragmentation index (DFI), previously known as COMPalphat, was >30%. Methods In a prospective clinical study, we examined 34 male infertile patients, the husbands of women undergoing conventional IVF or ICSI. SCSA and ART were carried out on semen aliquots taken from the same ejaculate. Fertilization rate, embryo quality and pregnancy rates were correlated to SCSA parameters, DFI and highly DNA stainable (HDS) cells. Results No differences were seen in SCSA parameter values between patients initiating pregnancies and not doing so in either ICSI or conventional IVF. Pregnancies and normal delivery were obtained even with high levels of DFI. Conclusions There is still controversy over whether analytical techniques currently in use are able to identify the level of damage to spermatozoa. Large-scale studies should be conducted in different clinical settings to determine the effects of sperm DNA damage on the outcome of ART.

Purpose : We have carried out experiments to determine if human cervical mucus can act as an in vitro selective barrier against spermatozoa morphologically normal that carry genetic structural abnormalities. Methods : Sperm chromatin abnormalities have been evaluated by Chromomycin A3 and “endogenous” nick translation. Results : The data obtained have shown that spermatozoa possessing higher levels of DNA protamination are more proficient in crossing the cervical mucus barrier. Moreover, the levels of positivity to endogenous nick translation treatment was practically zero in such spermatozoa. Conclusions : We suggest that sperm penetration of cervical mucus could be used to select sperm preparations free of fragmented DNA or chromatin structural abnormalities for assisted reproduction.

A natural disaster leading to accumulation of environmental contaminants may have substantial effects on the male reproductive system. Our aim was to compare and assess semen parameters in a normospermic population residing in the Southern Louisiana, USA area pre- and post-Hurricane Katrina. We retrospectively evaluated semen analyses data (n = 3452) of 1855 patients who attended the Tulane University Andrology/Fertility Clinic between 1999 and 2013. The study inclusion criteria were men whose semen analyses showed ≥ 1.5 ml volume; ≥15 million ml -1 sperm concentration; ≥39 million total sperm count; ≥40% motility; >30% morphology, with an abstinence interval of 2-7 days. After the inclusion criteria applied to the population, 367 normospermic patients were included in the study. Descriptive statistics and group-based analyses were performed to interpret the differences between the pre-Katrina (Group 1, 1999-2005) and the post-Katrina (Group 2, 2006-2013) populations. There were significant differences in motility, morphology, number of white blood cell, immature germ cell count, pH and presence of sperm agglutination, but surprisingly there were no significant differences in sperm count between the two populations. This long-term comparative analysis further documents that a major natural disaster with its accompanied environmental issues can influence certain semen parameters (e.g., motility and morphology) and, by extension, fertility potential of the population of such areas.

PubMed: 25673563, During fertilization, spermatozoa make essential contributions to embryo development by providing oocyte activating factors, centrosomal components, and paternal chromosomes. Protamines are essential for proper packaging of sperm DNA; however, in contrast to the studies of oocyte-related female infertility, the influence of sperm chromatin structure on male infertility has not been evaluated extensively. The objective of this study was to determine the sperm chromatin content of bull spermatozoa by evaluating DNA fragmentation, chromatin maturity/protamination, PRM1 protein status, and nuclear shape in spermatozoa from bulls with different fertility. Relationships between protamine 1 (PRM1) and the chromatin integrity were ascertained in spermatozoa from Holstein bulls with varied (high vs. low) but acceptable fertility. Sperm DNA fragmentation and chromatin maturity (protamination) were tested using Halomax assay and toluidine blue staining, respectively. The PRM1 content was assayed using Western blotting and in-gel densitometry, flow cytometry, and immunocytochemistry. Fragmentation of DNA was increased and chromatin maturity significantly reduced in spermatozoa from low-fertility bulls compared to those from high-fertility bulls. Field fertility scores of the bulls were negatively correlated with the percentage of spermatozoa displaying reduced protamination and fragmented DNA using toluidine blue and Halomax, respectively. Bull fertility was also positively correlated with PRM1 content by Western blotting and flow cytometry. However, detection of PRM1 content by Western blotting alone was not predictive of bull fertility. In immunocytochemistry, abnormal spermatozoa showed either a lack of PRM1 or scattered localization in the apical/acrosomal region of the nuclei. The nuclear shape was distorted in spermatozoa from low-fertility bulls. In conclusion, we showed that inadequate amount and localization of PRM1 were associated with defects in sperm chromatin structure, coinciding with reduced fertility in bulls. These findings are highly significant because they reveal molecular and morphological phenotypes of mammalian spermatozoa that influence fertility. © 2015 by the Society for the Study of Reproduction, Inc.

Background: Currently, relation between reactive oxygen species (ROS) ROS concentration and semen quality was indicated. Saffron has traditionally been not only considered as a food additive but also as a medicinal herb, which has a good antioxidant properties. Objective: The aim of this study was to evaluate the protection potency of saffron and vitamin E on sperm chromatin integrity. Materials and Methods: Thirty adult male Wistar rats divided equally into saffron (100 mg/kg), vitamin E (100 mg/kg) and control (0.5cc distilled water /day) groups. After 60 days, cauda epididymis dissected and sperm cells were used for analysis of sperm chromatin packaging by chromomycin A3 (CMA3) staining, and sperm chromatin susceptibility to acid denaturation by acridine orange (AO) staining. Results: The mean percentage of CMA3 positive sperm was significantly decreased in saffron and vitamin E groups relative to control group (p

Introduced in 2001, intracytoplasmic morphologically selected sperm injection (IMSI) represents a more sophisticated way of ICSI whereby, prior to injection, the spermatozoon is selected at higher magnification. Doing so, the spermatozoon can be evaluated for fine integrity of its nucleus and the injection of a normal spermatozoon with a vacuole-free head can be assured. Additional research is needed to unravel the underlying mechanisms responsible for the presence of vacuoles in sperm heads. Associations with acrosome status, chromatin condensation, DNA fragmentation and sperm aneuploidy have been documented, however, controversy on their nature exists. Spermatozoon shape and large vacuoles are detected and deselected in conventional ICSI as well. However, the detection of subtle small vacuoles depends on the resolving power of the optical system and may impact oocyte fertilization, embryo development and implantation. Several comparative studies have indicated that the use of high-magnification sperm selection was associated with both higher pregnancy and delivery rates, whereas also lower miscarriage rates were observed. However, still to date randomized, well-powered studies to confirm these findings are scarce and show conflicting results. Hence, the most relevant indications for IMSI still remain to be determined. Two groups of patients have been put forward i.e. severe male-factor infertility patients and patients with a history of repeated ICSI failures. However, for both groups limited to no proof of any benefit does exist. IMSI is a time-consuming procedure at the expense of oocyte ageing. The lack of proof and understanding of its benefit does not justify its routine clinical application at present.

In this study we investigated whether morphology and chromatin anomalies in human spermatozoa can influence fertilization after intracytoplasmic sperm injection (ICSI). We examined unfertilized oocytes, using the fluorochrome Hoechst 33342, to determine whether a relationship exists between failure of fertilization and sperm chromatin quality. Sperm chromatin packaging quality was assessed using the chromomycin A3 (CMA3) fluorochrome, and the presence of DNA damage in spermatozoa, using in-situ nick translation, Normal males present sperm parameters with a normal morphology of > 20%, CMA3 fluorescence of < 30% and exhibit endogenous nicks in < 10% of their spermatozoa. When patients were separated according to these values no difference was observed in their fertilization rates after ICSI. When the unfertilized ICSI oocytes were examined, we found that patients with CMA3 fluorescence of