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1.
Int J Mol Sci ; 25(8)2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38674066

RESUMO

Several clinical laboratories assess sperm DNA fragmentation (sDF) in addition to semen analysis in male infertility diagnosis. Among tests evaluating sDF, TUNEL (Terminal deoxynucleotidyl transferase dUTP nick end labeling) and SCD (Sperm Chromatin Dispersion) are widely used. Our lab developed a modified version of TUNEL (TUNEL/PI) able to distinguish two sperm populations (PI Brighter and PI Dimmer) differently associated with sperm viability and reproductive outcomes. The aim of this study was to compare sDF levels detected by SCD and TUNEL/PI in the semen samples from 71 male subjects attending our Andrology Laboratory. Our results demonstrate that SCD is less sensitive in determining sDF compared to TUNEL/PI. The statistically significant positive correlation found between sDF evaluated by SCD and PI Dimmer (consisting of all dead spermatozoa) suggests that SCD mainly detects sDF in unviable spermatozoa. We confirmed that most spermatozoa detected by SCD are unviable by performing SCD after incubation in hypo-osmotic medium to discriminate viable and unviable cells in 52 samples. Such results might explain the lower ability of this test in discriminating couples having successful ART outcomes demonstrated in published metanalyses. Overall, our results indicate that SCD is less sensitive in evaluating sDF for diagnostic purposes.


Assuntos
Cromatina , Fragmentação do DNA , Marcação In Situ das Extremidades Cortadas , Análise do Sêmen , Espermatozoides , Masculino , Humanos , Espermatozoides/metabolismo , Cromatina/metabolismo , Marcação In Situ das Extremidades Cortadas/métodos , Análise do Sêmen/métodos , Adulto , Infertilidade Masculina/diagnóstico , Infertilidade Masculina/genética
2.
Neurobiol Learn Mem ; 203: 107776, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37236300

RESUMO

The contextual fear conditioning (CFC) paradigm is the most productive approach for understanding the neurobiology of learning and memory as it allows to follow the evolution of memory traces of a conditioned stimulus and a specific context. The formation of long-term memory involves alterations in synaptic efficacy and neural transmission. It is known that the prefrontal cortex (PFC) exerts top-down control over subcortical structures to regulate behavioural responses. Moreover, cerebellar structures are involved in storing conditioned responses. The purpose of this research was to determine if the response to conditioning and stressful challenge is associated with alterations in synapse-related genes mRNA levels in the PFC, cerebellar vermis (V), and hemispheres (H) of young adult male rats. Four groups of Wistar rats were examined: naïve, CFC, shock only (SO), and exploration (EXPL). The behavioural response was evaluated by measuring the total freezing duration. Real-Time PCR was employed to quantify mRNA levels of some genes involved in synaptic plasticity. The results obtained from this study showed alterations in gene expression in different synapse-related genes after exposure to stressful stimuli and positioning to new environment. In conclusion, conditioning behavioural stimuli change the expression profile of molecules involved in neural transmission.


Assuntos
Vermis Cerebelar , Córtex Pré-Frontal , Ratos , Masculino , Animais , Ratos Wistar , Córtex Pré-Frontal/fisiologia , Sinapses , Medo/fisiologia , Expressão Gênica , RNA Mensageiro/metabolismo
3.
Int J Mol Sci ; 24(5)2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36902084

RESUMO

Cryopreservation is an expanding strategy to allow not only fertility preservation for individuals who need such procedures because of gonadotoxic treatments, active duty in dangerous occupations or social reasons and gamete donation for couples where conception is denied, but also for animal breeding and preservation of endangered animal species. Despite the improvement in semen cryopreservation techniques and the worldwide expansion of semen banks, damage to spermatozoa and the consequent impairment of its functions still remain unsolved problems, conditioning the choice of the technique in assisted reproduction procedures. Although many studies have attempted to find solutions to limit sperm damage following cryopreservation and identify possible markers of damage susceptibility, active research in this field is still required in order to optimize the process. Here, we review the available evidence regarding structural, molecular and functional damage occurring in cryopreserved human spermatozoa and the possible strategies to prevent it and optimize the procedures. Finally, we review the results on assisted reproduction technique (ARTs) outcomes following the use of cryopreserved spermatozoa.


Assuntos
Preservação da Fertilidade , Preservação do Sêmen , Animais , Humanos , Masculino , Sêmen , Preservação do Sêmen/métodos , Espermatozoides , Criopreservação/métodos , Preservação da Fertilidade/métodos , Motilidade dos Espermatozoides
4.
Int J Mol Sci ; 24(19)2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37833859

RESUMO

Benzo(a)pyrene (BaP) is considered one of the most dangerous air pollutants for adverse health effects, including reproductive toxicity. It is found both in male and female reproductive fluids likely affecting spermatozoa after the selection process through cervical mucus, a process mimicked in vitro with the swim-up procedure. In vitro effects of BaP (1, 5, 10 µM) were evaluated both in unselected and swim-up selected spermatozoa after 3 and 24 h of incubation. BaP reduced total, progressive and hyperactivated motility and migration in a viscous medium both in swim-up selected and unselected spermatozoa. Viability was not significantly affected in swim-up selected but was reduced in unselected spermatozoa. In swim-up selected spermatozoa, increases in the percentage of spontaneous acrosome reaction and DNA fragmentation were observed after 24 h of incubation, whereas no differences between the control and BaP-treated samples were observed in caspase-3 and -7 activity, indicating no effects on apoptotic pathways. ROS species, evaluated by staining with CellROX® Orange and Dihydroethidium, did not differ in viable spermatozoa after BaP treatment. Conversely, the percentage of unviable ROS-positive spermatozoa increased. Our study suggests that BaP present in male and female genital fluids may heavily affect reproductive functions of human spermatozoa.


Assuntos
Benzo(a)pireno , Motilidade dos Espermatozoides , Humanos , Masculino , Feminino , Benzo(a)pireno/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Sementes/metabolismo , Espermatozoides/metabolismo
5.
Hum Reprod ; 37(11): 2497-2502, 2022 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-36112046

RESUMO

Biomedical science is rapidly developing in terms of more transparency, openness and reproducibility of scientific publications. This is even more important for all studies that are based on results from basic semen examination. Recently two concordant documents have been published: the 6th edition of the WHO Laboratory Manual for the Examination and Processing of Human Semen, and the International Standard ISO 23162:2021. With these tools, we propose that authors should be instructed to follow these laboratory methods in order to publish studies in peer-reviewed journals, preferable by using a checklist as suggested in an Appendix to this article.


Assuntos
Análise do Sêmen , Sêmen , Humanos , Reprodutibilidade dos Testes , Análise do Sêmen/métodos , Revisão por Pares , Editoração
6.
Int J Mol Sci ; 22(18)2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34576161

RESUMO

Several psychiatric conditions such as phobias, generalized anxiety, and post-traumatic stress disorder (PTSD) are characterized by pathological fear and anxiety. The main therapeutic approach used in the management of these disorders is exposure-based therapy, which is conceptually based upon fear extinction with the formation of a new safe memory association, allowing the reduction in behavioral conditioned fear responses. Nevertheless, this approach is only partially resolutive, since many patients have difficulty following the demanding and long process, and relapses are frequently observed over time. One strategy to improve the efficacy of the cognitive therapy is the combination with pharmacological agents. Therefore, the identification of compounds able to strengthen the formation and persistence of the inhibitory associations is a key goal. Recently, growing interest has been aroused by the neuropeptide oxytocin (OXT), which has been shown to have anxiolytic effects. Furthermore, OXT receptors and binding sites have been found in the critical brain structures involved in fear extinction. In this review, the recent literature addressing the complex effects of OXT on fear extinction at preclinical and clinical levels is discussed. These studies suggest that the OXT roles in fear behavior are due to its local effects in several brain regions, most notably, distinct amygdaloid regions.


Assuntos
Medo/fisiologia , Ocitocina/metabolismo , Tonsila do Cerebelo/metabolismo , Tonsila do Cerebelo/fisiopatologia , Animais , Sítios de Ligação , Extinção Psicológica , Hipocampo/metabolismo , Hipocampo/fisiologia , Humanos , Masculino , Córtex Pré-Frontal/metabolismo , Córtex Pré-Frontal/fisiologia , Ratos Wistar , Receptores de Ocitocina/metabolismo , Receptores de Ocitocina/fisiologia
7.
Adv Exp Med Biol ; 1166: 75-85, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31301047

RESUMO

Spermatozoa have the task to deliver an intact paternal genome to the oocyte and to support a successful embryo development. The high levels of sperm DNA fragmentation (sDF) found in sub-/infertile men threat human reproduction and health of the offspring. Strategies to prevent the onset of this type of sperm damage are extensively sought.sDF can be induced by factors like lifestyle-related habits, diseases, drugs, aging, infections and exposure to pollutants. At the cell level, all these factors induce sperm DNA breaks by three main mechanisms: apoptosis, impairment of sperm chromatin maturation and oxidative stress. Apoptosis and defects in maturation of sperm chromatin appear to act in the testis and account for DNA breaks found in dead ejaculated spermatozoa, whereas oxidative stress is likely inducing sDF during the transit through the male genital tracts and accounting for DNA breaks observed in viable spermatozoa of the ejaculate. Oxidative stress appears to be also the main mechanism responsible for induction of sDF after ejaculation, during in vitro manipulation of spermatozoa. Whether or not mature spermatozoa are able to trigger a cell death program is not yet clarified. In particular, it is not clear whether apoptotic nucleases or reactive oxygen species are responsible for producing DNA breaks in ejaculated mature spermatozoa. Knowledge of the mechanisms inducing sDF is a valuable starting point to define possible therapeutic options that however are still far to be established.


Assuntos
Fragmentação do DNA , Espermatozoides , Humanos , Masculino , Maturação do Esperma , Espermatozoides/patologia , Testículo
8.
Proc Natl Acad Sci U S A ; 113(19): E2714-20, 2016 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-27118833

RESUMO

Retrieval represents a dynamic process that may require neuromodulatory signaling. Here, we report that the integrity of the brain histaminergic system is necessary for retrieval of inhibitory avoidance (IA) memory, because rats depleted of histamine through lateral ventricle injections of α-fluoromethylhistidine (a-FMHis), a suicide inhibitor of histidine decarboxylase, displayed impaired IA memory when tested 2 d after training. a-FMHis was administered 24 h after training, when IA memory trace was already formed. Infusion of histamine in hippocampal CA1 of brain histamine-depleted rats (hence, amnesic) 10 min before the retention test restored IA memory but was ineffective when given in the basolateral amygdala (BLA) or the ventral medial prefrontal cortex (vmPFC). Intra-CA1 injections of selective H1 and H2 receptor agonists showed that histamine exerted its effect by activating the H1 receptor. Noteworthy, the H1 receptor antagonist pyrilamine disrupted IA memory retrieval in rats, thus strongly supporting an active involvement of endogenous histamine; 90 min after the retention test, c-Fos-positive neurons were significantly fewer in the CA1s of a-FMHis-treated rats that displayed amnesia compared with in the control group. We also found reduced levels of phosphorylated cAMP-responsive element binding protein (pCREB) in the CA1s of a-FMHis-treated animals compared with in controls. Increases in pCREB levels are associated with retrieval of associated memories. Targeting the histaminergic system may modify the retrieval of emotional memory; hence, histaminergic ligands might reduce dysfunctional aversive memories and improve the efficacy of exposure psychotherapies.


Assuntos
Aprendizagem da Esquiva/fisiologia , Hipocampo/fisiologia , Histamina/metabolismo , Inibição Psicológica , Rememoração Mental/fisiologia , Receptores Histamínicos H1/metabolismo , Animais , Masculino , Neurotransmissores/metabolismo , Ratos , Ratos Wistar
9.
Proc Natl Acad Sci U S A ; 112(19): E2536-42, 2015 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-25918368

RESUMO

Recent discoveries demonstrated that recruitment of alternative brain circuits permits compensation of memory impairments following damage to brain regions specialized in integrating and/or storing specific memories, including both dorsal hippocampus and basolateral amygdala (BLA). Here, we first report that the integrity of the brain histaminergic system is necessary for long-term, but not for short-term memory of step-down inhibitory avoidance (IA). Second, we found that phosphorylation of cyclic adenosine monophosphate (cAMP) responsive-element-binding protein, a crucial mediator in long-term memory formation, correlated anatomically and temporally with histamine-induced memory retrieval, showing the active involvement of histamine function in CA1 and BLA in different phases of memory consolidation. Third, we found that exogenous application of histamine in either hippocampal CA1 or BLA of brain histamine-depleted rats, hence amnesic, restored long-term memory; however, the time frame of memory rescue was different for the two brain structures, short lived (immediately posttraining) for BLA, long lasting (up to 6 h) for the CA1. Moreover, long-term memory was formed immediately after training restoring of histamine transmission only in the BLA. These findings reveal the essential role of histaminergic neurotransmission to provide the brain with the plasticity necessary to ensure memorization of emotionally salient events, through recruitment of alternative circuits. Hence, our findings indicate that the histaminergic system comprises parallel, coordinated pathways that provide compensatory plasticity when one brain structure is compromised.


Assuntos
Aprendizagem da Esquiva , Complexo Nuclear Basolateral da Amígdala/metabolismo , Região CA1 Hipocampal/metabolismo , Histamina/metabolismo , Amnésia/metabolismo , Tonsila do Cerebelo/metabolismo , Animais , Encéfalo/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Emoções , Masculino , Memória de Longo Prazo , Microdiálise , Modelos Animais , Fosforilação , Ratos , Ratos Wistar , Transmissão Sináptica
10.
Int J Neuropsychopharmacol ; 20(5): 392-399, 2017 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-28339575

RESUMO

Background: The integrity of the brain histaminergic system is necessary for the unfolding of homeostatic and cognitive processes through the recruitment of alternative circuits with distinct temporal patterns. We recently demonstrated that the fat-sensing lipid mediator oleoylethanolamide indirectly activates histaminergic neurons to exerts its hypophagic effects. The present experiments investigated whether histaminergic neurotransmission is necessary also for the modulation of emotional memory induced by oleoylethanolamide in a contextual fear conditioning paradigm. Methods: We examined the acute effect of i.p. administration of oleoylethanolamide immediately posttraining in the contextual fear conditioning test. Retention test was performed 72 hours after training. To test the participation of the brain histaminergic system in the cognitive effect of oleoylethanolamide, we depleted rats of brain histamine with an i.c.v. injection of alpha-fluoromethylhistidine (a suicide inhibitor of histidine decarboxylase) or bilateral intra-amygdala infusions of histamine H1 or H2 receptor antagonists. We also examined the effect of oleoylethanolamide on histamine release in the amygdala using in vivo microdialysis. Results: Posttraining administration of oleoylethanolamide enhanced freezing time at retention. This effect was blocked by both i.c.v. infusions of alpha-fluoromethylhistidine or by intra-amygdala infusions of either pyrilamine or zolantidine (H1 and H2 receptor antagonists, respectively). Microdialysis experiments showed that oleoylethanolamide increased histamine release from the amygdala of freely moving rats. Conclusions: Our results suggest that activation of the histaminergic system in the amygdala has a "permissive" role on the memory-enhancing effects of oleoylethanolamide. Hence, targeting the H1 and H2 receptors may modify the expression of emotional memory and reduce dysfunctional aversive memories as found in phobias and posttraumatic stress disorder.


Assuntos
Cognição/efeitos dos fármacos , Condicionamento Psicológico/efeitos dos fármacos , Endocanabinoides/farmacologia , Medo/efeitos dos fármacos , Histamina/metabolismo , Ácidos Oleicos/farmacologia , Análise de Variância , Animais , Benzotiazóis/farmacologia , Inibidores Enzimáticos/farmacologia , Reação de Congelamento Cataléptica/efeitos dos fármacos , Histamínicos/farmacologia , Hipotálamo/efeitos dos fármacos , Masculino , Metilistidinas/farmacologia , Microdiálise , Fenoxipropanolaminas/farmacologia , Piperidinas/farmacologia , Ratos , Ratos Wistar
11.
Reprod Fertil Dev ; 29(4): 637-645, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26464079

RESUMO

Sperm cryopreservation is widely used by cancer patients undergoing chemo- or radiotherapy. Evidence suggests that IVF outcome with cryopreserved spermatozoa from cancer patients is less successful. To determine whether sperm DNA fragmentation (SDF) is involved in the lower fertilising ability of cryopreserved spermatozoa of cancer patients, SDF was evaluated in thawed spermatozoa from 78 men affected by different cancers and 53 men with non-cancer pathologies. SDF was assessed by the terminal deoxyribonucleotidyl transferase-mediated dUTP-digoxigenin nick end-labelling (TUNEL), propidium iodide (PI), flow cytometry procedure, which allows determination of two different cell populations (PIbrighter and PIdimmer) and thus to determine the percentage of DNA fragmented sperm in both. PIdimmer spermatozoa are totally unviable, whereas PIbrighter spermatozoa with SDF may be motile and morphologically normal, having higher biological relevance in the reproductive process. We found that the proportion of DNA fragmented PIbrighter cells was significantly higher in thawed spermatozoa from cancer than non-cancer patients. Moreover, a positive correlation was found between the degree of DNA fragmentation and sperm motility in the PIbrighter population of spermatozoa from cancer patients that wasn't seen in non-cancer patients. The results of the present study suggest that higher SDF levels may contribute to the lower IVF success of cryopreserved spermatozoa from cancer patients and that evaluation of SDF could complement genetic counselling as part of the routine management of cancer patients who seek fertility preservation.


Assuntos
Fragmentação do DNA , Neoplasias/patologia , Preservação do Sêmen , Espermatozoides/patologia , Criopreservação , Humanos , Masculino , Neoplasias/metabolismo , Análise do Sêmen , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/metabolismo
12.
Hum Reprod ; 31(9): 1960-9, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27329968

RESUMO

STUDY QUESTION: Does the sperm DNA fragmentation index (DFI) improve depending on the FSH receptor (FSHR) genotype as assessed by the nonsynonymous polymorphisms rs6166 (p.N680S) after 3 months of recombinant FSH treatment in men with idiopathic infertility? SUMMARY ANSWER: FSH treatment significantly improves sperm DFI only in idiopathic infertile men with the p.N680S homozygous N FSHR. WHAT IS KNOWN ALREADY: FSH, fundamental for spermatogenesis, is empirically used to treat male idiopathic infertility and several studies suggest that DFI could be a candidate predictor of response to FSH treatment, in terms of probability to conceive. Furthermore, it is known that the FSHR single nucleotide polymorphism (SNP) rs6166 (p.N680S) influences ovarian response in women and testicular volume in men. STUDY DESIGN, SIZE AND DURATION: A multicenter, longitudinal, prospective, open-label, two-arm clinical trial was performed. Subjects enrolled were idiopathic infertile men who received 150 IU recombinant human FSH s.c. every other day for 12 weeks and were followed-up for a further 12 weeks after FSH withdrawal. Patients were evaluated at baseline, at the end of treatment and at the end of follow-up. PARTICIPANTS/MATERIALS, SETTING, METHODS: Eighty-nine men with idiopathic infertility carrier of the FSHR p.N680S homozygous N or S genotype, FSH ≤ 8 IU/l and DFI >15%, were enrolled. A total of 66 patients had DFI analysis completed on at least two visits. DFI was evaluated in one laboratory by TUNEL/PI (propidium iodide) assay coupled to flow cytometry, resolving two different fractions of sperm, namely the 'brighter' and 'dimmer' sperm DFI fractions. MAIN RESULTS AND THE ROLE OF CHANCE: Thirty-eight men (57.6%) were carriers of the p.N680S homozygous N and 28 (42.4%) of the homozygous S FSHR. Sperm concentration/number was highly heterogeneous and both groups included men ranging from severe oligozoospermia to normozoospermia. Total DFI was significantly lower at the end of the study in homozygous carriers of the p.N680S N versus p.N680S S allele (P = 0.008). Total DFI decreased significantly from baseline to the end of the study (P = 0.021) only in carriers of the p.N680S homozygous N polymorphism, and this decrease involved the sperm population containing vital sperm (i.e. brighter sperm) (P = 0.008). The dimmer sperm DFI fraction, including only nonvital sperm, was significantly larger in p.N680S S homozygous patients than in homozygous N men (P = 0.018). Total DFI was inversely related to total sperm number (P = 0.020) and progressive sperm motility (P = 0.014). When patients were further stratified according to sperm concentration (normoozospermic versus oligozoospermic) or -211G>T polymorphism in the FSHB gene (rs10835638) (homozygous G versus others), the significant improvement of sperm DFI in FSHR p.N680S homozygous N men was independent of sperm concentration and associated with the homozygous FSHB -211G>T homozygous G genotype. LIMITATIONS, REASONS FOR CAUTION: The statistical power of the study is 86.9% with alpha error 0.05. This is the first pharmacogenetic study suggesting that FSH treatment induces a significant improvement of total DFI in men carriers of the p.N680S homozygous N FSHR; however, the results need to be confirmed in larger studies using a personalized FSH dosage and treatment duration. WIDER IMPLICATIONS OF THE FINDINGS: The evaluation of sperm DFI as a surrogate marker of sperm quality, and of the FSHR SNP rs6166 (p.N680S), might be useful to predict the response to FSH treatment in men with idiopathic infertility. STUDY FUNDING/COMPETING INTERESTS: The study was supported by an unrestricted grant to M.S. and H.M.B. from Merck Serono that provided the drug used in the study. MS received additional grants from Merck Serono and IBSA as well as honoraria from Merck Serono. The remaining authors declare that no conflicts of interest are present. TRIAL REGISTRATION NUMBER: EudraCT number 2010-020240-35.


Assuntos
Fragmentação do DNA/efeitos dos fármacos , Hormônio Foliculoestimulante Humano/farmacologia , Infertilidade Masculina/tratamento farmacológico , Polimorfismo de Nucleotídeo Único , Receptores do FSH/genética , Adulto , Alelos , Hormônio Foliculoestimulante Humano/uso terapêutico , Genótipo , Humanos , Infertilidade Masculina/genética , Masculino , Testes Farmacogenômicos , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatogênese/genética , Espermatozoides/efeitos dos fármacos , Resultado do Tratamento
14.
Mol Med ; 21: 109-22, 2015 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-25786204

RESUMO

Sperm DNA fragmentation (sDF) represents a threat to male fertility, human reproduction and the health of the offspring. The causes of sDF are still unclear, even if apoptosis, oxidative assault and defects in chromatin maturation are hypothesized. Using multicolor flow cytometry and sperm sorting, we challenged the three hypothesized mechanisms by simultaneously evaluating sDF and signs of oxidative damage (8-hydroxy, 2'-deoxyguanosine [8-OHdG] and malondialdehyde [MDA]), apoptosis (caspase activity and cleaved poly[ADP-ribose] polymerase [cPARP]) and sperm immaturity (creatine phosphokinase [CK] and excess of residual histones). Active caspases and c-PARP were concomitant with sDF in a high percentage of spermatozoa (82.6% ± 9.1% and 53.5% ± 16.4%, respectively). Excess of residual histones was significantly higher in DNA-fragmented sperm versus sperm without DNA fragmentation (74.8% ± 17.5% and 37.3% ± 16.6%, respectively, p < 0.005), and largely concomitant with active caspases. Conversely, oxidative damage was scarcely concomitant with sDF in the total sperm population, at variance with live sperm, where 8-OHdG and MDA were clearly associated to sDF. In addition, most live cells with active caspase also showed 8-OHdG, suggesting activation of apoptotic pathways in oxidative-injured live cells. This is the first investigation on the origin of sDF directly evaluating the simultaneous presence of the signs of the hypothesized mechanisms with DNA breaks at the single cell level. The results indicate that the main pathway leading to sperm DNA breaks is a process of apoptosis, likely triggered by an impairment of chromatin maturation in the testis and by oxidative stress during the transit in the male genital tract. These findings are highly relevant for clinical studies on the effects of drugs on sDF and oxidative stress in infertile men and for the development of new therapeutic strategies.


Assuntos
Fragmentação do DNA , Espermatozoides/metabolismo , 8-Hidroxi-2'-Desoxiguanosina , Apoptose , Caspases/metabolismo , Creatina Quinase/genética , Creatina Quinase/metabolismo , Dano ao DNA , Desoxiguanosina/análogos & derivados , Desoxiguanosina/metabolismo , Ativação Enzimática , Citometria de Fluxo , Expressão Gênica , Humanos , Masculino , Estresse Oxidativo
15.
Hum Reprod ; 29(3): 418-28, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24430778

RESUMO

STUDY QUESTION: Does CatSper have a role in the achievement of human sperm motility and in the Progesterone (P)-induced acrosome reaction (AR)? SUMMARY ANSWER: CatSper1 expression is associated with human sperm progressive motility and the P-induced AR; it may have a role in the pathogenesis of asthenozoospermia. WHAT IS KNOWN ALREADY: Knockout mice for any of the Catsper family genes fail to acquire hyperactivated motility and are infertile. CatSper channels mediate P-induced Ca(2+) influx in human sperm. The role of CatSper in human sperm hyperactivated/activated motility and in asthenospermia is less clear. A few men with CatSper mutations have been described but the phenotype regarding sperm motility has not been well established. STUDY DESIGN, SIZE, DURATION: The effects of two Catsper inhibitors, NNC55-0396 (NNC, 10 and 20 µM) and Mibefradil (Mib, 30 and 40 µM), were tested on human sperm motility parameters and the P-induced AR. Catsper1 protein expression was evaluated in unselected and swim-up selected sperm samples and in sperm from normo- and astheno-zoospermic subjects. PARTICIPANTS/MATERIALS, SETTING, METHODS: Semen sample kinematic parameters were analysed by a CASA system. A fluorescent-labelled lectin was used to evaluate P-induced AR in live sperm by fluorescence microscopy. CatSper1 protein expression was determined by western blot analysis and by flow cytometry. Intracellular calcium concentrations ([Ca(2+)]i) were evaluated by a spectrofluorimetric method following sperm loading with the calcium-sensitive probe fura 2/AM. MAIN RESULTS AND THE ROLE OF CHANCE: CatSper1 protein was localized in the tail of human sperm. CatSperI expression was higher in swim up selected than unselected sperm both when measured by western blot or by flow cytometry (52.7 ± 15.8% versus 27.2 ± 9.01%, n = 7, P < 0.01). Basal and P-stimulated [Ca(2+)]i were significantly higher in swim-up selected compared with unselected sperm. CatSper1 expression (western blot analysis) was found to be decreased in sperm from asthenozoospermic (n = 10) compared with those from normozoospermic (n = 9) men (intensity values relative to ß-actin: 244.4 ± 69.3 versus 385.8 ± 139.5, P < 0.01). A positive correlation was found between CatSper1 protein expression and the percentage of sperm with progressive motility (n = 19, r = 0.59, P = 0.007). NNC (10 µM) and Mib (30 µM) significantly reduced the percentage of sperm with progressive motility and several kinematic parameters but did not affect the percentage of hyperactivated sperm. Their effects were the same whether they were added to swim-up selected and capacitated sperm or were added to the swim-up medium. Mib was found to have a slight but significant effect on sperm viability at both concentrations tested. P-stimulated AR was significantly reduced by both inhibitors (P < 0.05). Overall, our results indicate that, in human sperm, CatSper channel expression and function are associated with progressive motility and may be involved in the pathogenesis of asthenozoospermia. LIMITATIONS, REASONS FOR CAUTION: In general, studies evaluating the effect of inhibitors have the limitation of the specificity of the molecules. We show here that Mib may have toxic effect on human sperm. Although most of the parameters have been evaluated in live sperm, the toxic effect could have contributed to the observed decreases. More studies are necessary to evaluate further the role of CatSper1 in asthenozoospermia. WIDER IMPLICATIONS OF THE FINDINGS: In view of the involvement in P-induced AR and of the evidence of a role in the pathogenesis of astenozoospermia, CatSper channels may represent a promising target for the development of new drugs for the treatment of male infertility and for non-hormonal contraception. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by grants from Ministry of University and Scientific Research (Prin project to E.B. and FIRB project to S.M) and Regione Toscana (to G.F.). The authors have no conflicts of interest to declare.


Assuntos
Reação Acrossômica/efeitos dos fármacos , Canais de Cálcio/fisiologia , Progesterona/farmacologia , Motilidade dos Espermatozoides/efeitos dos fármacos , Animais , Astenozoospermia/fisiopatologia , Bloqueadores dos Canais de Cálcio/farmacologia , Canais de Cálcio/biossíntese , Canais de Cálcio/efeitos dos fármacos , Humanos , Masculino , Mibefradil/farmacologia
16.
Neurobiol Learn Mem ; 110: 64-71, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24569052

RESUMO

During contextual fear conditioning a rat learns a temporal contiguity association between the exposition to a previously neutral context (CS) and an aversive unconditioned stimulus (US) as a footshock. This condition determines in the rat the freezing reaction during the subsequent re-exposition to the context. Potentially the re-exposition without US presentation initiates two opposing and competing processes: reconsolidation and extinction. Reconsolidation process re-stabilizes and strengthens the original memory and it is initiated by a brief re-exposure to context. Instead the extinction process leads to the decrease of the expression of the original memory and it is triggered by prolonged re-exposure to the context. Here we analyzed the entorhinal cortex (ENT) participation in contextual fear conditioning reconsolidation and extinction. The rats were trained in contextual fear conditioning and 24h later they were subjected either to a brief (2 min) reactivation session or to a prolonged (120 min) re-exposition to context to induce extinction of the contextual fear memory. Immediately after the reactivation or the extinction session, the animals were submitted to bilateral ENT TTX inactivation. Memory retention was assessed as conditioned freezing duration measured 72 h after TTX administration. The results showed that ENT inactivation both after reactivation and extinction session was followed by contextual freezing retention impairment. Thus, the present findings point out that ENT is involved in contextual fear memory reconsolidation and extinction. This neural structure might be part of parallel circuits underlying two phases of contextual fear memory processing.


Assuntos
Aprendizagem por Associação/fisiologia , Condicionamento Clássico/fisiologia , Córtex Entorrinal/fisiologia , Extinção Psicológica/fisiologia , Medo/fisiologia , Animais , Emoções/fisiologia , Reação de Congelamento Cataléptica/fisiologia , Masculino , Ratos , Ratos Wistar
17.
Andrology ; 12(4): 862-869, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37706229

RESUMO

BACKGROUND: Sperm cryopreservation is an important procedure for oligozoospermic subjects at risk of azoospermia and after surgical recovery of spermatozoa in non-obstructive azoospermic men. Conventional procedures for sperm cryopreservation might be, however, not suitable for samples with a very low sperm number. OBJECTIVES: In this pilot study, we investigated the recoveries of sperm motility and viability in severe oligozoospermic subjects (n = 39) after cryopreservation with a tip-microVapour Fast Freezing, a procedure previously developed by our group for men with good semen quality. Sperm DNA fragmentation was also evaluated in a second group of oligozoospermic samples (n = 16). MATERIALS AND METHODS: We used a Vapour Fast Freezing procedure using 10 µL tips as carrier, and Test Yolk Buffer as freezing medium (tip-microVapour Fast Freezing). In a subset of samples (n = 22), we compared recovery of motility and viability as obtained with tip-microVapour Fast Freezing and with a Vapour Fast Freezing procedure using 500 µL straws. Sperm DNA fragmentation was evaluated by the sperm chromatin dispersion test. RESULTS: We found a recovery rate (median [interquartile range]) of 0.29 (0.13-0.41) for progressive motility, 0.30 (0.21-0.52) for total motility and 0.48 (0.29-0.60) for viability. Interestingly, we observed that samples with the poorest motility were apparently less damaged by freezing/thawing. In a subset of samples (n = 22), we directly compared values of viability, progressive motility and total motility by freezing/thawing with tip-microVapour Fast Freezing and Vapour Fast Freezing conducted with 500 µL straws. We found much better values of all sperm parameters in samples after freezing/thawing with tip-microVapour Fast Freezing than with Vapour Fast Freezing in 500 µL straws: that is, progressive motility: 7.00 (3.00-8.50)% versus 2.00 (0.00-4.25)%, p < 0.001; total motility: 12.00 (8.00-16.25)% versus 6.50 (1.00-9.25)%, p < 0.001; viability: 29.75 (23.75-45.25) versus 22.50 (13.75-28.13), p < 0.001, respectively. In the second group of oligozoospermic samples, we found that tip-microVapour Fast Freezing produced lower levels of sperm DNA fragmentation than straws (33.00 [19.75-36.00]% vs. 36.00 [22.75-41.87]%, p < 0.001). DISCUSSION AND CONCLUSION: Tip-microVapour Fast Freezing appears to be a very promising method to cryopreserve semen samples from severe oligozoospermic patients.


Assuntos
Azoospermia , Oligospermia , Preservação do Sêmen , Humanos , Masculino , Congelamento , Análise do Sêmen , Sêmen , Projetos Piloto , Motilidade dos Espermatozoides , Criopreservação/métodos , Espermatozoides , Oligospermia/cirurgia , Preservação do Sêmen/métodos
18.
BMC Psychol ; 12(1): 340, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38858743

RESUMO

BACKGROUND: Sleep is vital for maintaining individuals' physical and mental health and is particularly challenged during pregnancy. More than 70% of women during the gestational period report insomnia symptoms. Sleep dysfunction in the peripartum increases the risk for a cascade of negative health outcomes during late pregnancy, birth, and postpartum. While psychological interventions are considered the first line treatment for sleep difficulties, they are still scarcely offered during pregnancy and there is a lack of longitudinal research combining psychological and physiological indices. METHODS: The present protocol outlines a randomized controlled trial aimed at testing the long-term effectiveness of an automatized digitalized psychoeducational intervention for insomnia for expectant mothers complaining insomnia symptoms without comorbidity. Outcomes include physiological, hormonal, and subjective indices of maternal psychopathology, stress, and emotional processes, and sleep and wellbeing of the family system. The trial is part of a longitudinal study evaluating expectant mothers from early pregnancy (within the 15th gestational week) to 6-months postpartum through 6 observational phases: baseline (BSL), 6- and 12-weeks from BSL (FU1-FU2), 2-to-4 weeks after delivery (FU3), and 3- and 6-months after delivery (FU4-5). We plan to recruit 38 women without sleep difficulties (Group A) and 76 women with sleep difficulties (Group B). Group B will be randomly assigned to digital psychological control intervention (B1) or experimental psychoeducational intervention targeting insomnia (B2). At 3 time points, an ecological-momentary-assessment (EMA) design will be used to collect data on sleep and emotions (diaries), sleep-wake parameters (actigraphy) and stress reactivity (salivary cortisol). We will also test the DNA methylation of genes involved in the stress response as biomarkers of prenatal poor sleep. Information on partner's insomnia symptoms and new-borns' sleep will be collected at each stage. DISCUSSION: The proposed protocol aims at testing an easily accessible evidence-based psychoeducational intervention for expectant mothers to help them improving sleep, health, and wellbeing in the peripartum. The results could improve the understanding and management of sleep difficulties and peripartum depression. TRIAL REGISTRATION: The study protocol has been registered on 22 April 2024 with ClinicalTrials.gov Protocol Registration and Results System (PRS), ID: NCT06379074. PROTOCOL VERSION: April 23, 2024.


Assuntos
Distúrbios do Início e da Manutenção do Sono , Humanos , Feminino , Gravidez , Distúrbios do Início e da Manutenção do Sono/terapia , Distúrbios do Início e da Manutenção do Sono/psicologia , Estudos Longitudinais , Adulto , Mães/psicologia , Complicações na Gravidez/terapia , Complicações na Gravidez/psicologia , Saúde da Mulher , Período Pós-Parto/psicologia
19.
Artigo em Inglês | MEDLINE | ID: mdl-38402304

RESUMO

BACKGROUND: Hyperglycemia can promote the development of prostate cancer (PCa). Differential expression levels of miRNAs between PCa patients and controls were also reported. Therefore, we examined the relationship between hyperglycemia and miRNA levels in PCa. METHODS: Relative expression of urinary miR-574-3p, miR-375, miR-205-5p, miR-200b-3p, miR-187-3p, miR-182-5p, and miR-100-5p were investigated in 105 PCa patients and 138 noncancer controls by Real-Time quantitative PCR. Fasting plasma glucose measurements were retrieved from clinical records. The differential miRNA expressions among groups were compared using non-parametric tests. Correlations with glucose and prostate-specific antigen (PSA) were tested using Pearson correlation coefficient. RESULTS: When we analyzed miRNA expression according to glycemic state, significant down-regulations were found for miR-200b-3p, miR-187-3p, miR-182-5p, and miR-100-5p in noncancer controls with high glucose. The lowest down-regulations were observed for miR-187-3p, miR-182-5p, and miR-100-5p. Subsequently, when hyperglycemia was considered in PCa, significant dysregulations of selected miRNAs were found in hyperglycemic PCa patients than in controls with high glucose. In particular, miR-375 and miR-182-5p showed a 3-FC in hyperglycemic PCa patients than controls who left hyperglycemia untreated. Conversely, only a down-regulation of miR-574-3p was observed in PCa patients regardless of glycemic status and only modest down-regulation of miR-574-3p, miR-200b-3p, miR-187-3p and miR-182-5p were found in normoglycemic PCa patients. Next, significant correlations between miRNAs and glucose (miR-200b-3p, miR-100-5p) and PSA (miR-205-5p and miR-187-3p) were detected in controls. Similarly, miR-205-5p and miR-187-3p were correlated with glucose in PCa patients, while miR-574-3p and miR-375 showed inverse relationships. CONCLUSIONS: miRNA dysregulations can occur in hyperglycemic PCa patients as compared to noncancer controls who left hyperglycemia untreated. Hyperglycemia can consistently promote the expression of miR-375 and miR-182-5p. Uncontrolled hyperglycemic state could contribute to the creation of a suitable microenvironment for later PCa development by promoting gene expression.

20.
Int J Neuropsychopharmacol ; 16(3): 575-82, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22418001

RESUMO

The role of the nucleus basalis magnocellularis (NBM) in fear conditioning encoding is well established. In the present report, we investigate the involvement of the NBM histaminergic system in consolidating fear memories. The NBM was injected bilaterally with ligands of histaminergic receptors immediately after contextual fear conditioning. Histaminergic compounds, either alone or in combination, were stereotaxically administered to different groups of adult male Wistar rats and memory was assessed as conditioned freezing duration 72 h after administration. This protocol prevents interference with NBM function during either acquisition or retrieval phases, hence restricting the effect of pharmacological manipulations to fear memory consolidation. The results presented here demonstrate that post-training H3 receptors (H3R) blockade with the antagonist/inverse agonist thioperamide or activation with immepip in the NBM potentiates or decreases, respectively, freezing response at retrieval. Thioperamide induced memory enhancement seems to depend on H2R, but not H1R activation, as the H2R antagonist zolantidine blocked the effect of thioperamide, whereas the H1R antagonist pyrilamine was ineffective. Furthermore, the H2R agonist ampthamine improved fear memory expression independently of the H3R agonist effect. Our results indicate that activation of post-synaptic H2R within the NBM by endogenous histamine is responsible for the potentiated expression of fear responses. The results are discussed in terms of activation of H3 auto- and heteroreceptors within the NBM and the differential effect of H3R ligands on fear memory consolidation in distinct brain regions.


Assuntos
Núcleo Basal de Meynert/metabolismo , Condicionamento Psicológico/fisiologia , Medo/fisiologia , Agonistas dos Receptores Histamínicos/metabolismo , Antagonistas dos Receptores Histamínicos/metabolismo , Receptores Histamínicos H3/metabolismo , Animais , Núcleo Basal de Meynert/efeitos dos fármacos , Condicionamento Psicológico/efeitos dos fármacos , Medo/efeitos dos fármacos , Agonistas dos Receptores Histamínicos/administração & dosagem , Antagonistas dos Receptores Histamínicos/administração & dosagem , Injeções Intraventriculares , Ligantes , Masculino , Ratos , Ratos Wistar
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