RESUMO
BACKGROUND: Research on the possible influence of lateralised basal ganglia dysfunction on speech in Parkinson's disease is scarce. This study aimed to compare speech in de-novo, drug-naive patients with Parkinson's disease (PD) with asymmetric nigral dopaminergic dysfunction, predominantly in either the right or left hemisphere. METHODS: Acoustic analyses of reading passages were performed. Asymmetry of nigral dysfunction was defined using dopamine transporter-single-photon emission CT (DAT-SPECT). RESULTS: From a total of 135 de novo patients with PD assessed, 47 patients had a lower right and 36 lower left DAT availability in putamen based on DAT-SPECT. Patients with PD with lower left DAT availability had higher dysarthria severity via composite dysarthria index compared with patients with lower right DAT availability (p=0.01). CONCLUSION: Our data support the crucial role of DAT availability in the left putamen in speech. This finding might provide important clues for managing speech following deep brain stimulation.
RESUMO
Salmonella spp. is among the most central etiological agents in foodborne bacterial disorders. To identify Salmonella spp., numerous new molecular techniques have been developed conversely to the traditional culture-based methods. In this work, a new peptide nucleic acid fluorescence in situ hybridization (PNA-FISH) method was developed for the specific detection of Salmonella species, allowing a faster analysis compared with the traditional methods (ISO 6579-1: 2017). The method was optimized based on a novel PNA probe (SalPNA1692) combined with a blocker probe to detect Salmonella in food samples through an assessment of diverse-rich and selective enrichment broths. Our findings indicated that the best outcome was obtained using a 24-h pre-enrichment step in buffered peptone water, followed by RambaQuick broth selective enrichment for 16 h. For the enrichment step performance validation, fresh ground beef was artificially contaminated with two ranges of concentration of inoculum: a low level (0.2-2 colony-forming units [CFUs]/25 g) and a high level (2-10 CFUs/25 g). The new PNA-FISH method presented a specificity of 100% and a detection limit of 0.5 CFU/25 g of food sample, which confirms the great potential of applying PNA probes in food analysis.
Assuntos
Microbiologia de Alimentos , Hibridização in Situ Fluorescente , Ácidos Nucleicos Peptídicos , Salmonella , Hibridização in Situ Fluorescente/métodos , Salmonella/isolamento & purificação , Salmonella/genética , Microbiologia de Alimentos/métodos , Animais , Contaminação de Alimentos/análise , Bovinos , Sensibilidade e Especificidade , Limite de Detecção , Carne Vermelha/microbiologiaRESUMO
BACKGROUND: The landscape of neurophysiological symptoms and behavioral biomarkers in basal ganglia signals for movement disorders is expanding. The clinical translation of sensing-based deep brain stimulation (DBS) also requires a thorough understanding of the anatomical organization of spectral biomarkers within the subthalamic nucleus (STN). OBJECTIVES: The aims were to systematically investigate the spectral topography, including a wide range of sub-bands in STN local field potentials (LFP) of Parkinson's disease (PD) patients, and to evaluate its predictive performance for clinical response to DBS. METHODS: STN-LFPs were recorded from 70 PD patients (130 hemispheres) awake and at rest using multicontact DBS electrodes. A comprehensive spatial characterization, including hot spot localization and focality estimation, was performed for multiple sub-bands (delta, theta, alpha, low-beta, high-beta, low-gamma, high-gamma, and fast-gamma (FG) as well as low- and fast high-frequency oscillations [HFO]) and compared to the clinical hot spot for rigidity response to DBS. A spectral biomarker map was established and used to predict the clinical response to DBS. RESULTS: The STN shows a heterogeneous topographic distribution of different spectral biomarkers, with the strongest segregation in the inferior-superior axis. Relative to the superiorly localized beta hot spot, HFOs (FG, slow HFO) were localized up to 2 mm more inferiorly. Beta oscillations are spatially more spread compared to other sub-bands. Both the spatial proximity of contacts to the beta hot spot and the distance to higher-frequency hot spots were predictive for the best rigidity response to DBS. CONCLUSIONS: The spatial segregation and properties of spectral biomarkers within the DBS target structure can additionally be informative for the implementation of next-generation sensing-based DBS. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.
Assuntos
Estimulação Encefálica Profunda , Doença de Parkinson , Núcleo Subtalâmico , Humanos , Gânglios da Base , Doença de Parkinson/terapia , EletrodosRESUMO
Parkinson's disease(PD) lacks a biomarker for disease progression. To analyze how cerebrospinal fluid (CSF), glucosylceramide (GlcCer), sphingomyelin (SM), or serum neurofilament light chain (NfL) associate with progression of PD in a retrospective cohort, we used linear mixed-model regressions between baseline biomarkers and change in dopamine transporter brain-imaging (DaTscan©), Montreal cognitive assesment (MoCA), or global composite outcome (GCO) score. In 191 PD patients, biomarkers were not associated with DaTscan or MoCA change over 2.1 years. Higher baseline GlcCer/SM ratio and serum-NfL nonsignificantly associated with increase in GCO score. Results do not support a role for CSF-sphingolipid/serum-NfL to predict cognitive and DaTscan progression in early-PD. Potential prediction of global clinical change warrants further study.
RESUMO
Here we report a quantitative analysis of human metaphase II (MII) oocytes from a 22-year-old oocyte donor, retrieved after ovarian-controlled hyperstimulation. Five surplus donor oocytes were processed for transmission electron microscopy (TEM), and a stereological analysis was used to quantify the distribution of organelles, using the point-counting technique with an adequate stereological grid. Comparisons between means of the relative volumes (Vv) occupied by organelles in the three oocyte regions, cortex (C), subcortex (SC) and inner cytoplasm (IC), followed the Kruskal-Wallis test and Mann-Whitney U-test with Bonferroni correction. Life cell imaging and TEM analysis confirmed donor oocyte nuclear maturity. Results showed that the most abundant organelles were smooth endoplasmic reticulum (SER) elements (26.8%) and mitochondria (5.49%). Significant differences between oocyte regions were found for lysosomes (P = 0.003), cortical vesicles (P = 0.002) and large SER vesicles (P = 0.009). These results were quantitatively compared with previous results using prophase I (GV) and metaphase I (MI) immature oocytes. In donor MII oocytes there was a normal presence of cortical vesicles, SER tubules, SER small, medium and large vesicles, lysosomes and mitochondria. However, donor MII oocytes displayed signs of cytoplasmic immaturity, namely the presence of dictyosomes, present in GV oocytes and rare in MI oocytes, of SER very large vesicles, characteristic of GV oocytes, and the rarity of SER tubular aggregates. Results therefore indicate that the criterion of nuclear maturity used for donor oocyte selection does not always correspond to cytoplasmic maturity, which can partially explain implantation failures with the use of donor oocytes.
Assuntos
Mitocôndrias , Oócitos , Humanos , Adulto Jovem , Adulto , Oócitos/metabolismo , Citoplasma , Oogênese , Núcleo CelularRESUMO
PURPOSE: The main objective of this opinion paper was to bring to light and enhance our understanding of the amount of double-strand DNA breaks in sperm and whether there is a threshold of no return when considering repair by the oocyte/embryo. METHODS: A brief review of literature related to the theories proposed for the appearance of double-strand breaks in human spermatozoa. Further commentary regarding their detection, how oocytes or embryos may deal with them, and what are the consequences if they are not repaired. Finally, a strategy for dealing with patients who have higher levels of double-strand DNA breaks in sperm is proposed by reviewing and presenting data using testicular extracted sperm. RESULTS: We propose a theory that a threshold may exist in the oocyte that allows either complete or partial DNA repair of impaired sperm. The closer that an embryo is exposed to the threshold, the more the effect on the ensuing embryo will fail to reach various milestones, including blastocyst stage, implantation, pregnancy loss, an adverse delivery outcome, or offspring health. We also present a summary of the role that testicular sperm extraction may play in improving outcomes for couples in which the male has a high double-strand DNA break level in his sperm. CONCLUSIONS: Double-strand DNA breaks in sperm provide a greater stress on repair mechanisms and challenge the threshold of repair in oocytes. It is therefore imperative that we improve our understanding and diagnostic ability of sperm DNA, and in particular, how double-strand DNA breaks originate and how an oocyte or embryo is able to deal with them.
Assuntos
Quebras de DNA de Cadeia Dupla , Sêmen , Gravidez , Feminino , Humanos , Masculino , Espermatozoides , Reparo do DNA/genética , Implantação do Embrião/genéticaRESUMO
INTRODUCTION: Cancer-associated-cachexia represents a systemic syndrome of unintended weight-loss (WL) and systemic inflammation, affecting >80% patients with pancreatic adenocarcinoma (PA). We aimed to evaluate the association of weight change (WC) with survival of patients treated with chemotherapy (ChT) for PA and the influence of disease staging. We also studied the prognostic and predictive value of inflammation-based scores. METHODS: Observational, retrospective cohort study. Individuals were divided into two cohorts, according to WC (WL ≥5% vs. non-WL <5%) after ChT. Main endpoints were weight change and survival time. Statistical analysis was performed using Stata software. RESULTS: Sixty-five patients were included (median age 69; 48% female), 60% with advanced disease. At 3 months after ChT start, 54% experienced WL. Advanced disease independently predicted WL (OR 2.10; 95% CI, 1.11-19.6; p = 0.041). With median follow-up of 14.8 mo, median survival time of patients with WL was 18.5 mo, vs. 33.2 vs. for non-WL (HR 2.28; 95% CI, 1.15-4.52; p = 0.019). In patients with early-stage disease, WL was associated with decreased survival time (21.9 vs. 67.6 mo; HR 23.68; 95% CI 2.39-234.75; p = 0.007), while the association of WL on survival time in advanced disease was not significant (HR 0.74; 95% CI, 0.34-1.60; p = 0.449). The multivariate survival model showed that WL (HR 1.11, 95% CI 1.03-1.20, p = 0.005) and cachexia (HR 3.76, 95% CI 1.07-13-18), p = 0.041) were associated with survival time, as well as location in body or tail (HR 3.05; 95% CI, 1.75-5.31; p < 0.001) and high Neutrophil-to-lymphocyte ratio (NLR) at 3 months (HR 6.20; 95% CI, 2.59-14.87; p < 0.001). CONCLUSION: WL was an independent prognostic factor for survival. Particularly in early stage disease, interventions targeting this modifiable factor may translate into better outcomes for PA patients. NLR may be a surrogate marker of systemic inflammatory status in this setting.
Assuntos
Adenocarcinoma , Neoplasias Pancreáticas , Redução de Peso , Adenocarcinoma/complicações , Adenocarcinoma/tratamento farmacológico , Idoso , Biomarcadores , Feminino , Humanos , Inflamação , Linfócitos , Masculino , Estadiamento de Neoplasias , Neutrófilos , Neoplasias Pancreáticas/complicações , Neoplasias Pancreáticas/tratamento farmacológico , Prognóstico , Estudos RetrospectivosRESUMO
BACKGROUND: Embryo selection in Familial amyloid polyneuropathy eradicates the disease, but the widespread application of preimplantation genetic testing (PGT) for this monogenic disease still requires greater political and clinical commitment. MAIN BODY: Familial amyloid polyneuropathy is a fatal, chronic, hereditary autosomal dominant neurodegenerative disorder caused by a single nucleotide mutation in the transthyretin gene. The disease courses with infertility, cachexia, blindness, renal failure, cardiovascular collapse, and premature death. Treatments include organ transplantation, transthyretin stabilizers, silencers and gene editing. Unfortunately, these treatments only improve the patient's quality of life. SHORT CONCLUSION: The application of PGT would prevent the disease, the birth of children with this devastating disease and the enormous health costs associated. For PGT to become the first reproductive option for patients, a paradigm shift in governmental, social and medical policies is necessary.
Assuntos
Neuropatias Amiloides Familiares , Criança , Humanos , Neuropatias Amiloides Familiares/diagnóstico , Neuropatias Amiloides Familiares/genética , Neuropatias Amiloides Familiares/terapia , Pré-Albumina/genética , Qualidade de Vida , Testes GenéticosRESUMO
While in most patients the identification of genetic alterations causing dystrophinopathies is a relatively straightforward task, a significant number require genomic and transcriptomic approaches that go beyond a routine diagnostic set-up. In this work, we present a Becker Muscular Dystrophy patient with elevated creatinine kinase levels, progressive muscle weakness, mild intellectual disability and a muscle biopsy showing dystrophic features and irregular dystrophin labelling. Routine molecular techniques (Southern-blot analysis, multiplex PCR, MLPA and genomic DNA sequencing) failed to detect a defect in the DMD gene. Muscle DMD transcript analysis (RT-PCR and cDNA-MLPA) showed the absence of exons 75 to 79, seen to be present at the genomic level. These results prompted the application of low-coverage linked-read whole-genome sequencing (WGS), revealing a possible rearrangement involving DMD intron 74 and a region located upstream of the PRDX4 gene. Breakpoint PCR and Sanger sequencing confirmed the presence of a ~8 Mb genomic inversion. Aberrant DMD transcripts were subsequently identified, some of which contained segments from the region upstream of PRDX4. Besides expanding the mutational spectrum of the disorder, this study reinforces the importance of transcript analysis in the diagnosis of dystrophinopathies and shows how WGS has a legitimate role in clinical laboratory genetics.
Assuntos
Distrofina/genética , Genoma/genética , Distrofia Muscular de Duchenne/diagnóstico , Distrofia Muscular de Duchenne/genética , Adulto , Sequência de Bases , Éxons/genética , Genética , Humanos , Masculino , Sequenciamento Completo do Genoma/métodos , Adulto JovemRESUMO
BACKGROUND: Breast cancer (BC) is a major health concern and better understanding of its biology might improve treatment decisions and patient outcomes. Histone3 Lysine27 tri-methylation (H3K27me3) is a post-translational histone modification frequently associated with altered gene expression. In BC patients, lower H3K27me3 expression has been associated with worse prognosis. We assessed H3K27me3 immunoexpression with digital imaging software assistance, in a cohort of luminal-like BC patients with long-term follow-up time and evaluated its association with clinically relevant endpoints and its clinical usefulness. METHODS: H3K27me3 immunoexpression was assessed, by means of digital-imaging system, in archival tissue samples of 160 luminal A/B-like HER2-negative invasive BC, stages I-III. Survival analysis was performed using Kaplan-Meier and Cox regression. Cases were categorized as 'low' or 'high' expression based on cut-off defined by receiver operating characteristic (ROC) curve analysis. RESULTS: The patient cohort showed a median age of 61-years, with a median follow-up time of 11.7 years. Low H3K27me3 expression (below 85% cut-off) was significantly associated with recurrence, both in univariable (HR = 1.99, 95%CI 1.066-3.724) and multivariable analysis when adjusting for grade and age (HR = 1.89, 95%CI 1.004-3.559). A trend for higher risk of death in low H3K27me3 expression BC was observed (p = 0.069), reaching statistical significance in younger patients (p = 0.021). CONCLUSIONS: H3K27me3 immunoexpression assessed by digital imaging scoring software is an independent prognosis biomarker in luminal-like BC patients and may assist in more individualized adjuvant treatment decisions, thus potentially reducing recurrences after curative-intent treatment, while sparing unnecessary toxicity.
Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/patologia , Regulação para Baixo , Histonas/metabolismo , Interpretação de Imagem Assistida por Computador/métodos , Neoplasias da Mama/metabolismo , Neoplasias da Mama/mortalidade , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Metilação , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Medicina de Precisão , Prognóstico , SoftwareRESUMO
RESEARCH QUESTION: A previous study showed that N-acetylcysteine (NAC), used after in-vitro exposure to the gonadotoxic chemotherapeutic drug etoposide, has the ability to decrease DNA damage in human spermatozoa; however, it showed no benefit when used before exposure. This study aimed to evaluate the impact of the NAC on the preservation of sperm quality during in-vitro exposure to etoposide. DESIGN: Twenty semen samples were submitted to four experimental conditions: control, NAC-only incubation, etoposide-only incubation, and concomitant etoposide and NAC incubation. After in-vitro incubation, semen parameters, sperm chromatin condensation, sperm DNA fragmentation, sperm oxidative stress and sperm metabolism were used to evaluate the role of NAC in protecting human spermatozoa from etoposide. RESULTS: Etoposide did not affect semen parameters, nor did it cause sperm oxidative damage or alterations in glycolytic profile. However, it induced chromatin decondensation and DNA fragmentation, which were fully prevented by NAC. CONCLUSIONS: NAC was able to protect sperm DNA integrity during etoposide treatment in vitro, suggesting that NAC may be useful as an adjuvant agent in preserving male fertility during chemotherapy treatments.
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/farmacologia , Dano ao DNA/efeitos dos fármacos , DNA , Etoposídeo/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Fragmentação do DNA/efeitos dos fármacos , Humanos , Masculino , Análise do Sêmen , Preservação do SêmenRESUMO
In the male reproductive tract, ionic equilibrium is essential to maintain normal spermatozoa production and, hence, the reproductive potential. Among the several ions, HCO3- and H+ have a central role, mainly due to their role on pH homeostasis. In the male reproductive tract, the major players in pH regulation and homeodynamics are carbonic anhydrases (CAs), HCO3- membrane transporters (solute carrier 4-SLC4 and solute carrier 26-SLC26 family transporters), Na+-H+ exchangers (NHEs), monocarboxylate transporters (MCTs) and voltage-gated proton channels (Hv1). CAs and these membrane transporters are widely distributed throughout the male reproductive tract, where they play essential roles in the ionic balance of tubular fluids. CAs are the enzymes responsible for the production of HCO3- which is then transported by membrane transporters to ensure the maturation, storage, and capacitation of the spermatozoa. The transport of H+ is carried out by NHEs, Hv1, and MCTs and is essential for the electrochemical balance and for the maintenance of the pH within the physiological limits along the male reproductive tract. Alterations in HCO3- production and transport of ions have been associated with some male reproductive dysfunctions. Herein, we present an up-to-date review on the distribution and role of the main intervenient on pH homeodynamics in the fluids throughout the male reproductive tract. In addition, we discuss their relevance for the establishment of the male reproductive potential.
Assuntos
Genitália Masculina/metabolismo , Concentração de Íons de Hidrogênio , Animais , Bicarbonatos/metabolismo , Anidrases Carbônicas/metabolismo , Fertilidade , Genitália Masculina/química , Homeostase , Humanos , Canais Iônicos/metabolismo , Bombas de Íon/metabolismo , Masculino , Transportadores de Ácidos Monocarboxílicos/metabolismo , Trocadores de Sódio-Hidrogênio/metabolismoRESUMO
BACKGROUND: Seminoma accounts for 30-50% of testicular germ cell tumors (TGCT)-the most common solid malignancy in men aged 15-35 years. The American Joint Committee on Cancer (AJCC) 8th edition (2018) created the subclassifications pT1a (tumor size < 3 cm) and pT1b (≥ 3 cm), despite not being universally recognized. Rete testis invasion (RTI) and tumor size > 4 cm are considered features associated with a higher recurrence risk, but not formally used for staging. The authors propose further understanding the subclassification's potential impact in clinical practice, by summarizing current evidence and reviewing clinical cases in their institutions. METHODS: All consecutive cases of seminoma stage I, pT1 treated in two institutions between January 2005 and December 2016 were included. Clinical data were retrieved, and variables were analyzed using SPSS. Relevant literature on the topic was reviewed. RESULTS: Seminoma pT1 was identified in 58 patients. By using newly AJCC criteria, 29 (50%) would have been staged as pT1a and 29 (50%) pT1b. Median age at diagnosis was similar (33 in pT1a vs 32 in pT1b). Median follow-up time 5.8 years. Almost half (45%) of pT1b patients had a tumor size < 4 cm. The majority of either pT1a or pT1b were treated with chemotherapy or radiotherapy, reflecting more intensive approaches in the past. Three retroperitoneal recurrences were recorded (two in pT1a, one in pT1b, all under surveillance protocol); no deaths occurred. RTI and extensive necrosis (EN) were associated with pT1b (P < 0.0001 and P = 0.023, respectively), known adverse biological features. CONCLUSIONS: In our population, the exploratory analysis of the newly created AJCC criteria showed no significant difference in recurrence or death, although pT1b was associated with adverse biomarkers, such as RTI and EN, but its clinical relevance remains incompletely understood. Our results confirm an excellent prognosis, regardless of subcategorization, thus a larger population and a longer follow-up time are needed to understand prospectively the impact of the recently updated criteria. We would recommend using the latest AJCC staging system, although the individual risk of relapse, long-term toxicities and patient preferences should be taken into account when considering surveillance or active treatment adjuvant options.
Assuntos
Seminoma/classificação , Seminoma/patologia , Neoplasias Testiculares/classificação , Neoplasias Testiculares/patologia , Adolescente , Adulto , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Retrospectivos , Estados Unidos , Adulto JovemRESUMO
We have previously presented a stereological analysis of organelle distribution in human prophase I oocytes. In the present study, using a similar stereological approach, we quantified the distribution of organelles in human metaphase I (MI) oocytes also retrieved after ovarian stimulation. Five MI oocytes were processed for transmission electron microscopy and a classical manual stereological technique based on point-counting with an adequate stereological grid was used. Kruskal-Wallis and Mann-Whitney U-tests with Bonferroni correction were used to compare the means of relative volumes (Vv) occupied by organelles. In all oocyte regions, the most abundant organelles were mitochondria and smooth endoplasmic reticulum (SER) elements. No significant differences were observed in Vv of mitochondria, dictyosomes, lysosomes, or SER small and medium vesicles, tubular aggregates and tubules. Significant differences were observed in other organelle distributions: cortical vesicles presented a higher Vv (P = 0.004) in the cortex than in the subcortex (0.96% vs 0.1%) or inner cytoplasm (0.96% vs 0.1%), vesicles with dense granular contents had a higher Vv (P = 0.005) in the cortex than in the subcortex (0.1% vs 0%), and SER large vesicles exhibited a higher Vv (P = 0.011) in the inner cytoplasm than in the subcortex (0.2% vs 0%). Future stereological analysis of metaphase II oocytes and a combined quantitative data of mature and immature oocytes, will enable a better understanding of oocyte organelle distribution during in vivo maturation. Combined with molecular approaches, this may help improve stimulation protocols and in vitro maturation methods.
Assuntos
Técnicas Citológicas/métodos , Metáfase , Oócitos/citologia , Retículo Endoplasmático Liso , Feminino , Humanos , Microscopia Eletrônica de Transmissão , Mitocôndrias , Oócitos/ultraestrutura , Organelas , Indução da Ovulação , FotografaçãoRESUMO
BACKGROUND: Strong evidence has suggested an important role of telomeres in meiosis, fertilization, and embryo development. PURPOSE: To determine if sperm telomere length (STL) in sperm purified by differential gradient centrifugation followed by swim-up (selected STL) is correlated with sperm quality and clinical outcomes. METHODS: Relative selected STL was assessed by quantitative polymerase chain reaction (Q-PCR) in 78 consecutive assisted reproductive technology (ART) treatments during 2017. Statistical analyses were performed in the totality of patients, and in normozoospermic and non-normozoospermic patients. These included correlations between selected STL and sperm quality parameters, embryological parameters (multivariable linear regression), and clinical parameters (multivariable logistic regression). RESULTS: No significant correlations were found between selected STL and sperm quality in the total population. However, selected STL was significantly correlated with total sperm count (r = 0.361; P = 0.039) and sperm DNA fragmentation-post-acrosomal region pattern (r = - 0.464; P = 0.030) in normozoospermic patients. No relation was observed between selected STL and clinical outcomes in any clinical group. CONCLUSIONS: As the correlations observed in normozoospermic patients were not representative of the whole heterogeneous population, differences in the sperm characteristics of the study population may lead to discrepant results when evaluating the association of STL with sperm quality. Since the total population selected STL was not related with sperm quality and with clinical outcomes, results do not support the use of selected STL measurement to evaluate the reproductive potential of the male patient or to predict the success rates of ART treatments.
Assuntos
Técnicas de Reprodução Assistida , Espermatozoides/citologia , Homeostase do Telômero/genética , Telômero/genética , Adulto , Centrifugação com Gradiente de Concentração , Humanos , Masculino , Pessoa de Meia-Idade , Contagem de Espermatozoides , Motilidade dos Espermatozoides/genética , Espermatozoides/crescimento & desenvolvimentoRESUMO
Mammalian target of rapamycin (mTOR) is a central regulator of cellular metabolic phenotype and is involved in virtually all aspects of cellular function. It integrates not only nutrient and energy-sensing pathways but also actin cytoskeleton organization, in response to environmental cues including growth factors and cellular energy levels. These events are pivotal for spermatogenesis and determine the reproductive potential of males. Yet, the molecular mechanisms by which mTOR signaling acts in male reproductive system remain a matter of debate. Here, we review the current knowledge on physiological and molecular events mediated by mTOR in testis and testicular cells. In recent years, mTOR inhibition has been explored as a prime strategy to develop novel therapeutic approaches to treat cancer, cardiovascular disease, autoimmunity, and metabolic disorders. However, the physiological consequences of mTOR dysregulation and inhibition to male reproductive potential are still not fully understood. Compelling evidence suggests that mTOR is an arising regulator of male fertility and better understanding of this atypical protein kinase coordinated action in testis will provide insightful information concerning its biological significance in other tissues/organs. We also discuss why a new generation of mTOR inhibitors aiming to be used in clinical practice may also need to include an integrative view on the effects in male reproductive system.
Assuntos
Fertilidade/fisiologia , Transdução de Sinais/fisiologia , Espermatogênese/fisiologia , Serina-Treonina Quinases TOR/metabolismo , Testículo/enzimologia , Animais , Humanos , MasculinoRESUMO
Sperm telomere length (STL) is a promising new parameter for sperm quality analysis that may elucidate the molecular mechanisms underlying the idiopathic cases of male factor infertility, which represent almost half of all the male factor infertility cases worldwide. Telomeres consist of nucleoprotein structures present at the ends of eukaryotic chromosomes, whose protective functions maintain the genomic stability. Their role in reproduction includes an active intervention during gametogenesis, fertilization, and preimplantation embryo development. In consonance, studies have shown that compromised telomere homeostasis is associated with male infertility. Since critically short telomeres have their function affected, assessing STL may be a fast and economic method for sperm quality analysis and expectantly contribute to improve the success of fertility treatments. This hypothesis is supported by several reports associating STL with seminal parameters, sperm genome integrity, and clinical outcomes. However, there are other studies in the literature that do not demonstrate these associations. Additionally, it is still not clear whether the lengthening mechanisms of telomeres occurring during early embryo development resume the inherited telomere length. Further research is essential to clarify the suitability of STL as a biomarker for male infertility, before it could be routinely implemented in medically assisted reproduction centers. Understanding the molecular mechanisms underlying STL function and dynamics will provide us new insights into the origins of male infertility and a possible new useful tool as an outcome predictor for assisted reproduction.
Assuntos
Infertilidade Masculina/genética , Telômero , Regulação da Expressão Gênica , Humanos , Masculino , Espermatozoides/fisiologiaRESUMO
Obesity incidence has pandemic proportions and is expected to increase even further. Glucagon-like peptide-1 (GLP-1) based therapies are well-established pharmacological resources for obesity treatment. GLP-1 regulates energy and glucose homeostasis, which are also crucial for spermatogenesis. Herein, we studied the GLP-1 effects in human Sertoli cells (hSCs) metabolism and mitochondrial function. hSCs were cultured in absence or exposed to increasing doses of GLP-1 mimicking physiological post-prandial (0.01â¯nM) levels or equivalent to pharmacological levels (1 and 100â¯nM) used for obesity treatment. We identified GLP-1 receptor in hSCs. Consumption/production of extracellular metabolites were assessed, as well as protein levels or activities of glycolysis-related enzymes and transporters. Mitochondrial membrane potential and oxidative damage were evaluated. Glucose consumption decreased, while lactate production increased in hSCs exposed to 0.01 and 1â¯nM GLP-1. Though lactate dehydrogenase (LDH) protein decreased after exposure to 100â¯nM GLP-1 its activity increased in hSCs exposed to the same concentration of GLP-1. Mitochondrial membrane potential decreased in hSCs exposed to 100â¯nM of GLP-1, while formation of carbonyl groups was decreased in those cells. Those effects were followed by an increase in p-mammalian target of rapamycin (mTOR) Ser(2448). Overall, the lowest concentrations of GLP-1 increased the efficiency of glucose conversion to lactate, while GLP-1 concentration of 100â¯nM induces mTOR phosphorylation, decreases mitochondrial membrane potential and oxidative damage. GLP-1 regulates testicular energy homeostasis and pharmacological use of GLP-1 analogues could be valuable to counteract the negative impact of obesity in male reproductive function.
Assuntos
Peptídeo 1 Semelhante ao Glucagon/farmacologia , Células de Sertoli/efeitos dos fármacos , Células Cultivadas , Metabolismo Energético/efeitos dos fármacos , Receptor do Peptídeo Semelhante ao Glucagon 1/fisiologia , Glucose/metabolismo , Humanos , Ácido Láctico/metabolismo , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Células de Sertoli/fisiologiaRESUMO
AIMS: We aimed to assess the alterations in specific molecular mechanisms associated with collagenolysis and their correlation in cases of stress urinary incontinence (SUI) by urethral hypermobility (UH) and by intrinsic sphincter deficiency (ISD). METHODS: We evaluated the messenger RNA (mRNA) expression of matrix metalloproteinases (MMP1, MMP2, and MMP9), specific tissue inhibitors of metalloproteinases (TIMPs), and associated proteins (TIMP1, TIMP2, and α-2-macroglobulin [A2McG]) in the suburethral tissue of women with SUI (half with SUI by UH and half with SUI by ISD) by reverse-transcriptase quantitative polymerase chain reaction and determined the correlations of the expression of these proteins on each pathological condition. RESULTS: In the suburethral tissue, we found significantly altered MMP2 mRNA levels, being higher in women with ISD than in those with UH. Still, MMP1 and MMP9 exhibited a tendency to a higher expression in women with ISD. Concerning the TIMPs expression, no significant statistical differences were found between women with UH and ISD. When evaluating the MMP/TIMP ratios, we found significant statistical differences between MMP9/TIMP1 and MMP9/A2McG. In fact, the correlations of the expression MMP9 with TIMP1 and A2McG were lost for women with UH. The ratios between MMP1/TIMP1 and MMP1/A2McG were similar, although there was a tendency of higher ratio in ISD for MMP2/TIMP2 and MMP2/A2McG. CONCLUSION: Our results point toward higher collagenolysis in the suburethral tissue of women with SUI by ISD.
Assuntos
Colágeno/metabolismo , Uretra/fisiopatologia , Doenças Uretrais/fisiopatologia , Incontinência Urinária por Estresse/metabolismo , Incontinência Urinária por Estresse/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Metaloproteinases da Matriz/biossíntese , Metaloproteinases da Matriz/genética , Pessoa de Meia-Idade , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Inibidores Teciduais de Metaloproteinases/genética , Inibidores Teciduais de Metaloproteinases/metabolismoRESUMO
PURPOSE: L-Theanine is the major free amino acid present in tea (Camellia sinensis L.). The effects of several tea constituents on male reproduction have been investigated, but L-theanine has been overlooked. Sertoli cells (SCs) are essential for the physical and nutritional support of germ cells. In this study, we aimed to investigate the ability of L-theanine to modulate important mechanisms of human SCs (hSCs) metabolism, mitochondrial function and oxidative profile, which are essential to prevent or counteract spermatogenesis disruption in several health conditions. METHODS: We evaluated the effect of a dose of L-theanine attained by tea intake (5 µM) or a pharmacological dose (50 µM) on the metabolism (proton nuclear magnetic resonance and Western blot), mitochondrial functionality (protein expression of mitochondrial complexes and JC1 ratio) and oxidative profile (carbonyl levels, nitration and lipid peroxidation) of cultured hSCs. RESULTS: Exposure of hSCs to 50 µM of L-theanine increased cell proliferation and glucose consumption. In response to this metabolic adaptation, there was an increase in mitochondrial membrane potential, which may compromise the prooxidant-antioxidant balance. Still, no alterations were observed regarding the oxidative damages. CONCLUSIONS: A pharmacological dose of L-theanine (50 µM) prompts an increase in hSCs proliferation and a higher glucose metabolization to sustain the pool of Krebs cycle intermediates, which are crucial for cellular bioenergetics and biosynthesis. This study suggests an interplay between glycolysis and glutaminolysis in the regulation of hSCs metabolism.