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Infertility is a worldwide issue impacting 15% of couples' population. Male-related infertility results in almost 50% of these cases. Considering lifestyle factors associated with infertility, here in this literature review article, we aimed to discuss training/sport effects on male-related infertility. Regarding this issue, human and animal model studies related to the subject were gathered and analysed. Exercise is well known as a general improving factor, however, excessive exercise can result in male infertility due to reduced hypothalamus-pituitary-gonadal axis (HPT) function, increased oxidative stress and chronic inflammation. Consequently, these underlying impacts result in a low testosterone production, and reduced semen quality, and can lead to infertility. In contrast, it has been revealed that exercise can improve male fertility status in lifestyle-induced infertility condition such as obesity and diabetes. Indeed, exercise, by increasing testicular antioxidant defence, reducing pro-inflammatory cytokines level and enhancing the steroidogenesis process, leads to improved spermatogenesis and semen quality in lifestyle-induced infertility. In fact, it seems that individual health status as well as exercise volume, intensity and duration are effective-involved co-factors that influence the impact that exercise will promote on male fertility. Regarding these findings, it is important to study exercise different impacts in further clinical trials in order to generate preservative guidelines for exercise and also considering exercise as a treatment option in lifestyle-induced disease management.

Varicocele mechanisms and its impact in testicular dysfunction has been studied in order to understand the pathophysiology involved in this disease. However, study designs using testicular tissues from varicocele patients are restricted due to ethical limitations. Therefore, the use of animal models, mainly rats, that mimics varicocele and its effects is an option to develop new approaches. The surgical technique, that induces the varicocele in rats, is based on the partial obstruction of the left renal vein, leading to a dilation in the left spermatic vein and consequently to the pampiniform plexus, resulting in varicocele-induced condition. Thus, the study of the cellular and molecular mechanisms involved in varicocele development can be addressed in depth. Besides the animal model goal to uncover the exact varicocele pathophysiology, varicocele induced models are the best options to develop new non-surgical and less invasive therapies. Various animal model studies designed and investigated antioxidant and anti-inflammatory agents to face varicocele conditions. Minding this fact, we tried to discuss a newly uncovered complex in varicocele condition, known as inflammasome complex. Taking into consideration the possible inflammatory state present in varicocele, the inflammasome complex has been proposed to be involved in the pathophysiology of this disease.

This study aimed to assess the effects of the inhibition of nitric oxide synthase (NOS) on events that modulate bovine in vitro oocyte maturation. Cumulus-oocyte complexes (COCs) were cultured with hemisections (HSs) of the follicular walls in a maturation medium supplemented with different concentrations (0.1-10.0 mM) of Nω-nitro-l-arginine methyl ester hydrochloride (l-NAME). Controls consisted of COCs cultured in the presence (+HSs) or absence of HSs (-HSs) with no additional l-NAME supplementation. The following parameters were assessed: oocyte nuclear maturation stage; cumulus cell (CC) membrane integrity; nitrate/nitrite, progesterone, and estradiol concentrations in the culture medium at 22 h of cultivation; and the concentrations of cGMP and cAMP in COCs during the first hour of maturation. The addition of 1.0 mM l-NAME increased the percentage of oocytes that reached metaphase II (MII) and the percentage of intact CCs (P0.05). All l-NAME concentrations reduced the nitrate/nitrite concentrations (P0.05), but none affected steroid concentrations compared with control +HSs (P0.05). The addition of 1.0 mM l-NAME reduced cGMP concentrations at 3 h and increased cAMP concentrations in the first hour of culture (P0.05). Our findings suggest that the NOS/NO/cGMP pathway participates in meiosis progression (MI to MII) of the bovine oocytes matured in vitro in the presence of hemisections of the follicular walls. Lastly, the mechanisms that lead to the progression of meiosis after NOS inhibition do not involve changes in steroid production.

Male infertility is one important factor among the multifactorial causes of couple infertility, being oxidative stress one of the main related sources. Sperm is a specialized cell extremely susceptible to stress. To understand and mitigate this event, many studies have used different antioxidants, orally or in vitro supplementation, trying to improve sperm quality and function. Considering the extensive available literature regarding approaches and attempts to solve male fertility issues, the aim of this review is evaluating the effects of antioxidant supplementation on sperm, in both humans and experimental models with animals. This review selected original data from PubMed. The keywords used were: antioxidant, sperm, male fertility, antioxidant supplementation, male infertility; and the term "rodents" was added to the descriptors “antioxidant” and “male fertility”. Only studies published in indexed journals, in English, between 2015 and 2019 were included. This review involves i) human sperm and ii) rodent sperm. For the human approach, the search retrieved 496 articles and 80 were included, among which 28 studies were of in vitro antioxidant supplementation, 19 involved oral antioxidant supplementation and the remaining 33 concerned quantification of oxidants and antioxidants already present in the seminal samples. For the rodent approach, 152 articles were retrieved and 52 were included: 3 of varicocele, 11 of diabetes, 10 of therapeutic drugs, 3 of physical exercise, 10 of environmental exposure and 3 of heat stress. The remaining studies involved oxidative stress status in experimental models. Antioxidants use for reproductive purposes is increasing in an attempt to achieve better gametes and embryos. Vitamins C, B and E, selenium and zinc are the most commonly used antioxidants, with remarkable evidences in improving pathophysiological seminal conditions. La infertilidad masculina es un factor importante entre las causas multifactoriales de infertilidad de pareja, siendo el estrés oxidativo una de las principales fuentes relacionadas. El esperma es una célula especializada que es extremadamente susceptible al estrés. Para comprender y mitigar este evento, muchos estudios han utilizado diferentes antioxidantes, suplementados por vía oral o in vitro, en un intento por mejorar la calidad y función de estos gametos. Considerando la extensa literatura disponible sobre enfoques e intentos para resolver problemas de infertilidad masculina, el objetivo de esta revisión es evaluar los efectos de la suplementación con antioxidantes en los espermatozoides, tanto en humanos como en modelos experimentales. Esta revisión seleccionó datos originales de PubMed. Las palabras clave utilizadas fueron: antioxidante, esperma, fertilidad masculina, suplementación con antioxidantes, infertilidad masculina; y se añadió el término "roedores" a los descriptores "antioxidante" y "fertilidad masculina". Solo se incluyeron estudios publicados en revistas indexadas, en inglés, entre los años de 2015 y 2019. Esta revisión incluye i) esperma humano y ii) esperma de roedor. Para el brazo humano, la búsqueda recuperó 496 artículos y se incluyeron 80, entre los cuales 28 estudios fueron suplementos de antioxidantes in vitro, 19 involucraron suplementos de antioxidantes orales y los 33 restantes se referían a la cuantificación de oxidantes y antioxidantes ya presentes en las muestras. Para el brazo de roedor, se recuperaron 152 artículos y se incluyeron 52: 3 sobre varicocele, 11 sobre diabetes, 10 sobre fármacos terapéuticos, 3 sobre ejercicio físico, 10 sobre exposición ambiental y 3 sobre estrés por calor. Los otros estudios involucraron estrés oxidativo en modelos experimentales. El uso de antioxidantes con fines reproductivos está aumentando en un intento por obtener mejores gametos y embriones. Las vitaminas C, B y E, el selenio y el zinc son los antioxidantes más comúnmente usados, con una evidencia notable para mejorar las condiciones seminales fisiopatológicas. A infertilidade masculina é um fator importante entre as causas multifatoriais da infertilidade do casal, sendo o estresse oxidativo uma das principais fontes relacionadas. O espermatozoide é uma célula especializada extremamente suscetível ao estresse. Para entender e mitigar esse evento, muitos estudos têm usado diferentes antioxidantes, suplementando via oral ou in vitro, na tentativa de melhorar a qualidade e função desses gametas. Considerando a extensa literatura disponível sobre abordagens e tentativas de resolver questões de infertilidade masculina, o objetivo desta revisão é avaliar os efeitos da suplementação com antioxidantes sobre os espermatozoides, tanto em humanos quanto em modelos experimentais com animais. Esta revisão selecionou dados originais do PubMed. As palavras-chave utilizadas foram: antioxidant, sperm, male fertility, antioxidant supplementation, male infertility; e o termo “rodents” foi adicionado aos descritores “antioxidant” e “male fertility”. Apenas estudos publicados em revistas indexadas, em inglês, entre 2015 e 2019 foram incluídos. Esta revisão envolve i) espermatozoides humanos e ii) espermatozoides de roedores. Para a abordagem humana, a busca recuperou 496 artigos e 80 foram incluídos, entre os quais 28 estudos eram de suplementação antioxidante in vitro, 19 envolviam suplementação antioxidante oral e os 33 restantes diziam respeito à quantificação de oxidantes e antioxidantes já presentes nas amostras seminais. Para a abordagem animal, 152 artigos foram recuperados e 52 foram incluídos: 3 de varicocele, 11 de diabetes, 10 de drogas terapêuticas, 3 de exercícios físicos, 10 de exposição ambiental e 3 de estresse térmico. Os demais estudos envolveram o status do estresse oxidativo em modelos experimentais. O uso de antioxidantes em técnicas de reprodução assistida vem aumentando na tentativa de obter gametas e embriões melhores. Vitaminas C, B e E, selênio e zinco são os antioxidantes mais comumente usados, com notáveis evidências na melhoria das condições seminais fisiopatológicas.

Introduction: The seminal proteome has been shown to directly influence the male fertile potential. Post-translational modifications (PTMs) are significant changes that play a role in the b...

Tema e Alcance: A estimativa da fertilidade do reprodutor é uma ferramenta importante na escolha do macho, não só porque reflete o estado individual do reprodutor, mas também porque dito resultado influencia o futuro do rebanho, a presente revisão aborda o assunto fertilidade no macho bovino desde a perspectiva da biotecnologia do sêmen. Características: descreve as características seminais que influenciam o potencial reprodutivo e apresenta de forma geral técnicas laboratoriais rotineiras e inovadoras na avaliação de espermatozoides. Documentos base na área de biotecnologia de sêmen foram utilizados na revisão assim como artigos das ultimas 4 décadas e até hoje, aspectos chaves de manuais e livros de difusão mundial complementam o acervo bibliográfico referenciado. Achados: o amplo número de estudos sobre o tema e a diversidade nos resultados, pressupõem gargalos no conhecimento que abrem uma janela na utilização de ferramentas genômicas que permitam explicar com maior acurácia os diferentes eventos fisiológicos envolvidos na expressão das características seminais referentes à fertilidade. Conclusões: a variância genética e as mudanças epigenéticas podem estar influenciando o potencial reprodutivo no macho, fenômenos funcionais ainda pouco conhecidos precisam ser elucidados no intuito de compreender, e tal vez alterar dita variação entre e inter reprodutores.