Ghrelin acts as energy status sensor of male reproduction by modulating Sertoli cells glycolytic metabolism and mitochondrial bioenergetics.

Ghrelin is a growth hormone-releasing peptide that has been suggested to interfere with spermatogenesis, though the underling mechanisms remain unknown. We studied the effect of ghrelin in human Sertoli cells (hSCs) metabolic phenotype. For that, hSCs were exposed to increasing concentrations of ghrelin (20, 100 and 500 pM) mimicking the levels reported in obese, normal weight, and severely undernourished individuals. The metabolite production/consumption was determined. The protein levels of key glycolysis-related transporters and enzymes were assessed. The lactate dehydrogenase (LDH) activity was measured. Mitochondrial complexes protein levels and mitochondria membrane potential were also measured. We showed that hSCs express the growth hormone secretagogue receptor. At the concentration present in the plasma of normal weight men, ghrelin caused a decrease of glucose consumption and mitochondrial membrane potential in hSCs, though LDH activity and lactate production remained unchanged, illustrating an alteration of glycolytic flux efficiency. Exposure of hSCs to levels of ghrelin found in the plasma of severely undernourished individuals decreased pyruvate consumption and mitochondrial complex III protein expression. All concentrations of ghrelin decreased alanine and acetate production by hSCs. Notably, the effects of ghrelin levels found in severely undernourished individuals were more pronounced in hSCs metabolic phenotype highlighting the importance of a proper eating behavior to maintain male reproductive potential. In conclusion, ghrelin acts as an energy status sensor for hSCs in a dose-dependent manner, showing an inverse association with the production of lactate, thus controlling the nutritional support of spermatogenesis.

Melatonin and male reproductive health: relevance of darkness and antioxidant properties.

The pineal hormone melatonin controls several physiological functions that reach far beyond the regulation of the circadian rhythm. Moreover, it can be produced in extra-pineal organs such as reproductive organs. The role of melatonin in the mammalian seasonal and circadian rhythm is well known. Nevertheless, its overall effect in male reproductive physiology remains largely unknown. Melatonin is a very powerful endogenous antioxidant that can also be exogenously taken safely. Interestingly, its antioxidant properties have been consistently reported to improve the male reproductive dysfunctions associated with pathological conditions and also with the exposure to toxicants. Nevertheless, the exact molecular mechanisms by which melatonin exerts its action in the male reproductive system remain a matter of debate. Herein, we propose to present an up-to-date overview of the melatonin effects in the male reproductive health and debate future directions to disclose possible sites of melatonin action in male reproductive system. We will discuss not only the role of melatonin during darkness and sleep but also the importance of the antioxidant properties of this hormone to male fertility. Since melatonin readily crosses the physiological barriers, such as the blood-testis barrier, and has a very low toxicity, it appears as an excellent candidate in the prevention and/or treatment of the multiple male reproductive dysfunctions associated with various pathologies.

Metformin and male reproduction: effects on Sertoli cell metabolism.

BACKGROUND AND PURPOSE: Metformin is commonly used to treat type 2 diabetes (T2D). While new clinical applications have been ascribed to metformin, including treatment of anovulatory infertility, its effects on male reproduction have not been investigated. The Sertoli cell (SC) is crucial for germ cell development, exerting metabolic control of spermatogenesis, therefore, we investigated the effects of metformin on SC metabolism. EXPERIMENTAL APPROACH: Rat SCs were cultured in the absence and presence of metformin (5, 50 and 500 µM). mRNA and protein levels of glucose transporters (GLUT1 and GLUT3), phosphofructokinase 1 (PFK 1), lactate dehydrogenase (LDH) and monocarboxylate transporter 4 (MCT4) were determined by quantitative PCR and Western blot respectively. LDH activity was assessed and metabolite production/consumption determined by (1) H-NMR. KEY RESULTS: Metformin (50 µM) decreased mRNA and protein levels of GLUT1, GLUT3, MCT4 and PFK 1 but did not affect LDH mRNA or protein levels. However, although glucose consumption was maintained in metformin-treated cells, LDH activity, lactate and alanine production were increased, indicating an enhanced glycolytic flux. No metabolic cytotoxicity was detected in SCs exposed to supra-pharmacological concentration of metformin. CONCLUSIONS AND IMPLICATIONS: Our results indicate that metformin: (i) decreases mRNA and protein levels of glycolysis-related transporters in SCs but increases their activity; and (ii) stimulates alanine production, which induces antioxidant activity and maintains the NADH/NAD(+) equilibrium. The increased lactate in metformin-treated SCs provides nutritional support and has an anti-apoptotic effect in developing germ cells. Thus, metformin can be considered as a suitable antidiabetic drug for male patients of reproductive age with T2D.

Effect of white tea (Camellia sinensis (L.)) extract in the glycolytic profile of Sertoli cell.

PURPOSE: Many health benefits have been attributed to tea (Camellia sinensis (L.)), and tea infusions are used as dietary agent and included in food supplements. Herein, we report the effect of a white tea (WTEA) extract in Sertoli cell (SC) metabolism. The SC is responsible for the nutritional support of the developing germ cells. METHODS: An aqueous WTEA extract was prepared and analyzed by (1)H-NMR. Rat SCs were cultured with or without the WTEA extract. mRNA and protein levels of glucose transporters (GLUT1 and GLUT3), phosphofructokinase, lactate dehydrogenase (LDH) and monocarboxylate transporter 4 were determined by qPCR and western blot. LDH activity was assessed and metabolite production/consumption determined by (1)H-NMR. RESULTS: WTEA-exposed SCs presented decreased protein and mRNA levels of GLUT1 and decreased glucose uptake. However, intracellular LDH activity was increased and SC lactate production was stimulated by the presence of the WTEA extract. Interestingly, alanine production was also found to be stimulated in WTEA extract-exposed SCs. CONCLUSION: WTEA extract altered the glycolytic profile of cultured SCs, stimulating lactate production. Since lactate is used as metabolic substrate and has an anti-apoptotic effect in the developing germ cells, the supplementation with WTEA extract may be advantageous to improve male reproductive health.

Insulin deprivation decreases caspase-dependent apoptotic signaling in cultured rat sertoli cells.

Insulin is essential for the regulation of glucose homeostasis. Insulin dysfunction occurs in several pathologies, such as diabetes mellitus, which is associated with fertility problems. Somatic Sertoli cells (SCs) not only metabolize glucose to lactate, which is the central energy source used by developing germ cells, but also determine the germ cell population size. If a deregulation in SCs apoptosis occurs, it will affect germ cells, compromising spermatogenesis. As SCs apoptotic signaling is a hormonally regulated process, we hypothesized that the lack of insulin could lead to alterations in apoptotic signaling. Therefore, we examined the effect of insulin deprivation on several markers of apoptotic signaling in cultured rat SCs. We determined mRNA and protein expression of apoptotic markers as well as caspase-3 activity. SCs cultured in insulin deprivation demonstrated a significant decrease on mRNA levels of p53, Bax, caspase-9, and caspase-3 followed by a significant increase of Bax and decrease of caspase-9 protein levels relatively to the control. Caspase-3 activity was also decreased in SCs cultured in insulin deprivation conditions. Our results show that insulin deprivation decreases caspase-dependent apoptotic signaling in cultured rat SCs evidencing a possible mechanism by which lack of insulin can affect spermatogenesis and fertility.

Molecular basis of bicarbonate membrane transport in the male reproductive tract.

Bicarbonate (HCO3⁻) membrane transport systems are crucial players in the physiology of several tissues. The molecular basis of HCO3⁻ membrane transport is of major physiological relevance since this ion is involved in the establishment of intracellular and extracellular ionic composition, osmolariy and pH. The membrane HCO3⁻ transporters are divided in two main families: solute carrier 4 (SLC4) and solute carrier 26 (SLC26), although HCO3⁻ concentration can also be regulated by the cystic fibrosis transmembrane regulator (CFTR). In most tissues the SLC4 family represents the majority of HCO3⁻ transporters members, which can be divided in two subgroups: the Na⁺-dependent and the Na⁺-independent transporters. The SLC26 family consists of ten members that can transport diverse ions besides HCO3⁻. In the male reproductive tract, HCO3⁻ transport occurs in several processes in order to assure a correct pursuance of the spermatogenetic event and spermatozoa capacitation, being also necessary for egg fertilization. Indeed, the formation of competent spermatozoa, the maintenance of an adequate ductal luminal milieu and spermatozoa capacitation are highly dependent of ionic balance and pH. Perturbations in these processes result in reduced male reproductive health and consequently male subfertility and/or infertility. Thus, it is imperative to understand HCO3⁻ transport dynamics in order to identify and counteract possible alterations related with reduced male fertility caused by pathological conditions. Herein, we will review the major families and subfamilies of HCO3⁻ membrane transport, discussing the molecular basis of HCO3⁻ transport in the male reproductive tract and its role in male-associated subfertility and/or infertility.

Molecular mechanisms beyond glucose transport in diabetes-related male infertility.

Diabetes mellitus (DM) is one of the greatest public health threats in modern societies. Although during a few years it was suggested that DM had no significant effect in male reproductive function, this view has been challenged in recent years. The increasing incidence of DM worldwide will inevitably result in a higher prevalence of this pathology in men of reproductive age and subfertility or infertility associated with DM is expected to dramatically rise in upcoming years. From a clinical perspective, the evaluation of semen parameters, as well as spermatozoa deoxyribonucleic acid (DNA) integrity, are often studied due to their direct implications in natural and assisted conception. Nevertheless, recent studies based on the molecular mechanisms beyond glucose transport in testicular cells provide new insights in DM-induced alterations in male reproductive health. Testicular cells have their own glucose sensing machinery that react to hormonal fluctuations and have several mechanisms to counteract hyper- and hypoglycemic events. Moreover, the metabolic cooperation between testicular cells is crucial for normal spermatogenesis. Sertoli cells (SCs), which are the main components of blood-testis barrier, are not only responsible for the physical support of germ cells but also for lactate production that is then metabolized by the developing germ cells. Any alteration in this tied metabolic cooperation may have a dramatic consequence in male fertility potential. Therefore, we present an overview of the clinical significance of DM in the male reproductive health with emphasis on the molecular mechanisms beyond glucose fluctuation and transport in testicular cells.

Regulation of apoptotic signaling pathways by 5α-dihydrotestosterone and 17ß-estradiol in immature rat Sertoli cells.

Apoptosis is an important regulatory event in testicular homeostasis and optimization of sperm production. Sertoli cells (SCs) form the blood-testis barrier creating a special microenvironment where germ cells develop and are under strict hormonal control. Estrogens and androgens are known to play critical roles in SCs functioning, improving their in vitro survival by preventing apoptotic progression. Herein, we studied the influence of 17ß-estradiol (E2) and 5α-dihydrotestosterone (DHT) on the apoptotic signaling pathways of immature rat cultured SCs. For that we chose key points of the apoptotic pathway that interact with the mitochondria and evaluated the mRNA expression and/or protein levels of several apoptotic markers such as p53, the anti-apoptotic protein Bcl2, the pro-apoptotic Bcl2 family member Bax, the apoptosis-inducing factor (AIF) and caspase-3 and 9. Caspase-3 activity and DNA fragmentation were also evaluated as endpoint markers of apoptosis. E2 and DHT down-regulated the mRNA transcript levels of p53, Bax, caspase-9 and caspase-3. The protein levels of AIF were reduced after DHT treatment while E2-treated cells presented decreased levels of cleaved caspase-9 protein. Moreover, Bax/Bcl2 ratio was significantly decreased in E2-treated cells. The apoptotic endpoints caspase-3 activity and DNA fragmentation presented significant decreased levels after hormonal treatment. Taken together, these results show that E2 and DHT act as apoptotic signaling modulators in in vitro immature rat SCs suggesting that androgens and estrogens may be capable of modulating independent pathways of the apoptotic event by regulating different pro-apoptotic factors.

Consideracoes sobre o bloqueio das contracoes uterinas. / Blocking of uterine contractions

Os autores fazem algumas consideracoes sobre o uso dos bloqueadores das contracoes uterinas analisando em separado os mais importantes beta-bloqueadores, os antiprostaglandinicos e o inibidor da ocitocina. Antes procuram relembrar o mecanismo das contracoes uterinas no desencadear do trabalho de parto e baseado neste mecanismo utilizar os metodos que os bloqueiam

Tratamento das alteracoes psiquicas e vasomotoras da pos-menopausa com veralipride. / Treatment of post-menopause's psychic and vasomotor changes with veralipride

Os autores, em estudo duplo-cego com veralipride e placebo, em 50 pacientes com menopausa natural e cirurgica, tendo os sintomas psiquicos do climaterio, chegaram a conclusao de que a melhora da sintomatologia foi acentuada com o uso do medicamento Usaram-no na dose diaria de 100 mg por 20 dias. A melhora dos sintomas foi de 74,6% sendo que 70,73% das pacientes deixaram de se queixar dos sintomas, enquanto que com o placebo 22,62% das pacientes ficaram assintomaticas e 39,1% tiveram diminuicao dos sintomas. Relatam os autores que nao observaram nenhum caso de galactorreia e nenhum caso de efeito colateral. Concluem dizendo que o veralipride deve ser usado tanto na pos-menopausa quanto na pre-menopausa e, se necessario for, podera ser associado aos estrogenios em menores doses

Novo esquema terapeutico para o tratamento de processos inflamatorios pelvicos com o fentiazac. / A new therapeutic scheme for the treatment of pelvic inflammatory diseases with fentiazac

O autor estudou a acao do fentiazac em 50 pacientes, portadores de processos inflamatorios pelvicos com queixas bastante variaveis, mas estando a dor presente em todos os casos.O fentiazac foi administrado em drageas de 100 mg duas vezes ao dia e um supositorio de 200 mg a noite, por um periodo de 10 dias. Em 15 casos, devido a presenca de leucorreia, associou-se outros medicamentos especificos sob forma de creme vaginal. Os resultados obtidos foram: otimos em 56% dos casos, bons em 34% e regulares em 10%. Nenhum efeito colateral foi observado

Uso do lactobacilo acidofilo no fluxo vaginal. / Use of Lactobacillus acidophilus in vaginal discharge

O A. empregou em ensaio clinico aberto, o Lactobacillus acidophilus para o tratamento do fluxo vaginal em 40 pacientes com etiologias diversas. Fez um relato da importancia do pH vaginal como meio de defesa da vagina e a responsabilidade do lactobacilo em manter o pH vaginal pela transformacao do glicogenio em acido lactico. Relata, igualmente, a experiencia de autores brasileiros e estrangeiros com a lactobaciloterapia em patologias vaginais, a mais antiga sendo a de Sandler, na Inglaterra que ha mais de 30 anos a emprega para o tratamento da candidiase e sempre faz uso de terapeutica com antibioticos. Mostra seus resultados com o uso exclusivo do lactobacilo em 37 pacientes e associado em 3 apresentando resultados excelentes em 50.0% e melhorados em 47,5% do casos, totalizando 97,5% de resultados terapeuticos. A tolerabilidade foi excelente, nao havendo referencia a nenhum efeito secundario. Termina dizendo que o uso exclusivo ou associado do lactobacilo e mais uma opcao para o tratamento do fluxo vaginal de qualquer etiologia

Estudo comparativo dexon x catgut em cirurgia ginecologica. / Comparative study between dexon and catgut in gynecologic surgery

O presenta estudo refere-se a uma amostragem de 100 pacientes submetidos a cirurgia ginecologica ou obstetrica no Hospital - Escola da Universidade Federal de Juiz de Fora e Casa de Saude e Maternidade Juiz de Fora, nos quais foram utilizados, comparativamente,fios de sutura de Dexon (PGA), num grupo de 50 pacientes e Catgut no grupo controle (50 pacientes). Os dois grupos foram comparados quanto a eficacia e tolerabilidade, destacando-se a regressao e o tempo de evolucao dos fenomenos inflamatorios (edema, eritema, dor, secrecao purulenta, hematoma) no pos-operatorio, bem como outros fatores concomitantes (presenca de complicacao pos-operatoria, retirada de sutura da pele e cicatrizacao final). Registrou-se nitida superioridade do PGA sobre o Catgut, principalmente na avaliacao dos sinais de dor, eritema e edema local da ferida operatoria que foram muito inferiores aos registrados com o Catgut no grupo controle, considerando o periodo equivalente de evolucao pos-operatoria

Uso de bromopride nas nauseas e vomitos do pos-operatorio de cirurgia ginecologica. / Use of bromopride on nauseas and vomiting due to gynecologic surgery

Os Autores usaram o bromopride em 60 pacientes no pos-operatorio de cirurgia ginecologica para avaliar sua acao antiemetica. O tipo de cirurgia foi o mais variado e a anestesia usada foi, em 20 casos, a geral e, em 40 casos, a raquidiana. O medicamento foi usado sob a forma injetavel no primeiro dia de pos-operatorio e depois sob a forma de capsulas.Os autores encontraram os seguintes resultados: otimos em 26,7%; bons em 46,7%; regulares em 20% e nulos em 6,6%. Observaram que, entre os resultados otimos e bons, a percentagem foi de 73,4%, nao havendo efeitos colaterais. Concluem os autores que o bromopride e o meio terapeutico a ser usado para se evitar as nauseas e vomitos do pos-operatorio

[Treatment of psychic features of feminine climacteric with estrogens (author's transl)]. / Tratamento dos fatores psiquicos do climaterio feminino com estrogenos.

PIP: This study analyzes the action of some estrogens on psychological alterations caused by menopause. Psychological alterations considered were headache, tiredness, depression, insomnia, nervousness, and others. 2000 patients were observed and treated mostly with estriol. 81.6% of patients were white, 52.2% were between 46-50, 43.4% were postmenopausal, and 31.7% were menopausal. After 3 months of treatment a significant improvement was noted in all patients, thus proving the beneficial effects of estrogen therapy before, during, and after menopause. The article includes a detailed review of the published literature on the subject.^ieng