Arabidopsis CALCINEURIN B-LIKE10 Functions Independently of the SOS Pathway during Reproductive Development in Saline Conditions1[OPEN

PubMed Central

Smith, Steven E.; Schumaker, Karen S.

2016-01-01

The accumulation of sodium in soil (saline conditions) negatively affects plant growth and development. The Salt Overly Sensitive (SOS) pathway in Arabidopsis (Arabidopsis thaliana) functions to remove sodium from the cytosol during vegetative development preventing its accumulation to toxic levels. In this pathway, the SOS3 and CALCINEURIN B-LIKE10 (CBL10) calcium sensors interact with the SOS2 protein kinase to activate sodium/proton exchange at the plasma membrane (SOS1) or vacuolar membrane. To determine if the same pathway functions during reproductive development in response to salt, fertility was analyzed in wild type and the SOS pathway mutants grown in saline conditions. In response to salt, CBL10 functions early in reproductive development before fertilization, while SOS1 functions mostly after fertilization when seed development begins. Neither SOS2 nor SOS3 function in reproductive development in response to salt. Loss of CBL10 function resulted in reduced anther dehiscence, shortened stamen filaments, and aborted pollen development. In addition, cbl10 mutant pistils could not sustain the growth of wild-type pollen tubes. These results suggest that CBL10 is critical for reproductive development in the presence of salt and that it functions in different pathways during vegetative and reproductive development. PMID:26979332

Food supplementation and testosterone interact to influence reproductive behavior and immune function in Sceloporus graciosus.

PubMed

Ruiz, Mayté; French, Susannah S; Demas, Gregory E; Martins, Emília P

2010-02-01

The energetic resources in an organism's environment are essential for executing a wide range of life-history functions, including immunity and reproduction. Most energetic budgets, however, are limited, which can lead to trade-offs among competing functions. Increasing reproductive effort tends to decrease immunity in many cases, and increasing total energy via supplemental feedings can eliminate this effect. Testosterone (T), an important regulator of reproduction, and food availability are thus both potential factors regulating life-history processes, yet they are often tested in isolation of each other. In this study, we considered the effect of both food availability and elevated T on immune function and reproductive behavior in sagebrush lizards, Sceloporus graciosus, to assess how T and energy availability affect these trade-offs. We experimentally manipulated diet (via supplemental feedings) and T (via dermal patches) in males from a natural population. We determined innate immune response by calculating the bacterial killing capability of collected plasma exposed to Escherichia coli ex vivo. We measured reproductive behavior by counting the number of courtship displays produced in a 20-min sampling period. We observed an interactive effect of food availability and T-patch on immune function, with food supplementation increasing immunity in T-patch lizards. Additionally, T increased courtship displays in control food lizards. Lizards with supplemental food had higher circulating T than controls. Collectively, this study shows that the energetic state of the animal plays a critical role in modulating the interactions among T, behavior and immunity in sagebrush lizards and likely other species. Copyright 2009 Elsevier Inc. All rights reserved.

Food supplementation and testosterone interact to influence reproductive behavior and immune function in Sceloporous graciosus

PubMed Central

Ruiz, Mayté; French, Susannah S.; Demas, Gregory E.; Martins, Emília P.

2009-01-01

The energetic resources in an organism’s environment are essential for executing a wide range of life history functions, including immunity and reproduction. Most energetic budgets, however, are limited, which can lead to trade-offs among competing functions. Increasing reproductive effort tends to decrease immunity in many cases; and increasing total energy via supplemental feedings can eliminate this effect. Testosterone (T), an important regulator of reproduction, and food availability are thus both potential factors regulating life-history processes, yet they are often tested in isolation of each other. In this study, we considered the effect of both food availability and elevated T on immune function and reproductive behavior in sagebrush lizards, Sceloporus graciosus, to assess how T and energy availability affect these trade-offs. We experimentally manipulated diet (via supplemental feedings) and T (via dermal patches) in males from a natural population. We determined innate immune response by calculating the bacterial killing capability of collected plasma exposed to E. coli ex vivo. We measured reproductive behavior by counting the number of courtship displays produced in a 20-min sampling period. We observed an interactive effect of food availability and T-patch on immune function, with food supplementation increasing immunity in T-patch lizards. Additionally, T increased courtship displays in control food lizards. Lizards with supplemental food had higher circulating T than controls. Collectively, this study shows that the energetic state of the animal plays a critical role in modulating the interactions among T, behavior and immunity in sagebrush lizards and likely other species. PMID:19800885

Nuclear Receptor Coactivator Function in Reproductive Physiology and Behavior

PubMed Central

Molenda, Heather A.; Kilts, Caitlin P.; Allen, Rachel L.; Tetel, Marc J.

2009-01-01

Gonadal steroid hormones act throughout the body to elicit changes in gene expression that result in profound effects on reproductive physiology and behavior. Steroid hormones exert many of these effects by binding to their respective intracellular receptors, which are members of a nuclear receptor superfamily of transcriptional activators. A variety of in vitro studies indicate that nuclear receptor coactivators are required for efficient transcriptional activity of steroid receptors. Many of these coactivators are found in a variety of steroid hormone-responsive reproductive tissues, including the reproductive tract, mammary gland, and brain. While many nuclear receptor coactivators have been investigated in vitro, we are only now beginning to understand their function in reproductive physiology and behavior. In this review, we discuss the general mechanisms of action of nuclear receptor coactivators in steroid-dependent gene transcription. We then review some recent and exciting findings on the function of nuclear receptor coactivators in steroid-dependent brain development and reproductive physiology and behavior. PMID:12855594

Honey and honey-based sugars partially affect reproductive trade-offs in parasitoids exhibiting different life-history and reproductive strategies.

PubMed

Harvey, Jeffrey A; Essens, Tijl A; Las, Rutger A; van Veen, Cindy; Visser, Bertanne; Ellers, Jacintha; Heinen, Robin; Gols, Rieta

2017-04-01

Adult dietary regimes in insects may affect egg production, fecundity and ultimately fitness. This is especially relevant in parasitoid wasps where many species serve as important biological control agents of agricultural pests. Here, we tested the effect of honey and sugar diets on daily fecundity schedules, lifetime reproductive success and longevity in four species of parasitoid wasps when reared on their respective hosts. The parasitoid species were selected based on dichotomies in host usage strategies and reproductive traits. Gelis agilis and G. areator are idiobiont ecto-parasitoids that develop in non-growing hosts, feed on protein-rich host fluids to maximize reproduction as adults and produce small numbers of large eggs. Meteorus pulchricornis and Microplitis mediator are koinobiont endoparasitoids that develop inside the bodies of growing hosts, do not host-feed, and produce greater numbers of small eggs. Parasitoids were reared on diets of either pure honey (containing trace amounts of proteins), heated honey (with denatured proteins) and a honey-mimic containing sugars only. We hypothesized that the benefits of proteins in honey would enhance reproduction in the ectoparasitoids due to their high metabolic investment per egg, but not in the koinobionts. Pure honey diet resulted in higher lifetime fecundity in G. agilis compared with the honey-mimic, whereas in both koinobionts, reproductive success did not vary significantly with diet. Longevity was less affected by diet in all of the parasitoids, although there were variable trade-offs between host access and longevity in the four species. We argue that there are both trait-based and association-specific effects of supplementary nutrients in honey on reproductive investment and success in parasitoid wasps. Copyright © 2016 Elsevier Ltd. All rights reserved.

Anthropogenic Matrices Favor Homogenization of Tree Reproductive Functions in a Highly Fragmented Landscape.

PubMed

Carneiro, Magda Silva; Campos, Caroline Cambraia Furtado; Beijo, Luiz Alberto; Ramos, Flavio Nunes

2016-01-01

Species homogenization or floristic differentiation are two possible consequences of the fragmentation process in plant communities. Despite the few studies, it seems clear that fragments with low forest cover inserted in anthropogenic matrices are more likely to experience floristic homogenization. However, the homogenization process has two other components, genetic and functional, which have not been investigated. The purpose of this study was to verify whether there was homogenization of tree reproductive functions in a fragmented landscape and, if found, to determine how the process was influenced by landscape composition. The study was conducted in eight fragments in southwest Brazil. The study was conducted in eight fragments in southwestern Brazil. In each fragment, all individual trees were sampled that had a diameter at breast height ≥3 cm, in ten plots (0.2 ha) and, classified within 26 reproductive functional types (RFTs). The process of functional homogenization was evaluated using additive partitioning of diversity. Additionally, the effect of landscape composition on functional diversity and on the number of individuals within each RFT was evaluated using a generalized linear mixed model. appeared to be in a process of functional homogenization (dominance of RFTs, alpha diversity lower than expected by chance and and low beta diversity). More than 50% of the RFTs and the functional diversity were affected by the landscape parameters. In general, the percentage of forest cover has a positive effect on RFTs while the percentage of coffee matrix has a negative one. The process of functional homogenization has serious consequences for biodiversity conservation because some functions may disappear that, in the long term, would threaten the fragments. This study contributes to a better understanding of how landscape changes affect the functional diversity, abundance of individuals in RFTs and the process of functional homogenization, as well as how to

Anthropogenic Matrices Favor Homogenization of Tree Reproductive Functions in a Highly Fragmented Landscape

PubMed Central

2016-01-01

Species homogenization or floristic differentiation are two possible consequences of the fragmentation process in plant communities. Despite the few studies, it seems clear that fragments with low forest cover inserted in anthropogenic matrices are more likely to experience floristic homogenization. However, the homogenization process has two other components, genetic and functional, which have not been investigated. The purpose of this study was to verify whether there was homogenization of tree reproductive functions in a fragmented landscape and, if found, to determine how the process was influenced by landscape composition. The study was conducted in eight fragments in southwest Brazil. The study was conducted in eight fragments in southwestern Brazil. In each fragment, all individual trees were sampled that had a diameter at breast height ≥3 cm, in ten plots (0.2 ha) and, classified within 26 reproductive functional types (RFTs). The process of functional homogenization was evaluated using additive partitioning of diversity. Additionally, the effect of landscape composition on functional diversity and on the number of individuals within each RFT was evaluated using a generalized linear mixed model. appeared to be in a process of functional homogenization (dominance of RFTs, alpha diversity lower than expected by chance and and low beta diversity). More than 50% of the RFTs and the functional diversity were affected by the landscape parameters. In general, the percentage of forest cover has a positive effect on RFTs while the percentage of coffee matrix has a negative one. The process of functional homogenization has serious consequences for biodiversity conservation because some functions may disappear that, in the long term, would threaten the fragments. This study contributes to a better understanding of how landscape changes affect the functional diversity, abundance of individuals in RFTs and the process of functional homogenization, as well as how to

Mutations and polymorphisms in FSH receptor: functional implications in human reproduction.

PubMed

Desai, Swapna S; Roy, Binita Sur; Mahale, Smita D

2013-12-01

FSH brings about its physiological actions by activating a specific receptor located on target cells. Normal functioning of the FSH receptor (FSHR) is crucial for follicular development and estradiol production in females and for the regulation of Sertoli cell function and spermatogenesis in males. In the last two decades, the number of inactivating and activating mutations, single nucleotide polymorphisms, and spliced variants of FSHR gene has been identified in selected infertile cases. Information on genotype-phenotype correlation and in vitro functional characterization of the mutants has helped in understanding the possible genetic cause for female infertility in affected individuals. The information is also being used to dissect various extracellular and intracellular events involved in hormone-receptor interaction by studying the differences in the properties of the mutant receptor when compared with WT receptor. Studies on polymorphisms in the FSHR gene have shown variability in clinical outcome among women treated with FSH. These observations are being explored to develop molecular markers to predict the optimum dose of FSH required for controlled ovarian hyperstimulation. Pharmacogenetics is an emerging field in this area that aims at designing individual treatment protocols for reproductive abnormalities based on FSHR gene polymorphisms. The present review discusses the current knowledge of various genetic alterations in FSHR and their impact on receptor function in the female reproductive system.

DEHP impairs zebrafish reproduction by affecting critical factors in oogenesis.

PubMed

Carnevali, Oliana; Tosti, Luca; Speciale, Claudia; Peng, Chun; Zhu, Yong; Maradonna, Francesca

2010-04-15

Public concerns on phthalates distributions in the environment have been increasing since they can cause liver cancer, structural abnormalities and reduce sperm counts in male reproductive system. However, few data are actually available on the effects of Di-(2-ethylhexyl)-phthalate (DEHP) in female reproductive system. The aim of this study was to assess the impacts of DEHP on zebrafish oogenesis and embryo production. Female Danio rerio were exposed to environmentally relevant doses of DEHP and a significant decrease in ovulation and embryo production was observed. The effects of DEHP on several key regulators of oocyte maturation and ovulation including bone morphogenetic protein-15 (BMP15), luteinizing hormone receptor (LHR), membrane progesterone receptors (mPRs) and cyclooxygenase (COX)-2 (ptgs2) were determined by real time PCR. The expressions of BMP15 and mPR proteins were further determined by Western analyses to strengthen molecular findings. Moreover, plasma vitellogenin (vtg) titers were assayed by an ELISA procedure to determine the estrogenic effects of DEHP and its effects on oocyte growth. A significant reduction of fecundity in fish exposed to DEHP was observed. The reduced reproductive capacity was associated with an increase in ovarian BMP15 levels. This rise, in turn, was concomitant with a significant reduction in LHR and mPRbeta levels. Finally, ptgs2 expression, the final trigger of ovulation, was also decreased by DEHP. By an in vitro maturation assay, the inhibitory effect of DEHP on germinal vesicle breakdown was further confirmed. In conclusion, DEHP affecting signals involved in oocyte growth (vtg), maturation (BMP15, LHR, mPRs,) and ovulation (ptgs2), deeply impairs ovarian functions with serious consequences on embryo production. Since there is a significant genetic similarity between D.rerio and humans, the harmful effects observed at oocyte level may be relevant for further molecular studies on humans.

Effects of a group-based reproductive management extension programme on key management outcomes affecting reproductive performance.

PubMed

Brownlie, Tom S; Morton, John M; Heuer, Cord; McDougall, Scott

2015-02-01

A group-based reproductive management extension programme has been designed to help managers of dairy herds improve herd reproductive performance. The aims of this study were, firstly, to assess effects of participation by key decision makers (KDMs) in a farmer action group programme in 2009 and 2010 on six key management outcomes (KMOs) that affect reproductive performance over 2 years (2009-2010 and 2010-2011), and secondly, to describe KDM intentions to change management behaviour(s) affecting each management outcome after participation in the programme. Seasonal calving dairy herds from four regions of New Zealand were enrolled in the study. Intentions to modify management behaviour were recorded using the formal written action plans developed during the extension programme. KMOs assessed were calving pattern of the herd, pre-calving heifer liveweight, pre-calving and premating body condition score (BCS), oestrus detection, anoestrus cow management and bull management. Participation was associated with improvements in heifer liveweight, more heifers calving in the first 6 weeks of the seasonal calving period, premating BCS and oestrus detection. No significant effects were observed on anoestrus cow management or bull management. KDMs with greater numbers of proposed actions had lower 6 week in-calf rates in the second study year than KDMs who proposed fewer actions. A more effective strategy to ensure more appropriate objectives is proposed. Strategies to help KDMs to implement proposed actions more successfully should be investigated to improve the programme further. Copyright © 2014 Elsevier Ltd. All rights reserved.

Effects of functionally asexual reproduction on quantitative genetic variation in the evening primroses (Oenothera, Onagraceae).

PubMed

Godfrey, Ryan M; Johnson, Marc T J

2014-11-01

It has long been predicted that a loss of sexual reproduction leads to decreased heritable variation within populations and increased differentiation between populations. Despite an abundance of theory, there are few empirical tests of how sex affects genetic variation in phenotypic traits, especially for plants. Here we test whether repeated losses of two critical components of sex (recombination and segregation) in the evening primroses (Oenothera L., Onagraceae) affect quantitative genetic variation within and between populations. We sampled multiple genetic families from 3-5 populations from each of eight Oenothera species, which represented four independent transitions between sexual reproduction and a functionally asexual genetic system called "permanent translocation heterozygosity." We used quantitative genetics methods to partition genetic variation within and between populations for eight plant traits related to growth, leaf physiology, flowering, and resistance to herbivores. Heritability was, on average, 74% higher in sexual Oenothera populations than in functionally asexual populations, with plant growth rate, specific leaf area, and the percentage of leaf water content showing the strongest differences. By contrast, genetic differentiation among populations was 2.8× higher in functionally asexual vs. sexual Oenothera species. This difference was particularly strong for specific leaf area. Sexual populations tended to exhibit higher genetic correlations among traits, but this difference was weakly supported. These results support the prediction that sexual reproduction maintains higher genetic variation within populations, which may facilitate adaptive evolution. We also found partial support for the prediction that a loss of sex leads to greater population differentiation, which may elevate speciation rates. © 2014 Botanical Society of America, Inc.

Functional roles of cell surface peptidases in reproductive organs

PubMed Central

2004-01-01

A number of biologically active peptides have been proposed to regulate function and differentiation of reproductive organs in an autocrine and/or paracrine fashion. Regulation of the local concentrations of these peptides is one of the important factors influencing their physiological effects on target cells. Membrane‐bound cell surface peptidases can activate or inactivate biologically active peptides before peptide factors access their receptors on the cell surface. Aminopeptidase A (EC 3.4.11.7), placental leucine aminopeptidase (EC 3.4.11.3), aminopeptidase‐N/CD13 (EC 3.4.11.2), dipeptidyl peptidases IV/CD26 (EC.3.4.14.5), carboxypeptidase‐M (EC 3.4.17.12), neutral endopeptidase/CD10 (EC 3.4.24.11) and endothelin converting enzyme‐1 (EC 3.4.23) are differentially expressed on the ovary, endometrium and placenta. The inhibition of enzyme activity affects steroid hormone production by granulosa and thecal cells, decidualization of endometrium and migration of extravillous trophoblasts. These findings suggest that membrane‐bound cell surface peptidases are local regulators for cellular growth and differentiation in reproductive organs by controlling extracellular concentration of peptide factors. (Reprod Med Biol 2004; 3: 165 –176) PMID:29662383

The role of early life nutrition in programming of reproductive function.

PubMed

Chadio, S; Kotsampasi, B

2014-02-01

Accumulating evidence suggest that the concept of programming can also be applied to reproductive development and function, representing an ever expanding research area. Recently issues such as peri- or even preconceptional nutrition, transgenerational effects and underlying mechanisms have received considerable attention. The present chapter presents the existed evidence and reviews the available data from numerous animal and human studies on the effects of early life nutritional environment on adult reproductive function. Specific outcomes depend on the severity, duration and stage of development when nutritional perturbations are imposed, while sex-specific effects are also manifested. Apart from undernutrition, effects of relative overnutrition as well as the complex interactions between pre- and postnatal nutrition is of high importance, especially in the context of our days obesity epidemic. Mechanisms underlying reproductive programming are yet unclear, but may include a role for epigenetic modifications. Epigenetic modulation of critical genes involved in the control of reproductive function and potential intergenerational effects represent an exciting area of interdisciplinary research toward the development of new nutritional approaches during pre- and postnatal periods to ensure reproductive health in later life.

Regulation of the activins-follistatins-inhibins axis by energy status: Impact on reproductive function.

PubMed

Perakakis, Nikolaos; Upadhyay, Jagriti; Ghaly, Wael; Chen, Joyce; Chrysafi, Pavlina; Anastasilakis, Athanasios D; Mantzoros, Christos S

2018-05-09

We have previously demonstrated that the adipose tissue derived hormone leptin controls reproductive function by regulating the hypothalamic-pituitary-gonadal axis in response to energy deficiency. Here, we evaluate the activins-follistatins-inhibins (AFI) axis during acute (short-term fasting in healthy people) and chronic energy deficiency (women with hypothalamic amenorrhea due to strenuous exercise [HA]) and investigate their relation to leptin and reproductive function in healthy subjects and subjects with HA. The AFI axis was investigated in: a) A double-blinded study in healthy subjects having three randomly assigned admissions, each time for four days: in the isocaloric fed state, complete fasting with placebo treatment, complete fasting with leptin replacement, b) A case-control study comparing women with HA vs healthy controls, c) An open-label interventional study investigating leptin treatment in women with HA over a period of up to three months, d) A randomized interventional trial investigating leptin treatment vs placebo in women with HA for nine months. The circulating levels of activin A, activin B, follistatin and follistatin-like 3 change robustly in response to acute and chronic energy deficiency. Leptin replacement in acute energy deprivation does not affect the levels of these hormones suggesting an independent regulation by these two hormonal pathways. In chronic energy deficiency, leptin replacement restores only activin B levels, which are in turn associated with an increase in the number of dominant follicles. We demonstrate for the first time that the AFI axis is affected both by acute and chronic energy deficiency. Partial restoration of a component of the axis, i.e. activin B only, through leptin replacement is associated with improved reproductive function in women with HA. Copyright © 2018. Published by Elsevier Inc.

Reproductive toxicity: Male and female reproductive systems as targets for chemical injury

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mattison, D.R.; Plowchalk, D.R.; Meadows, M.J.

On the basis of current knowledge of reproductive biology and toxicology, it is apparent that chemicals affecting reproduction may elicit their effects at a number of sites in both the male and the female reproductive system. This multiplicity of targets is attributable to the dynamic nature of the reproductive system, in which the hypothalamic-pituitary-gonadal axis is controlled by precise positive and negative feedback mechanisms among its components. Interference by a xenobiotic at any level in either the male or the female reproductive system may ultimately impair hypothalamic or pituitary function. Normal gonadal processes such as spermatogenesis or oogenesis, ejaculation ormore » ovulation, hormone production by Leydig or granulosa cells, and the structure or function of the accessory reproductive structures (e.g., epididymis, fallopian tube) also appear vulnerable to xenobiotics. The reproductive system is a complex one that requires local and circulating hormones for control. This brief review illustrates a system for characterizing the mechanism of action of reproductive toxicants, as well as for defining the sites available for disruption of reproduction. Unfortunately, at present, data addressing the actual vulnerability of reproduction are sorely lacking. However, when experiments have been conducted and combined with epidemiologic data or clinical observation, it has been possible to demonstrate impairment of reproductive processes by xenobiotics. The role of environmental exposure to xenobiotics in the increase in infertility that has been observed remains to be defined. 87 references.« less

Melatonin and male reproduction.

PubMed

Li, Chunjin; Zhou, Xu

2015-06-15

Melatonin is a neurohormone secreted by the pineal gland whose concentrations in the body are regulated by both the dark-light and seasonal cycles. The reproductive function of seasonal breeding animals is clearly influenced by the circadian variation in melatonin levels. Moreover, a growing body of evidence indicates that melatonin has important effects in the reproduction of some non-seasonal breeding animals. In males, melatonin affects reproductive regulation in three main ways. First, it regulates the secretion of two key neurohormones, GnRH and LH. Second, it regulates testosterone synthesis and testicular maturation. Third, as a potent free radical scavenger that is both lipophilic and hydrophilic, it prevents testicular damage caused by environmental toxins or inflammation. This review summarizes the existing data on the possible biological roles of melatonin in male reproduction. Overall, the literature data indicate that melatonin affects the secretion of both gonadotropins and testosterone while also improving sperm quality. This implies that it has important effects on the regulation of testicular development and male reproduction. Copyright © 2015. Published by Elsevier B.V.

Effect of altered reproductive function and lowered testosterone levels on bone density in male endurance athletes.

PubMed

Bennell, K L; Brukner, P D; Malcolm, S A

1996-09-01

It is apparent that bone density in male athletes can be reduced without a concomitant decrease in testosterone, suggesting that bone density and testosterone concentrations in the normal range are not closely related in male athletes. Further research is necessary to monitor concurrent changes in bone density and testosterone over a period of time in exercising males. In any case, the effect of exercise on the male reproductive system does not appear as extreme as that which can occur in female athletes, and any impact on bone density is not nearly as evident. These results imply that factors apart from testosterone concentrations must be responsible for the observed osteopenia in some male athletes. Many factors have the potential to adversely affect bone density, independently of alterations in reproductive function. These include low calcium intake, energy deficit, weight loss, psychological stress, and low body fat, all of which may be associated with intense endurance training. Future research investigating skeletal health in male athletes should include a thorough assessment of reproductive function in addition to these other factors.

Diabetes-induced hyperglycemia impairs male reproductive function: a systematic review.

PubMed

Maresch, Constanze C; Stute, Dina C; Alves, Marco G; Oliveira, Pedro F; de Kretser, David M; Linn, Thomas

2018-01-01

Hyperglycemia can result from a loss of pancreatic beta-cells or a decline in their function leading to decreased insulin secretion or may arise from insulin resistance and variable degrees of inadequate insulin secretion resulting in diabetes and related comorbidities. To date several reviews have addressed the issue of diabetes-related male infertility but most have focused on how metabolic syndrome causes the decline in male fertility. However, a comprehensive overview as to how diabetes-induced hyperglycemia impairs male fertility is missing. Impaired regulation of glucose and the resultant hyperglycemia are major threats to the health of individuals in modern societies especially given the rapidly rising prevalence affecting an increasing number of men in their reproductive years. Consequently, diabetes-induced hyperglycemia is likely to contribute to a decline in global birth rates especially in those societies with a high diabetic prevalence. This systematic review addresses and summarizes the impact of hyperglycemia on male reproductive health with a particular emphasis on the molecular mechanisms that influence the testis and other parts of the male reproductive tract. A systematic search of the literature published in the MEDLINE-Pubmed database (http://www.ncbi.nlm.nih.gov/pubmed) and Cochrane Library (http://www.cochranelibrary.com) was performed, as well as hand searching reference lists, from the earliest available online indexing year until May 2017, using diabetes- and male fertility-related keywords in combination with other search phrases relevant to the topic of hyperglycemia. Inclusion criteria were: clinical studies on type 1 diabetic (T1D) men and studies on T1D animal models with a focus on reproductive parameters. Case reports/series, observational studies and clinical trials were included. Studies on patients with type 2 diabetes (T2D) or animal models of T2D were excluded to distinguish hyperglycemia from other metabolic effects. A total

Aging and male reproductive function: a mitochondrial perspective.

PubMed

Amaral, Sandra; Amaral, Alexandra; Ramalho-Santos, Joao

2013-01-01

Researching the effects of aging in the male reproductive system is not trivial. Not only are multiple changes at molecular, cellular and endocrine levels involved, but any findings must be discussed with variable individual characteristics, as well as with lifestyle and environmental factors. Age-related changes in the reproductive system include any aspect of reproductive function, from deregulation of the hypothalamic-pituitary-gonadal axis and of local auto/paracrine interactions, to effects on testicular stem cells, defects in testicular architecture and spermatogenesis, or sperm with decreased functionality. Several theories place mitochondria at the hub of cellular events related to aging, namely regarding the accumulation of oxidative damage to cells and tissues, a process in which these organelles play a prominent role, although alternative theories have also emerged. However, oxidative stress is not the only process involved in mitochondrial-related aging; mitochondrial energy metabolism, changes in mitochondrial DNA or in mitochondrial-dependent testosterone production are also important. Crucially, all these issues are likely interdependent. We will review evidence that suggests that mitochondria constitute a common link between aging and fertility loss.

The role of the leptin in reproduction.

PubMed

Cervero, Ana; Domínguez, Francisco; Horcajadas, José A; Quiñonero, Alicia; Pellicer, Antonio; Simón, Carlos

2006-06-01

Since its discovery in 1994, leptin has appeared to be a pleiotrophic hormone, governing energy homeostasis and affecting many tissues in the body. Numerous pieces of evidence have accumulated showing that leptin potentially plays an important role in the control of the reproductive function. This review presents the major concepts for the role of leptin in the modulation of reproductive function. As a marker of the nutritional status, leptin affects the hypothalamo-pituitary-gonadal axis, regulating gonadotrophin-releasing hormone and luteinising hormone secretion, and appears to be a permissive factor in the onset of the puberty. This protein and its receptor have been found in the reproductive tissues, indicating that this system could be also implicated in several processes such as embryo development, implantation and pregnancy. Moreover, disorders of the leptin system have been related to some reproductive pathologies such as pre-eclampsia and polycystic ovary syndrome. However, controversy surrounds several aspects of the action of leptin in reproduction that require a deeper investigation of this system. Results to date suggest that this system could be implicated in important reproductive processes such as embryonic development and implantation. Moreover, understanding the role of leptin might be useful for new treatments in reproductive pathologies.

Women's Sexual Health and Reproductive Function After SCI.

PubMed

Courtois, Frédérique; Alexander, Marcalee; McLain, Amie B Jackson

2017-01-01

Sexual function and to a lesser extent reproduction are often disrupted in women with spinal cord injuries (SCI), who must be educated to better understand their sexual and reproductive health. Women with SCI are sexually active; they can use psychogenic or reflexogenic stimulation to obtain sexual pleasure and orgasm. Treatment should consider a holistic approach using autonomic standards to describe remaining sexual function and to assess both genital function and psychosocial factors. Assessment of genital function should include thoracolumbar dermatomes, vulvar sensitivity (touch, pressure, vibration), and sacral reflexes. Self-exploration should include not only clitoral stimulation, but also stimulation of the vagina (G spot), cervix, and nipples conveyed by different innervation sources. Treatments may consider PDE5 inhibitors and flibanserin on an individual basis, and secondary consequences of SCI should address concerns with spasticity, pain, incontinence, and side effects of medications. Psychosocial issues must be addressed as possible contributors to sexual dysfunctions (eg, lower self-esteem, past sexual history, depression, dating habits). Pregnancy is possible for women with SCI; younger age at the time of injury and at the time of pregnancy being significant predictors of successful pregnancy, along with marital status, motor score, mobility, and occupational scores. Pregnancy may decrease the level of functioning (eg, self-care, ambulation, upper-extremity tasks), may involve complications (eg, decubitus ulcers, weight gain, urological complications), and must be monitored for postural hypotension and autonomic dysreflexia. Taking into consideration the physical and psychosocial determinants of sexuality and childbearing allows women with SCI to achieve positive sexual and reproductive health.

Women's Sexual Health and Reproductive Function After SCI

PubMed Central

Alexander, Marcalee; McLain, Amie B. (Jackson)

2017-01-01

Sexual function and to a lesser extent reproduction are often disrupted in women with spinal cord injuries (SCI), who must be educated to better understand their sexual and reproductive health. Women with SCI are sexually active; they can use psychogenic or reflexogenic stimulation to obtain sexual pleasure and orgasm. Treatment should consider a holistic approach using autonomic standards to describe remaining sexual function and to assess both genital function and psychosocial factors. Assessment of genital function should include thoracolumbar dermatomes, vulvar sensitivity (touch, pressure, vibration), and sacral reflexes. Self-exploration should include not only clitoral stimulation, but also stimulation of the vagina (G spot), cervix, and nipples conveyed by different innervation sources. Treatments may consider PDE5 inhibitors and flibanserin on an individual basis, and secondary consequences of SCI should address concerns with spasticity, pain, incontinence, and side effects of medications. Psychosocial issues must be addressed as possible contributors to sexual dysfunctions (eg, lower self-esteem, past sexual history, depression, dating habits). Pregnancy is possible for women with SCI; younger age at the time of injury and at the time of pregnancy being significant predictors of successful pregnancy, along with marital status, motor score, mobility, and occupational scores. Pregnancy may decrease the level of functioning (eg, self-care, ambulation, upper-extremity tasks), may involve complications (eg, decubitus ulcers, weight gain, urological complications), and must be monitored for postural hypotension and autonomic dysreflexia. Taking into consideration the physical and psychosocial determinants of sexuality and childbearing allows women with SCI to achieve positive sexual and reproductive health. PMID:29339874

Demographic and obstetric factors affecting women's sexual functioning during pregnancy.

PubMed

Abouzari-Gazafroodi, Kobra; Najafi, Fatemeh; Kazemnejad, Ehsan; Rahnama, Parvin; Montazeri, Ali

2015-08-19

Sexual desire and frequency of sexual relationships during pregnancy remains challenging. This study aimed to assess factors that affect women's sexual functioning during pregnancy. This was a cross sectional study carried out at prenatal care clinics of public health services in Iran. An author-designed structured questionnaire including items on socio-demographic characteristics, obstetric history, the current pregnancy, and women's sexual functioning during pregnancy was used to collect data. The generalized linear model was performed in order to find out factors that affect women's sexual functioning during pregnancy. In all, 518 pregnant women participated in the study. The mean age of participants was 26.4 years (SD = 4.7). Overall 309 women (59.7%) scored less than mean on sexual functioning. The results obtained from generalized linear model demonstrated that that lower education, unwanted pregnancy, earlier stage of pregnancy, older age, and longer duration of marriage were the most important factors contributing to disturbed sexual functioning among couples. The findings suggest that sexual function during pregnancy might be disturbed due to several factors. Indeed issues on sexual relationship should be included as part of prenatal care and reproductive health programs for every woman.

Reproductive allocation in plants as affected by elevated carbon dioxide and other environmental changes: a synthesis using meta-analysis and graphical vector analysis.

PubMed

Wang, Xianzhong; Taub, Daniel R; Jablonski, Leanne M

2015-04-01

Reproduction is an important life history trait that strongly affects dynamics of plant populations. Although it has been well documented that elevated carbon dioxide (CO2) in the atmosphere greatly enhances biomass production in plants, the overall effect of elevated CO2 on reproductive allocation (RA), i.e., the proportion of biomass allocated to reproductive structures, is little understood. We combined meta-analysis with graphical vector analysis to examine the overall effect of elevated CO2 on RA and how other environmental factors, such as low nutrients, drought and elevated atmospheric ozone (O3), interacted with elevated CO2 in affecting RA in herbaceous plants. Averaged across all species of different functional groups and environmental conditions, elevated CO2 had little effect on RA (-0.9%). RA in plants of different reproductive strategies and functional groups, however, differed in response to elevated CO2. For example, RA in iteroparous wild species decreased by 8%, while RA in iteroparous crops increased significantly (+14%) at elevated CO2. RA was unaffected by CO2 in plants grown with no stress or in low-nutrient soils. RA decreased at elevated CO2 and elevated O3, but increased in response to elevated CO2 in drought-stressed plants, suggesting that elevated CO2 could ameliorate the adverse effect of drought on crop production to some extent. Our results demonstrate that elevated CO2 and other global environmental changes have the potential to greatly alter plant community composition through differential effects on RA of different plant species and thus affect the dynamics of natural and agricultural ecosystems in the future.

Antidiabetic therapies and male reproductive function: where do we stand?

PubMed

Tavares, R S; Escada-Rebelo, S; Silva, A F; Sousa, M I; Ramalho-Santos, J; Amaral, S

2018-01-01

Diabetes mellitus has been increasing at alarming rates in recent years, thus jeopardizing human health worldwide. Several antidiabetic drugs have been introduced in the market to manage glycemic levels, and proven effective in avoiding, minimizing or preventing the appearance or development of diabetes mellitus-related complications. However, and despite the established association between such pathology and male reproductive dysfunction, the influence of these therapeutic interventions on such topics have been scarcely explored. Importantly, this pathology may contribute toward the global decline in male fertility, giving the increasing preponderance of diabetes mellitus in young men at their reproductive age. Therefore, it is mandatory that the reproductive health of diabetic individuals is maintained during the antidiabetic treatment. With this in mind, we have gathered the available information and made a critical analysis regarding the effects of several antidiabetic drugs on male reproductive function. Unlike insulin, which has a clear and fundamental role on male reproductive function, the other antidiabetic therapies' effects at this level seem incoherent. In fact, studies are highly controversial possibly due to the different experimental study approaches, which, in our opinion, suggests caution when it comes to prescribing such drugs to young diabetic patients. Overall, much is still to be determined and further studies are needed to clarify the safety of these antidiabetic strategies on male reproductive system. Aspects such as the effects of insulin levels variations, consequent of insulin therapy, as well as what will be the impact of the side effect hypoglycemia, common to several therapeutic strategies discussed, on the male reproductive system are still to be addressed. © 2018 Society for Reproduction and Fertility.

Facultative symbiont infections affect aphid reproduction.

PubMed

Simon, Jean-Christophe; Boutin, Sébastien; Tsuchida, Tsutomu; Koga, Ryuichi; Le Gallic, Jean-François; Frantz, Adrien; Outreman, Yannick; Fukatsu, Takema

2011-01-01

Some bacterial symbionts alter their hosts reproduction through various mechanisms that enhance their transmission in the host population. In addition to its obligatory symbiont Buchnera aphidicola, the pea aphid Acyrthosiphon pisum harbors several facultative symbionts influencing several aspects of host ecology. Aphids reproduce by cyclical parthenogenesis whereby clonal and sexual reproduction alternate within the annual life cycle. Many species, including the pea aphid, also show variation in their reproductive mode at the population level, with some lineages reproducing by cyclical parthenogenesis and others by permanent parthenogenesis. While the role of facultative symbionts has been well studied during the parthenogenetic phase of their aphid hosts, very little is known on their possible influence during the sexual phase. Here we investigated whether facultative symbionts modulate the capacity to produce sexual forms in various genetic backgrounds of the pea aphid with controlled symbiont composition and also in different aphid genotypes from natural populations with previously characterized infection status and reproductive mode. We found that most facultative symbionts exhibited detrimental effects on their hosts fitness under sex-inducing conditions in comparison with the reference lines. We also showed that the loss of sexual phase in permanently parthenogenetic lineages of A. pisum was not explained by facultative symbionts. Finally, we demonstrated that Spiroplasma infection annihilated the production of males in the host progeny by inducing a male-killing phenotype, an unexpected result for organisms such as aphids that reproduce primarily through clonal reproduction.

Sex Allocation and Reproductive Success in the Andromonoecious Perennial Solanum carolinense (Solanaceae). II. Paternity and Functional Gender.

PubMed

Elle, Elizabeth; Meagher, Thomas R

2000-12-01

According to Bateman's principle, male fitness in entomophilous plant species should be limited by mating opportunity, which is influenced by the size or number of flowers. We determined male-specific fitness consequences of floral phenotype in andromonoecious Solanum carolinense, examined the relationship between male and female reproductive success within plants, and evaluated the distribution of functional gender among plants. A maximum likelihood-based paternity analysis, based on multilocus allozyme phenotypes of parents and offspring from four experimental plots, was used to determine male reproductive success and its relationship to floral phenotype. Male success was enhanced by an increase in the proportion of male flowers produced but not by an increase in total flower number, even though all flowers contain male parts. Larger flower size increased male success in only one plot. Male and female reproductive success were negatively correlated, and plants varied in functional gender from completely female to completely male. This gender specialization may occur because hermaphroditic and male flowers differ in their ability to contribute to male and female success. Although sex allocation theory predicts a positive relationship between the size or number of plant parts and reproductive success, this study indicates that aspects of floral morphology that affect gender specialization should also be considered.

DOFT and DOFTIP1 affect reproductive development in the orchid Dendrobium Chao Praya Smile.

PubMed

Wang, Yanwen; Liu, Lu; Song, Shiyong; Li, Yan; Shen, Lisha; Yu, Hao

2017-12-16

FLOWERING LOCUS T (FT) in Arabidopsis encodes the florigen that moves from leaves to the shoot apical meristem to induce flowering, and this is partly mediated by FT-INTERACTING PROTEIN 1 (FTIP1). Although FT orthologs have been identified in some flowering plants, their endogenous roles in Orchidaceae, which is one of the largest families of flowering plants, are still largely unknown. In this study, we show that DOFT and DOFTIP1, the orchid orthologs of FT and FTIP1, respectively, play important roles in promoting flowering in the orchid Dendrobium Chao Praya Smile. Expression of DOFT and DOFTIP1 increases in whole plantlets during the transition from vegetative to reproductive development. Both transcripts are present in significant levels in reproductive organs, including inflorescence apices, stems, floral buds, and open flowers. Through successful generation of transgenic orchids, we have revealed that overexpression or down-regulation of DOFT accelerates or delays flowering, respectively, while alteration of DOFT expression also greatly affects pseudobulb formation and flower development. In common with their counterparts in Arabidopsis and rice, DOFTIP1 interacts with DOFT and affects flowering time in orchids. Our results suggest that while DOFT and DOFTIP1 play evolutionarily conserved roles in promoting flowering, DOFT may have evolved with hitherto unknown functions pertaining to the regulation of storage organs and flower development in the Orchidaceae family. © The Author 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology.

Evolution and functional divergence of NLRP genes in mammalian reproductive systems

PubMed Central

2009-01-01

Background NLRPs (Nucleotide-binding oligomerization domain, Leucine rich Repeat and Pyrin domain containing Proteins) are members of NLR (Nod-like receptors) protein family. Recent researches have shown that NLRP genes play important roles in both mammalian innate immune system and reproductive system. Several of NLRP genes were shown to be specifically expressed in the oocyte in mammals. The aim of the present work was to study how these genes evolved and diverged after their duplication, as well as whether natural selection played a role during their evolution. Results By using in silico methods, we have evaluated the evolution and functional divergence of NLRP genes, in particular of mouse reproduction-related Nlrp genes. We found that (1) major NLRP genes have been duplicated before the divergence of mammals, with certain lineage-specific duplications in primates (NLRP7 and 11) and in rodents (Nlrp1, 4 and 9 duplicates); (2) tandem duplication events gave rise to a mammalian reproduction-related NLRP cluster including NLRP2, 4, 5, 7, 8, 9, 11, 13 and 14 genes; (3) the function of mammalian oocyte-specific NLRP genes (NLRP4, 5, 9 and 14) might have diverged during gene evolution; (4) recent segmental duplications concerning Nlrp4 copies and vomeronasal 1 receptor encoding genes (V1r) have been undertaken in the mouse; and (5) duplicates of Nlrp4 and 9 in the mouse might have been subjected to adaptive evolution. Conclusion In conclusion, this study brings us novel information on the evolution of mammalian reproduction-related NLRPs. On the one hand, NLRP genes duplicated and functionally diversified in mammalian reproductive systems (such as NLRP4, 5, 9 and 14). On the other hand, during evolution, different lineages adapted to develop their own NLRP genes, particularly in reproductive function (such as the specific expansion of Nlrp4 and Nlrp9 in the mouse). PMID:19682372

Reproductive health policy affecting low-income women: historical precedents and current need for social work action.

PubMed

Averitt Taylor, Jessica

2014-01-01

This article provides an overview of the historical arguments surrounding reproductive health policy and current policy initiatives. Because reproductive policy itself is a vast subject matter with sometimes blurry boundaries, the struggle concerning the advent of birth control is used to illustrate the historic complexities of policy affecting such a wide array of individuals. The battle over introduction of the birth control pill is pertinent because the very same arguments are used today in debates over reproductive health policy.

The value of eutherian-marsupial comparisons for understanding the function of glucocorticoids in female mammal reproduction.

PubMed

Fanson, Kerry V; Parrott, Marissa L

2015-11-01

This article is part of a Special Issue "SBN 2014". Chronic stress is known to inhibit female reproductive function. Consequently, it is often assumed that glucocorticoid (GC) concentrations should be negatively correlated with reproductive success because of the role they play in stress physiology. In contrast, a growing body of evidence indicates that GCs play an active role in promoting reproductive function. It is precisely because GCs are so integral to the entire process that disruptions to adrenal activity have negative consequences for reproduction. The goal of this paper is to draw attention to the increasing evidence showing that increases in adrenal activity are important for healthy female reproduction. Furthermore, we outline several hypotheses about the functional role(s) that GCs may play in mediating reproduction and argue that comparative studies between eutherian and marsupial mammals, which exhibit some pronounced differences in reproductive physiology, may be particularly useful for testing different hypotheses about the functional role of GCs in reproduction. Much of our current thinking about GCs and reproduction comes from research involving stress-induced levels of GCs and has led to broad assumptions about the effects of GCs on reproduction. Unfortunately, this has left a gaping hole in our knowledge about basal GC levels and how they may influence reproductive function, thereby preventing a broader understanding of adrenal physiology and obscuring potential solutions for reproductive dysfunction. Copyright © 2015 Elsevier Inc. All rights reserved.

Potential negative effects of anti-histamines on male reproductive function.

PubMed

Mondillo, Carolina; Varela, María Luisa; Abiuso, Adriana María Belén; Vázquez, Ramiro

2018-05-01

Histamine (HA) is a pleiotropic biogenic amine synthesized exclusively by histidine decarboxylase (HDC) in most mammalian tissues. The literature on the role of HA within the male gonad has expanded over the last years, attracting attention to potential unexpected side-effects of anti-histamines on testicular function. In this regard, HA receptors (HRH1, HRH2 and HRH4) have been described in Leydig cells of different species, including human. Via these receptors, HA has been reported to trigger positive or negative interactions with the LH/hCG signaling pathway depending upon its concentration, thereby contributing to the local control of testicular androgen levels. It should then be considered that anti-histamines may affect testicular homeostasis by increasing or decreasing steroid production. Additionally, HRH1 and HRH2 receptors are present in peritubular and germ cells, and HRH2 antagonists have been found to negatively affect peritubular cells and reduce sperm viability. The potential negative impact of anti-histamines on male reproduction becomes even more dramatic if we consider that HA has also been associated with human sexual behavior and penile erection. What is more, although testicular mast cells are the major source of locally produced HA, recent studies have described HDC expression in macrophages, Leydig cells and germ cells, revealing the existence of multiple sources of HA within the testis. Undoubtedly, the more we learn about the testicular histaminergic system, the more opportunities there will be for rational design of drugs aimed at treating HA-related pathologies, with minimum or nule negative impact on fertility. © 2018 Society for Reproduction and Fertility.

Impairment of male reproductive function after sleep deprivation.

PubMed

Alvarenga, Tathiana A; Hirotsu, Camila; Mazaro-Costa, Renata; Tufik, Sergio; Andersen, Monica L

2015-05-01

To evaluate the influence of sleep loss on sexual behavior, hormone levels, sperm parameters, and testis-specific gene expression in male rats. Experimental research. Animal laboratory. Male adult Wistar-Hannover rats. Sexually experienced rats were subjected to paradoxic sleep deprivation (PSD) for 96 hours or sleep restriction (SR) for 21 days or kept in their home cage as control (CTRL). Sexual behavior, hormone levels, sperm parameters and expression of stress and nitric oxide-related genes were evaluated. PSD significantly decreased sexual behavior compared with the CTRL group, whereas SR had no effect. The PSD group had significantly lower testosterone levels than the CTRL group. Both PSD and SR groups had lower sperm viabilities than the CTRL group. The decrease in the number of live sperm compared with the CTRL group was larger in the PSD group than in the SR group. Regarding testicular gene expression, both PSD and SR led to an increase of iNOS and hydroxysteroid 11β-dehydrogenase 1 expressions compared with the CTRL group. These changes were more pronounced in the PSD group. A significant increase in endothelial nitric oxide synthase expression was observed in the PSD groups compared with the CTRL group. No changes were observed in dimethylarginine dimethylaminohydrolase 1 and casein kinase 2β-polypeptide expressions. Sleep loss can promote marked changes in the male reproductive system of rats, particularly affecting spermatic function in part by interfering in the testicular nitric oxide pathway. Copyright © 2015 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

Predation risk affects reproductive physiology and demography of elk.

PubMed

Creel, Scott; Christianson, David; Liley, Stewart; Winnie, John A

2007-02-16

Elk (Cervus elaphus) in the Greater Yellowstone Ecosystem alter patterns of aggregation, habitat selection, vigilance, and foraging in the presence of wolves (Canis lupus). Antipredator behaviors like these can reduce predation risk but are also likely to carry costs. Data from five elk populations studied for 16 site years showed that progesterone concentrations (from 1489 fecal samples) declined with the ratio of elk to wolves. In turn, progesterone concentrations were a good predictor of calf recruitment in the subsequent year. Together, these data suggest that wolves indirectly affect the reproductive physiology and the demography of elk through the costs of antipredator behavior.

[Osteopontin and male reproduction].

PubMed

Liu, Qian; Xie, Qing-Zhen

2012-05-01

Osteopontin (OPN) is an extracellular matrix protein with multifunctions, expressed in various tissues and body fluids, involved in various physiological and pathological processes. It is also detected in the reproductive tract of both males and females, and participates in the implantation, development and differentiation of embryos. Recent studies have indicated that OPN is closely related with male fertility and may affect sperm quality and fertilization. An insight into the functions of OPN may help to explain the mechanisms of male infertility and improve the success rate of assisted reproductive technology.

Beadex Function in the Motor Neurons Is Essential for Female Reproduction in Drosophila melanogaster

PubMed Central

Kairamkonda, Subhash; Nongthomba, Upendra

2014-01-01

Drosophila melanogaster has served as an excellent model system for understanding the neuronal circuits and molecular mechanisms regulating complex behaviors. The Drosophila female reproductive circuits, in particular, are well studied and can be used as a tool to understand the role of novel genes in neuronal function in general and female reproduction in particular. In the present study, the role of Beadex, a transcription co-activator, in Drosophila female reproduction was assessed by generation of mutant and knock down studies. Null allele of Beadex was generated by transposase induced excision of P-element present within an intron of Beadex gene. The mutant showed highly compromised reproductive abilities as evaluated by reduced fecundity and fertility, abnormal oviposition and more importantly, the failure of sperm release from storage organs. However, no defect was found in the overall ovariole development. Tissue specific, targeted knock down of Beadex indicated that its function in neurons is important for efficient female reproduction, since its neuronal knock down led to compromised female reproductive abilities, similar to Beadex null females. Further, different neuronal class specific knock down studies revealed that Beadex function is required in motor neurons for normal fecundity and fertility of females. Thus, the present study attributes a novel and essential role for Beadex in female reproduction through neurons. PMID:25396431

Genetic and environmental origins of obesity relevant to reproduction.

PubMed

Franks, Stephen

2006-05-01

Obesity has a negative impact on reproductive health, particularly in women with polycystic ovarian syndrome (PCOS). Obesity itself is the product of both genetic and environmental influences, although the current 'epidemic' of obesity is largely related to changes in diet and lifestyle. Single gene defects leading to obesity and disordered reproductive function are rare but can are informative about metabolic pathways involved in appetite regulation. There is good evidence that PCOS has an important genetic background, which probably involves the interaction of several genes. The phenotype of PCOS and its impact on reproductive function is profoundly affected by obesity, which, in turn has both genetic and environmental influences. Understanding the genetic basis of PCOS is important but improvements in diet and lifestyle are the best means of improving reproductive function.

Removal of the local geomagnetic field affects reproductive growth in Arabidopsis.

PubMed

Xu, Chunxiao; Wei, Shufeng; Lu, Yan; Zhang, Yuxia; Chen, Chuanfang; Song, Tao

2013-09-01

The influence of the geomagnetic field-removed environment on Arabidopsis growth was investigated by cultivation of the plants in a near-null magnetic field and local geomagnetic field (45 µT) for the whole growth period under laboratory conditions. The biomass accumulation of plants in the near-null magnetic field was significantly suppressed at the time when plants were switching from vegetative growth to reproductive growth compared with that of plants grown in the local geomagnetic field, which was caused by a delay in the flowering of plants in the near-null magnetic field. At the early or later growth stage, no significant difference was shown in the biomass accumulation between the plants in the near-null magnetic field and local geomagnetic field. The average number of siliques and the production of seeds per plant in the near-null magnetic field was significantly lower by about 22% and 19%, respectively, than those of control plants. These resulted in a significant reduction of about 20% in the harvest index of plants in the near-null magnetic field compared with that of the controls. These results suggest that the removal of the local geomagnetic field negatively affects the reproductive growth of Arabidopsis, which thus affects the yield and harvest index. Copyright © 2013 Wiley Periodicals, Inc.

Novel function of LHFPL2 in female and male distal reproductive tract development.

PubMed

Zhao, Fei; Zhou, Jun; Li, Rong; Dudley, Elizabeth A; Ye, Xiaoqin

2016-03-11

Congenital reproductive tract anomalies could impair fertility. Female and male reproductive tracts are developed from Müllerian ducts and Wolffian ducts, respectively, involving initiation, elongation and differentiation. Genetic basis solely for distal reproductive tract development is largely unknown. Lhfpl2 (lipoma HMGIC fusion partner-like 2) encodes a tetra-transmembrane protein with unknown functions. It is expressed in follicle cells of ovary and epithelial cells of reproductive tracts. A spontaneous point mutation of Lhfpl2 (LHFPL2(G102E)) leads to infertility in 100% female mice, which have normal ovarian development, ovulation, uterine development, and uterine response to exogenous estrogen stimulation, but abnormal upper longitudinal vaginal septum and lower vaginal agenesis. Infertility is also observed in ~70% mutant males, which have normal mating behavior and sperm counts, but abnormal distal vas deferens convolution resulting in complete and incomplete blockage of reproductive tract in infertile and fertile males, respectively. On embryonic day 15.5, mutant Müllerian ducts and Wolffian ducts have elongated but their duct tips are enlarged and fail to merge with the urogenital sinus. These findings provide a novel function of LHFPL2 and a novel genetic basis for distal reproductive tract development; they also emphasize the importance of an additional merging phase for proper reproductive tract development.

Interactions between prolactin and kisspeptin to control reproduction.

PubMed

Donato, Jose; Frazão, Renata

2016-01-01

Prolactin is best known for its effects of stimulating mammary gland development and lactogenesis. However, prolactin is a pleiotropic hormone that is able to affect several physiological functions, including fertility. Prolactin receptors (PRLRs) are widely expressed in several tissues, including several brain regions and reproductive tract organs. Upon activation, PRLRs may exert prolactin's functions through several signaling pathways, although the recruitment of the signal transducer and activator of transcription 5 causes most of the known effects of prolactin. Pathological hyperprolactinemia is mainly due to the presence of a prolactinoma or pharmacological effects induced by drugs that interact with the dopamine system. Notably, hyperprolactinemia is a frequent cause of reproductive dysfunction and may lead to infertility in males and females. Recently, several studies have indicated that prolactin may modulate the reproductive axis by acting on specific populations of hypothalamic neurons that express the Kiss1 gene. The Kiss1 gene encodes neuropeptides known as kisspeptins, which are powerful activators of gonadotropin-releasing hormone neurons. In the present review, we will summarize the current knowledge about prolactin's actions on reproduction. Among other aspects, we will discuss whether the interaction between prolactin and the Kiss1-expressing neurons can affect reproduction and how kisspeptins may become a novel therapeutic approach to treat prolactin-induced infertility.

Mastitis effects on reproductive performance in dairy cattle: a review.

PubMed

Kumar, Narender; Manimaran, A; Kumaresan, A; Jeyakumar, S; Sreela, L; Mooventhan, P; Sivaram, M

2017-04-01

The reproductive performance of dairy animals is influenced by several factors, and accumulating lines of evidence indicate that mastitis is one of the determinants. Most of the published information relating mastitis with reproduction has evolved based on retrospective approach rather than controlled clinical studies. The complex nature of both mastitis and reproduction could be a limiting factor for understanding their relationship in detail. In this review, we analyzed the available retrospective studies on the effects of clinical mastitis on reproductive function and explained the possible mechanisms by which mastitis affects reproduction in dairy animals.

Sodium fluoride adversely affects ovarian development and reproduction in Drosophila melanogaster.

PubMed

Khatun, Salma; Rajak, Prem; Dutta, Moumita; Roy, Sumedha

2017-11-01

The study demonstrates the effects of chronic sub-lethal exposure of sodium fluoride (NaF) on reproductive structure and function of female Drosophila melanogaster. As a part of treatment, flies were maintained in food supplemented with sub-lethal concentrations of NaF (10-100 μg/mL). Fecundity, ovarian morphology, presence and profusion of viable cells from ovary and fat body were taken into consideration for evaluating changes in reproductive homeostasis. Wing length (a factor demonstrating body size and reproductive fitness) was also monitored after NaF exposure. Significant reduction in fecundity, alteration in ovarian morphology along with an increase in apoptosis was observed in treated females. Simultaneous decline in viable cell number and larval weight validates the result of MTT assay. Furthermore, altered ovarian Glucose-6-phosphate dehydrogenase and catalase activities together with increased rate of lipid peroxidation after 20 and 40 μg/mL NaF exposure confirmed the changes in reproduction related metabolism. Enhanced lipid peroxidation known for ROS generation might have induced genotoxicity which is confirmed through Comet assay. The enzyme activities were not dose dependent, rather manifested a bimodal response, which suggests a well-knit interaction among the players inducing stress and the ones that help establish physiological homeostasis. Copyright © 2017 Elsevier Ltd. All rights reserved.

Functional study of Cordyceps sinensis and cordycepin in male reproduction: A review.

PubMed

Chen, Yung-Chia; Chen, Ying-Hui; Pan, Bo-Syong; Chang, Ming-Min; Huang, Bu-Miin

2017-01-01

Cordyceps sinensis has various biological and pharmacological functions, and it has been claimed as a tonic supplement for sexual and reproductive dysfunctions for a long time in oriental society. In this article, the in vitro and in vivo effects of C. sinensis and cordycepin on mouse Leydig cell steroidogenesis are briefly described, the stimulatory mechanisms are summarized, and the recent findings related to the alternative substances regulating male reproductive functions are also discussed. Copyright © 2016. Published by Elsevier B.V.

Circadian rhythms and reproduction.

PubMed

Boden, Michael J; Kennaway, David J

2006-09-01

There is a growing recognition that the circadian timing system, in particular recently discovered clock genes, plays a major role in a wide range of physiological systems. Microarray studies, for example, have shown that the expression of hundreds of genes changes many fold in the suprachiasmatic nucleus, liver heart and kidney. In this review, we discuss the role of circadian rhythmicity in the control of reproductive function in animals and humans. Circadian rhythms and clock genes appear to be involved in optimal reproductive performance, but there are sufficient redundancies in their function that many of the knockout mice produced do not show overt reproductive failure. Furthermore, important strain differences have emerged from the studies especially between the various Clock (Circadian Locomotor Output Cycle Kaput) mutant strains. Nevertheless, there is emerging evidence that the primary clock genes, Clock and Bmal1 (Brain and Muscle ARNT-like protein 1, also known as Mop3), strongly influence reproductive competency. The extent to which the circadian timing system affects human reproductive performance is not known, in part, because many of the appropriate studies have not been done. With the role of Clock and Bmal1 in fertility becoming clearer, it may be time to pursue the effect of polymorphisms in these genes in relation to the various types of infertility in humans.

Perceived Risk of Predation Affects Reproductive Life-History Traits in Gambusia holbrooki, but Not in Heterandria formosa

PubMed Central

Mukherjee, Shomen; Heithaus, Michael R.; Trexler, Joel C.; Ray-Mukherjee, Jayanti; Vaudo, Jeremy

2014-01-01

Key to predicting impacts of predation is understanding the mechanisms through which predators impact prey populations. While consumptive effects are well-known, non-consumptive predator effects (risk effects) are increasingly being recognized as important. Studies of risk effects, however, have focused largely on how trade-offs between food and safety affect fitness. Less documented, and appreciated, is the potential for predator presence to directly suppress prey reproduction and affect life-history characteristics. For the first time, we tested the effects of visual predator cues on reproduction of two prey species with different reproductive modes, lecithotrophy (i.e. embryonic development primarily fueled by yolk) and matrotrophy (i.e. energy for embryonic development directly supplied by the mother to the embryo through a vascular connection). Predation risk suppressed reproduction in the lecithotrophic prey (Gambusia holbrokii) but not the matrotroph (Heterandria formosa). Predator stress caused G. holbrooki to reduce clutch size by 43%, and to produce larger and heavier offspring compared to control females. H. formosa, however, did not show any such difference. In G. holbrooki we also found a significantly high percentage (14%) of stillbirths in predator-exposed treatments compared to controls (2%). To the best of our knowledge, this is the first direct empirical evidence of predation stress affecting stillbirths in prey. Our results suggest that matrotrophy, superfetation (clutch overlap), or both decrease the sensitivity of mothers to environmental fluctuation in resource (food) and stress (predation risk) levels compared to lecithotrophy. These mechanisms should be considered both when modeling consequences of perceived risk of predation on prey-predator population dynamics and when seeking to understand the evolution of reproductive modes. PMID:24551171

Vitamin D metabolism, sex hormones, and male reproductive function.

PubMed

Blomberg Jensen, Martin

2012-08-01

The spectrum of vitamin D (VD)-mediated effects has expanded in recent years, and VD is now recognized as a versatile signaling molecule rather than being solely a regulator of bone health and calcium homeostasis. One of the recently identified target areas of VD is male reproductive function. The VD receptor (VDR) and the VD metabolizing enzyme expression studies documented the presence of this system in the testes, mature spermatozoa, and ejaculatory tract, suggesting that both systemic and local VD metabolism may influence male reproductive function. However, it is still debated which cell is the main VD target in the testis and to what extent VD is important for sex hormone production and function of spermatozoa. This review summarizes descriptive studies on testicular VD metabolism and spatial distribution of VDR and the VD metabolizing enzymes in the mammalian testes and discusses mechanistic and association studies conducted in animals and humans. The reviewed evidence suggests some effects of VD on estrogen and testosterone biosynthesis and implicates involvement of both systemic and local VD metabolism in the regulation of male fertility potential.

Heat stress affects male reproduction in a parasitoid wasp.

PubMed

Nguyen, Thanh Manh; Bressac, Christophe; Chevrier, Claude

2013-03-01

In insects, reproductive success and survival are affected by temperature. Reproduction is more sensitive than other physiological traits. While the effects of heat stress on females are well known, the effects on males are less clear. Hymenopteran parasitoids are valuable for studying the consequences of heat stress on male reproduction. In these species, through arrhenotoquous parthenogenesis, the sex ratio of the offspring is directly dependent on the sperm stock acquired by females during copulation. In the lab, heat temperature treatments (32-44°C) were applied for 3 days in the pupal stage of Anisopteromalus calandrae males, and development was completed at 30°C. Three different effects were observed depending on the temperature: mortality above 42°C, sterility of emerging males at 40°C, and sub-fertility at 38°C. This sub-fertility is characterized by a dramatic decrease in male sperm supplies, of up to 7% compared to control males. In the course of ageing, the sperm stock of sub-fertile males increases but never reaches the level of control males. Survival was significantly higher in control (30°C) males than those treated at 38°C. Male mating ability was similar whatever the treatment (control and 38°C), but females mated with 38°C-treated males stored 100 times less sperm on average than those mated with control males. The offspring sex ratio of females mated with 38°C-treated males was strongly male biased. The physiological mechanisms are as yet unknown. The relationship between temperature, sperm stock and sex ratio should be taken into account in the management of parasitoids for integrated pest management. Copyright © 2012 Elsevier Ltd. All rights reserved.

Energy-containing beverages: reproductive hormones and ovarian function in the BioCycle Study.

PubMed

Schliep, Karen C; Schisterman, Enrique F; Mumford, Sunni L; Pollack, Anna Z; Perkins, Neil J; Ye, Aijun; Zhang, Cuilin J; Stanford, Joseph B; Porucznik, Christina A; Hammoud, Ahmad O; Wactawski-Wende, Jean

2013-03-01

Energy-containing beverages are widely consumed among premenopausal women, but their association with reproductive hormones is not well understood. The objective was to assess the association of energy-containing beverages, added sugars, and total fructose intake with reproductive hormones among ovulatory cycles and sporadic anovulation in healthy premenopausal women. Women (n = 259) in the BioCycle Study were followed for up to 2 menstrual cycles; they provided fasting blood specimens during up to 8 visits/cycle and four 24-h dietary recalls/cycle. Women who consumed ≥1 cup (1 cup = 237 mL) sweetened soda/d had 16.3% higher estradiol concentrations compared with women who consumed less sweetened soda (86.5 pg/mL compared with 74.4 pg/mL, P = 0.01) after adjustment for age, BMI, race, dietary factors, and physical activity. Similarly elevated estradiol concentrations were found for ≥1 cup cola/d and noncola soda intake. Neither artificially sweetened soda nor fruit juice intake ≥1 cup/d was significantly associated with reproductive hormones. Added sugar above the average US woman's intake (≥73.2 g/d) or above the 66th percentile in total fructose intake (≥41.5 g/d) was associated with significantly elevated estradiol but not consistently across all models. No associations were found between beverages, added sugars, or total fructose intake and anovulation after multivariate adjustment. Even at moderate consumption amounts, sweetened soda is associated with elevated follicular estradiol concentrations among premenopausal women but does not appear to affect ovulatory function. Further research into the mechanism driving the association between energy-containing beverages and reproductive hormones, and its potential implications for women's health, is warranted.

The soothing function of touch: affective touch reduces feelings of social exclusion.

PubMed

von Mohr, Mariana; Kirsch, Louise P; Fotopoulou, Aikaterini

2017-10-18

The mammalian need for social proximity, attachment and belonging may have an adaptive and evolutionary value in terms of survival and reproductive success. Consequently, ostracism may induce strong negative feelings of social exclusion. Recent studies suggest that slow, affective touch, which is mediated by a separate, specific C tactile neurophysiological system than faster, neutral touch, modulates the perception of physical pain. However, it remains unknown whether slow, affective touch, can also reduce feelings of social exclusion, a form of social pain. Here, we employed a social exclusion paradigm, namely the Cyberball task (N = 84), to examine whether the administration of slow, affective touch may reduce the negative feelings of ostracism induced by the social exclusion manipulations of the Cyberball task. As predicted, the provision of slow-affective, as compared to fast-neutral, touch led to a specific decrease in feelings of social exclusion, beyond general mood effects. These findings point to the soothing function of slow, affective touch, particularly in the context of social separation or rejection, and suggest a specific relation between affective touch and social bonding.

Reproduction

USDA-ARS?s Scientific Manuscript database

Reproductive efficiency, or percentage of lamb crop raised and marketed, is the major factor affecting profitability of a sheep flock. Frequently, an increased reproductive rate will be the most efficient way to increase income rather than an increase in numbers of ewes. Consequently, increasing th...

The disadvantages of mating outside home: How breeding in captivity affects the reproductive success of seahorses?

NASA Astrophysics Data System (ADS)

Faleiro, Filipa; Narciso, Luís

2013-04-01

In captivity, husbandry conditions are distinct from those experienced by fish in the wild and may have a significant effect on reproductive success. This study evaluates the effect of supportive breeding (i.e., breeding animals in captivity using wild parents) on some quantitative and qualitative aspects of the reproductive success of the long-snouted seahorse, Hippocampus guttulatus. Wild and captive broods were compared in terms of juvenile number, size, condition and fatty acid profile at birth. Reproductive investment and breeding success of H. guttulatus decreased considerably in captivity. Juveniles from captive broods were fewer in number, smaller, generally thinner and with lower fatty acid contents (per juvenile) than those from wild broods, although their fatty acid composition (μg mg- 1 DW or %TFA) was not significantly affected. Although not greatly encouraging, the poor reproductive performance of captive seahorses should not, however, efface the potential of supportive breeding as a tool for seahorse conservation. Enhanced conditions and long-term breeding in captivity will allow to improve the reproductive success of the species and the quality of the fingerlings.

Functional Analysis of Nuclear Estrogen Receptors in Zebrafish Reproduction by Genome Editing Approach.

PubMed

Lu, Huijie; Cui, Yong; Jiang, Liwen; Ge, Wei

2017-07-01

Estrogens signal through both nuclear and membrane receptors with most reported effects being mediated via the nuclear estrogen receptors (nERs). Although much work has been reported on nERs in the zebrafish, there is a lack of direct genetic evidence for their functional roles and importance in reproduction. To address this issue, we undertook this study to disrupt all three nERs in the zebrafish, namely esr1 (ERα), esr2a (ERβII), and esr2b (ERβI), by the genome-editing technology clustered regularly interspaced short palindromic repeats and its associated nuclease (CRISPR/Cas9). Using this loss-of-function genetic approach, we successfully created three mutant zebrafish lines with each nER knocked out. In addition, we also generated all possible double and triple knockouts of the three nERs. The phenotypes of these mutants in reproduction were analyzed in all single, double, and triple nER knockouts in both females and males. Surprisingly, all three single nER mutant fish lines display normal reproductive development and function in both females and males, suggesting functional redundancy among these nERs. Further analysis of double and triple knockouts showed that nERs, especially Esr2a and Esr2b, were essential for female reproduction, and loss of these two nERs led to an arrest of folliculogenesis at previtellogenic stage II followed by sex reversal from female to male. In addition, the current study also revealed a unique role for Esr2a in follicle cell proliferation and transdifferentiation, follicle growth, and chorion formation. Taken together, this study provides the most comprehensive genetic analysis for differential functions of esr1, esr2a, and esr2b in fish reproduction. Copyright © 2017 Endocrine Society.

The long-term effects of the Holocaust on the reproductive function of female survivors.

PubMed

Pasternak, Alfred; Brooks, Philip G

2007-01-01

The aim of this study was to evaluate the effect of internment in the German concentration camps during World War II on menstrual function; future fertility; and, ultimately, on gynecologic diseases or future surgery needs. Five hundred eighty Hungarian female survivors of concentration camps. Menstrual and reproductive histories of the women were obtained and analyzed, comparing histories and events from pre-internment, internment, and post-internment periods of time. The mean age of the survivors at the time of internment was 23.4 +/- 8.0 years (95% CI 22.7-24.1). Amenorrhea occurred in 94.8% of the women during encampment (95% CI 92.7%-96.5%), with 82.4% experiencing cessation of menses immediately after internment (95% CI 76.9%-85.6%). Only 0.6% of women (95% CI 0.12%-1.63%) menstruated longer than 4 months after internment. After liberation, all but 8.9% of the women resumed menstruation within the first year (95% CI 88.4%-93.3%). Fecundity subsequent to liberation was not significantly affected by the imprisonment nor was there a significant increase in spontaneous abortion, ectopic pregnancies, stillbirths, or other pregnancy complications. Additionally, there was no evidence of impact on the subsequent frequency of gynecologic diseases or surgical procedures. Imprisonment in German concentration camps during the Holocaust resulted in enormous emotional and psychological changes in the survivors. In addition, this study reveals abrupt changes in short-term menstrual function but little long-term physical damage to reproductive function.

Effect of dystocia on subsequent reproductive performance and functional longevity in Holstein cows.

PubMed

Ghavi Hossein-Zadeh, N

2016-10-01

The objective of this study was to evaluate the effect of dystocia on the reproductive performance and functional longevity in Iranian Holsteins. Data consisted of 1 467 064 lactation records of 581 421 Holstein cows from 3083 herds which were collected by the Animal Breeding Center of Iran from April 1987 to February 2014. Reproduction traits in this study included interval from first to second calving, days open and days from first calving to first service. The generalized linear model was used for the statistical analysis of reproductive traits. Survival analysis was performed using the Weibull proportional hazards models to analyse the impact of dystocia on functional longevity. The incidence of dystocia had an adverse effect on the reproductive performance of dairy cows. Therefore, reproductive traits deteriorated along with increase in dystocia score (p < 0.05). The culling risk was increased along with increase in the score of dystocia (p < 0.0001). The greatest culling risk was observed in primiparous cows, small herds and low-yielding cows (p < 0.0001). Also, the lowest culling risk was found for cows calving at the youngest age (<27 months), and cows with age at first calving >33 months had the greatest risk (p < 0.0001). The results of current study indicated that dystocia had important negative effects on the reproductive performance and functional longevity in dairy cows, and it should be avoided as much as possible to provide a good perspective in the scope of economic and animal welfare issues in dairy herds. Journal of Animal Physiology and Animal Nutrition © 2016 Blackwell Verlag GmbH.

Altitude affects the reproductive performance in monoicous and dioicous bryophytes: examples from a Brazilian Atlantic rainforest

PubMed Central

Maciel-Silva, Adaíses S.; Marques Valio, Ivany F.; Rydin, Håkan

2012-01-01

Background and aims Short life cycles and trade-offs linked to breeding systems make bryophytes good models for the study of plant reproductive strategies. Our aim was to test if differences in sexual reproductive performance of bryophytes in tropical rainforests are driven by the breeding system of the species (monoicous or dioicous) or are mainly affected by the habitat. Methodology The reproductive performance (sexual branches, gametangia (sex organs), fertilization and sporophyte production) of 11 species was repeatedly monitored and analysed from populations at sea-level and montane sites of a Brazilian Atlantic rainforest over 15 months. Principal results Monoicous species had the highest reproductive performance, particularly for sexual branches, fertilized gametangia and sporophyte production. Species at the sea-level site produced more sexual branches and had more female-biased sex ratios of gametangia than species in the montane site. Fertilizations were more frequent at the montane site, but sporophyte frequency was similar between the two sites. Fertilization tended to occur mostly in the periods of heavy rain (October to December). Conclusions Breeding system is not the only major influence on the reproductive performance of bryophytes. We show that habitat is also an important factor determining life-history differentiation. Female-biased sex ratios and low rates of fertilization are seen to be compensated for by high production of reproductive structures at the initial phases of the reproductive cycle. PMID:22822422

Reproductive partitioning and the assumptions of reproductive skew models in the cooperatively breeding American crow

PubMed Central

Townsend, Andrea K.; Clark, Anne B.; McGowan, Kevin J.; Lovette, Irby J.

2009-01-01

Understanding the benefits of cooperative breeding for group members of different social and demographic classes requires knowledge of their reproductive partitioning and genetic relatedness. From 2004-2007, we examined parentage as a function of relatedness and social interactions among members of 21 American crow (Corvus brachyrhynchos) family groups. Paired female breeders monopolized maternity of all offspring in their broods, whereas paired male breeders sired 82.7% of offspring, within-group auxiliary males sired 6.9% of offspring, and extragroup males sired 10.4% of offspring. Although adult females had fewer opportunities for direct reproduction as auxiliaries than males, they appeared to have earlier opportunities for independent breeding. These different opportunities for direct reproduction probably contributed to the male biased adult auxiliary sex ratio. Patterns of reproductive partitioning and conflict among males were most consistent with a synthetic reproductive skew model, in which auxiliaries struggled with breeders for a limited reproductive share, beyond which breeders could evict them. Counter to a frequent assumption of reproductive skew models, female breeders appeared to influence paternity, although their interests might have agreed with the interests of their paired males. Unusual among cooperative breeders, close inbreeding and incest occurred in this population. Incest avoidance between potential breeders did not significantly affect reproductive skew. PMID:20126287

Impact of Reproductive History and Exogenous Hormone Use on Cognitive Function in Midlife and Late Life

PubMed Central

Karim, Roksana; Dang, Ha; Henderson, Victor W.; Hodis, Howard N.; St John, Jan; Brinton, Roberta D.; Mack, Wendy J.

2016-01-01

Background/objectives Given the potent role of sex hormones on brain chemistry and function, we investigated the association of reproductive history indicators of hormonal exposures, including reproductive period, pregnancy, and use of hormonal contraceptives, on mid- and late-life cognition in postmenopausal women. Design Analysis of baseline data from two randomized clinical trials, the Women’s Isoflavone Soy Health (WISH) and the Early vs Late Intervention Trial of Estradiol (ELITE). Setting University academic research center Participants 830 naturally menopausal women Measurements Participants were uniformly evaluated with a cognitive battery and a structured reproductive history. Outcomes were composite scores for verbal episodic memory, executive functions, and global cognition. Reproductive variables included ages at pregnancies, menarche, and menopause, reproductive period, number of pregnancies, and use of hormones for contraception and menopausal symptoms. Multivariable linear regression evaluated associations between cognitive scores (dependent variable) and reproductive factors (independent variables), adjusting for age, race/ethnicity, income and education. Results On multivariable modeling, age at menarche ≥ 13 years of age was inversely associated with global cognition (p= 0.05). Last pregnancy after age 35 was positively associated with verbal memory (p=0.03). Use of hormonal contraceptives was positively associated with global cognition (p trend=0.04), and verbal memory (p trend=0.007). The association between hormonal contraceptive use and verbal memory and executive functions was strongest for more than 10 years of use. Reproductive period was positively associated with global cognition (p=0.04) and executive functions (p=0.04). Conclusion In this sample of healthy postmenopausal women, reproductive life events related to sex hormones, including earlier age at menarche, later age at last pregnancy, length of reproductive period, and use of

Heme oxygenase/carbon monoxide in the female reproductive system: an overlooked signalling pathway

PubMed Central

Němeček, David; Dvořáková, Markéta; Sedmíková, Markéta

2017-01-01

For a long time, carbon monoxide (CO) was known for its toxic effect on organisms. But there are still many things left to discover on that molecule. CO is formed directly in the body by the enzymatic activity of heme oxygenase (HO). CO plays an important role in many physiological processes, such as cell protections (against various stress factors), and the regulation of metabolic processes. Recent research proves that CO also operates in the female reproductive system. At the centre of interest is the importance of CO for gestation. During the gestation period, CO is an important element affecting the proper function of the feto-placental unit and generally affects fetal survivability rates. Gestation is one of the most important processes of successful reproduction, although there are more relevant processes that need to be researched. While already proven that CO influences steroidogenesis and the corpus luteum survivability rate, our knowledge concerning the function and importance of CO in the reproductive system is still relatively limited. As an example, our knowledge of CO function in an oocyte, the most important cell for reproduction, is almost non-existent. The aim of this review is to summarize our current knowledge concerning the function of CO in the female reproductive system. PMID:28123837

Food availability affects onset of reproduction in a long-lived seabird.

PubMed

Vincenzi, Simone; Hatch, Scott; Mangel, Marc; Kitaysky, Alexander

2013-06-07

Life-history theory predicts that suboptimal developmental conditions may lead to faster life histories (younger age at recruitment and higher reproductive investment), but experimental testing of this prediction is still scarce in long-lived species. We report the effects of an experimental manipulation of food availability during early development and at recruitment on the onset of reproduction and reproductive performance (productivity at first breeding) in a long-lived seabird, the black-legged kittiwake Rissa tridactyla, breeding on Middleton Island, Alaska. Birds were born and raised in nests with supplemented food ('fed') or unsupplemented control nests ('unfed'), and later recruited into either fed or unfed nests. Fed chicks grew faster than unfed chicks, and males grew faster than females. Birds were more likely to reproduce at younger ages when recruiting into fed nests. Faster growth during development tended to increase age at recruitment in all individuals. Social rank of individuals also affected age at recruitment: B-chicks recruited earlier than A-chicks and singletons recruited later than A- and B-chicks. Productivity increased with the age at recruitment and growth rate as chick, but much of the variability remained unexplained. We conclude that results of this study at least partially support predictions of life-history theory: younger age at first breeding for kittiwakes that experienced suboptimal natal conditions, as well as greater productivity of early recruiting kittiwakes that grew in control nests compared with those that grew in food-supplemented nests.

Nest-site selection and reproductive success of greater sage-grouse in a fire-affected habitat of northwestern Nevada

USGS Publications Warehouse

Lockyer, Zachary B.; Coates, Peter S.; Casazza, Michael L.; Espinosa, Shawn; Delehanty, David J.

2015-01-01

Identifying links between micro-habitat selection and wildlife reproduction is imperative to population persistence and recovery. This information is particularly important for landscape species such as greater sage-grouse (Centrocercus urophasianus; sage-grouse). Although this species has been widely studied, because environmental factors can affect sage-grouse populations, local and regional studies are crucial for developing viable conservation strategies. We studied the habitat-use patterns of 71 radio-marked sage-grouse inhabiting an area affected by wildfire in the Virginia Mountains of northwestern Nevada during 2009–2011 to determine the effect of micro-habitat attributes on reproductive success. We measured standard vegetation parameters at nest and random sites using a multi-scale approach (range = 0.01–15,527 ha). We used an information-theoretic modeling approach to identify environmental factors influencing nest-site selection and survival, and determine whether nest survival was a function of resource selection. Sage-grouse selected micro-sites with greater shrub canopy cover and less cheatgrass (Bromus tectorum) cover than random sites. Total shrub canopy, including sagebrush (Artemisia spp.) and other shrub species, at small spatial scales (0.8 ha and 3.1 ha) was the single contributing selection factor to higher nest survival. These results indicate that reducing the risk of wildfire to maintain important sagebrush habitats could be emphasized in sage-grouse conservation strategies in Nevada. Managers may seek to mitigate the influx of annual grass invasion by preserving large intact sagebrush-dominated stands with a mixture of other shrub species. For this area of Nevada, the results suggest that ≥40% total shrub canopy cover in sage-grouse nesting areas could yield improved reproductive success. 

EFFECTS OF SELENIUM ON MALLARD DUCK REPRODUCTION AND IMMUNE FUNCTION

EPA Science Inventory

Selenium from irrigation drain water and coal-fired power stations is a significant environmental contaminant in some regions of the USA. Our objectives were to examine whether selenium-exposed waterfowl had altered immune function, disease resistance, or reproduction. Pairs of a...

Silk amino acids improve physical stamina and male reproductive function of mice.

PubMed

Shin, Sunhee; Yeon, Seongho; Park, Dongsun; Oh, Jiyoung; Kang, Hyomin; Kim, Sunghyun; Joo, Seong Soo; Lim, Woo-Taek; Lee, Jeong-Yong; Choi, Kyung-Chul; Kim, Ki Yon; Kim, Seung Up; Kim, Jong-Choon; Kim, Yun-Bae

2010-01-01

The effects of a silk amino acid (SAA) preparation on the physical stamina and male reproductive function of mice were investigated. Eight-week-old male ICR mice (29-31 g) were orally administered SAA (50, 160 or 500 mg/kg) for 44 d during 30-min daily swimming exercise. The mice were subjected to a weight-loaded (5% of body weight) forced swimming on the 14th, 28th and 42nd day to determine maximum swimming time, and after a 2-d recovery period (treated with SAA without swimming exercise), parameters related to fatigue and reproductive function were analyzed from blood, muscles and reproductive organs. Repeated swimming exercise increased the maximum swimming time to some extent, in spite of a marked reduction in body weight gain, and SAA further enhanced the stamina in a dose-dependent manner. Forced swimming exercises increased blood parameters of tissue injury, but depleted blood glucose and tissue glycogen, which were substantially prevented by SAA treatment. In addition, SAA significantly reduced the muscular thiobarbituric acid-reactive substances and blood corticosterone content increased by forced swimming. Swimming exercise decreased the blood testosterone level, which was recovered by SAA, leading to enhanced sperm counts. These combined results indicate that SAA not only enhances physical stamina by minimizing damage to tissues, including muscles, as well as preventing energy depletion caused by swimming stress, but also improves male reproductive function by increasing testosterone and sperm counts.

HORMONAL CONTROL OF OVARIAN FUNCTION FOLLOWING CHLOROTRIAZINE EXPOSURE: EFFECT ON REPRODUCTIVE FUNCTION AND MAMMARY GLAND TUMOR DEVELOPMENT

EPA Science Inventory

Hormonal Control of Ovarian Function Following Chlorotriazine Exposure: Effect on Reproductive Function and Mammary Gland Tumor Development.

Ralph L. Cooper, Susan C. Laws, Michael G. Narotsky, Jerome M. Goldman, and Tammy E. Stoker

Abstract
The studies review...

A single nucleotide polymorphism in COQ9 affects mitochondrial and ovarian function and fertility in Holstein cows.

PubMed

Ortega, M Sofia; Wohlgemuth, Stephanie; Tribulo, Paula; Siqueira, Luiz G B; Cole, John B; Hansen, Peter J

2017-03-01

A single missense mutation at position 159 of coenzyme Q9 (COQ9) (G→A; rs109301586) has been associated with genetic variation in fertility in Holstein cattle, with the A allele associated with higher fertility. COQ9 is involved in the synthesis of coenzyme COQ10, a component of the electron transport system of the mitochondria. Here we tested whether reproductive phenotype is associated with the mutation and evaluated functional consequences for cellular oxygen metabolism, body weight changes, and ovarian function. The mutation in COQ9 modifies predicted tertiary protein structure and affected mitochondrial respiration of peripheral blood mononuclear cells. The A allele was associated with low resting oxygen consumption and high electron transport system capacity. Phenotypic measurements for fertility were evaluated for up to five lactations in a population of 2273 Holstein cows. There were additive effects of the mutation (P < 0.05) in favor of the A allele for pregnancy rate, interval from calving to conception, and services per conception. There was no association of genotype with milk production or body weight changes postpartum. The mutation in COQ9 affected ovarian function; the A allele was associated with increased mitochondrial DNA copy number in oocytes, and there were overdominance effects for COQ9 expression in oocytes, follicle number, and antimullerian hormone concentrations. Overall, results show how a gene involved in mitochondrial function is associated with overall fertility, possibly in part by affecting oocyte quality. © The Authors 2017. Published by Oxford University Press on behalf of Society for the Study of Reproduction. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Vitamin D is necessary for reproductive functions of the male rat.

PubMed

Kwiecinski, G G; Petrie, G I; DeLuca, H F

1989-05-01

The effect of vitamin D deficiency on the fertility and reproductive capacity of male rats was investigated. Male weanling rats were fed vitamin D-deficient or vitamin D-replete diets until maturity, and mated to age-matched, vitamin D-replete females. Vitamin D-deficient males were capable of reproduction. However, successful matings, i.e., presence of sperm in the vaginal tract of the female, by vitamin D-deficient males were reduced by 45% when compared to matings by vitamin D-replete males. Fertility (successful pregnancies in sperm-positive females) was reduced by 73% in litters from vitamin D-deficient male inseminations when compared to litters from females inseminated by vitamin D-replete males. These results demonstrate that vitamin D and its metabolites are necessary for normal reproductive functions in the male rat.

Changes in Tree Reproductive Traits Reduce Functional Diversity in a Fragmented Atlantic Forest Landscape

PubMed Central

Girão, Luciana Coe; Lopes, Ariadna Valentina; Tabarelli, Marcelo; Bruna, Emilio M.

2007-01-01

Functional diversity has been postulated to be critical for the maintenance of ecosystem functioning, but the way it can be disrupted by human-related disturbances remains poorly investigated. Here we test the hypothesis that habitat fragmentation changes the relative contribution of tree species within categories of reproductive traits (frequency of traits) and reduces the functional diversity of tree assemblages. The study was carried out in an old and severely fragmented landscape of the Brazilian Atlantic forest. We used published information and field observations to obtain the frequency of tree species and individuals within 50 categories of reproductive traits (distributed in four major classes: pollination systems, floral biology, sexual systems, and reproductive systems) in 10 fragments and 10 tracts of forest interior (control plots). As hypothesized, populations in fragments and control plots differed substantially in the representation of the four major classes of reproductive traits (more than 50% of the categories investigated). The most conspicuous differences were the lack of three pollination systems in fragments-pollination by birds, flies and non-flying mammals-and that fragments had a higher frequency of both species and individuals pollinated by generalist vectors. Hermaphroditic species predominate in both habitats, although their relative abundances were higher in fragments. On the contrary, self-incompatible species were underrepresented in fragments. Moreover, fragments showed lower functional diversity (H' scores) for pollination systems (−30.3%), floral types (−23.6%), and floral sizes (−20.8%) in comparison to control plots. In contrast to the overwhelming effect of fragmentation, patch and landscape metrics such as patch size and forest cover played a minor role on the frequency of traits. Our results suggest that habitat fragmentation promotes a marked shift in the relative abundance of tree reproductive traits and greatly

Sex-specific inhibition and stimulation of worker-reproductive transition in a termite.

PubMed

Sun, Qian; Haynes, Kenneth F; Hampton, Jordan D; Zhou, Xuguo

2017-09-06

In social insects, the postembryonic development of individuals exhibits strong phenotypic plasticity in response to the environment, thus generating the caste system. Different from eusocial Hymenoptera, in which queens dominate reproduction and inhibit worker fertility, the primary reproductive caste in termites (kings and queens) can be replaced by neotenic reproductives derived from functionally sterile individuals. Feedback regulation of nestmate differentiation into reproductives has been suggested, but the sex specificity remains inconclusive. In the eastern subterranean termite, Reticulitermes flavipes, we tested the hypothesis that neotenic reproductives regulate worker-reproductive transition in a sex-specific manner. With this R. flavipes system, we demonstrate a sex-specific regulatory mechanism with both inhibitory and stimulatory functions. Neotenics inhibit workers of the same sex from differentiating into additional reproductives but stimulate workers of the opposite sex to undergo this transition. Furthermore, this process is not affected by the presence of soldiers. Our results highlight the reproductive plasticity of termites in response to social cues and provide insights into the regulation of reproductive division of labor in a hemimetabolous social insect.

Sex-specific inhibition and stimulation of worker-reproductive transition in a termite

NASA Astrophysics Data System (ADS)

Sun, Qian; Haynes, Kenneth F.; Hampton, Jordan D.; Zhou, Xuguo

2017-10-01

In social insects, the postembryonic development of individuals exhibits strong phenotypic plasticity in response to the environment, thus generating the caste system. Different from eusocial Hymenoptera, in which queens dominate reproduction and inhibit worker fertility, the primary reproductive caste in termites (kings and queens) can be replaced by neotenic reproductives derived from functionally sterile individuals. Feedback regulation of nestmate differentiation into reproductives has been suggested, but the sex specificity remains inconclusive. In the eastern subterranean termite, Reticulitermes flavipes, we tested the hypothesis that neotenic reproductives regulate worker-reproductive transition in a sex-specific manner. With this R. flavipes system, we demonstrate a sex-specific regulatory mechanism with both inhibitory and stimulatory functions. Neotenics inhibit workers of the same sex from differentiating into additional reproductives but stimulate workers of the opposite sex to undergo this transition. Furthermore, this process is not affected by the presence of soldiers. Our results highlight the reproductive plasticity of termites in response to social cues and provide insights into the regulation of reproductive division of labor in a hemimetabolous social insect.

Social Variables Affecting Mate Preferences, Copulation and Reproductive Outcome in a Pack of Free-Ranging Dogs

PubMed Central

Valsecchi, Paola; Natoli, Eugenia

2014-01-01

Mating and reproductive outcome is often determined by the simultaneous operation of different mechanisms like intra-sexual competition, mating preferences and sexual coercion. The present study investigated how social variables affected mating outcome in a pack of free-ranging dogs, a species supposed to have lost most features of the social system of wolves during domestication. We found that, although the pack comprised multiple breeding individuals, both male copulation success and female reproductive success were positively influenced by a linear combination of dominance rank, age and leadership. Our results also suggest that mate preferences affect mating outcome by reinforcing the success of most dominant individuals. In particular, during their oestrous period bitches clearly searched for the proximity of high-ranking males who displayed affiliative behaviour towards them, while they were more likely to reject the males who intimidated them. At the same time, male courting effort and male-male competition for receptive females appeared to be stronger in the presence of higher-ranking females, suggesting a male preference for dominant females. To our knowledge, these results provide the first clear evidence of social regulation of reproductive activities in domestic dogs, and suggest that some common organizing mechanisms may contribute to shape the social organization of both dogs and wolves. PMID:24905360

Impact of Marine Drugs on Animal Reproductive Processes

PubMed Central

Silvestre, Francesco; Tosti, Elisabetta

2009-01-01

The discovery and description of bioactive substances from natural sources has been a research topic for the last 50 years. In this respect, marine animals have been used to extract many new compounds exerting different actions. Reproduction is a complex process whose main steps are the production and maturation of gametes, their activation, the fertilisation and the beginning of development. In the literature it has been shown that many substances extracted from marine organisms may have profound influence on the reproductive behaviour, function and reproductive strategies and survival of species. However, despite the central importance of reproduction and thus the maintenance of species, there are still few studies on how reproductive mechanisms are impacted by marine bioactive drugs. At present, studies in either marine and terrestrial animals have been particularly important in identifying what specific fine reproductive mechanisms are affected by marine-derived substances. In this review we describe the main steps of the biology of reproduction and the impact of substances from marine environment and organisms on the reproductive processes. PMID:20098597

Microcystin-LR impairs zebrafish reproduction by affecting oogenesis and endocrine system.

PubMed

Zhao, Yanyan; Xie, Liqiang; Yan, Yunjun

2015-02-01

Previous studies have shown that microcystins (MCs) are able to exert negative effects on the reproductive system of fish. However, few data are actually available on the effects of MC-LR on the reproductive system of female fish. In the present study, female zebrafish were exposed to 2, 10, and 50 μg L(-1) of MC-LR for 21 d, and its effects on oogenesis, sex hormones, transcription of genes on the hypothalamic-pituitary-gonad (HPG) axis, and reproduction were investigated for the first time. It was observed that egg production significantly declined at ⩾ 10 μg L(-1) MC-LR. MC-LR exposure to zebrafish increased the concentrations of 17β-estradiol (E2) and vitellogenin (VTG) at 10 μg L(-1) level, whereas concentrations of E2, VTG and testosterone declined at 50 μg L(-1) MC-LR. The transcriptions of steroidogenic pathway gene (cyp19a, cyp19b, 17βhsd, cyp17 and hmgra) changed as well after the exposure and corresponded well with the alterations of hormone levels. A number of intra- and extra-ovarian factors, such as gnrh3, gnrhr1, fshβ, fshr, lhr, bmp15, mrpβ, ptgs2 and vtg1 which regulate oogenesis, were significantly changed with a different dose-related effect. Moreover, MC-LR exposure to female zebrafish resulted in decreased fertilization and hatching rates, and may suggest the possibility of trans-generational effects of MC-LR exposure. The results demonstrate that MC-LR could modulate endocrine function and oogenesis, eventually leading to disruption of reproductive performance in female zebrafish. These data suggest there is a risk for aquatic population living in MC polluted areas. Copyright © 2014 Elsevier Ltd. All rights reserved.

Energy-containing beverages: reproductive hormones and ovarian function in the BioCycle Study123

PubMed Central

Schliep, Karen C; Mumford, Sunni L; Pollack, Anna Z; Perkins, Neil J; Ye, Aijun; Zhang, Cuilin J; Stanford, Joseph B; Porucznik, Christina A; Hammoud, Ahmad O; Wactawski-Wende, Jean

2013-01-01

Background: Energy-containing beverages are widely consumed among premenopausal women, but their association with reproductive hormones is not well understood. Objective: The objective was to assess the association of energy-containing beverages, added sugars, and total fructose intake with reproductive hormones among ovulatory cycles and sporadic anovulation in healthy premenopausal women. Design: Women (n = 259) in the BioCycle Study were followed for up to 2 menstrual cycles; they provided fasting blood specimens during up to 8 visits/cycle and four 24-h dietary recalls/cycle. Results: Women who consumed ≥1 cup (1 cup = 237 mL) sweetened soda/d had 16.3% higher estradiol concentrations compared with women who consumed less sweetened soda (86.5 pg/mL compared with 74.4 pg/mL, P = 0.01) after adjustment for age, BMI, race, dietary factors, and physical activity. Similarly elevated estradiol concentrations were found for ≥1 cup cola/d and noncola soda intake. Neither artificially sweetened soda nor fruit juice intake ≥1 cup/d was significantly associated with reproductive hormones. Added sugar above the average US woman's intake (≥73.2 g/d) or above the 66th percentile in total fructose intake (≥41.5 g/d) was associated with significantly elevated estradiol but not consistently across all models. No associations were found between beverages, added sugars, or total fructose intake and anovulation after multivariate adjustment. Conclusions: Even at moderate consumption amounts, sweetened soda is associated with elevated follicular estradiol concentrations among premenopausal women but does not appear to affect ovulatory function. Further research into the mechanism driving the association between energy-containing beverages and reproductive hormones, and its potential implications for women's health, is warranted. PMID:23364018

Sexual Function Across Aging.

PubMed

Clayton, Anita H; Harsh, Veronica

2016-03-01

Women experience multiple changes in social and reproductive statuses across the life span which can affect sexual functioning. Various phases of the sexual response cycle may be impacted and can lead to sexual dysfunction. Screening for sexual problems and consideration of contributing factors such as neurobiology, reproductive life events, medical problems, medication use, and depression can help guide appropriate treatment and thereby improve the sexual functioning and quality of life of affected women. Treatment options include psychotropic medications, hormone therapy, and psychotherapy.

All Eggs Are Not Equal: The Maternal Environment Affects Progeny Reproduction and Developmental Fate in Caenorhabditis elegans

PubMed Central

Harvey, Simon C.; Orbidans, Helen E.

2011-01-01

Background Maternal effects on progeny traits are common and these can profoundly alter progeny life history. Maternal effects can be adaptive, representing attempts to appropriately match offspring phenotype to the expected environment and are often mediated via trade-offs between progeny number and quality. Here we have investigated the effect of maternal food availability on progeny life history in the free-living nematode Caenorhabditis elegans. Methodology/Principal Findings The maternal environment affects both reproductive traits and progeny development. Comparisons of the progeny of worms from high and low maternal food environments indicates that low maternal food availability reduces progeny reproduction in good environments, increases progeny reproduction in poor environments and decreases the likelihood that progeny will develop as dauer larvae. These analyses also indicate that the effects on progeny are not a simple consequence of changes in maternal body size, but are associated with an increase in the size of eggs produced by worms at low maternal food availabilities. Conclusions/Significance These results indicate that the maternal environment affects both progeny reproduction and development in C. elegans and therefore that all progeny are not equal. The observed effects are consistent with changes to egg provisioning, which are beneficial in harsh environments, and of changes to progeny development, which are beneficial in harsh environments and detrimental in benign environments. These changes in progeny life history suggest that mothers in poor quality environments may be producing larger eggs that are better suited to poor conditions. PMID:21991370

Neuroendocrine control of reproductive aging: roles of GnRH neurons.

PubMed

Yin, Weiling; Gore, Andrea C

2006-03-01

The process of reproductive senescence in many female mammals, including humans, is characterized by a gradual transition from regular reproductive cycles to irregular cycles to eventual acyclicity, and ultimately a loss of fertility. In the present review, the role of the hypothalamic gonadotropin-releasing hormone (GnRH) neurons is considered in this context. GnRH neurons provide the primary driving force upon the other levels of the reproductive axis. With respect to aging, GnRH cells undergo changes in biosynthesis, processing and release of the GnRH decapeptide. GnRH neurons also exhibit morphologic and ultrastructural alterations that appear to underlie these biosynthetic properties. Thus, functional and morphologic changes in the GnRH neurosecretory system may play causal roles in the transition to acyclicity. In addition, GnRH neurons are regulated by numerous inputs from neurotransmitters, neuromodulators and glia. The relationship among GnRH cells and their inputs at the cell body (thereby affecting GnRH biosynthesis) and the neuroterminal (thereby affecting GnRH neurosecretion) is crucial to the function of the GnRH system, with age-related changes in these relationships contributing to the reproductive senescent process. Therefore, the aging hypothalamus is characterized by changes intrinsic to the GnRH cell, as well as its regulatory inputs, which summate to contribute to a loss of reproductive competence in aging females.

Melatonin and female reproduction.

PubMed

Tamura, Hiroshi; Takasaki, Akihisa; Taketani, Toshiaki; Tanabe, Manabu; Lee, Lifa; Tamura, Isao; Maekawa, Ryo; Aasada, Hiromi; Yamagata, Yoshiaki; Sugino, Norihiro

2014-01-01

Melatonin (N-acetyl-5-methoxytryptamine) is secreted during the dark hours at night by the pineal gland. After entering the circulation, melatonin acts as an endocrine factor and a chemical messenger of light and darkness. It regulates a variety of important central and peripheral actions related to circadian rhythms and reproduction. It also affects the brain, immune, gastrointestinal, cardiovascular, renal, bone and endocrine functions and acts as an oncostatic and anti-aging molecule. Many of melatonin's actions are mediated through interactions with specific membrane-bound receptors expressed not only in the central nervous system, but also in peripheral tissues. Melatonin also acts through non-receptor-mediated mechanisms, for example serving as a scavenger for reactive oxygen species and reactive nitrogen species. At both physiological and pharmacological concentrations, melatonin attenuates and counteracts oxidative stress and regulates cellular metabolism. Growing scientific evidence of reproductive physiology supports the role of melatonin in human reproduction. This review was conducted to investigate the effects of melatonin on female reproduction and to summarize our findings in this field. © 2013 The Authors. Journal of Obstetrics and Gynaecology Research © 2013 Japan Society of Obstetrics and Gynecology.

Can aircraft noise less than or equal 115 to dBA adversely affect reproductive outcome in USAF women?

NASA Astrophysics Data System (ADS)

Brubaker, P. A.

1985-06-01

It has been suggested, mainly through animal studies, that exposure to high noise levels may be associated with lower birth weight, reduced gestational length and other adverse reproductive outcomes. Few studies have been done on humans to show this association. The Air Force employs pregnant women in areas where there is a high potential for exposure to high noise levels. This study proposes a method to determine if there is an association between high frequency noise levels or = 115 dBA and adverse reproductive outcomes through a review of records and self-administered questionnaires in a case-comparison design. Prevelance rates will be calculated and a multiple logistic regression analysis computed for the independent variables that can affect reproduction.

Toxicological assessment of Diplazium esculentum on the reproductive functions of male Swiss albino mouse.

PubMed

Roy, Subhrajyoti; Chaudhuri, Tapas Kumar

2017-04-01

Diplazium esculentum, a commonly consumed seasonal vegetable, has been reported to have some pathological effects in some animals. But, its effect on the male reproductive function has not yet been studied. To investigate the effects of boiled D. esculentum (BDE), the form which human consumes, on male reproductive functions of Swiss albino mice. Male (120 in no.) and female (80 in no.) Swiss albino mice (6-8 weeks of age) were fed orally with 80, 160 and 320 mg/kg bw of BDE within a span of 180 d. After the treatment, body weight, absolute- and relative-testis weight, relative-weight of other organs, their biochemical parameters, hypo-osmotic swelling test (HOST) of spermatozoa, testis histology and fertility and fecundity tests were performed to justify the toxic effects of D. esculentum on male reproductive functions. Significant dose- and time-dependent decreases were observed in body weight, absolute- and relative-testis weight, relative-weights of other organs and their biochemical parameters, percentage of live spermatozoa and percentage of fertility and fecundity in BDE fed mice. Significant decreases were observed in diameter, perimeter and area of the seminiferous tubules of mice treated for 180 d. The percentage of empty seminiferous tubules was increased significantly in BDE treated mice when compared to the controls. These results suggest that the intake of D. esculentum, even after cooking, may induce infertility by altering the male reproductive function, and therefore, should be evaluated further as a potential antifertility agent.

Ovarian function and reproductive outcomes of female patients with systemic lupus erythematosus and the strategies to preserve their fertility.

PubMed

Oktem, Ozgur; Guzel, Yılmaz; Aksoy, Senai; Aydin, Elvin; Urman, Bulent

2015-03-01

Systemic lupus erythematosus (SLE) is a chronic autoimmune systemic disease that mainly affects women of reproductive age. Emerging data from recent molecular studies show us that estrogen hormone plays a central role in the development of this disease. By acting via its cognate receptors ERα and ERβ expressed on immune cells, estrogen can modulate immune function in both the innate and adaptive immune responses. Interestingly, estrogen may also evoke autoimmune responses after binding to B lymphocytes leading to the generation of high-affinity autoantibodies and proinflammatory cytokines (so-called estrogen-induced autoimmunity). Unfortunately, reproductive function of young female patients with this disease is commonly compromised by different pathophysiologic processes. First, ovarian reserve is diminished even in the presence of mild disease suggesting a direct impact of the disease itself on ovarian function possibly due to ovarian involvement in the form of autoimmune oophoritis. Second, SLE patients with severe manifestations of the disease are treated with alkylating chemotherapy agent cyclophosphamide. Cyclophosphamide and other drugs of alkylating category have the highest gonadotoxicity. Therefore, SLE patients exposed to cyclophosphamide have a much higher risk of developing infertility and premature ovarian failure than do the counterparts who are treated with other less toxic treatments. Third, the functions of the hypothalamic pituitary ovarian axis are perturbed by chronic inflammatory state. And finally adverse pregnancy outcomes are more commonly observed in SLE patients such as fetal loss, preterm birth, intrauterine fetal growth restriction, preeclampsia-eclampsia, and fetal congenital heart block. We aimed in this review article to provide the readers an update on how estrogen hormone closely interacts with and induces lupus-prone changes in the immune system. We also discuss ovarian function and other reproductive outcomes in SLE patients

Urinary phthalate metabolites and male reproductive function parameters in Chongqing general population, China.

PubMed

Han, Xue; Cui, Zhihong; Zhou, Niya; Ma, Mingfu; Li, Lianbing; Li, Yafei; Lin, Hui; Ao, Lin; Shu, Weiqun; Liu, Jinyi; Cao, Jia

2014-03-01

This study was designed to investigate the phthalates exposure levels in general population in Chongqing City of China, and to determine the possible associations between phthalate exposure and male reproductive function parameters. We recruited 232 general men through Chongqing Family Planning Research Institute and Reproductive Center of Chongqing. In a single spot urine sample from each man, phthalate metabolites, including mono-butyl phthalate (MBP), mono-ethyl phthalate (MEP), mono-(2-ethylhexyl) phthalate (MEHP), mono-benzyl phthalate (MBzP), phthalic acid (PA), and total PA were analyzed using solid phase extraction and coupled with high-performance liquid chromatography and detection by tandem mass spectrometry. Semen parameters were dichotomized based on World Health Organization reference values. Sperm DNA damage were analyzed using the alkaline single-cell gel electrophoresis assay. Reproductive hormones were determined in serum by the radioimmunoassay kit. We observed a weak association between urinary MBP concentration and sperm concentration in Chongqing general population. MBP levels above the median were 1.97 times (95% confidence interval [CI] 0.97-4.04) more likely to have sperm concentration below the reference value. There were no other associations between phthalate metabolites and reproductive function parameters after adjusted for potential risk factors. Our study suggested that general population in Chongqing area of China exposure to the environmental level of phthalate have weak or without adverse effects on the reproduction. Copyright © 2013 Elsevier GmbH. All rights reserved.

Genetic differentiation for size at first reproduction through male versus female functions in the widespread Mediterranean tree Pinus pinaster.

PubMed

Santos-del-Blanco, L; Climent, J; González-Martínez, S C; Pannell, J R

2012-11-01

The study of local adaptation in plant reproductive traits has received substantial attention in short-lived species, but studies conducted on forest trees are scarce. This lack of research on long-lived species represents an important gap in our knowledge, because inferences about selection on the reproduction and life history of short-lived species cannot necessarily be extrapolated to trees. This study considers whether the size for first reproduction is locally adapted across a broad geographical range of the Mediterranean conifer species Pinus pinaster. In particular, the study investigates whether this monoecious species varies genetically among populations in terms of whether individuals start to reproduce through their male function, their female function or both sexual functions simultaneously. Whether differences among populations could be attributed to local adaptation across a climatic gradient is then considered. Male and female reproduction and growth were measured during early stages of sexual maturity of a P. pinaster common garden comprising 23 populations sampled across the species range. Generalized linear mixed models were used to assess genetic variability of early reproductive life-history traits. Environmental correlations with reproductive life-history traits were tested after controlling for neutral genetic structure provided by 12 nuclear simple sequence repeat markers. Trees tended to reproduce first through their male function, at a size (height) that varied little among source populations. The transition to female reproduction was slower, showed higher levels of variability and was negatively correlated with vegetative growth traits. Several female reproductive traits were correlated with a gradient of growth conditions, even after accounting for neutral genetic structure, with populations from more unfavourable sites tending to commence female reproduction at a lower individual size. The study represents the first report of genetic

Hormonal, biochemical, and hematological profiles in female camels (Camelus dromedarius) affected with reproductive disorders.

PubMed

Ali, A; Tharwat, M; Al-Sobayil, F A

2010-04-01

The aim of this study was to assess the blood profiles in female camels affected with common reproductive disorders. Estradiol-17beta (E(2)), progesterone (P(4)), thyroxin (T(4)), zinc (Zn), copper (Cu), calcium (Ca), phosphorus (P), magnesium (Mg), cholesterol, glucose, triglycerides, total protein, albumin, globulin, hematocrite, and total and differential white blood cell counts (WBC) were determined in blood of female camels affected with endometritis (n=15), vaginal adhesions (n=15), and ovarian cysts (n=15). Normal cyclic animals were used as controls (n=15). Diagnosis of reproductive disorders was based on transrectal palpation, ultrasonographic examination, and exploration of the vagina. Increased WBC counts (P=0.03) and a tendency for neutrophelia (P=0.05) were noted in female camels with vaginal adhesions. These animals were also characterized by having higher concentration of serum P(4) (P=0.0001), T(4) (P=0.001) and total protein (P=0.007), in comparison with female camels with endometritis, ovarian cysts, or controls. Animals having ovarian cysts with thin walls and homogenous hypoechogenic contents had greater serum E(2) (P=0.001) and P(4) (P=0.0001) than those having ovarian cysts with thick walls and non-homogenous echogenic contents. Animals with endometritis, vaginal adhesions, and ovarian cysts revealed lower serum Zn concentration than that of control group (P=0.003). Other blood parameters did not differ significantly compared to controls. In conclusion, this is the first report characterizing blood constituents in female camels with various reproductive disorders. These profiles may be valuable in clarifying the etio-pathogenesis of these disorders. Copyright 2009 Elsevier B.V. All rights reserved.

Bone Morphogenetic Protein (BMP) signaling in animal reproductive system development and function.

PubMed

Lochab, Amaneet K; Extavour, Cassandra G

2017-07-15

In multicellular organisms, the specification, maintenance, and transmission of the germ cell lineage to subsequent generations are critical processes that ensure species survival. A number of studies suggest that the Bone Morphogenetic Protein (BMP) pathway plays multiple roles in this cell lineage. We wished to use a comparative framework to examine the role of BMP signaling in regulating these processes, to determine if patterns would emerge that might shed light on the evolution of molecular mechanisms that may play germ cell-specific or other reproductive roles across species. To this end, here we review evidence to date from the literature supporting a role for BMP signaling in reproductive processes across Metazoa. We focus on germ line-specific processes, and separately consider somatic reproductive processes. We find that from primordial germ cell (PGC) induction to maintenance of PGC identity and gametogenesis, BMP signaling regulates these processes throughout embryonic development and adult life in multiple deuterostome and protostome clades. In well-studied model organisms, functional genetic evidence suggests that BMP signaling is required in the germ line across all life stages, with the exception of PGC specification in species that do not use inductive signaling to induce germ cell formation. The current evidence is consistent with the hypothesis that BMP signaling is ancestral in bilaterian inductive PGC specification. While BMP4 appears to be the most broadly employed ligand for the reproductive processes considered herein, we also noted evidence for sex-specific usage of different BMP ligands. In gametogenesis, BMP6 and BMP15 seem to have roles restricted to oogenesis, while BMP8 is restricted to spermatogenesis. We hypothesize that a BMP-based mechanism may have been recruited early in metazoan evolution to specify the germ line, and was subsequently co-opted for use in other germ line-specific and somatic reproductive processes. We suggest

Effects of selenium on mallard duck reproduction and immune function

DOE Office of Scientific and Technical Information (OSTI.GOV)

Whiteley, P.L.; Yuill, T.M.; Fairbrother, A.

Selenium from irrigation drain water and coal-fired power stations is a significant environmental contaminant in some regions of the USA. The objectives were to examine whether selenium-exposed waterfowl had altered immune function, disease resistance, or reproduction. Pairs of adult mallards were exposed for 95-99 days on streams with sodium selenite-treated water at 10 and 30 ppb, or on untreated streams. Selenium biomagnified through the food chain to the ducks. Disease resistance was decreased in ducklings hatched on the streams and challenged with duck hepatitis virus 1 (DHV1) when 15-days old. Liver selenium concentrations for these ducklings on the 10 andmore » 30 ppb streams was 3.6 and 7.6 ppm dry weight, respectively. Mortality of ducklings purchased when 7-days old, exposed to selenium for 14 days, and challenged when 22-days old was not affected. However, their selenium exposure was lower (liver selenium 4.1 ppm dry weight for the 30 ppb stream). Five parameters of immune function were measured in adult ducks. Phagocytosis of killed Pasteurella multocida by blood heterophils and monocytes, and blood monocyte concentrations were higher in adult males following 84 days exposure to 30 ppb selenium. Their liver selenium concentrations were 11.1 ppm dry weight after 95-99 days exposure.« less

Does time after pair bond disruption affect subsequent reproduction in the socially monogamous woodland vole (Microtus pinetorum)?

PubMed Central

Renfro, Caroline A.; Pesek, Daniel W.; Bobeck, Kelly; Solomon, Nancy G.

2010-01-01

Disruption of the pair bond between socially monogamous animals leads to changes in behavior, which may have reproductive consequences. There are two alternative hypotheses to explain the effect of the length of time since pair bond disruption on subsequent reproduction. One hypothesis predicts that voles housed immediately with a new opposite-sex conspecific will be as likely to produce litters and will produce them as quickly as voles separated from their initial mate for longer. Alternatively, if attachment between mates is enduring, we expect that more voles separated longer from their previous mates will produce litters and produce them sooner than voles re-paired immediately after separation from their initial mates. Woodland voles, paired with opposite-sex conspecifics, remained together until parturition. Mates were then separated for zero, seven, or fourteen days until re-pairing with an opposite-sex conspecific. Pair bond disruption did not prevent males and females from mating subsequently, which was consistent with data from our breeding colony. In addition, the length of time an individual remained alone after pair bond disruption did not affect the latency to produce a litter. Our results show that having been paired previously does not affect subsequent reproduction in this socially monogamous vole. PMID:19429197

EFFECTS OF METAM SODIUM ON REPRODUCTIVE FUNCTION IN THE FEMALE RAT

EPA Science Inventory

Metam sodium (MS) is a soil fumigant and Category III pesticide with a relatively low toxicity in mammals. But, there is some indication that it can impair rodent reproductive function. In ovariectomized, estradiol-primed rats, a single ip injection was reported to block the lute...

Influence of Reproductive Aging of the Cow on Luteal Function and Period 1 mRNA Expression

USDA-ARS?s Scientific Manuscript database

In rodents, disruption of the circadian clock genes results in increased incidence of anovulation, irregular estrous cycles, decreased luteal function, and accelerated reproductive ageing. In cattle, reproductive ageing is associated with decreased numbers of follicles in the ovary, decreased lutea...

Wolbachia Affects Reproduction and Population Dynamics of the Coffee Berry Borer (Hypothenemus hampei): Implications for Biological Control

PubMed Central

Mariño, Yobana A.; Verle Rodrigues, José C.; Bayman, Paul

2017-01-01

Wolbachia are widely distributed endosymbiotic bacteria that influence the reproduction and fitness of their hosts. In recent years the manipulation of Wolbachia infection has been considered as a potential tool for biological control. The coffee berry borer (CBB), Hypothenemus hampei, is the most devastating coffee pest worldwide. Wolbachia infection in the CBB has been reported, but until now the role of Wolbachia in CBB reproduction and fitness has not been tested. To address this issue we reared the CBB in artificial diets with and without tetracycline (0.1% w/v) for ten generations. Tetracycline reduced significantly the relative proportion of Wolbachia in the CBB microbiota from 0.49% to 0.04%. This reduction affected CBB reproduction: females fed with tetracycline had significantly fewer progeny, lower fecundity, and fewer eggs per female. Tetracycline also reduced the population growth rate (λ), net reproductive rate (R0), and mean generation time (T) in CBB; the reduction in population growth was mostly due to variation in fertility, according to life time response experiments (LTREs) analysis. Our results suggest that Wolbachia contribute to the reproductive success of the CBB and their manipulation represents a possible approach to CBB biocontrol mediated by microbiome management. PMID:28085049

Reproductive Steroid Regulation of Mood and Behavior.

PubMed

Schiller, Crystal Edler; Johnson, Sarah L; Abate, Anna C; Schmidt, Peter J; Rubinow, David R

2016-06-13

In this article, we examine evidence supporting the role of reproductive steroids in the regulation of mood and behavior in women and the nature of that role. In the first half of the article, we review evidence for the following: (i) the reproductive system is designed to regulate behavior; (ii) from the subcellular to cellular to circuit to behavior, reproductive steroids are powerful neuroregulators; (iii) affective disorders are disorders of behavioral state; and (iv) reproductive steroids affect virtually every system implicated in the pathophysiology of depression. In the second half of the article, we discuss the diagnosis of the three reproductive endocrine-related mood disorders (premenstrual dysphoric disorder, postpartum depression, and perimenopausal depression) and present evidence supporting the relevance of reproductive steroids to these conditions. Existing evidence suggests that changes in reproductive steroid levels during specific reproductive states (i.e., the premenstrual phase of the menstrual cycle, pregnancy, parturition, and the menopause transition) trigger affective dysregulation in susceptible women, thus suggesting the etiopathogenic relevance of these hormonal changes in reproductive mood disorders. Understanding the source of individual susceptibility is critical to both preventing the onset of illness and developing novel, individualized treatments for reproductive-related affective dysregulation. © 2016 American Physiological Society. Compr Physiol 6:1135-1160, 2016e. Copyright © 2016 John Wiley & Sons, Inc.

Bisphenol A affects androgen receptor function via multiple mechanisms.

PubMed

Teng, Christina; Goodwin, Bonnie; Shockley, Keith; Xia, Menghang; Huang, Ruili; Norris, John; Merrick, B Alex; Jetten, Anton M; Austin, Christopher P; Tice, Raymond R

2013-05-25

Bisphenol A (BPA), is a well-known endocrine disruptor compound (EDC) that affects the normal development and function of the female and male reproductive system, however the mechanisms of action remain unclear. To investigate the molecular mechanisms of how BPA may affect ten different nuclear receptors, stable cell lines containing individual nuclear receptor ligand binding domain (LBD)-linked to the β-Gal reporter were examined by a quantitative high throughput screening (qHTS) format in the Tox21 Screening Program of the NIH. The results showed that two receptors, estrogen receptor alpha (ERα) and androgen receptor (AR), are affected by BPA in opposite direction. To confirm the observed effects of BPA on ERα and AR, we performed transient transfection experiments with full-length receptors and their corresponding response elements linked to luciferase reporters. We also included in this study two BPA analogs, bisphenol AF (BPAF) and bisphenol S (BPS). As seen in African green monkey kidney CV1 cells, the present study confirmed that BPA and BPAF act as ERα agonists (half maximal effective concentration EC50 of 10-100 nM) and as AR antagonists (half maximal inhibitory concentration IC50 of 1-2 μM). Both BPA and BPAF antagonized AR function via competitive inhibition of the action of synthetic androgen R1881. BPS with lower estrogenic activity (EC50 of 2.2 μM), did not compete with R1881 for AR binding, when tested at 30 μM. Finally, the effects of BPA were also evaluated in a nuclear translocation assays using EGPF-tagged receptors. Similar to 17β-estradiol (E2) which was used as control, BPA was able to enhance ERα nuclear foci formation but at a 100-fold higher concentration. Although BPA was able to bind AR, the nuclear translocation was reduced. Furthermore, BPA was unable to induce functional foci in the nuclei and is consistent with the transient transfection study that BPA is unable to activate AR. Published by Elsevier Ireland Ltd.

[The function of ERα in male reproductive system].

PubMed

Dong, Yu-Hang; Wei, Jin-Hua; Li, Zhen

2014-12-01

Estrogen receptors (ERs), including two sub-types ERα and ERβ, belong to the steroid hormone superfamily of nuclear receptors. ERα distributes in the male reproductive system and plays a crucial role in the regulation of male reproduction through estrogen-dependent and -independent ways. In this article, we mainly reviewed the molecular structure, mode of action and location of ERα in the male reproductive system, and explored the mechanism of ERα in regulating the male reproductive system by analyzing different animal models of disrupted ERα.

Genetic differentiation for size at first reproduction through male versus female functions in the widespread Mediterranean tree Pinus pinaster

PubMed Central

Santos-del-Blanco, L.; Climent, J.; González-Martínez, S. C.; Pannell, J. R.

2012-01-01

Background and Aims The study of local adaptation in plant reproductive traits has received substantial attention in short-lived species, but studies conducted on forest trees are scarce. This lack of research on long-lived species represents an important gap in our knowledge, because inferences about selection on the reproduction and life history of short-lived species cannot necessarily be extrapolated to trees. This study considers whether the size for first reproduction is locally adapted across a broad geographical range of the Mediterranean conifer species Pinus pinaster. In particular, the study investigates whether this monoecious species varies genetically among populations in terms of whether individuals start to reproduce through their male function, their female function or both sexual functions simultaneously. Whether differences among populations could be attributed to local adaptation across a climatic gradient is then considered. Methods Male and female reproduction and growth were measured during early stages of sexual maturity of a P. pinaster common garden comprising 23 populations sampled across the species range. Generalized linear mixed models were used to assess genetic variability of early reproductive life-history traits. Environmental correlations with reproductive life-history traits were tested after controlling for neutral genetic structure provided by 12 nuclear simple sequence repeat markers. Key Results Trees tended to reproduce first through their male function, at a size (height) that varied little among source populations. The transition to female reproduction was slower, showed higher levels of variability and was negatively correlated with vegetative growth traits. Several female reproductive traits were correlated with a gradient of growth conditions, even after accounting for neutral genetic structure, with populations from more unfavourable sites tending to commence female reproduction at a lower individual size. Conclusions

The Rice Receptor-Like Kinases DWARF AND RUNTISH SPIKELET1 and 2 Repress Cell Death and Affect Sugar Utilization during Reproductive Development

PubMed Central

Song, Feng-Yan; Zhao, Ying; Wang, Chun-Yan; Zhang, Yong-Cun; Yang, Qian; Wang, Jiao; Bu, Shuo-Lei; Sun, Li-Jing; Zhang, Sheng-Wei; Zhang, Su-Qiao; Sun, Da-Ye

2017-01-01

Cell-to-cell communication precisely controls the creation of new organs during reproductive growth. However, the sensor molecules that mediate developmental signals in monocot plants are poorly understood. Here, we report that DWARF AND RUNTISH SPIKELET1 (DRUS1) and DRUS2, two closely related receptor-like kinases (RLKs), redundantly control reproductive growth and development in rice (Oryza sativa). A drus1-1 drus2 double knockout mutant, but not either single mutant, showed extreme dwarfism and barren inflorescences that harbored sterile spikelets. The gibberellin pathway was not impaired in this mutant. A phenotypic comparison of mutants expressing different amounts of DRUS1 and 2 revealed that reproductive growth requires a threshold level of DRUS1/2 proteins. DRUS1 and 2 maintain cell viability by repressing protease-mediated cell degradation and likely by affecting sugar utilization or conversion. In the later stages of anther development, survival of the endothecium requires DRUS1/2, which may stimulate expression of the UDP-glucose pyrophosphorylase gene UGP2 and starch biosynthesis in pollen. Unlike their Arabidopsis thaliana ortholog FERONIA, DRUS1 and 2 mediate a fundamental signaling process that is essential for cell survival and represents a novel biological function for the CrRLK1L RLK subfamily. PMID:28082384

Reproductive science as an essential component of conservation biology.

PubMed

Holt, William V; Brown, Janine L; Comizzoli, Pierre

2014-01-01

In this chapter we argue that reproductive science in its broadest sense has never been more important in terms of its value to conservation biology, which itself is a synthetic and multidisciplinary topic. Over recent years the place of reproductive science in wildlife conservation has developed massively across a wide and integrated range of cutting edge topics. We now have unprecedented insight into the way that environmental change affects basic reproductive functions such as ovulation, sperm production, pregnancy and embryo development through previously unsuspected influences such as epigenetic modulation of the genome. Environmental change in its broadest sense alters the quality of foodstuffs that all animals need for reproductive success, changes the synchrony between breeding seasons and reproductive events, perturbs gonadal and embryo development through the presence of pollutants in the environment and drives species to adapt their behaviour and phenotype. In this book we explore many aspects of reproductive science and present wide ranging and up to date accounts of the scientific and technological advances that are currently enabling reproductive science to support conservation biology.

The SLIT/ROBO pathway: a regulator of cell function with implications for the reproductive system

PubMed Central

Dickinson, Rachel E; Duncan, W Colin

2010-01-01

The secreted SLIT glycoproteins and their Roundabout (ROBO) receptors were originally identified as important axon guidance molecules. They function as a repulsive cue with an evolutionarily conserved role in preventing axons from migrating to inappropriate locations during the assembly of the nervous system. In addition the SLIT-ROBO interaction is involved in the regulation of cell migration, cell death and angiogenesis and, as such, has a pivotal role during the development of other tissues such as the lung, kidney, liver and breast. The cellular functions that the SLIT/ROBO pathway controls during tissue morphogenesis are processes that are dysregulated during cancer development. Therefore inactivation of certain SLITs and ROBOs is associated with advanced tumour formation and progression in disparate tissues. Recent research has indicated that the SLIT/ROBO pathway could also have important functions in the reproductive system. The fetal ovary expresses most members of the SLIT and ROBO families. The SLITs and ROBOs also appear to be regulated by steroid hormones and regulate physiological cell functions in adult reproductive tissues such as the ovary and endometrium. Furthermore several SLITs and ROBOs are aberrantly expressed during the development of ovarian, endometrial, cervical and prostate cancer. This review will examine the roles this pathway could have in the development, physiology and pathology of the reproductive system and highlight areas for future research that could further dissect the influence of the SLIT/ROBO pathway in reproduction. PMID:20100881

The SLIT-ROBO pathway: a regulator of cell function with implications for the reproductive system.

PubMed

Dickinson, Rachel E; Duncan, W Colin

2010-04-01

The secreted SLIT glycoproteins and their Roundabout (ROBO) receptors were originally identified as important axon guidance molecules. They function as a repulsive cue with an evolutionarily conserved role in preventing axons from migrating to inappropriate locations during the assembly of the nervous system. In addition the SLIT-ROBO interaction is involved in the regulation of cell migration, cell death and angiogenesis and, as such, has a pivotal role during the development of other tissues such as the lung, kidney, liver and breast. The cellular functions that the SLIT/ROBO pathway controls during tissue morphogenesis are processes that are dysregulated during cancer development. Therefore inactivation of certain SLITs and ROBOs is associated with advanced tumour formation and progression in disparate tissues. Recent research has indicated that the SLIT/ROBO pathway could also have important functions in the reproductive system. The fetal ovary expresses most members of the SLIT and ROBO families. The SLITs and ROBOs also appear to be regulated by steroid hormones and regulate physiological cell functions in adult reproductive tissues such as the ovary and endometrium. Furthermore several SLITs and ROBOs are aberrantly expressed during the development of ovarian, endometrial, cervical and prostate cancer. This review will examine the roles this pathway could have in the development, physiology and pathology of the reproductive system and highlight areas for future research that could further dissect the influence of the SLIT/ROBO pathway in reproduction.

Effect of feeding a high-fat diet independently of caloric intake on reproductive function in diet-induced obese female rats

PubMed Central

Hussain, Mona A.; Abogresha, Noha M.; Tamany, Dalia A.; Lotfy, Mariam

2016-01-01

Introduction Globally, the prevalence of overweight and obesity is increasing, predisposing females to health hazards including compromised reproductive capacity. Our objective was to investigate the effect of ad libitum, isocalorically and hypocalorically restricted high-fat diet (HFD) feeding on reproductive function in diet-induced obese female rats. Material and methods Twenty female albino Sprague Dawley rats were used; 5 rats were kept on a standard pellet animal diet to serve as a control group (A) and 15 rats were fed a HFD for 9 weeks to induce obesity. The HFD fed animals were equally divided into three groups: an ad libitum HFD group (B), an isocalorically restricted HFD group (C), and a hypocalorically restricted HFD group (D). Estrous cyclicity, hormonal levels, ovarian histopathology and caspase-3 immunoreactivity were evaluated. Results The HFD-fed rats in groups B, C and D had significant irregularity in estrous cyclicity Vs group A (p = 0.001, 0.003 and 0.034 respectively). Groups C and D had significant reduction in serum progesterone level (p = 0.006 and 0.018 Vs A). Isocaloric restriction of HFD feeding significantly increased serum LH. Groups B and C had a significant increase in caspase-3 expression in the ovary (p < 0.001). Conclusions Ad libitum HFD interfered with the normal estrous cycle and enhanced apoptosis of luteal cells in obese female rats. The HFD restriction interfered with the normal estrous cycle and caused functional insufficiency of the corpus luteum in obese female rats. These results suggest that HFD feeding determinately affects female reproductive function independently of caloric intake. PMID:27478474

Drought affects abortion of reproductive organs by exacerbating developmentally driven processes via expansive growth and hydraulics.

PubMed

Turc, Olivier; Tardieu, François

2018-06-06

Abortion of reproductive organs is a major limiting factor of yield under water deficit, but is also a trait selected for by evolutionary processes. The youngest reproductive organs must be prone to abortion so older organs can finish their development in case of limited resources. Water deficit increases natural abortion via two developmentally driven processes, namely a signal from the first fertilized ovaries and a simultaneous arrest of the expansive growth of all ovaries at a precise stage. In maize (Zea mays) subjected to water deficits typically encountered in dryland agriculture, these developmental mechanisms account for 90% of drought-associated abortion and are irreversible 3 d after silk emergence. Consistently, transcripts and enzyme activities suggest that the molecular events associated with abortion affect expansive growth in silks whereas ovaries maintain a favourable carbon status. Abortion due to carbon starvation is only observed for severe drought scenarios occurring after silking. Both kinetic and genetic evidence indicates that vegetative and reproductive structures share a partly common hydraulic control of expansive growth. Hence, the control of expansive growth of reproductive structures probably has a prominent effect on abortion for mild water deficits occurring at flowering time, while carbon starvation dominates in severe post-flowering drought scenarios.

Daily affect and female sexual function.

PubMed

Kalmbach, David A; Pillai, Vivek

2014-12-01

The specific affective experiences related to changes in various aspects of female sexual function have received little attention as most prior studies have focused instead on the role of clinical mood and anxiety disorders and their influence on sexual dysfunction. We sought to understand the transaction between daily affect and female sexual function in effort to provide a more nuanced understanding of the interplay between affective and sexual experiences. The present study used a 2-week daily diary approach to examine same-day and temporal relations between positive and negative affect states and sexual function in young women. We examined the unique relations between positive (i.e., joviality, serenity, self-assurance) and negative (i.e., fear, sadness, hostility) affects and female sexual response (i.e., desire, subjective arousal, vaginal lubrication, orgasmic function, and sexual pain) while controlling for higher order sexual distress, depression, and anxiety, as well as age effects and daily menstruation. Analyses revealed different aspects of both positive and negative affects to be independently related to sexual response indices. Specifically, results indicated that joviality was related to same-day sexual desire and predicted increased desire the following day. This latter relation was partially mediated by sexual activity. Further, greater sexual desire predicted next-day calmness, which was partially mediated by sexual activity. Notably, fear was related to same-day subjective arousal, lubrication, orgasmic function, and vaginal pain, whereas poorer orgasmic function predicted greater next-day sadness. These findings describe the manner in which changes in affect correspond to variations in female sexual function, thus highlighting the inextricability of mental and sexual health. Further, these findings may offer insight into the progression of normative levels of affect and sexual function as they develop into comorbid depression, anxiety, and

Reproduction of Pseudocalanus newmani (Copepoda: Calanoida) is deleteriously affected by diatom blooms A field study

NASA Astrophysics Data System (ADS)

Halsband-Lenk, Claudia; Pierson, James J.; Leising, Andrew W.

2005-11-01

Copepod secondary production has traditionally been linked to the spring diatom bloom in temperate and high latitudes, but laboratory studies have recently challenged this view and have shown either reduced fecundity or viability of offspring when copepods were fed high concentrations of - mostly unialgal - diatoms. However, field evidence that diatoms affect copepod reproduction is still scarce. We analyzed the reproductive response of a common, small calanoid copepod of the boreal Pacific, Pseudocalanus newmani, to spring diatom blooms in Dabob Bay, a semi-enclosed fjord of Puget Sound, Washington, USA. Abundance patterns, egg production rates, egg hatching success, and naupliar viability of the egg-carrying copepod were examined between February and early May in the years 2002-2004. The population underwent strong variations in abundance during both years, with high abundance of all stages from February to mid-March, but dramatically decreasing individual numbers later in spring. A recovery to higher numbers occurred in July. While egg production rates were independent of chlorophyll concentrations, the reproductive success of P. newmani was negatively affected by certain phytoplankton bloom conditions. Hatching success and - more markedly - naupliar survival were reduced following peaks of Thalassiosira species that were producing anti-mitotic aldehydes, but were high during periods when phytoplankton blooms were more diverse or dominated by other prey taxa including diatoms. As a consequence, recruitment of the naupliar population was considerably affected by the Thalassiosira blooms. This study shows for the first time that the so-called diatom effect operates in nature when all prerequisites - (1) high concentration of aldehyde producers, (2) few prey alternatives, and (3) feeding of copepods on these algae - are given. However, the effect was transient in Dabob Bay and may be so in other pelagic ecosystems. It remains to discern the potential sources of

Brain serotonin, psychoactive drugs, and effects on reproduction.

PubMed

Ayala, María Elena

2009-12-01

Serotonin, a biogenic amine, is present in significant amounts in many structures of the CNS. It is involved in regulation of a wide variety of physiological functions, such as sensory and motor functions, memory, mood, and secretion of hormones including reproductive hormones. It has also been implicated in the etiology of a range of psychiatric disorders such as anxiety, depression, and eating disorders, along with other conditions such as obesity and migraine. While some drugs that affect serotonin, such as fenfluramine and fluoxetine, have been successfully used in treatment of a range of psychiatric diseases, others, such as the amphetamine analogues MDMA and METH, are potent psychostimulant drugs of abuse. Alterations in serotonergic neurons caused by many of these drugs are well characterized; however, little is known about the reproductive consequences of such alterations. This review evaluates the effects of drugs such as MDMA, pCA, fenfluramine, and fluoxetine on serotonergic transmission in the brain, examines the relationships of these drug effects with the neuroendocrine mechanisms modulating reproductive events such as gonadotropin secretion, ovulation, spermatogenesis, and sexual behavior in animal models, and discusses possible reproductive implications of these drugs in humans.

FACTORS AFFECTING REPRODUCTION AND THE IMPORTANCE OF ADULT SIZE ON REPRODUCTIVE OUTPUT OF THE MIDGE, CHIRONOMUS TENTANS

EPA Science Inventory

Incorporating reproductive endpoints into sediment toxicity tests has become an important consideration in ecological risk assessments. The capacity to assess reproduction was one of the primary objectives underlying the recent development of a life-cycle test with the midge, Ch...

The environment and male reproduction: The effect of cadmium exposure on reproductive function and its implication in fertility.

PubMed

de Angelis, Cristina; Galdiero, Mariano; Pivonello, Claudia; Salzano, Ciro; Gianfrilli, Daniele; Piscitelli, Prisco; Lenzi, Andrea; Colao, Annamaria; Pivonello, Rosario

2017-10-01

Cadmium is an environmental pollutant known as endocrine disruptor. Testis is particularly susceptible to cadmium, and testis injury occurs at high but even low levels of exposure. Cadmium reproductive toxicity is mediated by multiple mechanisms, including structural damage to testis vasculature and blood-testis barrier, inflammation, cytotoxicity on Sertoli and Leydig cells, oxidative stress mainly by means of mimicry and interference with essential ions, apoptosis, interference with selected signaling pathways and epigenetic regulation of genes involved in the regulation of reproductive function, and disturbance of the hypothalamus-pituitary-gonadal axis. The current review outlines epidemiological observational findings from environmental and occupational exposure in humans, and reports experimental studies in humans and animals. Lastly, a focus on the pathogenetic mechanisms of cadmium toxicity and on the specific mechanisms of cadmium sensitivity and resistance, particularly assessed in animal models, is included. Despite convincing experimental findings in animals and supporting evidences in humans identifying cadmium as reproductive toxicant, observational findings are controversial, suffering from heterogeneity of study design and pattern of exposure, and from co-exposure to multiple pollutants. Copyright © 2017 Elsevier Inc. All rights reserved.

Reproductive factors affecting the bone mineral density in postmenopausal women.

PubMed

Ozdemir, Ferda; Demirbag, Derya; Rodoplu, Meliha

2005-03-01

Osteoporosis has been defined as a metabolic bone disease characterized by a loss of bone mineral density (BMD) greater than 2.5 standard deviations below young adult peak bone mass or the presence of fracture. By considering that some factors related to female reproductive system might influence the ultimate risk of osteoporosis, we aimed to investigate if a relationship exists between the present BMD of postmenopausal women with their past and present reproductive characteristics. The present study focused on how BMD could be affected by the following factors in postmenopausal women, such as age at menarche, age at first pregnancy, the number of pregnancies and total breast-feeding time. We reviewed detailed demographic history of 303 postmenopausal women. According to the results of the present study, a negative correlation was found between the number of parities and BMD. The BMD values decreased as the number of pregnancies increased. When the BMD values for lumbar vertebrae 2 and Ward's triangle were investigated, it was observed that a significant difference exists between the women with no child birth and those with more than five parities. There was a significant relationship between age at first pregnancy and BMD values at the lumbar vertebrae 2 and Ward's triangle. Women who had five or more abortions were found to have significantly lower spine BMD values compared to women who had no abortions or women who had one or two abortions. These findings indicate that the increased risk of osteoporosis is associated with the increased number of pregnancies and abortions and higher age at first pregnancy.

Effect of electromagnetic waves on human reproduction.

PubMed

Wdowiak, Artur; Mazurek, Paweł A; Wdowiak, Anita; Bojar, Iwona

2017-03-31

Electromagnetic radiation (EMR) emitting from the natural environment, as well as from the use of industrial and everyday appliances, constantly influence the human body. The effect of this type of energy on living tissues may exert various effects on their functioning, although the mechanisms conditioning this phenomenon have not been fully explained. It may be expected that the interactions between electromagnetic radiation and the living organism would depend on the amount and parameters of the transmitted energy and type of tissue exposed. Electromagnetic waves exert an influence on human reproduction by affecting the male and female reproductive systems, the developing embryo, and subsequently, the foetus. Knowledge concerning this problem is still being expanded; however, all the conditionings of human reproduction still remain unknown. The study presents the current state of knowledge concerning the problem, based on the latest scientific reports.

Selection on plant male function genes identifies candidates for reproductive isolation of yellow monkeyflowers.

PubMed

Aagaard, Jan E; George, Renee D; Fishman, Lila; Maccoss, Michael J; Swanson, Willie J

2013-01-01

Understanding the genetic basis of reproductive isolation promises insight into speciation and the origins of biological diversity. While progress has been made in identifying genes underlying barriers to reproduction that function after fertilization (post-zygotic isolation), we know much less about earlier acting pre-zygotic barriers. Of particular interest are barriers involved in mating and fertilization that can evolve extremely rapidly under sexual selection, suggesting they may play a prominent role in the initial stages of reproductive isolation. A significant challenge to the field of speciation genetics is developing new approaches for identification of candidate genes underlying these barriers, particularly among non-traditional model systems. We employ powerful proteomic and genomic strategies to study the genetic basis of conspecific pollen precedence, an important component of pre-zygotic reproductive isolation among yellow monkeyflowers (Mimulus spp.) resulting from male pollen competition. We use isotopic labeling in combination with shotgun proteomics to identify more than 2,000 male function (pollen tube) proteins within maternal reproductive structures (styles) of M. guttatus flowers where pollen competition occurs. We then sequence array-captured pollen tube exomes from a large outcrossing population of M. guttatus, and identify those genes with evidence of selective sweeps or balancing selection consistent with their role in pollen competition. We also test for evidence of positive selection on these genes more broadly across yellow monkeyflowers, because a signal of adaptive divergence is a common feature of genes causing reproductive isolation. Together the molecular evolution studies identify 159 pollen tube proteins that are candidate genes for conspecific pollen precedence. Our work demonstrates how powerful proteomic and genomic tools can be readily adapted to non-traditional model systems, allowing for genome-wide screens towards the

2.45-GHz microwave irradiation adversely affects reproductive function in male mouse, Mus musculus by inducing oxidative and nitrosative stress.

PubMed

Shahin, S; Mishra, V; Singh, S P; Chaturvedi, C M

2014-05-01

Electromagnetic radiations are reported to produce long-term and short-term biological effects, which are of great concern to human health due to increasing use of devices emitting EMR especially microwave (MW) radiation in our daily life. In view of the unavoidable use of MW emitting devices (microwaves oven, mobile phones, Wi-Fi, etc.) and their harmful effects on biological system, it was thought worthwhile to investigate the long-term effects of low-level MW irradiation on the reproductive function of male Swiss strain mice and its mechanism of action. Twelve-week-old mice were exposed to non-thermal low-level 2.45-GHz MW radiation (CW for 2 h/day for 30 days, power density = 0.029812 mW/cm(2) and SAR = 0.018 W/Kg). Sperm count and sperm viability test were done as well as vital organs were processed to study different stress parameters. Plasma was used for testosterone and testis for 3β HSD assay. Immunohistochemistry of 3β HSD and nitric oxide synthase (i-NOS) was also performed in testis. We observed that MW irradiation induced a significant decrease in sperm count and sperm viability along with the decrease in seminiferous tubule diameter and degeneration of seminiferous tubules. Reduction in testicular 3β HSD activity and plasma testosterone levels was also noted in the exposed group of mice. Increased expression of testicular i-NOS was observed in the MW-irradiated group of mice. Further, these adverse reproductive effects suggest that chronic exposure to nonionizing MW radiation may lead to infertility via free radical species-mediated pathway.

Age factors potentiating drug toxicity in the reproductive axis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Walker, R.F.

Traditionally, the drug toxicity in the reproductive system has been a concern only as it affects fertility and fecundity in young individuals. The purpose of this report is to address the potential problem of synergy between drug actions and abnormal secretion of reproductive hormones that together produce disease in older individuals. Thus, reproductive toxicity has different, but no less serious implications in aging individuals. During aging, the coordinated function of elements within the reproductive neuroendocrine axis degrades. This change promotes atypical secretion of hormones producing abnormal responses in target organs and thus creates a condition with pathogenic potential. Certain drugsmore » may contribute to reproductive toxicity in aging individuals either by accelerating the process of dysregulation and/or by synergizing with hormones to stimulate pathologic changes in target tissues. The geriatric population or the world is increasing, and since it consumes a proportionately larger percentage of drugs than younger groups, this novel form of reproductive toxicity may represent a problem in drug safety that warrants serious consideration.« less

Role of hormonal and inflammatory alterations in obesity-related reproductive dysfunction at the level of the hypothalamic-pituitary-ovarian axis.

PubMed

Goldsammler, Michelle; Merhi, Zaher; Buyuk, Erkan

2018-05-09

Besides being a risk factor for multiple metabolic disorders, obesity could affect female reproduction. While increased adiposity is associated with hormonal changes that could disrupt the function of the hypothalamus and the pituitary, compelling data suggest that obesity-related hormonal and inflammatory changes could directly impact ovarian function. To review the available data related to the mechanisms by which obesity, and its associated hormonal and inflammatory changes, could affect the female reproductive function with a focus on the hypothalamic-pituitary-ovarian (HPO) axis. PubMed database search for publications in English language until October 2017 pertaining to obesity and female reproductive function was performed. The obesity-related changes in hormone levels, in particular leptin, adiponectin, ghrelin, neuropeptide Y and agouti-related protein, are associated with reproductive dysfunction at both the hypothalamic-pituitary and the ovarian levels. The pro-inflammatory molecules advanced glycation end products (AGEs) and monocyte chemotactic protein-1 (MCP-1) are emerging as relatively new players in the pathophysiology of obesity-related ovarian dysfunction. There is an intricate crosstalk between the adipose tissue and the inflammatory system with the HPO axis function. Understanding the mechanisms behind this crosstalk could lead to potential therapies for the common obesity-related reproductive dysfunction.

Benefits and risks of ovarian function and reproduction for cancer development and prevention.

PubMed

Schindler, Adolf E

2011-12-01

Ovarian function and menstrual cycle disturbances, pregnancy, and reproductive medicine procedures can either increase gynecological cancer risk or prevent cancer development. For ovarian cancer development, there are two hypotheses, which are connected with ovulation and gonadotropin secretion. Most of the ovarian cancers seem to be derived from displaced ovarian surfice epithelial cells. One year of ovulatory cycles increases the ovarian cancer risk by 6%. Ovulation between 22 and 29 years of age causes the highest risk increase per year. In contrast, progesterone or progestins appear to create protection. Lifestyle can affect or modify ovarian cancer risk. Breast cancer risk is very much related to age of menarche and menopause, pregnancy, and breast feeding. All of which are related to ovarian function and progestogenic impact that translates either into breast cancer risk increase or decrease. This is modified by body mass index, physical activity, and lifestyle in general. The risk of endometrial cancer is most closely related to endogenous progesterone during the menstrual cycle and pregnancy or by exogenous progestogens as in oral contraceptives. These effects are progestogen dose and time dependent. Endometrial cancer risk can also be increased by estrogen-producing tumors or long-term estrogen treatment.

Advances in human reproductive ecology.

PubMed

Ellison, P T

1994-01-01

Human reproductive ecology pertains to reproduction biology and changes due to environmental influences. The research literature relies on clinical, epidemiological, and demographic analysis. The emphasis is on normal, nonpathological states and a broad range of ecological conditions. This review focused on the importance of age and energetic stress from ecological conditions rather than dieting or self-directed exercise in changing female fecundity. The literature on male reproductive ecology is still small but growing. J.W. Wood provided a comprehensive overview of the field. Natural fertility, as defined by Henry, is the lack of parity-specific fertility limitation. There is evidence that fertility can vary widely in natural fertility populations. There are consistent age patterns among different natural fertility populations. Doring found that there was higher frequency of anovulatory and luteal insufficiency in cycles during perimenarche and perimenopausal periods. Infertility studies have shown declines in pregnancy rates in women over the age of 30 years. Ovum donation evaluations have found both uterine age and ovarian and oocyte age to be related to the probability of a successful pregnancy. Basal follicle stimulating hormone and the endometrial thickness are important predictors of ovarian capacity and related to age and declining fecundity. Much of the literature on fecundity is derived from women with impaired reproductive physiology. In Lipson and Ellison's study of healthy women, average follicular and average luteal estradiol values declined with increasing subject age. Low follicular levels were correlated with smaller follicular size, low oocyte fertilizability, reduced endometrial thickness, and low pregnancy rates. Comparisons across populations have shown that populations experience declines in luteal function with age, but levels of luteal functions varied widely. Chronic conditions which slow growth and delay reproductive maturation may impact

Peroxisome Proliferator-Activated Receptors in Female Reproduction and Fertility

PubMed Central

Carta, Gaspare; Artini, Paolo Giovanni

2016-01-01

Reproductive functions may be altered by the exposure to a multitude of endogenous and exogenous agents, drug or environmental pollutants, which are known to affect gene transcription through the peroxisome proliferator-activated receptors (PPARs) activation. PPARs act as ligand activated transcription factors and regulate metabolic processes such as lipid and glucose metabolism, energy homeostasis, inflammation, and cell proliferation and differentiation. All PPARs isotypes are expressed along the hypothalamic-pituitary-gonadal axis and are strictly involved in reproductive functions. Since female fertility and energy metabolism are tightly interconnected, the research on female infertility points towards the exploration of potential PPARs activating/antagonizing compounds, mainly belonging to the class of thiazolidinediones (TZDs) and fibrates, as useful agents for the maintenance of metabolic homeostasis in women with ovarian dysfunctions. In the present review, we discuss the recent evidence about PPARs expression in the hypothalamic-pituitary-gonadal axis and their involvement in female reproduction. Finally, the therapeutic potential of their manipulation through several drugs is also discussed. PMID:27559343

Experimental reduction of intromittent organ length reduces male reproductive success in a bug

PubMed Central

Dougherty, Liam R.; Rahman, Imran A.; Burdfield-Steel, Emily R.; Greenway, E. V. (Ginny); Shuker, David M.

2015-01-01

It is now clear in many species that male and female genital evolution has been shaped by sexual selection. However, it has historically been difficult to confirm correlations between morphology and fitness, as genital traits are complex and manipulation tends to impair function significantly. In this study, we investigate the functional morphology of the elongate male intromittent organ (or processus) of the seed bug Lygaeus simulans, in two ways. We first use micro-computed tomography (micro-CT) and flash-freezing to reconstruct in high resolution the interaction between the male intromittent organ and the female internal reproductive anatomy during mating. We successfully trace the path of the male processus inside the female reproductive tract. We then confirm that male processus length influences sperm transfer by experimental ablation and show that males with shortened processi have significantly reduced post-copulatory reproductive success. Importantly, male insemination function is not affected by this manipulation per se. We thus present rare, direct experimental evidence that an internal genital trait functions to increase reproductive success and show that, with appropriate staining, micro-CT is an excellent tool for investigating the functional morphology of insect genitalia during copulation. PMID:25972470

The effects of oxidative stress on female reproduction: a review

PubMed Central

2012-01-01

Oxidative stress (OS), a state characterized by an imbalance between pro-oxidant molecules including reactive oxygen and nitrogen species, and antioxidant defenses, has been identified to play a key role in the pathogenesis of subfertility in both males and females. The adverse effects of OS on sperm quality and functions have been well documented. In females, on the other hand, the impact of OS on oocytes and reproductive functions remains unclear. This imbalance between pro-oxidants and antioxidants can lead to a number of reproductive diseases such as endometriosis, polycystic ovary syndrome (PCOS), and unexplained infertility. Pregnancy complications such as spontaneous abortion, recurrent pregnancy loss, and preeclampsia, can also develop in response to OS. Studies have shown that extremes of body weight and lifestyle factors such as cigarette smoking, alcohol use, and recreational drug use can promote excess free radical production, which could affect fertility. Exposures to environmental pollutants are of increasing concern, as they too have been found to trigger oxidative states, possibly contributing to female infertility. This article will review the currently available literature on the roles of reactive species and OS in both normal and abnormal reproductive physiological processes. Antioxidant supplementation may be effective in controlling the production of ROS and continues to be explored as a potential strategy to overcome reproductive disorders associated with infertility. However, investigations conducted to date have been through animal or in vitro studies, which have produced largely conflicting results. The impact of OS on assisted reproductive techniques (ART) will be addressed, in addition to the possible benefits of antioxidant supplementation of ART culture media to increase the likelihood for ART success. Future randomized controlled clinical trials on humans are necessary to elucidate the precise mechanisms through which OS affects female

Evaluation of reproductive function in Turkana women with enzyme immunoassays of urinary hormones in the field.

PubMed

Leslie, P W; Campbell, K L; Little, M A; Kigondu, C S

1996-02-01

The frequently reported observation that nomadic populations have lower fertility than their settled counterparts is often attributed to what are perceived as harsh, stressful conditions under which the nomads live. But the consequences of the hypothesized stresses for the reproductive biology or demography of these populations have been documented only a little. Traditionally, the Turkana of northwest Kenya are nomadic herders, but increasing numbers have settled on agricultural development schemes. We used an array of hormonal assays along with anthropometric indexes of nutritional status and interviews covering reproductive history, recent menstruation, diet, and health to compare reproductive function in nomadic and settled Turkana women. First morning urine samples were collected for three consecutive days during a series of surveys. Human choriogonadotropin (hCG; a marker for pregnancy), luteinizing hormone (LH; an indicator of ovulation), and pregnanediol glucuronide (PdG; an indicator of postovulatory luteal function) were assessed in the field with commercially available dipstick enzyme immunoassays. These assays along with the interview data allowed us to determine the reproductive status (e.g., pregnant or cycling, and if cycling, which phase of the ovarian cycle) of 166 nomadic and 194 settled Turkana women. The cross-sectional classifications allowed inferences of conception rates and normality of ovarian function. Follow-up surveys provided rates of pregnancy loss. Compared with the settled women, the nomadic women exhibited lower pregnancy rates and cycling nomadic women were less likely to show evidence of ovulation or luteal function. These results suggest that reproductive function of the nomadic women is diminished relative to the settled women. However, the settled women experienced a much higher rate of pregnancy loss, which may mean that their effective fecundability is in fact lower than that of the nomadic women. This study is the first to

Group management influences reproductive function of the male cheetah (Acinonyx jubatus).

PubMed

Koester, Diana C; Freeman, Elizabeth W; Wildt, David E; Terrell, Kimberly A; Franklin, Ashley D; Meeks, Karen; Crosier, Adrienne E

2017-03-01

Although the free-ranging cheetah is generally socially solitary, as many as 60% of males live in same-sex (usually sibling) coalitions. Under ex situ conditions, the cheetah experiences low reproductive success with only ~18% of males having ever produced young. Most male cheetahs (85%) are managed in captivity in coalitions, but with no data on the influence of social grouping on reproductive parameters. We examined the influence of singleton versus coalition management on various male cheetah physiological traits, including ejaculate quality and gonadal and adrenal hormone metabolite concentrations. We also assessed behaviour within coalitions for evidence of social hierarchy through initiation of interactions with group mates and relatedness to physiological traits. Ejaculate quality (including total motile and structurally normal spermatozoa per ejaculate) and androgen concentration profiles were higher (P<0.05) in coalition compared with singleton males. These results support the conclusion that testis function in the cheetah, specifically related to the development of normal, motile spermatozoa and androgen production, is influenced by management with same-sex conspecifics. The findings have implications for ex situ conservation breeding programs by suggesting that reproductive quality can be enhanced through group maintenance of cheetah males.

Female Reproductive Health After Childhood, Adolescent, and Young Adult Cancers: Guidelines for the Assessment and Management of Female Reproductive Complications

PubMed Central

Metzger, Monika L.; Meacham, Lillian R.; Patterson, Briana; Casillas, Jacqueline S.; Constine, Louis S.; Hijiya, Nobuko; Kenney, Lisa B.; Leonard, Marcia; Lockart, Barbara A.; Likes, Wendy; Green, Daniel M.

2013-01-01

Purpose As more young female patients with cancer survive their primary disease, concerns about reproductive health related to primary therapy gain relevance. Cancer therapy can often affect reproductive organs, leading to impaired pubertal development, hormonal regulation, fertility, and sexual function, affecting quality of life. Methods The Children's Oncology Group Long-Term Follow-Up Guidelines for Survivors of Childhood, Adolescent, and Young Adult Cancer (COG-LTFU Guidelines) are evidence-based recommendations for screening and management of late effects of therapeutic exposures. The guidelines are updated every 2 years by a multidisciplinary panel based on current literature review and expert consensus. Results This review summarizes the current task force recommendations for the assessment and management of female reproductive complications after treatment for childhood, adolescent, and young adult cancers. Experimental pretreatment as well as post-treatment fertility preservation strategies, including barriers and ethical considerations, which are not included in the COG-LTFU Guidelines, are also discussed. Conclusion Ongoing research will continue to inform COG-LTFU Guideline recommendations for follow-up care of female survivors of childhood cancer to improve their health and quality of life. PMID:23382474

How does health-promoting lifestyle relate to sexual function among women of reproductive age in Iran?

PubMed

Abedi, Parvin; Jorfi, Maryam; Afshari, Poorandokht; Fakhri, Ahmad

2017-08-01

This study aimed to evaluate the relation between health-promoting lifestyle and sexual function among women of reproductive age. In this cross-sectional study, 1200 women were recruited randomly from 10 public health centers in Ahvaz, Iran. A demographic questionnaire, Health Promoting Lifestyle Profile 2 (HPLP2), and Female Sexual Function Index (FSFI) were used for data collection. The inclusion criteria were as follows: women aged 15-45 years, married, monogamous, and having basic literacy. Data were analyzed using Kruskal-Wallis test, chi-square test, Spearman correlation coefficient, and logistic regression. All aspects of sexual function showed a significant relationship with different dimensions of HPLP2, except for pain and physical activity ( p < 0.001). Women who had better self-actualization were more likely to have better sexual function than other women (OR = 1.10, 95% CI: 1.06-1.14, p < 0.001). Other variables like responsibility, interpersonal relations and stress management also showed a significant correlation with sexual function. Results of this study showed that health-promoting lifestyle dimensions are significantly related to all aspects of sexual function in women of reproductive age. Health policy makers should take lifestyle-related factors of reproductive-aged women into account when seeking to improve the sexual wellbeing of this population. Further attention should also be given to assessing the direction of causality.

Influence of royal jelly on the reproductive function of puberty male rats.

PubMed

Yang, Anshu; Zhou, Ming; Zhang, Li; Xie, Guoxiu; Chen, Hongbing; Liu, Zhiyong; Ma, Wei

2012-06-01

The adverse effects of royal jelly on the reproductive system of puberty male rats were investigated. Royal jelly was daily administered by gavage to Sprague-Dawley rats at doses 200, 400, and 800 mg/kg for 4 weeks. The body weight and organ coefficients were determined. Sperm count, spermatozoa abnormality, and testicular histopathology were examined through light microscopy. Radioimmunoassay was used to detect serum hormones. The dietary exposure to royal jelly did not affect body weight, but the organ coefficients for the pituitary and testis in the high-dose group were decreased significantly compared with the control group, and significant changes in the microstructure of the testis were observed. No significant differences in sperm count were observed among all groups, however, the sperm deformity rate in the high-dose group increased significantly. Serum hormones in the high-dose group were significantly different from the control group. After royal jelly was stopped for 14 days, the adverse changes were partially reversed and returned to levels close to those in the control group. In conclusion, high-dose royal jelly oral administration for 4 weeks adversely affected the reproductive system of pubescent male rats, but the unfavorable effects are alleviated to some extent by cessation of administration. Copyright © 2012 Elsevier Ltd. All rights reserved.

Sustainability and factors affecting the success of community-based reproductive health programs in rural northwest Ethiopia.

PubMed

Argaw, Daniel; Fanthahun, Mesganaw; Berhane, Yemane

2007-08-01

arious Community-Based Reproductive Health interventions were initiated in many developing countries but their effectiveness has not been evaluated as much as needed. A comparative cross sectional study was carried out in February 2002 among women who participated in community based reproductive health interventions in South Gondar zone, Ethiopia. The study was conducted in eight kebeles taking successful and weak program areas for comparison. Both quantitative and qualitative methods were used for data collection. The qualitative method included key informants interview, and Focus Group Discussions with Community-based reproductive health agents (CBRHAs). A multistage sampling technique was employed to select 792 study subjects for the quantitative part of the study. Awareness of the presence of the CBRHA in the locality, participation in selection of the agents, acceptance of the agent, and evertalking to CBRHA about reproductive health issues were significantly higher in successful than in weak program areas [OR(95% CI) = 2.32 (1.74, 3.08), 3.28 (1.22, 9.27), 6.65 (3.59, 12.43), and 5.05 (3.22, 7.96), respectively]. In multiple logistic regression analysis awareness of presence of CBRHA in the village, acceptance of the CBRHA, and having had discussion with CBRHA maintained significant associations with type of community-based reproductive health program (successful/weak). Focus Group Discussions and Key Informant Interviews revealed better involvement of community leaders and health workers in the process of selecting and supervising CBRHA in successful areas compared to weak areas. The sustainability score of the Community-Based Reproductive Health Program (CBRHP) graded by the program coordinators was 2.92 out of 5. Acceptance of the CBRHAs, communication of the agents with community members, level of Support to the agents, better involvement of community representatives in the selection process were found to be the major factors affecting CBRHP. Overall

Impact of the environment on reproductive health.

PubMed

1991-01-01

damage is reported for fetuses and infants exposed to methyl mercury. There is the beginning of evidence that complications of pregnancy may be related to pollution levels surrounding industrial plants. Reproductive health is affected through chromosome damage and cell destruction, prenatal death, altered growth, fetal abnormalities, postnatal death, functional learning deficits, and premature aging.

[Impact of end-stage renal disease and kidney transplantation on the reproductive system].

PubMed

Delesalle, A-S; Robin, G; Provôt, F; Dewailly, D; Leroy-Billiard, M; Peigné, M

2015-01-01

Chronic renal failure leads to many metabolic disorders affecting reproductive function. For men, hypergonadotropic hypogonadism, hyperprolactinemia, spermatic alterations, decreased libido and erectile dysfunction are described. Kidney transplantation improves sperm parameters and hormonal function within 2 years. But sperm alterations may persist with the use of immunosuppressive drugs. In women, hypothalamic-pituitary-ovarian axis dysfunction due to chronic renal failure results in menstrual irregularities, anovulation and infertility. After kidney transplantation, regular menstruations usually start 1 to 12 months after transplantation. Fertility can be restored but luteal insufficiency can persist. Moreover, 4 to 20% of women with renal transplantation suffer from premature ovarian failure syndrome. In some cases, assisted reproductive technologies can be required and imply risks of ovarian hyperstimulation syndrome and must be performed with caution. Pregnancy risks for mother, fetus and transplant are added to assisted reproductive technologies ones. Only 7 authors have described assisted reproductive technologies for patients with kidney transplantation. No cases of haemodialysis patients have been described yet. So, assisted reproductive technologies management requires a multidisciplinary approach with obstetrics, nephrology and reproductive medicine teams' agreement. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Selenium status affects selenoprotein expression, reproduction, and F₁ generation locomotor activity in zebrafish (Danio rerio).

PubMed

Penglase, Sam; Hamre, Kristin; Rasinger, Josef D; Ellingsen, Staale

2014-06-14

Se is an essential trace element, and is incorporated into selenoproteins which play important roles in human health. Mammalian selenoprotein-coding genes are often present as paralogues in teleost fish, and it is unclear whether the expression patterns or functions of these fish paralogues reflect their mammalian orthologues. Using the model species zebrafish (Danio rerio; ZF), we aimed to assess how dietary Se affects key parameters in Se metabolism and utilisation including glutathione peroxidase (GPX) activity, the mRNA expression of key Se-dependent proteins (gpx1a, gpx1b, sepp1a and sepp1b), oxidative status, reproductive success and F1 generation locomotor activity. From 27 d until 254 d post-fertilisation, ZF were fed diets with graded levels of Se ranging from deficient ( < 0·10 mg/kg) to toxic (30 mg/kg). The mRNA expression of gpx1a and gpx1b and GPX activity responded in a similar manner to changes in Se status. GPX activity and mRNA levels were lowest when dietary Se levels (0·3 mg/kg) resulted in the maximum growth of ZF, and a proposed bimodal mechanism in response to Se status below and above this dietary Se level was identified. The expression of the sepp1 paralogues differed, with only sepp1a responding to Se status. High dietary Se supplementation (30 mg/kg) decreased reproductive success, while the offspring of ZF fed above 0·3 mg Se/kg diet had lower locomotor activity than the other groups. Overall, the novel finding of low selenoprotein expression and activity coinciding with maximum body growth suggests that even small Se-induced variations in redox status may influence cellular growth rates.

Reproduction Symposium: developmental programming of reproductive and metabolic health.

PubMed

Padmanabhan, V; Veiga-Lopez, A

2014-08-01

Inappropriate programming of the reproductive system by developmental exposure to excess steroid hormones is of concern. Sheep are well suited for investigating developmental origin of reproductive and metabolic disorders. The developmental time line of female sheep (approximately 5 mo gestation and approximately 7 mo to puberty) is ideal for conducting sequential studies of the progression of metabolic and/or reproductive disruption from the developmental insult to manifestation of adult consequences. Major benefits of using sheep include knowledge of established critical periods to target adult defects, a rich understanding of reproductive neuroendocrine regulation, availability of noninvasive approaches to monitor follicular dynamics, established surgical approaches to obtain hypophyseal portal blood for measurement of hypothalamic hormones, and the ability to perform studies in natural setting thereby keeping behavioral interactions intact. Of importance is the ability to chronically instrument fetus and mother for determining early endocrine perturbations. Prenatal exposure of the female to excess testosterone (T) leads to an array of adult reproductive disorders that include LH excess, functional hyperandrogenism, neuroendocrine defects, multifollicular ovarian morphology, and corpus luteum dysfunction culminating in early reproductive failure. At the neuroendocrine level, all 3 feedback systems are compromised. At the pituitary level, gonadotrope (LH secretion) sensitivity to GnRH is increased. Multifollicular ovarian morphology stems from persistence of follicles as well as enhanced follicular recruitment. These defects culminate in progressive loss of cyclicity and reduced fecundity. Prenatal T excess also leads to fetal growth retardation, an early marker of adult reproductive and metabolic diseases, insulin resistance, hypertension, and behavioral deficits. Collectively, the reproductive and metabolic deficits of prenatal T-treated sheep provide proof of

Regulation and roles of the hyaluronan system in mammalian reproduction.

PubMed

Fouladi-Nashta, Ali A; Raheem, Kabir A; Marei, Waleed F; Ghafari, Fataneh; Hartshorne, Geraldine M

2017-02-01

Hyaluronan (HA) is a non-sulphated glycosaminoglycan polymer naturally occurring in many tissues and fluids of mammals, including the reproductive system. Its biosynthesis by HA synthase (HAS1-3) and catabolism by hyaluronidases (HYALs) are affected by ovarian steroid hormones. Depending upon its molecular size, HA functions both as a structural component of tissues in the form of high-molecular-weight HA or as a signalling molecule in the form of small HA molecules or HA fragments with effects mediated through interaction with its specific cell-membrane receptors. HA is produced by oocytes and embryos and in various segments of the reproductive system. This review provides information about the expression and function of members of the HA system, including HAS, HYALs and HA receptors. We examine their role in various processes from folliculogenesis through oocyte maturation, fertilisation and early embryo development, to pregnancy and cervical dilation, as well as its application in assisted reproduction technologies. Particular emphasis has been placed upon the role of the HA system in pre-implantation embryo development and embryo implantation, for which we propose a hypothetical sequential model. © 2017 Society for Reproduction and Fertility.

Deletion of the Ttf1 gene in differentiated neurons disrupts female reproduction without impairing basal ganglia function.

PubMed

Mastronardi, Claudio; Smiley, Gregory G; Raber, Jacob; Kusakabe, Takashi; Kawaguchi, Akio; Matagne, Valerie; Dietzel, Anja; Heger, Sabine; Mungenast, Alison E; Cabrera, Ricardo; Kimura, Shioko; Ojeda, Sergio R

2006-12-20

Thyroid transcription factor 1 (TTF1) [also known as Nkx2.1 (related to the NK-2 class of homeobox genes) and T/ebp (thyroid-specific enhancer-binding protein)], a homeodomain gene required for basal forebrain morphogenesis, remains expressed in the hypothalamus after birth, suggesting a role in neuroendocrine function. Here, we show an involvement of TTF1 in the control of mammalian puberty and adult reproductive function. Gene expression profiling of the nonhuman primate hypothalamus revealed that TTF1 expression increases at puberty. Mice in which the Ttf1 gene was ablated from differentiated neurons grew normally and had normal basal ganglia/hypothalamic morphology but exhibited delayed puberty, reduced reproductive capacity, and a short reproductive span. These defects were associated with reduced hypothalamic expression of genes required for sexual development and deregulation of a gene involved in restraining puberty. No extrapyramidal impairments associated with basal ganglia dysfunction were apparent. Thus, although TTF1 appears to fulfill only a morphogenic function in the ventral telencephalon, once this function is satisfied in the hypothalamus, TTF1 remains active as part of the transcriptional machinery controlling female sexual development.

Divergence for residual feed intake of Holstein-Friesian cattle during growth did not affect production and reproduction during lactation.

PubMed

Macdonald, K A; Thomson, B P; Waghorn, G C

2016-11-01

Residual feed intake (RFI) is the difference between actual and predicted dry matter intake (DMI) of individual animals. Recent studies with Holstein-Friesian calves have identified an ~20% difference in RFI during growth (calf RFI) and these groups remained divergent in RFI during lactation. The objective of the experiment described here was to determine if cows selected for divergent RFI as calves differed in milk production, reproduction or in the profiles of BW and body condition score (BCS) change during lactation, when grazing pasture. The cows used in the experiment (n=126) had an RFI of -0.88 and +0.75 kg DM intake/day for growth as calves (efficient and inefficient calf RFI groups, respectively) and were intensively grazed at four stocking rates (SR) of 2.2, 2.6, 3.1 and 3.6 cows/ha on self-contained farmlets, over 3 years. Each SR treatment had equal number of cows identified as low and high calf RFI, with 24, 28, 34 and 40/11 ha farmlet. The cows divergent for calf RFI were randomly allocated to each SR. Although SR affected production, calf RFI group (low or high) did not affect milk production, reproduction, BW, BCS or changes in these parameters throughout lactation. The most efficient animals (low calf RFI) lost similar BW and BCS as the least efficient (high calf RFI) immediately post-calving, and regained similar BW and BCS before their next calving. These results indicate that selection for RFI as calves to increase efficiency of feed utilisation did not negatively affect farm productivity variables (milk production, BCS, BW and reproduction) as adults when managed under an intensive pastoral grazing system.

Ovarian function and reproductive senescence in the rat: role of ovarian sympathetic innervation.

PubMed

Cruz, Gonzalo; Fernandois, Daniela; Paredes, Alfonso H

2017-02-01

Successful reproduction is the result of a myriad interactions in which the ovary and the ovarian follicular reserve play a fundamental role. At present, women who delay maternity until after 30 years of age have a decreased fertility rate due to various causes, including damaged follicles and a reduction in the reserve pool of follicles. Therefore, the period just prior to menopause, also known as the subfertile period, is important. The possibility of modulating the follicular pool and the health of follicles during this period to improve fertility is worth exploring. We have developed an animal model to study the ovarian ageing process during this subfertile period to understand the mechanisms responsible for reproductive senescence. In the rat model, we have shown that the sympathetic nervous system participates in regulating the follicular development during ovarian ageing. This article reviews the existing evidence on the presence and functional role of sympathetic nerve activity in regulating the follicular development during ovarian ageing, with a focus on the subfertile period.Free Spanish abstract: A Spanish translation of this abstract is freely available at http://www.reproduction-online.org/content/153/2/R61/suppl/DC1. © 2017 Society for Reproduction and Fertility.

Nodavirus Colonizes and Replicates in the Testis of Gilthead Seabream and European Sea Bass Modulating Its Immune and Reproductive Functions

PubMed Central

Valero, Yulema; Arizcun, Marta; Esteban, M. Ángeles; Bandín, Isabel; Olveira, José G.; Patel, Sonal; Cuesta, Alberto; Chaves-Pozo, Elena

2015-01-01

Viruses are threatening pathogens for fish aquaculture. Some of them are transmitted through gonad fluids or gametes as occurs with nervous necrosis virus (NNV). In order to be transmitted through the gonad, the virus should colonize and replicate inside some cell types of this tissue and avoid the subsequent immune response locally. However, whether NNV colonizes the gonad, the cell types that are infected, and how the immune response in the gonad is regulated has never been studied. We have demonstrated for the first time the presence and localization of NNV into the testis after an experimental infection in the European sea bass (Dicentrarchus labrax), and in the gilthead seabream (Sparus aurata), a very susceptible and an asymptomatic host fish species, respectively. Thus, we localized in the testis viral RNA in both species using in situ PCR and viral proteins in gilthead seabream by immunohistochemistry, suggesting that males might also transmit the virus. In addition, we were able to isolate infective particles from the testis of both species demonstrating that NNV colonizes and replicates into the testis of both species. Blood contamination of the tissues sampled was discarded by completely fish bleeding, furthermore the in situ PCR and immunocytochemistry techniques never showed staining in blood vessels or cells. Moreover, we also determined how the immune and reproductive functions are affected comparing the effects in the testis with those found in the brain, the main target tissue of the virus. Interestingly, NNV triggered the immune response in the European sea bass but not in the gilthead seabream testis. Regarding reproductive functions, NNV infection alters 17β-estradiol and 11-ketotestosterone production and the potential sensitivity of brain and testis to these hormones, whereas there is no disruption of testicular functions according to several reproductive parameters. Moreover, we have also studied the NNV infection of the testis in vitro to

Factors affecting parent-adolescent discussion on reproductive health issues in Harar, eastern Ethiopia: a cross-sectional study.

PubMed

Yadeta, Tesfaye Assebe; Bedane, Haji Kedir; Tura, Abera Kenay

2014-01-01

Open family discussion on reproductive health (RH) issues often leads to increased awareness on RH matters and reduces risky behaviors among adolescents. This study was conducted to assess factors affecting parent-adolescent discussion on RH issues in Harar, Ethiopia. A cross-sectional survey using face to face interview supplemented with focus group discussion (FGD) was conducted on 751 randomly selected parents of 10-19-year-old adolescents. Data was analyzed using SPSS version 15. More than one-fourth (28.76%) of parents reported discussing RH issues with their adolescents during the last six months. In the logistic regression, parents who have demonstrated good RH knowledge and positive attitude towards RH were almost six times and seventy percent (AOR 5.69, 95% CI: 3.67-8.82; AOR 1.70, 95% CI: 1.08-2.68) higher in discussing RH with their adolescents than their counterparts, respectively. Parent-adolescent discussion about RH issues rarely occurs and is bounded by lack of knowledge, sociocultural norms, and parental concern that discussion would encourage premarital sex. Reproductive health programs should target on improving awareness of parents and addressing sociocultural norms surrounding reproductive health issues.

Perceived stress, reproductive hormones, and ovulatory function: a prospective cohort study

PubMed Central

Schliep, Karen C.; Mumford, Sunni L.; Vladutiu, Catherine J.; Ahrens, Katherine A.; Perkins, Neil J.; Sjaarda, Lindsey A.; Kissell, Kerri A.; Prasad, Ankita; Wactawski-Wende, Jean; Schisterman, Enrique F.

2014-01-01

Background Stress has been shown to suppress ovulation in experimental models, but its effect on human reproduction at the population level is unclear. Methods Healthy women (n=259), aged 18–44 years from Western New York, were followed for two menstrual cycles (2005–2007). Women completed daily perceived stress assessments, a 4-item Perceived Stress Scale (PSS-4) up to four times each cycle, and a 14-item PSS at baseline. Mixed model analyses were used to assess effects of stress on log reproductive hormone concentrations and sporadic anovulation. Results High versus low daily stress was associated with lower estradiol (-9.5%; 95% confidence interval (CI)= -15.6% to -3.0%), free estradiol (-10.4% [-16.5% to -3.9%]), and LH (-14.8% = [-21.3% to -7.7%]), and higher FSH (6.2% [2.0% to 10.5%]) after adjusting for age, race, percent body fat, depression score, and time-varying hormones and vigorous exercise. High versus low daily stress was also associated with lower luteal progesterone (-10.4% [-19.7% to -0.10%]) and higher odds of anovulation (adjusted OR = 2.2 [95% CI=1.0 to 4.7]). For each unit increase in daily stress level, women had a 70% higher odds of an anovulatory episode (OR=1.7 [1.1 to 2.4]). Similar but attenuated results were found for the association between the PSS-4 and reproductive hormones, while null findings were found for the baseline PSS. Conclusion Daily perceived stress does appear to interfere with menstrual cycle function among women with no known reproductive disorders, warranting further research to explore potential population-level impacts and causal biologic mechanisms. PMID:25643098

A role for tachykinins in female mouse and rat reproductive function.

PubMed

Pintado, C Oscar; Pinto, Francisco M; Pennefather, Jocelyn N; Hidalgo, Agustin; Baamonde, Ana; Sanchez, Teresa; Candenas, M Luz

2003-09-01

Tachykinins may be involved in reproduction. A reverse transcription-polymerase chain reaction assay was used to analyze the expression of tachykinins and tachykinin receptors in different types of reproductive cells from mice. The preprotachykinin (PPT) genes, PPT-A, PPT-B and PPT-C, that encode substance P/neurokinin A, neurokinin B, and hemokinin-1, respectively, and the genes that encode the tachykinin NK1, NK2, and NK3 receptors were all expressed, at different levels, in the uterus of superovulated, unfertilized mice. The mRNA of neprilysin (NEP), the main enzyme involved in tachykinin metabolism, was also expressed in the uterus. Isolated cumulus granulosa cells expressed PPT-A, PPT-B, PPT-C, and NEP and low levels of the tachykinin NK1 and NK2 receptors. Mouse oocytes expressed PPT-A and -B mRNA transcripts. A low expression of the three tachykinin receptors was observed but PPT-C and NEP were undetectable. Two- and 8- to 16-cell mouse embryos expressed only a low-abundance transcript corresponding to the NK1 receptor. However, the mRNAs of PPT-B, PPT-C and NEP appeared in blastocyst-stage embryos. A low-abundance transcript corresponding to the NK2 receptor was the only target gene detected in mice sperm. Female mice or rats treated neonatally with capsaicin showed a reduced fertility. A reduction in litter size was observed in female rats treated in vivo with the tachykinin NK3 receptor antagonist SR 142801. These data show that tachykinins of both neuronal and nonneuronal origin are differentially expressed in various types of reproductive cells and may play a role in female reproductive function.

Learning speed is affected by personality and reproductive investment in a songbird

PubMed Central

Martens, Tine; Pinxten, Rianne; Eens, Marcel

2017-01-01

Individuals from different taxa, including songbirds, differ consistently in behaviour and personality when facing different situations. Although our understanding of animal behaviour has increased, knowledge about between-individual differences in cognitive abilities is still limited. By using an experimental approach and a free-living songbird (Parus major) as a model, we attempted to understand between-individual differences in habituation to playbacks (as a proxy of learning speed), by investigating the role of personality, age and reproductive investment (clutch size). Pre-breeding males were tested for exploration (a proxy of personality) in standardized conditions. In addition, the same individuals were exposed to three playbacks in the field during incubation. Birds significantly moved less, stayed further away and overlapped less the playback with successive playback stimulation. While a decrease in the locomotor behaviour can be explained by personality, differences in habituation of overlapping were predicted by both reproductive investment and personality. Fast explorers habituated less. Moreover, males paired to females with larger clutches did not vary the intensity of overlapping. Since habituation requires information for recognition of non-threatening signals, personality may bias information gathering. While fast explorers may collect less information from the environment, slow explorers (reactive birds) seem to pay attention to environmental clues and collect detailed information. We provided evidence that the rate of habituation of behavioural responses, a proxy of cognitive abilities, may be affected by different factors and in a complex way. PMID:29020028

Learning speed is affected by personality and reproductive investment in a songbird.

PubMed

Rivera-Gutierrez, Hector Fabio; Martens, Tine; Pinxten, Rianne; Eens, Marcel

2017-01-01

Individuals from different taxa, including songbirds, differ consistently in behaviour and personality when facing different situations. Although our understanding of animal behaviour has increased, knowledge about between-individual differences in cognitive abilities is still limited. By using an experimental approach and a free-living songbird (Parus major) as a model, we attempted to understand between-individual differences in habituation to playbacks (as a proxy of learning speed), by investigating the role of personality, age and reproductive investment (clutch size). Pre-breeding males were tested for exploration (a proxy of personality) in standardized conditions. In addition, the same individuals were exposed to three playbacks in the field during incubation. Birds significantly moved less, stayed further away and overlapped less the playback with successive playback stimulation. While a decrease in the locomotor behaviour can be explained by personality, differences in habituation of overlapping were predicted by both reproductive investment and personality. Fast explorers habituated less. Moreover, males paired to females with larger clutches did not vary the intensity of overlapping. Since habituation requires information for recognition of non-threatening signals, personality may bias information gathering. While fast explorers may collect less information from the environment, slow explorers (reactive birds) seem to pay attention to environmental clues and collect detailed information. We provided evidence that the rate of habituation of behavioural responses, a proxy of cognitive abilities, may be affected by different factors and in a complex way.

Gap junction connexins in female reproductive organs: implications for women's reproductive health.

PubMed

Winterhager, Elke; Kidder, Gerald M

2015-01-01

Connexins comprise a family of ~20 proteins that form intercellular membrane channels (gap junction channels) providing a direct route for metabolites and signalling molecules to pass between cells. This review provides a critical analysis of the evidence for essential roles of individual connexins in female reproductive function, highlighting implications for women's reproductive health. No systematic review has been carried out. Published literature from the past 35 years was surveyed for research related to connexin involvement in development and function of the female reproductive system. Because of the demonstrated utility of genetic manipulation for elucidating connexin functions in various organs, much of the cited information comes from research with genetically modified mice. In some cases, a distinction is drawn between connexin functions clearly related to the formation of gap junction channels and those possibly linked to non-channel roles. Based on work with mice, several connexins are known to be required for female reproductive functions. Loss of connexin43 (CX43) causes an oocyte deficiency, and follicles lacking or expressing less CX43 in granulosa cells exhibit reduced growth, impairing fertility. CX43 is also expressed in human cumulus cells and, in the context of IVF, has been correlated with pregnancy outcome, suggesting that this connexin may be a determinant of oocyte and embryo quality in women. Loss of CX37, which exclusively connects oocytes with granulosa cells in the mouse, caused oocytes to cease growing without acquiring meiotic competence. Blocking of CX26 channels in the uterine epithelium disrupted implantation whereas loss or reduction of CX43 expression in the uterine stroma impaired decidualization and vascularization in mouse and human. Several connexins are important in placentation and, in the human, CX43 is a key regulator of the fusogenic pathway from the cytotrophoblast to the syncytiotrophoblast, ensuring placental growth

Reproductive hormones and menstrual changes with exercise in female athletes.

PubMed

Arena, B; Maffulli, N; Maffulli, F; Morleo, M A

1995-04-01

The endocrine equilibrium which regulates reproductive function in women can be affected by physical and psychological factors. Blood levels of hormones depend on a balance between production, metabolism and clearance rates. Intensive physical exercise may affect this balance via different mechanisms, such as stress associated with competition, dieting, reduction of body fat and body weight, production of heat or hypoxia. Women who engage in regular high intensity exercise may be at risk, as a consequence of these hormonal changes, of developing menstrual disturbances such as oligomenorrhoea, delayed menarche and amenorrhoea. Impaired production of gonadotrophins, which leads to luteal phase deficiency and anovulation, is a common hormonal finding with exercise-induced menstrual disturbances, but several other hormones may show significant alterations. In this article we have reviewed the recent literature on the effects of intensive physical exercise on the menstrual cycle, on some important physical parameters such as bone mineral density and bodyweight, and on those hormones (gonadotrophins, prolactin, melatonin, opioid peptides and steroids) which regulate, directly or indirectly, the reproductive function in women.

[Effects of bisphenol A on the placental function and reproduction in rats].

PubMed

Lee, Chae-Kwan; Kim, Seog-Hyun; Moon, Deog-Hwan; Kim, Jeong-Ho; Son, Byung-Chul; Kim, Dae-Hwan; Lee, Chang-Hee; Kim, Hwi-Dong; Kim, Jung-Won; Kim, Jong-Eun; Lee, Chae-Un

2005-08-01

The aim of this study was to investigate the effects of bisphenol A (BPA), an estrogen-like environmental endocrine disrupter, on the placental function and reproduction in rats. The mRNA levels of the placental prolactin-growth hormone(PRL-GH) gene family, placental trophoblast cell frequency and reproductive data were analyzed. The pregnancies of F344 Fisher rats (160 g +/-20 g) were detected by the presence of the copulatory plug or sperm in the vaginal smear, which marked Day 0 of pregnancy. Pregnant rats were divided into three groups. The control group was intraperitoneally injected with a sesame oil vehicle. The two remaining groups were injected with 50 or 500 mg/kg B.W/day of BPA, resuspended in sesame oil, on either days 7 to 11 or 16 to 20 of pregnancy, with the rats sacrificed on either day 11 or 20, respectively. The mRNA levels of PRL-GH and Pit-1a and b isotype genes were analyzed by Northern blot hybridization and reverse transcription-polymerase chain reaction. The hormone concentrations were analyzed by radioimmunoassay, and the frequency of the placental trophoblast cells observed by a histochemical study. Reproductive data, such as the placental weight and litter size, were surveyed on day 20. The fetal weight was surveyed for 4 weeks after birth. A statistical analysis was carried out using the SAS program (version 8.1). The mRNA levels of the PRL-GH gene family, such as placental lactogen I, Iv and II, prolactin like protein A, C and Cv, and decidual prolactin-related protein were significantly reduced due to BPA exposure. The mRNA levels of the Pit-1a and b isotype genes, which induce the expression of the PRL-GH gene family in the rat placenta, were also reduced due to BPA exposure. The PL-Iv and PL-II concentrations were reduced in the BPA exposed group. During the middle to last stage of pregnancy (Days 11-20), a high dose of BPA exposure reduced the frequency of spongiotrophoblast cells, which are responsible for the secretion of the PRL

Functional Significance of GnRH and Kisspeptin, and Their Cognate Receptors in Teleost Reproduction

PubMed Central

Gopurappilly, Renjitha; Ogawa, Satoshi; Parhar, Ishwar S.

2012-01-01

Guanine nucleotide binding protein (G-protein)-coupled receptors (GPCRs) are eukaryotic transmembrane proteins found in all living organisms. Their versatility and roles in several physiological processes make them the single largest family of drug targets. Comparative genomic studies using various model organisms have provided useful information about target receptors. The similarity of the genetic makeup of teleosts to that of humans and other vertebrates aligns with the study of GPCRs. Gonadotropin-releasing hormone (GnRH) represents a critical step in the reproductive process through its cognate GnRH receptors (GnRHRs). Kisspeptin (Kiss1) and its cognate GPCR, GPR54 (=kisspeptin receptor, Kiss-R), have recently been identified as a critical signaling system in the control of reproduction. The Kiss1/Kiss-R system regulates GnRH release, which is vital to pubertal development and vertebrate reproduction. This review highlights the physiological role of kisspeptin-Kiss-R signaling in the reproductive neuroendocrine axis in teleosts through the modulation of GnRH release. Moreover, we also review the recent developments in GnRHR and Kiss-R with respect to their structural variants, signaling mechanisms, ligand interactions, and functional significance. Finally, we discuss the recent progress in identifying many teleost GnRH-GnRHR and kisspeptin-Kiss-R systems and consider their physiological significance in the control of reproduction. PMID:23482509

Functional significance of GnRH and kisspeptin, and their cognate receptors in teleost reproduction.

PubMed

Gopurappilly, Renjitha; Ogawa, Satoshi; Parhar, Ishwar S

2013-01-01

Guanine nucleotide binding protein (G-protein)-coupled receptors (GPCRs) are eukaryotic transmembrane proteins found in all living organisms. Their versatility and roles in several physiological processes make them the single largest family of drug targets. Comparative genomic studies using various model organisms have provided useful information about target receptors. The similarity of the genetic makeup of teleosts to that of humans and other vertebrates aligns with the study of GPCRs. Gonadotropin-releasing hormone (GnRH) represents a critical step in the reproductive process through its cognate GnRH receptors (GnRHRs). Kisspeptin (Kiss1) and its cognate GPCR, GPR54 (=kisspeptin receptor, Kiss-R), have recently been identified as a critical signaling system in the control of reproduction. The Kiss1/Kiss-R system regulates GnRH release, which is vital to pubertal development and vertebrate reproduction. This review highlights the physiological role of kisspeptin-Kiss-R signaling in the reproductive neuroendocrine axis in teleosts through the modulation of GnRH release. Moreover, we also review the recent developments in GnRHR and Kiss-R with respect to their structural variants, signaling mechanisms, ligand interactions, and functional significance. Finally, we discuss the recent progress in identifying many teleost GnRH-GnRHR and kisspeptin-Kiss-R systems and consider their physiological significance in the control of reproduction.

[Toxicological characteristics of Ochratoxin A and its impact on male reproduction].

PubMed

Zhang, Tian-Yu; Zhao, Yong; Li, Lan; Shen, Wei

2017-08-01

Ochratoxin A (OTA) is found not only nephrotoxic, teratogenic, neurotoxic, and immunotoxic, but also reprotoxic for human and animals. In the recent decade, more attention has been paid to the impact of OTA on human reproduction and the studies of its underlying mechanisms. Many studies show that OTA affects the function of the reproductive system by acting as an endocrine disrupter and, as a testicular toxin, decreases sperm quality and even induces testis cancer. This review summarizes the toxicological characteristics and toxicokinetic process of OTA as well as recent progress in the studies of various toxic effects of OTA and their underlying mechanisms, hoping to call the attention from more people to the toxicity of OTA to male reproductive health.

Nutrient restriction induces failure of reproductive function and molecular changes in hypothalamus-pituitary-gonadal axis in postpubertal gilts.

PubMed

Zhou, Dongsheng; Zhuo, Yong; Che, Lianqiang; Lin, Yan; Fang, Zhengfeng; Wu, De

2014-07-01

People on a diet to lose weight may be at risk of reproductive failure. To investigate the effects of nutrient restriction on reproductive function and the underlying mechanism, changes of reproductive traits, hormone secretions and gene expressions in hypothalamus-pituitary-gonadal axis were examined in postpubertal gilts at anestrus induced by nutrient restriction. Gilts having experienced two estrus cycles were fed a normal (CON, 2.86 kg/d) or nutrient restricted (NR, 1 kg/d) food regimens to expect anestrus. NR gilts experienced another three estrus cycles, but did not express estrus symptoms at the anticipated fourth estrus. Blood samples were collected at 5 days' interval for consecutive three times for measurement of hormone concentrations at the 23th day of the fourth estrus cycle. Individual progesterone concentrations of NR gilts from three consecutive blood samples were below 1.0 ng/mL versus 2.0 ng/mL in CON gilts, which was considered anestrus. NR gilts had impaired development of reproductive tract characterized by absence of large follicles (diameter ≥ 6 mm), decreased number of corepus lutea and atrophy of uterus and ovary tissues. Circulating concentrations of IGF-I, kisspeptin, estradiol, progesterone and leptin were significantly lower in NR gilts than that in CON gilts. Nutrient restriction down-regulated gene expressions of kiss-1, G-protein coupled protein 54, gonadotropin-releasing hormone, estrogen receptor α, progesterone receptor, leptin receptor, follicle-stimulating hormone and luteinizing hormone and insulin-like growth factor I in hypothalamus-pituitary-gonadal axis of gilts. Collectively, nutrient restriction resulted in impairment of reproductive function and changes of hormone secretions and gene expressions in hypothalamus-pituitary-gonadal axis, which shed light on the underlying mechanism by which nutrient restriction influenced reproductive function.

Trace concentrations of imazethapyr (IM) affect floral organs development and reproduction in Arabidopsis thaliana: IM-induced inhibition of key genes regulating anther and pollen biosynthesis.

PubMed

Qian, Haifeng; Li, Yali; Sun, Chongchong; Lavoie, Michel; Xie, Jun; Bai, Xiaocui; Fu, Zhengwei

2015-01-01

Understanding how herbicides affect plant reproduction and growth is critical to develop herbicide toxicity model and refine herbicide risk assessment. Although our knowledge of herbicides toxicity mechanisms at the physiological and molecular level in plant vegetative phase has increased substantially in the last decades, few studies have addressed the herbicide toxicity problematic on plant reproduction. Here, we determined the long-term (4-8 weeks) effect of a chiral herbicide, imazethapyr (IM), which has been increasingly used in plant crops, on floral organ development and reproduction in the model plant Arabidopsis thaliana. More specifically, we followed the effect of two IM enantiomers (R- and S-IM) on floral organ structure, seed production, pollen viability and the transcription of key genes involved in anther and pollen development. The results showed that IM strongly inhibited the transcripts of genes regulating A. thaliana tapetum development (DYT1: DYSFUNCTIONAL TAPETUM 1), tapetal differentiation and function (TDF1: TAPETAL DEVELOPMENT AND FUNCTION1), and pollen wall formation and developments (AMS: ABORTED MICROSPORES, MYB103: MYB DOMAIN PROTEIN 103, MS1: MALE STERILITY 1, MS2: MALE STERILITY 2). Since DYT1 positively regulates 33 genes involved in cell-wall modification (such as, TDF1, AMS, MYB103, MS1, MS2) that can catalyze the breakdown of polysaccharides to facilitate anther dehiscence, the consistent decrease in the transcription of these genes after IM exposure should hamper anther opening as observed under scanning electron microscopy. The toxicity of IM on anther opening further lead to a decrease in pollen production and pollen viability. Furthermore, long-term IM exposure increased the number of apurinic/apyrimidinic sites (AP sites) in the DNA of A. thaliana and also altered the DNA of A. thaliana offspring grown in IM-free soils. Toxicity of IM on floral organs development and reproduction was generally higher in the presence of the R

Predation risk affects growth and reproduction of an invasive snail and its lethal effect depends on prey size

PubMed Central

Guo, Jing; Martín, Pablo R.; Zhang, Chunxia

2017-01-01

The behavior of invasive species under predation risk has been studied extensively, but their growth and reproductive responses have rarely been investigated. We conducted experiments with juveniles and adults of the invasive freshwater snail Pomacea canaliculata, and we observed changes in growth and reproduction in response to predation risk from a caged predator (Trachemys scripta elegans). P. canaliculata produced eggs earlier in the presence of predators and injured conspecifics compared with the control group (no risk), although the total number of egg masses laid by per female was exceeded by that of the controls after 15 days. Egg hatching success noticeably decreased under predation risk, and the incubation period was significantly prolonged; however, the oviposition height of the snails was not affected. A lethal effect of predation risk was detected in juvenile snails but not in adults. The growth of juvenile P. canaliculata was inhibited under predation risk, probably due to a reduction in food intake. Adult females exhibited a greater reduction in growth under predation risk than males, which likely resulted in part from the high reproductive investment of females in egg laying. These results indicate that P. canaliculata snails under predation risk face a trade-off between predator avoidance and growth and reproduction, where the lethal effect of predation risk is linked to the size of the prey. PMID:29136660

Morphological and physiological changes during reproduction and their relationships to reproductive performance in a capital breeder.

PubMed

Stahlschmidt, Zachary R; Lourdais, Olivier; Lorioux, Sophie; Butler, Michael W; Davis, Jon R; Salin, Karine; Voituron, Yann; DeNardo, Dale F

2013-01-01

Current reproductive effort typically comes at a cost to future reproductive value by altering somatic function (e.g., growth or self-maintenance). Furthermore, effects of reproduction often depend on both fecundity and stage of reproduction, wherein allocation of resources into additional offspring and/or stages of reproduction results in increased costs. Despite these widely accepted generalities, interindividual variation in the effects of reproduction is common-yet the proximate basis that allows some individuals to mitigate these detrimental effects is unclear. We serially measured several variables of morphology (e.g., musculature) and physiology (e.g., antioxidant defenses) in female Children's pythons (Antaresia childreni) throughout reproduction to examine how these traits change over the course of reproduction and whether certain physiological traits are associated with reduced effects of reproduction in some individuals. Reproduction in this capital breeder was associated with changes in both morphology and physiology, but only morphological changes varied with fecundity and among specific reproductive stages. During reproduction, we detected negative relationships between morphology and self-maintenance (e.g., increased muscle allocation to reproduction was related to reduced immune function). Additionally, females that allocated resources more heavily into current reproduction also did so during future reproduction, and these females assimilated resources more efficiently, experienced reduced detriments to self-maintenance (e.g., lower levels of oxidative damage and glucocorticoids) during reproduction, and produced clutches with greater hatching success. Our results suggest that interindividual variation in specific aspects of physiology (assimilation efficiency and oxidative status) may drive variation in reproductive performance.

The regulation of reproductive neuroendocrine function by insulin and insulin-like growth factor-1 (IGF-1)

PubMed Central

Wolfe, Andrew; Divall, Sara; Wu, Sheng

2014-01-01

The mammalian reproductive hormone axis regulates gonadal steroid hormone levels and gonadal function essential for reproduction. The neuroendocrine control of the axis integrates signals from a wide array of inputs. The regulatory pathways important for mediating these inputs have been the subject of numerous studies. One class of proteins that have been shown to mediate metabolic and growth signals to the CNS includes Insulin and IGF-1. These proteins are structurally related and can exert endocrine and growth factor like action via related receptor tyrosine kinases. The role that insulin and IGF-1 play in controlling the hypothalamus and pituitary and their role in regulating puberty and nutritional control of reproduction has been studied extensively. This review summarizes the in vitro and in vivo models that have been used to study these neuroendocrine structures and the influence of these growth factors on neuroendocrine control of reproduction. PMID:24929098

Conditions during adulthood affect cohort-specific reproductive success in an Arctic-nesting goose population.

PubMed

Weegman, Mitch D; Bearhop, Stuart; Hilton, Geoff M; Walsh, Alyn; Fox, Anthony David

2016-01-01

Variation in fitness between individuals in populations may be attributed to differing environmental conditions experienced among birth (or hatch) years (i.e., between cohorts). In this study, we tested whether cohort fitness could also be explained by environmental conditions experienced in years post-hatch, using 736 lifelong resighting histories of Greenland white-fronted geese (Anser albifrons flavirostris) marked in their first winter. Specifically, we tested whether variation in age at first successful reproduction, the size of the first successful brood and the proportion of successful breeders by cohort was explained by environmental conditions experienced on breeding areas in west Greenland during hatch year, those in adulthood prior to successful reproduction and those in the year of successful reproduction, using North Atlantic Oscillation indices as proxies for environmental conditions during these periods. Fifty-nine (8%) of all marked birds reproduced successfully (i.e., were observed on wintering areas with young) only once in their lifetime and 15 (2%) reproduced successfully twice or thrice. Variation in age at first successful reproduction was explained by the environmental conditions experienced during adulthood in the years prior to successful reproduction. Birds bred earliest (mean age 4) when environmental conditions were 'good' prior to the year of successful reproduction. Conversely, birds successfully reproduced at older ages (mean age 7) if they experienced adverse conditions prior to the year of successful reproduction. Hatch year conditions and an interaction between those experienced prior to and during the year of successful reproduction explained less (marginally significant) variation in age at first successful reproduction. Environmental conditions did not explain variation in the size of the first successful brood or the proportion of successful breeders. These findings show that conditions during adulthood prior to the year of

Porcine Reproductive and Respiratory Syndrome

USDA-ARS?s Scientific Manuscript database

Porcine reproductive and respiratory syndrome (PRRS) is the number one disease affecting US swine. It is caused by the PRRS virus (PRRSV) and is recognized as reproductive failure of sows and respiratory problems of piglets and growing pigs. This book chapter is part of the Office of International E...

Exposure to ambient air pollution--does it affect semen quality and the level of reproductive hormones?

PubMed

Radwan, Michał; Jurewicz, Joanna; Polańska, Kinga; Sobala, Wojciech; Radwan, Paweł; Bochenek, Michał; Hanke, Wojciech

2016-01-01

Ambient air pollution has been associated with a variety of reproductive disorders. However, a limited amount of research has been conducted to examine the association between air pollution and male reproductive outcomes, specifically semen quality. The present study was designed to address the hypothesis that exposure to fluctuating levels of specific air pollutants adversely affects sperm parameters and the level of reproductive hormones. The study population consisted of 327 men who were attending an infertility clinic in Łodź, Poland for diagnostic purposes and who had normal semen concentration of 15-300 mln/ml. All participants were interviewed and provided a semen sample. Air quality data were obtained from AirBase database. The statistically significant association was observed between abnormalities in sperm morphology and exposure to all examined air pollutants (PM10, PM2.5, SO2, NOX, CO). Exposure to air pollutants (PM10, PM2.5, CO, NOx) was also negatively associated with the level of testosterone. Additional exposure to PM2.5, PM10 increase the percentage of cells with immature chromatin (HDS). The present study provides suggestive evidence of an association between ambient air pollution and sperm quality. Further research is needed to explore this association in more detail. Individual precise exposure assessment would be needed for more detailed risk characterization.

GnRH in the Human Female Reproductive Axis.

PubMed

Limonta, Patrizia; Marelli, Marina Montagnani; Moretti, Roberta; Marzagalli, Monica; Fontana, Fabrizio; Maggi, Roberto

2018-01-01

Gonadotropin-releasing hormone (GnRH) is recognized as the central regulator of the functions of the pituitary-gonadal axis. The increasing knowledge on the mechanisms controlling the development and the function of GnRH-producing neurons is leading to a better diagnostic and therapeutic approach for hypogonadotropic hypogonadisms and for alterations of the puberty onset. During female life span, the function of the GnRH pulse generator may be affected by a number of inputs from other neuronal systems, offering alternative strategies for diagnostic and therapeutic interventions. Moreover, the identification of a GnRH/GnRH receptor system in both human ovary and endometrium has widened the spectrum of action of the peptide outside its hypothalamic functions. The pharmacological use of GnRH itself or its synthetic analogs (agonists and antagonists) provides a valid tool to either stimulate or block gonadotropin secretion and to modulate the female fertility in several reproductive disorders and in assisted reproduction technology. The use of GnRH agonists in young female patients undergoing chemotherapy is also considered a promising therapeutic approach to counteract iatrogenic ovarian failure. © 2018 Elsevier Inc. All rights reserved.

Ejaculate components delay reproductive senescence while elevating female reproductive rate in an insect

PubMed Central

Reinhardt, Klaus; Naylor, Richard A.; Siva-Jothy, Michael T.

2009-01-01

Increased female reproductive rates usually result in accelerated senescence. This correlation provides a link between the evolutionary conflict of the sexes and aging when ejaculate components elevate female reproductive rates at the cost of future reproduction. It is not clear whether this female cost is manifest as shorter lifespan or an earlier onset or a steeper rate of reproductive senescence. It also is unclear whether beneficial ejaculates release females from reproductive trade-offs and, if so, which senescence parameters are affected. We examined these issues in the bedbug, Cimex lectularius, a long-lived insect that shows reduced female lifespan as well as female reproductive senescence at the male-determined mating frequency. We demonstrate experimentally that, independently of the mating frequency, females receiving more ejaculate show increased reproductive rates and enter reproductive senescence later than females receiving less ejaculate. The rate of reproductive senescence did not differ between treatments, and reproductive rates did not predict mortality. The ejaculate effects were consistent in inter- and intra-population crosses, suggesting they have not evolved recently and are not caused by inbreeding. Our results suggest that ejaculate components compensate for the costs of elevated female reproductive rates in bedbugs by delaying the onset of reproductive senescence. Ejaculate components that are beneficial to polyandrous females could have arisen because male traits that protect the ejaculate have positive pleiotropic effects and/or because female counteradaptations to antagonistic male traits exceed the neutralization of those traits. That males influence female reproductive senescence has important consequences for trade-offs between reproduction and longevity and for studies of somatic senescence. PMID:19996174

Current versus future reproduction and longevity: a re-evaluation of predictions and mechanisms

PubMed Central

Zhang, Yufeng

2016-01-01

ABSTRACT Oxidative damage is predicted to be a mediator of trade-offs between current reproduction and future reproduction or survival, but most studies fail to support such predictions. We suggest that two factors underlie the equivocal nature of these findings: (1) investigators typically assume a negative linear relationship between current reproduction and future reproduction or survival, even though this is not consistently shown by empirical studies; and (2) studies often fail to target mechanisms that could link interactions between sequential life-history events. Here, we review common patterns of reproduction, focusing on the relationships between reproductive performance, survival and parity in females. Observations in a range of species show that performance between sequential reproductive events can decline, remain consistent or increase. We describe likely bioenergetic consequences of reproduction that could underlie these changes in fitness, including mechanisms that could be responsible for negative effects being ephemeral, persistent or delayed. Finally, we make recommendations for designing future studies. We encourage investigators to carefully consider additional or alternative measures of bioenergetic function in studies of life-history trade-offs. Such measures include reactive oxygen species production, oxidative repair, mitochondrial biogenesis, cell proliferation, mitochondrial DNA mutation and replication error and, importantly, a measure of the respiratory function to determine whether measured differences in bioenergetic state are associated with a change in the energetic capacity of tissues that could feasibly affect future reproduction or lifespan. More careful consideration of the life-history context and bioenergetic variables will improve our understanding of the mechanisms that underlie the life-history patterns of animals. PMID:27802148

The regulation of reproductive neuroendocrine function by insulin and insulin-like growth factor-1 (IGF-1).

PubMed

Wolfe, Andrew; Divall, Sara; Wu, Sheng

2014-10-01

The mammalian reproductive hormone axis regulates gonadal steroid hormone levels and gonadal function essential for reproduction. The neuroendocrine control of the axis integrates signals from a wide array of inputs. The regulatory pathways important for mediating these inputs have been the subject of numerous studies. One class of proteins that have been shown to mediate metabolic and growth signals to the CNS includes Insulin and IGF-1. These proteins are structurally related and can exert endocrine and growth factor like action via related receptor tyrosine kinases. The role that insulin and IGF-1 play in controlling the hypothalamus and pituitary and their role in regulating puberty and nutritional control of reproduction has been studied extensively. This review summarizes the in vitro and in vivo models that have been used to study these neuroendocrine structures and the influence of these growth factors on neuroendocrine control of reproduction. Copyright © 2014 Elsevier Inc. All rights reserved.

A link between hypothyroidism, obesity and male reproduction.

PubMed

Aiceles, Veronica; da Fonte Ramos, Cristiane

2016-01-01

Hypothyroidism is a condition in which the serum levels of thyroid hormones are below that necessary to carry out physiological functions in the body. Hypothyroidism is related to obesity as an increase in body weight gain is seen in hypothyroid patients. Moreover, an inverse correlation between free thyroxine values and body mass index has been reported. Leptin, a polypeptide hormone produced by adipocytes, was originally thought to be an antiobesity hormone due its anorexic effects on hypothalamic appetite regulation. However, nowadays it is known that leptin conveys information about the nutritional status to the brain being considered a crucial endocrine factor for regulating several physiological processes including reproduction. Since the identification of thyroid hormone and leptin receptors on the testes, these hormones are being recognized as having important roles in male reproductive functions. A clear link exists among thyroid hormones, leptin and reproduction. Both hormones can negatively affect spermatogenesis and consequently may cause male infertility. The World Health Organization (WHO) estimates the overall prevalence of primary infertility ranging from 8 to 15%. The fact that 30% of couples' inability to conceive is related to a male factor and that the longer hypothyroidism persisted, the greater the damage to the testes, strongly suggest that more studies attempting to clarify both hormones actions directly in the testes need to be conducted specially in cases of congenital hypothyroidism. Therefore, the goal of this review is to highlight the relationship of such hormones in the reproductive system.

Survival and reproduction of some nematodes as affected by muck and organic acids.

PubMed

Elmiligy, I A; Norton, D C

1973-01-01

Fulvic, humic, acetic, N-bulyric, formic, lactic, and propionic acids were inhibitory to the survival or reproduction of Aphelenchus avenae, Aphelenchoides goodeyi, Helicotylenchus pseudorobustus, Meloidogyne hapla or Xiphinema americanum. Reproduction of H. pseudorobustus and M. hapla significantly increased with increasing amounts of muck added to sand, and with the initial amount of nematode inoculum. All acids except humic and fulvic were lethal, in vitro, to all nematode species tested. When A. goodeyi was treated with fulvic acid, reproduction was reduced significantly when compared with sodium humate or water treatments. Treatment of H. pseudorobustus with fulvic acid (pH 3.5) resulted in a greater reduction in reproduction in soil than did treatment with humic acid (pH 3.5).

Role of leptin in female reproduction.

PubMed

Pérez-Pérez, Antonio; Sánchez-Jiménez, Flora; Maymó, Julieta; Dueñas, José L; Varone, Cecilia; Sánchez-Margalet, Víctor

2015-01-01

Reproductive function is dependent on energy resources. The role of weight, body composition, fat distribution and the effect of diet have been largely investigated in experimental female animals as well as in women. Any alteration in diet and/or weight may induce abnormalities in timing of sexual maturation and fertility. However, the cellular mechanisms involved in the fine coordination of energy balance and reproduction are largely unknown. The brain and hypothalamic structures receive endocrine and/or metabolic signals providing information on the nutritional status and the degree of fat stores. Adipose tissue acts both as a store of energy and as an active endocrine organ, secreting a large number of biologically important molecules termed adipokines. Adipokines have been shown to be involved in regulation of the reproductive functions. The first adipokine described was leptin. Extensive research over the last 10 years has shown that leptin is not only an adipose tissue-derived messenger of the amount of energy stores to the brain, but also a crucial hormone/cytokine for a number of diverse physiological processes, such as inflammation, angiogenesis, hematopoiesis, immune function, and most importantly, reproduction. Leptin plays an integral role in the normal physiology of the reproductive system with complex interactions at all levels of the hypothalamic-pituitary gonadal (HPG) axis. In addition, leptin is also produced by placenta, where it plays an important autocrine function. Observational studies have demonstrated that states of leptin excess, deficiency, or resistance can be associated with abnormal reproductive function. This review focuses on the leptin action in female reproduction.

Adverse effects of the anabolic steroid, boldenone undecylenate, on reproductive functions of male rabbits

PubMed Central

Oda, Samah S; El-Ashmawy, Ibrahim M

2012-01-01

Summary This study was conducted to evaluate the adverse effects of the anabolic steroid, boldenone undecylenate (BOL) on reproductive functions of male rabbits. Thirty white New Zealand mature male rabbits were divided into three groups (10 rabbits each). Group A rabbits served as a control group. Group B rabbits received 4.4 mg/kg body weight (bwt) BOL 5% oily solution. Group C rabbits received 8.8 mg/kg bwt BOL. Rabbits were injected intramuscularly twice weekly for two months. BOL had no significant effect on the bwt and bwt gain. Testes and epididymis weights were decreased significantly in the BOL-treated groups. BOL caused significant reduction in serum testosterone level, seminal volume, sperm motility, and sperm count. No abnormalities were detected in the sperm morphology of the BOL-treated groups. Histopathological alterations in the testes and epididymis were marked in the group C rabbits. These results indicate that administration of BOL exerts a significant harmful effect on the reproductive functions of male rabbits. PMID:22583130

Factors affecting effective communication about sexual and reproductive health issues between parents and adolescents in zandspruit informal settlement, Johannesburg, South Africa.

PubMed

Motsomi, Kegaugetswe; Makanjee, Chandra; Basera, Tariro; Nyasulu, Peter

2016-01-01

Communication between parents and adolescents regarding sexuality is an important reproductive health topic. Due to complexities associated with adolescent's physiological development, sexuality should be dealt with holistically. This study aimed to investigate factors affecting effective communication between parents and adolescents concerning sexual and reproductive health issues. An exploratory qualitative study using the focus group discussions method was done to explore amongst other things; social, cultural and religious barriers to communication. Thematic content analysis was done. Factors identified included: embarrassment when discussing sexual topics; adolescent misperceptions that guardians want to engage in sexual activities with them; strong belief amongst guardians that reproductive health discussions with adolescents encourages sexual experimentation; belief that adolescents were too young to understand; non-conducive environment for open discussions of sexual and reproductive health matters; cultural and religious beliefs. In view of these findings, there are still barriers in terms of parent-adolescent engagement on issues related to risks associated with sexual behaviours and erroneous reproductive health choices among adolescents. Therefore, there is a need to encourage engagement by creating neutral platforms facilitated by community healthcare providers and/ or social workers. This will help create awareness and bridge the communication and interaction gap by emphasising the importance of effective engagement among adolescents and their parents on matters related to risks associated with sexual behaviours and erroneous reproductive health choices. Post implantation intervention studies are needed to inform on the outcomes of the intervention.

The impact of female reproductive function on outcomes after traumatic brain injury.

PubMed

Ripley, David L; Harrison-Felix, Cindy; Sendroy-Terrill, Melissa; Cusick, Christopher P; Dannels-McClure, Amy; Morey, Clare

2008-06-01

To determine the impact of traumatic brain injury (TBI) on female menstrual and reproductive functioning and to examine the relationships between severity of injury, duration of amenorrhea, and TBI outcomes. Retrospective cohort survey. Telephone interview. Women (N=30; age range, 18-45y), between 1 and 3 years postinjury, who had completed inpatient rehabilitation for TBI. Not applicable. Data collected included menstrual and reproductive functioning pre- and postinjury, demographic, and injury characteristics. Outcome measures included the Glasgow Outcome Scale-Extended (GOS-E), the Mayo-Portland Adaptability Inventory-4 (MPAI-4), and the Medical Outcome Study 12-Item Short-Form Health Survey, Version 2 (SF-12v2). The median duration of amenorrhea was 61 days (range, 20-344d). Many subjects' menstrual function changed after TBI, reporting a significant increase in skipped menses postinjury (P<.001) and a trend toward more painful menses (P=.061). More severe TBI, as measured by the duration of posttraumatic amnesia, was significantly predictive of a longer duration of amenorrhea (P=.004). Subjects with a shorter duration of amenorrhea scored significantly better on the SF-12 physical component subscale (P=.004), the GOS-E (P=.05), and the MPAI-4 participation subscale (P=.05) after controlling for age, injury severity, and time postinjury. The severity of TBI was predictive of duration of amenorrhea and a shorter duration of amenorrhea was predictive of better ratings of global outcome, community participation, and health-related quality of life postinjury.

Gender, sexual health and reproductive health promotion.

PubMed

Moeti, M R

1995-01-01

The underlying factors of poverty, migration, marginalization, lack of information and skills, disempowerment, and poor access to services which affect HIV/STD risk are also closely related to those which affect sexual and reproductive health. Reproductive health problems include unplanned and unwanted pregnancies, unsafe abortions, pregnancy-related illness and death, and STDs including HIV/AIDS. This interrelationship between factors is leading increasingly to the integration of HIV/STD education and prevention within the broader framework of sexual and reproductive health promotion. Such intervention allows the possible reinforcement of the impact of interventions upon important underlying factors and behaviors linked to individual, family, and community vulnerability to HIV/STDs as well as other reproductive health problems. Integration will also optimize the use of increasingly scarce resources and increase the likelihood of responses, interventions, and programs being sustainable. Sexual and reproductive health, placing HIV/STD prevention into context, and focus upon men are discussed.

Oyster reproduction is affected by exposure to polystyrene microplastics.

PubMed

Sussarellu, Rossana; Suquet, Marc; Thomas, Yoann; Lambert, Christophe; Fabioux, Caroline; Pernet, Marie Eve Julie; Le Goïc, Nelly; Quillien, Virgile; Mingant, Christian; Epelboin, Yanouk; Corporeau, Charlotte; Guyomarch, Julien; Robbens, Johan; Paul-Pont, Ika; Soudant, Philippe; Huvet, Arnaud

2016-03-01

Plastics are persistent synthetic polymers that accumulate as waste in the marine environment. Microplastic (MP) particles are derived from the breakdown of larger debris or can enter the environment as microscopic fragments. Because filter-feeder organisms ingest MP while feeding, they are likely to be impacted by MP pollution. To assess the impact of polystyrene microspheres (micro-PS) on the physiology of the Pacific oyster, adult oysters were experimentally exposed to virgin micro-PS (2 and 6 µm in diameter; 0.023 mg·L(-1)) for 2 mo during a reproductive cycle. Effects were investigated on ecophysiological parameters; cellular, transcriptomic, and proteomic responses; fecundity; and offspring development. Oysters preferentially ingested the 6-µm micro-PS over the 2-µm-diameter particles. Consumption of microalgae and absorption efficiency were significantly higher in exposed oysters, suggesting compensatory and physical effects on both digestive parameters. After 2 mo, exposed oysters had significant decreases in oocyte number (-38%), diameter (-5%), and sperm velocity (-23%). The D-larval yield and larval development of offspring derived from exposed parents decreased by 41% and 18%, respectively, compared with control offspring. Dynamic energy budget modeling, supported by transcriptomic profiles, suggested a significant shift of energy allocation from reproduction to structural growth, and elevated maintenance costs in exposed oysters, which is thought to be caused by interference with energy uptake. Molecular signatures of endocrine disruption were also revealed, but no endocrine disruptors were found in the biological samples. This study provides evidence that micro-PS cause feeding modifications and reproductive disruption in oysters, with significant impacts on offspring.

Positive and negative affective processing exhibit dissociable functional hubs during the viewing of affective pictures.

PubMed

Zhang, Wenhai; Li, Hong; Pan, Xiaohong

2015-02-01

Recent resting-state functional magnetic resonance imaging (fMRI) studies using graph theory metrics have revealed that the functional network of the human brain possesses small-world characteristics and comprises several functional hub regions. However, it is unclear how the affective functional network is organized in the brain during the processing of affective information. In this study, the fMRI data were collected from 25 healthy college students as they viewed a total of 81 positive, neutral, and negative pictures. The results indicated that affective functional networks exhibit weaker small-worldness properties with higher local efficiency, implying that local connections increase during viewing affective pictures. Moreover, positive and negative emotional processing exhibit dissociable functional hubs, emerging mainly in task-positive regions. These functional hubs, which are the centers of information processing, have nodal betweenness centrality values that are at least 1.5 times larger than the average betweenness centrality of the network. Positive affect scores correlated with the betweenness values of the right orbital frontal cortex (OFC) and the right putamen in the positive emotional network; negative affect scores correlated with the betweenness values of the left OFC and the left amygdala in the negative emotional network. The local efficiencies in the left superior and inferior parietal lobe correlated with subsequent arousal ratings of positive and negative pictures, respectively. These observations provide important evidence for the organizational principles of the human brain functional connectome during the processing of affective information. © 2014 Wiley Periodicals, Inc.

Application of endocrine disruptor screening program fish short-term reproduction assay: Reproduction and endocrine function in fathead minnow (Pimephales promelas) and killifish (Fundulus heteroclitus) exposed to Bermuda pond sediment.

PubMed

Fort, Douglas J; Mathis, Michael; Fort, Chelsea E; Fort, Hayley M; Bacon, Jamie P

2015-06-01

A modified tier 1 Endocrine Disruptor Screening Program (EDSP) 21-d fish short-term reproduction assay (FSTRA) was used to evaluate the effects of sediment exposure from freshwater and brackish ponds in Bermuda on reproductive fecundity and endocrine function in fathead minnow (Pimephales promelas) and killifish (Fundulus heteroclitus). Reproductively active male and female fish were exposed to control sediment and sediment from 2 freshwater ponds (fathead minnow) and 2 marine ponds (killifish) contaminated with polyaromatic hydrocarbons and metals via flow-through exposure for 21 d. Reproductive fecundity was monitored daily. At termination, the status of the reproductive endocrine system was assessed by the gonadosomatic index, gonadal histology, plasma steroids (estrogen [E2], testosterone [T], and 11-ketotestosterone [11-KT]), steroidogenic enzymes (aromatase and combined 3β/17β -hydroxysteroid dehydrogenase [3β/17β-HSD]), and plasma vitellogenin (VTG). Decreased reproductive fecundity, lower male body weight, and altered endocrinological measures of reproductive status were observed in both species. Higher plasma T levels in female minnows and 11-KT levels in both male and female minnows and female killifish exposed to freshwater and brackish sediments, respectively. Decreased female E2 and VTG levels and gonadal cytochrome P19 (aromatase) activity were also found in sediment exposed females from both species. No effect on female 3β/17β-HSD activity was found in either species. The FSTRA provided a robust model capable of modification to evaluate reproductive effects of sediment exposure in fish. © 2015 SETAC.

Long-Term Exposure to Environmental Concentrations of the Pharmaceutical Ethynylestradiol Causes Reproductive Failure in Fish

PubMed Central

Nash, Jon P.; Kime, David E.; Van der Ven, Leo T. M.; Wester, Piet W.; Brion, François; Maack, Gerd; Stahlschmidt-Allner, Petra; Tyler, Charles R.

2004-01-01

Heightened concern over endocrine-disrupting chemicals is driven by the hypothesis that they could reduce reproductive success and affect wildlife populations, but there is little evidence for this expectation. The pharmaceutical ethynylestradiol (EE2) is a potent endocrine modulator and is present in the aquatic environment at biologically active concentrations. To investigate impacts on reproductive success and mechanisms of disruption, we exposed breeding populations (n = 12) of zebrafish (Danio rerio) over multiple generations to environmentally relevant concentrations of EE2. Life-long exposure to 5 ng/L EE2 in the F1 generation caused a 56% reduction in fecundity and complete population failure with no fertilization. Conversely, the same level of exposure for up to 40 days in mature adults in the parental F0 generation had no impact on reproductive success. Infertility in the F1 generation after life-long exposure to 5 ng/L EE2 was due to disturbed sexual differentiation, with males having no functional testes and either undifferentiated or inter-sex gonads. These F1 males also showed a reduced vitellogenic response when compared with F0 males, indicating an acclimation to EE2 exposure. Depuration studies found only a partial recovery in reproductive capacity after 5 months. Significantly, even though the F1 males lacked functional testes, they showed male-pattern reproductive behavior, inducing the spawning act and competing with healthy males to disrupt fertilization. Endocrine disruption is therefore likely to affect breeding dynamics and reproductive success in group-spawning fish. Our findings raise major concerns about the population-level impacts for wildlife of long-term exposure to low concentrations of estrogenic endocrine disruptors. PMID:15579420

Phthalate exposure and reproductive parameters in young men from the general Swedish population.

PubMed

Axelsson, Jonatan; Rylander, Lars; Rignell-Hydbom, Anna; Jönsson, Bo A G; Lindh, Christian H; Giwercman, Aleksander

2015-12-01

In animals, exposure to certain phthalates negatively affects the male reproductive function. Human results are conflicting and mostly based on subfertile males, in whom the association between exposure and reproductive function may differ from the general population. To study if levels of phthalate metabolites were associated with semen quality and reproductive hormones in general Swedish men. We recruited 314 young men delivering semen, urine and blood samples at the same visit. We analyzed reproductive hormones and several semen parameters including progressive motility and high DNA stainability (HDS)-a marker for sperm immaturity. In urine, we analyzed metabolites of phthalates, including diethylhexyl phthalate (DEHP). We studied associations between urinary levels of the metabolites and seminal as well as serum reproductive parameters, accounting for potential confounders. DEHP metabolite levels, particularly urinary mono-(2-ethyl-5-carboxypentyl) phthalate (MECPP), were negatively associated with progressive sperm motility, which was 11 (95% CI: 5.0-17) percentage points lower in the highest quartile of MECPP than in the lowest. Further, men in the highest quartile of the DEHP metabolite monoethylhexyl phthalate had 27% (95% CI: 5.5%-53%) higher HDS than men in the lowest quartile. DEHP metabolite levels seemed negatively associated with sperm motility and maturation. Copyright © 2015 Elsevier Ltd. All rights reserved.

The vaginal microbiota, host defence and reproductive physiology.

PubMed

Smith, Steven B; Ravel, Jacques

2017-01-15

The interaction between the human host and the vaginal microbiota is highly dynamic. Major changes in the vaginal physiology and microbiota over a woman's lifetime are largely shaped by transitional periods such as puberty, menopause and pregnancy, while daily fluctuations in microbial composition observed through culture-independent studies are more likely to be the results of daily life activities and behaviours. The vaginal microbiota of reproductive-aged women is largely made up of at least five different community state types. Four of these community state types are dominated by lactic-acid producing Lactobacillus spp. while the fifth is commonly composed of anaerobes and strict anaerobes and is sometimes associated with vaginal symptoms. The production of lactic acid has been associated with contributing to the overall health of the vagina due to its direct and indirect effects on pathogens and host defence. Some species associated with non-Lactobacillus vaginal microbiota may trigger immune responses as well as degrade the host mucosa, processes that ultimately increase susceptibility to infections and contribute to negative reproductive outcomes such as infertility and preterm birth. Further studies are needed to better understand the functional underpinnings of how the vaginal microbiota affect host physiology but also how host physiology affects the vaginal microbiota. Understanding this fine-tuned interaction is key to maintaining women's reproductive health. © 2016 The Authors. The Journal of Physiology © 2016 The Physiological Society.

Can safe and long-term exposure to extremely low frequency (50 Hz) magnetic fields affect apoptosis, reproduction, and oxidative stress?

PubMed

Akdag, Mehmet Zulkuf; Dasdag, Suleyman; Uzunlar, Ali Kemal; Ulukaya, Engin; Oral, Arzu Yilmaztepe; Çelik, Necla; Akşen, Feyzan

2013-12-01

To determine whether 50 Hz extremely low frequency-magnetic fields (ELF-MF) affects apoptotic processes, oxidative damage, and reproductive characteristics such as sperm count and morphology in rat testes. Thirty male Sprague-Dawley rats were used in the present study, which were divided into three groups (sham group, n = 10, and two experimental groups, n = 10 for each group). Rats in the experimental group were exposed to 100 and 500 μT ELF-MF (2 h/day, 7 days/week, for 10 months) corresponding to exposure levels that are considered safe for humans. The same experimental procedures were applied to the sham group, but the ELF generator was turned off. Tissues from the testes were immunohistochemically stained for active (cleaved) caspase-3 in order to measure the apoptotic index by a semi-quantitative scoring system. The levels of catalase (CAT), malondialdehyde (MDA), myeloperoxidase (MPO), total antioxidative capacity (TAC), total oxidant status (TOS), and oxidative stress index (OSI) were also measured. Additionally, epididymal sperm count and sperm morphology was evaluated. There were no significant differences in the reproductive and oxidative stress parameters between the sham group and the exposed groups (p > 0.05). While no difference was observed between the final apoptosis score of the sham and the 100 μT ELF-MF group (p > 0.05), the final apoptosis score was higher in the 500 μT ELF-MF exposure group than in the sham group (p < 0.05). Long-term exposure to 100 μT and 500 μT ELF-MF did not affect oxidative or antioxidative processes, lipid peroxidation, or reproductive components such as sperm count and morphology in testes tissue of rats. However, long-term exposure to 500 μT ELF-MF did affect active-caspase-3 activity, which is a well-known apoptotic indicator.

International spinal cord injury male sexual function and female sexual and reproductive function basic data sets-version 2.0.

PubMed

Alexander, Marcalee S; New, Peter W; Biering-Sørensen, Fin; Courtois, Frederique; Popolo, Giulio Del; Elliott, Stacy; Kiekens, Carlotte; Vogel, Lawrence; Previnaire, Jean G

2017-01-01

Data set review and modification. To describe modifications in the International Spinal Cord Injury (SCI) Male Sexual Function Basic Data Set Version 2.0 and the International SCI Female Sexual and Reproductive Function Basic Data Set Version 2.0. International expert work group using on line communication. An international team of experts was compiled to review and revise the International SCI Male Sexual Function and Female Sexual and Reproductive Function Basic Data Sets Version 1.0. The group adapted Version 1.0 based upon review of published research, suggestions from concerned individuals and on line work group consensus. The revised data sets were then posted on the International Spinal Cord Society (ISCoS) and American Spinal Injury Association (ASIA) websites for 2 months for review. Subsequently, the data sets were approved by the ISCoS Scientific and Executive Committees and ASIA board of directors. The data sets were modified to a self-report format. They were reviewed for appropriateness for the pediatric age group and adapted to include a new variable to address the issue of sexual orientation. A clarification of the difference between the data sets and the autonomic standards was also developed. Sexuality is a continuously evolving topic. Modifications were needed to address this topic in a comprehensive fashion. It is recommended that Version 2.0 of these data sets are used for ongoing documentation of sexual status in the medical record and for documentation of sexual concerns during on-going research.

Current versus future reproduction and longevity: a re-evaluation of predictions and mechanisms.

PubMed

Zhang, Yufeng; Hood, Wendy R

2016-10-15

Oxidative damage is predicted to be a mediator of trade-offs between current reproduction and future reproduction or survival, but most studies fail to support such predictions. We suggest that two factors underlie the equivocal nature of these findings: (1) investigators typically assume a negative linear relationship between current reproduction and future reproduction or survival, even though this is not consistently shown by empirical studies; and (2) studies often fail to target mechanisms that could link interactions between sequential life-history events. Here, we review common patterns of reproduction, focusing on the relationships between reproductive performance, survival and parity in females. Observations in a range of species show that performance between sequential reproductive events can decline, remain consistent or increase. We describe likely bioenergetic consequences of reproduction that could underlie these changes in fitness, including mechanisms that could be responsible for negative effects being ephemeral, persistent or delayed. Finally, we make recommendations for designing future studies. We encourage investigators to carefully consider additional or alternative measures of bioenergetic function in studies of life-history trade-offs. Such measures include reactive oxygen species production, oxidative repair, mitochondrial biogenesis, cell proliferation, mitochondrial DNA mutation and replication error and, importantly, a measure of the respiratory function to determine whether measured differences in bioenergetic state are associated with a change in the energetic capacity of tissues that could feasibly affect future reproduction or lifespan. More careful consideration of the life-history context and bioenergetic variables will improve our understanding of the mechanisms that underlie the life-history patterns of animals. © 2016. Published by The Company of Biologists Ltd.

Reproductive Issues in Women with Turner Syndrome.

PubMed

Folsom, Lisal J; Fuqua, John S

2015-12-01

Turner syndrome is one of the most common chromosomal abnormalities affecting female infants. The severity of clinical manifestations varies and it affects multiple organ systems. Women with Turner syndrome have a 3-fold increase in mortality, which becomes even more pronounced in pregnancy. Reproductive options include adoption or surrogacy, assisted reproductive techniques, and in rare cases spontaneous pregnancy. Risks for women with Turner syndrome during pregnancy include aortic disorders, hepatic disease, thyroid disease, type 2 diabetes, and cesarean section delivery. Providers must be familiar with the risks and recommendations in caring for women with Turner syndrome of reproductive age. Copyright © 2015 Elsevier Inc. All rights reserved.

Influence of heavy metals and 4-nonylphenol on reproductive function in fish.

PubMed

Popek, Włodzimierz; Dietrich, Grzegorz; Glogowski, Jan; Demska-Zakeś, Krystyna; Drag-Kozak, Ewa; Sionkowski, Jan; Łuszczek-Trojan, Ewa; Epler, Piotr; Demianowicz, Wiesław; Sarosiek, Beata; Kowalski, Radosław; Jankun, Małgorzata; Zakeś, Zdzisław; Król, Jarosław; Czerniak, Stanisław; Szczepkowski, Mirosław

2006-01-01

Many industrial and agricultural chemicals (including heavy metals and alkylphenols) present in the environment have adverse effects on the reproductive function in fish. Three studies were conducted to assess toxicity of these chemicals towards reproduction of freshwater fish. It was shown that heavy metals added to the diets accumulate in brain tissue of carp, and this accumulation results in inhibition of the secretion of noradrenaline and stimulation of the secretion of dopamine in the hypothalamus. These processes results in a disturbance of hormonal equilibrium of the hypothalamo-pituitary system, which can unfavorably influence the efficiency of artificial spawning in fish. Quality of salmonid and sturgeon sperm was impaired after in vitro exposure to heavy metals. The degree of this toxic effect was species-specific. It was demonstrated that sperm motility parameters appeared to be good indicators of adverse effects of heavy metals fish sperm. The protection role of seminal plasma against toxic effects of heavy metals was suggested for salmonid fish. Oral application of 4-nonylphenol (NP) disrupted reproduction in pikeperch. In juvenile fish a decrease in the percentage of males and an increase of intersex fish was observed in relation to dose of NP and time of exposure to this alkylphenol. Exposure of adult males to the NP led to the reduction in fecundity, milt quality and fertility.

Role of proline and GABA in sexual reproduction of angiosperms

PubMed Central

Biancucci, Marco; Mattioli, Roberto; Forlani, Giuseppe; Funck, Dietmar; Costantino, Paolo; Trovato, Maurizio

2015-01-01

Two glutamate derivatives, proline and γ-aminobutyric acid (GABA), appear to play pivotal roles in different aspects of sexual reproduction in angiosperms, although their precise function in plant reproduction and the molecular basis of their action are not yet fully understood. Proline and GABA have long been regarded as pivotal amino acids in pollen vitality and fertility. Proline may constitute up to 70% of the free amino acid pool in pollen grains and it has been recently shown that Arabidopsis mutants affected in the first and rate-limiting step in proline synthesis produce aberrant and infertile pollen grains, indicating that proline synthesis is required for pollen development and fertility. Concerning GABA, a large body of evidence points to this glutamate derivative as a key determinant of post-pollination fertilization. Intriguingly, proline has also been associated with pollination, another aspect of sexual reproduction, since honeybees were reported to show a strong preference for proline-enriched nectars. In this review, we survey current knowledge on the roles of proline and GABA in plant fertility, and discuss future perspectives potentially capable to improve our understanding on the functions of these amino acids in pollen development, pollination, and pollen tube guidance. PMID:26388884

Oyster reproduction is affected by exposure to polystyrene microplastics

PubMed Central

Sussarellu, Rossana; Suquet, Marc; Thomas, Yoann; Lambert, Christophe; Fabioux, Caroline; Pernet, Marie Eve Julie; Le Goïc, Nelly; Quillien, Virgile; Mingant, Christian; Epelboin, Yanouk; Corporeau, Charlotte; Guyomarch, Julien; Robbens, Johan; Paul-Pont, Ika; Soudant, Philippe; Huvet, Arnaud

2016-01-01

Plastics are persistent synthetic polymers that accumulate as waste in the marine environment. Microplastic (MP) particles are derived from the breakdown of larger debris or can enter the environment as microscopic fragments. Because filter-feeder organisms ingest MP while feeding, they are likely to be impacted by MP pollution. To assess the impact of polystyrene microspheres (micro-PS) on the physiology of the Pacific oyster, adult oysters were experimentally exposed to virgin micro-PS (2 and 6 µm in diameter; 0.023 mg·L−1) for 2 mo during a reproductive cycle. Effects were investigated on ecophysiological parameters; cellular, transcriptomic, and proteomic responses; fecundity; and offspring development. Oysters preferentially ingested the 6-µm micro-PS over the 2-µm-diameter particles. Consumption of microalgae and absorption efficiency were significantly higher in exposed oysters, suggesting compensatory and physical effects on both digestive parameters. After 2 mo, exposed oysters had significant decreases in oocyte number (−38%), diameter (−5%), and sperm velocity (−23%). The D-larval yield and larval development of offspring derived from exposed parents decreased by 41% and 18%, respectively, compared with control offspring. Dynamic energy budget modeling, supported by transcriptomic profiles, suggested a significant shift of energy allocation from reproduction to structural growth, and elevated maintenance costs in exposed oysters, which is thought to be caused by interference with energy uptake. Molecular signatures of endocrine disruption were also revealed, but no endocrine disruptors were found in the biological samples. This study provides evidence that micro-PS cause feeding modifications and reproductive disruption in oysters, with significant impacts on offspring. PMID:26831072

EFFECTS OF 3 WEEK EXPOSURES TO METAM SODIUM ON REPRODUCTIVE FUNCTION IN THE FEMALE RAT

EPA Science Inventory

Metam sodium (MS) is a soil fumigant and Category III pesticide with a relatively low toxicity in mammals. But, there is some indication that it can impair rodent reproductive function. In ovariectomized, estradiol-primed rats, a single ip injection was reported to block the lute...

EFFECTS OF 3 WEEK EXPOSURES ON REPRODUCTIVE FUNCTION IN THE FEMALE RAT TO METAM SODIUM

EPA Science Inventory

Metam sodium (MS) is a soil fumigant and Category III pesticide with a relatively low toxicity in mammals. But, there is some indication that it can impair rodent reproductive function. In ovariectomized, estradiol-primed rats, a single ip injection was reported to block the lute...

Adipokines in human reproduction.

PubMed

Dupont, Joëlle; Pollet-Villard, Xavier; Reverchon, Maxime; Mellouk, Namya; Levy, Rachel

2015-10-01

Adipose tissue communicates with other central and peripheral organs by the synthesis and release of substances called adipokines. The most studied adipokine is leptin but others have been recently identified including resistin, adiponectin, chemerin, omentin and visfatin. These adipokines have a critical role in the development of obesity-related complications and inflammatory conditions. However, they are also involved in other functions in the organism including reproductive functions. Indeed, many groups have demonstrated that adipokine receptors, such as adiponectin and chemerin, but also adipokines themselves (adiponectin, chemerin, resistin, visfatin and omentin) are expressed in human peripheral reproductive tissues and that these adipokines are likely to exert direct effects on these tissues. After a brief description of these new adipokines, an overview of their actions in different human reproductive organs (hypothalamus, pituitary, ovary, testis, uterus and placenta) will be presented. Finally, comments will be made on the eventual alterations of these adipokines in reproductive disorders, with special attention to polycystic ovary syndrome, a disease characterized by dysfunction of gonadal axis and systemic nerve endocrine metabolic network with a prevalence of up to 10% in women of reproductive age.

Impact of Di-2-Ethylhexyl Phthalate Metabolites on Male Reproductive Function: a Systematic Review of Human Evidence.

PubMed

Høyer, Birgit Bjerre; Lenters, Virissa; Giwercman, Aleksander; Jönsson, Bo A G; Toft, Gunnar; Hougaard, Karin S; Bonde, Jens Peter E; Specht, Ina Olmer

2018-03-01

The purpose of this review is to systematically review the literature linking di-2-ethylhexyl phthalate (DEHP) exposure with effects on reproductive health in adult males. Thirty-three papers were included of which 28 were cross-sectional. Twenty-one papers investigated semen samples, 18 investigated reproductive hormones, and three studies investigated time to pregnancy. Studies revealed some but inconsistent indications that higher urinary DEHP metabolite levels are associated with an increase in the proportion of spermatozoa with damaged DNA and to a decrease in sperm concentration and motility. A negative association between DEHP metabolites and testosterone levels was more consistent. DEHP metabolites do not seem to be associated with a delay in time to pregnancy, but data are sparse. The studies on DEHP exposure and reproductive biomarkers in men converge to support the hypothesis that DEHP exposure is related to impaired male reproductive function. Longitudinal studies are needed to establish if the observed associations are causal.

A Single Hot Event That Does Not Affect Survival but Decreases Reproduction in the Diamondback Moth, Plutella xylostella

PubMed Central

Zhang, Wei; Zhao, Fei; Hoffmann, Ary A.; Ma, Chun-Sen

2013-01-01

Extremely hot events (usually involving a few hours at extreme high temperatures in summer) are expected to increase in frequency in temperate regions under global warming. The impact of these events is generally overlooked in insect population prediction, since they are unlikely to cause widespread mortality, however reproduction may be affected by them. In this study, we examined such stress effects in the diamondback moth, Plutella xylostella. We simulated a single extreme hot day (maximum of 40°C lasting for 3, 4 or 5 h) increasingly experienced under field conditions. This event had no detrimental effects on immediate mortality, copulation duration, mating success, longevity or lifetime fecundity, but stressed females produced 21% (after 3 or 4 h) fewer hatched eggs because of a decline in the number and hatching success of eggs laid on the first two days. These negative effects on reproduction were no longer evident in the following days. Male heat exposure led to a similar but smaller effect on fertile egg production, and exposure extended pre-mating period in both sexes. Our results indicate that a single hot day can have detrimental effects on reproduction, particularly through maternal effects on egg hatching, and thereby influence the population dynamics of diamondback moth. PMID:24116081

Digestive Organ in the Female Reproductive Tract Borrows Genes from Multiple Organ Systems to Adopt Critical Functions

PubMed Central

Meslin, Camille; Plakke, Melissa S.; Deutsch, Aaron B.; Small, Brandon S.; Morehouse, Nathan I.; Clark, Nathan L.

2015-01-01

Persistent adaptive challenges are often met with the evolution of novel physiological traits. Although there are specific examples of single genes providing new physiological functions, studies on the origin of complex organ functions are lacking. One such derived set of complex functions is found in the Lepidopteran bursa copulatrix, an organ within the female reproductive tract that digests nutrients from the male ejaculate or spermatophore. Here, we characterized bursa physiology and the evolutionary mechanisms by which it was equipped with digestive and absorptive functionality. By studying the transcriptome of the bursa and eight other tissues, we revealed a suite of highly expressed and secreted gene products providing the bursa with a combination of stomach-like traits for mechanical and enzymatic digestion of the male spermatophore. By subsequently placing these bursa genes in an evolutionary framework, we found that the vast majority of their novel digestive functions were co-opted by borrowing genes that continue to be expressed in nonreproductive tissues. However, a number of bursa-specific genes have also arisen, some of which represent unique gene families restricted to Lepidoptera and may provide novel bursa-specific functions. This pattern of promiscuous gene borrowing and relatively infrequent evolution of tissue-specific duplicates stands in contrast to studies of the evolution of novelty via single gene co-option. Our results suggest that the evolution of complex organ-level phenotypes may often be enabled (and subsequently constrained) by changes in tissue specificity that allow expression of existing genes in novel contexts, such as reproduction. The extent to which the selective pressures encountered in these novel roles require resolution via duplication and sub/neofunctionalization is likely to be determined by the need for specialized reproductive functionality. Thus, complex physiological phenotypes such as that found in the bursa offer

Adverse effects of the anabolic steroid, boldenone undecylenate, on reproductive functions of male rabbits.

PubMed

Oda, Samah S; El-Ashmawy, Ibrahim M

2012-06-01

This study was conducted to evaluate the adverse effects of the anabolic steroid, boldenone undecylenate (BOL) on reproductive functions of male rabbits. Thirty white New Zealand mature male rabbits were divided into three groups (10 rabbits each). Group A rabbits served as a control group. Group B rabbits received 4.4 mg/kg body weight (bwt) BOL 5% oily solution. Group C rabbits received 8.8 mg/kg bwt BOL. Rabbits were injected intramuscularly twice weekly for two months. BOL had no significant effect on the bwt and bwt gain. Testes and epididymis weights were decreased significantly in the BOL-treated groups. BOL caused significant reduction in serum testosterone level, seminal volume, sperm motility, and sperm count. No abnormalities were detected in the sperm morphology of the BOL-treated groups. Histopathological alterations in the testes and epididymis were marked in the group C rabbits. These results indicate that administration of BOL exerts a significant harmful effect on the reproductive functions of male rabbits. © 2012 The Authors. International Journal of Experimental Pathology © 2012 International Journal of Experimental Pathology.

Reproduction in the space environment: Part I. Animal reproductive studies

NASA Technical Reports Server (NTRS)

Santy, P. A.; Jennings, R. T.; Craigie, D.

1990-01-01

Mankind's exploration and colonization of the frontier of space will ultimately depend on men's and women's ability to live, work, and reproduce in the space environment. This paper reviews animal studies, from microorganisms to mammals, done in space or under space-simulated conditions, which identify some of the key areas which might interfere with human reproductive physiology and/or embryonic development. Those space environmental factors which impacted almost all species included: microgravity, artificial gravity, radiation, and closed life support systems. These factors may act independently and in combination to produce their effects. To date, there have been no studies which have looked at the entire process of reproduction in any animal species. This type of investigation will be critical in understanding and preventing the problems which will affect human reproduction. Part II will discuss these problems directly as they relate to human physiology.

Male rank affects reproductive success and offspring performance in bank voles.

PubMed

Kruczek, Małgorzata; Zatorska, Magdalena

2008-07-05

Laboratory studies reveal that in several rodent species the females prefer dominant males as mating partners. Here we investigate the correlation between males' social rank and their reproductive success. Similar numbers of females mating with relatively more dominant or relatively more subordinate males produced a litter, and parturition took place 19-21 days after mating. Relatively more dominant males tended to sire more pups than did relatively more subordinates, but the mean number of offspring per litter did not differ significantly between the two groups. Significantly more pups fathered by relatively more dominant males survived to weaning than those sired by relatively more subordinate fathers. Dominance had a long-term effect on the reproductive activity of the offspring: their rate of sexual maturation was increased. In pups sired by a relatively more dominant father, the uteruses of females, and the testes and accessory sex glands of males, were significantly heavier than those of offspring born to relatively more subordinate males. Our results suggest that social rank is an important determinant of the reproductive success of bank vole males.

Early-life nutritional effects on the female reproductive system.

PubMed

Chan, K A; Tsoulis, M W; Sloboda, D M

2015-02-01

There is now considerable epidemiological and experimental evidence indicating that early-life environmental conditions, including nutrition, affect subsequent development in later life. These conditions induce highly integrated responses in endocrine-related homeostasis, resulting in persistent changes in the developmental trajectory producing an altered adult phenotype. Early-life events trigger processes that prepare the individual for particular circumstances that are anticipated in the postnatal environment. However, where the intrauterine and postnatal environments differ markedly, such modifications to the developmental trajectory may prove maladaptive in later life. Reproductive maturation and function are similarly influenced by early-life events. This should not be surprising, because the primordial follicle pool is established early in life and is thus vulnerable to early-life events. Results of clinical and experimental studies have indicated that early-life adversity is associated with a decline in ovarian follicular reserve, changes in ovulation rates, and altered age at onset of puberty. However, the underlying mechanisms regulating the relationship between the early-life developmental environment and postnatal reproductive development and function are unclear. This review examines the evidence linking early-life nutrition and effects on the female reproductive system, bringing together clinical observations in humans and experimental data from targeted animal models. © 2015 Society for Endocrinology.

Ovarian function's role during cancer cachexia progression in the female mouse.

PubMed

Hetzler, Kimbell L; Hardee, Justin P; LaVoie, Holly A; Murphy, E Angela; Carson, James A

2017-05-01

Cachexia is a debilitating condition that occurs with chronic disease, including cancer; our research has shown that some regulation of cancer cachexia progression is affected by sex differences. The Apc Min/+ mouse is genetically predisposed to develop intestinal tumors; IL-6 signaling and hypogonadism are associated with cachexia severity in the male. This relationship in the female warrants further investigation, as we have shown that the ability of IL-6 to induce cachexia differs between the sexes. Since ovarian reproductive function relies on a complex system of endocrine signaling to affect whole body homeostasis, we examined the relationship between ovarian reproductive function and progression of cancer cachexia in the female Apc Min/+ mouse. Our study of ovarian reproductive function in female Apc Min/+ mice showed disease-related cessation of estrous cycling (acyclicity) in 38% of mice. Acyclicity, including morphological and functional losses and enhanced muscle inflammatory gene expression, was associated with severe cachexia. Interestingly, ovariectomy rescued body weight and muscle mass and function but increased muscle sensitivity to systemic IL-6 overexpression. In conclusion, our results provide evidence for a relationship between ovarian reproductive function and cachexia progression in female Apc Min/+ mice. Copyright © 2017 the American Physiological Society.

Honey Bee (Apis mellifera) Queen Reproductive Potential Affects Queen Mandibular Gland Pheromone Composition and Worker Retinue Response.

PubMed

Rangel, Juliana; Böröczky, Katalin; Schal, Coby; Tarpy, David R

2016-01-01

Reproductive division of labor is one of the defining traits of honey bees (Apis mellifera), with non-reproductive tasks being performed by workers while a single queen normally monopolizes reproduction. The decentralized organization of a honey bee colony is maintained in large part by a bouquet of queen-produced pheromones, the distribution of which is facilitated by contact among workers throughout the hive. Previous studies have shown that the developmental fate of honey bee queens is highly plastic, with queens raised from younger worker larvae exhibiting higher measures of reproductive potential compared to queens raised from older worker larvae. We investigated differences in the chemical composition of the mandibular glands and attractiveness to workers of "high-quality" queens (i.e., raised from first instar worker larvae; more queen-like) and "low-quality" queens (i.e., raised from third instar worker larvae; more worker-like). We characterized the chemical profiles of the mandibular glands of high-quality queens and low-quality queens using GC-MS and used the worker retinue response as a measure of the attractiveness to workers of high-quality queens vs. low-quality queens. We found that queen quality affected the chemical profiles of mandibular gland contents differently across years, showing significant differences in the production of the queen mandibular pheromone ("QMP") components HVA and 9-HDA in 2010, but no significant differences of any glandular compound in 2012. We also found that workers were significantly more attracted to high-quality queens than to low-quality queens in 2012, possibly because of increased attractiveness of their mandibular gland chemical profiles. Our results indicate that the age at which honey bee larvae enter the "queen-specific" developmental pathway influences the chemical composition of queen mandibular glands and worker behavior. However, these changes are not consistent across years, suggesting that other external

Excessive dietary calcium in the disruption of structural and functional status of adult male reproductive system in rat with possible mechanism.

PubMed

K Chandra, Amar; Sengupta, Pallav; Goswami, Haimanti; Sarkar, Mahitosh

2012-05-01

Calcium is essential for functioning of different systems including male reproduction. However, it has also been reported as chemo-castrative agent. The study has been undertaken to elucidate the effect of excessive dietary calcium on male reproductive system in animals with possible action. Adult male healthy rats fed CaCl(2) at different doses (0.5, 1.0 and 1.5 g%) in diet for 13 and 26 days to investigate reproductive parameters as well as the markers of oxidative stress. Significant alteration was found (P < 0.05) in testicular and accessory sex organs weight, epididymal sperm count, testicular steroidogenic enzyme (Δ(5) 3β-HSD and 17β-HSD) activities, serum testosterone, LH, FSH, LPO, activities of antioxidant enzymes, testicular histoarchitecture along with adrenal Δ(5) 3β-HSD activity with corticosterone level in dose- and time-dependent manner. Overall observations suggest that excessive dietary calcium enhances the generation of free-radicals resulting in structural and functional disruption of male reproduction.

Insulin: its Role in the Central Control of Reproduction

PubMed Central

Sliwowska, Joanna H.; Fergani, Chrysanthi; Gawałek, Monika; Skowronska, Bogda; Fichna, Piotr; Lehman, Michael N.

2014-01-01

Insulin has long been recognized as a key regulator of energy homeostasis via its actions at the level of the brain, but in addition, plays a role in regulating neural control of reproduction. In this review, we consider and compare evidence from animal models demonstrating a role for insulin for physiological control of reproduction by effects on GnRH/LH secretion. We also review the role that insulin plays in prenatal programming of adult reproduction, and consider specific candidate neurons in the adult hypothalamus by which insulin may act to regulate reproductive function. Finally, we review clinical evidence of the role that insulin may play in adult human fertility and reproductive disorders. Overall, while insulin appears to have a significant impact on reproductive neuroendocrine function, there are many unanswered questions regarding its precise sites and mechanisms of action, and their impact on developing and adult reproductive neuroendocrine function. PMID:24874777

RELATIONSHIP BETWEEN ETHINYLESTRADIOL-MEDIATED CHANGES IN ENDOCRINE FUNCTION AND REPRODUCTION IMPAIRMENT IN JAPANESE MEDAKA (ORYZIAS LATIPES)

EPA Science Inventory

Many biochemical endpoints currently are used to describe endocrine function in fish; however, the sensitivity of these parameters as biomarkers of impaired reproduction or sexual development is not well understood. In the present study, adult Japanese medaka (Oryzias latipes) we...

[Astaxanthin in male reproduction: Advances in studies].

PubMed

Liu, Wei; Kang, Xiao-Fang; Shang, Xue-Jun

2016-10-01

Astaxanthin (AST) is a carotenoid with a strong antioxidant activity and has many biological functions, such as anti-inflammation, immune regulation, anti-tumor, anti-oxidation, anti-aging, and anti-apoptosis. Recent studies show that AST can effectively regulate the dynamic balance between oxidation and antioxidants in the male reproductive system, protect sperm mitochondrial function, ameliorate testicular heat stress and reproductive poison damage, promote the occurrence of sperm capacitation and acrosome reaction, regulate reproductive endocrine hormone balance, and act favorably on primary infertility or metabolic syndrome-related infertility. It also helps the treatment of late-onset hypogonadism and prostate health care. This review updates the studies of AST in male reproductive health and provides some new ideas for the prevention and treatment of male reproductive problems.

Risk factors that affect reproductive target achievement in fertile dairy cows.

PubMed

Aungier, S P M; Roche, J F; Diskin, M G; Crowe, M A

2014-01-01

The aims of the present study were to investigate (1) the risk factors that influence the achievement of reproductive targets postpartum (pp) and (2) the key factors that influence pregnancy rate following first artificial insemination (AI) in dairy cows. Ninety-eight Holstein-Friesian pp cows were blood sampled from wk 1 to 4 pp for hematology and biochemistry. Reproductive tract health was assessed weekly by ultrasonography and vaginal mucus scoring. Body condition score (BCS), lameness score, and milk yield were assessed every 2 wk. Milk samples for progesterone assay were collected twice weekly and on d 4, 5, and 7 after AI. Risk factors associated with achieving reproductive targets depended on (1) increased metabolic activity of the liver (increased glutamate dehydrogenase at calving and increased γ-glutamyl transpeptidase in wk 4), (2) a competent immune system (increased neutrophils in wk 1; decreased α1-acid glycoprotein in wk 1, 2, and 3), (3) an endocrine system that was capable of responding by producing sufficient triiodothyronine in wk 2 and increased insulin-like growth factor I in wk 3 and 4, (4) a lower negative energy balance status (decreased nonesterified fatty acid concentration in wk 1; decreased β-hydroxybutyrate concentration in wk 2; BCS loss between calving and d 28 pp <0.5), (5) good reproductive tract health [normal uterine scan at d 45 pp; clear vaginal mucus discharge at first ovulation and at d 45 pp; resumed ovarian cyclicity by the end of the voluntary waiting period (≥ d 35 pp)], and (6) adequate diet (to ensure increased glutathione peroxidase in wk 2 and 3 and increased magnesium in wk 4). Risk factors that increased the odds of a successful first AI were previous ovulation(s) (odds ratio=3.17 per ovulation), BCS >2.5 at AI (odds ratio=3.01), and clear vaginal mucus (score=0) compared with purulent mucus (score >0) 4 d after first AI (odds ratio=2.99). In conclusion, this study identified key risk factors in the early pp

Workplace reproductive problems.

PubMed

Frazier, L M

2000-12-01

Occupational exposures can harm reproductive processes in men or women. Exposures may affect fertility, pregnancy outcomes or the child's health after delivery. The goal of patient management is to provide counseling at an appropriate level. Over-restricting the patient should be avoided while hazardous exposures should be identified and reduced. The occupational history can be used to estimate the magnitude of each exposure. If the exposure is a known reproductive hazard and the exposure level appears significant, there are several options for making the job safer. Modifications in work practices can be accomplished by advising the patient about changing work practices, writing formal work restrictions and talking with the employer. Temporary job transfers may be available. In some cases, a medical leave is needed. The primary care provider can play a key role in assisting patients to reduce reproductive risks.

Influence of body condition on reproductive output in the guinea pig.

PubMed

Michel, Catherine Louise; Bonnet, Xavier

2012-01-01

Reproduction is expensive. Substantial body reserves (i.e. high body condition) are usually required for females to undertake offspring production. In many vertebrates, maternal body condition positively influences reproductive output, and emaciated individuals skip reproduction. However, the impact of extremely high body condition, more specifically obesity, on animal reproductive performance remains poorly understood and research has generated contradictory results. For instance, obesity negatively affects fertility in women, but does not influence reproductive capacity or reproductive output in laboratory rodents. We examined the influence of high body condition on reproductive status and reproductive output in the guinea pig. In captivity, when fed ad libitum, guinea pigs store large amounts of fat tissues and exhibit a tendency for obesity. Our results show that obesity negatively affected reproduction in this species: both the proportion of fertile females and litter size were lower in the fattest females. Therefore, guinea pigs may represent suitable organisms to better understand the negative effect of obesity on reproduction. Copyright © 2011 Wiley Periodicals, Inc., A Wiley Company.

Environmental hexachlorobenzene exposure and human male reproductive function.

PubMed

Specht, Ina Olmer; Bonde, Jens Peter Ellekilde; Toft, Gunnar; Giwercman, Aleksander; Spanò, Marcello; Bizzaro, Davide; Manicardi, Gian Carlo; Jönsson, Bo A G; Robbins, Wendie A

2015-12-01

Hexachlorobenzene (HCB) is a persistent environmental fungicide that may disrupt androgen regulation. The aim of this study was to investigate associations between HCB levels and biomarkers of male reproductive function. 589 Spouses of pregnant women from Greenland, Poland and Ukraine were enrolled between 2002 and 2004. The men provided semen and blood samples and were interviewed. HCB was measured in serum by gas chromatography. The mean serum concentrations of HCB were higher in Ukraine (182.3ng/g lipid) and Greenland (79.0ng/g lipid) compared to Poland (14.2ng/g lipid). Sex hormone binding globulin (SHBG) and free androgen index (FAI) were associated with HCB in men from Ukraine and Poland. This study spanning large differences in environmental HCB exposure levels shows a positive association for SHBG and negative association for FAI with high serum levels of HCB in fertile men, but without major consequences for semen quality and the Inuit study population. Copyright © 2015 Elsevier Inc. All rights reserved.

EGFR ligands exert diverging effects on male reproductive organs.

PubMed

Schneider, Marlon R; Gratao, Ana A; Dahlhoff, Maik; Boersma, Auke; Hrabé de Angelis, Martin; Hoang-Vu, Cuong; Wolf, Eckhard; Klonisch, Thomas

2010-02-01

While the EGFR and most of its ligands are expressed in the male reproductive tract, their functions in male reproduction are poorly understood. Interestingly, male transgenic mice overexpressing EGF are sterile, and transgenic mice overexpressing TGFA, another EGFR ligand, show an enlarged coagulation gland (anterior prostate) due to severe hyperplasia with focal dysplasia. We studied the male reproductive tract of transgenic mice overexpressing betacellulin (BTC-tg) under the control of a promoter conferring widespread transgene expression. Despite strong overexpression of BTC in different parts of the male reproductive tract, the gross appearance and histology of the reproductive organs of BTC-tg males were normal and the same were true for sperm parameters and the in vitro fertilization rate. Collectively, our findings demonstrate that excess of BTC exerts no deleterious effects on the structure or function of the male reproductive tract in mice and indicates unique, non-overlapping functions of specific EGFR ligands in male reproduction. Copyright 2009 Elsevier Inc. All rights reserved.

Insulin: its role in the central control of reproduction.

PubMed

Sliwowska, Joanna H; Fergani, Chrysanthi; Gawałek, Monika; Skowronska, Bogda; Fichna, Piotr; Lehman, Michael N

2014-06-22

Insulin has long been recognized as a key regulator of energy homeostasis via its actions at the level of the brain, but in addition, plays a role in regulating neural control of reproduction. In this review, we consider and compare evidence from animal models demonstrating a role for insulin for physiological control of reproduction by effects on GnRH/LH secretion. We also review the role that insulin plays in prenatal programming of adult reproduction, and consider specific candidate neurons in the adult hypothalamus by which insulin may act to regulate reproductive function. Finally, we review clinical evidence of the role that insulin may play in adult human fertility and reproductive disorders. Overall, while insulin appears to have a significant impact on reproductive neuroendocrine function, there are many unanswered questions regarding its precise sites and mechanisms of action, and their impact on developing and adult reproductive neuroendocrine function. Copyright © 2014 Elsevier Inc. All rights reserved.

Genetic selection for temperament affects behaviour and the secretion of adrenal and reproductive hormones in sheep subjected to stress.

PubMed

Hawken, P A R; Luckins, N; Tilbrook, A; Fiol, C; Martin, G B; Blache, D

2013-01-01

We investigated the effect of genetic selection for temperament on the way that stressors affect the behaviour and the adrenal and reproductive axes of sheep. We tested three hypotheses: (i) isolation would increase cortisol secretion and decrease luteinising hormone (LH) secretion more in nervous sheep than in calm sheep; (ii) isolation combined with simulated human presence would increase cortisol secretion and decrease LH secretion more in nervous sheep than in calm sheep and (iii) isolation combined with stressors that were not specific to the selection process (i.e. non-selection stressors) would increase cortisol secretion and decrease LH secretion equally in calm and nervous sheep. Isolation alone increased cortisol secretion and decreased LH secretion in nervous sheep but not in calm sheep. Compared to calm sheep, nervous sheep were more agitated during the first 2 h of isolation but not during the second 2 h of isolation. Exposure to non-selection stressors increased cortisol secretion, decreased LH pulse amplitude and the mean plasma concentrations of LH in both calm and nervous sheep. We conclude that genetic selection for temperament affects the behavioural expression of the stress response and the secretion of adrenal and reproductive hormones during isolation, but has less impact on their reactivity to non-selection stressors.

Effects of global warming on fish reproductive endocrine axis, with special emphasis in pejerrey Odontesthes bonariensis.

PubMed

Miranda, Leandro Andrés; Chalde, Tomás; Elisio, Mariano; Strüssmann, Carlos Augusto

2013-10-01

The ongoing of global warming trend has led to an increase in temperature of several water bodies. Reproduction in fish, compared with other physiological processes, only occurs in a bounded temperature range; therefore, small changes in water temperature could significantly affect this process. This review provides evidence that fish reproduction may be directly affected by further global warming and that abnormal high water temperature impairs the expression of important genes throughout the brain-pituitary-gonad axis. In all fishes studied, gonads seem to be the organ more readily damaged by heat treatments through the inhibition of the gene expression and subsequent synthesis of different gonadal steroidogenic enzymes. In view of the feedback role of sex steroids upon the synthesis and release of GnRH and GtHs in fish, it is possible that the inhibition observed at brain and pituitary levels in treated fish is consequence of the sharp decrease in plasma steroids levels. Results of in vitro studies on the inhibition of pejerrey gonad aromatase expression by high temperature corroborate that ovary functions are directly disrupted by high temperature independently of the brain-pituitary axis. For the reproductive responses obtained in laboratory fish studies, it is plausible to predict changes in the timing and magnitude of reproductive activity or even the total failure of spawning season may occur in warm years, reducing annual reproductive output and affecting future populations. Copyright © 2013 Elsevier Inc. All rights reserved.

Chronic Exposure to Bisphenol A Affects Uterine Function During Early Pregnancy in Mice

PubMed Central

Davila, Juanmahel; Kannan, Athilakshmi; Flaws, Jodi A.; Bagchi, Milan K.

2016-01-01

Environmental and occupational exposure to bisphenol A (BPA), a chemical widely used in polycarbonate plastics and epoxy resins, has received much attention in female reproductive health due to its widespread toxic effects. Although BPA has been linked to infertility and recurrent miscarriage in women, the impact of its exposure on uterine function during early pregnancy remains unclear. In this study, we addressed the effect of prolonged exposure to an environmental relevant dose of BPA on embryo implantation and establishment of pregnancy. Our studies revealed that treatment of mice with BPA led to improper endometrial epithelial and stromal functions thus affecting embryo implantation and establishment of pregnancy. Upon further analyses, we found that the expression of progesterone receptor (PGR) and its downstream target gene, HAND2 (heart and neural crest derivatives expressed 2), was markedly suppressed in BPA-exposed uterine tissues. Previous studies have shown that HAND2 controls embryo implantation by repressing fibroblast growth factor and the MAPK signaling pathways and inhibiting epithelial proliferation. Interestingly, we observed that down-regulation of PGR and HAND2 expression in uterine stroma upon BPA exposure was associated with enhanced activation of fibroblast growth factor and MAPK signaling in the epithelium, thus contributing to aberrant proliferation and lack of uterine receptivity. Further, the differentiation of endometrial stromal cells to decidual cells, an event critical for the establishment and maintenance of pregnancy, was severely compromised in response to BPA. In summary, our studies revealed that chronic exposure to BPA impairs PGR-HAND2 pathway and adversely affects implantation and the establishment of pregnancy. PMID:27022677

Transgenic mouse models in the study of reproduction: insights into GATA protein function.

PubMed

Tevosian, Sergei G

2014-07-01

For the past 2 decades, transgenic technology in mice has allowed for an unprecedented insight into the transcriptional control of reproductive development and function. The key factor among the mouse genetic tools that made this rapid advance possible is a conditional transgenic approach, a particularly versatile method of creating gene deletions and substitutions in the mouse genome. A centerpiece of this strategy is an enzyme, Cre recombinase, which is expressed from defined DNA regulatory elements that are active in the tissue of choice. The regulatory DNA element (either genetically engineered or natural) assures Cre expression only in predetermined cell types, leading to the guided deletion of genetically modified (flanked by loxP or 'floxed' by loxP) gene loci. This review summarizes and compares the studies in which genes encoding GATA family transcription factors were targeted either globally or by Cre recombinases active in the somatic cells of ovaries and testes. The conditional gene loss experiments require detailed knowledge of the spatial and temporal expression of Cre activity, and the challenges in interpreting the outcomes are highlighted. These studies also expose the complexity of GATA-dependent regulation of gonadal gene expression and suggest that gene function is highly context dependent. © 2014 Society for Reproduction and Fertility.

Effects of immunization against LHRH and treatment with trenbolone acetate on reproductive function of beef bulls and steers

USDA-ARS?s Scientific Manuscript database

The objectives of this study were (1) to evaluate the ability of trenbolone acetate (TBA) administered in tandem with LHRH immunization to suppress reproductive function in beef bulls and (2) to examine the effects of LHRH and androgen (TBA) signaling on pituitary function. In order to address thes...

The role of adiponectin in reproduction: from polycystic ovary syndrome to assisted reproduction

PubMed Central

Michalakis, Konstantinos G.; Segars, James H.

2011-01-01

Objective To summarize the effects of the adipokine adiponectin on the reproductive endocrine system, from the hypothalamic-pituitary axis to the gonads and target tissues of the reproductive system. Design A Medline computer search was performed to identify relevant articles. Setting Research institution. Intervention(s) None. Result(s) Adiponectin is a hormone secreted by adipose tissue that acts to reduce insulin resistance and atherogenic damage, but it also exerts actions in other tissues. Adiponectin mediates its actions in the periphery mainly via two receptors, AdipoR1 and AdipoR2. Adiponectin receptors are present in many reproductive tissues, including the central nervous system, ovaries, oviduct, endometrium, and testes. Adiponectin influences gonadotropin release, normal pregnancy, and assisted reproduction outcomes. Conclusion(s) Adiponectin, a beneficial adipokine, represents a major link between obesity and reproduction. Higher levels of adiponectin are associated with improved menstrual function and better outcomes in assisted reproductive cycles. PMID:20561616

Effect of Dietary Vitamin A on Reproductive Performance and Immune Response of Broiler Breeders

PubMed Central

Guo, Yuming; Wang, Yongwei; Guo, Shuangshuang

2014-01-01

The effects of dietary vitamin A supplementation on reproductive performance, liver function, fat-soluble vitamin retention, and immune response were studied in laying broiler breeders. In the first phase of the experiment, 1,120 Ross-308 broiler breeder hens were fed a diet of corn and soybean meal supplemented with 5,000 to 35,000 IU/kg vitamin A (retinyl acetate) for 20 weeks. In the second phase, 384 Ross-308 broiler breeder hens were fed the same diet supplemented with 5,000 to 135,000 IU/kg vitamin A (retinyl acetate) for 24 weeks. The hens' reproductive performance, the concentrations of vitamins A and E in liver and egg yolk, liver function, mRNA expression of vitamin D receptor in duodenal mucosa, antibody titers against Newcastle disease virus vaccine, and T-cell proliferation responses were evaluated. Supplementation of vitamin A at levels up to and including 35,000 IU/kg did not affect reproductive performance and quadratically affected antibody titer to Newcastle disease virus vaccine (p<0.05). Dietary addition of vitamin A linearly increased vitamin A concentration in liver and yolk and linearly decreased α-, γ-, and total tocopherol concentration in yolk (p<0.01) and α-tocopherol in liver (p<0.05). Supplementation of vitamin A at doses of 45,000 IU/kg and above significantly decreased egg weight, yolk color, eggshell thickness and strength, and reproductive performance. Dietary vitamin A significantly increased mRNA expression of vitamin D receptor in duodenal mucosa (p<0.05), increased aspartate amino transferase activity, and decreased total bilirubin concentration in serum. Supplementation of vitamin A at 135,000 IU/kg decreased the proliferation of peripheral blood lymphocytes (p<0.05). Therefore, the maximum tolerable dose of vitamin A for broiler breeders appears to be 35,000 IU/kg, as excessive supplementation has been shown to impair liver function, reproductive performance, and immune response. PMID:25148198

High contaminant loads in Lake Apopka's riparian wetland disrupt gene networks involved in reproduction and immune function in largemouth bass.

PubMed

Martyniuk, Christopher J; Doperalski, Nicholas J; Prucha, Melinda S; Zhang, Ji-Liang; Kroll, Kevin J; Conrow, Roxanne; Barber, David S; Denslow, Nancy D

2016-09-01

Lake Apopka (FL, USA) has elevated levels of some organochlorine pesticides in its sediments and a portion of its watershed has been designated a US Environmental Protection Agency Superfund site. This study assessed reproductive endpoints in Florida largemouth bass (LMB) (Micropterus salmoides floridanus) after placement into experimental ponds adjacent to Lake Apopka. LMB collected from a clean reference site (DeLeon Springs) were stocked at two periods of time into ponds constructed in former farm fields on the north shore of the lake. LMB were stocked during early and late oogenesis to determine if there were different effects of contamination on LMB that may be attributed to their reproductive stage. LMB inhabiting the ponds for ~4months had anywhere from 2 to 800 times higher contaminant load for a number of organochlorine pesticides (e.g. p, p'-DDE, methoxychlor) compared to control animals. Gonadosomatic index and plasma vitellogenin were not different between reproductively-stage matched LMB collected at reference sites compared to those inhabiting the ponds. However, plasma 17β-estradiol was lower in LMB inhabiting the Apopka ponds compared to ovary stage-matched LMB from the St. Johns River, a site used as a reference site. Sub-network enrichment analysis revealed that genes related to reproduction (granulosa function, oocyte development), endocrine function (steroid metabolism, hormone biosynthesis), and immune function (T cell suppression, leukocyte accumulation) were differentially expressed in the ovaries of LMB placed into the ponds. These data suggest that (1) LMB inhabiting the Apopka ponds showed disrupted reproduction and immune responses and that (2) gene expression profiles provided site-specific information by discriminating LMB from different macro-habitats. Copyright © 2016 Elsevier Inc. All rights reserved.

Subtle reproductive impairment through nitric oxide-mediated mechanisms in sea urchins from an area affected by harmful algal blooms

PubMed Central

Migliaccio, Oriana; Castellano, Immacolata; Di Cioccio, Davide; Tedeschi, Gabriella; Negri, Armando; Cirino, Paola; Romano, Giovanna; Zingone, Adriana; Palumbo, Anna

2016-01-01

The health of the sea urchin Paracentrotus lividus, a key species in the Mediterranean Sea, is menaced by several pressures in coastal environments. Here, we aimed at assessing the reproductive ability of apparently healthy P. lividus population in a marine protected area affected by toxic blooms of Ostreospsis cf. ovata. Wide-ranging analyses were performed in animals collected prior to and during the bloom, as well as at several times thereafter, during the reproductive season. Adults showed a low fertilization rate, along with high nitric oxide (NO) levels in the gonads and the nitration of the major yolk protein toposome, which is an important player in sea urchin development. Serious developmental anomalies were observed in the progeny, which persist several months after the bloom. NO levels were high in the different developmental stages, which also showed variations in the transcription of several genes that were found to be directly or indirectly modulated by NO. These results highlight subtle but important reproductive flaws transmitted from the female gonads to the offspring with the NO involvement. Despite a recovery along time after the bloom, insidious damages can be envisaged in the local sea urchin population, with possible reverberation on the whole benthic system. PMID:27192939

Subtle reproductive impairment through nitric oxide-mediated mechanisms in sea urchins from an area affected by harmful algal blooms

NASA Astrophysics Data System (ADS)

Migliaccio, Oriana; Castellano, Immacolata; di Cioccio, Davide; Tedeschi, Gabriella; Negri, Armando; Cirino, Paola; Romano, Giovanna; Zingone, Adriana; Palumbo, Anna

2016-05-01

The health of the sea urchin Paracentrotus lividus, a key species in the Mediterranean Sea, is menaced by several pressures in coastal environments. Here, we aimed at assessing the reproductive ability of apparently healthy P. lividus population in a marine protected area affected by toxic blooms of Ostreospsis cf. ovata. Wide-ranging analyses were performed in animals collected prior to and during the bloom, as well as at several times thereafter, during the reproductive season. Adults showed a low fertilization rate, along with high nitric oxide (NO) levels in the gonads and the nitration of the major yolk protein toposome, which is an important player in sea urchin development. Serious developmental anomalies were observed in the progeny, which persist several months after the bloom. NO levels were high in the different developmental stages, which also showed variations in the transcription of several genes that were found to be directly or indirectly modulated by NO. These results highlight subtle but important reproductive flaws transmitted from the female gonads to the offspring with the NO involvement. Despite a recovery along time after the bloom, insidious damages can be envisaged in the local sea urchin population, with possible reverberation on the whole benthic system.

Does infertility history affect the emotional adjustment of couples undergoing assisted reproduction? the mediating role of the importance of parenthood.

PubMed

Moura-Ramos, Mariana; Gameiro, Sofia; Canavarro, Maria Cristina; Soares, Isabel; Almeida-Santos, Teresa

2016-05-01

The emotional adjustment of couples undergoing assisted reproductive technology (ART) treatments has been widely studied; however, it remains unclear whether infertility history contributes to couples' adjustment. This study examined the impact of infertility history (duration of infertility and number of previous ART treatment cycles) on the emotional adjustment of couples undergoing an ART cycle and the mediating effect of importance of parenthood on that association. In this cross-sectional study, 70 infertile couples (70 women and 70 men) completed self-report questionnaires assessing emotional adjustment and infertility stress during the hormonal stimulation phase of an ART cycle. Path models accounting for the dyadic nature of the data examined the direct and indirect effects (by affecting representations about parenthood and childlessness) of infertility history on emotional adjustment. The number of previous cycles affected men's, but not women's, emotional adjustment by affecting the representations on the importance of parenthood and of childlessness. Duration of infertility had the opposite effect, as couples with longer infertility reported heightened importance of parenthood, which negatively affected their emotional adjustment. Infertility history was associated with emotional adjustment in men and women, although these associations were complex. The results suggest that progression through treatment is harder for those men and women who attribute higher importance to being parents, which is aggravated by longer infertility. What is already known about the subject? Infertility is an unexpected and stressful life event Assisted reproductive treatments (ART) are emotionally demanding What does this study add? The influence of infertility history on adjustment is mediated by the importance of parenthood Men and women are affected by their past history of infertility differently. © 2015 The Authors. British Journal of Health Psychology published by John

Neuroendocrine integration of nutritional signals on reproduction.

PubMed

Evans, Maggie C; Anderson, Greg M

2017-02-01

Reproductive function in mammals is energetically costly and therefore tightly regulated by nutritional status. To enable this integration of metabolic and reproductive function, information regarding peripheral nutritional status must be relayed centrally to the gonadotropin-releasing hormone (GNRH) neurons that drive reproductive function. The metabolically relevant hormones leptin, insulin and ghrelin have been identified as key mediators of this 'metabolic control of fertility'. However, the neural circuitry through which they act to exert their control over GNRH drive remains incompletely understood. With the advent of Cre-LoxP technology, it has become possible to perform targeted gene-deletion and gene-rescue experiments and thus test the functional requirement and sufficiency, respectively, of discrete hormone-neuron signaling pathways in the metabolic control of reproductive function. This review discusses the findings from these investigations, and attempts to put them in context with what is known from clinical situations and wild-type animal models. What emerges from this discussion is clear evidence that the integration of nutritional signals on reproduction is complex and highly redundant, and therefore, surprisingly difficult to perturb. Consequently, the deletion of individual hormone-neuron signaling pathways often fails to cause reproductive phenotypes, despite strong evidence that the targeted pathway plays a role under normal physiological conditions. Although transgenic studies rarely reveal a critical role for discrete signaling pathways, they nevertheless prove to be a good strategy for identifying whether a targeted pathway is absolutely required, critically involved, sufficient or dispensable in the metabolic control of fertility. © 2017 Society for Endocrinology.

Neonicotinoid insecticides negatively affect performance measures of non‐target terrestrial arthropods: a meta‐analysis

USGS Publications Warehouse

Main, Anson; Webb, Elisabeth B.; Goyne, Keith W.; Mengel, Doreen C.

2018-01-01

Neonicotinoid insecticides are currently the fastest‐growing and most widely used insecticide class worldwide. Valued for their versatility in application, these insecticides may cause deleterious effects in a range of non‐target (beneficial) arthropods. However, it remains unclear whether strong patterns exist in terms of their major effects, if broad measures of arthropod performance are negatively affected, or whether different functional groups are equally vulnerable. Here, we present a meta‐analysis of 372 observations from 44 field and laboratory studies that describe neonicotinoid effects on 14 arthropod orders across five broad performance measures: abundance, behavior, condition, reproductive success, and survival. Across studies, neonicotinoids negatively affected all performance metrics evaluated; however, magnitude of the effects varied. Arthropod behavior and survival were the most negatively affected and abundance was the least negatively affected. Effects on arthropod functional groups were inconsistent. Pollinator condition, reproductive success, and survival were significantly lower in neonicotinoid treatments compared to untreated controls; whereas, neonicotinoid effects on detritivores were not significant. Although magnitude of arthropod response to neonicotinoids varied among performance measures and functional groups, we documented a consistent negative relationship between exposure to neonicotinoid insecticides in published studies and beneficial arthropod performance.

Interannual variability of growth and reproduction in Bursera simaruba: the role of allometry and resource variability.

PubMed

Hulshof, Catherine M; Stegen, James C; Swenson, Nathan G; Enquist, Carolyn A F; Enquist, Brian J

2012-01-01

Plants are expected to differentially allocate resources to reproduction, growth, and survival in order to maximize overall fitness. Life history theory predicts that the allocation of resources to reproduction should occur at the expense of vegetative growth. Although it is known that both organism size and resource availability can influence life history traits, few studies have addressed how size dependencies of growth and reproduction and variation in resource supply jointly affect the coupling between growth and reproduction. In order to understand the relationship between growth and reproduction in the context of resource variability, we utilize a long-term observational data set consisting of 670 individual trees over a 10-year period within a local population of Bursera simaruba (L.) Sarg. We (1) quantify the functional form and variability in the growth-reproduction relationship at the population and individual-tree level and (2) develop a theoretical framework to understand the allometric dependence of growth and reproduction. Our findings suggest that the differential responses of allometric growth and reproduction to resource availability, both between years and between microsites, underlie the apparent relationship between growth and reproduction. Finally, we offer an alternative approach for quantifying the relationship between growth and reproduction that accounts for variation in allometries.

Chapter 11.18 - Neuroendocrine Control of Female Reproduction.

EPA Science Inventory

The hypothalamus and pituitary are known to play roles in reproductive function. A growing body of evidence indicates that environmental toxicants can alter female reproductive function by disrupting hypothalamic control of the pituitary and subsequently the endocrine control of ...

Role of Oxidative Stress in Male Reproductive Dysfunctions with Reference to Phthalate Compounds.

PubMed

Sedha, Sapna; Kumar, Sunil; Shukla, Shruti

2015-11-14

A wide variety of environmental chemicals/xenobiotics including phthalates have been shown to cause oxidative stress targeting the endocrine system and cause reproductive anomalies. The present review describes various issues by oxidative stress causing male reproductive dysfunctions. Here in this review, the importance and role of phthalate compounds in male reproductive dysfunction has been well documented. One class of environmental endocrine disruptors is phthalates. Phthalate compounds are mostly used as plasticizers, which increase the flexibility, durability, longevity, and etc. of the plastics. Large-scale use of plastic products in our daily life as well as thousands of workers engaged in the manufacture of plastic and plastic products and recycling plastic industry are potentially exposed to these chemicals. Further, general population as well as vulnerable groups i.e. children and pregnant women are also exposed to these chemicals. Phthalates are among wide variety of environmental toxicants capable of compromising male fertility by inducing a state of oxidative stress in the testes. They may also generate reactive oxygen species (ROS) that may affect various physiological and reproductive functions. The available data points out that phthalate compounds may also induce oxidative stress in the male reproductive organs mainly testis and epididymis. They impair spermatogenic process by inducing oxidative stress and apoptosis in germ cells or target sertoli cells and thereby hamper spermatogenesis. They also impair the Leydig cell function by inducing ROS, thereby decreasing the levels of steroidogenic enzymes. Thus in utero and postnatal exposure to phthalate compounds might lead to decreased sperm count and various other reproductive anomalies in the young male.

Sperm protection in the male reproductive tract by Toll-like receptors.

PubMed

Saeidi, S; Shapouri, F; Amirchaghmaghi, E; Hoseinifar, H; Sabbaghian, M; Sadighi Gilani, M A; Pacey, A A; Aflatoonian, R

2014-09-01

Sperm function can be affected by infection. Our understanding of innate immune system molecular mechanisms has been expanded, by the discovery of 'Toll-like receptors' (TLRs). It seems that these receptors could play a critical role in the protection of spermatozoa. This study seeks to examine the presence and distribution of TLRs in different parts of the human male reproductive tract and spermatozoa. So, TLR gene expression was examined by RT-PCR. Quantitative real-time PCR (Q-PCR) analysis used to compare the expression of TLRs in all sections of the male reproductive tract and TLRs 2, 3 and 4 in testicular sperm extraction (TESE) samples, which contained spermatozoa (TESE+) and those that did not (TESE-). Results showed that all TLR genes were expressed in different parts of the human male reproductive tract and spermatozoa. Moreover, Q-PCR indicated that the relative expression of TLRs did not significantly change in different parts of the male reproductive tract but this technique has shown only relative TLR2 expression in TESE- is lower than TESE+ samples. It could be concluded that TLRs may provide a broad spectrum of protection from infection in the male reproductive tract. Furthermore, TLRs may influence on the developmental process during spermatogenesis. © 2013 Blackwell Verlag GmbH.

Estimating finite-population reproductive numbers in heterogeneous populations.

PubMed

Keegan, Lindsay T; Dushoff, Jonathan

2016-05-21

The basic reproductive number, R0, is one of the most important epidemiological quantities. R0 provides a threshold for elimination and determines when a disease can spread or when a disease will die out. Classically, R0 is calculated assuming an infinite population of identical hosts. Previous work has shown that heterogeneity in the host mixing rate increases R0 in an infinite population. However, it has been suggested that in a finite population, heterogeneity in the mixing rate may actually decrease the finite-population reproductive numbers. Here, we outline a framework for discussing different types of heterogeneity in disease parameters, and how these affect disease spread and control. We calculate "finite-population reproductive numbers" with different types of heterogeneity, and show that in a finite population, heterogeneity has complicated effects on the reproductive number. We find that simple heterogeneity decreases the finite-population reproductive number, whereas heterogeneity in the intrinsic mixing rate (which affects both infectiousness and susceptibility) increases the finite-population reproductive number when R0 is small relative to the size of the population and decreases the finite-population reproductive number when R0 is large relative to the size of the population. Although heterogeneity has complicated effects on the finite-population reproductive numbers, its implications for control are straightforward: when R0 is large relative to the size of the population, heterogeneity decreases the finite-population reproductive numbers, making disease control or elimination easier than predicted by R0. Copyright © 2016 Elsevier Ltd. All rights reserved.

Individual heterogeneity and offspring sex affect the growth-reproduction trade-off in a mammal with indeterminate growth.

PubMed

Gélin, Uriel; Wilson, Michelle E; Cripps, Jemma; Coulson, Graeme; Festa-Bianchet, Marco

2016-04-01

Reproduction can lead to a trade-off with growth, particularly when individuals reproduce before completing body growth. Kangaroos have indeterminate growth and may always face this trade-off. We combined an experimental manipulation of reproductive effort and multi-year monitoring of a large sample size of marked individuals in two populations of eastern grey kangaroos to test the predictions (1) that reproduction decreases skeletal growth and mass gain and (2) that mass loss leads to reproductive failure. We also tested if sex-allocation strategies influenced these trade-offs. Experimental reproductive suppression revealed negative effects of reproduction on mass gain and leg growth from 1 year to the next. Unmanipulated females, however, showed a positive correlation between number of days lactating and leg growth over periods of 2 years and longer, suggesting that over the long term, reproductive costs were masked by individual heterogeneity in resource acquisition. Mass gain was necessary for reproductive success the subsequent year. Although mothers of daughters generally lost more mass than females nursing sons, mothers in poor condition experienced greater mass gain and arm growth if they had daughters than if they had sons. The strong links between individual mass changes and reproduction suggest that reproductive tactics are strongly resource-dependent.

Mitochondrial functionality in reproduction: from gonads and gametes to embryos and embryonic stem cells.

PubMed

Ramalho-Santos, João; Varum, Sandra; Amaral, Sandra; Mota, Paula C; Sousa, Ana Paula; Amaral, Alexandra

2009-01-01

Mitochondria are multitasking organelles involved in ATP synthesis, reactive oxygen species (ROS) production, calcium signalling and apoptosis; and mitochondrial defects are known to cause physiological dysfunction, including infertility. The goal of this review was to identify and discuss common themes in mitochondrial function related to mammalian reproduction. The scientific literature was searched for studies reporting on the several aspects of mitochondrial activity in mammalian testis, sperm, oocytes, early embryos and embryonic stem cells. ATP synthesis and ROS production are the most discussed aspects of mitochondrial function. Metabolic shifts from mitochondria-produced ATP to glycolysis occur at several stages, notably during gametogenesis and early embryo development, either reflecting developmental switches or substrate availability. The exact role of sperm mitochondria is especially controversial. Mitochondria-generated ROS function in signalling but are mostly described when produced under pathological conditions. Mitochondria-based calcium signalling is primarily important in embryo activation and embryonic stem cell differentiation. Besides pathologically triggered apoptosis, mitochondria participate in apoptotic events related to the regulation of spermatogonial cell number, as well as gamete, embryo and embryonic stem cell quality. Interestingly, data from knock-out (KO) mice is not always straightforward in terms of expected phenotypes. Finally, recent data suggests that mitochondrial activity can modulate embryonic stem cell pluripotency as well as differentiation into distinct cellular fates. Mitochondria-based events regulate different aspects of reproductive function, but these are not uniform throughout the several systems reviewed. Low mitochondrial activity seems a feature of 'stemness', being described in spermatogonia, early embryo, inner cell mass cells and embryonic stem cells.

Evolution of reproductive proteins from animals and plants.

PubMed

Clark, Nathaniel L; Aagaard, Jan E; Swanson, Willie J

2006-01-01

Sexual reproduction is a fundamental biological process common among eukaryotes. Because of the significance of reproductive proteins to fitness, the diversity and rapid divergence of proteins acting at many stages of reproduction is surprising and suggests a role of adaptive diversification in reproductive protein evolution. Here we review the evolution of reproductive proteins acting at different stages of reproduction among animals and plants, emphasizing common patterns. Although we are just beginning to understand these patterns, by making comparisons among stages of reproduction for diverse organisms we can begin to understand the selective forces driving reproductive protein diversity and the functional consequences of reproductive protein evolution.

The reproduction in women affected by cooley disease

PubMed Central

Pafumi, Carlo; Leanza, Vito; Coco, Luana; Vizzini, Stefania; Ciotta, Lilliana; Messina, Alessandra; Leanza, Gianluca; Zarbo, Giuseppe; D'Agati, Alfio; Palumbo, Marco Antonio; Iemmola, Alessandra; Gulino, Ferdinando Antonio; Teodoro, Maria Cristina; Attard, Matthew; Plesca, Alina Cristina; Soares, Catarina; Kouloubis, Nina; Chammas, Mayada

2011-01-01

The health background management and outcomes of 5 pregnancies in 4 women affected by Cooley Disease, from Paediatric Institute of Catania University, are described, considering the preconceptual guidances and cares for such patients. These patients were selected among a group of 100 thalassemic women divided into three subgroups, according to their first and successive menstruation characteristics: i) patients with primitive amenorrhoea, ii) patients with secondary amenorrhoea and iii) patients with normal menstruation. Only one woman, affected by primitive amenorrhoea, needed the induction of ovulation. A precise and detailed pre-pregnancy assessment was effected before each conception. This was constituted by a series of essays, including checks for diabetes and hypothyroidism, for B and C hepatitis and for blood group antibodies. Moreover were evaluated: cardiac function, rubella immunity and transaminases. Other pregnancy monitoring, and cares during labour and delivery were effected according to usual obstetrics practice. All the women were in labour when she were 38 week pregnant, and the outcome were five healthy babies born at term, weighting between 2600 and 3200gs. The only complication was the Caesarean section. The improvements of current treatments, especially in the management of iron deposits, the prolongation of survival rate, will result in a continuous increase of pregnancies in thalassemic women. Pregnancy is now a real possibility for women affected by such disease. We are furthermore studying the possibility to collect the fetus' umbilical cord blood, after the delivery, to attempt eterologus transplantation to his mother trying to get a complete marrow reconstitution. PMID:22184526

THE ESTROGENIC AND ANTIANDROGENIC PESTICIDE METHOXYCHLOR ALTERS THE REPRODUCTIVE TRACT AND BEHAVIOR WITHOUT AFFECTING PITUITARY SIZE OR LH AND PROLACTIN SECRETION IN MALE RATS

EPA Science Inventory

The estrogenic and antiandrogenic pesticide methoxychlor alters the reproductive tract and behavior without affecting pituitary size or LH and prolactin secretion in male rats.

Gray LE Jr, Ostby J, Cooper RL, Kelce WR.

Endocrinology Branch, United States Environment...

A nationwide study on reproductive function, ovarian reserve, and risk of premature menopause in female survivors of childhood cancer: design and methodological challenges.

PubMed

Overbeek, Annelies; van den Berg, Marleen H; Kremer, Leontien C M; van den Heuvel-Eibrink, Marry M; Tissing, Wim J E; Loonen, Jacqueline J; Versluys, Birgitta; Bresters, Dorine; Kaspers, Gertjan J L; Lambalk, Cornelis B; van Leeuwen, Flora E; van Dulmen-den Broeder, Eline

2012-08-23

Advances in childhood cancer treatment over the past decades have significantly improved survival, resulting in a rapidly growing group of survivors. However, both chemo- and radiotherapy may adversely affect reproductive function. This paper describes the design and encountered methodological challenges of a nationwide study in the Netherlands investigating the effects of treatment on reproductive function, ovarian reserve, premature menopause and pregnancy outcomes in female childhood cancer survivors (CCS), the DCOG LATER-VEVO study. The study is a retrospective cohort study consisting of two parts: a questionnaire assessing medical, menstrual, and obstetric history, and a clinical assessment evaluating ovarian and uterine function by hormonal analyses and transvaginal ultrasound measurements. The eligible study population consists of adult female 5-year survivors of childhood cancer treated in the Netherlands, whereas the control group consists of age-matched sisters of the participating CCS. To date, study invitations have been sent to 1611 CCS and 429 sister controls, of which 1215 (75%) and 333 (78%) have responded so far. Of these responders, the majority consented to participate in both parts of the study (53% vs. 65% for CCS and sister controls respectively). Several challenges were encountered involving the study population: dealing with bias due to the differences in characteristics of several types of (non-) participants and finding an adequately sized and well-matched control group. Moreover, the challenges related to the data collection process included: differences in response rates between web-based and paper-based questionnaires, validity of self-reported outcomes, interpretation of clinical measurements of women using hormonal contraceptives, and inter- and intra-observer variation of the ultrasound measurements. The DCOG LATER-VEVO study will provide valuable information about the reproductive potential of paediatric cancer patients as well as

Successful Reproduction Requires the Function of Arabidopsis YELLOW STRIPE-LIKE1 and YELLOW STRIPE-LIKE3 Metal-Nicotianamine Transporters in Both Vegetative and Reproductive Structures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chu, H.; Chiecko, J; Punshon, T

2010-01-01

Several members of the Yellow Stripe-Like (YSL) family of proteins are transporters of metals that are bound to the metal chelator nicotianamine or the related set of mugineic acid family chelators known as phytosiderophores. Here, we examine the physiological functions of three closely related Arabidopsis (Arabidopsis thaliana) YSL family members, AtYSL1, AtYSL2, and AtYSL3, to elucidate their role(s) in the allocation of metals into various organs of Arabidopsis. We show that AtYSL3 and AtYSL1 are localized to the plasma membrane and function as iron transporters in yeast functional complementation assays. By using inflorescence grafting, we show that AtYSL1 and AtYSL3more » have dual roles in reproduction: their activity in the leaves is required for normal fertility and normal seed development, while activity in the inflorescences themselves is required for proper loading of metals into the seeds. We further demonstrate that the AtYSL1 and AtYSL2 proteins, when expressed from the AtYSL3 promoter, can only partially rescue the phenotypes of a ysl1ysl3 double mutant, suggesting that although these three YSL transporters are closely related and have similar patterns of expression, they have distinct activities in planta. In particular, neither AtYSL1 nor AtYSL2 is able to functionally complement the reproductive defects exhibited by ysl1ysl3 double mutant plants.« less

The MADS-box gene SlMBP11 regulates plant architecture and affects reproductive development in tomato plants.

PubMed

Guo, Xuhu; Chen, Guoping; Naeem, Muhammad; Yu, Xiaohu; Tang, Boyan; Li, Anzhou; Hu, Zongli

2017-05-01

MADS-domain proteins are important transcription factors that are involved in many biological processes of plants. In the present study, SlMBP11, a member of the AGL15 subfamily, was cloned in tomato plants (Solanum lycopersicon M.). SlMBP11 is ubiquitously expressed in all of the tissues we examined, whereas the SlMBP11 transcription levels were significantly higher in reproductive tissues than in vegetative tissues. Plants exhibiting increased SlMBP11 levels displayed reduced plant height, leaf size, and internode length as well as a loss of dominance in young seedlings, highly branched growth from each leaf axil, and increased number of nodes and leaves. Moreover, overexpression lines also exhibited reproductive phenotypes, such as those having a shorter style and split ovary, leading to polycarpous fruits, while the wild type showed normal floral organization. In addition, delayed perianth senescence was observed in transgenic tomatoes. These phenotypes were further confirmed by analyzing the morphological, anatomical and molecular features of lines exhibiting overexpression. These results suggest that SlMBP11 plays an important role in regulating plant architecture and reproductive development in tomato plants. These findings add a new class of transcription factors to the group of genes controlling axillary bud growth and illuminate a previously uncharacterized function of MADS-box genes in tomato plants. Copyright © 2017 Elsevier B.V. All rights reserved.

Honey Bee (Apis mellifera) Queen Reproductive Potential Affects Queen Mandibular Gland Pheromone Composition and Worker Retinue Response

PubMed Central

Böröczky, Katalin; Schal, Coby; Tarpy, David R.

2016-01-01

Reproductive division of labor is one of the defining traits of honey bees (Apis mellifera), with non-reproductive tasks being performed by workers while a single queen normally monopolizes reproduction. The decentralized organization of a honey bee colony is maintained in large part by a bouquet of queen-produced pheromones, the distribution of which is facilitated by contact among workers throughout the hive. Previous studies have shown that the developmental fate of honey bee queens is highly plastic, with queens raised from younger worker larvae exhibiting higher measures of reproductive potential compared to queens raised from older worker larvae. We investigated differences in the chemical composition of the mandibular glands and attractiveness to workers of “high-quality” queens (i.e., raised from first instar worker larvae; more queen-like) and “low-quality” queens (i.e., raised from third instar worker larvae; more worker-like). We characterized the chemical profiles of the mandibular glands of high-quality queens and low-quality queens using GC-MS and used the worker retinue response as a measure of the attractiveness to workers of high-quality queens vs. low-quality queens. We found that queen quality affected the chemical profiles of mandibular gland contents differently across years, showing significant differences in the production of the queen mandibular pheromone (“QMP”) components HVA and 9-HDA in 2010, but no significant differences of any glandular compound in 2012. We also found that workers were significantly more attracted to high-quality queens than to low-quality queens in 2012, possibly because of increased attractiveness of their mandibular gland chemical profiles. Our results indicate that the age at which honey bee larvae enter the “queen-specific” developmental pathway influences the chemical composition of queen mandibular glands and worker behavior. However, these changes are not consistent across years, suggesting

The concentration of plasma metabolites varies throughout reproduction and affects offspring number in wild brown trout (Salmo trutta).

PubMed

Gauthey, Zoé; Freychet, Marine; Manicki, Aurélie; Herman, Alexandre; Lepais, Olivier; Panserat, Stéphane; Elosegi, Arturo; Tentelier, Cédric; Labonne, Jacques

2015-06-01

In wild populations, measuring energy invested in the reproduction and disentangling investment in gametes versus investment in reproductive behavior (such as intrasexual competition or intersexual preference) remain challenging. In this study, we investigated the energy expenditure in brown trout reproductive behavior by using two proxies: variation in weight and variation of plasma metabolites involved in energy production, over the course of reproductive season in a semi natural experimental river. We estimated overall reproductive success using genetic assignment at the end of the reproductive season. Results show that triglycerides and free fatty acid concentrations vary negatively during reproduction, while amino-acids and glucose concentrations remain stable. Decrease in triglyceride and free fatty acid concentrations during reproduction is not related to initial concentration levels or to weight variation. Both metabolite concentration variations and weight variations are correlated to the number of offspring produced, which could indicate that gametic and behavioral reproductive investments substantially contribute to reproductive success in wild brown trout. This study opens a path to further investigate variations in reproductive investment in wild populations. Copyright © 2015 Elsevier Inc. All rights reserved.

Activins in reproductive biology and beyond.

PubMed

Wijayarathna, R; de Kretser, D M

2016-04-01

reproductive aging. In the male, activin A is an autocrine and paracrine modulator of germ cell development and Sertoli cell proliferation. Disruption of normal activin signalling is characteristic of many tumours affecting reproductive organs, including endometrial carcinoma, cervical cancer, testicular and ovarian cancer as well as prostate cancer. While activin A and B aid the progression of many tumours of the reproductive organs, activin C acts as a tumour suppressor. Activins are important in embryonic induction, morphogenesis of branched glandular organs, development of limbs and nervous system, craniofacial and dental development and morphogenesis of the Wolffian duct. The field of activin biology has advanced considerably since its initial discovery as an FSH stimulating agent. Now, activin is well known as a growth factor and cytokine that regulates many aspects of reproductive biology, developmental biology and also inflammation and immunological mechanisms. Current research provides evidence for novel roles of activins in maintaining the structure and function of reproductive and other organ systems. The fact that activin A is elevated both locally as well as systemically in major disorders of the reproductive system makes it an important biomarker. Given the established role of activin A as a pro-inflammatory and pro-fibrotic agent, studies of its involvement in disorders of reproduction resulting from these processes should be examined. Follistatin, as a key regulator of the biological actions of activin, should be evaluated as a therapeutic agent in conditions where activin A overexpression is established as a contributing factor. © The Author 2016. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Functional characterization of an apple apomixis-related MhFIE gene in reproduction development.

PubMed

Liu, Dan-Dan; Dong, Qing-Long; Sun, Chao; Wang, Qing-Lian; You, Chun-Xiang; Yao, Yu-Xin; Hao, Yu-Jin

2012-04-01

The products of the FIS genes play important regulatory roles in diverse developmental processes, especially in seed formation after fertilization. In this study, a FIS-class gene MhFIE was isolated from apple. It encoded a predicted protein highly similar to polycomb group (PcG) protein FERTILIZATION-INDEPENDENT ENDOSPERM (FIE). MhFIE functioned as an Arabidopsis FIE homologue, as indicated by functional complementation experiment using Arabidopsis fie mutant. In addition, BiFC assay showed that MhFIE protein interacted with AtCLF. Furthermore, transgenic Arabidopsis ectopically expressing MhFIE produced less APETALA3 (AtAP3) and AGAMOUS (AtAG) transcripts than WT control, and therefore exhibited abnormal flower, seed development. These results suggested that polycomb complex including FIE and CLF proteins played an important role in reproductive development by regulating the expression of its downstream genes. In addition, it was found that MhFIE constitutively expressed in various tissues tested. Its expression levels were lower in apomictic apple species than the sexual reproductive species, suggested it was possibly involved into apomixis in apple. Furthermore, the hybrids of tea crabapple generated MhFIE transcripts at different levels. The parthenogenesis capacity was negatively correlated with MhFIE expression level in these hybrids. These results suggested that MhFIE was involved into the regulation of flower development and apomixis in apple. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

Leptin and reproduction: a review.

PubMed

Moschos, Stergios; Chan, Jean L; Mantzoros, Christos S

2002-03-01

To review recent advances in understanding the role of leptin in the physiology and pathophysiology of reproduction, with a focus on relevant clinical situations. A MEDLINE computer search was performed to identify relevant articles. Leptin, an adipocyte hormone important in regulating energy homeostasis, interacts with the reproductive axis at multiple sites, with stimulatory effects at the hypothalamus and pituitary and inhibitory actions at the gonads. More recently, leptin has been shown to play a role in other target reproductive organs, such as the endometrium, placenta, and mammary gland, with corresponding influences on important physiologic processes such as menstruation, pregnancy, and lactation. As a marker of whether nutritional stores are adequate, leptin may act in concert with gonadotropins and the growth hormone axis to initiate the complex process of puberty. Conditions in which nutritional status is suboptimal, such as eating disorders, exercise-induced amenorrhea, and functional hypothalamic amenorrhea, are associated with low serum leptin levels; and conditions with excess energy stores or metabolic disturbances, such as obesity and polycystic ovarian syndrome, often have elevated serum or follicular fluid leptin levels, raising the possibility that relative leptin deficiency or resistance may be at least partly responsible for the reproductive abnormalities that occur with these conditions. Leptin may act as the critical link between adipose tissue and the reproductive system, indicating whether adequate energy reserves are present for normal reproductive function. Future interventional studies involving leptin administration are expected to further clarify this role of leptin and may provide new therapeutic options for the reproductive dysfunction associated with states of relative leptin deficiency or resistance.

Sexual experience affects reproductive behavior and preoptic androgen receptors in male mice

PubMed Central

Swaney, William T.; Dubose, Brittany N.; Curley, James P.; Champagne, Frances A.

2012-01-01

Reproductive behavior in male rodents is made up of anticipatory and consummatory elements which are regulated in the brain by sensory systems, reward circuits and hormone signaling. Gonadal steroids play a key role in the regulation of male sexual behavior via steroid receptors in the hypothalamus and preoptic area. Typical patterns of male reproductive behavior have been characterized, however these are not fixed but are modulated by adult experience. We assessed the effects of repeated sexual experience on male reproductive behavior of C57BL/6 mice; including measures of olfactory investigation of females, mounting, intromission and ejaculation. The effects of sexual experience on the number of cells expressing either androgen receptor (AR) or estrogen receptor alpha (ERα) in the primary brain nuclei regulating male sexual behavior was also measured. Sexually experienced male mice engaged in less sniffing of females before initiating sexual behavior and exhibited shorter latencies to mount and intromit, increased frequency of intromission, and increased duration of intromission relative to mounting. No changes in numbers of ERα-positive cells were observed, however sexually experienced males had increased numbers of AR-positive cells in the medial preoptic area (MPOA); the primary regulatory nucleus for male sexual behavior. These results indicate that sexual experience results in a qualitative change in male reproductive behavior in mice that is associated with increased testosterone sensitivity in the MPOA and that this nucleus may play a key integrative role in mediating the effects of sexual experience on male behavior. PMID:22266118

Masturbation Frequency and Sexual Function Domains Are Associated With Serum Reproductive Hormone Levels Across the Menopausal Transition

PubMed Central

Zheng, Huiyong; Avis, Nancy E.; Greendale, Gail A.; Harlow, Siobán D.

2015-01-01

Objective: To determine whether reproductive hormones are related to sexual function during the menopausal transition. Design: The Study of Women's Health Across the Nation (SWAN) is a multiethnic cohort study of the menopausal transition located at seven US sites. At baseline, the 3302 community-based participants, aged 42–52, had an intact uterus and at least one ovary and were not using exogenous hormones. Participants self-identified as White, Black, Hispanic, Chinese, or Japanese. At baseline and at each of the 10 follow-up visits, sexual function was assessed by self-administered questionnaires, and blood was drawn to assay serum levels of T, estradiol, FSH, SHBG, and dehydroepiandrosterone sulfate. Main Outcome Measures: Self-reported frequency of masturbation, sexual desire, sexual arousal, orgasm, and pain during intercourse. Results: Masturbation, sexual desire, and arousal were positively associated with T. Masturbation, arousal, and orgasm were negatively associated with FSH. Associations were modest. Estradiol was not related to any measured sexual function domain. Pain with intercourse was not associated with any hormone. Conclusions: Reproductive hormones were associated with sexual function in midlife women. T was positively associated, supporting the role of androgens in female sexual function. FSH was negatively associated, supporting the role of menopausal status in female sexual function. The modest associations in this large study suggest that the relationships are subtle and may be of limited clinical significance. PMID:25412335

Masturbation frequency and sexual function domains are associated with serum reproductive hormone levels across the menopausal transition.

PubMed

Randolph, John F; Zheng, Huiyong; Avis, Nancy E; Greendale, Gail A; Harlow, Siobán D

2015-01-01

To determine whether reproductive hormones are related to sexual function during the menopausal transition. The Study of Women's Health Across the Nation (SWAN) is a multiethnic cohort study of the menopausal transition located at seven US sites. At baseline, the 3302 community-based participants, aged 42-52, had an intact uterus and at least one ovary and were not using exogenous hormones. Participants self-identified as White, Black, Hispanic, Chinese, or Japanese. At baseline and at each of the 10 follow-up visits, sexual function was assessed by self-administered questionnaires, and blood was drawn to assay serum levels of T, estradiol, FSH, SHBG, and dehydroepiandrosterone sulfate. Self-reported frequency of masturbation, sexual desire, sexual arousal, orgasm, and pain during intercourse. Masturbation, sexual desire, and arousal were positively associated with T. Masturbation, arousal, and orgasm were negatively associated with FSH. Associations were modest. Estradiol was not related to any measured sexual function domain. Pain with intercourse was not associated with any hormone. Reproductive hormones were associated with sexual function in midlife women. T was positively associated, supporting the role of androgens in female sexual function. FSH was negatively associated, supporting the role of menopausal status in female sexual function. The modest associations in this large study suggest that the relationships are subtle and may be of limited clinical significance.

Multiple roles of the prostaglandin D2 signaling pathway in reproduction.

PubMed

Rossitto, Moïra; Ujjan, Safdar; Poulat, Francis; Boizet-Bonhoure, Brigitte

2015-01-01

Prostaglandins signaling molecules are involved in numerous physiological processes. They are produced by several enzyme-limited reactions upon fatty acids, which are catalyzed by two cyclooxygenases and prostaglandin synthases. In particular, the prostaglandins E2 (PGE2), D2 (PGD2), and F2 (PGF2 α) have been shown to be involved in female reproductive mechanisms. Furthermore, widespread expression of lipocalin- and hematopoietic-PGD2 synthases in the male reproductive tract supports the purported roles of PGD2 in the development of both embryonic and adult testes, sperm maturation, and spermatogenesis. In this review, we summarize the putative roles of PGD2 signaling and the roles of both PGD2 synthases in testicular formation and function. We review the data reporting the involvement of PGD2 signaling in the differentiation of Sertoli and germ cells of the embryonic testis. Furthermore, we discuss the roles of lipocalin-PGD2 synthase in steroidogenesis and spermatogenesis, in terms of lipid molecule transport and PGD2 production. Finally, we discuss the hypothesis that PGD2 signaling may be affected in certain reproductive diseases, such as infertility, cryptorchidism, and testicular cancer. © 2015 Society for Reproduction and Fertility.

Reproductive health concerns in six conflict-affected areas of Sri Lanka.

PubMed

Kottegoda, Sepali; Samuel, Kumudini; Emmanuel, Sarala

2008-05-01

This article draws on a study conducted by the Women and Media Collective between 2004 and 2005 to highlight some of the reproductive health concerns of women from Sinhalese, Tamil and Muslim ethnic groups, living in situations of conflict in Sri Lanka. The study focussed on women from six conflict-affected areas in the north and east of the country: Jaffna (Northern Province), Mannar and Puttalam (North-Western Province), Polonnaruwa (North-Central Province), Batticaloa and Ampara (Eastern Province). Higher levels of poverty, higher rates of school drop-out, low pay and precarious access to work, mainly in the informal sector, higher rates of early marriage, pregnancy and home births, higher levels of maternal mortality and lower levels of contraceptive use were found. Economic, social and physical insecurity were key to these phenomena. Physically and psychologically, women were at high risk of sexual and physical violence, mainly from their partners/spouses but also from family members, often related to dowry. The article brings out the voices of women whose lives have been overshadowed by conflict and displacement, and the nature of structural barriers that impede their right to health care services, to make informed decisions about their lives and to live free of familial violence.

Reproductive isolation between populations of Iris atropurpurea is associated with ecological differentiation

PubMed Central

Yardeni, Gil; Tessler, Naama; Imbert, Eric; Sapir, Yuval

2016-01-01

Background and Aims Speciation is often described as a continuous dynamic process, expressed by different magnitudes of reproductive isolation (RI) among groups in different levels of divergence. Studying intraspecific partial RI can shed light on mechanisms underlying processes of population divergence. Intraspecific divergence can be driven by spatially stochastic accumulation of genetic differences following reduced gene flow, resulting in increased RI with increased geographical distance, or by local adaptation, resulting in increased RI with environmental difference. Methods We tested for RI as a function of both geographical distance and ecological differentiation in Iris atropurpurea, an endemic Israeli coastal plant. We crossed plants in the Netanya Iris Reserve population with plants from 14 populations across the species’ full distribution, and calculated RI and reproductive success based on fruit set, seed set and fraction of seed viability. Key Results We found that total RI was not significantly associated with geographical distance, but significantly increased with ecological distance. Similarly, reproductive success of the crosses, estimated while controlling for the dependency of each component on the previous stage, significantly reduced with increased ecological distance. Conclusions Our results indicate that the rise of post-pollination reproductive barriers in I. atropurpurea is more affected by ecological differentiation between populations than by geographical distance, supporting the hypothesis that ecological differentiation is predominant over isolation by distance and by reduced gene flow in this species. These findings also affect conservation management, such as genetic rescue, in the highly fragmented and endangered I. atropurpurea. PMID:27436798

The relationship between gut and adipose hormones, and reproduction.

PubMed

Comninos, Alexander N; Jayasena, Channa N; Dhillo, Waljit S

2014-01-01

Reproductive function is tightly regulated by nutritional status. Indeed, it has been well described that undernutrition or obesity can lead to subfertility or infertility in humans. The common regulatory pathways which control energy homeostasis and reproductive function have, to date, been poorly understood due to limited studies or inconclusive data. However, gut hormones and adipose tissue hormones have recently emerged as potential regulators of both energy homeostasis and reproductive function. A PubMed search was performed using keywords related to gut and adipose hormones and associated with keywords related to reproduction. Currently available evidence that gut (ghrelin, obestatin, insulin, peptide YY, glucagon-like peptide-1, glucose-dependent insulinotropic peptide, oxyntomodulin, cholecystokinin) and adipose hormones (leptin, adiponectin, resistin, omentin, chemerin) interact with the reproductive axis is presented. The extent, site and direction of their effects on the reproductive axis are variable and also vary depending on species, sex and pubertal stage. Gut and adipose hormones interact with the reproductive axis as well as with each other. While leptin and insulin have stimulatory effects and ghrelin has inhibitory effects on hypothalamic GnRH secretion, there is increasing evidence for their roles in other sites of the reproductive axis as well as evidence for the roles of other gut and adipose hormones in the complex interplay between nutrition and reproduction. As our understanding improves, so will our ability to identify and design novel therapeutic options for reproductive disorders and accompanying metabolic disorders.

Juvenile hormone, but not nutrition or social cues, affects reproductive maturation in solitary alkali bees (Nomia melanderi).

PubMed

Kapheim, Karen M; Johnson, Makenna M

2017-10-15

Eusocial insect colonies are defined by extreme variation in reproductive activity among castes, but the ancestral conditions from which this variation arose are unknown. Investigating the factors that contribute to variation in reproductive physiology among solitary insects that are closely related to social species can help to fill this gap. We experimentally tested the role of nutrition, juvenile hormone (JH) and social cues on reproductive maturation in solitary alkali bees (Halictidae: Nomia melanderi ). We found that alkali bee females emerge from overwintering with small Dufour's glands and small ovaries, containing oocytes in the early stages of development. Oocyte maturation occurs rapidly, and is staggered between the two ovaries. Lab-reared females reached reproductive maturity without access to mates or nesting opportunities, and many had resorbed oocytes. Initial activation of these reproductive structures does not depend on pollen consumption, though dietary protein or lipids may be necessary for long-term reproductive activity. JH is likely to be a limiting factor in alkali bee reproductive activation, as females treated with JH were more likely to develop mature oocytes and Dufour's glands. Unlike for related social bees, the effects of JH were not suppressed by the presence of older, reproductive females. These results provide valuable insight into the factors that influence reproductive activity in an important native pollinator, and those that may have been particularly influential in the evolution of reproductive castes. © 2017. Published by The Company of Biologists Ltd.

Body composition and reproductive function exert unique influences on indices of bone health in exercising women.

PubMed

Mallinson, Rebecca J; Williams, Nancy I; Hill, Brenna R; De Souza, Mary Jane

2013-09-01

Reproductive function, metabolic hormones, and lean mass have been observed to influence bone metabolism and bone mass. It is unclear, however, if reproductive, metabolic and body composition factors play unique roles in the clinical measures of areal bone mineral density (aBMD) and bone geometry in exercising women. This study compares lumbar spine bone mineral apparent density (BMAD) and estimates of femoral neck cross-sectional moment of inertia (CSMI) and cross-sectional area (CSA) between exercising ovulatory (Ov) and amenorrheic (Amen) women. It also explores the respective roles of reproductive function, metabolic status, and body composition on aBMD, lumbar spine BMAD and femoral neck CSMI and CSA, which are surrogate measures of bone strength. Among exercising women aged 18-30 years, body composition, aBMD, and estimates of femoral neck CSMI and CSA were assessed by dual-energy x-ray absorptiometry. Lumbar spine BMAD was calculated from bone mineral content and area. Estrone-1-glucuronide (E1G) and pregnanediol glucuronide were measured in daily urine samples collected for one cycle or monitoring period. Fasting blood samples were collected for measurement of leptin and total triiodothyronine. Ov (n = 37) and Amen (n = 45) women aged 22.3 ± 0.5 years did not differ in body mass, body mass index, and lean mass; however, Ov women had significantly higher percent body fat than Amen women. Lumbar spine aBMD and BMAD were significantly lower in Amen women compared to Ov women (p < 0.001); however, femoral neck CSA and CSMI were not different between groups. E1G cycle mean and age of menarche were the strongest predictors of lumbar spine aBMD and BMAD, together explaining 25.5% and 22.7% of the variance, respectively. Lean mass was the strongest predictor of total hip and femoral neck aBMD as well as femoral neck CSMI and CSA, explaining 8.5-34.8% of the variance. Upon consideration of several potential osteogenic stimuli, reproductive function appears to play

How do reproductive skew and founder group size affect genetic diversity in reintroduced populations?

PubMed

Miller, K A; Nelson, N J; Smith, H G; Moore, J A

2009-09-01

Reduced genetic diversity can result in short-term decreases in fitness and reduced adaptive potential, which may lead to an increased extinction risk. Therefore, maintaining genetic variation is important for the short- and long-term success of reintroduced populations. Here, we evaluate how founder group size and variance in male reproductive success influence the long-term maintenance of genetic diversity after reintroduction. We used microsatellite data to quantify the loss of heterozygosity and allelic diversity in the founder groups from three reintroductions of tuatara (Sphenodon), the sole living representatives of the reptilian order Rhynchocephalia. We then estimated the maintenance of genetic diversity over 400 years (approximately 10 generations) using population viability analyses. Reproduction of tuatara is highly skewed, with as few as 30% of males mating across years. Predicted losses of heterozygosity over 10 generations were low (1-14%), and populations founded with more animals retained a greater proportion of the heterozygosity and allelic diversity of their source populations and founder groups. Greater male reproductive skew led to greater predicted losses of genetic diversity over 10 generations, but only accelerated the loss of genetic diversity at small population size (<250 animals). A reduction in reproductive skew at low density may facilitate the maintenance of genetic diversity in small reintroduced populations. If reproductive skew is high and density-independent, larger founder groups could be released to achieve genetic goals for management.

A High Fat Diet during Adolescence in Male Rats Negatively Programs Reproductive and Metabolic Function Which Is Partially Ameliorated by Exercise

PubMed Central

Ibáñez, Carlos A.; Erthal, Rafaela P.; Ogo, Fernanda M.; Peres, Maria N. C.; Vieira, Henrique R.; Conejo, Camila; Tófolo, Laize P.; Francisco, Flávio A.; da Silva Silveira, Sandra; Malta, Ananda; Pavanello, Audrei; Martins, Isabela P.; da Silva, Paulo H. O.; Jacinto Saavedra, Lucas Paulo; Gonçalves, Gessica D.; Moreira, Veridiana M.; Alves, Vander S.; da Silva Franco, Claudinéia C.; Previate, Carina; Gomes, Rodrigo M.; de Oliveira Venci, Renan; Dias, Francielle R. S.; Armitage, James A.; Zambrano, Elena; Mathias, Paulo C. F.; Fernandes, Glaura S. A.; Palma-Rigo, Kesia

2017-01-01

An interaction between obesity, impaired glucose metabolism and sperm function in adults has been observed but it is not known whether exposure to a diet high in fat during the peri-pubertal period can have longstanding programmed effects on reproductive function and gonadal structure. This study examined metabolic and reproductive function in obese rats programmed by exposure to a high fat (HF) diet during adolescence. The effect of physical training (Ex) in ameliorating this phenotype was also assessed. Thirty-day-old male Wistar rats were fed a HF diet (35% lard w/w) for 30 days then subsequently fed a normal fat diet (NF) for a 40-day recovery period. Control animals were fed a NF diet throughout life. At 70 days of life, animals started a low frequency moderate exercise training that lasted 30 days. Control animals remained sedentary (Se). At 100 days of life, biometric, metabolic and reproductive parameters were evaluated. Animals exposed to HF diet showed greater body weight, glucose intolerance, increased fat tissue deposition, reduced VO2max and reduced energy expenditure. Consumption of the HF diet led to an increase in the number of abnormal seminiferous tubule and a reduction in seminiferous epithelium height and seminiferous tubular diameter, which was reversed by moderate exercise. Compared with the NF-Se group, a high fat diet decreased the number of seminiferous tubules in stages VII-VIII and the NF-Ex group showed an increase in stages XI-XIII. HF-Se and NF-Ex animals showed a decreased number of spermatozoa in the cauda epididymis compared with animals from the NF-Se group. Animals exposed to both treatments (HF and Ex) were similar to all the other groups, thus these alterations induced by HF or Ex alone were partially prevented. Physical training reduced fat pad deposition and restored altered reproductive parameters. HF diet consumption during the peri-pubertal period induces long-term changes on metabolism and the reproductive system, but

A High Fat Diet during Adolescence in Male Rats Negatively Programs Reproductive and Metabolic Function Which Is Partially Ameliorated by Exercise.

PubMed

Ibáñez, Carlos A; Erthal, Rafaela P; Ogo, Fernanda M; Peres, Maria N C; Vieira, Henrique R; Conejo, Camila; Tófolo, Laize P; Francisco, Flávio A; da Silva Silveira, Sandra; Malta, Ananda; Pavanello, Audrei; Martins, Isabela P; da Silva, Paulo H O; Jacinto Saavedra, Lucas Paulo; Gonçalves, Gessica D; Moreira, Veridiana M; Alves, Vander S; da Silva Franco, Claudinéia C; Previate, Carina; Gomes, Rodrigo M; de Oliveira Venci, Renan; Dias, Francielle R S; Armitage, James A; Zambrano, Elena; Mathias, Paulo C F; Fernandes, Glaura S A; Palma-Rigo, Kesia

2017-01-01

An interaction between obesity, impaired glucose metabolism and sperm function in adults has been observed but it is not known whether exposure to a diet high in fat during the peri-pubertal period can have longstanding programmed effects on reproductive function and gonadal structure. This study examined metabolic and reproductive function in obese rats programmed by exposure to a high fat (HF) diet during adolescence. The effect of physical training (Ex) in ameliorating this phenotype was also assessed. Thirty-day-old male Wistar rats were fed a HF diet (35% lard w/w) for 30 days then subsequently fed a normal fat diet (NF) for a 40-day recovery period. Control animals were fed a NF diet throughout life. At 70 days of life, animals started a low frequency moderate exercise training that lasted 30 days. Control animals remained sedentary (Se). At 100 days of life, biometric, metabolic and reproductive parameters were evaluated. Animals exposed to HF diet showed greater body weight, glucose intolerance, increased fat tissue deposition, reduced VO 2max and reduced energy expenditure. Consumption of the HF diet led to an increase in the number of abnormal seminiferous tubule and a reduction in seminiferous epithelium height and seminiferous tubular diameter, which was reversed by moderate exercise. Compared with the NF-Se group, a high fat diet decreased the number of seminiferous tubules in stages VII-VIII and the NF-Ex group showed an increase in stages XI-XIII. HF-Se and NF-Ex animals showed a decreased number of spermatozoa in the cauda epididymis compared with animals from the NF-Se group. Animals exposed to both treatments (HF and Ex) were similar to all the other groups, thus these alterations induced by HF or Ex alone were partially prevented. Physical training reduced fat pad deposition and restored altered reproductive parameters. HF diet consumption during the peri-pubertal period induces long-term changes on metabolism and the reproductive system, but

Effects of bisphenol A on male and couple reproductive health: a review.

PubMed

Mínguez-Alarcón, Lidia; Hauser, Russ; Gaskins, Audrey J

2016-09-15

Bisphenol A (BPA) is a ubiquitous environmental toxicant with endocrine-disrupting properties and is suspected to affect human reproduction. The objective of this review was to summarize the potential effects of male exposure to BPA on markers of testicular function and couple reproductive outcomes. Five epidemiologic studies on BPA and reproductive hormones all found significant associations with at least one reproductive hormone; however, no consistent relationships were observed across studies. Six epidemiologic studies evaluated the relation between BPA and semen parameters, and although the majority reported negative associations with various parameters, there were few consistent trends across studies. Finally, three epidemiologic studies examined BPA and couple reproductive outcomes, and only one found an association. Overall, the evidence supporting an association between BPA exposure and adverse male reproductive health outcomes in humans remains limited and inconclusive. Reasons for the discrepancies in results could include, but are not limited to, differences in study populations (e.g., fertile vs. subfertile men), BPA urinary concentrations (occupationally vs. nonoccupationally exposed), misclassification of BPA exposure (e.g., using one urine sample to characterize exposure vs. multiple samples), sample sizes, study design (e.g., cross-sectional vs. prospective), and residual confounding (e.g., due to diet and lifestyle factors). It is also possible that some of the statistically significant findings were due to chance alone. Clearly, further studies are needed to further clarify the role of this ubiquitous endocrine-disrupting chemical on male reproductive health. Copyright © 2016. Published by Elsevier Inc.

Plant reproduction in spaceflight environments

NASA Technical Reports Server (NTRS)

Musgrave, M. E.; Kuang, A.; Porterfield, D. M.

1997-01-01

Because plant reproduction is a complex developmental process there are many possible sites of perturbation by the unusual environments of orbital spacecraft. Previous long-duration experiments on Soviet platforms shared features of slowed development through the vegetative stage of plant growth and aborted reproductive function. Our goal has been to understand how special features of the spaceflight environment impact physiological function and reproductive development. In a series of short-duration experiments in the Shuttle mid-deck we studied early reproductive development in Arabidopsis thaliana. Pollen and ovule development aborted at an early stage in the first experiment on STS-54 which utilized closed plant growth chambers. Post-flight analysis suggested that the plants may have been carbon dioxide limited. Subsequent experiments utilized carbon dioxide enrichment (on STS-51) and cabin air flow-through with an air exchange system (on STS-68). Both modifications allowed pollen and ovule development to occur normally on orbit, and full reproductive development up to the stage of an immature seed occurred on STS-68. However, analysis of plant roots from these experiments demonstrated a limitation in rootzone aeration in the spaceflight material that was not mitigated by these procedures. In the future, additional resources (crew time, upgraded flight hardware, and special platforms) will invite more elaborate, long-duration experimentation. On the ISS, a variable speed centrifuge and upgraded plant habitats will permit detailed experiments on the role of gravity in shaping the plant micro-environment, and what influence this plays during reproduction.

A widely employed germ cell marker is an ancient disordered protein with reproductive functions in diverse eukaryotes

PubMed Central

Carmell, Michelle A; Dokshin, Gregoriy A; Skaletsky, Helen; Hu, Yueh-Chiang; van Wolfswinkel, Josien C; Igarashi, Kyomi J; Bellott, Daniel W; Nefedov, Michael; Reddien, Peter W; Enders, George C; Uversky, Vladimir N; Mello, Craig C; Page, David C

2016-01-01

The advent of sexual reproduction and the evolution of a dedicated germline in multicellular organisms are critical landmarks in eukaryotic evolution. We report an ancient family of GCNA (germ cell nuclear antigen) proteins that arose in the earliest eukaryotes, and feature a rapidly evolving intrinsically disordered region (IDR). Phylogenetic analysis reveals that GCNA proteins emerged before the major eukaryotic lineages diverged; GCNA predates the origin of a dedicated germline by a billion years. Gcna gene expression is enriched in reproductive cells across eukarya – either just prior to or during meiosis in single-celled eukaryotes, and in stem cells and germ cells of diverse multicellular animals. Studies of Gcna-mutant C. elegans and mice indicate that GCNA has functioned in reproduction for at least 600 million years. Homology to IDR-containing proteins implicated in DNA damage repair suggests that GCNA proteins may protect the genomic integrity of cells carrying a heritable genome. DOI: http://dx.doi.org/10.7554/eLife.19993.001 PMID:27718356

Developmental exposure of zebrafish (Danio rerio) to 17α-ethinylestradiol affects non-reproductive behavior and fertility as adults, and increases anxiety in unexposed progeny.

PubMed

Volkova, Kristina; Reyhanian Caspillo, Nasim; Porseryd, Tove; Hallgren, Stefan; Dinnétz, Patrik; Porsch-Hällström, Inger

2015-07-01

Exposure to estrogenic endocrine disruptors (EDCs) during development affects fertility, reproductive and non-reproductive behavior in mammals and fish. These effects can also be transferred to coming generations. In fish, the effects of developmental EDC exposure on non-reproductive behavior are less well studied. Here, we analyze the effects of 17α-ethinylestradiol (EE2) on anxiety, shoaling behavior and fertility in zebrafish after developmental treatment and remediation in clean water until adulthood. Zebrafish embryos were exposed from day 1 to day 80 post fertilization to actual concentrations of 1.2 and 1.6ng/L EE2. After remediation for 82days non-reproductive behavior and fertilization success were analyzed in both sexes. Males and females from the 1.2ng/L group, as well as control males and females, were bred, and behavior of the untreated F1 offspring was tested as adults. Developmental treatment with 1.2 and 1.6ng/L EE2 significantly increased anxiety in the novel tank test and increased shoaling intensity in both sexes. Fertilization success was significantly reduced by EE2 in both sexes when mated with untreated fish of opposite sex. Progeny of fish treated with 1.2ng/L EE2 showed increased anxiety in the novel tank test and increased light avoidance in the scototaxis test compared to control offspring. In conclusion, developmental exposure of zebrafish to low doses of EE2 resulted in persistent changes in behavior and fertility. The behavior of unexposed progeny was affected by their parents' exposure, which might suggest transgenerational effects. Copyright © 2015. Published by Elsevier Inc.

Reproduction reduces photosynthetic capacity in females of the subdioecious Honckenya peploides

NASA Astrophysics Data System (ADS)

Sánchez-Vilas, Julia; Retuerto, Rubén

2011-03-01

As a consequence of the different reproductive functions performed by the sexes, sexually dimorphic/polymorphic plants may exhibit gender-related variations in the energy and resources allocated to reproduction, and in the physiological processes that underlie these differences. This study investigated whether the sexes of the subdioecious plant Honckenya peploides differ in ecophysiological traits related to photosynthetic capacity and whether possible differences depend on reproductive status and on the plant's position (edge or centre) in the population. We registered in three sites in NW Spain, the sex and density of shoots of two segregated clumps of plants. These clumps represent an extreme case of sex-ratio variation across space, with separated single-sex clumps of plants. In two of these sites we measured photosynthetic efficiencies, chlorophyll content, and specific leaf areas. In females, reproduction reduced photochemical efficiency, chlorophyll content and increased the specific leaf area, which is a key leaf trait related to photosynthetic capacity. In males, no differences due to reproduction were detected. The position within the clump affected the specific leaf area of the shoots, with shoots growing at the edge having the lowest values, regardless of the sex. Finally, the effects of position in photosynthetic efficiency and chlorophyll content where highly variable among clumps. We conclude that the differential effects of reproduction on sexes may entail different costs that could be crucial in the outcome of interactions between them, contributing to their spatial segregation.

Methylxanthines and reproduction.

PubMed

Minelli, Alba; Bellezza, Ilaria

2011-01-01

Reproduction is the process by which organisms create descendants. In human reproduction, two kinds of sex cells, or gametes, are involved. Sperm, the male gamete, and egg egg , or ovum ovum Vedi egg , the female gamete, must meet in the female reproductive system to create a new individual and both the female and the male reproductive systems are essential to the occurrence of reproduction. Scientific reports dealing with the effects of methylxanthines on reproduction are mostly centred on the use of these compounds as phosphodiesterase inhibitors that, by maintaining high intracellular levels of cyclic AMP (cAMP) cyclic AMP , will affect the gametes differently. High cAMP levels will sustain sperm sperm maturation while they hold the oocytes in mitotic arrest. Caffeine caffeine , being the methylxanthine most widely consumed by every segment of the population, has been the subject of greatest interest among health professionals and researchers. Conflicting results still seem to characterize the association between male/female caffeine caffeine consumption in adult life and semen quality/fertility fertility , although moderate daily caffeine consumption of levels up to 400-450 mg/day (5.7-6.4 mg/kg/day in a 70-kg adult) do not seem to be associated with adverse effects, i.e. general toxicity, effects on bone status and calcium balance, cardiovascular effects, behavioural changes, increased incidence of cancer, or effects on male fertility. A clear stimulation of egg-laying by the coffee leaf pest Leucoptera coffeella was recently reported, providing support for the hypothesis that caffeine, in a dose-dependent way, in insects stimulates egg-laying, thus leading to the death of coffee trees.

The effects of kisspeptin in human reproductive function - therapeutic implications.

PubMed

Ratnasabapathy, Risheka; Dhillo, Waljit S

2013-03-01

Kisspeptin is a 54-amino acid peptide which is encoded by the KiSS-1 gene and activates the G protein-coupled receptor GPR54. Evidence suggests that this system is a key regulator of mammalian and human reproduction. Animal studies have shown that GPR54-deficient mice have abnormal sexual development. Central and peripheral administration of kisspeptin stimulates the hypothalamic-pituitary-gonadal (HPG) axis whilst pre-administration of a gonadotrophin releasing hormone (GnRH) antagonist abolishes this effect. In humans, inactivating GPR54 mutations cause normosmic hypogonadotrophic hypogonadism whilst activation of GPR54 signalling is associated with premature puberty. In healthy human volunteers, the acute intravenous administration of kisspeptin potently increases plasma luteinising hormone (LH) levels and significantly increases plasma follicle stimulating hormone (FSH) and testosterone without side effects in both males and in females particularly in the preovulatatory phase of the menstrual cycle. In infertility due to hypothalamic amenorrhoea acute administration of kisspeptin results in stimulation of reproductive hormones. The kisspeptin/GPR54 system therefore appears to play an important role in the regulation of reproduction in humans. Hence kisspeptin has potential as a novel tool for the manipulation of the HPG axis and treatment of infertility in humans. This review discusses the evidence highlighting kisspeptin's key role in human reproduction.

Metabolic influences on neuroendocrine regulation of reproduction.

PubMed

Navarro, Víctor M; Kaiser, Ursula B

2013-08-01

Reproduction is a tightly regulated function in which many mechanisms contribute to ensure the survival of the species. Among those, due to the elevated energy requirements of reproduction, metabolic factors exert a pivotal role in the control of hypothalamic-pituitary-gonadal axis. Although this control may occur at multiple levels of the axis, the majority of interactions between metabolic and reproductive systems take place in the hypothalamus. In this article, we present an overview of the state-of-the-art knowledge regarding the metabolic regulation of reproduction at the central level. We aim to identify the neuroanatomical location where both functions interconnect by discussing the likelihood of each component of the neuronal hierarchical network controlling gonadotropin-releasing hormone (GnRH) release to be first-order responders to metabolic cues, especially the peripheral metabolic signals leptin, insulin, and ghrelin. Latest evidence suggests that the primary action of leptin, insulin, and ghrelin to regulate reproduction is located upstream of the main central elicitors of gonadotropin release, Kiss1 and GnRH neurons, and neuroanatomically separated from their metabolic action. The study of the neuronal interactions between the mechanisms governing metabolism and reproduction offers the platform to overcome or treat a number of prevailing metabolic and/or reproductive conditions.

Lysophosphatidic Acid (LPA) Signaling in Human and Ruminant Reproductive Tract

PubMed Central

Wocławek-Potocka, Izabela; Rawińska, Paulina; Kowalczyk-Zieba, Ilona; Boruszewska, Dorota; Sinderewicz, Emilia; Waśniewski, Tomasz; Skarzynski, Dariusz Jan

2014-01-01

Lysophosphatidic acid (LPA) through activating its G protein-coupled receptors (LPAR 1–6) exerts diverse cellular effects that in turn influence several physiological processes including reproductive function of the female. Studies in various species of animals and also in humans have identified important roles for the receptor-mediated LPA signaling in multiple aspects of human and animal reproductive tract function. These aspects range from ovarian and uterine function, estrous cycle regulation, early embryo development, embryo implantation, decidualization to pregnancy maintenance and parturition. LPA signaling can also have pathological consequences, influencing aspects of endometriosis and reproductive tissue associated tumors. The review describes recent progress in LPA signaling research relevant to human and ruminant reproduction, pointing at the cow as a relevant model to study LPA influence on the human reproductive performance. PMID:24744506

High temperatures result in smaller nurseries which lower reproduction of pollinators and parasites in a brood site pollination mutualism.

PubMed

Krishnan, Anusha; Pramanik, Gautam Kumar; Revadi, Santosh V; Venkateswaran, Vignesh; Borges, Renee M

2014-01-01

In a nursery pollination mutualism, we asked whether environmental factors affected reproduction of mutualistic pollinators, non-mutualistic parasites and seed production via seasonal changes in plant traits such as inflorescence size and within-tree reproductive phenology. We examined seasonal variation in reproduction in Ficus racemosa community members that utilise enclosed inflorescences called syconia as nurseries. Temperature, relative humidity and rainfall defined four seasons: winter; hot days, cold nights; summer and wet seasons. Syconium volumes were highest in winter and lowest in summer, and affected syconium contents positively across all seasons. Greater transpiration from the nurseries was possibly responsible for smaller syconia in summer. The 3-5°C increase in mean temperatures between the cooler seasons and summer reduced fig wasp reproduction and increased seed production nearly two-fold. Yet, seed and pollinator progeny production were never negatively related in any season confirming the mutualistic fig-pollinator association across seasons. Non-pollinator parasites affected seed production negatively in some seasons, but had a surprisingly positive relationship with pollinators in most seasons. While within-tree reproductive phenology did not vary across seasons, its effect on syconium inhabitants varied with season. In all seasons, within-tree reproductive asynchrony affected parasite reproduction negatively, whereas it had a positive effect on pollinator reproduction in winter and a negative effect in summer. Seasonally variable syconium volumes probably caused the differential effect of within-tree reproductive phenology on pollinator reproduction. Within-tree reproductive asynchrony itself was positively affected by intra-tree variation in syconium contents and volume, creating a unique feedback loop which varied across seasons. Therefore, nursery size affected fig wasp reproduction, seed production and within-tree reproductive phenology

The male reproductive system - An overview of common problems.

PubMed

Wijesinha, Sanjiva; Piterman, Leon; Kirby, Catherine N

2013-05-01

Many male reproductive system problems could be perceived as being embarrassing, which may be one of the reasons that they are often not identified in general practice. This article provides an overview of some common problems affecting the male reproductive system, and outlines current treatment options. Erectile dysfunction, premature ejaculation, loss of libido, testicular cancer and prostate disease may cause embarrassment to the patient and, occasionally, the general practitioner. We describe how patients affected by these conditions may present to general practice, and discuss the reasons why they may not present. We also discuss how GPs can overcome difficulties in identifying and dealing with their male patients suffering from male reproductive system issues.

Administration of melatonin protects against acetylsalicylic acid-induced impairment of male reproductive function in mice

PubMed Central

Emami, Niloufar Hedayati; Lafout, Farzaneh Mahmoudi; Mohammadghasemi, Fahimeh

2018-01-01

Objective(s): Melatonin, an important hormone secreted by the epiphysis, is a powerful anti-oxidant with a high potential to neutralize medical toxins. The goal of this study was to demonstrate the beneficial effect of melatonin on epididymal sperm and reproductive parameters in mice treated with acetylsalicylic acid (ASA). Materials and Methods: Male adult mice were divided into four treatment groups: control, ASA, melatonin, and ASA+melatonin. Mice were administered ASA (50 mg/kg, orally) and/or melatonin (10 mg/kg, intraperitoneally), or vehicle control, for 14 days. Sperm count, sperm motility, and sperm morphology were evaluated to assess fertility. A colorimetric assay was used to measure serum total antioxidant capacity (TAC). A sperm chromatin dispersion (SCD) test was used to assess sperm chromatin integrity. Sex hormone levels were measured by ELISA. Results: Compared to the control group, ASA treatment resulted in a significant decrease in sperm parameters (P<0.05), as well as a decrease in the integrity of sperm chromatin (P<0.01). ASA treatment also reduced serum testosterone and TAC levels (P<0.05). Co-administration of melatonin with ASA significantly improved epididymal sperm parameters and increased serum testosterone and TAC levels compared to the ASA-treated group. LH level was not different in the combined treatment group compared to control or ASA treatment. Conclusion: Short-term administration of ASA (50 mg/kg) has adverse effects on male reproductive function in mice. Co-administration of melatonin protects against ASA-induced impairment of male reproductive function by preventing the reduction in serum TAC and testosterone levels seen with ASA treatment alone. PMID:29456808

Modeling adverse environmental impacts on the reproductive system.

PubMed

Sussman, N B; Mazumdar, S; Mattison, D R

1999-03-01

When priority topics are being established for the study of women's health, it is generally agreed that one important area on which to focus research is reproduction. For example, increasing attention has been directed to environmental exposures that disrupt the endocrine system and alter reproduction. These concerns also suggest the need to give greater attention to the use of animal toxicologic testing to draw inferences about human reproductive risks. Successful reproduction requires multiple simultaneous and sequential processes in both the male and female, and the effect of toxicity on reproduction-related processes is time dependent. Currently, however, the risk assessment approach does not allow for the use of multiple processes or for considering the reproductive process response as a function of time. We discuss several issues in modeling exposure effects on reproductive function for risk assessment and present an overview of approaches for reproductive risk assessment. Recommendations are provided for an effective animal study design for determining reproductive risk that addresses optimization of the duration of dosing, observation of the effects of exposure on validated biomarkers, analysis of several biomarkers for complete characterization of the exposure on the underlying biologic processes, the need for longitudinally observed exposure effects, and a procedure for estimating human reproductive risk from the animal findings. An approach to characterizing reproductive toxicity to estimate the increased fertility risks in a dibromochloropropane (DBCP)-exposed human population is illustrated, using several reproductive biomarkers simultaneously from a longitudinal rabbit inhalation study of DBCP and an interspecies extrapolation method.

In vitro functional screening as a means to identify new plasticizers devoid of reproductive toxicity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Boisvert, Annie; Jones, Steven; Issop, Leeyah

reproduction. • Reproductive toxicity of new plasticizers was assessed by functional assays. • Mouse Leydig and germ cell lines, and rat perinatal testis cultures were used. • Survival, proliferation, steroidogenesis, abnormal germ cell formation were examined. • Reproductive toxic and innocuous plasticizer candidates were identified.« less

Reproductive Issues in Women with Turner Syndrome

PubMed Central

Folsom, Lisal J.; Fuqua, John S.

2016-01-01

Synopsis Turner syndrome is one of the most common chromosomal abnormalities affecting female infants. The severity of clinical manifestations generally varies and affects multiple organ systems. Women with Turner syndrome have a threefold increase in mortality, which becomes even more pronounced in pregnancy. There are several reproductive options available for women with Turner syndrome, including adoption or surrogacy, assisted reproductive techniques, and in rare cases spontaneous pregnancy. There are well-documented risks for women with Turner syndrome during pregnancy, including specific risks of aortic pathology, hepatic disease, thyroid disease, type 2 diabetes, and Cesarean section delivery. Several professional societies have published guidelines to aid in the care of women with Turner syndrome prior to and during pregnancy. It is important for providers who care for these women to be familiar with the specific risks and recommendations in caring for women with Turner syndrome of reproductive age. PMID:26568488

[Advances in the study of neuroendocrinological regulation of kisspeptin in fish reproduction].

PubMed

Zhuo, Qi

2013-10-01

Kisspeptin, a key factor in the neuroendocrinological regulation of animal reproduction, is a peptide product encoded by kiss genes, which act as the natural ligand of GPR54. Over the last decade, multiple functional molecular forms of kisspeptin have been found in vertebrate species. In fish, the major molecular structural form is kisspeptin-10. The kisspeptin/GPR54 system has multiple important functions in reproduction. This review provides an overview of our current knowledge on kisspeptin and its role in regulating fish reproductive, including the distribution and location of kisspeptin neurons in the brain, the molecular polymorphism of fish kisspeptin, functional diversity, the molecular mechanism of fish reproductive regulation, and the molecular evolution of kisspeptin as well as the co-regulation of fish reproduction by kisspeptin and other functional molecules. Perspectives on the future of kisspeptin regulation in fish reproduction are also highlighted.

Mortality affects adaptive allocation to growth and reproduction: field evidence from a guild of body snatchers

PubMed Central

2010-01-01

Background The probability of being killed by external factors (extrinsic mortality) should influence how individuals allocate limited resources to the competing processes of growth and reproduction. Increased extrinsic mortality should select for decreased allocation to growth and for increased reproductive effort. This study presents perhaps the first clear cross-species test of this hypothesis, capitalizing on the unique properties offered by a diverse guild of parasitic castrators (body snatchers). I quantify growth, reproductive effort, and expected extrinsic mortality for several species that, despite being different species, use the same species' phenotype for growth and survival. These are eight trematode parasitic castrators—the individuals of which infect and take over the bodies of the same host species—and their uninfected host, the California horn snail. Results As predicted, across species, growth decreased with increased extrinsic mortality, while reproductive effort increased with increased extrinsic mortality. The trematode parasitic castrator species (operating stolen host bodies) that were more likely to be killed by dominant species allocated less to growth and relatively more to current reproduction than did species with greater life expectancies. Both genders of uninfected snails fit into the patterns observed for the parasitic castrator species, allocating as much to growth and to current reproduction as expected given their probability of reproductive death (castration by trematode parasites). Additionally, species differences appeared to represent species-specific adaptations, not general plastic responses to local mortality risk. Conclusions Broadly, this research illustrates that parasitic castrator guilds can allow unique comparative tests discerning the forces promoting adaptive evolution. The specific findings of this study support the hypothesis that extrinsic mortality influences species differences in growth and reproduction

Identifying environmental risk to male reproductive function by occupational sperm studies: logistics and design options.

PubMed Central

Bonde, J P; Giwercman, A; Ernst, E

1996-01-01

Malfunction of the male reproductive system might be a sensitive marker of environmental hazards, the effects of which may extend beyond reproductive function. The testis is more vulnerable to heat and ionising radiation than any other organ of the body and several xenobiotics are known to disrupt spermatogenesis after low level exposure. Studies of environmental impact on human health are often most informative and accurate when carried out in the workplace where exposures can be high and easy to document. Semen analysis provides readily obtainable information on testicular function. The main advantages in comparison with functional measures such as fertility rates and time taken to conceive are the possibilities to examine men independently of marriage and pregnancy, to find changes of fecundity with different exposures within the same person and to detect adverse effects when no alteration of fertility is yet taking place. In the implementation of an occupational sperm study considerable attention must be paid to logistic issues. A mobile laboratory unit for initial semen preparation and processing may in some situations increase worker compliance and the quality of sperm cell motility. The cross sectional design which has been used in almost all male reproductive studies so far has several severe limitations including selection bias because of differential participation, difficulties in defining a suitable reference group, and lack of information about the time dimension of the cause-effect relation. The longitudinal design deals adequately with most of these constraints. Semen samples are collected before, during, and possibly after exposure to the risk factor of interest and causal inferences are based upon change of semen variables within a man over time rather than upon differences between men. The logistics of the longitudinal study may benefit from pre-employment health examinations to enrol newly hired workers and require fewer participants to obtain

Role of granulocyte colony-stimulating factor in human reproduction.

PubMed

Eftekhar, Maryam; Naghshineh, Elham; Khani, Parisa

2018-01-01

As new research reveals, granulocyte colony-stimulating factor (G-CSF) plays an effective role in pregnancy success, considering that it not only affects the embryo implantation and ovarian function but also it promotes endometrial thickening and improves the pathophysiology of endometriosis, which all fundamentally lead to reducing pregnancy loss. In this review, we focus on the role of G-CSF in human reproduction. We summarized its role in ovulation, luteinized unruptured follicle syndrome, poor responders, improving repeated in vitro fertilization failure, endometrial receptivity and treatment of thin endometrium, and recurrent spontaneous abortion.

Reproductive physiology

USGS Publications Warehouse

Gee, G.F.; Russman, S.E.; Ellis, David H.; Gee, George F.; Mirande, Claire M.

1996-01-01

Conclusions: Although the general pattern of avian physiology applies to cranes, we have identified many physiological mechanisms (e.g., effects of disturbance) that need further study. Studies with cranes are expensive compared to those done with domestic fowl because of the crane's larger size, low reproductive rate, and delayed sexual maturity. To summarize, the crane reproductive system is composed of physiological and anatomical elements whose function is controlled by an integrated neural-endocrine system. Males generally produce semen at a younger age than when females lay eggs. Eggs are laid in clutches of two (1 to 3), and females will lay additional clutches if the preceding clutches are removed. Both sexes build nests and incubate the eggs. Molt begins during incubation and body molt may be completed annually in breeding pairs. However, remiges are replaced sequentially over 2 to 3 years, or abruptly every 2 to 3 years in other species. Most immature birds replace their juvenal remiges over a 2 to 3 year period. Stress interferes with reproduction in cranes by reducing egg production or terminating the reproductive effort. In other birds, stress elevates corticosterone levels and decreases LHRH release. We know little about the physiological response of cranes to stress.

Reproductive disorders associated with pesticide exposure.

PubMed

Frazier, Linda M

2007-01-01

Exposure of men or women to certain pesticides at sufficient doses may increase the risk for sperm abnormalities, decreased fertility, a deficit of male children, spontaneous abortion, birth defects or fetal growth retardation. Pesticides from workplace or environmental exposures enter breast milk. Certain pesticides have been linked to developmental neurobehavioral problems, altered function of immune cells and possibly childhood leukemia. In well-designed epidemiologic studies, adverse reproductive or developmental effects have been associated with mixed pesticide exposure in occupational settings, particularly when personal protective equipment is not used. Every class of pesticides has at least one agent capable of affecting a reproductive or developmental endpoint in laboratory animals or people, including organophosphates, carbamates, pyrethroids, herbicides, fungicides, fumigants and especially organochlorines. Many of the most toxic pesticides have been banned or restricted in developed nations, but high exposures to these agents are still occurring in the most impoverished countries around the globe. Protective clothing, masks and gloves are more difficult to tolerate in hot, humid weather, or may be unavailable or unaffordable. Counseling patients who are concerned about reproductive and developmental effects of pesticides often involves helping them assess their exposure levels, weigh risks and benefits, and adopt practices to reduce or eliminate their absorbed dose. Patients may not realize that by the first prenatal care visit, most disruptions of organogenesis have already occurred. Planning ahead provides the best chance of lowering risk from pesticides and remediating other risk factors before conception.

Developmental Exposure to Ethinylestradiol Affects Reproductive Physiology, the GnRH Neuroendocrine Network and Behaviors in Female Mouse.

PubMed

Derouiche, Lyes; Keller, Matthieu; Martini, Mariangela; Duittoz, Anne H; Pillon, Delphine

2015-01-01

During development, environmental estrogens are able to induce an estrogen mimetic action that may interfere with endocrine and neuroendocrine systems. The present study investigated the effects on the reproductive function in female mice following developmental exposure to pharmaceutical ethinylestradiol (EE2), the most widespread and potent synthetic steroid present in aquatic environments. EE2 was administrated in drinking water at environmentally relevant (ENVIR) or pharmacological (PHARMACO) doses [0.1 and 1 μg/kg (body weight)/day respectively], from embryonic day 10 until postnatal day 40. Our results show that both groups of EE2-exposed females had advanced vaginal opening and shorter estrus cycles, but a normal fertility rate compared to CONTROL females. The hypothalamic population of GnRH neurons was affected by EE2 exposure with a significant increase in the number of perikarya in the preoptic area of the PHARMACO group and a modification in their distribution in the ENVIR group, both associated with a marked decrease in GnRH fibers immunoreactivity in the median eminence. In EE2-exposed females, behavioral tests highlighted a disturbed maternal behavior, a higher lordosis response, a lack of discrimination between gonad-intact and castrated males in sexually experienced females, and an increased anxiety-related behavior. Altogether, these results put emphasis on the high sensitivity of sexually dimorphic behaviors and neuroendocrine circuits to disruptive effects of EDCs.

Women, war, and reproductive health in developing countries.

PubMed

Pillai, Vijayan; Wang, Ya-Chien; Maleku, Arati

2017-01-01

Globally, millions of people are affected by war and conflicts every year. However, women have increasingly suffered the greatest harm by war in more different ways than men. We conceptualize a reproductive rights approach toward examining the effects of war on women's reproductive health in developing countries. Given the rising concerns of exclusion to adequately address women's rights, sexual and gender-based violence, and post-conflict accountability, we specifically focus on the limitations of the Minimum Initial Service Package, a UN-sponsored reproductive health service program in conflict zones while offering a broad reproductive rights-based conceptual lens for examining reproductive health care services in war-torn areas. In addition, we discuss the roles social workers may play at both micro and macro levels in war-torn areas to bring about both short term and long term gains in women's reproductive health.

Male reproductive health and yoga

PubMed Central

Sengupta, Pallav; Chaudhuri, Prasenjit; Bhattacharya, Koushik

2013-01-01

Now-a-days reproductive health problems along with infertility in male is very often observed. Various Assisted Reproductive Technologies have been introduced to solve the problem, but common people cannot afford the cost of such procedures. Various ayurvedic and other alternative medicines, along with regular yoga practice are proven to be not only effective to enhance the reproductive health in men to produce a successful pregnancy, but also to regulate sexual desire in men who practice celibacy. Yoga is reported to reduce stress and anxiety, improve autonomic functions by triggering neurohormonal mechanisms by the suppression of sympathetic activity, and even, today, several reports suggested regular yoga practice from childhood is beneficial for reproductive health. In this regard the present review is aimed to provide all the necessary information regarding the effectiveness of yoga practice to have a better reproductive health and to prevent infertility. PMID:23930026

Maternal thyroid function in women undergoing controlled ovarian hyperstimulation during in-vitro fertilization and its relation to reproductive outcome.

PubMed

Abdul Karim, Abdul K; Azrai Abu, Muhammad; Chelliah, Buvanes; Mohd Razi, Zainul R; Omar, Mohd H; Othman, Hanita; Man, Zuraidah C

2017-10-01

We conducted a study to evaluate the changes in thyroid function during controlled ovarian hyperstimulation (COH) and its association with the outcome of assisted reproductive technique (ART). This is a prospective cohort study done in University Hospital Fertility Clinic for one year duration. A total of 88 euthyroid women who underwent COH as part of planned in-vitro fertilization (IVF) were invited to participate in this study. Serum thyroid function of each women will be monitored before stimulation (T1), day 10-13 of cycle (T2), during oocyte retrieval (T3), one week following embryo transfer (T4), and at four weeks after embryo transfer (T5). Reproductive outcome of IVF will be observed and documented. Nine women had ongoing singleton pregnancy, seven suffered from miscarriage, while the rest had implantation failure. Serum thyroid-stimulating hormone (TSH) and free thyroxine (fT4) increased throughout stimulation, peaking at 32-36 hours after hCG administration compared to baseline (1.250 vs. 1.740 mIU/L and 13.94 vs. 15.25 pmol/L). It remains elevated until one week following embryo transfer. The increment of serum TSH exceeded the upper limit, acceptable for first trimester (<1.60 mIU/L). However, the evolution of serum TSH and fT4 did not significantly differ with pregnancy outcome. In euthyroid women, thyroid function changed significantly during COH, but these changes were not different between the three reproductive outcomes. Thus, we do not suggest continuous thyroid function monitoring during COH.

The reproductive outcome of female patients with myotonic dystrophy type 1 (DM1) undergoing PGD is not affected by the size of the expanded CTG repeat tract

PubMed Central

Seneca, Sara; De Rademaeker, Marjan; Sermon, Karen; De Rycke, Martine; De Vos, Michel; Haentjens, Patrick; Devroey, Paul; Liebaers, Ingeborg

2010-01-01

Purpose This study aims to analyze the relationship between trinucleotide repeat length and reproductive outcome in a large cohort of DM1 patients undergoing ICSI and PGD. Methods Prospective cohort study. The effect of trinucleotide repeat length on reproductive outcome per patient was analyzed using bivariate analysis (T-test) and multivariate analysis using Kaplan-Meier and Cox regression analysis. Results Between 1995 and 2005, 205 cycles of ICSI and PGD were carried out for DM1 in 78 couples. The number of trinucleotide repeats does not have an influence on reproductive outcome when adjusted for age, BMI, basal FSH values, parity, infertility status and male or female affected. Cox regression analysis indicates that cumulative live birth rate is not influenced by the number of trinucleotide repeats. The only factor with a significant effect is age (p < 0.05). Conclusion There is no evidence of an effect of trinucleotide repeat length on reproductive outcome in patients undergoing ICSI and PGD. PMID:20221684

Influence of season of birth on growth and reproductive development of Brahman bulls.

PubMed

Tatman, Shawn R; Neuendorff, Don A; Wilson, Timothy W; Randel, Ronald D

2004-07-01

Seasonal effects on reproduction are more dramatic in Bos indicus than Bos taurus cattle. This experiment evaluated reproductive development of fall- (n=7) versus spring- (n = 10) born Brahman bulls to determine if season of birth affects reproductive development. Measurements of growth and reproductive development began after weaning and continued at bi-weekly intervals until each bull reached sexual maturity. Different stages of sexual development were classified according to characteristics of the ejaculate and included first sperm in the ejaculate, puberty (> 50 x 10(6) sperm/ejaculate), and sexual maturity (two ejaculates with > 500 = 10(6) sperm/ejaculate). Average daily increases in all measured traits were similar in fall- and spring-born bulls and there were no differences in age, body weight, scrotal circumference, or paired testis volume between groups at first sperm or puberty. However, fall-born bulls were older (P < 0.05) than spring-born bulls at sexual maturity (553 days versus 481 days, respectively) as the interval between puberty and sexual maturity was longer (P < 0.05) in fall- than in spring-born bulls (82 days versus 54 days, respectively). The prolonged interval between puberty and sexual maturity in fall-born calves coincided with a short photoperiod (winter) whereas the short interval between puberty and sexual maturity in spring-born calves coincided with a long photoperiod (summer). In conclusion, season of birth affected sexual development; photoperiod might be involved in regulating testicular function immediately after puberty in Brahman bulls.

Maternal condition and previous reproduction interact to affect offspring sex in a wild mammal.

PubMed

Douhard, Mathieu; Festa-Bianchet, Marco; Pelletier, Fanie

2016-08-01

Trivers and Willard proposed that offspring sex ratio should vary with maternal condition when condition, meant as maternal capacity to care, has different fitness consequences for sons and daughters. In polygynous and dimorphic species, mothers in good condition should preferentially produce sons, whereas mothers in poor condition should produce more daughters. Despite its logical appeal, support for this hypothesis has been inconsistent. Sex-ratio variation may be influenced by additional factors, such as environmental conditions and previous reproduction, which are often ignored in empirical studies. We analysed 39 years of data on bighorn sheep (Ovis canadensis) that fit all the assumptions of the Trivers-Willard hypothesis. Production of sons increased with maternal condition only for mothers that weaned a son the previous year. This relationship likely reflects a mother's ability to bear the higher reproductive costs of sons. The interaction between maternal condition and previous weaning success on the probability of producing a son was independent of the positive effect of paternal reproductive success. Maternal and paternal effects accounted for similar proportions of the variance in offspring sex. Maternal reproductive history should be considered in addition to current condition in studies of sex allocation. © 2016 The Author(s).

Integrating an automated activity monitor into an artificial insemination program and the associated risk factors affecting reproductive performance of dairy cows.

PubMed

Burnett, Tracy A; Madureira, Augusto M L; Silper, Bruna F; Fernandes, A C C; Cerri, Ronaldo L A

2017-06-01

The aim of this study was to compare 2 reproductive programs for the management of first postpartum artificial insemination (AI) based on activity monitors and timed AI, as well as to determine the effect of health-related factors on detection and expression of estrus. Lactating Holstein cows (n = 918) from 2 commercial farms were enrolled. Estrous cycles of all cows were presynchronized with 2 injections of PGF 2α administered 2 wk apart. Treatments were (1) first insemination performed by timed AI (TAI) and (2) first insemination based upon the detection of estrus by activity monitors (ACT; Heatime, SCR Engineering, Netanya, Israel) after the presynchronization, whereas cows not inseminated by the detection of estrus were enrolled in the Ovsynch protocol. Body condition score (BCS; scale 1 to 5), hock score (scale: 1 to 4), gait score (scale: 1 to 4), and corpus luteum presence detected by ovarian ultrasonography were recorded twice during the presynchronization. On the ACT treatment, 50.5% of cows were inseminated based on detected estrus, whereas 83.2% of the cows on the TAI treatment were inseminated appropriately after the timed AI protocol. Pregnancy per AI did not differ by treatment (30.8 vs. 33.5% for ACT and TAI, respectively). Success of pregnancy was affected by parity, cyclicity, BCS, milk production, and a tendency for leg health. In addition, treatment × cyclicity and treatment × parity interactions were found to affect pregnancy success, where anovulatory cows and older cows had compromised pregnancy outcomes on the ACT treatment but not on the TAI treatment. Factors affecting pregnancy outcomes varied among farms. Hazard of pregnancy by 300 DIM was affected by farm, parity, BCS, a treatment × cyclicity interaction, and a tendency for an interaction between leg health and farm. Detection of estrus was affected by farm, parity, cyclicity, and leg health, but not BCS or milk production. Expression of estrus was compromised in anovular and older

Photoperiod history differentially impacts reproduction and immune function in adult Siberian hamsters.

PubMed

Prendergast, Brian J; Pyter, Leah M

2009-12-01

Seasonal changes in numerous aspects of mammalian immune function arise as a result of the annual variation in environmental day length (photoperiod), but it is not known if absolute photoperiod or relative change in photoperiod drives these changes. This experiment tested the hypothesis that an individual's history of exposure to day length determines immune responses to ambiguous, intermediate-duration day lengths. Immunological (blood leukocytes, delayed-type hypersensitivity reactions [DTH]), reproductive, and adrenocortical responses were assessed in adult Siberian hamsters (Phodopus sungorus) that had been raised initially in categorically long (15-h light/day; 15L) or short (9L) photoperiods and were subsequently transferred to 1 of 7 cardinal experimental photoperiods between 9L and 15L, inclusive. Initial photoperiod history interacted with contemporary experimental photoperiods to determine reproductive responses: 11L, 12L, and 13L caused gonadal regression in hamsters previously exposed to 15L, but elicited growth in hamsters previously in 9L. In hamsters with a 15L photoperiod history, photoperiods < or = 11L elicited sustained enhancement of DTH responses, whereas in hamsters with a 9L photoperiod history, DTH responses were largely unaffected by increases in day length. Enhancement and suppression of blood leukocyte concentrations occurred at 13L in hamsters with photoperiod histories of 15L and 9L, respectively; however, prior exposure to 9L imparted marked hysteresis effects, which suppressed baseline leukocyte concentrations. Cortisol concentrations were only enhanced in 15L hamsters transferred to 9L and, in common with DTH, were unaffected by photoperiod treatments in hamsters with a 9L photoperiod history. Photoperiod history acquired in adulthood impacts immune responses to photoperiod, but manifests in a markedly dissimilar fashion as compared to the reproductive system. Prior photoperiod exposure has an enduring impact on the ability of the

Two-generation reproductive toxicity study of tributyltin chloride in female rats.

PubMed

Ogata, R; Omura, M; Shimasaki, Y; Kubo, K; Oshima, Y; Aou, S; Inoue, N

2001-05-25

A two-generation reproductive toxicity study of the effects of tributyltin chloride (TBTCl) was conducted in female rats using dietary concentrations of 5, 25, and 125 ppm TBTCl. Reproductive outcomes of dams (number and body weight of pups and the percentage of live pups) and the growth of female pups (the day of eye opening and body weight gain) were significantly decreased in the 125 ppm TBTCl group. A delay in vaginal opening and impaired estrous cyclicity were also observed in the 125 ppm TBTCl group. However, an increase in anogenital distance was found in all TBTCl groups on postnatal d 1. A dose-effect relationship was observed in TBTCl-induced changes in anogenital distance. These results indicate that the whole-life exposure to TBTCl affects the sexual development and reproductive function of female rats. In addition, the TBTCl-induced increase in anogenital distance seems to suggest it may exert a masculinizing effect on female neonates. However, the concentrations of TBTCl used in this study are not environmentally relevant.

Reproductive toxicologic evaluations of Bulbine natalensis Baker stem extract in albino rats.

PubMed

Yakubu, M T; Afolayan, A J

2009-08-01

The effects of oral administration of aqueous extract of Bulbine natalensis Baker stem at daily doses of 25, 50, and 100mg/kg body weight on the reproductive function of Wistar rats were evaluated. The indices of mating and fertility success as well as quantal frequency increased after 7 days of treatment in all the dose groups except the 100mg/kg body weight group. The number of litters was not statistically different (P>0.05) from the control. Whereas the absolute weights of the epididymis, seminal vesicle, and prostate were not affected, that of the testes was significantly increased. The epididymal sperm count, motility, morphology, and viscosity were not different from the control after 7 days of treatment. The male rat serum testosterone, progesterone, luteinizing hormone, and follicle-stimulating hormone significantly increased in the 25 and 50mg/kg body weight groups, whereas the estradiol concentration decreased significantly at all the doses. The extract dose of 100mg/kg body weight decreased the serum testosterone and progesterone levels in male rats. The prolactin concentration was not affected by all the doses. All the indices of reproduction, maternal, embryo/fetotoxic, teratogenic, and reproductive hormones in the female rats were not statistically different from that of their control except the resorption index, which increased at the dose of 100mg/kg body weight of the extract. Histologic examination of the cross section of rat testes that received the extract at all the doses investigated revealed well-preserved seminiferous tubules with normal amount of stroma, normal population of spermatogenic and supporting cells, as well as normal spermatocytes within the lumen. The results revealed that the aqueous extract of Bulbine natalensis stem at doses of 25 and 50mg/kg body weight enhanced the success rate of mating and fertility due to increased libido as well as the levels of reproductive hormones in male rats. The absence of alterations in the

Corticosterone manipulation reveals differences in hierarchical organization of multidimensional reproductive trade-offs in r-strategist and K-strategist females.

PubMed

Lancaster, L T; Hazard, L C; Clobert, J; Sinervo, B R

2008-03-01

Life history trade-offs are often hierarchical with decisions at one level affecting lower level trade-offs. We investigated trade-off structure in female side-blotched lizards (Uta stansburiana), which exhibit two evolved strategies: yellow-throated females are K-strategists and orange-throated are r-strategists. Corticosterone treatment was predicted to differentially organize these females' reproductive decisions. Corticosterone-treated yellow females suppressed reproduction but survived well, and augmented egg mass without decreasing clutch size. Conversely, corticosterone enhanced mortality and reproductive rates in orange females, and increased egg mass only after lengthy exposure. Corticosterone did not affect post-laying condition, suggesting that corticosterone increased egg mass through enhanced energy acquisition (income breeding). Corticosterone enhanced survival of lightweight females, but decreased survival of heavy females, introducing a foraging vs. predation trade-off. We conclude that rather than being a direct, functional relationship, observed trade-offs between offspring size and number represent evolved differences in hierarchical organization of multidimensional trade-offs, particularly in response to stress.

Updates in Reproduction Coming from the Endocannabinoid System

PubMed Central

Bradshaw, Heather B.

2014-01-01

The endocannabinoid system (ECS) is an evolutionarily conserved master system deeply involved in the central and local control of reproductive functions in both sexes. The tone of these lipid mediators—deeply modulated by the activity of biosynthetic and hydrolyzing machineries—regulates reproductive functions from gonadotropin discharge and steroid biosynthesis to the formation of high quality gametes and successful pregnancy. This review provides an overview on ECS and reproduction and focuses on the insights in the regulation of endocannabinoid production by steroids, in the regulation of male reproductive activity, and in placentation and parturition. Taken all together, evidences emerge that the activity of the ECS is crucial for procreation and may represent a target for the therapeutic exploitation of infertility. PMID:24550985

Biphasic effect of Syzygium aromaticum flower bud on reproductive physiology of male mice.

PubMed

Mishra, R K; Singh, S K

2016-11-01

The flower buds of Syzygium aromaticum (clove) have been used for the treatment of male sexual disorders in indigenous medicines of Indian subcontinent. Therefore to evaluate the efficacy of Syzygium aromaticum on the male reproductive health, chronic oral exposure of aqueous extract of flower buds of Syzygium in three doses (15 mg, 30 mg and 60 mg kg -1 BW) were studied for a single spermatogenic cycle (35 days) in Parkes (P) strain mice. Lower dose (15 mg) of Syzygium aromaticum flower buds increased serum testosterone level and testicular hydroxysteroid dehydrogenase (HSD) activities and improved sperm motility, sperm morphology, secretory activity of epididymis and seminal vesicle, and number of litters per female. On the other hand, higher doses (30 and 60 mg) of the treatment adversely affected above parameters. Further, higher doses of the extract also had adverse effects on daily sperm production, 1C cell population and on histology of testis. In conclusion, Syzygium aromaticum flower buds extract exhibits biphasic effect on reproductive physiology of male mice. Lower dose of Syzygium aromaticum flower bud extract is androgenic in nature and may have a viable future as an indigenous sexual rejuvenator, while higher doses adversely affected functional physiology of reproductive organs. © 2016 Blackwell Verlag GmbH.

Age-related changes in somatic condition and reproduction in the Eurasian beaver: Resource history influences onset of reproductive senescence

PubMed Central

Newman, Chris; Macdonald, David W.

2017-01-01

Using 15 years of data from a stable population of wild Eurasian beavers (Castor fiber), we examine how annual and lifetime access to food resources affect individual age-related changes in reproduction and somatic condition. We found an age-related decline in annual maternal reproductive output, after a peak at age 5–6. Rainfall, an established negative proxy of annual resource availability for beavers, was consistently associated with lower reproductive output for females of all ages. In contrast, breeding territory quality, as a measure of local resource history over reproductive lifetimes, caused differences in individual patterns of reproductive senescence; animals from lower quality territories senesced when younger. Litter size was unrelated to maternal age, although adult body weight increased with age. In terms of resource effects, in poorer years but not in better years, older mothers produced larger offspring than did younger mothers, giving support to the constraint theory. Overall, our findings exemplify state-dependent life-history strategies, supporting an effect of resources on reproductive senescence, where cumulative differences in resource access, and not just reproductive strategy, mediate long-term reproductive trade-offs, consistent with the disposable soma and reproductive restraint theories. We propose that flexible life-history schedules could play a role in the dynamics of populations exhibiting reproductive skew, with earlier breeding opportunities leading to an earlier senescence schedule through resource dependent mechanisms. PMID:29206840

Experimental defoliation affects male but not female reproductive performance of the tropical monoecious plant Croton suberosus (Euphorbiaceae).

PubMed

Narbona, Eduardo; Dirzo, Rodolfo

2010-08-01

Monoecious plants have the capacity to allocate resources separately to male and female functions more easily than hermaphrodites. This can be advantageous against environmental stresses such as leaf herbivory. However, studies showing effects of herbivory on male and female functions and on the interaction with the plant's pollinators are limited, particularly in tropical plants. Here, the effects of experimental defoliation were examined in the monoecious shrub Croton suberosus (Euphorbiaceae), a wasp-pollinated species from a Mexican tropical dry forest. Three defoliation treatments were applied: 0 % (control), 25 % (low) or 75 % (high) of plant leaf area removed. Vegetative (production of new leaves) and reproductive (pistillate and staminate flower production, pollen viability, nectar production, fruit set, and seed set) performance variables, and the abundance and activity of floral visitors were examined. Defoliated plants overcompensated for tissue loss by producing more new leaves than control plants. Production of staminate flowers gradually decreased with increasing defoliation and the floral sex ratio (staminate : pistillate flowers) was drastically reduced in high-defoliation plants. In contrast, female reproductive performance (pistillate flower production, fruit set and seed set) and pollinator visitation and abundance were not impacted by defoliation. The asymmetrical effects of defoliation on male and female traits of C. suberosus may be due to the temporal and spatial flexibility in the allocation of resources deployed by monoecious plants. We posit that this helps to maintain the plant's pollination success in the face of leaf herbivory stress.

Reproductive hacking. A male seminal protein acts through intact reproductive pathways in female Drosophila.

PubMed

Rubinstein, C Dustin; Wolfner, Mariana F

2014-01-01

Seminal proteins are critical for reproductive success in all animals that have been studied. Although seminal proteins have been identified in many taxa, and female reproductive responses to receipt of these proteins have been documented in several, little is understood about the mechanisms by which seminal proteins affect female reproductive physiology. To explore this topic, we investigated how a Drosophila seminal protein, ovulin, increases ovulation rate in mated females. Ovulation is a relatively simple physiological process, with known female regulators: previous studies have shown that ovulation rate is promoted by the neuromodulator octopamine (OA) in D. melanogaster and other insects. We found that ovulin stimulates ovulation by increasing OA signaling in the female. This finding supports a model in which a male seminal protein acts through "hacking" a well-conserved, regulatory system females use to adjust reproductive output, rather than acting downstream of female mechanisms of control or in parallel pathways altogether. We also discuss similarities between 2 forms of intersexual control of behavior through chemical communication: seminal proteins and pheromones.

Influence of oil-related environmental pollutants on female reproduction.

PubMed

Sirotkin, Alexander V; Harrath, Abdul Halim

2017-08-01

The petroleum low-weight aromatic hydrocarbons benzene, toluene, ethylbenzene, m/p-xylene, and o-xylene, also known as BTEX, are among the most common hazardous sources of environmental contamination. This paper reviews the available data concerning the effects of BTEX on different aspects of female reproduction, including the fecundity, ovaries, central nervous system (CNS), oocytes, embryos, oviducts, cytogenetics of somatic and generative cells, intracellular signaling systems, and hypothalamic, pituitary and peripheral reproductive hormones. Analysis of the available literature demonstrates that BTEX can exert negative effects on various female reproductive sites, including the CNS-pituitary-ovarian axis, their signaling molecules and receptors, ovarian follicles, corpora lutea, oocytes, embryos, oviducts, ovarian cycles, fertility, and the viability of offspring. These effects could be due to the ability of BTEX to destroy chromosomes, to affect cell metabolism, including the accumulation of free radicals, and to affect the release of hormonal regulators of reproductive processes and intracellular protein kinases. Copyright © 2017 Elsevier Inc. All rights reserved.

Perspectives on improvement of reproduction in cattle during heat stress in a future Japan.

PubMed

Kadokawa, Hiroya; Sakatani, Miki; Hansen, Peter J

2012-06-01

Heat stress (HS) causes hyperthermia, and at its most severe form, can lead to death. More commonly, HS reduces feed intake, milk yield, growth rate and reproductive function in many mammals and birds, including the important cattle breeds in Japan. Rectal temperatures greater than 39.0°C and respiration rates greater than 60/min indicate cows are undergoing HS sufficient to affect milk yield and fertility. HS compromises oocyte quality and embryonic development, reduces expression of estrus and changes secretion of several reproductive hormones. One of the most effective ways to reduce the magnitude of HS is embryo transfer, which bypasses the inhibitory effects of HS on the oocyte and early embryo. It may also be possible to select for genetic resistance to HS. Cooling can also improve reproductive performance in cows and heifers, and probably, the most effective cooling systems currently in use are those that couple evaporative cooling with tunnel ventilation or cross ventilation. Its effect on improving reproductive performance in Japan remains to be evaluated. © 2012 The Authors. Animal Science Journal © 2012 Japanese Society of Animal Science.

Reproductive cessation and post-reproductive lifespan in Asian elephants and pre-industrial humans

PubMed Central

2014-01-01

decline in fertility generally parallels declines in survivorship in contrast to humans with a decoupling of senescence in somatic and reproductive functions. Conclusions Our results show that the reproductive and survival patterns of Asian elephants differ from other long-lived animals exhibiting menopause, such as humans, and extreme longevity alone does not promote the evolution of menopause or post-reproductive lifespan, adding weight to the unusual kin-selected benefits suggested to favour such traits in humans and killer whales. PMID:25183990

Immunology and human reproduction.

PubMed

Alecsandru, Diana; García-Velasco, Juan Antonio

2015-06-01

The immune system's role in recurrent reproductive failure is a controversial issue in assisted reproduction. New insight about maternal tolerance in assisted reproduction has been reported and could explain some of the recurrent miscarriage and/or recurrent implantation failure related causes named until now as unknown. Most of the previous studies about immune system implication in reproduction were focused on finding markers on peripheral blood. Maternal tolerance begins at the uterine level, so successful adaptation to the fetus happens after a complicated process. Insufficient invasion of the uterine lining by invading extravillous trophoblast is the primary defect in pregnancy disorders such as recurrent miscarriage, and this process is regulated by interaction between maternal killer immunoglobulin-like receptors (KIRs) expressed by the uterine natural killer cells and their ligand human leukocyte antigen (HLA)-C expressed by extravillous trophoblast. Pregnancies are an increased risk of disorders in mothers with KIR AA when the fetus has paternal HLA-C2. Recently, it has been reported that the expression of more than one paternal HLA-C by extravillous trophoblast in assisted reproduction may affect placentation in mothers with KIR AA. The review provides insight about the immune tolerance process. These insights could have an impact on the selection of single embryo transfer and/or oocyte/sperm donor according to HLA-C in patients with recurrent miscarriage or recurrent implantation failure and a KIR AA haplotype.

Reproduction Alters Hydration State but Does Not Impact the Positive Effects of Dehydration on Innate Immune Function in Children's Pythons (Antaresia childreni).

PubMed

Brusch, George A; Billy, Gopal; Blattman, Joseph N; DeNardo, Dale F

Resource availability can impact immune function, with the majority of studies of such influences focusing on the allocation of energy investment into immune versus other physiological functions. When energy is a limited resource, performance trade-offs can result, compromising immunity. Dehydration is also considered a physiological challenge resulting from the limitation of a vital resource, yet previous research has found a positive relationship between dehydration and innate immune performance. However, these studies did not examine the effects of dehydration on immunity when there was another concurrent, substantial physiological challenge. Thus, we examined the impact of reproduction and water deprivation, individually and in combination, on immune performance in Children's pythons (Antaresia childreni). We collected blood samples from free-ranging A. childreni to evaluate osmolality and innate immune function (lysis, agglutination, bacterial growth inhibition) during the austral dry season, when water availability is limited and this species is typically reproducing. To examine how reproduction and water imbalance, both separately and combined, impact immune function, we used a laboratory-based 2 × 2 experiment. Our results demonstrate that A. childreni experience significant dehydration during the dry season and that, overall, osmolality, regardless of the underlying cause (seasonal rainfall, water deprivation, or reproduction), is positively correlated with increased innate immune performance.

Molecular regulation and role of angiogenesis in reproduction.

PubMed

Rizov, Momchil; Andreeva, Petya; Dimova, Ivanka

2017-04-01

Angiogenesis is an essential process for proper functioning of the female reproductive system and for successful pregnancy realization. The multitude of factors required for physiological angiogenesis and the complexity of regulation of their temporal-spatial activities contribute to aberrations in human fertilization and pregnancy outcomes. In this study, we reviewed the current knowledge of the temporal expression patterns, functions, and regulatory mechanisms of angiogenic factors during foliculogenesis, early implantation/placentation and embryo development, as well as recurrent spontaneous abortions. Angiogenic factors including vascular endothelial growth factors and angiopoietins have documented roles in the development of primordial follicles into mature antral follicles. They also participate in decidualization, which is accompanied by the creation of an extensive network of vessels in the stromal bed that support the growth of the embryo and the placenta, and maintain early pregnancy. During placentation angiogenic and angiomodulatory cytokines, T and B lymphocytes and macrophages affect angiogenesis in a context-dependent manner. Defects in angiogenesis at the maternal-fetal interface contribute to miscarriage in humans. The establishment of more polymorphisms in the genes involved in angiogenesis/vasculogenesis, and their pathological phenotype and expression could give opportunities for prediction, creating a therapeutic strategy, and treatment of diseases related to female reproductive health and problematic conception. Copyright © 2017. Published by Elsevier B.V.

Natural selection and the evolution of reproductive effort.

PubMed

Hirshfield, M F; Tinkle, D W

1975-06-01

Reproductive effort is defined as that proportion of the total energy budget of an organism that is devoted to reproductive processes. Reproductive effort at a given age within a species will be selected to maximize reproductive value at that age. Reproductive effort is not directly affected by changes in juvenile survivorship, nor necessarily reduced by an increase in adult survivorship. Selection for high levels of reproductive effort should occur when extrinsic adult mortality is high, in environments with constant juvenile survivorship, and in good years for juvenile survivorship in a variable environment, provided that the quality of the year is predictable by adults. Data necessary to measure reproductive effort and to understand how selection results in different levels of effort between individuals and species are discussed. We make several predictions about the effect of increased resource availability on reproductive effort. The empirical bases for testing these predictions are presently inadequate, and we consider data on energy budgets of organisms in nature to be essential for such test. We also conclude that variance in life table parameters must be known in detail to understand the selective bases of levels of reproductive effort.

Deconstructing mammalian reproduction: using knockouts to define fertility pathways.

PubMed

Roy, Angshumoy; Matzuk, Martin M

2006-02-01

Reproduction is the sine qua non for the propagation of species and continuation of life. It is a complex biological process that is regulated by multiple factors during the reproductive life of an organism. Over the past decade, the molecular mechanisms regulating reproduction in mammals have been rapidly unraveled by the study of a vast number of mouse gene knockouts with impaired fertility. The use of reverse genetics to generate null mutants in mice through targeted disruption of specific genes has enabled researchers to identify essential regulators of spermatogenesis and oogenesis in vivo and model human disorders affecting reproduction. This review focuses on the merits, utility, and the variations of the knockout technology in studies of reproduction in mammals.

High Temperatures Result in Smaller Nurseries which Lower Reproduction of Pollinators and Parasites in a Brood Site Pollination Mutualism

PubMed Central

Krishnan, Anusha; Pramanik, Gautam Kumar; Revadi, Santosh V.; Venkateswaran, Vignesh; Borges, Renee M.

2014-01-01

In a nursery pollination mutualism, we asked whether environmental factors affected reproduction of mutualistic pollinators, non-mutualistic parasites and seed production via seasonal changes in plant traits such as inflorescence size and within-tree reproductive phenology. We examined seasonal variation in reproduction in Ficus racemosa community members that utilise enclosed inflorescences called syconia as nurseries. Temperature, relative humidity and rainfall defined four seasons: winter; hot days, cold nights; summer and wet seasons. Syconium volumes were highest in winter and lowest in summer, and affected syconium contents positively across all seasons. Greater transpiration from the nurseries was possibly responsible for smaller syconia in summer. The 3–5°C increase in mean temperatures between the cooler seasons and summer reduced fig wasp reproduction and increased seed production nearly two-fold. Yet, seed and pollinator progeny production were never negatively related in any season confirming the mutualistic fig–pollinator association across seasons. Non-pollinator parasites affected seed production negatively in some seasons, but had a surprisingly positive relationship with pollinators in most seasons. While within-tree reproductive phenology did not vary across seasons, its effect on syconium inhabitants varied with season. In all seasons, within-tree reproductive asynchrony affected parasite reproduction negatively, whereas it had a positive effect on pollinator reproduction in winter and a negative effect in summer. Seasonally variable syconium volumes probably caused the differential effect of within-tree reproductive phenology on pollinator reproduction. Within-tree reproductive asynchrony itself was positively affected by intra-tree variation in syconium contents and volume, creating a unique feedback loop which varied across seasons. Therefore, nursery size affected fig wasp reproduction, seed production and within-tree reproductive

Female reproductive cycles of wild female felids.

PubMed

Brown, Janine L

2011-04-01

Many felid species are endangered because of destructive human activities. As a result, zoos are being tasked with sustaining genetically healthy populations in case of catastrophic extinctions. Unfortunately, with the exception of a few species, most felids do not reproduce well in captivity. The ability to track reproductive activity via hormones is key to developing successful ex situ breeding programs. Through the development of noninvasive fecal hormone monitoring techniques, a high degree of variability in estrous cycle characteristics has been found to exist across the taxon, including the type of ovulation. For example, although all felids have induced ovulations, the occurrence of spontaneous ovulations varies across species, and even between individuals within a species. Clouded leopards, fishing cats and margays frequently have spontaneous ovulations, whereas these are rarely observed in the cheetah, tigrina and ocelot. There are marked species differences in the impact of season on reproductive function, with some being exquisitely sensitive to photoperiod (e.g., Pallas' cat), some moderately affected (tiger, clouded leopard, snow leopard), and others that are not influenced at all (e.g., ocelot, tigrina, margay, lion, leopard, fishing cat). One of the greatest challenges remaining is overcoming the problems associated with highly variable ovarian responses to ovulation induction therapies used with assisted reproductive procedures, like artificial insemination (AI). Success is relatively high in the cheetah and ocelot, but few pregnancies have resulted after AI in clouded leopard, fishing cat and tiger. Current knowledge of the reproductive physiology of nondomestic felids, including aspects of the anatomy, behavior and ovarian cycles will be presented, and how the rapidly growing endocrine database is aiding ex situ management efforts. Published by Elsevier B.V.

Does alcohol have any effect on male reproductive function? A review of literature.

PubMed

La Vignera, Sandro; Condorelli, Rosita A; Balercia, Giancarlo; Vicari, Enzo; Calogero, Aldo E

2013-03-01

Although alcohol is widely used, its impact on the male reproductive function is still controversial. Over the years, many studies have investigated the effects of alcohol consumption on sperm parameters and male infertility. This article reviews the main preclinical and clinical evidences. Studies conducted on the experimental animal have shown that a diet enriched with ethanol causes sperm parameter abnormalities, a number of alterations involving the reproductive tract inhibition, and reduced mouse oocyte in vitro fertilization rate. These effects were partly reversible upon discontinuation of alcohol consumption. Most of the studies evaluating the effects of alcohol in men have shown a negative impact on the sperm parameters. This has been reported to be associated with hypotestosteronemia and low-normal or elevated gonadotropin levels suggesting a combined central and testicular detrimental effect of alcohol. Nevertheless, alcohol consumption does not seem to have much effect on fertility either in in vitro fertilization programs or population-based studies. Finally, the genetic background and other concomitant, alcohol consumption-related conditions influence the degree of the testicular damage. In conclusion, alcohol consumption is associated with a deterioration of sperm parameters which may be partially reversible upon alcohol consumption discontinuation.

The ecology and evolutionary endocrinology of reproduction in the human female.

PubMed

Vitzthum, Virginia J

2009-01-01

Human reproductive ecology (HRE) is the study of the mechanisms that link variation in reproductive traits with variation in local habitats. Empirical and theoretical contributions from biological anthropology, physiology, and demography have established the foundation necessary for developing a comprehensive understanding, grounded in life history theory (LHT), of temporal, individual, and populational variation in women's reproductive functioning. LHT posits that natural selection leads to the evolution of mechanisms that tend to allocate resources to the competing demands of growth, reproduction, and survival such that fitness is locally maximized. (That is, among alternative allocation patterns exhibited in a population, those having the highest inclusive fitness will become more common over generational time.) Hence, strategic modulation of reproductive effort is potentially adaptive because investment in a new conception may risk one's own survival, future reproductive opportunities, and/or current offspring survival. The hypothalamic-pituitary-ovarian (HPO) axis is the principal neuroendocrine pathway by which the human female modulates reproductive functioning according to the changing conditions in her habitat. Adjustments of reproductive investment in a potential conception are manifested in temporal and individual variation in ovarian cycle length, ovulation, hormone levels, and the probability of conception. Understanding the extent and causes of adaptive and non-adaptive variation in ovarian functioning is fundamental to ascertaining the proximate and remote determinants of human reproductive patterns. In this review I consider what is known and what still needs to be learned of the ecology of women's reproductive biology, beginning with a discussion of the principal explanatory frameworks in HRE and the biometry of ovarian functioning. Turning next to empirical studies, it is evident that marked variation between cycles, women, and populations is the

Indirect genetic effects and sexual conflicts: Partner genotype influences multiple morphological and behavioral reproductive traits in a flatworm.

PubMed

Marie-Orleach, Lucas; Vogt-Burri, Nadja; Mouginot, Pierick; Schlatter, Aline; Vizoso, Dita B; Bailey, Nathan W; Schärer, Lukas

2017-05-01

The expression of an individual's phenotypic traits can be influenced by genes expressed in its social partners. Theoretical models predict that such indirect genetic effects (IGEs) on reproductive traits should play an important role in determining the evolutionary outcome of sexual conflict. However, empirical tests of (i) whether reproductive IGEs exist, (ii) how they vary among genotypes, and (iii) whether they are uniform for different types of reproductive traits are largely lacking. We addressed this in a series of experiments in the simultaneously hermaphroditic flatworm Macrostomum lignano. We found strong evidence for IGEs on both morphological and behavioral reproductive traits. Partner genotype had a significant impact on the testis size of focal individuals-varying up to 2.4-fold-suggesting that IGEs could mediate sexual conflicts that target the male sex function. We also found that time to first copulation was affected by a genotype × genotype interaction between mating partners, and that partner genotype affected the propensity to copulate and perform the postcopulatory suck behavior, which may mediate conflicts over the fate of received ejaculate components. These findings provide clear empirical evidence for IGEs on multiple behavioral and morphological reproductive traits, which suggests that the evolutionary dynamics of these traits could be altered by genes contained in the social environment. © 2017 The Author(s). Evolution © 2017 The Society for the Study of Evolution.

Functional Multijoint Position Reproduction Acuity in Overhead-Throwing Athletes

PubMed Central

Tripp, Brady L; Uhl, Timothy L; Mattacola, Carl G; Srinivasan, Cidambi; Shapiro, Robert

2006-01-01

Context: Baseball players rely on the sensorimotor system to uphold the balance between upper extremity stability and mobility while maintaining athletic performance. However, few researchers have studied functional multijoint measures of sensorimotor acuity in overhead-throwing athletes. Objective: To compare sensorimotor acuity between 2 high-demand functional positions and among planes of motion within individual joints and to describe a novel method of measuring sensorimotor function. Design: Single-session, repeated-measures design. Setting: University musculoskeletal research laboratory. Patients or Other Participants: Twenty-one National Collegiate Athletic Association Division I baseball players (age = 20.8 ± 1.5 years, height = 181.3 ± 5.1 cm, mass = 87.8 ± 9.1 kg) with no history of upper extremity injury or central nervous system disorder. Main Outcome Measure(s): We measured active multijoint position reproduction acuity in multiple planes using an electromagnetic tracking device. Subjects reproduced 2 positions: arm cock and ball release. We calculated absolute and variable error for individual motions at the scapulothoracic, glenohumeral, elbow, and wrist joints and calculated overall joint acuity with 3-dimensional variable error. Results: Acuity was significantly better in the arm-cock position compared with ball release at the scapulothoracic and glenohumeral joints. We observed significant differences among planes of motion within the scapulothoracic and glenohumeral joints at ball release. Scapulothoracic internal rotation and glenohumeral horizontal abduction and rotation displayed less acuity than other motions. Conclusions: We established the reliability of a functional measure of upper extremity sensorimotor system acuity in baseball players. Using this technique, we observed differences in acuity between 2 test positions and among planes of motion within the glenohumeral and scapulothoracic joints. Clinicians may consider these

Co-administration of caffeine and caffeic acid alters some key enzymes linked with reproductive function in male rats.

PubMed

Akomolafe, S F; Akinyemi, A J; Oboh, G; Oyeleye, S I; Ajayi, O B; Omonisi, A E; Owolabi, F L; Atoyebi, D A; Ige, F O; Atoki, V A

2018-03-01

This study assessed the effects of caffeine combined with caffeic acid on some biomarkers of male reproductive function using normal albino Wistar rats. Rats were divided into four groups (n = 6) and treated for seven successive days; group 1 represents the control rats; group 2 rats were treated with 50 mg/kg body weight (BW) of caffeine only; group 3 rats were treated with 50 mg/kg BW of caffeic acid, while the rats in group 4 were cotreated with an equal combination of caffeine and caffeic acid. The results revealed significant increase in reproductive hormone, testicular and epididymal nitric oxide levels of the rats. Moreover, decreased oxidative stress in the testes and epididymides of the treated rats was evidenced by significant increase in total and nonprotein thiol levels, catalase and superoxide dismutase activities. Similarly, decreased testicular cholesterol level with concomitant elevation in testicular steroidogenic enzyme activities, glycogen and zinc levels were observed in the treated rats. No morphological changes were observed as revealed by the photomicrographs from light microscopy in treated rats. Nevertheless, the combination therapy exhibited additive/synergistic effect on these biochemical indices than when they were administered singly. This study suggests the combination therapy of caffeine and caffeic acid at the dose tested for improving male reproductive function. © 2017 Blackwell Verlag GmbH.

Leptin and its potential interest in assisted reproduction cycles.

PubMed

Catteau, A; Caillon, H; Barrière, P; Denis, M G; Masson, D; Fréour, T

2016-04-01

Leptin, an adipose hormone, has been shown to control energy homeostasis and food intake, and exert many actions on female reproductive function. Consequently, this adipokine is a pivotal factor in studies conducted on animal models and humans to decipher the mechanisms behind the infertility often observed in obese women. A systematic PubMed search was conducted on all articles, published up to January 2015 and related to leptin and its actions on energy balance and reproduction, using the following key words: leptin, reproduction, infertility, IVF and controlled ovarian stimulation. The available literature was reviewed in order to provide an overview of the current knowledge on the physiological roles of leptin, its involvement in female reproductive function and its potential interest as a prognostic marker in IVF cycles. Animal and human studies show that leptin communicates nutritional status to the central nervous system and emerging evidence has demonstrated that leptin is involved in the control of reproductive functions by acting both directly on the ovaries and indirectly on the central nervous system. With respect to the clinical use of leptin as a biomarker in IVF cycles, a systematic review of the literature suggested its potential interest as a predictor of IVF outcome, as high serum and/or follicular fluid leptin concentrations have correlated negatively with cycle outcome. However, these preliminary results remain to be confirmed. Leptin regulates energy balance and female reproductive function, mainly through its action on hypothalamic-pituitary-ovarian function, whose molecular and cellular aspects are progressively being deciphered. Preliminary studies evaluating leptin as a biomarker in human IVF seem promising but need further confirmation. © The Author 2015. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Rethinking reproductive "tourism" as reproductive "exile".

PubMed

Inhorn, Marcia C; Patrizio, Pasquale

2009-09-01

Whereas reproductive "tourism" implies leisure travel, reproductive "exile" bespeaks the numerous difficulties and constraints faced by infertile patients who are "forced" to travel globally for assisted reproduction. Given this reality, it is time to rethink the language of "reproductive tourism," replacing it with more accurate and patient-centered terms.

Effects of synthetic gestagens on fish reproduction.

PubMed

Zeilinger, Jana; Steger-Hartmann, Thomas; Maser, Edmund; Goller, Stephan; Vonk, Richardus; Länge, Reinhard

2009-12-01

Although it is well known that estrogenic steroidal hormones are able to affect the sexual development and reproduction of fish at low concentrations, no data on environmental effects of the class of progestogenic hormones are available yet. Synthetic gestagens (progestins) are a component in oral contraceptives. Upon their use, a fraction of the progestins will be excreted via urine into the aquatic environment. On the basis of their pharmacological action in mammals, it is supposed that fish reproduction is the most sensitive endpoint for the progestin treatment. In order to test this assumption, the effects of two progestins currently marketed in contraceptive formulations, levonorgestrel (LNG) and drospirenone (DRSP), were investigated in adult fathead minnows (Pimephales promelas) following an Organization for Economic Cooperation and Development 21-d fish reproduction screening assay draft protocol with additional end points. Levonorgestrel was tested at measured concentrations of 0.8, 3.3, and 29.6 ng/L, and DRSP at concentrations of 0.66, 6.5, and 70 microg/L. Both tested progestins caused an inhibition of reproduction. For LNG, this occurred at concentrations of >or=0.8 ng/L, no no-observed-effect concentration (NOEC) could be defined. Higher concentrations resulted in masculinization of females with de novo synthesis of nuptial tubercles. Drospirenone treatment, however, affected the reproductive success of fathead minnow at concentrations of 6.5 microg/L and higher with a clear dose-response relationship and a NOEC of 0.66 microg/L, which is above environmentally relevant concentrations.

Reproductive Efficiency of a Mediterranean Endemic Zooxanthellate Coral Decreases with Increasing Temperature along a Wide Latitudinal Gradient

PubMed Central

Airi, Valentina; Gizzi, Francesca; Falini, Giuseppe; Levy, Oren; Dubinsky, Zvy; Goffredo, Stefano

2014-01-01

Investments at the organismal level towards reproduction and growth are often used as indicators of health. Understanding how such energy allocation varies with environmental conditions may, therefore, aid in predicting possible responses to global climatic change in the near future. For example, variations in seawater temperature may alter the physiological functioning, behavior, reproductive output and demographic traits (e.g., productivity) of marine organisms, leading to shifts in the structure, spatial range, and abundance of populations. This study investigated variations in reproductive output associated with local seawater temperature along a wide latitudinal gradient on the western Italian coast, in the zooxanthellate Mediterranean coral, Balanophyllia europaea. Reproductive potential varied significantly among sites, where B. europaea individuals from the warmest site experienced loss of oocytes during gametogenesis. Most of the early oocytes from warmest sites did not reach maturity, possibly due to inhibition of metabolic processes at high temperatures, causing B. europaea to reabsorb the oocytes and utilize them as energy for other vital functions. In a progressively warming Mediterranean, the efficiency of the energy invested in reproduction could be considerably reduced in this species, thereby affecting vital processes. Given the projected increase in seawater temperature as a consequence of global climate change, the present study adds evidence to the threats posed by high temperatures to the survival of B. europaea in the next decades. PMID:24618568

microRNA in Human Reproduction.

PubMed

Eisenberg, Iris; Kotaja, Noora; Goldman-Wohl, Debra; Imbar, Tal

2015-01-01

microRNAs constitute a large family of approximately 21-nucleotide-long, noncoding RNAs. They emerged more than 20 years ago as key posttranscriptional regulators of gene expression. The regulatory role of these small RNA molecules has recently begun to be explored in the human reproductive system. microRNAs have been shown to play an important role in control of reproductive functions, especially in the processes of oocyte maturation, folliculogenesis, corpus luteum function, implantation, and early embryonic development. Knockout of Dicer, the cytoplasmic enzyme that cleaves the pre-miRNA to its mature form, results in postimplantation embryonic lethality in several animal models, attributing to these small RNA vital functions in reproduction and development. Another intriguing characteristic of microRNAs is their presence in body fluids in a remarkably stable form that is protected from endogenous RNase activity. In this chapter we will describe the current knowledge on microRNAs, specifically relating to human gonadal cells. We will focus on their role in the ovarian physiologic process and ovulation dysfunction, regulation of spermatogenesis and male fertility, and putative involvement in human normal and aberrant trophoblast differentiation and invasion through the process of placentation.

Pre- and Postnatal Nutritional Histories Influence Reproductive Maturation and Ovarian Function in the Rat

PubMed Central

Sloboda, Deborah M.; Howie, Graham J.; Pleasants, Anthony; Gluckman, Peter D.; Vickers, Mark H.

2009-01-01

Background While prepubertal nutritional influences appear to play a role in sexual maturation, there is a need to clarify the potential contributions of maternal and childhood influences in setting the tempo of reproductive maturation. In the present study we employed an established model of nutritional programming to evaluate the relative influences of prenatal and postnatal nutrition on growth and ovarian function in female offspring. Methods Pregnant Wistar rats were fed either a calorie-restricted diet, a high fat diet, or a control diet during pregnancy and/or lactation. Offspring then were fed either a control or a high fat diet from the time of weaning to adulthood. Pubertal age was monitored and blood samples collected in adulthood for endocrine analyses. Results We report that in the female rat, pubertal timing and subsequent ovarian function is influenced by the animal's nutritional status in utero, with both maternal caloric restriction and maternal high fat nutrition resulting in early pubertal onset. Depending on the offspring's nutritional history during the prenatal and lactational periods, subsequent nutrition and body weight gain did not further influence offspring reproductive tempo, which was dominated by the effect of prenatal nutrition. Whereas maternal calorie restriction leads to early pubertal onset, it also leads to a reduction in adult progesterone levels later in life. In contrast, we found that maternal high fat feeding which also induces early maturation in offspring was associated with elevated progesterone concentrations. Conclusions These observations are suggestive of two distinct developmental pathways leading to the acceleration of pubertal timing but with different consequences for ovarian function. We suggest different adaptive explanations for these pathways and for their relationship to altered metabolic homeostasis. PMID:19707592

Prolactin secretion patterns: basic mechanisms and clinical implications for reproduction.

PubMed

Egli, Marcel; Leeners, Brigitte; Kruger, Tillmann H C

2010-11-01

Prolactin (PRL) is one of the most versatile hormones in the mammalian body affecting reproductive, sexual, metabolic, immune, and other functions. It is therefore not surprising that the neural control of PRL secretion is complex, involving the coordinated actions of several hypothalamic nuclei. A plethora of experimental data exists on the hypothalamic control of hormone secretion under various physiological stimuli. There have been even mathematical models and computer studies published, which help to understand the complex hypothalamic-pituitary network. Nevertheless, the putative role of PRL for human reproduction still has to be clarified. Here, we review data on the underlying mechanisms controlling PRL secretion using both experimental and mathematical approaches. These investigations primarily focus on rhythmic secretion in rats during early pregnancy or pseudopregnancy, and they point to the important role of oxytocin as a crucial PRL-releasing factor. Recent data on human studies and their theoretical and clinical implications are reviewed as well. In particular, studies demonstrating a sustained PRL surge after sexual climax in males and females are presented, indicating possible implications for both sexual satiation and reproductive functions. Taking these data together, there is evidence for the hypothesis that the PRL surge induced by sexual activity, together with the altered PRL rhythmic pattern, is important for successful initialization of pregnancy not only in rodents but also possibly in humans. However, further investigations are needed to clarify such a role in humans.

Post-Disaster Reproductive Health Outcomes

PubMed Central

Zotti, Marianne E.; Williams, Amy M.; Robertson, McKaylee; Horney, Jennifer; Hsia, Jason

2015-01-01

We examined methodological issues in studies of disaster-related effects on reproductive health outcomes and fertility among women of reproductive age and infants in the United States (US). We conducted a systematic literature review of 1,635 articles and reports published in peer-reviewed journals or by the government from January 1981 through December 2010. We classified the studies using three exposure types: (1) physical exposure to toxicants; (2) psychological trauma; and (3) general exposure to disaster. Fifteen articles met our inclusion criteria concerning research focus and design. Overall studies pertained to eight different disasters, with most (n = 6) focused on the World Trade Center attack. Only one study examined pregnancy loss, i.e., occurrence of spontaneous abortions post-disaster. Most studies focused on associations between disaster and adverse birth outcomes, but two studies pertained only to post-disaster fertility while another two examined it in addition to adverse birth outcomes. In most studies disaster-affected populations were assumed to have experienced psychological trauma, but exposure to trauma was measured in only four studies. Furthermore, effects of both physical exposure to toxicants and psychological trauma on disaster-affected populations were examined in only one study. Effects on birth outcomes were not consistently demonstrated, and study methodologies varied widely. Even so, these studies suggest an association between disasters and reproductive health and highlight the need for further studies to clarify associations. We postulate that post-disaster surveillance among pregnant women could improve our understanding of effects of disaster on the reproductive health of US pregnant women. PMID:22752348

Dim artificial light at night affects mating, reproductive output, and reactive oxygen species in Drosophila melanogaster.

PubMed

McLay, Lucy Katherine; Nagarajan-Radha, Venkatesh; Green, Mark Philip; Jones, Therésa Melanie

2018-05-07

Humans are lighting the night-time environment with ever increasing extent and intensity, resulting in a variety of negative ecological effects in individuals and populations. Effects of light at night on reproductive fitness traits are demonstrated across taxa however, the mechanisms underlying these effects are largely untested. One possible mechanism is that light at night may result in perturbed reactive oxygen species (ROS) and oxidative stress levels. Here, we reared Drosophila melanogaster under either dim (10 lx) light or no light (0 lx) at night for three generations and then compared mating and lifetime oviposition patterns. In a second experiment, we explored whether exposure to light at night treatments resulted in variation in ROS levels in the heads and ovaries of six, 23- and 36-day-old females. We demonstrate that dim light at night affects mating and reproductive output: 10 lx flies courted for longer prior to mating, and female oviposition patterns differed to 0 lx females. ROS levels were lower in the ovaries but not heads, of 10 lx compared with 0 lx females. We suggest that reduced ROS levels may reflect changes in ovarian physiology and cell signaling, which may be related to the differences observed in oviposition patterns. Taken together, our results indicate negative consequences for invertebrates under more stressful, urban, lit conditions and further investigation into the mechanisms driving these changes is warranted to manage invertebrate communities in a brighter future. © 2018 Wiley Periodicals, Inc.

Doping with anabolic androgenic steroids (AAS): Adverse effects on non-reproductive organs and functions.

PubMed

Nieschlag, Eberhard; Vorona, Elena

2015-09-01

Since the 1970s anabolic androgenic steroids (AAS) have been abused at ever increasing rates in competitive athletics, in recreational sports and in bodybuilding. Exceedingly high doses are often consumed over long periods, in particular by bodybuilders, causing acute or chronic adverse side effects frequently complicated by additional polypharmacy. This review summarizes side effects on non-reproductive organs and functions; effects on male and female reproduction have been recently reviewed in a parallel paper. Among the most striking AAS side effects are increases in haematocrit and coagulation causing thromboembolism, intracardiac thrombosis and stroke as well as other cardiac disturbances including arrhythmias, cardiomyopathies and possibly sudden death. 17α-alkylated AAS are liver toxic leading to cholestasis, peliosis, adenomas and carcinomas. Hyperbilirubinaemia can cause cholemic nephrosis and kidney failure. AAS abuse may induce exaggerated self-confidence, reckless behavior, aggressiveness and psychotic symptoms. AAS withdrawal may be accompanied by depression and suicidal intentions. Since AAS abuse is not or only reluctantly admitted physicians should be aware of the multitude of serious side effects when confronted with unclear symptoms.

The vaginal microbiota, host defence and reproductive physiology

PubMed Central

Smith, Steven B

2016-01-01

Abstract The interaction between the human host and the vaginal microbiota is highly dynamic. Major changes in the vaginal physiology and microbiota over a woman's lifetime are largely shaped by transitional periods such as puberty, menopause and pregnancy, while daily fluctuations in microbial composition observed through culture‐independent studies are more likely to be the results of daily life activities and behaviours. The vaginal microbiota of reproductive‐aged women is largely made up of at least five different community state types. Four of these community state types are dominated by lactic‐acid producing Lactobacillus spp. while the fifth is commonly composed of anaerobes and strict anaerobes and is sometimes associated with vaginal symptoms. The production of lactic acid has been associated with contributing to the overall health of the vagina due to its direct and indirect effects on pathogens and host defence. Some species associated with non‐Lactobacillus vaginal microbiota may trigger immune responses as well as degrade the host mucosa, processes that ultimately increase susceptibility to infections and contribute to negative reproductive outcomes such as infertility and preterm birth. Further studies are needed to better understand the functional underpinnings of how the vaginal microbiota affect host physiology but also how host physiology affects the vaginal microbiota. Understanding this fine‐tuned interaction is key to maintaining women's reproductive health. PMID:27373840

Alcohol, drugs, caffeine, tobacco, and environmental contaminant exposure: reproductive health consequences and clinical implications.

PubMed

Sadeu, J C; Hughes, Claude L; Agarwal, Sanjay; Foster, Warren G

2010-08-01

Reproductive function and fertility are thought to be compromised by behaviors such as cigarette smoking, substance abuse, and alcohol consumption; however, the strength of these associations are uncertain. Furthermore, the reproductive system is thought to be under attack from exposure to environmental contaminants, particularly those chemicals shown to affect endocrine homeostasis. The relationship between exposure to environmental contaminants and adverse effects on human reproductive health are frequently debated in the scientific literature and these controversies have spread into the lay press drawing increased public and regulatory attention. Therefore, the objective of the present review was to critically evaluate the literature concerning the relationship between lifestyle exposures and adverse effects on fertility as well as examining the evidence for a role of environmental contaminants in the purported decline of semen quality and the pathophysiology of subfertility, polycystic ovarian syndrome, and endometriosis. The authors conclude that whereas cigarette smoking is strongly associated with adverse reproductive outcomes, high-level exposures to other lifestyle factors are only weakly linked with negative fertility impacts. Finally, there is no compelling evidence that environmental contaminants, at concentrations representative of the levels measured in contemporary biomonitoring studies, have any effect, positive or negative, on reproductive health in the general population. Further research using prospective study designs with robust sample sizes are needed to evaluate testable hypotheses that address the relationship between exposure and adverse reproductive health effects.

Sense and Nonsense in Metabolic Control of Reproduction

PubMed Central

Schneider, Jill E.; Klingerman, Candice M.; Abdulhay, Amir

2012-01-01

An exciting synergistic interaction occurs among researchers working at the interface of reproductive biology and energy homeostasis. Reproductive biologists benefit from the theories, experimental designs, and methodologies used by experts on energy homeostasis while they bring context and meaning to the study of energy homeostasis. There is a growing recognition that identification of candidate genes for obesity is little more than meaningless reductionism unless those genes and their expression are placed in a developmental, environmental, and evolutionary context. Reproductive biology provides this context because metabolic energy is the most important factor that controls reproductive success and gonadal hormones affect energy intake, storage, and expenditure. Reproductive hormone secretion changes during development, and reproductive success is key to evolutionary adaptation, the process that most likely molded the mechanisms that control energy balance. It is likely that by viewing energy intake, storage, and expenditure in the context of reproductive success, we will gain insight into human obesity, eating disorders, diabetes, and other pathologies related to fuel homeostasis. This review emphasizes the metabolic hypothesis: a sensory system monitors the availability of oxidizable metabolic fuels and orchestrates behavioral motivation to optimize reproductive success in environments where energy availability fluctuates or is unpredictable. PMID:22649413

Sense and nonsense in metabolic control of reproduction.

PubMed

Schneider, Jill E; Klingerman, Candice M; Abdulhay, Amir

2012-01-01

An exciting synergistic interaction occurs among researchers working at the interface of reproductive biology and energy homeostasis. Reproductive biologists benefit from the theories, experimental designs, and methodologies used by experts on energy homeostasis while they bring context and meaning to the study of energy homeostasis. There is a growing recognition that identification of candidate genes for obesity is little more than meaningless reductionism unless those genes and their expression are placed in a developmental, environmental, and evolutionary context. Reproductive biology provides this context because metabolic energy is the most important factor that controls reproductive success and gonadal hormones affect energy intake, storage, and expenditure. Reproductive hormone secretion changes during development, and reproductive success is key to evolutionary adaptation, the process that most likely molded the mechanisms that control energy balance. It is likely that by viewing energy intake, storage, and expenditure in the context of reproductive success, we will gain insight into human obesity, eating disorders, diabetes, and other pathologies related to fuel homeostasis. This review emphasizes the metabolic hypothesis: a sensory system monitors the availability of oxidizable metabolic fuels and orchestrates behavioral motivation to optimize reproductive success in environments where energy availability fluctuates or is unpredictable.

Time reproduction performance is associated with age and working memory in high-functioning youth with autism spectrum disorder.

PubMed

Brenner, Laurie A; Shih, Vivian H; Colich, Natalie L; Sugar, Catherine A; Bearden, Carrie E; Dapretto, Mirella

2015-02-01

Impaired temporal processing has historically been viewed as a hallmark feature of attention deficit hyperactivity disorder. Recent evidence suggests temporal processing deficits may also be characteristic of autism spectrum disorder (ASD). However, little is known about the factors that impact temporal processing in children with ASD. The purpose of this study was to assess the effects of co-morbid attention problems, working memory (WM), age, and their interactions, on time reproduction in youth with and without ASD. Twenty-seven high-functioning individuals with ASD and 25 demographically comparable typically developing individuals (ages 9-17; 85% male) were assessed on measures of time reproduction, auditory WM, and inattention/hyperactivity. The time reproduction task required depression of a computer key to mimic interval durations of 4, 8, 12, 16, or 20 sec. Mixed effects regression analyses were used to model accuracy and variability of time reproduction as functions of diagnostic group, interval duration, age, WM, and inattention/hyperactivity. A significant group by age interaction was detected for accuracy, with the deficit in the ASD group being greater in younger children. There was a significant group by WM interaction for consistency, with the effects of poor WM on performance consistency being more pronounced in youth with ASD. All participants tended to underestimate longer interval durations and to be less consistent for shorter interval durations; these effects appeared more pronounced in those who were younger or who had poorer WM performance. Inattention/hyperactivity symptoms in the ASD group were not related to either accuracy or consistency. This study highlights the potential value of temporal processing as an intermediate trait of relevance to multiple neurodevelopmental disorders. © 2014 International Society for Autism Research, Wiley Periodicals, Inc.

GnRH and GnRH receptors in the pathophysiology of the human female reproductive system.

PubMed

Maggi, Roberto; Cariboni, Anna Maria; Marelli, Marina Montagnani; Moretti, Roberta Manuela; Andrè, Valentina; Marzagalli, Monica; Limonta, Patrizia

2016-04-01

Human reproduction depends on an intact hypothalamic-pituitary-gonadal (HPG) axis. Hypothalamic gonadotrophin-releasing hormone (GnRH) has been recognized, since its identification in 1971, as the central regulator of the production and release of the pituitary gonadotrophins that, in turn, regulate the gonadal functions and the production of sex steroids. The characteristic peculiar development, distribution and episodic activity of GnRH-producing neurons have solicited an interdisciplinary interest on the etiopathogenesis of several reproductive diseases. The more recent identification of a GnRH/GnRH receptor (GnRHR) system in both the human endometrium and ovary has widened the spectrum of action of the peptide and of its analogues beyond its hypothalamic function. An analysis of research and review articles published in international journals until June 2015 has been carried out to comprehensively summarize both the well established and the most recent knowledge on the physiopathology of the GnRH system in the central and peripheral control of female reproductive functions and diseases. This review focuses on the role of GnRH neurons in the control of the reproductive axis. New knowledge is accumulating on the genetic programme that drives GnRH neuron development to ameliorate the diagnosis and treatment of GnRH deficiency and consequent delayed or absent puberty. Moreover, a better understanding of the mechanisms controlling the episodic release of GnRH during the onset of puberty and the ovulatory cycle has enabled the pharmacological use of GnRH itself or its synthetic analogues (agonists and antagonists) to either stimulate or to block the gonadotrophin secretion and modulate the functions of the reproductive axis in several reproductive diseases and in assisted reproduction technology. Several inputs from other neuronal populations, as well as metabolic, somatic and age-related signals, may greatly affect the functions of the GnRH pulse generator during

How Does Maternal Employment Affect Children's Socioemotional Functioning?

ERIC Educational Resources Information Center

Lam, Gigi

2015-01-01

The maternal employment becomes an irreversible trend across the globe. The effect of maternal employment on children's socioemotional functioning is so pervasive that it warrants special attention to investigate into the issue. A trajectory of analytical framework of how maternal employment affects children's socioemotional functioning originates…

The network level reproduction number for infectious diseases with both vertical and horizontal transmission.

PubMed

Xue, Ling; Scoglio, Caterina

2013-05-01

A wide range of infectious diseases are both vertically and horizontally transmitted. Such diseases are spatially transmitted via multiple species in heterogeneous environments, typically described by complex meta-population models. The reproduction number, R0, is a critical metric predicting whether the disease can invade the meta-population system. This paper presents the reproduction number for a generic disease vertically and horizontally transmitted among multiple species in heterogeneous networks, where nodes are locations, and links reflect outgoing or incoming movement flows. The metapopulation model for vertically and horizontally transmitted diseases is gradually formulated from two species, two-node network models. We derived an explicit expression of R0, which is the spectral radius of a matrix reduced in size with respect to the original next generation matrix. The reproduction number is shown to be a function of vertical and horizontal transmission parameters, and the lower bound is the reproduction number for horizontal transmission. As an application, the reproduction number and its bounds for the Rift Valley fever zoonosis, where livestock, mosquitoes, and humans are the involved species are derived. By computing the reproduction number for different scenarios through numerical simulations, we found the reproduction number is affected by livestock movement rates only when parameters are heterogeneous across nodes. To summarize, our study contributes the reproduction number for vertically and horizontally transmitted diseases in heterogeneous networks. This explicit expression is easily adaptable to specific infectious diseases, affording insights into disease evolution. Copyright © 2013 Elsevier Inc. All rights reserved.

Optical properties of functional composite silver nanoparticles and their potential use in reproductive medicine

NASA Astrophysics Data System (ADS)

Syrvatka, Vasyl J.; Slyvchuk, Yurij I.; Rozgoni, Ivan I.; Gevkan, Ivan I.; Bilyy, Oleksandr I.

2013-06-01

Silver nanoparticles are promising product of nanotechnology with attractive physicochemical and biological properties. The main aim of the study was to investigate optical properties of functional silver nanoparticles with different composite agents: polyvinylpyrrolidone, bovine serum albumin, hyaluronan and to explore their potential using in reproductive medicine. The date obtained in the study showed that surface modification of nanoparticles leads to change of their optical, physicochemical and biological properties. The optical properties of silver nanoparticles display, that AgNPs with PVP and BSA is most stable in PBS than AgNPs with HA. However the absorption curves after 120 hours of storage show, that AgNPs-HA were the most stable in ethanol. Results show, that silver nanoparticles did not effect on sperm viability and motility, but cause a changes of some biochemical parameters of conditioned medium, particular increase the concentration of triglycerides, activity of alkaline phosphatase, lactate dehydrogenase and decrease the activity of aspartate aminotransferase and alanine aminotransferase after 3 h of in vitro cultivation at 37°C. According to our latest data AgNPs with HA have a less toxic effect on biological processes in rabbits sperm compared with AgNPs with PVP and BSA. Nevertheless all functional composites of silver nanoparticles at the concentration of 0.1 μg/mL have no toxic effect on spermatozoa and can be successfully applied in reproductive medicine at low concentrations as signal enhancers, optical sensors, and biomarkers.

The impact of abnormal autoimmune function on reproduction: maternal and fetal consequences.

PubMed

Gleicher, Norbert; Weiner, Rebecca; Vietzke, Mary

2006-11-01

The impact of abnormal autoimmune function on reproductive success has remained a highly controversial issue. This is, at least partially, due to the relative lack of demographic data from women with established autoimmune diseases. We, therefore, investigated 163 women with proven autoimmune diseases and 73 controls in a demographic study of reproductive success and impact of abnormal autoimmunity on pregnancy and offspring. Women with autoimmune diseases experienced fewer pregnancies overall (p=0.04) and fewer pregnancy losses (p=0.05). Offspring from women with autoimmune diseases demonstrated a significantly increased prevalence of confirmed autoimmune diseases (p=0.04; OR 3.759; 95%CL 1.04-1.27), which increased further if suspected, but not yet confirmed, cases were added (p=0.001; OR 8.592; 95%CL 1.05-55.0). Women with autoimmune diseases exhibited a trend towards lower cesarean section delivery during their own birth and a significantly increased prevalence of disease in vaginally delivered offspring (p=0.014; OR 6.041; 95%CL 1.32-38.22). Autoimmune diseases impair female fecundity even before the diseases become clinically overt. Offspring are at increased risk to develop autoimmune diseases, though they may differ from those of their mothers. This risk appears to correlate with mode of delivery and may be the consequence of varying cell traffic dynamics with vaginal and cesarean section deliveries.

Reproductive function in male endurance athletes: sperm analysis and hormonal profile.

PubMed

Lucía, A; Chicharro, J L; Pérez, M; Serratosa, L; Bandrés, F; Legido, J C

1996-12-01

The purpose of this investigation was to study the effects of endurance exercise on male reproductive function (sex hormones and seminograms). Professional cyclists [n = 12; mean age 24 +/- 2 (SD) yr], elite triathletes (n = 9; 26 +/- 3 yr), recreational marathon runners (n = 10; 32 +/- 6 yr), and sedentary subjects (control group; n = 9; 30 +/- 4 yr) were selected as subjects. for each group, the following parameters were measured three times during the sports season (training period: winter; competition period: spring; resting period: fall): percentage of body fat, hormonal profile (resting levels of follicle-stimulating hormone, luteinizing hormone, total and free testosterone, and cortisol), and seminograms (quantitative parameters sperm volume and sperm count; qualitative parameters: sperm motality and morphology). The following comparisons were made in the measured parameters: 1) within groups (longitudinal design) and 2) between groups in each of the three periods (cross-sectional design) and over time (mixed design). In addition, both the volume and the intensity of training of each subject during the season (except for the control group) were quantified. Despite significant differences in training characteristics and in body fat percent, in general no significant differences (P > 0.05) were found in hormonal profiles or in semen characteristics between or within groups. A lower sperm motility (46.2 +/- 19.5%), however, was observed in the cyclists during the competition period when compared either with the other groups during this same period (P < 0.05) or with themselves during the other two periods of study (P < 0.01). In any case, the later phenomenon was attributed to physical factors associated with cycling, such as mechanical trauma to the testis and/or increased gonadal temperature. In conclusion, our findings suggest that endurance exercise does not adversely affect the hypothalamic-pituitary-testis axis.

Reproductive policy and the social construction of motherhood.

PubMed

Bonnie, Stabile

2016-01-01

Reproductive technologies allow women to embrace or forgo motherhood, but a woman's ability to make autonomous reproductive choices depends on access to these technologies. In the United States, public policies - laws, regulations, appropriations, and rulings - have either broadened or narrowed this access. Have U.S. public policies affecting reproductive choices conformed to attitudinal distinctions about motherhood itself? I identified policies covering infertility, contraception, and abortion and examined them contextually within the Ingram-Schneider social construction framework. Women's choices fell within social construction quadrants as being positively portrayed and powerful; negatively portrayed but powerful; positively portrayed but powerless; and negatively portrayed and powerless. Married heterosexual women embracing motherhood were likely to be viewed positively and to reap benefits. Women forgoing motherhood, poor women, and women seeking to form nontraditional families were likely to be viewed negatively and to bear burdens; critical among these burdens was restriction of access to technologies that could be used to support a decision to avoid motherhood or to achieve motherhood through nontraditional methods. Yes, U.S. public policies affecting reproductive choices have conformed to attitudinal distinctions about motherhood itself. These policies may also have altered those choices.

Effects of the workplace on fertility and related reproductive outcomes.

PubMed Central

Baranski, B

1993-01-01

This report reviews the recent literature on the adverse effects of occupational factors on fertility and related reproductive outcomes. Few studies fulfill the criteria of good study design because of small sample size, insensitive measures of effect, selection, recall, and observation bias, weak if any control of confounding factors, bad definition of exposure, inability to analyze a dose-response relationship, and inadequate statistical analysis. The high prevalence of unsuccessful reproductive outcomes in the general population makes the design of human fertility studies difficult. Although a number of publications indicate that certain occupational factors and settings adversely affect both male and female fertility, it is virtually impossible to estimate the proportion of infertility due to occupational factors in the general population. The collected data suggest that the exposure to the following substances or occupational settings may affect a function of male genital system, leading to sperm abnormalities, hyperestrogenism, impotence, infertility, and/or increased spontaneous abortion rate in wives of exposed workers: alkylmercury, antimonide, anesthetic gases, boron, carbon disulfide, chlorodecone, chloroprene, some carbamates (carbaryl), diaminostilbene, 1,2-dibromo-3-chloropropane, ethylene glycol ethers, ethylene dibromide, inorganic lead, manganese, methyl chloride, organic solvents, synthetic estrogens and progestins, tetraethyllead, combined exposure to styrene and acetone, welding operations, and heat. The majority of reviewed papers on female fertility concerns the alterations of menstrual cycle and pregnancy complications rather than occupational exposure-induced female infertility. The literature supports the hypothesis that, in general, working women have a tendency of higher risk of unsuccessful reproductive outcomes, although the existing data are not sufficient. PMID:8243410

Gestational Exposure to Bisphenol A Affects the Function and Proteome Profile of F1 Spermatozoa in Adult Mice.

PubMed

Rahman, Md Saidur; Kwon, Woo-Sung; Karmakar, Polash Chandra; Yoon, Sung-Jae; Ryu, Buom-Yong; Pang, Myung-Geol

2017-02-01

Maternal exposure to the endocrine disruptor bisphenol A (BPA) has been linked to offspring reproductive abnormalities. However, exactly how BPA affects offspring fertility remains poorly understood. The aim of the present study was to evaluate the effects of gestational BPA exposure on sperm function, fertility, and proteome profile of F1 spermatozoa in adult mice. Pregnant CD-1 mice (F0) were gavaged with BPA at three different doses (50 μg/kg bw/day, 5 mg/kg bw/day, and 50 mg/kg bw/day) on embryonic days 7 to 14. We investigated the function, fertility, and related processes of F1 spermatozoa at postnatal day 120. We also evaluated protein profiles of F1 spermatozoa to monitor their functional affiliation to disease. BPA inhibited sperm count, motility parameters, and intracellular ATP levels in a dose-dependent manner. These effects appeared to be caused by reduced numbers of stage VIII seminiferous epithelial cells in testis and decreased protein kinase A (PKA) activity and tyrosine phosphorylation in spermatozoa. We also found that BPA compromised average litter size. Proteins differentially expressed in spermatozoa from BPA treatment groups are known to play a critical role in ATP generation, oxidative stress response, fertility, and in the pathogenesis of several diseases. Our study provides mechanistic support for the hypothesis that gestational exposure to BPA alters sperm function and fertility via down-regulation of tyrosine phosphorylation through a PKA-dependent mechanism. In addition, we anticipate that the BPA-induced changes in the sperm proteome might be partly responsible for the observed effects in spermatozoa. Citation: Rahman MS, Kwon WS, Karmakar PC, Yoon SJ, Ryu BY, Pang MG. 2017. Gestational exposure to bisphenol-A affects the function and proteome profile of F1 spermatozoa in adult mice. Environ Health Perspect 125:238-245; http://dx.doi.org/10.1289/EHP378.

Affective disorders and sexual function: from neuroscience to clinic.

PubMed

Barata, Bernardo C

2017-11-01

Sexual dysfunction is a frequent issue in patients with affective disorders, affecting its quality of life and posing challenges to the approach of these patients. In recent years, human sexuality has attracted interest from the scientific community, and today we have a much deeper knowledge of the mechanisms involved in the sexual response. Paraphilias or sexual dysfunctions like low sexual desire, premature ejaculation, and erectile dysfunction, are frequent in affective disorders, and the frequency of each sexual problem varies according to the affective disorder. Comparing what is currently known about the sexual response with the main neurobiological findings of depressive, anxiety, obsessive-compulsive and posttraumatic stress disorders, it is possible to better understand specific sexual complaints of patients with these disorders. A better understanding of sexual function in affective disorders may help clinicians to choose treatments more suited to specific needs of these patients. Although the current state of science already allows us to have some understanding about sexual function in affective disorders, this critical area of research is still in its infancy, waiting for more investment.

Reproductive responses to photoperiod persist in olfactory bulbectomized Siberian hamsters (Phodopus sungorus).

PubMed

Prendergast, Brian J; Pyter, Leah M; Galang, Jerome; Kay, Leslie M

2009-03-02

In reproductively photoperiodic Syrian hamsters, removal of the olfactory bulbs (OBx) leads to a marked and sustained increase in gonadotrophin secretion which prevents normal testicular regression in short photoperiods. In contrast, among reproductively nonphotoperiodic laboratory strains of rats and mice, bulbectomy unmasks reproductive responses to photoperiod. The role of the olfactory bulbs has been proposed to have opposite effects on responsiveness to photoperiod, depending on the photoperiodicity of the reproductive system; however, Syrian hamsters are the only reproductively photoperiodic rodent species for which the role of the olfactory bulb in reproductive endocrinology has been assessed. This experiment evaluated the role of the olfactory bulbs in the photoperiodic control of reproduction in Siberian hamsters (Phodopus sungorus), an established model species for the study of neural substrates mediating seasonality. Relative to control hamsters housed in long days (15 h light/day), exposure of adult male hamsters to short days (9h light/day) for 8 weeks led to a temporal expansion of the pattern of nocturnal locomotor activity, testicular regression, decreases in testosterone (T) production, and undetectable levels of plasma follicle-stimulating hormone (FSH). Bilateral olfactory bulbectomy failed to affect any of these responses to short days. The patterns of entrainment to long and short days suggests that pre-pineal mechanisms involved in photoperiodic timekeeping are functioning normally in OBx hamsters. The absence of increases in FSH following bulbectomy in long days is incompatible with the hypothesis that the olfactory bulbs provide tonic inhibition of the HPG axis in this species. In marked contrast to Syrian hamsters, the olfactory bulbs of Siberian hamsters play essentially no role in the modulation of tonic gonadotrophin production or gonadotrophin responses to photoperiod.

An Overview of the Function and Maintenance of Sexual Reproduction in Dikaryotic Fungi

PubMed Central

Wallen, R. M.; Perlin, Michael H.

2018-01-01

Sexual reproduction likely evolved as protection from environmental stresses, specifically, to repair DNA damage, often via homologous recombination. In higher eukaryotes, meiosis and the production of gametes with allelic combinations different from parental type provides the side effect of increased genetic variation. In fungi it appears that while the maintenance of meiosis is paramount for success, outcrossing is not a driving force. In the subkingdom Dikarya, fungal members are characterized by existence of a dikaryon for extended stages within the life cycle. Such fungi possess functional or, in some cases, relictual, loci that govern sexual reproduction between members of their own species. All mating systems identified so far in the Dikarya employ a pheromone/receptor system for haploid organisms to recognize a compatible mating partner, although the paradigm in the Ascomycota, e.g., Saccharomyces cerevisiae, is that genes for the pheromone precursor and receptor are not found in the mating-type locus but rather are regulated by its products. Similarly, the mating systems in the Ascomycota are bipolar, with two non-allelic idiomorphs expressed in cells of opposite mating type. In contrast, for the Basidiomycota, both bipolar and tetrapolar mating systems have been well characterized; further, at least one locus directly encodes the pheromone precursor and the receptor for the pheromone of a different mating type, while a separate locus encodes proteins that may regulate the first locus and/or additional genes required for downstream events. Heterozygosity at both of two unlinked loci is required for cells to productively mate in tetrapolar systems, whereas in bipolar systems the two loci are tightly linked. Finally, a trade-off exists in wild fungal populations between sexual reproduction and the associated costs, with adverse conditions leading to mating. For fungal mammal pathogens, the products of sexual reproduction can be targets for the host immune

Prostaglandins and reproduction in female farm animals.

PubMed

Weems, C W; Weems, Y S; Randel, R D

2006-03-01

Prostaglandins impact on ovarian, uterine, placental, and pituitary function to regulate reproduction in female livestock. They play important roles in ovulation, luteal function, maternal recognition of pregnancy, implantation, maintenance of gestation, microbial-induced abortion, parturition, postpartum uterine and ovarian infections, and resumption of postpartum ovarian cyclicity. Prostaglandins have both positive and negative effects on reproduction; they are used to synchronize oestrus, terminate pseudopregnancy in mares, induce parturition, and treat retained placenta, luteinized cysts, pyometra, and chronic endometritis. Improved therapeutic uses for prostaglandins will be developed when we understand better their involvement in implantation, maintenance of luteal function, and establishment and maintenance of pregnancy.

Nocturnal illumination maintains reproductive function and simulates the period-lengthening effect of constant light in the mature male Djungarian hamster (Phodopus sungorus)

NASA Technical Reports Server (NTRS)

Ferraro, J. S.

1990-01-01

Mature male Djungarian hamsters (Phodopus sungorus) were placed in individual light-tight, sound attenuated chambers and exposed to one of four lighting conditions for a duration of approximately seven weeks. The four lighting conditions were: constant light (LL); constant dark (DD); feedback lighting (LDFB; a condition that illuminates the cage in response to locomotor activity); or a feedback lighting neighbor control (LDFB NC; the animal receives the same light pattern as a paired animal in feedback lighting, but has no control over it). Exposure of hamsters to LL or LDFB produced significantly and similarly longer free-running periods of the locomotor activity rhythm than exposure of animals to DD. Hamsters exposed to LDFB NC did not free-run or entrain, but rather displayed "relative coordination". The paired testes and sex accessory glands weights suggest that in the Djungarian hamster, LL and LDFB exposed animals maintained reproductive function, whereas DD exposed animals did not. Animals exposed to LDFB NC had intermediate paired testes weights. Since several previous studies have demonstrated that short pulses of light, which are coincident with the subjective night, are photostimulatory, it is not surprising that LDFB maintained reproductive function in the mature Djungarian hamster. Feedback lighting, however, has been shown to be an insufficient stimulus to maintain reproductive function of mature male and female Syrian hamsters, and to the reproductive maturation of immature Djungarian hamsters. The results suggest that there may be slight, but significant differences in the way these two species interpret photoperiod, as well as a developmental change in the photoperiodic response of Djungarian hamsters.

Intermittent fasting during winter and spring affects body composition and reproduction of a migratory duck

USGS Publications Warehouse

Barboza, P.S.; Jorde, Dennis G.

2002-01-01

We compared food intake, body mass and body composition of male and female black ducks (Anas rubripes) during winter (January-March). Birds were fed the same complete diet ad libitum on consecutive days each week without fasting (control; nine male; nine female) or with either short fasts (2 day.week-1; nine male; nine female), or long fasts (4 day.week-1; eleven male; twelve female). We continued treatments through spring (March-May) to measure the effect of intermittent fasts on body mass and egg production. Daily food intake of fasted birds was up to four times that of unfasted birds. Weekly food intake of males was similar among treatments (364 g.kg-1.week-1) but fasted females consumed more than unfasted females in January (363 g.kg-1.week-1 vs. 225 g.kg-1.week-1). Although both sexes lost 10-14% body mass, fasted females lost less mass and lipid than unfasted females during winter. Total body nitrogen was conserved over winter in both sexes even though the heart and spleen lost mass while the reproductive tract and liver gained mass. Intermittent fasting increased liver, intestinal tissue and digesta mass of females but not of males. Fasting delayed egg production in spring but did not affect size, fertility or hatching of the clutch. Females on long fasts were still heavier than controls after laying eggs. Thus black ducks combine flexibility of food intake with plasticity of digestive tract, liver and adipose tissue when food supply is interrupted during winter. Females modulate body mass for survival and defer reproduction when food supply is interrupted in spring.

The impact of reproduction on the stress axis of free-living male northern red backed voles (Myodes rutilus).

PubMed

Fletcher, Quinn E; Dantzer, Ben; Boonstra, Rudy

2015-12-01

Activation of the hypothalamic-pituitary-adrenal (HPA) axis culminates in the release of glucocorticoids (henceforth CORT), which have wide-reaching physiological effects. Three hypotheses potentially explain seasonal variation in CORT. The enabling hypothesis predicts that reproductive season CORT exceeds post-reproductive season CORT because CORT enables reproductive investment. The inhibitory hypothesis predicts the opposite because CORT can negatively affect reproductive function. The costs of reproduction hypothesis predicts that HPA axis condition declines over and following the reproductive season. We tested these hypotheses in wild male red-backed voles (Myodes rutilus) during the reproductive and post-reproductive seasons. We quantified CORT levels in response to restraint stress tests consisting of three blood samples (initial, stress-induced, and recovery). Mineralocorticoid (MR) and glucocorticoid (GR) receptor mRNA levels in the brain were also quantified over the reproductive season. Total CORT (tCORT) in the initial and stress-induced samples were greater in the post-reproductive than in the reproductive season, which supported the inhibitory hypothesis. Conversely, free CORT (fCORT) did not differ between the reproductive and post-reproductive seasons, which was counter to both the enabling and inhibitory hypotheses. Evidence for HPA axis condition decline in CORT as well as GR and MR mRNA over the reproductive season (i.e. costs of reproduction hypothesis) was mixed. Moreover, all of the parameters that showed signs of declining condition over the reproductive season did not also show signs of declining condition over the post-reproductive season suggesting that the costs resulting from reproductive investment had subsided. In conclusion, our results suggest that different aspects of the HPA axis respond differently to seasonal changes and reproductive investment. Copyright © 2015 Elsevier Inc. All rights reserved.

[Importance of microbiologic examination of vaginal secretions in the reproductive period].

PubMed

Arsić-Arsenijević, Valentina; Radonjić, Ivana; Mijac, Vera; Cirković, Ivana

2004-01-01

Vaginal infections, during reproductive period are frequent and although not life treating, they can affect their normal functions. They can also affect women's fertility as well as the course of pregnancy. The outcome of pregnancy can be endangered due to the possibility of infection of newborn while passing trough birth canal of the infected mother. As statistically shown, bacterial vaginosis is considerably more often found with the patients having precancerous changes on cervix, or diagnosed cancer of cervix, comparing with women with healthy cervix. It can also cause the appearance of postoperative pelvic cellulitis after hysterectomy. On the other side, the presence of S. agalactiae in vaginal secretion may cause very serious and lethal infections of the newborn such as meningitis, pneumonia and sepsis. As for protozoa T. vaginalis it has been shown that it could cause reduced fertility ability and that during pregnancy it could damage fetal membranes and bring to its premature rupture and premature birth. There is also increased risk of cervix cancer. During reproductive period of women especially if risk factors are existing such as hormone therapy, diabetes mellitus type 1 and applications of wide range antibiotics, vaginal fungal infections caused by Candida can frequently appear. These infection apart from the discomfort like itch and affluent secretion they can also mean diagnostic and therapeutical problem. Regular microbiological test of women are highly recommended during reproductive period as standard for bacterial vaginosis, fungal and trichomonas infections. If those results appear negative, further microbiological tests are necessary. Such tests which are more elaborate, more timely and more expensive are referring to tests on chlamydia, microplasma and some viruses that can also be the cause of vaginal secretion disbalance in women during reproductive period.

Bioinformatics for spermatogenesis: annotation of male reproduction based on proteomics

PubMed Central

Zhou, Tao; Zhou, Zuo-Min; Guo, Xue-Jiang

2013-01-01

Proteomics strategies have been widely used in the field of male reproduction, both in basic and clinical research. Bioinformatics methods are indispensable in proteomics-based studies and are used for data presentation, database construction and functional annotation. In the present review, we focus on the functional annotation of gene lists obtained through qualitative or quantitative methods, summarizing the common and male reproduction specialized proteomics databases. We introduce several integrated tools used to find the hidden biological significance from the data obtained. We further describe in detail the information on male reproduction derived from Gene Ontology analyses, pathway analyses and biomedical analyses. We provide an overview of bioinformatics annotations in spermatogenesis, from gene function to biological function and from biological function to clinical application. On the basis of recently published proteomics studies and associated data, we show that bioinformatics methods help us to discover drug targets for sperm motility and to scan for cancer-testis genes. In addition, we summarize the online resources relevant to male reproduction research for the exploration of the regulation of spermatogenesis. PMID:23852026

Effects of marine toxins on the reproduction and early stages development of aquatic organisms.

PubMed

Vasconcelos, Vítor; Azevedo, Joana; Silva, Marisa; Ramos, Vítor

2010-01-19

Marine organisms, and specially phytoplankton species, are able to produce a diverse array of toxic compounds that are not yet fully understood in terms of their main targets and biological function. Toxins such as saxitoxins, tetrodotoxin, palytoxin, nodularin, okadaic acid, domoic acid, may be produced in large amounts by dinoflagellates, cyanobacteria, bacteria and diatoms and accumulate in vectors that transfer the toxin along food chains. These may affect top predator organisms, including human populations, leading in some cases to death. Nevertheless, these toxins may also affect the reproduction of aquatic organisms that may be in contact with the toxins, either by decreasing the amount or quality of gametes or by affecting embryonic development. Adults of some species may be insensitive to toxins but early stages are more prone to intoxication because they lack effective enzymatic systems to detoxify the toxins and are more exposed to the toxins due to a higher metabolic growth rate. In this paper we review the current knowledge on the effects of some of the most common marine toxins on the reproduction and development of early stages of some organisms.

Reproduction in the space environment: Part II. Concerns for human reproduction

NASA Technical Reports Server (NTRS)

Jennings, R. T.; Santy, P. A.

1990-01-01

Long-duration space flight and eventual colonization of our solar system will require successful control of reproductive function and a thorough understanding of factors unique to space flight and their impact on gynecologic and obstetric parameters. Part II of this paper examines the specific environmental factors associated with space flight and the implications for human reproduction. Space environmental hazards discussed include radiation, alteration in atmospheric pressure and breathing gas partial pressures, prolonged toxicological exposure, and microgravity. The effects of countermeasures necessary to reduce cardiovascular deconditioning, calcium loss, muscle wasting, and neurovestibular problems are also considered. In addition, the impact of microgravity on male fertility and gamete quality is explored. Due to current constraints, human pregnancy is now contraindicated for space flight. However, a program to explore effective countermeasures to current constraints and develop the required health care delivery capability for extended-duration space flight is suggested. A program of Earth- and space-based research to provide further answers to reproductive questions is suggested.

Androgens and the male reproductive tract: an overview of classical roles and current perspectives.

PubMed

Patrão, Marilia T C C; Silva, Erick J R; Avellar, Maria Christina W

2009-11-01

Androgens are steroid hormones that play key roles in the development and maintenance of male phenotype and reproductive function. These hormones also affect the function of several non-reproductive organs, such as bone and skeletal muscle. Endogenous androgens exert most of their effects by genomic mechanisms, which involve hormone binding to the androgen receptor (AR), a ligand-activated transcription factor, resulting in the modulation of gene expression. AR-induced non-genomic mechanisms have also been reported. A large number of steroidal and non-steroidal AR-ligands have been developed for therapeutic use, including the treatment of male hypogonadism (AR agonists) and prostate diseases (AR antagonists), among other pathological conditions. Here, the AR gene and protein structure, mechanism of action and AR gene homologous regulation were reviewed. The AR expression pattern, its in vivo regulation and physiological relevance in the developing and adult testis and epididymis, which are sites of sperm production and maturation, respectively, were also presented.

Effects of Environmental Toxicants on the Neuroendocrine Control of Female Reproduction

EPA Science Inventory

The hypothalamus and pituitary are known to play key roles in reproductive function. A growing body of evidence indicates that environmental toxicants can alter female reproductive function by disrupting hypothalamic control of the pituitary and subsequently, the endocrine contro...

Sex differences in the drivers of reproductive skew in a cooperative breeder.

PubMed

Nelson-Flower, Martha J; Flower, Tom P; Ridley, Amanda R

2018-04-16

Many cooperatively breeding societies are characterized by high reproductive skew, such that some socially dominant individuals breed, while socially subordinate individuals provide help. Inbreeding avoidance serves as a source of reproductive skew in many high-skew societies, but few empirical studies have examined sources of skew operating alongside inbreeding avoidance or compared individual attempts to reproduce (reproductive competition) with individual reproductive success. Here, we use long-term genetic and observational data to examine factors affecting reproductive skew in the high-skew cooperatively breeding southern pied babbler (Turdoides bicolor). When subordinates can breed, skew remains high, suggesting factors additional to inbreeding avoidance drive skew. Subordinate females are more likely to compete to breed when older or when ecological constraints on dispersal are high, but heavy subordinate females are more likely to successfully breed. Subordinate males are more likely to compete when they are older, during high ecological constraints, or when they are related to the dominant male, but only the presence of within-group unrelated subordinate females predicts subordinate male breeding success. Reproductive skew is not driven by reproductive effort, but by forces such as intrinsic physical limitations and intrasexual conflict (for females) or female mate choice, male mate-guarding and potentially reproductive restraint (for males). Ecological conditions or "outside options" affect the occurrence of reproductive conflict, supporting predictions of recent synthetic skew models. Inbreeding avoidance together with competition for access to reproduction may generate high skew in animal societies, and disparate processes may be operating to maintain male vs. female reproductive skew in the same species. © 2018 John Wiley & Sons Ltd.

Reproductive effort affects oxidative status and stress in an Antarctic penguin species: An experimental study.

PubMed

Colominas-Ciuró, Roger; Santos, Mercedes; Coria, Néstor; Barbosa, Andrés

2017-01-01

The oxidative cost of reproduction has been a matter of debate in recent years presumably because of the lack of proper experimental studies. Based on the hypothesis that different brood sizes produce differential reproductive costs, an experimental manipulation during breeding of Adélie penguins was conducted at Hope Bay, Antarctica, to study oxidative status and stress. We predict that a lower reproductive effort should be positively related to low oxidative and physiological stress. We randomly assigned nests with two chicks to a control reproductive effort group (CRE), and by removing one chick from some nests with two chicks, formed a second, low reproductive effort group (LRE). We examined how oxidative status in blood plasma (reactive oxygen metabolites, ROMs, and total antioxidant capacity, OXY) and stress (heterophil/lymphocyte ratio, H/L) responded to a lower production of offspring total biomass. Our nest manipulation showed significant differences in offspring total biomass, which was lower in the LRE group. As predicted, the LRE group had higher antioxidant capacity than individuals in the CRE group. We have also found, although marginally significant, interactions between sex and treatment in the three variables analysed. Females had higher OXY, lower ROMs and lower H/L ratio when rearing one chick, whereas males did so when rearing two except for OXY which was high regardless of treatment. Moreover, there was a significant negative correlation between the H/L ratio and OXY in females. Finally, we have found a negative and significant relationship between the duration of the experiment and OXY and ROMs and positive with H/L ratio which suggests that indeed breeding penguins are paying an effort in physiological terms in relation to the duration of the chick rearing. In conclusion, a reduction of the reproductive effort decreased oxidative stress in this long-lived bird meaning that a link exists between breeding effort and oxidative stress. However

Influence of water flow on Neosho madtom (Noturus placidus) reproductive behavior

USGS Publications Warehouse

Bryan, J.L.; Wildhaber, M.L.; Noltie, Douglas B.

2006-01-01

The Neosho madtom is a small, short-lived catfish species endemic to gravel bars of the Neosho River in Kansas, Oklahoma and Missouri, U.S.A. It spawns during summer in nesting cavities excavated in gravel. Although the species has survived dam construction within the Neosho River basin, its declining numbers resulted in it being added to the federal threatened species list in 1991. To test how water flow affects the reproductive behavior of Neosho madtoms, we compared activities of male-female pairs in static versus flowing-water aquaria. Using a behavioral catalog, we recorded their behavior sequences during randomly selected 5-min nighttime periods. For males and females, Jostle and Embrace were the most performed reproductive behaviors and the Jostle-Embrace-Carousel was the most performed reproductive behavior sequence. Water flow decreased the mean frequency of occurrence, percentage of time spent and mean event duration of male Nest Building. Because Neosho madtom courtship, reproduction and parental care is a complex and extended process, disturbances such as heightened river flows during the species' spawning season may negatively affect nest quality and reproductive success.

Foods That Can Affect Fertility

MedlinePlus

... Reproduction Foods That Can Affect Fertility Print Email Foods That Can Affect Fertility By Caroline Kaufman, MS, ... to a registered dietitian nutritionist. Choose Iron-Rich Foods An diet rich in iron that comes from ...

Mutation independently affects reproductive traits and dauer larvae development in mutation accumulation lines of Caenorhabditis elegans.

PubMed

Hills, Arthur J; Green, James W M; Harvey, Simon C

2017-11-01

Developmental decisions are important in organismal fitness. For the nematode Caenorhabditis elegans, which is naturally found in the ephemeral food patches formed by rotting plant material, correctly committing to dauer or non-dauer larval development is key to genotype survival. To investigate the link between reproductive traits, which will determine how populations grow, and dauer larvae formation, we have analysed these traits in mutation accumulation lines of C. elegans. We find that reproductive traits of individual worms-the total number of progeny and the timing of progeny production-are highly correlated with the population size observed in growing populations. In contrast, we find no relationship between reproduction traits and the number of dauer larvae observed in growing populations. We also do not observe a mutational bias in dauer larvae formation. These results indicate that the control of dauer larvae formation is distinct from the control of reproduction and that differences in dauer larvae formation can evolve rapidly.

ATP-binding cassette transporters in reproduction: a new frontier

PubMed Central

Bloise, E.; Ortiga-Carvalho, T.M.; Reis, F.M.; Lye, S.J.; Gibb, W.; Matthews, S.G.

2016-01-01

BACKGROUND The transmembrane ATP-binding cassette (ABC) transporters actively efflux an array of clinically relevant compounds across biological barriers, and modulate biodistribution of many physiological and pharmacological factors. To date, over 48 ABC transporters have been identified and shown to be directly and indirectly involved in peri-implantation events and fetal/placental development. They efflux cholesterol, steroid hormones, vitamins, cytokines, chemokines, prostaglandins, diverse xenobiotics and environmental toxins, playing a critical role in regulating drug disposition, immunological responses and lipid trafficking, as well as preventing fetal accumulation of drugs and environmental toxins. METHODS This review examines ABC transporters as important mediators of placental barrier functions and key reproductive processes. Expression, localization and function of all identified ABC transporters were systematically reviewed using PubMed and Google Scholar websites to identify relevant studies examining ABC transporters in reproductive tissues in physiological and pathophysiological states. Only reports written in English were incorporated with no restriction on year of publication. While a major focus has been placed on the human, extensive evidence from animal studies is utilized to describe current understanding of the regulation and function of ABC transporters relevant to human reproduction. RESULTS ABC transporters are modulators of steroidogenesis, fertilization, implantation, nutrient transport and immunological responses, and function as ‘gatekeepers’ at various barrier sites (i.e. blood-testes barrier and placenta) against potentially harmful xenobiotic factors, including drugs and environmental toxins. These roles appear to be species dependent and change as a function of gestation and development. The best-described ABC transporters in reproductive tissues (primarily in the placenta) are the multidrug transporters p-glycoprotein and

Subtle effect of Xenos vesparum (Xenidae, Strepsiptera) on the reproductive apparatus of its male host: Parasite or parasitoid?

PubMed

Beani, L; Marchini, D; Cappa, F; Petrocelli, I; Gottardo, M; Manfredini, F; Giusti, F; Dallai, R

2017-08-01

Parasitic castration is an adaptive strategy where parasites usurp the hosts' reproductive physiology to complete their life cycle. The alterations in the host traits vary in their magnitude, from subtle changes in the host morpho-physiology and behaviour to the production of complex aberrant phenotypes, which often depend on the host gender. The strepsipteran macroparasite Xenos vesparum induces dramatic behavioural and physiological changes in its female host, the paper wasp Polistes dominula, while its effect on the male phenotype is largely unknown. In this study we investigated how a single X. vesparum parasite influences the functional morphology of P. dominula male reproductive apparatus. We performed morphometry and ultrastructure characterization of corpora allata, testes, seminal vesicles and accessory glands in parasitized and unparasitized males, and also in young and old males to control for the effect of age on the natural deterioration of these organs. Our results show that age significantly affects the development of male reproductive apparatus. A low parasite load - one parasite per host is the common prevalence in the field - has only a marginal impact on the reproductive morphology of P. dominula males, affecting quantitatively but not qualitatively the protein content of male accessory glands. Thus, in male P. dominula wasps, X. vesparum appears to behave as a true "parasite", in clear opposition to the role of "parasitoid" that it takes in female hosts where castration causes the reproductive death. Copyright © 2017 Elsevier Ltd. All rights reserved.

Lectin-functionalized magnetic iron oxide nanoparticles for reproductive improvement

USDA-ARS?s Scientific Manuscript database

Background: Semen ejaculates contain heterogeneous sperm populations that can jeopardize male fertility. Recent development of nanotechnology in physiological systems may have applications in reproductive biology. Here, we used magnetic nanoparticles as a novel strategy for sperm purification to imp...

Endocrine control of epigenetic mechanisms in male reproduction.

PubMed

Ankolkar, Mandar; Balasinor, N H

2016-01-01

Endocrine control of reproduction is very well known and has been echoed by many research groups. However, recent developments point to the ability of toxic endocrine disrupting chemicals (EDC) to alter epigenetic information of the gametes which gets transferred to the developing embryo and affects the immediate reproductive outcome or even persists transgenerationally. These epigenetic aberrations contribute to the ensuing pathophysiology of reproductive disorders. Investigations of the female in cases of poor reproductive outcome have been the main strategy towards diagnosis. However, despite the male partner contributing half of his genome to the progeny, thorough investigations in the male have been ignored. Environmental pollutants are all pervading and are encountered in our day-to-day life. Many of these pollutants have potential to disrupt the endocrine system. Here, we discuss how the male gametes (spermatozoa) are susceptible to a myriad of epigenetic insults inflicted by exposure to endocrine disruptors and how important is the contribution of the epigenetic marks of the spermatozoa in healthy reproduction. We advocate that sperm epigenetics should be considered as a significant contributor to reproductive health and should be researched further and be subsequently included in routine diagnostic workup in cases of poor reproductive outcome.

Gender and social reproduction: historical perspectives.

PubMed

Laslett, B; Brenner, J

1989-01-01

It is argued that gender relations and social reproduction were both shaped by macrohistorical processes and shaped the processes. Social reproduction is defined within feminist theory as more than production in the Marxist sense. Societal reproduction is a combination of the organization of production, the organization of social reproduction, the perpetuation of gender, and the continuation of class relations. Social reproduction includes the care and socialization of children and care of the elderly or infirm. Social reproduction includes the organization of sexuality, biological reproduction, and how food, clothing, and shelter are made available. Most social reproduction occurs within the family unit. It is pointed out that variations in the distribution of the work of social reproduction are affected by the family, market, community, and state. The ways in which women construct their own worlds of activity is a central concern. The feminist concept of social reproduction differs from modernization theory, which is concerned with the institutional location of the tasks of social reproduction and the structural effects on the family and gender relations. This literature review focuses only on the history of family strategies and separate gender-related activities. The authors describe the changes in family organization that define men as income producers and women as caretakers, who base child rearing on love and feminine virtue rather than patriarchal authority and religious doctrine. The discussion focuses on the differences in marital relationships, motherhood, and sexuality between upper and middle class and working class women in the 19th century. Among working class women, a good wife was an efficient manager, a skilled domestic worker, and an income earner. The turn of the century was a period of social change marked by smaller average family size, the decline of household production, the rise in real wages, and increased consumption. It is argued that

Tribbles role in reproduction.

PubMed

Basatvat, Shaghayegh; Carter, Deborah Angela Louise; Kiss-Toth, Endre; Fazeli, Alireza

2015-10-01

Tribbles (TRIB) proteins, a family of evolutionary conserved psuedokinase proteins, modulate various signalling pathways within the cell. The regulatory roles of TRIB make them an important part of a number of biological processes ranging from cell proliferation to metabolism, immunity, inflammation and carcinogenesis. Innate immune system plays a pivotal role during the regulation of reproductive processes that allows successful creation of an offspring. Its involvement initiates from fertilization of the oocyte by spermatozoon and lasts throughout early embryonic development, pregnancy and labour. Therefore, there is a close cooperation between the reproductive system and the innate immune system. Evidence from our lab has demonstrated that improper activation of the innate immune system can reduce embryo implantation, thus leading to infertility. Therefore, control mechanisms regulating the innate immune system function can be critical for successful reproductive events. © 2015 Authors; published by Portland Press Limited.

Acute brief heat stress in late gestation alters neonatal calf innate immune functions

USDA-ARS?s Scientific Manuscript database

Heat stress (HS), as one of the environmental stressors affecting the dairy industry, compromises the cow's milk production, immune function, and reproductive system. However, few studies have looked at how prenatal HS affects the offspring. The objective of this study was to evaluate the effect of ...

Resource allocation to reproduction in animals.

PubMed

Kooijman, Sebastiaan A L M; Lika, Konstadia

2014-11-01

The standard Dynamic Energy Budget (DEB) model assumes that a fraction κ of mobilised reserve is allocated to somatic maintenance plus growth, while the rest is allocated to maturity maintenance plus maturation (in embryos and juveniles) or reproduction (in adults). All DEB parameters have been estimated for 276 animal species from most large phyla and all chordate classes. The goodness of fit is generally excellent. We compared the estimated values of κ with those that would maximise reproduction in fully grown adults with abundant food. Only 13% of these species show a reproduction rate close to the maximum possible (assuming that κ can be controlled), another 4% have κ lower than the optimal value, and 83% have κ higher than the optimal value. Strong empirical support hence exists for the conclusion that reproduction is generally not maximised. We also compared the parameters of the wild chicken with those of races selected for meat and egg production and found that the latter indeed maximise reproduction in terms of κ, while surface-specific assimilation was not affected by selection. We suggest that small values of κ relate to the down-regulation of maximum body size, and large values to the down-regulation of reproduction. We briefly discuss the ecological context for these findings. © 2014 The Authors. Biological Reviews © 2014 Cambridge Philosophical Society.

Physical activity and its effects on reproduction.

PubMed

Redman, Leanne M

2006-05-01

The reproductive system is tightly coupled with energy balance, and thereby changes in the status of energy balance through changes in physical activity can impact on the reproductive system. In light of the new physical activity for health recommendations, it is therefore important to understand the inherent effects, both positive and negative, of physical activity on the reproductive system. At both extremes of the energy spectrum, disorders of chronic energy excess and energy deficiency are characterized by a wide range of reproductive disorders, including menstrual irregularity, anovulation, polycystic ovarian syndrome, and infertility in women, and erectile dysfunction and altered spermatogenesis in men. Although laboratory research indicates that individuals may be able to prevent or reverse reproductive disruptions, either by increasing energy expenditure in cases of energy excess or by dietary reform in cases of energy deficits, there is an acute need for applied research to confirm this idea and to identify mechanisms by which the availability of energy per se regulates reproductive function in humans.

Amino acid metabolism in intestinal bacteria and its potential implications for mammalian reproduction.

PubMed

Dai, Zhaolai; Wu, Zhenlong; Hang, Suqin; Zhu, Weiyun; Wu, Guoyao

2015-05-01

Reproduction is vital for producing offspring and preserving genetic resources. However, incidences of many reproductive disorders (e.g. miscarriage, intrauterine growth restriction, premature delivery and lower sperm quality) have either increased dramatically or remained at high rates over the last decades. Mounting evidence shows a strong correlation between enteral protein nutrition and reproduction. Besides serving as major nutrients in the diet, amino acids (AA) are signaling molecules in the regulation of diverse physiological processes, ranging from spermatogenesis to oocyte fertilization and to embryo implantation. Notably, the numbers of bacteria in the intestine exceed the numbers of host cells by 10 times. Microbes in the small-intestinal lumen actively metabolize large amounts of dietary AA and, therefore, affect the entry of AA into the portal circulation for whole-body utilization. Changes in the composition and abundance of AA-metabolizing bacteria in the gut during pregnancy, as well as their translocation to the uterus, may alter uterine function and epigenetic modifications of maternal physiology and metabolism, which are crucial for pregnancy recognition and fetal development. Thus, the presence of the maternal gut microbiota and AA metabolites in the intrauterine environments (e.g. endometrium and placenta) and breast milk is likely a unique signature for the programming of the whole-body microbiome and metabolism in both the fetus and infant. Dietary intervention with functional AA, probiotics and prebiotics to alter the abundance and activity of intestinal bacteria may ameliorate or prevent the development of metabolic syndrome, while improving reproductive performance in both males and females as well as their offspring. © The Author 2015. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Distinct Functional Networks Associated with Improvement of Affective Symptoms and Cognitive Function During Citalopram Treatment in Geriatric Depression

PubMed Central

Diaconescu, Andreea Oliviana; Kramer, Elisse; Hermann, Carol; Ma, Yilong; Dhawan, Vijay; Chaly, Thomas; Eidelberg, David; McIntosh, Anthony Randal; Smith, Gwenn S.

2010-01-01

Variability in the affective and cognitive symptom response to antidepressant treatment has been observed in geriatric depression. The underlying neural circuitry is poorly understood. The current study evaluated the cerebral glucose metabolic effects of citalopram treatment and applied multivariate, functional connectivity analyses to identify brain networks associated with improvements in affective symptoms and cognitive function. Sixteen geriatric depressed patients underwent resting Positron Emission Tomography (PET) studies of cerebral glucose metabolism and assessment of affective symptoms and cognitive function before and after eight weeks of selective serotonin reuptake inhibitor treatment (citalopram). Voxel-wise analyses of the normalized glucose metabolic data showed decreased cerebral metabolism during citalopram treatment in the anterior cingulate gyrus, middle temporal gyrus, precuneus, amygdala, and parahippocampal gyrus. Increased metabolism was observed in the putamen, occipital cortex and cerebellum. Functional connectivity analyses revealed two networks which were uniquely associated with improvement of affective symptoms and cognitive function during treatment. A subcortical-limbic-frontal network was associated with improvement in affect (depression and anxiety), while a medial temporal-parietal-frontal network was associated with improvement in cognition (immediate verbal learning/memory and verbal fluency). The regions that comprise the cognitive network overlap with the regions that are affected in Alzheimer’s dementia. Thus, alterations in specific brain networks associated with improvement of affective symptoms and cognitive function are observed during citalopram treatment in geriatric depression. PMID:20886575

The intrauterine environment affects learning ability of Tokai high avoider rat offspring derived using cryopreservation and embryo transfer-mediated reproduction.

PubMed

Endo, Hitoshi; Eto, Tomoo; Yoshii, Fumihito; Owada, Satoshi; Watanabe, Tetsu; Tatemichi, Masayuki; Kimura, Minoru

2017-07-22

Embryo transfer (ET) to recipient female animals is a useful technique in biological and experimental animal studies. While cryopreservation of two-cell stage rat embryos and ET to recipient rats are currently well-defined, it is unknown whether these artificial reproductive techniques and maternal factors affect offspring phenotype, particularly higher brain functions. Therefore, we assessed the effects of cryopreservation, ET, and maternal care on learning behaviour of the offspring, using Tokai high avoider (THA) rats that have a high learning ability phenotype. We found that the high learning ability of THA rat offspring was not replicated following ET to surrogate Wistar rats with a low-avoidance phenotype. Additionally, the characteristic phenotype of offspring obtained through mating of ET-derived rats was similar to that of THA rats. A postnatal cross-fostering investigation with the offspring of Wistar and THA rats showed that maternal behaviour, including postnatal care and lactation traits, did not differ between the dams of low-avoidance Wistar rats and THA rats; therefore, learning behaviour was retained in both Wistar and THA rat offspring. We conclude that the offspring phenotype, although unchanged, has an imperceptible effect on the learning ability of ET-derived THA rats through the intrauterine environment of the recipient. Copyright © 2017 Elsevier Inc. All rights reserved.

Parastar insecticide induced changes in reproductive parameters and testicular oxidative stress biomarkers in Wistar male rats.

PubMed

Nantia, Edouard Akono; Kada, Antoine S; Manfo, Faustin Pt; Tangu, Nehemiah N; Mbifung, Kaghou M; Mbouobda, Desire H; Kenfack, Augustave

2018-07-01

Parastar is an insecticide formulation of lambda-cyhalothrin and imidacloprid, and it is largely used for crop production improvement in Santa, North West Region of Cameroon. This study aimed at evaluating the effects of Parastar on reproductive parameters and testicular oxidative stress in adult albino Wistar male rats. Twenty rats (154 g ± 28 g) were divided into four groups of five animals each and treated daily with either distilled water (10 mL/kg), 1.25, 2.49 or 6.23 mg/kg of Parastar, respectively, for 35 days. After treatment, animal reproductive function was evaluated through fertility tests, sperm characteristics, testosterone levels and organ weights, while oxidative stress biomarkers were determined on testicular homogenates. Parastar administration resulted into increased seminal vesicle and prostate weights, while body weight remained unaffected. Parastar dose-dependently reduced sperm density and mobility, and the highest dose decreased serum testosterone levels. Parastar also modulated stress biomarkers with increased thiobarbituric acid reactive substances levels, decreased glutathione levels and inhibition of catalase and superoxide dismutase activities. In conclusion, Parastar negatively affected male reproductive function through alteration of testosterone levels, sperm parameters and induction of oxidative stress in rats.

Variable mycorrhizal benefits on the reproductive output of Geranium sylvaticum, with special emphasis on the intermediate phenotype.

PubMed

Varga, S; Kytöviita, M-M

2014-03-01

In several gynodioecious species, intermediate sex between female and hermaphrodite has been reported, but few studies have investigated fitness parameters of this intermediate phenotype. Here, we examined the interactions between plant sex and arbuscular mycorrhizal (AM) fungal species affecting the reproductive output of Geranium sylvaticum, a sexually polymorphic plant species with frequent intermediate sexes between females and hermaphrodites, using a common garden experiment. Flowering phenology, AM colonisation levels and several plant vegetative and reproductive parameters, including seed and pollen production, were measured. Differences among sexes were detected in flowering, fruit set, pollen production and floral size. The two AM species used in the present work had different effects on plant fitness parameters. One AM species increased female fitness through increasing seed number and seed mass, while the other species reduced seed mass in all sexes investigated. AM fungi did not affect intermediate and hermaphrodite pollen content in anthers. The three sexes in G. sylvaticum did not differ in their reproductive output in terms of total seed production, but hermaphrodites had potentially larger fathering ability than intermediates due to higher anther number. The ultimate female function--seed production--did not differ among the sexes, but one of the AM fungi used potentially decreased host plant fitness. In addition, in the intermediate sex, mycorrhizal symbiosis functioned similarly in females as in hermaphrodites. © 2013 German Botanical Society and The Royal Botanical Society of the Netherlands.

The cerebellum: its role in language and related cognitive and affective functions.

PubMed

De Smet, Hyo Jung; Paquier, Philippe; Verhoeven, Jo; Mariën, Peter

2013-12-01

The traditional view on the cerebellum as the sole coordinator of motor function has been substantially redefined during the past decades. Neuroanatomical, neuroimaging and clinical studies have extended the role of the cerebellum to the modulation of cognitive and affective processing. Neuroanatomical studies have demonstrated cerebellar connectivity with the supratentorial association areas involved in higher cognitive and affective functioning, while functional neuroimaging and clinical studies have provided evidence of cerebellar involvement in a variety of cognitive and affective tasks. This paper reviews the recently acknowledged role of the cerebellum in linguistic and related cognitive and behavioral-affective functions. In addition, typical cerebellar syndromes such as the cerebellar cognitive affective syndrome (CCAS) and the posterior fossa syndrome (PFS) will be briefly discussed and the current hypotheses dealing with the presumed neurobiological mechanisms underlying the linguistic, cognitive and affective modulatory role of the cerebellum will be reviewed. Copyright © 2012 Elsevier Inc. All rights reserved.

FT Duplication Coordinates Reproductive and Vegetative Growth

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hsu, Chuan-Yu; Adams, Joshua P.; Kim, Hyejin

2011-01-01

Annual plants grow vegetatively at early developmental stages and then transition to the reproductive stage, followed by senescence in the same year. In contrast, after successive years of vegetative growth at early ages, woody perennial shoot meristems begin repeated transitions between vegetative and reproductive growth at sexual maturity. However, it is unknown how these repeated transitions occur without a developmental conflict between vegetative and reproductive growth. We report that functionally diverged paralogs FLOWERING LOCUS T1 (FT1) and FLOWERING LOCUS T2 (FT2), products of whole-genome duplication and homologs of Arabidopsis thaliana gene FLOWERING LOCUS T (FT), coordinate the repeated cycles ofmore » vegetative and reproductive growth in woody perennial poplar (Populus spp.). Our manipulative physiological and genetic experiments coupled with field studies, expression profiling, and network analysis reveal that reproductive onset is determined by FT1 in response to winter temperatures, whereas vegetative growth and inhibition of bud set are promoted by FT2 in response to warm temperatures and long days in the growing season. The basis for functional differentiation between FT1 and FT2 appears to be expression pattern shifts, changes in proteins, and divergence in gene regulatory networks. Thus, temporal separation of reproductive onset and vegetative growth into different seasons via FT1 and FT2 provides seasonality and demonstrates the evolution of a complex perennial adaptive trait after genome duplication.« less

Impact of endocrine disrupting chemicals on onset and development of female reproductive disorders and hormone-related cancer.

PubMed

Scsukova, Sona; Rollerova, Eva; Bujnakova Mlynarcikova, Alzbeta

2016-12-01

A growing body of evidence suggests that exposure to chemical substances designated as endocrine disrupting chemicals (EDCs) due to their ability to disturb endocrine (hormonal) activity in humans and animals, may contribute to problems with fertility, pregnancy, and other aspects of reproduction. The presence of EDCs has already been associated with reproductive malfunction in wildlife species, but it remains difficult to prove causal relationships between the presence of EDCs and specific reproductive problems in vivo, especially in females. On the other hand, the increasing number of experiments with laboratory animals and in vitro research indicate the ability of different EDCs to influence the normal function of female reproductive system, and even their association with cancer development or progression. Research shows that EDCs may pose the greatest risk during prenatal and early postnatal development when organ and neural systems are forming. In this review article, we aim to point out a possible contribution of EDCs to the onset and development of female reproductive disorders and endocrine-related cancers with regard to the period of exposure to EDCs and affected endpoints (organs or processes). Copyright © 2016. Published by Elsevier Urban & Partner Sp. z o.o.

Affect integration and reflective function: clarification of central conceptual issues.

PubMed

Solbakken, Ole André; Hansen, Roger Sandvik; Monsen, Jon Trygve

2011-07-01

The importance of affect regulation, modulation or integration for higher-order reflection and adequate functioning is increasingly emphasized across different therapeutic approaches and theories of change. These processes are probably central to any psychotherapeutic endeavor, whether explicitly conceptualized or not, and in recent years a number of therapeutic approaches have been developed that explicitly target them as a primary area of change. However, there still is important lack of clarity in the field regarding the understanding and operationalization of affect integration, particularly when it comes to specifying underlying mechanisms, the significance of different affect states, and the establishment of operational criteria for measurement. The conceptual relationship between affect integration and reflective function thus remains ambiguous. The present article addresses these topics, indicating ways in which a more complex and exhaustive understanding of integration of affect, cognition and behavior can be attained.

Voluntary exercise at the expense of reproductive success in Djungarian hamsters ( Phodopus sungorus)

NASA Astrophysics Data System (ADS)

Petri, Ines; Scherbarth, Frank; Steinlechner, Stephan

2010-09-01

Energy demands of gestation and lactation represent a severe challenge for small mammals. Therefore, additional energetic burdens may compromise successful breeding. In small rodents, food restriction, cold exposure (also in combination) and wheel running to obtain food have been shown to diminish reproductive outcome. Although exhibited responses such as lower incidence of pregnancy, extended lactation periods and maternal infanticide were species dependent, their common function is to adjust energetic costs to the metabolic state reflecting the trade-off between maternal investment and self-maintenance. In the present study, we sought to examine whether voluntary exercise affects reproduction in Djungarian hamsters ( Phodopus sungorus), which are known for their high motivation to run in a wheel. Voluntary exercise resulted in two different effects on reproduction; in addition to increased infanticide and cannibalism, which was evident across all experiments, the results of one experiment provided evidence that free access to a running wheel may prevent successful pregnancy. It seems likely that the impact of voluntary wheel running on reproduction was associated with a reduction of internal energy resources evoked by extensive exercise. Since the hamsters were neither food-restricted nor forced to run in the present study, an energetic deficit as reason for infanticide in exercising dams would emphasise the particularly high motivation to run in a wheel.

Kisspeptin and energy balance in reproduction.

PubMed

De Bond, Julie-Ann P; Smith, Jeremy T

2014-03-01

Kisspeptin is vital for the neuroendocrine regulation of GNRH secretion. Kisspeptin neurons are now recognized as a central pathway responsible for conveying key homeostatic information to GNRH neurons. This pathway is likely to mediate the well-established link between energy balance and reproductive function. Thus, in states of severely altered energy balance (either negative or positive), fertility is compromised, as is Kiss1 expression in the arcuate nucleus. A number of metabolic modulators have been proposed as regulators of kisspeptin neurons including leptin, ghrelin, pro-opiomelanocortin (POMC), and neuropeptide Y (NPY). Whether these regulate kisspeptin neurons directly or indirectly will be discussed. Moreover, whether the stimulatory role of leptin on reproduction is mediated by kisspeptin directly will be questioned. Furthermore, in addition to being expressed in GNRH neurons, the kisspeptin receptor (Kiss1r) is also expressed in other areas of the brain, as well as in the periphery, suggesting alternative roles for kisspeptin signaling outside of reproduction. Interestingly, kisspeptin neurons are anatomically linked to, and can directly excite, anorexigenic POMC neurons and indirectly inhibit orexigenic NPY neurons. Thus, kisspeptin may have a direct role in regulating energy balance. Although data from Kiss1r knockout and WT mice found no differences in body weight, recent data indicate that kisspeptin may still play a role in food intake and glucose homeostasis. Thus, in addition to regulating reproduction, and mediating the effect of energy balance on reproductive function, kisspeptin signaling may also be a direct regulator of metabolism.

Thyroid hormones and female reproduction.

PubMed

Silva, Juneo F; Ocarino, Natália M; Serakides, Rogéria

2018-05-14

Thyroid hormones are vital for the proper functioning of the female reproductive system, since they modulate the metabolism and development of ovarian, uterine and placental tissues. Therefore, hypo- and hyperthyroidism may result in subfertility or infertility in both women and animals. Other well-documented sequelae of maternal thyroid dysfunctions include menstrual/estral irregularity, anovulation, abortion, preterm delivery, preeclampsia, intrauterine growth restriction, postpartum thyroiditis, and mental retardation in children. Several studies have been carried out involving prospective and retrospective studies of women with thyroid dysfunction, as well as in vivo and in vitro assays of hypo- and hyperthyroidism using experimental animal models and/or ovarian, uterine and placental cell culture. These studies have sought to elucidate the mechanisms by which thyroid hormones influence reproduction to better understand the physiology of the reproductive system and to provide better therapeutic tools for reproductive dysfunctions that originate from thyroid dysfunctions. Therefore, this review aims to summarize and update the available information related to the role of thyroid hormones in the morphophysiology of the ovary, uterus and placenta in women and animals and the effects of hypo- and hyperthyroidism on the female reproductive system.

Compared with feeding infants breast milk or cow-milk formula, soy formula feeding does not affect subsequent reproductive organ size at 5 years of age

USDA-ARS?s Scientific Manuscript database

Abstract Background: Literature reports suggest that phytochemicals, such as isoflavones found in soybeans, impair reproductive function in animals and raise the possibility that consuming soy infant formula could alter hormonally sensitive organ development in children. Objective: This study compar...

[Human reproduction and environmental risk factors].

PubMed

Petrelli, G; Mantovani, A; Menditto, A

1999-01-01

Environmental pollution is a great cause of concern, in particular, growing attention is being paid to the potential of many chemicals to affect the reproductive system in humans. The key role of prevention and control of reproductive hazards is recognized world-wide. Many chemicals have been shown to impair fertility and/or prenatal and perinatal development in experimental studies. However, a sufficient evidence of an effect on human reproduction is available for some compounds only. The use of biological markers may improve the assessment of exposure to chemicals, contribute to identify mechanisms of action and put into evidence early, reversible, biological effects. Valid biological markers are also needed in epidemiological studies: without reliable data on the level of current and past exposures it is difficult to establish a causal relationship between a pollutant and the occurrence of adverse health effects. A multidisciplinary approach to risk assessment is required. Priorities for interdisciplinary research on environmental chemicals and reproduction include the identification of susceptible population subgroups and risk assessment of exposure to multiple chemicals.

Reproductive performance and gestational effort in relation to dietary fatty acids in guinea pigs.

PubMed

Nemeth, Matthias; Millesi, Eva; Siutz, Carina; Wagner, Karl-Heinz; Quint, Ruth; Wallner, Bernard

2017-01-01

Dietary saturated (SFAs) and polyunsaturated (PUFAs) fatty acids can highly affect reproductive functions by providing additional energy, modulating the biochemical properties of tissues, and hormone secretions. In precocial mammals such as domestic guinea pigs the offspring is born highly developed. Gestation might be the most critical reproductive period in this species and dietary fatty acids may profoundly influence the gestational effort. We therefore determined the hormonal status at conception, the reproductive success, and body mass changes during gestation in guinea pigs maintained on diets high in PUFAs or SFAs, or a control diet. The diets significantly affected the females' plasma fatty acid status at conception, while cortisol and estrogen levels did not differ among groups. SFA females exhibited a significantly lower body mass and litter size, while the individual birth mass of pups did not differ among groups and a general higher pup mortality rate in larger litters was diminished by PUFAs and SFAs. The gestational effort, determined by a mother's body mass gain during gestation, increased with total litter mass, whereas this increase was lowest in SFA and highest in PUFA individuals. The mother's body mass after parturition did not differ among groups and was positively affected by the total litter mass in PUFA females. While SFAs reduce the litter size, but also the gestational effort as a consequence, PUFA supplementation may contribute to an adjustment of energy accumulations to the total litter mass, which may both favor a mother's body condition at parturition and perhaps increase the offspring survival at birth.

Gene Expression Changes Related to Endocrine Function and Decline in Reproduction in Fathead Minnow (Pimephales promelas) after Dietary Methylmercury Exposure

PubMed Central

Klaper, Rebecca; Rees, Christopher B.; Drevnick, Paul; Weber, Daniel; Sandheinrich, Mark; Carvan, Michael J.

2006-01-01

Background Methylmercury (MeHg) is a known neurotoxic agent, but the mechanisms by which MeHg may act on reproductive pathways are relatively unknown. Several studies have indicated potential changes in hormone levels as well as declines in vertebrates with increasing dietary MeHg exposure. Objectives The purpose of this study was to identify alterations in gene expression associated with MeHg exposure, specifically those associated with previously observed changes in reproduction and reproductive biomarkers. Fathead minnows, Pimephales promelas, were fed one of three diets that were similar to documented concentrations of MeHg in the diets of wild invertivorous and piscivorous fish. We used a commercial macroarray in conjunction with quantitative polymerase chain reaction to examine gene expression in fish in relation to exposure to these environmentally relevant doses of MeHg. Results Expression of genes commonly associated with endocrine disruption was altered with Hg exposure. Specifically, we observed a marked up-regulation in vitellogenin mRNA in individual Hg-exposed males and a significant decline in vitellogenin gene expression in female fish with increasing Hg concentrations. Other genes identified by the macroarray experiment included those associated with egg fertilization and development, sugar metabolism, apoptosis, and electron transport. We also observed differences in expression patterns between male and female fish not related to genes specifically associated with reproduction, indicating a potential physiological difference in the reaction of males and females to MeHg. Conclusion Gene expression data may provide insight into the mechanisms by which MeHg affects reproduction in fish and indicate how MeHg differs in its effect from other heavy metals and endocrine-disrupting compounds. PMID:16966085

Effect of hypothyroidism on the hypothalamic-pituitary-ovarian axis and reproductive function of pregnant rats.

PubMed

Sun, Jianran; Hui, Cancan; Xia, Tongjia; Xu, Min; Deng, Datong; Pan, Faming; Wang, Youmin

2018-05-24

This study aimed to detect changes in hormone levels in the hypothalamic-pituitary-ovarian axis in Sprague-Dawley (SD) rats with hypothyroidism, and identify differences in the pregnancy and abortion rates of female adult rats. The potential role of gonadotropin releasing hormone (GnRH) as the link between the hypothalamic-pituitary-ovarian axis and reproductive function regulated by thyroid hormones was also investigated. Female SD rats (n = 136) were causally classified into two groups: the normal-drinking-water group (n = 60) and the 0.05% propylthiouracil-drinking-water group (PTU 2 mg/kg/day, n = 76) to establish an adult rat model of hypothyroidism (6 weeks). Female and male rats at a ratio of 1:2 were used to establish a hypothyroidism pregnancy model. GnRH mRNA and GnRH receptor (GnRHR) expression in rats was detected using real time quantitative PCR(qRT-PCR) and immunohistochemistry, respectively. The abortion rate differed significantly between the hypothyroidism pregnancy group and the normal pregnancy group (P < 0.05). No significant differences were found in the distribution of the GnRHR among the five nuclei (hypothalamic arcuate nucleus, hypothalamic ventromedial nucleus, hypothalamic anterior nucleus, paraventricular nucleus of the hypothalamus, and ventral premammillary nucleus) of the hypothalamus and ovary (P > 0.05). Hypothyroidism had no significant effect on GnRH mRNA expression in the hypothalamic-pituitary-ovarian axis in the four groups (normal control group, normal pregnancy group, hypothyroidism pregnancy group, and hypothyroidism group) (P > 0.05). Hypothyroidism had an adverse impact on pregnancy in rats and may affect the distribution of pituitary GnRHR, whereas it did not obviously affect the distribution of GnRHR in the nuclei of the hypothalamus and ovary. Hypothyroidism had no effect on GnRH mRNA expression.

Oral Contraceptive Use and Reproductive Characteristics Affect Survival in Patients With Epithelial Ovarian Cancer

PubMed Central

Kolomeyevskaya, Nonna V.; Szender, J. Brian; Zirpoli, Gary; Minlikeeva, Albina; Friel, Grace; Cannioto, Rikki A.; Brightwell, Rachel M.; Grzankowski, Kassondra S.; Moysich, Kirsten B.

2015-01-01

Objectives Prognostic risk factors influencing survival in patients with epithelial ovarian cancer (EOC) include tumor stage, grade, histologic subtype, debulking, and platinum status. Little is known about the impact of hormonal milieu and reproductive factors before cancer diagnosis on clinical outcome. We sought to evaluate whether oral contraceptive (OC) use carries any prognostic significance on overall survival (OS) in patients with EOC. Methods Newly diagnosed patients with EOC, fallopian tube, and primary peritoneal cancers between 1982 and 1998 were prospectively evaluated with a comprehensive epidemiologic questionnaire. A retrospective chart review was performed to abstract clinicopathologic data, including OS. A Kaplan-Meier analysis was performed to compare survival across various exposures. A Cox regression model was used to compute adjusted hazards ratios (aHRs) and 95% confidence intervals (CIs). Results We identified 387 newly diagnosed cancers with evaluable information in this cohort. Decreased risk of death was observed in women who reported prior use of OC (aHR, 0.79; 95% CI, 0.58–1.09), previous pregnancy (aHR, 0.77; 95% CI, 0.57–1.04), or a live birth (aHR, 0.81; 95% CI, 0.60–1.08) after adjusting for age at diagnosis, stage, and histologic subtype. Oral contraceptive use was associated with a crude reduced risk of death (HR, 0.55; 95% CI, 0.42–0.72), with reported median OS of 81 months in OC users versus 46 months in nonusers. Patients who reported a single live birth experienced the largest potential survival advantage (aHR, 0.61; 95% CI, 0.39–0.94). Oral contraceptive use and prior pregnancy were associated with improved survival across all strata. Conclusions Oral contraceptive use may have lasting effects on epithelial ovarian tumor characteristics conferring favorable prognosis. Putative mechanisms that affect tumor biology include complex interactions between ovarian cells, host immune cells, and hormonal microenvironment

Abdominally implanted satellite transmitters affect reproduction and survival rather than migration of large shorebirds

USGS Publications Warehouse

Hooijmeijer, Jos C. E. W.; Gill, Robert E.; Mulcahy, Daniel M.; Tibbitts, T. Lee; Kentie, Rosemarie; Gerritsen, Gerrit J.; Bruinzeel, Leo W.; Tijssen, David C.; Harwood, Christopher M.; Piersma, Theunis

2014-01-01

Satellite telemetry has become a common technique to investigate avian life-histories, but whether such tagging will affect fitness is a critical unknown. In this study, we evaluate multi-year effects of implanted transmitters on migratory timing and reproductive performance in shorebirds. Shorebirds increasingly are recognized as good models in ecology and evolution. That many of them are of conservation concern adds to the research responsibilities. In May 2009, we captured 56 female Black-tailed Godwits Limosa limosa limosa during late incubation in The Netherlands. Of these, 15 birds were equipped with 26-g satellite transmitters with a percutaneous antenna (7.8 % ± 0.2 SD of body mass), surgically implanted in the coelom. We compared immediate nest survival, timing of migration, subsequent nest site fidelity and reproductive behaviour including egg laying with those of the remaining birds, a comparison group of 41 females. We found no effects on immediate nest survival. Fledging success and subsequent southward and northward migration patterns of the implanted birds conformed to the expectations, and arrival time on the breeding grounds in 2010–2012 did not differ from the comparison group. Compared with the comparison group, in the year after implantation, implanted birds were equally faithful to the nest site and showed equal territorial behaviour, but a paucity of behaviours indicating nests or clutches. In the 3 years after implantation, the yearly apparent survival of implanted birds was 16 % points lower. Despite intense searching, we found only three eggs of two implanted birds; all were deformed. A similarly deformed egg was reported in a similarly implanted Whimbrel Numenius phaeopus returning to breed in central Alaska. The presence in the body cavity of an object slightly smaller than a normal egg may thus lead to egg malformation and, likely, reduced egg viability. That the use of implanted satellite transmitters in these large shorebirds

Disrupting effects of polychlorinated biphenyls on gonadal development and reproductive functions in chickens.

PubMed

Zhang, Caiqiao; Fang, Changge; Liu, Li; Xia, Guoliang; Qiao, Huili

2002-01-01

Polychlorinated biphenyls (PCBs) are worldwide persistent pollutants that have produced detrimental effects on endocrine function and reproduction in a variety of species. The present study revealed effects of PCBs on gonadal development and functions in chickens of different ages. Aroclor 1254 (0-100 microg/egg) was injected into Hyline chicken eggs before incubation. The adult chickens received Aroclor 1254 by gavage (50 mg/kg BW). It was observed that in day 5 embryos, PCBs resulted in a dose-dependent decrease of primordial germ cell (PGC) numbers, and caused PGCs pyknosis and vacuolation. Clomiphen failed to block the effects of PCBs. In the newly hatched chicken, PCBs induced a marked decrease in area of the transverse sections, diameter and relative area of the testicular tubules. The differentiation of germ cells was retarded after PCB treatment. In contrast, the area of the left ovarian transverse sections, the thickness of ovarian cortex and the number of oocytes increased dramatically in the female chickens after PCB exposure. In the adult chickens, PCBs caused no significant changes in body weight, respiration, heart rate, body temperature, red and white blood cell number, but induced a marked decrease in the testicular weight, and severe damage of the seminiferous tubules. The number of the spermatogenic cells and serum testosterone level were decreased significantly by PCBs. On the contrary, in the laying hens there was no significant effect of PCB on egg quality except a slight decrease in egg weight. These results indicated that PCBs exerted its disrupting effects on chicken reproduction with a sex and stage-related pattern, and in vivo disruption of gonadal development represents a possible model for risk assessment of environmental endocrine disrupters by in ovo treatment.

Reproductive Disorders and Perinatology of Sea Turtles.

PubMed

Spadola, Filippo; Morici, Manuel; Santoro, Mario; Oliveri, Matteo; Insacco, Gianni

2017-05-01

Sea turtles' reproductive disorders are underdiagnosed, but potentially, there are several diseases that may affect gonads, genitalia, and annexes. Viruses, bacteria, and parasites may cause countless disorders, but more frequently the cause is traumatic or linked to human activities. Furthermore, veterinary management of the nest is of paramount importance as well as the care of newborns (also in captivity). This article gives an overview on the methods used to manage nests and reproductive activities of these endangered chelonians species. Copyright © 2016 Elsevier Inc. All rights reserved.

Exposure to phthalates: reproductive outcome and children health. A review of epidemiological studies.

PubMed

Jurewicz, Joanna; Hanke, Wojciech

2011-06-01

Phthalates are a family of industrial chemicals that have been used for a variety of purposes. As the potential consequences of human exposure to phthalates have raised concerns in the general population, they have been studied in susceptible subjects such as pregnant women, infants and children. This article aims at evaluating the impact of exposure to phthalates on reproductive outcomes and children health by reviewing most recent published literature. Epidemiological studies focusing on exposure to phthalates and pregnancy outcome, genital development, semen quality, precocious puberty, thyroid function, respiratory symptoms and neurodevelopment in children for the last ten years were identified by a search of the PubMed, Medline, Ebsco, Agricola and Toxnet literature bases. The results from the presented studies suggest that there are strong and rather consistent indications that phthalates increase the risk of allergy and asthma and have an adverse impact on children's neurodevelopment reflected by quality of alertness among girls, decreased (less masculine) composite score in boys and attention deficit hyperactivity disorder. Results of few studies demonstrate negative associations between phthalate levels commonly experienced by the public and impaired sperm quality (concentration, morphology, motility). Phthalates negatively impact also on gestational age and head circumference; however, the results of the studies were not consistent. In all the reviewed studies, exposure to phthalates adversely affected the level of reproductive hormones (luteinizing hormone, free testosterone, sex hormone-binding globulin), anogenital distance and thyroid function. The urinary levels of phthalates were significantly higher in the pubertal gynecomastia group, in serum in girls with premature thelarche and in girls with precocious puberty. Epidemiological studies, in spite of their limitations, suggest that phthalates may affect reproductive outcome and children health

Life span and reproductive cost explain interspecific variation in the optimal onset of reproduction.

PubMed

Mourocq, Emeline; Bize, Pierre; Bouwhuis, Sandra; Bradley, Russell; Charmantier, Anne; de la Cruz, Carlos; Drobniak, Szymon M; Espie, Richard H M; Herényi, Márton; Hötker, Hermann; Krüger, Oliver; Marzluff, John; Møller, Anders P; Nakagawa, Shinichi; Phillips, Richard A; Radford, Andrew N; Roulin, Alexandre; Török, János; Valencia, Juliana; van de Pol, Martijn; Warkentin, Ian G; Winney, Isabel S; Wood, Andrew G; Griesser, Michael

2016-02-01

Fitness can be profoundly influenced by the age at first reproduction (AFR), but to date the AFR-fitness relationship only has been investigated intraspecifically. Here, we investigated the relationship between AFR and average lifetime reproductive success (LRS) across 34 bird species. We assessed differences in the deviation of the Optimal AFR (i.e., the species-specific AFR associated with the highest LRS) from the age at sexual maturity, considering potential effects of life history as well as social and ecological factors. Most individuals adopted the species-specific Optimal AFR and both the mean and Optimal AFR of species correlated positively with life span. Interspecific deviations of the Optimal AFR were associated with indices reflecting a change in LRS or survival as a function of AFR: a delayed AFR was beneficial in species where early AFR was associated with a decrease in subsequent survival or reproductive output. Overall, our results suggest that a delayed onset of reproduction beyond maturity is an optimal strategy explained by a long life span and costs of early reproduction. By providing the first empirical confirmations of key predictions of life-history theory across species, this study contributes to a better understanding of life-history evolution. © 2016 The Author(s). Evolution © 2016 The Society for the Study of Evolution.

Melanocortin 4 receptor is not required for estrogenic regulations on energy homeostasis and reproduction.

PubMed

Xu, Pingwen; Zhu, Liangru; Saito, Kenji; Yang, Yongjie; Wang, Chunmei; He, Yanlin; Yan, Xiaofeng; Hyseni, Ilirjana; Tong, Qingchun; Xu, Yong

2017-05-01

Brain estrogen receptor-α (ERα) is essential for estrogenic regulation of energy homeostasis and reproduction. We previously showed that ERα expressed by pro-opiomelanocortin (POMC) neurons mediates estrogen's effects on food intake, body weight, negative regulation of hypothalamic-pituitary-gonadal axis (HPG axis) and fertility. We report here that global deletion of a key downstream receptor for POMC peptide, the melanocortin 4 receptor (MC4R), did not affect normal negative feedback regulation of estrogen on the HPG axis, estrous cyclicity and female fertility. Furthermore, loss of the MC4R did not influence estrogenic regulation on food intake and body weight. These results indicate that the MC4R is not required for estrogen's effects on metabolic and reproductive functions. Copyright © 2016 Elsevier Inc. All rights reserved.

Steroids, reproductive endocrine function, and affect. A review.

PubMed

Frye, C A

2009-12-01

Although the effects of estrogen (E2) on mood have been studied for some time, there is controversy over the utility of hormone replacement therapy (HRT). Administration of E2 and/or other steroid hormones (e.g., progestogens, androgens, etc.) may be able to reduce increased anxiety and depression that is present with the onset of menopause. However, some studies indicate that E2 replacement does not significantly improve anxiety and/or depressive symptoms in all postmenopausal subjects. More recent data suggests that the efficacy of HRT could be based on a number of factors, including variety of E2-replacements available, the timing during or after menopause when HRT is initiated, and/or effects of other steroid hormones, such as progestogens and androgens. Notably, little attention has been paid to the possible synergistic effects of E2 that may require progestogens and/or androgens to produce positive outcomes in mood. Additionally, steroid hormones have a number of effects that influence anxiety and depression across the lifespan. As such, dose, timing, and combination of steroid replacement may explain these differences in behavioral outcome. With the increasing peri- to postmenopausal population, many women can expect to live nearly half their lifetime in a postmenopausal state. Therefore, examining these ambiguous findings is of critical importance. This review will focus on a synthesis of the available information regarding findings from animal and human studies in terms of effects of steroid hormones across the lifespan, different HRT options and their subsequent interactions in the brain and/or the hypothalamic-pituitary-adrenal axis, and effects on anxiety and depression.

Reproductive rights approach to reproductive health in developing countries

PubMed Central

Pillai, Vijayan K.; Gupta, Rashmi

2011-01-01

Background Research on reproductive health in developing countries focuses mostly on the role of economic development on various components of reproductive health. Cross-sectional and empirical research studies in particular on the effects of non-economic factors such as reproductive rights remain few and far between. Objective This study investigates the influence of two components of an empowerment strategy, gender equality, and reproductive rights on women's reproductive health in developing countries. The empowerment strategy for improving reproductive health is theoretically situated on a number of background factors such as economic and social development. Design Cross-national socioeconomic and demographic data from a number of international organizations on 142 developing countries are used to test a model of reproductive rights and reproductive health. Results The findings suggest that both economic and democratic development have significant positive effects on levels of gender equality. The level of social development plays a prominent role in promoting reproductive rights. It is found that reproductive rights channel the influences of social structural factors and gender equality on reproductive health. PMID:22184501

Reproductive rights approach to reproductive health in developing countries.

PubMed

Pillai, Vijayan K; Gupta, Rashmi

2011-01-01

Research on reproductive health in developing countries focuses mostly on the role of economic development on various components of reproductive health. Cross-sectional and empirical research studies in particular on the effects of non-economic factors such as reproductive rights remain few and far between. This study investigates the influence of two components of an empowerment strategy, gender equality, and reproductive rights on women's reproductive health in developing countries. The empowerment strategy for improving reproductive health is theoretically situated on a number of background factors such as economic and social development. Cross-national socioeconomic and demographic data from a number of international organizations on 142 developing countries are used to test a model of reproductive rights and reproductive health. The findings suggest that both economic and democratic development have significant positive effects on levels of gender equality. The level of social development plays a prominent role in promoting reproductive rights. It is found that reproductive rights channel the influences of social structural factors and gender equality on reproductive health.

MECHANISMS OF MALE REPRODUCTIVE TOXICITY: BED, BATH AND BEYOND

EPA Science Inventory

Male reproductive function depends upon the integration of a great number of highly complex biological processes and their endocrine support. Therefore it is not surprising that male reproductive health can be impaired by exposures to drugs and environmental toxicants that impact...

[Mechanisms of electromagnetic radiation damaging male reproduction].

PubMed

Xue, Lei; Chen, Hao-Yu; Wang, Shui-Ming

2012-08-01

More and more evidence from over 50 years of researches on the effects of electromagnetic radiation on male reproduction show that a certain dose of electromagnetic radiation obviously damages male reproduction, particularly the structure and function of spermatogenic cells. The mechanisms of the injury may be associated with energy dysmetabolism, lipid peroxidation, abnormal expressions of apoptosis-related genes and proteins, and DNA damage.

Acute exposure to gas-supersaturated water does not affect reproductive success of female adult chinook salmon late in maturation

USGS Publications Warehouse

Gale, William L.; Maule, A.G.; Postera, A.; Peters, M.H.

2004-01-01

At times, total dissolved gas concentrations in the Columbia and Snake rivers have been elevated due to involuntary spill from high spring runoff and voluntary spill used as a method to pass juvenile salmonids over dams. The goal of this project was to determine if acute exposure to total dissolved gas supersaturation (TDGS) affects the reproductive performance of female chinook salmon late in their maturation. During this study, adult female spring chinook salmon were exposed to mean TDGS levels of 114.1 % to 125.5%. We ended exposures at first mortality, or at the appearance of impending death. Based on this criterion, exposures lasted from 10 to 68 h and were inversely related to TDGS. There was no effect of TDGS on pre-spawning mortality or fecundity when comparing treatment fish to experimental controls or the general hatchery population four to six weeks after exposures. Egg quality, based on egg weight and egg diameter, did not differ between treatment and control fish. Fertilization rate and survival to eyed-stage was high (>94%) for all groups. With the exception of Renibacterium salmoninarum (the causative agent of bacterial kidney disease; BKD), no viral or bacterial fish pathogens were isolated from experimental fish. The prevalence (about 45%) and severity of R. salmoninarum did not differ among the groups or the general hatchery population. We conclude that these acute exposures to moderate levels of gas-supersaturated water-perhaps similar to that experienced by immigrating adult salmon as they approach and pass a hydropower dam on the Columbia River-did not affect reproductive success of female chinook salmon late in their maturation. These results are most applicable to summer and fall chinook salmon, which migrate in the summer/fall and spawn shortly after reaching their natal streams. Published in 2004 by John Wiley and Sons, Ltd.

Royal Darwinian Demons: Enforced Changes in Reproductive Efforts Do Not Affect the Life Expectancy of Ant Queens.

PubMed

Schrempf, Alexandra; Giehr, Julia; Röhrl, Ramona; Steigleder, Sarah; Heinze, Jürgen

2017-04-01

One of the central tenets of life-history theory is that organisms cannot simultaneously maximize all fitness components. This results in the fundamental trade-off between reproduction and life span known from numerous animals, including humans. Social insects are a well-known exception to this rule: reproductive queens outlive nonreproductive workers. Here, we take a step forward and show that under identical social and environmental conditions the fecundity-longevity trade-off is absent also within the queen caste. A change in reproduction did not alter life expectancy, and even a strong enforced increase in reproductive efforts did not reduce residual life span. Generally, egg-laying rate and life span were positively correlated. Queens of perennial social insects thus seem to maximize at the same time two fitness parameters that are normally negatively correlated. Even though they are not immortal, they best approach a hypothetical "Darwinian demon" in the animal kingdom.

Reproductive consequences of farmland heterogeneity in little owls (Athene noctua).

PubMed

Michel, Vanja T; Naef-Daenzer, Beat; Keil, Herbert; Grüebler, Martin U

2017-04-01

The amount of high-quality habitat patches, their distribution, and the resource accessibility therein play a key role in regulating habitat effects on reproductive success. Heterogeneous habitats offer non-substitutable resources (e.g. nest sites and food) and substitutable resources (e.g. different types of food) in close proximity, thereby facilitating landscape complementation and supplementation. However, it remains poorly understood how spatial resource separation in homogeneous agricultural landscapes affects reproductive success. To fill this gap, we investigated the relationships between farmland heterogeneity and little owl (Athene noctua) reproductive success, including potential indirect effects of the heterogeneity-dependent home-range size on reproduction. Little owl home-ranges were related to field heterogeneity in summer and to structural heterogeneity in winter. Clutch size was correlated with the amount of food-rich habitat close to the nest irrespective of female home-range size, suggesting importance of landscape complementation. Nestling survival was positively correlated with male home-range size, suggesting importance of landscape supplementation. At the same time, fledgling condition was negatively correlated with male home-range size. We conclude that decreasing farmland heterogeneity constrains population productivity by two processes: increasing separation of food resources from nest or roost sites results in low landscape complementation, and reduction of alternative food resources limits landscape supplementation. Our results suggest that structural heterogeneity affects landscape complementation, whereas the heterogeneity and management of farmland fields affect landscape supplementation. Thus, to what extent a reduction of the heterogeneity within agricultural landscapes results in species-specific habitat degradation depends on the ecological processes (i.e. landscape complementation or supplementation) which are affected.

Occupational exposure associated with reproductive dysfunction.

PubMed

Kumar, Sunil

2004-01-01

Evidence suggestive of harmful effects of occupational exposure on the reproductive system and related outcomes has gradually accumulated in recent decades, and is further compounded by persistent environmental endocrine disruptive chemicals. These chemicals have been found to interfere with the function of the endocrine system, which is responsible for growth, sexual development and many other essential physiological functions. A number of occupations are being reported to be associated with reproductive dysfunction in males as well as in females. Generally, occupations involving the manufacture/or application of some of the persistent chemicals that are not easily degradable as well as bio-accumulative chemicals, occupations involving intensive exposure to heat and radiation, occupations involving the use of toxic solvents as well as toxic fumes are reported to be associated with reproductive dysfunction. Occupational exposure of males to various persistent chemicals have been reported to have male mediated adverse reproductive outcomes in the form of abortion, reduction in fertility etc. with inconclusive or limited evidence. Nevertheless, there is a need for more well designed studies in order to implicate any individual chemical having such effects as in most occupations workers are exposed to raw, intermediate and finished products and there are also several confounding factors associated with lifestyles responsible for reproductive dysfunction. There is an urgent need to look at indiscriminate use of persistent chemicals especially pesticides and persistent organic pollutants (POP's) as these chemicals enter the food chain also and could be potential for exposure during the critical period of development. It is also necessary to impart information, and to educate about the safe use of these chemicals, as a very sensitive reproduction issue is involved with exposure to these chemicals. Occupational exposures often are higher than environmental exposures, so

Nutrition and reproduction in women.

PubMed

2006-01-01

Malnutrition is a major problem in developing countries, and obesity and eating disorders are increasingly common in developing as well as developed countries. The reproductive axis is closely linked to nutritional status, especially undernutrition in the female, and inhibitory pathways involving detectors in the hind brain suppress ovulation in subjects with weight loss. Recovery may occur after minimal reacquisition of weight because energy balance is more important than body fat mass. Anorexia nervosa and bulimia nervosa affect up to 5% of women of reproductive age causing amenorrhoea, infertility and, in those who do conceive, an increased likelihood of miscarriage. Obesity can affect reproduction through fat cell metabolism, steroids and secretion of proteins such as leptin and adiponectin and through changes induced at the level of important homeostatic factors such as pancreatic secretion of insulin, androgen synthesis by the ovary and sex hormone-binding globulin (SHBG) production by the liver. WHO estimates that 9 to 25% of women in developed countries are severely obese, and obese mothers are much more likely to have obese children, especially if they have gestational diabetes. Obesity-associated anovulation may lead to infertility and to a higher risk of miscarriage. Management of anovulation with obesity involves diet and exercise as well as standard approaches to ovulation induction. Many obese women conceive without assistance, but pregnancies in obese women have increased rates of pregnancy-associated hypertension, gestational diabetes, large babies, Cesarean section and perinatal mortality and morbidity. Among contraceptors, the fear of weight gain affects uptake and continuation of hormonal contraceptives, although existing trials indicate that any such effects are small. For all methods of hormonal contraception, weight above 70 kg is associated with increased failure rates.

Does Subacromial Osteolysis Affect Shoulder Function after Clavicle Hook Plating?

PubMed Central

Sun, Siwei; Gan, Minfeng; Sun, Han; Wu, Guizhong; Yang, Huilin; Zhou, Feng

2016-01-01

Purpose. To evaluate whether subacromial osteolysis, one of the major complications of the clavicle hook plate procedure, affects shoulder function. Methods. We had performed a retrospective study of 72 patients diagnosed with a Neer II lateral clavicle fracture or Degree-III acromioclavicular joint dislocation in our hospital from July 2012 to December 2013. All these patients had undergone surgery with clavicle hook plate and were divided into two groups based on the occurrence of subacromial osteolysis. By using the Constant-Murley at the first follow-up visit after plates removal, we evaluated patients' shoulder function to judge if it has been affected by subacromial osteolysis. Results. We have analyzed clinical data for these 72 patients, which shows that there is no significant difference between group A (39 patients) and group B (33 patients) in age, gender, injury types or side, and shoulder function (the Constant-Murley scores are 93.38 ± 3.56 versus 94.24 ± 3.60, P > 0.05). Conclusion. The occurrence of subacromial osteolysis is not rare, and also it does not significantly affect shoulder function. PMID:27034937

Impact of bariatric surgery on female reproduction.

PubMed

Merhi, Zaher O

2009-11-01

To evaluate the current literature on the impact and potential mechanisms of surgical weight loss on female reproduction, with a focus on changes in reproductive hormone profile, fertility status, measures of ovarian reserve, efficacy of oral contraception, sexuality, and pregnancy. Appraisal of articles relevant to surgical weight loss and female reproduction. The altered reproductive hormone profile associated with morbid obesity seems to reverse, either partially or totally, after surgical weight loss. Although bariatric surgery seems to improve fertility status and many of the complications associated with obesity in pregnancy, it may be linked to oral contraceptive failure. Although müllerian-inhibiting substance is a direct measure of ovarian reserve, its level changes with obesity and after surgical weight loss. There is a decrease or no change in the risk of miscarriage after bariatric surgery. An improvement in sexual function may follow dramatic surgical weight reduction; however, the possibility of a detrimental influence afterward can occur. The increasing popularity of bariatric surgery in reproductive-age women calls for greater clinician awareness of its impact on female reproduction.

Growth Hormone and Reproduction: A Review of Endocrine and Autocrine/Paracrine Interactions

PubMed Central

Hull, Kerry L.; Harvey, Steve

2014-01-01

The somatotropic axis, consisting of growth hormone (GH), hepatic insulin-like growth factor I (IGF-I), and assorted releasing factors, regulates growth and body composition. Axiomatically, since optimal body composition enhances reproductive function, general somatic actions of GH modulate reproductive function. A growing body of evidence supports the hypothesis that GH also modulates reproduction directly, exerting both gonadotropin-dependent and gonadotropin-independent actions in both males and females. Moreover, recent studies indicate GH produced within reproductive tissues differs from pituitary GH in terms of secretion and action. Accordingly, GH is increasingly used as a fertility adjunct in males and females, both humans and nonhumans. This review reconsiders reproductive actions of GH in vertebrates in respect to these new conceptual developments. PMID:25580121

Evaluation of a reproductive index to estimate grasshopper sparrow and eastern meadowlark reproductive success

USGS Publications Warehouse

Althoff, Donald P.; Gipson, P.S.; Pontius, J.S.; Japuntich, R.D.

2009-01-01

We compared an index of reproductive success based on breeding behavior to actual nest fates of grasshopper sparrows (Ammodramus savannarum) and eastern meadowlarks (Sturnella magna) on 12 plots (4-ha). Concordance of results between the two methods was 58% for grasshopper sparrows and 42% for eastern meadowlarks on a plot-by-plot basis. The indirect method yielded higher estimates of reproductive activity than nest monitoring for the balance of the plots,. There was little evidence that brown-headed cowbird (Molothrus ater) parasitism influenced the estimates of reproductive success using the indirect method. We concluded that nests and about-to-fledge nestlings were missed during searches on some plots. It may be appropriate to use an indirect method to more efficiently survey territories and/or plots for species with hard-to-find nests or when monitoring large areas. Use of a reproductive index may be appropriate and more time-efficient than nest searching and monitoring for comparing management effects such as burning, grazing, haying, military training, and other localized disturbances that are likely to affect reproductive success of grasshopper sparrows and eastern meadowlarks. However, nest monitoring may be necessary for more precise estimates of productivity necessary for long-term monitoring. Nest monitoring results are also likely to allow for direct comparisons to results from other studies because the index method requires intimate knowledge of the species being evaluated - a factor that could lead to reduced precision because the experience level of technicians relying only on behavioral cues from study-to-study is likely to vary considerably.

Genetic and pharmacological factors that influence reproductive aging in nematodes.

PubMed

Hughes, Stacie E; Evason, Kimberley; Xiong, Chengjie; Kornfeld, Kerry

2007-02-16

Age-related degenerative changes in the reproductive system are an important aspect of aging, because reproductive success is the major determinant of evolutionary fitness. Caenorhabditis elegans is a prominent organism for studies of somatic aging, since many factors that extend adult lifespan have been identified. However, mechanisms that control reproductive aging in nematodes or other animals are not well characterized. To use C. elegans to measure reproductive aging, we analyzed mated hermaphrodites that do not become sperm depleted and monitored the duration and level of progeny production. Mated hermaphrodites display a decline of progeny production that culminates in reproductive cessation before the end of the lifespan, demonstrating that hermaphrodites undergo reproductive aging. To identify factors that influence reproductive aging, we analyzed genetic, environmental, and pharmacological factors that extend lifespan. Dietary restriction and reduced insulin/insulin-like growth factor signaling delayed reproductive aging, indicating that nutritional status and a signaling pathway that responds to environmental stress influence reproductive aging. Cold temperature delayed reproductive aging. The anticonvulsant medicine ethosuximide, which affects neural activity, delayed reproductive aging, indicating that neural activity can influence reproductive aging. Some of these factors decrease early progeny production, but there is no consistent relationship between early progeny production and reproductive aging in strains with an extended lifespan. To directly examine the effects of early progeny production on reproductive aging, we used sperm availability to modulate the level of early reproduction. Early progeny production neither accelerated nor delayed reproductive aging, indicating that reproductive aging is not controlled by use-dependent mechanisms. The implications of these findings for evolutionary theories of aging are discussed.

Does catch and release affect the mating system and individual reproductive success of wild Atlantic salmon (Salmo salar L.)?

PubMed

Richard, Antoine; Dionne, Mélanie; Wang, Jinliang; Bernatchez, Louis

2013-01-01

In this study, we documented the breeding system of a wild population of Atlantic salmon (Salmo salar L.) by genetically sampling every returning adult and assessed the determinants of individual fitness. We then quantified the impacts of catch and release (C&R) on mating and reproductive success. Both sexes showed high variance in individual reproductive success, and the estimated standardized variance was higher for males (2.86) than for females (0.73). We found a weak positive relationship between body size and fitness and observed that fitness was positively correlated with the number of mates, especially in males. Mature male parr sired 44% of the analysed offspring. The impact of C&R on the number of offspring was size dependent, as the reproductive success of larger fish was more impaired than smaller ones. Also, there was an interactive negative effect of water temperature and air exposure time on reproductive success of C&R salmon. This study improves our understanding of the complex reproductive biology of the Atlantic salmon and is the first to investigate the impact of C&R on reproductive success. Our study expands the management toolbox of appropriate C&R practices that promote conservation of salmon populations and limit negative impacts on mating and reproductive success. © 2012 Blackwell Publishing Ltd.

Flower diversity and bee reproduction in an arid ecosystem.

PubMed

Dorado, Jimena; Vázquez, Diego P

2016-01-01

Diverse flower communities are more stable in floral resource production along the flowering season, but the question about how the diversity and stability of resources affect pollinator reproduction remains open. High plant diversity could favor short foraging trips, which in turn would enhance bee fitness. In addition to plant diversity, greater temporal stability of floral resources in diverse communities could favor pollinator fitness because such communities are likely to occupy the phenological space more broadly, increasing floral availability for pollinators throughout the season. In addition, this potential effect of flower diversity on bee reproduction could be stronger for generalist pollinators because they can use a broader floral spectrum. Based on above arguments we predicted that pollinator reproduction would be positively correlated to flower diversity, and to temporal stability in flower production, and that this relationship would be stronger for the most generalized pollinator species. Using structural equation models, we evaluated the effect of these variables and other ecological factors on three estimates of bee reproduction (average number of brood cells per nest per site, total number of brood cells per site, and total number of nests per site), and whether such effects were modulated by bee generalization on floral resources. Contrary to our expectations, flower diversity had no effect on bee reproduction, stability in flower production had a weakly negative effect on one of the bee reproductive variables, and the strength of the fitness-diversity relationship was unrelated to bee generalization. In contrast, elevation had a negative effect on bee reproduction, despite the narrow elevation range encompassed by our sites. Flower diversity did not affect the reproduction of the solitary bees studied here. This result could stem from the context dependence of the diversity-stability relationship, given that elevation had a positive effect on

Flower diversity and bee reproduction in an arid ecosystem

PubMed Central

Vázquez, Diego P.

2016-01-01

Background: Diverse flower communities are more stable in floral resource production along the flowering season, but the question about how the diversity and stability of resources affect pollinator reproduction remains open. High plant diversity could favor short foraging trips, which in turn would enhance bee fitness. In addition to plant diversity, greater temporal stability of floral resources in diverse communities could favor pollinator fitness because such communities are likely to occupy the phenological space more broadly, increasing floral availability for pollinators throughout the season. In addition, this potential effect of flower diversity on bee reproduction could be stronger for generalist pollinators because they can use a broader floral spectrum. Based on above arguments we predicted that pollinator reproduction would be positively correlated to flower diversity, and to temporal stability in flower production, and that this relationship would be stronger for the most generalized pollinator species. Materials and Methods: Using structural equation models, we evaluated the effect of these variables and other ecological factors on three estimates of bee reproduction (average number of brood cells per nest per site, total number of brood cells per site, and total number of nests per site), and whether such effects were modulated by bee generalization on floral resources. Results: Contrary to our expectations, flower diversity had no effect on bee reproduction, stability in flower production had a weakly negative effect on one of the bee reproductive variables, and the strength of the fitness-diversity relationship was unrelated to bee generalization. In contrast, elevation had a negative effect on bee reproduction, despite the narrow elevation range encompassed by our sites. Discussion: Flower diversity did not affect the reproduction of the solitary bees studied here. This result could stem from the context dependence of the diversity

Agonistic reciprocity is associated with reduced male reproductive success within haremic social networks

PubMed Central

Solomon-Lane, Tessa K.; Pradhan, Devaleena S.; Willis, Madelyne C.; Grober, Matthew S.

2015-01-01

While individual variation in social behaviour is ubiquitous and causes social groups to differ in structure, how these structural differences affect fitness remains largely unknown. We used social network analysis of replicate bluebanded goby (Lythrypnus dalli) harems to identify the reproductive correlates of social network structure. In stable groups, we quantified agonistic behaviour, reproduction and steroid hormones, which can both affect and respond to social/reproductive cues. We identified distinct, optimal social structures associated with different reproductive measures. Male hatching success (HS) was negatively associated with agonistic reciprocity, a network structure that describes whether subordinates ‘reciprocated’ agonism received from dominants. Egg laying was associated with the individual network positions of the male and dominant female. Thus, males face a trade-off between promoting structures that facilitate egg laying versus HS. Whether this reproductive conflict is avoidable remains to be determined. We also identified different social and/or reproductive roles for 11-ketotestosterone, 17β-oestradiol and cortisol, suggesting that specific neuroendocrine mechanisms may underlie connections between network structure and fitness. This is one of the first investigations of the reproductive and neuroendocrine correlates of social behaviour and network structure in replicate, naturalistic social groups and supports network structure as an important target for natural selection. PMID:26156769

The Effect of Latitudinal Variation on Shrimp Reproductive Strategies.

PubMed

van de Kerk, Madelon; Jones Littles, Chanda; Saucedo, Omar; Lorenzen, Kai

2016-01-01

Reproductive strategies comprise the timing and frequency of reproductive events and the number of offspring per reproductive event, depending on factors such as climate conditions. Therefore, species that exhibit plasticity in the allocation of reproductive effort can alter their behavior in response to climate change. Studying how the reproductive strategy of species varies along the latitudinal gradient can help us understand and predict how they will respond to climate change. We investigated the effects of the temporal allocation of reproductive effort on the population size of brown shrimp (Farfantepenaeus aztecus) along a latitudinal gradient. Multiple shrimp species exhibit variation in their reproductive strategies, and given the economic importance of brown shrimp to the commercial fishing sector of the Unites States, changes in the timing of their reproduction could have significant economic and social consequences. We used a stage-based, density-dependent matrix population model tailored to the life history of brown shrimp. Shrimp growth rates and environmental carrying capacity were varied based on the seasonal climate conditions at different latitudes, and we estimated the population size at equilibrium. The length of the growing season increased with decreasing latitude and the reproductive strategy leading to the highest population size changed from one annual birth pulse with high reproductive output to continuous low-output reproduction. Hence, our model confirms the classical paradigm of continuous reproduction at low latitudes, with increased seasonality of the breeding period towards the poles. Our results also demonstrate the potential for variation in climate to affect the optimal reproductive strategy for achieving maximum population sizes. Certainly, understanding these dynamics may inform more comprehensive management strategies for commercially important species like brown shrimp.

High basal metabolic rate does not elevate oxidative stress during reproduction in laboratory mice.

PubMed

Brzęk, Paweł; Książek, Aneta; Ołdakowski, Łukasz; Konarzewski, Marek

2014-05-01

Increased oxidative stress (OS) has been suggested as a physiological cost of reproduction. However, previous studies reported ambiguous results, with some even showing a reduction of oxidative damage during reproduction. We tested whether the link between reproduction and OS is mediated by basal metabolic rate (BMR), which has been hypothesized to affect both the rate of radical oxygen species production and antioxidative capacity. We studied the effect of reproduction on OS in females of laboratory mice divergently selected for high (H-BMR) and low (L-BMR) BMR, previously shown to differ with respect to parental investment. Non-reproducing L-BMR females showed higher oxidative damage to lipids (quantified as the level of malondialdehyde in internal organ tissues) and DNA (quantified as the level of 8-oxodG in blood serum) than H-BMR females. Reproduction did not affect oxidative damage to lipids in either line; however, it reduced damage to DNA in L-BMR females. Reproduction increased catalase activity in liver (significantly stronger in L-BMR females) and decreased it in kidneys. We conclude that the effect of reproduction on OS depends on the initial variation in BMR and varies between studied internal organs and markers of OS.

Environmental release of chemicals and reproductive ecology.

PubMed Central

Bajaj, J S; Misra, A; Rajalakshmi, M; Madan, R

1993-01-01

Reproductive ecology is defined as "the study of causes and mechanisms of the effects of environmental risk factors on reproductive health and the methods of their prevention and management." Major areas of concern, within the purview of this paper, relate to adverse pregnancy outcomes, effects on target tissues in the male and the female, and alterations in the control and regulatory mechanisms of reproductive processes. Teratogenic potential of chemicals, released as a result of accidents and catastrophes, is of critical significance. Congenital Minamata disease is due to transplacental fetal toxicity caused by accidental ingestion of methyl mercury. Generalized disorders of ectodermal tissue following prenatal exposure to polychlorinated biphenyls have been reported in Taiwan and Japan. The Bhopal gas disaster, a catastrophic industrial accident, was due to a leak of toxic gas, methyl isocyanate (MIC), in the pesticide manufacturing process. The outcome of pregnancy was studied in female survivors of MIC exposure. The spontaneous abortion rate was nearly four times more common in the affected areas as compared to the control area (24.2% versus 5.6%; p < 0.0001). Furthermore, while stillbirth rate was found to be similar in the affected and control areas, the perinatal and neonatal mortality rates were observed to be higher in the affected area. The rate of congenital malformations in the affected and control areas did not show any significant difference. Chromosomal aberrations and sister chromatid exchange (SCE) frequencies were investigated in human survivors of exposure. The observed SCE frequencies in control and exposed groups indicated that mutagenesis has been induced. Strategies for the management, prediction, and preventability of such disasters are outlined. PMID:8243381

ACCUMULATION AND EFFECTS OF PFOS ON THE REPRODUCTIVE ENDOCRINOLOGY OF THE FATHEAD MINNOW

EPA Science Inventory

Perfluorooctane sulfonate (PFOS) is a globally-distributed contaminant in fish and wildlife. Comparatively little is known, however, concerning potential adverse effects of PFOS on reproduction and development of fish. There is some indication that PFOS could affect reproductive ...

Llama reproduction.

PubMed

Johnson, L W

1989-03-01

The reproductive anatomy, physiology, and breeding behavior of the llama is unique enough to make familiarity with it imperative. Female puberty averages 12 months, while many males are not reproductively functional until after 3 years. Proper management of a breeding pair or herd is necessary to maintain maximum reproductive performance. Proof of pregnancy is suggested by rejection of the male and may/should be confirmed by progesterone assay, rectal palpation, or ultrasound techniques. The postpartum female is notable for breeding back rapidly, with high pregnancy rates resulting. Both male and female factors enter into llama infertility, with each gender having significant incidence of reproductive anatomical abnormalities. Management as well as acquired infertility problems (heat factors, trauma, infection, neoplasia, and hormonal imbalances) contribute to the bulk of infertility cases investigated. Techniques used to diagnose infertility in llamas are quite comparable to the equine species; however, female body size and semen analysis in the male present significant challenges. The approach to therapy has been quite empirical to date, owing to lack of consistent problems and numbers to afford conclusive trials. Alterations of pregnancy include resorption, abortions, and stillbirths. Resorption between 30 to 60 days of gestation is reported regularly. Abortions caused by stress occur regularly. Infection abortions caused by leptospirosis, toxoplasmosis, and chlamydiosis are to be expected. Ponderosa pine-related abortions are suspected. In summary, I find use for a broad background in large animal theriogenology to apply to llama infertility. There no doubt are additional diagnostic techniques and therapeutic regimens that have application, and it is up to us all to keep good records and share the information.

Role of oxidative stress in female reproduction