Mowry, Annelise V; Kavazis, Andreas N; Sirman, Aubrey E; Potts, Wayne K; Hood, Wendy R
2016-01-01
Reproduction is thought to come at a cost to longevity. Based on the assumption that increased energy expenditure during reproduction is associated with increased free-radical production by mitochondria, oxidative damage has been suggested to drive this trade-off. We examined the impact of reproduction on liver mitochondrial function by utilizing post-reproductive and non-reproductive house mice (Mus musculus) living under semi-natural conditions. The age-matched post-reproductive and non-reproductive groups were compared after the reproductive females returned to a non-reproductive state, so that both groups were in the same physiological state at the time the liver was collected. Despite increased oxidative damage (p = 0.05) and elevated CuZnSOD (p = 0.002) and catalase (p = 0.04) protein levels, reproduction had no negative impacts on the respiratory function of liver mitochondria. Specifically, in a post-reproductive, maintenance state the mitochondrial coupling (i.e., respiratory control ratio) of mouse livers show no negative impacts of reproduction. In fact, there was a trend (p = 0.059) to suggest increased maximal oxygen consumption by liver mitochondria during the ADP stimulated state (i.e., state 3) in post-reproduction. These findings suggest that oxidative damage may not impair mitochondrial respiratory function and question the role of mitochondria in the trade-off between reproduction and longevity. In addition, the findings highlight the importance of quantifying the respiratory function of mitochondria in addition to measuring oxidative damage.
Insulin: its Role in the Central Control of Reproduction
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
Insulin: its role in the central control of reproduction.
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 and environmental origins of obesity relevant to reproduction.
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.
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.
Environmental exposure and altered menstrual function
DOE Office of Scientific and Technical Information (OSTI.GOV)
Keye, W.R. Jr.
The impact of environmental agents and occupational factors on hypothalamic and pituitary function and menstruation are poorly understood. To date, most research related to environment, occupation, and reproduction has focused on pregnancy outcome, not menstrual function. It is imperative, however, that menstrual function be considered as an outcome variable in the study of reproduction and occupation.
[Impact of cell phone radiation on male reproduction].
Kang, Ning; Shang, Xue-Jun; Huang, Yu-Feng
2010-11-01
With the popularized use cell phones, more and more concern has been aroused over the effects of their radiation on human health, particularly on male reproduction. Cell phone radiation may cause structural and functional injuries of the testis, alteration of semen parameters, reduction of epididymal sperm concentration and decline of male fertility. This article presents an overview on the impact of cell phone radiation on male reproduction.
Impact of Marine Drugs on Animal Reproductive Processes
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
MECHANISMS OF MALE REPRODUCTIVE TOXICITY: BED, BATH AND BEYOND
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...
Design: Reviewed articles indexed in PubMed from 1999-2007 addressing environment and puberty, menstrual and ovarian function, fertility, and menopause. Results: The strongest evidence of environmental contaminant exposures interfering with healthy reproductive function in adu...
Obesity and reproductive function: a review of the evidence.
Klenov, Violet E; Jungheim, Emily S
2014-12-01
Over the last decade, the evidence linking obesity to impaired reproductive function has grown. In this article, we review this evidence and discuss the underlying pathophysiology. Obese women are less likely than normal-weight women to achieve pregnancy. Female obesity adversely affects reproductive function through alterations in the hypothalamic-pituitary-ovarian axis, oocyte quality, and endometrial receptivity. It is unclear which mechanism contributes the most to subfecundity, and it is likely a cumulative process. Emerging data highlight the contribution of male obesity to impaired reproductive function and that couple obesity has synergistic adverse effects. Once pregnant, obese women are at higher risk for adverse pregnancy outcomes. Weight loss improves reproductive potential in obese patients. As obese women surpass 35 years of age, age may be more important than body mass index in determining reproductive potential. Obstetrician gynecologists need to be aware of the negative impact of obesity on reproductive function so that they appropriately counsel their patients. Further work is needed to clarify the underlying pathophysiology responsible for adverse effects of obesity on reproduction so that novel treatment approaches may be developed.
Diabetes mellitus induced impairment of male reproductive functions: a review.
Jangir, Ram Niwas; Jain, Gyan Chand
2014-05-01
Diabetes mellitus (DM) represents one of the greatest threats to human health all over the world. The incidence of DM is rising rapidly also including children and young persons of reproductive age. Diabetes has been associated with reproductive impairment in both men and women. Diabetes may affect male reproductive functions at multiple levels as a result of its effects on the endocrine control of spermatogenesis, steroidogenesis, sperm maturation, impairment of penile erection and ejaculation. A large number of studies both on diabetic men and experimental diabetic animals have been published on the impact of DM on male reproductive functions during the past few years but many of them have conflicting results. The present review summarizes the research finding of a large number of research papers on the reproductive functions especially on hypothalmo-pituitary-gonadal axis, spermatogenesis, histopathology of testis, synthesis and secretion of testosterone, sperm quality, ejaculatory function and fertility both in diabetic men and experimental diabetic animals.
Chapter 22: Female Reproductive Toxicology
The female reproductive system provides multiple targets for environmental toxicants with the hypothalamic-pituitary-ovarian axis. Moreover, the functional impact of a chemical can differ, depending on the species involved and the parameters of exposure. While cross-species compa...
Impact of bariatric surgery on female reproduction.
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.
Reproductive choice in Islam: gender and state in Iran and Tunisia.
Obermeyer, C M
1994-01-01
This report examines the extent to which reproductive choice is compatible with Islamic principles. It presents the argument that the impact of Islam on reproductive choice is largely a function of the political context in which gender issues are defined. Indicators of reproductive health in countries of the Middle East are reviewed and the way these relate to constraints on reproductive choice is assessed. The examples of Tunisia and Iran are used to illustrate the way in which Islam is invoked to legitimate conflicting positions concerning women and their reproductive options.
Prostaglandins and reproduction in female farm animals.
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.
Foetal exposure to phthalates is known to adversely impact male reproductive development and function. Developmental anomalies of reproductive tract have been attributed to impaired testosterone synthesis. However, species differences in the ability to produce testosterone have...
Caloric restriction: Impact upon pituitary function and reproduction
Martin, Bronwen; Golden, Erin; Carlson, Olga D.; Egan, Josephine M.; Mattson, Mark P.; Maudsley, Stuart
2008-01-01
Reduced energy intake, or caloric restriction (CR), is known to extend life span and to retard age-related health decline in a number of different species, including worms, flies, fish, mice and rats. CR has been shown to reduce oxidative stress, improve insulin sensitivity, and alter neuroendocrine responses and central nervous system (CNS) function in animals. CR has particularly profound and complex actions upon reproductive health. At the reductionist level the most crucial physiological function of any organism is its capacity to reproduce. For a successful species to thrive, the balance between available energy (food) and the energy expenditure required for reproduction must be tightly linked. An ability to coordinate energy balance and fecundity involves complex interactions of hormones from both the periphery and the CNS and primarily centers upon the master endocrine gland, the anterior pituitary. In this review article we review the effects of CR on pituitary gonadotrope function and on the male and female reproductive axes. A better understanding of how dietary energy intake affects reproductive axis function and endocrine pulsatility could provide novel strategies for the prevention and management of reproductive dysfunction and its associated comorbidities. PMID:18329344
BRCA Mutations, DNA Repair Deficiency, and Ovarian Aging1
Oktay, Kutluk; Turan, Volkan; Titus, Shiny; Stobezki, Robert; Liu, Lin
2015-01-01
Oocyte aging has a significant impact on reproductive outcomes both quantitatively and qualitatively. However, the molecular mechanisms underlying the age-related decline in reproductive success have not been fully addressed. BRCA is known to be involved in homologous DNA recombination and plays an essential role in double-strand DNA break repair. Given the growing body of laboratory and clinical evidence, we performed a systematic review on the current understanding of the role of DNA repair in human reproduction. We find that BRCA mutations negatively affect ovarian reserve based on convincing evidence from in vitro and in vivo results and prospective studies. Because decline in the function of the intact gene occurs at an earlier age, women with BRCA1 mutations exhibit accelerated ovarian aging, unlike those with BRCA2 mutations. However, because of the still robust function of the intact allele in younger women and because of the masking of most severe cases by prophylactic oophorectomy or cancer, it is less likely one would see an effect of BRCA mutations on fertility until later in reproductive age. The impact of BRCA2 mutations on reproductive function may be less visible because of the delayed decline in the function of normal BRCA2 allele. BRCA1 function and ataxia-telangiectasia-mutated (ATM)-mediated DNA repair may also be important in the pathogenesis of age-induced increase in aneuploidy. BRCA1 is required for meiotic spindle assembly, and cohesion function between sister chromatids is also regulated by ATM family member proteins. Taken together, these findings strongly suggest the implication of BRCA and DNA repair malfunction in ovarian aging. PMID:26224004
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.
[Toxicological characteristics of Ochratoxin A and its impact on male reproduction].
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.
Inhibition of enzymes involved in the synthesis of sex steroids can substantially impact developmental and reproductive processes controlled by the hypothalmic-pituitary-gonadal (HPG) axis. A key steroidogenic enzyme that has received little attention from a toxicological perspec...
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
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.
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 oral contraceptives are positively related to aspects of cognition in later life. PMID:27996108
Bovine temperament impacts immunity, metabolism, and reproduction: A review
USDA-ARS?s Scientific Manuscript database
Temperament, or excitability, is a behavioral trait that has been shown to impact physiology and performance. Temperament in cattle alters the function of the hypothalamic-pituitary-adrenal axis, thereby influencing circulating concentrations of catecholamines and glucocorticoids. The physiological ...
Science and Technology Text Mining: Mexico Core Competencies
2002-01-01
leaf represents germination nutrient comparative recovered juvenile nutritional winter_spring white difficult spring_summer segment requirements eggs... nutritional ) focuses on diets for small shrimp, emphasizing impact on feed consumption, weight increase, and nutrition . Factor 4 (patients, patient...species, Yucatan , dry season, Campeche, feeding, sex, reproduction) focuses on reproductive and feeding habits of species of both sexes as a function
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.
Brain Sex Matters: estrogen in cognition and Alzheimer’s disease
Li, Rena; Cui, Jie; Shen, Yong
2014-01-01
Estrogens are the primary female sex hormones and play important roles in both reproductive and non-reproductive systems. Estrogens can be synthesized in non-reproductive tissues such as liver, heart, muscle, bone and the brain. During the past decade, increasing evidence suggests that brain estrogen can not only be synthesized by neurons, but also by astrocytes. Brain estrogen also works locally at the site of synthesis in paracrine and/or intracrine fashion to maintain important tissue-specific functions. Here, we will focus on the biology of brain estrogen and its impact on cognitive function and Alzheimer’s disease. This comprehensive review provides new insights into brain estrogens by presenting a better understanding of the tissue-specific estrogen effects and their roles in healthy ageing and cognitive function. PMID:24418360
In mammals, the secretion of gonadotropin-releasing hormone (GnRH) from the brain hypothalamic median eminence constitutes the final common path to the pituitary that results in the ovulatory surge of luteinizing hormone (LH). In rodent test species, a growing number of environme...
Modeling adverse environmental impacts on the reproductive system.
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.
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.
Oxidative shielding and the cost of reproduction.
Blount, Jonathan D; Vitikainen, Emma I K; Stott, Iain; Cant, Michael A
2016-05-01
Life-history theory assumes that reproduction and lifespan are constrained by trade-offs which prevent their simultaneous increase. Recently, there has been considerable interest in the possibility that this cost of reproduction is mediated by oxidative stress. However, empirical tests of this theory have yielded equivocal support. We carried out a meta-analysis to examine associations between reproduction and oxidative damage across markers and tissues. We show that oxidative damage is positively associated with reproductive effort across females of various species. Yet paradoxically, categorical comparisons of breeders versus non-breeders reveal that transition to the reproductive state is associated with a step-change reduction in oxidative damage in certain tissues and markers. Developing offspring may be particularly sensitive to harm caused by oxidative damage in mothers. Therefore, such reductions could potentially function to shield reproducing mothers, gametes and developing offspring from oxidative insults that inevitably increase as a consequence of reproductive effort. According to this perspective, we hypothesise that the cost of reproduction is mediated by dual impacts of maternally-derived oxidative damage on mothers and offspring, and that mothers may be selected to diminish such damage. Such oxidative shielding may explain why many existing studies have concluded that reproduction has little or no oxidative cost. Future advance in life-history theory therefore needs to take account of potential transgenerational impacts of the mechanisms underlying life-history trade-offs. © 2015 Cambridge Philosophical Society.
Stress and the HPA Axis: Balancing Homeostasis and Fertility
Whirledge, Shannon
2017-01-01
An organism’s reproductive fitness is sensitive to the environment, integrating cues of resource availability, ecological factors, and hazards within its habitat. Events that challenge the environment of an organism activate the central stress response system, which is primarily mediated by the hypothalamic–pituitary–adrenal (HPA) axis. The regulatory functions of the HPA axis govern the cardiovascular and metabolic system, immune functions, behavior, and reproduction. Activation of the HPA axis by various stressors primarily inhibits reproductive function and is able to alter fetal development, imparting a biological record of stress experienced in utero. Clinical studies and experimental data indicate that stress signaling can mediate these effects through direct actions in the brain, gonads, and embryonic tissues. This review focuses on the mechanisms by which stress activation of the HPA axis impacts fertility and fetal development. PMID:29064426
[Impact of end-stage renal disease and kidney transplantation on the reproductive system].
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.
Male reprotoxicity and endocrine disruption
Campion, Sarah; Catlin, Natasha; Heger, Nicholas; McDonnell, Elizabeth V.; Pacheco, Sara E.; Saffarini, Camelia; Sandrof, Moses A.; Boekelheide, Kim
2013-01-01
Mammalian reproductive tract development is a tightly regulated process that can be disrupted following exposure to drugs, toxicants, endocrine disrupting chemicals or other compounds via alterations to gene and protein expression or epigenetic regulation. Indeed, the impacts of developmental exposure to certain toxicants may not be fully realized until puberty or adulthood when the reproductive tract becomes sexually mature and altered functionality is manifested. Exposures that occur later in life, once development is complete, can also disrupt the intricate hormonal and paracrine interactions responsible for adult functions, such as spermatogenesis. In this chapter, the biology and toxicology of the male reproductive tract is explored, proceeding through the various life stages including in utero development, puberty, adulthood and senescence. Special attention is given to the discussion of endocrine disrupting chemicals, chemical mixtures, low dose effects, transgenerational effects, and potential exposure-related causes of male reproductive tract cancers. PMID:22945574
Emery Thompson, Melissa; Wilson, Michael L; Gobbo, Grace; Muller, Martin N; Pusey, Anne E
2008-11-01
Chimpanzees in Gombe National Park consume fruits of Vitex fischeri during a short annual fruiting season. This fruit species is a member of a genus widely studied for phytoestrogen composition and varied physiological effects. One particularly well-studied species, V. agnus-castus, is noted for its documented effects on female reproductive function, evidenced in increased progesterone levels and consequent regulation of luteal function. We examined reproductive hormone levels in both male and female chimpanzees during a 6-week period of intense V. fischeri consumption. V. fischeri consumption was associated with an abrupt and dramatic increase in urinary progesterone levels of female chimpanzees to levels far exceeding the normal range of variation. Female estrogen levels were not significantly impacted, nor were male testosterone levels. These are some of the first data indicating that phytochemicals in the natural diet of a primate can have significant impacts on the endocrine system, though the fluctuating nature of chimpanzee diet and reproductive function does not allow us to determine whether the effects observed during this short period had a broader positive or negative impact on female fertility. Given the widespread use of various Vitex species by African primates and the as-yet-undescribed phytochemical properties of these species, we predict that our observations may be indicative of a broader phenomenon. Copyright 2008 Wiley-Liss, Inc.
Antidiabetic therapies and male reproductive function: where do we stand?
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.
Woodruff, Tracey J.; Carlson, Alison; Schwartz, Jackie M.; Giudice, Linda C.
2008-01-01
The 2007 Summit on “Environmental Challenges to Reproductive Health and Fertility” convened scientists, health care professionals, community groups, political representatives and the media to hear presentations on the impact of environmental contaminants on reproductive health and fertility and to discuss opportunities to improve health through research, education, communication and policy. Environmental reproductive health focuses on exposures to environmental contaminants, particularly during critical periods of development, and their potential effects on future reproductive health, including conception, fertility, pregnancy, adolescent development and adult health. Approximately 87,000 chemical substances are registered for use in commerce in the US, with ubiquitous human exposures to environmental contaminants in air, water, food and consumer products. Exposures during critical windows of susceptibility may result in adverse effects with lifelong and even intergenerational health impacts. Effects can include impaired development and function of the reproductive tract and permanently altered gene expression, leading to metabolic and hormonal disorders, reduced fertility and fecundity and illnesses such as testicular, prostate, uterine and cervical cancers later in life. This executive summary reviews effects of pre- and post-natal exposures on male and female reproductive health and provides a series of recommendations for advancing the field in the areas of research, policy, health care and community action. PMID:18275883
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 comparable statistical power. In conclusion, andrological methods and epidemiological designs are available for the implementation of valid studies concerned with environmental impact on human testicular function. Occupational sperm studies should probably not be the first choice when the objective is initial screening of environmental impact on fertility but should be implemented when their is a need to corroborate or refuse earlier evidence that specific exposures have impact on testicular function. Images p514-a PMID:8983461
Introduction: circadian rhythm and its disruption: impact on reproductive function.
Casper, Robert F; Gladanac, Bojana
2014-08-01
Almost all forms of life have predictable daily or circadian rhythms in molecular, endocrine, and behavioral functions. In mammals, a central pacemaker located in the suprachiasmatic nuclei coordinates the timing of these rhythms. Daily light exposure that affects the retina of the eye directly influences this area, which is required to align endogenous processes to the appropriate time of day. The present "Views and Reviews" articles discuss the influence of circadian rhythms, especially nightly secretion of melatonin, on reproductive function and parturition. In addition, an examination is made of problems that arise from recurrent circadian rhythm disruption associated with changes in light exposure patterns common to modern day society. Finally, a possible solution to prevent disruptions in circadian phase markers by filtering out short wavelengths from nocturnal light is reviewed. Copyright © 2014 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.
Oligonucleotide microarrays are a powerful tool for unsupervised analysis of chemical impacts on biological systems. However, the lack of well annotated biological pathways for many aquatic organisms, including fish, and the poor power of microarray-based analyses to detect diffe...
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.
Oligonucleotide microarrays and other ‘omics’ approaches are powerful tools for unsupervised analysis of chemical impacts on biological systems. However, the lack of well annotated biological pathways for many aquatic organisms, including fish, and the poor power of microarray-b...
Effect of dystocia on subsequent reproductive performance and functional longevity in Holstein cows.
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.
Physical activity and its effects on reproduction.
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.
Impact of Sex and Menopausal Status on Episodic Memory Circuitry in Early Midlife.
Jacobs, Emily G; Weiss, Blair K; Makris, Nikos; Whitfield-Gabrieli, Sue; Buka, Stephen L; Klibanski, Anne; Goldstein, Jill M
2016-09-28
Cognitive neuroscience of aging studies traditionally target participants age 65 and older. However, epidemiological surveys show that many women report increased forgetfulness earlier in the aging process, as they transition to menopause. In this population-based fMRI study, we stepped back by over a decade to characterize the changes in memory circuitry that occur in early midlife, as a function of sex and women's reproductive stage. Participants (N = 200; age range, 45-55) performed a verbal encoding task during fMRI scanning. Reproductive histories and serologic evaluations were used to determine menopausal status. Results revealed a pronounced impact of reproductive stage on task-evoked hippocampal responses, despite minimal difference in chronological age. Next, we examined the impact of sex and reproductive stage on functional connectivity across task-related brain regions. Postmenopausal women showed enhanced bilateral hippocampal connectivity relative to premenopausal and perimenopausal women. Across women, lower 17β-estradiol concentrations were related to more pronounced alterations in hippocampal connectivity and poorer performance on a subsequent memory retrieval task, strongly implicating sex steroids in the regulation of this circuitry. Finally, subgroup analyses revealed that high-performing postmenopausal women (relative to low and middle performers) exhibited a pattern of brain activity akin to premenopausal women. Together, these findings underscore the importance of considering reproductive stage, not simply chronological age, to identify neuronal and cognitive changes that unfold in the middle decades of life. In keeping with preclinical studies, these human findings suggest that the decline in ovarian estradiol production during menopause plays a significant role in shaping memory circuitry. Maintaining intact memory function with age is one of the greatest public health challenges of our time, and women have an increased risk for memory disorders relative to men later in life. We studied adults early in the aging process, as women transition into menopause, to identify neuronal and cognitive changes that unfold in the middle decades of life. Results demonstrate regional and network-level differences in memory encoding-related activity as a function of women's reproductive stage, independent of chronological age. Analyzing data without regard to sex or menopausal status obscured group differences in circuit-level neural strategies associated with successful memory retrieval. These findings suggest that early changes in memory circuitry are evident decades before the age range traditionally targeted by cognitive neuroscience of aging studies. Copyright © 2016 the authors 0270-6474/16/3610163-11$15.00/0.
Adolescent TBI-induced hypopituitarism causes sexual dysfunction in adult male rats.
Greco, Tiffany; Hovda, David A; Prins, Mayumi L
2015-02-01
Adolescents are at greatest risk for traumatic brain injury (TBI) and repeat TBI (RTBI). TBI-induced hypopituitarism has been documented in both adults and juveniles and despite the necessity of pituitary function for normal physical and brain development, it is still unrecognized and untreated in adolescents following TBI. TBI induced hormonal dysfunction during a critical developmental window has the potential to cause long-term cognitive and behavioral deficits and the topic currently remains unaddressed. The purpose of this study was to determine if four mild TBIs delivered to adolescent male rats disrupts testosterone production and adult behavioral outcomes. Plasma testosterone was quantified from 72 hrs preinjury to 3 months postinjury and pubertal onset, reproductive organ growth, erectile function and reproductive behaviors were assessed at 1 and 2 months postinjury. RTBI resulted in both acute and chronic decreases in testosterone production and delayed onset of puberty. Significant deficits were observed in reproductive organ growth, erectile function and reproductive behaviors in adult rats at both 1 and 2 months postinjury. These data suggest adolescent RTBI-induced hypopituitarism underlies abnormal behavioral changes observed during adulthood. The impact of undiagnosed hypopituitarism following RTBI in adolescence has significance not only for growth and puberty, but also for brain development and neurobehavioral function as adults. © 2014 Wiley Periodicals, Inc.
Reproductive health/family planning and the health of infants, girls and women.
Sadik, N
1997-01-01
The 1994 International Conference on Population and Development developed international consensus amongst health providers, policy makers, and group representing the whole of civil society regarding the concept of reproductive health and its definition. In line with this definition, reproductive health care is defined as the constellation of methods, techniques and services that contribute to reproductive health and well-being by preventing and solving reproductive health problems. Reproductive health care saves lives and prevents significant levels of morbidity through family planning programmes, antenatal, delivery and post-natal services, prevention and management programmes for reproductive tract infections (including sexually transmitted diseases and HIV/AIDS), prevention of abortion and management of its complications, cancers of the reproductive system, and harmful practices that impact on reproductive function. Reproductive health care needs are evident at all stages of the life cycle and account for a greater proportion of disability adjusted life years (DALYS) in girls and women than in boys and men. Reproductive health protects infant health by enabling birth spacing and birth limitation to be practiced through family planning. The prevention and early detection of reproductive tract infections, including sexually transmitted diseases and HIV, through the integration of preventive measures in family planning service delivery not only improves the quality of care provided but is also directly responsible for improvement in survival and health of infants. Addressing harmful practices such as son preference, sex selection, sexual violence and female genital mutilation complements the positive impact of planned and spaced children through family planning services on infant mortality and the reproductive health of young girls and women. They are also in addition to prenatal, delivery and postnatal services, positive determinants of low maternal mortality and morbidity and are integral to the promotion of reproductive health in women of child bearing age. Reproductive tract infections, including sexually transmitted diseases and HIV contribute to significant level of ill-health in women of reproductive age and continue to pose a threat through the menopause which in turn brings with it increasing risk of cancers of the reproductive system.
The effects of oxidative stress on female reproduction: a review
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 reproductive abilities, and will facilitate further explorations of the possible benefits of antioxidants to treat infertility. PMID:22748101
Jacobs, Emily G; Weiss, Blair; Makris, Nikos; Whitfield-Gabrieli, Sue; Buka, Stephen L; Klibanski, Anne; Goldstein, Jill M
2017-05-01
Converging preclinical and human evidence indicates that the decline in ovarian estradiol production during the menopausal transition may play a mechanistic role in the neuronal changes that occur early in the aging process. Here, we present findings from a population-based fMRI study characterizing regional and network-level differences in working memory (WM) circuitry in midlife men and women (N = 142; age range 46-53), as a function of sex and reproductive stage. Reproductive histories and hormonal evaluations were used to determine menopausal status. Participants performed a verbal WM task during fMRI scanning. Results revealed robust differences in task-evoked responses in dorsolateral prefrontal cortex and hippocampus as a function of women's reproductive stage, despite minimal variance in chronological age. Sex differences in regional activity and functional connectivity that were pronounced between men and premenopausal women were diminished for postmenopausal women. Critically, analyzing data without regard to sex or reproductive status obscured group differences in the circuit-level neural strategies associated with successful working memory performance. These findings underscore the importance of reproductive age and hormonal status, over and above chronological age, for understanding sex differences in the aging of memory circuitry. Further, these findings suggest that early changes in working memory circuitry are evident decades before the age range typically targeted in cognitive aging studies. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.
On the estimation of the reproduction number based on misreported epidemic data.
Azmon, Amin; Faes, Christel; Hens, Niel
2014-03-30
Epidemic data often suffer from underreporting and delay in reporting. In this paper, we investigated the impact of delays and underreporting on estimates of reproduction number. We used a thinned version of the epidemic renewal equation to describe the epidemic process while accounting for the underlying reporting system. Assuming a constant reporting parameter, we used different delay patterns to represent the delay structure in our model. Instead of assuming a fixed delay distribution, we estimated the delay parameters while assuming a smooth function for the reproduction number over time. In order to estimate the parameters, we used a Bayesian semiparametric approach with penalized splines, allowing both flexibility and exact inference provided by MCMC. To show the performance of our method, we performed different simulation studies. We conducted sensitivity analyses to investigate the impact of misspecification of the delay pattern and the impact of assuming nonconstant reporting parameters on the estimates of the reproduction numbers. We showed that, whenever available, additional information about time-dependent underreporting can be taken into account. As an application of our method, we analyzed confirmed daily A(H1N1) v2009 cases made publicly available by the World Health Organization for Mexico and the USA. Copyright © 2013 John Wiley & Sons, Ltd.
Does alcohol have any effect on male reproductive function? A review of literature.
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 impact of abnormal autoimmune function on reproduction: maternal and fetal consequences.
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.
Gastric Bypass Surgery but Not Caloric Restriction Improves Reproductive Function in Obese Mice
Frank, Aaron P.; Zechner, Juliet F.; Clegg, Deborah J
2015-01-01
In women, obesity is associated with decrements in reproductive health that are improved with weight loss. Due to the difficulty of maintaining weight loss through lifestyle interventions, surgical interventions have become popular treatments for obesity. We examined how weight loss induced by Roux-en Y gastric bypass surgery (RYGB) or calorie restriction impacted expression of hypothalamic genes related to energy intake and reproduction. RYGB and calorie restriction induced equivalent weight loss; however, expression of the anorexigenic melanocortin pathway decreased only in calorie restricted mice. Serum estradiol concentrations were lower in calorie restricted mice relative to RYGB during proestrous, suggesting that RYGB maintained normal estrous cycling. Thus, effects of RYGB for female mice, and possibly humans, extend beyond weight loss to include enhanced reproductive health. PMID:26667161
The impact of female reproductive function on outcomes after traumatic brain injury.
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.
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. Considering the suggested health effects, more epidemiologic data is urgently needed and, in the meantime, precautionary policies must be implemented.
USDA-ARS?s Scientific Manuscript database
Widespread use of artificial insemination in swine requires millions of doses of boar semen each year. Subfertility of boars remains a major constraint, which can impact the reproductive efficiency of thousands of sows, so a better understanding of testicular function is needed in order to develop m...
Duncan, Francesca E; Derman, Benjamin; Woodruff, Teresa K
2014-05-01
Our success as a field and as individuals in reproductive science and medicine relies on our ability to produce high quality work that has broad visibility and impact. A common metric for assessing such success is the quantity of publications that are published in journals with high impact factors. It is unclear, however, how frequently work related to reproductive science and medicine actually appears in what are considered the highest impact journals. To address this gap in knowledge, we first determined how the field of reproductive biology in general compared to other research areas in terms of composite journal impact factor. Second, using a targeted search approach in the PubMed database, we examined the relationship between a journal's impact factor and the number of reproductive research articles published per journal issue. We found that compared to other major scientific disciplines, our field lacks journals with impact factors above 4. In addition, primary original research articles on reproduction-irrespective of male or female search terms-do not appear often in high impact journals. Instead, there is an increased percentage of secondary reproductive literature in high impact journals compared to topic-specific journals of lower impact. There are likely several explanations for why reproductive science and medicine has low visibility, including the field's small relative size, its lack of a specific disease and associated strong advocacy, and its surrounding social, ethical, and political unease. Nevertheless, there are concrete actions we can take to minimize the role of impact factor in our evaluation while simultaneously increasing influence through global awareness of the importance and need for reproductive research.
Sita, Kumari; Sehgal, Akanksha; HanumanthaRao, Bindumadhava; Nair, Ramakrishnan M.; Vara Prasad, P. V.; Kumar, Shiv; Gaur, Pooran M.; Farooq, Muhammad; Siddique, Kadambot H. M.; Varshney, Rajeev K.; Nayyar, Harsh
2017-01-01
Ambient temperatures are predicted to rise in the future owing to several reasons associated with global climate changes. These temperature increases can result in heat stress- a severe threat to crop production in most countries. Legumes are well-known for their impact on agricultural sustainability as well as their nutritional and health benefits. Heat stress imposes challenges for legume crops and has deleterious effects on the morphology, physiology, and reproductive growth of plants. High-temperature stress at the time of the reproductive stage is becoming a severe limitation for production of grain legumes as their cultivation expands to warmer environments and temperature variability increases due to climate change. The reproductive period is vital in the life cycle of all plants and is susceptible to high-temperature stress as various metabolic processes are adversely impacted during this phase, which reduces crop yield. Food legumes exposed to high-temperature stress during reproduction show flower abortion, pollen and ovule infertility, impaired fertilization, and reduced seed filling, leading to smaller seeds and poor yields. Through various breeding techniques, heat tolerance in major legumes can be enhanced to improve performance in the field. Omics approaches unravel different mechanisms underlying thermotolerance, which is imperative to understand the processes of molecular responses toward high-temperature stress. PMID:29123532
Sita, Kumari; Sehgal, Akanksha; HanumanthaRao, Bindumadhava; Nair, Ramakrishnan M; Vara Prasad, P V; Kumar, Shiv; Gaur, Pooran M; Farooq, Muhammad; Siddique, Kadambot H M; Varshney, Rajeev K; Nayyar, Harsh
2017-01-01
Ambient temperatures are predicted to rise in the future owing to several reasons associated with global climate changes. These temperature increases can result in heat stress- a severe threat to crop production in most countries. Legumes are well-known for their impact on agricultural sustainability as well as their nutritional and health benefits. Heat stress imposes challenges for legume crops and has deleterious effects on the morphology, physiology, and reproductive growth of plants. High-temperature stress at the time of the reproductive stage is becoming a severe limitation for production of grain legumes as their cultivation expands to warmer environments and temperature variability increases due to climate change. The reproductive period is vital in the life cycle of all plants and is susceptible to high-temperature stress as various metabolic processes are adversely impacted during this phase, which reduces crop yield. Food legumes exposed to high-temperature stress during reproduction show flower abortion, pollen and ovule infertility, impaired fertilization, and reduced seed filling, leading to smaller seeds and poor yields. Through various breeding techniques, heat tolerance in major legumes can be enhanced to improve performance in the field. Omics approaches unravel different mechanisms underlying thermotolerance, which is imperative to understand the processes of molecular responses toward high-temperature stress.
Chandran, Divya; Tai, Yu Chuan; Hather, Gregory; Dewdney, Julia; Denoux, Carine; Burgess, Diane G; Ausubel, Frederick M; Speed, Terence P; Wildermuth, Mary C
2009-03-01
Salicylic acid (SA) is a critical mediator of plant innate immunity. It plays an important role in limiting the growth and reproduction of the virulent powdery mildew (PM) Golovinomyces orontii on Arabidopsis (Arabidopsis thaliana). To investigate this later phase of the PM interaction and the role played by SA, we performed replicated global expression profiling for wild-type and SA biosynthetic mutant isochorismate synthase1 (ics1) Arabidopsis from 0 to 7 d after infection. We found that ICS1-impacted genes constitute 3.8% of profiled genes, with known molecular markers of Arabidopsis defense ranked very highly by the multivariate empirical Bayes statistic (T(2) statistic). Functional analyses of T(2)-selected genes identified statistically significant PM-impacted processes, including photosynthesis, cell wall modification, and alkaloid metabolism, that are ICS1 independent. ICS1-impacted processes include redox, vacuolar transport/secretion, and signaling. Our data also support a role for ICS1 (SA) in iron and calcium homeostasis and identify components of SA cross talk with other phytohormones. Through our analysis, 39 novel PM-impacted transcriptional regulators were identified. Insertion mutants in one of these regulators, PUX2 (for plant ubiquitin regulatory X domain-containing protein 2), results in significantly reduced reproduction of the PM in a cell death-independent manner. Although little is known about PUX2, PUX1 acts as a negative regulator of Arabidopsis CDC48, an essential AAA-ATPase chaperone that mediates diverse cellular activities, including homotypic fusion of endoplasmic reticulum and Golgi membranes, endoplasmic reticulum-associated protein degradation, cell cycle progression, and apoptosis. Future work will elucidate the functional role of the novel regulator PUX2 in PM resistance.
Ernest, Sheila R.; Wade, Michael G.; Lalancette, Claudia; Ma, Yi-Qian; Berger, Robert G.; Robaire, Bernard; Hales, Barbara F.
2012-01-01
Brominated flame retardants (BFRs) are incorporated into a wide variety of consumer products, are readily released into home and work environments, and are present in house dust. Studies using animal models have revealed that exposure to polybrominated diphenyl ethers (PBDEs) may impair adult male reproductive function and thyroid hormone physiology. Such studies have generally characterized the outcome of acute or chronic exposure to a single BFR technical mixture or congener but not the impact of environmentally relevant BFR mixtures. We tested whether exposure to the BFRs found in house dust would have an adverse impact on the adult male rat reproductive system and thyroid function. Adult male Sprague Dawley rats were exposed to a complex BFR mixture composed of three commercial brominated diphenyl ethers (52.1% DE-71, 0.4% DE-79, and 44.2% decaBDE-209) and hexabromocyclododecane (3.3%), formulated to mimic the relative congener levels in house dust. BFRs were delivered in the diet at target doses of 0, 0.02, 0.2, 2, or 20 mg/kg/day for 70 days. Compared with controls, males exposed to the highest dose of BFRs displayed a significant increase in the weights of the kidneys and liver, which was accompanied by induction of CYP1A and CYP2B P450 hepatic drug–metabolizing enzymes. BFR exposure did not affect reproductive organ weights, serum testosterone levels, testicular function, or sperm DNA integrity. The highest dose caused thyroid toxicity as indicated by decreased serum thyroxine (T4) and hypertrophy of the thyroid gland epithelium. At lower doses, the thickness of the thyroid gland epithelium was reduced, but no changes in hormone levels (T4 and thyroid-stimulating hormone) were observed. Thus, exposure to BFRs affected liver and thyroid physiology but not male reproductive parameters. PMID:22387749
Gap junction connexins in female reproductive organs: implications for women's reproductive health.
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. CX40, which characterizes the extravillous trophoblast (EVT), supports proliferation of the proximal EVTs while preventing them from differentiating into the invasive pathway. Furthermore, women with recurrent early pregnancy loss as well as those with endometriosis exhibit reduced levels of CX43 in their decidua. The antimalaria drug mefloquine, which blocks gap junction function, is responsible for increased risk of early pregnancy loss and stillbirth, probably due to inhibition of intercellular communication in the decidua or between trophoblast layers followed by an impairment of placental growth. Gap junctions also play a critical role in regulating uterine blood flow, contributing to the adaptive response to pregnancy. Given that reproductive impairment can result from connexin mutations in mice, it is advised that women suffering from somatic disease symptoms associated with connexin gene mutations be additionally tested for impacts on reproductive function. Better knowledge of these essential connexin functions in human female reproductive organs is important for safeguarding women's reproductive health. © 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.
Plant reproduction is altered by simulated herbicide drift to constructed plant communities
Herbicide drift may have unintended impacts on native vegetation, adversely affecting structure and function of plant communities. However, these potential effects have been rarely studied or quantified. To determine potential ecological effects of herbicide drift, we construct...
Ozgur, Kemal; Bulut, Hasan; Berkkanoglu, Murat; Basegmez, Faruk O; Coetzee, Kevin
2018-06-08
In this study, the endometrial developmental and reproductive outcomes of frozen embryo transfers (FETs) which were performed subsequent to miscarriages managed by dilation and curettage (D and C) were investigated. The intracytoplasmic sperm injection (ICSI) blastocyst freeze-all cycles performed between January 2014 and August 2016 were screened for the patients who had undergone their FET (first), miscarriages (>5 < 14 weeks), D and C, and the patients who had undergone their FET (second) (study group; n = 71); and patients who underwent FET (1st), a chemical pregnancy loss (PL) (<5 weeks) and FET (2nd) (reference group; n = 38). The live births (LB; delivery >20 weeks) of FET (2nd) were analysed in two time-interval sub-groups: ≤6 months or >6 months. In the study and reference groups, the median endometrial thickness at the second FET of the ≤6 months sub-groups was found to be significantly reduced. The relative risk for LB was significantly higher (1.65 [0.994-2.723] p = .043) in the >6 months study sub-group, with a lower risk for PL (0.62 [0.268-1.427] p = .329), whereas, there were no significant differences between the reference sub-groups. The management of miscarriage with D and C results in a significant and transient decrease in reproductive function in subsequent FET. Impact Statement What is already known on this subject? Approximately, 15-30% of positive pregnancies in assisted reproductive technology (ART) end in biochemical pregnancy losses (PLs) or miscarriages. Cervical dilation with suction or blunt curettage (D and C), has been the procedure most often used to manage the retained products of conception (RPOC) after miscarriage. Intrauterine surgery has the potential to directly affect reproduction, depending on the endometrial impact. What the results of this study add? The endometrium after D and C surgery may require 6 months to recover normal reproductive function, in terms of both live birth and PL. The extent of the damage to endometrial function is not found to be reflected in the endometrial thickness. What the implications are of these findings for clinical practice and/or further research? Patients who undergo miscarriage after their ART treatment may need to delay further treatment for 6 months to optimise their chances of LB. Alternative miscarriage management procedures need to be investigated; procedures that have lower risks for an adverse reproductive function and allow for shorter time intervals between treatments.
New genes often acquire male-specific functions but rarely become essential in Drosophila.
Kondo, Shu; Vedanayagam, Jeffrey; Mohammed, Jaaved; Eizadshenass, Sogol; Kan, Lijuan; Pang, Nan; Aradhya, Rajaguru; Siepel, Adam; Steinhauer, Josefa; Lai, Eric C
2017-09-15
Relatively little is known about the in vivo functions of newly emerging genes, especially in metazoans. Although prior RNAi studies reported prevalent lethality among young gene knockdowns, our phylogenomic analyses reveal that young Drosophila genes are frequently restricted to the nonessential male reproductive system. We performed large-scale CRISPR/Cas9 mutagenesis of "conserved, essential" and "young, RNAi-lethal" genes and broadly confirmed the lethality of the former but the viability of the latter. Nevertheless, certain young gene mutants exhibit defective spermatogenesis and/or male sterility. Moreover, we detected widespread signatures of positive selection on young male-biased genes. Thus, young genes have a preferential impact on male reproductive system function. © 2017 Kondo et al.; Published by Cold Spring Harbor Laboratory Press.
Cruciani, V; Iovine, C; Thomé, J-P; Joaquim-Justo, C
2016-01-01
Phthalate esters are widespread contaminants that can cause endocrine disruption in vertebrates. Studies showed that molecules with hormonal activities in vertebrates and invertebrates can affect asexual and sexual reproduction in rotifers. We investigated the impact of di-hexylethyl phthalate (DEHP), di-butyl phthalate (DBP) and butylbenzyl phthalate (BBP), on the asexual and sexual reproduction of the freshwater monogonont rotifer Brachionus calyciflorus in order to determine a potential environmental risk for sexual reproduction. We observed that DEHP has no significant impact on both asexual and sexual reproduction up to 2 mg/L. DBP has a positive effect on asexual reproduction at concentrations from 0.05 to 1 mg/L, but depresses it at 2 mg/L. Sexual reproduction is only affected at 2 mg/L and the impact observed is negative. BBP displayed a negative impact on both asexual and sexual reproduction at 1 and 2 mg/L. However we showed that the impacts of BBP on mixis and fertilization rates observed are due to the decrease in population growth rates at these concentrations and not to a direct impact of BBP on the mixis and the fertilization processes. Our results show that sexual reproduction in B. calyciflorus is not more sensitive than asexual reproduction to any of the substances tested which indicates the mode of action of these molecules is related to general toxicity and not to an interference with potential endocrine regulation of sexual reproduction. Comparison of effect concentrations and surface water contamination by phthalate esters suggests these compounds do not constitute a risk for primary consumers in these environments.
Chakrabarti, Jana; Chatterjee, Ratna; Goswami, Sourendrakanta; Chakravarty, Baidyanath; Kabir, Syed Nazrul
2012-05-01
A critical body mass of adipose tissue is essential for the normal development of female reproductive functions. Leptin, an adipocyte-derived hormone encoded by the 'Ob' gene has been proposed as a peripheral signal indicating the adequacy of nutritional status for reproductive functions. It is reported as a direct regulator of gametogenic and steroidogenic potential of ovary. Though leptin is widely present in reproductive tissues, its relationship to reproductive hormones is still poorly understood. Present investigation attempts to explore ovarian response to secretory profile of leptin and its impact on pregnancy outcome in women undergoing controlled ovarian hyperstimulation for in vitro fertilization and embryo transfer (IVF-ET). Patients enrolled for IVF-ET underwent pituitary-ovarian suppression by 'Long Protocol' GnRH-agonist downregulation followed by ovarian stimulation. Sera were procured at different phases of IVF-ET for the assay of estradiol, progesterone, human chorionic gonadotropin, and for leptin. Ovarian follicular fluids were also assayed for leptin. Luteinized granulosa cells were cultured in vitro to evaluate their steroidogenic potential. Statistical analyses were done by student's t-test, ANOVA, and Chi-square tests as applicable. All results were expressed as Mean ± SE. P values < 0.05 were considered significant. Positive correlation was observed between serum and ovarian follicular fluid leptin. A negative correlation was noted between the serum leptin levels and endometrial thickness. Elevated leptin response may exert adverse impacts on pregnancy success during IVF-ET possibly by modulating uterine receptivity.
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.
Hirshfeld-Cytron, Jennifer; Gracia, Clarisa
2011-01-01
Abstract Cancer treatments can be detrimental to fertility; recent literature has focused on the efforts of fertility preservation for this patient population. It should be recognized, however, that several nonmalignant medical conditions and therapeutic interventions could be similarly hazardous to fertility. Some of these nonmalignant diseases and their treatments that can adversely impact the reproductive axis are gastrointestinal diseases, rheumatologic disorders, nonmalignant hematologic conditions, neurologic disorders, renal disorders, gynecologic conditions, and metabolic diseases. Their negative effects on reproductive function are only now being appreciated and include impaired ovarian function, endocrine function, or sexual function and inability to carry a pregnancy to term. Complications and comorbidities associated with certain diseases may limit the success of established fertility preservation options. Recent advances in fertility preservation techniques may provide these patients with new options for childbearing. Here, we review several fertility-threatening conditions and treatments, describe current established and experimental fertility preservation options, and present three initiatives that may help minimize the adverse reproductive effects of these medical conditions and treatments by raising awareness of the issues and options: (1) increase awareness among practitioners about the reproductive consequences of specific diseases and treatments, (2) facilitate referral of patients to fertility-sparing or restorative programs, and (3) provide patient education about the risk of infertility at the time of diagnosis before initiation of treatment. PMID:21827325
Hirshfeld-Cytron, Jennifer; Gracia, Clarisa; Woodruff, Teresa K
2011-10-01
Cancer treatments can be detrimental to fertility; recent literature has focused on the efforts of fertility preservation for this patient population. It should be recognized, however, that several nonmalignant medical conditions and therapeutic interventions could be similarly hazardous to fertility. Some of these nonmalignant diseases and their treatments that can adversely impact the reproductive axis are gastrointestinal diseases, rheumatologic disorders, nonmalignant hematologic conditions, neurologic disorders, renal disorders, gynecologic conditions, and metabolic diseases. Their negative effects on reproductive function are only now being appreciated and include impaired ovarian function, endocrine function, or sexual function and inability to carry a pregnancy to term. Complications and comorbidities associated with certain diseases may limit the success of established fertility preservation options. Recent advances in fertility preservation techniques may provide these patients with new options for childbearing. Here, we review several fertility-threatening conditions and treatments, describe current established and experimental fertility preservation options, and present three initiatives that may help minimize the adverse reproductive effects of these medical conditions and treatments by raising awareness of the issues and options: (1) increase awareness among practitioners about the reproductive consequences of specific diseases and treatments, (2) facilitate referral of patients to fertility-sparing or restorative programs, and (3) provide patient education about the risk of infertility at the time of diagnosis before initiation of treatment.
Lourdais, O; Brischoux, F; DeNardo, D; Shine, R
2004-07-01
In many species the high energetic demands of reproduction induce a negative energy balance, and thus females must rely on tissue catabolism to complete the reproductive process. Previous works have shown that both fat and protein are energy resources during prolonged fasting in vertebrates. While many ecological studies on energy costs of reproduction have focused on variations in fat stores, the impact of protein investment on the female has not been thoroughly investigated. Notably, as there is no specialized storage form for proteins, intense catabolism is likely to entail structural (musculature) loss that may compromise maternal physical performance after reproduction. Measurements on captive rainbow boas ( Epicrates cenchria maurus) confirm that reproducing females undergo significant protein catabolism (as indicated by elevated plasma uric acid levels) and show considerable musculature loss during gestation (as detected by reduced width of the epaxial muscles). Protein mobilization entailed a significant functional loss that was illustrated by decrements in tests of strength and constriction after parturition. In wild situations, such effects are likely to decrease the snakes' ability to forage and apprehend prey. Hence, the time period needed to recover from reproduction can be extended not only because the female must compensate losses of both fat stores and functional muscle, but also because the ability to do so may be compromised. Performance alteration is likely to be of equal or greater importance than reduced energy stores in the physiological mediation of elevated post-reproduction mortality rates and infrequent reproductive bouts (e.g. biannual or triannual), two common ecological traits of female snakes.
Mechanisms linking energy balance and reproduction: impact of prenatal environment.
Rhinehart, Erin M
2016-01-01
The burgeoning field of metabolic reproduction regulation has been gaining momentum due to highly frequent discoveries of new neuroendocrine factors regulating both energy balance and reproduction. Universally throughout the animal kingdom, energy deficits inhibit the reproductive axis, which demonstrates that reproduction is acutely sensitive to fuel availability. Entrainment of reproductive efforts with energy availability is especially critical for females because they expend large amounts of energy on gestation and lactation. Research has identified an assortment of both central and peripheral factors involved in the metabolic regulation of reproduction. From an evolutionary perspective, these mechanisms likely evolved to optimize reproductive fitness in an environment with an unpredictable food supply and regular bouts of famine. To be effective, however, the mechanisms responsible for the metabolic regulation of reproduction must also retain developmental plasticity to allow organisms to adapt their reproductive strategies to their particular niche. In particular, the prenatal environment has emerged as a critical developmental window for programming the mechanisms responsible for the metabolic control of reproduction. This review will discuss the current knowledge about hormonal and molecular mechanisms that entrain reproduction with prevailing energy availability. In addition, it will provide an evolutionary, human life-history framework to assist in the interpretation of findings on gestational programming of the female reproductive function, with a focus on pubertal timing as an example. Future research should aim to shed light on mechanisms underlying the prenatal modulation of the adaptation to an environment with unstable resources in a way that optimizes reproductive fitness.
Giusti, Arnaud; Leprince, Pierre; Mazzucchelli, Gabriel; Thomé, Jean-Pierre; Lagadic, Laurent; Ducrot, Virginie; Joaquim-Justo, Célia
2013-01-01
Many studies have reported perturbations of mollusc reproduction following exposure to low concentrations (ng/L range) of endocrine disrupting chemicals (EDCs). However, the mechanisms of action of these molecules on molluscs are still poorly understood. Investigation of the modifications of protein expression in organisms exposed to chemicals using proteomic methods can provide a broader and more comprehensive understanding of adverse impacts of pollution on organisms than conventional biochemical biomarkers (e.g., heat-shock proteins, metallothioneins, GST, EROD). In this study we have investigated the impacts of four chemicals, which exhibit different endocrine disrupting properties in vertebrates, on the proteome of the hermaphroditic freshwater pulmonate gastropod Lymnaea stagnalis after 21 days of exposure. Testosterone, tributyltin, chlordecone and cyproterone acetate were chosen as tested compounds as they can induce adverse effects on the reproduction of this snail. The 2D-DIGE method was used to identify proteins whose expression was affected by these compounds. In addition to modifying the expression of proteins involved in the structure and function of the cytoskeleton, chemicals had impacts on the expression of proteins involved in the reproduction of L. stagnalis. Exposure to 19.2 µg/L of chlordecone increased the abundance of ovipostatin, a peptide transmitted during mating through seminal fluid, which reduces oviposition in this species. The expression of yolk ferritin, the vitellogenin equivalent in L. stagnalis, was reduced after exposure to 94.2 ng Sn/L of tributyltin. The identification of yolk ferritin and the modification of its expression in snails exposed to chemicals were refined using western blot analysis. Our results showed that the tested compounds influenced the abundance of yolk ferritin in the reproductive organs. Alteration in proteins involved in reproductive pathways (e.g., ovipostatin and yolk ferritin) could constitute relevant evidence of interaction of EDCs with reproductive pathways that are under the control of the endocrine system of L. stagnalis.
Effects of oil on avian reproduction: A review and discussion
Albers, P.H.; Rosie, Don; Barnes, Stephen N.
1983-01-01
Oil pollution is a highly visible form of environmental contamination that affects avian reproduction in a variety of ways. Plumage oiling causes widespread and locally severe mortality of adult birds. Egg oiling can be a serious hazard for bird embryos but only a few field observationons of this have been reported. Oil ingestion seldom kills birds directly but it causes sublethal change~ in the bodily functions and behavior of adults and nestlings. Studies of the effects of oil on avian reproduction have produced varied and, in ingestion studies, sometimes conflicting results because of inconsistent experimental design and the use of different test species and types of oil. Field experimentation with the sublethal effects of ingested oil on avian reproduction has been limited. Simulation modelling of seabird populations has shown that (l) an occasional decrease in survival of breeding adults will have a greater impact on seabird populations than an occasional decrease in reproductive success, and (2) populations of long-lived seabirds with low reproductive potential have great difficulty recovering from high one-time mortality when experiencing even small sustained annual decreases in either natality or breeding adult survival. The impact of oil-related decreases in survival or reproduction will be more noticeable at the local or colony level than at the regional or species level. Immigration, surplus breeders, and possible compensatory changes in natality and mortality resulting from population reductions usually prevent local population reductions from lasting very long (unless the species is rare or at the edge of its range). A study of west European seabird populations indicates that the natural annual mortality of the region greatly exceeds the annual mortality due to plumage oiling; effects of oil ingestion and egg oiling were not measured but were thought to be less than the mortality from plu~age oiling. Oil-related mortality, even if in addition to expected mortality, would not have a detectable impact on regional populations if environmental conditions were favorable (increased natality, decreased mortality) for the birds.
Giusti, Arnaud; Leprince, Pierre; Mazzucchelli, Gabriel; Thomé, Jean-Pierre; Lagadic, Laurent; Ducrot, Virginie; Joaquim-Justo, Célia
2013-01-01
Many studies have reported perturbations of mollusc reproduction following exposure to low concentrations (ng/L range) of endocrine disrupting chemicals (EDCs). However, the mechanisms of action of these molecules on molluscs are still poorly understood. Investigation of the modifications of protein expression in organisms exposed to chemicals using proteomic methods can provide a broader and more comprehensive understanding of adverse impacts of pollution on organisms than conventional biochemical biomarkers (e.g., heat-shock proteins, metallothioneins, GST, EROD). In this study we have investigated the impacts of four chemicals, which exhibit different endocrine disrupting properties in vertebrates, on the proteome of the hermaphroditic freshwater pulmonate gastropod Lymnaea stagnalis after 21 days of exposure. Testosterone, tributyltin, chlordecone and cyproterone acetate were chosen as tested compounds as they can induce adverse effects on the reproduction of this snail. The 2D-DIGE method was used to identify proteins whose expression was affected by these compounds. In addition to modifying the expression of proteins involved in the structure and function of the cytoskeleton, chemicals had impacts on the expression of proteins involved in the reproduction of L. stagnalis. Exposure to 19.2 µg/L of chlordecone increased the abundance of ovipostatin, a peptide transmitted during mating through seminal fluid, which reduces oviposition in this species. The expression of yolk ferritin, the vitellogenin equivalent in L. stagnalis, was reduced after exposure to 94.2 ng Sn/L of tributyltin. The identification of yolk ferritin and the modification of its expression in snails exposed to chemicals were refined using western blot analysis. Our results showed that the tested compounds influenced the abundance of yolk ferritin in the reproductive organs. Alteration in proteins involved in reproductive pathways (e.g., ovipostatin and yolk ferritin) could constitute relevant evidence of interaction of EDCs with reproductive pathways that are under the control of the endocrine system of L. stagnalis. PMID:24363793
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.
Crowder, Camerron M; Meyer, Eli; Fan, Tung-Yung; Weis, Virginia M
2017-08-01
Reproductive timing in brooding corals has been correlated to temperature and lunar irradiance, but the mechanisms by which corals transduce these environmental variables into molecular signals are unknown. To gain insight into these processes, global gene expression profiles in the coral Pocillopora damicornis were examined (via RNA-Seq) across lunar phases and between temperature treatments, during a monthly planulation cycle. The interaction of temperature and lunar day together had the largest influence on gene expression. Mean timing of planulation, which occurred at lunar days 7.4 and 12.5 for 28- and 23°C-treated corals, respectively, was associated with an upregulation of transcripts in individual temperature treatments. Expression profiles of planulation-associated genes were compared between temperature treatments, revealing that elevated temperatures disrupted expression profiles associated with planulation. Gene functions inferred from homologous matches to online databases suggest complex neuropeptide signalling, with calcium as a central mediator, acting through tyrosine kinase and G protein-coupled receptor pathways. This work contributes to our understanding of coral reproductive physiology and the impacts of environmental variables on coral reproductive pathways. © 2017 John Wiley & Sons Ltd.
Depressive Symptoms among Young Breast Cancer Survivors: The Importance of Reproductive Concerns
Gorman, Jessica R; Malcarne, Vanessa L; Roesch, Scott C; Madlensky, Lisa; Pierce, John P
2010-01-01
Purpose Breast cancer diagnosis and treatment can negatively impact fertility in premenopausal women and influence reproductive planning. This study investigates whether concerns about reproduction after breast cancer treatment were associated with long-term depressive symptoms. Patients and Methods Participants include 131 women diagnosed with early-stage breast cancer at age 40 or younger participating in the Women's Healthy Eating and Living (WHEL) Survivorship Study. Participants were enrolled an average of 1.5 years post-diagnosis and depressive symptoms were monitored 6 times throughout the average additional 10 year follow-up period. Detailed recall of reproductive concerns after treatment was collected an average of 12 years post-diagnosis. Multilevel regression was used to evaluate whether mean long-term depressive symptoms differed as a function of reproductive concerns and significant covariates. Results Multilevel regression identified greater recalled reproductive concerns as an independent predictor of consistent depressive symptoms after controlling for both social support and physical health (B= 0.02, SE= 0.01, p=0.04). In bivariate analyses, being nulliparous at diagnosis and reporting treatment-related ovarian damage were both strongly associated with higher reproductive concerns and with depressive symptoms. Conclusion Reported reproductive concerns after breast cancer treatment were a significant contributor to consistent depressive symptoms. Younger survivors would benefit from additional information and support related to reproductive issues. PMID:20130979
NASA Astrophysics Data System (ADS)
Cardeccia, Alice; Marchini, Agnese; Occhipinti-Ambrogi, Anna; Galil, Bella; Gollasch, Stephan; Minchin, Dan; Narščius, Aleksas; Olenin, Sergej; Ojaveer, Henn
2018-02-01
The biological traits of the sixty-eight most widespread multicellular non-indigenous species (MWNIS) in European Seas: Baltic Sea, Western European Margin of the Atlantic Ocean and the Mediterranean Sea were examined. Data for nine biological traits was analyzed, and a total of 41 separate categories were used to describe the biological and ecological functions of these NIS. Our findings show that high dispersal ability, high reproductive rate and ecological generalization are the biological traits commonly associated with MWNIS. The functional groups that describe most of the 68 MWNIS are: photoautotrophic, zoobenthic (both sessile and motile) and nektonic predatory species. However, these 'most widespread' species comprise a wide range of taxa and biological trait profiles; thereby a clear "identikit of a perfect invader" for marine and brackish environments is difficult to define. Some traits, for example: "life form", "feeding method" and "mobility", feature multiple behaviours and strategies. Even species introduced by a single pathway, e.g. vessels, feature diverse biological trait profiles. MWNIS likely to impact community organization, structure and diversity are often associated with brackish environments. For many traits ("life form", "sociability", "reproductive type", "reproductive frequency", "haploid and diploid dispersal" and "mobility"), the categories mostly expressed by the impact-causing MWNIS do not differ substantially from the whole set of MWNIS.
The role of the expanded function nurse in fertility preservation.
Keating, C E
1992-01-01
The women's health care nurse practitioner has a unique opportunity to provide care to women in all stages of the reproductive life span. The care and guidance provided can affect general gynecologic health and the patient's ability to conceive. Crucial decisions about contraception and life-style choices have a far-reaching impact on reproductive potential. Women must be made aware of the issues surrounding these topics so they can make appropriate choices. The nurse practitioner, in the role of primary care provider, can assist women in this decision making process.
Neuroendocrine and behavioral implications of endocrine disrupting chemicals in quail
Ottinger, M.A.; Abdelnabi, M.A.; Henry, P.; McGary, S.; Thompson, N.; Wu, J.M.
2001-01-01
Studies in our laboratory have focused on endocrine, neuroendocrine, and behavioral components of reproduction in the Japanese quail. These studies considered various stages in the life cycle, including embryonic development, sexual maturation, adult reproductive function, and aging. A major focus of our research has been the role of neuroendocrine systems that appear to synchronize both endocrine and behavioral responses. These studies provide the basis for our more recent research on the impact of endocrine disrupting chemicals (EDCs) on reproductive function in the Japanese quail. These endocrine active chemicals include pesticides, herbicides, industrial products, and plant phytoestrogens. Many of these chemicals appear to mimic vertebrate steroids, often by interacting with steroid receptors. However, most EDCs have relatively weak biological activity compared to native steroid hormones. Therefore, it becomes important to understand the mode and mechanism of action of classes of these chemicals and sensitive stages in the life history of various species. Precocial birds, such as the Japanese quail, are likely to be sensitive to EDC effects during embryonic development, because sexual differentiation occurs during this period. Accordingly, adult quail may be less impacted by EDC exposure. Because there are a great many data available on normal development and reproductive function in this species, the Japanese quail provides an excellent model for examining the effects of EDCs. Thus, we have begun studies using a Japanese quail model system to study the effects of EDCs on reproductive endocrine and behavioral responses. In this review, we have two goals: first, to provide a summary of reproductive development and sexual differentiation in intact Japanese quail embryos, including ontogenetic patterns in steroid hormones in the embryonic and maturing quail. Second, we discuss some recent data from experiments in our laboratory in which EDCs have been tested in Japanese quail. The Japanese quail provides an excellent avian model for testing EDCs because this species has well-characterized reproductive endocrine and behavioral responses. Considerable research has been conducted in quail in which the effects of embryonic steroid exposure have been studied relative to reproductive behavior. Moreover, developmental processes have been studied extensively and include investigations of the reproductive axis, thyroid system, and stress and immune responses. We have conducted a number of studies, which have considered long-term neuroendocrine consequences as well as behavioral responses to steroids. Some of these studies have specifically tested the effects of embryonic steroid exposure on later reproductive function in a multigenerational context. A multigenerational exposure provides a basis for understanding potential exposure scenarios in the field. In addition, potential routes of exposure to EDCs for avian species are being considered, as well as differential effects due to stage of the life cycle at exposure to an EDC. The studies in our laboratory have used both diet and egg injection as modes of exposure for Japanese quail. In this way, birds were exposed to a specific dose of an EDC at a selected stage in development by injection. Alternatively, dietary exposure appears to be a primary route of exposure; therefore experimental exposure through the diet mimics potential field situations. Thus, experiments should consider a number of aspects of exposure when attempting to replicate field exposures to EDCs.
Progesterone Receptors: Form and Function in Brain
Brinton, Roberta Diaz; Thompson, Richard F.; Foy, Michael R.; Baudry, Michel; Wang, JunMing; Finch, Caleb E; Morgan, Todd E.; Stanczyk, Frank Z.; Pike, Christian J.; Nilsen, Jon
2008-01-01
Emerging data indicate that progesterone has multiple non-reproductive functions in the central nervous system to regulate cognition, mood, inflammation, mitochondrial function, neurogenesis and regeneration, myelination and recovery from traumatic brain injury. Progesterone-regulated neural responses are mediated by an array of progesterone receptors (PR) that include the classic nuclear PRA and PRB receptors and splice variants of each, the seven transmembrane domain 7TMPRβ and the membrane-associated 25-Dx PR (PGRMC1). These PRs induce classic regulation of gene expression while also transducing signaling cascades that originate at the cell membrane and ultimately activate transcription factors. Remarkably, PRs are broadly expressed throughout the brain and can be detected in every neural cell type. The distribution of PRs beyond hypothalamic borders, suggests a much broader role of progesterone in regulating neural function. Despite the large body of evidence regarding progesterone regulation of reproductive behaviors and estrogen-inducible responses as well as effects of progesterone metabolite neurosteroids, much remains to be discovered regarding the functional outcomes resulting from activation of the complex array of PRs in brain by gonadally and / or glial derived progesterone. Moreover, the impact of clinically used progestogens and developing selective PR modulators for targeted outcomes in brain is a critical avenue of investigation as the non-reproductive functions of PRs have far-reaching implications for hormone therapy to maintain neurological health and function throughout menopausal aging. PMID:18374402
Mutations and polymorphisms in FSH receptor: functional implications in human reproduction.
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.
Role of exercise training in polycystic ovary syndrome: a systematic review and meta-analysis.
Benham, J L; Yamamoto, J M; Friedenreich, C M; Rabi, D M; Sigal, R J
2018-06-12
Preliminary evidence suggests exercise in polycystic ovary syndrome (PCOS) may improve reproductive and cardiometabolic parameters. Our primary aim was to determine the impact of exercise training on reproductive health in women with PCOS. Our secondary aim was to determine the effect of exercise training on cardiometabolic indices. A systematic review of published literature was conducted using MEDLINE and EMBASE based on a pre-published protocol (PROSPERO CRD42017065324). The search was not limited by year. Randomized controlled trials, non-randomized controlled trials and uncontrolled trials that evaluated an exercise intervention in women with PCOS and reported reproductive outcomes were included. Reproductive outcomes were analysed semi-quantitatively and a meta-analysis was conducted for reported cardiometabolic outcomes. Of 517 screened abstracts, 14 studies involving 617 women with PCOS were included: seven randomized controlled trials, one non-randomized controlled trial and six uncontrolled trials. There were insufficient published data to describe the effect of exercise interventions on ovulation quantitatively, but semi-quantitative analysis suggested that exercise interventions may improve menstrual regularity, pregnancy and ovulation rates. Our meta-analysis found that exercise improved lipid profiles and decreased waist circumference, systolic blood pressure and fasting insulin. The impact of exercise interventions on reproductive function remains unclear. However, our meta-analysis suggests that exercise interventions may improve cardiometabolic profiles in women with PCOS. © 2018 World Obesity Federation.
Impact of hypocaloric dietary intervention on ovulation in obese women with PCOS.
Jarrett, Brittany Y; Lujan, Marla E
2016-10-31
Polycystic ovary syndrome (PCOS) is a common cause of ovulatory dysfunction impacting women of reproductive age. Obesity and insulin resistance are thought to potentiate disruptions in antral follicle development that result in chronic anovulation, and as such, have become important therapeutic targets of dietary interventions aimed at weight loss. Caloric restriction has been shown to promote sporadic ovulation in obese women with PCOS, but improvements have occurred across a wide range of patients and little has been garnered about the factors that distinguish responders from non-responders. Further, few studies have evaluated the likelihood for modest weight loss to restore normal ovulatory cyclicity in PCOS. Consensus regarding the impact of dietary intervention on ovulation has been limited by variability in the measures used to characterize and report ovulatory status across studies. In response, this review provides an assessment of the evidence surrounding the effectiveness of hypocaloric dietary intervention to normalize ovulatory function in PCOS. The impact of physiological versus methodological factors on the evaluation of ovulatory status is discussed and recommendations to strengthen future studies in this area are provided. Ultimately, further research is needed to understand the optimal dietary or lifestyle approaches that promote ovulation and sustained improvements in reproductive function in PCOS.
Impact of hypocaloric dietary intervention on ovulation in obese women with PCOS
Jarrett, Brittany Y.; Lujan, Marla E.
2016-01-01
Polycystic ovary syndrome (PCOS) is a common cause of ovulatory dysfunction impacting women of reproductive age. Obesity and insulin resistance are thought to potentiate disruptions in antral follicle development that result in chronic anovulation, and as such, have become important therapeutic targets of dietary interventions aimed at weight loss. Caloric restriction has been shown to promote sporadic ovulation in obese women with PCOS, but improvements have occurred across a wide range of patients and little has been garnered about the factors that distinguish responders from non-responders. Further, few studies have evaluated the likelihood for modest weight loss to restore normal ovulatory cyclicity in PCOS. Consensus regarding the impact of dietary intervention on ovulation has been limited by variability in the measures used to characterize and report ovulatory status across studies. In response, this review provides an assessment of the evidence surrounding the effectiveness of hypocaloric dietary intervention to normalize ovulatory function in PCOS. The impact of physiological versus methodological factors on the evaluation of ovulatory status is discussed and recommendations to strengthen future studies in this area are provided. Ultimately, further research is needed to understand the optimal dietary or lifestyle approaches that promote ovulation and sustained improvements in reproductive function in PCOS. PMID:27799625
While it is known that adrenal steroids impact reproduction and a variety of other physiological and behavioral functions, disruption of the HPA-axis is not typically considered in toxicological studies. Here we characterize changes in basal corticosterone (CORT) and progesterone...
USDA-ARS?s Scientific Manuscript database
The impact of adult weight, age, and density on reproduction of Tenebrio molitor L. (Coleoptera: Tenebrionidae) was studied. The impact of adult weight on reproduction was determined in two ways: 1) counting the daily progeny of individual adult pairs of known weight and analyzing the data with line...
El-Hefnawy, Talal; Hernandez, Claudia; Stabile, Laura P
2017-09-01
Endocrine disrupting chemicals (EDCs) are ubiquitous compounds known for negative impacts on reproductive functions and for increasing cancer risk. EDCs are believed to cause the harmful effects in part through their inappropriate low-affinity binding to steroid receptors and other possible non-receptor mediated paradigms, however there is a need to further elucidate other mechanisms involving the direct and indirect impact of EDCs on reproductive functions. We examined the metabolism of 17β-estradiol (E2) and estrone (E1) by cell-free hepatic cytosol in the presence of alkylphenols (nonylphenol/NP and 4-tert-octylphenol/tOP), Dichlorodiphenyltrichloroethane (4,4'-DDT) and other EDCs. Tandem liquid chromatography mass spectrometry was utilized to quantitatively assess the impact of each EDC on estrogen clearance, inter-conversions and downstream metabolism by mouse liver cytosol. The results revealed that NP and tOP (0.1-3μg/mL) significantly reduced the hepatic cytosol clearance and biotransformation of estrogens with inclination for accumulating E2, the stronger estrogen form, than E1. Alkylphenols also caused up to a 34-fold increase in the E2/E1 ratio possibly by suppressing the hepatic E2→E1 conversion by 17β-hydroxysteroid dehydrogenase (17βHSD) types 2, 4 while displaying a weaker inhibition of E1→E2 conversion by type 1, 17βHSD. On the other hand, the pesticide 4,4'-DDT was a weaker inhibitor of clearance of estrogens by the cytosol preparations when compared to alkylphenols, whereas chemicals such as phthalates and atrazine were ineffective. Our data suggest that exposure to NP, tOP and DDT can indirectly increase the estrogenic load by suppressing the hepatic clearance of estrogens and by elevating the E2/1 ratio and could therefore increase the risk of reproductive lesions. Copyright © 2017 Society for Biology of Reproduction & the Institute of Animal Reproduction and Food Research of Polish Academy of Sciences in Olsztyn. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.
Similar causes of various reproductive disorders in early life.
Svechnikov, Konstantin; Stukenborg, Jan-Bernd; Savchuck, Iuliia; Söder, Olle
2014-01-01
During the past few decades, scientific evidence has been accumulated concerning the possible adverse effects of the exposure to environmental chemicals on the well-being of wildlife and human populations. One large and growing group of such compounds of anthropogenic or natural origin is referred to as endocrine-disrupting chemicals (EDCs), due to their deleterious action on the endocrine system. This concern was first focused on the control of reproductive function particularly in males, but has later been expanded to include all possible endocrine functions. The present review describes the underlying physiology behind the cascade of developmental events that occur during sexual differentiation of males and the specific role of androgen in the masculinization process and proper organogenesis of the external male genitalia. The impact of the genetic background, environmental exposures and lifestyle factors in the etiology of hypospadias, cryptorchidism and testicular cancer are reviewed and the possible role of EDCs in the development of these reproductive disorders is discussed critically. Finally, the possible direct and programming effects of exposures in utero to widely use therapeutic compounds, environmental estrogens and other chemicals on the incidence of reproductive abnormalities and poor semen quality in humans are also highlighted.
Non-invasive reproductive and stress endocrinology in amphibian conservation physiology
Narayan, E. J.
2013-01-01
Non-invasive endocrinology utilizes non-invasive biological samples (such as faeces, urine, hair, aquatic media, and saliva) for the quantification of hormones in wildlife. Urinary-based enzyme immunoassay (EIA) and radio-immunoassay have enabled the rapid quantification of reproductive and stress hormones in amphibians (Anura: Amphibia). With minimal disturbance, these methods can be used to assess the ovarian and testicular endocrine functions as well as physiological stress in captive and free-living populations. Non-invasive endocrine monitoring has therefore greatly advanced our knowledge of the functioning of the stress endocrine system (the hypothalamo–pituitary–interrenal axis) and the reproductive endocrine system (the hypothalamo–pituitary–gonadal axis) in the amphibian physiological stress response, reproductive ecology, health and welfare, and survival. Biological (physiological) validation is necessary for obtaining the excretory lag time of hormone metabolites. Urinary-based EIA for the major reproductive hormones, estradiol and progesterone in females and testosterone in males, can be used to track the reproductive hormone profiles in relationship to reproductive behaviour and environmental data in free-living anurans. Urinary-based corticosterone metabolite EIA can be used to assess the sublethal impacts of biological stressors (such as invasive species and pathogenic diseases) as well as anthropogenic induced environmental stressors (e.g. extreme temperatures) on free-living populations. Non-invasive endocrine methods can also assist in the diagnosis of success or failure of captive breeding programmes by measuring the longitudinal patterns of changes in reproductive hormones and corticosterone within captive anurans and comparing the endocrine profiles with health records and reproductive behaviour. This review paper focuses on the reproductive and the stress endocrinology of anurans and demonstrates the uses of non-invasive endocrinology for advancing amphibian conservation physiology. It also provides key technical considerations for future research that will increase the accuracy and reliability of the data and the value of non-invasive endocrinology within the conceptual framework of conservation physiology. PMID:27293595
Jewell, Elizabeth L; Aghajanian, Carol; Montovano, Margaret; Lewin, Sharyn N; Baser, Raymond E; Carter, Jeanne
2018-03-01
To assess the emotional, reproductive, sexual health, and relationship concerns of women treated for gestational trophoblastic neoplasia (GTN) and examine associations with ß-hCG surveillance. This institutional review board approved study surveyed GTN survivors (n = 51) who received treatment from 1996 to 2008. Fifty-one women, including those actively followed or formerly treated, were surveyed. The survey consisted of background/medical information, the Reproductive Concerns Scale, the Female Sexual Function Index, an item from the Abbreviated Dyadic Adjustment Scale, the Center for Epidemiologic Studies-Depression scale, the Menopausal Symptom Checklist, the Impact of Life Events Scale, and exploratory items. Mean age at diagnosis was 37.1 years; 41.6 years at study enrollment. Twenty-seven patients (56%) expressed worry about treatment harm and 30 (60%) about recurrence. Twenty percent reported significant depressive symptomatology. Mild cancer-related distress, reproductive concerns, sexual dysfunction, and bothersome menopausal symptoms were noted. Nineteen patients (40%) rated their ß-hCG surveillance worry as "high." Among patients who attempted conception after treatment, 3 of 12 (25%) succeeded in the ß-hCG high-worry group versus 13 of 19 (68%) in the ß-hCG low-worry group. Survivors with high ß-hCG worry had greater reproductive concerns than those with low worry (p = 0.002) and reported less sexual desire (p = 0.025). There was no difference in the number of low-worry versus high-worry participants in active surveillance (p = 0.09). Our study suggests that cancer-specific distress, sexual health, and reproductive concerns continue to impact women years after treatment. High worry about ß-hCG surveillance is negatively associated with the emotional well-being of GTN survivors and possibly influences reproductive attempts and success.
Inhibition of enzymes involved in the synthesis of sex steroids can substantially impact developmental and reproductive processes controlled by the hypothalmic-pituitary-gonadal (HPG) axis. A key steroidogenic enzyme that has received little attention from a toxicological perspe...
This project was based upon outcomes from earlier work conducted under APM 465 to test the hypothesis that the chlorotriazine herbicide, atrazine (ATR), causes an increase in serum estrogens through an induction of aromatase (CYP19) gene expression. The current research has invol...
Impacts of Sublethal Mercury Exposure on Birds: A Detailed Review.
Whitney, Margaret C; Cristol, Daniel A
Mercury is a ubiquitous environmental contaminant known to accumulate in, and negatively affect, fish-eating and oceanic bird species, and recently demonstrated to impact some terrestrial songbirds to a comparable extent. It can bioaccumulate to concentrations of >1 μg/g in tissues of prey organisms such as fish and insects. At high enough concentrations, exposure to mercury is lethal to birds. However, environmental exposures are usually far below the lethal concentrations established by dosing studies.The objective of this review is to better understand the effects of sublethal exposure to mercury in birds. We restricted our survey of the literature to studies with at least some exposures >5 μg/g. The majority of sublethal effects were subtle and some studies of similar endpoints reached different conclusions. Strong support exists in the literature for the conclusion that mercury exposure reduces reproductive output, compromises immune function, and causes avoidance of high-energy behaviors. For some endpoints, notably certain measures of reproductive success, endocrine and neurological function, and body condition, there is weak or contradictory evidence of adverse effects and further study is required. There was no evidence that environmentally relevant mercury exposure affects longevity, but several of the sublethal effects identified likely do result in fitness reductions that could adversely impact populations. Overall, 72% of field studies and 91% of laboratory studies found evidence of deleterious effects of mercury on some endpoint, and thus we can conclude that mercury is harmful to birds, and the many effects on reproduction indicate that bird population declines may already be resulting from environmental mercury pollution.
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 immune system to respond to subsequent changes in day length.
Reproduction Symposium: developmental programming of reproductive and metabolic health.
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 concept for the developmental origin of fertility and metabolic disorders. Studies with the environmental endocrine disruptor bisphenol A (BPA) show that reproductive disruptions found in prenatal BPA-treated sheep are similar to those seen in prenatal T-treated sheep. The ubiquitous exposure to endocrine disrupting compounds with steroidogenic potential via the environment and food sources calls for studies addressing the impact of developmental exposure to environmental steroid mimics on reproductive function.
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.
Ida, Takashi Y.; Harder, Lawrence D.; Kudo, Gaku
2012-01-01
Background The production of flowers, fruits and seeds demands considerable energy and nutrients, which can limit the allocation of these resources to other plant functions and, thereby, influence survival and future reproduction. The magnitude of the physiological costs of reproduction depends on both the factors limiting seed production (pollen, ovules or resources) and the capacity of plants to compensate for high resource demand. Methods To assess the magnitude and consequences of reproductive costs, we used shading and defoliation to reduce photosynthate production by fully pollinated plants of a perennial legume, Oxytropis sericea (Fabaceae), and examined the resulting impact on photosynthate allocation, and nectar, fruit and seed production. Key Results Although these leaf manipulations reduced photosynthesis and nectar production, they did not alter photosynthate allocation, as revealed by 13C tracing, or fruit or seed production. That photosynthate allocation to reproductive organs increased >190 % and taproot mass declined by 29 % between flowering and fruiting indicates that reproduction was physiologically costly. Conclusions The insensitivity of fruit and seed production to leaf manipulation is consistent with either compensatory mobilization of stored resources or ovule limitation. Seed production differed considerably between the two years of the study in association with contrasting precipitation prior to flowering, perhaps reflecting contrasting limits on reproductive performance. PMID:22021817
Kilcoyne, Karen R; Mitchell, Rod T
2017-12-01
Human male reproductive disorders (cryptorchidism, hypospadias, testicular cancer and low sperm counts) are common and some may be increasing in incidence worldwide. These associated disorders can arise from subnormal testosterone production during fetal life. This has resulted in a focus on in-utero environmental influences that may result in reproductive effects on the offspring in later life. Over recent years, there has been a dramatic increase in the scientific literature describing associations between in-utero environmental exposures (eg, industrial chemicals and pharmaceuticals) and subsequent reproductive outcomes in male offspring. This includes studies investigating a potential role for in-utero analgesic exposure(s) on the fetal testis; however, providing definitive evidence of such effects presents numerous challenges. In this review, we describe an approach to assessing the potential clinical relevance of in-utero (and postnatal) environmental exposures on subsequent male reproductive function using exposure to the analgesic paracetamol as an example. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
Cavallin, Jenna E.; Jensen, Kathleen M.; Kahl, Michael D.; Villeneuve, Daniel L.; Lee, Kathy E.; Schroeder, Anthony L.; Mayasich, Joe; Eid, Evan P.; Nelson, Krysta R.; Milsk, Rebecca Y.; Blackwell, Brett R.; Berninger, Jason P.; LaLone, Carlie A.; Blanskma, Chad; Jicha, Terri M.; Elonen, Colleen M.; Johnson, Rodney C.; Ankley, Gerald T.
2016-01-01
Wastewater treatment plant (WWTP) effluents are known contributors of chemical mixtures into the environment. Of particular concern are endocrine-disrupting compounds, such as estrogens, which can affect the hypothalamic-pituitary-gonadal axis function in exposed organisms. The present study examined reproductive effects in fathead minnows exposed for 21 d to a historically estrogenic WWTP effluent. Fathead minnow breeding pairs were held in control water or 1 of 3 effluent concentrations (5%, 20%, and 100%) in a novel onsite, flow-through system providing real-time exposure. The authors examined molecular and biochemical endpoints representing key events along adverse outcome pathways linking estrogen receptor activation and other molecular initiating events to reproductive impairment. In addition, the authors used chemical analysis of the effluent to construct a chemical-gene interaction network to aid in targeted gene expression analyses and identifying potentially impacted biological pathways. Cumulative fecundity was significantly reduced in fish exposed to 100% effluent but increased in those exposed to 20% effluent, the approximate dilution factor in the receiving waters. Plasma vitellogenin concentrations in males increased in a dose-dependent manner with effluent concentration; however, male fertility was not impacted. Although in vitro analyses, analytical chemistry, and biomarker responses confirmed the effluent was estrogenic, estrogen receptor agonists were unlikely the primary driver of impaired reproduction. The results provide insights into the significance of pathway-based effects with regard to predicting adverse reproductive outcomes.
Impact of the environment on reproductive health.
1991-01-01
The WHO workshop on the impact of the environment on reproductive health is summarized. Topics include the nature of environmental factors affecting reproductive health, environmental factors blamed for declining sperm quantity and quality, the effects of natural and man-made disasters on reproductive health, chemical pollutants, how the environment damages reproductive health, and research needs for better research methodologies and surveillance data. Recommendations are made to: 1) promote international research collaboration with an emphasis on consistency of methodological approaches for assessing developmental and reproductive toxicity, on development of improved surveillance systems and data bases, an strengthening international disaster alert and evaluation systems; 2) promote research capabilities for multidisciplinary studies, for interactive studies of the environment and cellular processes, and for expansion of training and education; and 3) take action on priority problems of exposure to chemical, physical, and biological agents, of exposure to pesticides among specific populations, and of inadequate screening methods for identification of environmental chemicals. The costs of environmental injury to reproduction include subfertility, intrauterine growth retardation, spontaneous abortion, and various birth defects. Developed country's primary threats are from chemical pollution, radiation, and stress. There is a large gap in knowledge. Caution is urged in understanding the direct relationship between environmental causes and infertility. Sexual health is difficult to assess and research is suggested. Exposure to excessive vitamin A and toxic chemicals are cited as agents probably having serious effects on malformations. Sperm quality has declined over the decades; there is speculation about the potential causes. The effects of radiation such as at Chernobyl are described. Toxic chemical exposure such as in Bhopal, India killed thousands. Neurological 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.
Sex Hormones and Healthy Psychological Aging in Women
Navarro-Pardo, Esperanza; Holland, Carol A.; Cano, Antonio
2018-01-01
Besides their key role in reproduction, estrogens have effects in several organs in the body, as confirmed by the identification of estrogen receptors (ER) in multiple tissues. Experimental evidence has shown that estrogens have significant impacts on the central nervous system (CNS), and a key question is to what extent the fall in estrogen levels in the blood that occurs with increasing age, particularly around and following the menopause, has an impact on the cognitive function and psychological health of women, specifically regarding mood. This review will consider direct effects of menopausal changes in estrogens on the brain, including cognitive function and mood. Secondary pathways whereby health factors affected by changes in estrogens may interact with CNS functions, such as cardiovascular factors, will be reviewed as well insofar as they also have an impact on cognitive function. Finally, because decline in estrogens may induce changes in the CNS, there is interest in clarifying whether hormone therapy may offer a beneficial balance and the impact of hormone therapy on cognition will also be considered. PMID:29375366
Developmental programming of reproductive and metabolic health1,2
Padmanabhan, V.; Veiga-Lopez, A.
2014-01-01
The 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 (~5 mo gestation and ~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 non-invasive 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 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 three 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/metabolic diseases, insulin resistance, hypertension and behavioral deficits. Collectively, the reproductive and metabolic deficits of prenatal T-treated sheep provide proof of concept for the developmental origin of fertility and metabolic disorders. Studies with the environmental endocrine disruptor, bisphenol-A (BPA), show that reproductive disruptions found in prenatal BPA-treated sheep are similar to those seen in prenatal T-treated sheep. The ubiquitous exposure to endocrine disrupting compounds (EDC) with steroidogenic potential via the environment and food sources, calls for studies addressing the impact of developmental exposure to environmental steroid mimics on reproductive function. PMID:25074449
Effect of environmental contaminants on mammalian testis.
Manfo, Faustin P T; Nantia, Edouard A; Mathur, Premendu P
2014-01-01
Exposure of humans and wildlife to pollutants released in the environment is a centre of attention nowadays. Many of these chemicals (generally referred to as environmental pollutants) have been shown to interfere with normal hormonal signalling and biological functions, leading to reproductive disorders or infertility, which has been a matter of concern within the recent decades. The present paper reviews adverse effects of these toxicants on mammalian testes, with emphasis on alteration of steroidogenesis, spermatogenesis, and histopathological effects. From the publications reviewed, it appears that environmental toxicants, especially heavy metals and organic chemicals of synthetic and microbiological origins, disrupt hormone production and action in the mammalian testes. Endocrine disruption leads to disorders of testicular function and thereby compromises the normal phenotypic development of male sexual characteristics, initiation and maintenance of spermatogenesis. The toxicants also induce impairment of testicular cells function, testicular histology, and sperm cells function directly. The release of the toxicants in the environment is still ongoing, despite alarming quantities that already exist in the atmosphere. If appropriate measures are not taken, their impact on the male reproductive function and especially on testicular function will be more serious.
The impacts of adverse environments during the prenatal and/or early postnatal periods may be manifested as functional deficits that occur later in life. Epidemiological studies have shown an association of sub-optimal pregnancy outcomes in one generation with similar events in t...
Dominoni, Davide M; Quetting, Michael; Partecke, Jesko
2013-01-01
Light pollution is known to affect important biological functions of wild animals, including daily and annual cycles. However, knowledge about long-term effects of chronic exposure to artificial light at night is still very limited. Here we present data on reproductive physiology, molt and locomotor activity during two-year cycles of European blackbirds (Turdus merula) exposed to either dark nights or 0.3 lux at night. As expected, control birds kept under dark nights exhibited two regular testicular and testosterone cycles during the two-year experiment. Control urban birds developed testes faster than their control rural conspecifics. Conversely, while in the first year blackbirds exposed to light at night showed a normal but earlier gonadal cycle compared to control birds, during the second year the reproductive system did not develop at all: both testicular size and testosterone concentration were at baseline levels in all birds. In addition, molt sequence in light-treated birds was more irregular than in control birds in both years. Analysis of locomotor activity showed that birds were still synchronized to the underlying light-dark cycle. We suggest that the lack of reproductive activity and irregular molt progression were possibly the results of i) birds being stuck in a photorefractory state and/or ii) chronic stress. Our data show that chronic low intensities of light at night can dramatically affect the reproductive system. Future studies are needed in order to investigate if and how urban animals avoid such negative impact and to elucidate the physiological mechanisms behind these profound long-term effects of artificial light at night. Finally we call for collaboration between scientists and policy makers to limit the impact of light pollution on animals and ecosystems.
Galic, Nika; Sullivan, Lauren L; Grimm, Volker; Forbes, Valery E
2018-04-01
Ecosystems are exposed to multiple stressors which can compromise functioning and service delivery. These stressors often co-occur and interact in different ways which are not yet fully understood. Here, we applied a population model representing a freshwater amphipod feeding on leaf litter in forested streams. We simulated impacts of hypothetical stressors, individually and in pairwise combinations that target the individuals' feeding, maintenance, growth and reproduction. Impacts were quantified by examining responses at three levels of biological organisation: individual-level body sizes and cumulative reproduction, population-level abundance and biomass and ecosystem-level leaf litter decomposition. Interactive effects of multiple stressors at the individual level were mostly antagonistic, that is, less negative than expected. Most population- and ecosystem-level responses to multiple stressors were stronger than expected from an additive model, that is, synergistic. Our results suggest that across levels of biological organisation responses to multiple stressors are rarely only additive. We suggest methods for efficiently quantifying impacts of multiple stressors at different levels of biological organisation. © 2018 John Wiley & Sons Ltd/CNRS.
Marijuana, phytocannabinoids, the endocannabinoid system, and male fertility.
du Plessis, Stefan S; Agarwal, Ashok; Syriac, Arun
2015-11-01
Marijuana has the highest consumption rate among all of the illicit drugs used in the USA, and its popularity as both a recreational and medicinal drug is increasing especially among men of reproductive age. Male factor infertility is on the increase, and the exposure to the cannabinoid compounds released by marijuana could be a contributing cause. The endocannabinoid system (ECS) is deeply involved in the complex regulation of male reproduction through the endogenous release of endocannabinoids and binding to cannabinoid receptors. Disturbing the delicate balance of the ECS due to marijuana use can negatively impact reproductive potential. Various in vivo and in vitro studies have reported on the empirical role that marijuana plays in disrupting the hypothalamus-pituitary-gonadal axis, spermatogenesis, and sperm function such as motility, capacitation, and the acrosome reaction. In this review, we highlight the latest evidence regarding the effect of marijuana use on male fertility and also provide a detailed insight into the ECS and its significance in the male reproductive system.
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.
Witorsch, Raphael J
2016-01-01
This article reviews the influence of the hypothalamo-pituitary-adrenocortical (HPA) axis on mammalian male and female reproduction and development of offspring and its potential impact on the identification of endocrine disruptive chemicals by in vivo assays. In the adult male rat and baboon, stress suppresses testosterone secretion via a direct inhibitory effect of elevated glucocorticoids on Leydig cells. In adult female sheep, stress disrupts reproductive function via multi-stage mechanisms involving glucocorticoid-mediated suppression of LH secretion, LH action on the ovary and the action of estradiol on its target cells (e.g., uterus). While physiological concentrations of endogenous glucocorticoids are supportive of fetal development, excessive glucocorticoids in utero (i.e., maternal stress) adversely affect mammalian offspring by "programing" abnormalities that are primarily manifest postpartum. The influence of stress on reproduction and development can also be mediated by 11β-hydroxysteroid dehydrogenase (HSD), a bi-directional oxidative:reductive pathway, which governs the balance between biologically active (reduced) endogenous glucocorticoid and inactive (oxidized) metabolites. This pathway is mediated primarily by two isozymes, 11β - HSD1 (reductase) and 11β-HSD2 (oxidase) which act both in an intracrine (intracellular) and endocrine (systemic) fashion. The 11β-HSD pathway appears to play a variety of physiological roles in mammalian reproduction and development and is a target for selected xenobiotics. The effects of the HPA axis on mammalian reproduction and development are potential confounders for in vivo bioassays in rodents employed to identify endocrine disruptive chemicals. Accordingly, consideration of the impact of the HPA axis should be incorporated into the design of bioassays for evaluating endocrine disruptors.
Dioxin pollution disrupts reproduction in male Japanese field mice.
Ishiniwa, Hiroko; Sakai, Mizuki; Tohma, Shimon; Matsuki, Hidenori; Takahashi, Yukio; Kajiwara, Hideo; Sekijima, Tsuneo
2013-11-01
Dioxins cause various adverse effects in animals including teratogenesis, induction of drug metabolizing enzymes, tumor promotion, and endocrine disruption. Above all, endocrine disruption is known to disturb reproduction in adult animals and may, also seriously impact their offspring. However, most previous studies have quantified the species-specific accumulation of dioxins, whereas few studies have addressed the physiological impacts of dioxins on wildlife, such as reduced reproductive function. Here we clarify an effect of endocrine disruption caused by dioxins on the Japanese field mouse, Apodemus speciosus. Japanese field mice collected from various sites polluted with dioxins accumulated high concentrations of dioxins in their livers. Some dioxin congeners, especially, 1,2,3,4,6,7,8-heptachlorodibenzo-p-dioxin, 3,3',4,4',5-pentachloro biphenyl, 1,2,3,4,6,7,8-heptachlorodibenzofuran, and octachlorodibenzo-p-dioxin, which showed high biota-soil accumulation factors, contributed to concentration of dioxins in mouse livers with an increase of accumulation of total dioxins. As for physiological effects on the Japanese field mouse, high levels of cytochrome P450 1A1 (CYP1A1) mRNA, a drug metabolizing enzyme induced by dioxins, were found in the livers of mice captured at polluted sites. Furthermore, at such sites polluted with dioxins, increased CYP1A1 expression coincided with reduced numbers of active spermatozoa in mice. Thus, disruption in gametogenesis observed in these mice suggests that dioxins not only negatively impact reproduction among Japanese field mice, but might also act as a kind of selection pressure in a chemically polluted environment.
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.
Sex differences in episodic memory in early midlife: impact of reproductive aging.
Rentz, Dorene M; Weiss, Blair K; Jacobs, Emily G; Cherkerzian, Sara; Klibanski, Anne; Remington, Anne; Aizley, Harlyn; Goldstein, Jill M
2017-04-01
Few have characterized cognitive changes with age as a function of menopausal stage relative to men, or sex differences in components of memory in early midlife. The study aim was to investigate variation in memory function in early midlife as a function of sex, sex steroid hormones, and reproductive status. A total of 212 men and women aged 45 to 55 were selected for this cross-sectional study from a prenatal cohort of pregnancies whose mothers were originally recruited in 1959 to 1966. They underwent clinical and cognitive testing and hormonal assessments of menopause status. Multivariate general linear models for multiple memory outcomes were used to test hypotheses controlling for potential confounders. Episodic memory, executive function, semantic processing, and estimated verbal intelligence were assessed. Associative memory and episodic verbal memory were assessed using Face-Name Associative Memory Exam (FNAME) and Selective Reminding Test (SRT), given increased sensitivity to detecting early cognitive decline. Impacts of sex and reproductive stage on performance were tested. Women outperformed men on all memory measures including FNAME (β = -0.30, P < 0.0001) and SRT (β = -0.29, P < 0.0001). Furthermore, premenopausal and perimenopausal women outperformed postmenopausal women on FNAME (initial learning, β= 0.32, P = 0.01) and SRT (recall, β= 2.39, P = 0.02). Across all women, higher estradiol was associated with better SRT performance (recall, β = 1.96, P = 0.01) and marginally associated with FNAME (initial learning, β = 0.19, P = 0.06). This study demonstrated that, in early midlife, women outperformed age-matched men across all memory measures, but sex differences were attenuated for postmenopausal women. Initial learning and memory retrieval were particularly vulnerable, whereas memory consolidation and storage were preserved. Findings underscore the significance of the decline in ovarian estradiol production in midlife and its role in shaping memory function.
NASA Astrophysics Data System (ADS)
Thomas, P.; Rahman, S.
2016-02-01
Knowledge of the effects of environmental exposure to hypoxia (dissolved oxygen: <2 mg/L) on critical physiological functions such as reproduction, growth and metabolism in both fish and invertebrates is essential for accurate predictions of its chronic impacts on marine communities. Marked disruption of reproduction and its endocrine control was observed in Atlantic croaker collected from the hypoxic region in the northern Gulf of Mexico. Recent research has shown that growth and its physiological upregulation is also impaired in hypoxia-exposed marine fish. Expression of insulin-like growth factor (IGF) binding protein (IGFBP), which inhibits growth, was increased in croaker livers, whereas plasma levels of IGF, the primary regulator of growth, were decreased in snapper after hypoxia exposure. In addition, hypoxia inducible factor-1 (HIF-1), which regulates changes in metabolism during adaptation to hypoxia, was upregulated in croaker collected from hypoxic environments. Interestingly, similar changes in the expression of IGFBP and HIF-1 have been found in marine crustaceans after hypoxia exposure, suggesting these responses to hypoxia are common to marine fish and invertebrates. Preliminary field studies indicate that hypoxia exposure also causes epigenetic modifications, including increases in global DNA methylation, and that these epigenetic changes can influence reproduction and growth in croaker. Epigenetic modifications can be passed to offspring and persist in future generations no longer exposed to an environmental stressor further aggravating its long-term adverse impacts on population abundance and delaying recovery. The growing availability of complete invertebrate genomes and high-throughput DNA sequencing indicates similar epigenetic studies can now be conducted with marine invertebrates. Collectively, the results indicate that environmental hypoxia exposure disrupts major physiological functions in fish and invertebrates critical for maintenance of their populations.
Advances in human reproductive ecology.
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 on lower ovarian function throughout adult life. There is a range of ovarian function along a continuum due to energetic stress. Evidence from the Lese in Zaire, the Tamang of Nepal, and Polish farm women outside Crakow suggest that workload affects ovarian function. Luteal function and ovulatory frequency is lower when women are losing weight. Among the Tamang losing weight between seasons there was evidence of lower ovarian function during the monsoon season. Polish farm women who work very hard in summer had lower ovarian function. The effect of lactation on amenorrhea appears to be due to the energetic stress on the mother in the intensity and duration of suckling. Women in poorer nutritional status may require more intense suckling. Seasonality of energy balance may be related to seasonality of female fecundity and conceptions.
Mirando, Mark A; Hamernik, Debora L
2006-03-01
The National Research Initiative (NRI) Competitive Grants Program is the U.S. Department of Agriculture's major competitive grants program and is administered by the Cooperative State Research, Education, and Extension Service (CSREES). Since its inception in 1991, the NRI has funded competitive grants in the discipline of animal reproduction. Previously, this program provided funding for a broad range of projects encompassing almost every subdiscipline in reproductive biology of farm animals, including aquatic species important to the aquaculture industry. During fiscal year 2004, the NRI Animal Reproduction Program narrowed the focus of funding priorities to the topics of infertility, basic mechanisms regulating fertility, cryopreservation of gametes, reducing the postpartum interval to conception, and sterilization methods or development of monosex populations. In response to a directive to further narrow the focus of funding priorities for fiscal year 2005 and beyond, CSREES conducted a Stakeholder Workshop on Funding Priorities in Animal Reproduction at the 37th Annual Meeting of the Society for the Study of Reproduction in Vancouver, Canada. More than 75 stakeholder scientists from a cross section of federal, public, and private institutions from across the United States participated in the workshop and provided recommendations to CSREES for future NRI-funding priorities in Animal Reproduction. The recommendations provided by stakeholders included continuing efforts to focus funding priorities into fewer high-impact areas relevant to animal agriculture and aquaculture. Recommendations also included movement back toward subdisciplines of animal reproduction that cut across all applicable species. The three funding priorities that consistently emerged as recommendations from the workshop participants were 1) gonadal function and production of gametes, 2) pituitary-hypothalamic function, and 3) embryo and conceptus development, including interaction between the conceptus and uterus. These funding priorities were considered when preparing the fiscal year 2006 NRI Request for Applications.
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.
Prostasomes--their effects on human male reproduction and fertility.
Burden, H P; Holmes, C H; Persad, R; Whittington, K
2006-01-01
The prostate is a glandular male accessory sex organ vital for normal fertility. It provides the prostatic component of seminal plasma which nourishes and protects sperm following ejaculation. Prostasomes are small (40-500 nm) membrane-bound vesicles produced by epithelial cells lining the prostate acini and are a component of prostatic secretions. Although the existence of these particles has been known for many years, their full function and relevance to reproductive health are largely unknown. Proteomic studies have shown a wide range of proteins (enzymes, structural proteins and novel, unannotated proteins) present in or on the surface of prostasomes providing them with a diverse nature. Interestingly prostasomes are able to fuse with sperm, this event and the associated transfer of proteins lies at the heart of many of their proposed functions. Sperm motility is increased by the presence of prostasomes and their fusion prevents premature acrosome reactions. Prostasomes have been shown to aid protection of sperm within the female reproductive tract because of immunosuppressive, antioxidant and antibacterial properties. Clinically these functions imply a role for prostasomes in male factor infertility. However, the very functions that promote fertility may have negative connotations in later life; recent work has suggested that prostasomes are involved in prostate cancer. Clearly more work is needed to clarify the role of these novel particles and their impact on men's health.
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.
Butler, Merlin G; Rafi, Syed K; McGuire, Austen; Manzardo, Ann M
2016-01-01
To provide an update of currently recognized clinically relevant candidate and known genes for human reproduction and related infertility plotted on high resolution chromosome ideograms (850 band level) and represented alphabetically in tabular form. Descriptive authoritative computer-based website and peer-reviewed medical literature searches used pertinent keywords representing human reproduction and related infertility along with genetics and gene mutations. A master list of genes associated with human reproduction and related infertility was generated with a visual representation of gene locations on high resolution chromosome ideograms. GeneAnalytics pathway analysis was carried out on the resulting list of genes to assess underlying genetic architecture for infertility. Advances in genetic technology have led to the discovery of genes responsible for reproduction and related infertility. Genes identified (N=371) in our search primarily impact ovarian steroidogenesis through sex hormone biology, germ cell production, genito-urinary or gonadal development and function, and related peptide production, receptors and regulatory factors. The location of gene symbols plotted on high resolution chromosome ideograms forms a conceptualized image of the distribution of human reproduction genes. The updated master list can be used to promote better awareness of genetics of reproduction and related infertility and advance discoveries on genetic causes and disease mechanisms. Copyright © 2015 Elsevier B.V. All rights reserved.
Neonatal agonism of ERβ impairs male reproductive behavior and attractiveness
Sullivan, Alana W.; Hamilton, Peter; Patisaul, Heather B.
2011-01-01
The organization of the developing male rodent brain is profoundly influenced by endogenous steroids, most notably estrogen. This process may be disrupted by estrogenic endocrine disrupting compounds (EDCs) resulting in altered sex behavior and the capacity to attract a mate in adulthood. To better understand the relative role each estrogen receptor (ER) subtype (ERα and ERβ) plays in mediating these effects, we exposed male Long Evans rats to estradiol benzoate (EB, 10 μg), vehicle, or agonists specific for ERβ (DPN, 1 mg/kg) or ERα (PPT, 1 mg/kg) daily for the first four days of life, and then assessed adult male reproductive behavior and attractiveness via a partner preference paradigm. DPN had a greater adverse impact than PPT on reproductive behavior, suggesting a functional role for ERβ in the organization of these male-specific behaviors. Therefore the impact of neonatal ERβ agonism was further investigated by repeating the experiment using vehicle, EB and additional DPN doses (0.5 mg/kg, 1 mg/kg, and 2 mg/kg bw). Exposure to DPN suppressed male reproductive behavior and attractiveness in a dose dependent manner. Finally, males were exposed to EB or an environmentally relevant dose of genistein (GEN, 10 mg/kg), a naturally occurring xenoestrogen, which has a higher relative binding affinity for ERβ than ERα. Sexual performance was impaired by GEN but not attractiveness. In addition to suppressing reproductive behavior and attractiveness, EB exposure significantly lowered the testis to body weight ratio, and circulating testosterone levels. DPN and GEN exposure only impaired behavior, suggesting that disrupted androgen secretion does not underlie the impairment. PMID:21554883
NASA Astrophysics Data System (ADS)
Burton, Jason C.; Wang, Shang; Behringer, Richard R.; Larina, Irina V.
2016-03-01
Infertility is a known major health concern and is estimated to impact ~15% of couples in the U.S. The majority of failed pregnancies occur before or during implantation of the fertilized embryo into the uterus. Understanding the mechanisms regulating development by studying mouse reproductive organs could significantly contribute to an improved understanding of normal development of reproductive organs and developmental causes of infertility in humans. Towards this goal, we report a three-dimensional (3D) imaging study of the developing mouse reproductive organs (ovary, oviduct, and uterus) using optical coherence tomography (OCT). In our study, OCT was used for 3D imaging of reproductive organs without exogenous contrast agents and provides micro-scale spatial resolution. Experiments were conducted in vitro on mouse reproductive organs ranging from the embryonic day 14.5 to adult stages. Structural features of the ovary, oviduct, and uterus are presented. Additionally, a comparison with traditional histological analysis is illustrated. These results provide a basis for a wide range of infertility studies in mouse models. Through integration with traditional genetic and molecular biology approaches, this imaging method can improve understanding of ovary, oviduct, and uterus development and function, serving to further contribute to our understanding of fertility and infertility.
Savage, Jessica A; Clearwater, Michael J; Haines, Dustin F; Klein, Tamir; Mencuccini, Maurizio; Sevanto, Sanna; Turgeon, Robert; Zhang, Cankui
2016-04-01
Despite the crucial role of carbon transport in whole plant physiology and its impact on plant-environment interactions and ecosystem function, relatively little research has tried to examine how phloem physiology impacts plant ecology. In this review, we highlight several areas of active research where inquiry into phloem physiology has increased our understanding of whole plant function and ecological processes. We consider how xylem-phloem interactions impact plant drought tolerance and reproduction, how phloem transport influences carbon allocation in trees and carbon cycling in ecosystems and how phloem function mediates plant relations with insects, pests, microbes and symbiotes. We argue that in spite of challenges that exist in studying phloem physiology, it is critical that we consider the role of this dynamic vascular system when examining the relationship between plants and their biotic and abiotic environment. © 2015 John Wiley & Sons Ltd.
Bacterial Symbionts in Lepidoptera: Their Diversity, Transmission, and Impact on the Host
Paniagua Voirol, Luis R.; Frago, Enric; Kaltenpoth, Martin; Hilker, Monika; Fatouros, Nina E.
2018-01-01
The insect’s microbiota is well acknowledged as a “hidden” player influencing essential insect traits. The gut microbiome of butterflies and moths (Lepidoptera) has been shown to be highly variable between and within species, resulting in a controversy on the functional relevance of gut microbes in this insect order. Here, we aim to (i) review current knowledge on the composition of gut microbial communities across Lepidoptera and (ii) elucidate the drivers of the variability in the lepidopteran gut microbiome and provide an overview on (iii) routes of transfer and (iv) the putative functions of microbes in Lepidoptera. To find out whether Lepidopterans possess a core gut microbiome, we compared studies of the microbiome from 30 lepidopteran species. Gut bacteria of the Enterobacteriaceae, Bacillaceae, and Pseudomonadaceae families were the most widespread across species, with Pseudomonas, Bacillus, Staphylococcus, Enterobacter, and Enterococcus being the most common genera. Several studies indicate that habitat, food plant, and age of the host insect can greatly impact the gut microbiome, which contributes to digestion, detoxification, or defense against natural enemies. We mainly focus on the gut microbiome, but we also include some examples of intracellular endosymbionts. These symbionts are present across a broad range of insect taxa and are known to exert different effects on their host, mostly including nutrition and reproductive manipulation. Only two intracellular bacteria genera (Wolbachia and Spiroplasma) have been reported to colonize reproductive tissues of Lepidoptera, affecting their host’s reproduction. We explore routes of transmission of both gut microbiota and intracellular symbionts and have found that these microbes may be horizontally transmitted through the host plant, but also vertically via the egg stage. More detailed knowledge about the functions and plasticity of the microbiome in Lepidoptera may provide novel leads for the control of lepidopteran pest species. PMID:29636736
Lin, Xinda; Yao, Yun; Wang, Bo; Emlen, Douglas J; Lavine, Laura Corley
2016-01-01
Crowding and changes in food availability are two critical environmental conditions that impact an animal's trajectory toward either migration or reproduction. Many insects facing this challenge have evolved wing polyphenisms. When conditions favor reproduction, wing polyphenic species produce adults that either have no wings or short, non-functional wings. Facultative wing growth reflects a physiological and evolutionary trade-off between migration and reproduction, triggered by environmental conditions. How environmental cues are transduced to produce these alternative forms, and their associated ecological shift from migration to reproduction, remains an important unsolved problem in evolutionary ecology. The brown planthopper, a wing polymorphic insect exhibiting strong trade-offs in investment between migration and reproduction, is one of the most serious rice pests in Asia. In this study, we investigated the function of four genes in the insulin-signaling pathway known to couple nutrition with growth, PI3 Kinase (PI3K), PDK1, Akt (Protein Kinase B), and the forkhead gene FOXO. Using a combination of RNA interference and pharmacological inhibitor treatment, we show that all four genes contribute to tissue level regulation of wing polymorphic development in this insect. As predicted, silencing of the NlPI3K, NlAkt and NlPDK1 through dsRNA and with the pharmacological inhibitor Perifosine resulted in short-winged brown planthoppers, whereas knockdown of NlFOXO resulted in long-winged planthoppers. Morphometric analyses confirm that phenotypes from our manipulations mimic what would be found in nature, i.e., major parameters such as bristle number, wing area and body weight are not significantly different from non-experimental animals. Taken together, these data implicate the insulin-signaling pathway in the transduction of environmental factors into condition-dependent patterns of wing growth in insects.
Dursun, Polat; Doğan, N Utku; Ayhan, Ali
2014-12-01
About ten percent of all female cancer survivors is younger than 40 years of age. For these young women the primary goal is to ensure the highest possibility of cure and to maintain the reproductive functions as well. Oncofertility is a new concept including both oncology and reproductive medicine. By this recently defined concept young women will have maximal chance to make an optimal decision without any significant impact and delay in oncologic outcome. Oncofertility concept could be applied for genital cancer as well as non-genital cancer of reproductive age. Currently sperm and embryo banking are the standard methods used for young patients with cancer whose future fertility is under risk. In contrary oocyte banking, ovarian tissue cryopreservation are all controversial procedures and still accepted as experimental by many authors although American Society of Reproductive Medicine (ASRM) consideres oocyte cryopreservation "no longer experimental". For genital cancers procedures for oncofertility depends on the type of the cancer and the treatment of choice. In this review the current data and concepts regarding oncofertility concept including the gynecologic oncologic perspective is reviewed. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
El-Kassaby, Yousry A; Funda, Tomas; Lai, Ben S K
2010-01-01
The impact of female reproductive success on the mating system, gene flow, and genetic diversity of the filial generation was studied using a random sample of 801 bulk seed from a 49-clone Pseudotsuga menziesii seed orchard. We used microsatellite DNA fingerprinting and pedigree reconstruction to assign each seed's maternal and paternal parents and directly estimated clonal reproductive success, selfing rate, and the proportion of seed sired by outside pollen sources. Unlike most family array mating system and gene flow studies conducted on natural and experimental populations, which used an equal number of seeds per maternal genotype and thus generating unbiased inferences only on male reproductive success, the random sample we used was a representative of the entire seed crop; therefore, provided a unique opportunity to draw unbiased inferences on both female and male reproductive success variation. Selfing rate and the number of seed sired by outside pollen sources were found to be a function of female fertility variation. This variation also substantially and negatively affected female effective population size. Additionally, the results provided convincing evidence that the use of clone size as a proxy to fertility is questionable and requires further consideration.
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.
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 and the current strategies to preserve their fertility in the light of the most recent evidence-based findings of the clinical trials and molecular studies.
Contu, Laura; Hawkes, Cheryl A
2017-05-19
Globally, more than 20% of women of reproductive age are currently estimated to be obese. Children born to obese mothers are at higher risk of developing obesity, coronary heart disease, diabetes, stroke, and asthma in adulthood. Increasing clinical and experimental evidence suggests that maternal obesity also affects the health and function of the offspring brain across the lifespan. This review summarizes the current findings from human and animal studies that detail the impact of maternal obesity on aspects of learning, memory, motivation, affective disorders, attention-deficit hyperactivity disorder, autism spectrum disorders, and neurodegeneration in the offspring. Epigenetic mechanisms that may contribute to this mother-child interaction are also discussed.
Warren, Charlotte; Abuya, Timothy; Obare, Francis; Sunday, Joseph; Njue, Rebecca; Askew, Ian; Bellows, Ben
2011-03-23
Alternatives to the traditional 'supply-side' approach to financing service delivery are being explored. These strategies are termed results-based finance, demand-side health financing or output-based aid which includes a range of interventions that channel government or donor subsidies to the user rather than the provider. Initial pilot assessments of reproductive health voucher programs suggest that, they can increase access and use, reducing inequities and enhancing program efficiency and service quality. However, there is a paucity of evidence describing how the programs function in different settings, for various reproductive health services. Population Council, funded by the Bill and Melinda Gates Foundation, intends to generate evidence around the 'voucher and accreditation' approaches to improving the reproductive health of low income women in Kenya. A quasi-experimental study will investigate the impact of the voucher approach on improving reproductive health behaviors, reproductive health status and reducing inequities at the population level; and assessing the effect of vouchers on increasing access to, and quality of, and reducing inequities in the use of selected reproductive health services. The study comprises of four populations: facilities, providers, women of reproductive health age using facilities and women and men who have been pregnant and/or used family planning within the previous 12 months. The study will be carried out in samples of health facilities - public, private and faith-based in: three districts; Kisumu, Kiambu, Kitui and two informal settlements in Nairobi which are accredited to provide maternal and newborn health and family planning services to women holding vouchers for the services; and compared with a matched sample of non-accredited facilities. Health facility assessments (HFA) will be conducted at two stages to track temporal changes in quality of care and utilization. Facility inventories, structured observations, and client exit interviews will be used to collect comparable data across facilities. Health providers will also be interviewed and observed providing care. A population survey of about 3000 respondents will also be carried out in areas where vouchers are distributed and similar locations where vouchers are not distributed.
Animal models of physiologic markers of male reproduction: genetically defined infertile mice
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chubb, C.
The present report focuses on novel animal models of male infertility: genetically defined mice bearing single-gene mutations that induce infertility. The primary goal of the investigations was to identify the reproductive defects in these mutant mice. The phenotypic effects of the gene mutations were deciphered by comparing the mutant mice to their normal siblings. Initially testicular steroidogenesis and spermatogenesis were investigated. The physiologic markers for testicular steroidogenesis were steroid secretion by testes perifused in vitro, seminal vesicle weight, and Leydig cell histology. Spermatogenesis was evaluated by the enumeration of homogenization-resistant sperm/spermatids in testes and by morphometric analyses of germ cellsmore » in the seminiferous epithelium. If testicular function appeared normal, the authors investigated the sexual behavior of the mice. The parameters of male sexual behavior that were quantified included mount patency, mount frequency, intromission latency, thrusts per intromission, ejaculation latency, and ejaculation duration. Females of pairs breeding under normal circumstances were monitored for the presence of vaginal plugs and pregnancies. The patency of the ejaculatory process was determined by quantifying sperm in the female reproductive tract after sexual behavior tests. Sperm function was studied by quantitatively determining sperm motility during videomicroscopic observation. Also, the ability of epididymal sperm to function within the uterine environment was analyzed by determining sperm capacity to initiate pregnancy after artificial insemination. Together, the experimental results permitted the grouping of the gene mutations into three general categories. They propose that the same biological markers used in the reported studies can be implemented in the assessment of the impact that environmental toxins may have on male reproduction.« less
Kues, Johanna N; Janda, Carolyn; Kleinstäuber, Maria; Weise, Cornelia
2016-10-01
With 75% of women of reproductive age affected, premenstrual symptoms are very common, ranging from emotional and cognitive to physical symptoms. Premenstrual Syndrome and Premenstrual Dysphoric Disorder can lead to substantial functional interference and psychological distress comparable to that of dysthymic disorders. The assessment of this impact is required as a part of the diagnostic procedure in the DSM-5. In the absence of a specific measure, the authors developed the PMS-Impact Questionnaire. A sample of 101 women reporting severe premenstrual complaints was assessed with the twenty-two items in the questionnaire during their premenstrual phase in an ongoing intervention study at the Philipps-University Marburg from August 2013 until January 2015. An exploratory factor analysis revealed a two-factor solution (labeled Psychological Impact and Functional Impact) with 18 items. A Cronbach's alpha of 0.90 for Psychological Impact and of 0.90 for Functional Impact indicated good reliability. Convergent construct validity was demonstrated by moderate to high correlations with the Pain Disability Index. Low correlations with the Big Five Inventory-10 indicated good divergent validity. The PMS-Impact Questionnaire was found to be a valid, reliable, and an economic measure to assess the impact of premenstrual symptoms. In future research, cross validations and confirmatory factor analyses should be conducted.
[Advances in the study of neuroendocrinological regulation of kisspeptin in fish reproduction].
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.
Ovarian and Uterine Functions in Female Survivors of Childhood Cancers.
Oktem, Ozgur; Kim, Samuel S; Selek, Ugur; Schatmann, Glenn; Urman, Bulent
2018-02-01
Adult survivors of childhood cancers are more prone to developing poor reproductive and obstetrical outcomes than their siblings and the general population as a result of previous exposure to chemotherapy and radiation during childhood. Chemotherapy drugs exert cytotoxic effects systemically and therefore can damage the ovaries, leading to infertility, premature ovarian failure, and, to a lesser extent, spontaneous abortions. They have very limited or no deleterious effects on the uterus that can be recognized clinically. By contrast, radiation is detrimental to both the ovaries and the uterus, thereby causing a greater magnitude of adverse effects on the female reproductive function. These include infertility, premature ovarian failure, miscarriage, fetal growth restrictions, perinatal deaths, preterm births, delivery of small-for-gestational-age infants, preeclampsia, and abnormal placentation. Regrettably, the majority of these adverse outcomes arise from radiation-induced uterine injury and are reported at higher incidence in the adult survivors of childhood cancers who were exposed to uterine radiation during childhood in the form of pelvic, spinal, or total-body irradiation. Recent findings of long-term follow-up studies evaluating reproductive performance of female survivors provided some reassurance to female cancer survivors by documenting that pregnancy and live birth rates were not significantly compromised in survivors, including those who had been treated with alkylating agents and had not received pelvic, cranial, and total-body irradiation. We aimed in this narrative review article to provide an update on the impact of chemotherapy and radiation on the ovarian and uterine function in female survivors of childhood cancer. Adult survivors of childhood cancers are more prone to developing a number of poor reproductive and obstetrical outcomes than their siblings and the general population as a result of previous exposure to chemotherapy and radiation during childhood. The impact of radiation therapy on the female genital system is greater than chemotherapy regimens because radiation is detrimental to both the uterus and the ovaries, whereas toxic effects of chemotherapy drugs are confined to the ovaries. Therefore, radiation-induced uterine damage accounts for most poor obstetrical outcomes in the survivors. These include infertility, miscarriages, stillbirths, fetal growth restrictions, preeclampsia, and preterm deliveries. © AlphaMed Press 2017.
Surrogate obesity negatively impacts pregnancy rates in third-party reproduction.
DeUgarte, Daniel A; DeUgarte, Catherine M; Sahakian, Vicken
2010-02-01
In a retrospective cohort review of third-party reproduction, we observed that surrogate body mass index (BMI) negatively impacts implantation rates in oocyte-donor in vitro fertilization cycles. A BMI > or =35 kg/m(2) cutoff is associated with a statistically significant decrease in pregnancy rates but not miscarriage rates. Copyright 2010 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.
Programs to improve adolescent sexual and reproductive health in the US: a review of the evidence.
Manlove, Jennifer; Fish, Heather; Moore, Kristin Anderson
2015-01-01
US adolescents have high rates of teen pregnancy, childbearing, and sexually transmitted infections (STIs), highlighting the need to identify and implement effective programs that will help improve teen sexual and reproductive health. This review identified 103 random-assignment evaluations of 85 programs that incorporated intent-to-treat analyses and assessed impacts on pregnancy, childbearing, STIs, and their key determinants - sexual activity, number of sexual partners, condom use, and other contraceptive use - among teens. This review describes the evidence base for five broad program approaches, including abstinence education, comprehensive sex education, clinic-based programs, youth development programs, and parent-youth relationship programs. We also describe programs with impacts on key outcomes, including pregnancy/childbearing, STIs, and those that found impacts on both sexual activity and contraceptive use. Our review identified 52 effective programs: 38 with consistent impacts on reproductive health outcomes, and 14 with mixed findings (across subpopulations, follow-ups, or multiple measures of a single outcome). We found that a variety of program approaches produced impacts on sexual and reproductive health outcomes. Parent-youth relationship programs and clinic-based program evaluations more frequently showed impacts than other program approaches, although we also identified a number of abstinence-education, comprehensive sex education, and youth-development programs with impacts on sexual and reproductive health outcomes. Overall, we identified nine program evaluations with impacts on teen pregnancies or births, five with impacts on reducing STIs, and 15 with impacts on both delaying/reducing sexual activity and increasing contraceptive use (including condom use). Future efforts should conduct replications of existing program evaluations, identify implementation components linked to impacts, rigorously evaluate programs that appear promising, and expand the evidence base on programs that impact hormonal and long-acting contraceptive method use.
Surgical Management of Neurovascular Bundle in Uterine Fibroid Pseudocapsule
Malvasi, Antonio; Hurst, Brad S.; Tsin, Daniel A.; Davila, Fausto; Dominguez, Guillermo; Dell'edera, Domenico; Cavallotti, Carlo; Negro, Roberto; Gustapane, Sarah; Teigland, Chris M.; Mettler, Liselotte
2012-01-01
The uterine fibroid pseudocapsule is a fibro-neurovascular structure surrounding a leiomyoma, separating it from normal peripheral myometrium. The fibroid pseudocapsule is composed of a neurovascular network rich in neurofibers similar to the neurovascular bundle surrounding a prostate. The nerve-sparing radical prostatectomy has several intriguing parallels to myomectomy. It may serve either as a useful model in modern fibroid surgical removal, or it may accelerate our understanding of the role of the fibrovascular bundle and neurotransmitters in the healing and restoration of reproductive potential after intracapsular myomectomy. Surgical innovations, such as laparoscopic or robotic myomectomy applied to the intracapsular technique with magnification of the fibroid pseudocapsule surrounding a leiomyoma, originated from the radical prostatectomy method that highlighted a careful dissection of the neurovascular bundle to preserve sexual functioning after prostatectomy. Gentle uterine leiomyoma detachment from the pseudocapsule neurovascular bundle has allowed a reduction in uterine bleeding and uterine musculature trauma with sparing of the pseudocapsule neuropeptide fibers. This technique has had a favorable impact on functionality in reproduction and has improved fertility outcomes. Further research should determine the role of the myoma pseudocapsule neurovascular bundle in the formation, growth, and pathophysiological consequences of fibroids, including pain, infertility, and reproductive outcomes. PMID:22906340
Full-scale system impact analysis: Digital document storage project
NASA Technical Reports Server (NTRS)
1989-01-01
The Digital Document Storage Full Scale System can provide cost effective electronic document storage, retrieval, hard copy reproduction, and remote access for users of NASA Technical Reports. The desired functionality of the DDS system is highly dependent on the assumed requirements for remote access used in this Impact Analysis. It is highly recommended that NASA proceed with a phased, communications requirement analysis to ensure that adequate communications service can be supplied at a reasonable cost in order to validate recent working assumptions upon which the success of the DDS Full Scale System is dependent.
Emerging roles for neurosteroids in sexual behavior and function.
King, Steven R
2008-01-01
Although gonadal and adrenal steroids heavily impact sexual function at the level of the brain, the nervous system also produces its own steroids de novo that may regulate sexual behavior and reproduction. Current evidence points to important roles for neurosteroids in sexual and gender-typical behaviors, control of ovulation, and behaviors that strongly influence sexual interest and motivation like aggression, anxiety and depression. At the cellular level, neurosteroids act through stimulating rapid changes in excitability and direct activation of membrane receptors in neurons. Thus, unlike peripheral steroids, neurosteroids can have immediate and specific effects on select neuronal pathways to regulate sexual function.
Ma, Qiang; Huang, Hui; Sun, Long; Zhou, Tong; Zhu, Jingyuan; Cheng, Xuemin; Duan, Lijv; Li, Zhiyuan; Cui, Liuxin; Ba, Yue
2017-12-01
The occurrence of endemic fluorosis is derived from high fluoride levels in drinking water and industrial fumes or dust. Reproductive disruption is also a major harm caused by fluoride exposure besides dental and skeletal lesions. However, few studies focus on the mechanism of fluoride exposure on male reproductive function, especially the possible interaction of fluoride exposure and gene polymorphism on male reproductive hormones. Therefore, we conducted a cross-sectional study in rural areas of Henan province in China to explore the interaction between the estrogen receptor alpha (ERα) gene and fluoride exposure on reproductive hormone levels in male farmers living in the endemic fluorosis villages. The results showed that fluoride exposure significantly increased the serum level of estradiol in the hypothalamic-pituitary-testicular (HPT) axis in male farmers. Moreover, the observations indicated that fluoride exposure and genetic markers had an interaction on serum concentration of follicle-stimulating hormone and estradiol, and the interaction among different loci of the ERα gene could impact the serum testosterone level. Findings in the present work suggest that chronic fluoride exposure in drinking water could modulate the levels of reproductive hormones in males living in endemic fluorosis areas, and the interaction between fluoride exposure and ERα polymorphisms might affect the serum levels of hormones in the HPT axis in male farmers. Copyright © 2017 Elsevier Ltd. All rights reserved.
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.
Genome-Wide Mapping of Loci Explaining Variance in Scrotal Circumference in Nellore Cattle
Utsunomiya, Yuri T.; Carmo, Adriana S.; Neves, Haroldo H. R.; Carvalheiro, Roberto; Matos, Márcia C.; Zavarez, Ludmilla B.; Ito, Pier K. R. K.; Pérez O'Brien, Ana M.; Sölkner, Johann; Porto-Neto, Laercio R.; Schenkel, Flávio S.; McEwan, John; Cole, John B.; da Silva, Marcos V. G. B.; Van Tassell, Curtis P.; Sonstegard, Tad S.; Garcia, José Fernando
2014-01-01
The reproductive performance of bulls has a high impact on the beef cattle industry. Scrotal circumference (SC) is the most recorded reproductive trait in beef herds, and is used as a major selection criterion to improve precocity and fertility. The characterization of genomic regions affecting SC can contribute to the identification of diagnostic markers for reproductive performance and uncover molecular mechanisms underlying complex aspects of bovine reproductive biology. In this paper, we report a genome-wide scan for chromosome segments explaining differences in SC, using data of 861 Nellore bulls (Bos indicus) genotyped for over 777,000 single nucleotide polymorphisms. Loci that excel from the genome background were identified on chromosomes 4, 6, 7, 10, 14, 18 and 21. The majority of these regions were previously found to be associated with reproductive and body size traits in cattle. The signal on chromosome 14 replicates the pleiotropic quantitative trait locus encompassing PLAG1 that affects male fertility in cattle and stature in several species. Based on intensive literature mining, SP4, MAGEL2, SH3RF2, PDE5A and SNAI2 are proposed as novel candidate genes for SC, as they affect growth and testicular size in other animal models. These findings contribute to linking reproductive phenotypes to gene functions, and may offer new insights on the molecular biology of male fertility. PMID:24558400
The long-term effects of the Holocaust on the reproductive function of female survivors.
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.
Challenging cell phone impact on reproduction: a review.
Merhi, Zaher O
2012-04-01
The radiofrequency electromagnetic radiation (RF-EMR) produced by cell phones can enhance the excitability of the brain and has recently been classified as carcinogenic. The suggested use of hands-free kits lowers the exposure to the brain, but it might theoretically increase exposure to the reproductive organs. This report summarizes the potential effects of RF-EMR on reproductive potentials in both males and females. A critical review of the literature pertaining to the impact of cell phone RF-EMR on reproduction in male and female animals and humans was performed, with a focus on gonad metabolism, apoptosis of reproductive cells, fertility status, and serum reproductive hormones. While some animal and human studies revealed alterations in reproductive physiology in both males and females, others did not report any association. The in vitro and in vivo studies to date are highly diverse, very inconsistent in conduct and, in many cases, report different primary outcomes. The increasing use of cell phone warrants well-designed studies to ascertain the effect of their RF-EMR on reproduction.
de Jong, Laetitia; Pech, Nicolas; de Aragão Umbuzeiro, Gisela; Moreau, Xavier
2016-06-01
Acute (24 h, 48 h, 72 h) and chronic (7 days) tests have been performed to evaluate the effects of the commercial azo dye Disperse Red 1 (DR1) using various biomarkers in the freshwater invertebrate Hydra attenuata. Morphological changes have been selected to calculate ecotoxicological thresholds for sublethal and lethal DR1 concentrations. A multinomial logistic model showed that the probability of each morphological stage occurrence was function of concentration, time and interaction between both. Results of oxidative balance parameter measurements (72 h and 7 days) suggest that polyps set up defense mechanisms to limit lipid peroxidation caused by DR1. DR1 exposure at hormetic concentrations induces increase of asexual reproductive rates. This result suggests (1) an impact on the fitness-related phenotypical traits and (2) trade-offs between reproduction and maintenance to allow the population to survive harsher conditions. Changes in serotonin immuno-labeling in polyps showing alterations in feeding behavior suggest that chronic DR1 exposure impaired neuronal processes related to ingesting behavior in H. attenuata. This ecotoxicity study sheds light on the possible serotonin function in Hydra model and reports for the first time that serotonin could play a significant role in feeding behavior. This study used a multi-scale biomarker approach investigating biochemical, morphological, reproductive and behavioral endpoints in Hydra attenuata. This organism is proposed for a pertinent animal model to assess ecotoxicological impact of pollutant mixtures in freshwater environment. Copyright © 2016 Elsevier Ltd. All rights reserved.
Potential negative effects of anti-histamines on male reproductive function.
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.
2011-01-01
Background Cost of delivering reproductive health services to low income populations will always require total or partial subsidization by government and/or development partners. Broadly termed "demand-side financing" or "output-based aid", these strategies include a range of interventions that channel government or donor subsidies to the user rather than the service provider. Initial pilot assessments of reproductive health voucher programs suggest that they can increase access, reduce inequities, and enhance program efficiency and service quality. However, there is a paucity of evidence describing how these programs function in different settings for various reproductive health services. Methods/Design Population Council, funded by the Bill and Melinda Gates Foundation, intends to generate evidence around the "voucher and accreditation" approaches to improving the reproductive health of low-income women in Cambodia. The study comprises of four populations: facilities, providers, women of reproductive age using facilities, and women and men who have been pregnant and/or used family planning within the previous 12 months. The study will be carried out in a sample of 20 health facilities that are accredited to provide maternal and newborn health and family planning services to women holding vouchers from operational districts in three provinces: Kampong Thom, Kampot and Prey Veng and a matched sample of non-accredited facilities in three other provinces. Health facility assessments will be conducted at baseline and endline to track temporal changes in quality-of-care, client out-of-pocket costs, and utilization. Facility inventories, structured observations, and client exit interviews will be used to collect comparable data across facilities. Health providers will also be interviewed and observed providing care. A population survey of about 3000 respondents will also be conducted in areas where vouchers are distributed and similar non-voucher locations. Discussion A quasi-experimental study will investigate the impact of the voucher approach on improving reproductive health behaviors, reproductive health status and reducing inequities at the population level and assess effects on access, equity and quality of care at the facility level. If the voucher scheme in Cambodia is found effective, it may help other countries adopt this approach for improving utilization and access to reproductive health and family planning services. PMID:21864405
Myomas and Adenomyosis: Impact on Reproductive Outcome.
Vlahos, Nikos F; Theodoridis, Theodoros D; Partsinevelos, George A
2017-01-01
Among uterine structural abnormalities, myomas and adenomyosis represent two distinct, though frequently coexistent entities, with a remarkable prevalence in women of reproductive age. Various mechanisms have been proposed to explain the impact of each of them on reproductive outcome. In respect to myomas, current evidence implies that submucosal ones have an adverse effect on conception and early pregnancy. A similar effect yet is not quite clear and has been suggested for intramural myomas. Still, it seems reasonable that intramural myomas greater than 4 cm in diameter may negatively impair reproductive outcome. On the contrary, subserosal myomas do not seem to have a significant impact, if any, on reproduction. The presence of submucosal and/or large intramural myomas has also been linked to adverse pregnancy outcomes. In particular increased risk for miscarriage, fetal malpresentation, placenta previa, preterm birth, placenta abruption, postpartum hemorrhage, and cesarean section has been reported. With regard to adenomyosis, besides the tentative coexistence of adenomyosis and infertility, to date a causal relationship among these conditions has not been fully confirmed. Preterm birth and preterm premature rupture of membranes, uterine rupture, postpartum hemorrhage due to uterine atony, and ectopic pregnancy have all been reported in association with adenomyosis. Further research on the impact of adenomyosis on reproductive outcome is welcome.
Myomas and Adenomyosis: Impact on Reproductive Outcome
Vlahos, Nikos F.; Theodoridis, Theodoros D.
2017-01-01
Among uterine structural abnormalities, myomas and adenomyosis represent two distinct, though frequently coexistent entities, with a remarkable prevalence in women of reproductive age. Various mechanisms have been proposed to explain the impact of each of them on reproductive outcome. In respect to myomas, current evidence implies that submucosal ones have an adverse effect on conception and early pregnancy. A similar effect yet is not quite clear and has been suggested for intramural myomas. Still, it seems reasonable that intramural myomas greater than 4 cm in diameter may negatively impair reproductive outcome. On the contrary, subserosal myomas do not seem to have a significant impact, if any, on reproduction. The presence of submucosal and/or large intramural myomas has also been linked to adverse pregnancy outcomes. In particular increased risk for miscarriage, fetal malpresentation, placenta previa, preterm birth, placenta abruption, postpartum hemorrhage, and cesarean section has been reported. With regard to adenomyosis, besides the tentative coexistence of adenomyosis and infertility, to date a causal relationship among these conditions has not been fully confirmed. Preterm birth and preterm premature rupture of membranes, uterine rupture, postpartum hemorrhage due to uterine atony, and ectopic pregnancy have all been reported in association with adenomyosis. Further research on the impact of adenomyosis on reproductive outcome is welcome. PMID:29234680
Brekke, Patricia; Ewen, John G; Clucas, Gemma; Santure, Anna W
2015-01-01
Floating males are usually thought of as nonbreeders. However, some floating individuals are able to reproduce through extra-pair copulations. Floater reproductive success can impact breeders’ sex ratio, reproductive variance, multiple paternity and inbreeding, particularly in small populations. Changes in reproductive variance alter the rate of genetic drift and loss of genetic diversity. Therefore, genetic management of threatened species requires an understanding of floater reproduction and determinants of floating behaviour to effectively conserve species. Here, we used a pedigreed, free-living population of the endangered New Zealand hihi (Notiomystis cincta) to assess variance in male reproductive success and test the genetic (inbreeding and heritability) and conditional (age and size) factors that influence floater behaviour and reproduction. Floater reproduction is common in this species. However, floater individuals have lower reproductive success and variance in reproductive success than territorial males (total and extra-pair fledglings), so their relative impact on the population's reproductive performance is low. Whether an individual becomes a floater, and if so then how successful they are, is determined mainly by individual age (young and old) and to lesser extents male size (small) and inbreeding level (inbred). Floating males have a small, but important role in population reproduction and persistence of threatened populations. PMID:26366197
In response to legislation, the USEPA is developing assessment tools for identifying chemicals likely to cause sublethal effects on reproduction and reproductive development with ultimate adverse impacts on fish populations. While fecundity and fertility data from short-term adul...
Human reproductive issues in space
NASA Technical Reports Server (NTRS)
Santy, Patricia A.; Jennings, Richard T.
1992-01-01
A review of reproductive functioning in animal species studied during space flight demonstrated that most species were affected significantly by the absence of gravity and/or the presence of radiation. These two factors induced alterations in normal reproductive functioning independently of, as well as in combination with, each other. Based on animal models, several potential problem areas regarding human reproductive physiology and functioning in the space environment were identified. While there are no current space flight investigations, the animal studies suggest priorities for future research in human reproduction. Such studies will be critical for the successful colonization of the space frontier.
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.
Frontiers in Reproduction (FIR): An Assessment of Success1
Ascoli, Mario; Mebane, Dorianne; Fazleabas, Asgerally T.
2016-01-01
The Frontiers in Reproduction (FIR) course has been held annually since 1998 at the Marine Biological Laboratories in Woods Hole, MA. The primary purpose of the course is to train young reproductive biologists in cutting-edge techniques that would strengthen their career opportunities. An initial evaluation of the FIR course was conducted by surveying the participants who took the course between 1998 and 2002. The findings of this survey were published in Biology of Reproduction in 2006, which highlighted the overall positive impact the course had on the training and upward career trajectory of the participants during the first 5 yr. The current study was designed to access the continued impact of FIR at the 10-yr mark by evaluating the participants who took the course between 1998 and 2008 using two different survey mechanisms. Based on these evaluations and feedback from the participants, it was evident that 1) FIR continues to have a significant positive impact on the careers of the participants, 2) the majority of the participants continue to be involved in research or administration related to the reproductive sciences, 3) nearly 90% of the attendees have been successful in obtaining funding for their research, and 4) most alumni have published at least five manuscripts in higher impact journals since they took the course. Therefore, it is evident that FIR participants are highly successful and continue to significantly impact the advances in the reproductive sciences worldwide. PMID:27335071
The influence of habitat fragmentation on multiple plant-animal interactions and plant reproduction.
Brudvig, Lars A; Damschen, Ellen I; Haddad, Nick M; Levey, Douglas J; Tewksbury, Joshua J
2015-10-01
Despite broad recognition that habitat loss represents the greatest threat to the world's biodiyersity, a mechanistic understanding of how habitat loss and associated fragmentation affect ecological systems has proven remarkably challenging. The challenge stems from the multiple interdependent ways that landscapes change following fragmentation and the ensuing complex impacts on populations and communities of interacting species. We confronted these challenges by evaluating how fragmentation affects individual plants through interactions with animals, across five herbaceous species native to longleaf pine savannas. We created a replicated landscape experiment that provides controlled tests of three major fragmentation effects (patch isolation, patch shape [i.e., edge-to-area ratio], and distance to edge), established experimental founder populations of the five species to control for spatial distributions and densities of individual plants, and employed structural equation modeling to evaluate the effects of fragmentation on plant reproductive output and the degree to which these impacts are mediated through altered herbivory, pollination, or pre-dispersal seed predation. Across species, the most consistent response to fragmentation was a reduction in herbivory. Herbivory, however, had little impact.on plant reproductive output, and thus we found little evidence for any resulting benefit to plants in fragments. In contrast, fragmentation rarely impacted pollination or pre-dispersal seed predation, but both of these interactions had strong and consistent impacts on plant reproductive output. As a result, our models robustly predicted plant reproductive output (r2 = 0.52-0.70), yet due to the weak effects of fragmentation on pollination and pre-dispersal seed predation, coupled with the weak effect of herbivory on plant reproduction, the effects of fragmentation on reproductive output were generally small in magnitude and inconsistent. This work provides mechanistic insight into landscape-scale variation in plant reproductive success, the relative importance of plant-animal interactions for structuring these dynamics, and the nuanced nature of how habitat fragmentation can affect populations and communities of interacting species.
Polymorphisms in JMJD1C are associated with pubertal onset in boys and reproductive function in men.
Mørup, Nina; Busch, Alexander Siegfried; Bang, Anne Kirstine; Nordkap, Loa; Nielsen, John E; Rajpert-De Meyts, Ewa; Juul, Anders; Jørgensen, Niels; Almstrup, Kristian
2017-12-08
JMJD1C, a member of the Jumonji-domain containing histone demethylases protein family, has been associated with levels of sex-hormone binding globulin (SHBG) and testosterone in men, and knock-out rodent models show age-dependent infertility. The objective of this study was to investigate whether single nucleotide polymorphisms (SNPs) nearby JMJD1C are associated with pubertal onset in boys and with male reproduction. 671 peri-pubertal boys, 1,027 young men, 315 fertile men, and 252 infertile men were genotyped for two JMJD1C SNPs (rs7910927 and rs10822184). rs7910927 and rs10822184 showed high linkage. Boys with the rs7910927 TT genotype entered puberty 3.6 months earlier than their peers (p = 2.5 × 10 -2 ). In young men, the number of T alleles was associated with decreased levels of SHBG, follicle-stimulating hormone (FSH), testosterone, and testosterone x luteinizing hormone, as well as increased levels of Inhibin B, Inhibin B/FSH ratio, and testis size. No significant associations with semen parameters were observed and the genotype distribution was comparable among fertile and infertile men. In conclusion, genetic variation in the vicinity of JMJD1C had a surprisingly large impact on the age at pubertal onset in boys as well as levels of reproductive hormones and testis size in men, emphasizing the relationship between JMJD1C and reproductive functions.
Perceived stress, reproductive hormones, and ovulatory function: a prospective cohort study
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
Alavi, Yasaman; Elgar, Mark Adrian; Jones, Therésa Melanie
2017-07-01
Facultative parthenogenetic species, in which females can alternate between sex and parthenogenesis, are useful models to investigate the costs and benefits of sex and parthenogenesis, an ongoing issue in biology. The necessary empirical studies comparing the outcomes of alternative reproductive modes on life history traits are rare and focus mainly on traits directly associated with reproductive fitness. Immune function determines the ability of individuals to defend themselves against injury and disease and is therefore likely to have a significant impact on fitness. Here, we used the facultatively parthenogenetic Australian phasmatid, Extatosoma tiaratum, to investigate the effect of both maternal and offspring mode of conception (sexual or parthenogenetic) on offspring immune function (haemocyte concentration, lytic activity and phenoloxidase activity). We show that when parthenogenesis persists beyond one generation, it has negative effects on immune response in terms of haemocyte concentration and lytic activity. Phenoloxidase activity positively correlates with the level of microsatellite heterozygosity. Moreover, immune response decreases across consecutive sampling weeks, suggesting there are physiological constraints with respect to mounting immune responses in close time intervals. Copyright © 2017 Elsevier Ltd. All rights reserved.
Chapter 11.18 - Neuroendocrine Control of Female Reproduction.
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 ...
Impacts of trapping adult roseate terns on their reproductive success
Zingo, James M.; Field, R.; Spendelow, J.A.
1996-01-01
Although Roseate Terns (Sterna dougallii) habituate to many research activities, the trapping and temporary removal of one of both members of a nesting pair may affect their annual and lifetime reproductive success. Protocols for trapping adult Roseate Terns that reduce the chances of nest desertion, neglect of chicks, and injury to adults were developed in the early 1980s, but both shortterm and longterm impacts of research activities on this federally endangered species have not been fully investigated. Therefore, for this study we evaluated the impacts of trapping adult terns on their annual reproductive success. Although retrospective analysis of 18 years (1978-1995) of data from the Falkner Island colony site (McKinney NWR, Guilford, Connecticut) did not reveal correlations between measures of trapping effort and annual reproductive success, recent results of more detailed research suggest that Roseate Terns may be susceptible to trapping impacts when also faced with extreme conditions such as low food availability and/or high predatory pressure. These results indicate the need to consider local conditions when planning trapping activities and projecting the potential annual and possible longterm impacts.
Duffour, Jacqueline; Combes, Audrey; Crapez, Evelyne; Boissière-Michot, Florence; Bibeau, Frédéric; Senesse, Pierre; Ychou, Marc; Courraud, Julie; de Forges, Hélène; Roca, Lise
2016-06-01
Reproductive techniques such as prenatal diagnosis (PND) or preimplantation genetic diagnosis (PGD), although debated, are legally forbidden in France in case of Lynch syndrome. The preference of mutation carriers about their reproductive options is not systematically considered in France. We aimed to prospectively assess the reproductive preferences of mismatch repair mutation carriers consulting in our institution (2003-2010, n = 100). We also considered the short- and long-term post-disclosure psychological impact using the Impact of Events Scale-Revised questionnaire to measure the prevalence of posttraumatic stress disorder (PTSD) in those patients. Complete data were obtained for 34 respondents (17 males, 17 females, median age of 33.5 years [22-59]). Seventeen respondents (57 %) preferred spontaneous natural conception versus 28 % and 35 % choosing PND and PGD, respectively. At results disclosure, respondents mainly explained their distress by fear of premature death (43 %) and transmitting mutated genes (42 %). One year later, this last fear remained predominant in 55 % of subjects. None of the main socio-demographical, psychological or medical variables (including fear of transmitting mutations) was significantly associated with the reproductive preferences. Results disclosure had a real and time-decreasing psychological impact on mutation carriers. Reproductive techniques, expected to decrease the hereditary risk, were not significantly preferred to natural conception.
EGFR ligands exert diverging effects on male reproductive organs.
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.
[Causes and Factors of Male Infertility].
Kolesnikova, L I; Kolesnikov, S I; Kurashova, N A; Bairova, T A
2015-01-01
The preservation of reproductive health of the population is an important factor of demographic policy of the state. According to some authors from 14 to 30% of couples of reproductive age suffer from infertility, malefactor in such marriages is detected in more than half of the cases. As you know, in recent years there has been a significant deterioration in the main indicators of reproductive function of men. Increased the number of andrological diseases, morphological disorders of the male reproductive system, almost halved the production of sperm in men of reproductive age. The reason probably lies behind a whole range ofstressfactors, such as medical ignorance, uncontrolled and inappropriate use of medication, metabolic disturbances, lack of vitamins and minerals, the impact of industrial pollutants, as well as the growth of addictive disorders (alcoholism, smoking and drug addiction). The forms of infertility differ according to its etiology and severity from minor changes to complete spermatogenesis dysfunction of the gonads, and can also occur due to genetic disorders. The lack of analysis of the relationship between clinical and genetic-biochemical components in men with infertility makes it impossible to understand the pathogenesis of infertility and to assess the risks of male infertility. High level of current medicine does not always guarantee an identification of the cause of male infertility. The article analyzes data from the review of specialized literature on the diagnosis and etiopathogenesis of male infertility. Frequency and clinical signs of pathology of the male reproductive system depend on the combinatorial effects of environmental influences, manifested most often in mutually reinforcing effect. A combination of several, seemed to be imperceptible factors makes the risk of development of male reproductive pathology very high. This situation compels specialists to conduct comprehensive studies on the men reproductive potential.
Programs to improve adolescent sexual and reproductive health in the US: a review of the evidence
Manlove, Jennifer; Fish, Heather; Moore, Kristin Anderson
2015-01-01
Background US adolescents have high rates of teen pregnancy, childbearing, and sexually transmitted infections (STIs), highlighting the need to identify and implement effective programs that will help improve teen sexual and reproductive health. Materials and methods This review identified 103 random-assignment evaluations of 85 programs that incorporated intent-to-treat analyses and assessed impacts on pregnancy, childbearing, STIs, and their key determinants – sexual activity, number of sexual partners, condom use, and other contraceptive use – among teens. This review describes the evidence base for five broad program approaches, including abstinence education, comprehensive sex education, clinic-based programs, youth development programs, and parent–youth relationship programs. We also describe programs with impacts on key outcomes, including pregnancy/childbearing, STIs, and those that found impacts on both sexual activity and contraceptive use. Results Our review identified 52 effective programs: 38 with consistent impacts on reproductive health outcomes, and 14 with mixed findings (across subpopulations, follow-ups, or multiple measures of a single outcome). We found that a variety of program approaches produced impacts on sexual and reproductive health outcomes. Parent–youth relationship programs and clinic-based program evaluations more frequently showed impacts than other program approaches, although we also identified a number of abstinence-education, comprehensive sex education, and youth-development programs with impacts on sexual and reproductive health outcomes. Overall, we identified nine program evaluations with impacts on teen pregnancies or births, five with impacts on reducing STIs, and 15 with impacts on both delaying/reducing sexual activity and increasing contraceptive use (including condom use). Conclusion Future efforts should conduct replications of existing program evaluations, identify implementation components linked to impacts, rigorously evaluate programs that appear promising, and expand the evidence base on programs that impact hormonal and long-acting contraceptive method use. PMID:25897271
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
Indigenous peoples of North America: environmental exposures and reproductive justice.
Hoover, Elizabeth; Cook, Katsi; Plain, Ron; Sanchez, Kathy; Waghiyi, Vi; Miller, Pamela; Dufault, Renee; Sislin, Caitlin; Carpenter, David O
2012-12-01
Indigenous American communities face disproportionate health burdens and environmental health risks compared with the average North American population. These health impacts are issues of both environmental and reproductive justice. In this commentary, we review five indigenous communities in various stages of environmental health research and discuss the intersection of environmental health and reproductive justice issues in these communities as well as the limitations of legal recourse. The health disparities impacting life expectancy and reproductive capabilities in indigenous communities are due to a combination of social, economic, and environmental factors. The system of federal environmental and Indian law is insufficient to protect indigenous communities from environmental contamination. Many communities are interested in developing appropriate research partnerships in order to discern the full impact of environmental contamination and prevent further damage. Continued research involving collaborative partnerships among scientific researchers, community members, and health care providers is needed to determine the impacts of this contamination and to develop approaches for remediation and policy interventions.
Indigenous Peoples of North America: Environmental Exposures and Reproductive Justice
Cook, Katsi; Plain, Ron; Sanchez, Kathy; Waghiyi, Vi; Miller, Pamela; Dufault, Renee; Sislin, Caitlin; Carpenter, David O.
2012-01-01
Background: Indigenous American communities face disproportionate health burdens and environmental health risks compared with the average North American population. These health impacts are issues of both environmental and reproductive justice. Objectives: In this commentary, we review five indigenous communities in various stages of environmental health research and discuss the intersection of environmental health and reproductive justice issues in these communities as well as the limitations of legal recourse. Discussion: The health disparities impacting life expectancy and reproductive capabilities in indigenous communities are due to a combination of social, economic, and environmental factors. The system of federal environmental and Indian law is insufficient to protect indigenous communities from environmental contamination. Many communities are interested in developing appropriate research partnerships in order to discern the full impact of environmental contamination and prevent further damage. Conclusions: Continued research involving collaborative partnerships among scientific researchers, community members, and health care providers is needed to determine the impacts of this contamination and to develop approaches for remediation and policy interventions. PMID:22899635
van Arendonk, Johan A M; Bijma, Piter
2003-01-15
Reproductive techniques have a major impact on the structure of breeding programmes, the rate of genetic gain and dissemination of genetic gain in populations. This manuscript reviews the impact of reproductive technologies on the underlying components of genetic gain and inbreeding with special reference to the role of female reproductive technology. Evaluation of alternative breeding schemes should be based on genetic gain while constraining inbreeding. Optimum breeding schemes can be characterised by: decreased importance of sib information; increased accuracy at the expense of intensity; and a factorial mating strategy. If large-scale embryo cloning becomes feasible, this will have a small impact on the rate of genetic gain but will have a large impact on the structure of breeding programmes.
Thomson, R L; Buckley, J D; Moran, L J; Noakes, M; Clifton, P M; Norman, R J; Brinkworth, G D
2009-08-01
Anti-Müllerian hormone (AMH) has been proposed as a clinical predictor of improvements in reproductive function following weight loss in overweight and obese women with polycystic ovary syndrome (PCOS). This study aimed to assess whether baseline and/or change in AMH levels with weight loss predict improvements in reproductive function in overweight and obese women with PCOS. Fifty-two overweight and obese women with PCOS and reproductive impairment (age 29.8 +/- 0.8 years, BMI 36.5 +/- 0.7 kg/m(2)) followed a 20-week weight loss programme. AMH, weight, menstrual cyclicity and ovulatory function were assessed at baseline and post-intervention. Participants who responded with improvements in reproductive function (n = 26) had lower baseline AMH levels (23.5 +/- 3.7 versus 32.5 +/- 2.9 pmol/l; P = 0.03) and experienced greater weight loss (-11.7 +/- 1.2 versus -6.4 +/- 0.9 kg; P = 0.001) compared with those who did not respond (n = 26). Logistic regression analysis showed that weight loss and baseline AMH were independently related to improvements in reproductive function (P = 0.002 and P = 0.013, respectively). AMH levels did not change with weight loss in both responders and non-responders. In overweight and obese women with PCOS and reproductive dysfunction, a 20-week weight loss intervention resulted in improvements in reproductive function but no change in AMH levels. ACTRN12606000198527.
Fetal programming of sexual development and reproductive function.
Zambrano, Elena; Guzmán, Carolina; Rodríguez-González, Guadalupe L; Durand-Carbajal, Marta; Nathanielsz, Peter W
2014-01-25
The recent growth of interest in developmental programming of physiological systems has generally focused on the cardiovascular system (especially hypertension) and predisposition to metabolic dysfunction (mainly obesity and diabetes). However, it is now clear that the full range of altered offspring phenotypes includes impaired reproductive function. In rats, sheep and nonhuman primates, reproductive capacity is altered by challenges experienced during critical periods of development. This review will examine available experimental evidence across commonly studied experimental species for developmental programming of female and male reproductive function throughout an individual's life-course. It is necessary to consider events that occur during fetal development, early neonatal life and prior to and during puberty, during active reproductive life and aging as reproductive performance declines. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.
Lysophosphatidic Acid (LPA) Signaling in Human and Ruminant Reproductive Tract
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
Budak, Erdal; Fernández Sánchez, Manuel; Bellver, José; Cerveró, Ana; Simón, Carlos; Pellicer, Antonio
2006-06-01
To summarize the effects of novel hormones (leptin, ghrelin, adiponectin, resistin, and PYY3-36) secreted from adipose tissue and the gastrointestinal tract that have been discovered to exert different effects on several reproductive functions, such as the hypothalamic-pituitary-gonadal axis, embryo development, implantation physiology, and clinically relevant conditions. A MEDLINE computer search was performed to identify relevant articles. Leptin and ghrelin exert important roles on body weight regulation, eating behavior, and reproduction, acting on the central nervous system and target reproductive organs. As a marker of adequate nutritional stores, these hormones may act on the central nervous system to initiate the complex process of puberty and maintain normal reproductive function. In addition, leptin and ghrelin and their receptors are involved in reproductive events such as gonadal function, embryo development, and embryo-endometrial interaction. Leptin and ghrelin and other adipose tissue-secreted hormones have significant effects on reproduction. Acting through the brain, these hormones may serve as links between adipose tissue and the reproductive system to supply and regulate energy needs for normal reproduction and pregnancy. Future studies are needed to further clarify the role of these hormones in reproductive events and other related gynecological conditions.
Cardoso, A M; Alves, M G; Mathur, P P; Oliveira, P F; Cavaco, J E; Rato, L
2017-01-01
In the last decades, several studies evidenced a decrease in male fertility in developed countries. Although the aetiology of this trend in male reproductive health remains a matter of debate, environmental compounds that predispose to weight gain, namely obesogens, are appointed as contributors because of their action as endocrine disruptors. Obesogens favour adipogenesis by an imbalance of metabolic processes and can be found virtually everywhere. These compounds easily accumulate in tissues with high lipid content. Obesogens change the functioning of male reproductive axis, and, consequently, the testicular physiology and metabolism that are pivotal for spermatogenesis. The disruption of these tightly regulated metabolic pathways leads to adverse reproductive outcomes. Notably, adverse effects of obesogens may also promote disturbances in the metabolic performance of the following generations, through epigenetic modifications passed by male gametes. Thus, unveiling the molecular pathways by which obesogens induce toxicity that may end up in epigenetic modifications is imperative. Otherwise, a transgenerational susceptibility to metabolic diseases may be favoured. We present an up-to-date overview of the impact of obesogens on testicular physiology, with a particular focus on testicular metabolism. We also address the effects of obesogens on male reproductive parameters and the subsequent consequences for male fertility. © 2016 World Obesity Federation.
CRITICAL WINDOWS FOR REPRODUCTIVE HEALTH IN CHILDREN AND ADOLESCENTS
This workgroup report addresses the central question: what are the critical windows during development (pre-conception through puberty) when exposure to xenobiotics may have the greatest adverse impact on subsequent reproductive health. The reproductive system develops in stages...
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.
Mayhew, Susannah H; Ploubidis, George B; Sloggett, Andy; Church, Kathryn; Obure, Carol D; Birdthistle, Isolde; Sweeney, Sedona; Warren, Charlotte E; Watts, Charlotte; Vassall, Anna
2016-01-01
The body of knowledge on evaluating complex interventions for integrated healthcare lacks both common definitions of 'integrated service delivery' and standard measures of impact. Using multiple data sources in combination with statistical modelling the aim of this study is to develop a measure of HIV-reproductive health (HIV-RH) service integration that can be used to assess the degree of service integration, and the degree to which integration may have health benefits to clients, or reduce service costs. Data were drawn from the Integra Initiative's client flow (8,263 clients in Swaziland and 25,539 in Kenya) and costing tools implemented between 2008-2012 in 40 clinics providing RH services in Kenya and Swaziland. We used latent variable measurement models to derive dimensions of HIV-RH integration using these data, which quantified the extent and type of integration between HIV and RH services in Kenya and Swaziland. The modelling produced two clear and uncorrelated dimensions of integration at facility level leading to the development of two sub-indexes: a Structural Integration Index (integrated physical and human resource infrastructure) and a Functional Integration Index (integrated delivery of services to clients). The findings highlight the importance of multi-dimensional assessments of integration, suggesting that structural integration is not sufficient to achieve the integrated delivery of care to clients--i.e. "functional integration". These Indexes are an important methodological contribution for evaluating complex multi-service interventions. They help address the need to broaden traditional evaluations of integrated HIV-RH care through the incorporation of a functional integration measure, to avoid misleading conclusions on its 'impact' on health outcomes. This is particularly important for decision-makers seeking to promote integration in resource constrained environments.
Effects of Environmental Toxicants on the Neuroendocrine Control of Female Reproduction
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...
CH 21: Toxic Responses of the Reproductive System
Any evaluation of toxicity to reproduction will have as an important consideration that events may not only be on the adults having impact on their likelihood to have children, but also impact the viability and quality of life of their potential offspring and feasibly even affect...
French, J.B.; Henry, P.F.P.; Rattner, B.A.; Ottinger, M.A.
1998-01-01
Diverse field and experimental studies suggest that abnormal sexual and reproductive development in wildlife could be caused by endocrine-like action of pollutants on embryos, and that functional deficits would be evident only later in life, during breeding. We tested these hypotheses in American kestrels (Falco sparverius). Aroclor 1242 is a commercial mixture of PCB congeners shown to be estrogenic in mice and the mixture approximates the environmental exposure of Common terns (Sterna hirundo) where abnormal development of gonads in male tern chicks was seen. Pairs of kestrels were exposed to high and low levels of Aroclor in food resulting in mean egg concentrations of 80.4 and 9.4 ppm respectively. The gonadal orphology of hatchlings was consistent with their genetic sex, and male testes showed only little histological intersexuality; fledglings had nomal gonadal morphology and histology. Female hatchlings tended to show increased androgen and decreased estrogen in their serum with increased dose of Aroclor. Similarly exposed siblings were raised to breeding age and displayed some differences in incubation behavior, but no difference in reproductive output from controls. Overall, kestrels exposed to Aroclor 1242 as embryos showed some moderate disruption of normal development, but siblings showed little functional deficit at breeding age.
Płotek, Włodzimierz; Łyskawa, Wojciech; Kluzik, Anna; Grześkowiak, Małgorzata; Podlewski, Roland; Żaba, Zbigniew; Drobnik, Leon
2014-02-03
Human cognitive functioning can be assessed using different methods of testing. Age, level of education, and gender may influence the results of cognitive tests. The well-known Trail Making Test (TMT), which is often used to measure the frontal lobe function, and the experimental test of Interval Timing (IT) were compared. The methods used in IT included reproduction of auditory and visual stimuli, with the subsequent production of the time intervals of 1-, 2-, 5-, and 7-seconds durations with no pattern. Subjects included 64 healthy adult volunteers aged 18-63 (33 women, 31 men). Comparisons were made based on age, education, and gender. TMT was performed quickly and was influenced by age, education, and gender. All reproduced visual and produced intervals were shortened and the reproduction of auditory stimuli was more complex. Age, education, and gender have more pronounced impact on the cognitive test than on the interval timing test. The reproduction of the short auditory stimuli was more accurate in comparison to other modalities used in the IT test. The interval timing, when compared to the TMT, offers an interesting possibility of testing. Further studies are necessary to confirm the initial observation.
Gulf Coast oil disaster: impact on human reproduction.
Merhi, Zaher O
2010-10-01
The catastrophic British Petroleum oil spill in the Gulf of Mexico has reached the shores of the United States, along with unpredictable effects on the health of local communities. The potential impact of the disaster on female and male reproduction will be discussed in this report, to provide greater clinician awareness about the potential consequences of this calamity and to call for more research on this subject. Copyright © 2010 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.
Mondet, Fanny; Rau, Andrea; Klopp, Christophe; Rohmer, Marine; Severac, Dany; Le Conte, Yves; Alaux, Cedric
2018-05-04
The parasite Varroa destructor represents a significant threat to honeybee colonies. Indeed, development of Varroa infestation within colonies, if left untreated, often leads to the death of the colony. Although its impact on bees has been extensively studied, less is known about its biology and the functional processes governing its adult life cycle and adaptation to its host. We therefore developed a full life cycle transcriptomic catalogue in adult Varroa females and included pairwise comparisons with males, artificially-reared and non-reproducing females (10 life cycle stages and conditions in total). Extensive remodeling of the Varroa transcriptome was observed, with an upregulation of energetic and chitin metabolic processes during the initial and final phases of the life cycle (e.g. phoretic and post-oviposition stages), whereas during reproductive stages in brood cells genes showing functions related to transcriptional regulation were overexpressed. Several neurotransmitter and neuropeptide receptors involved in behavioural regulation, as well as active compounds of salivary glands, were also expressed at a higher level outside the reproductive stages. No difference was detected between artificially-reared phoretic females and their counterparts in colonies, or between females who failed to reproduce and females who successfully reproduced, indicating that phoretic individuals can be reared outside host colonies without impacting their physiology and that mechanisms underlying reproductive failure occur before oogenesis. We discuss how these new findings reveal the remarkable adaptation of Varroa to its host biology and notably to the switch from living on adults to reproducing in sealed brood cells. By spanning the entire adult life cycle, our work captures the dynamic changes in the parasite gene expression and serves as a unique resource for deciphering Varroa biology and identifying new targets for mite control.
Wahab, F; Shahab, M; Behr, R
2015-05-01
Recently, kisspeptin (KP) and gonadotropin inhibitory hormone (GnIH), two counteracting neuropeptides, have been acknowledged as significant regulators of reproductive function. KP stimulates reproduction while GnIH inhibits it. These two neuropeptides seem to be pivotal for the modulation of reproductive activity in response to internal and external cues. It is well-documented that the current metabolic status of the body is closely linked to its reproductive output. However, how reproductive function is regulated by the body's energy status is less clear. Recent studies have suggested an active participation of hypothalamic KP and GnIH in the modulation of reproductive function according to available metabolic cues. Expression of KISS1, the KP encoding gene, is decreased while expression of RFRP (NPVF), the gene encoding GnIH, is increased in metabolic deficiency conditions. The lower levels of KP, as suggested by a decrease in KISS1 gene mRNA expression, during metabolic deficiency can be corrected by administration of exogenous KP, which leads to an increase in reproductive hormone levels. Likewise, administration of RF9, a GnIH receptor antagonist, can reverse the inhibitory effect of fasting on testosterone in monkeys. Together, it is likely that the integrated function of both these hypothalamic neuropeptides works as a reproductive output regulator in response to a change in metabolic status. In this review, we have summarized literature from nonprimate and primate studies that demonstrate the involvement of KP and GnIH in the metabolic regulation of reproduction. © 2015 The authors.
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 variability among populations for differences in the threshold size for first reproduction between male and female sexual functions in a tree species. The relatively uniform size at which individuals begin reproducing through their male function probably represents the fact that pollen dispersal is also relatively invariant among sites. However, the genetic variability in the timing of female reproduction probably reflects environment-dependent costs of cone production. The results also suggest that early sex allocation in this species might evolve under constraints that do not apply to other conifers.
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 study represents the first report of genetic variability among populations for differences in the threshold size for first reproduction between male and female sexual functions in a tree species. The relatively uniform size at which individuals begin reproducing through their male function probably represents the fact that pollen dispersal is also relatively invariant among sites. However, the genetic variability in the timing of female reproduction probably reflects environment-dependent costs of cone production. The results also suggest that early sex allocation in this species might evolve under constraints that do not apply to other conifers. PMID:23002272
Over the past decade, our research team at the US EPA Mid-Continent Ecology Division has employed systems biology approaches to examine and understand impacts of environmental contaminants on fish reproduction. Our systems biology approach is one in which iterations of model cons...
Orff, Henry J.; Meliska, Charles J.; Lopez, Ana; Martinez, Fernando; Sorenson, Diane; Parry, Barbara L.
2012-01-01
This archival cross-sectional investigation examined the impact of mood, reproductive status (RS), and age on polysomnographic (PSG) measures in women. PSG was performed on 73 normal controls (NC) and 64 depressed patients (DP), in the course of studies in menstruating, pregnant, postpartum, and peri- and postmenopausal women. A two-factor, between-subjects multivariate analysis of variance (MANOVA) was used to test the main effects of reproductive status (RS: menstrual vs pregnant vs postpartum vs menopausal) and diagnosis (NC vs DP), and their interaction, on PSG measures. To further refine the analyses, a two-factor, between subjects MANOVA was used to test the main effects of age (19 to 27 vs 28 to 36 vs 37 to 45 vs 46+ years) and diagnosis on the PSG data. Analyses revealed that in DP women, rapid eye movement (REM) sleep percentage was significantly elevated relative to NC across both RS and age. Significant differences in sleep efficiency, Stage 1%, and REM density were associated with RS; differences in total sleep time, Stage 2 percentage, and Stage 4 percentage were associated with differences in age. Both RS and age were related to differences in sleep latency, Stage 3 percentage, and Delta percentage. Finally, wake after sleep onset time, REM percentage, and REM latency did not vary with respect to RS or age. Overall, this investigation examined three major variables (mood, RS, and age) that are known to impact sleep in women. Of the variables, age appeared to have the greatest impact on PSG sleep measures, reflecting changes occurring across the lifespan. PMID:23393417
Beadex Function in the Motor Neurons Is Essential for Female Reproduction in Drosophila melanogaster
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
Lauxmann, Martin A; Annunziata, Maria G; Brunoud, Géraldine; Wahl, Vanessa; Koczut, Andrzej; Burgos, Asdrubal; Olas, Justyna J; Maximova, Eugenia; Abel, Christin; Schlereth, Armin; Soja, Aleksandra M; Bläsing, Oliver E; Lunn, John E; Vernoux, Teva; Stitt, Mark
2016-04-01
The impact of transient carbon depletion on reproductive growth in Arabidopsis was investigated by transferring long-photoperiod-grown plants to continuous darkness and returning them to a light-dark cycle. After 2 days of darkness, carbon reserves were depleted in reproductive sinks, and RNA in situ hybridization of marker transcripts showed that carbon starvation responses had been initiated in the meristem, anthers and ovules. Dark treatments of 2 or more days resulted in a bare-segment phenotype on the floral stem, with 23-27 aborted siliques. These resulted from impaired growth of immature siliques and abortion of mature and immature flowers. Depolarization of PIN1 protein and increased DII-VENUS expression pointed to rapid collapse of auxin gradients in the meristem and inhibition of primordia initiation. After transfer back to a light-dark cycle, flowers appeared and formed viable siliques and seeds. A similar phenotype was seen after transfer to sub-compensation point irradiance or CO2 . It also appeared in a milder form after a moderate decrease in irradiance and developed spontaneously in short photoperiods. We conclude that Arabidopsis inhibits primordia initiation and aborts flowers and very young siliques in C-limited conditions. This curtails demand, safeguarding meristem function and allowing renewal of reproductive growth when carbon becomes available again. © 2015 John Wiley & Sons Ltd.
NASA Astrophysics Data System (ADS)
Lynch, Sharon A.; Darmody, Grainne; O'Dwyer, Katie; Gallagher, Mary Catherine; Nolan, Sinead; McAllen, Rob; Culloty, Sarah C.
2016-11-01
The European sea squirt Ascidiella aspersa is a solitary tunicate native to the northeastern Atlantic, commonly found in shallow and sheltered marine ecosystems where it is capable of forming large clumps and outcompeting other invertebrate fauna at settlement. To date, there have been relatively few studies looking at the reproductive biology and health status of this invasive species. Between 2006 and 2010 sampling of a native population took place to investigate gametogenesis and reproductive cycle and to determine the impact of settlement depth on reproduction. In addition, parasite diversity and impact was assessed. A staging system to assess reproductive development was determined. The study highlighted that from year to year the tunicate could change its reproductive strategy from single sex to hermaphrodite, with spawning possible throughout the year. Depth did not impact on sex determination, however, gonad maturation and spawning occurred earlier in individuals in deeper waters compared to shallow depth and it also occurred later in A. aspersa at sites further away from the open sea. Four significant parasite groups including eugregarines, ciliates, trematodes and turbellarians were detected and prevalence of parasite infections increased in A. aspersa at sites with a reduced water flow rate. This study demonstrates the high biotic potential of this ascidian bioinvader to have a negative impact on native fauna in an introduced ecosystem, due to its highly efficient reproductive and resource allocation strategies. Artificial structures such as mooring lines can harbour large aggregations of A. aspersa, however, these manmade habitats may facilitate the colonisation and establishment of this invasive species in the benthos. Additionally, the parasite communities that A. aspersa harbour may also exacerbate its negative impact, both ecologically and economically, in an introduced area by possibly leading to the emergence of new disease in native species i.e. pathogen spillover.
Biological invasions as disruptors of plant reproductive mutualisms.
Traveset, Anna; Richardson, David M
2006-04-01
Invasive alien species affect the composition and functioning of invaded ecosystems in many ways, altering ecological interactions that have arisen over evolutionary timescales. Specifically, disruptions to pollination and seed-dispersal mutualistic interactions are often documented, although the profound implications of such impacts are not widely recognized. Such disruptions can occur via the introduction of alien pollinators, seed dispersers, herbivores, predators or plants, and we define here the many potential outcomes of each situation. The frequency and circumstances under which each category of mechanisms operates are also poorly known. Most evidence is from population-level studies, and the implications for global biodiversity are difficult to predict. Further insights are needed on the degree of resilience in interaction networks, but the preliminary picture suggests that invasive species frequently cause profound disruptions to plant reproductive mutualisms.
Sleep deprivation suppresses aggression in Drosophila
Kayser, Matthew S; Mainwaring, Benjamin; Yue, Zhifeng; Sehgal, Amita
2015-01-01
Sleep disturbances negatively impact numerous functions and have been linked to aggression and violence. However, a clear effect of sleep deprivation on aggressive behaviors remains unclear. We find that acute sleep deprivation profoundly suppresses aggressive behaviors in the fruit fly, while other social behaviors are unaffected. This suppression is recovered following post-deprivation sleep rebound, and occurs regardless of the approach to achieve sleep loss. Genetic and pharmacologic approaches suggest octopamine signaling transmits changes in aggression upon sleep deprivation, and reduced aggression places sleep-deprived flies at a competitive disadvantage for obtaining a reproductive partner. These findings demonstrate an interaction between two phylogenetically conserved behaviors, and suggest that previous sleep experiences strongly modulate aggression with consequences for reproductive fitness. DOI: http://dx.doi.org/10.7554/eLife.07643.001 PMID:26216041
Hormonal regulation of longevity in mammals
Brown-Borg, Holly M.
2007-01-01
Multiple biological and environmental factors impact the life span of an organism. The endocrine system is a highly integrated physiological system in mammals that regulates metabolism, growth, reproduction, and response to stress, among other functions. As such, this pervasive entity has a major influence on aging and longevity. The growth hormone, insulin-like growth factor-1 and insulin pathways have been at the forefront of hormonal control of aging research in the last few years. Other hormones, including those from the thyroid and reproductive system have also been studied in terms of life span regulation. The relevance of these hormones to human longevity remains to be established, however the evidence from other species including yeast, nematodes, and flies suggest that evolutionarily well-conserved mechanisms are at play and the endocrine system is a key determinant. PMID:17360245
Vijver, Martina G; Bolte, John F B; Evans, Tracy R; Tamis, Wil L M; Peijnenburg, Willie J G M; Musters, C J M; de Snoo, Geert R
2014-01-01
Organisms are exposed to electromagnetic fields from the introduction of wireless networks that send information all over the world. In this study we examined the impact of exposure to the fields from mobile phone base stations (GSM 900 MHz) on the reproductive capacity of small, virgin, invertebrates. A field experiment was performed exposing four different invertebrate species at different distances from a radiofrequency electromagnetic fields (RF EMF) transmitter for a 48-h period. The control groups were isolated from EMF exposure by use of Faraday cages. The response variables as measured in the laboratory were fecundity and number of offspring. Results showed that distance was not an adequate proxy to explain dose-response regressions. No significant impact of the exposure matrices, measures of central tendency and temporal variability of EMF, on reproductive endpoints was found. Finding no impact on reproductive capacity does not fully exclude the existence of EMF impact, since mechanistically models hypothesizing non-thermal-induced biological effects from RF exposure are still to be developed. The exposure to RF EMF is ubiquitous and is still increasing rapidly over large areas. We plea for more attention toward the possible impacts of EMF on biodiversity.
Pandey, Ajai K; Gupta, Anumegha; Tiwari, Meenakshi; Prasad, Shilpa; Pandey, Ashutosh N; Yadav, Pramod K; Sharma, Alka; Sahu, Kankshi; Asrafuzzaman, Syed; Vengayil, Doyil T; Shrivastav, Tulsidas G; Chaube, Shail K
2018-07-01
Stress is deeply rooted in the society and women are frequently exposed to psychological, physical and physiological stressors. Psychological stress disturbs reproductive health by inducing generation of reactive oxygen species (ROS) and thereby oxidative stress (OS). The increased OS may affect physiology of ovary, oocyte quality and cause female reproductive health disorders. To overcome stress-mediated reproductive health disorders in women, shatavari (Asparagus racemosus) is frequently recommended in Ayurvedic system of medicine. Although shatavari is one of the major health tonics and most popular rasayana drugs to treat reproductive ailments of women, underlying mechanism of shatavari action at the level of ovary remains poorly understood. Based on the existing studies, we propose that shatavari may improve female reproductive health complications including hormonal imbalance, polycystic ovarian syndrome (PCOS), follicular growth and development, oocyte quality and infertility possibly by reducing OS level and increasing antioxidants level in the body. Further studies are required to elucidate the mechanism of shatavari actions at the level of ovary and oocyte that directly impacts the reproductive health of women. Copyright © 2018 Elsevier Masson SAS. All rights reserved.
The reach and impact of social marketing and reproductive health communication campaigns in Zambia.
Van Rossem, Ronan; Meekers, Dominique
2007-12-18
Like many sub-Saharan African countries, Zambia is dealing with major health issues, including HIV/AIDS, family planning, and reproductive health. To address reproductive health problems and the HIV/AIDS epidemic in Zambia, several social marketing and health communication programs focusing on reproductive and HIV/AIDS prevention programs are being implemented. This paper describes the reach of these programs and assesses their impact on condom use. This paper assesses the reach of selected radio and television programs about family planning and HIV/AIDS and of communications about the socially marketed Maximum condoms in Zambia, as well as their impact on condom use, using data from the 2001-2002 Zambia Demographic and Health Survey. To control for self-selection and endogeneity, we use a two-stage regression model to estimate the effect of program exposure on the behavioural outcomes. Those who were exposed to radio and television programs about family planning and HIV/AIDS were more likely to have ever used a condom (OR = 1.16 for men and 1.06 for women). Men highly exposed to Maximum condoms social marketing communication were more likely than those with low exposure to the program to have ever used a condom (OR = 1.48), and to have used a condom at their last sexual intercourse (OR = 1.23). Findings suggest that the reproductive health and social marketing campaigns in Zambia reached a large portion of the population and had a significant impact on condom use. The results suggest that future reproductive health communication campaigns that invest in radio programming may be more effective than those investing in television programming, and that future campaigns should seek to increase their impact among women, perhaps by focusing on the specific constrains that prevent females from using condoms.
Role of leptin in female reproduction.
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.
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...
Naufahu, Jane; Cunliffe, Adam D; Murray, Joanne F
2013-01-01
Melanin-concentrating hormone (MCH) is an anabolic neuropeptide with multiple and diverse physiological functions including a key role in energy homoeostasis. Rodent studies have shown that the ablation of functional MCH results in a lean phenotype, increased energy expenditure and resistance to diet-induced obesity. These findings have generated interest among pharmaceutical companies vigilant for potential anti-obesity agents. Nutritional status affects reproductive physiology and behaviours, thereby optimising reproductive success and the ability to meet energetic demands. This complex control system entails the integration of direct or indirect peripheral stimuli with central effector systems and involves numerous mediators. A role for MCH in the reproductive axis has emerged, giving rise to the premise that MCH may serve as an integratory mediator between those discrete systems that regulate energy balance and reproductive function. Hence, this review focuses on published evidence concerning i) the role of MCH in energy homoeostasis and ii) the regulatory role of MCH in the reproductive axis. The question as to whether the MCH system mediates the integration of energy homoeostasis with the neuroendocrine reproductive axis and, if so, by what means has received limited coverage in the literature; evidence to date and current theories are summarised herein.
Scully, C M; Estill, C T; Amodei, R; McKune, A; Gribbin, K P; Meaker, M; Stormshak, F; Roselli, C E
2018-01-01
Prenatal androgens are largely responsible for growth and differentiation of the genital tract and testis and for organization of the control mechanisms regulating male reproductive physiology and behavior. The aim of the present study was to evaluate the impact of inappropriate exposure to excess testosterone (T) during the first trimester of fetal development on the reproductive function, sexual behavior, and fertility potential of rams. We found that biweekly maternal T propionate (100 mg) treatment administered from Day 30-58 of gestation significantly decreased (P < 0.05) postpubertal scrotal circumference and sperm concentration. Prenatal T exposure did not alter ejaculate volume, sperm motility and morphology or testis morphology. There was, however, a trend for more T-exposed rams than controls to be classified as unsatisfactory potential breeders during breeding soundness examinations. Postnatal serum T concentrations were not affected by prenatal T exposure, nor was the expression of key testicular genes essential for spermatogenesis and steroidogenesis. Basal serum LH did not differ between treatment groups, nor did pituitary responsiveness to GnRH. T-exposed rams, like control males, exhibited vigorous libido and were sexually attracted to estrous females. In summary, these results suggest that exposure to exogenous T during the first trimester of gestation can negatively impact spermatogenesis and compromise the reproductive fitness of rams. Copyright © 2017 Elsevier Inc. All rights reserved.
Fitness impacts of tapeworm parasitism on wild gelada monkeys at Guassa, Ethiopia.
Nguyen, Nga; Fashing, Peter J; Boyd, Derek A; Barry, Tyler S; Burke, Ryan J; Goodale, C Barret; Jones, Sorrel C Z; Kerby, Jeffrey T; Kellogg, Bryce S; Lee, Laura M; Miller, Carrie M; Nurmi, Niina O; Ramsay, Malcolm S; Reynolds, Jason D; Stewart, Kathrine M; Turner, Taylor J; Venkataraman, Vivek V; Knauf, Yvonne; Roos, Christian; Knauf, Sascha
2015-05-01
Parasitism is expected to impact host morbidity or mortality, although the fitness costs of parasitism have rarely been quantified for wildlife hosts. Tapeworms in the genus Taenia exploit a variety of vertebrates, including livestock, humans, and geladas (Theropithecus gelada), monkeys endemic to the alpine grasslands of Ethiopia. Despite Taenia's adverse societal and economic impacts, we know little about the prevalence of disease associated with Taenia infection in wildlife or the impacts of this disease on host health, mortality and reproduction. We monitored geladas at Guassa, Ethiopia over a continuous 6½ year period for external evidence (cysts or coenuri) of Taenia-associated disease (coenurosis) and evaluated the impact of coenurosis on host survival and reproduction. We also identified (through genetic and histological analyses) the tapeworms causing coenurosis in wild geladas at Guassa as Taenia serialis. Nearly 1/3 of adult geladas at Guassa possessed ≥1 coenurus at some point in the study. Coenurosis adversely impacted gelada survival and reproduction at Guassa and this impact spanned two generations: adults with coenuri suffered higher mortality than members of their sex without coenuri and offspring of females with coenuri also suffered higher mortality. Coenurosis also negatively affected adult reproduction, lengthening interbirth intervals and reducing the likelihood that males successfully assumed reproductive control over units of females. Our study provides the first empirical evidence that coenurosis increases mortality and reduces fertility in wild nonhuman primate hosts. Our research highlights the value of longitudinal monitoring of individually recognized animals in natural populations for advancing knowledge of parasite-host evolutionary dynamics and offering clues to the etiology and control of infectious disease. © 2015 Wiley Periodicals, Inc.
Gavin, Loretta E; Williams, Jessica R; Rivera, Maria I; Lachance, Christina R
2015-08-01
When caring for an adolescent client, providers of contraceptive services must consider whether and how to encourage parent/guardian-child communication about the adolescent's reproductive health. The objective of this systematic review was to summarize the evidence on the effectiveness of programs designed to increase parent-child communication about reproductive health. The review was used to inform national recommendations on quality family planning services. Data analysis occurred from mid-2011 through 2012. Several electronic bibliographic databases were used to identify relevant articles, including PubMed, CINAHL, PsycINFO, and Popline, published from January 1985 through February 2011. Sixteen articles met the inclusion criteria: all studies examined the impact on at least one medium- or short-term outcome, and two studies assessed the impact on teen pregnancy. One study examined the impact of a program conducted in a clinic setting; the remainder examined the impact of programs in community settings. All studies showed a positive impact on at least one short-term outcome, and 12 of 16 studies showed an increase in parent-child communication about reproductive health. Four of seven studies found an impact on sexual risk behavior. Most programs increased parent-child communication, and several resulted in reduced sexual risk behavior of adolescents. This suggests that delivering a clinic-based program that effectively helps parents/guardians talk to their adolescent child(ren) about reproductive health, or referring parents/guardians to an evidence-based program in the community, may be beneficial. However, further rigorous research on delivery of these programs in clinical settings is needed. Published by Elsevier Inc.
The Impact of Reproductive Technologies on Stallion Mitochondrial Function.
Peña, F J; Plaza Davila, M; Ball, B A; Squires, E L; Martin Muñoz, P; Ortega Ferrusola, C; Balao da Silva, C
2015-08-01
The traditional assessment of stallion sperm comprises evaluation of sperm motility and membrane integrity and identification of abnormal morphology of the spermatozoa. More recently, the progressive introduction of flow cytometry is increasing the number of tests available. However, compared with other sperm structures and functions, the evaluation of mitochondria has received less attention in stallion andrology. Recent research indicates that sperm mitochondria are key structures in sperm function suffering major changes during biotechnological procedures such as cryopreservation. In this paper, mitochondrial structure and function will be reviewed in the stallion, when possible specific stallion studies will be discussed, and general findings on mammalian mitochondrial function will be argued when relevant. Especial emphasis will be put on their role as source of reactive oxygen species and in their role regulating sperm lifespan, a possible target to investigate with the aim to improve the quality of frozen-thawed stallion sperm. Later on, the impact of current sperm technologies, principally cryopreservation, on mitochondrial function will be discussed pointing out novel areas of research interest with high potential to improve current sperm technologies. © 2015 Blackwell Verlag GmbH.
The ecology and evolutionary endocrinology of reproduction in the human female.
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 norm rather than an aberration. Other than woman's age, the determinants of these differences are not well characterized, although developmental conditions, dietary practices, genetic variation, and epigenetic mechanisms have all been hypothesized to play some role. It is also evident that the reproductive functioning of women born and living in arduous conditions is not analogous to that of athletes, dieters, or even the lower end of the "normal range" of HPO functioning in wealthier populations. Contrary to the presumption that humans have low fecundity and an inefficient reproductive system, both theory and present evidence suggest that we may actually have very high fecundity and a reproductive system that has evolved to be flexible, ruthlessly efficient and, most importantly, strategic. Copyright 2009 Wiley-Liss, Inc.
Sleep Apnea, Reproductive Hormones and Quality of Sexual Life in Severely Obese Men
Hammoud, Ahmad O.; Walker, James M.; Gibson, Mark; Cloward, Tom V.; Hunt, Steven C.; Kolotkin, Ronette L.; Adams, Ted D.; Meikle, A. Wayne
2013-01-01
The effect of sleep apnea on the reproductive function of obese men is not entirely elucidated. The objective of this study was to define the effect of sleep apnea on the reproductive hormones and sexual function in obese men. This study included 89 severely obese men with BMI ≥35 kg/m2 considering gastric bypass surgery. Anthropometrics (weight, and BMI), reproductive hormones, and sleep studies were measured. The sexual quality of life was assessed using the Impact of Weight on Quality of Life-Lite questionnaire (IWQOL-Lite). The mean age of our patients was 46.9 ± 11.0 years, the mean BMI was 47.8 ± 8.7 kg/m2 and the mean weight was 337.7 ± 62.4 lb. After correction for age and BMI, means of free testosterone per severity group of sleep apnea were as follows: no or mild sleep apnea 74.4 ± 3.8 pg/ml, moderate sleep apnea 68.6 ± 4.2 pg/ml, and severe sleep apnea 60.2 ± 2.92 pg/ml, P = 0.014. All other parameters of sleep apnea including hypopnea index, percent time below a SpO2 of 90%, and percent time below a SpO2 of 80% were also negatively correlated with testosterone levels after correction for age and BMI. BMI and presence of coronary artery disease decreased the sexual quality of life. Sleep apnea was associated with reduced sexual quality of life. In summary, sleep apnea negatively affects testosterone levels independent of BMI. Severely obese men had decreased sexual quality of life. PMID:21273994
Jak2 is Necessary for Neuroendocrine Control of Female Reproduction
Wu, Sheng; Divall, Sara; Hoffman, Gloria E.; Le, Wei Wei; Wagner, Kay-Uwe; Wolfe, Andrew
2011-01-01
GnRH neurons represent the final common output of signals from the brain that regulates reproductive function. A wide range of environmental factors impact GnRH neuron activity including disease, stress, nutrition, and seasonal cues, as well as gonadal steroid hormones. The CNS response is thought to be mediated, at least in part, through intermediate signaling molecules that affect GnRH neuronal activity. In vitro, GnRH neuronal cell lines respond to a variety of ligands which activate the Jak/STAT intracellular signaling pathway. In order to determine its biological function in reproduction, we used Cre/LoxP technology to generate GnRH neuron specific Jak2 conditional knockout (Jak2 G−/−) mice. GnRH mRNA levels were reduced in Jak2 G−/− mice when compared to controls, while the number of GnRH neurons was equivalent, indicating a reduction in GnRH gene expression. Secretion of GnRH is also reduced as basal serum LH levels were significantly lower in female Jak2 G−/− mice while the pituitary responded normally to exogenous GnRH. Preovulatory LH surge levels were blunted in Jak2 G−/− mice, which was correlated with reduced GnRH neuronal activation as assessed by c-Fos. However the activation of GnRH neurons following release from estrogen negative feedback is retained. Female Jak2 G−/− mice exhibited significantly delayed puberty and first estrus, abnormal estrous cyclicity and impaired fertility. These results demonstrate an essential role for Jak2 signaling in GnRH neurons for normal reproductive development and fertility in female mice. PMID:21209203
The eastern snapping turtle (Chelydra serpentina) is widely distributed throughout the eastern and central U.S. and may be a useful model organism to study land use impacts on water quality. We compared the reproductive condition of C. serpentina from a pond impacted by runoff fr...
Neural mechanisms of reproduction in females as a predisposing factor for drug addiction.
Hedges, Valerie L; Staffend, Nancy A; Meisel, Robert L
2010-04-01
There is an increasing awareness that adolescent females differ from males in their response to drugs of abuse and consequently in their vulnerability to addiction. One possible component of this vulnerability to drug addiction is the neurobiological impact that reproductive physiology and behaviors have on the mesolimbic dopamine system, a key neural pathway mediating drug addiction. In this review, we examine animal models that address the impact of ovarian cyclicity, sexual affiliation, sexual behavior, and maternal care on the long-term plasticity of the mesolimbic dopamine system. The thesis is that this plasticity in synaptic neurotransmission stemming from an individual's normal life history contributes to the pathological impact of drugs of abuse on the neurobiology of this system. Hormones released during reproductive cycles have only transient effects on these dopamine systems, whereas reproductive behaviors produce a persistent sensitization of dopamine release and post-synaptic neuronal responsiveness. Puberty itself may not represent a neurobiological risk factor for drug abuse, but attendant behavioral experiences may have a negative impact on females engaging in drug use.
Neural Mechanisms of Reproduction in Females as a Predisposing Factor for Drug Addiction
Hedges, Valerie L.; Staffend, Nancy A.; Meisel, Robert L.
2010-01-01
There is an increasing awareness that adolescent females differ from males in their response to drugs of abuse and consequently in their vulnerability to addiction. One possible component of this vulnerability to drug addiction is the neurobiological impact that reproductive physiology and behaviors have on the mesolimbic dopamine system, a key neural pathway mediating drug addiction. In this review, we examine animal models that address the impact of ovarian cyclicity, sexual affiliation, sexual behavior, and maternal care on the long-term plasticity of the mesolimbic dopamine system. The thesis is that this plasticity in synaptic neurotransmission stemming from an individual’s normal life history contributes to the pathological impact of drugs of abuse on the neurobiology of this system. Hormones released during reproductive cycles have only transient effects on these dopamine systems, whereas reproductive behaviors produce a persistent sensitization of dopamine release and postsynaptic neuronal responsiveness. Puberty itself may not represent a neurobiological risk factor for drug abuse, but attendant behavioral experiences may have a negative impact on females engaging in drug use. PMID:20176045
Cuena-Lombraña, Alba; Fois, Mauro; Fenu, Giuseppe; Cogoni, Donatella; Bacchetta, Gianluigi
2018-03-30
Increases in temperature have been predicted and reported for the Mediterranean mountain ranges due to global warming and this phenomenon is expected to have profound consequences on biodiversity and ecosystem functioning. We hereby present the case of Gentiana lutea L. subsp. lutea, a rhizomatous long-lived plant living in Central-Southern Europe, which is at the edge of its ecological and distributional range in Sardinia. Concretely, we analysed the reproductive success experienced during three phenological cycles (2013/2014, 2014/2015 and 2015/2016) in four representative populations, with particular attention to the phenological cycle of 2014/2015, which has been recorded as one of the warmest periods of the last decades. The Smirnov-Grubbs test was used to evaluate differences in temperature and precipitation regimes among historical data and the analysed years, while the Kruskal-Wallis followed by the Wilcoxon test was used to measure differences between anthesis and reproductive performances among cycles and populations. In addition, generalised linear models were carried out to check relationships between climate variables and reproductive performance. Significant differences among climate variables and analysed cycles were highlighted, especially for maximum and mean temperatures. Such variations determined a non-flowering stage in two of the four analysed populations in 2014/2015 and significant differences of further five reproductive traits among cycles. These results confirmed that in current unstable climatic conditions, which are particularly evident in seasonal climates, reproductive success can be a sensitive and easily observable indicator of climatic anomalies. Considering the importance of this issue and the ease and cost-effectiveness of reproductive success monitoring, we argue that research in this sense can be a supporting tool for the enhancement of future crucial targets such as biodiversity conservation and the mitigation of global warming effects.
NASA Astrophysics Data System (ADS)
Cuena-Lombraña, Alba; Fois, Mauro; Fenu, Giuseppe; Cogoni, Donatella; Bacchetta, Gianluigi
2018-03-01
Increases in temperature have been predicted and reported for the Mediterranean mountain ranges due to global warming and this phenomenon is expected to have profound consequences on biodiversity and ecosystem functioning. We hereby present the case of Gentiana lutea L. subsp. lutea, a rhizomatous long-lived plant living in Central-Southern Europe, which is at the edge of its ecological and distributional range in Sardinia. Concretely, we analysed the reproductive success experienced during three phenological cycles (2013/2014, 2014/2015 and 2015/2016) in four representative populations, with particular attention to the phenological cycle of 2014/2015, which has been recorded as one of the warmest periods of the last decades. The Smirnov-Grubbs test was used to evaluate differences in temperature and precipitation regimes among historical data and the analysed years, while the Kruskal-Wallis followed by the Wilcoxon test was used to measure differences between anthesis and reproductive performances among cycles and populations. In addition, generalised linear models were carried out to check relationships between climate variables and reproductive performance. Significant differences among climate variables and analysed cycles were highlighted, especially for maximum and mean temperatures. Such variations determined a non-flowering stage in two of the four analysed populations in 2014/2015 and significant differences of further five reproductive traits among cycles. These results confirmed that in current unstable climatic conditions, which are particularly evident in seasonal climates, reproductive success can be a sensitive and easily observable indicator of climatic anomalies. Considering the importance of this issue and the ease and cost-effectiveness of reproductive success monitoring, we argue that research in this sense can be a supporting tool for the enhancement of future crucial targets such as biodiversity conservation and the mitigation of global warming effects.
SUTTON, Patrice; WOODRUFF, Tracey J.; PERRON, Joanne; STOTLAND, Naomi; CONRY, Jeanne A.; MILLER, Mark D.; GIUDICE, Linda C.
2015-01-01
Every pregnant woman in the U.S. is exposed to many and varied environmental chemicals. Rapidly accumulating scientific evidence documents that widespread exposure to environmental chemicals at levels encountered in daily life can adversely impact reproductive and developmental health. Preconception and prenatal exposure to environmental chemicals are of particular import because they may have a profound and lasting impact on health across the life course. Thus, preventing developmental exposures to environmental chemicals would benefit greatly from the active participation of reproductive health professionals in clinical and policy arenas. PMID:22405527
Health outcomes of children born after IVF/ICSI: a review of current expert opinion and literature.
Fauser, B C J M; Devroey, P; Diedrich, K; Balaban, B; Bonduelle, M; Delemarre-van de Waal, H A; Estella, C; Ezcurra, D; Geraedts, J P M; Howles, C M; Lerner-Geva, L; Serna, J; Wells, D
2014-02-01
The Sixth Evian Annual Reproduction (EVAR) Workshop Group Meeting was held to evaluate the impact of IVF/intracytoplasmic sperm injection on the health of assisted-conception children. Epidemiologists, reproductive endocrinologists, embryologists and geneticists presented data from published literature and ongoing research on the incidence of genetic and epigenetic abnormalities and congenital malformations in assisted-conception versus naturally conceived children to reach a consensus on the reasons for potential differences in outcomes between these two groups. IVF-conceived children have lower birthweights and higher peripheral fat, blood pressure and fasting glucose concentrations than controls. Growth, development and cognitive function in assisted-conception children are similar to controls. The absolute risk of imprinting disorders after assisted reproduction is less than 1%. A direct link between assisted reproduction and health-related outcomes in assisted-conception children could not be established. Women undergoing assisted reproduction are often older, increasing the chances of obtaining abnormal gametes that may cause deviations in outcomes between assisted-conception and naturally conceived children. However, after taking into account these factors, it is not clear to what extent poorer outcomes are due to the assisted reproduction procedures themselves. Large-scale, multicentre, prospective epidemiological studies are needed to investigate this further and to confirm long-term health consequences in assisted-conception children. Assisted reproduction treatment is a general term used to describe methods of achieving pregnancy by artificial means and includes IVF and sperm implantation. The effect of assisted reproduction treatment on the health of children born using these artificial methods is not fully understood. In April 2011, fertility research experts met to give presentations based on research in this area and to look carefully at the evidence for the effects of assisted reproduction treatment on children's health. The purpose of this review was to reach an agreement on whether there are differences in the health of assisted-conception children with naturally conceived children. The researchers discovered no increased risk in birth defects in assisted-conception children compared with naturally conceived children. They found that IVF-conceived children have lower birth weights and higher fat under the skin, higher blood pressure and higher fasting glucose concentrations than naturally conceived children; however, growth, development and cognitive function are similar between groups. A very low risk of disorders of genetic control was observed in assisted-conception children. Overall, there did not appear to be a direct link between assisted reproduction treatment and children's health. The researchers concluded that the cause of some differences in the health of children conceived using assisted reproduction treatment may be due to the age of the woman receiving treatment. Large-scale, research studies are needed to study the long-term health of children conceived using assisted reproduction treatment. Copyright © 2013 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.
EFFECTS OF ETHYNYL ESTRADIOL EXPOSURE ON REPRODUCTIVE PARAMETERS IN AN ESTUARINE FISH
This study investigated the impact of ethynyl estradiol (EE2) on reproductive success of cunner, Tautogolabrus adspersus. EE2 is the estrogen used in human contraceptives and is released into the aquatic environment in sewage treatment effluent. Reproductively active male and fem...
ERIC Educational Resources Information Center
Manpower Administration (DOL), Washington, DC. Job Corps.
This self-study program for the high-school level contains lessons in the following subjects: Plants and Photosynthesis; The Human Digestive System; Functions of the Blood; Human Circulation and Respiration; Reproduction of a Single Cell; Reproduction by Male and Female Cells; The Human Reproductive System; Genetics and Heredity; The Nervous…
The role of early life nutrition in programming of reproductive function.
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.
Garnier, Jean-Pierre; Klont, Ronald; Plastow, Graham
2003-01-01
Progress in animal nutrition, reproduction, quantitative genetics, and the development of molecular genetics, proteomics, and functional genomics open new perspectives for the meat sector. The most promising developments include a wider utilisation of molecular markers, the possibilities of semen sexing and the targeted use of nutrition to modify the composition of meat. The increased use of biotechnology will have a considerable impact on the economics of production of meat and further processed products. New technologies will increase the possibilities for product differentiation and improve homogeneity of live animals. The consumer and society in general will influence the direction of these developments. This review will focus on the long-term impact of new technologies for the meat production chain.
Auger, Jacques; Eustache, Florence; Rouiller-Fabre, Virginie; Canivenc-Lavier, Marie Chantal; Livera, Gabriel
2014-01-01
In the present review, we first summarize the main benefits, limitations and pitfalls of conventional in vivo approaches to assessing male reproductive structures and functions in rodents in cases of endocrine active substance (EAS) exposure from the postulate that they may provide data that can be extrapolated to humans. Then, we briefly present some integrated approaches in rodents we have recently developed at the organism level. We particularly focus on the possible effects and modes of action (MOA) of these substances at low doses and in mixtures, real-life conditions and at the organ level, deciphering the precise effects and MOA on the fetal testis. It can be considered that the in vivo experimental EAS exposure of rodents remains the first choice for studies and is a necessary tool (together with the epidemiological approach) for understanding the reproductive effects and MOA of EASs, provided the pitfalls and limitations of the rodent models are known and considered. We also provide some evidence that classical rodent models may be refined for studying the multiple consequences of EAS exposure, not only on the reproductive axis but also on various hormonally regulated organs and tissues, among which several are implicated in the complex process of mammalian reproduction. Such models constitute an interesting way of approaching human exposure conditions. Finally, we show that organotypic culture models are powerful complementary tools, especially when focusing on the MOA. All these approaches have contributed in a combinatorial manner to a better understanding of the impact of EAS exposure on human reproduction. PMID:24369134
Leptin and Reproduction: Past Milestones, Present Undertakings and Future Endeavors
Chehab, Farid F.
2014-01-01
The association between leptin and reproduction originated with the leptin-mediated correction of sterility in ob/ob mice and initiation of reproductive function in normal female mice. The uncovering of a central leptin pathway regulating food intake prompted the dissection of neuroendocrine mechanisms involving leptin in the metabolic control of reproduction. The absence of leptin receptors on GnRH neurons incited a search for intermediary neurons situated between leptin responsive and GnRH neurons. This review addresses the most significant findings that have furthered our understanding of recent progress in this new field. The role of leptin in puberty was impacted by the discovery of neurons that co-express kisspeptin, neurokinin B and dynorphin and that could act as leptin intermediates. Furthermore, the identification of first-order leptin-responsive neurons in the premammilary ventral nucleus and other brain regions opens new avenues to explore their relationship to GnRH neurons. Central to these advances is the unveiling that AgRP/NPY neurons project onto GnRH and kisspeptin neurons, allowing a crosstalk between food intake and reproduction. Finally, whereas puberty is a state of leptin sensitivity, mid-gestation represents a state of leptin resistance aimed at building energy stores to sustain pregnancy and lactation. Mechanisms underlying leptin resistance in pregnancy have lagged, however the establishment of this natural state is significant. Reproduction and energy balance are tightly controlled and backed up by redundant mechanisms that are critical for the survival of our species. It will be the goal of the next decade to shed new light on these complex and essential pathways. PMID:25118207
Hoverman, Jason T; Auld, Josh R; Relyea, Rick A
2005-07-01
The last decade has seen an explosion in the number of studies exploring predator-induced plasticity. Recently, there has been a call for more comprehensive approaches that can identify functional relationships between traits, constraints on phenotypic responses, and the cost and benefits of alternative phenotypes. In this study, we exposed Helisoma trivolvis, a freshwater snail, to a factorial combination of three resource levels and five predator environments (no predator, one or two water bugs, and one or two crayfish) and examined ten traits including behavior, morphology, and life history. Each predator induced a unique suite of behavioral and morphological responses. Snails increased near-surface habitat use with crayfish but not with water bugs. Further, crayfish induced narrow and high shells whereas water bugs induced wide shells and wide apertures. In terms of life history, both predators induced delayed reproduction and greater mass at reproduction. However, crayfish induced a greater delay in reproduction that resulted in reduced fecundity whereas water bugs did not induce differences in fecundity. Resource levels impacted the morphology of H. trivolvis; snails reared with greater resource levels produced higher shells, narrower shells, and wider apertures. Resource levels also impacted snail life history; lower resources caused longer times to reproduction and reduced fecundity. Based on an analysis of phenotypic correlations, the morphological responses to each predator most likely represent phenotypic trade-offs. Snails could either produce invasion-resistant shells for defense against water bugs or crush-resistant shells for defense against crayfish, but not both. Our use of a comprehensive approach to examine the responses of H. trivolvis has provided important information regarding the complexity of phenotypic responses to different environments, the patterns of phenotypic integration across environments, and the potential costs and benefits associated with plastic traits.
Potential impact on fertility of new systemic therapies for cystic fibrosis.
Jones, Gareth Huw; Walshaw, Martin John
2015-10-01
Cystic fibrosis is primarily considered a respiratory disease with superadded pancreatic dysfunction; however the underlying genetic mutation results in the abnormal function of cells throughout the body - including tissues involved in reproduction. Practically all males and up to 50% of females with CF will suffer fertility issues - the causes of which are multifactorial and could be improved by treatments that target the underlying physiological deficit, such as ivacaftor. We consider the mechanisms by which the rapidly developing field of systemic treatments for CF could impact on the fertility of this group and review the available real world evidence. Copyright © 2015 Elsevier Ltd. All rights reserved.
This workgroup report addresses the central question: what are the critical windows during development (pre-conception through puberty) when exposure to xenobiotics may have the greatest adverse impact on subsequent reproductive health. The reproductive system develops in stages...
The relationship between gut and adipose hormones, and reproduction.
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.
Benefits and risks of ovarian function and reproduction for cancer development and prevention.
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.
Identification and function of proteolysis regulators in seminal fluid.
Laflamme, Brooke A; Wolfner, Mariana F
2013-02-01
Proteins in the seminal fluid of animals with internal fertilization effect numerous responses in mated females that impact both male and female fertility. Among these proteins is the highly represented class of proteolysis regulators (proteases and their inhibitors). Though proteolysis regulators have now been identified in the seminal fluid of all animals in which proteomic studies of the seminal fluid have been conducted (as well as several other species in which they have not), a unified understanding of the importance of proteolysis to male fertilization success and other reproductive processes has not yet been achieved. In this review, we provide an overview of the identification of proteolysis regulators in the seminal fluid of humans and Drosophila melanogaster, the two species with the most comprehensively known seminal fluid proteomes. We also highlight reports demonstrating the functional significance of specific proteolysis regulators in reproductive and post-mating processes. Finally, we make broad suggestions for the direction of future research into the roles of both active seminal fluid proteolysis regulators and their inactive homologs, another significant class of seminal fluid proteins. We hope that this review aids researchers in pursuing a coordinated study of the functional significance of proteolysis regulators in semen. Copyright © 2012 Wiley Periodicals, Inc.
Chronic exposure to dim light at night suppresses immune responses in Siberian hamsters.
Bedrosian, Tracy A; Fonken, Laura K; Walton, James C; Nelson, Randy J
2011-06-23
Species have been adapted to specific niches optimizing survival and reproduction; however, urbanization by humans has dramatically altered natural habitats. Artificial light at night (LAN), termed 'light pollution', is an often overlooked, yet increasing disruptor of habitats, which perturbs physiological processes that rely on precise light information. For example, LAN alters the timing of reproduction and activity in some species, which decreases the odds of successful breeding and increases the threat of predation for these individuals, leading to reduced fitness. LAN also suppresses immune function, an important proxy for survival. To investigate the impact of LAN in a species naive to light pollution in its native habitat, immune function was examined in Siberian hamsters derived from wild-caught stock. After four weeks exposure to dim LAN, immune responses to three different challenges were assessed: (i) delayed-type hypersensitivity (DTH), (ii) lipopolysaccharide-induced fever, and (iii) bactericide activity of blood. LAN suppressed DTH response and reduced bactericide activity of blood after lipopolysaccharide treatment, in addition to altering daily patterns of locomotor activity, suggesting that human encroachment on habitats via night-time lighting may inadvertently compromise immune function and ultimately fitness.
NASA Astrophysics Data System (ADS)
Lloret, J.; Muñoz, M.; Casadevall, M.
2012-11-01
Artisanal fisheries are frequently considered as a sustainable activity compatible with the conservation objectives of marine protected areas (MPAs). Few studies have examined the impacts of these fisheries on the reproductive potential of exploited fish species within the marine reserves. This study evaluated the potential impact of artisanal fishing on the reproduction of coastal fish species in a Mediterranean MPA through onboard sampling from January 2008 to December 2010. Eleven sex-changing fish species constituted an important part of the catch (20% overall and up to 60% of the total gill net catch) and, in five of them, most individuals were of one sex. Artisanal fishing can negatively affect the sustainability of those coastal fishes showing sex reversal, particularly the protogynous ones such as Diplodus cervinus and Epinephelus marginatus, as well as the species with complex mating systems (e.g. some sparids, labrids and scorpaenids). In all species the average size for the individuals captured was above the minimum landing size (where this exists), but in four species (Conger conger, Diplodus puntazzo, Sphyraena spp. and Sparus aurata) it was below the size of first maturity (L50). Results show that sex and size selection by artisanal fishing not only can have an impact on the reproduction of coastal fish species but may also be exacerbating rather than reducing the impact of fishing on coastal resources. Thus, new management actions need to be urgently implemented in the MPAs where artisanal fisheries are allowed to operate in order to protect the reproductive potential of these species, particularly those showing a complicated reproductive strategy.
Gesquiere, Laurence R.; Onyango, Patrick O.; Alberts, Susan C.; Altmann, Jeanne
2010-01-01
In conditions characterized by energetic constraints, such as in periods of low food availability, some trade-offs between reproduction and self-maintenance may be necessary; even year-round breeders may then be forced to exhibit some reproductive seasonality. Prior research has largely focused on female reproduction and physiology, and few studies have evaluated the impact of environmental factors on males. Here we assessed the effects of season and ambient temperatures on fecal glucocorticoid (fGC) and testosterone (fT) levels in male baboons in Amboseli, Kenya. The Amboseli basin is a highly challenging, semi-arid tropical habitat that is characterized by strongly seasonal patterns of rainfall and by high ambient temperatures. We previously reported that female baboons were impacted by these challenging environmental conditions. We ask here whether male baboons in the same environment and groups as females exhibit similar physiological effects. We found that after accounting for male age and individual variability, males exhibited higher fGC levels and lower fT levels during the dry season than during the wet season. Furthermore, fT but not fGC levels were lower in months of high average daily maximum temperatures, suggesting a direct impact of heat on testes. Our results demonstrate that male baboons, like females, experience ecological stress that alters their reproductive physiology. The impact of the environment on male reproduction deserves more attention both in its own right and because alteration in male physiology may contribute to the reduction in female fertility observed in challenging environments. PMID:20721938
Genetic alterations affecting cholesterol metabolism and human fertility.
DeAngelis, Anthony M; Roy-O'Reilly, Meaghan; Rodriguez, Annabelle
2014-11-01
Single nucleotide polymorphisms (SNPs) represent genetic variations among individuals in a population. In medicine, these small variations in the DNA sequence may significantly impact an individual's response to certain drugs or influence the risk of developing certain diseases. In the field of reproductive medicine, a significant amount of research has been devoted to identifying polymorphisms which may impact steroidogenesis and fertility. This review discusses current understanding of the effects of genetic variations in cholesterol metabolic pathways on human fertility that bridge novel linkages between cholesterol metabolism and reproductive health. For example, the role of the low-density lipoprotein receptor (LDLR) in cellular metabolism and human reproduction has been well studied, whereas there is now an emerging body of research on the role of the high-density lipoprotein (HDL) receptor scavenger receptor class B type I (SR-BI) in human lipid metabolism and female reproduction. Identifying and understanding how polymorphisms in the SCARB1 gene or other genes related to lipid metabolism impact human physiology is essential and will play a major role in the development of personalized medicine for improved diagnosis and treatment of infertility. © 2014 by the Society for the Study of Reproduction, Inc.
Functional Amyloids in Reproduction.
Hewetson, Aveline; Do, Hoa Quynh; Myers, Caitlyn; Muthusubramanian, Archana; Sutton, Roger Bryan; Wylie, Benjamin J; Cornwall, Gail A
2017-06-29
Amyloids are traditionally considered pathological protein aggregates that play causative roles in neurodegenerative disease, diabetes and prionopathies. However, increasing evidence indicates that in many biological systems nonpathological amyloids are formed for functional purposes. In this review, we will specifically describe amyloids that carry out biological roles in sexual reproduction including the processes of gametogenesis, germline specification, sperm maturation and fertilization. Several of these functional amyloids are evolutionarily conserved across several taxa, including human, emphasizing the critical role amyloids perform in reproduction. Evidence will also be presented suggesting that, if altered, some functional amyloids may become pathological.
Influence of environmental factors on college alcohol drinking patterns.
Bani, Ridouan; Hameed, Rasheed; Szymanowski, Steve; Greenwood, Priscilla; Kribs-Zaleta, Christopher M; Mubayi, Anuj
2013-01-01
Alcohol abuse is a major problem, especially among students on and around college campuses. We use the mathematical framework of [16] and study the role of environmental factors on the long term dynamics of an alcohol drinking population. Sensitivity and uncertainty analyses are carried out on the relevant functions (for example, on the drinking reproduction number and the extinction time of moderate and heavy drinking because of interventions) to understand the impact of environmental interventions on the distributions of drinkers. The reproduction number helps determine whether or not the high-risk alcohol drinking behavior will spread and become persistent in the population, whereas extinction time of high-risk drinking measures the effectiveness of control programs. We found that the reproduction number is most sensitive to social interactions, while the time to extinction of high-risk drinkers is significantly sensitive to the intervention programs that reduce initiation, and the college drop-out rate. The results also suggest that in a population, higher rates of intervention programs in low-risk environments (more than intervention rates in high-risk environments) are needed to reduce heavy drinking in the population.
The semenogelins: proteins with functions beyond reproduction?
Jonsson, M; Lundwall, A; Malm, J
2006-12-01
The coagulum proteins of human semen, semenogelins I and II, are secreted in abundance by the seminal vesicles. Their function in reproduction is poorly understood as they are rapidly degraded in ejaculated semen. However, more recent results indicate that it is time to put the semenogelins in a broader physiological perspective that goes beyond reproduction and fertility.
Leptospirosis is strongly associated to estrus repetition on cattle.
Libonati, H A; Santos, G B; Souza, G N; Brandão, F Z; Lilenbaum, W
2018-05-02
Although prevalent, the exact impact of infectious diseases on reproductive failures remains to be determined. Among them, leptospirosis has commonly been reported as cause of abortions on outbreaks. Nevertheless, the majority of the animals present a chronic, silent form of the disease, which is characterized by low reproductive efficiency and is frequently neglected. In that context, we conducted a study that aims to estimate the impact of chronic leptospirosis on reproductive disorders on cattle. A total of 25 different dairy herds with history of reproductive losses from Rio de Janeiro, Brazil, were selected. From each herd, a questionnaire was applied and sera from 20 cows were randomly tested for leptospirosis (totaling 500 cows). Chi-square was performed to estimate the association of seroreactivity with reproductive disorders. A total of 32% of the herds were positive, all of them against serogroup Sejroe. Estrus repetition was the most important reported reproductive problem and it was strongly associated to seroreactivity against leptospirosis. Besides, specific vaccination against leptospirosis was an important protection factor against that disorder. In conclusion, control programs including, but not limited to, vaccines must be implemented on those herds in order to reduce reproductive losses, particularly estrus repetition.
[Astaxanthin in male reproduction: Advances in studies].
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.
Growth Hormone and Reproduction: A Review of Endocrine and Autocrine/Paracrine Interactions
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
Sex-specific inhibition and stimulation of worker-reproductive transition in a termite.
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.
Bioinformatics for spermatogenesis: annotation of male reproduction based on proteomics
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
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...
Electromagnetic field and brain development.
Kaplan, Suleyman; Deniz, Omur Gulsum; Önger, Mehmet Emin; Türkmen, Aysın Pınar; Yurt, Kıymet Kübra; Aydın, Işınsu; Altunkaynak, Berrin Zuhal; Davis, Devra
2016-09-01
Rapid advances in technology involve increased exposures to radio-frequency/microwave radiation from mobile phones and other wireless transmitting devices. As cell phones are held close to the head during talking and often stored next to the reproductive organs, studies are mostly focused on the brain. In fact, more research is especially needed to investigate electromagnetic field (EMF)'s effects on the central nervous system (CNS). Several studies clearly demonstrate that EMF emitted by cell phones could affect a range of body systems and functions. Recent work has demonstrated that EMF inhibit the formation and differentiation of neural stem cells during embryonic development and also affect reproductive and neurological health of adults that have undergone prenatal exposure. The aim of this review is to discuss the developing CNS and explain potential impacts of EMF on this system. Copyright © 2015 Elsevier B.V. All rights reserved.
Nuclear Receptor Coactivator Function in Reproductive Physiology and Behavior
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
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.
Neuroendocrine integration of nutritional signals on reproduction.
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.
Jamal, Farrukh; Haque, Quazi S; Singh, Sangram; Rastogi, S K
2016-08-01
This study is aimed at evaluating the association between occupational exposure to organophosphate (OP) and carbamate (CB) pesticides and semen quality as well as levels of reproductive and thyroid hormones of pesticide sprayers in Malihabad, Lucknow, Uttar Pradesh, India. Thirty-five healthy men (unexposed group) and 64 male pesticide sprayers (exposed group) were recruited for clinical evaluation of fertility status. Fresh semen samples were evaluated for sperm quality and analyzed for DNA fragmentation index (DFI) by flow cytometry. Pesticide exposure was assessed by measuring erythrocyte acetylcholinesterase and plasma butyrylcholinesterase (BuChE) with a Test-mate ChE field kit. Serum levels of total testosterone (Tt), prolactin (PRL), follicle-stimulating hormone (FSH), luteinizing hormone (LH), thyroid-stimulating hormone (TSH), and free thyroxine (FT4) were analyzed using enzyme immunoassay kits. Evidence of pesticide exposure was found in 88.5% of sprayers and significant increments were observed in sperm DFI with significant decrease in some semen parameters. DFI was negatively correlated with BuChE, sperm concentration, morphology, and vitality in these pesticide sprayers. The levels of Tt, PRL, FT4, and TSH appeared to be normal; however, there was a tendency for increased LH and FSH levels in exposed workers. The results confirm the potential impact of chronic occupational exposure to OP and CB pesticides on male reproductive function, which may cause damage to sperm chromatin, decrease semen quality, and produce alterations in reproductive hormones, leading to adverse reproductive health outcomes. © The Author(s) 2015.
Ethical Issues of Reproductive Technologies: Legal and Ethical.
ERIC Educational Resources Information Center
Kammler, Kim
Ethical issues which surround the reproductive technologies being used to assist infertile couples include social impact, surrogacy, access to service and confidentiality. The use of reproductive technologies does not appear to cause harm, and often does a lot of good for the family and society. Surrogacy could be a valuable tool for the infertile…
Toxic plants: Effects on reproduction and fetal and embryonic development in livestock
USDA-ARS?s Scientific Manuscript database
Reproductive performance not only relates to an animal’s ability to produce offspring, but to produce it at a proper time interval and provide proper neonatal care and nutrition. The recognition that poisonous plants may have a major impact on reproductive performance is relatively new and not full...
Ruiz-Pérez, Isabel; Ricci-Cabello, Ignacio; Plazaola-Castaño, Juncal; Montero-Piñar, María Isabel; Escribá-Agüir, Vicenta
2011-12-01
Studies have shown that some sociodemographic factors, such as marital status, employment status or social class, can affect mental health in different ways for each gender. However, up until now, few research projects have tried to ascertain if the role that reproductive work or psychosocial factors play in mental health is different for men and women. The aim of this study is to assess the differences between men and women in terms of how reproductive work, sociodemographic and psychosocial factors are linked to psychological distress in Spain. A cross-sectional study of 29,478 male and female adults using data gathered for the Spanish National Health Survey 2006 was carried out. Psychological distress was measured using the GHQ-12. The independent variables analyzed were: sociodemographic, psychosocial (family functionality and functional social support) and those related to reproductive work (living with or being in charge of different types of people needing care and number of hours devoted to caregiver tasks). Different independent logistic regression models were developed for men and women. In general, with the exception of men who were more prone to psychological distress if they were signed off work for 3 months or more, no major differences were observed regarding the effect of sociodemographic and psychosocial characteristics on psychological distress. With regard to reproductive work, the likelihood of psychological distress doubles in both sexes when the person lives with someone who needs care. In women, a greater number of hours devoted to caring for another person is associated with an increase in distress. Men play a less frequent role in caregiving, but the impact on psychological distress is similar to that in women. Women experienced more psychological distress when they had to live with or be in charge of a disabled person or different types of persons needing care, while men were not affected by this. Major differences have been identified in terms of psychological distress in women and men in several aspects of reproductive work to date unexplored.
DO BODY WEIGHT CHANGES IMPACT AGE OF PUBERTY AND REPRODUCTIVE ENDPOINTS IN THE EDSP TIER 1 MALE AND FEMALE PUBERTAL PROTOCOLS? T.E. Stoker, K. McElroy, J. Ferrell, K. Bremser, R. Cooper and S.C. Laws. Endocrinology Branch, RTD, NHEERL, ORD, USEPA, RTP, NC.
The relations...
Lopez, Terry; Schriner, Samuel E.; Okoro, Michael; Lu, David; Chiang, Beatrice T.; Huey, Jocelyn
2014-01-01
Abstract Green tea is a popular beverage believed to have many health benefits, including a reduction in the risks of heart disease and cancer. Rich in polyphenolic compounds known as catechins, green tea and its components have been shown to increase the lifespan of various animal models, including Drosophila melanogaster. Here, we investigated the gender-specific effects of green tea on the lifespan of fruit flies and observed that green tea extended the lifespan of male flies only. This effect was found to be independent of typical aging interventions, such as dietary restriction, modulation of oxidative energy metabolism, and improved tolerance to environmental stresses. The one exception was that green tea did protect male flies against iron toxicity. Since there is an inverse correlation between lifespan and reproduction, the impact of green tea on male reproductive fitness was also investigated. We found that green tea negatively impacted male fertility as shown by a reduced number of offspring produced and increased mating latency. We further identified that the lifespan extension properties of green tea was only observed in the presence of females which alludes to a reproductive (or mating) dependent mechanism. Our findings suggest that green tea extends the lifespan of male flies by inhibiting reproductive potential, possibly by limiting iron uptake. To our knowledge, our study is the first to report the negative impact of green tea on Drosophila male reproduction. Our results also support previous studies that suggest that green tea might have a negative effect on reproductive fitness in humans. PMID:25058464
Functional study of Cordyceps sinensis and cordycepin in male reproduction: A review.
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.
Leptin and its potential interest in assisted reproduction cycles.
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.
Dynamics of an epidemic model with quarantine on scale-free networks
NASA Astrophysics Data System (ADS)
Kang, Huiyan; Liu, Kaihui; Fu, Xinchu
2017-12-01
Quarantine strategies are frequently used to control or reduce the transmission risks of epidemic diseases such as SARS, tuberculosis and cholera. In this paper, we formulate a susceptible-exposed-infected-quarantined-recovered model on a scale-free network incorporating the births and deaths of individuals. Considering that the infectivity is related to the degrees of infectious nodes, we introduce quarantined rate as a function of degree into the model, and quantify the basic reproduction number, which is shown to be dependent on some parameters, such as quarantined rate, infectivity and network structures. A theoretical result further indicates the heterogeneity of networks and higher infectivity will raise the disease transmission risk while quarantine measure will contribute to the prevention of epidemic spreading. Meanwhile, the contact assumption between susceptibles and infectives may impact the disease transmission. Furthermore, we prove that the basic reproduction number serves as a threshold value for the global stability of the disease-free and endemic equilibria and the uniform persistence of the disease on the network by constructing appropriate Lyapunov functions. Finally, some numerical simulations are illustrated to perform and complement our analytical results.
Novel function of LHFPL2 in female and male distal reproductive tract development.
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.
MicroRNA regulation of immune events at conception.
Robertson, Sarah A; Zhang, Bihong; Chan, Honyueng; Sharkey, David J; Barry, Simon C; Fullston, Tod; Schjenken, John E
2017-09-01
The reproductive tract environment at conception programs the developmental trajectory of the embryo, sets the course of pregnancy, and impacts offspring phenotype and health. Despite the fundamental importance of this stage of reproduction, the rate-limiting regulatory mechanisms operating locally to control fertility and fecundity are incompletely understood. Emerging studies highlight roles for microRNAs (miRNAs) in regulating reproductive and developmental processes and in modulating the quality and strength of the female immune response. Since endometrial receptivity and robust placentation require specific adaptation of the immune response, we hypothesize that miRNAs participate in establishing pregnancy through effects on key gene networks in immune cells. Our recent studies investigated miRNAs that are induced in the peri-conception environment, focusing on miRNAs that have immune-regulatory roles-particularly miR-223, miR-155, and miR-146a. Genetic mouse models deficient in individual miRNAs are proving informative in defining roles for these miRNAs in the generation and stabilization of regulatory T cells (Treg cells) that confer adaptive immune tolerance. Overlapping and redundant functions between miRNAs that target multiple genes, combined with multiple miRNAs targeting individual genes, indicate complex and sensitive regulatory networks. Although to date most data on miRNA regulation of reproductive events are from mice, conserved functions of miRNAs across species imply similar biological pathways operate in all mammals. Understanding the regulation and roles of miRNAs in the peri-conception immune response will advance our knowledge of how environmental determinants act at conception, and could have practical applications for animal breeding as well as human fertility. © 2017 Wiley Periodicals, Inc.
Yimam, Mesfin; Lee, Young-Chul; Hyun, Eu-Jin; Jia, Qi
2015-08-01
In recent years, high prevalence of adverse effects associated to the use of traditional medicines during pregnancy is becoming alarming due to the self-medication of oral supplements by expecting mothers without supervision. Many expectant mothers use alternative and complementary medicines as a supplement to conventional pregnancy management with an inherent belief of considering herbal remedies as harmless. To the contrary, herbal remedies could incur a potential teratogenic risk both to the child bearing mother and the developing fetuses when consumed before or at the time of gestation. Here, we describe the potential adverse effects of orally administered UP446, a standardized bioflavonoid composition from the roots of Scutellaria baicalensis and the heartwoods of Acacia catechu, on fertility and early embryonic development to implantation in Sprague Dawley rats at doses of 250, 500, and 1000 mg/kg. Besides body weight and food consumption, reproductive functions, sperm motility and morphology, estrus cycle, and fertility rate were monitored. There were no statistically significant differences in reproductive function in all UP446 treated groups in both genders. Test substance impacts on reproductive parameters were very minimal. Neither sperm motility nor morphology was affected as a result of oral UP446 administrations in males. There were no treatment-related effects on estrus cycle stages in females. No significant changes in necropsy or histopathology were observed for all the groups. Therefore, the no observed adverse effect level (NOAEL) of UP446 was considered to be 1000 mg/kg, the highest dose tested, in both genders. © 2015 Wiley Periodicals, Inc.
The reach and impact of social marketing and reproductive health communication campaigns in Zambia
Van Rossem, Ronan; Meekers, Dominique
2007-01-01
Background Like many sub-Saharan African countries, Zambia is dealing with major health issues, including HIV/AIDS, family planning, and reproductive health. To address reproductive health problems and the HIV/AIDS epidemic in Zambia, several social marketing and health communication programs focusing on reproductive and HIV/AIDS prevention programs are being implemented. This paper describes the reach of these programs and assesses their impact on condom use. Methods This paper assesses the reach of selected radio and television programs about family planning and HIV/AIDS and of communications about the socially marketed Maximum condoms in Zambia, as well as their impact on condom use, using data from the 2001–2002 Zambia Demographic and Health Survey. To control for self-selection and endogeneity, we use a two-stage regression model to estimate the effect of program exposure on the behavioural outcomes. Results Those who were exposed to radio and television programs about family planning and HIV/AIDS were more likely to have ever used a condom (OR = 1.16 for men and 1.06 for women). Men highly exposed to Maximum condoms social marketing communication were more likely than those with low exposure to the program to have ever used a condom (OR = 1.48), and to have used a condom at their last sexual intercourse (OR = 1.23). Conclusion Findings suggest that the reproductive health and social marketing campaigns in Zambia reached a large portion of the population and had a significant impact on condom use. The results suggest that future reproductive health communication campaigns that invest in radio programming may be more effective than those investing in television programming, and that future campaigns should seek to increase their impact among women, perhaps by focusing on the specific constrains that prevent females from using condoms. PMID:18088437
No sweat: managing menopausal symptoms at work.
Hickey, Martha; Riach, Kathleen; Kachouie, Reza; Jack, Gavin
2017-09-01
Menopause usually occurs between the ages of 45 and 55, a time when women are likely to be in the paid workforce. Most women have menopausal symptoms and these may impact on daytime function and work performance. This study examines the relationship between reproductive stage, menopausal symptoms and work, and advises how employers can best support menopausal women. An online and paper-based survey was completed in 2015-16 by 1092 women (22% response rate) aged 40 years plus employed in three hospitals in metropolitan Australia. Survey questions examined demographics, health and lifestyle variables, menopausal symptom reporting, and work-related variables. Reproductive stage was determined using modified STRAW +10 principal and descriptive criteria. Reproductive stage was not significantly associated with work engagement, organizational commitment, job satisfaction, work limitations and perceived supervisor support. Postmenopausal women had lower intention to leave their organizations than pre- and peri-menopausal women. While sleep problems were the most commonly reported menopausal symptom by peri-menopausal women, for postmenopausal women it was joint and muscular discomfort. Only hot flushes and vaginal dryness were significantly more frequent in peri- and post, compared to pre-menopausal women. In general, women rated their work performance as high and did not feel that menopausal symptoms impaired their work ability. Most women would appreciate greater organizational support, specifically temperature control, flexible work hours and information about menopause for employees and managers. Most women did not believe that menopausal symptoms negatively impacted on their work. Organizational changes may reduce the burden of menopausal symptoms in the workplace.
Kopylov, Uri; Avidan, Benjamin; Papageorgiou, Neofytos P; Katz, Lior H; Sivan, Eyal; Zimlichman, Eyal; Hussein, Haya; Maor, Yaakov
2013-02-01
To examine the prevalence, etiology, risk factors, and outcomes of liver abnormality in pregnancy, in a tertiary medical center, and to study the potential impact of artificial reproduction techniques (ART) on the incidence and the outcome of pregnancy-related liver abnormality. A retrospective case-control study using an electronic database and patients' files. Tertiary referral center. Women in the third trimester of pregnancy who were hospitalized for delivery. None. Development of significant elevation of alanine aminotransferase (ALT ≥ 100 IU/L). Secondary outcomes included development of maternal and fetal complications. The upper limit of normal of ALT was ≥ 1.5 times and it occurred in 440 (1.6%) pregnancies; of those, 228 (0.8%) had ALT ≥ 100 IU/L. The etiology of significant liver test abnormality was idiopathic in 47% of patients. Compared with spontaneous pregnancies (295/23,793), ART was significantly associated with liver test abnormality (145/4, 520). The presence of ALT ≥ 100 IU/L in the third trimester was associated with higher rates of cesarean sections, prematurity, low birthweight, and fetal complications. A definite etiology was not determined in about half of pregnancy-associated liver test abnormality. The ART was significantly associated with liver test elevation. Significant liver test abnormality in the third trimester may have an impact on maternal and fetal/neonatal outcomes. Copyright © 2013 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.
Human spermatozoa: revelations on the road to conception.
Aitken, R John
2013-10-01
Human spermatozoa are highly complex specialized cells designed to survive a long and perilous journey from the site of insemination to the upper reaches of the female reproductive tract where fertilization occurs. During this journey, these cells have to run the gauntlet laid down by the female immune system and time their physiological maturation so that as soon as an egg appears in the Fallopian tube, they are equipped to recognize this cell and participate in a remarkable cascade of cellular interactions culminating in fertilization. Despite their high level of specialization, human spermatozoa are notoriously inadequate and appear to be major contributors to the poor fertility that characterizes our species. Defective spermatozoa are also known to have a major impact on the progress of pregnancy and the health trajectory of the offspring, resulting in paternally mediated increases in miscarriage rate and a range of diseases in the progeny, including dominant genetic diseases and cancer. The causes of defective sperm function are complex and involve both genetic and environmental impacts, as well as paternal age. Where genetic factors are involved, there is a concern that the widespread use of assisted conception technologies will serve to enhance the retention of poor fertility genes in the population such that the more we use assisted reproductive technologies in one generation the more we shall need them in the next. These observations may have important implications for the health and well-being of children and for the provision of reproductive healthcare services for future generations.
Diabetes-induced hyperglycemia impairs male reproductive function: a systematic review.
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 of 890 articles were identified of which 197 (32 clinical, 165 animal studies) were selected for qualitative analysis. While the clinical data from men with hyperglycemia-induced reproductive dysfunction were reported in most studies on T1D, the study designs were variable and lacked complete information on patients. Moreover, only a few studies (and mostly animal studies) addressed the underlying mechanisms of how hyperglycemia induces infertility. Potential causes included impaired function of the hypothalamic-pituitary-gonadal axis, increased DNA damage, perturbations in the system of advanced glycation endproducts and their receptor, oxidative stress, increased endoplasmatic reticulum stress, modulation of cellular pathways, impaired mitochondrial function and disrupted sympathetic innervation. However, intervention studies to identify and confirm the pathological mechanisms were missing: data that are essential in understanding these interactions. While the effects of regulating the hyperglycemia by the use of insulin and other modulators of glucose metabolism have been reported, more clinical trials providing high quality evidence and specifically addressing the beneficial effects on male reproduction are required. We conclude that interventions using insulin to restore normoglycemia should be a feasible approach to assess the proposed underlying mechanisms of infertility. © The Author 2017. 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
Hanus, Robert; Vrkoslav, Vladimír; Hrdý, Ivan; Cvačka, Josef; Šobotník, Jan
2010-01-01
In 1959, P. Karlson and M. Lüscher introduced the term ‘pheromone’, broadly used nowadays for various chemicals involved in intraspecific communication. To demonstrate the term, they depicted the situation in termite societies, where king and queen inhibit the reproduction of nest-mates by an unknown chemical substance. Paradoxically, half a century later, neither the source nor the chemical identity of this ‘royal’ pheromone is known. In this study, we report for the first time the secretion of polar compounds of proteinaceous origin by functional reproductives in three termite species, Prorhinotermes simplex, Reticulitermes santonensis and Kalotermes flavicollis. Aqueous washes of functional reproductives contained sex-specific proteinaceous compounds, virtually absent in non-reproducing stages. Moreover, the presence of these compounds was clearly correlated with the age of reproductives and their reproductive status. We discuss the putative function of these substances in termite caste recognition and regulation. PMID:19939837
Koppik, Mareike; Fricke, Claudia
2017-12-01
Senescence is accompanied by loss of reproductive functions. Here, we studied reproductive ageing in Drosophila melanogaster males and asked whether the expected decline in male reproductive success is due to diminished functionality of the male accessory gland (AG). The male AG produces the majority of seminal fluid proteins (SFPs) transferred to the female at mating. SFPs induce female postmating changes and are key to male reproductive success. We measured age-dependent gene expression changes for five representative SFP genes in males from four different age groups ranging from 1 to 6 weeks after eclosion. Simultaneously, we also measured male reproductive success in postmating traits mediated by transfer of these five SFPs. We found a decreased in male SFP gene expression with advancing age and an accompanying decline in male postmating success. Hence, male reproductive senescence is associated with a decline in functionality of the male AG. While overall individual SFP genes decreased in expression, our results point towards the idea that the composition of an ejaculate might change with male age as the rate of change was variable for those five genes. © 2017 John Wiley & Sons Ltd.
Trends in clinical reproductive medicine research: 10 years of growth.
Aleixandre-Benavent, Rafael; Simon, Carlos; Fauser, Bart C J M
2015-07-01
To study the most important metrics of publication in the field of reproductive medicine over the decade 2003-2012 to aid in discerning the clinical, social, and epidemiologic implications of this relatively new but rapidly emerging area in medical sciences. Bibliometric analysis of most-cited publications from Web of Science databases. Not applicable. None. None. Most productive and frequently cited investigators, institutions, and countries and specific areas of research, scientific collaborations, and comparison of the growth of reproductive medicine research compared with other areas of medical investigation such as obstetrics and gynecology and related science categories. We found that 90 investigators with more than 1,000 citations had jointly published 4,010 articles. A continued rise in the impact factor of reproductive medicine journals was seen. The number of publications in reproductive medicine grew more rapidly compared with other science categories. Presently 22% of highly cited articles in reproductive medicine research are published in journals belonging to science categories outside reproductive medicine. The most-cited study groups are situated in the Netherlands, Belgium, Spain, the United States, and the United Kingdom, and collaborative studies have been increasing. Reproductive medicine research and subsequent clinical development have attained scientific growth and maturity. High-quality research is increasingly being published in high-impact journals. The increase in (inter)national collaborations seems to be key to the field's success. Copyright © 2015 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.
Evolution of reproductive proteins from animals and plants.
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.
Impact of Seed Predators on the Herb Baptisia Lanceolata (Fabales: Fabaceae)
Scott Horn; James L. Hanula
2004-01-01
The reproductive success of plants is a complex interaction among beneficial organisms such as pollinators, and destructive ones such as defoliators or seed predators that eat plant tissue. Many insects that consume reproductive tissue destroy much of a plant's reproductive output (Breedlove & Ehrlich 1968; Janzen 1971; Evans et al. 1989). In particular, the...
The multi-generation reproductive toxicity study (OECD TG 416 and USEPA 870.3800) has been extensively used internationally to assess the adverse effects of substances on reproduction. Recently the necessity of producing a second generation to assess the potential for human healt...
Chehab, Farid F
2014-10-01
The association between leptin and reproduction originated with the leptin-mediated correction of sterility in ob/ob mice and initiation of reproductive function in normal female mice. The uncovering of a central leptin pathway regulating food intake prompted the dissection of neuroendocrine mechanisms involving leptin in the metabolic control of reproduction. The absence of leptin receptors on GnRH neurons incited a search for intermediary neurons situated between leptin-responsive and GnRH neurons. This review addresses the most significant findings that have furthered our understanding of recent progress in this new field. The role of leptin in puberty was impacted by the discovery of neurons that co-express kisspeptin, neurokinin B, and dynorphin and these could act as leptin intermediates. Furthermore, the identification of first-order leptin-responsive neurons in the premammilary ventral nucleus and other brain regions opens new avenues to explore their relationship to GnRH neurons. Central to these advances is the unveiling that agouti-related protein/neuropeptide Y neurons project onto GnRH and kisspeptin neurons, allowing for a crosstalk between food intake and reproduction. Finally, while puberty is a state of leptin sensitivity, mid-gestation represents a state of leptin resistance aimed at building energy stores to sustain pregnancy and lactation. The mechanisms underlying leptin resistance in pregnancy have lagged; however, the establishment of this natural state is significant. Reproduction and energy balance are tightly controlled and backed up by redundant mechanisms that are critical for the survival of our species. It will be the goal of the following decade to shed new light on these complex and essential pathways. © 2014 Society for Endocrinology.
Rusakaniko, S; Mbizvo, M T; Kasule, J; Gupta, V; Kinoti, S N; Mpanju-Shumbushu, W; Sebina-Zziwa, J; Mwateba, R; Padayachy, J
1997-01-01
Unwanted teenage pregnancy, sexually transmitted infections and the attendant morbidity and mortality necessitate the need for understanding factors influencing adolescent sexuality and the implementation of programmes designed to improve their knowledge, reproductive behaviour, sexual and reproductive health. To determine the impact of an intervention package on knowledge levels of various reproductive health issues through trend analysis. Randomized controlled trial of a health education intervention in schools stratified for representativeness. Rural and urban secondary schools in Zimbabwe. 1,689 students recruited from 11 secondary schools in Mashonaland Central. Knowledge level before and after intervention. The demographic characteristics of the pupils at baseline, five months and nine months were comparable between the two groups. There was an overall increase in knowledge on menstruation. Students from the intervention schools were more likely to have correct knowledge over time on aspects of reproductive biology. A significant linear trend (p = 0.017) was observed in the area of family planning and contraception. A linear decreasing trend (p = 0.001) was observed on pregnancy risk. Though not significantly linear, the general trend of knowledge levels in all the areas of reproductive health, pregnancy risk, STDs and HIV/AIDS showed an upward trend, from 20% to 96%. Worth noting was that in all the areas the intervention group had knowledge above that in the control group. The reproductive health education intervention had an impact on aspects of reproductive biology and contraception as measured by the increased scoring at follow up when comparing intervention and control schools. The overall findings point to the need for early school based reproductive health education programmes incooperating correct information on reproductive biology and the prevention of subsequent reproductive morbidity by imparting information on non-risk behaviour during the early developmental years.
Toxicity of Nanoparticles on the Reproductive System in Animal Models: A Review.
Brohi, Rahim Dad; Wang, Li; Talpur, Hira Sajjad; Wu, Di; Khan, Farhan Anwar; Bhattarai, Dinesh; Rehman, Zia-Ur; Farmanullah, F; Huo, Li-Jun
2017-01-01
In the last two decades, nanotechnologies demonstrated various applications in different fields, including detection, sensing, catalysis, electronics, and biomedical sciences. However, public concerns regarding the well-being of human may hinder the wide utilization of this promising innovation. Although, humans are exposed to airborne nanosized particles from an early age, exposure to such particles has risen dramatically within the last century due to anthropogenic sources of nanoparticles. The wide application of nanomaterials in industry, consumer products, and medicine has raised concerns regarding the potential toxicity of nanoparticles in humans. In this review, the effects of nanomaterials on the reproductive system in animal models are discussed. Females are particularly more vulnerable to nanoparticle toxicity, and toxicity in this population may affect reproductivity and fetal development. Moreover, various types of nanoparticles have negative impacts on male germ cells, fetal development, and the female reproductive system. These impacts are associated with nanoparticle modification, composition, concentration, route of administration, and the species of the animal. Therefore, understanding the impacts of nanoparticles on animal growth and reproduction is essential. Many studies have examined the effects of nanoparticles on primary and secondary target organs, with a concentration on the in vivo and in vitro effects of nanoparticles on the male and female reproductive systems at the clinical, cellular, and molecular levels. This review provides important information regarding organism safety and the potential hazards of nanoparticle use and supports the application of nanotechnologies by minimizing the adverse effects of nanoparticles in vulnerable populations.
Toxicity of Nanoparticles on the Reproductive System in Animal Models: A Review
Brohi, Rahim Dad; Wang, Li; Talpur, Hira Sajjad; Wu, Di; Khan, Farhan Anwar; Bhattarai, Dinesh; Rehman, Zia-Ur; Farmanullah, F.; Huo, Li-Jun
2017-01-01
In the last two decades, nanotechnologies demonstrated various applications in different fields, including detection, sensing, catalysis, electronics, and biomedical sciences. However, public concerns regarding the well-being of human may hinder the wide utilization of this promising innovation. Although, humans are exposed to airborne nanosized particles from an early age, exposure to such particles has risen dramatically within the last century due to anthropogenic sources of nanoparticles. The wide application of nanomaterials in industry, consumer products, and medicine has raised concerns regarding the potential toxicity of nanoparticles in humans. In this review, the effects of nanomaterials on the reproductive system in animal models are discussed. Females are particularly more vulnerable to nanoparticle toxicity, and toxicity in this population may affect reproductivity and fetal development. Moreover, various types of nanoparticles have negative impacts on male germ cells, fetal development, and the female reproductive system. These impacts are associated with nanoparticle modification, composition, concentration, route of administration, and the species of the animal. Therefore, understanding the impacts of nanoparticles on animal growth and reproduction is essential. Many studies have examined the effects of nanoparticles on primary and secondary target organs, with a concentration on the in vivo and in vitro effects of nanoparticles on the male and female reproductive systems at the clinical, cellular, and molecular levels. This review provides important information regarding organism safety and the potential hazards of nanoparticle use and supports the application of nanotechnologies by minimizing the adverse effects of nanoparticles in vulnerable populations. PMID:28928662
Experimental reduction of intromittent organ length reduces male reproductive success in a bug
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
Influence of body condition on reproductive output in the guinea pig.
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.
Genetic Alterations Affecting Cholesterol Metabolism and Human Fertility1
DeAngelis, Anthony M.; Roy-O'Reilly, Meaghan; Rodriguez, Annabelle
2014-01-01
ABSTRACT Single nucleotide polymorphisms (SNPs) represent genetic variations among individuals in a population. In medicine, these small variations in the DNA sequence may significantly impact an individual's response to certain drugs or influence the risk of developing certain diseases. In the field of reproductive medicine, a significant amount of research has been devoted to identifying polymorphisms which may impact steroidogenesis and fertility. This review discusses current understanding of the effects of genetic variations in cholesterol metabolic pathways on human fertility that bridge novel linkages between cholesterol metabolism and reproductive health. For example, the role of the low-density lipoprotein receptor (LDLR) in cellular metabolism and human reproduction has been well studied, whereas there is now an emerging body of research on the role of the high-density lipoprotein (HDL) receptor scavenger receptor class B type I (SR-BI) in human lipid metabolism and female reproduction. Identifying and understanding how polymorphisms in the SCARB1 gene or other genes related to lipid metabolism impact human physiology is essential and will play a major role in the development of personalized medicine for improved diagnosis and treatment of infertility. PMID:25122065
Obesity, male infertility, and the sperm epigenome.
Craig, James R; Jenkins, Timothy G; Carrell, Douglas T; Hotaling, James M
2017-04-01
Obesity is a growing epidemic and a common problem among reproductive-age men that can both cause and exacerbate male-factor infertility by means of endocrine abnormalities, associated comorbidities, and direct effects on the fidelity and throughput of spermatogenesis. Robust epidemiologic, clinical, genetic, epigenetic, and nonhuman animal data support these findings. Recent works in the burgeoning field of epigenetics has demonstrated that paternal obesity can affect offspring metabolic and reproductive phenotypes by means of epigenetic reprogramming of spermatogonial stem cells. Understanding the impact of this reprogramming is critical to a comprehensive view of the impact of obesity on subsequent generations. Furthermore, and perhaps more importantly, conveying the impact of these lifestyle changes on future progeny can serve as a powerful tool for obese men to modify their behavior. Reproductive urologists and endocrinologists must learn to assimilate these new findings to better counsel men about the importance of paternal preconception health, a topic recently being championed by the Centers for Disease Control and Prevention. Copyright © 2017 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.
THE DISCOUNTED REPRODUCTIVE NUMBER FOR EPIDEMIOLOGY
Reluga, Timothy C.; Medlock, Jan; Galvani, Alison
2013-01-01
The basic reproductive number, , and the effective reproductive number, , are commonly used in mathematical epidemiology as summary statistics for the size and controllability of epidemics. However, these commonly used reproductive numbers can be misleading when applied to predict pathogen evolution because they do not incorporate the impact of the timing of events in the life-history cycle of the pathogen. To study evolution problems where the host population size is changing, measures like the ultimate proliferation rate must be used. A third measure of reproductive success, which combines properties of both the basic reproductive number and the ultimate proliferation rate, is the discounted reproductive number . The discounted reproductive number is a measure of reproductive success that is an individual’s expected lifetime offspring production discounted by the background population growth rate. Here, we draw attention to the discounted reproductive number by providing an explicit definition and a systematic application framework. We describe how the discounted reproductive number overcomes the limitations of both the standard reproductive numbers and proliferation rates, and show that is closely connected to Fisher’s reproductive values for different life-history stages PMID:19364158
Incorporating reproductive management of beef heifers into a veterinary practice.
Poock, Scott E; Payne, Craig A
2013-11-01
Veterinarians play an important role in reproductive management of dairy herds across the United States; however, in many cases, their involvement in reproductive management of beef herds has been limited. The reasons for this vary; however, there are ways for veterinarians to become more actively involved in reproductive management of US beef herds. Veterinarians can have an impact on producers' profits by implementing their skills and knowledge to beef heifer development programs. This article provides an overview of the services veterinarians can provide to beef cattle producers that pertain to reproductive management of replacement beef heifers. Published by Elsevier Inc.
Effects and outcomes of third-party reproduction: parents.
Greenfeld, Dorothy A
2015-09-01
Third-party reproduction has introduced a host of changing family constellations. Research has shown that children conceived through third-party reproduction are doing well psychologically and developmentally, but what about their parents? How have they coped with the transition to third-party reproduction? Has the experience impacted their marital stability or the quality of their parenting? This review will address parents of children conceived through oocyte donation, parents of children conceived through gestational surrogacy, and gay male parents of children conceived through oocyte donation and gestational surrogacy. Copyright © 2015 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.
[Impact of sexual and reproductive health theme insertion in the undergraduate medical].
de Medeiros, Robinson Dias; de Azevedo, George Dantas; Maranhão, Técia Maria de Oliveira; Gonçalves, Ana Katherine; Barros, Yasha Emerenciano; de Araújo, Ana Cristina Pinheiro Fernandes; Lima, Stênia Lins Leão
2014-03-01
To evaluate the impact of sexual and reproductive health theme insertion in the undergraduate medical curriculum at a Brazilian public university. We developed an instrument for cognitive assessment in sexual and reproductive health based on the subjects addressed in the optional curriculum component Reproductive Health, resulting in an objective multiple choice test containing 27 items. The selected topics were: human, sexual and reproductive rights (HSRR), sexuality, institutional violence, gender, sexual violence, conception, contraception, abortion/legal interruption of pregnancy, maternal mortality and sexually transmitted infections (STIs) - HIV/AIDS. The subjects were grouped into three dimensions of knowledge: HSRR, legal/institutional and biomedical. Two multivariate models were adjusted in the analysis of covariance. The study included 183 students, 127 of the group who took the elective curriculum course reproductive health (RH Group) and 56 who did not (Non-RH Group). Ninety-six students (52.5%) were males and 87 (47.5%) were females. Mean age was 24.7±1.9 years for the RH Group and 24.4±2.6 for the Non-RH Group. The average performance of the SR Group was higher than that of Non-RH subjects regarding the following subjects: HSRR, sexuality, institutional violence, sexual violence, abortion/legal interruption, and STDs - HIV/AIDS. There was no gender difference in performance, except for the theme maternal mortality, in which males scored worse than females (6.9±0.2 and 7.8±0.2, respectively; p<0.05). The participation of students in the elective curriculum component Reproductive Health was associated with better performance in some dimensions of cognitive assessment, suggesting a positive impact of this initiative on general medical education.
Emelumadu, Obiageli Fidelia; Igwegbe, Anthony Osita; Monago, Ifeoma Nwamaka; Ilika, Amobi Linus
2017-01-01
Background This was a prospective study designed to evaluate the impact of thyroid function abnormalities on reproductive hormones during menstrual cycle in HIV infected females at Nnamdi Azikiwe University Teaching Hospital Nnewi, South-East Nigeria. Methods The study randomly recruited 35 Symptomatic HIV infected females and 35 Symptomatic HIV infected females on antiretroviral therapy (HAART) for not less than six weeks from an HIV clinic and 40 apparently heathy control females among the hospital staff of NAUTH Nnewi. They were all premenopausal females with regular menstrual cycle and aged between 15–45 years. Blood samples were collected at follicular and luteal phases of their menstrual cycle for assay of Thyroid indices (FT3, FT4 and TSH) and Reproductive indices (FSH, LH, Estrogen, Progesterone, Prolactin and Testosterone) using ELISA method. Results The result showed significantly higher FSH and LH but significantly lower progesterone (prog) and estrogen (E2) in the test females compared to control females at both phases of menstrual cycle (P<0.05). There was significantly lower FT3 but significantly higher TSH value in Symptomatic HIV females (P<0.05). FSH, LH and TSH values were significantly lowered while prog and FT3 were significantly higher in Symptomatic HIV on ART compared to Symptomatic HIV females (P<0.05). FT3, FT4, Prog and E2 were inversely correlated while FSH and LH were positively correlated with duration of HIV infection in HIV females (P<0.05 respectively). There was a direct correlation between CD4+ count and FT3 while inverse correlation was found between CD4+ count and TSH levels (P<0.05). Discussion The present study demonstrated hypothyroidism with a significant degree of primary hypogonadism in Symptomatic HIV infected females at both follicular and luteal phases of menstrual cycle which tends to normalize on treatments. PMID:28723963
Heme oxygenase/carbon monoxide in the female reproductive system: an overlooked signalling pathway
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
Gene-environment interaction and male reproductive function
Axelsson, Jonatan; Bonde, Jens Peter; Giwercman, Yvonne L.; Rylander, Lars; Giwercman, Aleksander
2010-01-01
As genetic factors can hardly explain the changes taking place during short time spans, environmental and lifestyle-related factors have been suggested as the causes of time-related deterioration of male reproductive function. However, considering the strong heterogeneity of male fecundity between and within populations, genetic variants might be important determinants of the individual susceptibility to the adverse effects of environment or lifestyle. Although the possible mechanisms of such interplay in relation to the reproductive system are largely unknown, some recent studies have indicated that specific genotypes may confer a larger risk of male reproductive disorders following certain exposures. This paper presents a critical review of animal and human evidence on how genes may modify environmental effects on male reproductive function. Some examples have been found that support this mechanism, but the number of studies is still limited. This type of interaction studies may improve our understanding of normal physiology and help us to identify the risk factors to male reproductive malfunction. We also shortly discuss other aspects of gene-environment interaction specifically associated with the issue of reproduction, namely environmental and lifestyle factors as the cause of sperm DNA damage. It remains to be investigated to what extent such genetic changes, by natural conception or through the use of assisted reproductive techniques, are transmitted to the next generation, thereby causing increased morbidity in the offspring. PMID:20348940
Current knowledge on the melatonin system in teleost fish.
Falcón, J; Migaud, H; Muñoz-Cueto, J A; Carrillo, M
2010-02-01
Melatonin is a much conserved feature in vertebrates that plays a central role in the entrainment of daily and annual physiological rhythms. Investigations aiming at understanding how melatonin mediates the effects of photoperiod on crucial functions and behaviors have been very active in the last decades, particularly in mammals. In fish a clear-cut picture is still missing. Here we review the available data on (i) the sites of melatonin production in fish, (ii) the mechanisms that control its daily and annual rhythms of production and (iii) the characterization of its different receptor subtypes, their location and regulation. The in vivo and in vitro data on melatonin effects on crucial neuroendocrine regulations, including reproduction, growth, feeding and behavioral responses, are also reviewed. Finally we discuss how manipulation of the photic cues impact on fish circannual clock and annual cycle of reproduction, and how this can be used for aquaculture purposes. Copyright 2009 Elsevier Inc. All rights reserved.
Physiological basis of climate change impacts on North American inland fishes
Whitney, James E.; Al-Chokhachy, Robert K.; Bunnell, David B.; Caldwell, Colleen A.; Cooke, Steven J.; Eliason, Erika J.; Rogers, Mark W.; Lynch, Abigail J.; Paukert, Craig P.
2016-01-01
Global climate change is altering freshwater ecosystems and affecting fish populations and communities. Underpinning changes in fish distribution and assemblage-level responses to climate change are individual-level physiological constraints. In this review, we synthesize the mechanistic effects of climate change on neuroendocrine, cardiorespiratory, immune, osmoregulatory, and reproductive systems of freshwater and diadromous fishes. Observed climate change effects on physiological systems are varied and numerous, including exceedance of critical thermal tolerances, decreased cardiorespiratory performance, compromised immune function, and altered patterns of individual reproductive investment. However, effects vary widely among and within species because of species, population, and even sex-specific differences in sensitivity and resilience and because of habitat-specific variation in the magnitude of climate-related environmental change. Research on the interactive effects of climate change with other environmental stressors across a broader range of fish diversity is needed to further our understanding of climate change effects on fish physiology.
NASA Astrophysics Data System (ADS)
Martens, William
2005-04-01
Several attributes of auditory spatial imagery associated with stereophonic sound reproduction are strongly modulated by variation in interaural cross correlation (IACC) within low frequency bands. Nonetheless, a standard practice in bass management for two-channel and multichannel loudspeaker reproduction is to mix low-frequency musical content to a single channel for reproduction via a single driver (e.g., a subwoofer). This paper reviews the results of psychoacoustic studies which support the conclusion that reproduction via multiple drivers of decorrelated low-frequency signals significantly affects such important spatial attributes as auditory source width (ASW), auditory source distance (ASD), and listener envelopment (LEV). A variety of methods have been employed in these tests, including forced choice discrimination and identification, and direct ratings of both global dissimilarity and distinct attributes. Contrary to assumptions that underlie industrial standards established in 1994 by ITU-R. Recommendation BS.775-1, these findings imply that substantial stereophonic spatial information exists within audio signals at frequencies below the 80 to 120 Hz range of prescribed subwoofer cutoff frequencies, and that loudspeaker reproduction of decorrelated signals at frequencies as low as 50 Hz can have an impact upon auditory spatial imagery. [Work supported by VRQ.
Universal coverage and its impact on reproductive health services in Thailand.
Tangcharoensathien, Viroj; Tantivess, Sripen; Teerawattananon, Yot; Auamkul, Nanta; Jongudoumsuk, Pongpisut
2002-11-01
Thailand has recently introduced universal health care coverage for 45 million of its people, financed by general tax revenue. A capitation contract model was adopted to purchase ambulatory and hospital care, and preventive care and promotion, including reproductive health services, from public and private service providers. This paper describes the health financing system prior to universal coverage, and the extent to which Thailand has achieved reproductive health objectives prior to this reform. It then analyses the potential impact of universal coverage on reproductive health services. Whether there are positive or negative effects on reproductive health services will depend on the interaction between three key aspects: awareness of entitlement on the part of intended beneficiaries of services, the response of health care providers to capitation, and the capacity of purchasers to monitor and enforce contracts. In rural areas, the district public health system is the sole service provider and the contractual relationship requires trust and positive engagement with purchasers. We recommend an evidence-based approach to fine-tune the reproductive health services benefits package under universal coverage, as well as improved institutional capacity for purchasers and the active participation of civil society and other partners to empower beneficiaries.
2010-04-23
communities. The major compositional trend of the vegetation over time is toward an increased density of conifers , especially in the Montane zone...important plant or animal species; interfered substantially with wildlife movement or reproductive behavior; resulted in a substantial infusion of...with wildlife movement or reproductive behavior. The MAFT site is adjacent to know PMJM habitat. Potential impacts to vegetation would not be
Ionotropic Chemosensory Receptors Mediate the Taste and Smell of Polyamines.
Hussain, Ashiq; Zhang, Mo; Üçpunar, Habibe K; Svensson, Thomas; Quillery, Elsa; Gompel, Nicolas; Ignell, Rickard; Grunwald Kadow, Ilona C
2016-05-01
The ability to find and consume nutrient-rich diets for successful reproduction and survival is fundamental to animal life. Among the nutrients important for all animals are polyamines, a class of pungent smelling compounds required in numerous cellular and organismic processes. Polyamine deficiency or excess has detrimental effects on health, cognitive function, reproduction, and lifespan. Here, we show that a diet high in polyamine is beneficial and increases reproductive success of flies, and we unravel the sensory mechanisms that attract Drosophila to polyamine-rich food and egg-laying substrates. Using a combination of behavioral genetics and in vivo calcium imaging, we demonstrate that Drosophila uses multisensory detection to find and evaluate polyamines present in overripe and fermenting fruit, their favored feeding and egg-laying substrate. In the olfactory system, two coexpressed ionotropic receptors (IRs), IR76b and IR41a, mediate the long-range attraction to the odor. In the gustatory system, multimodal taste sensation by IR76b receptor and GR66a bitter receptor neurons is used to evaluate quality and valence of the polyamine providing a mechanism for the fly's high attraction to polyamine-rich and sweet decaying fruit. Given their universal and highly conserved biological roles, we propose that the ability to evaluate food for polyamine content may impact health and reproductive success also of other animals including humans.
Wascher, Claudia A. F.; Loretto, Matthias-Claudio; Palme, Rupert; Stoewe, Mareike; Kotrschal, Kurt; Frigerio, Didone
2018-01-01
The reproductive season is energetically costly as revealed by elevated glucocorticoid concentrations, constrained immune functions and an increased risk of infections. Social allies and affiliative interactions may buffer physiological stress responses and thereby alleviate associated effects. In the present study, we investigated the seasonal differences of immune reactive corticosterone metabolite concentrations, endoparasite burden (nematode eggs and coccidian oocysts) and affiliative interactions in northern bald ibis (Geronticus eremita), a critically endangered bird. In total, 43 individually marked focal animals from a free-ranging colony were investigated. The analyses included a description of initiated and received affiliative interactions, pair bond status as well as seasonal patterns of hormone and endoparasite levels. During the reproductive season, droppings contained parasite eggs more often and corticosterone metabolite levels were higher as compared to the period after reproduction. The excretion rate of endoparasite products was lower in paired individuals than in unpaired ones, but paired animals exhibited higher corticosterone metabolite concentrations than unpaired individuals. Furthermore, paired individuals initiated affiliative behaviour more frequently than unpaired ones. This suggests that the reproductive season influences the excretion patterns of endoparasite products and corticosterone metabolites and that affiliative interactions between pair partners may positively affect endoparasite burden during periods of elevated glucocorticoid levels. Being embedded in a pair bond may have a positive impact on individual immune system and parasite resistance. PMID:29364951
Ionotropic Chemosensory Receptors Mediate the Taste and Smell of Polyamines
Üçpunar, Habibe K.; Svensson, Thomas; Quillery, Elsa; Gompel, Nicolas; Ignell, Rickard; Grunwald Kadow, Ilona C.
2016-01-01
The ability to find and consume nutrient-rich diets for successful reproduction and survival is fundamental to animal life. Among the nutrients important for all animals are polyamines, a class of pungent smelling compounds required in numerous cellular and organismic processes. Polyamine deficiency or excess has detrimental effects on health, cognitive function, reproduction, and lifespan. Here, we show that a diet high in polyamine is beneficial and increases reproductive success of flies, and we unravel the sensory mechanisms that attract Drosophila to polyamine-rich food and egg-laying substrates. Using a combination of behavioral genetics and in vivo calcium imaging, we demonstrate that Drosophila uses multisensory detection to find and evaluate polyamines present in overripe and fermenting fruit, their favored feeding and egg-laying substrate. In the olfactory system, two coexpressed ionotropic receptors (IRs), IR76b and IR41a, mediate the long-range attraction to the odor. In the gustatory system, multimodal taste sensation by IR76b receptor and GR66a bitter receptor neurons is used to evaluate quality and valence of the polyamine providing a mechanism for the fly’s high attraction to polyamine-rich and sweet decaying fruit. Given their universal and highly conserved biological roles, we propose that the ability to evaluate food for polyamine content may impact health and reproductive success also of other animals including humans. PMID:27145030
Updates in Reproduction Coming from the Endocannabinoid System
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
NASA Astrophysics Data System (ADS)
Redmond, Laura E.; Loewen, Charlie J. G.; Vinebrooke, Rolf D.
2018-03-01
Cumulative impacts of multiple stressors on freshwater biodiversity and ecosystem function likely increase with elevation, thereby possibly placing alpine communities at greatest risk. Here, consideration of species traits enables stressor effects on taxonomic composition to be translated into potential functional impacts. We analyzed data for 47 taxa across 137 mountain lakes and ponds spanning large latitudinal (491 km) and elevational (1,399 m) gradients in western Canada, to assess regional and local factors of the taxonomic composition and functional structure of zooplankton communities. Multivariate community analyses revealed that small body size, clonal reproduction via parthenogenesis, and lack of pigmentation were species traits associated with both introduced non-native sportfish and also environmental conditions reflecting a warmer and drier climate—namely higher water temperatures, shallower water depths, and more chemically concentrated water. Thus, historical introductions of sportfish appear to have potentially induced greater tolerance in zooplankton communities of future climatic warming, especially in previously fishless alpine lakes. Although alpine lake communities occupied a relatively small functional space (i.e., low functional diversity), they were contained within the broader regional functional structure. Therefore, our findings point to the importance of dispersal by lower montane species to the future functional stability of alpine communities.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Savage, Travis J.; Dunphy, Darren R.; Harbaugh, Svetlana
The remarkable impact encapsulation matrix chemistry can have on the bioactivity and viability of integrated living cells is reported. Two silica chemistries (aqueous silicate and alkoxysilane), and a functional component additive (glycerol), are employed to generate three distinct silica matrices. These matrices are used to encapsulate living E. coli cells engineered with a synthetic riboswitch for cell-based biosensing. Following encapsulation, membrane integrity, reproductive capability, and riboswitch-based protein expression levels and rates are measured over a 5 week period. Striking differences in E. coli bioactivity, viability, and biosensing performance are observed for cells encapsulated within the different matrices. E. coli cellsmore » encapsulated for 35 days in aqueous silicate-based (AqS) matrices showed relatively low membrane integrity, but high reproductive capability in comparison to cells encapsulated in glycerol containing sodium silicate-based (AqS + g) and alkoxysilane-based (PGS) gels. Further, cells in sodium silicate-based matrices showed increasing fluorescence output over time, resulting in a 1.8-fold higher fluorescence level, and a faster expression rate, over cells free in solution. Furthermore, this unusual and unique combination of biological properties demonstrates that careful design of the encapsulation matrix chemistry can improve functionality of the biocomposite material, and result in new and unexpected physiological states.« less
Budke, Jessica M; Goffinet, Bernard; Jones, Cynthia S
2013-05-01
In bryophytes the sporophyte offspring are in contact with, nourished from, and partially surrounded by the maternal gametophyte throughout their lifespan. During early development, the moss sporophyte is covered by the calyptra, a cap of maternal gametophyte tissue that has a multilayered cuticle. In this study the effects on sporophyte offspring fitness of removing the maternal calyptra cuticle, in combination with dehydration stress, is experimentally determined. Using the moss Funaria hygrometrica, calyptra cuticle waxes were removed by chemical extraction and individuals were exposed to a short-term dehydration event. Sporophytes were returned to high humidity to complete development and then aspects of sporophyte survival, development, functional morphology, and reproductive output were measured. It was found that removal of calyptra cuticle under low humidity results in significant negative impacts to moss sporophyte fitness, resulting in decreased survival, increased tissue damage, incomplete sporophyte development, more peristome malformations, and decreased reproductive output. This study represents the strongest evidence to date that the structure of the calyptra cuticle functions in dehydration protection of the immature moss sporophyte. The investment in a maternal calyptra with a multilayered cuticle increases offspring fitness and provides a functional explanation for calyptra retention across mosses. The moss calyptra may represent the earliest occurance of maternal protection via structural provisioning of a cuticle in green plants.
Savage, Travis J.; Dunphy, Darren R.; Harbaugh, Svetlana; ...
2015-11-06
The remarkable impact encapsulation matrix chemistry can have on the bioactivity and viability of integrated living cells is reported. Two silica chemistries (aqueous silicate and alkoxysilane), and a functional component additive (glycerol), are employed to generate three distinct silica matrices. These matrices are used to encapsulate living E. coli cells engineered with a synthetic riboswitch for cell-based biosensing. Following encapsulation, membrane integrity, reproductive capability, and riboswitch-based protein expression levels and rates are measured over a 5 week period. Striking differences in E. coli bioactivity, viability, and biosensing performance are observed for cells encapsulated within the different matrices. E. coli cellsmore » encapsulated for 35 days in aqueous silicate-based (AqS) matrices showed relatively low membrane integrity, but high reproductive capability in comparison to cells encapsulated in glycerol containing sodium silicate-based (AqS + g) and alkoxysilane-based (PGS) gels. Further, cells in sodium silicate-based matrices showed increasing fluorescence output over time, resulting in a 1.8-fold higher fluorescence level, and a faster expression rate, over cells free in solution. Furthermore, this unusual and unique combination of biological properties demonstrates that careful design of the encapsulation matrix chemistry can improve functionality of the biocomposite material, and result in new and unexpected physiological states.« less
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
Gurven, Michael; Costa, Megan; Ben Trumble; Stieglitz, Jonathan; Beheim, Bret; Eid Rodriguez, Daniel; Hooper, Paul L; Kaplan, Hillard
2016-07-20
Women exhibit greater morbidity than men despite higher life expectancy. An evolutionary life history framework predicts that energy invested in reproduction trades-off against investments in maintenance and survival. Direct costs of reproduction may therefore contribute to higher morbidity, especially for women given their greater direct energetic contributions to reproduction. We explore multiple indicators of somatic condition among Tsimane forager-horticulturalist women (Total Fertility Rate = 9.1; n = 592 aged 15-44 years, n = 277 aged 45+). We test whether cumulative live births and the pace of reproduction are associated with nutritional status and immune function using longitudinal data spanning 10 years. Higher parity and faster reproductive pace are associated with lower nutritional status (indicated by weight, body mass index, body fat) in a cross-section, but longitudinal analyses show improvements in women's nutritional status with age. Biomarkers of immune function and anemia vary little with parity or pace of reproduction. Our findings demonstrate that even under energy-limited and infectious conditions, women are buffered from the potential depleting effects of rapid reproduction and compound offspring dependency characteristic of human life histories.
Biomechanics meets the ecological niche: the importance of temporal data resolution.
Kearney, Michael R; Matzelle, Allison; Helmuth, Brian
2012-03-15
The emerging field of mechanistic niche modelling aims to link the functional traits of organisms to their environments to predict survival, reproduction, distribution and abundance. This approach has great potential to increase our understanding of the impacts of environmental change on individuals, populations and communities by providing functional connections between physiological and ecological response to increasingly available spatial environmental data. By their nature, such mechanistic models are more data intensive in comparison with the more widely applied correlative approaches but can potentially provide more spatially and temporally explicit predictions, which are often needed by decision makers. A poorly explored issue in this context is the appropriate level of temporal resolution of input data required for these models, and specifically the error in predictions that can be incurred through the use of temporally averaged data. Here, we review how biomechanical principles from heat-transfer and metabolic theory are currently being used as foundations for mechanistic niche models and consider the consequences of different temporal resolutions of environmental data for modelling the niche of a behaviourally thermoregulating terrestrial lizard. We show that fine-scale temporal resolution (daily) data can be crucial for unbiased inference of climatic impacts on survival, growth and reproduction. This is especially so for species with little capacity for behavioural buffering, because of behavioural or habitat constraints, and for detecting temporal trends. However, coarser-resolution data (long-term monthly averages) can be appropriate for mechanistic studies of climatic constraints on distribution and abundance limits in thermoregulating species at broad spatial scales.
Estimating reproduction numbers for adults and children from case data
Glass, K.; Mercer, G. N.; Nishiura, H.; McBryde, E. S.; Becker, N. G.
2011-01-01
We present a method for estimating reproduction numbers for adults and children from daily onset data, using pandemic influenza A(H1N1) data as a case study. We investigate the impact of different underlying transmission assumptions on our estimates, and identify that asymmetric reproduction matrices are often appropriate. Under-reporting of cases can bias estimates of the reproduction numbers if reporting rates are not equal across the two age groups. However, we demonstrate that the estimate of the higher reproduction number is robust to disproportionate data-thinning. Applying the method to 2009 pandemic influenza H1N1 data from Japan, we demonstrate that the reproduction number for children was considerably higher than that of adults, and that our estimates are insensitive to our choice of reproduction matrix. PMID:21345858
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.
Pradhan, Devaleena S.; Solomon-Lane, Tessa K.; Grober, Matthew S.
2015-01-01
Steroid hormones are critical regulators of reproductive life history, and the steroid sensitive traits (morphology, behavior, physiology) associated with particular life history stages can have substantial fitness consequences for an organism. Hormones, behavior and fitness are reciprocally associated and can be used in an integrative fashion to understand how the environment impacts organismal function. To address the fitness component, we highlight the importance of using reliable proxies of reproductive success when studying proximate regulation of reproductive phenotypes. To understand the mechanisms by which the endocrine system regulates phenotype, we discuss the use of particular endocrine proxies and the need for appropriate functional interpretation of each. Lastly, in any experimental paradigm, the responses of animals vary based on the subtle differences in environmental and social context and this must also be considered. We explore these different levels of analyses by focusing on the fascinating life history transitions exhibited by the bi-directionally hermaphroditic fish, Lythrypnus dalli. Sex changing fish are excellent models for providing a deeper understanding of the fitness consequences associated with behavioral and endocrine variation. We close by proposing that local regulation of steroids is one potential mechanism that allows for the expression of novel phenotypes that can be characteristic of specific life history stages. A comparative species approach will facilitate progress in understanding the diversity of mechanisms underlying the contextual regulation of phenotypes and their associated fitness correlates. PMID:25691855
Pradhan, Devaleena S; Solomon-Lane, Tessa K; Grober, Matthew S
2015-01-01
Steroid hormones are critical regulators of reproductive life history, and the steroid sensitive traits (morphology, behavior, physiology) associated with particular life history stages can have substantial fitness consequences for an organism. Hormones, behavior and fitness are reciprocally associated and can be used in an integrative fashion to understand how the environment impacts organismal function. To address the fitness component, we highlight the importance of using reliable proxies of reproductive success when studying proximate regulation of reproductive phenotypes. To understand the mechanisms by which the endocrine system regulates phenotype, we discuss the use of particular endocrine proxies and the need for appropriate functional interpretation of each. Lastly, in any experimental paradigm, the responses of animals vary based on the subtle differences in environmental and social context and this must also be considered. We explore these different levels of analyses by focusing on the fascinating life history transitions exhibited by the bi-directionally hermaphroditic fish, Lythrypnus dalli. Sex changing fish are excellent models for providing a deeper understanding of the fitness consequences associated with behavioral and endocrine variation. We close by proposing that local regulation of steroids is one potential mechanism that allows for the expression of novel phenotypes that can be characteristic of specific life history stages. A comparative species approach will facilitate progress in understanding the diversity of mechanisms underlying the contextual regulation of phenotypes and their associated fitness correlates.
Avila-Burgos, Leticia; Cahuana-Hurtado, Lucero; Montañez-Hernandez, Julio; Servan-Mori, Edson; Aracena-Genao, Belkis; Del Río-Zolezzi, Aurora
2016-01-01
To analyze whether the changes observed in the level and distribution of resources for maternal health and family planning (MHFP) programs from 2003 to 2012 were consistent with the financial goals of the related policies. A longitudinal descriptive analysis of the Mexican Reproductive Health Subaccounts 2003-2012 was performed by financing scheme and health function. Financing schemes included social security, government schemes, household out-of-pocket (OOP) payments, and private insurance plans. Functions were preventive care, including family planning, antenatal and puerperium health services, normal and cesarean deliveries, and treatment of complications. Changes in the financial imbalance indicators covered by MHFP policy were tracked: (a) public and OOP expenditures as percentages of total MHFP spending; (b) public expenditure per woman of reproductive age (WoRA, 15-49 years) by financing scheme; (c) public expenditure on treating complications as a percentage of preventive care; and (d) public expenditure on WoRA at state level. Statistical analyses of trends and distributions were performed. Public expenditure on government schemes grew by approximately 300%, and the financial imbalance between populations covered by social security and government schemes decreased. The financial burden on households declined, particularly among households without social security. Expenditure on preventive care grew by 16%, narrowing the financing gap between treatment of complications and preventive care. Finally, public expenditure per WoRA for government schemes nearly doubled at the state level, although considerable disparities persist. Changes in the level and distribution of MHFP funding from 2003 to 2012 were consistent with the relevant policy goals. However, improving efficiency requires further analysis to ascertain the impact of investments on health outcomes. This, in turn, will require better financial data systems as a precondition for improving the monitoring and accountability functions in Mexico.
The manuscript reviews the issues concerning the use of results on pesticide effects from laboratory avian reproduction tests for estimating potential impacts of pesticides on fecundity rates in avian population models.
Inflammatory Bowel Disease: Influence and Implications in Reproduction
Glover, Louise E.; Fennimore, Blair; Wingfield, Mary
2016-01-01
The incidence and prevalence of inflammatory bowel disease (IBD) continues to rise with time, signifying its emergence as a global disease. Clinical onset of IBD, comprising Crohn’s disease and ulcerative colitis, typically occurs prior to or at peak reproductive age. Although active disease in female patients is associated with reduced fertility and adverse obstetric outcomes in pregnancy, the molecular mechanisms underlying this altered reproductive course, as well as its impact on IBD transmission to offspring, remain poorly understood. Clinical and experimental studies have now begun to elucidate the hormonal, environmental and microbial factors that modulate immune-reproductive crosstalk in IBD, and define their impact on maternal health, fetal development and heritability of disease risk. Evolving insight into maternal-fetal imprinting in IBD has important implications for patient counseling and disease management during pregnancy, and may help predict clinical outcomes for both mother and child. PMID:27537054
The impact of sex ratio and economic status on local birth rates
Chipman, A.; Morrison, E.
2013-01-01
Human mating and reproductive behaviour can vary depending on various mechanisms, including the local sex ratio. Previous research shows that as sex ratios become female-biased, women from economically deprived areas are less likely to delay reproductive opportunities to wait for a high-investing mate but instead begin their reproductive careers sooner. Here, we show that the local sex ratio also has an impact on female fertility schedules. At young ages, a female-biased ratio is associated with higher birth rates in the poorest areas, whereas the opposite is true for the richest areas. At older ages, a female-biased ratio is associated with higher birth rates in the richest, but not the poorest areas. These patterns suggest that female–female competition encourages poorer women to adopt a fast life-history strategy and give birth early, and richer women to adopt a slow life-history strategy and delay reproduction. PMID:23407502
The impact of sex ratio and economic status on local birth rates.
Chipman, A; Morrison, E
2013-04-23
Human mating and reproductive behaviour can vary depending on various mechanisms, including the local sex ratio. Previous research shows that as sex ratios become female-biased, women from economically deprived areas are less likely to delay reproductive opportunities to wait for a high-investing mate but instead begin their reproductive careers sooner. Here, we show that the local sex ratio also has an impact on female fertility schedules. At young ages, a female-biased ratio is associated with higher birth rates in the poorest areas, whereas the opposite is true for the richest areas. At older ages, a female-biased ratio is associated with higher birth rates in the richest, but not the poorest areas. These patterns suggest that female-female competition encourages poorer women to adopt a fast life-history strategy and give birth early, and richer women to adopt a slow life-history strategy and delay reproduction.
Jenkins, Jill A.; Goodbred, Steven L.; Olivier, Heather M.; Draugelis-Dale, Rassa O.; Alvarez, David A.
2009-01-01
The Santa Ana River (SAR) in southern California is impacted by effluents from wastewater treatment plants (WWTP), which are sources of organic wastewater compounds (OWCs) and urban runoff. The Santa Ana River is one of only three river basins supporting native populations of the federally listed Santa Ana sucker (Catostomus santaanae) at the time the fish was included on the list 2000. In 2004 and 2005, a U.S. Geological Survey and U.S. Fish and Wildlife Service study was undertaken to determine if the threatened Santa Ana sucker was potentially exposed to OWCs and endocrine disrupting compounds (EDCs) in the SAR by using the western mosquitofish (Gambusia affinis) as a surrogate fish model. Four Santa Ana River sites were chosen along a gradient of proximity to WWTP effluents: (1) a point source of tertiary treated wastewater effluent (TTWE), (2) Rialto Drain (just below a WWTP), (3) Prado Dam (11 kilometers [km] below WWTPs), and (4) Sunnyslope Creek (no WWTP but having urban runoff influence). A reference site having no WWTPs or urban runoff, Thousand Palms, was also sampled. Chemical analyses of passive sampler extracts results showed that 15 OWCs and EDCs were detected in water from the Santa Ana River sites. Many of these compounds contributed to activity from an estrogenic in-vitro assay that showed a significant potential for impacting endocrine and reproductive systems compared to the 25 organochlorine compounds detected in aquatic biota. The site showing compounds having highest influence on sex steroid hormone activities was the point source for TTWE. Sex steroid hormone levels, secondary sex characteristics, organosomatic indices, and sperm quality parameters indicated impairment of endocrine and reproductive function of male western mosquitofish in the Santa Ana River. Exposure to EDCs and consequent impairment in mosquitofish followed the gradient of proximity to WWTP effluents, where the most significant effects were found at TTWE point source and Rialto Drain, followed by Prado Dam and Sunnyslope Creek. Each of these sites is suitable habitat for the Santa Ana sucker, especially Sunnyslope Creek and Rialto Drain where juveniles reside. Various OWCs and EDCs were detected at each Santa Ana River site, although one specific compound or group of compounds could not be singled out as a causative factor. Di (2-ethylhexyl) phthalate was strongly negatively correlated with testosterone in male mosquitofish. One group of potent environmental estrogens that likely contributed to endocrine and reproductive impairment are the natural and synthetic estrogen hormones, especially ethinyl estradiol; however, this compound was not targeted in these investigations. The multiple lines of evidence for impaired reproductive and endocrine function in western mosquitofish due to OWCs and EDCs from the Santa Ana River can be used to identify potential problems for the Santa Ana sucker inhabiting the same and nearby sites.
Health Literacy and Women's Reproductive Health: A Systematic Review
Vitko, Michelle; O'Conor, Rachel; Bailey, Stacy Cooper
2016-01-01
Abstract Background: Health literacy is thought to impact women's reproductive health, yet no comprehensive systematic reviews have been conducted on the topic. Our objective was to systematically identify, investigate, and summarize research on the relationship between health literacy and women's reproductive health knowledge, behaviors, and outcomes. Methods: PRISMA guidelines were used to guide this review. English language, peer-reviewed research articles indexed in MEDLINE as of February 2015 were searched, along with study results posted on Clinicaltrials.gov. Articles were included if they (1) described original data-driven research conducted in developed countries, (2) were published in a peer-reviewed journal, (3) measured health literacy using a validated assessment, (4) reported on the relationship between health literacy and reproductive health outcomes, related knowledge, or behaviors, and (5) consisted of a study population that included reproductive age women. Results: A total of 34 articles met eligibility criteria and were included in this review. Data were abstracted from articles by two study authors using a standardized form. Abstracted data were then reviewed and summarized in table format. Overall, health literacy was associated with reproductive health knowledge across a spectrum of topics. It was also related to certain health behaviors, such as prenatal vitamin use and breastfeeding. Its relationship with other reproductive behaviors and outcomes remains unclear. Conclusions: Health literacy plays an important role in reproductive knowledge and may impact behaviors and outcomes. While further research is necessary, healthcare providers should utilize health literacy best practices now to promote high-quality care for patients. PMID:27564780
New, Leslie F.; Moretti, David J.; Hooker, Sascha K.; Costa, Daniel P.; Simmons, Samantha E.
2013-01-01
Mass stranding of several species of beaked whales (family Ziphiidae) associated with exposure to anthropogenic sounds has raised concern for the conservation of these species. However, little is known about the species’ life histories, prey or habitat requirements. Without this knowledge, it becomes difficult to assess the effects of anthropogenic sound, since there is no way to determine whether the disturbance is impacting the species’ physical or environmental requirements. Here we take a bioenergetics approach to address this gap in our knowledge, as the elusive, deep-diving nature of beaked whales has made it hard to study these effects directly. We develop a model for Ziphiidae linking feeding energetics to the species’ requirements for survival and reproduction, since these life history traits would be the most likely to be impacted by non-lethal disturbances. Our models suggest that beaked whale reproduction requires energy dense prey, and that poor resource availability would lead to an extension of the inter-calving interval. Further, given current information, it seems that some beaked whale species require relatively high quality habitat in order to meet their requirements for survival and reproduction. As a result, even a small non-lethal disturbance that results in displacement of whales from preferred habitats could potentially impact a population if a significant proportion of that population was affected. We explored the impact of varying ecological parameters and model assumptions on survival and reproduction, and find that calf and fetus survival appear more readily affected than the survival of adult females. PMID:23874737
Mayhew, Susannah H.; Ploubidis, George B.; Sloggett, Andy; Church, Kathryn; Obure, Carol D.; Birdthistle, Isolde; Sweeney, Sedona; Warren, Charlotte E.; Watts, Charlotte; Vassall, Anna
2016-01-01
Background The body of knowledge on evaluating complex interventions for integrated healthcare lacks both common definitions of ‘integrated service delivery’ and standard measures of impact. Using multiple data sources in combination with statistical modelling the aim of this study is to develop a measure of HIV-reproductive health (HIV-RH) service integration that can be used to assess the degree of service integration, and the degree to which integration may have health benefits to clients, or reduce service costs. Methods and Findings Data were drawn from the Integra Initiative’s client flow (8,263 clients in Swaziland and 25,539 in Kenya) and costing tools implemented between 2008–2012 in 40 clinics providing RH services in Kenya and Swaziland. We used latent variable measurement models to derive dimensions of HIV-RH integration using these data, which quantified the extent and type of integration between HIV and RH services in Kenya and Swaziland. The modelling produced two clear and uncorrelated dimensions of integration at facility level leading to the development of two sub-indexes: a Structural Integration Index (integrated physical and human resource infrastructure) and a Functional Integration Index (integrated delivery of services to clients). The findings highlight the importance of multi-dimensional assessments of integration, suggesting that structural integration is not sufficient to achieve the integrated delivery of care to clients—i.e. “functional integration”. Conclusions These Indexes are an important methodological contribution for evaluating complex multi-service interventions. They help address the need to broaden traditional evaluations of integrated HIV-RH care through the incorporation of a functional integration measure, to avoid misleading conclusions on its ‘impact’ on health outcomes. This is particularly important for decision-makers seeking to promote integration in resource constrained environments. PMID:26800517
Ieromina, O; Musters, C J M; Bodegom, P M; Peijnenburg, W J G M; Vijver, M G
2016-08-01
Analyzing functional species' characteristics (species traits) that represent physiological, life history and morphological characteristics of species help understanding the impacts of various stressors on aquatic communities at field conditions. This research aimed to study the combined effects of pesticides and other environmental factors (temperature, dissolved oxygen, dissolved organic carbon, floating macrophytes cover, phosphate, nitrite, and nitrate) on the trait modality distribution of aquatic macrofauna communities. To this purpose, a field inventory was performed in a flower bulb growing area of the Netherlands with significant variation in pesticides pressures. Macrofauna community composition, water chemistry parameters and pesticide concentrations in ditches next to flower bulb fields were determined. Trait modalities of nine traits (feeding mode, respiration mode, locomotion type, resistance form, reproduction mode, life stage, voltinism, saprobity, maximum body size) likely to indicate pesticides impacts were analyzed. According to a redundancy analysis, phosphate -and not pesticides- constituted the main factor structuring the trait modality distribution of aquatic macrofauna. The functional composition could be ascribed for 2-4 % to pesticides, and for 3-11 % to phosphate. The lack of trait responses to pesticides may indicate that species may have used alternative strategies to adapt to ambient pesticides stress. Biomass of animals exhibiting trait modalities related to feeding by predation and grazing, presence of diapause form or dormancy, reproduction by free clutches and ovoviviparity, life stage of larvae and pupa, was negatively correlated to the concentration of phosphate. Hence, despite the high pesticide pollution in the area, variation in nutrient-related stressors seems to be the dominant driver of the functional composition of aquatic macrofauna assembly in agricultural ditches.
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.
Shortleaf pine reproduction abundance and growth in pine-oak stands in the Missouri Ozarks
Elizabeth M. Blizzard; Doyle Henken; John M. Kabrick; Daniel C. Dey; David R. Larsen; David Gwaze
2007-01-01
We conducted an operational study to evaluate effect of site preparation treatments on pine reproduction density and the impact of overstory basal area and understory density on pine reproduction height and basal diameter in pine-oak stands in the Missouri Ozarks. Stands were harvested to or below B-level stocking, but patchiness of the oak decline lead to some plots...
ATP-binding cassette transporters in reproduction: a new frontier
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 breast cancer-related protein, the multidrug resistance proteins 1 through 5 and the cholesterol transporters ABCA1 and ABCG1. CONCLUSIONS The ABC transporters have various roles across multiple reproductive tissues. Knowledge of efflux direction, tissue distribution, substrate specificity and regulation of the ABC transporters in the placenta and other reproductive tissues is rapidly expanding. This will allow better understanding of the disposition of specific substrates within reproductive tissues, and facilitate development of novel treatments for reproductive disorders as well as improved approaches to protecting the developing fetus. PMID:26545808
Women and Power: Problems of Feminine Pollution.
ERIC Educational Resources Information Center
Michaelson, Evalyn J.
The author reviews cross-cultural studies correlating women's reproductive functions with states of ritual defilement, pollution, and cultural restrictions on social behavior. Women's reproductive functions--childbirth, menstruation, and sexual intercourse--are frequently viewed as contaminating. Thus, during her menstrual period or period…
NASA Astrophysics Data System (ADS)
Ballón, Michael; Wosnitza-Mendo, Claudia; Guevara-Carrasco, Renato; Bertrand, Arnaud
2008-10-01
In this study we examine physiological responses of Peruvian hake ( Merluccius gayi peruanus) to changes in their population structure and physical environment during the period 1971-2004. In particular, we assess the relative investment of energy in growth and/or reproduction of small (20-35 cm) and large (35-50 cm) hake. We calculated the (i) condition (Fulton’s K), (ii) gonad and (iii) gut fullness indices for 42,761 female hakes sampled from commercial landings; these indices indicate fish somatic, reproductive and feeding condition, respectively. Using Generalized Additive Models we then examined potential relationships between these indices and sea surface temperature anomalies and date. Drastic energy exhaustion and a decrease in female hake fecundity were observed during El Niño events. The long-term trend showed a general increase in condition factor and a decrease in gonad index for large hake between 1971 and 2004. Small hake exhibited a different trend with an increase in reproductive activity, which was accompanied by an earlier maturation. We hypothesise that the observed low investment of energy in reproduction by large female hake might be related to the lack of large males, due to a sex-selective fishery and the impact of El Niño. We suggest that fishing diminished hake reproductive capacity, modified the sex ratio in favour of females and increased population vulnerability to environmental stress, in particular to the El Niño. The impact of multidecadal variability and predators like the squid, Dosidicus gigas, remain unresolved until longer time series become available.
Smith, Malcolm K
2012-06-01
On 1 January 2010, the Assisted Reproductive Treatment Act 2008 (Vic) came into force. The legislation was the outcome of a detailed review and consultation process undertaken by the Victorian Law Reform Commission. Arguably, the change to the regulatory framework represents a significant shift in policy compared to previous regulatory approaches on this topic in Victoria. This article considers the impact of the new legislation on eligibility for reproductive treatments, focusing on the accessibility of such services for the purpose of creating a "saviour sibling". It also highlights the impact of the Victorian regulatory body's decision to abolish its regulatory policies on preimplantation genetic diagnosis and preimplantation tissue-typing, concluding that the regulatory approach in relation to these latter issues is similar to other Australian jurisdictions where such practices are not addressed by a statutory framework.
Lind, Tekla; Lampic, Claudia; Hammarström, Margareta; Rodriguez-Wallberg, Kenny
2013-11-01
To investigate young women's reproductive desire and perceptions of fertility-related information when scheduled for ovarian cyst surgery with a possible impact on fertility. Cross-sectional study. University Hospital. Women of reproductive age (n = 106, mean age 32.3 years, range 18-44 years) with a diagnosis of ovarian cyst and scheduled ovarian cyst surgery between March 2011 and September 2012 were included. The women answered a questionnaire after the presurgery consultation with the gynecologist. The questionnaire included study-specific measures of reproductive desire, perception of fertility-related information received, worry about future fertility and sociodemographic characteristics. Reproductive desire and recalled information on the impact of surgery on fertility. A high proportion of the women (72%) reported a desire for having children in the future and more than half of them (58%) recalled receiving information about the impact of surgery on fertility. In a multivariable logistic regression model adjusted for parity, education and age, a desire to have children increased the likelihood of recalling having received fertility-related information (odds ratio 3.2, 95% CI 1.1-9.2). Almost half of women with reproductive desire had ovarian surgery without recalling a discussion of fertility issues. Development of written information or interactive information might improve women's perception of fertility-related information. © 2013 Nordic Federation of Societies of Obstetrics and Gynecology.
Deng, Xiaobao; Mohandass, Dharmalingam; Katabuchi, Masatoshi; Hughes, Alice C; Roubik, David W
2015-01-01
Nectar-robbing has the potential to strongly affect male and female reproductive fitness of plants. One example of nectar theft is that shown by striped-squirrels (Tamiops swinhoei) on a number of ginger species, including Alpinia roxburghii and A. kwangsiensis (Zingiberaceae). In this study, we used a fluorescent dye as a pollen analogue, and measured fruit and seed output, to test the effect of squirrel nectar-robbing on A. roxburghii reproductive fitness. Pollen transfer between robbed and unrobbed flowers was assessed by comparing 60 randomly established plots containing robbed and unrobbed flowers. The frequency of squirrel robbing visits and broken styles were recorded from a number of flowers for five consecutive days. Two bee species (Bombus eximius and Apis cerana), were the primary pollinators, and their visitation frequency was recorded for six consecutive days. The results showed that fluorescent powder from unrobbed flowers was dispersed further, and to a greater number of flowers than that placed on robbed flowers. Additionally, robbing flowers caused significant damage to reproductive organs, resulting in lower fruit and seed sets in robbed than in unrobbed flowers and influencing both male and female fitness. The frequency of the primary pollinator visits (B. eximius) was significantly higher for unrobbed plants than for robbed plants. The present study clearly shows the negative impact of squirrel robbing on A. roxburghii male reproductive fitness and neutral impact on female reproductive fitness.
Zhang, Lai; Andersen, Ken H; Dieckmann, Ulf; Brännström, Åke
2015-09-07
We investigate how four types of interference competition - which alternatively affect foraging, metabolism, survival, and reproduction - impact the ecology and evolution of size-structured populations. Even though all four types of interference competition reduce population biomass, interference competition at intermediate intensity sometimes significantly increases the abundance of adult individuals and the population׳s reproduction rate. We find that foraging and metabolic interference evolutionarily favor smaller maturation size when interference is weak and larger maturation size when interference is strong. The evolutionary response to survival interference and reproductive interference is always larger maturation size. We also investigate how the four types of interference competition impact the evolutionary dynamics and resultant diversity and trophic structure of size-structured communities. Like other types of trait-mediated competition, all four types of interference competition can induce disruptive selection and thus promote initial diversification. Even though foraging interference and reproductive interference are more potent in promoting initial diversification, they catalyze the formation of diverse communities with complex trophic structure only at high levels of interference intensity. By contrast, survival interference does so already at intermediate levels, while reproductive interference can only support relatively smaller communities with simpler trophic structure. Taken together, our results show how the type and intensity of interference competition jointly affect coexistence patterns in structured population models. Copyright © 2015 Elsevier Ltd. All rights reserved.
The Impact of Racism on the Sexual and Reproductive Health of African American Women
Prather, Cynthia; Fuller, Taleria R.; Marshall, Khiya J.; Jeffries, William L.
2016-01-01
African American women are disproportionately affected by multiple sexual and reproductive health conditions compared with women of other races/ethnicities. Research suggests that social determinants of health, including poverty, unemployment, and limited education, contribute to health disparities. However, racism is a probable underlying determinant of these social conditions. This article uses a socioecological model to describe racism and its impact on African American women’s sexual and reproductive health. Although similar models have been used for specific infectious and chronic diseases, they have not described how the historical underpinnings of racism affect current sexual and reproductive health outcomes among African American women. We propose a socioecological model that demonstrates how social determinants grounded in racism affect individual behaviors and interpersonal relationships, which may contribute to sexual and reproductive health outcomes. This model provides a perspective to understand how these unique contextual experiences are intertwined with the daily lived experiences of African American women and how they are potentially linked to poor sexual and reproductive health outcomes. The model also presents an opportunity to increase dialog and research among public health practitioners and encourages them to consider the role of these contextual experiences and supportive data when developing prevention interventions. Considerations address the provision of opportunities to promote health equity by reducing the effects of racism and improving African American women’s sexual and reproductive health. PMID:27227533
The Impact of Racism on the Sexual and Reproductive Health of African American Women.
Prather, Cynthia; Fuller, Taleria R; Marshall, Khiya J; Jeffries, William L
2016-07-01
African American women are disproportionately affected by multiple sexual and reproductive health conditions compared with women of other races/ethnicities. Research suggests that social determinants of health, including poverty, unemployment, and limited education, contribute to health disparities. However, racism is a probable underlying determinant of these social conditions. This article uses a socioecological model to describe racism and its impact on African American women's sexual and reproductive health. Although similar models have been used for specific infectious and chronic diseases, they have not described how the historical underpinnings of racism affect current sexual and reproductive health outcomes among African American women. We propose a socioecological model that demonstrates how social determinants grounded in racism affect individual behaviors and interpersonal relationships, which may contribute to sexual and reproductive health outcomes. This model provides a perspective to understand how these unique contextual experiences are intertwined with the daily lived experiences of African American women and how they are potentially linked to poor sexual and reproductive health outcomes. The model also presents an opportunity to increase dialog and research among public health practitioners and encourages them to consider the role of these contextual experiences and supportive data when developing prevention interventions. Considerations address the provision of opportunities to promote health equity by reducing the effects of racism and improving African American women's sexual and reproductive health.
Ovarian function's role during cancer cachexia progression in the female mouse.
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.
ARRAYS FOR BIOMONITORING ENVIRONMENTAL AND REPRODUCTIVE TOXICOLOGY
DNA arrays are receiving increasing interest as a tool for monitoring the developmental and reproductive impact of xenobiotics and other hazardous materials on human and wildlife populations. The primary tenet of toxicogenomics is that effects of environmental exposure on cellul...
No Evidence for a Trade-Off between Reproductive Investment and Immunity in a Rodent
Xu, Yan-Chao; Yang, Deng-Bao; Wang, De-Hua
2012-01-01
Life history theory assumes there are trade-offs between competing functions such as reproduction and immunity. Although well studied in birds, studies of the trade-offs between reproduction and immunity in small mammals are scarce. Here we examined whether reduced immunity is a consequence of reproductive effort in lactating Brandt's voles (Lasiopodomys brandtii). Specifically, we tested the effects of lactation on immune function (Experiment I). The results showed that food intake and resting metabolic rate (RMR) were higher in lactating voles (6≤ litter size ≤8) than that in non-reproductive voles. Contrary to our expectation, lactating voles also had higher levels of serum total Immunoglobulin G (IgG) and anti-keyhole limpet hemocyanin (KLH) IgG and no change in phytohemagglutinin (PHA) response and anti-KLH Immunoglobulin M (IgM) compared with non-reproductive voles, suggesting improved rather than reduced immune function. To further test the effect of differences in reproductive investment on immunity, we compared the responses between natural large (n≥8) and small litter size (n≤6) (Experiment II) and manipulated large (11–13) and small litter size (2–3) (Experiment III). During peak lactation, acquired immunity (PHA response, anti-KLH IgG and anti-KLH IgM) was not significantly different between voles raising large or small litters in both experiments, despite the measured difference in reproductive investment (greater litter size, litter mass, RMR and food intake in the voles raising larger litters). Total IgG was higher in voles with natural large litter size than those with natural small litter size, but decreased in the enlarged litter size group compared with control and reduced group. Our results showed that immune function is not suppressed to compensate the high energy demands during lactation in Brandt's voles and contrasting the situation in birds, is unlikely to be an important aspect mediating the trade-off between reproduction and survival. PMID:22649512
Davies, Scott; Gao, Sisi; Valle, Shelley; Bittner, Stephanie; Hutton, Pierce; Meddle, Simone L.; Deviche, Pierre
2015-01-01
ABSTRACT Energy deficiency can suppress reproductive function in vertebrates. As the orchestrator of reproductive function, endocrine activity of the hypothalamo-pituitary–gonadal (HPG) axis is potentially an important mechanism mediating such effects. Previous experiments in wild-caught birds found inconsistent relationships between energy deficiency and seasonal reproductive function, but these experiments focused on baseline HPG axis activity and none have investigated the responsiveness of this axis to endocrine stimulation. Here, we present data from an experiment in Abert's towhees, Melozone aberti, using gonadotropin-releasing hormone (GnRH) and luteinizing hormone (LH) challenges to investigate whether energy deficiency modulates the plasma testosterone responsiveness of the HPG axis. Wild-caught birds were either ad libitum fed or energetically constrained via chronic food restriction during photoinduced reproductive development. Energy deficiency did not significantly affect the development of reproductive morphology, the baseline endocrine activity of the HPG axis, or the plasma testosterone response to GnRH challenge. Energy deficiency did, however, decrease the plasma testosterone responsiveness to LH challenge. Collectively, these observations suggest that energy deficiency has direct gonadal effects consisting of a decreased responsiveness to LH stimulation. Our study, therefore, reveals a mechanism by which energy deficiency modulates reproductive function in wild birds in the absence of detectable effects on baseline HPG axis activity. PMID:26333925
Davies, Scott; Gao, Sisi; Valle, Shelley; Bittner, Stephanie; Hutton, Pierce; Meddle, Simone L; Deviche, Pierre
2015-07-10
Energy deficiency can suppress reproductive functions in vertebrates. As the orchestrator of reproductive function, endocrine activity of the hypothalamo-pituitary-gonadal (HPG) axis is potentially an important mechanism mediating such effects. Previous experiments in wild-caught birds found inconsistent relationships between energy deficiency and seasonal reproductive function, but these experiments focused on baseline HPG axis activity and none has investigated the responsiveness of this axis to endocrine stimulation. Here, we present data from an experiment in Abert's Towhees, Melozone aberti, using gonadotropin-releasing hormone (GnRH) and luteinizing hormone (LH) challenges to investigate whether energy deficiency modulates the plasma testosterone (T) responsiveness of the HPG axis. Wild-caught birds were either ad libitum-fed or energetically constrained via chronic food restriction during photoinduced reproductive development. Energy deficiency did not significantly affect the development of reproductive morphology, the baseline endocrine activity of the HPG axis, or the plasma T response to GnRH challenge. Energy deficiency did, however, decrease the plasma T responsiveness to LH challenge. Collectively, these observations suggest that energy deficiency has direct gonadal effects consisting in decreased responsiveness to LH stimulation. Our study, therefore, reveals a mechanism by which energy deficiency modulates reproductive function in wild birds in the absence of detectable effects on baseline HPG axis activity. © 2015. Published by The Company of Biologists Ltd.
Davies, Scott; Gao, Sisi; Valle, Shelley; Bittner, Stephanie; Hutton, Pierce; Meddle, Simone L; Deviche, Pierre
2015-09-01
Energy deficiency can suppress reproductive function in vertebrates. As the orchestrator of reproductive function, endocrine activity of the hypothalamo-pituitary-gonadal (HPG) axis is potentially an important mechanism mediating such effects. Previous experiments in wild-caught birds found inconsistent relationships between energy deficiency and seasonal reproductive function, but these experiments focused on baseline HPG axis activity and none have investigated the responsiveness of this axis to endocrine stimulation. Here, we present data from an experiment in Abert's towhees, Melozone aberti, using gonadotropin-releasing hormone (GnRH) and luteinizing hormone (LH) challenges to investigate whether energy deficiency modulates the plasma testosterone responsiveness of the HPG axis. Wild-caught birds were either ad libitum fed or energetically constrained via chronic food restriction during photoinduced reproductive development. Energy deficiency did not significantly affect the development of reproductive morphology, the baseline endocrine activity of the HPG axis, or the plasma testosterone response to GnRH challenge. Energy deficiency did, however, decrease the plasma testosterone responsiveness to LH challenge. Collectively, these observations suggest that energy deficiency has direct gonadal effects consisting of a decreased responsiveness to LH stimulation. Our study, therefore, reveals a mechanism by which energy deficiency modulates reproductive function in wild birds in the absence of detectable effects on baseline HPG axis activity. © 2015. Published by The Company of Biologists Ltd.
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...
Impact of 5'-amp-activated Protein Kinase on Male Gonad and Spermatozoa Functions.
Nguyen, Thi Mong Diep
2017-01-01
As we already know, the male reproductive system requires less energetic investment than the female one. Nevertheless, energy balance is an important feature for spermatozoa production in the testis and for spermatozoa properties after ejaculation. The 5'-AMP-activated protein kinase, AMPK, is a sensor of cell energy, that regulates many metabolic pathways and that has been recently shown to control spermatozoa quality and functions. It is indeed involved in the regulation of spermatozoa quality through its action on the proliferation of testicular somatic cells (Sertoli and Leydig), on spermatozoa motility and acrosome reaction. It also favors spermatozoa quality through the management of lipid peroxidation and antioxidant enzymes. I review here the most recent data available on the roles of AMPK in vertebrate spermatozoa functions.
Kekäläinen, Jukka; Pirhonen, Juhani; Taskinen, Jouni
2014-01-01
Parasites take their resources from hosts and thus directly reduce available resources for hosts’ own body functions, such as growth and reproduction. Furthermore, parasite infections cause significant indirect costs to their hosts in terms of increased investments on immune defense. In this study, we investigated the impact of parasite infection on the sperm quality and expression of secondary sexual ornamentation (saturation of the red abdominal colouration and number of breeding tubercles) in the Eurasian minnow (Phoxinus phoxinus). We exposed minnows to a high and low dose of common nonspecific fish ectoparasite, the glochidia larvae of duck mussel (Anodonta anatina) and tested whether parasite infection leads to trade-off in sperm quality and/or ornamental expression. We found that glochidia infection reduces the curvature of the sperm swimming trajectory, number of breeding tubercles, and possibly male competitive ability, but does not affect expression of male color ornamentation. Furthermore, glochidia infection was found to reduce sperm motility, but only when all the noninfected individuals were excluded from the model. Supporting one of the predictions by phenotype-linked fertility hypothesis both in high-infection and low-infection group male breeding colouration was positively associated with sperm quality. Our results suggest that although glochidia infection may have negative impact on male reproductive success, parasite-induced costs may not create strong trade-off between breeding colouration and sperm quality or that such trade-off become detectable only in resource-limited conditions. PMID:25540686
Embryotoxic cytokines-Potential roles in embryo loss and fetal programming.
Robertson, Sarah A; Chin, Peck-Yin; Femia, Joseph G; Brown, Hannah M
2018-02-01
Cytokines in the reproductive tract environment at conception mediate a dialogue between the embryo and maternal tissues to profoundly influence embryo development and implantation success. Through effects on gene expression and the cell stress response, cytokines elicit an epigenetic impact with consequences for placental development and fetal growth, which in turn affect metabolic phenotype and long-term health of offspring. There is substantial evidence demonstrating that pro-survival cytokines, such as GM-CSF, CSF1, LIF, HB-EGF and IGFII, support embryos to develop optimally. Less attention has been paid to cytokines that adversely impact embryo development, including the pro-inflammatory cytokines TNF, TRAIL and IFNG. These agents elicit cell stress, impair cell survival and retard blastocyst development, and at sufficiently high concentrations, can cause embryo demise. Experiments in mice suggest these so-called 'embryotoxic' cytokines can harm embryos through pro-apoptotic and adverse programming effects, as well as indirectly suppressing uterine receptivity through the maternal immune response. Embryotrophic factors may mitigate against and protect from these adverse effects. Thus, the balance between embryotrophic and embryotoxic cytokines can impart effects on embryo development and implantation, and has the potential to contribute to endometrial 'biosensor' function to mediate embryo selection. Embryotoxic cytokines can be elevated in plasma and reproductive tract tissues in inflammatory conditions including infection, diabetes, obesity, PCOS and endometriosis. Studies are therefore warranted to investigate whether excessive embryotoxic cytokines contribute to infertility and recurrent implantation failure in women, and compromised reproductive performance in livestock animals. Copyright © 2018 Elsevier B.V. All rights reserved.
EFFECTS OF SELENIUM ON MALLARD DUCK REPRODUCTION AND IMMUNE FUNCTION
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...
Reproductive Life Planning: Raising the Questions.
Morse, Jessica E; Moos, Merry-K
2018-04-01
Introduction Unintended pregnancy has been a concerning public health problem for decades. As we begin to understand the complexities of pregnancy intention and how women experience these pregnancies, reproductive life planning offers a paradigm shift. Methods Reproductive life planning is a patient-centered approach that places a patient's reproductive preferences-whether concrete or ambivalent-at the forefront of her clinical care. Results This process grants women and men the opportunity to consider how reproduction fits within the context of their broader lives. Within a clinical encounter, reproductive life planning allows counseling and care to be tailored to patient preferences. Discussion Although there is great potential for positive public health impacts in unintended pregnancy, contraceptive use and improved preconception health, the true benefit lies within reinforcing reproductive empowerment. Despite recommendations for universal adoption, many questions remain regarding implementation, equity and outcomes.
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.
Vaginal and uterine bacterial communities in postpartum lactating cows
USDA-ARS?s Scientific Manuscript database
Reproductive inefficiency in cattle has major impacts on overall productivity of beef and dairy operations, increasing the environmental footprint of these industries and thereby reducing sustainability. Decreased reproductive success and associated disease states have been correlated with the prese...
Base Structure Annex to Manpower Requirements Report for FY 1980
1979-01-01
Printing and Reproduction Installation Safety Installation Engineering Service Related Investment"* Support Groups/Units assigned to these functions...c 04 o1 fn n a K~~~2 W U4u~ S -Ct ’- .dc w u .S . . . ...... - . ..l .. .AF) . ... .. . z -, IVf ’ N 1 j C0 ---- -K dl fl~ t. I . .Wz x A jt vd idz "oz...actions must beanalyzed to determine if any of the activities associated with the action will cause a significuant impact on the human environ-ment or
Perfus-Barbeoch, Laetitia; Da Rocha, Martine; Sallet, Erika; Bailly-Bechet, Marc; Castagnone-Sereno, Philippe; Flot, Jean-François; Kozlowski, Djampa K.; Cazareth, Julie; Couloux, Arnaud; Da Silva, Corinne; Guy, Julie; Kim-Jo, Yu-Jin; Rancurel, Corinne; Abad, Pierre; Wincker, Patrick
2017-01-01
Root-knot nematodes (genus Meloidogyne) exhibit a diversity of reproductive modes ranging from obligatory sexual to fully asexual reproduction. Intriguingly, the most widespread and devastating species to global agriculture are those that reproduce asexually, without meiosis. To disentangle this surprising parasitic success despite the absence of sex and genetic exchanges, we have sequenced and assembled the genomes of three obligatory ameiotic and asexual Meloidogyne. We have compared them to those of relatives able to perform meiosis and sexual reproduction. We show that the genomes of ameiotic asexual Meloidogyne are large, polyploid and made of duplicated regions with a high within-species average nucleotide divergence of ~8%. Phylogenomic analysis of the genes present in these duplicated regions suggests that they originated from multiple hybridization events and are thus homoeologs. We found that up to 22% of homoeologous gene pairs were under positive selection and these genes covered a wide spectrum of predicted functional categories. To biologically assess functional divergence, we compared expression patterns of homoeologous gene pairs across developmental life stages using an RNAseq approach in the most economically important asexually-reproducing nematode. We showed that >60% of homoeologous gene pairs display diverged expression patterns. These results suggest a substantial functional impact of the genome structure. Contrasting with high within-species nuclear genome divergence, mitochondrial genome divergence between the three ameiotic asexuals was very low, signifying that these putative hybrids share a recent common maternal ancestor. Transposable elements (TE) cover a ~1.7 times higher proportion of the genomes of the ameiotic asexual Meloidogyne compared to the sexual relative and might also participate in their plasticity. The intriguing parasitic success of asexually-reproducing Meloidogyne species could be partly explained by their TE-rich composite genomes, resulting from allopolyploidization events, and promoting plasticity and functional divergence between gene copies in the absence of sex and meiosis. PMID:28594822
Discrete two-sex models of population dynamics: On modelling the mating function
NASA Astrophysics Data System (ADS)
Bessa-Gomes, Carmen; Legendre, Stéphane; Clobert, Jean
2010-09-01
Although sexual reproduction has long been a central subject of theoretical ecology, until recently its consequences for population dynamics were largely overlooked. This is now changing, and many studies have addressed this issue, showing that when the mating system is taken into account, the population dynamics depends on the relative abundance of males and females, and is non-linear. Moreover, sexual reproduction increases the extinction risk, namely due to the Allee effect. Nevertheless, different studies have identified diverse potential consequences, depending on the choice of mating function. In this study, we investigate the consequences of three alternative mating functions that are frequently used in discrete population models: the minimum; the harmonic mean; and the modified harmonic mean. We consider their consequences at three levels: on the probability that females will breed; on the presence and intensity of the Allee effect; and on the extinction risk. When we consider the harmonic mean, the number of times the individuals of the least abundant sex mate exceeds their mating potential, which implies that with variable sex-ratios the potential reproductive rate is no longer under the modeller's control. Consequently, the female breeding probability exceeds 1 whenever the sex-ratio is male-biased, which constitutes an obvious problem. The use of the harmonic mean is thus only justified if we think that this parameter should be re-defined in order to represent the females' breeding rate and the fact that females may reproduce more than once per breeding season. This phenomenon buffers the Allee effect, and reduces the extinction risk. However, when we consider birth-pulse populations, such a phenomenon is implausible because the number of times females can reproduce per birth season is limited. In general, the minimum or modified harmonic mean mating functions seem to be more suitable for assessing the impact of mating systems on population dynamics.
Daly, Jonathan; Gunn, Ian; Kirby, Nick; Jones, Robert; Galloway, David
2007-09-01
Serial ultrasound examination of four mature female sevengill sharks (Notorynchus cepedianus) was carried out over 18 months. Monitoring the reproductive cycle and development of follicles and fetuses in sharks in a noninvasive manner using this technique has not been reported previously. Sharks were caught out of the "Oceanarium" tank by divers using a specially made catch-out bag, and brought to a holding area for examination. A behavior scoring system was used to monitor the impact of regular handling on the well-being of the animals. Ultrasound showed the growth and regression of follicles in sevengill ovaries, and allowed an approximation of the reproductive stage of these sharks. Monitoring behavior at five time points during the procedure showed that regular handling of sharks for clinical studies could be done with minimal impact on animal welfare. The ability to follow reproductive events in elasmobranches using ultrasonography is an important step in the application of assisted reproductive technology in these species. Assisted reproductive technology, such as monitoring female reproductive cycles and artificial insemination, could potentially be used to maintain genetic diversity and compliment aquaria-based breeding programs for endangered species such as the gray nurse shark (Carcharias taurus). Zoo Biol 26:383-395, 2007. (c) 2007 Wiley-Liss, Inc.
Health costs of reproduction are minimal despite high fertility, mortality and subsistence lifestyle
Gurven, Michael; Costa, Megan; Ben Trumble; Stieglitz, Jonathan; Beheim, Bret; Eid Rodriguez, Daniel; Hooper, Paul L.; Kaplan, Hillard
2016-01-01
Women exhibit greater morbidity than men despite higher life expectancy. An evolutionary life history framework predicts that energy invested in reproduction trades-off against investments in maintenance and survival. Direct costs of reproduction may therefore contribute to higher morbidity, especially for women given their greater direct energetic contributions to reproduction. We explore multiple indicators of somatic condition among Tsimane forager-horticulturalist women (Total Fertility Rate = 9.1; n = 592 aged 15–44 years, n = 277 aged 45+). We test whether cumulative live births and the pace of reproduction are associated with nutritional status and immune function using longitudinal data spanning 10 years. Higher parity and faster reproductive pace are associated with lower nutritional status (indicated by weight, body mass index, body fat) in a cross-section, but longitudinal analyses show improvements in women’s nutritional status with age. Biomarkers of immune function and anemia vary little with parity or pace of reproduction. Our findings demonstrate that even under energy-limited and infectious conditions, women are buffered from the potential depleting effects of rapid reproduction and compound offspring dependency characteristic of human life histories. PMID:27436412
The role of the leptin in reproduction.
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.
Metabolic influences on neuroendocrine regulation of reproduction.
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.
Quinteros, Fernanda A; Poliandri, Ariel H B; Machiavelli, Leticia I; Cabilla, Jimena P; Duvilanski, Beatriz H
2007-01-01
Hexavalent chromium (Cr VI) is a highly toxic metal and an environmental pollutant. Different studies indicate that Cr VI exposure adversely affects reproductive functions. This metal has been shown to affect several tissues and organs but Cr VI effects on pituitary gland have not been reported. Anterior pituitary hormones are central for the body homeostasis and have a fundamental role in reproductive physiology. The aim of this study was to evaluate the effect of Cr VI at the pituitary level both in vivo and in vitro. We showed that Cr VI accumulates in the pituitary and hypothalamus, and decreases serum prolactin levels in vivo but observed no effects on LH levels. In anterior pituitary cells in culture, the effect of Cr VI on hormone secretion followed the same differential pattern. Besides, lactotrophs were more sensitive to the toxicity of the metal. As a result of oxidative stress generation, Cr VI induced apoptosis evidenced by nuclear fragmentation and caspase 3 activation. Our results indicate that the anterior pituitary gland can be a target of Cr VI toxicity in vivo and in vitro, thus producing a negative impact on the hypothalamic-pituitary-gonadal axis and affecting the normal endocrine function.
Kisspeptin modulates sexual and emotional brain processing in humans.
Comninos, Alexander N; Wall, Matthew B; Demetriou, Lysia; Shah, Amar J; Clarke, Sophie A; Narayanaswamy, Shakunthala; Nesbitt, Alexander; Izzi-Engbeaya, Chioma; Prague, Julia K; Abbara, Ali; Ratnasabapathy, Risheka; Salem, Victoria; Nijher, Gurjinder M; Jayasena, Channa N; Tanner, Mark; Bassett, Paul; Mehta, Amrish; Rabiner, Eugenii A; Hönigsperger, Christoph; Silva, Meire Ribeiro; Brandtzaeg, Ole Kristian; Lundanes, Elsa; Wilson, Steven Ray; Brown, Rachel C; Thomas, Sarah A; Bloom, Stephen R; Dhillo, Waljit S
2017-02-01
Sex, emotion, and reproduction are fundamental and tightly entwined aspects of human behavior. At a population level in humans, both the desire for sexual stimulation and the desire to bond with a partner are important precursors to reproduction. However, the relationships between these processes are incompletely understood. The limbic brain system has key roles in sexual and emotional behaviors, and is a likely candidate system for the integration of behavior with the hormonal reproductive axis. We investigated the effects of kisspeptin, a recently identified key reproductive hormone, on limbic brain activity and behavior. Using a combination of functional neuroimaging and hormonal and psychometric analyses, we compared the effects of kisspeptin versus vehicle administration in 29 healthy heterosexual young men. We demonstrated that kisspeptin administration enhanced limbic brain activity specifically in response to sexual and couple-bonding stimuli. Furthermore, kisspeptin's enhancement of limbic brain structures correlated with psychometric measures of reward, drive, mood, and sexual aversion, providing functional significance. In addition, kisspeptin administration attenuated negative mood. Collectively, our data provide evidence of an undescribed role for kisspeptin in integrating sexual and emotional brain processing with reproduction in humans. These results have important implications for our understanding of reproductive biology and are highly relevant to the current pharmacological development of kisspeptin as a potential therapeutic agent for patients with common disorders of reproductive function. National Institute for Health Research (NIHR), Wellcome Trust (Ref 080268), and the Medical Research Council (MRC).
Di Renzo, Gian Carlo; Conry, Jeanne A; Blake, Jennifer; DeFrancesco, Mark S; DeNicola, Nathaniel; Martin, James N; McCue, Kelly A; Richmond, David; Shah, Abid; Sutton, Patrice; Woodruff, Tracey J; van der Poel, Sheryl Ziemin; Giudice, Linda C
2015-12-01
Exposure to toxic environmental chemicals during pregnancy and breastfeeding is ubiquitous and is a threat to healthy human reproduction. There are tens of thousands of chemicals in global commerce, and even small exposures to toxic chemicals during pregnancy can trigger adverse health consequences. Exposure to toxic environmental chemicals and related health outcomes are inequitably distributed within and between countries; universally, the consequences of exposure are disproportionately borne by people with low incomes. Discrimination, other social factors, economic factors, and occupation impact risk of exposure and harm. Documented links between prenatal exposure to environmental chemicals and adverse health outcomes span the life course and include impacts on fertility and pregnancy, neurodevelopment, and cancer. The global health and economic burden related to toxic environmental chemicals is in excess of millions of deaths and billions of dollars every year. On the basis of accumulating robust evidence of exposures and adverse health impacts related to toxic environmental chemicals, the International Federation of Gynecology and Obstetrics (FIGO) joins other leading reproductive health professional societies in calling for timely action to prevent harm. FIGO recommends that reproductive and other health professionals advocate for policies to prevent exposure to toxic environmental chemicals, work to ensure a healthy food system for all, make environmental health part of health care, and champion environmental justice. Copyright © 2015 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.
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.
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
Impacts of climate change and environmental factors on reproduction and development in wildlife
Milligan, Stuart R.; Holt, William V.; Lloyd, Rhiannon
2009-01-01
The robustness of the growth of the human population in the face of environmental impacts is in contrast to the sensitivity of wildlife. There is a danger that the success of reproduction of humans provides a false sense of security for the public, media and politicians with respect to wildlife survival, the maintenance of viable ecosystems and the capacity for recovery of damaged ecosystems and endangered species. In reality, the success of humans to populate the planet has been dependent on the combination of the ability to reproduce successfully and to minimize loss of offspring through controlling and manipulating their own micro-environment. In contrast, reproduction in wildlife is threatened by environmental changes operating at many different physiological levels. PMID:19833643
Ovarian function’s role during cancer cachexia progression in the female mouse
Hetzler, Kimbell L.; Hardee, Justin P.; LaVoie, Holly A.; Murphy, E. Angela
2017-01-01
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 ApcMin/+ 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 ApcMin/+ mouse. Our study of ovarian reproductive function in female ApcMin/+ 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 ApcMin/+ mice. PMID:28292759
Wittemyer, George; Ganswindt, André; Hodges, Keith
2007-03-01
Non-invasive endocrine methods enable investigation of the relationship between ecological variation and ovarian activity and how this impacts on demographic processes. The underlying physiological factors driving high variation in inter-calving intervals among multi-parous African elephants offer an interesting system for such an investigation. This study investigates the relationship between Normalized Differential Vegetation Index (NDVI), an ecosystem surrogate measure of primary productivity, and fecal progestin concentrations among wild female elephants. Matched fecal samples and behavioral data on reproductive activity were collected from 37 focal individuals during the two-year study. Linear mixed models were used to explore the relationship between fecal 5alpha-pregnane-3-ol-20-one concentrations and the independent variables of NDVI, calf sex, female age, gestation day, and time since last parturition. Among both non-pregnant and pregnant females, fecal 5alpha-pregnane-3-ol-20-one concentrations were significantly correlated with time-specific NDVI indicating a strong relationship between ecological conditions and endocrine activity regulating reproduction. In addition, the age of a female and time since her last parturition impacted hormone concentrations. These results indicate that the identification of an individual's reproductive status from a single hormone sample is possible, but difficult to achieve in practice since numerous independent factors, particularly season, impact fecal hormone concentrations. Regardless of season, however, fecal 5alpha-pregnane-3-ol-20-one concentrations below 1 microg/g were exclusively collected from non-pregnant females, which could be used as a threshold value to identify non-pregnant individuals. Collectively the information generated contributes to a better understanding of environmental regulation of reproductive endocrinology in wild elephant populations, information salient to the management and manipulation of population dynamics in this species.
[The impact of the social economic conditions on the reproduction processes].
Leonova, N G
2007-01-01
The social economic conditions of population reproduction in the Trans-Dniester Region with the emphasis on its specifics are analyzed. The natural dynamics of population is estimated including gender and age peculiarities, marriage and divorces statistics, migration processes and population health in the region. It is shown that the population reproduction dynamics follows the natural laws and processes. The role of the post-Soviet period social economic conditions harmful to health are considered. The interdependencies between the social economic development and population reproduction are revealed. The recommendations related to the means of the further enhancement of social economic conditions as related to population reproduction in the Trans-Dniester Region are proposed.
77 FR 65913 - Privacy Act of 1974: Systems of Records.
Federal Register 2010, 2011, 2012, 2013, 2014
2012-10-31
... performing clerical, stenographic, or data analysis functions, or by reproduction of records by electronic or... performing clerical, stenographic, or data analysis functions, or by reproduction of records by electronic or... Services (OGIS) National Archives and Records Administration, in connection with mediation of FOIA requests...
Gobush, K S; Mutayoba, B M; Wasser, S K
2008-12-01
Widespread poaching prior to the 1989 ivory ban greatly altered the demographic structure of matrilineal African elephant (Loxodonta africana) family groups in many populations by decreasing the number of old, adult females. We assessed the long-term impacts of poaching by investigating genetic, physiological, and reproductive correlates of a disturbed social structure resulting from heavy poaching of an African elephant population in Mikumi National Park, Tanzania, prior to 1989. We examined fecal glucocorticoid levels and reproductive output among 218 adult female elephants from 109 groups differing in size, age structure, and average genetic relatedness over 25 months from 2003 to 2005. The distribution in group size has changed little since 1989, but the number of families with tusked old matriarchs has increased by 14.2%. Females from groups that lacked an old matriarch, first-order adult relatives, and strong social bonds had significantly higher fecal glucocorticoid values than those from groups with these features (all females R(2)= 0.31; females in multiadult groups R(2)= 0.46). Females that frequented isolated areas with historically high poaching risk had higher fecal glucocorticoid values than those in low poaching risk areas. Females with weak bonds and low group relatedness had significantly lower reproductive output (R(2)[U]=0.21). Females from disrupted groups, defined as having observed average group relatedness 1 SD below the expected mean for a simulated unpoached family, had significantly lower reproductive output than females from intact groups, despite many being in their reproductive prime. These results suggest that long-term negative impacts from poaching of old, related matriarchs have persisted among adult female elephants 1.5 decades after the 1989 ivory ban was implemented.
Balise, Victoria D; Meng, Chun-Xia; Cornelius-Green, Jennifer N; Kassotis, Christopher D; Kennedy, Rana; Nagel, Susan C
2016-09-15
This systematic review identified 45 original published research articles related to oil and gas extraction activities and human reproductive endpoints. Reproductive outcomes were categorized as [1] birth outcomes associated with maternal exposure, [2] semen quality, fertility, and birth outcomes associated with adult paternal exposure, [3] reproductive cancers, and [4] disruption of human sex steroid hormone receptors. The results indicate there is moderate evidence for an increased risk of preterm birth, miscarriage, birth defects, decreased semen quality, and prostate cancer. The quality of the evidence is low and/or inadequate for stillbirth, sex ratio, and birth outcomes associated with paternal exposure, and testicular cancer, female reproductive tract cancers, and breast cancer, and the evidence is inconsistent for an increased risk of low birth weight; therefore, no conclusions can be drawn for these health effects. There is ample evidence for disruption of the estrogen, androgen, and progesterone receptors by oil and gas chemicals, which provides a mechanistic rationale for how exposure to oil and gas activities may increase the health risks we have outlined. The results from this systematic review suggest there is a negative impact on human reproduction from exposure to oil and gas activities. Many of the 45 studies reviewed identified potential human health effects. Most of these studies focused on conventional oil and gas activities. Few studies have been conducted to evaluate the impact of unconventional oil and gas operations on human health. The impact of unconventional oil and gas activities may be greater than that of conventional activity, given that unconventional activities employ many of the same approaches and use dozens of known endocrine-disrupting chemicals in hydraulic fracturing. Copyright © 2016. Published by Elsevier Inc.
Duplouy, Anne; Woestmann, Luisa; Gallego Zamorano, Juan; Saastamoinen, Marjo
2018-04-01
In butterflies, male reproductive success is highly related to the quality and the size of the spermatophore transferred to the female. The spermatophore is a capsule produced by the male during copulation, which in many species contains sperm in addition to a nuptial gift, and which is digested by the female after copulation. The nuptial gift may contribute to egg production and offspring quality, and in some cases also to female body maintenance. The production of the spermatophore, however, represents a cost for the male and, in polyandrous species, ejaculates are sometimes allocated adaptively across matings. Nonetheless, although the ecological factors affecting the reproductive success of female butterflies have been the topic of numerous studies, little information exists on the factors affecting males' contribution to reproduction, and the indirect impacts on female fecundity and fitness. We used the Glanville fritillary butterfly, Melitaea cinxia (Linnaeus, 1758) (Nymphalidae), in order to assess variation in male allocation to matings. In this species, smaller males produce smaller spermatophores, but variation in spermatophore size is not correlated with female reproductive success. We show that spermatophore size increases with male age at first mating, decreases with mating frequency and adult food-deprivation, and is not influenced by developmental food-limitation. The length of copulation period does not influence the spermatophore size nor influences the polyandrous mating behavior in this species. Male contribution to his spermatophore size is clearly influenced by his condition and adult-resource at the time of mating. Despite this variation, spermatophore size does not seem to have a direct impact on female reproductive output or mating behavior. © 2016 The Authors Insect Science published by Wiley Publishing Asia Pty Ltd on behalf of Institute of Zoology, Chinese Academy of Sciences.
Tollington, Simon; Greenwood, Andrew; Jones, Carl G; Hoeck, Paquita; Chowrimootoo, Aurélie; Smith, Donal; Richards, Heather; Tatayah, Vikash; Groombridge, Jim J
2015-07-01
Infectious diseases are widely recognized to have substantial impact on wildlife populations. These impacts are sometimes exacerbated in small endangered populations, and therefore, the success of conservation reintroductions to aid the recovery of such species can be seriously threatened by outbreaks of infectious disease. Intensive management strategies associated with conservation reintroductions can further compound these negative effects in such populations. Exploring the sublethal effects of disease outbreaks among natural populations is challenging and requires longitudinal, individual life-history data on patterns of reproductive success and other indicators of individual fitness. Long-term monitoring data concerning detailed reproductive information of the reintroduced Mauritius parakeet (Psittacula echo) population collected before, during and after a disease outbreak was investigated. Deleterious effects of an outbreak of beak and feather disease virus (BFDV) were revealed on hatch success, but these effects were remarkably short-lived and disproportionately associated with breeding pairs which took supplemental food. Individual BFDV infection status was not predicted by any genetic, environmental or conservation management factors and was not associated with any of our measures of immune function, perhaps suggesting immunological impairment. Experimental immunostimulation using the PHA (phytohaemagglutinin assay) challenge technique did, however, provoke a significant cellular immune response. We illustrate the resilience of this bottlenecked and once critically endangered, island-endemic species to an epidemic outbreak of BFDV and highlight the value of systematic monitoring in revealing inconspicuous but nonetheless substantial ecological interactions. Our study demonstrates that the emergence of such an infectious disease in a population ordinarily associated with increased susceptibility does not necessarily lead to deleterious impacts on population growth and that negative effects on reproductive fitness can be short-lived. © 2015 The Authors. Journal of Animal Ecology published by John Wiley & Sons Ltd on behalf of British Ecological Society.
[The function of ERα in male reproductive system].
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.
Heifetz, Yael; Lindner, Moshe; Garini, Yuval; Wolfner, Mariana F
2014-03-31
Upon mating, regions of the female reproductive tract mature and alter their function [1-3], for example to facilitate storage of sperm or control the release of eggs [4-6]. The female's nervous system and neuromodulators play important roles in her responses to mating [7-13]. However, it is difficult to reconcile the reproductive tract's many changing but coordinated events with the small set of neuromodulators present [14-18]. We hypothesized that each part of the reproductive tract contains a characteristic combination of neuromodulators that confer unique identities on each region and that postmating changes in these combinations coordinate subsequent actions. We examined the presence, locations, and levels of neuromodulators and related molecules ("signaling molecules") in the reproductive tract of Drosophila melanogaster females before and after mating: the biogenic amine octopamine, which regulates ovulation rate in Drosophila and locusts [7, 14-20]; serotonin, which regulates muscle contraction in locust oviducts [21]; and the FMRF amide dromyosuppressin, which regulates contraction of Drosophila heart muscle [22] and may regulate muscle contractions in the reproductive tract, if it is expressed there. We find that separate aspects of mating (sperm, seminal proteins, and physical effects) independently modulate the release of signaling molecules. Each reproductive tract subregion displays a characteristic combination of signaling molecule release, resulting in a unique functional identity. These patterns, and thus functions, change reproducibly after mating. Thus, one event (mating) promotes new combinations of signaling molecules that endow different parts of the reproductive tract with unique temporal and spatial identities that facilitate many aspects of fertilization. Copyright © 2014 Elsevier Ltd. All rights reserved.
Lübke, Katrin T; Pause, Bettina M
2015-02-01
This article is part of a Special Issue "Chemosignals and Reproduction" Across phyla, chemosensory communication is crucial for mediating a variety of social behaviors, which form the basis for ontogenetic and phylogenetic survival. In the present paper, evidence on chemosensory communication in humans, with special reference to reproduction and survival, will be presented. First, the impact of chemosignals on human reproduction will be reviewed. Work will be presented, showing how chemosensory signals are involved in mate choice and partnership formation by communicating attractiveness and facilitating a partner selection, which is of evolutionary advantage, and furthermore providing information about the level of sexual hormones. In addition to direct effects on phylogenetic survival, chemosignals indirectly aid reproductive success by fostering harm protection. Results will be presented, showing that chemosensory communication aids the emotional bond between mother and child, which in turn motivates parental caretaking and protection, leading to infant survival. Moreover, the likelihood of group survival can be increased through the use of stress-related chemosignals. Stress-related chemosignals induce a stress-related physiology in the perceiver, thereby priming a fight-flight-response, which is necessary for an optimum adaption to environmental harm. Finally, effects of sexual orientation on chemosensory communication will be discussed in terms of their putative role in stabilizing social groups, which might indirectly provide harm protection and foster survival. An integrative model of the presented data will be introduced. In conclusion, an outlook, focusing on the involvement of chemosensory communication in human social behavior and illustrating a novel approach to the significance of chemosensory signals in human survival, will be given. Copyright © 2014 Elsevier Inc. All rights reserved.
Female reproductive cycles of wild female felids.
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.
Health issues in the Arab American community. Male infertility in Lebanon: a case-controlled study.
Kobeissi, Loulou; Inhorn, Marcia C
2007-01-01
The impact of risk factors, such as consanguinity and familial clustering, reproductive infections, traumas, and diseases, lifestyle factors and occupational and war exposures on male infertility, was investigated in a case-controlled study conducted in Lebanon. One-hundred-twenty males and 100 controls of Lebanese, Syrian or Lebanese-Palestinian descents were selected from two in-vitro fertilization (IVF) clinics located in Beirut, Lebanon. All cases suffered from impaired sperm count and function, according to World Health Organization guidelines for semen analysis. Controls were the fertile husbands of infertile women. Data were collected using a semi-structured interview, laboratory blood testing and the results of the most recent semen analysis. Univariate, bivariate and multivariate logistic regression analyses were used for data analysis, along with checks for effect modification and control of confounders. Consanguinity and the familial clustering of male infertility cases, as well as reproductive illnesses and war exposures were independently significant risk factors for male infertility. The odds of having infertility problems in the immediate family were 2.6 times higher in cases than controls. The odds of reproductive illness were 2 times higher in cases than controls. The odds of war exposures were 1.57 times higher in cases than controls. Occupational exposures, such as smoking and caffeine intake, were not shown to be important risk factors. This case-controlled study highlights the importance of investigating the etiology of male infertility in Middle Eastern communities. It suggests the need to expand research on male reproductive health in the Middle East in order to improve the prevention and management of male infertility and other male reproductive health problems.
NASA Astrophysics Data System (ADS)
Sepehrimanesh, Masood; Saeb, Mehdi; Nazifi, Saeed; Kazemipour, Nasrin; Jelodar, Gholamali; Saeb, Saeedeh
2014-09-01
This work analyzes the effects of radiofrequency-electromagnetic field (RF-EMF) exposure on the reproductive system of male rats, assessed by measuring circulating levels of FSH, LH, inhibin B, activin B, prolactin, and testosterone. Twenty adult male Sprague-Dawley rats (180 ± 10 g) were exposed to 900 MHz RF-EMF in four equal separated groups. The duration of exposure was 1, 2, and 4 h/day over a period of 30 days and sham-exposed animals were kept under the same environmental conditions as the exposed group except with no RF-EMF exposure. Before the exposure, at 15 and 30 days of exposure, determination of the abovementioned hormone levels was performed using ELISA. At the end of the experiment, FSH and LH values of the long time exposure (LTE) group were significantly higher than the sham-exposed group ( p < 0.05). Serum activin B and prolactin in the LTE group showed significant increase and inhibin B showed significant decrease than sham and short time exposed (STE) groups after 30 days RF-EMF exposure ( p < 0.05). Also, a significant decrease in serum testosterone levels in the LTE group was found compared to short and moderate time exposed (MTE) groups after 30 days RF-EMF exposure ( p < 0.05). Results suggest that reproductive hormone levels are disturbed as a result of RF-EMF exposure and it may possibly affect reproductive functions. However, testosterone and inhibin B concentrations as a fertility marker and spermatogenesis were decreased significantly.
Oxidative stress and its implications in female infertility - a clinician's perspective.
Agarwal, Ashok; Gupta, Sajal; Sharma, Rakesh
2005-11-01
Reactive oxygen species (ROS) have a role in the modulation of gamete quality and gamete interaction. Generation of ROS is inherent in spermatozoa and contaminating leukocytes. ROS influence spermatozoa, oocytes, embryos and their environment. Oxidative stress (OS) mediates peroxidative damage to the sperm membrane and induces nuclear DNA damage. ROS can modulate the fertilizing capabilities of the spermatozoa. There is extensive literature on OS and its role in male infertility and sperm DNA damage and its effects on assisted reproductive techniques. Evidence is accumulating on the role of ROS in female reproduction. Many animal and human studies have elucidated a role for ROS in oocyte development, maturation, follicular atresia, corpus luteum function and luteolysis. OS-mediated precipitation of pathologies in the female reproductive tract is similar to those involved in male infertility. OS influences the oocyte and embryo quality and thus the fertilization rates. ROS appears to play a significant role in the modulation of gamete interaction and also for successful fertilization to take place. ROS in culture media may impact post-fertilization development, i.e. cleavage rate, blastocyst yield and quality (indicators of assisted reproduction outcomes). OS is reported to affect both natural and assisted fertility. Antioxidant strategies should be able to intercept both extracellular and intracellular ROS. This review discusses the sources of ROS in media used in IVF-embryo transfer and strategies to overcome OS in oocyte in-vitro maturation, in-vitro culture and sperm preparation techniques.
Baxi, Kunal; Ghavidel, Ata; Waddell, Brandon; Harkness, Troy A; de Carvalho, Carlos E
2017-09-01
Aging in eukaryotes is accompanied by widespread deterioration of the somatic tissue. Yet, abolishing germ cells delays the age-dependent somatic decline in Caenorhabditis elegans In adult worms lacking germ cells, the activation of the DAF-9/DAF-12 steroid signaling pathway in the gonad recruits DAF-16 activity in the intestine to promote longevity-associated phenotypes. However, the impact of this pathway on the fitness of normally reproducing animals is less clear. Here, we explore the link between progeny production and somatic aging and identify the loss of lysosomal acidity-a critical regulator of the proteolytic output of these organelles-as a novel biomarker of aging in C. elegans The increase in lysosomal pH in older worms is not a passive consequence of aging, but instead is timed with the cessation of reproduction, and correlates with the reduction in proteostasis in early adult life. Our results further implicate the steroid signaling pathway and DAF-16 in dynamically regulating lysosomal pH in the intestine of wild-type worms in response to the reproductive cycle. In the intestine of reproducing worms, DAF-16 promotes acidic lysosomes by upregulating the expression of v-ATPase genes. These findings support a model in which protein clearance in the soma is linked to reproduction in the gonad via the active regulation of lysosomal acidification. Copyright © 2017 by the Genetics Society of America.
Deng, Xiaobao; Mohandass, Dharmalingam; Katabuchi, Masatoshi; Hughes, Alice C.; Roubik, David W.
2015-01-01
Nectar-robbing has the potential to strongly affect male and female reproductive fitness of plants. One example of nectar theft is that shown by striped-squirrels (Tamiops swinhoei) on a number of ginger species, including Alpinia roxburghii and A. kwangsiensis (Zingiberaceae). In this study, we used a fluorescent dye as a pollen analogue, and measured fruit and seed output, to test the effect of squirrel nectar-robbing on A. roxburghii reproductive fitness. Pollen transfer between robbed and unrobbed flowers was assessed by comparing 60 randomly established plots containing robbed and unrobbed flowers. The frequency of squirrel robbing visits and broken styles were recorded from a number of flowers for five consecutive days. Two bee species (Bombus eximius and Apis cerana), were the primary pollinators, and their visitation frequency was recorded for six consecutive days. The results showed that fluorescent powder from unrobbed flowers was dispersed further, and to a greater number of flowers than that placed on robbed flowers. Additionally, robbing flowers caused significant damage to reproductive organs, resulting in lower fruit and seed sets in robbed than in unrobbed flowers and influencing both male and female fitness. The frequency of the primary pollinator visits (B. eximius) was significantly higher for unrobbed plants than for robbed plants. The present study clearly shows the negative impact of squirrel robbing on A. roxburghii male reproductive fitness and neutral impact on female reproductive fitness. PMID:26689684
Long-Term Effects of Environmental Endocrine Disruptors on Reproductive Physiology and Behavior
Patisaul, Heather B.; Adewale, Heather B.
2009-01-01
It is well established that, over the course of development, hormones shape the vertebrate brain such that sex specific physiology and behaviors emerge. Much of this occurs in discrete developmental windows that span gestation through the prenatal period, although it is now becoming clear that at least some of this process continues through puberty. Perturbation of this developmental progression can permanently alter the capacity for reproductive success. Wildlife studies have revealed that exposure to endocrine disrupting compounds (EDCs), either naturally occurring or man made, can profoundly alter reproductive physiology and ultimately impact entire populations. Laboratory studies in rodents and other species have elucidated some of the mechanisms by which this occurs and strongly indicate that humans are also vulnerable to disruption. Use of hormonally active compounds in human medicine has also unfortunately revealed that the developing fetus can be exposed to and affected by endocrine disruptors, and that it might take decades for adverse effects to manifest. Research within the field of environmental endocrine disruption has also contributed to the general understanding of how early life experiences can alter reproductive physiology and behavior through non-genomic, epigenetic mechanisms such as DNA methylation and histone acetylation. These types of effects have the potential to impact future generations if the germ line is affected. This review provides an overview of how exposure to EDCs, particularly those that interfere with estrogen action, impacts reproductive physiology and behaviors in vertebrates. PMID:19587848
Sexual function in infertile women with polycystic ovary syndrome and unexplained infertility.
Diamond, Michael P; Legro, Richard S; Coutifaris, Christos; Alvero, Ruben; Robinson, Randal D; Casson, Peter A; Christman, Gregory M; Huang, Hao; Hansen, Karl R; Baker, Valerie; Usadi, Rebecca; Seungdamrong, Aimee; Bates, G Wright; Rosen, R Mitchell; Schlaff, William; Haisenleder, Daniel; Krawetz, Stephen A; Barnhart, Kurt; Trussell, J C; Santoro, Nanette; Eisenberg, Esther; Zhang, Heping
2017-08-01
While female sexual dysfunction is a frequent occurrence, characteristics in infertile women are not well delineated. Furthermore, the impact of infertility etiology on the characteristics in women with differing androgen levels observed in women with polycystic ovary syndrome and unexplained infertility has not been assessed. The objective of the study was to determine the characteristics of sexual dysfunction in women with polycystic ovary syndrome and unexplained infertility. A secondary data analysis was performed on 2 of Eunice Kennedy Shriver National Institute of Child Health and Human Development Cooperative Reproductive Medicine Networks clinical trials: Pregnancy in Polycystic Ovary Syndrome Study II and Assessment of Multiple Intrauterine Gestations From Ovarian Stimulation. Both protocols assessed female sexual function using the Female Sexual Function Inventory and the Female Sexual Distress Scale. Women with polycystic ovary syndrome had higher weight and body mass index than women with unexplained infertility (each P < .001), greater phenotypic (Ferriman-Gallwey hirsutism score, sebum score, and acne score; each P < .001), and hormonal (testosterone, free testosterone, and dehydroepiandrosterone; each P < .001) evidence of androgen excess. Sexual function scores, as assessed by the Female Sexual Function Inventory, were nearly identical. The Female Sexual Distress Scale total score was higher in women with polycystic ovary syndrome. The mean Female Sexual Function Inventory total score increased slightly as the free androgen index increased, mainly as a result of the desire subscore. This association was more pronounced in the women with unexplained infertility. Reproductive-age women with infertility associated with polycystic ovary syndrome and unexplained infertility, despite phenotypic and biochemical differences in androgenic manifestations, do not manifest clinically significant differences in sexual function. Copyright © 2017 Elsevier Inc. All rights reserved.
Sitnik, Jessica L; Francis, Carmen; Hens, Korneel; Huybrechts, Roger; Wolfner, Mariana F; Callaerts, Patrick
2014-03-01
Members of the M13 class of metalloproteases have been implicated in diseases and in reproductive fitness. Nevertheless, their physiological role remains poorly understood. To obtain a tractable model with which to analyze this protein family's function, we characterized the gene family in Drosophila melanogaster and focused on reproductive phenotypes. The D. melanogaster genome contains 24 M13 class protease homologs, some of which are orthologs of human proteases, including neprilysin. Many are expressed in the reproductive tracts of either sex. Using RNAi we individually targeted the five Nep genes most closely related to vertebrate neprilysin, Nep1-5, to investigate their roles in reproduction. A reduction in Nep1, Nep2, or Nep4 expression in females reduced egg laying. Nep1 and Nep2 are required in the CNS and the spermathecae for wild-type fecundity. Females that are null for Nep2 also show defects as hosts of sperm competition as well as an increased rate of depletion for stored sperm. Furthermore, eggs laid by Nep2 mutant females are fertilized normally, but arrest early in embryonic development. In the male, only Nep1 was required to induce normal patterns of female egg laying. Reduction in the expression of Nep2-5 in the male did not cause any dramatic effects on reproductive fitness, which suggests that these genes are either nonessential for male fertility or perform redundant functions. Our results suggest that, consistent with the functions of neprilysins in mammals, these proteins are also required for reproduction in Drosophila, opening up this model system for further functional analysis of this protein class and their substrates.
Sitnik, Jessica L.; Francis, Carmen; Hens, Korneel; Huybrechts, Roger; Wolfner, Mariana F.; Callaerts, Patrick
2014-01-01
Members of the M13 class of metalloproteases have been implicated in diseases and in reproductive fitness. Nevertheless, their physiological role remains poorly understood. To obtain a tractable model with which to analyze this protein family’s function, we characterized the gene family in Drosophila melanogaster and focused on reproductive phenotypes. The D. melanogaster genome contains 24 M13 class protease homologs, some of which are orthologs of human proteases, including neprilysin. Many are expressed in the reproductive tracts of either sex. Using RNAi we individually targeted the five Nep genes most closely related to vertebrate neprilysin, Nep1-5, to investigate their roles in reproduction. A reduction in Nep1, Nep2, or Nep4 expression in females reduced egg laying. Nep1 and Nep2 are required in the CNS and the spermathecae for wild-type fecundity. Females that are null for Nep2 also show defects as hosts of sperm competition as well as an increased rate of depletion for stored sperm. Furthermore, eggs laid by Nep2 mutant females are fertilized normally, but arrest early in embryonic development. In the male, only Nep1 was required to induce normal patterns of female egg laying. Reduction in the expression of Nep2-5 in the male did not cause any dramatic effects on reproductive fitness, which suggests that these genes are either nonessential for male fertility or perform redundant functions. Our results suggest that, consistent with the functions of neprilysins in mammals, these proteins are also required for reproduction in Drosophila, opening up this model system for further functional analysis of this protein class and their substrates. PMID:24395329
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.
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...
EFFECTS OF METAM SODIUM ON REPRODUCTIVE FUNCTION IN THE FEMALE RAT
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...
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Mastitis effects on reproductive performance in dairy cattle: a review.
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.
Endocrine-active pharmaceuticals that enter the aquatic environment through sewage effluent may have unintended impacts on reproduction in fish, which in turn may affect the sustainability of exposed populations. Laboratory experiments were conducted with the marine fish cunner (...
Endocrine-active pharmaceuticals that enter the aquatic environment through sewage effluent may have unintended impacts on reproduction in fish, which in turn may affect the sustainability of exposed populations. Laboratory experiments were conducted with the marine fish cunner (...
Endocrine-active pharmaceuticals entering the aquatic environment through sewage effluent may have unintended, adverse impacts on the reproduction of aquatic organisms, which in turn may affect the sustainability of exposed populations. Laboratory experiments were conducted with ...
USDA-ARS?s Scientific Manuscript database
Reproductive success is an important component of commercial beef cattle production, and identification of DNA markers with predictive merit for reproductive success would facilitate accurate prediction of mean daughter pregnancy rate, enabling effective selection of bulls to improve female fertilit...
Hormonally mediated effects on the female reproductive system may manifest in pathologic changes of endocrine-responsive organs and altered reproductive function. Identification of these effects requires proper assessment, which may include investigative studies of female reprod...
Surekha, T; Himabindu, Y; Sriharibabu, M; Pandey, Anil Kumar
2014-01-01
Physical inactivity is a leading risk factor for overweight and obesity in the society. Prevalence of overweight and obesity in the reproductive age group women not only affects maternal health but also the health of the off spring. Infertility is a common problem in India affecting 13-19 million people at any given time. Even though it is not life threatening, infertility causes intense mental agony and trauma that can only be best described by infertile couples themselves. Infertility is more common in overweight and obese individuals compared to normal weight individuals. Decreasing ovarian reserve is an important factor for infertility in women. This study examined the impact of physical activity on ovarian reserve markers in normal, overweight and obese reproductive age women. The observations made in this study reveal that physical activity improves ovarian reserve markers in all reproductive age women but this improvement is more distinct and statistically significant in overweight and obese women compared to normal weight women.
Romano, Renata Marino; Gomes, Samantha Nascimento; Cardoso, Nathalia Carolina Scandolara; Schiessl, Larissa; Romano, Marco Aurelio; Oliveira, Claudio Alvarenga
2017-02-01
The impact of thyroid hormone (TH) disorders on male reproductive biology has been a controversial issue for many years. Recently, we reported that hypothyroid male rats have a disruption of the seminiferous epithelium, which may compromise spermatogenesis. To improve the understanding of the reproductive pathogenesis of hypothyroidism and hyperthyroidism, male Wistar rats that developed these dysfunctions in adulthood were used as an experimental model. We evaluated the sperm production, reserves, transit time, morphology, and functionality (acrosome integrity, plasma membrane integrity, and mitochondrial activity), and the testicular expression of the TH receptors (Thra1 and Thra2, Thrb1, and Thrb2), deiodinases (Dio2 and Dio3), and the Mct8 transporter (Slc16a2) were assessed by reverse transcription followed by real-time quantitative PCR (RT-qPCR). The results were evaluated statistically by ANOVA and Tukey HSD test (P < 0.05). Hypothyroidism decreased the total and daily sperm productions and increased the sperm transit time through the epididymis, while the sperm functionality was reduced in both thyroid dysfunctions. Regarding the modulation of gene expression in the testis, hypothyroidism increased the expression of Thra1 and decreased the expression of Dio3, and hyperthyroidism increased the expression of Slc16a2. The observed alterations in spermatic production and function and in the expression of the TH receptor, deiodinase, and the TH transporter are suggestive of TH participation in spermatogenesis in adulthood.
Pretty Good or Pretty Bad? The Ovary and Chemicals in Personal Care Products.
Craig, Zelieann R; Ziv-Gal, Ayelet
2018-04-01
Personal care products (PCP) contain a myriad of chemicals generally formulated to provide a safe and beneficial use. Nonetheless, an increasing amount of laboratory animal and human studies indicate that some chemicals in PCP are associated with decreased hormone production, diminished ovarian reserve, ovarian cancer, and early pregnancy loss. The ovary is key to female fertility by providing the eggs and sex steroid hormones for fertilization and maintenance of reproductive function, respectively. Thus, understanding how chemicals in PCP affect the ovary will shed some light on their potential effects on female fertility. In this review, we provide an overview of: (1) ovarian function as a determinant of fertility in females, (2) the status of knowledge regarding the effects of seven common chemicals in PCP on the ovary, and (3) significant gaps in the literature along with opportunities to eliminate some of the gaps. Findings from the limited existing data suggest that chemicals in PCP such as dibutyl phthalate can reach the ovary in humans and impact its function in animal models. Unfortunately, it is still difficult to assess how relevant findings of experimental studies are to women because of lack of human exposure data for most of these chemicals and the lack of studies that mimic real-life exposures. In contrast to chemicals such as bisphenol A and dioxin, the investigation of the effects of chemicals in PCP on reproductive function is still limited and warrants further investigation to fill existing data gaps.
Prenatal programming of neuroendocrine reproductive function.
Evans, Neil P; Bellingham, Michelle; Robinson, Jane E
2016-07-01
It is now well recognized that the gestational environment can have long-lasting effects not only on the life span and health span of an individual but also, through potential epigenetic changes, on future generations. This article reviews the "prenatal programming" of the neuroendocrine systems that regulate reproduction, with a specific focus on the lessons learned using ovine models. The review examines the critical roles played by steroids in normal reproductive development before considering the effects of prenatal exposure to exogenous steroid hormones including androgens and estrogens, the effects of maternal nutrition and stress during gestation, and the effects of exogenous chemicals such as alcohol and environment chemicals. In so doing, it becomes evident that, to maximize fitness, the regulation of reproduction has evolved to be responsive to many different internal and external cues and that the GnRH neurosecretory system expresses a degree of plasticity throughout life. During fetal life, however, the system is particularly sensitive to change and at this time, the GnRH neurosecretory system can be "shaped" both to achieve normal sexually differentiated function but also in ways that may adversely affect or even prevent "normal function". The exact mechanisms through which these programmed changes are brought about remain largely uncharacterized but are likely to differ depending on the factor, the timing of exposure to that factor, and the species. It would appear, however, that some afferent systems to the GnRH neurons such as kisspeptin, may be critical in this regard as it would appear to be sensitive to a wide variety of factors that can program reproductive function. Finally, it has been noted that the prenatal programming of neuroendocrine reproductive function can be associated with epigenetic changes, which would suggest that in addition to direct effects on the exposed offspring, prenatal programming could have transgenerational effects on reproductive potential. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.
Evolution and functional divergence of NLRP genes in mammalian reproductive systems
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
Apomixis in hawkweed: Mendel's experimental nemesis.
Koltunow, Anna M G; Johnson, Susan D; Okada, Takashi
2011-03-01
Mendel used hawkweeds and other plants to verify the laws of inheritance he discovered using Pisum. Trait segregation was not evident in hawkweeds because many form seeds asexually by apomixis. Meiosis does not occur during female gametophyte formation and the mitotically formed embryo sacs do not require fertilization for seed development. The resulting progeny retain a maternal genotype. Hawkweeds in Hieracium subgenus Pilosella form mitotic embryo sacs by apospory. The initiation of sexual reproduction is required to stimulate apospory in ovules and to promote the function of the dominant locus, LOSS OF APOMEIOSIS, which stimulates the differentiation of somatic aposporous initial (AI) cells near sexually programmed cells. As AI cells undergo nuclear mitosis the sexual pathway terminates. The function of the dominant locus LOSS OF PARTHENOGENESIS in aposporous embryo sacs enables fertilization-independent embryo and endosperm development. Deletion of either locus results in partial reversion to sexual reproduction, and loss of function in both loci results in reversion to sexual development. In these apomicts, sexual reproduction is therefore the default reproductive mode upon which apomixis is superimposed. These loci are unlikely to encode factors critical for sexual reproduction but might recruit the sexual pathway to enable apomixis. Incomplete functional penetrance of these dominant loci is likely to lead to the generation of rare sexual progeny also derived from these facultative apomicts.
Beldade, Ricardo; Blandin, Agathe; O'Donnell, Rory; Mills, Suzanne C
2017-10-10
Organisms can behaviorally, physiologically, and morphologically adjust to environmental variation via integrative hormonal mechanisms, ultimately allowing animals to cope with environmental change. The stress response to environmental and social changes commonly promotes survival at the expense of reproduction. However, despite climate change impacts on population declines and diversity loss, few studies have attributed hormonal stress responses, or their regulatory effects, to climate change in the wild. Here, we report hormonal and fitness responses of individual wild fish to a recent large-scale sea warming event that caused widespread bleaching on coral reefs. This 14-month monitoring study shows a strong correlation between anemone bleaching (zooxanthellae loss), anemonefish stress response, and reproductive hormones that decreased fecundity by 73%. These findings suggest that hormone stress responses play a crucial role in changes to population demography following climate change and plasticity in hormonal responsiveness may be a key mechanism enabling individual acclimation to climate change.Elevated temperatures can cause anemones to bleach, with unknown effects on their associated symbiotic fish. Here, Beldade and colleagues show that climate-induced bleaching alters anemonefish hormonal stress response, resulting in decreased reproductive hormones and severely impacted reproduction.
Age-dependent trade-offs between immunity and male, but not female, reproduction.
McNamara, Kathryn B; van Lieshout, Emile; Jones, Therésa M; Simmons, Leigh W
2013-01-01
Immune function is costly and must be traded off against other life-history traits, such as gamete production. Studies of immune trade-offs typically focus on adult individuals, yet the juvenile stage can be a highly protracted period when reproductive resources are acquired and immune challenges are ubiquitous. Trade-offs during development are likely to be important, yet no studies have considered changes in adult responses to immune challenges imposed at different stages of juvenile development. By manipulating the timing of a bacterial immune challenge to the larvae of the cotton bollworm moth, we examined potential trade-offs between investment into immunity at different stages of juvenile development (early or late) and subsequent adult reproductive investment into sperm or egg production. Our data reveal an age-dependent trade-off between juvenile immune function and adult male reproductive investment. Activation of the immune response during late development resulted in a reduced allocation of resources to eupyrene (fertilizing) sperm production. Immune activation from the injection procedure itself (irrespective of whether individuals were injected with an immune elicitor or a control solution) also caused reproductive trade-offs; males injected early in development produced fewer apyrene (nonfertilizing) sperm. Contrary to many other studies, our study demonstrates these immune trade-offs under ad libitum nutritional conditions. No trade-offs were observed between female immune activation and adult reproductive investment. We suggest the differences in trade-offs observed between male sperm types and the absence of reproductive trade-offs in females may be the result of ontogenetic differences in gamete production in this species. Our data reveal developmental windows when trade-offs between immune function and gametic investment are made, and highlight the importance of considering multiple developmental periods when making inferences regarding the fundamental trade-offs expected between immune function and reproduction. © 2012 The Authors. Journal of Animal Ecology © 2012 British Ecological Society.
Women's health issues with fibromyalgia syndrome.
Shaver, Joan L F; Wilbur, Joellen; Robinson, F Patrick; Wang, Edward; Buntin, Mary S
2006-11-01
Fibromyalgia syndrome (FMS) involves multiple sensory, somatic, and cognitive symptoms that are bound to affect or be affected by physical and mental health status and behavioral components of daily life. From a telephone survey of 442 women with and 205 women without FMS as volunteers, data were compared on (1) general health status, (2) reproductive and sleep-related diagnoses, and (3) lifestyle health behaviors. All multiple or logistics regression analyses for group differences were controlled for age, body mass index (BMI), race, employment status, marital status, having a college degree, low household income, and having ever been diagnosed with depression, with a Bonferroni p value correction for multiple indicators. Accordingly, FMS negatively impacted both perceived physical and mental health status, although relatively more so for physical (p < 0.017). Women with FMS were more likely to have had reproductive health or sleep-related diagnoses, including premenstrual syndrome, dysmenorrhea, breast cysts, bladder cystitis, sleep apnea, restless leg syndrome, and abnormal leg movements (p < 0.0125). They were calculated to use less than half as many calories per week as control women (689 +/- 1293 vs. 1499 +/- 1584 kcal/week, p < 0.05) and had more sleep pattern difficulties (p < 0.0125), more negative changes in sexual function (greater odds for 5 of 10 indicators at p < 0.005), and lower alcohol use (odds ratio = 0.39, p < 0.05). Patients with FMS deserve careful assessment for reproductive conditions and sleep-related functional disorders. Besides more research into mechanisms underlying symptoms, intervention testing specifically to alleviate sleep problems, low physical activity levels, and sexual dysfunction should be paramount.
Silva, Joana Vieira; Cruz, Daniel; Gomes, Mariana; Correia, Bárbara Regadas; Freitas, Maria João; Sousa, Luís; Silva, Vladimiro; Fardilha, Margarida
2017-01-01
Many studies have reported a negative impact of lifestyle factors on testicular function, spermatozoa parameters and pituitary-gonadal axis. However, conclusions are difficult to draw, since studies in the general population are rare. In this study we intended to address the early and late short-term impact of acute lifestyle alterations on young men’s reproductive function. Thirty-six healthy male students, who attended the Portuguese academic festivities, provided semen samples and answered questionnaires at three time-points. The consumption of alcohol and cigarette increased more than 8 and 2 times, respectively, during the academic festivities and resulted in deleterious effects on semen quality: one week after the festivities, a decrease on semen volume, spermatozoa motility and normal morphology was observed, in parallel with an increase on immotile spermatozoa, head and midpiece defects and spermatozoa oxidative stress. Additionally, three months after the academic festivities, besides the detrimental effect on volume, motility and morphology, a negative impact on spermatozoa concentration was observed, along with a decrease on epididymal, seminal vesicles and prostate function. This study contributed to understanding the pathophysiology underlying semen quality degradation induced by acute lifestyle alterations, suggesting that high alcohol and cigarette consumption are associated with decreased semen quality in healthy young men. PMID:28367956
Freeman, Elizabeth W.; Meyer, Jordana M.; Putman, Sarah B.; Schulte, Bruce A.; Brown, Janine L.
2013-01-01
Free-ranging African elephants live in a fission–fusion society, at the centre of which is the matriarch. Matriarchs are generally older females that guide their families to resources and co-ordinate group defense. While much is known about elephant society, knowledge is generally lacking about how age affects the physiology of wild elephants. Investigation of the ovarian activity of free-ranging elephants could provide insight into the reproductive ageing process, with implications for population management. Faecal samples were collected from 46 individuals ranging in age from 14 to 60 years for a 2-year period, and progestagen metabolite analyses were used to examine relationships between social status, age, season, and ovarian activity in female elephants in Addo Elephant National Park, South Africa. Social status was the strongest predictor of faecal progestagen metabolite concentrations in non-pregnant elephants, with grand matriarchs (n = 6) having the lowest values compared with matriarchs (n = 21) and non-matriarch females (n = 19). Likewise, social status and age were the strongest predictors of faecal progestagen metabolite concentrations in pregnant elephants (n = 27). The number of years since a non-pregnant female gave birth to her last calf (post-partum duration) was longer for older females with a higher social status, as well as during the dry season. Our results indicate that social standing and age of elephants are related to reproductive function, and that older females exhibit reductions in ovarian capacity. These results expand our understanding of reproduction and fertility throughout an elephant's lifespan, and the factors that impact gonadal function in free-ranging females. Given that possible over-abundance of elephants in areas such as Addo Elephant National Park is fuelling the debate over how best to manage these populations, knowledge about the reproductive potential of high-ranking females can provide managers with biological data to identify the best candidates for controlling growth through translocation or contraception. PMID:27293609
Gröger, Joachim P; Hinrichsen, Hans-Harald; Polte, Patrick
2014-01-01
Climate forcing in complex ecosystems can have profound implications for ecosystem sustainability and may thus challenge a precautionary ecosystem management. Climatic influences documented to affect various ecological functions on a global scale, may themselves be observed on quantitative or qualitative scales including regime shifts in complex marine ecosystems. This study investigates the potential climatic impact on the reproduction success of spring-spawning herring (Clupea harengus) in the Western Baltic Sea (WBSS herring). To test for climate effects on reproduction success, the regionally determined and scientifically well-documented spawning grounds of WBSS herring represent an ideal model system. Climate effects on herring reproduction were investigated using two global indices of atmospheric variability and sea surface temperature, represented by the North Atlantic Oscillation (NAO) and the Atlantic Multi-decadal Oscillation (AMO), respectively, and the Baltic Sea Index (BSI) which is a regional-scale atmospheric index for the Baltic Sea. Moreover, we combined a traditional approach with modern time series analysis based on a recruitment model connecting parental population components with reproduction success. Generalized transfer functions (ARIMAX models) allowed evaluating the dynamic nature of exogenous climate processes interacting with the endogenous recruitment process. Using different model selection criteria our results reveal that in contrast to NAO and AMO, the BSI shows a significant positive but delayed signal on the annual dynamics of herring recruitment. The westward influence of the Siberian high is considered strongly suppressing the influence of the NAO in this area leading to a higher explanatory power of the BSI reflecting the atmospheric pressure regime on a North-South transect between Oslo, Norway and Szczecin, Poland. We suggest incorporating climate-induced effects into stock and risk assessments and management strategies as part of the EU ecosystem approach to support sustainable herring fisheries in the Western Baltic Sea.
Freeman, Elizabeth W; Meyer, Jordana M; Putman, Sarah B; Schulte, Bruce A; Brown, Janine L
2013-01-01
Free-ranging African elephants live in a fission-fusion society, at the centre of which is the matriarch. Matriarchs are generally older females that guide their families to resources and co-ordinate group defense. While much is known about elephant society, knowledge is generally lacking about how age affects the physiology of wild elephants. Investigation of the ovarian activity of free-ranging elephants could provide insight into the reproductive ageing process, with implications for population management. Faecal samples were collected from 46 individuals ranging in age from 14 to 60 years for a 2-year period, and progestagen metabolite analyses were used to examine relationships between social status, age, season, and ovarian activity in female elephants in Addo Elephant National Park, South Africa. Social status was the strongest predictor of faecal progestagen metabolite concentrations in non-pregnant elephants, with grand matriarchs (n = 6) having the lowest values compared with matriarchs (n = 21) and non-matriarch females (n = 19). Likewise, social status and age were the strongest predictors of faecal progestagen metabolite concentrations in pregnant elephants (n = 27). The number of years since a non-pregnant female gave birth to her last calf (post-partum duration) was longer for older females with a higher social status, as well as during the dry season. Our results indicate that social standing and age of elephants are related to reproductive function, and that older females exhibit reductions in ovarian capacity. These results expand our understanding of reproduction and fertility throughout an elephant's lifespan, and the factors that impact gonadal function in free-ranging females. Given that possible over-abundance of elephants in areas such as Addo Elephant National Park is fuelling the debate over how best to manage these populations, knowledge about the reproductive potential of high-ranking females can provide managers with biological data to identify the best candidates for controlling growth through translocation or contraception.
Gröger, Joachim P.; Hinrichsen, Hans-Harald; Polte, Patrick
2014-01-01
Climate forcing in complex ecosystems can have profound implications for ecosystem sustainability and may thus challenge a precautionary ecosystem management. Climatic influences documented to affect various ecological functions on a global scale, may themselves be observed on quantitative or qualitative scales including regime shifts in complex marine ecosystems. This study investigates the potential climatic impact on the reproduction success of spring-spawning herring (Clupea harengus) in the Western Baltic Sea (WBSS herring). To test for climate effects on reproduction success, the regionally determined and scientifically well-documented spawning grounds of WBSS herring represent an ideal model system. Climate effects on herring reproduction were investigated using two global indices of atmospheric variability and sea surface temperature, represented by the North Atlantic Oscillation (NAO) and the Atlantic Multi-decadal Oscillation (AMO), respectively, and the Baltic Sea Index (BSI) which is a regional-scale atmospheric index for the Baltic Sea. Moreover, we combined a traditional approach with modern time series analysis based on a recruitment model connecting parental population components with reproduction success. Generalized transfer functions (ARIMAX models) allowed evaluating the dynamic nature of exogenous climate processes interacting with the endogenous recruitment process. Using different model selection criteria our results reveal that in contrast to NAO and AMO, the BSI shows a significant positive but delayed signal on the annual dynamics of herring recruitment. The westward influence of the Siberian high is considered strongly suppressing the influence of the NAO in this area leading to a higher explanatory power of the BSI reflecting the atmospheric pressure regime on a North-South transect between Oslo, Norway and Szczecin, Poland. We suggest incorporating climate-induced effects into stock and risk assessments and management strategies as part of the EU ecosystem approach to support sustainable herring fisheries in the Western Baltic Sea. PMID:24586279
GnRH and GnRH receptors in the pathophysiology of the human female reproductive system.
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 the female lifespan; their modulation may offer new possible strategies for diagnostic and therapeutic interventions. A GnRH/GnRHR system is also expressed in female reproductive tissues (e.g. endometrium and ovary), both in normal and pathological conditions. The expression of this system in the human endometrium and ovary supports its physiological regulatory role in the processes of trophoblast invasion of the maternal endometrium and embryo implantation as well as of follicular development and corpus luteum functions. The GnRH/GnRHR system that is expressed in diseased tissues of the female reproductive tract (both benign and malignant) is at present considered an effective molecular target for the development of novel therapeutic approaches for these pathologies. GnRH agonists are also considered as a promising therapeutic approach to counteract ovarian failure in young female patients undergoing chemotherapy. Increasing knowledge about the regulation of GnRH pulsatile release, as well as the therapeutic use of its analogues, offers interesting new perspectives in the diagnosis, treatment and outcome of female reproductive disorders, including tumoral and iatrogenic diseases. © 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.
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
Diamanti-Kandarakis, Evanthia; Papalou, Olga; Kandaraki, Eleni A; Kassi, Georgia
2017-02-01
Nutrition can generate oxidative stress and trigger a cascade of molecular events that can disrupt oxidative and hormonal balance. Nutrient ingestion promotes a major inflammatory and oxidative response at the cellular level in the postprandial state, altering the metabolic state of tissues. A domino of unfavorable metabolic changes is orchestrated in the main metabolic organs, including adipose tissue, skeletal muscle, liver and pancreas, where subclinical inflammation, endothelial dysfunction, mitochondrial deregulation and impaired insulin response and secretion take place. Simultaneously, in reproductive tissues, nutrition-induced oxidative stress can potentially violate delicate oxidative balance that is mandatory to secure normal reproductive function. Taken all the above into account, nutrition and its accompanying postprandial oxidative stress, in the unique context of female hormonal background, can potentially compromise normal metabolic and reproductive functions in women and may act as an active mediator of various metabolic and reproductive disorders. © 2017 European Society of Endocrinology.
Kisspeptin modulates sexual and emotional brain processing in humans
Comninos, Alexander N.; Wall, Matthew B.; Demetriou, Lysia; Shah, Amar J.; Clarke, Sophie A.; Narayanaswamy, Shakunthala; Nesbitt, Alexander; Izzi-Engbeaya, Chioma; Prague, Julia K.; Abbara, Ali; Ratnasabapathy, Risheka; Salem, Victoria; Nijher, Gurjinder M.; Jayasena, Channa N.; Tanner, Mark; Bassett, Paul; Mehta, Amrish; Rabiner, Eugenii A.; Hönigsperger, Christoph; Silva, Meire Ribeiro; Brandtzaeg, Ole Kristian; Wilson, Steven Ray; Brown, Rachel C.; Thomas, Sarah A.; Bloom, Stephen R.; Dhillo, Waljit S.
2017-01-01
BACKGROUND. Sex, emotion, and reproduction are fundamental and tightly entwined aspects of human behavior. At a population level in humans, both the desire for sexual stimulation and the desire to bond with a partner are important precursors to reproduction. However, the relationships between these processes are incompletely understood. The limbic brain system has key roles in sexual and emotional behaviors, and is a likely candidate system for the integration of behavior with the hormonal reproductive axis. We investigated the effects of kisspeptin, a recently identified key reproductive hormone, on limbic brain activity and behavior. METHODS. Using a combination of functional neuroimaging and hormonal and psychometric analyses, we compared the effects of kisspeptin versus vehicle administration in 29 healthy heterosexual young men. RESULTS. We demonstrated that kisspeptin administration enhanced limbic brain activity specifically in response to sexual and couple-bonding stimuli. Furthermore, kisspeptin’s enhancement of limbic brain structures correlated with psychometric measures of reward, drive, mood, and sexual aversion, providing functional significance. In addition, kisspeptin administration attenuated negative mood. CONCLUSIONS. Collectively, our data provide evidence of an undescribed role for kisspeptin in integrating sexual and emotional brain processing with reproduction in humans. These results have important implications for our understanding of reproductive biology and are highly relevant to the current pharmacological development of kisspeptin as a potential therapeutic agent for patients with common disorders of reproductive function. FUNDING. National Institute for Health Research (NIHR), Wellcome Trust (Ref 080268), and the Medical Research Council (MRC). PMID:28112678
USDA-ARS?s Scientific Manuscript database
In lower termites, functionally sterile larval helpers are totipotent, capable of becoming reproductively active with the loss of their colony’s king or queen. Full reproductive development may take several weeks, but initiation of this response most likely occurs shortly after colony members detect...
The JH1 Haplotype-a newly discovered marker for infertility in the jersy breed
USDA-ARS?s Scientific Manuscript database
The focus on production traits in genetic selection programs with little consideration for traits associated with reproduction has contributed to the decline in reproductive function. Moreover, there is a negative genetic correlation between milk yield and reproduction so that selection for yield ca...
A short-term reproduction assay with the fathead minnow has been developed to detect chemicals with the potential to disrupt reproductive endocrine functions controlled by estrogen- and androgen-mediated pathways. The objective of this study was to characterize the responses of t...
Measuring reproductive tourism through an analysis of Indian ART clinic Websites.
Deonandan, Raywat; Loncar, Mirhad; Rahman, Prinon; Omar, Sabrina
2012-01-01
India is fast becoming the most prominent player in the global industry of reproductive tourism, in which infertile people cross international borders to seek assisted reproduction technologies. This study was conducted to better understand the extent and manner in which Indian clinics seek foreign clients. A systematic search of official Indian assisted reproduction technologies clinic Websites was undertaken, and instances noted where foreign clients were overtly targeted, and where maternal surrogacy was overtly offered. A total of 159 clinics with Web addresses were identified, though only 78 had functioning Websites. All were published in English, with the majority clustered in the states of Maharashtra (14) and Gujarat (9). Of the 78 functioning Websites, 53 (68%) featured some mention of maternal surrogacy services, and 42 (54%) made overt overtures to foreign clients. Qualitative appeals to foreigners included instructions for international adoption, visa application, and the legal parental disposition of the surrogate. All Maharashtran clinic Websites that mentioned surrogacy also overtly featured reproductive tourism. Preimplantation diagnosis services were not offered disproportionately by clinics mentioning reproductive tourism. Based upon clinic online profiles, reproductive tourism comprises a substantial fraction of India's assisted reproduction technologies clinics' business focus, clustering around its most tourist-friendly locales, and surrogacy may be a strong motivator for international clientele.
Stallion fertility: a focus on the spermatozoon.
Varner, D D; Gibb, Z; Aitken, R J
2015-01-01
Stallion fertility is a vast subject, with a wide array of permutations that can impact reproductive performance in either positive or negative ways. This review is intended to address a mere segment of the male fertility issue, but the very essence of the male contribution to fertilisation, that of the spermatozoon. Spermatozoal ultrastructure and form-to-function are detailed and spermatozoal metabolism is discussed, with specific reference to distinctive characteristics of stallion spermatozoa. Lastly, methods for assessment of spermatozoal function are considered, with emphasis on spermatozoal motility, the acrosome reaction and spermatozoon-oocyte interactions. Closing comments address the need for development and standardisation of molecular-based assays for use with spermatozoa of stallions whose subfertility cannot be explained with conventional tests. © 2014 EVJ Ltd.
Neuronal Organization of Deep Brain Opsin Photoreceptors in Adult Teleosts
Hang, Chong Yee; Kitahashi, Takashi; Parhar, Ishwar S.
2016-01-01
Biological impacts of light beyond vision, i.e., non-visual functions of light, signify the need to better understand light detection (or photoreception) systems in vertebrates. Photopigments, which comprise light-absorbing chromophores bound to a variety of G-protein coupled receptor opsins, are responsible for visual and non-visual photoreception. Non-visual opsin photopigments in the retina of mammals and extra-retinal tissues of non-mammals play an important role in non-image-forming functions of light, e.g., biological rhythms and seasonal reproduction. This review highlights the role of opsin photoreceptors in the deep brain, which could involve conserved neurochemical systems that control different time- and light-dependent physiologies in in non-mammalian vertebrates including teleost fish. PMID:27199680
Kasl, Emily L; McAllister, Chris T; Robison, Henry W; Connior, Matthew B; Font, William F; Criscione, Charles D
2015-12-01
The evolutionary consequences of changes in the complex life cycles of parasites are not limited to the traits that directly affect transmission. For instance, mating systems that are altered due to precocious sexual maturation in what is typically regarded as an intermediate host may impact opportunities for outcrossing. In turn, reproductive traits may evolve to optimize sex allocation. Here, we test the hypothesis that sex allocation evolved toward a more female-biased function in populations of the hermaphroditic digenean trematode Alloglossidium progeneticum that can precociously reproduce in their second hosts. In these precocious populations, parasites are forced to self-fertilize as they remain encysted in their second hosts. In contrast, parasites in obligate three-host populations have more opportunities to outcross in their third host. We found strong support that in populations with precocious development, allocation to male resources was greatly reduced. We also identified a potential phenotypically plastic response in a body size sex allocation relationship that may be driven by the competition for mates. These results emphasize how changes in life cycle patterns that alter mating systems can impact the evolution of reproductive traits in parasites. © 2015 The Author(s). Evolution © 2015 The Society for the Study of Evolution.
Effects of environmental change on wildlife health
Acevedo-Whitehouse, Karina; Duffus, Amanda L. J.
2009-01-01
Environmental change has negatively affected most biological systems on our planet and is becoming of increasing concern for the well-being and survival of many species. At an organism level, effects encompass not only endocrine disruptions, sex-ratio changes and decreased reproductive parameters, but also include teratogenic and genotoxic effects, immunosuppression and other immune-system impairments that can lead directly to disease or increase the risk of acquiring disease. Living organisms will strive to maintain health by recognizing and resolving abnormal situations, such as the presence of invading microorganisms or harmful peptides, abnormal cell replication and deleterious mutations. However, fast-paced environmental changes may pose additional pressure on immunocompetence and health maintenance, which may seriously impact population viability and persistence. Here, we outline the importance of a functional immune system for survival and examine the effects that exposure to a rapidly changing environment might exert on immunocompetence. We then address the various levels at which anthropogenic environmental change might affect wildlife health and identify potential deficits in reproductive parameters that might arise owing to new immune challenges in the context of a rapidly changing environment. Throughout the paper, a series of examples and case studies are used to illustrate the impact of environmental change on wildlife health. PMID:19833653
Pertynska-Marczewska, Magdalena; Cypryk, Katarzyna
2017-09-01
Diabetes mellitus (DM) is a group of metabolic disorders of carbohydrate metabolism in which glucose is underutilized, resulting in hyperglycemia. Reproductive impairment in poorly controlled diabetes mellitus type 1 (T1DM) results from a combined effect of insulin deficiency and hyperglycemia that disrupt the functioning of metabolic signals participating in the regulation of the reproductive system. Good metabolic control as a result of intensive insulin therapy has a great impact on the fertility and childbearing possibilities in the T1DM females. Advanced glycation end products (AGEs) are formed by nonenzymatic modification of proteins, lipids, and nucleic acids by glucose. The formation and accumulation of AGEs are known to progress at an accelerated rate in diabetes. AGEs either act on the pro-inflammatory cell surface receptors called RAGE or bind to the circulating anti-inflammatory sRAGE that prevents activation of cell-surface RAGE by AGEs and other proinflammatory ligands. Pregnancy has been found to induce a significant increase in RAGE protein levels in both myometrium and omental vasculature. This review will focus on the role of AGEs and RAGE in pregnancy complicated by DM type 1 as well as ways to reduce the rate of congenital malformations in the offspring of diabetic type 1 women.
Laboratory experiments were conducted with the marine fish cunner (Tautogolabrus adspersus) to evaluate whether four pharmaceuticals used in breast cancer treatment have an impact on reproduction or aromatase activity. Tamoxifen binds to estrogen receptors, while anastrozole, let...
Chemicals in the environment have the potential to cause reproductive toxicity by acting on the hypothalamus-pituitary-gonadal (HPG) axis. We have developed a mathematical model to predict chemical impacts on reproductive hormone production in the highly conserved HPG axis using...
EFFECTS OF METHYL MERCURY ON REPRODUCTION IN AMERICAN KESTRELS
This presentation contains results of a study of the impact of methyl mercury on reproduction of American kestrels. Egg production, incubation performance, and the number of eggs hatched markedly decreased between exposures of 3.2 and 4.6 ppm methyl mercury dry weight in the diet...
Abrams, Elizabeth T; Miller, Elizabeth M
2011-01-01
Life history theory posits that, as long as survival is assured, finite resources are available for reproduction, maintenance, and growth/storage. To maximize lifetime reproductive success, resources are subject to trade-offs both within individuals and between current and future investment. For women, reproducing is costly and time-consuming; the bulk of available resources must be allocated to reproduction at the expense of more flexible systems like immune function. When reproducing women contract infectious diseases, the resources required for immune activation can fundamentally shift the patterns of resource allocation. Adding to the complexity of the reproductive-immune trade-offs in women are the pleiotropic effects of many immune factors, which were modified to serve key roles in mammalian reproduction. In this review, we explore the complex intersections between immune function and female reproduction to situate proximate immunological processes within a life history framework. After a brief overview of the immune system, we discuss some important physiological roles of immune factors in women's reproduction and the conflicts that may arise when these factors must play dual roles. We then discuss the influence of reproductive-immune trade-offs on the patterning of lifetime reproductive success: (1) the effect of immune activation/infectious disease on the timing of life history events; (2) the role of the immune system, immune activation, and infectious disease on resource allocation within individual reproductive events, particularly pregnancy; and (3) the role of the immune system in shaping the offspring's patterns of future life history trade-offs. We close with a discussion of future directions in reproductive immunology for anthropologists. Copyright © 2011 Wiley Periodicals, Inc.
Liver ERα regulates AgRP neuronal activity in the arcuate nucleus of female mice.
Benedusi, Valeria; Della Torre, Sara; Mitro, Nico; Caruso, Donatella; Oberto, Alessandra; Tronel, Claire; Meda, Clara; Maggi, Adriana
2017-04-26
Recent work revealed the major role played by liver Estrogen Receptor α (ERα) in the regulation of metabolic and reproductive functions. By using mutant mice with liver-specific ablation of Erα, we here demonstrate that the hepatic ERα is essential for the modulation of the activity of Agouti Related Protein (AgRP) neurons in relation to the reproductive cycle and diet. Our results suggest that the alterations of hepatic lipid metabolism due to the lack of liver ERα activity are responsible for a neuroinflammatory status that induces refractoriness of AgRP neurons to reproductive and dietary stimuli. The study therefore points to the liver ERα as a necessary sensor for the coordination of systemic energy metabolism and reproductive functions.
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.
Sex steroids effects in normal endocrine pancreatic function and diabetes.
Morimoto, Sumiko; Jiménez-Trejo, Francisco; Cerbón, Marco
2011-01-01
Traditionally the role of sexual steroid hormones was focused primarily on reproductive organs: the breast, female reproductive tract (uterus, mammary gland, and ovary), and male reproductive tract (testes, epididymis and prostate), however our current understanding of tissue-specific effects of sex steroids has elucidated new aspects in its functionality. Recent data have shown that many other tissues are targets of those hormones in addition to classical reproductive organs. The pancreas (which performs both endocrine and exocrine functions), has proven to be an extragonadal target of sexual steroid hormone action. The endocrine pancreas has a pivotal role on carbohydrate homeostasis and deterioration in function produces diabetes. Diabetes is a metabolic disorder that has high prevalence worldwide, particularly in developing countries. It has been shown that steroid hormones have an important role in susceptibility and development of diabetes in animal models, in humans its role is less clear, however the most evident effect is on the perimenopausal women, in this stage the decrease in gonadal steroids produces an increase on susceptibility to develop diabetes mellitus; in men, hypoandrogenism is associated with an increased prevalence of insulin resistance. This review focused on the effects of sexual steroids on pancreatic function and diabetes.
Yin, Shanshan; Tang, Mengling; Chen, Fangfang; Li, Tianle; Liu, Weiping
2017-01-01
Polycyclic aromatic hydrocarbons (PAHs) are a type of ubiquitous pollutant with the potential ability to cause endocrine disruption that would have an adverse health impact on the general population. To assess the maternal exposure to PAHs in neonates and evaluate the possible impact of PAHs on reproductive hormone levels, the concentration of PAHs and reproductive hormone levels in the umbilical cord serum of 98 mother-infant pairs in the Shengsi Islands were investigated. The median concentration of total PAHs was determined to be 164 (Inter-Quartile Range, IQR 93.6-267) ng g -1 lipid, and 68% of the PAHs were lower-molecule congeners. The highest level was found for pyrene (PYR) and naphthalene (NAP), which contributed 54.6% of all the PAHs present in the samples. The exposure to PAHs negatively affected estradiol (E2) and Anti-Mullerian hormones (AMH) and positively affected FSH in the umbilical cord serum. The result expanded the database of the human burden of PAHs and suggested that PAHs can act as a type of Endocrine-Disrupting Chemical (EDC). These results may help to understand the complex pathways involved in disorders of human reproductive health associated with prenatal exposure to PAHs. Copyright © 2016 Elsevier Ltd. All rights reserved.
Scale dependent behavioral responses to human development by a large predator, the puma.
Wilmers, Christopher C; Wang, Yiwei; Nickel, Barry; Houghtaling, Paul; Shakeri, Yasaman; Allen, Maximilian L; Kermish-Wells, Joe; Yovovich, Veronica; Williams, Terrie
2013-01-01
The spatial scale at which organisms respond to human activity can affect both ecological function and conservation planning. Yet little is known regarding the spatial scale at which distinct behaviors related to reproduction and survival are impacted by human interference. Here we provide a novel approach to estimating the spatial scale at which a top predator, the puma (Puma concolor), responds to human development when it is moving, feeding, communicating, and denning. We find that reproductive behaviors (communication and denning) require at least a 4× larger buffer from human development than non-reproductive behaviors (movement and feeding). In addition, pumas give a wider berth to types of human development that provide a more consistent source of human interference (neighborhoods) than they do to those in which human presence is more intermittent (arterial roads with speeds >35 mph). Neighborhoods were a deterrent to pumas regardless of behavior, while arterial roads only deterred pumas when they were communicating and denning. Female pumas were less deterred by human development than males, but they showed larger variation in their responses overall. Our behaviorally explicit approach to modeling animal response to human activity can be used as a novel tool to assess habitat quality, identify wildlife corridors, and mitigate human-wildlife conflict.
Silva, Catarina S; Puranik, Sriharsha; Round, Adam; Brennich, Martha; Jourdain, Agnès; Parcy, François; Hugouvieux, Veronique; Zubieta, Chloe
2015-01-01
Understanding the evolutionary leap from non-flowering (gymnosperms) to flowering (angiosperms) plants and the origin and vast diversification of the floral form has been one of the focuses of plant evolutionary developmental biology. The evolving diversity and increasing complexity of organisms is often due to relatively small changes in genes that direct development. These "developmental control genes" and the transcription factors (TFs) they encode, are at the origin of most morphological changes. TFs such as LEAFY (LFY) and the MADS-domain TFs act as central regulators in key developmental processes of plant reproduction including the floral transition in angiosperms and the specification of the male and female organs in both gymnosperms and angiosperms. In addition to advances in genome wide profiling and forward and reverse genetic screening, structural techniques are becoming important tools in unraveling TF function by providing atomic and molecular level information that was lacking in purely genetic approaches. Here, we summarize previous structural work and present additional biophysical and biochemical studies of the key master regulators of plant reproduction - LEAFY and the MADS-domain TFs SEPALLATA3 and AGAMOUS. We discuss the impact of structural biology on our understanding of the complex evolutionary process leading to the development of the bisexual flower.
Buchman, N; Cuddington, K
2009-08-01
It has been claimed that plant architecture can alter aphid reproductive rates, but the mechanism driving this effect has not been identified. We studied interactions between plant architecture, aphid density, environmental conditions, and nutrient availability on the reproduction of pea aphids [Acyrthosiphon pisum (Harris)] using four near-isogenic peas (Pisum sativum L.) that differ in morphology. Manipulations of aphid density (1, 5, and 10 adults per plant) allowed us to examine any effects of plant morphology on crowding and consequently reproduction. Pea morphology per se did not alter pea aphid crowding, as measured by mean nearest neighbor distance, and there was no effect on reproduction. In addition, reproduction increased with increasing adult density, indicating positive density dependence. In a separate experiment, peas were fertilized to determine whether differences between nutrient availability of the four different morphologies might drive any observed differences in aphid reproduction. Although plant nitrogen content was altered by fertilization treatments, this did not have an impact on aphid reproduction. Greenhouse experiments, however, suggested that pea morphology can interact with environmental conditions to reduce aphid reproduction under some conditions. We conclude that plant morphology only influences aphid reproduction when environmental conditions are less than optimal.
Biological testing of a digested sewage sludge and derived composts.
Moreira, R; Sousa, J P; Canhoto, C
2008-11-01
Aiming to evaluate a possible loss of soil habitat function after amendment with organic wastes, a digested sewage sludge and derived composts produced with green residues, where biologically tested in the laboratory using soil animals (Eisenia andrei and Folsomia candida) and plants (Brassica rapa and Avena sativa). Each waste was tested mimicking a field application of 6ton/ha or 12ton/ha. Avoidance tests did not reveal any impact of sludge and composts to soil biota. Germination and growth tests showed that application of composts were beneficial for both plants. Composts did not affect earthworm's mass increase or reproduction, but the highest sludge amendment revealed negative effects on both parameters. Only the amendment of composts at the highest dose originated an impairment of springtails reproductive output. We suggest that bioassays using different test species may be an additional tool to evaluate effects of amendment of organic wastes in soil. Biological tests are sensitive to pollutants at low concentrations and to interactions undetected by routine chemical analysis.
[Research progress of health effect of polybrominated diphenyl ethers].
Zhai, J X; Tong, S L
2016-06-01
Polybrominated diphenyl ethers (PBDEs) was one of the most common brominated flame retardants, it has been widely used in products such as furnitures, polymer and plastical material, textiles, electronic products and building materials. PBDEs have potential effect such as neurodevelopmental toxicity, reproductive toxicity, thyroid toxicity, immunological toxicity, embryo toxicity, liver toxicity, teratogenicity and potential carcinogenicity. This paper was aimed to review the environmental exposure way, current level, neurotoxicity, neurodevelopmental toxicity and reproductive toxicity of PBDEs. In recent years, PBDEs has been detected in environment, wildlife animal and human body around the world, there were the significant differences of exposure levels of PBDEs. The most abundant congener were tetra-BDE or BDE-47, hexa-BDE or BDE-153, and deca-BDE or BDE-209. Prenatal exposure to PBDEs has great impact on the infants' neurodevelopmental function, induces changes in neuropsychological developmental behavior, decreases of congnition, motivation and attention. High levels of PBDEs have positive relationship with Luteinizing hormone levels, testis disfunction and children's cryptorchidism, and have negative relationship with sperm number and testis size.
Hormonally active phytochemicals and vertebrate evolution.
Lambert, Max R; Edwards, Thea M
2017-06-01
Living plants produce a diversity of chemicals that share structural and functional properties with vertebrate hormones. Wildlife species interact with these chemicals either through consumption of plant materials or aquatic exposure. Accumulating evidence shows that exposure to these hormonally active phytochemicals (HAPs) often has consequences for behavior, physiology, and fecundity. These fitness effects suggest there is potential for an evolutionary response by vertebrates to HAPs. Here, we explore the toxicological HAP-vertebrate relationship in an evolutionary framework and discuss the potential for vertebrates to adapt to or even co-opt the effects of plant-derived chemicals that influence fitness. We lay out several hypotheses about HAPs and provide a path forward to test whether plant-derived chemicals influence vertebrate reproduction and evolution. Studies of phytochemicals with direct impacts on vertebrate reproduction provide an obvious and compelling system for studying evolutionary toxicology. Furthermore, an understanding of whether animal populations evolve in response to HAPs could provide insightful context for the study of rapid evolution and how animals cope with chemical agents in the environment.
EFFECTS OF 3 WEEK EXPOSURES TO METAM SODIUM ON REPRODUCTIVE FUNCTION IN THE FEMALE RAT
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
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...
Direct effects of leptin and adiponectin on peripheral reproductive tissues: a critical review
Kawwass, Jennifer F.; Summer, Ross; Kallen, Caleb B.
2015-01-01
Obesity is a risk factor for infertility and adverse reproductive outcomes. Adipose tissue is an important endocrine gland that secretes a host of endocrine factors, called adipokines, which modulate diverse physiologic processes including appetite, metabolism, cardiovascular function, immunity and reproduction. Altered adipokine expression in obese individuals has been implicated in the pathogenesis of a host of health disorders including diabetes and cardiovascular disease. It remains unclear whether adipokines play a significant role in the pathogenesis of adverse reproductive outcomes in obese individuals and, if so, whether the adipokines are acting directly or indirectly on the peripheral reproductive tissues. Many groups have demonstrated that receptors for the adipokines leptin and adiponectin are expressed in peripheral reproductive tissues and that these adipokines are likely, therefore, to exert direct effects on these tissues. Many groups have tested for direct effects of leptin and adiponectin on reproductive tissues including the testis, ovary, uterus, placenta and egg/embryo. The hypothesis that decreased fertility potential or adverse reproductive outcomes may result, at least in part, from defects in adipokine signaling within reproductive tissues has also been tested. Here, we present a critical analysis of published studies with respect to two adipokines, leptin and adiponectin, for which significant data have been generated. Our evaluation reveals significant inconsistencies and methodological limitations regarding the direct effects of these adipokines on peripheral reproductive tissues. We also observe a pervasive failure to account for in vivo data that challenge observations made in vitro. Overall, while leptin and adiponectin may directly modulate peripheral reproductive tissues, existing data suggest that these effects are minor and non-essential to human or mouse reproductive function. Current evidence suggests that direct effects of leptin or adiponectin on peripheral reproductive tissues are unlikely to factor significantly in the adverse reproductive outcomes observed in obese individuals. PMID:25964237
Similar Gender Dimorphism in the Costs of Reproduction across the Geographic Range of Fraxinus ornus
Verdú, Miguel; Spanos, Kostas; čaňová, Ingrid; Slobodník, Branko; Paule, Ladislav
2007-01-01
Background and Aims The reproductive costs for individuals with the female function have been hypothesized to be greater than for those with the male function because the allocation unit per female flower is very high due to the necessity to nurture the embryos until seed dispersal occurs, while the male reproductive allocation per flower is lower because it finishes once pollen is shed. Consequently, males may invest more resources in growth than females. This prediction was tested across a wide geographical range in a tree with a dimorphic breeding system (Fraxinus ornus) consisting of males and hermaphrodites functioning as females. The contrasting ecological conditions found across the geographical range allowed the evaluation of the hypothesis that the reproductive costs of sexual dimorphism varies with environmental stressors. Methods By using random-effects meta-analysis, the differences in the reproductive and vegetative investment of male and hermaphrodite trees of F. ornus were analysed in 10 populations from the northern (Slovakia), south-eastern (Greece) and south-western (Spain) limits of its European distribution. The variation in gender-dimorphism with environmental stress was analysed by running a meta-regression between these effect sizes and the two environmental stress indicators: one related to temperature (the frost-free period) and another related to water availability (moisture deficit). Key Results Most of the effect sizes showed that males produced more flowers and grew more quickly than hermaphrodites. Gender differences in reproduction and growth were not minimized or maximized under adverse climatic conditions such as short frost-free periods or severe aridity. Conclusions The lower costs of reproduction for F. ornus males allow them to grow more quickly than hermaphrodites, although such differences in sex-specific reproductive costs are not magnified under stressful conditions. PMID:17098751
Role of vitamin D in ovarian physiology and its implication in reproduction: a systematic review.
Irani, Mohamad; Merhi, Zaher
2014-08-01
To report an update on the role of vitamin D (VD) in ovarian physiology with a focus on genes involved in steroidogenesis, follicular development, and ovarian reserve, as well as ovulatory dysfunction associated with polycystic ovary syndrome (PCOS), and ovarian response to assisted reproductive technology (ART). Systematic review. Not applicable. Human, animal, and cell culture models. Pubmed literature search. Granulosa cell function, serum antimüllerian hormone (AMH), AMH and its receptor gene expression, soluble receptor for advanced glycation end-products (sRAGE), PCOS parameters, and ART outcome. In human granulosa cells, VD alters AMH signaling, FSH sensitivity, and progesterone production and release, indicating a possible physiologic role for VD in ovarian follicular development and luteinization. In the serum, 25-hydroxyvitamin D (25OH-D) is positively correlated with AMH, and appropriate VD supplementation in VD-depleted women can suppress the seasonal changes that occur in serum AMH. In VD-deficient women with PCOS, VD supplementation lowers the abnormally elevated serum AMH levels, possibly indicating a mechanism by which VD improves folliculogenesis. The antiinflammatory sRAGE serum levels significantly increase in women with PCOS after VD replacement. Although follicular fluid 25OH-D correlates with IVF outcomes, there is a lack of data pertaining to the impact of VD supplementation on pregnancy rates following IVF. This review underscores the need for understanding the mechanistic actions of VD in ovarian physiology and the critical need for randomized trials to elucidate the impact of VD supplementation on controlled ovarian hyperstimulation/IVF outcome and ovulatory dysfunction associated with PCOS. Copyright © 2014 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.
A Computational Model of the Rainbow Trout Hypothalamus-Pituitary-Ovary-Liver Axis
Gillies, Kendall; Krone, Stephen M.; Nagler, James J.; Schultz, Irvin R.
2016-01-01
Reproduction in fishes and other vertebrates represents the timely coordination of many endocrine factors that culminate in the production of mature, viable gametes. In recent years there has been rapid growth in understanding fish reproductive biology, which has been motivated in part by recognition of the potential effects that climate change, habitat destruction and contaminant exposure can have on natural and cultured fish populations. New approaches to understanding the impacts of these stressors are being developed that require a systems biology approach with more biologically accurate and detailed mathematical models. We have developed a multi-scale mathematical model of the female rainbow trout hypothalamus-pituitary-ovary-liver axis to use as a tool to help understand the functioning of the system and for extrapolation of laboratory findings of stressor impacts on specific components of the axis. The model describes the essential endocrine components of the female rainbow trout reproductive axis. The model also describes the stage specific growth of maturing oocytes within the ovary and permits the presence of sub-populations of oocytes at different stages of development. Model formulation and parametrization was largely based on previously published in vivo and in vitro data in rainbow trout and new data on the synthesis of gonadotropins in the pituitary. Model predictions were validated against several previously published data sets for annual changes in gonadotropins and estradiol in rainbow trout. Estimates of select model parameters can be obtained from in vitro assays using either quantitative (direct estimation of rate constants) or qualitative (relative change from control values) approaches. This is an important aspect of mathematical models as in vitro, cell-based assays are expected to provide the bulk of experimental data for future risk assessments and will require quantitative physiological models to extrapolate across biological scales. PMID:27096735
A Computational Model of the Rainbow Trout Hypothalamus-Pituitary-Ovary-Liver Axis.
Gillies, Kendall; Krone, Stephen M; Nagler, James J; Schultz, Irvin R
2016-04-01
Reproduction in fishes and other vertebrates represents the timely coordination of many endocrine factors that culminate in the production of mature, viable gametes. In recent years there has been rapid growth in understanding fish reproductive biology, which has been motivated in part by recognition of the potential effects that climate change, habitat destruction and contaminant exposure can have on natural and cultured fish populations. New approaches to understanding the impacts of these stressors are being developed that require a systems biology approach with more biologically accurate and detailed mathematical models. We have developed a multi-scale mathematical model of the female rainbow trout hypothalamus-pituitary-ovary-liver axis to use as a tool to help understand the functioning of the system and for extrapolation of laboratory findings of stressor impacts on specific components of the axis. The model describes the essential endocrine components of the female rainbow trout reproductive axis. The model also describes the stage specific growth of maturing oocytes within the ovary and permits the presence of sub-populations of oocytes at different stages of development. Model formulation and parametrization was largely based on previously published in vivo and in vitro data in rainbow trout and new data on the synthesis of gonadotropins in the pituitary. Model predictions were validated against several previously published data sets for annual changes in gonadotropins and estradiol in rainbow trout. Estimates of select model parameters can be obtained from in vitro assays using either quantitative (direct estimation of rate constants) or qualitative (relative change from control values) approaches. This is an important aspect of mathematical models as in vitro, cell-based assays are expected to provide the bulk of experimental data for future risk assessments and will require quantitative physiological models to extrapolate across biological scales.
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.
The SLIT/ROBO pathway: a regulator of cell function with implications for the reproductive system
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.
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.
ERIC Educational Resources Information Center
Orgebin-Crist, Marie-Claire; And Others
In this report, emphasis is placed on major research developments in the reproductive sciences, their impact on the health of individuals as well as on that of society, and on current trends that may provide new opportunities for future research in fertility and infertility. In the first section, major developments in the reproductive sciences are…
CNV analysis of host responses to porcine reproductive and respiratory syndrome virus infection
USDA-ARS?s Scientific Manuscript database
Porcine reproductive and respiratory syndrome (PRRS) is a devastating disease with a significant impact on the swine industry causing major economic losses. Recent studies revealed a region on Sus Scrofa chromosome (SSC) 4 associated with serum viremia and weight gain in pigs infected with the PRRS ...
Genome-wide mapping of loci explaining variance in scrotal circumference in Nellore cattle
USDA-ARS?s Scientific Manuscript database
The reproductive performance of bulls has a high impact on the beef cattle industry. Scrotal circumference (SC) is the most recorded reproductive trait in beef herds, and is used as a major selection criterion to improve precocity and fertility. The characterization of genomic regions affecting SC...
Reproductive allocation and nutrient relationships in Cuphea: A semi-domesticated oilseed crop
USDA-ARS?s Scientific Manuscript database
No information is available on allometric variations in C, N, and P in structural, reproductive and metabolic tissues and their ratios in Cuphea germplasm line PSR23, a semi-domesticated indeterminate and phenotypically plastic oilseed crop. The objectives of this study were to quantify the impact o...
Genome-wide association study of swine farrowing traits. Part II: Bayesian analysis of marker data
USDA-ARS?s Scientific Manuscript database
Reproductive efficiency has a great impact on the economic success of pork production. Number born alive (NBA) and average piglet birth weight (ABW) contribute greatly to reproductive efficiency. To better understand the underlying genetics of birth traits, a genome wide association study (GWAS) w...
Sita, Kumari; Sehgal, Akanksha; Kumar, Jitendra; Kumar, Shiv; Singh, Sarvjeet; Siddique, Kadambot H. M.; Nayyar, Harsh
2017-01-01
Rising temperatures are proving detrimental for various agricultural crops. Cool-season legumes such as lentil (Lens culunaris Medik.) are sensitive to even small increases in temperature during the reproductive stage, hence the need to explore the available germplasm for heat tolerance as well as its underlying mechanisms. In the present study, a set of 38 core lentil accessions were screened for heat stress tolerance by sowing 2 months later (first week of January; max/min temperature >32/20°C during the reproductive stage) than the recommended date of sowing (first week of November; max/min temperature <32/20°C during the reproductive stage). Screening revealed some promising heat-tolerant genotypes (IG2507, IG3263, IG3297, IG3312, IG3327, IG3546, IG3330, IG3745, IG4258, and FLIP2009) which can be used in a breeding program. Five heat-tolerant (HT) genotypes (IG2507, IG3263, IG3745, IG4258, and FLIP2009) and five heat-sensitive (HS) genotypes (IG2821, IG2849, IG4242, IG3973, IG3964) were selected from the screened germplasm and subjected to further analysis by growing them the following year under similar conditions to probe the mechanisms associated with heat tolerance. Comparative studies on reproductive function revealed significantly higher pollen germination, pollen viability, stigmatic function, ovular viability, pollen tube growth through the style, and pod set in HT genotypes under heat stress. Nodulation was remarkably higher (1.8–22-fold) in HT genotypes. Moreover, HT genotypes produced more sucrose in their leaves (65–73%) and anthers (35–78%) that HS genotypes, which was associated with superior reproductive function and nodulation. Exogenous supplementation of sucrose to in vitro-grown pollen grains, collected from heat-stressed plants, enhanced their germination ability. Assessment of the leaves of HT genotypes suggested significantly less damage to membranes (1.3–1.4-fold), photosynthetic function (1.14–1.17-fold) and cellular oxidizing ability (1.1–1.5-fold) than HS genotypes, which was linked to higher relative leaf water content (RLWC) and stomatal conductance (gS). Consequently, HT genotypes had less oxidative damage (measured as malondialdehyde and hydrogen peroxide concentration), coupled with a higher expression of antioxidants, especially those of the ascorbate–glutathione pathway. Controlled environment studies on contrasting genotypes further supported the impact of heat stress and differentiated the response of HT and HS genotypes to varying temperatures. Our studies indicated that temperatures >35/25°C were highly detrimental for growth and yield in lentil. While HT genotypes tolerated temperatures up to 40/30°C by producing fewer pods, the HS genotypes failed to do so even at 38/28°C. The findings attributed heat tolerance to superior pollen function and higher expression of leaf antioxidants. PMID:28579994
Segner, Helmut; Verburg-van Kemenade, B M Lidy; Chadzinska, Magdalena
2017-01-01
The present review discusses the communication between the hypothalamic-pituitary-gonad (HPG) axis and the immune system of vertebrates, attempting to situate the HPG-immune interaction into the context of life history trade-offs between reproductive and immune functions. More specifically, (i) we review molecular and cellular interactions between hormones of the HPG axis, and, as far as known, the involved mechanisms on immune functions, (ii) we evaluate whether the HPG-immune crosstalk serves as proximate mechanism mediating reproductive-immune trade-offs, and (iii) we ask whether the nature of the HPG-immune interaction is conserved throughout vertebrate evolution, despite the changes in immune functions, reproductive modes, and life histories. In all vertebrate classes studied so far, HPG hormones have immunomodulatory functions, and indications exist that they contribute to reproduction-immunity resource trade-offs, although the very limited information available for most non-mammalian vertebrates makes it difficult to judge how comparable or different the interactions are. There is good evidence that the HPG-immune crosstalk is part of the proximate mechanisms underlying the reproductive-immune trade-offs of vertebrates, but it is only one factor in a complex network of factors and processes. The fact that the HPG-immune interaction is flexible and can adapt to the functional and physiological requirements of specific life histories. Moreover, the assumption of a relatively fixed pattern of HPG influence on immune functions, with, for example, androgens always leading to immunosuppression and estrogens always being immunoprotective, is probably oversimplified, but the HPG-immune interaction can vary depending on the physiological and envoironmental context. Finally, the HPG-immune interaction is not only driven by resource trade-offs, but additional factors such as, for instance, the evolution of viviparity shape this neuroendocrine-immune relationship. Copyright © 2016 Elsevier Ltd. All rights reserved.
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 reduces the functional diversity of tree assemblages in fragmented landscapes. PMID:17878943
Relaxin family peptides in the male reproductive system--a critical appraisal.
Ivell, Richard; Kotula-Balak, Malgorzata; Glynn, Danielle; Heng, Kee; Anand-Ivell, Ravinder
2011-02-01
The human genome project has identified, besides ovarian relaxin (RLN), six other relaxin-like molecules (RLN3, H1-RLN, INSL3-6), most of which appear to be expressed in the testis and/or male reproductive system, together with four different G-protein-coupled receptors responsive to one or other of these peptides. Earlier work on relaxin in the male assumed the simplistic hypothesis of only a single relaxin-like entity. This review systematically examines the expression and physiology of relaxin-like molecules in the male reproductive system in order to reappraise the importance of this hormone system for male reproductive function. Although there are important species differences, only INSL3 and INSL6 appear to be generally expressed at a moderately high level within the testis, whereas ovarian RLN is consistently a major secretory product of the prostate epithelium. However, all members of this relaxin-like family appear to be expressed also at a low level in different organs of the male reproductive system, suggesting possible autocrine/paracrine effects. The four receptors (RXFP1-4) for these peptides are also expressed to differing levels in both somatic and seminiferous compartments of the testis and in the prostate, supporting relevant functions for most members of this interesting peptide family. Recent studies of relaxin family peptides in prostate pathology highlight their functional importance in the clinical context as potential causative, diagnostic and therapeutic agents and warrant more specific and detailed studies of their roles also in regard to male fertility and other aspects of male reproductive function.
Triclocarban (TCC) is a widely used antimicrobial agent that is routinely detected in surface waters. The present study was designed to examine TCC’s efficacy and mode of action as a reproductive toxicant in fish. Reproductively mature Pimephales promelas were continuously ...
USDA-ARS?s Scientific Manuscript database
Age at puberty is a moderately heritable trait and an early indicator of sow reproductive longevity. Gilts that express first estrus early in life are characterized by improved reproductive longevity and lifetime productivity. These traits are dependent on the function of the hypothalamic-pituitary-...
USDA-ARS?s Scientific Manuscript database
Dominance rank in animal societies is correlated with changes in both reproductive physiology and behavior. In some social insects, dominance status is used to determine a reproductive division of labor, where a few colony members reproduce while most remain functionally sterile. Changes in reproduc...
2011-01-01
Background Cost of delivering reproductive health services to low-income populations will always require total or partial subsidization by the government and/or development partners. Broadly termed "Demand-Side Financing" or "Output-Based Aid", includes a range of interventions that channel government or donor subsidies to the service user rather than the service provider. Initial findings from the few assessments of reproductive health voucher-and-accreditation programs suggest that, if implemented well, these programs have great potential for achieving the policy objectives of increasing access and use, reducing inequities and enhancing program efficiency and service quality. At this point in time, however, there is a paucity of evidence describing how the various voucher programs function in different settings, for various reproductive health services. Methods/Design Population Council-Nairobi, funded by the Bill and Melinda Gates Foundation, intends to address the lack of evidence around the pros and cons of 'voucher and accreditation' approaches to improving the reproductive health of low income women in five developing countries. In Bangladesh, the activities will be conducted in 11 accredited health facilities where Demand Side Financing program is being implemented and compared with populations drawn from areas served by similar non-accredited facilities. Facility inventories, client exit interviews and service provider interviews will be used to collect comparable data across each facility for assessing readiness and quality of care. In-depth interviews with key stakeholders will be conducted to gain a deeper understanding about the program. A population-based survey will also be carried out in two types of locations: areas where vouchers are distributed and similar locations where vouchers are not distributed. Discussion This is a quasi-experimental study which will investigate the impact of the voucher approach on improving maternal health behaviors and status and reducing inequities at the population level. We expect a significant increase in the utilization of maternal health care services by the accredited health facilities in the experimental areas compared to the control areas as a direct result of the interventions. If the voucher scheme in Bangladesh is found effective, it may help other countries to adopt this approach for improving utilization of maternity care services for reducing maternal mortality. PMID:21513528
Rob, Ubaidur; Rahman, Moshiur; Bellows, Benjamin
2011-04-22
Cost of delivering reproductive health services to low-income populations will always require total or partial subsidization by the government and/or development partners. Broadly termed "Demand-Side Financing" or "Output-Based Aid", includes a range of interventions that channel government or donor subsidies to the service user rather than the service provider. Initial findings from the few assessments of reproductive health voucher-and-accreditation programs suggest that, if implemented well, these programs have great potential for achieving the policy objectives of increasing access and use, reducing inequities and enhancing program efficiency and service quality. At this point in time, however, there is a paucity of evidence describing how the various voucher programs function in different settings, for various reproductive health services. Population Council-Nairobi, funded by the Bill and Melinda Gates Foundation, intends to address the lack of evidence around the pros and cons of 'voucher and accreditation' approaches to improving the reproductive health of low income women in five developing countries. In Bangladesh, the activities will be conducted in 11 accredited health facilities where Demand Side Financing program is being implemented and compared with populations drawn from areas served by similar non-accredited facilities. Facility inventories, client exit interviews and service provider interviews will be used to collect comparable data across each facility for assessing readiness and quality of care. In-depth interviews with key stakeholders will be conducted to gain a deeper understanding about the program. A population-based survey will also be carried out in two types of locations: areas where vouchers are distributed and similar locations where vouchers are not distributed. This is a quasi-experimental study which will investigate the impact of the voucher approach on improving maternal health behaviors and status and reducing inequities at the population level. We expect a significant increase in the utilization of maternal health care services by the accredited health facilities in the experimental areas compared to the control areas as a direct result of the interventions. If the voucher scheme in Bangladesh is found effective, it may help other countries to adopt this approach for improving utilization of maternity care services for reducing maternal mortality.
Adipokines in human reproduction.
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.
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.
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.
Robotics in reproductive medicine.
Sroga, Julie; Patel, Sejal Dharia; Falcone, Tommaso
2008-01-01
In the past decade, robotic technology has been increasingly incorporated into various industries, including surgery and medicine. This chapter will review the history, development, current applications, and future of robotic technology in reproductive medicine. A literature search was performed for all publications regarding robotic technology in medicine, surgery, reproductive endocrinology, and its role in both surgical education and telepresence surgery. As robotic assisted surgery has emerged, this technology provides a feasible option for minimally invasive surgery, impacts surgical education, and plays a role in telepresence surgery.
Reproductive physiology of the male camelid.
Bravo, P W; Johnson, L W
1994-07-01
The physiology of reproduction with emphasis on endocrinology of llamas and alpacas is addressed. Information regarding male anatomy, puberty, testicular function, semen description, and sexual behavior is also included.
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.
Current versus future reproduction and longevity: a re-evaluation of predictions and mechanisms.
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.
Current versus future reproduction and longevity: a re-evaluation of predictions and mechanisms
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
Gender, sexual health and reproductive health promotion.
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.
Finocchario-Kessler, Sarah; Dariotis, Jacinda K.
2013-01-01
Provider-initiated conversations with people living with HIV about reproductive plans are lacking. Providers must know whether their patients want to bear children to tailor treatment and refer for HIV preconception counseling to help achieve patients’ reproductive goals while minimizing transmission to partners and children. The early focus on men who have sex with men largely excluded consideration of the epidemic’s impact on reproductive health. We used a historical review of the US epidemic to describe the problem’s scope and understand if this legacy underlies the current neglect of reproductive planning. Drawing on peer-reviewed literature, we discuss key themes relevant to assessing and understanding attention to desires for children among HIV-positive people. We conclude with recommendations for addressing persistent stigma and enhancing patient–provider communication about reproductive intentions. PMID:23763424
Impact of reproductive health on socio-economic development: a case study of Nigeria.
Adinma, J I B; Adinma, E D
2011-03-01
The link between reproductive health, sexual and reproductive right, and development was highlighted at the International Conference on Population and Development held in Egypt. Developmental disparities are related to socio-economic differences which have led to the identification of distinct socio-economic classifications of nations. Human development represents the socioeconomic standing of any nation, in addition to literacy status and life expectancy. Africa accounts for 25% of the world's landmass but remains the world's poorest continent. Nigeria, the most populous country in Africa, has policies and programmes geared towards the improvement of its socio-economic standing and overal development, with little positive result. Reproductive health is a panacea towards reversing the stalled socio-economic growth of Nigeria as evident from the linkage between reproductive health and development, highlighted in Millennium Development Goals 3, 4, 5 and 6. Fast tracking Nigeria's development requires implementation of reproductive health policies and programmes targeted on women and children.
Gnan, Sebastian; Marsh, Tom; Kover, Paula X
2017-01-01
Leaves are thought to be the primary carbon source for reproduction in plants, so a positive relationship between vegetative size and reproductive output is expected, establishing a trade-off between time to reproduction and reproductive output. A common response to higher temperatures due to climate changes is the induction of earlier transition into reproduction. Thus, in annual plants, earlier transition into flowering can potentially constrain plant size and reduce seed production. However, trade-offs between early reproduction and fitness are not always observed, suggesting mechanisms to escape the constraints of early flowering do exist. Here, we test whether inflorescence photosynthesis contribution to the reproductive output of Arabidopsis thaliana can offset the cost of early reproduction. We followed the development, growth rate and fitness of 15 accessions, and removed all rosette leaves at flowering (prior to the completion of inflorescence development or any fruit production) in half of the plants to determine the ability of inflorescences to maintain fitness in the absence of leaves. Although leaf removal significantly reduced fruit number, seed weight and plant height, even the most severely impacted accessions maintained 35% of their fitness with the inflorescence as the sole photosynthetic organ; and some accessions experienced no reduction in fitness. Differences between accessions in their ability to maintain fitness after leaf removal is best explained by earlier flowering time and the ability to maintain as many or more branches after leaf removal as in the control treatment. Although earlier flowering does constrain plant vegetative size, we found that inflorescence photosynthesis can significantly contribute to seed production, explaining why early flowering plants can maintain high fitness despite a reduction in vegetative size. Thus, plants can be released from the usually assumed trade-offs associated with earlier reproduction, and selection on inflorescence traits can mediate the impact of climate change on phenology.
Cotton, Leanne M.; O’Bryan, Moira K.; Hinton, Barry T.
2008-01-01
The major function of the reproductive system is to ensure the survival of the species by passing on hereditary traits from one generation to the next. This is accomplished through the production of gametes and the generation of hormones that function in the maturation and regulation of the reproductive system. It is well established that normal development and function of the male reproductive system is mediated by endocrine and paracrine signaling pathways. Fibroblast growth factors (FGFs), their receptors (FGFRs), and signaling cascades have been implicated in a diverse range of cellular processes including: proliferation, apoptosis, cell survival, chemotaxis, cell adhesion, motility, and differentiation. The maintenance and regulation of correct FGF signaling is evident from human and mouse genetic studies which demonstrate that mutations leading to disruption of FGF signaling cause a variety of developmental disorders including dominant skeletal diseases, infertility, and cancer. Over the course of this review, we will provide evidence for differential expression of FGFs/FGFRs in the testis, male germ cells, the epididymis, the seminal vesicle, and the prostate. We will show that this signaling cascade has an important role in sperm development and maturation. Furthermore, we will demonstrate that FGF/FGFR signaling is essential for normal epididymal function and prostate development. To this end, we will provide evidence for the involvement of the FGF signaling system in the regulation and maintenance of the male reproductive system. PMID:18216218
Cotton, Leanne M; O'Bryan, Moira K; Hinton, Barry T
2008-04-01
The major function of the reproductive system is to ensure the survival of the species by passing on hereditary traits from one generation to the next. This is accomplished through the production of gametes and the generation of hormones that function in the maturation and regulation of the reproductive system. It is well established that normal development and function of the male reproductive system is mediated by endocrine and paracrine signaling pathways. Fibroblast growth factors (FGFs), their receptors (FGFRs), and signaling cascades have been implicated in a diverse range of cellular processes including: proliferation, apoptosis, cell survival, chemotaxis, cell adhesion, motility, and differentiation. The maintenance and regulation of correct FGF signaling is evident from human and mouse genetic studies which demonstrate that mutations leading to disruption of FGF signaling cause a variety of developmental disorders including dominant skeletal diseases, infertility, and cancer. Over the course of this review, we will provide evidence for differential expression of FGFs/FGFRs in the testis, male germ cells, the epididymis, the seminal vesicle, and the prostate. We will show that this signaling cascade has an important role in sperm development and maturation. Furthermore, we will demonstrate that FGF/FGFR signaling is essential for normal epididymal function and prostate development. To this end, we will provide evidence for the involvement of the FGF signaling system in the regulation and maintenance of the male reproductive system.
[Mg2+]o/[Ca2+]o determines Ca2+ response at fertilization: tuning of adult phenotype?
Ozil, Jean-Pierre; Sainte-Beuve, Thierry; Banrezes, Bernadette
2017-11-01
Alteration of the postnatal phenotype has sparked great concern about the developmental impact of culture media used at fertilization. However, the mechanisms and compounds involved are yet to be determined. Here, we used the Ca 2+ responses from mouse eggs fertilized by ICSI as a dynamic and quantitative marker to understand the role of compounds in egg functioning and establish possible correlations with adult phenotypes. We computed 134 Ca 2+ responses from the first to the last oscillation in media with specific formulations. Analyses demonstrate that eggs generated two times as many Ca 2+ oscillations in KSOM as in M16 media (18.8 ± 7.0 vs 9.2 ± 2.5). Moreover, the time increment of the delay between two consecutive oscillations, named TIbO, is the most sensitive coefficient characterizing the mechanism that paces Ca 2+ oscillations once the egg has been fertilized. Neither doubling external free Ca 2+ nor dispermic fertilization increased significantly the total number of Ca 2+ oscillations. In contrast, removing Mg 2+ from the M16 boosted Ca 2+ oscillations to 54.0 ± 35.2. Hence, [Mg 2+ ] o /[Ca 2+ ] o appears to determine the number, duration and frequency of the Ca 2+ oscillations. These changes were correlated with long-term effects. The rate of female's growth was impacted with the 'KSOM' females having only half the fat deposit of 'M16' females. Moreover, adult animals issued from M16 had significantly smaller brain weight vs 'KSOM' and 'control' animals. TIbO is a new Ca 2+ coefficient that gauges the very early functional impact of culture media. It offers the possibility of establishing correlations with postnatal consequences according to IVF medium formulation.Free French abstract: A French translation of this abstract is freely available at http://www.reproduction-online.org/content/154/5/675/suppl/DC2. © 2017 Society for Reproduction and Fertility.
McGree, M.M.; Winkelman, D.L.; Vieira, N.K.M.; Vajda, A.M.
2010-01-01
Endocrine disrupting chemicals (EDCs) have been detected in surface waters worldwide and can lead to developmental and reproductive disruption in exposed fishes. In the US Great Plains, EDCs are impacting streams and rivers and may be causing adverse reproductive effects. To examine how estrogenic EDCs might affect reproductive success of plains fishes, we experimentally exposed male red shiners (Cyprinella lutrensis) to exogenous 17b-estradiol. We characterized the effects of estradiol on male gonadal histology and secondary sexual characteristics, determined whether exposure reduced reproductive success, and examined the effects of depuration. Adults were exposed to a mean concentration of 70 ng L-1 estradiol, a solvent control, or a water control for at least 83 days. Male exposure to estradiol resulted in elevated plasma vitellogenin concentrations, changes in spermatogenesis, reduced mating coloration and tubercles, altered mating behaviors, and reduced reproductive success with no viable progeny produced. Reproductive endpoints improved upon depuration (28 days). Exposure to estradiol had significant adverse effects on red shiners, indicating that wild populations may face developmental and reproductive difficulties if they are chronically exposed to estradiol.
Vitamin D is necessary for reproductive functions of the male rat.
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.
Role of pigment epithelium-derived factor in the reproductive system.
Chuderland, Dana; Ben-Ami, Ido; Bar-Joseph, Hadas; Shalgi, Ruth
2014-10-01
The physiological function of the female reproductive organs is hormonally controlled. In each cycle, the reproductive organs undergo tissue modifications that are accompanied by formation and destruction of blood vessels. Proper angiogenesis requires an accurate balance between stimulatory and inhibitory signals, provided by pro- and anti-angiogenic factors. As with many other tissues, vascular endothelial growth factor (VEGF) appears to be one of the major pro-angiogenic factors in the female reproductive organs. Pigment epithelium-derived factor (PEDF) is a non-inhibitory member of the serine protease inhibitors (serpin) superfamily, possessing potent physiologic anti-angiogenic activity that negates VEGF activity. The role of PEDF in decreasing abnormal neovascularization by exerting its anti-angiogenic effect that inhibits pro-angiogenic factors, including VEGF, has been investigated mainly in the eye and in cancer. This review summarizes the function of PEDF in the reproductive system, showing its hormonal regulation and its anti-angiogenic activity. Furthermore, some pathologies of the female reproductive organs, including endometriosis, ovarian hyperstimulation syndrome, polycystic ovary syndrome, and others, are associated with a faulty angiogenic process. This review illuminates the role of PEDF in their pathogenesis and treatment. Collectively, we can conclude that although PEDF seems to play an essential role in the physiology and pathophysiology of the reproductive system, its full role and mechanism of action still need to be elucidated. © 2014 Society for Reproduction and Fertility.
Infectious causes of reproductive disorders in cattle.
Yoo, Han Sang
2010-01-01
The incidences of reproductive disorders in bovine are increasing over years. This scenario is further aggravating due to more emphasis on selection and rearing of animal for specific commercial purposes which compromises livestock reproduction. Reproductive disorders like infertility and abortions in cattle are major problems in the bovine industry. The reproductive disorders might be caused by several different agents such as physical agents, chemical agents, biological agents, etc. Also, the causative agent and pathogenesis of reproductive disorders are influenced by various factors including environmental factor. The exact causes may not be evident and are often complicated with multiple causative agents. Thus, there is a need for multi-faceted approach to understand correlation of various factors with reproductive performance. Of the agents, infectious biological agents are significant cause of reproductive disorder and are of high priority in the bovine industry. These factors are not only related to the prosperity of bovine industry but are also important from public health point of view because of their zoonotic potentials. Several infectious agents like bacterial, viral, protozoon, chlamydial and fungal agents are known to have direct impact on reproductive health of cattle. These diseases can be arranged and discussed in different groups based on the causative agents.
Clarke, I J; Arbabi, L
2016-07-01
Gonadotropin releasing hormone is the primary driver of reproductive function and pulsatile GnRH secretion from the brain causes the synthesis and secretion of LH and FSH from the pituitary gland. Recent work has revealed that the secretion of GnRH is controlled at the level of the GnRH secretory terminals in the median eminence. At this level, projections of kisspeptin cells from the arcuate nucleus of the hypothalamus are seen to be closely associated with fibers and terminals of GnRH cells. Direct application of kisspeptin into the median eminence causes release of GnRH. The kisspeptin cells are activated at the time of a natural "pulse" secretion of GnRH, as reflected in the secretion of LH. This appears to be due to input to the kisspeptin cells from glutamatergic cells in the basal hypothalamus, indicating that more than 1 neural element is involved in the secretion of GnRH. Because the GnRH secretory terminals are outside the blood-brain barrier, factors such as kisspeptin may be administered systemically to cause GnRH secretion; this offers opportunities for manipulation of the reproductive axis using factors that do not cross the blood-brain barrier. In particular, kisspeptin or analogs of the same may be used to activate reproduction in the nonbreeding season of domestic animals. Another brain peptide that influences reproductive function is gonadotropin inhibitory hormone (GnIH). Work in sheep shows that this peptide acts on GnRH neuronal perikarya, but projections to the median eminence also allow secretion into the hypophysial portal blood and action of GnIH on pituitary gonadotropes. GnIH cells are upregulated in anestrus, and infusion of GnIH can block the ovulatory surge in GnRH and/or LH secretion. Metabolic status may also affect the secretion of reproduction, and this could involve action of gut peptides and leptin. Neuropeptide Y and Y-receptor ligands have a negative impact on reproduction, and Neuropeptide Y production is markedly increased in negative energy balance; this may be the cause of lowered GnRH and gonadotropin secretion in this state. There is a complex interaction between appetite-regulating peptide neurons and kisspeptin neurons that enables the former to regulate the latter both positively and negatively. In terms of how GnRH secretion is reduced during stress, recent data indicate that GnIH cells are integrally involved, with increased input to the GnRH cells. The secretion of GnIH into the portal blood is not increased during stress, so the negative effect is most likely effected at the level of GnRH neuronal cell bodies. Copyright © 2016 Elsevier Inc. All rights reserved.
Using expert opinion to prioritize impacts of climate change on sea turtles' nesting grounds.
Fuentes, M M P B; Cinner, J E
2010-12-01
Managers and conservationists often need to prioritize which impacts from climate change to deal with from a long list of threats. However, data which allows comparison of the relative impact from climatic threats for decision-making is often unavailable. This is the case for the management of sea turtles in the face of climate change. The terrestrial life stages of sea turtles can be negatively impacted by various climatic processes, such as sea level rise, altered cyclonic activity, and increased sand temperatures. However, no study has systematically investigated the relative impact of each of these climatic processes, making it challenging for managers to prioritize their decisions and resources. To address this we offer a systematic method for eliciting expert knowledge to estimate the relative impact of climatic processes on sea turtles' terrestrial reproductive phase. For this we used as an example the world's largest population of green sea turtles and asked 22 scientists and managers to answer a paper based survey with a series of pair-wise comparison matrices that compared the anticipated impacts from each climatic process. Both scientists and managers agreed that increased sand temperature will likely cause the most threat to the reproductive output of the nGBR green turtle population followed by sea level rise, then altered cyclonic activity. The methodology used proved useful to determine the relative impact of the selected climatic processes on sea turtles' reproductive output and provided valuable information for decision-making. Thus, the methodological approach can potentially be applied to other species and ecosystems of management concern. Copyright © 2009 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Guest, J. R.; Baird, A. H.; Goh, B. P. L.; Chou, L. M.
2012-09-01
The sexual system in corals refers to the spatial and temporal pattern of sexual function within an individual coral polyp, colony or population. Although information on sexual systems now exists for over 400 scleractinian species, data are still lacking for some important reef-building taxa. The vast majority of scleractinians are either simultaneous hermaphrodites or gonochoric with other sexual systems rarely occurring. Diploastrea heliopora is one of the most ubiquitous and easily recognised reef-building species in the Indo-West Pacific; however, surprisingly little is known about its reproductive biology. The aim of the present study was to examine the reproductive biology of D. heliopora colonies on chronically impacted, equatorial reefs south of Singapore. Here we show that in Singapore, D. heliopora is a broadcast spawner with predominantly gonochoric polyps. Colonies, however, contained male, female and a low proportion of cosexual polyps during the 14-month sampling period. The most plausible explanation for this is that polyps switch sexes with oogenic and spermatogenic cycles occasionally overlapping. This leads to colony level alternation of sex function within and between breeding seasons. While this sexual system is atypical for scleractinians, it supports molecular evidence that D. heliopora is phylogenetically distinct from species formerly in the family Faviidae.
Miller, Karen J; Gunasekera, Rasanthi M
2017-04-10
Ecological processes in the deep sea are poorly understood due to the logistical constraints of sampling thousands of metres below the ocean's surface and remote from most land masses. Under such circumstances, genetic data provides unparalleled insight into biological and ecological relationships. We use microsatellite DNA to compare the population structure, reproductive mode and dispersal capacity in two deep sea corals from seamounts in the Southern Ocean. The solitary coral Desmophyllum dianthus has widespread dispersal consistent with its global distribution and resilience to disturbance. In contrast, for the matrix-forming colonial coral Solenosmilia variabilis asexual reproduction is important and the dispersal of sexually produced larvae is negligible, resulting in isolated populations. Interestingly, despite the recognised impacts of fishing on seamount communities, genetic diversity on fished and unfished seamounts was similar for both species, suggesting that evolutionary resilience remains despite reductions in biomass. Our results provide empirical evidence that a group of seamounts can function either as isolated islands or stepping stones for dispersal for different taxa. Furthermore different strategies will be required to protect the two sympatric corals and consequently the recently declared marine reserves in this region may function as a network for D. dianthus, but not for S. variabilis.
NASA Astrophysics Data System (ADS)
Miller, Karen J.; Gunasekera, Rasanthi M.
2017-04-01
Ecological processes in the deep sea are poorly understood due to the logistical constraints of sampling thousands of metres below the ocean’s surface and remote from most land masses. Under such circumstances, genetic data provides unparalleled insight into biological and ecological relationships. We use microsatellite DNA to compare the population structure, reproductive mode and dispersal capacity in two deep sea corals from seamounts in the Southern Ocean. The solitary coral Desmophyllum dianthus has widespread dispersal consistent with its global distribution and resilience to disturbance. In contrast, for the matrix-forming colonial coral Solenosmilia variabilis asexual reproduction is important and the dispersal of sexually produced larvae is negligible, resulting in isolated populations. Interestingly, despite the recognised impacts of fishing on seamount communities, genetic diversity on fished and unfished seamounts was similar for both species, suggesting that evolutionary resilience remains despite reductions in biomass. Our results provide empirical evidence that a group of seamounts can function either as isolated islands or stepping stones for dispersal for different taxa. Furthermore different strategies will be required to protect the two sympatric corals and consequently the recently declared marine reserves in this region may function as a network for D. dianthus, but not for S. variabilis.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-01-14
... Reproductive Health Drugs and the Drug Safety and Risk Management Advisory Committee. General Function of the...] Joint Meeting of the Advisory Committee for Reproductive Health Drugs and the Drug Safety and Risk Management Advisory Committee; Notice of Meeting AGENCY: Food and Drug Administration, HHS. ACTION: Notice...
Federal Register 2010, 2011, 2012, 2013, 2014
2011-09-23
... Reproductive Health Drugs and the Drug Safety and Risk Management Advisory Committee. General Function of the...] Joint Meeting of the Advisory Committee for Reproductive Health Drugs and the Drug Safety and Risk Management Advisory Committee; Notice of Meeting AGENCY: Food and Drug Administration, HHS. ACTION: Notice...
Federal Register 2010, 2011, 2012, 2013, 2014
2011-09-23
... Reproductive Health Drugs and the Drug Safety and Risk Management Advisory Committee. General Function of the...] Joint Meeting of the Advisory Committee for Reproductive Health Drugs and the Drug Safety and Risk Management Advisory Committee; Notice of Meeting AGENCY: Food and Drug Administration, HHS. ACTION: Notice...
Federal Register 2010, 2011, 2012, 2013, 2014
2013-03-14
... Reproductive Health Drugs and the Drug Safety and Risk Management Advisory Committee. General Function of the...] Joint Meeting of the Advisory Committee for Reproductive Health Drugs and the Drug Safety and Risk Management Advisory Committee; Notice of Meeting AGENCY: Food and Drug Administration, HHS. ACTION: Notice...
USDA-ARS?s Scientific Manuscript database
The purpose of this study was to evaluate the effects of environmentally relevant dietary MeHg exposures on adult female yellow perch (Perca flavescens) and zebrafish (Danio rerio)reproduction. Yellow perch were used in the study for their socioeconomic and ecological importance within the Great Lak...
USDA-ARS?s Scientific Manuscript database
Genetic variants associated with traits such as age at puberty and litter size could provide insight into the underlying genetic sources of variation impacting sow reproductive longevity and productivity. Genomewide characterization and gene expression profiling were used using gilts from the Univer...
NASA Astrophysics Data System (ADS)
Calleri, Daniel V.; Rosengaus, Rebeca B.; Traniello, James F. A.
2005-06-01
To determine the impact of inbreeding and outbreeding on disease resistance and survival during colony foundation, nestmate (NM) and non-nestmate (NON) primary reproductives of the dampwood termite Zootermopsis angusticollis were exposed to a single or double dose of conidia of the entomopathogenic fungus Metarhizium anisopliae. Male and female primary reproductive pairs originating from the same parent colony had higher survivorship than NON pairs in control and conidia-exposure treatments. The survival advantage of NM primary reproductives increased with the intensity of pathogen challenge and was significantly greater in the single- and double-dose treatments than in the controls. Although NM pairs had significantly lower mortality than NON pairs, the survivorship of colonies stabilized as they matured and inbred and outbred colonies did not differ in offspring production. These results demonstrate that colony foundation by NON male and female reproductives may have a disease-related survival cost during this critical phase of their life cycle. There may also be a cost associated with lower offspring heterozygosity, but in the first generation this does not appear to significantly impact colony growth.
Aracena-Genao, Belkis; del Río-Zolezzi, Aurora
2016-01-01
Objective To analyze whether the changes observed in the level and distribution of resources for maternal health and family planning (MHFP) programs from 2003 to 2012 were consistent with the financial goals of the related policies. Materials and Methods A longitudinal descriptive analysis of the Mexican Reproductive Health Subaccounts 2003–2012 was performed by financing scheme and health function. Financing schemes included social security, government schemes, household out-of-pocket (OOP) payments, and private insurance plans. Functions were preventive care, including family planning, antenatal and puerperium health services, normal and cesarean deliveries, and treatment of complications. Changes in the financial imbalance indicators covered by MHFP policy were tracked: (a) public and OOP expenditures as percentages of total MHFP spending; (b) public expenditure per woman of reproductive age (WoRA, 15–49 years) by financing scheme; (c) public expenditure on treating complications as a percentage of preventive care; and (d) public expenditure on WoRA at state level. Statistical analyses of trends and distributions were performed. Results Public expenditure on government schemes grew by approximately 300%, and the financial imbalance between populations covered by social security and government schemes decreased. The financial burden on households declined, particularly among households without social security. Expenditure on preventive care grew by 16%, narrowing the financing gap between treatment of complications and preventive care. Finally, public expenditure per WoRA for government schemes nearly doubled at the state level, although considerable disparities persist. Conclusions Changes in the level and distribution of MHFP funding from 2003 to 2012 were consistent with the relevant policy goals. However, improving efficiency requires further analysis to ascertain the impact of investments on health outcomes. This, in turn, will require better financial data systems as a precondition for improving the monitoring and accountability functions in Mexico. PMID:26812646
Multiple molecular effect pathways of an environmental oestrogen in fish.
Filby, Amy L; Thorpe, Karen L; Tyler, Charles R
2006-08-01
Complex interrelationships in the signalling of oestrogenic effects mean that environmental oestrogens present in the aquatic environment have the potential to disrupt physiological function in fish in a more complex manner than portrayed in the present literature. Taking a broader approach to investigate the possible effect pathways and the likely consequences of environmental oestrogen exposure in fish, the effects of 17beta-oestradiol (E(2)) were studied on the expression of a suite of genes which interact to mediate growth, development and thyroid and interrenal function (growth hormone GH (gh), GH receptor (ghr ), insulin-like growth factor (IGF-I) (igf1), IGF-I receptor (igf1r ), thyroid hormone receptors-alpha (thra) and -beta (thrb) and glucocorticoid receptor (gr )) together with the expression analyses of sex-steroid receptors and ten other genes centrally involved in sexual development and reproduction in fathead minnow (fhm; Pimephales promelas). Exposure of adult fhm to 35 ng E(2)/l for 14 days induced classic oestrogen biomarker responses (hepatic oestrogen receptor 1 and plasma vitellogenin), and impacted on the reproductive axis, feminising "male" steroidogenic enzyme expression profiles and suppressing genes involved in testis differentiation. However, E(2) also triggered a cascade of responses for gh, ghr, igf1, igf1r, thra, thrb and gr in the pituitary, brain, liver, gonad and gill, with potential consequences for the functioning of many physiological processes, not just reproduction. Molecular responses to E(2) were complex, with most genes showing differential responses between tissues and sexes. For example, igf1 expression increased in brain but decreased in gill on exposure to E(2), and responded in an opposite way in males compared with females in liver, gonad and pituitary. These findings demonstrate the importance of developing a deeper understanding of the endocrine interactions for unravelling the mechanisms of environmental oestrogen action and predicting the likely health consequences.
The effects of radiofrequency electromagnetic radiation on sperm function.
Houston, B J; Nixon, B; King, B V; De Iuliis, G N; Aitken, R J
2016-12-01
Mobile phone usage has become an integral part of our lives. However, the effects of the radiofrequency electromagnetic radiation (RF-EMR) emitted by these devices on biological systems and specifically the reproductive systems are currently under active debate. A fundamental hindrance to the current debate is that there is no clear mechanism of how such non-ionising radiation influences biological systems. Therefore, we explored the documented impacts of RF-EMR on the male reproductive system and considered any common observations that could provide insights on a potential mechanism. Among a total of 27 studies investigating the effects of RF-EMR on the male reproductive system, negative consequences of exposure were reported in 21. Within these 21 studies, 11 of the 15 that investigated sperm motility reported significant declines, 7 of 7 that measured the production of reactive oxygen species (ROS) documented elevated levels and 4 of 5 studies that probed for DNA damage highlighted increased damage due to RF-EMR exposure. Associated with this, RF-EMR treatment reduced the antioxidant levels in 6 of 6 studies that discussed this phenomenon, whereas consequences of RF-EMR were successfully ameliorated with the supplementation of antioxidants in all 3 studies that carried out these experiments. In light of this, we envisage a two-step mechanism whereby RF-EMR is able to induce mitochondrial dysfunction leading to elevated ROS production. A continued focus on research, which aims to shed light on the biological effects of RF-EMR will allow us to test and assess this proposed mechanism in a variety of cell types. © 2016 Society for Reproduction and Fertility.
NASA Astrophysics Data System (ADS)
Ajemian, M. J.; Wetz, J. J.; Brewton, R. A.; Downey, C. H.; Stunz, G. W.
2016-02-01
Energy exploration in the Gulf of Mexico (Gulf) has resulted in the addition of numerous oil and gas production rigs that have added structurally complex habitat to an area otherwise dominated by bare bottom. The impact of these artificial structures on fish populations is largely unknown and there is ongoing debate about their functionality. Red Snapper (Lutjanus campechanus), an ecologically and economically important sportfish to the region, use natural as well as the artificial reefs created by standing and reefed (toppled or cutoff) oil and gas rigs. However, little is known about how trophic and reproductive characteristics of Red Snapper vary over these multiple habitat types. We analyzed stable isotopic composition (δ13C, δ 15N) of epaxial muscle and compared reproductive potential of Red Snapper (155-855 mm TL) from standing rigs, reefed rigs, and natural hard-bottom habitats off Texas. Red Snapper from standing rig sites were isotopically enriched in δ 15N compared to lower relief habitats, suggesting they were feeding at a higher trophic level on standing rigs. While gonadosomatic indices (GSI) and comparative histology implied a similar spawning season among structure types, GSI was highest for both sexes at standing rigs. These initial results suggest that while standing rigs appear to provide more enriched food resources leading to higher Red Snapper reproductive capacity, the productivity of this species is similar between currently permitted rig decommissioning options (i.e., cutoff and toppled rigs) and natural hard-bottom habitats in the Gulf of Mexico.
Branching habit and the allocation of reproductive resources in conifers.
Leslie, Andrew B
2012-09-01
Correlated relationships between branch thickness, branch density, and twig and leaf size have been used extensively to study the evolution of plant canopy architecture, but fewer studies have explored the impact of these relationships on the allocation of reproductive resources. This study quantifies pollen cone production in conifers, which have similar basic reproductive biology but vary dramatically in branching habit, in order to test how differences in branch diameter influence pollen cone size and the density with which they are deployed in the canopy. Measurements of canopy branch density, the number of cones per branch and cone size were used to estimate the amount of pollen cone tissues produced by 16 species in three major conifer clades. The number of pollen grains produced was also estimated using direct counts from individual pollen cones. The total amount of pollen cone tissues in the conifer canopy varied little among species and clades, although vegetative traits such as branch thickness, branch density and pollen cone size varied over several orders of magnitude. However, branching habit controls the way these tissues are deployed: taxa with small branches produce small pollen cones at a high density, while taxa with large branches produce large cones relatively sparsely. Conifers appear to invest similar amounts of energy in pollen production independent of branching habit. However, similar associations between branch thickness, branch density and pollen cone size are seen across conifers, including members of living and extinct groups not directly studied here. This suggests that reproductive features relating to pollen cone size are in large part a function of the evolution of vegetative morphology and branching habit.
Nguyen, Philip V; Kafka, Jessica K; Ferreira, Victor H; Roth, Kristy; Kaushic, Charu
2014-01-01
The male and female reproductive tracts are complex microenvironments that have diverse functional demands. The immune system in the reproductive tract has the demanding task of providing a protective environment for a fetal allograft while simultaneously conferring protection against potential pathogens. As such, it has evolved a unique set of adaptations, primarily under the influence of sex hormones, which make it distinct from other mucosal sites. Here, we discuss the various components of the immune system that are present in both the male and female reproductive tracts, including innate soluble factors and cells and humoral and cell-mediated adaptive immunity under homeostatic conditions. We review the evidence showing unique phenotypic and functional characteristics of immune cells and responses in the male and female reproductive tracts that exhibit compartmentalization from systemic immunity and discuss how these features are influenced by sex hormones. We also examine the interactions among the reproductive tract, sex hormones and immune responses following HIV-1 infection. An improved understanding of the unique characteristics of the male and female reproductive tracts will provide insights into improving clinical treatments of the immunological causes of infertility and the design of prophylactic interventions for the prevention of sexually transmitted infections. PMID:24976268
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.
Introduction to Reproduction: Online Education for the Millennial Learner.
Castle, Megan; Kick, Laura; Haseley, Heather; Wallach, Harlan; Woodruff, Teresa K
2016-07-01
Despite staggering rates of sexually transmitted infections and unplanned pregnancies, reproductive health education is not yet standardized across secondary or postsecondary curricula. The Women's Health Research Institute and Northwestern University Information Technology created Introduction to Reproduction, a massive open online course to encourage global students to learn the biological foundations of reproductive health. This digital education experience appeals to the Millennial learner and offers unique opportunities to explore topics in reproductive biology via lectures, animations, and three-dimensional anatomical illustrations. Data were collected anonymously from de-identified learners who elected to self-report on their experiences while completing the course as well as through Coursera datasets. Northwestern University's Institutional Review Board classified this research project as an exempt status due to the de-identified nature of the collected data. Participants from 47 countries report on reproductive health content knowledge, past reproductive health education, and level of engagement with the topic. These data indicate that the Introduction to Reproduction course has a meaningful impact on its participants and presents the information in a concise and accessible format. Distribution of this course to a wider audience is the goal for the program and important to the field of reproductive health. © 2016 by the Society for the Study of Reproduction, Inc.
Vinson, C C; Kanashiro, M; Harris, S A; Boshier, D H
2015-01-01
Selective logging in Brazil allows for the removal of up to 90% of trees above 50 cm diameter of a given timber species, independent of a species' life history characteristics or how quickly it will recover. The genetic and demographic effects of selective logging on two Amazonian timber species (Dipteryx odorata Leguminosae, Jacaranda copaia Bignoniaceae) with contrasting ecological and reproductive characteristics were assessed in the same forest. Genetic diversity and gene flow were characterized by genotyping adults and seed sampled before and after logging, using hypervariable microsatellite markers. Overall, there were no short-term genetic impacts on the J. copaia population, with commercial application of current Brazilian forest management regulations. In contrast, for D. Odorata, selective logging showed a range of genetic impacts, with a 10% loss of alleles, and reductions in siring by pollen from trees within the 546-ha study area (23-11%) and in the number of pollen donors per progeny array (2.8-1.6), illustrating the importance of the surrounding landscape. Asynchrony in flowering between D. odorata trees led to trees with no breeding partners, which could limit the species reproduction and regeneration under current regulations. The results are summarized with other published studies from the same site and the implications for forest management discussed. The different types and levels of impacts associated with each species support the idea that ecological and genetic information by species, ecological guild or reproductive group is essential in helping to derive sustainable logging guidelines for tropical forests. © 2014 John Wiley & Sons Ltd.
Physiological Response and Habituation of Endangered Species to Military Training Activities
2009-11-01
Wasser. 2008. Long-term impacts of poaching on relatedness, stress physiology, and reproductive output of adult female African elephants . Conservation...Statistical analyses................................................................................................................ 19 Study 6: Impact of...Study 6: Impact of radio transmitters on northern cardinal parental investment and productivity
Linton, Danielle M; Macdonald, David W
2018-04-10
Climate is known to influence breeding phenology and reproductive success in temperate-zone bats, but long-term population level studies and interspecific comparisons are rare. Investigating the extent to which intrinsic (i.e. age), and extrinsic (i.e. spring weather conditions), factors influence such key demographic parameters as the proportion of females becoming pregnant, or completing lactation, each breeding season, is vital to understanding of bat population ecology and life-history traits. Using data from 12 breeding seasons (2006-2017), encompassing the reproductive histories of 623 Myotis daubentonii and 436 Myotis nattereri adult females, we compare rates of recruitment to the breeding population and show that these species differ in their relative sensitivity to environmental conditions and climatic variation, affecting annual reproductive success at the population level. We demonstrate that (1) spring weather conditions influence breeding phenology, with warm, dry and calm conditions leading to earlier parturition dates and advanced juvenile development, whilst cold, wet and windy weather delays birth timing and juvenile growth; (2) reproductive rates in first-year females are influenced by spring weather conditions in that breeding season and in the preceding breeding season when each cohort was born. Pregnancy and lactation rates were both higher when favourable spring foraging conditions were more prevalent; (3) reproductive success increases with age in both species, but at different rates; (4) reproductive rates were consistently higher, and showed less interannual variation, in second-year and older M. daubentonii (mean 91.55% ± 0.05 SD) than M. nattereri (mean 72.74% ± 0.15 SD); (5) estimates of reproductive success at the population level were highly correlated with the size of the juvenile cohort recorded each breeding season. Improving understanding of the influence of environmental conditions, especially extreme climatic fluctuations, and the identification of critical periods (i.e. spring for reproductive female bats in temperate zones), which have disproportionate and lasting impacts on breeding phenology and reproductive success at a population level, is critical for improving predictions of the likely impact of climate change on bat populations. © 2018 The Authors. Journal of Animal Ecology © 2018 British Ecological Society.
Intermittent metabolic switching, neuroplasticity and brain health
Mattson, Mark P.; Moehl, Keelin; Ghena, Nathaniel; Schmaedick, Maggie; Cheng, Aiwu
2018-01-01
During evolution, individuals whose brains and bodies functioned well in a fasted state were successful in acquiring food, enabling their survival and reproduction. With fasting and extended exercise, liver glycogen stores are depleted and ketones are produced from adipose-cell-derived fatty acids. This metabolic switch in cellular fuel source is accompanied by cellular and molecular adaptations of neural networks in the brain that enhance their functionality and bolster their resistance to stress, injury and disease. Here, we consider how intermittent metabolic switching, repeating cycles of a metabolic challenge that induces ketosis (fasting and/or exercise) followed by a recovery period (eating, resting and sleeping), may optimize brain function and resilience throughout the lifespan, with a focus on the neuronal circuits involved in cognition and mood. Such metabolic switching impacts multiple signalling pathways that promote neuroplasticity and resistance of the brain to injury and disease. PMID:29321682
Assisted reproductive technology (ART) in humans: facts and uncertainties.
Ménézo, Y J; Veiga, A; Pouly, J L
2000-01-15
Since the first in vitro fertilization (IVF) in human, the number of patients using Assisted Reproductive Technologies (ART) has increased tremendously. ART technologies have increased in number and their spectrum has also widened. The first IVF babies are now more than 20 years old. All the retrospective analyses have demonstrated that the obstetrical and pediatrical impact has not really affected single births. The main problems observed occur with multiple pregnancies, including high costs for the couples and for society. The decrease in the number of embryos transferred has improved the situation and moreover does not impair the final results. IntraCytoplasmic Sperm Injection (ICSI) is a more debatable and questionable technique with a real negative genetic impact. The main problem is chromosome abnormalities more specifically related to the sex chromosomes. The question of a systematic genetic work-up on the patients entering ICSI programs is discussed. No negative impact of cryopreservation has been demonstrated even though some controversy arises from time to time. Pre-implantation Genetic Diagnosis (PGD) is now a interesting tool for patients carrying genetic defects. Blastocyst biopsy now has a future role in reproductive medicine. Gender selection through sperm sorting is also now a reality. As with the other developing bio-technologies related to reproduction, there are ethical questions. The decisions concerning these technologies do not belong solely to scientists but are rather a matter for society to decide.
Inokuchi, Ayako; Yamamoto, Ryoko; Morita, Fumiyo; Takumi, Shota; Matsusaki, Hiromi; Ishibashi, Hiroshi; Tominaga, Nobuaki; Arizono, Koji
2015-09-01
Lithium (Li) has been widely used to treat bipolar disorder, and industrial use of Li has been increasing; thus, environmental pollution and ecological impacts of Li have become a concern. This study was conducted to clarify the potential biological effects of LiCl and Li(2)CO(3) on a nematode, Caenorhabditis elegans as a model system for evaluating soil contaminated with Li. Exposure of C. elegans to LiCl and Li(2)CO(3) decreased growth/maturation and reproduction. The lowest observed effect concentrations for growth, maturation and reproduction were 1250, 313 and 10 000 µm, respectively, for LiCl and 750, 750 and 3000 µm, respectively, for Li(2)CO(3). We also investigated the physiological function of LiCl and LiCO(3) in C. elegans using DNA microarray analysis as an eco-toxicogenomic approach. Among approximately 300 unique genes, including metabolic genes, the exposure to 78 µm LiCl downregulated the expression of 36 cytochrome P450, 16 ABC transporter, 10 glutathione S-transferase, 16 lipid metabolism and two vitellogenin genes. On the other hand, exposure to 375 µm Li(2)CO(3) downregulated the expression of 11 cytochrome P450, 13 ABC transporter, 13 lipid metabolism and one vitellogenin genes. No gene was upregulated by LiCl or Li(2)CO(3). These results suggest that LiCl and Li(2)CO(3) potentially affect the biological and physiological function in C. elegans associated with alteration of the gene expression such as metabolic genes. Our data also provide experimental support for the utility of toxicogenomics by integrating gene expression profiling into a toxicological study of an environmentally important organism such as C. elegans. Copyright © 2015 John Wiley & Sons, Ltd.
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.
Darwin's legacy: the forms, function and sexual diversity of flowers
Barrett, Spencer C. H.
2010-01-01
Charles Darwin studied floral biology for over 40 years and wrote three major books on plant reproduction. These works have provided the conceptual foundation for understanding floral adaptations that promote cross-fertilization and the mechanisms responsible for evolutionary transitions in reproductive systems. Many of Darwin's insights, gained from careful observations and experiments on diverse angiosperm species, remain remarkably durable today and have stimulated much current research on floral function and the evolution of mating systems. Here I review Darwin's seminal contributions to reproductive biology and provide an overview of the current status of research on several of the main topics to which he devoted considerable effort, including the consequences to fitness of cross- versus self-fertilization, the evolution and function of stylar polymorphisms, the adaptive significance of heteranthery, the origins of dioecy and related gender polymorphisms, and the transition from animal pollination to wind pollination. Post-Darwinian perspectives on floral function now recognize the importance of pollen dispersal and male outcrossed siring success in shaping floral adaptation. This has helped to link work on pollination biology and mating systems, two subfields of reproductive biology that remained largely isolated during much of the twentieth century despite Darwin's efforts towards integration. PMID:20047864
To feed or to breed: morphological constraints of mouthbrooding in coral reef cardinalfishes
Hoey, Andrew S.; Bellwood, David R.; Barnett, Adam
2012-01-01
Functionally coupled biomechanical systems are widespread in nature and are viewed as major constraints on evolutionary diversification, yet there have been few attempts to explore the implications of performing multiple functions within a single anatomical structure. Paternally mouthbrooding cardinalfishes present an ideal system to investigate the constraints of functional coupling as the oral jaws of male fishes are directly responsible for both feeding and reproductive functions. To test the effects of (i) mouthbrooding on feeding and (ii) feeding on reproductive potential we compared the feeding apparatus between sexes of nine species of cardinalfish and compared brood characteristics among species from different trophic groups, respectively. Mouthbrooding was strongly associated with the morphology of the feeding apparatus in males. Male cardinalfishes possessed longer heads, snouts and jaws than female conspecifics irrespective of body size, trophic group or evolutionary history. Conversely, reproductive potential also appeared to be related to trophic morphology. Piscivorous cardinalfishes produced larger, but fewer eggs, and had smaller brood volumes than species from the two invertebrate feeding groups. These interrelationships suggest that feeding and reproduction in the mouth of cardinalfishes may be tightly coupled. If so this may, in part, have contributed to the limited morphological diversification exhibited by cardinalfishes. PMID:22319124
To feed or to breed: morphological constraints of mouthbrooding in coral reef cardinalfishes.
Hoey, Andrew S; Bellwood, David R; Barnett, Adam
2012-06-22
Functionally coupled biomechanical systems are widespread in nature and are viewed as major constraints on evolutionary diversification, yet there have been few attempts to explore the implications of performing multiple functions within a single anatomical structure. Paternally mouthbrooding cardinalfishes present an ideal system to investigate the constraints of functional coupling as the oral jaws of male fishes are directly responsible for both feeding and reproductive functions. To test the effects of (i) mouthbrooding on feeding and (ii) feeding on reproductive potential we compared the feeding apparatus between sexes of nine species of cardinalfish and compared brood characteristics among species from different trophic groups, respectively. Mouthbrooding was strongly associated with the morphology of the feeding apparatus in males. Male cardinalfishes possessed longer heads, snouts and jaws than female conspecifics irrespective of body size, trophic group or evolutionary history. Conversely, reproductive potential also appeared to be related to trophic morphology. Piscivorous cardinalfishes produced larger, but fewer eggs, and had smaller brood volumes than species from the two invertebrate feeding groups. These interrelationships suggest that feeding and reproduction in the mouth of cardinalfishes may be tightly coupled. If so this may, in part, have contributed to the limited morphological diversification exhibited by cardinalfishes.
Novo, M; Verdú, I; Trigo, D; Martínez-Guitarte, J L
2018-04-15
Xenobiotics such as bisphenol A (BPA), are present in biosolids, which are applied as organic fertilizers in agricultural fields. Their effects on soil life have been poorly assessed, and this is particularly important in the case of earthworms, which represent the main animal biomass in this medium. In the present work we study the impacts of BPA on gene expression of Eisenia fetida, a widely used ecotoxicological model. Chronic soil tests and acute contact tests were performed, and gene expression was analyzed in total tissue and in masculine reproductive organs of the earthworms. The genes studied in this research played a role in endocrine pathways, detoxification mechanisms, stress response, epigenetics, and genotoxicity. Most of the genes were identified for the first time, providing potentially useful biomarkers for future assessments. For chronic exposures, no changes were detected in whole-body tissue; however, masculine reproductive organs showed changes in the expression of genes related to endocrine function (EcR, MAPR, AdipoR), epigenetic mechanisms (DNMTs), genotoxicity (PARP1), and stress responses (HSC70 4). For acute exposures, the expression of one epigenetic-related gene was altered for both whole-body tissues and male reproductive organs (Piwi2). Further changes were detected for whole-body tissues involved in detoxification (Metallothionein), stress (HSC70 4), and genotoxicity (PARP1) mechanisms. Acute exposure effects were also tested in whole-body tissues of juveniles, showing changes in the expression of Metallothionein and Piwi2. The molecular changes found in the analyzed earthworms indicate that exposure to BPA may have negative implications in their populations. Particularly interesting are the alterations related to epigenetic mechanisms, which suggest that future generations may be impacted. This study is the first to evaluate the molecular effects of BPA on soil organisms, and further assays will be necessary to better characterize the true environmental repercussions. Levels of gene expression in total-body tissues and masculine reproductive organs were analyzed in earthworms after exposure to bisphenol A and we observed associated changes in detoxification, endocrine, epigenetic, genotoxic and stress pathways. Copyright © 2017 Elsevier Inc. All rights reserved.
Genetic Evidence Highlights Potential Impacts of By-Catch to Cetaceans
Mendez, Martin; Rosenbaum, Howard C.; Wells, Randall S.; Stamper, Andrew; Bordino, Pablo
2010-01-01
Incidental entanglement in fishing gear is arguably the most serious threat to many populations of small cetaceans, judging by the alarming number of captured animals. However, other aspects of this threat, such as the potential capture of mother-offspring pairs or reproductive pairs, could be equally or even more significant but have rarely been evaluated. Using a combination of demographic and genetic data we provide evidence that i) Franciscana dolphin pairs that are potentially reproductive and mother-offspring pairs form temporal bonds, and ii) are entangled simultaneously. Our results highlight potential demographic and genetic impacts of by-catch to cetacean populations: the joint entanglement of mother-offspring or reproductive pairs, compared to random individuals, might exacerbate the demographic consequences of by-catch, and the loss of groups of relatives means that significant components of genetic diversity could be lost together. Given the social nature of many odontocetes (toothed cetaceans), we suggest that these potential impacts could be rather general to the group and therefore by-catch could be more detrimental than previously considered. PMID:21179542