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Potential Role of Zinc in the COVID-19 Disease Process and its Probable Impact on Reproduction.
Sethuram, R, Bai, D, Abu-Soud, HM
Reproductive sciences (Thousand Oaks, Calif.). 2022;(1):1-6
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Abstract
COVID-19 (coronavirus disease 2019) is the current world health crisis, producing extensive morbidity and mortality across all age groups. Given the established roles of zinc in combating oxidative damage and viral infections, zinc is being trialed as a treatment modality against COVID-19. Zinc also has confirmed roles in both male and female reproduction. The possible depletion of zinc with the oxidative events of COVID-19 is especially relevant to the fertility of affected couples. This review aims to present the pathophysiology of COVID-19, especially in relation to reproductive function; the role of zinc in the COVID-19 disease process; and how zinc depletion in concert with cytokine storm and reactive oxygen species production could affect reproduction. It also highlights research areas to better the understanding of COVID-19 and its impact on fertility and potential ways to mitigate the impact.
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Per- and poly-fluoroalkyl substances (PFAS) and female reproductive outcomes: PFAS elimination, endocrine-mediated effects, and disease.
Rickard, BP, Rizvi, I, Fenton, SE
Toxicology. 2022;:153031
Abstract
Per- and poly-fluoroalkyl substances (PFAS) are widespread environmental contaminants frequently detected in drinking water supplies worldwide that have been linked to a variety of adverse reproductive health outcomes in women. Compared to men, reproductive health effects in women are generally understudied while global trends in female reproduction rates are declining. Many factors may contribute to the observed decline in female reproduction, one of which is environmental contaminant exposure. PFAS have been used in home, food storage, personal care and industrial products for decades. Despite the phase-out of some legacy PFAS due to their environmental persistence and adverse health effects, alternative, short-chain and legacy PFAS mixtures will continue to pollute water and air and adversely influence women's health. Studies have shown that both long- and short-chain PFAS disrupt normal reproductive function in women through altering hormone secretion, menstrual cyclicity, and fertility. Here, we summarize the role of a variety of PFAS and PFAS mixtures in female reproductive tract dysfunction and disease. Since these chemicals may affect reproductive tissues directly or indirectly through endocrine disruption, the role of PFAS in breast, thyroid, and hypothalamic-pituitary-gonadal axis function are also discussed as the interplay between these tissues may be critical in understanding the long-term reproductive health effects of PFAS in women. A major research gap is the need for mechanism of action data - the targets for PFAS in the female reproductive and endocrine systems are not evident, but the effects are many. Given the global decline in female fecundity and the ability of PFAS to negatively impact female reproductive health, further studies are needed to examine effects on endocrine target tissues involved in the onset of reproductive disorders of women.
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Role for Selenium in Metabolic Homeostasis and Human Reproduction.
Mojadadi, A, Au, A, Salah, W, Witting, P, Ahmad, G
Nutrients. 2021;(9)
Abstract
Selenium (Se) is a micronutrient essential for life. Dietary intake of Se within the physiological range is critical for human health and reproductive functions. Selenium levels outside the recommended range have been implicated in infertility and variety of other human diseases. However, presently it is not clear how different dietary Se sources are processed in our bodies, and in which form or how much dietary Se is optimum to maintain metabolic homeostasis and boost reproductive health. This uncertainty leads to imprecision in published dietary guidelines and advice for human daily intake of Se and in some cases generating controversies and even adverse outcomes including mortality. The chief aim for this review is to describe the sources of organic and inorganic Se, the metabolic pathways of selenoproteins synthesis, and the critical role of selenprotenis in the thyroid gland homeostasis and reproductive/fertility functions. Controversies on the use of Se in clinical practice and future directions to address these challenges are also described and discussed herein.
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4.
The impact of stress combination on reproductive processes in crops.
Sinha, R, Fritschi, FB, Zandalinas, SI, Mittler, R
Plant science : an international journal of experimental plant biology. 2021;:111007
Abstract
Historically, extended droughts combined with heat waves caused severe reductions in crop yields estimated at billions of dollars annually. Because global warming and climate change are driving an increase in the frequency and intensity of combined water-deficit and heat stress episodes, understanding how these episodes impact yield is critical for our efforts to develop climate change-resilient crops. Recent studies demonstrated that a combination of water-deficit and heat stress exacerbates the impacts of water-deficit or heat stress on reproductive processes of different cereals and legumes, directly impacting grain production. These studies identified several different mechanisms potentially underlying the effects of stress combination on anthers, pollen, and stigma development and function, as well as fertilization. Here we review some of these findings focusing on unbalanced reactive oxygen accumulation, altered sugar concentrations, and conflicting functions of different hormones, as contributing to the reduction in yield during a combination of water-deficit and heat stress. Future studies focused on the effects of water-deficit and heat stress combination on reproduction of different crops are likely to unravel additional mechanisms, as well as reveal novel ways to develop stress combination-resilient crops. These could mitigate some of the potentially devastating impacts of this stress combination on agriculture.
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The Case for an Estrogen-iron Axis in Health and Disease.
Hamad, M, Bajbouj, K, Taneera, J
Experimental and clinical endocrinology & diabetes : official journal, German Society of Endocrinology [and] German Diabetes Association. 2020;(4):270-277
Abstract
Clinical and experimental evidence suggest that estrogen manipulates intracellular iron metabolism and that elevated levels of estrogen associate with increased systemic iron availability. This has been attributed to the ability of estrogen to suppress hepcidin synthesis, maintain ferroportin integrity and enhance iron release from iron-absorbing duodenal enterocytes and iron-storing macrophages and hepatocytes. These observations speak of a potential "estrogen-iron" axis that manipulates iron metabolism in response to hematologic (erythropoiesis) and non-hematologic (uterine growth, pregnancy, lactation) needs for iron. Such an axis could contribute to minimizing iron deficiency in premenopausal women and iron overload in postmenopausal women. It could also exacerbate iron overload and related clinical consequences including cancer, osteoporosis, cardiovascular complications and neurodegenerative symptoms, especially in postmenopausal women on hormonal replacement therapy. Understanding the role of estrogen in iron metabolism may shed some light on the pleotropic, but often paradoxical, roles of estrogen in human health and disease.
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6.
Human reproductive behavior, life history, and the Challenge Hypothesis: A 30-year review, retrospective and future directions.
Gray, PB, Straftis, AA, Bird, BM, McHale, TS, Zilioli, S
Hormones and behavior. 2020;:104530
Abstract
The Challenge Hypothesis (Wingfield et al., 1990) originally focused on adult male avian testosterone elevated in response to same-sex competition in reproductive contexts. The purpose of the present paper is to demonstrate how the Challenge Hypothesis has shaped ideas about human life histories. We conduct a citation analysis, drawing upon 400 Google Scholar citations in the human literature to identify patterns in this body of scholarship. We cover key factors, such as context and personality traits, that help explain variable testosterone responses such as winning/losing to adult competitive behavior. Findings from studies on courtship and sexual behavior indicate some variation in testosterone responses depending on factors such as motivation. A large body of research indicates that male testosterone levels are often lower in contexts of long-term committed partnerships and nurturant fathering and aligned with variation in male mating and parenting effort. As the Challenge Hypothesis is extended across the life course, DHEA and androstenedione (rather than testosterone) appear more responsive to juvenile male competitive behavior, and during reproductive senescence, baseline male testosterone levels decrease just as male life history allocations show decreased mating effort. We discuss how research on testosterone administration, particularly in older men, provides causal insight into effects of testosterone in humans, and how this "natural experiment" can be viewed in light of the Challenge Hypothesis. We synthesize central concepts and findings, such as an expanded array of costs of testosterone that inform life history tradeoffs between maintenance and reproductive effort, and we conclude with directions for future research.
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7.
Vitamin D Effects on the Immune System from Periconception through Pregnancy.
Schröder-Heurich, B, Springer, CJP, von Versen-Höynck, F
Nutrients. 2020;(5)
Abstract
Vitamin D is a well-known secosteroid and guardian of bone health and calcium homeostasis. Studies on its role in immunomodulatory functions have expanded its field in recent years. In addition to its impact on human physiology, vitamin D influences the differentiation and proliferation of immune system modulators, interleukin expression and antimicrobial responses. Furthermore, it has been shown that vitamin D is synthesized in female reproductive tissues and, by modulating the immune system, affects the periconception period and reproductive outcomes. B cells, T cells, macrophages and dendritic cells can all synthesize active vitamin D and are involved in processes which occur from fertilization, implantation and maintenance of pregnancy. Components of vitamin D synthesis are expressed in the ovary, decidua, endometrium and placenta. An inadequate vitamin D level has been associated with recurrent implantation failure and pregnancy loss and is associated with pregnancy-related disorders like preeclampsia. This paper reviews the most important data on immunomodulatory vitamin D effects in relation to the immune system from periconception to pregnancy and provides an insight into the possible consequences of vitamin D deficiency before and during pregnancy.
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8.
Nickel toxicology with reference to male molecular reproductive physiology.
Rizvi, A, Parveen, S, Khan, S, Naseem, I
Reproductive biology. 2020;(1):3-8
Abstract
The toxicity of metals is a known phenomenon. Nickel toxicity is very common since nickel is used extensively both industrially and in items of personal use such as utensils and jewellery. Here we discuss human exposure to nickel and its toxicity in the light of the available scientific evidence to understand its underlying pathophysiology. The ability of Ni+2 to get oxidized to Ni+3 renders it's potential of generating reactive oxygen species (ROS) in the system leading to oxidative stress. Carcinogenesis, apoptosis induction, contact dermatitis, epigenetic changes, and alteration in gene regulation are a result of overexposure of nickel. Our focus is on how nickel affects the male reproductive physiology. Nickel primarily drives ROS mediated perturbations in the male reproductive system. It influences zinc metabolism, which is critical for sperm stability and affects the structure of DNA binding proteins, including protamines, thereby affecting sperm function.
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9.
The impact of probiotic supplementation on metabolic health in healthy women of reproductive age: a systematic review.
Byrne, DF, Geraghty, AA, Yelverton, CA, Murphy, EF, Van Sinderen, D, Cotter, PD, McAuliffe, FM
Food & function. 2020;(12):10279-10289
Abstract
Products containing probiotics are targeted at healthy or at-risk individuals as a preventative measure to minimise disease risk. Most studies assessing the efficacy of probiotics in humans include a mixture of healthy and unhealthy populations, while studies that focus solely on female populations are largely limited to pregnancy or those with health conditions. Pre-conception is a significant time-point during the life-course, and improving female health status during this period may positively influence future offspring. The objective of this review is to assess the effect of probiotics administered in oral capsule formulation, on metabolic and immune markers in healthy, non-pregnant women of reproductive age. This review followed the PRISMA guidelines. Pubmed, EMBASE, CINAHL, and Web of Science were searched for relevant studies. English language articles relating to randomised-controlled trials were included. The search returned 3250 publications after duplicates were removed. Title (2516), abstract (642), and full text (87) screening excluded 3993 studies from consideration. Five papers were identified with outcomes of interest, and analysis of these showed no conclusive evidence that probiotic capsule supplementation elicited positive effects in this healthy population. This study highlights the need for further research to investigate the role that probiotics play during the pre-conception period, on female metabolic and immune health.
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10.
The genus Closterium, a new model organism to study sexual reproduction in streptophytes.
Tsuchikane, Y, Sekimoto, H
The New phytologist. 2019;(1):99-104
Abstract
Contents Summary 99 I. Introduction 99 II. Life cycle of Closterium 100 III. Sexual reproductive processes in the heterothallic Closterium peracerosum-strigosum-littorale complex 101 IV. Homothallism in the C. psl. complex 102 V. Sexual reproduction and inheritance of mating types in Closterium ehrenbergii 102 VI. mt-determining gene of the C. psl. complex 103 VII. Future perspectives 103 Acknowledgements 103 References 103 SUMMARY Closterium occupies a key phylogenetic position as an ancestor of land plants and is the best-characterized Charophycean alga in terms of the process of sexual reproduction. Zygospores form as a result of sexual reproduction between genetically determined mating type plus (mt+ ) and mating type minus (mt- ) cells in heterothallic strains, or between clonal cells in homothallic strains. Here we review knowledge on the intercellular communication and mating type determination for successful sexual reproduction in Closterium. Using genomic information and transgenic techniques, the genus could be a model organism to study the mechanisms and evolution of sexual reproduction in streptophytes.