Androgen receptor is widely expressed in bovine placentomes and up-regulated during differentiation of bovine trophoblast giant cells

Spatial and temporal expression profile of sex steroid receptors and antioxidant enzymes in the maternal-fetal interface of domestic cats

Sex steroids and antioxidant enzymes modulate uterine and placental physiology. Failures in the expression, signaling, and/or secretion of these mediators are associated with female infertility and gestational problems. However, there is no data on the expression profile of receptors for sex steroids and antioxidant enzymes in the maternal-fetal interface of domestic cats. Uterus and placenta samples from non-pregnant diestrus cats and cats in mid- and late pregnancy were used to analyze the protein and gene expression of the receptors for estrogen alpha (ERα), progesterone (PR), and androgen (AR) and the antioxidant enzymes superoxide dismutase 1 (SOD1), catalase, and glutathione peroxidase 1 (GPX1) by immunohistochemistry and qPCR. Higher uterine expression of ERα, Pr, and Sod1 was observed in the pregnant cats, especially in mid-pregnancy, compared to non-pregnant diestrus cats, as well as reduced endometrial catalase immunostaining. In the placenta, the mRNA expression of Erα, Pr, Ar, and Gpx1 was higher in late pregnancy in relation to mid-pregnancy. Moreover, weak or no placental expression was observed for catalase in mid- and late pregnancy, while strong immunostaining was observed for AR in trophoblasts and decidual cells in mid-pregnancy. The findings of this study demonstrated that pregnancy in female cats increases the uterine expression of sex steroid receptors and antioxidant enzymes, and that the placental expression of these mediators varies according to gestational age.

Beyond Prostate Cancer: An Androgen Receptor Splice Variant Expression in Multiple Malignancies, Non-Cancer Pathologies, and Development

Multiple studies have demonstrated the importance of androgen receptor (AR) splice variants (SVs) in the progression of prostate cancer to the castration-resistant phenotype and their utility as a diagnostic. However, studies on AR expression in non-prostatic malignancies uncovered that AR-SVs are expressed in glioblastoma, breast, salivary, bladder, kidney, and liver cancers, where they have diverse roles in tumorigenesis. AR-SVs also have roles in non-cancer pathologies. In granulosa cells from women with polycystic ovarian syndrome, unique AR-SVs lead to an increase in androgen production. In patients with nonobstructive azoospermia, testicular Sertoli cells exhibit differential expression of AR-SVs, which is associated with impaired spermatogenesis. Moreover, AR-SVs have been identified in normal cells, including blood mononuclear cells, neuronal lipid rafts, and the placenta. The detection and characterization of AR-SVs in mammalian and non-mammalian species argue that AR-SV expression is evolutionarily conserved and that AR-SV-dependent signaling is a fundamental regulatory feature in multiple cellular contexts. These discoveries argue that alternative splicing of the AR transcript is a commonly used mechanism that leads to an expansion in the repertoire of signaling molecules needed in certain tissues. Various malignancies appropriate this mechanism of alternative AR splicing to acquire a proliferative and survival advantage.

Sexual dimorphism in placental development and its contribution to health and diseases

According to the Developmental Origin of Health and Disease (DOHaD), intrauterine exposure to adverse environments can affect fetus and birth outcomes and lead to long-term disease susceptibility. Evidence has shown that neonatal outcomes and the timing and severity of adult diseases are sexually dimorphic. As the link between mother and fetus, the placenta is an essential regulator of fetal development programming. It is found that the physiological development trajectory of the placenta has sexual dimorphism. Furthermore, under pathological conditions, the placental function undergoes sex-specific adaptation to ensure fetal survival. Therefore, the placenta may be an important mediator of sexual dimorphism in neonatal outcomes and adult disease susceptibility. Few systematic reviews have been conducted on sexual dimorphism in placental development and its underlying mechanisms. In this review, sex chromosomes and sex hormones, as the main reasons for sexual differentiation of the placenta, will be discussed. Besides, in the etiology of fetal-originated adult diseases, overexposure to glucocorticoids is closely related to adverse neonatal outcomes and long-term disease susceptibility. Studies have found that prenatal glucocorticoid overexposure leads to sexually dimorphic expression of placental glucocorticoid receptor isoforms, resulting in different sensitivity of the placenta to glucocorticoids, and may further affect fetal development. The present review examines what is currently known about sex differences in placental development and the underlying regulatory mechanisms of this sex bias. This review highlights the importance of placental contributions to the origins of sexual dimorphism in health and diseases. It may help develop personalized diagnosis and treatment strategies for fetal development in pathological pregnancies.

A Potential Role and Contribution of Androgens in Placental Development and Pregnancy

Successful pregnancy requires the establishment of a highly regulated maternal-fetal environment. This is achieved through the harmonious regulation of steroid hormones, which modulate both maternal and fetal physiology, and are critical for pregnancy maintenance. Defects in steroidogenesis and steroid signaling can lead to pregnancy disorders or even fetal loss. The placenta is a multifunctional, transitory organ which develops at the maternal-fetal interface, and supports fetal development through endocrine signaling, the transport of nutrients and gas exchange. The placenta has the ability to adapt to adverse environments, including hormonal variations, trying to support fetal development. However, if placental function is impaired, or its capacity to adapt is exceeded, fetal development will be compromised. The goal of this review is to explore the relevance of androgens and androgen signaling during pregnancy, specifically in placental development and function. Often considered a mere precursor to placental estrogen synthesis, the placenta in fact secretes androgens throughout pregnancy, and not only contains the androgen steroid nuclear receptor, but also non-genomic membrane receptors for androgens, suggesting a role of androgen signaling in placental function. Moreover, a number of pregnancy disorders, including pre-eclampsia, gestational diabetes, intrauterine growth restriction, and polycystic ovarian syndrome, are associated with abnormal androgen levels and androgen signaling. Understanding the role of androgens in the placenta will provide a greater understanding of the pathophysiology of pregnancy disorders associated with androgen elevation and its consequences.

Identification of placental androgen receptor isoforms in a sheep model of maternal allergic asthma

Maternal asthma is known to impact intrauterine growth outcomes, which may be mediated, in part, by altered androgen signalling. Our aim was to explore whether the sheep placenta expresses androgen receptor (AR) isoforms and determine if the differential expression of AR protein isoforms is altered by maternal asthma. Four known AR isoforms were detected (AR-FL, AR-v1, AR-v7, and AR-45), and their expression and subcellular distribution was altered in the presence of maternal allergic asthma. These findings underscore the importance for in vivo models of maternal asthma to delineate molecular patterns that may contribute to feto-placental growth and development.

Placenta specific gene targeting to study histone lysine demethylase and androgen signaling in ruminant placenta

Reproductive efficiency is critically dependent on embryo survival, establishment of a successful pregnancy and placental development. Recent advances in gene editing technology have enabled investigators to use gene knockdown and knockout approaches to better understand the role of hormone signaling in placental function and fetal growth and development. In this review, an overview of ruminant placentation will be provided, including recent data highlighting the role of histone lysine demethylase 1A and androgen signaling in ruminant placenta and pregnancy. Studies in ruminant placenta establish a role for histone lysine demethylase 1A in controlling genetic networks necessary for important cellular events such as cell proliferation and angiogenesis, as well as androgen receptor signaling during early placentation.

Androgen receptor and histone lysine demethylases in ovine placenta

Sex steroid hormones regulate developmental programming in many tissues, including programming gene expression during prenatal development. While estradiol is known to regulate placentation, little is known about the role of testosterone and androgen signaling in placental development despite the fact that testosterone rises in maternal circulation during pregnancy and in placenta-induced pregnancy disorders. We investigated the role of testosterone in placental gene expression, and focused on androgen receptor (AR). Prenatal androgenization decreased global DNA methylation in gestational day 90 placentomes, and increased placental expression of AR as well as genes involved in epigenetic regulation, angiogenesis, and growth. As AR complexes with histone lysine demethylases (KDMs) to regulate AR target genes in human cancers, we also investigated if the same mechanism is present in the ovine placenta. AR co-immunoprecipitated with KDM1A and KDM4D in sheep placentomes, and AR-KDM1A complexes were recruited to a half-site for androgen response element (ARE) in the promoter region of VEGFA. Androgenized ewes also had increased cotyledonary VEGFA. Finally, in human first trimester placental samples KDM1A and KDM4D immunolocalized to the syncytiotrophoblast, with nuclear KDM1A and KDM4D immunostaining also present in the villous stroma. In conclusion, placental androgen signaling, possibly through AR-KDM complex recruitment to AREs, regulates placental VEGFA expression. AR and KDMs are also present in first trimester human placenta. Androgens appear to be an important regulator of trophoblast differentiation and placental development, and aberrant androgen signaling may contribute to the development of placental disorders.

Developmental programing: impact of testosterone on placental differentiation

Gestational testosterone treatment causes maternal hyperinsulinemia, intrauterine growth retardation (IUGR), low birth weight, and adult reproductive and metabolic dysfunctions. Sheep models of IUGR demonstrate placental insufficiency as an underlying cause of IUGR. Placental compromise is probably the cause of fetal growth retardation in gestational testosterone-treated sheep. This study tested whether testosterone excess compromises placental differentiation by its androgenic action and/or via altered insulin sensitivity. A comparative approach of studying gestational testosterone (aromatizable androgen) against dihydrotestosterone (non-aromatizable androgen) or testosterone plus androgen antagonist, flutamide, was used to determine whether the effects of testosterone on placental differentiation were programed by its androgenic actions. Co-treatment of testosterone with the insulin sensitizer, rosiglitazone, was used to establish whether the effects of gestational testosterone on placentome differentiation involved compromised insulin sensitivity. Parallel cohorts of pregnant females were maintained for lambing and the birth weight of their offspring was recorded. Placental studies were conducted on days 65, 90, or 140 of gestation. Results indicated that i) gestational testosterone treatment advances placental differentiation, evident as early as day 65 of gestation, and culminates in low birth weight, ii) placental advancement is facilitated at least in part by androgenic actions of testosterone and is not a function of disrupted insulin homeostasis, and iii) placental advancement, while helping to increase placental efficiency, was insufficient to prevent IUGR and low-birth-weight female offspring. Findings from this study may be of relevance to women with polycystic ovary syndrome, whose reproductive and metabolic phenotype is captured by the gestational testosterone-treated offspring.

Flutamide influences placental aldo-keto reductase family 1 member C1 (AKR1C1) expression in pigs

Aldo-keto reductase family 1 member C1 (AKR1C1) catalyses the conversion of progesterone into inactive 20α-dihydroxyprogesterone. It is suggested that AKR1C1 expression in the placenta prevents from the cytotoxic effect of progesterone on foetuses during late pregnancy. The aim of the study was to determine whether the anti-androgen flutamide administered during late pregnancy (83-89 days of gestation) or before parturition (101-107 days of gestation) influences AKR1C1 expression in the porcine placenta. AKR1C1 mRNA and protein levels were measured using real-time PCR and western blotting, respectively. Immunolocalization of AKR1C1 within placentas was also performed. Flutamide significantly increased AKR1C1 mRNA (p = 0.008) and protein (p = 0.019) expression only during the pre-parturient period in pigs. AKR1C1 protein was immunolocalized in the epithelial and stromal cells of foetal and maternal part of placenta at both stages of gestation. Following flutamide treatment, the intensity of staining was higher (p = 0.045) on day 108 of gestation. In conclusion, porcine placental AKR1C1 expression seems to be regulated by an androgen signalling pathway and may be involved in foetal survival by preventing the detrimental effect of progesterone.