Prolactin Synthesis Research Articles

What Do We Know about Peripartum Cardiomyopathy? Yesterday, Today, Tomorrow

Peripartum cardiomyopathy is a disease that occurs during or after pregnancy and leads to a significant decline in cardiac function in previously healthy women. Peripartum cardiomyopathy has a varying prevalence among women depending on the part of the world where they live, but it is associated with a significant mortality and morbidity in this population. Therefore, timely diagnosis, treatment, and monitoring of this disease from its onset are of utmost importance. Although many risk factors are associated with the occurrence of peripartum cardiomyopathy, such as conditions of life, age of the woman, nutrient deficiencies, or multiple pregnancies, the exact cause of its onset remains unknown. Advances in research on the genetic associations with cardiomyopathies have provided a wealth of data indicating a possible association with peripartum cardiomyopathy, but due to numerous mutations and data inconsistencies, the exact connection remains unclear. Significant insights into the pathophysiological mechanisms underlying peripartum cardiomyopathy have been provided by the theory of an abnormal 16-kDa prolactin, which may be generated in an oxidative stress environment and lead to vascular and consequently myocardial damage. Recent studies supporting this disease mechanism also include research on the efficacy of bromocriptine (a prolactin synthesis inhibitor) in restoring cardiac function in affected patients. Despite significant progress in the research of this disease, there are still insufficient data on the safety of use of certain drugs treating heart failure during pregnancy and breastfeeding. Considering the metabolic changes that occur in different stages of pregnancy and the postpartum period, determining the correct dosing regimen of medications is of utmost importance not only for better treatment and survival of mothers but also for reducing the risk of toxic effects on the fetus.

Bromocriptine sensitivity in bromocriptine-induced drug-resistant prolactinomas is restored by inhibiting FGF19/FGFR4/PRL.

At present, various treatment strategies are available for pituitary adenomas, including medications, surgery and radiation. The guidelines indicate that pharmacological treatments, such as bromocriptine (BRC) and cabergoline (CAB), are important treatments for prolactinomas, but drug resistance is an urgent problem that needs to be addressed. Therefore, exploring the mechanism of drug resistance in prolactinomas is beneficial for clinical treatment. In our research, BRC-induced drug-resistant cells were established. Previous RNA sequencing data and an online database were used for preliminary screening of resistance-related genes. Cell survival was determined by Cell Counting Kit-8 (CCK-8) assay, colony formation assays and flow cytometry. Quantitative real-time polymerase chain reaction (qRT‒PCR), western blotting, immunohistochemistry, immunofluorescence and Co-immunoprecipitation (Co-IP) were used to assess the molecular changes and regulation. The therapeutic efficacy of BRC and FGFR4 inhibitor fisogatinib (FISO) combination was evaluated in drug-resistant cells and xenograft tumors in nude mice. Consistent with the preliminary results of RNA sequencing and database screening, fibroblast growth factor 19 (FGF19) expression was elevated in drug-resistant cells and tumor samples. With FGF19 silencing, drug-resistant cells exhibited increased sensitivity to BRC and decreased intracellular phosphorylated fibroblast growth factor receptor 4 (FGFR4) levels. After confirming that FGF19 binds to FGFR4 in prolactinoma cells, we found that FGF19/FGFR4 regulated prolactin (PRL) synthesis through the ERK1/2 and JNK signaling pathways. Regarding the effect of targeting FGF19/FGFR4 on BRC efficacy, FISO and BRC synergistically inhibited the growth of tumor cells, promoted apoptosis and reduced PRL levels. Overall, our study revealed FGF19/FGFR4 as a new mechanism involved in the drug resistance of prolactinomas, and combination therapy targeting the pathway could be helpful for the treatment of BRC-induced drug-resistant prolactinomas.

Revealing Sexual Dimorphism in Prolactin Regulation From Early Postnatal Development to Adulthood in Murine Models.

Serum prolactin (PRL) levels exhibit a gradual rise both in male and female rats from birth to adulthood, with females consistently displaying higher levels compared to age-matched males. This pattern has traditionally been attributed to the development and maturation of endocrine and neuroendocrine networks responsible for regulating PRL synthesis and secretion. However, the effect of dopamine (DA), which acts as an inhibitory factor on lactotroph function, also increases from birth to puberty, particularly in females. Nonetheless, the secretion of PRL remains higher in females compared to males. On the other hand, the observed sex differences in serum PRL levels during early postnatal development cannot be attributed to the influence of estradiol (E2). While serum E2 levels gradually increase after birth, only after 45 days of life do the disparities in E2 levels between females and males become evident. These observations collectively suggest that neither the maturation of hypothalamic DA regulation nor the rise in E2 levels can account for the progressive and sustained elevation in serum PRL levels and the observed sexual dimorphism during postnatal development. This review highlights the importance of recent discoveries in animal models that shed light on inhibitory mechanisms in the control of PRL secretion within the pituitary gland itself, that is intrapituitary mechanisms, with a specific emphasis on the role of transforming growth factor β1 and activins in PRL secretion.

Hypoprolactinemia. Does it matter? Redefining the hypopituitarism and return from a mumpsimus : "Absence of proof is not the proof of absence".

Prolactin (PRL) is secreted by the lactotroph cells in the anterior pituitary gland which is under inhibitory control of dopamine. The mature human PRL has more than 300 physiological actions including lactation, reproduction, homeostasis, neuroprotection, behavior, water and electrolyte balance, immunoregulation and embryonic and fetal development. PRL is involved in the growth and development of mammary gland, preparation of the breast for lactation in the postpartum period, synthesis of milk, and maintenance of milk secretion. Abnormalities in the synthesis and secretion of PRL may result in hyperprolactinemia or hypoprolactinemia. Although hyperprolactinemia has been extensively investigated in the literature, because of the subtle or unclearly defined symptoms, hypoprolactinemia is a less-known and neglected disorder. Failure of lactation is a well-known clinical manifestation of hypoprolactinemia. Recent studies reveal that hypoprolactinemia may have some effects beyond lactation such as increased risk for metabolic abnormalities including insulin resistance, abnormal lipid profile, obesity and sexual dysfunction. Very low level of PRL is suggested to be avoided in patients receiving dopamin agonist treatment to prevent unwanted effects of hypoprolactinemia. Another important point is that hypoprolactinemia is not included in the classification of hypopituitarism. Anterior pituitary failure is traditionally classified as isolated, partial and complete (panhypopituitarism) hypopituitarism regardless of prolactin level. Therefore, there are two kinds of panhypopituitarism: panhypopituitarism with normal or high PRL level and panhypopituitarism with low PRL level. In this review, we present two personal cases, discuss the diagnosis of hypoprolactinemia, hypoprolactinemia associated clinical picture and suggest to redefine the classification of hypopituitarism.

FRI293 Phoenixin As A Novel Autocrine/Paracrine Factor Mediating Prolactin Regulation By Functional Interaction Of LH And IGF-I/-II In Carp Pituitary Cells

Abstract Disclosure: C. Ye: None. X. Qin: None. M. He: None. A.O. Wong: None. Phoenixin (PNX), a novel peptide identified by bioinformatics, is known to have pleiotropic functions mediated by its receptor GPR173. At present, very little is known for PNX regulation and the intracellular signaling for PNX expression is still unclear. Recently, PNX and GPR173 were cloned in grass carp and found to be co-expressed in carp lactotrophs. In carp pituitary cells, PNX was also confirmed to be a novel autocrine/paracrine factor maintaining/stimulating prolactin (PRL) synthesis & secretion. To unveil the functional role of PNX in PRL regulation, a systematic screening of >40 neuroendocrine factors/local growth factors was conducted in the same cell model to look for regulators with modulatory functions for both PNX and PRL in carp pituitary. Based on our study, IGF-I & -II were shown to elevate PNX mRNA level with parallel rise in PRL gene expression in carp pituitary cells whereas the opposite was true for the functional agonist of LH, namely hCG. In parallel experiment, PRL mRNA expression induced by IGF-I was negated by removing endogenous PNX using immunoneutralization with PNX antiserum. Besides, hCG inhibition on PNX & PRL gene expression could be mimicked by parallel treatment of LH but not FSH, whereas removal of endogenous LH by LH antiserum immunoneutralization could lead to the opposite effects. Of note, hCG co-treatment not only attenuated the PNX and PRL responses induced by IGF-I but also triggered notable suppression of IGF-I receptor (IGF1R) gene expression at pituitary cell level. In our study, IGF1R & insulin receptor (InsR) expressed in carp pituitary cells were both activated by IGF-I treatment, but IGF-I induced PNX and PRL mRNA expression could be blocked only by the inactivators for IGF1R but not InsR. Using a pharmacological approach, the gene expression of PNX and PRL induced by IGF-I was confirmed to be mediated through the PI3K/Akt and MEK1/2/ERK1/2 but not P38MAPK pathways. Our findings, as a whole, suggest that (i) IGF signals can induce PRL gene expression in carp pituitary via IGF1R coupled to PI3K/Akt & MAPK cascades and this stimulatory effect is mediated via local production of PNX, and (ii) LH released in the pituitary can act locally to inhibit both basal & IGF-induced PRL expression and these inhibitory actions are mediated by blocking pituitary expression of PNX & IGF1R. Presentation: Friday, June 16, 2023

Activation of SGK1/ENaC Signaling Pathway Improves the Level of Decidualization in Unexplained Recurrent Spontaneous Abortion.

Recurrent spontaneous abortion (RSA) is one of the most common complications during pregnancy and seriously affects women's physical and mental health. About 50% of RSA cases are of unknown etiology. Our previous study found that the decidual tissue of patients with unexplained recurrent spontaneous abortion (URSA) had low expression levels of serum and glucocorticoid-induced protein kinase (SGK) 1. Endometrial decidualization is a key link in the early stage of pregnancy and is crucial to the development and maintenance of pregnancy. Decidualization is the proliferation and differentiation of endometrial stromal cells into deciduals, which involves a complex physiological process such as ovarian steroid hormones (estrogen, progesterone, prolactin, etc.), growth factors, and intercellular signaling. The binding of estrogen and its receptor stimulates the synthesis of endometrial deciduating markers prolactin (PRL) and insulin-like growth factor binding protein 1 (IGFBP-1), which mediates the occurrence of decidualization. Among them, SGK1/ENaC is a signaling pathway closely related to decidualization. The purpose of this study was to further investigate the expression of SGK1 and decidualization-related molecules in the decidual tissue of URSA patients and to explore the potential mechanism of SGK1's protective effect in URSA patients and in mouse models. Decidual tissue samples from 30 URSA patients and 30 women who actively terminated pregnancy were collected, and a URSA mouse model was established and treated with dydrogesterone. Expression levels of SGK1 and its signaling pathway-related proteins (p-Nedd4-2, 14-3-3 protein and ENaC-a), estrogen and progesterone receptors (ERβ, PR), and decidualization markers (PRLR, IGFBP-1) were assessed. Our study found that SGK1, p-Nedd4-2, 14-3-3 proteins, and ENaC-a expression levels were reduced in the decidual tissue, the SGK1/ENaC signaling pathway was inhibited, and the expression levels of the decidualization markers PRLR and IGFBP-1 were downregulated in the URSA group compared with the controls. Additionally, the concentrations of E2, P, and PRL in the serum of mice were decreased in the URSA group compared with the controls. However, SGK1/ENaC pathway-related proteins, estrogen and progesterone and their receptors, and decidualization-related molecules were upregulated by dydrogesterone. These data suggest that estrogen and progesterone can induce decidualization by activating the SGK1/ENaC signaling pathway; disruption of this pathway can lead to the development of URSA. Dydrogesterone can increase the expression level of SGK1 protein in decidual tissue.

The Relation between Increasing Anxiety and Prolactin-Releasing Peptide in Rats.

PrRP, also known as prolactoliberin, is a bovine hypothalamic extract neurohormone that stimulates prolactin synthesis in a rat pituitary adenoma cell line and lactating rat pituitary cells. PrRP has been shown to control the intake of food and energy expenditure, but it may also have a role in stress sensitivity, reproduction, cardia productivity, secretion of endocrine components, and lately, neuroprotective characteristics, among others. The current study was performed to identify if prolactin-releasing peptide (PrRP) had any effect in increasing anxiety clinical features in rats as an animal model. The study included 114 Wistar handling-acclimated male rats (160 gm, 2 months old); divided randomly into three major groups. The rats were divided randomly into three major groups (38-control animals (38C), and 38-PrRP animals (38P), both were examined using the EPM test to test for stress-related signs, such as fear of height (5 mins duration for each rat). The maze was cleaned with water to eliminate the previous rat odor after the experiment for each rat was completed. The tests were performed between 13:00 to 17:00 of the day. Then, a week later, 38 (19-PrRP animals (19P) and 19-control animals (19C)) were examined using the SP test conducted between 13:00 to 16:00 of the day. Fifteen minutes before EPM, the 38C received intranasal 0.9%-10µl NaCl (per nostril), and 38P received intranasal 10-10mol/l-10 µl PrRP (per nostril), and the anxiety-related signs, such as time spent in open arms (less time means more anxious), during the EPM test were recorded. The 19P and 19C received 10-10mol/l-10µl PrRP and 0.9%-10µl NaCl, respectively, (intranasal, per nostril, and 15 minutes before the SP test, where a stranger rat was placed in a specific cage in front of each of the 19P and 19C animals in a separate cage, in which both cages provided visual and olfactory but no confrontational contact). The results showed that PrRP significantly (P<0.05) decreased the time spent by the treated rats on the open arms. In addition, PrRP revealed significant (P<0.05) decreases in the time spent close to the stranger rat, which means increased anxiety levels. The current findings revealed that prolactin-releasing peptide increases anxiety and decreases sociality in the studied male rats.

TRH Regulates the Synthesis and Secretion of Prolactin in Rats with Adenohypophysis through the Differential Expression of miR-126a-5p.

Prolactin (PRL) is an important hormone that is secreted by the pituitary gland and plays an important role in the growth, development and reproduction of organisms. Thyrotropin-releasing hormone (TRH) is a common prolactin-releasing factor that regulates the synthesis and secretion of prolactin. In recent studies, microRNAs (miRNAs) have been found to play a key role in the regulation of pituitary hormones. However, there is a lack of systematic studies on the regulatory role that TRH plays on the pituitary transcriptome, and the role of miRNAs in the regulation of PRL synthesis and secretion by TRH lacks experimental evidence. In this study, we first investigated the changes in PRL synthesis and secretion in the rat pituitary gland after TRH administration. The results of transcriptomic analysis after TRH treatment showed that 102 genes, including those that encode Nppc, Fgf1, PRL, Cd63, Npw, and Il23a, were upregulated, and 488 genes, including those that encode Lats1, Cacna2d1, Top2a, and Tfap2a, were downregulated. These genes are all involved in the regulation of prolactin expression. The gene expression of miR-126a-5p, which regulates the level of PRL in the pituitary gland, was screened by analysis prediction software and by a dual luciferase reporter system. The data presented in this study demonstrate that TRH can regulate prolactin synthesis and secretion through miR-126a-5p, thereby improving our understanding of the molecular mechanism of TRH-mediated PRL secretion and providing a theoretical basis for the role of miRNAs in regulating the secretion of pituitary hormones.

Relationship Between Genistein Intake and Body Mass Index (BMI) with Serum Prolactin Levels in Breastfeeding Women in the Area of Benowo and Kenjeran Public Health Centers

Mother's milk is considered the optimal substance for newborns because it provides complete nutrition, improves infant health, and increases immunity and low incidence of gastrointestinal disease. The development of the alveolar-lobular glands in the breast for the initiation of breastfeeding is the role of the prolactin hormone. Genistein is a type of isoflavonoid whose content is abundant in soybeans, and their processed products (tempeh and tofu) play a role in the synthesis of serum prolactin. Body Mass Index (BMI) indicates maternal nutritional status, which can also affect serum prolactin. This study will discuss the relationship between genistein intake and BMI on serum prolactin levels of nursing mothers. This research uses analytical observational research on 110 breastfeeding mothers in the Benowo and Kenjeran Health Center Work Areas, Surabaya. The results of Spearman's correlation test showed that there was a significant relationship between genistein intake on maternal serum prolactin levels (p=0.001) and BMI on maternal serum prolactin levels (p=0.036) (Pearson's test). The estrogenic properties of genistein are very similar to endogenous estrogens, which are thought to increase the formation of maternal serum prolactin levels and its activity which stimulated ductal elongation in mammary gland development. The increase in BMI levels in the body is go with an increase in serum prolactin levels due to the lack of availability of dopamine two receptor (D2R) sites in the body of nursing mothers. Keywords: Genistein intake Body Mass Index, Serum Prolactin Levels Exclusive breastfeeding Nutrition of breastfeeding mothers

Decipher the inhibitory potential of phytocompounds from Leptadenia reticulata on dopamine D2 receptor to enhance prolactin secretion.

Dopamine is secreted by the hypothalamus, which inhibits the proliferation and effectiveness of lactotroph cells that release prolactin via dopamine D2 receptor (D2R). D2R activation inhibits lactotroph cell prolactin synthesis and regulates prolactin gene expression. Although, commercial medications are available for hypogalactia and agalactia, various plant sources significantly alleviate these problems. Leptadenia reticulata (Jivanti) is one of the important medicinal plants often consumed by nursing mothers to improve breast milk production. However, mechanism and chemical constituents involved in the inhibition of D2R by Jivanti is unclear. Therefore, in this study the phytocompounds reported from Jivanti were used for in-silico analysis to predict D2R inhibitory potential. The binding affinity value of campesterol and β-sitosterol (- 10.1 and -10.0 kcal/mol) with D2R has high revealed by molecular docking and stable interaction reveled by molecular dynamics simulation. Thus, these lead compounds could exert more D2R inhibitory activity resulting into prolactin release, which may lead to an increase in breast milk production. Although all selected compounds had fine permeation, non-toxic, and non-carcinogenic characteristics predicted by ADMET, campesterol had good solubility, absorption characteristics compared to other. Therefore, Jivanti, which is traditionally known medicinal plant, could be explored as a medication candidate to boost breast milk production.

Current research opportunities for potential phytotherapeutic agents for the treatment of pathologies of the female reproductive system

Introduction and aim. Herbal medicine is prescribed for various disorders of the menstrual cycle (uterine bleeding, dysmenorrhea), for the treatment of premenstrual and climacteric syndromes, inflammatory diseases of the genital organs, mastopathy and mastalgia and other pathological conditions. The aim of the study is to analysis and generalization of data from professional literature and own experience in the treatment of patients with pathologies of the female reproductive system by phytotherapeutic methods, taking into account the influence of medicinal plants on various links in the pathogenesis of the disease, as well as making recommendations for improvement and prospects for the use of phytotherapy in the treatment of this pathology. Material and methods. To make an analysis of literary sources of domestic and foreign authors about usage of medicinal plants for the treatment of pathologies of the female reproductive system. Analysis of the literature. In the treatment of primary (spasmodic) dysmenorrhea, herbal remedies with an antispasmodic, analgesic, hormone-mimetic effects are prescribed. It can be Chamomile (Matricaria chamomilla L.), Achillea millefolium, commonly known as yarrow, Viburnum, Shepherd’s purse (Capsella bursa-pastoris), Greater celandine, Atropa belladonna, Hyoscyamus niger, commonly known as henbane, black henbane, or stinking nightshade and Abraham’s tree. Many plants have bactericidal activity, and this property is used in the treatment of inflammatory diseases of the mucous membranes and skin. Such properties are possessed by flowers of Chamomile (Matricaria chamomilla L.), Calendula officinalis, infusion of Medicinal sage (Salvia officinalis L.). For the treatment of functional hyperprolactinemia phytopreparations are also successfully used. It is known that the medicinal plant Vitex agnus castus has dopaminergic properties, selectively blocking prolactin synthesis, and reduces follicle stimulating hormone levels. Strychnos ignatia, Caulophyllum thalictroides, European cyclamen, Lilium tigrinum, Iris versicolor provide a complex effect on the female body, effectively reduces the level of prolactin and the severity of mastalgia, which is confirmed not only by clinical data, but also by mammography data in fibrocystic breast disease. For the treatment of climacteric syndrome, a large number of medicinal plants are used, in particular, the most popular is the Cimicifuga racemose. Conclusion. The effectiveness of phytotherapeutic drugs has been verified by many clinical trials. Modern phytotherapy is becoming more widespread in clinical practice, as an alternative to drug treatment.

Herbal Lactagogum And Breastfeeding Mother's Breast Milk Production: A Sistematic Review

Background: Exclusive breastfeeding has a major contribution to the growth and development of toddlers, especially at 1,000 HPK. The coverage of exclusive breastfeeding in 2017 was still low at 35.7% compared to the WHO and the Ministry of Health's 2019 target which is 50%. One of the efforts to increase the coverage of exclusive breastfeeding is increase the quantity and quality of breast milk production, so as to increase the mother's motivation to give exclusive breastfeeding. Efforts to increase by using drugs / herbs are known as laktagogums. Lactagogum drugs are rarely known because they are relatively expensive. Therefore, the use of alternative lactogogum herbs derived from plants that can be consumed by breastfeeding mothers is very necessary. Objective: The purpose of this study was to analyze the herbal lactagogum on breast milk production. Methods: Literature review using the keywords laktagogum and herbs for breast milk production. Articles retrieved from Google Scholar, Science Direct, and Pub Med in the period 2009 to February 2019. In addition, relevant text books and guidelines were used to add further information or additional reports that were not identified in the electronic search. Results: Based on several experimental studies, it was shown that torbangun leaves, young papayas, moringa leaves, katuk leaves and banana buds contain chemical compounds that can stimulate the synthesis of prolactin and oxytocin to increase the production and secretion of breast milk. Conclusion: Lactagogum torbangun leaves, young papaya fruit, moringa leaves, katuk leaves and banana buds have a positive effect on increasing breast milk production. Keywords: herbs, lactagogum, breast milk production

Hematopoietic PBX-interacting protein is a novel regulator of mammary epithelial cell differentiation.

Hematopoietic PBX-interacting protein (HPIP, also known as PBXIP1) is an estrogen receptor (ER) interacting protein that regulates estrogen-mediated breast cancer cell proliferation and tumorigenesis. However, its functional significance in the context of mammary gland development is unexplored. Here, we report that HPIP is required for prolactin (PRL)-induced lactogenic differentiation invitro. Molecular analysis of HPIP expression in mice revealed its induced expression at pregnancy and lactation stages of mammary gland. Moreover, PRL is a lactogenic hormone that controls pregnancy as well as lactation and induces Hpip/Pbxip1 expression in a signal transducer and activator of transcription 5a-dependent manner. Using mammary epithelial and lactogenic-competent cell lines, we further show that HPIP plays a regulatory role in PRL-mediated mammary epithelial cell differentiation, which is measured by acini formation, β-casein synthesis, and lipid droplet formation. Further mechanistic studies using pharmacological inhibitors revealed that HPIP modulates PRL-induced β-casein synthesis via phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT) activation. This study also identified HPIP as a critical regulator of autocrine PRL signaling as treatment with the PRL receptor antagonist Δ1-9-G129R-hPRL restrained HPIP-mediated PRL synthesis, AKT activation, and β-casein synthesis in cultured HC11 cells. Interestingly, we also uncovered that microRNA-148a (miR-148a) antagonizes HPIP-mediated mammary epithelial cell differentiation. Together, our study identified HPIP as a critical regulator of PRL signaling and revealed a novel molecular circuitry involving PRL, HPIP, PI3K/AKT, and miR-148a that controls mammary epithelial cell differentiation invitro.

Influence of the expression vector and its elements on recombinant human prolactin synthesis in Escherichia coli; co-directional orientation of replication and transcription is highly critical

The aim of the present work was to define a bacterial expression system that is particularly efficient for the synthesis of recombinant human prolactin (hPRL). In previous work, based on experiments that were basically carried out in parallel with the present ones, the synthesis of rec-hPRL by the p1813-hPRL vector in E. coli HB2151 was >500 mg/L, while it was much lower here (2.5–4-fold), in the RB791 and RRI strains. The highest positive influence on rec-hPRL synthesis was due to the transcription-replication co-orientation of hPRL cDNA and the ori/antibiotic resistance gene, responsible for up to a ~ 5–6-fold higher expression yield. In conclusion, this work confirmed that each bacterial strain of E. coli has a genetic background that can allow a different level of heterologous protein synthesis. The individual study of each element indicated that its action critically depends on the reading orientation in which it is located inside the vector: co-directional orientation of replication and transcription, in fact, greatly increased the level of rec-hPRL expression.

Isolating the Role of Corticosterone in the Hypothalamic-Pituitary-Gonadal Transcriptomic Stress Response

Investigation of the negative impacts of stress on reproduction has largely centered around the effects of the adrenal steroid hormone, corticosterone (CORT), and its influence on a system of tissues vital for reproduction—the hypothalamus of the brain, the pituitary gland, and the gonads (the HPG axis). Research on the action of CORT on the HPG axis has predominated the stress and reproductive biology literature, potentially overshadowing other influential mediators. To gain a more complete understanding of how elevated CORT affects transcriptomic activity of the HPG axis, we experimentally examined its role in male and female rock doves (Columba livia). We exogenously administrated CORT to mimic circulating levels during the stress response, specifically 30 min of restraint stress, an experimental paradigm known to increase circulating CORT in vertebrates. We examined all changes in transcription within each level of the HPG axis as compared to both restraint-stressed birds and vehicle-injected controls. We also investigated the differential transcriptomic response to CORT and restraint-stress in each sex. We report causal and sex-specific effects of CORT on the HPG transcriptomic stress response. Restraint stress caused 1567 genes to uniquely differentially express while elevated circulating CORT was responsible for the differential expression of 304 genes. Only 108 genes in females and 8 in males differentially expressed in subjects that underwent restraint stress and those who were given exogenous CORT. In response to elevated CORT and restraint-stress, both sexes shared the differential expression of 5 genes, KCNJ5, CISH, PTGER3, CEBPD, and ZBTB16, all located in the pituitary. The known functions of these genes suggest potential influence of elevated CORT on immune function and prolactin synthesis. Gene expression unique to each sex indicated that elevated CORT affected more gene transcription in females than males (78 genes versus 3 genes, respectively). To our knowledge, this is the first study to isolate the role of CORT in HPG genomic transcription during a stress response. We present an extensive and openly accessible view of the role corticosterone in the HPG transcriptomic stress response. Because the HPG system is well conserved across vertebrates, these data have the potential to inspire new therapeutic strategies for reproductive dysregulation in multiple vertebrate systems, including our own.

MiR-375 acts as a novel factor modulating pituitary prolactin synthesis through Rasd1 and Esr1.

Prolactin (PRL) is a pituitary hormone that regulates multiple physiological processes. However, the mechanisms of PRL synthesis have not been fully elucidated. The aims of the present study were to study the functions and the related mechanisms of miR-375 regulating PRL synthesis. We initially found that miR-375 mainly expressed in the lactotrophs of mouse pituitary gland. To identify the function of miR-375 in the pituitary gland, the miR-375 knockout mice were generated by using Crispr/Cas9 technique. The results showed that miR-375 knockout resulted in the decline of pituitary PRL mRNA and protein levels by 75.7 and 60.4%, respectively, and the serum PRL level reduced about 46.1%, but had no significant effect on FSH, LH and TSH. Further, we identified that Estrogen receptor 1 (alpha) (Esr1) was a downstream molecule of miR-375. The real-time PCR and Western blot results showed that ESR1 mRNA and protein levels markedly decreased by 40.9 and 42.9% in the miR-375 knockout mouse pituitary, and these were subsequently confirmed by the in vitro study using transfections of miR-375 mimics and inhibitors in pituitary lactotroph GH4 cells. Further, Rasd1 was predicted by bioinformatic tools and proved to be the direct target of miR-375 in lactotrophs using the dual-luciferase reporter assay. Rasd1-siRNA transfection results revealed the negative effect of Rasd1 in regulating ESR1. Collectively, the results presented here demonstrate that miR-375 positively modulates PRL synthesis through Rasd1 and Esr1, which are crucial for understanding the regulating mechanisms of pituitary hormone synthesis.

The Choroid Plexus Is an Alternative Source of Prolactin to the Rat Brain.

Among the more than 300 functions attributed to prolactin (PRL), this hormone has been associated with the induction of neurogenesis and differentiation of olfactory neurons especially during pregnancy, which are essential for maternal behavior. Despite the original hypothesis that PRL enters the central nervous system through a process mediated by PRL receptors (PRLR) at the choroid plexus (CP), recent data suggested that PRL transport into the brain is independent of its receptors. Based on transcriptomic data suggesting that PRL could be expressed in the CP, this work aimed to confirm PRL synthesis and secretion by CP epithelial cells (CPEC). The secretion of PRL and the distribution of PRLR in CPEC were further characterized using an in vitro model of the rat blood-cerebrospinal fluid barrier. RT-PCR analysis of PRL transcripts showed its presence in pregnant rat CP, in CPEC, and in the rat immortalized CP cell line, Z310. These observations were reinforced by immunocytochemistry staining of PRL in CPEC and Z310 cell cytoplasm. A 63-kDa immunoreactive PRL protein was detected by Western blot in CP protein extracts as well as in culture medium incubated with rat pituitary and samples of rat cerebrospinal fluid and serum. Positive immunocytochemistry staining of PRLR was present throughout the CPEC cytoplasm and in the apical and basal membrane of these cells. Altogether, our evidences suggest that CP is an alternative source of PRL to the brain, which might impact neurogenesis of olfactory neurons at the subventricular zone, given its proximity to the CP.

Зміни складу козиного молока за теплового стресу в умовах господарства степової зони України

The aim of the study was to identify the relationship between milk indicators of dairy goats that are staying under heat stress with the climatic conditions of the Ukrainian steppe zone. The main research areas of animals’ reaction to temperature stress were monitoring their physiological state, changes in behavior and metabolism through the neuroendocrine mechanisms of their regulation, assessing the immune system functional state, the antioxidant defense system, and determining the activity of the microbiota of the gastrointestinal tract. It is important to control the respiratory rate of animals, which becomes especially important when the air humidity is high and the reversal of the fat/protein ratio in milk is detected. It occurs under stressful conditions and significantly affects the technological properties of milk, especially in animals with high milk productivity. It is useful to provide goats after kidding with the opportunity to stay for a long time with an adequate photoperiod, this will affect the synthesis of prolactin and the level of milk yield at the peak of lactation. When feeding highly productive animals, it becomes important to regulate both the appetite of animals and the composition of the diet. This is important to prevent digestive disorders because the state of the ruminant stomach microbiota of the feed affects the synthesis of the constituent components of milk. When breeding, attention should be paid to multiple pregnancies, because the long-term effect of gonadotropins and other biologically active substances from the placenta affects the ability of females to produce greater milk secretion in the next lactation. According to the obtained results, staying in the transition zone according to the THI (more than 65) affected some of the chemical parameters of goat’s milk. In particular, there was a decrease in fat content, and therefore also the dry matter content and the fat/protein ratio, as well as urea, as one of the indicators of the rumen microbiota state. A significant increase in the number of somatic cells was observed almost three times, which confirms the presence of stress response from the mammary gland. For an objective assessment of the animals’ welfare state in terms of climatic conditions, it is advisable to use the definitions of the temperature-humidity index, and to confirm the stress response in dairy goats from any factor of keeping and feeding – laboratory determination of stress biomarkers in the composition of blood, milk, and urine.

Morphological and immunohistochemical features of placenta in postpartum women with hyperprolactinemia history

Hyperprolactinemia (HP) is a persistent increase in serum prolactin levels, the most typical manifestation of which is a dysfunction of the reproductive system. Pregnant women with HP have a high incidence of perinatal complications; thus, the threat of self-abortion in these women is more than 48.4 %, and in 16.1 % of pregnant women it ends in premature birth. These patients often develop placental abnormalities that lead to fetal distress during pregnancy and childbirth.The aim: to investigate the morphological and immunohistochemical changes in the placental barrier, taking into account the expression of prolactin in postpartum women with a history of hyperprolactininemia.Materials and methods. In 30 puerperas with a history of endocrine infertility associated with hyperprolactinemia (group 1) and in 27 healthy puerperas without hyperprolactinemia and infertility (control group 2), the morphological features of the placentas were studied in the gestational period of 39–40 weeks using organometric, macroscopic, histological and immunohistochemical (IHC) methods.IHC studies were carried out on serial paraffin sections in accordance with standard protocols using monoclonal antibodies to prolactin (Rabbit a-Нu Prolactin Monoclonal Antibody (Clone EP 193) master diagnostica (Spain) and detection system Thermo scientific (USA).Results. The placenta weight of women in labor with hyperprolactinemia did not differ significantly from the weight of the placenta of women in labor without hyperprolactinemia. In 22 (73.3 %) postpartum women with hyperprolactinemia in the placenta, paracentral attachment of the umbilical cord took place, in 4 (13.3 %) patients malformation of the umbilical cord vessels was detected, in 7 (23.3 %) postpartum women significant stenosis and closure of the arterial lumen vessels of the umbilical cord were found. Histological examination of women in labor with hyperprolactinemia identified focal thickening of the decidua with the presence of significant fibrinoid masses (n = 18, 60 %), microbleeds and thinning of the decidua (n = 8, 26.6 % of women in labor). A number of observations revealed the presence of maternal internal infarctions with perivillous fibrin deposition, in 12 (40 %) postpartum women, the presence of fibrinoid-embedded villi with the replacement of the villus epithelium with fibrinoid masses was noted, in 15 (50 %) women fibrosis and collagenization of the stem and middle chorionic villi, fibrosis of small villi and avascular small villi was observed in 12 (40 %) postpartum women. In some observations, a decrease in the number of syncytial nodes and syncytiocapillary membranes was noted in the terminal villi. IHC study of the placenta of postpartum women with hyperprolactinemia in the gestational period of 39–40 weeks revealed multiple foci of decidual cells with overexpression of prolactin in the cytoplasm.Conclusions. Morphological changes in the placenta of postpartum women with hyperprolactinemia in anamnesis differ from changes in the placenta of women without hyperprolactinemia by the presence of focal vascular changes in the decidual membrane with its partial detachment and internal infarctions in the maternal part of the placenta, as well as by the presence of signs of partial perfusion disorders of the fetal foci placenta.In the placenta of women with hyperprolactinemia, immunohistochemical study revealed a long-term focal significant cytoplasmic expression of prolactin in the cells of the decidual membrane, which indicates disorders of prolactin synthesis in the body and discoordination in the work of the endocrine system of women.

Estrogen Receptors in Nonfunctioning Pituitary Neuroendocrine Tumors: Review on Expression and Gonadotroph Functions.

Estrogen (17β-estradiol or E2) is a crucial regulator of the synthesis and secretion of pituitary reproductive hormones luteinizing hormone, follicle-stimulating hormone, and prolactin. In this review, we summarize the role of estrogen receptors in nonfunctioning pituitary neuroendocrine tumors (NF-Pitnets), focusing on immunoexpression and gonadotroph cell proliferation and apoptosis. Gonadotroph tumors are the most common subtype of NF-Pitnets. Two major estrogen receptor (ER) isoforms expressed in the pituitary are estrogen receptor alpha (ERα) and estrogen receptor beta (ERβ). Overall, estrogen actions are mostly exerted through the ERα isoform on the pituitary. The G protein–coupled estrogen receptor (GPER) located at the plasma membrane may contribute to nongenomic effects of estrogen. Nuclear immunoreactivity for ERα and ERβ was highest among gonadotroph and null cell tumors. Silent corticotroph tumors are the least immunoreactive for both receptors. A significantly elevated ERα expression was observed in macroadenomas compared with microadenomas. ERα and ERβ may act in opposite directions to regulate the Slug-E-cadherin pathway and to affect invasiveness of NF-Pitnets. In the cellular pathway, ERs regulate estrogen-induced proliferation and differentiation and impact several signaling pathways including the MAPK and PI3K/Akt pathway. Estrogen was the first-discovered inducer of pituitary tumor transforming gene 1 that was abundantly expressed in NF-Pitnets. ERα can be a potential biomarker for predicting tumor size and invasiveness as well as therapeutic target for NF-Pitnets. Selective estrogen receptor modulators or antiestrogen may represent as an alternative choice for the treatment of NF-Pitnets.