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Showing papers on "Prolactin published in 2019"


Journal ArticleDOI
TL;DR: This Review focuses on the newly discovered roles of prolactin in human health and disease, particularly its involvement in metabolic homeostasis including body weight control, adipose tissue, skin and hair follicles, pancreas, bone, the adrenal response to stress, the control of lactotroph cellHomeostasis and maternal behaviour.
Abstract: The principal role of prolactin in mammals is the regulation of lactation. Prolactin is a hormone that is mainly synthesized and secreted by lactotroph cells in the anterior pituitary gland. Prolactin signalling occurs via a unique transmembrane prolactin receptor (PRL-R). The structure of the PRL-R has now been elucidated and is similar to that of many biologically fundamental receptors of the class 1 haematopoietic cytokine receptor family such as the growth hormone receptor. The PRL-R is expressed in a wide array of tissues, and a growing number of biological processes continue to be attributed to prolactin. In this Review, we focus on the newly discovered roles of prolactin in human health and disease, particularly its involvement in metabolic homeostasis including body weight control, adipose tissue, skin and hair follicles, pancreas, bone, the adrenal response to stress, the control of lactotroph cell homeostasis and maternal behaviour. New data concerning the pathological states of hypoprolactinaemia and hyperprolactinaemia will also be presented and discussed. Prolactin is mainly known for its involvement in the regulation of lactation. In this Review, the authors describe other newly discovered roles of prolactin in human health and disease and discuss new data on the pathological states of hypoprolactinaemia and hyperprolactinaemia.

126 citations


Journal ArticleDOI
05 Apr 2019
TL;DR: In this paper, the pituitary gland, ovaries and testes are already able to respond to specific stimuli long before puberty, and they may also be involved indirectly due to changes in the feedback system modulating gonadotrophin secretion.
Abstract: In four studies secretion patterns of LH, FSH, prolactin, testosterone and progesterone were measured in male and female cattle to determine endocrine changes associated with sexual maturation. Two periods of increasing gonadotrophin secretion were observed, the second one coinciding with puberty. A short luteal phase of 8-12 days precedes the first oestrus at 10-11 or 14 months of age. The testosterone values of the bulls increased with age from 5-6 months. Prolactin levels in the bulls increased at the time of the first testosterone rise. A frequency of about 1-2 LH and FSH pulses/8 h occurred at 1, 2, 5 and 10 months of age. The pituitary response to GnRH (1 microgram/kg i.v.) was tested in 2 male and 2 female calves at monthly intervals. LH and FSH were released at all ages but a reduced FSH response occurred in both sexes after the 5th month. A small testosterone release was observed as early as 1 month after birth in males similar to those observed after endogenous LH pulses. We conclude that the initiation of puberty in both sexes is controlled by the same neuroendocrine mechanisms. The pituitary gland, ovaries and testes are already able to respond to specific stimuli long before puberty, and they may also be involved indirectly due to changes in the feedback system modulating gonadotrophin secretion.

104 citations


Journal ArticleDOI
05 Apr 2019
TL;DR: Ruminant placentae produce at least two distinct subclasses of the growth hormone/prolactin gene family, the placental lactogens and prolactin-related proteins.
Abstract: Ruminant placentae produce at least two distinct subclasses of the growth hormone/prolactin gene family, the placental lactogens and prolactin-related proteins. Placental lactogens have been purified from cattle, goat and sheep placentae, and the amino acid sequences of bovine and ovine placental lactogen are known. Bovine and ovine placental lactogens are structurally more similar to prolactin than they are to growth hormone. In addition, six unique mRNAs have been described in cattle that encode prolactin-related proteins that are structurally distinct from ruminant placental lactogens. All characterized ruminant placental lactogens and prolactin-related proteins are products of chorionic binucleate cells, but specific biological functions of these placental hormones have not been elucidated. Ovine placental lactogen may modify maternal and fetal intermediary metabolism to provide energy substrates to the fetus. Bovine placental lactogen has been implicated as a luteotropic agent, and is also capable of stimulating mammogenesis and lactogenesis. No ruminant placental lactogen receptor has been structurally characterized, although they are presumed to be similar to either the growth hormone or prolactin receptor. Available technologies will allow many of the questions regarding the regulation, mechanism of action and function of these placental hormones to be addressed.

70 citations


Journal ArticleDOI
05 Apr 2019
TL;DR: In this article, the hourly fluctuations in the circulating levels of prolactin, luteinizing hormone (LH) and melatonin were measured in rams kept under various artificial lighting conditions.
Abstract: In the ram, changes in daylength influence testicular activity by modifying the release of luteinizing hormone-releasing hormone (LH-RH) and thus the gonadotrophins. To investigate the nature of this response the hourly fluctuations in the circulating levels of prolactin, luteinizing hormone (LH) and melatonin were measured in rams kept under various artificial lighting conditions. In Exp. 1, 8 Soay rams (4 control and 4 from which the superior cervical ganglia had been removed) were exposed to alternating 16-week periods of short days (8L: 16D) and long days (16L: 8D) for over 2 years, and blood samples were collected hourly for 25 h on two occasions. The lighting regimen resulted in marked testicular and endocrine changes in the controls but not in the ganglionectomized rams which had low or undetectable levels of melatonin (less than or equal to 33 pg/ml) and an unusual diurnal rhythm in prolactin. In Exp. 2, 8 intact Soay rams were exposed to an ahemeral lighting regimen of 8L: 28D for 16 weeks; at the end of this period blood samples were collected hourly for 52 h and assayed for prolactin. During the pretreatment period of long days (16L: 8D), the testes became fully regressed. During the 16 weeks of 8L: 28D, redevelopment occurred, but the growth of the testes was slow compared to that normally occurring under short days of 8L: 16D. The prolactin profiles showed evidence of circadian rhythm in hormone secretion, with a correlation between the timing and duration of the rhythm and the degree of testicular development. These combined results support the idea that the photoperiodic response in the ram involves an interplay between the secretory activity of the pineal gland, and a light/dark entrained circadian mechanism in the brain.

44 citations


Journal ArticleDOI
TL;DR: Regulated TRH production in the hypothalamus, patterns of expression of TRH and its receptor in the body, its role in energy metabolism and in prolactin secretion are addressed in this review.

43 citations


Journal ArticleDOI
TL;DR: The authors attempt to provide a critical overview on the role of prolactin in the immune system, exploring its contribution to the development of autoimmune diseases.

43 citations


Journal ArticleDOI
TL;DR: It is demonstrated that the mTOR pathway is activated in PRLomas and that everolimus exhibits antiproliferative actions in vitro and is suggested to be a novel therapeutic option for some aggressive PRL-secreting tumors unresponsive to conventional treatments.
Abstract: CONTEXT Aggressive prolactin (PRL)-secreting pituitary adenomas that are resistant to conventional therapy with dopamine agonists, surgery, and radiation pose a therapeutic challenge. The mammalian target of rapamycin (mTOR) inhibitor everolimus is approved to treat neuroendocrine tumors (NETs), and cotreatment with the somatostatin receptor ligand octreotide improved median progression-free survival in patients with metastatic pancreatic NETs. PATIENT, INTERVENTION, AND RESULTS We describe off-label everolimus treatment of a prolactinoma (PRLoma) refractory to cabergoline, repeat surgical resection, and radiation therapy. Addition of everolimus to cabergoline led to decreased PRL levels and tumor regression after 5 months. Tumor size remained stable for 12 months, and although PRL levels rose, they remained below pretreatment levels. Immunohistochemical (IHC) evaluation of expression of key mTOR pathway drivers of cell proliferation revealed elevated phosphorylated (p-)AKT, p-4EBP1, and p-S6 in the index patient's tumor. IHC analysis of seven additional PRLomas demonstrated increased expression of nuclear p-AKT, cytoplasmic p-S6, and globally increased p-4EBP1 in the PRLomas compared with 11 autopsy-derived normal pituitary tissues. In in vitro studies in murine mammosomatotroph tumor GH3 cells, we observed that both the dopamine agonist cabergoline and the mTOR inhibitor everolimus inhibited GH3 cell proliferation and PRL secretion as single agents, and the synergistic effect was noted with combination treatment only on inhibition of PRL secretion but not proliferation. CONCLUSIONS In summary, our findings demonstrate that the mTOR pathway is activated in PRLomas and that everolimus exhibits antiproliferative actions in vitro. We suggest that everolimus may be a novel therapeutic option for some aggressive PRL-secreting tumors unresponsive to conventional treatments.

37 citations


Journal ArticleDOI
TL;DR: The data establish that during hyperprolactinemia, suppression of pulsatile LH secretion is mediated by Prlr on arcuate kisspeptin neurons, and conditional knockout of Prlr specifically in arcuate nucleus kisspept neurons prevented prolactin-induced suppression of LH secretion.
Abstract: Hyperprolactinemia causes infertility, but the specific mechanism is unknown. It is clear that elevated prolactin levels suppress pulsatile release of GnRH from the hypothalamus, with a consequent reduction in pulsatile LH secretion from the pituitary. Only a few GnRH neurons express prolactin receptors (Prlrs), however, and thus prolactin must act indirectly in the underlying neural circuitry. Here, we have tested the hypothesis that prolactin-induced inhibition of LH secretion is mediated by kisspeptin neurons, which provide major excitatory inputs to GnRH neurons. To evaluate pulsatile LH secretion, we collected serial blood samples from diestrous mice and measured LH levels by ultrasensitive ELISA. Acute prolactin administration decreased LH pulses in wild-type mice. Kisspeptin neurons in the arcuate nucleus and in the rostral periventricular area of the third ventricle (RP3V) acutely responded to prolactin, but prolactin-induced signaling in kisspeptin neurons was up to fourfold higher in the arcuate nucleus when compared with the RP3V. Consistent with this, conditional knockout of Prlr specifically in arcuate nucleus kisspeptin neurons prevented prolactin-induced suppression of LH secretion. Our data establish that during hyperprolactinemia, suppression of pulsatile LH secretion is mediated by Prlr on arcuate kisspeptin neurons.

36 citations


Journal ArticleDOI
TL;DR: It is crucial to explore the cross talk of pregnancy hormones during gestation, as this may have a greater impact on the overall changes to the cardiovascular system.
Abstract: Hormones have a vital duty in the conservation of physiological cardiovascular function during pregnancy. Alterations in oestrogen, progesterone and prolactin levels are associated with changes in the cardiovascular system to support the growing foetus and counteract pregnancy stresses. Pregnancy hormones are, however, also linked to numerous pathophysiological outcomes on the cardiovascular system. The expression and effects of the three main pregnancy hormones (oestrogen, prolactin and progesterone) vary depending on the gestation period. However, the reaction of a target cell also depends on the abundance of hormone receptors and impacts put forth by other hormones. Hormonal interaction may be synergistic, antagonistic or permissive. It is crucial to explore the cross talk of pregnancy hormones during gestation, as this may have a greater impact on the overall changes to the cardiovascular system.

36 citations


Journal ArticleDOI
TL;DR: It is shown that neoplastic pancreatic epithelium, as well as a subset of tissue-resident macrophages, express the prolactin receptor (PRLR), and targeting prolactIn together with IL-6, a known major activator of STAT3, could represent a novel therapeutic strategy for treating pancreatic cancer.
Abstract: Pancreatic ductal adenocarcinoma (PDAC) is associated with significant fibrosis. Recent findings have highlighted the pro-fibrotic activity of tissue-resident macrophages in the pancreatic cancer microenvironment. Here, we showed that neoplastic pancreatic epithelium, as well as a subset of tissue-resident macrophages, express the prolactin receptor (PRLR). HMGB1-induced prolactin expression in the pancreas maintained FAK1 and STAT3 phosphorylation within the epithelium and stroma. Gain-of-function and loss-of-function experiments demonstrated the essential role of prolactin in promoting collagen deposition, and fibrosis. Finally, the signaling cascade downstream of Prolactin/PRLR activated STAT3 rather than STAT5 in PDAC. These findings suggest that targeting prolactin together with IL-6, a known major activator of STAT3, could represent a novel therapeutic strategy for treating pancreatic cancer.

31 citations


Journal ArticleDOI
TL;DR: Findings show that short-term ozone inhalation promotes a shift in brainstem and hypothalamic gene expression that is dependent on the presence of circulating adrenal-derived stress hormones, and is likely to have profound downstream influence on systemic effects of ozone.

Journal ArticleDOI
TL;DR: A role for MIR205HG as an lncRNA that regulates growth hormone and prolactin production in the anterior pituitary is supported.

Journal ArticleDOI
TL;DR: A tumor-stromal paracrine pathway in which secretion by tumor cells of the COX-2 product prostaglandin E2 induces prolactin production by stromal cells, which activates signaling in disseminated tumor cells with upregulated Prolactin receptor expression is uncovered.
Abstract: Tumor-stromal communication within the microenvironment contributes to initiation of metastasis and may present a therapeutic opportunity. Using serial single-cell RNA sequencing in an orthotopic mouse prostate cancer model, we find up-regulation of prolactin receptor as cancer cells that have disseminated to the lungs expand into micrometastases. Secretion of the ligand prolactin by adjacent lung stromal cells is induced by tumor cell production of the COX-2 synthetic product prostaglandin E2 (PGE2). PGE2 treatment of fibroblasts activates the orphan nuclear receptor NR4A (Nur77), with prolactin as a major transcriptional target for the NR4A-retinoid X receptor (RXR) heterodimer. Ectopic expression of prolactin receptor in mouse cancer cells enhances micrometastasis, while treatment with the COX-2 inhibitor celecoxib abrogates prolactin secretion by fibroblasts and reduces tumor initiation. Across multiple human cancers, COX-2, prolactin, and prolactin receptor show consistent differential expression in tumor and stromal compartments. Such paracrine cross-talk may thus contribute to the documented efficacy of COX-2 inhibitors in cancer suppression.

Journal ArticleDOI
TL;DR: Prolactin effectively facilitates its own secretion, which is essential for lactation and maternal behavior, and provides evidence of a physiologically important, reversible alteration in the behavior of a specific population of hypothalamic neurons in the adult brain.

Journal ArticleDOI
TL;DR: The main aim of this paper is to review the different pathways of dopamine and its agonists in prolactinomas to help to gain a better understanding of their functions and drug resistance mechanisms.
Abstract: Dopamine agonists such as bromocriptine and cabergoline are the predominant treatment drugs for prolactinoma by inhibiting prolactin secretion and shrinking tumor size. However, the pathways of either dopamine or its agonists that lead to the death of cells are incompletely understood and some are even conflicting conclusions. The main aim of this paper is to review the different pathways of dopamine and its agonists in prolactinomas to help to gain a better understanding of their functions and drug resistance mechanisms.

Journal ArticleDOI
TL;DR: Results show that developmental exposure to GBH induces epigenetic changes in ESR1, which could be responsible for the altered male mammary gland development observed in GBH350-exposed animals.

Journal ArticleDOI
TL;DR: An overview of the evolution of dopamine agonists and their use in patients with PRL-secreting pituitary tumors, starting from the 1970s up to today, highlighting that normalization of PRL levels, restoration of eugonadism, and reduction of tumor mass can be achieved in the majority of patients by treatment with dopamine agonist.
Abstract: The discovery of dopamine inhibitory effects on prolactin secretion has led to an era of successful dopaminergic therapy for prolactinomas. Herein we provide an overview of the evolution of dopamine agonists and their use in patients with PRL-secreting pituitary tumors, starting from the 1970s up to today, highlighting that normalization of PRL levels, restoration of eugonadism, and reduction of tumor mass can be achieved in the majority of patients by treatment with dopamine agonists.

Journal ArticleDOI
TL;DR: This is the first time that a potential antioxidant effect of PRL has been described in hippocampal neurons exposed to glutamate excitotoxicity, opening questions of its potentiality for therapeutics.

Journal ArticleDOI
01 Jul 2019-Europace
TL;DR: Postpartum hormones oxytocin and prolactin prolong QT/APD in LQT2 by reducing IKs and by increasing Cav1.2 and RyR2 expression/transcription are contributing to the increased postpartal arrhythmic risk in L QT2.
Abstract: AIMS Women with long QT syndrome 2 (LQT2) have a particularly high postpartal risk for lethal arrhythmias We aimed at investigating whether oxytocin and prolactin contribute to this risk by affecting repolarization METHODS AND RESULTS In female transgenic LQT2 rabbits (HERG-G628S, loss of IKr), hormone effects on QT/action potential duration (APD) were assessed (02-200 ng/L) Hormone effects (200 ng/L) on ion currents and cellular APD were determined in transfected cells and LQT2 cardiomyocytes Hormone effects on ion channels were assessed with qPCR and western blot Experimental data were incorporated into in silico models to determine the pro-arrhythmic potential Oxytocin prolonged QTc and steepened QT/RR-slope in vivo and prolonged ex vivo APD75 in LQT2 hearts Prolactin prolonged APD75 at high concentrations As underlying mechanisms, we identified an oxytocin- and prolactin-induced acute reduction of IKs-tail and IKs-steady (-255%, oxytocin; -133%, prolactin, P < 005) in CHO-cells and LQT2-cardiomyocytes IKr currents were not altered This oxytocin-/prolactin-induced IKs reduction caused APD90 prolongation (+119%/+13%, P < 005) in the context of reduced/absent IKr in LQT2 cardiomyocytes Hormones had no effect on IK1 and ICa,L in cardiomyocytes Protein and mRNA levels of CACNA1C/Cav12 and RyR2 were enhanced by oxytocin and prolactin Incorporating these hormone effects into computational models resulted in reduced repolarization reserve and increased propensity to pro-arrhythmic permanent depolarization, lack of capture and early afterdepolarizations formation CONCLUSIONS Postpartum hormones oxytocin and prolactin prolong QT/APD in LQT2 by reducing IKs and by increasing Cav12 and RyR2 expression/transcription, thereby contributing to the increased postpartal arrhythmic risk in LQT2

Journal ArticleDOI
TL;DR: The present data suggest interesting new targets for medications that might be used in the early stages of drug abstinence, including single‐spike firing of the dopamine system, which offers an important target for therapy.
Abstract: The dopamine system-essential for mood and movement-can be activated in two ways: by excitatory inputs that cause burst firing and stamp-in learning or by slow excitatory or inhibitory inputs-like leptin, insulin, ghrelin, or corticosterone-that decrease or increase single-spike (pacemaker) firing rate and that modulate motivation. In the present study we monitored blood samples taken prior to and during intravenous cocaine or saline self-administration in rats. During cocaine-taking, growth hormone and acetylated ghrelin increased 10-fold; glucagon-like peptide-1 (GLP-1) doubled; non-acetylated ghrelin, insulin-like growth factor-1 (IGF-1), and corticosterone increased by 50% and adiponectin increased by 17%. In the same blood samples, leptin, insulin, gastric inhibitory polypeptide (GIP), and prolactin decreased by 40-70%. On the first day of testing under extinction conditions-where the animals earned unexpected saline instead of cocaine-5-fold increases were seen for growth hormone and acetylated ghrelin and equal changes-in amplitude and latency-were seen in each of the other cases except for IGF-1 (which increased at a slower rate). Single-spike firing affects the tonic activation level of the dopamine system, involving very different controls than those that drive burst firing; thus, the present data suggest interesting new targets for medications that might be used in the early stages of drug abstinence.

Journal ArticleDOI
05 Apr 2019
TL;DR: It appears that there are a number of different mechanisms for the neuroendocrine transmission of information about the time of day and duration of the external photoperiod to the sheep fetus throughout late gestation.
Abstract: We have investigated whether the maternal melatonin rhythm provides the fetus with either a circadian or seasonal 'signal' during development. Our findings provide evidence that melatonin can generate and entrain the early evening peak in the daily rhythm of fetal breathing movements. In contrast, daily variations in maternal and fetal prolactin concentrations are present in pinealectomized ewes, are altered by changes in the time of onset of darkness, but are unaltered by changes in the phase of the daily melatonin rhythm. The mechanisms that generate and control the daily prolactin rhythm before and after birth are therefore unknown. It is clear from a number of studies that the duration of the nocturnal melatonin signal provides the adult and fetal sheep with photoperiodic information. We investigated whether there are differences in the fetal plasma concentrations of prolactin in ewes held in long and short photoperiods after surgical disconnection of the fetal hypothalamus and pituitary and demonstrated that there was a fetal prolactin response to the external photoperiod in sheep fetuses in which the hypothalamo-pituitary axis was either intact or surgically disconnected. We have suggested that one potential extrahypothalamic site of action of maternal melatonin is at the pars tuberalis of the fetal pituitary. It appears therefore that there are a number of different mechanisms for the neuroendocrine transmission of information about the time of day and duration of the external photoperiod to the sheep fetus throughout late gestation.

Journal ArticleDOI
TL;DR: There is initial evidence that pulmonary maternal ENM exposure perturbs the normal gestational endocrine vascular axis via a kisspeptin-dependent mechanism, and decreased placental, which may adversely affect health outcomes.

Journal ArticleDOI
TL;DR: An unusual plurihormonal tumor co-expressing Pit-1 and SF-1 along with hormones made by cells of both lineages is reported and the possibility of a stem cell tumor with multiple lineage differentiation is proposed.
Abstract: Thyrotropin (TSH)-secreting pituitary tumors are the rarest functioning pituitary tumors. Nonetheless, they are not infrequently plurihormonal, as they may express/secrete hormones made by other pituitary cells derived from the Pit-1 lineage such as growth hormone (GH), prolactin (PRL), and α-subunit (αSU). However, adrenocorticotropin (ACTH) or gonadotropin secretion by such a tumor is exceptional. Although double pituitary tumors are rare, they often combine ACTH and GH secretion. A 41-year-old presented almost 2 years after delivering her 10th child; she had thyrotoxicosis (goiter and palpitations) masquerading as autoimmune postpartum thyroiditis. She was still breastfeeding and amenorrheic. She proved to have TSH, GH, PRL, and ACTH hypersecretion. Imaging revealed an invasive pituitary macrotumor. She had stigmata neither of Cushing’s disease nor of acromegaly. Prior to surgery, hormonal control was achieved for close to 1 year by combined octreotide and cabergoline treatment with significant shrinking of the tumor. Following surgery, pathology revealed a collision tumor; the dominant lesion was positive for GH, βTSH, βFSH, and αSU and expressed both Pit-1 and SF-1.The smaller lesion was a corticotroph tumor. We report an unusual plurihormonal tumor co-expressing Pit-1 and SF-1 along with hormones made by cells of both lineages. Its simultaneous occurrence adjacent to a corticotroph tumor raises questions regarding the pathogenesis of these tumors. We propose the possibility of a stem cell tumor with multiple lineage differentiation. We hypothesize that pregnancy might have played a permissive role in tumorigenesis.

Journal ArticleDOI
TL;DR: The review describes functional and structural features of different isoforms of prolactin receptor, mechanisms of signaling pathway activation, and molecular messengers involved in the transmission and termination of signal from the prolACTin receptor isoforms.
Abstract: The review describes functional and structural features of different isoforms of prolactin receptor, mechanisms of signaling pathway activation, and molecular messengers involved in the transmission and termination of signal from the prolactin receptor isoforms. Changes in the ratio between prolactin receptor isoforms, key mediators of prolactin signal transduction and termination in various organs and tissues, are analyzed. Special attention is given to the role of molecular mediators and the ratio between the isoforms in normal physiological functions and pathologies. Approaches for therapeutic correction of prolactin signaling impairments are discussed.

Journal ArticleDOI
TL;DR: A previously unknown role for the cation channel Trpc5 in prolactin homeostasis of female mice is revealed and strategies to explore the genetic basis of reproductive disorders and other malfunctions associated with defective prolactIn regulation in humans are provided.
Abstract: Dopamine neurons of the hypothalamic arcuate nucleus (ARC) tonically inhibit the release of the protein hormone prolactin from lactotropic cells in the anterior pituitary gland and thus play a central role in prolactin homeostasis of the body. Prolactin, in turn, orchestrates numerous important biological functions such as maternal behavior, reproduction, and sexual arousal. Here, we identify the canonical transient receptor potential channel Trpc5 as an essential requirement for normal function of dopamine ARC neurons and prolactin homeostasis. By analyzing female mice carrying targeted mutations in the Trpc5 gene including a conditional Trpc5 deletion, we show that Trpc5 is required for maintaining highly stereotyped infraslow membrane potential oscillations of dopamine ARC neurons. Trpc5 is also required for eliciting prolactin-evoked tonic plateau potentials in these neurons that are part of a regulatory feedback circuit. Trpc5 mutant females show severe prolactin deficiency or hypoprolactinemia that is associated with irregular reproductive cyclicity, gonadotropin imbalance, and impaired reproductive capabilities. These results reveal a previously unknown role for the cation channel Trpc5 in prolactin homeostasis of female mice and provide strategies to explore the genetic basis of reproductive disorders and other malfunctions associated with defective prolactin regulation in humans.

Journal ArticleDOI
TL;DR: Comparisons between antipsychotic-naive first-episode psychosis (AN-FEP) patients and healthy controls suggest that prolactin might play a neuroprotective role, especially in women, and plasma Prolactin levels showed a negative correlation with the SAPS scores in AN-F EP female patients.
Abstract: Patients with schizophrenia frequently present hyperprolactinemia as a consequence of antipsychotic treatment. However, an increase in circulating prolactin levels has also been shown in patients without previous treatment. Our objective was to compare prolactin levels between antipsychotic-naive first-episode psychosis (AN-FEP) patients and healthy controls (HC). As part of an FEP program (Programa Asistencial Fases Iniciales de Psicosis [PAFIP]), 270 AN-FEP patients and 153 HC were eligible for this study. Serum prolactin levels were measured by an automated immunochemiluminescent assay. Subjects' sex and having an AN-FEP diagnosis both had an effect on prolactin levels, with higher levels in women than in men, and in AN-FEP patients than in HC. Moreover, plasma prolactin levels showed a negative correlation with the SAPS scores in AN-FEP female patients. AN-FEP patients have increased levels of prolactin, which might be stress-induced. This, together with the association of higher prolactin with a lower severity of the disease, suggests that prolactin might play a neuroprotective role, especially in women.

Journal ArticleDOI
TL;DR: It is concluded that high prolactin levels in patients with T2DM are linked with diabetic complications and regarded as a beneficial phenomena to overcome IR and diabetic complications.
Abstract: Prolactin is a polypeptide hormone secreted from the anterior part of the pituitary gland which was implicated as a diabetogenic factor in the pathogenesis of type 2 diabetes mellitus (T2DM). Therefore, the aim of the present study was to evaluate prolactin serum levels in patients with T2DM regarding the effect of diabetic pharmacotherapy. Eighty patients with T2DM compared with 25 male healthy controls were recruited and divided into four groups: Group I – 29 patients with T2DM treated with metformin, Group II – 30 patients with T2DM treated with glyburide, Group III – 21 patients with T2DM treated with glyburide plus metformin, and Group IV – 25 control male healthy patients. Prolactin serum levels were high in patients with T2DM compared with controls (P

Journal ArticleDOI
TL;DR: Results indicate that the PRLR, acting within the pancreas, mediates maternal pancreatic adaptations to pregnancy and therefore its dysfunction may increase a woman's chances of becoming glucose intolerant during pregnancy.
Abstract: Prolactin (PRL) signaling has been implicated in the regulation of glucose homeostatic adaptations to pregnancy. In this report, the PRL receptor (Prlr) gene was conditionally disrupted in the pancreas, creating an animal model which proved useful for investigating the biology and pathology of gestational diabetes including its impacts on fetal and placental development. In mice, pancreatic PRLR signaling was demonstrated to be required for pregnancy-associated changes in maternal β cell mass and function. Disruption of the Prlr gene in the pancreas resulted in fewer insulin producing cells, which failed to expand appropriately during pregnancy resulting in reduced blood insulin levels and maternal glucose intolerance. This inability to sustain normal blood glucose balance during pregnancy worsened with age and a successive pregnancy. The etiology of the insulin insufficiency was attributed to deficits in regulatory pathways controlling β cell development. Additionally, the disturbance in maternal blood glucose homeostasis, was associated with fetal overgrowth and dysregulation of inflammation and prolactin-associated transcripts in the placenta. Overall, these results indicate that the PRLR, acting within the pancreas, mediates maternal pancreatic adaptations to pregnancy and therefore its dysfunction may increase a woman's chances of becoming glucose intolerant during pregnancy.

Journal ArticleDOI
TL;DR: Investigating whether somatomammotropin hormones are able to modulate the activity of critical neuronal components of the HPG axis, including kisspeptin neurons and cells of the ventral premammillary nucleus (PMv) revealed evidence that GH and PRL may affect the HPg axis via specific hypothalamic neurons.

Journal ArticleDOI
TL;DR: This review introduces the reader to general aspects concerning Prolactin and its receptors and to what is currently known about the role prolactin plays in the brain and, in particular, in the hippocampus.
Abstract: Among the more than 300 biological actions described for prolactin, its role in the neurogenic capacity of the hippocampus, which increases synaptogenesis and neuronal plasticity, consolidates memory and acts as a neuronal protector against excitotoxicity-effects mediated through its receptors are more recently known. The detection of prolactin in the hippocampus and its receptors, specifically in the Ammon's horn and dentate gyrus, opened up a new field of study on the possible neuroprotective effect of hormones in a structure involved in learning and memory, as well as in emotional and behavioral processes. It is currently known, although controversial, that prolactin may be related to sex and age and that the hormone could be synthesized in the hippocampus itself. However, the regulatory mechanisms of changes in prolactin or in its hippocampal receptors still remain unknown. This review introduces the reader to general aspects concerning prolactin and its receptors and to what is currently known about the role prolactin plays in the brain and, in particular, in the hippocampus.