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Nature Reviews. Endocrinology Jan 2023Lactation is critical to infant short-term and long-term health and protects mothers from breast cancer, ovarian cancer and type 2 diabetes mellitus. The mammary gland... (Review)
Review
Lactation is critical to infant short-term and long-term health and protects mothers from breast cancer, ovarian cancer and type 2 diabetes mellitus. The mammary gland is a dynamic organ, regulated by the coordinated actions of reproductive and metabolic hormones. These hormones promote gland development from puberty onwards and induce the formation of a branched, epithelial, milk-secreting organ by the end of pregnancy. Progesterone withdrawal following placental delivery initiates lactation, which is maintained by increased pituitary secretion of prolactin and oxytocin, and stimulated by infant suckling. After weaning, local cytokine production and decreased prolactin secretion trigger large-scale mammary cell loss, leading to gland involution. Here, we review advances in the molecular endocrinology of mammary gland development and milk synthesis. We discuss the hormonal functions of the mammary gland, including parathyroid hormone-related peptide secretion that stimulates maternal calcium mobilization for milk synthesis. We also consider the hormonal composition of human milk and its associated effects on infant health and development. Finally, we highlight endocrine and metabolic diseases that cause lactation insufficiency, for example, monogenic disorders of prolactin and prolactin receptor mutations, maternal obesity and diabetes mellitus, interventions during labour and delivery, and exposure to endocrine-disrupting chemicals such as polyfluoroalkyl substances in consumer products and other oestrogenic compounds.
Topics: Female; Humans; Pregnancy; Mammary Glands, Human; Oxytocin; Placenta; Prolactin; Lactation
PubMed: 36192506
DOI: 10.1038/s41574-022-00742-y -
Endocrine Reviews Apr 2020Synthetic progestogens (progestins) have been linked to increased breast cancer risk; however, the role of endogenous progesterone in breast physiology and... (Review)
Review
Synthetic progestogens (progestins) have been linked to increased breast cancer risk; however, the role of endogenous progesterone in breast physiology and carcinogenesis is less clearly defined. Mechanistic studies using cell culture, tissue culture, and preclinical models implicate progesterone in breast carcinogenesis. In contrast, limited epidemiologic data generally do not show an association of circulating progesterone levels with risk, and it is unclear whether this reflects methodologic limitations or a truly null relationship. Challenges related to defining the role of progesterone in breast physiology and neoplasia include: complex interactions with estrogens and other hormones (eg, androgens, prolactin, etc.), accounting for timing of blood collections for hormone measurements among cycling women, and limitations of assays to measure progesterone metabolites in blood and progesterone receptor isotypes (PRs) in tissues. Separating the individual effects of estrogens and progesterone is further complicated by the partial dependence of PR transcription on estrogen receptor (ER)α-mediated transcriptional events; indeed, interpreting the integrated interaction of the hormones may be more essential than isolating independent effects. Further, many of the actions of both estrogens and progesterone, particularly in "normal" breast tissues, are driven by paracrine mechanisms in which ligand binding to receptor-positive cells evokes secretion of factors that influence cell division of neighboring receptor-negative cells. Accordingly, blood and tissue levels may differ, and the latter are challenging to measure. Given conflicting data related to the potential role of progesterone in breast cancer etiology and interest in blocking progesterone action to prevent or treat breast cancer, we provide a review of the evidence that links progesterone to breast cancer risk and suggest future directions for filling current gaps in our knowledge.
Topics: Breast Neoplasms; Estrogens; Female; Humans; Progesterone; Receptors, Progesterone
PubMed: 31512725
DOI: 10.1210/endrev/bnz001 -
JCI Insight Mar 2020Semaglutide, a glucagon-like peptide 1 (GLP-1) analog, induces weight loss, lowers glucose levels, and reduces cardiovascular risk in patients with diabetes. Mechanistic...
Semaglutide, a glucagon-like peptide 1 (GLP-1) analog, induces weight loss, lowers glucose levels, and reduces cardiovascular risk in patients with diabetes. Mechanistic preclinical studies suggest weight loss is mediated through GLP-1 receptors (GLP-1Rs) in the brain. The findings presented here show that semaglutide modulated food preference, reduced food intake, and caused weight loss without decreasing energy expenditure. Semaglutide directly accessed the brainstem, septal nucleus, and hypothalamus but did not cross the blood-brain barrier; it interacted with the brain through the circumventricular organs and several select sites adjacent to the ventricles. Semaglutide induced central c-Fos activation in 10 brain areas, including hindbrain areas directly targeted by semaglutide, and secondary areas without direct GLP-1R interaction, such as the lateral parabrachial nucleus. Automated analysis of semaglutide access, c-Fos activity, GLP-1R distribution, and brain connectivity revealed that activation may involve meal termination controlled by neurons in the lateral parabrachial nucleus. Transcriptomic analysis of microdissected brain areas from semaglutide-treated rats showed upregulation of prolactin-releasing hormone and tyrosine hydroxylase in the area postrema. We suggest semaglutide lowers body weight by direct interaction with diverse GLP-1R populations and by directly and indirectly affecting the activity of neural pathways involved in food intake, reward, and energy expenditure.
Topics: Animals; Body Weight; Brain; Eating; Energy Metabolism; Glucagon-Like Peptide-1 Receptor; Glucagon-Like Peptides; Mice; Neural Pathways; Rats
PubMed: 32213703
DOI: 10.1172/jci.insight.133429 -
Frontiers in Endocrinology 2022Over the last years, the metabolic role of PRL has emerged. PRL excess is known to promote weight gain, obesity, metabolic syndrome, and impairment in gluco-insulinemic... (Review)
Review
Over the last years, the metabolic role of PRL has emerged. PRL excess is known to promote weight gain, obesity, metabolic syndrome, and impairment in gluco-insulinemic and lipid profiles, likely due to the suppression of physiologic dopaminergic tone. Prolactin receptors and dopamine receptors type 2 have been demonstrated to be expressed on both human pancreatic β- cell and adipocytes, supporting a key role of prolactin and dopamine in peripheral metabolic regulation. Medical treatment with the dopamine agonists bromocriptine and cabergoline has been demonstrated to decrease the prevalence of metabolic syndrome and obesity, and significantly improve gluco-insulinemic and lipid profiles. In hyperprolactinemic men with concomitant hypogonadism, correction of hyperprolactinaemia and testosterone replacement has been proven to restore metabolic impairment. In turn, low prolactin levels have also been demonstrated to exert a detrimental effect on weight gain, glucose and lipid metabolism, thus leading to an increased prevalence of metabolic syndrome. Therefore, PRL values ranging from 25 to 100 mg/L, in absence of other recognizable pathological causes, have been proposed to represent a physiological response to the request for an increase in metabolic activity, and nowadays classify the so-called HomeoFIT- PRL as a promoter of metabolic homeostasis. The current review focuses mainly on the effects of hyperprolactinemia and its control by medical treatment with DAs on the modulation of food intake, body weight, gluco-insulinemic and lipid profile. Furthermore, it provides the latest knowledge about the metabolic impact of hypoprolactinemia.
Topics: Bromocriptine; Cabergoline; Dopamine; Dopamine Agonists; Glucose; Humans; Hyperprolactinemia; Lipids; Male; Metabolic Syndrome; Obesity; Prolactin; Receptors, Dopamine; Receptors, Prolactin; Testosterone; Weight Gain
PubMed: 36237192
DOI: 10.3389/fendo.2022.1015520 -
International Journal of Molecular... Dec 2021Ever since the discoveries that human hair follicles (HFs) display the functional peripheral equivalent of the hypothalamic-pituitary-adrenal axis, exhibit elements of... (Review)
Review
Ever since the discoveries that human hair follicles (HFs) display the functional peripheral equivalent of the hypothalamic-pituitary-adrenal axis, exhibit elements of the hypothalamic-pituitary-thyroid axis, and even generate melatonin and prolactin, human hair research has proven to be a treasure chest for the exploration of neurohormone functions. However, growth hormone (GH), one of the dominant neurohormones of human neuroendocrine physiology, remains to be fully explored in this context. This is interesting since it has long been appreciated clinically that excessive GH serum levels induce distinct human skin pathology. Acromegaly, or GH excess, is associated with hypertrichosis, excessive androgen-independent growth of body hair, and hirsutism in females, while dysfunctional GH receptor-mediated signaling (Laron syndrome) is associated with alopecia and prominent HF defects. The outer root sheath keratinocytes have recently been shown to express functional GH receptors. Furthermore, and contrary to its name, recombinant human GH is known to inhibit female human scalp HFs' growth ex vivo, likely via stimulating the expression of the catagen-inducing growth factor, TGF-β2. These limited available data encourage one to systematically explore the largely uncharted role of GH in human HF biology to uncover nonclassical functions of this core neurohormone in human skin physiology.
Topics: Female; Hair Follicle; Human Growth Hormone; Humans; Receptors, Somatotropin; Skin
PubMed: 34948002
DOI: 10.3390/ijms222413205 -
The New England Journal of Medicine Apr 2020An oral compound, SEP-363856, that does not act on dopamine D2 receptors but has agonist activity at trace amine-associated receptor 1 (TAAR1) and 5-hydroxytryptamine... (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
An oral compound, SEP-363856, that does not act on dopamine D2 receptors but has agonist activity at trace amine-associated receptor 1 (TAAR1) and 5-hydroxytryptamine type 1A (5-HT) receptors, may represent a new class of psychotropic agent for the treatment of psychosis in schizophrenia.
METHODS
We performed a randomized, controlled trial to evaluate the efficacy and safety of SEP-363856 in adults with an acute exacerbation of schizophrenia. The patients were randomly assigned in a 1:1 ratio to receive once-daily treatment with SEP-363856 (50 mg or 75 mg) or placebo for 4 weeks. The primary end point was the change from baseline in the total score on the Positive and Negative Symptom Scale (PANSS; range, 30 to 210; higher scores indicate more severe psychotic symptoms) at week 4. There were eight secondary end points, including the changes from baseline in the scores on the Clinical Global Impressions Severity (CGI-S) scale and the Brief Negative Symptom Scale (BNSS).
RESULTS
A total of 120 patients were assigned to the SEP-363856 group and 125 to the placebo group. The mean total score on the PANSS at baseline was 101.4 in the SEP-363856 group and 99.7 in the placebo group, and the mean change at week 4 was -17.2 points and -9.7 points, respectively (least-squares mean difference, -7.5 points; 95% confidence interval, -11.9 to -3.0; P = 0.001). The reductions in the CGI-S and BNSS scores at week 4 were generally in the same direction as those for the primary outcome, but the results were not adjusted for multiple comparisons. Adverse events with SEP-363856 included somnolence and gastrointestinal symptoms; one sudden cardiac death occurred in the SEP-363856 group. The incidence of extrapyramidal symptoms and changes in the levels of lipids, glycated hemoglobin, and prolactin were similar in the trial groups.
CONCLUSIONS
In this 4-week trial involving patients with an acute exacerbation of schizophrenia, SEP-363856, a non-D2-receptor-binding antipsychotic drug, resulted in a greater reduction from baseline in the PANSS total score than placebo. Longer and larger trials are necessary to confirm the effects and side effects of SEP-363856, as well as its efficacy relative to existing drug treatments for patients with schizophrenia. (Funded by Sunovion Pharmaceuticals; ClinicalTrials.gov number, NCT02969382.).
Topics: Acute Disease; Administration, Oral; Adult; Antipsychotic Agents; Double-Blind Method; Drug Administration Schedule; Female; Humans; Least-Squares Analysis; Male; Receptors, Dopamine D2; Receptors, G-Protein-Coupled; Schizophrenia; Schizophrenic Psychology; Serotonin 5-HT1 Receptor Agonists; Severity of Illness Index; Treatment Outcome
PubMed: 32294346
DOI: 10.1056/NEJMoa1911772 -
Molecular and Cellular Endocrinology Feb 2020Prolactin is pleotropic in nature affecting multiple tissues throughout the body. As a consequence of the broad range of functions, regulation of anterior pituitary... (Review)
Review
Prolactin is pleotropic in nature affecting multiple tissues throughout the body. As a consequence of the broad range of functions, regulation of anterior pituitary prolactin secretion is complex and atypical as compared to other pituitary hormones. Many studies have provided insight into the complex hypothalamic-pituitary networks controlling prolactin secretion patterns in different species using a range of techniques. Here, we review prolactin secretion in both males and females; and consider the different patterns of prolactin secretion across the reproductive cycle in representative female mammals with short versus long luteal phases and in seasonal breeders. Additionally, we highlight changes in the pattern of secretion during pregnancy and lactation, and discuss the wide range of adaptive functions that prolactin may have in these important physiological states.
Topics: Animals; Female; Humans; Lactation; Luteal Phase; Male; Pregnancy; Prolactin
PubMed: 31843563
DOI: 10.1016/j.mce.2019.110679 -
Pharmacology & Therapeutics Jul 2023Women experience chronic pain more often than men with some pain conditions being specific to women while others are more prevalent in women. Prolactin, a neuropeptide... (Review)
Review
Women experience chronic pain more often than men with some pain conditions being specific to women while others are more prevalent in women. Prolactin, a neuropeptide hormone with higher serum levels in women, has recently been demonstrated in preclinical studies to sensitize nociceptive sensory neurons in a sexually dimorphic manner. Dysregulation of prolactin and prolactin receptors may be responsible for increased pain especially in female predominant conditions such as migraine, fibromyalgia, and pelvic pain. In this review, we focus on the role of prolactin in endometriosis, a condition characterized by pelvic pain and infertility that affects a large proportion of women during their reproductive age. We discuss the symptoms and pathology of endometriosis and discuss how different sources of prolactin secretion may contribute to this disease. We highlight our current understanding of prolactin-mediated mechanisms of nociceptor sensitization in females and how this mechanism may apply to endometriosis. Lastly, we report the results of a systematic review of clinical studies conducted by searching the PubMed and EMBASE databases to identify association between endometriosis and blood levels of prolactin. The results of this search strongly indicate that serum prolactin levels are increased in patients with endometriosis and support the possibility that high levels of prolactin may promote pelvic pain in these patients and increase vulnerability to other comorbid pain conditions likely by dysregulating prolactin receptor expression. Targeting of prolactin and prolactin receptors may improve management of pain associated with endometriosis.
Topics: Female; Humans; Endometriosis; Prolactin; Receptors, Prolactin; Pelvic Pain; Chronic Pain
PubMed: 37169264
DOI: 10.1016/j.pharmthera.2023.108435 -
Molecular Cancer Therapeutics Mar 2023Most antibody-drug conjugates (ADC) approved for the treatment of cancer contain protease-cleavable linkers. ADCs that traffic to lysosomes traverse highly acidic late...
Most antibody-drug conjugates (ADC) approved for the treatment of cancer contain protease-cleavable linkers. ADCs that traffic to lysosomes traverse highly acidic late endosomes, while ADCs that recycle to the plasma membrane traffic through mildly acidic sorting and recycling endosomes. Although endosomes have been proposed to process cleavable ADCs, the precise identity of the relevant compartments and their relative contributions to ADC processing remain undefined. Here we show that a METxMET biparatopic antibody internalizes into sorting endosomes, rapidly traffics to recycling endosomes, and slowly reaches late endosomes. In agreement with the current model of ADC trafficking, late endosomes are the primary processing site of MET, EGFR, and prolactin receptor ADCs. Interestingly, recycling endosomes contribute up to 35% processing of the MET and EGFR ADCs in different cancer cells, mediated by cathepsin-L, which localizes to this compartment. Taken together, our findings provide insight into the relationship between transendosomal trafficking and ADC processing and suggest that receptors that traffic through recycling endosomes might be suitable targets for cleavable ADCs.
Topics: Humans; Immunoconjugates; Antibodies; Cancer Vaccines; Endosomes; ErbB Receptors
PubMed: 36861363
DOI: 10.1158/1535-7163.MCT-22-0414