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Genes & Diseases May 2024
PubMed: 38274369
DOI: 10.1016/j.gendis.2023.06.018 -
Best Practice & Research. Clinical... Feb 2024Cabergoline is an ergot derivative long-acting dopamine receptor 2 (DR2) selective agonist administered orally and widely used for the treatment of prolactin-secreting... (Review)
Review
Cabergoline is an ergot derivative long-acting dopamine receptor 2 (DR2) selective agonist administered orally and widely used for the treatment of prolactin-secreting adenomas and Parkinson's disease. DR2 is expressed in most somatotroph adenomas. In acromegaly, cabergoline is used off-label and its role is limited by the relatively modest efficacy for achieving hormonal remission and thus, it is largely indicated in patients with mild elevation of GH/IGF-I postoperatively. It can be given as monotherapy, usually at a higher weekly dose than usually required to treat prolactinomas, but also as an add-on treatment in patients partially responding to the somatostatin receptor ligands octreotide or lanreotide. IGF-1 normalization with cabergoline can be achieved in about a third of the patients. Low baseline IGF-1 level (below 1.5 x ULN) before cabergoline initiation is a good predictor for remission. Combination treatment with the GH receptor antagonist pegvisomant can also be beneficial. The inexpensive, well-tolerated and convenient oral administration of cabergoline makes it an attractive medical therapy for active acromegaly.
PubMed: 38443225
DOI: 10.1016/j.beem.2024.101887 -
Journal of Zhejiang University.... May 2024The short neuropeptide F (sNPF) family of peptides is a multifunctional group of neurohormones involved in the regulation of various physiological processes in insects.... (Review)
Review
The short neuropeptide F (sNPF) family of peptides is a multifunctional group of neurohormones involved in the regulation of various physiological processes in insects. They have been found in a broad spectrum of species, but the number of isoforms in the precursor molecule varies from one to four. The receptor for sNPF (sNPFR), which belongs to the G protein-coupled receptor family, has been characterized in various insect orders and was shown to be an ortholog of the mammalian prolactin-releasing peptide receptor (PrPR). The sNPF signaling pathway interacts with other neurohormones such as insulin-like peptides, SIFamide, and pigment-dispersing factors (PDFs) to regulate various processes. The main physiological function of sNPF seems to be involved in the regulation of feeding, but the observed effects are species-specific. sNPF is also connected with the regulation of foraging behavior and the olfactory system. The influence of sNPF on feeding and thus energy metabolism may also indirectly affect other vital processes, such as reproduction and development. In addition, these neurohormones are involved in the regulation of locomotor activity and circadian rhythm in insects. This review summarizes the current state of knowledge about the sNPF system in insects.
Topics: Animals; Neuropeptides; Insecta; Signal Transduction; Circadian Rhythm; Feeding Behavior; Receptors, G-Protein-Coupled; Energy Metabolism
PubMed: 38725339
DOI: 10.1631/jzus.B2300355 -
Annals of Medicine and Surgery (2012) Feb 2024Cardiovascular disease (CVD) is the most common cause of morbidity and mortality worldwide. Bromocriptine is a partial antagonist for D1 dopamine receptors while also... (Review)
Review
Cardiovascular disease (CVD) is the most common cause of morbidity and mortality worldwide. Bromocriptine is a partial antagonist for D1 dopamine receptors while also serving as a selective agonist on D2 dopamine receptors as a dopamine receptor agonist. Apart from prolactin inhibiting action, bromocriptine has some beneficial effects on the blood pressure, plasma norepinephrine levels and vascular resistance. Dopamine D2 receptor activation of bromocriptine is associated with the antihypertensive effect, which lowers blood pressure via inhibiting sympathetic nerve activity and Na/K ATPase activity. Plasma levels of the pro-inflammatory cytokines such as interleukin (IL)-1B and IL-18, chemokine CCL2/ MCP-1/, and the pro-inflammatory hormone prolactin, all of which are elevated and linked to accelerated cardiometabolic illness, were decreased because of bromocriptine therapy. The most common side effects of Bromocriptine use are dizziness, nausea, headache, vomiting and hypotension. Bromocriptine is mainly contraindicated in patients with syncope with hypotension, psychosis, and type I diabetes mellitus. The authors suggest that developing therapies directed to increase D2 receptor expression and function by drugs like Bromocriptine can provide practical and novelistic approaches to prevent and manage myocardial and renal injury in the cardiovascular disease patients.
PubMed: 38333315
DOI: 10.1097/MS9.0000000000001642 -
Endocrinology Nov 2023The close association between rheumatoid arthritis (RA), sex, reproductive state, and stress has long linked prolactin (PRL) to disease progression. PRL has both...
The close association between rheumatoid arthritis (RA), sex, reproductive state, and stress has long linked prolactin (PRL) to disease progression. PRL has both proinflammatory and anti-inflammatory outcomes in RA, but responsible mechanisms are not understood. Here, we show that PRL modifies in an opposite manner the proinflammatory actions of IL-1β and TNF-α in mouse synovial fibroblasts in culture. Both IL-1β and TNF-α upregulated the metabolic activity and the expression of proinflammatory factors (Il1b, Inos, and Il6) via the activation of the nuclear factor-κB (NF-κB) signaling pathway. However, IL-1β increased and TNF-α decreased the levels of the long PRL receptor isoform in association with dual actions of PRL on synovial fibroblast inflammatory response. PRL reduced the proinflammatory effect and activation of NF-κB by IL-1β but increased TNF-α-induced inflammation and NF-κB signaling. The double-faceted role of PRL against the 2 cytokines manifested also in vivo. IL-1β or TNF-α with or without PRL were injected into the knee joints of healthy mice, and joint inflammation was monitored after 24 hours. IL-1β and TNF-α increased the joint expression of proinflammatory factors and the infiltration of immune cells. PRL prevented the actions of IL-1β but was either inactive or further increased the proinflammatory effect of TNF-α. We conclude that PRL exerts opposite actions on joint inflammation in males and females that depend on specific proinflammatory cytokines, the level of the PRL receptor, and the activation of NF-κB signaling. Dual actions of PRL may help balance joint inflammation in RA and provide insights for development of new treatments.
Topics: Male; Female; Mice; Animals; Cytokines; NF-kappa B; Tumor Necrosis Factor-alpha; Prolactin; Synovial Membrane; Cells, Cultured; Arthritis, Rheumatoid; Inflammation; Fibroblasts
PubMed: 37864848
DOI: 10.1210/endocr/bqad156 -
Frontiers in Endocrinology 2023While there are reports of treatment-related endocrine disruptions and catecholamine surges in pheochromocytoma/paraganglioma (PPGL) patients treated with...
PURPOSE
While there are reports of treatment-related endocrine disruptions and catecholamine surges in pheochromocytoma/paraganglioma (PPGL) patients treated with [Lu]Lu-DOTA-TATE therapy, the spectrum of these abnormalities in the immediate post-treatment period (within 48 hours) has not been previously evaluated and is likely underestimated.
METHODS
The study population included patients (≥18 years) enrolled in a phase 2 trial for treatment of somatostatin receptor (SSTR)-2+ inoperable/metastatic pheochromocytoma/paraganglioma with [Lu]Lu-DOTA-TATE (7.4 GBq per cycle for 1 - 4 cycles). Hormonal measurements [adrenocorticotropic hormone (ACTH), cortisol, thyroid stimulating hormone (TSH), free thyroxine (FT4), follicle stimulating hormone (FSH), luteinizing hormone (LH), testosterone, estradiol, growth hormone, prolactin], catecholamines, and metanephrines were obtained on days-1, 2, 3, 30, and 60 per cycle as per trial protocol, and were retrospectively analyzed.
RESULTS
Among the 27 patients (age: 54 ± 12.7 years, 48.1% females) who underwent hormonal evaluation, hypoprolactinemia (14.1%), elevated FSH (13.1%), and elevated LH (12.5%) were the most frequent hormonal abnormalities across all 4 cycles combined. On longitudinal follow-up, significant reductions were noted in i. ACTH without corresponding changes in cortisol, ii. TSH, and FT4, and iii. prolactin at or before day-30 of [Lu]Lu-DOTA-TATE. No significant changes were observed in the gonadotropic axis and GH levels. Levels of all hormones on day-60 were not significantly different from day-1 values, suggesting the transient nature of these changes. However, two patients developed clinical, persistent endocrinopathies (primary hypothyroidism: n=1 male; early menopause: n=1 female). Compared to day-1, a significant % increase in norepinephrine, dopamine, and normetanephrine levels were noted at 24 hours following [Lu]Lu-DOTA-TATE dose and peaked within 48 hours.
CONCLUSIONS
[Lu]Lu-DOTA-TATE therapy is associated with alterations in endocrine function likely from radiation exposure to SSTR2+ endocrine tissues. However, these changes may sometimes manifest as clinically significant endocrinopathies. It is therefore important to periodically assess endocrine function during [Lu]Lu-DOTA-TATE therapy, especially among symptomatic patients.
CLINICAL TRIAL REGISTRATION
https://clinicaltrials.gov/ct2/show/NCT03206060?term=NCT03206060&draw=2&rank=1, identifier NCT03206060.
Topics: Humans; Male; Female; Adult; Middle Aged; Aged; Pheochromocytoma; Retrospective Studies; Prolactin; Hydrocortisone; Adrenal Gland Neoplasms; Adrenocorticotropic Hormone; Follicle Stimulating Hormone; Catecholamines; Thyrotropin
PubMed: 37886645
DOI: 10.3389/fendo.2023.1275813 -
Medicina (Kaunas, Lithuania) Jun 2024Hyperprolactinemia, as a potential side-effect of some antipsychotic medications, is associated with decreased bone density and an increased risk of fractures. This...
Hyperprolactinemia, as a potential side-effect of some antipsychotic medications, is associated with decreased bone density and an increased risk of fractures. This study investigates whether calcium and vitamin D supplementation affects prolactin receptor ( gene expression in the duodenum, vertebrae, and kidneys of female rats with sulpiride-induced hyperprolactinemia. Twenty-one-week-old female Wistar rats were assigned to three groups: Group S consisted of ten rats who received sulpiride injections (10 mg/kg) twice daily for 6 weeks; Group D (10 rats) received daily supplementation of 50 mg calcium and 500 IU vitamin D along with sulpiride for the last 3 weeks; and Group C consisting of seven age-matched nulliparous rats serving as a control group. Real-time PCR was used to assess gene expression in the duodenum, vertebrae, and kidneys. In Group S, Prlr gene expression was notably decreased in the duodenum ( < 0.01) but elevated in the vertebrae and kidneys compared to Group C. Conversely, Group D exhibited significantly increased Prlr expression in the duodenum ( < 0.01) alongside elevated expression in the vertebrae and kidneys. In sulpiride-induced hyperprolactinemia, decreased Prlr gene expression in the duodenum may lead to reduced intestinal calcium absorption. Consequently, prolactin may draw calcium from the skeletal system to maintain calcium balance, facilitated by increased Prlr gene expression in the vertebrae. However, vitamin D supplementation in sulpiride-induced hyperprolactinemia notably enhances Prlr gene expression in the duodenum, potentially ameliorating intestinal calcium absorption and mitigating adverse effects on bone health.
Topics: Animals; Hyperprolactinemia; Sulpiride; Rats, Wistar; Female; Vitamin D; Rats; Calcium; Duodenum; Receptors, Prolactin; Gene Expression
PubMed: 38929559
DOI: 10.3390/medicina60060942 -
Scientific Reports Oct 2023We evaluated whether the administration of kisspeptin-10 (Kp10) is capable of restoring gonadal function in hypothyroid male rats. Hypothyroidism was induced with...
We evaluated whether the administration of kisspeptin-10 (Kp10) is capable of restoring gonadal function in hypothyroid male rats. Hypothyroidism was induced with 6-propyl-2-thiouracil (PTU) for three months. In the last month, half of the hypothyroid animals were treated with Kp10. Hypothyroidism reduced testicular and sex gland mass, decreased the proliferation of the seminiferous epithelium, and compromised sperm morphology, motility, and vigor. A decrease in plasma LH and testosterone levels and an increase in prolactin secretion were observed in the hypothyroid rats. Hypothyroidism reduced Kiss1 and Kiss1r protein and gene expression and Star and Cyp11a1 mRNA levels in the testis. Furthermore, it reduced Lhb, Prl, and Drd2 and increased Tshb and Gnrhr expression in the pituitary. In the hypothalamus, hypothyroidism increased Pdyn and Kiss1r while reducing Gnrh1. Kp10 treatment in hypothyroid rats restored testicular and seminal vesicle morphology, improved sperm morphology and motility, reversed high prolactin levels, and increased LH and testosterone levels. In addition, Kp10 increased testicular expression of Kiss1, Kiss1r, Fshr, and Nr5a1 and pituitary Kiss1 expression. Our findings describe the inhibitory effects of hypothyroidism on the male gonadal axis and sperm quality and demonstrate that Kp10 treatment reverses high prolactin levels and improves gonadal function and sperm quality in hypothyroid rats.
Topics: Rats; Animals; Male; Kisspeptins; Prolactin; Luteinizing Hormone; Receptors, Kisspeptin-1; Semen; Hypothyroidism; Testis; Testosterone
PubMed: 37798396
DOI: 10.1038/s41598-023-44056-z -
Journal of Alzheimer's Disease Reports 2023Neurological disorders, such as Alzheimer's disease (AD), comprise a major cause of health-related disabilities in human. However, biomarkers towards pathogenesis or...
BACKGROUND
Neurological disorders, such as Alzheimer's disease (AD), comprise a major cause of health-related disabilities in human. However, biomarkers towards pathogenesis or novel targets are still limited.
OBJECTIVE
To identify the causality between plasma proteins and the risk of AD and other eight common neurological diseases using a Mendelian randomization (MR) study.
METHODS
Exposure data were obtained from a genome-wide association study (GWAS) of 2,994 plasma proteins in 3,301 healthy adults, and outcome datasets included GWAS summary statistics of nine neurological disorders. Inverse variance-weighted MR method as the primary analysis was used to estimate causal effects.
RESULTS
Higher genetically proxied plasma myeloid cell surface antigen CD33 level was found to be associated with increased risk of AD (odds ratio [OR] 1.079, 95% confidence interval [CI] 1.047-1.112, = 8.39×10). We also discovered the causality between genetically proxied elevated prolactin and higher risk of epilepsy (OR = 1.068, 95% CI = 1.034-1.102; = 5.46×10). Negative associations were identified between cyclin-dependent kinase 8 and ischemic stroke (OR = 0.927, 95% CI = 0.896-0.959, = 9.32×10), between neuralized E3 ubiquitin-protein ligase 1 and migraine (OR = 0.914, 95% CI = 0.878-0.952, = 1.48×10), and between Fc receptor-like protein 4 and multiple sclerosis (MS) (OR = 0.929, 95% CI = 0.897-0.963, = 4.27×10).
CONCLUSION
The findings identified MR-level protein-disease associations for AD, epilepsy, ischemic stroke, migraine, and MS.
PubMed: 37662610
DOI: 10.3233/ADR-230058 -
International Journal of Molecular... Dec 2023Tuberoinfundibular dopamine (TIDA) neurons have cell bodies located in the arcuate nucleus of the mediobasal hypothalamus. They project to the external zone of the... (Review)
Review
Tuberoinfundibular dopamine (TIDA) neurons have cell bodies located in the arcuate nucleus of the mediobasal hypothalamus. They project to the external zone of the median eminence, and the dopamine (DA) released there is carried by the hypophysial portal vasculature to the anterior pituitary. The DA then activates D2 receptors to inhibit prolactin (PRL) secretion from lactotrophs. The TIDA neuronal population is the principal regulatory factor controlling PRL secretion. The neuroendocrine role subserved by TIDA neurons sets them apart from other dopaminergic populations like the nigrostriatal and mesolimbic DA neurons. TIDA neurons exhibit intrinsic oscillatory fluctuations in their membrane potential that give rise to phasic firing and bursting activity. TIDA neuronal activity is sexually differentiated and modulated by gonadal hormones and PRL, as well as an array of small molecule and peptide neurotransmitters. This review covers these characteristics.
Topics: Dopamine; Dopaminergic Neurons; Arcuate Nucleus of Hypothalamus; Cell Communication; Cell Differentiation
PubMed: 38203281
DOI: 10.3390/ijms25010110