Prolactin and autoimmunity

Prolactin levels and chronic kidney disease and the subsequent risk of cardiovascular events: A long term population based cohort study

Both the clearance and secretion of prolactin are disrupted in chronic kidney disease (CKD). Evidence indicates that prolactin may play a role in cardiovascular (CV) disturbances. Considering the increased cardiovascular risk associated with CKD, this study investigates the relationship between prolactin levels, CKD, and the risk of CV events in both women and men, with an average follow-up period of 20 years. The study included 2,005 participants from the Tehran Lipid and Glucose Study (TLGS) who met the inclusion criteria. They were reassessed approximately every three years for a median follow-up of 19.0 years (Interquartile range (IQR):16.4-20.2), during which occurrences of CKD and CV events were recorded. A pooled logistic regression model examined the influence of Prolactin on CV events and its interaction with CKD. During follow-up, we identified 156 incident cases of CV events among men and 73 among women. Median (95%CI) PRL levels were 7.4 (5.5-10.5) ng/mL for men and 15.2 (10.3-23) ng/mL for women. The results of analyses showed that a history of CKD was associated with significantly higher odds of CV events for both men 4.2 (95% CI: 2.6-6.8) and women 5.5 (95% CI: 2.6-11.5). Results remained unchanged after adjustment for confounders including age, waist circumference, smoking, education, history of diabetes and hypertension, and family history of CV events. Interaction analyses revealed no statistically significant interaction between CKD and PRL on the odds of CV events in unadjusted and adjusted models. This consistent pattern was observed regardless of gender. Results of population-based data with over a median follow-up period of 20 years showed that CKD independently increases the risk of CV events in both men and women. However, our findings suggest that this elevated risk may not be substantially influenced by prolactin levels. Further investigation may be warranted to confirm these findings.

Acquired hypoprolactinemia in men, possible phenotype

The physiological role of prolactin (PRL) in men is still not well defined. The pathological increase is characterized by sexual function impairment along with possible negative consequences in body composition and metabolic profile. Conversely, the clinical significance of reduced PRL levels was only partially investigated or mainly neglected. The present paper aims to summarize and critically discuss possible phenotypes characterizing male subjects with reduced PRL levels. When possible, meta-analytic results were provided. Available data derived from patients seeking medical care for sexual dysfunction as well as from cross-sectional and longitudinal studies showed that low PRL in males is associated with a worse metabolic phenotype (including diabetes mellitus), mood disturbances (including anxiety and depression), and sexual dysfunctions (including psychogenic erectile and ejaculatory dysfunctions). Whether or not these features are direct consequences of reduced PRL levels or whether the latter reflect other pathway impairments such as serotoninergic failure cannot be clarified. The present data, however, emphasize that a deficiency of PRL should be taken into account and need further investigations.

Increased Thoracic Fluid as the Most Distinctive Cardiovascular Hemodynamic Alteration in Men with Prolactinoma

Hyperprolactinemia in males with prolactin-secreting adenomas, or prolactinomas, may be associated with endothelial dysfunction and co-existing cardiovascular risk factors. As a noninvasive technique of assessing cardiac function, impedance cardiography (ICG) may be useful in the early detection of hemodynamic dysfunction. The aim of the present study was to analyze and compare the hemodynamic profiles of patients with prolactinoma versus controls. A total of 20 men with prolactinoma (PR group) (mean age 43 years) and 20 men from the control group (CG) were evaluated in this prospective, observational comparative clinical study. The study subjects were propensity score-matched in terms of clinical characteristics—age, mean blood pressure [MBP], arterial hypertension [AH] rates, and body mass index [BMI]. ICG assessments of hemodynamic profiles were conducted with the use of a Niccomo™ device and included stroke volume index (SI), cardiac index (CI), systemic vascular resistance index (SVRI), velocity index (VI), acceleration index (ACI), Heather index (HI), and thoracic fluid content (TFC). AH was well-controlled in both study groups (116/76 mmHg PR vs. 119/76 mmHg CG). In comparison with CG patients, ICG revealed PR group patients to have higher rates of high thoracic fluid content (TFC) (>35 1/kOhm; p = 0.035) and lower SI values (<35 mL/m2, p = 0.072). There was a convergent tendency towards lower values of other cardiac function parameters (SI, CI, VI, ACI, and HI). Prolactinoma-associated endocrine abnormalities are related to hemodynamic profile alterations, including higher rates of increased TFC and the risk of worsened cardiac function.

The metabolic role of prolactin: systematic review, meta-analysis and preclinical considerations

INTRODUCTION

Hyperprolactinemia has been proven to induce hypogonadism and metabolic derangements in both genders, while the consequences of prolactin (PRL) deficiency have been poorly investigated.

AREAS COVERED

To systematically review and analyze data from clinical studies focusing on the metabolic consequences of abnormally high prolactin levels (HPRL) and low prolactin levels (LPRL). In addition, data from preclinical studies about underlying pathophysiological mechanisms were summarized and discussed.

EXPERT OPINION

PRL contributes to providing the correct amount of energy to support the mother and the fetus/offspring during pregnancy and lactation, but it also has a homeostatic role. Pathological PRL elevation beyond these physiological conditions, but also its reduction, impairs metabolism and body composition in both genders, increasing the risk of diabetes and cardiovascular events. Hence, hypoprolactinemia should be avoided as much as possible during treatment with dopamine agonists for prolactinomas. Patients with hypoprolactinemia, because of endogenous or iatrogenic conditions, deserve, as those with hyperprolactinemia, careful metabolic assessment.

The role of prolactin/vasoinhibins in cardiovascular diseases

Prolactin (PRL) is a polypeptide hormone that is mainly synthesized and secreted by the lactotroph cells of the pituitary. There are two main isoforms of PRL: 23-kDa PRL (named full-length PRL) and vasoinhibins (including 5.6-18 kDa fragments). Both act as circulating hormones and cytokines to stimulate or inhibit vascular formation at different stages and neovascularization, including endothelial cell proliferation and migration, protease production, and apoptosis. However, their effects on vascular function and cardiovascular diseases are different or even contrary. In addition to the structure, secretion regulation, and signal transduction of PRL/vasoinhibins, this review focuses on the pathological mechanism and clinical significance of PRL/vasoinhibins in cardiovascular diseases.

Relationship between styrene exposure and prolactin secretion in human and animal studies: A systematic review

Styrene is widely used in industrial applications. Inhalation exposure occurs in the industry. Some studies indicated that serum prolactin concentrations increased after exposure to styrene, while other studies found no change. In this systematic review, the search was done with the keywords styrene and prolactin in the PubMed, Science Direct, Web of Science and Scopus databases, regardless of the publication period. 118 studies were obtained and only seven articles were finally selected according to exclusion and inclusion criteria. The effect of styrene on prolactin secretion was selected in both human and animal studies. The increased response was seen in inhalation exposures. Subcutaneous exposure has no significant effect on prolactin levels. The observed responses were both dose-dependent and gender-dependent. Changes in serum prolactin were more frequent in women compared to exposed men. Dopamine depletion was not observed in all studies, so more tests on laboratory animals are necessary to clarify the possible mechanism.

The interplay between prolactin and cardiovascular disease

Hyperprolactinemia can be caused by several conditions and its effects on the hypothalamic-pituitary-gonadal axis are understood in more detail. Nevertheless, in recent decades, other metabolic effects have been studied and data pointed to a potential increased cardiovascular disease (CVD) risk. A recent study showed a decrease in total and LDL- cholesterol only in men with prolactinoma treated with dopamine agonists (DA) supporting the previous results of a population study with increased CVD risk in men harboring prolactinoma. However, other population studies did not find a correlation between prolactin (PRL) levels and CVD risk or mortality. There is also data pointing to an increase in high-density lipoprotein levels, and decreases in triglycerides, carotid-intima-media thickness, C-reactive protein, and homocysteine levels in patients with prolactinoma on DA treatment. PRL was also implicated in endothelial dysfunction in pre and postmenopausal women. Withdrawal of DA resulted in negative changes in vascular parameters and an increase in plasma fibrinogen. It has been shown that PRL levels were positively correlated with blood pressure and inversely correlated with dilatation of the brachial artery and insulin sensitivity, increased homocysteine levels, and elevated D-dimer levels. Regarding possible mechanisms for the association between hyperprolactinemia and CVD risk, they include a possible direct effect of PRL, hypogonadism, and even effects of DA treatment, independently of changes in PRL levels. In conclusion, hyperprolactinemia seems to be associated with impaired endothelial function and DA treatment could improve CVD risk. More studies evaluating CVD risk in hyperprolactinemic patients are important to define a potential indication of treatment beyond hypogonadism.

A network pharmacology analysis on drug-like compounds from Ganoderma lucidum for alleviation of atherosclerosis

Ganoderma lucidum (GL) is known as a potent alleviator against chronic inflammatory disease like atherosclerosis (AS), but its mechanisms against AS have not been unveiled. This research aimed to identify the key compounds(s) and mechanism(s) of GL against AS through network pharmacology. The compounds from GL were identified by gas chromatography-mass spectrum (GC-MS), and SwissADME screened their physicochemical properties. Then, the target(s) associated with the screened compound(s) or AS related targets were identified by public databases, and we selected the overlapping targets using a Venn diagram. The networks between overlapping targets and compounds were visualized, constructed, and analyzed by RStudio. Finally, we performed a molecular docking test (MDT) to explore key target(s), compound(s), on AutoDockVina. A total of 35 compounds in GL were detected via GC-MS, and 34 compounds (accepted by Lipinski's rule) were selected as drug-like compounds (DLCs). A total of 34 compounds were connected to the number of 785 targets, and DisGeNET and Online Mendelian Inheritance in Man (OMIM) identified 2,606 AS-related targets. The final 98 overlapping targets were extracted between the compounds-targets and AS-related targets. On Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment, the number of 27 signaling pathways were sorted out, and a hub signaling pathway (MAPK signaling pathway), a core gene (PRKCA), and a key compound (Benzamide, 4-acetyl-N-[2,6-dimethylphenyl]) were selected among the 27 signaling pathways via MDT. Overall, we found that the identified 3 DLCs from GL have potent anti-inflammatory efficacy, improving AS by inactivating the MAPK signaling pathway. PRACTICAL APPLICATIONS: Ganoderma lucidum (GL) has been used as a medicinal or edible mushroom for chronic inflammatory patients: diabetes mellitus and dyslipidemia, especially atherosclerosis (AS). Until now, the majority of mushroom research has been implemented regarding β-glucan derivatives with very hydrophilic physicochemical properties. It implies that β-glucan or its derivatives have poor bioavailability. Hence, we have involved GC-MS in identifying lipophilic compounds from GL, which filtered them in silico to sort drug-like compounds (DLCs). Then, we retrieved targets associated with the DLCs, and identified a key signaling pathway, key targets, and key compounds against AS. In this paper, we utilized bioinformatics and network pharmacology theory to understand the uncovered pharmacological mechanism of GL on AS. To sum things up, our analysis elucidates the relationships between signaling pathways, targets, and compounds in GL. Ultimately, this work provides biochemical evidence to identify the therapeutic effect of GL on AS, and a scientific basis for deciphering the key mechanism on DLCs of GL against AS.

Antipsychotic-induced Hyperprolactinemia in aging populations: Prevalence, implications, prevention and management

This paper reviews the prevalence, implications, prevention and management of antipsychotic-induced hyperprolactinemia in aging populations. Antipsychotics are indicated mainly for the treatment of psychotic illness but are also used in other conditions. Complications induced by antipsychotics increase with age, due to age-related changes in drug metabolism and excretion. Almost all antipsychotics lead to hyperprolactinemia by blocking dopamine D2 receptors in the anterior pituitary gland, which counteracts dopamine's inhibitory action on prolactin secretion. The main findings of this narrative review are that, though many of the known side effects of high prolactin levels lose their salience with age, the risk of exacerbating osteoporosis remains critical. Methods of preventing antipsychotic-induced hyperprolactinemia in older individuals include using antipsychotic medication (AP) as sparingly as possible and monitoring AP serum levels, regularly measuring prolactin levels, closely monitoring bone density, treating substance abuse, and teaching patients stress management techniques. When hyperprolactinemia symptoms cannot be otherwise managed, adjunctive drugs are available. Potential helpful adjuncts are: dopamine agonists, antipsychotics with partial agonist properties (e.g. aripiprazole), selective estrogen receptor modulators, and metformin. Because a gold standard for prevention/treatment has not been established, clinical decisions need to be made based on safety and individual circumstance.

Prolactinomas and menopause: any changes in management?

PURPOSE

Treatment goals in prolactinomas are to correct hypogonadism, restore fertility and control tumor mass in case of macroadenomas. According to current guidelines, medical treatment of asymptomatic postmenopausal women is not indicated. The purpose of this study was to review the current literature pertaining to biological behavior of prolactinomas during menopause, likelihood of successful dopamine agonist withdrawal during this period and possible prolactin-mediated increased morbidity that could modify current management.

METHODS

A comprehensive literature search including papers published until July 2019 was conducted using PubMed and Medline databases.

RESULTS

Women with prolactinomas entering menopause have a higher chance of prolactin normalization of treatment compared with women in their reproductive years. Although most prolactin secreting adenomas diagnosed during menopause are large, they respond well to dopamine agonist treatment. Data directly linking hyperprolactinemia with an increased risk of cancer and cardiovascular and metabolic morbidity are inconsistent. There is no data indicating that correction of hyperprolactinemia improves clinical outcomes in asymptomatic patients bearing microadenomas.

CONCLUSION

There is no evidence that justifies changing current recommendations to withhold medical treatment of microprolactinomas in asymptomatic post-menopausal women. Macroprolactinoma patients should be treated according to standard clinical practice.

The Active Compounds of Yixin Ningshen Tablet and Their Potential Action Mechanism in Treating Coronary Heart Disease- A Network Pharmacology and Proteomics Approach

Yixin Ningshen tablet is a CFDA-approved TCM formula for treating coronary heart disease (CHD) clinically. However, its active compounds and mechanism of action in treating CHD are unknown. In this study, a novel strategy with the combination of network pharmacology and proteomics was proposed to identify the active components of Yixin Ningshen tablet and the mechanism by which they treat CHD. With the application of network pharmacology, 62 active compounds in Yixin Ningshen tablet were screened out by text mining, and their 313 potential target proteins were identified by a tool in SwissTargetPrediction. These data were integrated with known CHD-related proteomics results to predict the most possible targets, which reduced the 313 potential target proteins to 218. The STRING database was retrieved to find the enriched pathways and related diseases of these target proteins, which indicated that the Calcium, MAPK, PI3K-Akt, cAMP, Rap1, AGE-RAGE, Relaxin, HIF-1, Prolactin, Sphingolipid, Estrogen, IL-17, Jak-STAT signaling pathway, necroptosis, arachidonic acid metabolism, insulin resistance, endocrine resistance, and steroid hormone biosynthesis might be the main pathways regulated by Yixin Ningshen tablet for the treatment of CHD. Through further enrichment analysis and literature study, EGFR, ERBB2, VGFR2, FGF1, ESR1, LOX15, PGH2, HMDH, ADRB1, and ADRB2 were selected and then validated to be the target proteins of Yixin Ningshen tablet by molecular docking, which indicated that Yixin Ningshen tablet might treat CHD mainly through promoting heart regeneration, new vessels' formation, and the blood supply of the myocardial region and reducing cardiac output, oxygen demand, and inflammation as well as arteriosclerosis (promoting vasodilation and intraplaque neoangiogenesis, lowering blood lipid). This study is expected to benefit the clinical application of Yixin Ningshen tablet for the treatment of CHD.

Metabolic effects of dopamine agonists in patients with prolactinomas: a systematic review and meta-analysis

OBJECTIVES

Recent large cohort studies suggest an association between high plasma prolactin and cardiovascular mortality. The objective of this systematic review was to systematically assess the effect of reducing prolactin with dopamine agonist on established cardiovascular risk factors in patients with prolactinomas.

DESIGN

Bibliographical search was done until February 2019 searching the following databases: PubMed, EMBASE, WHO and LILAC. Eligible studies had to include participants with verified prolactinomas where metabolic variables were assessed before and after at least 2 weeks treatment with dopamine agonists.

METHODS

Baseline data and outcomes were independently collected by two investigators. The study was registered with PROSPERO (registration number CRD42016046525).

RESULTS

Fourteen observational studies enrolling 387 participants were included. The pooled standardized mean difference of the primary outcome revealed a reduction of BMI and weight of -0.21 (95% CI -0.37 to -0.05; P = 0.01; I2 = 71%), after treatment. Subgroup analysis suggested that the reduction of weight was primarily driven by studies with high prolactin levels at baseline (P = 0.04). Secondary outcomes suggested a small decrease in waist circumference, a small-to-moderate decrease in triglycerides, fasting glucose levels, HOMA-IR, HbA1c and hsCRP, and a moderate decrease in LDL, total cholesterol and insulin.

CONCLUSION

This systematic review suggests a reduction of weight as well as an improved lipid profile and glucose tolerance after treatment with dopamine agonist in patients with prolactinomas. These data are based on low-quality evidence.

Lack of Relationships Between Serum Prolactin Concentrations and Classical Cardiovascular Risk Factors in Eastern Croatian Older Adults

Background

Relationships between serum prolactin concentrations and various CV risk factors in older adults have rarely been assessed. The aim of this study was to examine the relationships between serum prolactin concentrations and CV risk factors in older patients with multiple CV risk factors.

Material/Methods

This case-control study included 92 patients, 50–89 years old (median, 69 years), with multiple CV risk factors. We used data from general practice electronic health records and biochemical laboratory tests. Patients were divided according to categories of CV risk factors.

Results

Serum prolactin concentrations were significantly higher in elderly people (≤65 vs. >65) and in men (70.65±58.02 vs. 150.82±114.05 mIU/L), as well as in patients with lower renal function (156.70±127.23 vs. 72.53±37.25 mIU/L, the bottom vs. top quartile of creatinine clearance), higher serum homocysteine and TSH concentrations, and in those who used NSAID and statins. Parameters indicating chronic inflammation (CRP) and renal function decline (creatinine clearance) were significantly and independently correlated with increased serum prolactin concentrations in multiple regression analysis.

Conclusions

When assessing the relationships between prolactin and CV risk factors in older people with multiple CV risk factors, the effect of renal function decline and chronic inflammation should receive attention.

Integrative gene ontology and network analysis of coronary artery disease associated genes suggests potential role of ErbB pathway gene EGFR

Coronary artery disease (CAD) is a major cause of mortality in India, more importantly the young Indians. Combinatorial and integrative approaches to evaluate pathways and genes to gain an improved understanding and potential biomarkers for risk assessment are required. Therefore, 608 genes from the CADgene database version 2.0, classified into 12 functional classes representing the atherosclerotic disease process, were analyzed. Homology analysis of the unique list of gene ontologies (GO) from each functional class gave 8 GO terms represented in 11 and 10 functional classes. Using disease ontology analysis 80 genes belonging to 8 GO terms, using FunDO suggested that 29 of them were identified to be associated with CAD. Extended network analysis of these genes using STRING version 9.1 gave 328 nodes and 4,525 interactions of which the top 5% had a node degree of ≥75 associated with pathways including the ErbB signaling pathway with epidermal growth factor receptor (EGFR) gene as the central hub. Evaluation of EFGR protein levels in age and gender-matched 342 CAD patients vs. 342 control subjects demonstrated significant differences [controls=149.76±2.47 pg/ml and CAD patients stratified into stable angina (SA)=161.65±3.40 pg/ml and myocardial infarction (MI)=171.51±4.26 pg/ml]. Logistic regression analysis suggested that increased EGFR levels exhibit 3-fold higher risk of CAD [odds ratio (OR) 3.51, 95% confidence interval [CI] 1.96–6.28, P≤0.001], upon adjustment for hypertension, diabetes and smoking. A unit increase in EGFR levels increased the risk by 2-fold for SA (OR 2.58, 95% CI 1.25–5.33, P=0.01) and 3.8-fold for MI (OR 3.82, 95% CI 1.94–7.52, P≤0.001) following adjustment. Thus, the use of ontology mapping and network analysis in an integrative manner aids in the prioritization of biomarkers of complex disease.

Males with prolactinoma are at increased risk of incident cardiovascular disease

OBJECTIVE

To investigate whether the risk of incident cardiovascular disease (CVD) is increased in patients with prolactinoma.

DESIGN

Population-based, retrospective, open-cohort study using The Health Improvement Network (THIN) database.

PATIENTS

A total of 2233 patients with prolactinoma and 10 355 matched controls (1:5 ratio) from UK General Practices contributing to THIN were included. Sex, age, body mass index and smoking status were used as matching parameters. The primary outcome was any incident CVD, defined by Read codes suggesting myocardial infarction, angina pectoris, stroke, transient ischaemic attack or heart failure. Sex-specific-adjusted incidence rate ratios (aIRRs) were calculated with Poisson regression, using clinically relevant parameters as model covariates. Sensitivity analyses were performed to check whether a change in the initial assumptions could have an impact on the findings.

RESULTS

During the 6-year observation period, the composite CVD outcome was recorded in 54 patients with prolactinoma and 180 "nonexposed" individuals. The incidence rate was 1.8 and 14.8 per 1000 person-years for the females and males with prolactinoma, respectively. The aIRRs for CVD were estimated at 0.99 [95% confidence interval (CI): 0.61-1.61, P = .968)] in female patients and 1.94 (95% CI: 1.29-2.91, P = .001) in male patients. These findings remained robust in sensitivity analyses restricting to patients with documented record of dopamine agonist treatment and those with newly diagnosed prolactinoma.

CONCLUSIONS

In contrast to females, men with prolactinoma have increased risk for incident CVD; the aetiology of this gender-specific finding remains to be elucidated.

Differential Regulation of Cardiac Function and Intracardiac Cytokines by Rapamycin in Healthy and Diabetic Rats

Diabetes is comorbid with cardiovascular disease and impaired immunity. Rapamycin improves cardiac functions and extends lifespan by inhibiting the mechanistic target of rapamycin complex 1 (mTORC1). However, in diabetic murine models, Rapamycin elevates hyperglycemia and reduces longevity. Since Rapamycin is an immunosuppressant, we examined whether Rapamycin (750 μg/kg/day) modulates intracardiac cytokines, which affect the cardiac immune response, and cardiac function in male lean (ZL) and diabetic obese Zucker (ZO) rats. Rapamycin suppressed levels of fasting triglycerides, insulin, and uric acid in ZO but increased glucose. Although Rapamycin improved multiple diastolic parameters (E/E′, E′/A′, E/Vp) initially, these improvements were reversed or absent in ZO at the end of treatment, despite suppression of cardiac fibrosis and phosphoSer473Akt. Intracardiac cytokine protein profiling and Ingenuity® Pathway Analysis indicated suppression of intracardiac immune defense in ZO, in response to Rapamycin treatment in both ZO and ZL. Rapamycin increased fibrosis in ZL without increasing phosphoSer473Akt and differentially modulated anti-fibrotic IL-10, IFNγ, and GM-CSF in ZL and ZO. Therefore, fundamental difference in intracardiac host defense between diabetic ZO and healthy ZL, combined with differential regulation of intracardiac cytokines by Rapamycin in ZO and ZL hearts, underlies differential cardiac outcomes of Rapamycin treatment in health and diabetes.

Spanish consensus on the risks and detection of antipsychotic drug-related hyperprolactinaemia

INTRODUCTION

Iatrogenic hyperprolactinaemia (IHPRL) has been more frequently related to some antipsychotic drugs that provoke an intense blockade of dopamine D2 receptors. There is a wide variation in clinical practice, and perhaps some more awareness between clinicians is needed. Due to the high frequency of chronic treatment in severe mental patients, careful attention is recommended on the physical risk. IHPRL symptoms could be underestimated without routine examination.

METHODOLOGY

An intense scientific literature search was performed in order to draw up a multidisciplinary consensus, including different specialists of psychiatry, endocrinology, oncology and internal medicine, and looking for a consensus about clinical risk and detection of IHPRL following evidence-based medicine criteria levels (EBM I- IV).

RESULTS

Short-term symptoms include amenorrhea, galactorrhoea, and sexual dysfunction with decrease of libido and erectile difficulties related to hypogonadism. Medium and long-term symptoms related to oestrogens are observed, including a decrease bone mass density, hypogonadism, early menopause, some types of cancer risk increase (breast and endometrial), cardiovascular risk increase, immune system disorders, lipids, and cognitive dysfunction. Prolactin level, gonadal hormones and vitamin D should be checked in all patients receiving antipsychotics at baseline although early symptoms (amenorrhea-galactorrhoea) may not be observed due to the risk of underestimating other delayed symptoms that may appear in the medium term. Routine examination of sexual dysfunction is recommended due to possible poor patient tolerance and low compliance. Special care is required in children and adolescents, as well as patients with PRL levels >50ng/ml (moderate hyperprolactinaemia). A possible prolactinoma should be investigated in patients with PRL levels >150ng/ml, with special attention to patients with breast/endometrial cancer history. Densitometry should be prescribed for males >50 years old, amenorrhea>6 months, or early menopause to avoid fracture risk.

Association Between Prolactin and Incidence of Cardiovascular Risk Factors in the Framingham Heart Study

BACKGROUND

Prolactin is an anterior pituitary hormone that may modulate the adverse effects of obesity. Prolactin has been associated with cardiovascular disease mortality, but less is known about whether prolactin predicts incidence of cardiovascular disease risk factors.

METHODS AND RESULTS

Our sample (n=3232, mean age 40.4 years, 52.1% women) was drawn from Framingham Heart Study participants who attended 2 examinations an average of 6.1 years apart. After excluding those with elevated prolactin (>30 mg/dL for women, >20 mg/dL for men), multivariable-adjusted regressions modeled the associations between baseline prolactin and changes in cardiovascular disease risk factors. Models were adjusted for age, sex, baseline value of the risk factor, smoking status, hormone replacement therapy, and menopausal status and additionally for body mass index. Mean prolactin levels were 11.9 mg/dL (SD 5.2) in women and 8.0 mg/dL (SD 2.9) in men. No associations were observed for change in weight, body composition, total cholesterol, triglycerides, or fasting glucose. In women, for example, for each 5-mg/dL increment in prolactin, odds of incident hypercholesterolemia were 1.06, which was not significant (95% CI 0.91-1.23, P=0.46). Some exceptions were of note. In women, for each 5-mg/dL increment in prolactin, we observed increased odds of low high-density lipoprotein cholesterol at follow-up (odds ratio 1.50, 95% CI 1.18-1.91, P=0.001) that persisted after adjustment for body mass index (P=0.001). In men, a 5-mg/dL increment in prolactin was associated with increased odds of incident hypertension (odds ratio 1.61, 95% CI 1.18-2.20 P=0.002) and incident diabetes (odds ratio 1.70, 95% CI 1.04-2.78, P=0.03).

CONCLUSIONS

Prolactin is not associated with a comprehensive panel of incident cardiovascular disease risk factors. Measurement of circulating prolactin levels in the community likely does not provide substantial insight into cardiometabolic risk.

Testosterone and gonadotropins but not SHBG vary with CKD stages in young and middle aged men

Background

The aim of this study was to assess the effects chronic kidney disease (CKD) had on sex hormones and lipids in a subgroup of men between 18 and 50 years old with CKD 1–5 stage without diabetes and not treated with hemodialysis.

Methods

Data were collected from 101 men with different CKD stages.

Results

Higher CKD stage (lower function) had a significant negative linear trend on total testosterone level (p < 0.01) and free testosterone level (p < 0.01), with a significant increase of luteinizing hormone (LH) (p < 0.01), and prolactin (p < 0.01), while SHBG remained unchanged between the CKD stages. Triglycerides but not total cholesterol, HDL –cholesterol or LDL-cholesterol increased with higher CKD stage. A negative correlation was observed between BMI, SHBG and free testosterone (p < 0.01 for both) but not with other sex hormones. Age per se was related to a significant decrease of total and free testosterone level (p < 0.01 for both) even after correction for BMI.

Decreased levels of total testosterone and estimated free testosterone levels had a significant correlation with an increased level of triglyceride levels (p <0.01).

Conclusions

Our results indicate that CKD stage per se is a factor affecting testosterone levels in combination with age in men between 18 and 50 years old with CKD 1–5 stage, not treated with hemodialysis.

With increased CKD stage there was a significant increase in LH level and a pattern of hypergonadotropic hypogonadism. SHBG remained unchanged between the CKD stages.

Electronic supplementary material

The online version of this article (doi:10.1186/s12610-015-0027-y) contains supplementary material, which is available to authorized users.

From conception to delivery: managing the pregnant inflammatory bowel disease patient

Inflammatory bowel disease (IBD) typically affects patients during their adolescent and young adult years. As these are the reproductive years, patients and physicians often have concerns regarding the interaction between IBD, medications and surgery used to treat IBD, and reproduction, pregnancy outcomes, and neonatal outcomes. Studies have shown a lack of knowledge among both patients and physicians regarding reproductive issues in IBD. As the literature is constantly expanding regarding these very issues, with this review, we provide a comprehensive, updated overview of the literature on the management of the IBD patient from conception to delivery, and provide action tips to help guide the clinician in the management of the IBD patient during pregnancy.

Is prolactin involved in the evolution of atherothrombotic disease?

Cardiovascular diseases (CVDs) account for approximately 30% of all deaths globally. The most important cause of CVD is atherothrombosis, in other words, narrowing of the arteries as a result of the deposition of cholesterol and other lipoid substances within the arterial wall. Several endocrine disorders have been linked to this pathological state. Recent clinical and experimental studies have suggested that prolactin, a pleiotropic pituitary hormone, may potentially contribute to CVD, either through direct modulation of local cellular processes within atherosclerotic plaques/thrombi and/or through influencing conventional cardiovascular metabolic risk factors. However, the precise role of prolactin in the pathology of CVD remains largely unknown. Here, the authors speculate whether prolactin-lowering treatment may become a future therapeutic approach in patients with elevated prolactin levels and concomitantly presenting with coexisting vascular disease or a significantly elevated risk for premature atherothrombotic vascular disease. Awareness of these new developments may also change our clinical opinions about therapeutic strategies in patients with prolactinomas.

Prolactin levels, endothelial dysfunction, and the risk of cardiovascular events and mortality in patients with CKD

BACKGROUND AND OBJECTIVES

Both prolactin clearance and production are altered in CKD. In nonrenal populations, emerging evidence suggests that prolactin participates in the atherosclerotic process. Given the elevated cardiovascular risk of CKD, this study examined links between prolactinemia, vascular derangements, and outcomes.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

This observational study was conducted in two cohorts: one with 457 nondialyzed CKD patients (mean age 52±12 years; 229 men) with measurements of flow-mediated dilation (FMD) and carotid intima-media thickness and one with 173 hemodialysis patients (65±12 years; 111 men) with measurements of pulse wave velocity (PWV). Patients were followed for cardiovascular events (n=146, nondialyzed cohort) or death (n=79, hemodialysis cohort).

RESULTS

Prolactin levels increased along with reduced kidney function. Prolactin significantly and independently contributed to explain the variance of both FMD (in nondialyzed patients) and PWV (in hemodialysis patients), but not intima-media thickness. In Cox analyses, the risk of cardiovascular events in nondialyzed patients increased by 27% (hazard ratio [HR], 1.27; 95% confidence interval [95% CI], 1.17-1.38) for each 10 ng/ml increment of prolactin. Similarly, the risk for all-cause and cardiovascular mortality in hemodialysis patients increased by 12% (HR, 1.12; 95% CI, 1.06-1.17) and 15% (HR, 1.15; 95% CI, 1.08-1.21), respectively. This was true after multivariate adjustment for confounders and after adjustment within the purported causal pathway (FMD or PWV).

CONCLUSIONS

Prolactin levels directly associated with endothelial dysfunction/stiffness and with increased risk of cardiovascular events and mortality in two independent cohorts of CKD patients.

Most read in cardiovascular genetics on biomarkers, inherited cardiomyopathies and arrhythmias, metabolomics, and genomics

The following articles are being highlighted as part of Circulation: Cardiovascular Genetics' Topic Review series. This series summarizes the most important manuscripts, as selected by the editors, that have been published in Circulation and the Circulation subspecialty journals. The studies included here represent the most-read articles published on the topic of biomarkers, inherited cardiomyopathies and arrhythmias, metabolomics, and genomics in 2009 and 2010.

The association of serum prolactin concentration with inflammatory biomarkers - cross-sectional findings from the population-based Study of Health in Pomerania

OBJECTIVE

Prolactin (PRL) is involved in immune regulation and may contribute to an atherogenic phenotype. Previous results on the association of PRL with inflammatory biomarkers have been conflicting and limited by small patient studies. Therefore, we used data from a large population-based sample to assess the cross-sectional associations between serum PRL concentration and high-sensitivity C-reactive protein (hsCRP), fibrinogen, interleukin-6 (IL-6), and white blood cell (WBC) count.

DESIGN AND POPULATION

From the population-based Study of Health in Pomerania (SHIP), a total of 3744 subjects were available for the present analyses.

METHODS AND MEASUREMENTS

PRL and inflammatory biomarkers were measured. Linear and logistic regression models adjusted for age, sex, body-mass-index, total cholesterol and glucose were analysed.

RESULTS

Multivariable linear regression models revealed a positive association of PRL with WBC. Multivariable logistic regression analyses showed a significant association of PRL with increased IL-6 in non-smokers [highest vs lowest quintile: odds ratio 1·69 (95% confidence interval 1·10-2·58), P = 0·02] and smokers [OR 2·06 (95%-CI 1·10-3·89), P = 0·02]. Similar results were found for WBC in non-smokers [highest vs lowest quintile: OR 2·09 (95%-CI 1·21-3·61), P = 0·01)] but not in smokers. Linear and logistic regression analyses revealed no significant associations of PRL with hsCRP or fibrinogen.

CONCLUSIONS

Serum PRL concentrations are associated with inflammatory biomarkers including IL-6 and WBC, but not hsCRP or fibrinogen. The suggested role of PRL in inflammation needs further investigation in future prospective studies.

Soluble CD40 ligand and prolactin levels in migraine patients during interictal period

The relationship of migraine with cardiovascular diseases has been clarified by many studies, and currently, migraine is suggested to be a systematic vasculopathy. Inflammation, thrombosis and impaired vascular reactivity are the underlying pathophysiological mechanisms of the vasculopathy. In the present study, we aimed to investigate the relationship between prolactin levels and subclinical atherosclerosis risk factors such as soluble CD40 ligand (sCD40L) and high-sensitivity CRP (hsCRP) in migraine patients during interictal period. Fifty female migraine patients and age-matched 25 female control cases were enrolled in the study. Migraine diagnosis was settled according to the ICHD-II diagnostic criteria. A questionnaire was completed about the existence of vascular risk factors. Serum samples were used to measure sCD40L, hsCRP and prolactin levels. No difference was found between the prolactin levels of the migraine patients and the controls. The sCD40L levels were significantly higher in migraine patients (p < 0.001). High-sensitivity CRP levels showed no difference between the groups. There was no correlation between prolactin, sCD40L, and hs-CRP levels in migraine patients. We consider that the migraine patients are prone to subclinical atherosclerosis, but this tendency is independent of prolactin levels.

Pilot study of circulating prolactin levels and endothelial function in men with hypertension

BACKGROUND

Hyperprolactinemia has been recently associated with hypertension and endothelial dysfunction in humans, confirming animal studies performed in the 1970s that showed high prolactin levels to exert positive chronotropic and vasoconstrictive effects. Whether prolactin affects endothelial function, in the absence of hyperprolactinemia, remains unknown. Considering that secretion of prolactin presents circadian rhythmicity, we tested the hypothesis that in patients with hypertension, who present diurnal variation in their endothelial function as well, prolactin levels correlate with endothelial function and/or blood pressure.

METHODS

Endothelial function, assessed by flow-mediated dilatation (FMD) and serum prolactin were examined successively at 12 PM, 9 PM, and 7 AM in 27 nonhyperprolactinemic men with newly diagnosed, untreated essential hypertension.

RESULTS

Both FMD and prolactin presented 24-h variation (P < 0.01). FMD reached its lowest values at 7 AM (2.1 ± 1.8%, mean ± s.d.); concurrently prolactin levels peaked (7.18 ng/ml, median). Across the three time points, prolactin changes inversely interacted with FMD changes (P = 0.002). Systolic and diastolic blood pressure also varied significantly but no interaction with prolactin changes was evident.

CONCLUSIONS

Diurnal fluctuations of prolactin levels are associated with decreased endothelial function that occurs early in the morning in men with hypertension, although this study did not assess causality. Additional studies are required to determine whether these responses differ from normotensive individuals.

Differential action of two prolactin isoforms on ischemia and re-perfusion-induced arrhythmias in rats in vivo

BACKGROUND

The different influences of one of the PRL isoforms (PRL I) on the cardiovascular system have been described in the past.

AIM

Our goal was to establish an appropriate iv dose of 2 PRL isoforms (PRL I and PRL II) in intact rats. After establishing this dose, PRL I (0.01 mg/kg) or PRL II (0.001 mg/kg) was administered in bolus 10 min before left anterior descending coronary artery occlusion (7 min) followed by re-perfusion (15 min). We then aimed to study and compare the effects of these isoforms on ischemia- and re-perfusion-induced arrhythmias in the ischemia and re-perfusion-induced arrhythmias model in rats.

MATERIALS AND METHODS

Mortality index, ventricular fibrillation and tachycardia (VF, VT) incidence and duration, systolic, diastolic, and mean arterial blood pressure, heart rate and myocardial index of oxygen consumption [pressure rate product (PRP)] were measured and calculated.

RESULTS

Both PRL isoforms reduced animal mortality (from 50 to 18.75 and 25%, respectively). PRL II significantly reduced VF incidence (to 25%) as well as VT duration (18.21 ± 3.09) and these effects were markedly different from PRL I and from the control group (p<0.05). Both PRL reduced PRP in the recovery phase (p<0.05).

CONCLUSIONS

We proved that supraphysiological doses of PRL isoforms administered in bolus could protect against sudden cardiac death as well as severe arrhythmias episodes during re-perfusion. Because of PRL's positive influence on the cardiovascular system and as an endogenous, well-tolerated substance, it might be of potential clinical use.

A review of hyperprolactinaemia and severe mental illness: Are there implications for clinical biochemistry?

Hyperprolactinaemia is a common adverse event reported in association with treatments used in schizophrenia and bipolar disorder. Recent data are suggestive that hyperprolactinaemia may have a range of significant short-and long-term clinical consequences. The objective of this review is to examine the causes, frequency and clinical consequences of hyperprolactinaemia in the severely mentally ill (SMI) with a focus on patients taking antipsychotic medications. A Medline search was carried out to identify relevant publications. Reference lists from previous review articles were also examined to search for additional data. Hyperprolactinaemia may be one of the most common adverse events associated with some antipsychotic medications. Precise rates with individual drugs had however until recently been poorly categorized. The relationship between hyperprolactinaemia and adverse outcomes in the SMI population appears similar to that in the general population. Adverse outcomes (such as sexual dysfunction) can occur acutely and in the longer term (bone fractures and possibly breast cancer), but the precise link between degree and length of hyperprolactinaemia and adverse outcome remains to be established. In conclusion, hyperprolactinaemia is a common treatment-emergent adverse event of some antipsychotic medications and may have clinical consequences. Physicians must balance the benefits and risks of treatment when determining appropriate therapy for individual patients.