Pituitary hormones and immune function

The role of hormones in the regulation of lactogenic immunity in porcine and bovine species

Colostrum and milk offer a complete diet and vital immune protection for newborn mammals with developing immune systems. High immunoglobulin levels in colostrum serve as the primary antibody source for newborn piglets and calves. Subsequent milk feeding support continued local antibody protection against enteric pathogens, as well as maturation of the developing immune system and provide nutrients for newborn growth. Mammals have evolved hormonal strategies that modulate the levels of immunoglobulins in colostrum and milk to facilitate effective lactational immunity. In addition, hormones regulate the gut-mammary gland-secretory immunoglobulin A (sIgA) axis in pregnant mammals, controlling the levels of sIgA in milk, which serves as the primary source of IgA for piglets and helps them resist pathogens such as PEDV and TGEV. In the present study, we review the existing studies on the interactions between hormones and the gut-mammary-sIgA axis/lactogenic immunity in mammals and explore the potential mechanisms of hormonal regulation that have not been studied in detail, to draw attention to the role of hormones in influencing the immune response of pregnant and lactating mammals and their offspring, and highlight the effect of hormones in regulating sIgA-mediated anti-infection processes in colostrum and milk. Discussion of the relationship between hormones and lactogenic immunity may lead to a better way of improving lactogenic immunity by determining a better injection time and developing new vaccines.

The Impact of Obesity on the Host-Pathogen Interaction with Influenza Viruses - Novel Insights: Narrative Review

After exposure to a viral pathogen, the host-pathogen interaction is essential to determine whether or not infection will ensue, and what the clinical outline of the infection will be. Recent research has shown that the patient with obesity presents a set of particular pathophysiological changes that lead to higher severity of viral infections, and this is particularly true for infection with influenza viruses. Herein, we describe the main metabolic, endocrine, and immune dysregulations that occur in the presence of obesity and their impact on driving intra-host viral diversity, leading to heightened severity and virulence of influenza. We show that obesity is linked to modified responses of both the innate and adaptive immune systems during viral infections, including influenza. Due to chronic inflammation and metabolic, endocrine, and signaling pathway disruptions, individuals with obesity have a suboptimal immune response. This results in longer illness duration, increased virus shedding, higher risk of hospitalization and complications, and greater mortality rates. Additionally, they may have a blunted response to vaccination and a higher likelihood of genetic mutation selection. Understanding the intricate interplay between obesity and viral pathogenesis is crucial for developing efficacious therapeutic approaches and public health policies, particularly in light of the escalating worldwide incidence of obesity.

The Association between Somatotropin Therapy and the Risk of SARS-CoV-2 Infection in Children with Short Stature: A Population-Based Cross-Sectional Study

COVID-19 is a worldwide pandemic caused by SARS-CoV-2, to which adults are usually more susceptible than children. Growth hormone (GH) levels differ between children and adults and decrease with age. There is bidirectional crosstalk between the GH/insulin-like growth factor-1 (IGF-1) pathway and the immune system that plays a significant role in SARS-CoV-2 infection. We evaluated the association between somatotropin treatment (GH replacement therapy) and the risk for SARS-CoV-2 positivity (a marker for COVID-19 infection) in children with growth hormone issues (GHI): growth hormone deficiency (GHD) and idiopathic short stature (ISS). A population-based cross-sectional study in Leumit Health Services (LHS) was performed using the electronic health record (EHR) database. The rates of SARS-CoV-2 positivity were evaluated among children with GHI, treated or untreated with somatotropin. Higher rates of SARS-CoV-2 positivity were found in GHI children, influenced by the same confounders reported in the pediatric population. A lower prevalence of SARS-CoV-2 PCR positivity was found among the somatotropin-treated children. A multivariate analysis documented that somatotropin treatment was associated with a reduced risk of SARS-CoV-2 positivity (Odds Ratio (OR) = 0.47, Confidence Interval (CI) 0.24-0.94, p = 0.032). Thus, somatotropin might be a protective factor against SARS-CoV-2 infections, possibly related to its immunomodulatory activity.

Biomarker-assisted assessment of aquatic health using the cosmopolitan common carp, Cyprinus carpio (L): a case study of bisphenol-A exposures

Monitoring aquatic health from environmental pollutants is critical, none more so than bisphenol-A (BPA), a ubiquitous endocrine-disrupting chemical (EDC). The present study brings out the responses of selected transcripts, hormone levels, and tissue histomorphology in a widely distributed fish species Cyprinus carpio (Linn.), following exposure to environmentally relevant (10, 100 ng/L) and higher (1000 ng/L) concentration of BPA. The response of cyp19a1a, cyp19a1b, and c3 significantly decreased, while that of vtg increased in their respective tissue domains. The hematological parameters TEC, Hb, and Hct decreased significantly in contrast to TLC (p < 0.05) at all exposure concentrations, whereas none of the erythrocytic indices (MCV, MCH, and MCHC) was perturbed. The steroidogenic hormone levels, such as estradiol and progesterone, increased significantly with increasing BPA concentrations. In contrast, the testosterone and all the thyroid hormones (T₃, T₄, and TSH) were suppressed significantly (p < 0.05). At the histological level, the BPA induced chondrocyte proliferation, which was accompanied by hemorrhage of the gill lamellae, increased melanomacrophagic centers (MMCs), and degeneration of tubules and fluid accumulation in the kidney. In parallel, binucleated hepatocytes and inflammations were prominent in the liver. Collectively, the histomorphology confirmed induction of degenerative effects in all the tissues investigated, while the cyclic responses of biochemical markers suggest an ability to regulate the impacts. However, a chronic exposure could result in overriding the endemic reproductive pathways with potential population-level effects. In conclusion, the study identified multiple molecular, cellular, and physiological markers that could be employed to detect early signs of BPA and more broadly EDC exposures. These markers in combination with a wide distribution of C. carpio should allow comparative studies of pollutants at environmental concentrations.

Research Progress on the Mechanism of the Acupuncture Regulating Neuro-Endocrine-Immune Network System

As one of the conventional treatment methods, acupuncture is an indispensable component of Traditional Chinese Medicine. Currently, acupuncture has been partly accepted throughout the world, but the mechanism of acupuncture is still unclear. Since the theory of the neuro-endocrine-immune network was put forward, new insights have been brought into the understanding of the mechanism of acupuncture. Studies have proven that acupuncture is a mechanical stimulus that can activate local cell functions and neuroreceptors. It also regulates the release of related biomolecules (peptide hormones, lipid hormones, neuromodulators and neurotransmitters, and other small and large biomolecules) in the microenvironment, where they can affect each other and further activate the neuroendocrine-immune network to achieve holistic regulation. Recently, growing efforts have been made in the research on the mechanism of acupuncture. Some researchers have transitioned from studying the mechanism of acupuncture as a single linear pathway to using systems approaches, including metabolomics, genomics, proteomics and biological pathway analysis. This review summarizes the research progress on the neuro-endocrine-immune network related mechanism of acupuncture and discusses its current challenges and future directions.

Dual Mechanisms of Metabolism and Gene Expression of the CCRF-CEM Leukemia Cells under Glucocorticoid Treatment

BACKGROUND

Glucocorticoids play an essential part in anti-leukemic therapies, but resistance is a crucial event for the prognosis of the disease. Glucocorticoids influence the metabolic properties of leukemic cells. The inherent plasticity of clinically evolving cancer cells justifies the characterization of drug-induced early oncogenic pathways, which represent a likely source of detrimental secondary effects.

AIM

The present work aims to investigate the effect of glucocorticoids in metabolic pathways in the CCRF-CEM leukemic cells. Metabolic factors and gene expression profiles were examined in order to unravel the possible mechanisms of the CCRF-CEM leukemic cell growth dynamics.

METHODS

CCRF-CEM cells were used as a model. Cells were treated with prednisolone with concentrations 0-700 μM. Cell culture supernatants were used for glucose, lactic acid, LDH, Na⁺, K⁺ and Ca⁺⁺ measurements. Cytotoxicity was determined with flow cytometry. Microarray analysis was performed using two different chips of 1.2 k and 4.8 k genes. Gene Ontology enrichment analysis was applied to find metabolism- and GC-related genes.

RESULTS

Higher prednisolone concentrations inhibited glucose uptake, without exhibiting any cytotoxic effects. Glucose consumption did not correlate with the total cell population, or the viable population, indicating that growth is not directly proportional to glucose consumption. Neither of the subpopulations, i.e., viable, necrotic, or apoptotic cells, contributed to this.

CONCLUSIONS

Different types of leukemic cells seem to exhibit different patterns of glucose metabolism. Both resistant and sensitive CCRF-CEM cells followed the aerobic pathway of glycolysis. There is probably a rapid change in membrane permeability, causing a general shutdown towards everything that is outside the cell. This could in part also explain the observed resistance. Glucocorticoids do not enter the cell passively anymore and therefore no effects are observed. Based on our observations, ion concentrations are measurable factors both in vitro and in vivo, which makes them possible markers of glucocorticoid cytotoxic action.

Neuronal regulation of immunity: why, how and where?

Neuroimmunology is one of the fastest-growing fields in the life sciences, and for good reason; it fills the gap between two principal systems of the organism, the nervous system and the immune system. Although both systems affect each other through bidirectional interactions, we focus here on one direction - the effects of the nervous system on immunity. First, we ask why is it beneficial to allow the nervous system any control over immunity? We evaluate the potential benefits to the immune system that arise by taking advantage of some of the brain's unique features, such as its capacity to integrate and synchronize physiological functions, its predictive capacity and its speed of response. Second, we explore how the brain communicates with the peripheral immune system, with a focus on the endocrine, sympathetic, parasympathetic, sensory and meningeal lymphatic systems. Finally, we examine where in the brain this immune information is processed and regulated. We chart a partial map of brain regions that may be relevant for brain-immune system communication, our goal being to introduce a conceptual framework for formulating new hypotheses to study these interactions.

Rearing environment affects the genetic architecture and plasticity of DNA methylation in Chinook salmon

Genetic architecture and phenotypic plasticity are important considerations when studying trait variation within and among populations. Since environmental change can induce shifts in the genetic architecture and plasticity of traits, it is important to consider both genetic and environmental sources of phenotypic variation. While there is overwhelming evidence for environmental effects on phenotype, the underlying mechanisms are less clear. Variation in DNA methylation is a potential mechanism mediating environmental effects on phenotype due to its sensitivity to environmental stimuli, transgenerational inheritance, and influences on transcription. To characterize the effect of environment on methylation, we created two 6 × 6 (North Carolina II) Chinook salmon breeding crosses and reared the offspring in two environments: uniform hatchery tanks and seminatural stream channels. We sampled the fish twice during development, at the alevin (larval) and fry (juvenile) stages. We measured DNA methylation at 13 genes using a PCR-based bisulfite sequencing protocol. The genetic architecture of DNA methylation differed between rearing environments, with greater additive and nonadditive genetic variance in hatchery fish and greater maternal effects in seminatural channel fish, though gene-specific variation was evident. We observed plasticity in methylation across all assayed genes, as well as gene-specific effects at two genes in alevin and six genes in fry, indicating developmental stage-specific effects of rearing environment on methylation. Characterizing genetic and environmental influences on methylation is critical for future studies on DNA methylation as a potential mechanism for acclimation and adaptation.

Blood hormones and torque teno virus in peripheral blood mononuclear cells

Men and women respond differently to infectious diseases. Women show less morbidity and mortality, partially due to the differences in sex hormone levels which can influence the immune response. Torque teno virus (TTV) is non-pathogenic and ubiquitously present in serum from a large proportion (up to 90%) of adult humans with virus levels correlating with the status of the host immune response. The source of TTV replication is unknown, but T-lymphocytes have been proposed. In this study we investigated the presence and levels of TTV in peripheral blood mononuclear cells (PBMCs) in premenopausal (pre-MP) women, post-menopausal (post-MP) women, and men, and determined their serum sex hormone levels. Of the examined subjects (n = 27), we found presence of TTV in PMBC from 17.6% pre-MP (n = 17), 25.0% post-MP (n = 4) and 50.0% men (n = 6). The levels of TTV/μg DNA were lower among TTV-positive men and post-MP women compared to pre-MP women. All the positive pre-MP women were either anovulatory, hypothyroid, or both. In addition, the TTV-positive pre-MP women had significantly lower progesterone levels compared to TTV-negative pre-MP women. Although our study was performed on a limited number of subjects, the data suggests that TTV in PBMC is associated with an anovulatory menstrual cycle with low progesterone levels, and possibly with male sex.

The Microenvironment of Pituitary Tumors-Biological and Therapeutic Implications

The tumor microenvironment (TME) includes resident and infiltrative non-tumor cells, as well as blood and lymph vessels, extracellular matrix molecules, and numerous soluble factors, such as cytokines and chemokines. While the TME is now considered to be a prognostic tool and a therapeutic target for many cancers, little is known about its composition in pituitary tumors. This review summarizes our current knowledge of the TME within pituitary tumors and the strong interest in TME as a therapeutic target. While we cover the importance of angiogenesis and immune infiltrating cells, we also address the role of the elusive folliculostellate cells, the emerging literature on pituitary tumor-associated fibroblasts, and the contribution of extracellular matrix components in these tumors. The cases of human pituitary tumors treated with TME-targeting therapies are reviewed and emerging concepts of vascular normalization and combined therapies are presented. Together, this snapshot overview of the current literature pinpoints not only the underestimated role of TME components in pituitary tumor biology, but also the major promise it may offer for both prognosis and targeted therapeutics.

Aromatic hydrocarbon receptors in the immune system: Review and hypotheses

Ah-receptors (AhRs) recognize and bind foreign environmental molecules as well as some target hormones of other nuclear receptors. As ligands activate transcription factors, they transmit the information on the presence of these molecules by binding to the DNA, which in turn activate xenobiotic metabolism genes. Cross talk with other nuclear receptors or some non-nuclear receptors also activates or inhibits endocrine processes. Immune cells have AhRs by which they are activated for physiological (immunity) or non-physiological (allergy and autoimmunity) processes. They can be imprinted by hormonal or pseudo-hormonal (environmental) factors, which could provoke pathological alterations for life (by faulty perinatal hormonal imprinting). The variety and amount of human-made new environmental molecules (endocrine disruptors) are enormously growing, so the importance of AhR functions is also expanding.

Precision Medicine: The Role of the MSIDS Model in Defining, Diagnosing, and Treating Chronic Lyme Disease/Post Treatment Lyme Disease Syndrome and Other Chronic Illness: Part 2

We present a precision medical perspective to assist in the definition, diagnosis, and management of Post Treatment Lyme Disease Syndrome (PTLDS)/chronic Lyme disease. PTLDS represents a small subset of patients treated for an erythema migrans (EM) rash with persistent or recurrent symptoms and functional decline. The larger population with chronic Lyme disease is less understood and well defined. Multiple Systemic Infectious Disease Syndrome (MSIDS) is a multifactorial model for treating chronic disease(s), which identifies up to 16 overlapping sources of inflammation and their downstream effects. A patient symptom survey and a retrospective chart review of 200 patients was therefore performed on those patients with chronic Lyme disease/PTLDS to identify those variables on the MSIDS model with the greatest potential effect on regaining health. Results indicate that dapsone combination therapy decreased the severity of eight major Lyme symptoms, and multiple sources of inflammation (other infections, immune dysfunction, autoimmunity, food allergies/sensitivities, leaky gut, mineral deficiencies, environmental toxins with detoxification problems, and sleep disorders) along with downstream effects of inflammation may all affect chronic symptomatology. In part two of our observational study and review paper, we postulate that the use of this model can represent an important and needed paradigm shift in the diagnosis and treatment of chronic disease.

Stress, mindfulness, and the allergic patient

INTRODUCTION

The global incidence and prevalence of allergic diseases are increasing as is the intensity and duration of excessive psychological stress due to multiple factors associated with living in today's world such as personal, social and political unrest, increased fear and anxiety, and/or depression often leading to hopelessness. Both allergy and chronic psychological stress are characterized by immune imbalances that have similar characteristics. Thus, it is reasonable to posit that the two are interactive and stress may induce as well as complicate at least some allergic diseases. Areas covered: Stress management/reduction has been proposed with various physical, pharmacological, and psychological interventions for both preventive and therapeutic reasons. A useful intervention involves mindfulness techniques, which allow the individual to put their life situation in context for better personal management. Expert commentary: Future studies must be developed that will further examine the role of excess psychological stress in specific allergic diseases and evaluate the effectiveness of various stress intervention protocols, particularly those involving mindfulness, to determine which individual would best respond clinically to which intervention. When this is accomplished, assessment and treatment of psychological stress will become a standard component of clinical care for allergy, asthma, and other immune-based diseases.

Curcumin as a potential protective compound against cardiac diseases

Curcumin, which was first used 3000 years ago as an anti-inflammatory agent, is a well-known bioactive compound derived from the active ingredient of turmeric (Curcuma longa). Previous research has demonstrated that curcumin has immense therapeutic potential in a variety of diseases via anti-oxidative, anti-apoptotic, and anti-inflammatory pathways. Cardiac diseases are the leading cause of mortality worldwide and cause considerable harm to human beings. Numerous studies have suggested that curcumin exerts a protective role in the human body whereas its actions in cardiac diseases remain elusive and poorly understood. On the basis of the current evidence, we first give a brief introduction of cardiac diseases and curcumin, especially regarding the effects of curcumin in embryonic heart development. Secondly, we analyze the basic roles of curcumin in pathways that are dysregulated in cardiac diseases, including oxidative stress, apoptosis, and inflammation. Thirdly, actions of curcumin in different cardiac diseases will be discussed, as will relevant clinical trials. Eventually, we would like to discuss the existing controversial opinions and provide a detailed analysis followed by the remaining obstacles, advancement, and further prospects of the clinical application of curcumin. The information compiled here may serve as a comprehensive reference of the protective effects of curcumin in the heart, which is significant to the further research and design of curcumin analogs as therapeutic options for cardiac diseases.

Energetics and the immune system: Trade-offs associated with non-acute levels of CRP in adolescent Gambian girls

Background and objectives: The human immune system is an ever-changing composition of innumerable cells and proteins, continually ready to respond to pathogens or insults. The cost of maintaining this state of immunological readiness is rarely considered. In this paper we aim to discern a cost to non-acute immune function by investigating how low levels of C-reactive protein (CRP) relate to other energetic demands and resources in adolescent Gambian girls.

Methodology: Data from a longitudinal study of 66 adolescent girls was used to test hypotheses around investment in immune function. Non-acute (under 2 mg/L) CRP was used as an index of immune function. Predictor variables include linear height velocity, adiposity, leptin, and measures of energy balance.

Results: Non-acute log CRP was positively associated with adiposity (β = 0.16, P < 0.001, R² = 0.17) and levels of the adipokine leptin (β = 1.17, P = 0.006, R² = 0.09). CRP was also negatively associated with increased investment in growth, as measured by height velocity (β = −0.58, P < 0.001, R² = 0.13) and lean mass deposition β = −0.42, P = 0.005, R² = 0.08). Relationships between adiposity and growth explained some, but not all, of this association. We do not find that CRP was related to energy balance.

Conclusions and implications: These data support a hypothesis that investment in non-acute immune function is facultative, and sensitive to energetic resources and demands. We also find support for an adaptive association between the immune system and adipose tissue.

Immunoendocrinology: faulty hormonal imprinting in the immune system

Hormonal imprinting is an epigenetic process which is taking place perinatally at the first encounter between the developing hormone receptors and their target hormones. The hormonal imprinting influences the binding capacity of receptors, the hormone synthesis of the cells, and other hormonally regulated functions, as sexual behavior, aggressivity, empathy, etc. However, during the critical period, when the window for imprinting is open, molecules similar to the physiological imprinters as synthetic hormone analogs, other members of the hormone families, environmental pollutants, etc. can cause faulty imprinting with life-long consequences. The developing immune system, the cells of which also have receptors for hormones, is very sensitive to faulty imprinting, which causes alterations in the antibody and cytokine production, in the ratio of immune cells, in the defense against bacterial and viral infections as well as against malignant tumors. Immune cells (lymphocytes, monocytes, granulocytes and mast cells) are also producing hormones which are secreted into the blood circulation as well as are transported locally (packed transport). This process is also disturbed by faulty imprinting. As immune cells are differentiating during the whole life, faulty imprinting could develop any time, however, the most decisive is the perinatal imprinting. The faulty imprinting is inherited to the progenies in general and especially in the case of immune system. In our modern world the number and amount of artificial imprinters (e.g. endocrine disruptors and drugs) are enormously increasing. The effects of the faulty imprinters most dangerous to the immune system are shown in the paper. The present and future consequences of the flood of faulty imprintings are unpredictable however, it is discussed.

Lymphocyte GH-axis hormones in immunity

The production and utilization of common ligands and their receptors by cells of the immune and neuroendocrine systems constitutes a biochemical information circuit between and within the immune and neuroendocrine systems. The sharing of ligands and receptors allows the immune system to serve as the sixth sense notifying the nervous system of the presence of foreign entities. Within this framework, it is also clear that immune cell functions can be altered by neuroendocrine hormones and that cells of the immune system have the ability to produce neuroendocrine hormones. This review summarizes a part of this knowledge with particular emphasis on growth hormone (GH). The past two decades have uncovered a lot of detail about the actions of GH, acting through its receptor, at the molecular and cellular level and its influence on the immune system. The production and action of immune cell-derived GH is less well developed although its important role in immunity is also slowly emerging. Here we discuss the production of GH, GH-releasing hormone (GHRH) and insulin-like growth factor-1 (IGF-1) and their cognate receptors on cells of the immune system and their influence via endocrine/autocrine/paracrine and intracrine pathways on immune function. The intracellular mechanisms of action of immune cell-derived GH are still largely unexplored, and it is anticipated that further work in this particular area will establish an important role for this source of GH in normal physiology and in pathologic situations.

Lymphocyte subpopulations in Sheehan's syndrome

The role of autoimmunity in the development of Sheehan's syndrome is obscure. There are a limited number of studies investigating the immunological alterations accompanying Sheehan's Syndrome. Our objective was to evaluate lymphocyte subsets in these patients. We conducted a cross-sectional clinical study. Cytofluorometry was used for the immunophenotyping of peripheral blood leukocytes from patients with Sheehan's syndrome followed up in the endocrine clinic during 2005-2009. Fifteen consecutive patients (mean age 61.6 ± 11.3, range 34-75 years) and 25 healthy controls (mean age 56.7 ± 10.6, range 34-80 years) were included. There was no statistically significant difference between the groups in terms of mean age. The percentages of CD19(+), CD16(+)/56(+), CD8(+)28(-), γδTCR(+), CD8(+); the total lymphocyte counts; and the ratio of CD8(+)28(-)/CD8(+)28(+) were similar (p > 0.05) between patients and controls. Whereas the leucocyte counts (p = 0.003), the percentage of CD3 (+) DR (+) (p < 0.001), CD8(+)28(+) (p = 0.030), CD4(+)CD25(+) (p = 0.007), the ratio of CD3 (+) DR(+)/CD3 (p < 0.001) were higher; the percentage of CD3 (p = 0.020), CD4 (p < 0.001) and the ratio of CD4/CD8 (p = 0.006) were lower in patients with Sheehan's syndrome compared to healthy controls. There was a positive correlation between the duration of illness and the percentage of CD3(+)DR(+) (r = 0.53, p = 0.03) expression. Some peripheral lymphocyte cell subsets show marked variation in patients with Sheehan's syndrome in comparison to matched healthy subjects, which may have implications for altered immune regulation in these patients. High CD3 (+) DR (+) expression that correlates with the duration of illness in Sheehan's patients is suggestive of an ongoing inflammation accompanying the slow progression of pituitary dysfunction in Sheehan's syndrome. It is not clear if these cellular alterations contribute to the cause or consequence of pituitary deficiency in Sheehan's syndrome.

Reproductive experience modifies dopaminergic function, serum levels of prolactin, and macrophage activity in female rats

Reproductive experience (RE), i.e. pregnancy and lactation, induces physiological changes in mammals. Recent data show that neuroimmune interactions are modulated by a diversity of events involving neurotransmitters and neuropeptides. These molecules, particularly dopamine (DA), were reported to mediate the relevant cross talk between immune and neuroendocrine systems. Moreover, DA-mediated regulation of leukocyte function is a reasonable approach to investigate the DA-operated regulatory switch for immune-competent cells, such as macrophages. Therefore, the goals of the present study were to determine the effects of RE on: (1) dopaminergic function through hypothalamic levels of DA, dihydroxyphenylacetic acid (DOPAC), homovanilic acid (HVA), serotonin (5-HT), and 5-hydroxyindole acetic acid (5-HIAA); (2) basal levels of circulating prolactin (PRL); and (3) activity of peritoneal macrophage (phagocytosis and oxidative burst). A total of 16 adult (200-250 g) female Wistar rats were used, divided in two groups: nulliparous and primiparous. Approximately 2-3 weeks after weaning pups from the primiparous group, both groups of rats were tested. The findings indicate that: (1) DOPAC concentrations, DOPAC/DA and HVA+DOPAC/DA ratios decreased in primiparous rats as compared to virgin rats, (2) primiparous rats showed significantly lower serum PRL levels, and (3) phorbol miristate acetate (PMA)-induced oxidative burst was decreased in peritoneal macrophage from primiparous rats as compared to virgin rats. To test the possible positive correlation between serum levels of PRL and the intensity of oxidative burst by peritoneal macrophage, an extra experiment was done with adult virgin female rats treated with domperidone, an antagonist of DA receptors. Domperidone-treated animals showed increased serum levels of PRL and simultaneous increase in peritoneal macrophage oxidative burst. Thus, suggesting an indirect participation of hyperprolactinemia, induced by this treatment in peritoneal macrophage activity of female rats. These results suggest that a previous RE can modulate the activity of dopaminergic hypothalamic systems, while decreasing PRL serum levels and the oxidative burst of peritoneal macrophage. The neurochemical and hormonal RE-induced changes correlate with the immune alterations.

Experimental rodent models of prostatitis: limitations and potential

Prostatitis is a polyetiological inflammation of the prostate gland in men characterized by pelvic pain, irritative voiding symptoms, and sexual dysfunction. Histologically prostatitis is characterized by poly- and mononuclear cell infiltrates (neutrophils, lymphocytes, macrophages and plasma cells) in the stromal connective tissue around the acini or ducts. Prostatitis is an important worldwide health problem in men. The pathogenesis and diagnostic criteria for the condition are obscure, with the result that the development of management programs for this condition has been hindered. Animal model(s) might be useful in elucidating mechanisms involved in the molecular pathogenesis of chronic nonbacterial prostatitis and chronic pelvic pain syndrome. Given that prostatitis might have a multifactorial etiology, several animal models with unique features may prove helpful. This review examines a number of experimental rodent models of prostatitis and evaluates their advantages and limitations.

Neural-endocrine-immune complex in the central modulation of tumorigenesis: facts, assumptions, and hypotheses

For the precise coordination of systemic functions, the nervous system uses a variety of peripherally and centrally localized receptors, which transmit information from internal and external environments to the central nervous system. Tight interconnections between the immune, nervous, and endocrine systems provide a base for monitoring and consequent modulation of immune system functions by the brain and vice versa. The immune system plays an important role in tumorigenesis. On the basis of rich interconnections between the immune, nervous and endocrine systems, the possibility that the brain may be informed about tumorigenesis is discussed in this review article. Moreover, the eventual modulation of tumorigenesis by central nervous system is also considered. Prospective consequences of the interactions between tumor and brain for diagnosis and therapy of cancer are emphasized.

Dopamine affects cellular immune functions during polymicrobial sepsis

OBJECTIVE

To determine whether infusion of dopamine modulates cellular immune functions and survival during systemic inflammation.

DESIGN AND SETTING

Randomized animal study, university research laboratory, Level I trauma center.

SUBJECTS

Male NMRI mice.

INTERVENTIONS

Mice were subjected to laparotomy (sham intervention, LAP) or polymicrobial sepsis induced by cecal ligation and puncture (CLP). Mice in each of these conditions received either an intraperitoneal infusion of 0.9% saline (CLP/saline; LAP/saline) or an intraperitoneal infusion of dopamine (1.0 microg/kg/min i.p., CLP/DOP; LAP/DOP). Metabolic data and survival were monitored 24 h and 48 h after onset of sepsis, and animals were terminated 48 h after induction of sepsis to determine splenocyte apoptosis (Annexin V binding capacity), splenocyte proliferation (3H-Thymidine incorporation assay), splenocyte IL-2, IL-6 and IFN-gamma release (ELISA) and leukocyte distribution (WBC; CD3, CD4, CD8, B220, F4/80, NK1.1).

MEASUREMENTS AND RESULTS

Infusion of dopamine in septic mice increased splenocyte apoptosis and decreased splenocyte proliferation and IL-2 release of septic mice. Furthermore, an inhibitory effect of dopamine infusion on splenocyte proliferation and the release of the TH1-cytokines IL-2 and IFN-gamma was observed in sham operated control mice. These effects were paralleled by a decreased survival of dopamine-treated septic animals (47% vs. 67%). Treatment with DOP did not affect sepsis-induced changes of leukocyte distribution.

CONCLUSIONS

We conclude that dopamine is capable of modulating cellular immune functions in a murine model of sepsis.

The neuroendocrine stress response and severity of acute respiratory syncytial virus bronchiolitis in infancy

OBJECTIVE

Neuroendocrine hormones have profound effects on the immune system. The immune response is a major factor in the pathogenesis of acute respiratory syncytial virus (RSV) infection. We hypothesised that there is a relationship between the neuroendocrine response in acute RSV infection, the severity of illness, and the degree of lymphopenia.

DESIGN

Prospective, non-randomised cohort study of infants hospitalised for RSV infection requiring mechanical ventilation or managed conservatively. The study assessed the effect of age, gender, birth gestation, and severity of illness on stress hormone profile and its relationship to lymphocyte count.

SETTING

Regional Paediatric Intensive Care Unit (PICU) and children's wards.

PATIENTS

Thirty-two consecutive infants with RSV infection were enrolled, of which thirteen were mechanically ventilated on PICU (study subjects) and nineteen treated on the ward (comparison group). Twenty-three children (72%) returned for follow-up.

MEASUREMENTS AND MAIN RESULTS

A specific neuroendocrine profile was found in PICU patients compared to ward patients (Wilks Lambda = 0.36, F = 9.05, P =.03). PICU patients had significantly higher prolactin and growth hormone, and significantly lower leptin and IGF-1. Cortisol levels were the same. PICU patients were more lymphopenic compared to ward patients (P =.0001). On multiple regression analysis, prolactin and leptin levels accounted for 57% of the variation in lymphocyte count.

CONCLUSIONS

Whereas the effect of intensive care (mechanical ventilation and medication) could not be controlled for, our results suggest that there is an association between the neuroendocrine hormone response, severity of illness and degree of lymphopenia.

Prolactin modulates survival and cellular immune functions in septic mice

BACKGROUND

The immunomodulatory properties of the pituitary hormone prolactin have been demonstrated. It was proposed that prolactin is important in maintaining normal immune response in several pathological states. We investigated the effect of prolactin administration on the survival and cellular immune functions during systemic inflammation.

MATERIALS AND METHODS

Male NMRI mice were subjected to laparotomy (LAP) or sepsis induced by cecal ligation and puncture (CLP). Mice were treated with either saline (LAP/saline; CLP/saline) or prolactin (LAP/PRL, CLP/RPL; 4 mg/kg s.c.). Survival of septic mice was determined 24 and 48 h after CLP. Forty-eight hours after the septic challenge, the proliferative capacity, cytokine release (IL-2, IL-6, IFN-gamma) and apoptosis of splenocytes were determined. Additionally, monitoring of circulating leukocyte distribution was performed (WBC; CD3+, CD4+, CD8+, B220+, NK1.1+, F4/80+ cells by FASCan).

RESULTS

CLP was accompanied by a mortality of 47% and induced a decrease in splenocyte proliferation and apoptosis rate. Administration of prolactin significantly increased the mortality of septic mice (81%). This was paralleled by a further decrease of splenocyte proliferation and an increased splenocyte apoptosis. In addition, administration of prolactin augmented the sepsis-induced inhibition of IL-2 release, attenuated the sepsis-induced inhibition of IFN-gamma release, and did not affect the release of IL-6. However, prolactin did not affect the sepsis-induced changes of circulating leukocyte subpopulations.

CONCLUSIONS

We conclude that prolactin has profound immunomodulatory properties and that administration of prolactin in pharmacological doses is associated with a decreased survival and an inhibition of cellular immune functions in septic mice.

Maternal prolactin composition can permanently affect epidermal gammadeltaT cell function in the offspring

There have been few studies aimed at determining the effects of maternal peptide hormones on the developing fetus and even fewer aimed at determining the long-term consequences of abnormalities in maternal hormone exposure. In this study, we have examined the effect of maternal prolactin (PRL) on the production, seeding and long-term function of a T lymphocyte subset for which the precursors are only present during fetal life. Using this system, we can determine long-term consequences of maternal hormone exposure without concern for the subsequent influence of the offspring's endocrine milieu. Recombinant versions of the two major forms of the pituitary hormone, PRL, were administered to rats throughout pregnancy. Administration of a molecular mimic of phosphorylated PRL (PP-PRL) resulted in a marked increase in the level of apoptosis in the thymus of newborn pups, an effect that was not duplicated by administration of unmodified PRL. The increased thymic apoptosis in the animals exposed to PP-PRL resulted in decreased epidermal seeding of gammadeltaT cells and a markedly decreased gammadeltaT cell-modulated epidermal response in the offspring. This decreased gammadeltaT cell modulated response persisted to adulthood. We conclude that maternal PRL composition during pregnancy can have a permanent effect on at least one component of the developing immune system.

Upregulation of IFN-gamma and soluble interleukin-2 receptor release and altered serum cortisol and prolactin concentration during general anesthesia

The effects of surgery, surgical stress, and anesthesia compromise the optimal function of the immune system. Recent studies demonstrate the influence of anesthesia on the immune response by modulation of neural-immune interactions. To evaluate the immunologic effects of general anesthesia with the hypnotic agent propofol and the opioid fentanyl, two drugs used frequently in anesthesia, we studied 30 patients undergoing elective orthopedic surgery before and during narcosis. We found a significant enhancement of interferon-gamma (IFN-gamma) and soluble interleukin-2 receptor (sIL-2R) release in lipopolysaccharide (LPS)-stimulated whole blood cultures after induction of anesthesia. Similar results were observed in cultures stimulated with polyclonal T cell activators, such as staphylococcal enterotoxin B (SEB) and phytohemagglutinin (PHA). IL-1beta and IL-8 release was not affected, but the anti-inflammatory cytokine IL-10 decreased after skin incision. Serum prolactin significantly increased immediately after induction of anesthesia, whereas serum cortisol levels declined. Our results point to enhanced proinflammatory T lymphocyte and natural killer (NK) cell activity, probably caused by prolactin and cortisol modulation in the serum. This may disturb the balance of human proinflammatory and anti-inflammatory pathways during surgery and general anesthesia.

High frequency of serious infections in patients with panhypopituitarism: a case-control study

We reviewed the records of 65 patients with panhypopituitarism (PHP) for the frequency and types of infections requiring hospitalization, and documented serious infections in 13 of 65 patients with PHP. The increased frequency of serious infectious diseases in patients with PHP is likely to contribute to increased age-specific mortality.

Bromocriptine restores tolerance in estrogen-treated mice

Estrogen can modulate autoimmunity in certain models of systemic lupus erythematosus. Recently, we have shown that it can mediate survival and activation of anti-DNA B cells in a mouse transgenic for the heavy chain of a pathogenic anti-DNA antibody. To identify whether estrogen effects reflect increased prolactin secretion, we characterized B-cell autoreactivity in transgenic mice given both bromocriptine (an inhibitor of prolactin secretion) and estradiol. Treatment of mice with estradiol plus bromocriptine led to reduced titers of anti-DNA antibodies and diminished IgG deposition in kidneys compared with treatment with estradiol alone. However, mice treated with estradiol plus bromocriptine showed an expansion of transgene-expressing B cells and enhanced Bcl-2 expression, similar to those of estradiol-treated mice. We identified anergic high-affinity anti-DNA B cells in mice treated with estradiol plus bromocriptine, and we showed by molecular analysis of anti-DNA hybridomas that their B cells derive from a naive repertoire. Thus, the estradiol-induced breakdown in B-cell tolerance can be abrogated by bromocriptine, which induces anergy in the high-affinity DNA-reactive B cells. These studies demonstrate that some of the effects of estrogen on naive autoreactive B cells require the presence of prolactin and, thus, suggest potential therapeutic interventions in lupus.

Modulation of the inflammatory reaction and neutrophil defense of the bovine lactating mammary gland by growth hormone

This review is focused on the possible interactions of prolactin and somatotrope hormone in the modulation of inflammation of the mammary gland. Several different models are examined: Escherichia coli, Streptococcus uberis, and endotoxin mastitis. Subsequently, the release of growth hormone and insulin-like growth factor during fever and mastitis, the immunophysiological effects of GH on E. coli mastitis, S. uberis and endotoxin mastitis, the galactopoietic action of rBST on healthy and mastitis cows as well as the immunologic effects of GH on leukocytes in healthy and diseased cows are discussed. It can be concluded that the underlying regulation of the neuro-endocrine network is fundamental in the normal function of the immune system.