Steering the Microbiota-Gut-Brain Axis by Antibiotics to Model Neuro-Immune-Endocrine Disorders.

BACKGROUND: Over the last century, animal models have been employed to study the gut-brain axis and its relationship with physiological processes, including those necessary for survival, such as food intake and thermoregulation; those involved in diseases, ranging from inflammation to obesity; and those concerning the development of neurodegenerative diseases and neuropsychiatric disorders, such as Alzheimer's disease and autism spectrum disorder, respectively. SUMMARY: The gut microbiota has been recognized in the last decade as an essential functional component of this axis. Many reports demonstrate that the gut microbiota influences the development of a vast array of physiological processes. Experiments that use animal models to assess the effect of the gut microbiota on the brain and behavior may involve the acute or chronic administration of broad-spectrum antibiotics. KEY MESSAGES: This narrative review summarizes the beneficial or detrimental effects of antibiotics administered prenatally or postnatally to rodents during acute or chronic periods in a wide range of protocols. These include animal models of disease and behavioral paradigms of learning and memory, anxiety, obsessive-compulsive disorder, and autism spectrum disorder. Biomarkers and behavioral assays associated with antibiotic exposure are also included in this review.

Autoimmune Endocrinopathies: An Emerging Complication of Immune Checkpoint Inhibitors.

Immune checkpoint inhibitors (CPIs) reverse immune suppression that is thought to allow malignant growth. Despite remarkable efficacy in a subset of cancers, their use is accompanied by immune-related adverse events, including endocrinopathies such as hypophysitis, thyroid dysfunction, diabetes, and adrenalitis. These conditions are heterogenous, with differing incidence across CPI types, but are unified by the acuity and extremity of tissue-specific organ failure. Their occurrence may be associated with beneficial tumor control. Further understanding of the risk factors and mechanisms of these endocrine immunotoxicities can help optimize CPI use as well as improve understanding of spontaneous autoimmune diseases.

The Kynurenine Pathway-New Linkage between Innate and Adaptive Immunity in Autoimmune Endocrinopathies.

The kynurenine pathway (KP) is highly regulated in the immune system, where it promotes immunosuppression in response to infection or inflammation. Indoleamine 2,3-dioxygenase 1 (IDO1), the main enzyme of KP, has a broad spectrum of activity on immune cells regulation, controlling the balance between stimulation and suppression of the immune system at sites of local inflammation, relevant to a wide range of autoimmune and inflammatory diseases. Various autoimmune diseases, among them endocrinopathies, have been identified to date, but despite significant progress in their diagnosis and treatment, they are still associated with significant complications, morbidity, and mortality. The precise cellular and molecular mechanisms leading to the onset and development of autoimmune disease remain poorly clarified so far. In breaking of tolerance, the cells of the innate immunity provide a decisive microenvironment that regulates immune cells' differentiation, leading to activation of adaptive immunity. The current review provided a comprehensive presentation of the known role of IDO1 and KP activation in the regulation of the innate and adaptive arms of the immune system. Significant attention has been paid to the immunoregulatory role of IDO1 in the most prevalent, organ-specific autoimmune endocrinopathies-type 1 diabetes mellitus (T1DM) and autoimmune thyroiditis.

Multiplex Autoantibody Detection in Patients with Autoimmune Polyglandular Syndromes.

The diagnosis of autoimmune polyglandular syndrome (APS) types 1/2 is difficult due to their rarity and nonspecific clinical manifestations. APS-1 development can be identified with assays for autoantibodies against cytokines, and APS-2 development with organ-specific antibodies. In this study, a microarray-based multiplex assay was proposed for simultaneous detection of both organ-specific (anti-21-OH, anti-GAD-65, anti-IA2, anti-ICA, anti-TG, and anti-TPO) and APS-1-specific (anti-IFN-ω, anti-IFN-α-2a, and anti-IL-22) autoantibodies. Herein, 206 serum samples from adult patients with APS-1, APS-2, isolated autoimmune endocrine pathologies or non-autoimmune endocrine pathologies and from healthy donors were analyzed. The prevalence of autoantibodies differed among the groups of healthy donors and patients with non-, mono- and multi-endocrine diseases. APS-1 patients were characterized by the presence of at least two specific autoantibodies (specificity 99.5%, sensitivity 100%). Furthermore, in 16 of the 18 patients, the APS-1 assay revealed triple positivity for autoantibodies against IFN-ω, IFN-α-2a and IL-22 (specificity 100%, sensitivity 88.9%). No anti-cytokine autoantibodies were found in the group of patients with non-APS-1 polyendocrine autoimmunity. The accuracy of the microarray-based assay compared to ELISA for organ-specific autoantibodies was 88.8-97.6%. This multiplex assay can be part of the strategy for diagnosing and predicting the development of APS.

Immunotoxicity from checkpoint inhibitor therapy: clinical features and underlying mechanisms.

Immune checkpoint inhibition with monoclonal antibodies is becoming increasingly commonplace in cancer medicine, having contributed to a widening of therapeutic options across oncological indications. Disruption of immune tolerance is the key mechanism of action of checkpoint inhibitors and although immune-related adverse events are a typical class effect of these compounds, the relationship between toxicity and response is not fully understood. Awareness and vigilance are paramount in recognizing potentially life-threatening toxicities and managing them in a timely manner. In this review article, we provide an overview of the clinical features, pathological findings and management principles of common immune-related toxicities, attempting to provide mechanistic insight into an increasingly common complication of cancer therapy.

Gut microbiota and metabolites in the pathogenesis of endocrine disease.

Type 1 diabetes (T1D) and Hashimoto's thyroiditis (HT) are the two most common autoimmune endocrine diseases that have rising global incidence. These diseases are caused by the immune-mediated destruction of hormone-producing endocrine cells, pancreatic beta cells and thyroid follicular cells, respectively. Both genetic predisposition and environmental factors govern the onset of T1D and HT. Recent evidence strongly suggests that the intestinal microbiota plays a role in accelerating or preventing disease progression depending on the compositional and functional profile of the gut bacterial communities. Accumulating evidence points towards the interplay between the disruption of gut microbial homeostasis (dysbiosis) and the breakdown of host immune tolerance at the onset of both diseases. In this review, we will summarize the major recent findings about the microbiome alterations associated with T1D and HT, and the connection of these changes to disease states. Furthermore, we will discuss the potential mechanisms by which gut microbial dysbiosis modulates the course of the disease, including disruption of intestinal barrier integrity and microbial production of immunomodulatory metabolites. The aim of this review is to provide broad insight into the role of gut microbiome in the pathophysiology of these diseases.

New era of therapy for endocrine autoimmune disorders.

The new era of immune and reconstitution therapy of autoimmune disorders is ongoing. However, endocrine autoimmune diseases comprise a group of elaborating pathologies where the development of new treatment strategies remains slow. Substitution of the missing hormones is still standard practice, taking care of the devastating symptoms but not the cause of disease. As our knowledge of the genetic contribution to the aetiology of endocrine disorders increases and early diagnostic tools are available, it is now possible to identify persons at risk before they acquire full-blown disease. This review summarizes current knowledge and treatment of endocrine autoimmune disorders, focusing on type 1 diabetes, Addison's disease, autoimmune thyroid diseases and primary ovarian insufficiency. We explore which new therapies might be used in the different stages of the disease, focus on legalized therapy and elaborate on the ongoing clinical studies for these diseases and the research front, before hypothesizing on the way ahead.

Itching as a systemic disease.

Pruritus is a sensation that emanates from the skin and is transferred through peripheral nerve fibers to the central nervous system. It is easily understood that primary skin disorders, such as atopic eczema, skin dryness, psoriasis, and urticaria, can elicit pruritus. However, certain systemic diseases can cause chronic pruritus, which has a significant effect on the patient's quality of life. In this rostrum we provide an overview of the characteristics, pathophysiology, and mechanisms of pruritus of major systemic underlying diseases, including end-stage renal disease, cholestatic liver disease, endocrine/metabolic diseases, and hematologic/lymphoproliferative diseases.

[Justification of the need to normalize vitamin D status for immunoprophylaxis].

Currently, there is an increase in the resistance of microorganisms to the available arsenal of antimicrobial drugs, which makes it necessary to maintain and stimulate the body's own immune-protective properties. The main extraskeletal effect of vitamin D activity is associated with the homeostasis of the immune system. The role of vitamin D in reducing the risk of infection with infectious agents has been studied for a long time. Literature search on the effective use of vitamin D for immunoprophylaxis was carried out in Scopus, Web of Science, PubMed, clinicaltrials.gov databases over the past 10 years for related keywords: vitamin D, immunoprophylaxis. Vitamin D stimulates the synthesis of antimicrobial peptides, cathelicidins and defensins, which exhibit broad-spectrum activity against viruses, bacteria and fungal infections; reduces the concentration of pro-inflammatory cytokines; increases the concentration of anti-inflammatory cytokines. Vitamin D is also involved in cell differentiation, maturation and proliferation of immune cells. The article presents the literature review in order to justify additional intake of vitamin D in case of diagnosis of its deficiency and insufficiency for the purpose of immunoprophylaxis in children and adults, especially in risk groups (elderly age, pregnant women, patients with chronic diseases of respiratory, endocrine and urinary systems, gastrointestinal tract, and infectious diseases). Inclusion of vitamin D in the diet as a dietary supplement, as well as fortification of products with it, can be an effective measure to reduce the risk of both morbidity and mortality, especially during the period of quarantine measures.

Clinical features and autoimmune associations in patients presenting with Idiopathic Isolated ACTH deficiency.

OBJECTIVE: Idiopathic Isolated ATCH deficiency (IIAD) is a rare cause of secondary adrenal insufficiency. As the condition is rare, and the diagnostic criteria ill-defined, there are few good clinical descriptions in the literature. We have described presenting features, autoimmune associations, natural history and responses to CRF, in a large case series of patients presenting with IIAD. DESIGN: This is a retrospective case note analysis with data derived from the recently commenced National Pituitary Database of Ireland. PATIENTS: Twenty-three patients with isolated ACTH deficiency were identified. A thorough chart and biochemistry review was performed. RESULTS: Twenty-three patients were examined (18 women and 5 men). Age at presentation ranged from 17 to 88 years, (median 48 years). Most patients complained of fatigue; 9 patients presented with hyponatraemia, 13 had autoimmune illnesses (primary hypothyroidism, n = 9). CRF stimulation testing was available in 12 of the 23 patients, 5 of whom demonstrated a rise in plasma ACTH concentrations, indicating hypothalamic, rather than pituitary aetiology. Two patients recovered ACTH secretion, and 2 patients progressed to have other pituitary hormone deficiencies. CONCLUSIONS: IIAD typically presents with insidious symptoms. Euvolaemic hyponatraemia is common at diagnosis. It is associated with autoimmune diseases, particularly primary hypothyroidism. As two patients recovered ACTH secretion, and two progressed to other pituitary hormone deficits, repeat pituitary testing should be considered, to identify recovery of function, or progression to other hormone deficits.

[Endocrine complications in primary immunodeficiency diseases]. / Endokrin szövodmények primer immundeficientiában.

Experimental and clinical data suggest a complex interaction between the endocrine and immune systems. However, only few epidemiological studies are available dealing with endocrine complications in different types of primary immunodeficiency diseases. It is well documented that there is a close association between immunodeficiency syndromes and the development of autoimmune disorders. Most of the endocrine dysfunctions are caused mainly by immune dysregulation and autoimmunity like in APECED (autoimmune polyendocrinopathy, candidiasis, ectodermal dystrophy) and IPEX (immune dysregulation, polyendocrinopathy, enteropathy, X-linked) syndromes. In these disorders, an immunologically mediated destructive process by autoreactive T cells damages multiple endocrine organs like the thyroid, parathyroid, adrenal cortex and endocrine pancreas. In some other forms of immunodeficiencies, like Di George syndrome, endocrine disturbances are mainly caused by the underlying genetic disorders but autoimmunity may also take part in the process. The aim of this paper is to give an overview of the different forms of endocrine disturbances and their pathological background in APECED and IPEX syndromes, Di George syndrome and ataxia telangiectasia. Orv Hetil. 2018; 159(49): 2065-2072.

Isolated ACTH deficiency probably induced by autoimmune-related mechanism evoked with nivolumab.

Nivolumab, an anti-programmed death-1 antibody, is a breakthrough treatment for several malignancies. Its specific adverse effects caused by autoimmunity are termed immune-related adverse events, which involve several endocrine dysfunctions. Herein, we report two cases of isolated adrenocorticotropic hormone (ACTH) deficiency induced by nivolumab for the treatment of metastatic malignant melanoma. Case 1 was a 39-year-old man and Case 2 was a 50-year-old woman, both of whom presented with progressive melanoma. After 13 courses of nivolumab administration, both cases were diagnosed with adrenal insufficiency. Despite their basal serum ACTH and cortisol levels being low with little response to corticotropin-releasing hormone loading, other anterior pituitary hormone levels were preserved. Based on these endocrinological data, isolated ACTH deficiency was diagnosed. Magnetic resonance imaging showed normal pituitary glands, excluding hypophysitis. Finally, hydrocortisone replacement enabled the patients to continue nivolumab treatment. Therefore, it is important to consider isolated ACTH syndrome as a possible and potentially severe immune-related adverse event of nivolumab, even when head magnetic resonance imaging of affected cases does not show enlargement. We should not misdiagnose hidden immune-related adverse events behind general complaints of malignancies such as general malaise and appetite loss, to allow successful treatment using this beneficial immune checkpoint inhibitor.

Endocrinological side-effects of immune checkpoint inhibitors.

PURPOSE OF REVIEW: Three mAbs targeting immune checkpoint proteins are available for the treatment of patients with melanoma, lung, and kidney cancer, and their use will likely expand in the future to additional tumor types. We here update the literature on the incidence and pathophysiology of endocrine toxicities induced by these agents, and discuss management guidance. RECENT FINDINGS: Immune checkpoint inhibition may trigger autoimmune syndromes involving different organs, including several endocrine glands (pituitary, thyroid, adrenals, and endocrine pancreas). Hypophysitis is more frequently associated with ipilimumab, whereas the incidence of thyroid dysfunction is higher with nivolumab/pembrolizumab. Primary adrenal insufficiency can rarely occur with either treatment. Autoimmune diabetes is very rare. As hypophysitis and adrenalitis may be life-threatening, endocrinological evaluation is essential particularly in patients developing fatigue and other symptoms consistent with adrenal insufficiency. Corticosteroids should be promptly used when hypophysitis-induced adrenal insufficiency or adrenalitis are diagnosed, but not in thyroiditis or diabetes. No impact of corticosteroids on the efficacy/activity of immune checkpoint-inhibiting drugs is reported. Hormonal deficiencies are often permanent. SUMMARY: In absence of predicting factors, accurate information to patients provided by the oncology care team is essential for early diagnosis and to limit the consequences of checkpoint inhibition-related endocrine toxicity.

Skeletal muscle as a gene regulatory endocrine organ.

PURPOSE OF REVIEW: Skeletal muscle is gaining increased attention as an endocrine organ. Recently, novel myokines and new effects of already established myokines have been identified. The objective of this review is to give an update on the recent advances in the field. RECENT FINDINGS: Several hundred putative myokines have been described, some of which are induced by contraction and differentially regulated between healthy and metabolically diseased individuals. Interleukin-6 (IL-6) is the prototype myokine, which was identified as a muscle-derived cytokine 15 years ago. Recently, IL-6 has been linked to ß-cell survival and inhibition of cancer-cell growth. Moreover, trans-signaling appears to determine whether IL-6 acts as a proinflammatory or an anti-inflammatory cytokine. Irisin has been shown to be a secreted myokine, which contribute to circulating concentrations dependent on training status. IL-15 has been established as a cytokine mediating cross-talk between skeletal muscle and skin tissue, and decorin has been characterized as a contraction-induced myokine which apparently is differentially regulated between healthy and dysglycemic individuals. SUMMARY: Skeletal muscle is an endocrine organ which, by the release of myokines, may influence metabolism in virtually all organs in the body. This knowledge may potentially open up for the possibility of designing new drugs that mimic the effects of myokine signaling.

Obesity and tumor growth: inflammation, immunity, and the role of a ketogenic diet.

PURPOSE OF REVIEW: This article reviews the impact the obese state has on malignancy through inflammation and immune dysregulation using recent excerpts from the medical literature. RECENT FINDINGS: The obese state creates a proinflammatory endocrinologic milieu altering cellular signaling between adipocytes, immunologic cells, and epithelial cells, leading to the over-activation of adipose tissue macrophages and the upregulation of compounds associated with carcinogenesis. Obesity correlates with a deficiency in numerous immunologic cells, including dendritic cells, natural killer cells, and T cells. In part, this can be attributed to a recent finding of leptin receptor expression on these immune cells and the upregulation of leptin signaling in the obese state. A number of clinical trials have demonstrated the feasibility of a high-fat, low-carbohydrate diet as an adjuvant treatment for cancer, and current trials are investigating the impact of this intervention on disease outcomes. In preclinical trials, a ketogenic diet has been shown to impede tumor growth in a variety of cancers through anti-angiogenic, anti-inflammatory, and proapoptotic mechanisms. SUMMARY: Obesity is becoming more prevalent and its link to cancer is clearly established providing a rationale for the implementation of dietary interventions as an adjuvant therapeutic strategy for malignancy.

Identification of the novel autoantigen candidate Rab GDP dissociation inhibitor alpha in isolated adrenocorticotropin deficiency.

Isolated adrenocorticotropin deficiency (IAD) is characterized by low or absent adrenocorticotropic hormone (ACTH) production. IAD is presumed to be caused in part by an autoimmune mechanism, and several lines of evidence have suggested the presence of anti-pituitary antibodies in IAD. However, the exact autoantigens remain unknown. The present study was designed to identify the autoantigen(s) in IAD using chromatography-tandem mass spectrometry (LC-MS/MS) analysis. Rat anterior pituitary lysate was subjected to SDS-PAGE, and immunoblotting was performed using the sera from two patients with IAD and from a healthy subject. The bands detected by the patient serum samples, but not by the healthy subject sample, were excised, in-gel digested using trypsin, and subjected to LC-MS/MS analysis. On immunoblots, a 51-kDa band in the insoluble pellet was detected by the sera from the IAD patients but not from the healthy subject. Mass spectrometric analysis revealed the 51-kDa band contained Rab guanine nucleotide dissociation inhibitor (GDI) alpha. Consistent with the mass spectrometric analysis, a recombinant full-length human Rab GDI alpha was recognized by the two IAD patient samples but not by the healthy subject sample using immunoblotting. In total, anti-Rab GDI alpha antibodies were detected in serum samples from three of five patients with IAD (60%) but were absent in 5 healthy subjects. In addition, Rab GDI alpha was expressed in the anterior pituitary. In conclusion, it appears that Rab GDI alpha is a candidate autoantigen involved in IAD, and that anti-Rab GDI alpha antibodies are present predominantly in patients with IAD.

The Historical Development of Immunoendocrine Concepts of Psychiatric Disorders and Their Therapy.

Relationships between the central nervous, immune and endocrine systems are a focus of psychiatric research, particularly in depression and schizophrenia. The field has long antecedents. Observed phenomena attributable to these relationships date back to the Neolithic era. Immunoendocrine theories in the broadest sense are recorded in antiquity. In the 19th century, Kraepelin and Wagner-Jauregg reported pioneering clinical observations in psychiatric patients. Von Basedow, Addison and Cushing described psychiatric symptoms in patients suffering from endocrine diseases. The 20th century opened with the identification of hormones, the first, adrenaline, chemically isolated independently by Aldrich und Takamine in 1901. Berson and Yalow developed the radioimmunoassay (RIA) technique in 1959 making it possible to measure levels of hormones and cytokines. These developments have enabled great strides in psychoimmunoendocrinology. Contemporary research is investigating diagnostic and therapeutic applications of these concepts, for example by identifying biomarkers within the endocrine and immune systems and by synthesizing and testing drugs that modulate these systems and show antidepressant or antipsychotic properties.

Pituitary autoimmunity in patients with diabetes mellitus and other endocrine disorders.

OBJECTIVE: Pituitary autoimmunity is often found in association with other endocrine autoimmune or non-autoimmune diseases. Aim of the study was to assess the prevalence of serum pituitary antibodies (PitAb) in patients with Type 1 diabetes mellitus (T1DM) or Type 2 diabetes mellitus (T2DM). RESEARCH DESIGN AND METHODS: In this casecontrol study 111 patients with T1DM, 110 patients with T2DM, and 214 healthy controls were enrolled in a tertiary referral center. Pituitary, thyroperoxidase, thyroglobulin, 21-hydroxylase, and parietal cell antibodies were assessed in all cases. Endocrine function was further assessed by basal hormone measurement and by dynamic tests, as well as a pituitary magnetic resonance imaging (MRI) was performed in those patients found positive for PitAb. RESULTS: PitAb prevalence was higher in T1DM (4 out of 111, 3.6%) than in T2DM (0 out of 110, p=0.045) and in healthy subjects (1 out of 214, 0.5% p=0.029). Prevalence of other autoimmune diseases was significantly higher in patients with T1DM (45 out of 111, 40.5%) when compared with patients with T2DM (18 out of 110 T2DM, 16.3%, p<0.001). Patients with T1DM and PitAb positivity were found with a pituitary lesion at MRI in 2 cases and pituitary dysfunction in one case. CONCLUSIONS: A significant association between pituitary autoimmunity and T1DM was found, in particular in subjects with one or more other endocrine autoimmune diseases.

Diagnostic value of the skin lesions in immune dysregulation, polyendocrinopathy, enteropathy, X-linked syndrome.

We report a child with immune dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) syndrome due to a de novo c.1190G>A (p.R397Q) mutation in exon 11 of the forkhead domain of the FOXP3 gene. He had chronic dermatitis with an eczematous and ichthyosiform appearance and had an allogeneic bone marrow transplantation. IPEX syndrome is a rare, often fatal recessive disease caused by mutations in the FOXP3 gene on the X chromosome (Xp11.23-q13.3).

Proteomics plus genomics approaches in primary immunodeficiency: the case of immune dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) syndrome.

Immune dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) is a rare syndrome due to a mutation in the forkhead box protein 3 gene (FOXP3) leading to an impaired regulatory T cell (T(reg) ) activity associated both with skewed T helper type 2 (Th2) response and autoreactive phenomena. The purpose of this study was to describe a combined proteomics and genomics approach to comprehensively evaluate clinical and immunological phenotypes of patients affected by IPEX. T cell receptor (TCR)-Vß repertoire and peripheral blood lymphocytes phenotype from three brothers affected by IPEX were studied by flow cytometry. Specific immunoglobulin (Ig)E were evaluated by means of an allergenic molecules microarray [immuno solid-phase allergen chip (ISAC)]. Total RNA was extracted and hybridized to Affymetrix oligonucleotide arrays to obtain quantitative gene-expression levels. No FOXP3 protein was detectable within CD127(-) CD25(high) CD4(+) T cells from peripheral blood. A T cell-naive phenotype (CD62L(+) CD45R0(-)) associated with a reduction of both CD26 and CD7 expression and a TCR-Vß 8 and 22 family expansions were found. B lymphocytes were mainly CD5(+) (B1) cells expressing a naive phenotype (tcl1(+) CD27(-)). The three IPEX patients had severe food allergy and specific IgE reactivity to cow's milk allergens, a hen's egg allergen and a wheat allergen. Gene expression profile analysis revealed a dysregulation associated mainly with Th1/Th2 pathways. The multiplexing evaluation reported in this study represents a comprehensive approach in the assessment of genetic conditions affecting the immune system such as the IPEX syndrome, paving the way for the development of diagnostic tools to improve the standard clinical and immunological profiling of the disease.