Autoimmunity, neuroinflammation, pathogen load: A decisive crosstalk in neuropsychiatric SLE

Neuropsychiatric manifestations in systemic lupus erythematosus and Sjogren's disease

INTRODUCTION

Autoimmune diseases often present in a systemic manner, affecting various organs and tissues. Involvement of the central and peripheral nervous system is not uncommon in these conditions and is associated with high morbidity and mortality. Therefore, early recognition of the neuropsychiatric manifestations associated with rheumatologic diseases is essential for the introduction of appropriate therapies with the objective of providing a better quality of life for individuals.

OBJECTIVE

To provide a literature review of the neuropsychiatric manifestations related to Systemic Lupus Erythematosus (SLE) and primary Sjögren's Disease (pSD), through the description of signs, symptoms, and immunological variables associated with these conditions.

METHODS

A literature review was conducted by searching for national and international articles available in the SciELO and PubMed databases related to the description of neurological and psychiatric manifestations in patients with the rheumatologic diseases of interest in this study.

RESULTS

The main NP manifestations presented in SLE and pSD are discussed, focusing on clinical presentation and etiology. Treatment option are, however, mainly based on expert opinion, since a few randomized controlled trials have been done.

CONCLUSIONS

There is a high prevalence of neuropsychiatric manifestations associated with SLE and pSD. The variety of physiopathology pathways may explain the variety of symptoms, however pathological findings are rare. Multicenter studies on attribution protocols and treatment are necessary to address the current gaps.

The association between systemic lupus erythematosus (SLE) and early psychiatric background

BACKGROUND

The etiology of Systemic Lupus Erythematosus (SLE) remains elusive. Research has established links between SLE and various mental health issues, including associations with psychiatric illness, unique symptomatology in SLE, a relationship between stress and disease exacerbation, and improvement in SLE patients after psychiatric and psychological treatment. However, the hypothesis that psychiatric conditions might precede SLE onset by long periods has not been empirically established. This study aims to address this gap.

METHODS

This matched cohort study conducted a retrospective analysis using the electronic database of Clalit Health Services (CHS), Israel's largest HMO, comparing 2786 individuals diagnosed with SLE with 8358 non-SLE matched controls.

RESULTS

Two logistic regression analysis tests revealed significant associations between SLE diagnosis and prior psychiatric conditions. the first (p < 0.001) showed a 120% higher likelihood of psychiatric history among those diagnosed at least 10 years later with SLE compared to controls, and the second (p = 0.008) showed a 61% greater likelihood of a psychiatric history among those diagnosed at least 15 years with SLE. Investigation into the association between specific psychiatric indices and the later development of SLE found significant correlations between an SLE diagnosis and four psychiatric indices 10 years prior: dispensing of antipsychotics, anxiolytics, hypnotics, and sedatives; dispensing of antidepressants, psychostimulants, ADHD agents, and nootropics; diagnosis of mood disorders; and phobic and anxiety disorders.

CONCLUSIONS

The increased probability of pre-existing mental health issues preceding SLE onset by extended durations suggests a potential etiological role in SLE development.

Constitutive knockout of interleukin-6 ameliorates memory deficits and entorhinal astrocytosis in the MRL/lpr mouse model of neuropsychiatric lupus

BACKGROUND

Neuropsychiatric lupus (NPSLE) describes the cognitive, memory, and affective emotional burdens faced by many lupus patients. While NPSLE's pathogenesis has not been fully elucidated, clinical imaging studies and cerebrospinal fluid (CSF) findings, namely elevated interleukin-6 (IL-6) levels, point to ongoing neuroinflammation in affected patients. Not only linked to systemic autoimmunity, IL-6 can also activate neurotoxic glial cells the brain. A prior pre-clinical study demonstrated that IL-6 can acutely induce a loss of sucrose preference; the present study sought to assess the necessity of chronic IL-6 exposure in the NPSLE-like disease of MRL/lpr lupus mice.

METHODS

We quantified 1308 proteins in individual serum or pooled CSF samples from MRL/lpr and control MRL/mpj mice using protein microarrays. Serum IL-6 levels were plotted against characteristic NPSLE neurobehavioral deficits. Next, IL-6 knockout MRL/lpr (IL-6 KO; n = 15) and IL-6 wildtype MRL/lpr mice (IL-6 WT; n = 15) underwent behavioral testing, focusing on murine correlates of learning and memory deficits, depression, and anxiety. Using qPCR, we quantified the expression of inflammatory genes in the cortex and hippocampus of MRL/lpr IL-6 KO and WT mice. Immunofluorescent staining was performed to quantify numbers of microglia (Iba1 +) and astrocytes (GFAP +) in multiple cortical regions, the hippocampus, and the amygdala.

RESULTS

MRL/lpr CSF analyses revealed increases in IL-17, MCP-1, TNF-α, and IL-6 (a priori p-value < 0.1). Serum levels of IL-6 correlated with learning and memory performance (R2 = 0.58; p = 0.03), but not motivated behavior, in MRL/lpr mice. Compared to MRL/lpr IL-6 WT, IL-6 KO mice exhibited improved novelty preference on object placement (45.4% vs 60.2%, p < 0.0001) and object recognition (48.9% vs 67.9%, p = 0.002) but equivalent performance in tests for anxiety-like disease and depression-like behavior. IL-6 KO mice displayed decreased cortical expression of aif1 (microglia; p = 0.049) and gfap (astrocytes; p = 0.044). Correspondingly, IL-6 KO mice exhibited decreased density of GFAP + cells compared to IL-6 WT in the entorhinal cortex (89 vs 148 cells/mm2, p = 0.037), an area vital to memory.

CONCLUSIONS

The inflammatory composition of MRL/lpr CSF resembles that of human NPSLE patients. Increased in the CNS, IL-6 is necessary to the development of learning and memory deficits in the MRL/lpr model of NPSLE. Furthermore, the stimulation of entorhinal astrocytosis appears to be a key mechanism by which IL-6 promotes these behavioral deficits.

Involvement of indoleamine 2, 3-dioxygenase (IDO) and brain-derived neurotrophic factor (BDNF) in the neuroprotective mechanisms of ferulic acid against depressive-like behaviour

OBJECTIVE

Ferulic acid (FA) is a common food ingredient that is abundantly present in various routinely consumed food and beverages. Like many cinnamic acid derivatives, FA produces wide-ranging effects in a dose-dependent manner and various studies link FA consumption with reduced risk of depressive disorders. The aim of this study was to exploit the neuroprotective mechanisms of FA including indoleamine 2,3-dioxygenase (IDO), brain-derived neurotrophic factor (BDNF), and other pro-inflammatory cytokines by employing lipopolysaccharide (LPS)-induced depressive-like behaviour model.

METHODS

C57BL/6J male mice were divided into 4 groups consisting of saline (SAL), LPS, FA and Imipramine (IMI). Animals were pretreated orally with FA (10 mg/kg) and IMI (10 mg/kg) for 21 days once daily and all groups except SAL were challenged with LPS (0.83 mg/kg) intraperitoneally on day 21.

RESULTS

LPS administration produced a biphasic change in the behaviour of the animals where the animals lost a significant weight and express high immobility time at 24 h. Proinflammatory cytokines including, TNF-α, IL-6, IL-1β, and IFN-γ were significantly increased along with increased lipid peroxidation and reduced BDNF. Furthermore, the increased kynurenine to tryptophan ratio was indicative of elevated IDO activity.

CONCLUSION

The results of this study emphasise that low dose of FA is effective in attenuating depressive-like behaviour by modulating IDO, BDNF and reducing neuroinflammation.

Posterior reversible encephalopathy syndrome and autoimmunity

Posterior reversible encephalopathy syndrome (PRES) is a clinical syndrome characterized by acute or subacute onset of neurological symptoms (e.g., headache, seizure, confusion, vomiting, and diminished eyesight) and impaired endothelial barrier function of the cerebral circulation that leads to bilateral subcortical vasogenic edema, while exhibiting a "reversible" feature in most cases. Clinically, various predisposing or precipitating conditions have been identified, such as hypertension, autoimmune diseases, renal dysfunction/failure, preeclampsia/eclampsia, post-transplantation conditions, and certain therapeutic agents. Among several putative mechanisms, the immune activation hypothesis prevails, as up to 50% of patients with PRES harbor abnormalities related to autoimmunity, such as concurrent systemic lupus erythematosus. In this Review, we summarize the clinical and laboratory evidence that places PRES in the context of autoimmunity.

The correlation between proteoglycan 2 and neuropsychiatric systemic lupus erythematosus

The proposed pathogenesis of neuropsychiatric systemic lupus erythematosus (NPSLE) mainly includes ischemia and neuroinflammation mechanisms. Protein encoded by Proteoglycan 2 (PRG2) mRNA is involved in the immune process related to eosinophils, also being found in the placenta and peripheral blood of pregnant women. We evaluated the correlation between PRG2 and NPSLE for the first time and found that PRG2 protein is overexpressed in the serum of patients with NPSLE and correlated with the SLE disease activity index (SLEDAI) subset scores of psychosis. Moreover, we investigated the correlation between hippocampal PRG2 level and hippocampally dependent learning and memory ability in MRL/lpr mice, and discovered that the number of PRG2⁺GFAP⁺ astrocytes in the cortex and hypothalamus and the number of PRG2⁺IBA-1⁺ microglia in the hippocampus and cortex significantly increased in the MRL/lpr mice. These data provided a reference for the follow-up exploration of the role of PRG2 in SLE or other diseases.

Nuclear receptors modulate inflammasomes in the pathophysiology and treatment of major depressive disorder

Major depressive disorder (MDD) is highly prevalent and is a significant cause of mortality and morbidity worldwide. Currently, conventional pharmacological treatments for MDD produce temporary remission in < 50% of patients; therefore, there is an urgent need for a wider spectrum of novel antidepressants to target newly discovered underlying disease mechanisms. Accumulated evidence has shown that immune inflammation, particularly inflammasome activity, plays an important role in the pathophysiology of MDD. In this review, we summarize the evidence on nuclear receptors (NRs), such as glucocorticoid receptor, mineralocorticoid receptor, estrogen receptor, aryl hydrocarbon receptor, and peroxisome proliferator-activated receptor, in modulating the inflammasome activity and depression-associated behaviors. This review provides evidence from an endocrine perspective to understand the role of activated NRs in the pathophysiology of MDD, and to provide insight for the discovery of antidepressants with novel mechanisms for this devastating disorder.

Beyond Neuropsychiatric Manifestations of Systemic Lupus Erythematosus: Focus on Post-traumatic Stress Disorder and Alexithymia

PURPOSE OF REVIEW

To deepen the comprehension of the role of specific psychological conditions in the pathogenesis and in the treatment of systemic lupus erythematosus (SLE). Specifically, the present comprehensive review aims at examining the association between SLE, alexithymia (AT)-a personality construct referring to the inability to identify, describe, and express sensations, emotions, and physical state-and post-traumatic stress disorder (PTSD), to infer potential biological relationships between these psychopathological issues and disease course, and to draw up a research agenda on gray areas of these topics.

RECENT FINDINGS

Whereas several studies document the presence of neuropsychiatric symptoms in patients with SLE, psychological distress, alexithymia, and post-traumatic manifestations are usually neglected by healthcare professionals and poorly investigated in research contexts. However, the interplay of these aspects, which affect physiologic stress coping mechanisms, potentially plays an important role in SLE pathogenesis. In particular, research documents that cytokine repertoire pattern alteration and hypothalamic-pituitary-adrenal axis impairment leading to inflammation and pain represent the main links between emotional health and immunity. AT and PTSD seem to be common in patients with SLE and account for multiple aspects of SLE-related morbidity. Furthermore, abnormal processing of stressful stimuli as hallmarks of PTSD and AT might promote neuroendocrine dysfunction and dysregulated immunity, thus contributing to the pathogenesis of SLE. A comprehensive, multidisciplinary clinical approach, based on a cooperation between immunologists, rheumatologists, neurologists, and mental health professionals, is crucial to promote patients' global health.

Brain white matter extracellular free-water increases are related to reduced neurocognitive function in systemic lupus erythematosus

OBJECTIVES

Brain white matter (WM) microstructural changes evaluated by diffusion MRI were well documented in patients with systemic lupus erythematosus (SLE). Yet, conventional diffusion tensor imaging technique fails to differentiate WM changes that originate from tissue alterations from those due to increased extracellular free water (FW) related to neuroinflammation, microvascular disruption, atrophy, or other extracellular processes. Here, we sought to delineate changes in WM tissue microstructure and extracellular FW volume and examine their relationships with neurocognitive function in SLE patients.

METHODS

Twenty SLE patients (16 females, aged 36.0±10.6) without clinically-overt neuropsychiatric manifestation and 61 healthy controls (HC) (29 females, aged 29.2±9.4) underwent diffusion MRI and computerized neuropsychological assessments cross-sectionally. The FW imaging method was applied to compare microstructural tissue changes and extracellular FW volume of the brain WM between SLE patients and HC. Association between extracellular FW changes and neurocognitive performance was studied.

RESULTS

SLE patients had higher WM extracellular FW compared to HC (family-wise-error-corrected p < 0.05) while no group difference was found in FW-corrected tissue compartment and structural connectivity metrics. Extracellular FW increases in SLE patients were associated with poorer neurocognitive performance that probed sustained attention (p = 0.022) and higher cumulative glucocorticoid dose (p = 0.0041). Such findings remained robust after controlling for age, gender, IQ, and total WM volume.

CONCLUSIONS

The association between WM extracellular FW increases and reduced neurocognitive performance suggest possible microvascular degradation and/or neuroinflammation in SLE patients with clinically-inactive disease. The mechanistic impact of cumulative glucocorticoids on WM FW deserves further evaluation.

Relevant Characteristics Analysis Using Natural Language Processing and Machine Learning Based on Phenotypes and T-Cell Subsets in Systemic Lupus Erythematosus Patients With Anxiety

Anxiety is frequently observed in patients with systemic lupus erythematosus (SLE) and the immune system could act as a trigger for anxiety. To recognize abnormal T-cell and B-cell subsets for SLE patients with anxiety, in this study, patient disease phenotypes data from electronic lupus symptom records were extracted by using natural language processing. The Hospital Anxiety and Depression Scale (HADS) was used to distinguish patients, and 107 patients were selected to meet research requirements. Then, peripheral blood was collected from two patient groups for multicolor flow cytometry experiments. The characteristics of 75 T-cell and 15 B-cell subsets were investigated between SLE patients with- (n = 23) and without-anxiety (n = 84) groups by four machine learning methods. The findings showed 13 T-cell subsets were significantly different between the two groups. Furthermore, BMI, fatigue, depression, unstable emotions, CD27⁺CD28⁺ Th/Treg, CD27^-CD28^- Th/Treg, CD45RA^-CD27^- Th, and CD45RA⁺HLADR⁺ Th cells may be important characteristics between SLE patients with- and without-anxiety groups. The findings not only point out the difference of T-cell subsets in SLE patients with or without anxiety, but also imply that T cells might play the important role in patients with anxiety disorder.

Management of inflammatory neurologic and psychiatric manifestations of systemic lupus erythematosus: A systematic review

BACKGROUND

The neurological and psychiatric manifestations of systemic lupus erythematosus (NPSLE) are a heterogeneous group of conditions with variable clinical presentation and significant morbidity and mortality.

OBJECTIVES

Our aim was to comprehensively assess and present the evidence for treatments used in the management of inflammatory NPSLE.

METHODS

Medline, Embase, CINHAL and Cochrane CENTRAL were searched from 1990 to end of March 2019 using key words that related to NPSLE and treatment. Included studies comprised clinical trials, observational studies or case series with ≥5 patients and sufficient data related to treatment and outcome in NPSLE patients.

RESULTS

There were 7222 studies identified in the search, of which 90 were included in the review. There was a notable paucity of clinical trials, with only two randomised controlled trials and one pilot study. Treatment categories included corticosteroids (14 studies), cyclophosphamide (18 studies), synthetic DMARDs (7 studies), biologic therapies (14 studies), therapeutic plasma exchange (6 studies), intravenous immunoglobulin (2 studies), autologous stem cell transplant (3 studies), other therapies (8 studies), combination therapies (6 studies), studies with grouped outcome data (5 studies) and observational studies with therapy-specific associations (7 studies). Corticosteroids are accepted as first line treatment in NPSLE and there is low-moderate evidence supporting their benefit. Moderate evidence, based on consistent data in numerous studies and some trial data, supports the use of cyclophosphamide in the treatment of NPSLE. Limited data support some synthetic DMARDs such as mycophenolate, azathioprine and intrathecal methotrexate. In refractory disease, low-moderate evidence supports rituximab therapy and limited evidence supports benefit following autologous stem cell transplant. Regarding adjuvant treatments, limited evidence favours addition of plasma exchange, intravenous immunoglobulin and hydroxychloroquine. There exists very limited data for other therapies.

CONCLUSION

There are multiple therapeutic options for the management of inflammatory NPSLE including systemic, biologic and interventional therapies; however, currently there is a paucity of high-quality trial data to guide firm recommendations. In order to better understand the optimal treatment of NPSLE and its different subtypes, further well-designed clinical trials are needed.

Mathematical processing is affected by daily but not cumulative glucocorticoid dose in patients with systemic lupus erythematosus

OBJECTIVES

The impact of glucocorticoids on neurocognitive performance in patients with SLE is not fully addressed. We aimed to study the effect of daily and cumulative glucocorticoid dose on neurocognitive performance in SLE patients.

METHODS

Consecutive SLE patients and gender- and age-matched healthy controls (HCs) underwent the computer-based Automated Neuropsychological Assessment Matric (ANAM), which evaluates eight neurocognitive domains including learning, recall, visual perception, mental rotation, short-term memory, attention, sustained attention and working memory. The total and individual-domain throughput scores (TPSs) and the presence of cognitive dysfunction (total TPS <1.5 s.d. below the mean TPS of HCs) were compared between SLE patients and HCs. Within the SLE group, univariate and independent associations between prednisolone dose (daily and cumulative) and individual-domain TPS were studied by univariate and multivariable linear regression, respectively.

RESULTS

A total of 96 SLE patients and 96 HCs were studied. SLE patients scored significantly worse across all the neurocognitive domains and had a significantly lower mean total TPS (P < 0.001) and a higher prevalence of cognitive dysfunction compared with HCs (25.0 vs 7.3%, P = 0.001). In SLE patients, daily prednisolone dose was significantly and negatively correlated with mathematical-processing TPS, which probes working memory (P = 0.018). No significant correlation between cumulative prednisolone dose and any of the individual-domain TPSs was found. In multivariable regression, higher daily prednisolone dose and doses >9 mg daily remained independently associated with lower mathematical-processing TPSs (P = 0.031).

CONCLUSION

Daily prednisolone dose ≥9 mg, but not cumulative glucocorticoid dose, had an independent negative impact on mathematical processing in SLE patients.

Update on the pathogenesis of central nervous system lupus

PROPOSE OF REVIEW

Neuropsychiatric systemic lupus erythematosus (NPSLE) is an emerging frontier in lupus care encompassing a wide spectrum of clinical manifestations. Its pathogenesis remains poorly understood because of the complexity of pathophysiologic mechanisms involved and limited access to tissue. We highlight recent advances in the pathophysiology of neuropsychiatric lupus.

RECENT FINDINGS

Disruption of blood-brain barrier (BBB) facilitating entrance of neurotoxic antibodies into the central nervous system (CNS), neuroinflammation and cerebral ischemia are the key mechanisms. Disruption of the BBB may occur not only at the traditional BBB, but also at the blood-cerebrospinal fluid barrier. Certain autoantibodies, such as anti-N-methyl-D-aspartate receptors, antiribosomal P and antiphospholipid antibodies may cause injury in subsets of patients with diffuse neuropsychiatric disease. Activation of microglia via autoantibodies, interferon-a or other immune reactants, may amplify the inflammatory response and promote neuronal damage. New inflammatory pathways, such as TWEAK/Fn14, Bruton's tyrosine kinase, Nogo-a and ACE may represent additional potential targets of therapy. Novel neuroimaging techniques suggest alterations in brain perfusion and metabolism, increased concentration of neurometabolites, indicative of glial activation, vasculopathy and neuronal impairment.

SUMMARY

NPSLE encompasses a diverse phenotype with distinct pathogenic mechanisms, which could be targeted by novel therapies or repositioning of existing drugs.

Neurodegeneration in systemic lupus erythematosus: layer by layer retinal study using optical coherence tomography

Background

Systemic lupus erythematosus (SLE) is a chronic, autoimmune and multisystemic disease. Recent studies with functional and structural magnetic resonance imaging and cognitive tests report an unexpectedly high frequency of central nervous system involvement, even in patients with asymptomatic SLE. The purpose of this study was to identify early signs of retinal neurodegeneration by comparing the thickness of the peripapillary retinal nerve fiber layer (pRNFL) and all macular layers between patients with SLE without ophthalmologic manifestations and healthy controls. The effect of disease duration and systemic comorbidities was also studied.

Methods

Cross-sectional study, in which all participants underwent a complete ophthalmologic evaluation including retinal segmentation analysis with spectral domain-optical coherence tomography. Patients with SLE also received a detailed autoimmune disease specialist evaluation to assess the disease activity state and systemic involvement. For pRNFL thickness, the global and six peripapillary sectors were determined. Each macular layer thickness was determined in the nine Early Treatment Diabetic Retinopathy Study (ETDRS) subfields. A multiple linear regression analysis was performed to control for the effect of potential demographic, ophthalmic and systemic confounders. A second multivariable analysis, including patients with SLE only, was performed to assess the effect of disease-specific variables on the outcome measures.

Results

Sixty-eight eyes of 68 patients with SLE and 50 eyes of 50 healthy controls were considered. The pRNFL was significantly thinner in the SLE group globally (p = 0.026) and in the temporal superior (p = 0.007) and temporal (p = 0.037) sectors. In patients with SLE, chronic medication for hypercholesterolemia, hypertension and anticoagulants were associated with a significant thinning of the pRNFL. Patients with SLE presented significant thinning in the photoreceptor layer in five ETDRS areas (p < 0.05). Shorter disease duration was associated with greater photoreceptor thinning in all ETDRS subfields. Neuropsychiatric SLE, higher disease activity and cardiovascular risk factors were associated with a thinner photoreceptor layer. No differences were observed in overall retinal thickness or the remaining macular layers.

Conclusion

Patients with SLE present early signs of retinal neurodegeneration, as evidenced by a reduction in the photoreceptor layer and pRNFL. These signs are more pronounced in patients with higher cardiovascular risk burden or neuropsychiatric involvement.

From Systemic Inflammation to Neuroinflammation: The Case of Neurolupus

It took decades to arrive at the general consensus dismissing the notion that the immune system is independent of the central nervous system. In the case of uncontrolled systemic inflammation, the relationship between the two systems is thrown off balance and results in cognitive and emotional impairment. It is specifically true for autoimmune pathologies where the central nervous system is affected as a result of systemic inflammation. Along with boosting circulating cytokine levels, systemic inflammation can lead to aberrant brain-resident immune cell activation, leakage of the blood⁻brain barrier, and the production of circulating antibodies that cross-react with brain antigens. One of the most disabling autoimmune pathologies known to have an effect on the central nervous system secondary to the systemic disease is systemic lupus erythematosus. Its neuropsychiatric expression has been extensively studied in lupus-like disease murine models that develop an autoimmunity-associated behavioral syndrome. These models are very useful for studying how the peripheral immune system and systemic inflammation can influence brain functions. In this review, we summarize the experimental data reported on murine models developing autoimmune diseases and systemic inflammation, and we explore the underlying mechanisms explaining how systemic inflammation can result in behavioral deficits, with a special focus on in vivo neuroimaging techniques.

Hashimoto's thyroiditis induces neuroinflammation and emotional alterations in euthyroid mice

Background

Although studies have reported an increased risk for mood disorders in Hashimoto’s thyroiditis (HT) patients even in the euthyroid state, the mechanisms involved remain unclear. Neuroinflammation may play a key role in the etiology of mood disorders in humans and behavioral disturbances in rodents. Therefore, this study established a euthyroid HT model in mice and investigated whether HT itself was capable of triggering neuroinflammation accompanied by emotional alterations.

Methods

Experimental HT was induced by immunizing NOD mice with thyroglobulin and adjuvant twice. Four weeks after the last challenge, mice were tested for anxiety-like behavior in the open field and elevated plus maze tests and depression-like behavior in the forced swimming and tail suspension tests. Then, animals were sacrificed for thyroid-related parameter measure as well as detection of cellular and molecular events associated with neuroinflammation. The changes in components of central serotonin signaling were also investigated.

Results

HT mice showed intrathyroidal monocyte infiltration and rising serum thyroid autoantibody levels accompanied by normal thyroid function, which defines euthyroid HT in humans. These mice displayed more anxiety- and depressive-like behaviors than controls. HT mice further showed microglia and astrocyte activation in the frontal cortex detected by immunohistochemistry, real-time RT-PCR, and transmission electron microscopy (TEM). These observations were also accompanied by enhanced gene expression of proinflammatory cytokines IL-1β and TNF-α in the frontal cortex. Despite this inflammatory response, no signs of neuronal apoptosis were visible by the TUNEL staining and TEM in the frontal cortex of HT mice. Additionally, IDO1 and SERT, key serotonin-system-related genes activated by proinflammatory cytokines, were upregulated in HT mice, accompanied by reduced frontal cortex serotonin levels.

Conclusions

Our results are the first to suggest that HT induces neuroinflammation and alters related serotonin signaling in the euthyroid state, which may underlie the deleterious effects of HT itself on emotional function.

The Mitochondrion-lysosome Axis in Adaptive and Innate Immunity: Effect of Lupus Regulator Peptide P140 on Mitochondria Autophagy and NETosis

Mitochondria deserve special attention as sensors of cellular energy homeostasis and metabolic state. Moreover, mitochondria integrate intra- and extra-cellular signals to determine appropriate cellular responses that range from proliferation to cell death. In autoimmunity, as in other inflammatory chronic disorders, the metabolism of immune cells may be extensively remodeled, perturbing sensitive tolerogenic mechanisms. Here, we examine the distribution and effects of the therapeutic 21-mer peptide called P140, which shows remarkable efficacy in modulating immune responses in inflammatory settings. We measured P140 and control peptide effects on isolated mitochondria, the distribution of peptides in live cells, and their influence on the levels of key autophagy regulators. Our data indicate that while P140 targets macro- and chaperone-mediated autophagy processes, it has little effect, if any, on mitochondrial autophagy. Remarkably, however, it suppresses NET release from neutrophils exposed to immobilized NET-anti-DNA IgG complexes. Together, our results suggest that in the mitochondrion-lysosome axis, a likely driver of NETosis and inflammation, the P140 peptide does not operate by affecting mitochondria directly.

Safety issues and recommendations for successful pregnancy outcome in systemic lupus erythematosus

Systemic lupus erythematosus (SLE) primarily affects women of childbearing age. One of the major changes in SLE focuses on the timing of a successful pregnancy. In the past, pregnancy was strongly discouraged in SLE, especially in the presence of risk factors such as nephritis, use of immunosuppressive therapies, or positivity of specific autoantibodies such as anti-phospholipids and anti-Ro/SSA, La/SSBA. Thanks to our better knowledge on the disease and management, pregnancy success rates in SLE patients have significantly improved care by the a multidisciplinary team which fosters a successful pregnancy with minimal complications for the mother and fetus when the disease is inactive or in remission. This approach is based on a counseling phase before pregnancy, to assess SLE activity phase, specific medications, risk factors, and continues through pregnancy and lactation with significantly improved pregnancy outcomes. Further, we can now better define the risk of disease flares during pregnancy based on a better understanding of the changes in maternal immunity and its relationship with SLE-associated autoimmunity and chronic inflammation. There is wide consensus that women with SLE can have successful pregnancies as long as conception is planned in a phase of inactive disease, and when the patient is closely managed by a rheumatologist, high-risk OB/GYN, neonatologist, and other medical specialists as indicated. Preconception counseling is essential to assess the risk of both fetal and maternal complications as well as identify life-threatening contraindications. Particular attention should be used in those SLE cases that have nephritis, APS or positivity for aPL, pulmonary hypertension, and positive anti-Ro/SSA or anti-La/SSB antibodies. In conclusion, the use of specific guidelines on the management of SLE before and during pregnancy and lactation, and a better understanding of the use of immunosuppressive therapies have significantly increased pregnancy success.

Autoimmunity in 2016

The number of peer-reviewed articles published during the 2016 solar year and retrieved using the "autoimmunity" key word remained stable while gaining a minimal edge among the immunology articles. Nonetheless, the quality of the publications has been rising significantly and, importantly, acquisitions have become available through scientific journals dedicated to immunology or autoimmunity. Major discoveries have been made in the fields of systemic lupus erythematosus, rheumatoid arthritis, autoimmunity of the central nervous system, vasculitis, and seronegative spondyloarthrithritides. Selected examples include the role of IL17-related genes and long noncoding RNAs in systemic lupus erythematosus or the effects of anti-pentraxin 3 (PTX3) in the treatment of this paradigmatic autoimmune condition. In the case of rheumatoid arthritis, there have been reports of the role of induced regulatory T cells (iTregs) or fibrocytes and T cell interactions with exciting implications. The large number of studies dealing with neuroimmunology pointed to Th17 cells, CD56(bright) NK cells, and low-level TLR2 ligands as involved in multiple sclerosis, along with a high salt intake or the micriobiome-derived Lipid 654. Lastly, we focused on the rare vasculitides to which numerous studies were devoted and suggested that unsuspected cell populations, including monocytes, mucosal-associated invariant T cells, and innate lymphoid cells, may be crucial to ANCA-associated manifestations. This brief and arbitrary discussion of the findings published in 2016 is representative of a promising background for developments that will enormously impact the work of laboratory scientists and physicians at an exponential rate.

Mold and Human Health: a Reality Check

There are possibly millions of mold species on earth. The vast majority of these mold spores live in harmony with humans, rarely causing disease. The rare species that does cause disease does so by triggering allergies or asthma, or may be involved in hypersensitivity diseases such as allergic bronchopulmonary aspergillosis or allergic fungal sinusitis. Other hypersensitivity diseases include those related to occupational or domiciliary exposures to certain mold species, as in the case of Pigeon Breeder's disease, Farmer's lung, or humidifier fever. The final proven category of fungal diseases is through infection, as in the case of onchomycosis or coccidiomycosis. These diseases can be treated using anti-fungal agents. Molds and fungi can also be particularly important in infections that occur in immunocompromised patients. Systemic candidiasis does not occur unless the individual is immunodeficient. Previous reports of "toxic mold syndrome" or "toxic black mold" have been shown to be no more than media hype and mass hysteria, partly stemming from the misinterpreted concept of the "sick building syndrome." There is no scientific evidence that exposure to visible black mold in apartments and buildings can lead to the vague and subjective symptoms of memory loss, inability to focus, fatigue, and headaches that were reported by people who erroneously believed that they were suffering from "mycotoxicosis." Similarly, a causal relationship between cases of infant pulmonary hemorrhage and exposure to "black mold" has never been proven. Finally, there is no evidence of a link between autoimmune disease and mold exposure.

Development of autoantibodies precedes clinical manifestations of autoimmune diseases: A comprehensive review

The etiology of autoimmune diseases is due to a combination of genetic predisposition and environmental factors that alter the expression of immune regulatory genes through various mechanisms including epigenetics. Both humoral and cellular elements of the adaptive immune system play a role in the pathogenesis of autoimmune diseases and the presence of autoantibodies have been detected in most but not all autoimmune diseases before the appearance of clinical symptoms. In some cases, the presence or levels of these autoantibodies portends not only the risk of developing a corresponding autoimmune disease, but occasionally the severity as well. This observation is intriguing because it suggests that we can, to some degree, predict who may or may not develop autoimmune diseases. However, the role of autoantibodies in the pathogenesis of autoimmune diseases, whether they actually affect disease progression or are merely an epiphenomenon is still not completely clear in many autoimmune diseases. Because of these gaps in our knowledge, the ability to accurately predict a future autoimmune disease can only be considered a relative risk factor. Importantly, it raises the critical question of defining other events that may drive a patient from a preclinical to a clinical phase of disease.

Reduced volumes of the CA1 and CA4-dentate gyrus hippocampal subfields in systemic lupus erythematosus

Introduction There is evidence for hippocampal dysfunctions in systemic lupus erythematosus (SLE), which may contribute to neuropsychiatric impairments. However, fine structural alterations of the hippocampus have not been investigated in SLE. Methods We measured the volume of hippocampal subfields in 18 SLE patients and 20 healthy control individuals matched for age, gender, and education. The MRI protocol included structural T1 volumes (Philips Achieva 3T scanner, magnetization-prepared rapid acquisition gradient echo (MPRAGE)). For image processing, we used the neuGRID platform and the longitudinal pipeline of FreeSurfer v6.0 with the "hipposubfields" flag. Results Patients with SLE showed reduced volumes of CA1 (Cornu Ammonis 1) and CA4-dentate gyrus subfields relative to the control individuals. Smaller CA1 volumes were associated with worse performance on the Addenbrooke's Cognitive Examination. Conclusions These preliminary results indicate a prominent vulnerability and functional relevance of the CA1 hippocampal subfield in SLE.

Demyelinating syndrome in SLE encompasses different subtypes: Do we need new classification criteria? Pooled results from systematic literature review and monocentric cohort analysis

OBJECTIVE

To describe features of demyelinating syndrome (DS) in systemic lupus erythematosus (SLE).

METHODS

A systematic review using a combination of Mesh terms in PubMed and a retrospective analysis of 343 adult patients with SLE were carried out to identify patients with DS. Retrieved cases were classified as affected with DS according to 1999 ACR nomenclature and attributed to SLE by applying the 2015 algorithm. DS defined according to the clinical but not temporal 1999 ACR criteria was classified as clinically isolated syndrome (CIS).

RESULTS

Estimated prevalence of DS (including CIS) in the SLE cohort was 1.3% and incidence rate was 1.5 cases per 1000 patient-years. Overall, 100 cases from literature review and 4 from SLE cohort were identified and are presented as a whole: 49 (47.1%) were classified as neuromyelitis optica spectrum disorders (NMOSD), 29 (27.9%) as CIS, 14 (13.5%) as NMO, 7 (6.7%) as DS prominently involving the brainstem and 5 (4.8%) as DS prominently involving the brain. DS was the SLE onset manifestation in 41 (39.4%) patients. Longitudinally extensive transverse myelitis was the most frequent manifestations being present in 73 (70.2%) patients (37 NMOSD, 21 CIS, 14 NMO, 1 DSB). Methylprednisolone (79.8%) and cyclophosphamide (55.8%) pulses, but also plasma-exchange (16.3%) and rituximab (7.6%) in relapsing-refractory cases, were mostly prescribed. Complete recovery rate ranged between 62% in CIS to 7% in NMO.

CONCLUSION

DS in SLE is rare (1%) and encompasses different subtypes including CIS. Timely diagnosis and early treatment are recommended to minimize complications.