Pleiotropic Effects of Glucocorticoids on the Immune System in Circadian Rhythm and Stress

Ecological countermeasures to prevent pathogen spillover and subsequent pandemics

Substantial global attention is focused on how to reduce the risk of future pandemics. Reducing this risk requires investment in prevention, preparedness, and response. Although preparedness and response have received significant focus, prevention, especially the prevention of zoonotic spillover, remains largely absent from global conversations. This oversight is due in part to the lack of a clear definition of prevention and lack of guidance on how to achieve it. To address this gap, we elucidate the mechanisms linking environmental change and zoonotic spillover using spillover of viruses from bats as a case study. We identify ecological interventions that can disrupt these spillover mechanisms and propose policy frameworks for their implementation. Recognizing that pandemics originate in ecological systems, we advocate for integrating ecological approaches alongside biomedical approaches in a comprehensive and balanced pandemic prevention strategy.

Advances in understanding bat infection dynamics across biological scales

Over the past two decades, research on bat-associated microbes such as viruses, bacteria and fungi has dramatically increased. Here, we synthesize themes from a conference symposium focused on advances in the research of bats and their microbes, including physiological, immunological, ecological and epidemiological research that has improved our understanding of bat infection dynamics at multiple biological scales. We first present metrics for measuring individual bat responses to infection and challenges associated with using these metrics. We next discuss infection dynamics within bat populations of the same species, before introducing complexities that arise in multi-species communities of bats, humans and/or livestock. Finally, we outline critical gaps and opportunities for future interdisciplinary work on topics involving bats and their microbes.

Stress systems exacerbate the inflammatory response after corneal abrasion in sleep-deprived mice via the IL-17 signaling pathway

Sleep deprivation (SD) has a wide range of adverse health effects. However, the mechanisms by which SD influences corneal pathophysiology and its post-wound healing remain unclear. This study aimed to examine the basic physiological characteristics of the cornea in mice subjected to SD and determine the pathophysiological response to injury after corneal abrasion. Using a multi-platform water environment method as an SD model, we found that SD leads to disturbances of corneal proliferative, sensory, and immune homeostasis as well as excessive inflammatory response and delayed repair after corneal abrasion by inducing hyperactivation of the sympathetic nervous system and hypothalamic-pituitary-adrenal axis. Pathophysiological changes in the cornea mainly occurred through the activation of the IL-17 signaling pathway. Blocking both adrenergic and glucocorticoid synthesis and locally neutralizing IL-17A significantly improved corneal homeostasis and the excessive inflammatory response and delay in wound repair following corneal injury in SD-treated mice. These results indicate that optimal sleep quality is essential for the physiological homeostasis of the cornea and its well-established repair process after injury. Additionally, these observations provide potential therapeutic targets to ameliorate SD-induced delays in corneal wound repair by inhibiting or blocking the activation of the stress system and its associated IL-17 signaling pathway.

The effectiveness of glucocorticoid treatment in post-COVID-19 pulmonary involvement

RATIONALE

Persistent respiratory symptoms following Coronavirus Disease 2019 (COVID-19) are associated with residual radiological changes in lung parenchyma, with a risk of development into lung fibrosis, and with impaired pulmonary function. Previous studies hinted at the possible efficacy of corticosteroids (CS) in facilitating the resolution of post-COVID residual changes in the lungs, but the available data is limited.

AIM

To evaluate the effects of CS treatment in post-COVID respiratory syndrome patients.

PATIENTS AND METHODS

Post-COVID patients were recruited into a prospective single-center observational study and scheduled for an initial (V1) and follow-up visit (V2) at the Department of Respiratory Medicine and Tuberculosis, University Hospital Olomouc, comprising of pulmonary function testing, chest x-ray, and complex clinical examination. The decision to administer CS or maintain watchful waiting (WW) was in line with Czech national guidelines.

RESULTS

The study involved 2729 COVID-19 survivors (45.7% male; mean age: 54.6). From 2026 patients with complete V1 data, 131 patients were indicated for CS therapy. These patients showed significantly worse radiological and functional impairment at V1. Mean initial dose was 27.6 mg (SD ± 10,64), and the mean duration of CS therapy was 13.3 weeks (SD ± 10,06). Following therapy, significantly better improvement of static lung volumes and transfer factor for carbon monoxide (DLCO), and significantly better rates of good or complete radiological and subjective improvement were observed in the CS group compared to controls with available follow-up data (n = 894).

CONCLUSION

Better improvement of pulmonary function, radiological findings and subjective symptoms were observed in patients CS compared to watchful waiting. Our findings suggest that glucocorticoid therapy could benefit selected patients with persistent dyspnea, significant radiological changes, and decreased DLCO.

Immune-neuroendocrine patterning and response to stress. A latent profile analysis in the English longitudinal study of ageing

Psychosocial stress exposure can disturb communication signals between the immune, nervous, and endocrine systems that are intended to maintain homeostasis. This dysregulation can provoke a negative feedback loop between each system that has high pathological risk. Here, we explore patterns of immune-neuroendocrine activity and the role of stress. Using data from the English Longitudinal Study of Ageing (ELSA), we first identified the latent structure of immune-neuroendocrine activity (indexed by high sensitivity C-reactive protein [CRP], fibrinogen [Fb], hair cortisol [cortisol], and insulin growth-factor-1 [IGF-1]), within a population-based cohort using latent profile analysis (LPA). Then, we determined whether life stress was associated with membership of different immune-neuroendocrine profiles. We followed 4,934 male and female participants, with a median age of 65 years, over a four-year period (2008-2012). A three-class LPA solution offered the most parsimonious fit to the underlying immune-neuroendocrine structure in the data, with 36 %, 40 %, and 24 % of the population belonging to profiles 1 (low-risk), 2 (moderate-risk), and 3 (high-risk), respectively. After adjustment for genetic predisposition, sociodemographics, lifestyle, and health, higher exposure to stress was associated with a 61 % greater risk of belonging to the high-risk profile (RRR: 1.61; 95 %CI = 1.23-2.12, p = 0.001), but not the moderate-risk profile (RRR = 1.10, 95 %CI = 0.89-1.35, p = 0.401), as compared with the low-risk profile four years later. Our findings extend existing knowledge on psychoneuroimmunological processes, by revealing how inflammation and neuroendocrine activity cluster in a representative sample of older adults, and how stress exposure was associated with immune-neuroendocrine responses over time.

Circadian control of ConA-induced acute liver injury and inflammatory response via Bmal1 regulation of Junb

Background & Aims

Circadian rhythms play significant roles in immune responses, and many inflammatory processes in liver diseases are associated with malfunctioning molecular clocks. However, the significance of the circadian clock in autoimmune hepatitis (AIH), which is characterised by immune-mediated hepatocyte destruction and extensive inflammatory cytokine production, remains unclear.

Methods

We tested the difference in susceptibility to the immune-mediated liver injury induced by concanavalin A (ConA) at various time points throughout a day in mice and analysed the effects of global, hepatocyte, or myeloid cell deletion of the core clock gene, Bmal1 (basic helix-loop-helix ARNT-like 1), on liver injury and inflammatory responses. Multiple molecular biology techniques and mice with macrophage-specific knockdown of Junb, a Bmal1 target gene, were used to investigate the involvement of Junb in the circadian control of ConA-induced hepatitis.

Results

The susceptibility to ConA-induced liver injury is highly dependent on the timing of ConA injection. The treatment at Zeitgeber time 0 (lights on) triggers the highest mortality as well as the severest liver injury and inflammatory responses. Further study revealed that this timing effect was driven by macrophage, but not hepatocyte, Bmal1. Mechanistically, Bmal1 controls the diurnal variation of ConA-induced hepatitis by directly regulating the circadian transcription of Junb and promoting M1 macrophage activation. Inhibition of Junb in macrophages blunts the administration time-dependent effect of ConA and attenuates liver injury. Moreover, we demonstrated that Junb promotes macrophage inflammation by regulating AKT and extracellular signal-regulated kinase (ERK) signalling pathways.

Conclusions

Our findings uncover a critical role of the Bmal1-Junb-AKT/ERK axis in the circadian control of ConA-induced hepatitis and provide new insights into the prevention and treatment of AIH.

Impact and Implications

This study unveils a critical role of the Bmal1-Junb-AKT/ERK axis in the circadian control of ConA-induced liver injury, providing new insights into the prevention and treatment of immune-mediated hepatitis, including autoimmune hepatitis (AIH). The findings have scientific implications as they enhance our understanding of the circadian regulation of immune responses in liver diseases. Furthermore, clinically, this research offers opportunities for optimising treatment strategies in immune-mediated hepatitis by considering the timing of therapeutic interventions.

Involvement of brain-derived neurotrophic factor signaling in the pathogenesis of stress-related brain diseases

Neurotrophins including brain-derived neurotrophic factor, BDNF, have critical roles in neuronal differentiation, cell survival, and synaptic function in the peripheral and central nervous system. It is well known that a variety of intracellular signaling stimulated by TrkB, a high-affinity receptor for BDNF, is involved in the physiological and pathological neuronal aspects via affecting cell viability, synaptic function, neurogenesis, and cognitive function. As expected, an alteration of the BDNF/TrkB system is suspected to be one of the molecular mechanisms underlying cognitive decline in cognitive diseases and mental disorders. Recent evidence has also highlighted a possible link between the alteration of TrkB signaling and chronic stress. Furthermore, it has been demonstrated that downregulation of the BDNF/TrkB system and chronic stress have a role in the pathogenesis of Alzheimer's disease (AD) and mental disorders. In this review, we introduce current evidence showing a close relationship between the BDNF/TrkB system and the development of cognition impairment in stress-related disorders, and the possible contribution of the upregulation of the BDNF/TrkB system in a therapeutic approach against these brain diseases.

Immune-Neuroendocrine Patterning and Response to Stress. A latent profile analysis in the English Longitudinal Study of Ageing

Psychosocial stress exposure can disturb communication signals between the immune, nervous, and endocrine systems that are intended to maintain homeostasis. This dysregulation can provoke a negative feedback loop between each system that has high pathological risk. Here, we explore patterns of immune-neuroendocrine activity and the role of stress. Using data from the English Longitudinal Study of Ageing (ELSA), we first identified the latent structure of immune-neuroendocrine activity (indexed by high sensitivity C-reactive protein [CRP], fibrinogen [Fb], hair cortisol [cortisol], and insulin growth-factor-1 [IGF-1]), within a population-based cohort using latent profile analysis (LPA). Then, we determined whether life stress was associated with membership of different immune-neuroendocrine profiles. We followed 4,934 male and female participants with a median age of 65 years over a four-year period (2008-2012). A three-class LPA solution offered the most parsimonious fit to the underlying immune-neuroendocrine structure in the data, with 36%, 40%, and 24% of the population belonging to profiles 1 (low-risk), 2 (moderate-risk), and 3 (high-risk), respectively. After adjustment for genetic predisposition, sociodemographics, lifestyle, and health, higher exposure to stress was associated with a 61% greater risk of belonging to the high-risk profile (RRR: 1.61; 95%CI=1.23-2.12, p=0.001), but not the moderate-risk profile (RRR=1.10, 95%CI=0.89-1.35, p=0.401), as compared with the low-risk profile four years later. Our findings extend existing knowledge on psychoneuroimmunological processes, by revealing how inflammation and neuroendocrine activity cluster in a representative sample of older adults, and how stress exposure was associated with immune-neuroendocrine responses over time.

Targeting the Granulocytic Defense against A. fumigatus in Healthy Volunteers and Septic Patients

Neutrophil granulocytes (NGs) are among the key players in the defense against Aspergillus fumigatus (A. fumigatus). To better elucidate a pathophysiological understanding of their role and functions, we applied a human cell model using NGs from healthy participants and septic patients to evaluate their inhibitory effects on the growth of A. fumigatus ex vivo. Conidia of A. fumigatus (ATCC^® 204305) were co-incubated with NGs from healthy volunteers or septic patients for 16 h. A. fumigatus growth was measured by XTT assays with a plate reader. The inhibitory effect of NGs on 18 healthy volunteers revealed great heterogeneity. Additionally, growth inhibition was significantly stronger in the afternoon than the morning, due to potentially different cortisol levels. It is particularly interesting that the inhibitory effect of NGs was reduced in patients with sepsis compared to healthy controls. In addition, the magnitude of the NG-driven defense against A. fumigatus was highly variable among healthy volunteers. Moreover, daytime and corresponding cortisol levels also seem to have a strong influence. Most interestingly, preliminary experiments with NGs from septic patients point to a strongly diminished granulocytic defense against Aspergillus spp.

Clinical characterization of patients with bipolar disorder and a history of asthma: An exploratory study

INTRODUCTION

Bipolar disorder (BD) and asthma are leading causes of morbidity in the US and frequently co-occur.

OBJECTIVES

We evaluated the clinical features and comorbidities of patients with BD and a history of asthma.

METHODS

In a cross-sectional analysis from the Mayo Clinic Bipolar Biobank, we explored the clinical characteristics of the BD and an asthma phenotype and fitted a multivariable regression model to identify risk factors for asthma.

RESULTS

A total of 721 individuals with BD were included. From these, 140 (19%) had a history of asthma. In a multivariable model only sex and evening chronotype were significant predictors of asthma with the odds ratios and 95% confidence intervals being 1.65 (1.00, 2.72; p=0.05) and 1.99 (1.25, 3.17; p < 0.01), respectively. Individuals with asthma had higher odds of having other medical comorbidities after adjusting for age, sex, and site including hypertension (OR = 2.29 (95% CI 1.42, 3.71); p < 0.01), fibromyalgia (2.29 (1.16, 4.51); p=0.02), obstructive sleep apnea (2.03 (1.18, 3.50); p=0.01), migraine (1.98 (1.31, 3.00); p < 0.01), osteoarthritis (2.08 (1.20, 3.61); p < 0.01), and COPD (2.80 (1.14, 6.84); p=0.02). Finally, individuals currently on lithium were less likely to have a history of asthma (0.48 (0.32, 0.71); p < 0.01).

CONCLUSION

A history of asthma is common among patients with BD and is associated with being female and having an evening chronotype, as well as with increased odds of having other medical comorbidities. A lower likelihood of a history of asthma among those currently on lithium is an intriguing finding with potential clinical implications that warrants further study.

Current role and future perspectives of electroacupuncture in circadian rhythm regulation

In recent years, in-depth research on chronobiology has been conducted, and the circadian rhythm has become a new target for the treatment of diseases. Circadian rhythms are closely related to the normal physiological functions of organisms. Increasing evidence indicates that circadian rhythm disorders are the pathological basis of diseases such as sleep disorders, depression, cardiovascular diseases, and cancer. As an economical, safe, and effective treatment method, electroacupuncture has been widely used in clinical practice. In this paper, we summarize the current literature on electroacupuncture's regulation of circadian rhythm disorders and circadian clock genes. In addition, we briefly explore the optimization of electroacupuncture intervention programmes and the feasibility of implementing electroacupuncture intervention programmes at selected times in clinical practice. We conclude that electroacupuncture may have good application prospects in circadian rhythm regulation, but this conclusion needs to be confirmed by clinical trials.

Genome wide analysis of dexamethasone stimulated mineralization in human dental pulp cells by RNA sequencing

Human dental pulp cells (hDPCs) contain mesenchymal stem cells and are therefore indispensible for reparative dentin formation. Here, we present a pilot study of transcriptomic profiles of mineralized hDPCs isolated from sound human maxillary third molars. We observed altered gene expression of hDPCs between control (dexamethasone free) and experimental (dexamethasone 1 nm) groups. Differential expression analysis revealed up-regulation of several inflammation and mineralization-related genes in the experimental group. After a Gene Ontology analysis for predicting genes involved in biological process, cellular component and molecular function, we found enrichment of genes related to protein binding. Based on the results of Kyoto Encylopedia of Genes and Genomes pathway analysis, it is suggested up-regulated genes in mineralized hDPCs were mostly enriched in the mitogen-activated protein kinase (MAPK) signaling pathway, fluid shear stress and the atherosclerosis signaling pathway, etc. Importantly, Gene Set Enrichment Analysis revealed dexamethasone was positively related to the Janus kinase/signal transducer and activator of transcription, MAPK and Notch signaling pathway. Moreover, it was suggested that dexamethasone regulates signaling pathway in pluripotency of stem cells. Collectively, our work highlights transcriptome level gene regulation and intercellular interactions in mineralized hDPCs. The database produced in the present study paves the way for further investigations looking to explore genes that are involved in dental pulp cells mineralization.

Influence of hormones in multiple sclerosis: focus on the most important hormones

Hormonal imbalance may be an important factor in the severity of multiple sclerosis (MS) disease. In this context, hormone therapy has been shown to have immunoregulatory potential in various experimental approaches. There is increasing evidence of potentially beneficial effects of thyroid, melatonin, and sex hormones in MS models. These hormones may ameliorate the neurological impairment through immunoregulatory and neuroprotective effects, as well as by reducing oxidative stress. Expanding our knowledge of hormone therapy may be an effective step toward identifying additional molecular/cellular pathways in MS disease. In this review, we discuss the role of several important hormones in MS pathogenesis in terms of their effects on immunoregulatory aspects and neuroprotection.

Decreased mannan-binding lectin level in adults with hypopituitarism; dependence on appropriate hormone replacement therapies

Background

Mannan-binding lectin (MBL) is a main component of the lectin pathway of the complement system. Although there are some studies showing links between endocrine and immune systems, the ones concerning hypopituitarism are limited. The aim of this study was to check whether there is any association between blood MBL level and pituitary hormone deficiencies and whether this relationship is affected by appropriate hormone replacement therapies.

Methods

One hundred and twenty (120) inpatients, aged 18-92, were divided into two main groups, i.e. control individuals (21/120) and patients with pituitary diseases (99/120). The latter were diagnosed either with hypopituitarism (n=42) or with other pituitary diseases (not causing hypopituitarism) (n=57). Additionally, hypopituitary patients on appropriate replacement therapies (compensated hypopituitarism) were compared to patients on inappropriate replacement therapies (non-compensated hypopituitarism). Several parameters in blood serum were measured, including MBL level, pituitary and peripheral hormones and different biochemical parameters.

Results

Serum MBL level was significantly lower in patients with hypopituitarism comparing to controls (1358.97 ± 244.68 vs. 3199.30 ± 508.46, p<0.001) and comparing to other pituitary diseases (1358.97 ± 244.68 vs. 2388.12 ± 294.99, p=0.015) and this association was confirmed by univariate regression analysis. We evaluated the distribution of patients with relation to MBL level; there was a clear difference in this distribution between control individuals (among whom no subjects had MBL level <500 ng/mL) and patients with hypopituitarism (among whom 43% of patients had MBL level <500 ng/mL). Moreover, patients with non-compensated hypopituitarism had lower mean and median MBL levels comparing to patients with compensated hypopituitarism (1055.38 ± 245.73 vs. 2300.09 ± 579.93, p=0.027; 488.51 vs. 1951.89, p=0.009, respectively) and this association was confirmed in univariate regression analysis. However, mean and median MBL levels in patients with compensated hypopituitarism vs. controls did not differ significantly (2300.09 ± 579.93 vs. 3199.30 ± 508.46, p=0.294; 1951.90 vs. 2329.16; p=0.301, respectively).

Conclusion

Hypopituitarism in adults is associated with a decreased blood concentration of mannan-binding lectin, a phenomenon which does not exist in hypopituitary patients on the appropriate hormone replacement therapies. Therefore measurement of mannan-binding lectin level in patients with hypopituitarism may be considered as a parameter contributing to adjust optimal doses of hormone replacement therapies.

Circadian rhythms in psoriasis and the potential of chronotherapy in psoriasis management

The physiology and pathology of the skin are influenced by daily oscillations driven by a master clock located in the brain, and peripheral clocks in individual cells. The pathogenesis of psoriasis is circadian-rhythmic, with flares of disease and symptoms such as itch typically being worse in the evening/night-time. Patients with psoriasis have changes in circadian oscillations of blood pressure and heart rate, supporting wider circadian disruption. In addition, shift work, a circadian misalignment challenge, is associated with psoriasis. These features may be due to underlying circadian control of key effector elements known to be relevant in psoriasis such as cell cycle, proliferation, apoptosis and inflammation. Indeed, peripheral clock pathology may lead to hyperproliferation of keratinocytes in the basal layers, insufficient apoptosis of differentiating keratinocytes in psoriatic epidermis, dysregulation of skin-resident and migratory immune cells and modulation of angiogenesis through circadian oscillation of vascular endothelial growth factor A (VEGF-A) in epidermal keratinocytes. Chronotherapeutic effects of topical steroids and topical vitamin D analogues have been reported, suggesting that knowledge of circadian phase may improve the efficacy, and therapeutic index of treatments for psoriasis. In this viewpoint essay, we review the current literature on circadian disruption in psoriasis. We explore the hypothesis that psoriasis is circadian-driven. We also suggest that investigation of the circadian components specific to psoriasis and that the in vitro investigation of circadian regulation of psoriasis will contribute to the development of a novel chronotherapeutic treatment strategy for personalised psoriasis management. We also propose that circadian oscillations of VEGF-A offer an opportunity to enhance the efficacy and tolerability of a novel anti-VEGF-A therapeutic approach, through the timed delivery of anti-VEGF-A drugs.

Profound Effects of Dexamethasone on the Immunological State, Synthesis and Secretion Capacity of Human Testicular Peritubular Cells

The functions of human testicular peritubular cells (HTPCs), forming a small compartment located between the seminiferous epithelium and the interstitial areas of the testis, are not fully known but go beyond intratesticular sperm transport and include immunological roles. The expression of the glucocorticoid receptor (GR) indicates that they may be regulated by glucocorticoids (GCs). Herein, we studied the consequences of the GC dexamethasone (Dex) in cultured HTPCs, which serves as a unique window into the human testis. We examined changes in cytokines, mainly by qPCR and ELISA. A holistic mass-spectrometry-based proteome analysis of cellular and secreted proteins was also performed. Dex, used in a therapeutic concentration, decreased the transcript level of proinflammatory cytokines, e.g., IL6, IL8 and MCP1. An siRNA-mediated knockdown of GR reduced the actions on IL6. Changes in IL6 were confirmed by ELISA measurements. Of note, Dex also lowered GR levels. The proteomic results revealed strong responses after 24 h (31 significantly altered cellular proteins) and more pronounced ones after 72 h of Dex exposure (30 less abundant and 42 more abundant cellular proteins). Dex also altered the composition of the secretome (33 proteins decreased, 13 increased) after 72 h. Among the regulated proteins were extracellular matrix (ECM) and basement membrane components (e.g., FBLN2, COL1A2 and COL3A1), as well as PTX3 and StAR. These results pinpoint novel, profound effects of Dex in HTPCs. If transferrable to the human testis, changes specifically in ECM and the immunological state of the testis may occur in men upon treatment with Dex for medical reasons.

Time of Day of BNT162b2 COVID-19 Immunization Affects Total SARS-CoV-2 Antibody Levels but Not Neutralizing Activity

To examine whether immunization time affects the immune responses elicited by the BNT162b2 COVID-19 vaccine, we investigated the possible association between total SARS-CoV-2 spike protein receptor binding domain (TAbs-RBD) and neutralizing (NAbs-RBD) antibodies with vaccination time. A cohort of 468 healthcare workers (mean age [±SD]: 48 [±13] years), were included in the study. One month after the second dose, healthcare workers who were vaccinated between 1500-2200 h had higher TAbs-RBD compared to 0700-1100 h and 1100-1500 h (p = 0.006). One month after the third dose, healthcare workers who were vaccinated between 0700-1100 h and 1500-2200 h had significantly higher TAbs-RBD compared to 1100-1500 h (p = 0.034). However, no association of NAbs-RBD with vaccination time was detected after each of the 3 doses (p > 0.4). Despite the possible effect of BNT162b2 vaccination time in TAbs-RBD levels, possibly due to rhythmic expression of clock genes, neutralizing activity was not associated with vaccination time and, therefore, further investigation is required.

Interactions between nuclear receptors glucocorticoid receptor α and peroxisome proliferator-activated receptor α form a negative feedback loop

Both nuclear receptors glucocorticoid receptor α (GRα) and peroxisome proliferator-activated receptor α (PPARα) are involved in energy and lipid metabolism, and possess anti-inflammation effects. Previous studies indicate that a regulatory loop may exist between them. In vivo and in vitro studies showed that glucocorticoids stimulate hepatic PPARα expression via GRα at the transcriptional level. This stimulation of PPARα by GRα has physiological relevance and PPARα is involved in many glucocorticoid-induced pathophysiological processes, including gluconeogenesis and ketogenesis during fasting, insulin resistance, hypertension and anti-inflammatory effects. PPARα also synergizes with GRα to promote erythroid progenitor self-renewal. As the feedback, PPARα inhibits glucocorticoid actions at pre-receptor and receptor levels. PPARα decreases glucocorticoid production through inhibiting the expression and activity of type-1 11β-hydroxysteroid dehydrogenase, which converts inactive glucocorticoids to active glucocorticoids at local tissues, and also down-regulates hepatic GRα expression, thus forming a complete and negative feedback loop. This negative feedback loop sheds light on prospective multi-drug therapeutic treatments in inflammatory diseases through a combination of glucocorticoids and PPARα agonists. This combination may potentially enhance the anti-inflammatory effects while alleviating side effects on glucose and lipid metabolism due to GRα activation. More investigations are needed to clarify the underlying mechanism and the relevant physiological or pathological significance of this regulatory loop.

Regulated necrosis, a proinflammatory cell death, potentially counteracts pathogenic infections

Since the discovery of cell apoptosis, other gene-regulated cell deaths are gradually appreciated, including pyroptosis, ferroptosis, and necroptosis. Necroptosis is, so far, one of the best-characterized regulated necrosis. In response to diverse stimuli (death receptor or toll-like receptor stimulation, pathogenic infection, or other factors), necroptosis is initiated and precisely regulated by the receptor-interacting protein kinase 3 (RIPK3) with the involvement of its partners (RIPK1, TRIF, DAI, or others), ultimately leading to the activation of its downstream substrate, mixed lineage kinase domain-like (MLKL). Necroptosis plays a significant role in the host's defense against pathogenic infections. Although much has been recognized regarding modulatory mechanisms of necroptosis during pathogenic infection, the exact role of necroptosis at different stages of infectious diseases is still being unveiled, e.g., how and when pathogens utilize or evade necroptosis to facilitate their invasion and how hosts manipulate necroptosis to counteract these detrimental effects brought by pathogenic infections and further eliminate the encroaching pathogens. In this review, we summarize and discuss the recent progress in the role of necroptosis during a series of viral, bacterial, and parasitic infections with zoonotic potentials, aiming to provide references and directions for the prevention and control of infectious diseases of both human and animals.

Corticosteroid Treatment-Resistance in Myasthenia Gravis

Chronic, high-dose, oral prednisone has been the mainstay of myasthenia gravis treatment for decades and has proven to be highly beneficial in many, toxic in some way to all, and not effective in a significant minority. No patient characteristics or biomarkers are predictive of treatment response leading to many patients suffering adverse effects with no benefit. Presently, measurements of treatment response, whether taken from clinician or patient perspective, are appreciated to be limited by lack of good correlation, which then complicates correlation to biological measures. Treatment response may be limited because disease mechanisms are not influenced by corticosteroids, limits on dosage because of adverse effects, or individual differences in corticosteroids. This review evaluates potential mechanisms that underlie lack of response to glucocorticoids in patients with myasthenia gravis.

Transcriptome analysis of the early stage ifnlr1-mutant zebrafish indicates the immune response to auditory dysfunction

BACKGROUND

IFNLR1 has been recently identified to be related to autosomal dominant nonsyndromic sensorineural hearing loss (ADNSHL). It is reported to be expressed in the inner ear of mice and the lateral line of zebrafish. However, it remains unclear how defects in this gene lead to hearing loss.

OBJECTIVES

To elucidate the global gene expression changes in zebrafish when the expression of ifnlr1 is downregulated.

METHODS

Transcriptome analysis was performed on ifnlr1 morpholino knockdown zebrafish and the control zebrafish using RNA-seq technology.

RESULTS

The results show that 262 differentially expressed genes (DEGs) were up-regulated while 146 DEGs were down-regulated in the E4I4-Mo zebrafish larvae compared to the control-Mo. Six pathways were significantly enriched, including steroid biosynthesis pathway, adipocytokine signaling pathway, cytokine-cytokine receptor interaction pathway, p53 signaling pathway, AGE-RAGE signaling pathway in diabetic complications, and terpenoid backbone biosynthesis pathway. Among them, three pathways (steroid biosynthesis pathway, cytokine-cytokine receptor interaction pathway and p53 signaling pathway) are immune-associated.

CONCLUSIONS

The transcriptome analysis results contribute to the groundwork for future research on the pathogenesis of IFNLR1-associated hearing loss.