Molecular mechanisms of glucocorticoid action and selective glucocorticoid receptor agonists

Glucocorticoid receptors orchestrate a convergence of host and cellular stress signals in triple negative breast cancer

Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer that lacks expression of the nuclear steroid receptors that bind estrogens (ER) and progestogens (PRs) and does not exhibit HER2 (Human epidermal growth factor 2) receptor overexpression. Even in the face of initially effective chemotherapies, TNBC patients often relapse. One primary cause for therapy-resistant tumor progression is the activation of cellular stress signaling pathways. The glucocorticoid receptor (GR), a corticosteroid-activated transcription factor most closely related to PR, is a mediator of both endocrine/host stress and local tumor microenvironment (TME)-derived and cellular stress responses. Interestingly, GR expression is associated with a good prognosis in ER+ breast cancer but predicts poor prognosis in TNBC. Classically, GR's transcriptional activity is regulated by circulating glucocorticoids. Additionally, GR is regulated by ligand-independent signaling events. Notably, the stress-activated protein kinase, p38 MAP kinase, phosphorylates GR at serine 134 (Ser134) in response to TME-derived growth factors and cytokines, including HGF and TGFβ1. Phospho-Ser134-GR (p-Ser134-GR) associates with cytoplasmic and nuclear signaling molecules, including 14-3-3ζ, aryl hydrocarbon receptors (AhR), and hypoxia-inducible factors (HIFs). Phospho-GR/HIF-containing transcriptional complexes upregulate gene sets whose protein products include the components of inducible oncogenic signaling pathways (PTK6) that further promote cancer cell survival, chemoresistance, altered metabolism, and migratory/invasive behavior in TNBC. Recent studies have implicated liganded p-Ser134-GR (p-GR) in dexamethasone-mediated upregulation of genes related to TNBC cell motility and dysregulated metabolism. Herein, we review the tumor-promoting roles of GR and discuss how both ligand-dependent and ligand-independent/stress signaling-driven inputs to p-GR converge to orchestrate metastatic TNBC progression.

Merging Natural Product Structures with Pharmaceutical Leads: Unnatural Enantiomers of Estranes as Glucocorticoid Receptor Modulators That Suppress TNF-α and IL-6 Release

Natural products are widely recognized as valuable starting points for the development of therapeutics, with synthetic tetracyclic triterpenoids (e.g., steroids) being the most well represented among the drugs approved by the Food and Drug Administration. Here, recently developed synthetic tools for concise, asymmetric, and convergent construction of steroidal systems are leveraged to drive a program aimed at identifying novel glucocorticoid receptor (GR) modulators. While glucocorticoids have been extensively used as anti-inflammatory agents, they are plagued by severe side effects that include bone loss, muscle wasting, and metabolic disease. Ultimately, a program targeting the unnatural enantiomers of estranes (ent-estranes) that are practically inaccessible from natural product derivatization (semisynthesis) has resulted in the identification of a new class of potent dissociated GR modulators. We identify several leads with >99% efficacy as antagonists of GR trans-activation (potency within 10-fold of that of mifepristone) and further characterize examples that also inhibit release of pro-inflammatory cytokines IL-6 and TNF-α.

Genetically Encoded Trensor Circuits Report HeLa Cell Treatment with Polyplexed Plasmid DNA and Small-Molecule Transfection Modulators

HeLa cell transfection with plasmid DNA (pDNA) is widely used to materialize biologicals and as a preclinical test of nucleic acid-based vaccine efficacy. We sought to genetically encode mammalian transfection sensor (Trensor) circuits and test their utility in HeLa cells for detecting molecules and methods for their propensity to influence transfection. We intended these Trensor circuits to be triggered if their host cell was treated with polyplexed pDNA or certain small-molecule modulators of transfection. We prioritized three promoters, implicated by others in feedback responses as cells import and process foreign material and stably integrated each into the genomes of three different cell lines, each upstream of a green fluorescent protein (GFP) open reading frame within a transgene. All three Trensor circuits showed an increase in their GFP expression when their host HeLa cells were incubated with pDNA and the degraded polyamidoamine dendrimer reagent, SuperFect. We next experimentally demonstrated the modulation of PEI-mediated HeLa cell transient transfection by four different small molecules, with Trichostatin A (TSA) showing the greatest propensity to boost transgene expression. The Trensor circuit based on the TRA2B promoter (Trensor-T) was triggered by incubation with TSA alone and not the other three small molecules. These data suggest that mammalian reporter circuits could enable low-cost, high-throughput screening to identify novel transfection methods and reagents without the need to perform actual transfections requiring costly plasmids or expensive fluorescent labels.

Targeted Treatments for Myasthenia Gravis in Children and Adolescents

Myasthenia gravis (MG) is an antibody-mediated disorder of the neuromuscular junction affecting children and adults. MG is a treatable condition with most patients requiring immunosuppression for disease control and/or remission. Juvenile myasthenia gravis (JMG) is rare in comparison with adult-onset MG but given the same underlying pathophysiology, treatment strategies are similar to those in adults. Until recently, there were only a few randomised controlled trials (RCTs) for MG treatments in adults and none in children, and management strategies were primarily based on expert consensus. In addition, treatment options for refractory MG cases have been severely limited, resulting in poor long-term quality of life in such patients due to the significant disease burden. Recently, there have been several RCTs focussing on novel therapeutic strategies with potentially promising outcomes, suggesting a change in MG management over the coming years and access to more effective and faster-acting drugs for MG patients. This paper will review current and new MG treatments including efgartigimod, eculizumab, rozanolixizumab, ravulizumab, and zilucoplan, with a focus on juvenile myasthenia gravis.

Evaluation of Cordyceps militaris steroids as anti-inflammatory agents to combat the Covid-19 cytokine storm: a bioinformatics and structure-based drug designing approach

Since the SARS-CoV-2 epidemic, researchers have been working on figuring out ways to tackle multi-organ failure and hyperinflation, which are brought on by a cytokine storm. Angiotensin-converting enzyme 2 (ACE2), a SARS-CoV-2 spike glycoprotein's cellular receptor, is involved in complicated molecular processes that result in hyperinflammation. Cordyceps militaris is one of the traditional Chinese medicines that is used as an immune booster, and it has exhibited efficacy in lowering blood glucose levels, seminal emissions, and infertility. In the current study, we explored the potential of Cordyceps militaris steroids as key agents in managing the anger of cytokine storm in Covid-19 using network ethnopharmacological techniques and structure-based drug designing approaches. The steroids present in Cordyceps militaris were initially screened against the targets involved in inflammatory pathways. The results revealed that out of 16 steroids, 5 may be effective against 17 inflammatory pathways by targeting 11 pathological proteins. Among the five steroids, beta-sitosterol, Cholest-5-en-3β-ol, 3β, and 7α-Dihydroxycholest-5-ene were found to interact with thrombin (F2), an important protein reported to reduce the severity of inflammatory mediators and Cholest-4-en-3-one was found to target Glucocorticoid receptor (NR3C1). The top docked steroid displayed key interactions with both targets, which retained key interactions throughout the 100 ns simulation period. These compounds were also shown high binding free energy scores in water swap studies. Based on obtained results the current study suggests the use of Cordyceps militaris as an add-on therapy that may reduce the progression of inflammatory co-morbidities among patients infected with SARS-CoV-2.Communicated by Ramaswamy H. Sarma.

Cortisol in metabolic syndrome

Cortisol, a stress hormone, plays a crucial role in regulating metabolic, hemodynamic, inflammatory, and behavioral processes. Its secretion is governed by the hypothalamic-pituitary-adrenal axis. However, prolonged activation of this axis and increased cortisol bioavailability in tissues can result in detrimental metabolic effects. Chronic exposure to excessive cortisol is associated with insulin resistance and visceral obesity, both significant contributors to metabolic syndrome. This review delves into the regulation of the hypothalamic-pituitary-adrenal axis, the molecular mechanisms underlying cortisol synthesis and its actions, as well as the key factors influencing cortisol bioavailability. Furthermore, it provides a summary of available clinical research data on the involvement of cortisol in metabolic syndrome, alongside a discussion on the various biomatrices used for cortisol measurement in clinical settings.

Cellular Immunobiology and Molecular Mechanisms in Alloimmunity-Pathways of Immunosuppression

Current maintenance immunosuppression commonly comprises a synergistic combination of tacrolimus as calcineurin inhibitor (CNI), mycophenolic acid, and glucocorticoids. Therapy is often individualized by steroid withdrawal or addition of belatacept or inhibitors of the mechanistic target of rapamycin. This review provides a comprehensive overview of their mode of action, focusing on the cellular immune system. The main pharmacological action of CNIs is suppression of the interleukin-2 pathway that leads to inhibition of T cell activation. Mycophenolic acid inhibits the purine pathway and subsequently diminishes T and B cell proliferation but also exerts a variety of effects on almost all immune cells, including inhibition of plasma cell activity. Glucocorticoids exert complex regulation via genomic and nongenomic mechanisms, acting mainly by downregulating proinflammatory cytokine signatures and cell signaling. Belatacept is potent in inhibiting B/T cell interaction, preventing formation of antibodies; however, it lacks the potency of CNIs in preventing T cell-mediated rejections. Mechanistic target of rapamycin inhibitors have strong antiproliferative activity on all cell types interfering with multiple metabolic pathways, partly explaining poor tolerability, whereas their superior effector T cell function might explain their benefits in the case of viral infections. Over the past decades, clinical and experimental studies provided a good overview on the underlying mechanisms of immunosuppressants. However, more data are needed to delineate the interaction between innate and adaptive immunity to better achieve tolerance and control of rejection. A better and more comprehensive understanding of the mechanistic reasons for failure of immunosuppressants, including individual risk/benefit assessments, may permit improved patient stratification.

Transcription factors in the development and treatment of immune disorders

Immune function is highly controlled at the transcriptional level by the binding of transcription factors (TFs) to promoter and enhancer elements. Several TF families play major roles in immune gene expression, including NF-κB, STAT, IRF, AP-1, NRs, and NFAT, which trigger anti-pathogen responses, promote cell differentiation, and maintain immune system homeostasis. Aberrant expression, activation, or sequence of isoforms and variants of these TFs can result in autoimmune and inflammatory diseases as well as hematological and solid tumor cancers. For this reason, TFs have become attractive drug targets, even though most were previously deemed "undruggable" due to their lack of small molecule binding pockets and the presence of intrinsically disordered regions. However, several aspects of TF structure and function can be targeted for therapeutic intervention, such as ligand-binding domains, protein-protein interactions between TFs and with cofactors, TF-DNA binding, TF stability, upstream signaling pathways, and TF expression. In this review, we provide an overview of each of the important TF families, how they function in immunity, and some related diseases they are involved in. Additionally, we discuss the ways of targeting TFs with drugs along with recent research developments in these areas and their clinical applications, followed by the advantages and disadvantages of targeting TFs for the treatment of immune disorders.

Short-term exposure to dexamethasone at environmentally relevant concentrations impairs embryonic development in Cyprinus carpio: Bioconcentration and alteration of oxidative stress-related gene expression patterns

In recent years and as a result of the Covid-19 pandemic, the consumption of dexamethasone (DXE) has increased. This favors that this corticosteroid is highly released in aquatic environments, generating deleterious effects in aquatic organisms. The information on the toxic effects of DXE in the environment is still limited. Thus, the objective of this work was to determine whether DXE at short-term exposure can cause alterations to embryonic development and alteration of oxidative stress-related gene expression patterns in Cyprinus carpio. For this purpose, common carp embryos (2 hpf) were exposed to realistic concentrations of DXE until 96 hpf. Alterations to embryonic development were evaluated at 12, 24, 48, 72 and 96 hpf. In addition, oxidative stress in carp embryos at 72 and 96 hpf was evaluated by cellular oxidation biomarkers (lipoperoxidation level, hydroperoxide and carbonyl protein content) and antioxidant enzymes activities (superoxide dismutase and catalase). Oxidative stress-related gene expression (sod, cat and gpx1) was also evaluated. Our results showed that DXE concentrations above 35 ng/L are capable of producing alterations to embryonic development in 50 % of the embryo population. Furthermore, DXE was able to induce alterations such as scoliosis, hypopigmentation, craniofacial malformations, pericardial edema and growth retardation, leading to the death of half of the population at 50 ng/L of DXE. Concerning oxidative stress, the results demonstrated that DXE induce oxidative damage on the embryos of C. carpio. In conclusion, DXE is capable of altering embryonic development and generating oxidative stress in common carp C. carpio.

Diverse roles of glucocorticoids in the ruminant mammary gland: modulation of mammary growth, milk production, and mastitis

As endocrine hormones, glucocorticoids (GCs) play a pivotal role in numerous physiological processes, including mammary growth and lactation, circulatory metabolism, and responses to external stimuli. In the dairy industry, milk production from cows or goats is important for newborns and economic benefits. However, the milk yields from ruminant animals are always affected by the extent of mammary development, mammary disease, stress, or changes in metabolism. Thus, it is necessary to clarify how GCs changes in ruminants affect ruminant mammary gland function and mammary disease. This review summarizes the findings identifying that GCs modulate mammary gland development before lactation, but the stress-induced excessive release of GCs leads to milk production loss. In addition, the manner of GCs release may change under different concentrations of metabolites or during mastitis or inflammatory challenge. Nevertheless, exogenous GCs administration to animals may alleviate the clinical symptoms of mastitis. This review demonstrates that GCs offer a fascinating contribution to both physiologic and pathogenic conditions of the mammary gland in ruminant animals. Characterizing and understanding these changes or functions of endogenous and exogenous GCs in animals will be crucial for developing more endocrine regulators and therapies for improving milk production in ruminants.

In vitro, in vivo, and in silico evaluation of the glucocorticoid receptor antagonist activity of 3,6-dibromocarbazole

3,6-Dibromocarbazole is a novel environmental contaminant which is currently detected in several environmental media worldwide. This work aims to investigate the anti-glucocorticoid potency and endocrine disrupting effects of 3,6-dibromocarbazole. In vitro experiments indicated that 3,6-dibromocarbazole possessed glucocorticoid receptor (GR) antagonistic activity and inhibited dexamethasone-induced GR nuclear translocation. 3,6-Dibromocarbazole reduced the expression levels of glucocorticoid responsive genes including glucose-6-phosphatase (G6Pase), phosphoenolpyruvate carboxykinase (PEPCK), fatty acid synthase (FAS), and tyrosine aminotransferase (TAT), and further disrupted the protein expression of two key enzymes PEPCK and FAS in gluconeogenesis. In vivo experiments showed that 3,6-dibromocarbazole induced abnormal development of zebrafish embryos and disrupted the major neurohormones involved in activation of hypothalamic-pituitary-adrenocortical (HPA) axis in zebrafish larvae. The results of molecular docking and molecular dynamics simulation contributed to explain the antagonistic effect of 3,6-dibromocarbazole. Taken together, this work identified 3,6-dibromocarbazole as a GR antagonist, which might exert endocrine disrupting effects by interfering the pathway of gluconeogenesis.

The role of hormones in the pathogenesis and treatment mechanisms of delirium in ICU: The past, the present, and the future

Delirium is an acute brain dysfunction. As one of the common psychiatric disorders in ICU, it can seriously affect the prognosis of patients. Hormones are important messenger substances found in the human body that help to regulate and maintain the function and metabolism of various tissues and organs. They are also one of the most commonly used drugs in clinical practice. Recent evidences suggest that aberrant swings in cortisol and non-cortisol hormones might induce severe cognitive impairment, eventually leading to delirium. However, the role of hormones in the pathogenesis of delirium still remains controversial. This article reviews the recent research on risk factors of delirium and the association between several types of hormones and cognitive dysfunction. These mechanisms are expected to offer novel ideas and clinical relevance for the treatment and prevention of delirium.

Residual effects of intra-articular betamethasone and triamcinolone acetonide in an equine acute synovitis model

BACKGROUND

Intra-articular (IA) corticosteroids are regularly used in equine athletes for the control of joint inflammation.

OBJECTIVES

The goal of this study was to use an acute synovitis inflammation model to determine the residual effects of IA betamethasone and triamcinolone acetonide on various inflammatory parameters and lameness.

STUDY DESIGN

Crossover randomised trial.

METHODS

Five mixed-breed, 2-year-old horses were randomly allocated to an IA treatment of the radiocarpal joint with 9 mg of either betamethasone or triamcinolone acetonide. Two weeks following treatment, horses were injected with 1 μg of lipopolysaccharide (LPS) diluted in 1 ml of saline. Following LPS injection, horses were crossed-over and both sets of injections were repeated after a washout period. Blood samples were collected at multiple time points for mRNA analysis, as well as serum amyloid A (SAA) and cortisol determination. At each time point, lameness was also subjectively scored. Additional injections with saline-only or LPS-only (twice) were conducted as negative and positive controls, respectively. Two-way repeated measures analysis of variance was used to analyse all data.

RESULTS

Corticosteroid-only treatments result in significant mRNA expression differences, as well as significant and prolonged cortisol suppression. Following LPS injection, there was a residual treatment effect with triamcinolone evidenced by a significant treatment effect on IL-6 and PTGS1 (cyclooxygenase-1), lameness, SAA and cortisol concentrations, while only IL-6 expression was affected by betamethasone.

MAIN LIMITATIONS

The acute synovitis model used here results in significant inflammation and is not representative of the low-grade inflammation seen with typical joint disease and residual anti-inflammatory effects may be more profound in naturally occurring joint disease.

CONCLUSIONS

Current regulatory guidelines may be insufficient if the concern is residual anti-inflammatory effects. Additionally, intra-articular corticosteroid administration is not without risk, as evidenced by a significant suppression of serum cortisol concentration and, as such, the benefits of their administration should be weighed against those risks.

Phosphorylation of glucocorticoid receptor induced by 16-kauren-2-beta-18, 19-triol decreases expression of Melanophilin through JNK signalling

16-kauren-2-beta-18, 19-triol (16-kauren) is a natural diterpenoid substance derived from Asteraceae psiadia punctulata, a small tropical shrub in Africa and Asia, and it can reduce Mlph expression without affecting the expression of Rab27a and MyoVa in melanocytes. Melanophilin (Mlph) is an important linker protein in the melanosome transport process. However, the signal transduction pathway for the regulation of Mlph expression has not been fully established. We examined the mechanism of 16-kauren on Mlph expression. Murine melan-a melanocytes were used for in vitro analysis. Western blot analysis, quantitative real-time polymerase chain reaction, and luciferase assay were performed. The inhibition of Mlph expression by 16-kauren-2β-18,19-triol (16-kauren) occurs through the JNK signal and is reversed following glucocorticoid receptor (GR) activation by dexamethasone (Dex). Especially, 16-kauren activates JNK and c-jun signalling, part of the MAPK pathway, with subsequent Mlph repression. When the JNK signal is weakened by siRNA, the inhibition of Mlph expression by 16-kauren was not seen. JNK activation by 16-kauren induces GR phosphorylation, which leads to Mlph repression. These results demonstrate that 16-kauren regulates Mlph expression through the phosphorylation of GR via the JNK signalling pathway.

UBR5 forms ligand-dependent complexes on chromatin to regulate nuclear hormone receptor stability

Nuclear hormone receptors (NRs) are ligand-binding transcription factors that are widely targeted therapeutically. Agonist binding triggers NR activation and subsequent degradation by unknown ligand-dependent ubiquitin ligase machinery. NR degradation is critical for therapeutic efficacy in malignancies that are driven by retinoic acid and estrogen receptors. Here, we demonstrate the ubiquitin ligase UBR5 drives degradation of multiple agonist-bound NRs, including the retinoic acid receptor alpha (RARA), retinoid x receptor alpha (RXRA), glucocorticoid, estrogen, liver-X, progesterone, and vitamin D receptors. We present the high-resolution cryo-EMstructure of full-length human UBR5 and a negative stain model representing its interaction with RARA/RXRA. Agonist ligands induce sequential, mutually exclusive recruitment of nuclear coactivators (NCOAs) and UBR5 to chromatin to regulate transcriptional networks. Other pharmacological ligands such as selective estrogen receptor degraders (SERDs) degrade their receptors through differential recruitment of UBR5 or RNF111. We establish the UBR5 transcriptional regulatory hub as a common mediator and regulator of NR-induced transcription.

Glucocorticoid Treatment in Acute Respiratory Distress Syndrome: An Overview on Mechanistic Insights and Clinical Benefit

Acute lung injury/acute respiratory distress syndrome (ALI/ARDS), triggered by various pathogenic factors inside and outside the lungs, leads to diffuse lung injury and can result in respiratory failure and death, which are typical clinical critical emergencies. Severe acute pancreatitis (SAP), which has a poor clinical prognosis, is one of the most common diseases that induces ARDS. When SAP causes the body to produce a storm of inflammatory factors and even causes sepsis, clinicians will face a two-way choice between anti-inflammatory and anti-infection objectives while considering the damaged intestinal barrier and respiratory failure, which undoubtedly increases the difficulty of the diagnosis and treatment of SAP-ALI/ARDS. For a long time, many studies have been devoted to applying glucocorticoids (GCs) to control the inflammatory response and prevent and treat sepsis and ALI/ARDS. However, the specific mechanism is not precise, the clinical efficacy is uneven, and the corresponding side effects are endless. This review discusses the mechanism of action, current clinical application status, effectiveness assessment, and side effects of GCs in the treatment of ALI/ARDS (especially the subtype caused by SAP).

A preclinical secondary pharmacology resource illuminates target-adverse drug reaction associations of marketed drugs

In vitro secondary pharmacology assays are an important tool for predicting clinical adverse drug reactions (ADRs) of investigational drugs. We created the Secondary Pharmacology Database (SPD) by testing 1958 drugs using 200 assays to validate target-ADR associations. Compared to public and subscription resources, 95% of all and 36% of active (AC50 < 1 µM) results are unique to SPD, with bias towards higher activity in public resources. Annotating drugs with free maximal plasma concentrations, we find 684 physiologically relevant unpublished off-target activities. Furthermore, 64% of putative ADRs linked to target activity in key literature reviews are not statistically significant in SPD. Systematic analysis of all target-ADR pairs identifies several putative associations supported by publications. Finally, candidate mechanisms for known ADRs are proposed based on SPD off-target activities. Here we present a freely-available resource for benchmarking ADR predictions, explaining phenotypic activity and investigating clinical properties of marketed drugs.

Network-based identification and prioritization of key transcriptional factors of diabetic kidney disease

Diabetic nephropathy (DN) is one of the most established microvascular complications of diabetes and a key cause of end-stage renal disease. It is well established that gene susceptibility to DN plays a critical role in disease pathophysiology. Therefore, many genetic studies have been performed to categorize candidate genes in prominent diabetic cohorts, aiming to investigate DN pathogenesis and etiology. In this study, we performed a meta-analysis on the expression profiles of GSE1009, GSE30122, GSE96804, GSE99340, GSE104948, GSE104954, and GSE111154 to identify critical transcriptional factors associated with DN progression. The analysis was conducted for all individual datasets for each kidney tissue (glomerulus, tubules, and kidney cortex). We identified distinct clusters of susceptibility genes that were dysregulated in a renal compartment-specific pattern. Further, we recognized a small but a closely connected set of these susceptibility genes enriched for podocyte differentiation, several of which were characterized as genes encoding critical transcriptional factors (TFs) involved in DN development and podocyte function. To validate the role of identified TFs in DN progression, we functionally validated the three main TFs (DACH1, LMX1B, and WT1) identified through differential gene expression and network analysis using the hyperglycemic zebrafish model. We report that hyperglycemia-induced altered gene expression of the key TF genes leads to morphological abnormalities in zebrafish glomeruli, pronephric tubules, proximal and distal ducts. This study demonstrated that altered expression of these TF genes could be associated with hyperglycemia-induced nephropathy and, thus, aids in understanding the molecular drivers, essential genes, and pathways that trigger DN initiation and development.

Consensus document of the Spanish Group for the Study of the Glomerular Diseases (GLOSEN) for the diagnosis and treatment of lupus nephritis

A significant number of patients with systemic lupus erythematosus (between 20% and 60% according to different reported series) develop lupus nephritis in the course of its evolution, which directly influences their quality of life and vital prognosis. In recent years, the greater knowledge about the pathogenesis of systemic lupus and lupus nephritis has allowed relevant advances in the diagnostic approach and treatment of these patients, achieving the development of drugs specifically aimed at blocking key pathogenic pathways of the disease. Encouragingly, these immunomodulatory agents have shown in well-powered, randomized clinical trials good clinical efficacy in the medium-term, defined as proteinuria remission and preservation of kidney function, with an acceptable safety profile and good patient tolerability. All this has made it possible to reduce the use of corticosteroids and other potentially more toxic therapies, as well as to increase the use of combined therapies. The present consensus document carried out by the Glomerular Diseases Working Group of the Spanish Society of Nephrology (GLOSEN), collects in a practical and summarized, but rigorous way, the best currently available evidence about the diagnosis, treatment, and follow-up of lupus nephritis patients, including cases of special situations, with the main objective of providing updated information and well-founded clinical recommendations to treating physicians, to improve the diagnostic and therapeutic approach to our patients.

Tight Junctions, the Epithelial Barrier, and Toll-like Receptor-4 During Lung Injury

Lung epithelium is constantly exposed to the environment and is critically important for the orchestration of initial responses to infectious organisms, toxins, and allergic stimuli, and maintenance of normal gaseous exchange and pulmonary function. The integrity of lung epithelium, fluid balance, and transport of molecules is dictated by the tight junctions (TJs). The TJs are formed between adjacent cells. We have focused on the topic of the TJ structure and function in lung epithelial cells. This review includes a summary of the last twenty years of literature reports published on the disrupted TJs and epithelial barrier in various lung conditions and expression and regulation of specific TJ proteins against pathogenic stimuli. We discuss the molecular signaling and crosstalk among signaling pathways that control the TJ structure and function. The Toll-like receptor-4 (TLR4) recognizes the pathogen- and damage-associated molecular patterns released during lung injury and inflammation and coordinates cellular responses. The molecular aspects of TLR4 signaling in the context of TJs or the epithelial barrier are not fully known. We describe the current knowledge and possible networking of the TLR4-signaling with cellular and molecular mechanisms of TJs, lung epithelial barrier function, and resistance to treatment strategies.

Pterostilbene-isothiocyanate impedes RANK/TRAF6 interaction to inhibit osteoclastogenesis, promoting osteogenesis in vitro and alleviating glucocorticoid induced osteoporosis in rats

Prolonged glucocorticoid treatment often leads to glucocorticoid-induced osteoporosis (GIOP), a common iatrogenic complication. This study has explored the anti-osteoporotic potential of semi-synthetic compound, pterostilbene isothiocyanate (PTER-ITC) in GIOP rat model and bone formation potential in vitro. Dysregulated bone-remodelling leads to osteoporosis. PTER-ITC has shown anti-osteoclastogenic activity in vitro. However, its molecular target remains unidentified, which has been explored in this study through in silico and experimental approaches. Alizarin Red S and von-Kossa staining, and alkaline phosphatase (ALP) activity showed the osteogenic differentiation potential of PTER-ITC in pre-osteoblastic mouse MC3T3-E1 and human hFOB 1.19 cells, further, confirmed through the expressions of osteogenic markers at transcriptional (RT-qPCR) and translational (immunoblotting) levels. The anti-osteoclastogenic property of PTER-ITC was confirmed through inhibition of actin ring formation in mouse RAW 264.7 and human THP-1 macrophagic cells. Molecular docking and molecular dynamic simulation showed that PTER-ITC inhibited the crucial osteoclastogenic RANK/TRAF6 interaction, which was further confirmed biochemically through co-immunoprecipitation assay. Osteoporotic bone architecture [validated through scanning electron microscopy (SEM), X-ray radiography, and micro-computed tomography (µ-CT)], physiology (confirmed through compression testing, Young's modulus and stress versus strain output) and histology (verified through hematoxylin-eosin, Alizarin Red S, von-Kossa and Masson-trichrome staining) of PTER-ITC-treated GIOP female Wistar rats were assuaged. Osteoporotic amelioration through PTER-ITC treatment was further substantiated through serum biomarkers, like, parathyroid hormone (PTH), ALP, calcium (Ca²⁺), Procollagen type I N-terminal propeptide (P1NP), and 25-hydroxy vitamin D. In conclusion, this study identifies the molecular target of PTER-ITC in impeding osteoclastogenesis and facilitating osteogenesis to ameliorate osteoporosis.

Update on pharmacology, actions, dosimetry and regimens of oral glucocorticoids in dermatology

Glucocorticoids are arguably the most widely used and misused drug in dermatology. There have been recent updates in its mode of action which can impact on its judicious use. There is need to use the correct steroid preparation to maximize results and minimize side effects. We present an updated review on glucocorticoids focusing on its mode of action, rationale of its prescribing considerations and dosing regimens in dermatology. This is based on PubMed search with a focus on mode of actions and dosimetry with additional updates from standard drug books, databases and rheumatology books.

Comparison of mechanisms of angiostasis caused by the anti-inflammatory steroid 5α-tetrahydrocorticosterone versus conventional glucocorticoids

5α-Tetrahydrocorticosterone (5αTHB) is an effective topical anti-inflammatory agent in mouse, with less propensity to cause skin thinning and impede new blood vessel growth compared with corticosterone. Its anti-inflammatory effects were not prevented by RU38486, a glucocorticoid receptor antagonist, suggesting alternative mechanisms. The hypothesis that 5αTHB directly inhibits angiogenesis to a lesser extent than hydrocortisone was tested, focussing on glucocorticoid receptor mediated actions. New vessel growth from aortae from C57BL/6 male mice was monitored in culture, in the presence of 5αTHB, hydrocortisone (mixed glucocorticoid/mineralocorticoid receptor agonist) or the selective glucocorticoid receptor agonist dexamethasone. Transcript profiles were studied, as was the role of the glucocorticoid receptor, using the antagonist, RU38486. Ex vivo, 5αTHB suppressed vessel growth from aortic rings, but was less potent than hydrocortisone (EC50 2512 nM 5αTHB, versus 762 nM hydrocortisone). In contrast to conventional glucocorticoids, 5αTHB did not alter expression of genes related to extracellular matrix integrity or inflammatory signalling, but caused a small increase in Per1 transcript, and decreased transcript abundance of Pecam1 gene. RU38486 did not antagonise the residual effects of 5αTHB to suppress vessel growth or regulate gene expression, but modified effects of dexamethasone. 5αTHB did not alter expression of glucocorticoid-regulated genes Fkbp51 and Hsd11b1, unlike hydrocortisone and dexamethasone. In conclusion, compared with hydrocortisone, 5αTHB exhibits limited suppression of angiogenesis, at least directly in blood vessels and probably independent of the glucocorticoid receptor. Discriminating the mechanisms employed by 5αTHB may provide the basis for the development of novel safer anti-inflammatory drugs for topical use.

Polymeric dexamethasone prodrugs attenuate lupus nephritis in MRL/lpr mice with reduced glucocorticoid toxicity

Due to their potent immunosuppressive and anti-inflammatory effects, glucocorticoids (GCs) are the most widely used medications in treating lupus nephritis (LN). Long-term use of GCs, however, is associated with numerous off-target adverse effects. To reduce GCs' adverse effects, we previously developed two polymeric dexamethasone prodrug nanomedicines: N-(2-hydroxypropyl) methacrylamide (HPMA) copolymer-based dexamethasone prodrug (P-Dex), and micelle-forming polyethylene glycol (PEG)-based dexamethasone prodrug (ZSJ-0228). Both P-Dex and ZSJ-0228 provided sustained amelioration of LN in lupus-prone NZB/W F1 mice with reduced GC-associated adverse effects. Here, we have extended our investigation to the MRL/lpr mouse model of LN. Compared to dose equivalent daily dexamethasone sodium phosphate (Dex) treatment, monthly P-Dex or ZSJ-0228 treatments were more effective in reducing proteinuria and extending the lifespan of MRL/lpr mice. Unlike the daily Dex treatment, ZSJ-0228 was not associated with measurable GC-associated adverse effects. In contrast, adrenal gland atrophy was observed in P-Dex treated mice.

Mesoporous Materials as Elements of Modern Drug Delivery Systems for Anti-Inflammatory Agents: A Review of Recent Achievements

Interest in the use of mesoporous materials as carriers of medicinal substances has been steadily increasing in the last two decades. Mesoporous carriers have application in the preparation of delivery systems for drugs from various therapeutic groups; however, their use as the carriers of anti-inflammatory agents is particularly marked. This review article, with about 170 references, summarizes the achievements in the application of mesoporous materials as the carriers of anti-inflammatory agents in recent years. This article will discuss a variety of mesoporous carriers as well as the characteristics of their porous structure that determine further use of these materials in the field of medical applications. Special attention will be paid to the progress observed in the construction of stimuli-responsive drug carriers and systems providing site-specific drug delivery. Subsequently, a review of the literature devoted to the use of mesoporous matrices as the carriers of anti-inflammatory drugs was carried out.

Innate Immunity in Calcinosis Cutis

Calcinosis cutis is the deposition of calcium salts in the skin and subcutaneous tissue, manifesting as variably shaped papules, nodules, and plaques that can substantially impair quality of life. The pathophysiology of calcinosis cutis involves dysregulation of proinflammatory cytokines, leukocytes, and other components of the innate immune system. In some conditions associated with calcinosis cutis, elevated serum calcium, phosphate, and vitamin D may also perturb innate immunity. The mechanisms by which these lead to cutaneous and subcutaneous calcification likely parallel those seen in vascular calcification. The role of aberrant innate immunity is further supported by the association between various autoantibodies with calcinosis cutis, such as anti-MDA5, anti-NXP2, anti-centromere, and anti-topoisomerase I. Treatments for calcinosis cutis remain limited and largely experimental, although mechanistically many therapies appear to focus on dampening innate immune responses. Further research is needed to better understand the innate immune pathophysiology and establish treatment options based on randomized-controlled trials.

Pharmacologic interventions for Kawasaki disease in children: A network meta-analysis of 56 randomized controlled trials

Background

Although the current consensus recommends a standard treatment of high-dose intravenous immunoglobulin with high-dose aspirin to manage Kawasaki disease (KD), the use of different adjunctive therapies remains controversial. The aim of the current network meta-analysis (NMA) was to compare the efficacy and tolerability of different existing interventions for the initial and refractory stages of KD.

Methods

An NMA of randomised controlled trials (RCTs) was conducted using the frequentist model applied after electronic searches in PubMed, Embase, ScienceDirect, ProQuest, ClinicalTrials.gov, ClinicalKey, Cochrane CENTRAL, and Web of Science. The main outcomes were reduced fever duration/diminished severity of fever subsided. The initial stage of KD was defined as the first stage to treat patients with KD; the refractory stage of KD represents KD patients who failed to respond to standard KD treatment. The cut-off points for intravenous immunoglobulin (IVIG) were low (100–400 mg), medium (1 g), and high (at least 2 g).

Findings

A total of fifty-six RCTs with 6486 participants were included. NMA demonstrated that the medium-dosage IVIG + aspirin + infliximab [mean difference=−1.76 days (95% confidence intervals (95% CIs): −3.65 to 0.13 days) compared to high-dosage IVIG + aspirin] exhibited the shortest fever duration; likewise, the medium-dosage IVIG + aspirin + infliximab [odds ratio (OR)=0.50, 95% CIs: 0.18–1.37 compared to high-dosage IVIG + aspirin] exhibited the smallest incidence of coronary artery lesion (CAL) in the initial-stage KD. In the refractory-stage KD, the high-dosage IVIG + pulse steroid therapy (OR=0.04, 95% CIs: 0.00–0.43 compared to the high-dosage IVIG only) had the best rate of decline of fever; likewise, the high-dosage IVIG + ciclosporin [OR=0.05 (95% CIs: 0.00–1.21) compared to the high-dosage IVIG only] exhibited the smallest incidence of CAL. Infliximab significantly improved resolution compared to the high-dosage IVIG only group (OR=0.20, 95%CIs: 0.07–0.62) in refractory-stage KD.

Interpretation

The NMA demonstrated that the combination therapy with the standard therapy of IVIG and aspirin might have an additional effect on shortening the duration of fever and lowering the CAL incidence rate in patients with acute KD. Moreover, the combination therapy with high-dose IVIG and pulse steroid therapy or cyclosporine therapy might have an additional effect on improving the rate of decline of fever and lowering the incidence rate of CAL in children with refractory KD. Because some of the findings of this NMA should be considered hypothesis-generating rather than confirmatory, further evidence from de novo randomised trials is needed to support our results.

Funding

None.

An updated overview of recent advances, challenges, and clinical considerations of IL-6 signaling blockade in severe coronavirus disease 2019 (COVID-19)

Since 2019, COVID-19 has become the most important health dilemma around the world. The dysregulated immune response which results in ARDS and cytokine storm has an outstanding role in the progression of pulmonary damage in COVID-19. IL-6, through induction of pro-inflammatory chemokines and cytokines, is the pioneer of the hyperinflammatory condition and cytokine storm in severe COVID-19. Therefore, IL-6 pathway blockade is considered an emerging approach with high efficacy to reduce lung damage in COVID-19. This article aims to review the pleiotropic roles of the IL-6 pathway in lung damage and ARDS in severe COVID-19, and the rationale for IL-6 signaling blockade at different levels, including IL-6 soluble and membrane receptor pathways, IL-6 downstream signaling (such as JAK-STAT) inhibition, and non-specific anti-inflammatory therapeutic approaches. Recent clinical data of each method, with specific concentration on tocilizumab, along with other new drugs, such as sarilumab and siltuximab, have been discussed. Challenges of IL-6 signaling inhibition, such as the risk of superinfection and hepatic injury, and possible solutions have also been explained. Moreover, to achieve the highest efficacy, ongoing clinical trials and special clinical considerations of using different IL-6 inhibitors have been discussed in detail. Special considerations, including the appropriate timing and dosage, monotherapy or combination therapy, and proper side effect managment must be noticed regarding the clinical administration of these drugs. Future studies are still necessary to improve the productivity and unknown aspects of IL-6 signaling blockade for personalized treatment of severe COVID-19.

The long winding road to the safer glucocorticoid receptor (GR) targeting therapies

Glucocorticoids (Gcs) are widely used to treat inflammatory diseases and hematological malignancies, and despite the introduction of novel anti-inflammatory and anti-cancer biologics, the use of inexpensive and effective Gcs is expected to grow. Unfortunately, chronic treatment with Gcs results in multiple atrophic and metabolic side effects. Thus, the search for safer glucocorticoid receptor (GR)-targeted therapies that preserve therapeutic potential of Gcs but result in fewer adverse effects remains highly relevant. Development of selective GR agonists/modulators (SEGRAM) with reduced side effects, based on the concept of dissociation of GR transactivation and transrepression functions, resulted in limited success, and currently focus has shifted towards partial GR agonists. Additional approach is the identification and inhibition of genes associated with Gcs specific side effects. Others and we recently identified GR target genes REDD1 and FKBP51 as key mediators of Gcs-induced atrophy, and selected and validated candidate molecules for REDD1 blockage including PI3K/Akt/mTOR inhibitors. In this review, we summarized classic and contemporary approaches to safer GR-mediated therapies including unique concept of Gcs combination with REDD1 inhibitors. We discussed protective effects of REDD1 inhibitors against Gcs–induced atrophy in skin and bone and underlined the translational potential of this combination for further development of safer and effective Gcs-based therapies.

Effect of Corticosteroids on Peptide Transporter 2 Function and Induction of Innate Immune Response by Bacterial Peptides in Alveolar Epithelial Cells

In the lung alveolar region, the innate immune system serves as an important host defense system. We recently reported that peptide transporter 2 (PEPT2) has an essential role in the uptake of bacterial peptides and induction of innate immune response in alveolar epithelial cells. In this study, we aimed to clarify the effects of corticosteroids on PEPT2 function and PEPT2-dependent innate immune response. NCI-H441 (H441) cells were used as an in vitro model of human alveolar type II epithelial cells, and the effects of dexamethasone (DEX) and budesonide (BUD) on the transport function of PEPT2 and the innate immune response induced by bacterial peptides were examined. PEPT2 function, estimated by measuring β-alanyl-Nε-(7-amino-4-methyl-2-oxo-2H-1-benzopyran-3-acetyl)-L-lysine (β-Ala-Lys-AMCA) uptake in H441 cells, was suppressed by treatment with DEX and BUD in a concentration- and time-dependent manner. The suppression of PEPT2 function was partially recovered by a glucocorticoid receptor antagonist. The expression of PEPT2 and nucleotide-binding oligomerization domain 1 (NOD1) mRNAs was suppressed by treatment with DEX and BUD, while PEPT2 protein level was not changed by these treatment conditions. Additionally, the increased mRNA expression of interleukin (IL)-8 and the increased secretion of IL-8 into the culture medium induced by bacterial peptides were also suppressed by treatment with these corticosteroids. Taken together, these results clearly suggest that corticosteroids suppress PEPT2 function and bacterial peptide-induced innate immune response in alveolar epithelial cells. Therefore, PEPT2- and NOD1-dependent innate immune response induced by bacterial peptides in the lung alveolar region may be suppressed during the inhaled corticosteroid therapy.

Free Drug Theory - No Longer Just a Hypothesis?

The Free Drug Hypothesis is a well-established concept within the scientific lexicon pervading many areas of Drug Discovery and Development, and yet it is poorly defined by virtue of many variations appearing in the literature. Clearly, unbound drug is in dynamic equilibrium with respect to absorption, distribution, metabolism, elimination, and indeed, interaction with the desired pharmacological target. Binding interactions be they specific (e.g. high affinity) or nonspecific (e.g. lower affinity/higher capacity) are governed by the same fundamental physicochemical tenets including Hill-Langmuir Isotherms, the Law of Mass Action and Drug Receptor Theory. With this in mind, it is time to recognise a more coherent version and consider it the Free Drug Theory and a hypothesis no longer. Today, we have the experimental and modelling capabilities, pharmacological knowledge, and an improved understanding of unbound drug distribution (e.g. Kp_uu) to raise the bar on our understanding and analysis of experimental data. The burden of proof should be to rule out mechanistic possibilities and/or experimental error before jumping to the conclusion that any observations contradict these fundamentals.

The link module of human TSG-6 (Link_TSG6) promotes wound healing, suppresses inflammation and improves glandular function in mouse models of Dry Eye Disease

PURPOSE

To investigate the potential of the Link_TSG6 polypeptide comprising the Link module of human TSG-6 (TNF-stimulated gene/protein-6) as a novel treatment for dry eye disease (DED).

METHODS

We analyzed the therapeutic effects of topical application of Link_TSG6 in two murine models of DED, the NOD.B10.H2^b mouse model and the desiccating stress model. The effects of Link_TSG6 on the ocular surface and DED were compared with those of full-length TSG-6 (FL_TSG6) and of 0.05% cyclosporine (Restasis®). Additionally, the direct effect of Link_TSG6 on wound healing of the corneal epithelium was evaluated in a mouse model of corneal epithelial debridement.

RESULTS

Topical Link_TSG6 administration dose-dependently reduced corneal epithelial defects in DED mice while increasing tear production and conjunctival goblet cell density. At the highest dose, no corneal lesions remained in ∼50% of eyes treated. Also, Link_TSG6 significantly suppressed the levels of inflammatory cytokines at the ocular surface and inhibited the infiltration of T cells in the lacrimal glands and draining lymph nodes. Link_TSG6 was more effective in decreasing corneal epithelial defects than an equimolar concentration of FL_TSG6. Link_TSG6 was significantly more potent than Restasis® at ameliorating clinical signs and reducing inflammation. Link_TSG6 markedly and rapidly facilitated epithelial healing in mice with corneal epithelial debridement wounds.

CONCLUSION

Link_TSG6 holds promise as a novel therapeutic agent for DED through its effects on the promotion of corneal epithelial healing and tear secretion, the preservation of conjunctival goblet cells and the suppression of inflammation.

Biochemical and morphological attributes of broiler kidney in response to dietary glucocorticoid, dexamethasone

Glucocorticoids (GCs) initiate oxidative stress and cause renal damage which lead to hypertension, heart failure and ultimately death. The current study aimed to investigate the alterations in serum biochemical parameters i.e. HDL and LDL; gross anatomy, histomorphology and histomorphometry of broiler kidney in response to dietary GC, dexamethasone (DEX). Day old chicks (DOCs) were randomly assigned into four groups: control and three treatment groups (T1, T2 and T3). The control group was fed commercial broiler type ration and the treated groups were fed commercial broiler type ration containing GC (Dexamethasone @ 3, 5 and 7 mg/kg in T1, T2 and T3 group respectively). To measure the biochemical parameters, blood samples were collected on days 7, 14, 21, and 28 of the experiment. For histological investigation, kidney (left) samples were collected from the individual birds after sacrificing on days 7, 14, 21, and 28 of the experiment. Histomorphological alterations of the kidney were assessed by routine hematoxylin and eosin (H&E) staining. Biochemical analysis showed significantly increased serum HDL and LDL level compared to the control. In gross study, dark congested kidney was found with significantly decreased weight, length and width. Treatment with DEX augmented congestion, inflammation and fibrosis in kidney, as evidence by histomorphometric study. Extensively degenerated and atrophied glomeruli, degenerated tubular epithelium with distorted tubules and inter tubular empty spaces were seen. Percentage of atrophied glomeruli increased significantly and maximum percentage of glomerular atrophy was seen at day 28. These changes were found more explicitly in the higher dose group. Histomorphometric study also revealed significant decrease in the diameter of glomerulus. The findings of this study suggest that DEX may alter the serum biochemical parameters as well as kidney gross and histomorphology.

Glucocorticoid production in the thymus and brain: Immunosteroids and neurosteroids

Glucocorticoids (GCs) regulate a myriad of physiological systems, such as the immune and nervous systems. Systemic GC levels in blood are often measured as an indicator of local GC levels in target organs. However, several extra-adrenal organs can produce and metabolize GCs locally. More sensitive and specific methods for GC analysis (i.e., mass spectrometry) allow measurement of local GC levels in small tissue samples with low GC concentrations. Consequently, is it now apparent that systemic GC levels often do not reflect local GC levels. Here, we review the use of systemic GC measurements in clinical and research settings, discuss instances where systemic GC levels do not reflect local GC levels, and present evidence that local GC levels provide useful insights, with a focus on local GC production in the thymus (immunosteroids) and brain (neurosteroids). Lastly, we suggest key areas for further research, such as the roles of immunosteroids and neurosteroids in neonatal programming and the potential clinical relevance of local GC modulators.

Glucocorticoid receptor-mediated alleviation of inflammation by berberine: in vitro, in silico and in vivo investigations

As a natural dietary ingredient, berberine possesses multiple biological activities including anti-inflammatory effects. In this work, glucocorticoid receptor (GR)-mediated alleviation of inflammation by berberine was investigated by a combination of in vitro, in silico, and in vivo approaches. The fluorescence polarization assay showed that berberine bound to GR with an IC₅₀ value of 9.14 ± 0.16 pM. Molecular docking and molecular dynamics simulation suggested that berberine bound stably to the active site of GR via hydrogen bonding and hydrophobic interactions. Berberine induced GR nuclear translocation but did not activate the glucocorticoid response element in HeLa cells. Furthermore, both gene and protein expressions of PEPCK were significantly attenuated by berberine in HepG2 cells. Interestingly, berberine downregulated CBG mRNA and protein levels without up-regulating TAT mRNA and protein levels in HepG2 cells, demonstrating its dissociated characteristics that could separate transrepression from transactivation. In addition, the in vitro and in vivo anti-inflammatory effects of berberine were confirmed in lipopolysaccharide-induced RAW 264.7 cells and in a mouse model of allergic contact dermatitis, respectively. In conclusion, berberine might serve as a potential selective GR modulator.

Effects of acute low temperature stress on the hormones and gene expression of glucocorticoid receptor of large yellow croaker Larimichthys crocea

The neuroendocrine system of fish responds to low temperature via regulating hormones. To explore the adaptability of Larimichthys crocea to low temperature, the levels of the plasma cortisol, thyroid stimulating hormone (TSH), triiodothyronine (T3), thyroxine (T4), total cholesterol (TC), and glucose were determined after exposure to low temperature and during subsequent rewarming. Furthermore, the mRNA expression of the glucocorticoid receptor (GR) gene was analyzed under the stress. We found that the levels of the plasma cortisol, TSH, T3, glucose, and TC increased under the low temperature stress, suggesting that elevated hormones may be conducive to promoting the mobilization of the glucose and lipid in L. crocea exposed to low temperature. During the rewarming period, the plasma cortisol level decreased, whereas the T3 level was still significantly higher than that in the control group. Notably, the plasma T4 level was unaffected by the temperature changes. Furthermore, the sequence alignment and phylogenetic tree analysis revealed that the GR protein of L. crocea had high homology and a similar protein structure with those from other teleosts. Under the low temperature stress, the GR mRNA expression increased in the brain and head kidney, whereas it basically returned to the control level following rewarming. These findings revealed the changes of the hormones and the potential function of the GR gene in L. crocea following exposure to low temperature, providing some insights into breeding low temperature-resistant varieties of L. crocea.

Inflammatory bowel disease and psoriasis: modernizing the multidisciplinary approach

Psoriasis and inflammatory bowel disease (IBD) are immune-mediated diseases occurring in barrier organs whose main task is to protect the organism from attack. These disorders are highly prevalent especially in northern Europe where psoriasis has a prevalence of around 3-4% and IBD around 0.3%. The prevalence of IBD in North America has been estimated at around 0.4%. The total incidence rates in northern Europe have been estimated at around 6 for Crohn's disease and 11 for ulcerative colitis per 100 000 person-years, compared with an incidence rate of around 280 per 100 000 person-years for psoriasis. Both diseases are less common in countries with a lower index of development. The rise in IBD appears to occur as populations adopt a westernized lifestyle, whereas psoriasis seems more stable and prevalence differences may derive more from variation in genetic susceptibility. The gut microbiota is clearly an important driver of IBD pathogenesis; in psoriasis, changes in gut and skin microbiota have been reported, but it is less clear whether and how these changes contribute to the pathogenesis. Large studies show that most identified genes are involved in the immune system. However, psoriasis and IBD are highly heterogeneous diseases and there is a need for more precise and deeper phenotyping to identify specific subgroups and their genetic, epigenetic and molecular signatures. Epigenetic modifications of DNA such as histone modifications, noncoding RNA effects on transcription and translation and DNA methylation are increasingly recognized as the mechanism underpinning much of the gene-environment interaction in the pathogenesis of both IBD and psoriasis. Our understanding of underlying pathogenetic mechanisms has deepened fundamentally over the past decades developing hand in hand with novel therapies targeting pathways and proinflammatory cytokines incriminated in disease. There is not only substantial overlap between psoriasis and IBD, but also there are differences with implication for therapy. In psoriasis, drugs targeting interleukin-23 and interleukin-17 have shown superior efficacy compared with anti-TNFs, whilst in IBD, drugs targeting interleukin-17 may be less beneficial. The therapeutic toolbox for psoriasis is impressive and is enlarging also for IBD. Still, there are unmet needs reflecting the heterogeneity of both diseases and there is a need for closer molecular diagnostics to allow for the development of precise therapeutics.

Focus on Autoimmune Myocarditis in Graves' Disease: A Case-Based Review

The manifestations of hyperthyroidism-related myocardial damage are multitudinous, including arrhythmia, dilated cardiomyopathy, valvular diseases, and even cardiogenic shock. Acute myocarditis induced by thyrotoxicosis had been reported in a few studies. However, attention on its prevalence and underlying mechanisms is sorely lacking. Its long-term harm is often ignored, and it may eventually develop into dilated cardiomyopathy and heart failure. We report a case of Graves' disease with a progressive elevation of hypersensitive cardiac troponin-I at several days after discontinuation of the patient's anti-thyroid drugs. Cardiac magnetic resonance imaging (CMRI) showed inflammatory edema of some cardiomyocytes (stranded enhanced signals under T2 mapping), myocardial necrosis (scattered enhanced signals under T1 late gadolinium enhancement) in the medial and inferior epicardial wall, with a decreased left ventricular systolic function (48%), which implied a possibility of acute myocarditis induced by thyrotoxicosis. The patient was then given a transient glucocorticoid (GC) treatment and achieved a good curative effect. Inspired by this case, we aim to systematically elaborate the pathogenesis, diagnosis, and treatment of hyperthyroidism-induced autoimmune myocarditis. Additionally, we emphasize the importance of CMRI and GC therapy in the diagnosis and treatment of hyperthyroidism-related myocarditis.

A guide to changing paradigms of glucocorticoid receptor function-a model system for genome regulation and physiology

The glucocorticoid receptor (GR) is a bona fide ligand-regulated transcription factor. Cloned in the 80s, the GR has become one of the best-studied and clinically most relevant members of the nuclear receptor superfamily. Cooperative activity of GR with other transcription factors and a plethora of coregulators contribute to the tissue- and context-specific response toward the endogenous and pharmacological glucocorticoids (GCs). Furthermore, nontranscriptional activities in the cytoplasm are emerging as an additional function of GR. Over the past 40 years, the concepts of GR mechanisms of action had been constantly changing. Different methodologies in the pregenomic and genomic era of molecular biological research and recent cutting-edge technology in single-cell and single-molecule analysis are steadily evolving the views, how the GR in particular and transcriptional regulation in general act in physiological and pathological processes. In addition to the development of technologies for GR analysis, the use of model organisms provides insights how the GR in vivo executes GC action in tissue homeostasis, inflammation, and energy metabolism. The model organisms, namely the mouse, but also rats, zebrafish, and recently fruit flies carrying mutations of the GR became a major driving force to analyze the molecular function of GR in disease models. This guide provides an overview of the exciting research and paradigm shifts in the GR field from past to present with a focus on GR transcription factor networks, GR DNA-binding and single-cell analysis, and model systems.

Betel leaf extract and its major component hydroxychavicol promote osteogenesis and alleviate glucocorticoid-induced osteoporosis in rats

Piper betle leaves possess several ethnomedicinal properties and are immensely used in traditional medicinal practices in regions of Asian and African subcontinents. However, their effects in treating skeletal complications are least known. In this study, we evaluated cellular and molecular effects of betel leaf extract (BLE) and its major phytoconstituent, hydroxychavicol (HCV) in promoting osteogenesis in vitro and alleviating glucocorticoid induced osteoporosis (GIO) in vivo. Both BLE and HCV markedly stimulated osteoblast differentiation of C3H10T1/2 cells with increased expression of RUNX2 and osteopontin through the GSK-3β/β-catenin-signaling pathway. Also, oral administration of BLE and HCV in GIO rats resulted in restoration of bone mass and tissue microarchitecture. Thus, with our findings we conclude that BLE and HCV promote osteogenesis of C3H10T1/2 cells via the GSK-3β/β-catenin pathway and alleviate GIO in rats.

Structural Transformative Antioxidants for Dual-Responsive Anti-Inflammatory Delivery and Photoacoustic Inflammation Imaging

We have synthesized a PEGylated, phenylboronic acid modified L-DOPA pro-antioxidant (pPAD) that can self-assemble into nanoparticles (pPADN) for the loading of a model glucocorticoid dexamethasone (Dex) through 1,3-diol/phenylboronic acid chemistry and hydrophobic interactions for more effective treatment of inflammation. Upon exposure to ROS, pPADN convert into the active form of L-DOPA, and a cascade of oxidative reactions transform it into antioxidative melanin-like materials. Concomitantly, the structural transformation of pPADN triggers the specific release of Dex, along with the acidic pH of inflammatory tissue. In a rat model of osteoarthritis, Dex-loaded pPADN markedly mitigate synovial inflammation, suppress joint destruction and cartilage matrix degradation, with negligible in vivo toxicity. Moreover, in situ structural transformation makes pPADN suitable for noninvasive monitoring of therapeutic effects as a photoacoustic imaging contrast agent.

Mutant glucocorticoid receptor binding elements on the interleukin-6 promoter regulate dexamethasone effects

Background

Glucocorticoids (GCs) have been extensively used as essential modulators in clinical infectious and inflammatory diseases. The GC receptor (GR) is a transcription factor belonging to the nuclear receptor family that regulates anti-inflammatory processes and releases pro-inflammatory cytokines, such as interleukin (IL)-6.

Results

Five putative GR binding sites and other transcriptional factor binding sites were identified on theIL-6 promoter, and dexamethasone (DEX) was noted to reduce the lipopolysaccharide (LPS)-induced IL-6 production. Among mutant transcriptional factor binding sites, nuclear factor-kappa B (NF-κB), activator protein (AP)-1, and specificity protein (Sp)1–2 sites reduced basal and LPS-induced IL-6 promoter activities through various responses. The second GR binding site (GR2) was noted to play a crucial role in both basal and inducible promoter activities in LPS-induced inflammation.

Conclusions

We concluded that selective GR2 modulator might exert agonistic and antagonistic effects and could activate crucial signaling pathways during the LPS-stimulated inflammatory process.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12865-021-00413-z.

Invited review: The role of the blood-milk barrier and its manipulation for the efficacy of the mammary immune response and milk production

The intact blood-milk barrier (BMB) prevents an uncontrolled exchange of soluble and cellular components between blood and milk in the mammary gland. It enables the sustainability of the optimal milk composition for the nourishment of the offspring. Endothelial cells, connective tissue, the basal membrane, and mainly the epithelial cells provide the semipermeability of this barrier, allowing only a selective transfer of components necessary for milk production. The epithelial cells are closely connected to each other by different formations, in which the tight junctions are the most critical for separating the milk-containing compartments from the surrounding extracellular fluid and vasculature. During mastitis, the integrity of the BMB is reduced. This facilitates the transfer of immune cells and immune factors such as antibodies from blood into milk. Simultaneously, the transfer of soluble blood constituents without an obvious immune function into milk is promoted. Furthermore, a reduced BMB integrity causes a loss of milk constituents into the blood circulation. Different mechanisms are responsible for the barrier impairment including tight junction opening, but also cell degradation. To promote the cure of mastitis, the targeted manipulation of the BMB permeability may be a tool to optimize the immune function of the mammary gland. An intensified opening of the BMB supports the antibody transfer from blood into milk, which is supposed to increase the contribution of the specific immune system in the immune defense. On the contrary, a fast closure of the BMB during the recovery from mastitis can accelerate the normalization of milk composition and milk yield. Various agents have been experimentally shown to either open (e.g., pathogens and pathogen-associated molecular patterns, several nonsteroidal anti-inflammatory drugs, oxytocin, calcium chelators) or close (e.g., glucocorticoids, nonsteroidal anti-inflammatory drugs, natural anti-inflammatory drugs) the BMB.

Combination of Pulse Steroid with Intratympanic Injections in Sudden Sensorineural Hearing Loss

Introduction

Oral prednisolone was suggested as the first step to treat idiopathic sudden sensorineural hearing loss (ISSHL). This study aimed to investigate the effect of pulse therapy with methylprednisolone and intratympanic methylprednisolone, compared to traditional oral prednisolone therapy on patients with ISSHL.

Material and Methods

This randomized control trial included an experimental group receiving 500 mg intravenous methylprednisolone for three sequential days, followed by 1 mg/kg oral prednisolone for 11 days, and intratympanic Depo-Medrol four times twice a week. On the other hand, the control group received 1 mg/kg oral prednisolone for 14 days. Hearing change was assessed through pure tone audiometry. Subsequently, hearing recovery was investigated and analyzed in this study.

Result

This study was conducted on 51 patients who were divided into two groups of experimental (n=26) and control (n=25). The result revealed no significant difference between the two groups in terms of hearing improvement (P=0.28).

Conclusion

This revealed no added benefit in pulse steroids combined with intratympanic injections in cases with sudden hearing loss.

Inhaled corticosteroids and risk of lung cancer: A systematic review and meta-analysis

INTRODUCTION

Current studies investigating the association between inhaled corticosteroid (ICS) use and risk of lung cancer have yielded inconsistent findings. The aim of this systematic review and meta-analysis was to pool all currently available data to estimate this association.

METHODS

We systematically searched MEDLINE (1946 to July 2020), EMBASE (1974 to July 2020) and the Cochrane Library (June 2020) via Ovid to identify relevant articles investigating the association between the ICS use and the risk of lung cancer. Random-effects analysis was used to calculate pooled relative risks (RRs) with 95% confidence intervals (CIs).

RESULTS

Ten articles including 234 920 patients were analysed. ICS use was identified to have a decreased risk of lung cancer in chronic obstructive pulmonary disease (8 studies, 1806 patients; RR = 0.73, 95% CI: 0.61-0.87, P < .01; I²  = 60.0 %), asthma (1 study, 41 438 patients; RR = 0.44, 95% CI: 0.34-0.57, P < .01) and mixed (1 study, 46 225 patients; RR = 0.79, 95% CI: 0.69-0.90, P < .01) patients. The findings of reduced risk of lung cancer were consistent in all subgroup analyses except for the short-term follow-up (≤5 years) (RR = 0.94, 95% CI: 0.81-1.07, P = .34) and free of immortal time bias (RR = 0.94, 95% CI: 0.82-1.08, P = .38) subgroups.

CONCLUSIONS

The present study suggested that ICS use was associated with decreased risk of lung cancer. However, our findings should be interpreted with caution because most original studies were judged to be at high risk of immortal time bias.

Anthropometrics and Metabolic Syndrome in Relation to Glucocorticoid Receptor Polymorphisms in Corticosteroid Users

INTRODUCTION

Corticosteroids are widely prescribed and their use has been linked to adverse cardiometabolic outcomes. A pivotal role in the action of corticosteroids is reserved for the glucocorticoid receptor (GR). Here, we assessed the relationship of glucocorticoid sensitivity-altering GR polymorphisms with anthropometrics and metabolic syndrome (MetS) in corticosteroid users.

METHODS

In this population-based cohort study (Lifelines), we genotyped 10,621 adult participants for GR hypersensitive (1/2 copies BclI and/or N363S) and GR resistant (1/2 copies ER22/23EK and/or 9β) variants. We assessed the relationship between functional GR polymorphisms with BMI, waist circumference (WC), and MetS in users of corticosteroids.

RESULTS

Overall corticosteroid use was associated with a significantly higher BMI and WC in GR wild-type (WT) users (BMI, +0.63 kg/m2 [0.09-1.16], p = 0.022; WC, +2.03 cm [0.61-3.44], p = 0.005) and GR hypersensitive (BMI, +0.66 kg/m2 [95% CI, 0.31-1.01]; WC, +2.06 cm [1.13-2.98], both p < 0.001) but not in GR resistant users. Significantly higher WC in GR resistant carriers was observed only for inhaled corticosteroid users. With respect to MetS, again only GR WT users (odds ratio [OR] 1.44 [1.07-1.94], p = 0.017) and GR hypersensitives (OR 1.23 [95% CI, 1.00-1.50], p = 0.046) were more likely to have MetS; even more pronounced in only inhaled corticosteroid users (GR WT users, OR 1.64 [1.06-2.55], p = 0.027; GR hypersensitive users, OR 1.43 [1.08-1.91], p = 0.013).

CONCLUSIONS

Polymorphisms associated with increased GR sensitivity and WT GR are related to increased BMI, WC, and an increased MetS presence in corticosteroid users, especially of the inhaled types, when compared to nonusers. The adverse effects of corticosteroid use are less pronounced in users harboring GR resistant polymorphisms.