Unraveling the functions of the membrane-bound glucocorticoid receptors: first clues on origin and functional activity

Methylprednisolone Pulses and Prolonged Remission in Systemic Lupus Erythematosus: A Propensity Score Analysis of the Longitudinal Lupus-Cruces-Bordeaux Inception Cohort

OBJECTIVE

The objective of this study was to analyze the effect of methylprednisolone pulses (MP), given during the first year after the diagnosis of systemic lupus erythematosus (SLE), in achieving prolonged remission according to the degree of lupus activity at presentation.

METHODS

We conducted an observational study of routine clinical care data from the Lupus-Cruces-Bordeaux cohort. The end point was prolonged remission (ie, during five consecutive yearly visits). The effect of MP on remission during the first year was analyzed in the whole cohort and according to the baseline Systemic Lupus Erythematosus Disease Activity Index 2000 score: <6, 6 to 12, and >12, reflecting mild, moderate, and severe activity, respectively. For adjustment, logistic regression with propensity score (PS) and other therapeutic covariates was performed.

RESULTS

Two hundred thirty-three patients were included. Prolonged remission was achieved by 132 patients (57%). MP were associated with prolonged remission (PS-adjusted odds ratio [OR] 2.50, 95% confidence interval [CI] 1.04-623, P = 0.042). A strong clinical effect was seen among patients with moderate (adjusted OR 5.28, 95% CI 1.27-21.97, P = 0.022) and moderate-severe SLE activity (adjusted OR 4.07, 95% CI 1.11-14.82, P = 0.033). The administration of MP resulted in reduced average dosages of prednisone during the first year among patient with moderate (mean 6.6 vs 10.2 mg/day, P = 0.017) and severe activity (mean 14 vs 28 mg/day, P = 0.015). The odds of prolonged remission were increased by longer-term use of hydroxychloroquine (HCQ) and decreased by higher initial doses of prednisone.

CONCLUSION

This study supports the use of MP to induce prolonged remission in patients with SLE, particularly in those with moderate and severe activity. The extended use of HCQ also contributes to achieve prolonged remission.

Intermittent pulses of methylprednisolone with low-dose prednisone attenuate lupus symptoms in B6.MRL-Faslpr/J mice with fewer glucocorticoid side effects

Glucocorticoids (GCs) are potent anti-inflammatory and immunosuppressant medications and remain the cornerstone of systemic lupus erythematosus (SLE) therapy. However, ongoing exposure to GCs has the potential to elicit multiple adverse effects. Considering the irreplaceability of GCs in SLE therapy, it is important to explore the optimal regimen of GCs. Here, we compared the long-term efficacy and safety of pulsed and oral GC therapy in a lupus-prone mouse model. Mice were grouped using a randomized block design. We monitored survival rates, proteinuria, serum autoantibodies, and complement 3 (C3) levels up to 28 weeks of age, and assessed renal damage, bone quality, lipid deposition in the liver and marrow, glucose metabolic parameters, and levels of hormones of the hypothalamic-pituitary-adrenal (HPA) axis. Finally, we explored the mechanisms underlying the superior efficacy of the pulse regimen over oral prednisone regimen. We found that both GC regimens alleviated the poor survival rate, proteinuria, and glomerulonephritis, while also reducing serum autoantibodies and increasing the level of C3. The pulsed GC regimen showed less resistance to insulin, less suppression of the HPA axis, less bone loss, and less bone marrow fat deposition than the oral GC regimen. Additionally, GC-induced leucine zipper (GILZ) was significantly overexpressed in the GC pulse group. These results suggest that the GC pulse regimen ameliorated symptoms in lupus-prone mice, with fewer side effects, which may be related to GILZ overexpression. Our findings offer a potentially promising GC treatment option for SLE.

Non-genomic actions of steroid hormones on the contractility of non-vascular smooth muscles

Steroid hormones play an important role in physiological processes. The classical pathway of steroid actions is mediated by nuclear receptors, which regulate genes to modify biological processes. Non-genomic pathways of steroid actions are also known, mediated by cell membrane-located seven transmembrane domain receptors. Sex steroids and glucocorticoids have several membrane receptors already identified to mediate their rapid actions. However, mineralocorticoids have no identified membrane receptors, although their rapid actions are also measurable. In non-vascular smooth muscles (bronchial, uterine, gastrointestinal, and urinary), the rapid actions of steroids are mediated through the modification of the intracellular Ca2+ level by various Ca-channels and the cAMP and IP3 system. The non-genomic action can be converted into a genomic one, suggesting that these distinct pathways may interconnect, resulting in convergence between them. Sex steroids mostly relax all the non-vascular smooth muscles, except androgens and progesterone, which contract colonic and urinary bladder smooth muscles, respectively. Corticosteroids also induce relaxation in bronchial and uterine tissues, but their actions on gastrointestinal and urinary bladder smooth muscles have not been investigated yet. Bile acids also contribute to the smooth muscle contractility. Although the therapeutic application of the rapid effects of steroid hormones and their analogues for smooth muscle contractility disorders seems remote, the actions and mechanism discovered so far are promising. Further research is needed to expand our knowledge in this field by using existing experience. One of the greatest challenges is to separate genomic and non-genomic effects, but model molecules are available to start this line of research.

Balancing risks and benefits in the use of hydroxychloroquine and glucocorticoids in systemic lupus erythematosus

INTRODUCTION

Hydroxychloroquine (HCQ) and glucocorticoids (GCs) constitute the oldest and more used drugs in the treatment of systemic lupus erythematosus (SLE). Despite this long experience, both are still subject to a number of uncertainties, mainly regarding the dose.

AREAS COVERED

We review the main mechanisms of action, the clinical and toxic effects of HCQ and GCs and analyze the recommendations for the use of both in guidelines published since 2018. We offer a set of recommendations based on the pharmacology, mechanisms of action and clinical evidence.

EXPERT OPINION

HCQ is the backbone therapy for SLE, and a judicious use must be accomplished, using doses that allow a good control of lupus without compromising the safety of treatments very much prolonged over the time. Stable doses of 200 mg/day seem to accomplish both conditions. GCs should be used more judiciously, with methyl-prednisolone pulses as the main therapy for inducing rapid remission and doses ≤5-2.5 mg/day be never exceeded in long-term maintenance treatments.

Systemic lupus erythematosus and glucocorticoids: A never-ending story?

Glucocorticoids (GCs) continue to be essential agents for the management of systemic lupus erythematosus, since there are no other drugs able to active remission of active disease so rapidly. However, their potential for causing irreversible damage greatly limit their use. Fortunately, some strategies may help take advantage of their huge anti-inflammatory power while limiting GC-induced side effects. This article reviews the pharmacological basis of GC action and their translation into the clinical ground. We also offer the practical approach for the use of GC in induction and maintenance therapy as well as the strategies for GC withdrawal of the respective practice of the authors. The three main basic principles are a) using methyl-prednisolone pulses to induce remission not only in severe disease; b) limiting initial doses of prednisone to ≤30 mg/d, with rapid tapering to ≤5 mg/d, which should be the dose for maintenance therapy; and c) individualizing the decision and the strategy to withdraw GCs. Long-term therapy with HCQ and the early introduction of immunosuppressive treatment would help achieve these objectives.

Steroid hormone-mediated regulation of sexual and aggressive behaviour by non-genomic signalling

Sex and aggression are well studied examples of social behaviours that are common to most animals and are mediated by an evolutionary conserved group of interconnected nuclei in the brain called the social behaviour network. Though glucocorticoids and in particular estrogen regulate these social behaviours, their effects in the brain are generally thought to be mediated by genomic signalling, a slow transcriptional regulation mediated by nuclear hormone receptors. In the last decade or so, there has been renewed interest in understanding the physiological significance of rapid, non-genomic signalling mediated by steroids. Though the identity of the membrane hormone receptors that mediate this signalling is not clearly understood and appears to be different in different cell types, such signalling contributes to physiologically relevant behaviours such as sex and aggression. In this short review, we summarise the evidence for this phenomenon in the rodent, by focusing on estrogen and to some extent, glucocorticoid signalling. The use of these signals, in relation to genomic signalling is manifold and ranges from potentiation of transcription to the possible transduction of environmental signals.

Immunoglobulin G inhibits glucocorticoid-induced osteoporosis through occupation of FcγRI

Glucocorticoid-induced osteoporosis (GIOP) is a severe and common complication of long-term usage of glucocorticoids (GCs) and lacks of efficient therapy. Here, we investigated the mechanism of anti-inflammation effect and osteoclastogenesis side effect of GCs and immunoglobulin G (IgG) treatment against GIOP. GCs inhibited SLE IgG-induced inflammation, while IgG inhibited GCs-induced osteoclastogenesis. FcγRI and glucocorticoid receptor (GR) were found directly interacted with each other. GCs and IgG could reduce the expression of FcγRI on macrophages. The deficiency of FcγRI affected osteoclastogenesis by GCs and systemic lupus erythematosus (SLE) IgG-induced inflammation. Also, IgG efficiently reduced GIOP in mice. These data showed that GCs could induce osteoporosis and inhibit IgG-induced inflammation through FcγRI while IgG efficiently suppressed osteoporosis induced by GCs through FcγRI. Hence, our findings may help in developing a feasible therapeutic strategy against osteoporosis, such as GIOP.

Childhood-onset systemic lupus erythematosus: characteristics and the prospect of glucocorticoid pulse therapy

Childhood-onset systemic lupus erythematosus (cSLE) is an autoimmune disease that results in significant damage and often needs more aggressive treatment. Compared to adult-onset SLE, cSLE has a stronger genetic background and more prevalent elevated type I Interferon expression. The management of cSLE is more challenging because the disease itself and treatment can affect physical, psychological and emotional growth and development. High dose oral glucocorticoid (GC) has become the rule for treating moderate to severe cSLE activity. However, GC-related side effects and potential toxicities are problems that cannot be ignored. Recent studies have suggested that GC pulse therapy can achieve disease remission rapidly and reduce GC-related side effects with a reduction in oral prednisone doses. This article reviews characteristics, including pathogenesis and manifestations of cSLE, and summarized the existing evidence on GC therapy, especially on GC pulse therapy in cSLE, followed by our proposal for GC therapy according to the clinical effects and pathogenesis.

Steroids in Lupus: Enemies or Allies

Glucocorticoids are the gold standard treatment for reducing immune activation and inflammation in a wide range of inflammatory and systemic autoimmune diseases. Glucocorticoids have potent and fast actions that quickly relieve some symptoms and lower mortality in some life-threatening conditions, but they also have side effects that limit the duration of treatment and the dose used. Systemic lupus erythematosus (SLE) is a systemic autoimmune disease characterized by the involvement of numerous organs and systems and the production of autoantibodies. Most current treatments include the use of corticosteroids and immunosuppressive medications. Glucocorticoids in SLE have been classically used not only to induce remission or treat an acute situation but also as maintenance therapy. During the last decades, new approaches to managing SLE have emerged, but corticosteroids continue to be part of all therapeutic regimes. There is more and more evidence about the side effects related to the use (or abuse) of steroids and their relationship with the accrual damage. In this manuscript, we try to make a critical review of the published literature about the benefit and side effects/damage that can be attributed to the use of glucocorticoids.

Pulse Methylprednisolone Versus Dexamethasone in COVID-19: A Multicenter Cohort Study

Although pulse (high-dose) methylprednisolone therapy can hypothetically control immune system flare-ups effectively, the clinical benefit of pulse methylprednisolone compared with dexamethasone in COVID-19 remains inconclusive.

Context-Dependent Role of Glucocorticoid Receptor Alpha and Beta in Breast Cancer Cell Behaviour

Background. The dual role of GCs has been observed in breast cancer; however, due to many concomitant factors, GR action in cancer biology is still ambiguous. In this study, we aimed to unravel the context-dependent action of GR in breast cancer. Methods. GR expression was characterized in multiple cohorts: (1) 24,256 breast cancer specimens on the RNA level, 220 samples on the protein level and correlated with clinicopathological data; (2) oestrogen receptor (ER)-positive and -negative cell lines were used to test for the presence of ER and ligand, and the effect of the GRβ isoform following GRα and GRβ overexpression on GR action, by in vitro functional assays. Results. We found that GR expression was higher in ER- breast cancer cells compared to ER+ ones, and GR-transactivated genes were implicated mainly in cell migration. Immunohistochemistry showed mostly cytoplasmic but heterogenous staining irrespective of ER status. GRα increased cell proliferation, viability, and the migration of ER- cells. GRβ had a similar effect on breast cancer cell viability, proliferation, and migration. However, the GRβ isoform had the opposite effect depending on the presence of ER: an increased dead cell ratio was found in ER+ breast cancer cells compared to ER- ones. Interestingly, GRα and GRβ action did not depend on the presence of the ligand, suggesting the role of the "intrinsic", ligand-independent action of GR in breast cancer. Conclusions. Staining differences using different GR antibodies may be the reason behind controversial findings in the literature regarding the expression of GR protein and clinicopathological data. Therefore, caution in the interpretation of immunohistochemistry should be applied. By dissecting the effects of GRα and GRβ, we found that the presence of the GR in the context of ER had a different effect on cancer cell behaviour, but independently of ligand availability. Additionally, GR-transactivated genes are mostly involved in cell migration, which raises GR's importance in disease progression.

What the hippocampus tells the HPA axis: Hippocampal output attenuates acute stress responses via disynaptic inhibition of CRF+ PVN neurons

The hippocampus exerts inhibitory feedback on the release of glucocorticoids. Because the major hippocampal efferent projections are excitatory, it has been hypothesized that this inhibition is mediated by populations of inhibitory neurons in the hypothalamus or elsewhere. These regions would be excited by hippocampal efferents and project to corticotropin-releasing factor (CRF) cells in the paraventricular nucleus of the hypothalamus (PVN). A direct demonstration of the synaptic responses elicited by hippocampal outputs in PVN cells or upstream GABAergic interneurons has not been provided previously. Here, we used viral vectors to express channelrhodopsin (ChR) and enhanced yellow fluorescent protein (EYFP) in pyramidal cells in the ventral hippocampus (vHip) in mice expressing tdTomato in GABA- or CRF-expressing neurons. We observed dense innervation of the bed nucleus of the stria terminalis (BNST) by labeled vHip axons and sparse labeling within the PVN. Using whole-cell voltage-clamp recording in parasagittal brain slices containing the BNST and PVN, photostimulation of vHip terminals elicited rapid excitatory postsynaptic currents (EPSCs) and longer-latency inhibitory postsynaptic currents (IPSCs) in both CRF+ and GAD + cells. The ratio of synaptic excitation and inhibition was maintained in CRF + cells during 20 Hz stimulus trains. Photostimulation of hippocampal afferents to the BNST and PVN in vivo inhibited the rise in blood glucocorticoid levels produced by acute restraint stress. We thus provide functional evidence suggesting that hippocampal output to the BNST contributes to a net inhibition of the hypothalamic-pituitary axis, providing further mechanistic insights into this process using methods with enhanced spatial and temporal resolution.

The Shifting Landscape of Lupus Nephritis Management: A Review

Systemic lupus erythematosus (SLE) is commonly the first autoimmune disease that comes to mind for most people when rheumatology is mentioned. It remains an enigma that many of us, including patients and healthcare providers, do not fully understand. Although an ancient disease, it still remains difficult to both diagnose and treat. Historically, there has always been a paucity of therapeutic interventions for SLE as a whole. One of the most distressing manifestations for the patient and diagnostic and therapeutically challenging aspects of SLE is lupus nephritis (LN). There has historically been some difficultly in the development of LN drugs that provide significant therapeutic benefits while having an acceptable side-effect profile. This difficulty led to decades in which no drugs were approved for LN. With a better understanding of the pathogenesis of SLE and LN and improvement in trial design, great therapeutic strides have recently been made. The immunosuppressive landscape of LN has changed recently with the approval of two newer agents as well as a number of promising trials in LN. With the increased number of therapeutic agents (both immunosuppressive and non-immunosuppressive), the clinical question is how and when to use these medications, and, more importantly, which agents to use first. With the increased number of agents, the answers to these questions are becoming more difficult to answer. The purpose of the paper is to review updates in LN diagnosis and management.

Mechanisms behind context-dependent role of glucocorticoids in breast cancer progression

Glucocorticoids (GCs), mostly dexamethasone (dex), are routinely administered as adjuvant therapy to manage side effects in breast cancer. However, recently, it has been revealed that dex triggers different effects and correlates with opposite outcomes depending on the breast cancer molecular subtype. This has raised new concerns regarding the generalized use of GC and suggested that the context-dependent effects of GCs can be taken into potential consideration during treatment design. Based on this, attention has recently been drawn to the role of the glucocorticoid receptor (GR) in development and progression of breast cancer. Therefore, in this comprehensive review, we aimed to summarize the different mechanisms behind different context-dependent GC actions in breast cancer by applying a multilevel examination, starting from the association of variants of the GR-encoding gene to expression at the mRNA and protein level of the receptor, and its interactions with other factors influencing GC action in breast cancer. The role of GCs in chemosensitivity and chemoresistance observed during breast cancer therapy is discussed. In addition, experiences using GC targeting therapeutic options (already used and investigated in preclinical and clinical trials), such as classic GC dexamethasone, selective glucocorticoid receptor agonists and modulators, the GC antagonist mifepristone, and GR coregulators, are also summarized. Evidence presented can aid a better understanding of the biology of context-dependent GC action that can lead to further advances in the personalized therapy of breast cancer by the evaluation of GR along with the conventional estrogen receptor (ER) and progesterone receptor (PR) in the routine diagnostic procedure.

Systemic Lupus Erythematosus Patients With Related Organic Damage Are at High Risk of Hypothyroidism

PURPOSE

The aim of this study included determining the prevalence of hypothyroidism in patients with systemic lupus erythematosus (SLE), clarifying the clinical characteristics of SLE patients with hypothyroidism, and identifying the relationship between hypothyroidism and SLE-related organic damage. Another purpose was to analyze the relationship between SLE and thyroid autoantibody. We also intended to discuss the pathogenesis of hypothyroidism in SLE patients, which would provide clues for further investigation.

METHODS

This study recruited 856 SLE patients and 856 age- and sex-matched healthy population and compared the prevalence of hypothyroidism between the cases and controls. Univariate and multivariate logistic analyses were applied to identify risk factors for hypothyroidism in SLE patients.

RESULTS

SLE patients had higher prevalence of clinical hypothyroidism (9.10%) and TgAb+TPOAb- (10.40%) than controls. The prevalence of hypothyroidism was the highest in SLE patients aged 16-26 years (18.9%) and decreased with age. The prevalence of autoimmune hypothyroidism in SLE group was higher than that in the control group (64.4% vs. 51.5%, P=0.042), which was mainly due to TgAb; the prevalence of non-autoimmune hypothyroidism in SLE group was also significantly higher than that in the control group (67.3% vs. 47.8%, P<0.001). Based on multivariate analysis, the use of glucocorticoids/immunosuppressants, liver abnormality, lupus nephritis (LN), and cardiac insufficiency were independently associated with hypothyroidism in SLE patients.

CONCLUSION

The prevalence of hypothyroidism in SLE patients was higher than that in controls and decreased with age. The results suggested that young SLE patients combined with LN, liver abnormality and cardiac insufficiency were at higher risk of hypothyroidism. According to the results of this study, we speculated that SLE might have impact on thyroid, and SLE might be one of the causes of hypothyroidism.

Sexual Dimorphism in Glucocorticoid Stress Response

Chronic stress is encountered in our everyday life and is thought to contribute to a number of diseases. Many of these stress-related disorders display a sex bias. Because glucocorticoid hormones are the main biological mediator of chronic stress, researchers have been interested in understanding the sexual dimorphism in glucocorticoid stress response to better explain the sex bias in stress-related diseases. Although not yet demonstrated for glucocorticoid regulation, sex chromosomes do influence sex-specific biology as soon as conception. Then a transient rise in testosterone start to shape the male brain during the prenatal period differently to the female brain. These organizational effects are completed just before puberty. The cerebral regions implicated in glucocorticoid regulation at rest and after stress are thereby impacted in a sex-specific manner. After puberty, the high levels of all gonadal hormones will interact with glucocorticoid hormones in specific crosstalk through their respective nuclear receptors. In addition, stress occurring early in life, in particular during the prenatal period and in adolescence will prime in the long-term glucocorticoid stress response through epigenetic mechanisms, again in a sex-specific manner. Altogether, various molecular mechanisms explain sex-specific glucocorticoid stress responses that do not exclude important gender effects in humans.

The Use of Glucocorticoids in Lupus Nephritis: New Pathways for an Old Drug

Glucocorticoids therapy has greatly improved the outcome of lupus nephritis patients. Since their discovery, their adverse effects have counterbalanced their beneficial anti-inflammatory effects. Glucocorticoids exert their effects through both genomic and non-genomic pathways. Differential activation of these pathways is clinically relevant in terms of benefit and adverse effects. Ongoing aims in lupus nephritis treatment development focus on a better use of glucocorticoids combined with immunosuppressant drugs and biologics. Newer regimens aim to decrease the peak glucocorticoid dose, allow a rapid glucocorticoid tapering, and intend to control disease activity with a lower cumulative glucocorticoid exposure. In this review we discuss the mechanisms, adverse effects and recent strategies to limit glucocorticoid exposure without compromising treatment efficacy.

Treating systemic lupus erythematosus in the 21st century: new drugs and new perspectives on old drugs

Besides treating acute flares, the management of SLE should aim at preventing organ damage accrual and drug-associated harms, improving health-related quality of life and prolonging survival. At present, therapy is based on combinations of antimalarials (mainly HCQ), considered the backbone of SLE treatment, glucocorticoids and immunosuppressive drugs. However, these regimens are not universally effective and a substantial degree of damage can be caused by exposure to glucocorticoids. In this review we provide a critical appraisal of the efficacy and safety of available treatments as well as a brief discussion of potentially novel compounds in patients with SLE. We emphasize the use of methylprednisolone pulses for moderate–severe flares, followed by low–moderate doses of oral prednisone with quick tapering to maintenance doses of ≤5 mg/day, as well as the prompt institution of immunosuppressive drugs in the setting of severe disease but also as steroid-sparing agents. Indications for the use of biologic agents, namely belimumab and rituximab, in refractory or organ-threatening disease are also presented. We conclude by proposing evidence- and experience-based treatment strategies tailored to the clinical scenario and prevailing organ involvement that can aid clinicians in managing this complex disease.

Second week methyl-prednisolone pulses improve prognosis in patients with severe coronavirus disease 2019 pneumonia: An observational comparative study using routine care data

Objective

To analyze the effects of a short course of methyl-prednisolone pulses (MP) during the second week of disease (week-2) in patients with severe coronavirus disease 2019 (COVID-19) pneumonia.

Methods

Comparative observational study using data collected from routine care at Hospital Universitario Cruces, Barakaldo, Bizkaia, Spain in patients with COVID-19 pneumonia. We compared patients who received week-2-MP (125–250 mg/d x3) with those who did not, with the end-points time to death and time to death or endotracheal intubation.

Results

We included 242 patients with COVID-19 pneumonia and elevated inflammatory markers at admission. Sixty-one patients (25%) received week-2-MP. Twenty-two patients (9%) died and 31 (12.8%) suffered death or intubation. The adjusted HRs for death and death or intubation for patients in the week-2-MP group were 0.35 (95%CI 0.11 to 1.06, p = 0.064) and 0.33 (95%CI 0.13 to 0.84, p = 0.020), respectively. These differences were specifically seen in the subcohort of patients with a SpO2/FiO2 at day 7 lower than 353 (adjusted HR 0.31, 95% CI 0.08 to 1.12, p = 0.073 and HR 0.34, 95%CI 0.12 to 0.94, p = 0.038, respectively) but not in patients with higher SpO2/FiO2. Patients receiving out-of-week-2-MP, non-pulse glucocorticoids or no glucocorticoids had an increased adjusted risk for both outcomes compared with week-2-MP group: HR 5.04 (95% CI 0.91–27.86), HR 10.09 (95% CI 2.14–47.50), HR 4.14 (95% CI 0.81–21.23), respectively, for death; HR 7.38 (95% CI 1.86–29.29), HR 13.71 (95% CI 3.76–50.07), HR 3.58 (95% CI 0.89–14.32), respectively, for death or intubation. These differences were significant only in the subgroup with low SpO2/FiO2.

Conclusions

Week-2-MP are effective in improving the prognosis of patients with COVID-19 pneumonia with features of inflammatory activity and respiratory deterioration entering the second week of disease. The recognition of this high-risk population should prompt early use of MP at this point.

Glucocorticoids in Systemic Lupus Erythematosus. Ten Questions and Some Issues

Since the discovery of glucocorticoids (GCs), their important anti-inflammatory effect, rapid mechanism of action, low cost, and accessibility have made them one of the mainstays of treatment for Systemic lupus erythematosus (SLE). Although their use has allowed controlling the disease and reducing acute mortality in severe conditions, the implementation of a scheme based on high doses for long periods has inevitably been accompanied by an increase in adverse effects and infections, including long-term damage. The objective of this review is to answer some important questions that may arise from its use in daily clinical practice, and to propose a paradigm based on the use of methylprednisolone pulses followed by medium-low doses and a rapid decrease of prednisone.

Glucocorticoid Priming of Nonviral Gene Delivery to hMSCs Increases Transfection by Reducing Induced Stresses

Human mesenchymal stem cells (hMSCs) are under study for cell and gene therapeutics because of their immunomodulatory and regenerative properties. Safe and efficient gene delivery could increase hMSC clinical potential by enabling expression of transgenes for control over factor production, behavior, and differentiation. Viral delivery is efficient but suffers from safety issues, while nonviral methods are safe but highly inefficient, especially in hMSCs. We previously demonstrated that priming cells with glucocorticoids (Gcs) before delivery of DNA complexes significantly increases hMSC transfection, which correlates with a rescue of transfection-induced metabolic and protein synthesis decline, and apoptosis. In this work, we show that transgene expression enhancement is mediated by transcriptional activation of endogenous hMSC genes by the cytosolic glucocorticoid receptor (cGR) and that transfection enhancement can be potentiated with a GR transcription-activation synergist. We demonstrate that the Gc-activated cGR modulates endogenous hMSC gene expression to ameliorate transfection-induced endoplasmic reticulum (ER) and oxidative stresses, apoptosis, and inflammatory responses to prevent hMSC metabolic and protein synthesis decline, resulting in enhanced transgene expression after nonviral gene delivery to hMSCs. These results provide insights important for rational design of more efficient nonviral gene delivery and priming techniques that could be utilized for clinical hMSC applications.

Seventy years after Hench’s Nobel prize: revisiting the use of glucocorticoids in systemic lupus erythematosus

In 1950, Hench, Kendall and Reichstein were awarded with the Nobel Prize in Physiology and Medicine for the isolation and first therapeutic use of glucocorticoids. Since then, they have become one of the main agents in the treatment of systemic lupus erythematosus (SLE). The use of high-dose oral glucocorticoids (usually 1 mg/kg/day of prednisone equivalent) have become the rule for treating moderate to severe lupus activity. In addition, tapering schemes have not been well defined, all this leading to prolonged exposures to potentially damaging amounts of glucocorticoids. Several studies have shown that glucocorticoids are a major cause of toxicity in SLE in a dose-dependent manner, with prolonged doses greater than 7.5 mg/day being associated with damage accrual. Thus, there is an urgent need for different therapeutic schedules that can achieve a rapid and durable control of lupus activity while reducing the many unwanted effects of glucocorticoids. Recent data show that pulses of methyl-prednisolone are an effective first-line therapy to treat lupus flares (not only severe ones) without major short or long-term toxicity and allowing a reduction in oral prednisone doses. Universal use of hydroxychloroquine – always recommended, infrequently accomplished – and early therapy with immunosuppressive drugs also help control SLE and reduce prednisone load. Results from observational studies confirm the more rapid achievement of remission and the reduction of long-term damage using these combination schedules with reduced prednisone doses. Seventy years after their first therapeutic use, we are learning to use glucocorticoids in a more efficient and safe manner.

Glucocorticoid Sexual Dimorphism in Metabolism: Dissecting the Role of Sex Hormones

Glucocorticoids are steroid hormones that are of pivotal importance in human physiology. Glucocorticoid signaling is complex in nature and dependent on many interacting factors. As glucocorticoids exhibit sexually dimorphic effects on several key processes including in metabolism, crosstalk with the sex steroid hormones (androgens and estrogens) is relevant. In this review, we highlight the state-of-the-art knowledge on glucocorticoid sexual dimorphism and sex hormone crosstalk. We include current insight in the molecular mechanisms that underlie nuclear steroid receptor crosstalk, and sex hormone effects on glucocorticoid metabolism. Finally, we show how these findings translate to humans exposed to excess glucocorticoid signaling, and we propose future avenues in the emerging field of steroid hormone crosstalk.

Context-Dependent Effect of Glucocorticoids on the Proliferation, Differentiation, and Apoptosis of Regulatory T Cells: A Review of the Empirical Evidence and Clinical Applications

Glucocorticoids (GCs) are widely used to treat several diseases because of their powerful anti-inflammatory and immunomodulatory effects on immune cells and non-lymphoid tissues. The effects of GCs on T cells are the most relevant in this regard. In this review, we analyze how GCs modulate the survival, maturation, and differentiation of regulatory T (Treg) cell subsets into both murine models and humans. In this way, GCs change the Treg cell number with an impact on the mid-term and long-term efficacy of GC treatment. In vitro studies suggest that the GC-dependent expansion of Treg cells is relevant when they are activated. In agreement with this observation, the GC treatment of patients with established autoimmune, allergic, or (auto)inflammatory diseases causes an expansion of Treg cells. An exception to this appears to be the local GC treatment of psoriatic lesions. Moreover, the effects on Treg number in patients with multiple sclerosis are uncertain. The effects of GCs on Treg cell number in healthy/diseased subjects treated with or exposed to allergens/antigens appear to be context-dependent. Considering the relevance of this effect in the maturation of the immune system (tolerogenic response to antigens), the success of vaccination (including desensitization), and the tolerance to xenografts, the findings must be considered when planning GC treatment.

Glucocorticoid signaling and osteoarthritis

Glucocorticoids are steroid hormones synthesized and released by the adrenal cortex. Their main function is to maintain cell homeostasis through a variety of signaling pathways, responding to changes in an organism's environment or developmental status. Mimicking the actions of natural glucocorticoids, synthetic glucocorticoids have been recruited to treat many diseases that implicate glucocorticoid receptor signaling such as osteoarthritis. In osteoarthritis, synthetic glucocorticoids aim to alleviate inflammation and pain. The variation of patients' response and the possibility of complications associated with their long-term use have led to a need for a better understanding of glucocorticoid receptor signaling in osteoarthritis. In this review, we performed a literature search in the molecular pathways that link the osteoarthritic joint to the glucocorticoid receptor signaling. We hope that this information will advance research in the field and propose new molecular targets for the development of more optimized therapies for osteoarthritis.

POMC: The Physiological Power of Hormone Processing

Pro-opiomelanocortin (POMC) is the archetypal polypeptide precursor of hormones and neuropeptides. In this review, we examine the variability in the individual peptides produced in different tissues and the impact of the simultaneous presence of their precursors or fragments. We also discuss the problems inherent in accurately measuring which of the precursors and their derived peptides are present in biological samples. We address how not being able to measure all the combinations of precursors and fragments quantitatively has affected our understanding of the pathophysiology associated with POMC processing. To understand how different ratios of peptides arise, we describe the role of the pro-hormone convertases (PCs) and their tissue specificities and consider the cellular processing pathways which enable regulated secretion of different peptides that play crucial roles in integrating a range of vital physiological functions. In the pituitary, correct processing of POMC peptides is essential to maintain the hypothalamic-pituitary-adrenal axis, and this processing can be disrupted in POMC-expressing tumors. In hypothalamic neurons expressing POMC, abnormalities in processing critically impact on the regulation of appetite, energy homeostasis, and body composition. More work is needed to understand whether expression of the POMC gene in a tissue equates to release of bioactive peptides. We suggest that this comprehensive view of POMC processing, with a focus on gaining a better understanding of the combination of peptides produced and their relative bioactivity, is a necessity for all involved in studying this fascinating physiological regulatory phenomenon.

Endocannabinoids: Effectors of glucocorticoid signaling

For decades, there has been speculation regarding the interaction of cannabinoids with glucocorticoid systems. Given the functional redundancy between many of the physiological effects of glucocorticoids and cannabinoids, it was originally speculated that the biological mechanisms of cannabinoids were mediated by direct interactions with glucocorticoid systems. With the discovery of the endocannabinoid system, additional research demonstrated that it was actually the opposite; glucocorticoids recruit endocannabinoid signaling, and that the engagement of endocannabinoid signaling mediated many of the neurobiological and physiological effects of glucocorticoids. With the development of advances in pharmacology and genetics, significant advances in this area have been made, and it is now clear that functional interactions between these systems are critical for a wide array of physiological processes. The current review acts a comprehensive summary of the contemporary state of knowledge regarding the biological interactions between glucocorticoids and endocannabinoids, and their potential role in health and disease.

Transcriptomic Analysis Reveals Significant B Lymphocyte Suppression in Corticosteroid-Treated Hosts with Pneumocystis Pneumonia

Pneumocystis pneumonia (PCP) is an opportunistic, infectious disease that is prevalent in immunosuppressed hosts. Corticosteroid treatment is the most significant risk factor for patients with PCP who are human immunodeficiency virus negative, although little is known about how corticosteroids alter the host defense against Pneumocystis infection. In the present study, we used transcriptome analysis to examine the immune response in the lungs of corticosteroid-treated PCP mice. The results showed down-regulation in the genes related to both native immunity, such as antigen processing and presentation, inflammatory response, and phagocytosis, as well as B and T lymphocyte immunity. The repression of gene expression, corresponding to B cell immunity, including B cell signaling, homeostasis, and Ig production, was prominent. The finding was confirmed by quantitative PCR of mouse lungs and the peripheral blood of patients with PCP. Flow cytometry also revealed a significant depletion of B cells in corticosteroid-treated PCP mice. Our study has highlighted that corticosteroid treatment suppresses the B cell immunity in the PCP host, which is likely one of the main reasons that corticosteroid treatment may stimulate PCP development.

New Insights in Glucocorticoid Receptor Signaling-More Than Just a Ligand-Binding Receptor

The clinical use of classical glucocorticoids (GC) is narrowed by the many side effects it causes and the resistance to GC observed in some diseases. Since the great majority of GC effects depend on the activation of a glucocorticoid receptor (GR), many research groups had focused to better understand the signaling pathways involving those receptors. Transgenic animal models and genetic modifications of the receptor brought a huge insight into GR mechanisms of action. This in turn opened a new window for the search of selective GR modulators that ideally may have agonistic and antagonistic combined effects and activate one specific signaling pathway, inducing mostly transrepression or transactivation mechanisms. Another important research field concerns to posttranslational modifications that affect the GR and consequently also affect its signaling and function. In this mini review, we discuss many of those aspects of GR signaling, as well as findings like the ligand-independent activation of GR, which add another layer of complexity in GR signaling pathways. Although several recent data have been added to the GR field, much work has yet to be done, especially to find out the biological relevance of those alternative GR signaling pathways. Improving the knowledge about alternative GR signaling pathways and understanding how these pathways intercommunicate and in which situations they are relevant might help to develop new strategies to take benefit of it and to improve GC or other compounds efficacy causing minimal side effects.

Stress Signals, Mediated by Membranous Glucocorticoid Receptor, Activate PLC/PKC/GSK-3β/β-catenin Pathway to Inhibit Wound Closure

Glucocorticoids (GCs), key mediators of stress signals, are also potent wound healing inhibitors. To understand how stress signals inhibit wound healing, we investigated the role of membranous glucocorticoid receptor (mbGR) by using cell-impermeable BSA-conjugated dexamethasone. We found that mbGR inhibits keratinocyte migration and wound closure by activating a Wnt-like phospholipase (PLC)/ protein kinase C (PKC) signaling cascade. Rapid activation of mbGR/PLC/PKC further leads to activation of known biomarkers of nonhealing found in patients, β-catenin and c-myc. Conversely, a selective inhibitor of PKC, calphostin C, blocks mbGR/PKC pathway, and rescues GC-mediated inhibition of keratinocyte migration in vitro and accelerates wound epithelialization of human wounds ex vivo. This novel signaling mechanism may have a major impact on understanding how stress response via GC signaling regulates homeostasis and its role in development and treatments of skin diseases, including wound healing. To test tissue specificity of this nongenomic signaling mechanism, we tested retinal and bronchial human epithelial cells and fibroblasts. We found that mbGR/PLC/PKC signaling cascade exists in all cell types tested, suggesting a more general role. The discovery of this nongenomic signaling pathway, in which glucocorticoids activate Wnt pathway via mbGR, provides new insights into how stress-mediated signals may activate growth signals in various epithelial and mesenchymal tissues.

G6PC2 Modulates the Effects of Dexamethasone on Fasting Blood Glucose and Glucose Tolerance

The glucose-6-phosphatase catalytic subunit 2 (G6PC2) gene encodes an islet-specific glucose-6-phosphatase catalytic subunit. G6PC2 forms a substrate cycle with glucokinase that determines the glucose sensitivity of insulin secretion. Consequently, deletion of G6pc2 lowers fasting blood glucose (FBG) without affecting fasting plasma insulin. Although chronic elevation of FBG is detrimental to health, glucocorticoids induce G6PC2 expression, suggesting that G6PC2 evolved to transiently modulate FBG under conditions of glucocorticoid-related stress. We show, using competition and mutagenesis experiments, that the synthetic glucocorticoid dexamethasone (Dex) induces G6PC2 promoter activity through a mechanism involving displacement of the islet-enriched transcription factor MafA by the glucocorticoid receptor. The induction of G6PC2 promoter activity by Dex is modulated by a single nucleotide polymorphism, previously linked to altered FBG in humans, that affects FOXA2 binding. A 5-day repeated injection paradigm was used to examine the chronic effect of Dex on FBG and glucose tolerance in wild-type (WT) and G6pc2 knockout mice. Acute Dex treatment only induces G6pc2 expression in 129SvEv but not C57BL/6J mice, but this chronic treatment induced G6pc2 expression in both. In 6-hour fasted C57BL/6J WT mice, Dex treatment lowered FBG and improved glucose tolerance, with G6pc2 deletion exacerbating the decrease in FBG and enhancing the improvement in glucose tolerance. In contrast, in 24-hour fasted C57BL/6J WT mice, Dex treatment raised FBG but still improved glucose tolerance, with G6pc2 deletion limiting the increase in FBG and enhancing the improvement in glucose tolerance. These observations demonstrate that G6pc2 modulates the complex effects of Dex on both FBG and glucose tolerance.

Glucocorticoid-independent modulation of GR activity: Implications for immunotherapy

Pharmacological doses of glucocorticoids (GCs), acting via the glucocorticoid receptor (GR) to repress inflammation and immune function, remain the most effective therapy in the treatment of inflammatory and immune diseases. Since many patients on GC therapy exhibit GC resistance and severe side-effects, much research is focused on developing more selective GCs and combination therapies, with greater anti-inflammatory potency. GCs mediate their classical genomic transcriptional effects by binding to the cytoplasmic GR, followed by nuclear translocation and modulation of transcription of target genes by direct DNA binding of the GR or its tethering to other transcription factors. Recent evidence suggests, however, that the responses mediated by the GR are much more complex and involve multiple parallel mechanisms integrating simultaneous signals from other receptors, both in the absence and presence of GCs, to shift the sensitivity of a target cell to GCs. The level of cellular stress, immune activation status, or the cell cycle phase may be crucial for determining GC sensitivity and GC responsiveness as well as subcellular localization of the GR and GR levels. Central to the development of new drugs that target GR signaling alone or as add-on therapies, is an in-depth understanding of the molecular mechanisms of GC-independent GR desensitization, priming and activation of the unliganded GR, as well as synergy and cross-talk with other signaling pathways. This review will discuss the information currently available on these topics and their relevance to immunotherapy, as well as identify unanswered questions and future areas of research.

The clinical use of corticosteroids in pregnancy

BACKGROUND

The use of antenatal steroid therapy is common in pregnancy. In early pregnancy, steroids may be used in women for the treatment of recurrent miscarriage or fetal abnormalities such as congenital adrenal hyperplasia. In mid-late pregnancy, the antenatal administration of corticosteroids to expectant mothers in anticipation of preterm birth is one of the most important advances in perinatal medicine; antenatal corticosteroids are now standard care for pregnancies at risk of premature delivery in high- and middle-income countries. The widespread uptake of this therapy is due to a compelling body of evidence demonstrating improved neonatal outcomes following antenatal corticosteroid exposure, stemming most notably from corticosteroid-driven maturation of fetal pulmonary function. As we approach the 50th anniversary of landmark work in this area by Liggins and Howie, it is apparent that much remains to be understood with regards to how we might best apply antenatal corticosteroid therapy to improve pregnancy outcomes at both early and mid to late gestation.

METHODS

Drawing on advances in laboratory science, pre-clinical and clinical studies, we performed a narrative review of the scientific literature to provide a timely update on the benefits, risks and uncertainties regarding antenatal corticosteroid use in pregnancy. Three, well-established therapeutic uses of antenatal steroids, namely recurrent miscarriage, congenital adrenal hyperplasia and preterm birth, were selected to frame the review.

RESULTS

Even the most well-established antenatal steroid therapies lack the comprehensive pharmacokinetic and dose-response data necessary to optimize dosing regimens. New insights into complex, tissue-specific corticosteroid signalling by genomic-dependent and independent mechanisms have not been used to inform corticosteroid treatment strategies. There is growing evidence that some fetal corticosteroid treatments are either ineffective, or may result in adverse outcomes, in addition to lasting epigenetic changes in a variety of homeostatic mechanisms. Nowhere is the need to better understand the intricacies of corticosteroid therapy better conveyed than in the findings of Althabe and colleagues who recently reported an increase in overall neonatal mortality and maternal morbidity in association with antenatal corticosteroid administration in low-resource settings.

CONCLUSIONS

New research to clarify the benefits and potential risks of antenatal corticosteroid therapy is urgently needed, especially with regard to corticosteroid use in low-resource environments. We conclude that there is both significant scope and an urgent need for further research-informed refinement to the use of antenatal corticosteroids in pregnancy.

Glucocorticoid treatment and endocrine pancreas function: implications for glucose homeostasis, insulin resistance and diabetes

Glucocorticoids (GCs) are broadly prescribed for numerous pathological conditions because of their anti-inflammatory, antiallergic and immunosuppressive effects, among other actions. Nevertheless, GCs can produce undesired diabetogenic side effects through interactions with the regulation of glucose homeostasis. Under conditions of excess and/or long-term treatment, GCs can induce peripheral insulin resistance (IR) by impairing insulin signalling, which results in reduced glucose disposal and augmented endogenous glucose production. In addition, GCs can promote abdominal obesity, elevate plasma fatty acids and triglycerides, and suppress osteocalcin synthesis in bone tissue. In response to GC-induced peripheral IR and in an attempt to maintain normoglycaemia, pancreatic β-cells undergo several morphofunctional adaptations that result in hyperinsulinaemia. Failure of β-cells to compensate for this situation favours glucose homeostasis disruption, which can result in hyperglycaemia, particularly in susceptible individuals. GC treatment does not only alter pancreatic β-cell function but also affect them by their actions that can lead to hyperglucagonaemia, further contributing to glucose homeostasis imbalance and hyperglycaemia. In addition, the release of other islet hormones, such as somatostatin, amylin and ghrelin, is also affected by GC administration. These undesired GC actions merit further consideration for the design of improved GC therapies without diabetogenic effects. In summary, in this review, we consider the implication of GC treatment on peripheral IR, islet function and glucose homeostasis.

State of the art in the treatment of systemic vasculitides

Anti-neutrophil cytoplasm antibodies (ANCA) are associated with small vessel vasculitides (AASV) affecting the lungs and kidneys. Structured clinical assessment using the Birmingham Vasculitis Activity Score and Vasculitis Damage Index should form the basis of a treatment plan and be used to document progress, including relapse. Severe disease with organ or life threatening manifestations needs cyclophosphamide or rituximab, plus high dose glucocorticoids, followed by lower dose steroid plus azathioprine, or methotrexate. Additional plasmapheresis is effective for very severe disease, reducing dialysis dependence from 60 to 40% in the first year, but with no effect on mortality or long-term renal function, probably due to established renal damage. In milder forms of ANCA-associated vasculitis, methotrexate, leflunomide, or mycophenolate mofetil are effective. Mortality depends on initial severity: 25% in patients with renal failure or severe lung hemorrhage; 6% for generalized non-life threatening AASV but rising to 30–40% at 5 years. Mortality from GPA is four times higher than the background population. Early deaths are due to active vasculitis and infection. Subsequent deaths are more often due to cardiovascular events, infection, and cancer. We need to improve the long-term outcome, by controlling disease activity but also preventing damage and drug toxicity. By contrast, in large vessel vasculitis where mortality is much less but morbidity potentially greater, such as giant cell arteritis (GCA) and Takayasu arteritis, therapeutic options are limited. High dose glucocorticoid results in significant toxicity in over 80%. Advances in understanding the biology of the vasculitides are improving therapies. Novel, mechanism based therapies such as rituximab in AASV, mepolizumab in eosinophilic granulomatosis with polyangiitis, and tocilizumab in GCA, but the lack of reliable biomarkers remains a challenge to progress in these chronic relapsing diseases.