Therapeutic implications of non-genomic glucocorticoid activity

Comparison of chemotherapy outcomes between normal and high serum cortisol concentration in dogs with lymphoma

BACKGROUND

Increased serum cortisol (COR) concentrations may induce glucocorticoid resistance by down-regulation of glucocorticoid receptor (GCR), resulting in decreased chemotherapy efficacy in dogs with lymphoma.

HYPOTHESIS

Investigate the relationship between serum COR concentrations and chemotherapy outcomes in dogs with lymphoma.

ANIMALS

Thirty client-owned dogs with lymphoma, with serum COR concentration measured using serum samples collected at diagnosis.

METHODS

Retrospective study. Dogs were divided into 2 groups based on serum COR concentrations: a normal group (n = 16) with COR concentrations <6 μg/dL and a high group (14) with COR concentrations ≥6 μg/dL. We compared signalment, clinical signs, stage, type of lymphoma, adrenal gland size, alkaline phosphatase (ALP) activity, response to chemotherapy, progression-free survival (PFS), overall survival (OS), and rate of P-glycoprotein (P-gp)- and GCR-positive cells between the 2 groups.

RESULTS

No significant differences were found in the demographic characteristics between the 2 groups. However, the high COR group exhibited a significantly lower response to chemotherapy, PFS, and OS compared with the normal COR group. Serum ALP activity was significantly higher in the high COR group than in the normal COR group. Adrenal gland size was also significantly larger in the high COR group. Although no significant differences were found in the rate of P-gp-positive cells between the 2 groups, the rate of GCR-positive cells was significantly lower in the high COR group.

CONCLUSIONS AND CLINICAL IMPORTANCE

Our data suggests that measurement of serum COR concentrations may serve as a potential prognostic factor and evaluation index.

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.

Glucocorticoid Therapy in COVID-19

Coronavirus disease 2019 (COVID-19) pneumonia caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has resulted in significant mortality in pandemic proportions. Inflammation in response to the infection contributes to the pathogenesis of pneumonia. This review will discuss prior studies on the use of glucocorticoids to treat respiratory infections, the rationale for the use glucocorticoids in COVID-19, and review of existing data. We will also highlight outstanding research questions for future studies.

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.

Non-genomic signaling of steroid receptors in cancer

Steroid receptors (SRs) are members of the nuclear receptor family, which are ligand-activated transcription factors. SRs regulate many physiological functions including development and reproduction, though they can also be involved in several pathologies, especially cancer. Highly controlled cellular responses to steroids involve transcriptional regulation (genomic activity) combined with direct activation of signaling cascades (non-genomic activity). Non-genomic signaling has been extensively studied in cancer, mainly in breast cancer for ER and PR, and prostate cancer for AR. Even though most of the studies have been conducted in cells, some of them have been confirmed in vivo, highlighting the relevance of this pathway in cancer. This review provides an overview of the current and emerging knowledge on non-genomic signaling with a focus on breast and prostate cancers and its clinical relevance. A thorough understanding of ER, PR, AR and GR non-genomic pathways may open new perspectives for the development of therapeutic strategies.

A comparison of intravenous methylprednisolone and hydrocortisone for the treatment of acute inflammatory bowel disease

BACKGROUND AND AIM

Despite widespread recommendations and use of intravenous corticosteroids (IVCS) for the treatment of acute flares of ulcerative colitis and Crohn's disease, limited evidence exists comparing outcomes of the two most common regimens, intravenous methylprednisolone (IVMP) and intravenous hydrocortisone (IVHC). IVHC has stronger mineralocorticoid effects compared with IVMP and may cause higher rates of hypokalemia. We aimed to determine differences in clinical outcomes including requirement for inpatient rescue therapy, bowel resection, and rates of hypokalemia.

METHODS

We conducted a multicenter cohort study of all adult patients admitted with an acute flare of inflammatory bowel disease (IBD) to the three tertiary hospitals in Auckland, New Zealand, where the protocol at each institution is either IVMP 60 mg daily or IVHC 100 mg four times daily. All patients requiring IVCS between 20 June 2016 and 30 June 2018 were included. The IVCS protocol was then changed at one hospital, where further data were collected for a further 12 months from 30 January 2019 until 30 December 2019.

RESULTS

There were 359 patients, including 129 (35.9%) patients receiving IVMP and 230 (64.1%) patients receiving IVHC. IVMP treatment was associated with a greater requirement for rescue therapy than IVHC (36.4% vs 19.6%, P = 0.001; odds ratio [OR] = 2.79; 95% confidence interval [CI], 1.64-4.75, P < 0.001), but also reduced rates of hypokalemia (55.8% vs 67.0%, P = 0.04; OR = 0.49; 95% CI, 0.30-0.81, P = 0.005). There was no difference between treatment groups for the median length of admission (5 days, interquartile range [IQR] 3-8), median duration of IVCS treatment (3 days, IQR 2-5), or bowel resection within 30 days of admission (12.4% vs 11.7%; OR = 1.04).

CONCLUSION

For the treatment of an acute flare of IBD, treatment with IVMP results in significantly more requirement for inpatient rescue biologic or cyclosporin. In addition, it causes statistically significant less hypokalemia than IVHC, although in practice differences are negligible.

Treatment and Evaluation Advances in Leprosy Neuropathy

Neuropathy and related disabilities are the major medical consequences of leprosy, which remains a global medical concern. Despite major advances in understanding the mechanisms of M. leprae entry into peripheral nerves, most aspects of the pathogenesis of leprosy neuropathy remain poorly understood. Sensory loss is characteristic of leprosy, but neuropathic pain is sometimes observed. Effective anti-microbial therapy is available, but neuropathy remains a problem especially if diagnosis and treatment are delayed. Currently there is intense interest in post-exposure prophylaxis with single-dose rifampin in endemic areas, as well as with enhanced prophylactic regimens in some situations. Some degree of nerve involvement is seen in all cases and neuritis may occur in the absence of leprosy reactions, but acute neuritis commonly accompanies both Type 1 and Type 2 leprosy reactions and may be difficult to manage. A variety of established as well as new methods for the early diagnosis and assessment of leprosy neuropathy are reviewed. Corticosteroids offer the primary treatment for neuritis and for subclinical neuropathy in leprosy, but success is limited if nerve function impairment is present at the time of diagnosis. A candidate vaccine has shown apparent benefit in preventing nerve injury in the armadillo model. The development of new therapeutics for leprosy neuropathy is greatly needed.

2021 American College of Rheumatology/Vasculitis Foundation Guideline for the Management of Polyarteritis Nodosa

OBJECTIVE

To provide evidence-based recommendations and expert guidance for the management of systemic polyarteritis nodosa (PAN).

METHODS

Twenty-one clinical questions regarding diagnostic testing, treatment, and management were developed in the population, intervention, comparator, and outcome (PICO) format for systemic, non-hepatitis B-related PAN. Systematic literature reviews were conducted for each PICO question. The Grading of Recommendations Assessment, Development and Evaluation methodology was used to assess the quality of evidence and formulate recommendations. Each recommendation required ≥70% consensus among the Voting Panel.

RESULTS

We present 16 recommendations and 1 ungraded position statement for PAN. Most recommendations were graded as conditional due to the paucity of evidence. These recommendations support early treatment of severe PAN with cyclophosphamide and glucocorticoids, limiting toxicity through minimizing long-term exposure to both treatments, and the use of imaging and tissue biopsy for disease diagnosis. These recommendations endorse minimizing risk to the patient by using established therapy at disease onset and identify new areas where adjunctive therapy may be warranted.

CONCLUSION

These recommendations provide guidance regarding diagnostic strategies, use of pharmacologic agents, and imaging for patients with PAN.

2021 American College of Rheumatology/Vasculitis Foundation Guideline for the Management of Polyarteritis Nodosa

OBJECTIVE

To provide evidence-based recommendations and expert guidance for the management of systemic polyarteritis nodosa (PAN).

METHODS

Twenty-one clinical questions regarding diagnostic testing, treatment, and management were developed in the population, intervention, comparator, and outcome (PICO) format for systemic, non-hepatitis B-related PAN. Systematic literature reviews were conducted for each PICO question. The Grading of Recommendations Assessment, Development and Evaluation methodology was used to assess the quality of evidence and formulate recommendations. Each recommendation required ≥70% consensus among the Voting Panel.

RESULTS

We present 16 recommendations and 1 ungraded position statement for PAN. Most recommendations were graded as conditional due to the paucity of evidence. These recommendations support early treatment of severe PAN with cyclophosphamide and glucocorticoids, limiting toxicity through minimizing long-term exposure to both treatments, and the use of imaging and tissue biopsy for disease diagnosis. These recommendations endorse minimizing risk to the patient by using established therapy at disease onset and identify new areas where adjunctive therapy may be warranted.

CONCLUSION

These recommendations provide guidance regarding diagnostic strategies, use of pharmacologic agents, and imaging for patients with PAN.

Long-term administration of prednisolone: Effects on the myocardial tissue of healthy beagle dogs

This study aimed to assess the structural and functional effects of long-term hyperglucocorticoidemia on canine myocardium and compare these parameters with histopathological changes. Twelve healthy male beagle dogs were enrolled and assigned to the high-dose prednisolone (P; n=6) and control (C; n=6) groups. The P group was treated with 2 mg/kg of prednisolone BID for 84 days. Clinical parameters were measured using echocardiography and non-invasive systolic blood pressure (SBP) measured before the initiation of synthetic corticosteroids and at 7, 28, 56, and 84 days after the start of medication. For histological evaluation, cardiovascular tissue was harvested from dogs in groups P (at the end of the medication period) and C (scheduled to be euthanized for unrelated reasons). In the P group, clinical changes including thickening of the left ventricular free wall (LVFW) and interventricular septum (IVS), decreased left ventricular (LV) diastolic function, and increased SBP were observed after the start of medication. During histological evaluation, fibrosis was observed in the LVFW and IVS in the P group. Furthermore, decreased glucocorticoid receptor (GCR) levels were observed in the LVFW, right ventricular free wall (RVFW), and IVS and increased mineralocorticoid receptor (MCR) levels were observed in the LVFW and RVFW in the P group compared with those in the C group. In conclusion, fibrosis may cause LV structural and functional abnormalities in dogs with hyperadrenocorticism. Furthermore, GCR downregulation and upregulated MCR might influence the myocardial fibrosis.

Diffuse Alveolar Hemorrhage After Pediatric Hematopoietic Stem Cell Transplantation

Pulmonary complications are common following hematopoietic cell transplantation (HCT) and contribute significantly to its morbidity and mortality. Diffuse alveolar hemorrhage is a devastating non-infectious complication that occurs in up to 5% of patients post-HCT. Historically, it carries a high mortality burden of 60–100%. The etiology remains ill-defined but is thought to be due to lung injury from conditioning regimens, total body irradiation, occult infections, and other comorbidities such as graft vs. host disease, thrombotic microangiopathy, and subsequent cytokine release and inflammation. Clinically, patients present with hypoxemia, dyspnea, and diffuse opacities consistent with an alveolar disease process on chest radiography. Diagnosis is most commonly confirmed with bronchoscopy findings of progressively bloodier bronchoalveolar lavage or the presence of hemosiderin-laden macrophages on microscopy. Treatment with glucocorticoids is common though dosing and duration of therapy remains variable. Other agents, such as aminocaproic acid, tranexamic acid, and activated recombinant factor VIIa have also been tried with mixed results. We present a review of diffuse alveolar hemorrhage with a focus on its pathogenesis and treatment options.

Glucocorticoids pharmacology and their application in the treatment of childhood-onset systemic lupus erythematosus

Glucocorticoids are potent anti-inflammatory and immunosuppressant medications and remain the mainstay of systemic lupus erythematosus (SLE) therapy. The potency of a specific glucocorticoid, i.e., the dose of glucocorticoid that is required to produce a specific effect, is dependent on its pharmacokinetic (PK) and pharmacodynamic (PD) properties. In this review, we summarize the PK/PD properties of commonly used glucocorticoids in an attempt to better delineate their role in the management of children with childhood-onset SLE (cSLE). We also address glucocorticoid side effects as these play a major role when deciding on the dose, frequency, and duration of use. A better understanding of the pharmacology of glucocorticoids appears useful to achieve improved outcomes in the management of cSLE.

High-dose intravenous methylprednisolone therapy in patients with Graves' orbitopathy is associated with the increased activity of factor VIII

PURPOSE

Venous thromboembolic events (VTE), with their life-threatening manifestation as pulmonary embolism, are potential adverse effects of intravenous methylprednisolone (IVMP) pulse therapy, partially due to a hypercoagulable state. The aim of the study was to analyze the influence of IVMP on selected hemostatic parameters in patients with moderate-to-severe Graves' orbitopathy (GO).

METHODS

26 euthyroid patients with GO were treated with 12 pulses of IVMP (6 × 0.5, 6 × 0.25 g every week). Hemostatic variables [factor (F) II, FV, FVII, FVIII, fibrinogen, antithrombin, activated partial thromboplastin time (aPTT), prothrombin time, international normalized ratio of prothrombin time, platelets and D-dimer] were analysed before, 24 and 48 h after 1st, 6th and 12th pulse.

RESULTS

A constant, transient trend in changes of some hemostatic variables was observed after all assessed pulses. We discovered an increase in median activity of FVIII 24 and 48 h after pulses, with a shortening of aPTT 24 h after each IVMP pulse (p < 0.00005). FVII decreased 24 h after each pulse (p < 0.0005 after 1st and 12th, p < 0.00005 after 6th). Fibrinogen level decreased 48 h after each pulse (P < 0.00005). We did not observe any statistically significant changes in hemostatic parameters in the long-term evaluation. Therapy was concluded in one patient after the 9th pulse due to pulmonary embolism.

CONCLUSIONS

The increase of FVIII activity is a consequence of treatment with IVMP and occurs after each pulse. In patients with additional risk factors of VTE, anticoagulation prophylaxis should be considered.

Intravenous pulses of methylprednisolone to treat flares of immune-mediated diseases: how much, how long?

Introduction Glucocorticoids are widely used in the treatment of immune-mediated diseases. Despite their widespread use, details on dosing, effectiveness and adverse effects are yet to be determined. Objective To know the current use of methylprednisolone (MTP) in the management of immune-mediated conditions, evaluating the relationship among doses, therapeutic response and adverse effects. Methodology A multicenter retrospective cohort study was designed, including patients who received intravenous pulses of MTP between 1 January 2013 and 12 December 2015 in three different hospitals in Uruguay. The patients included received MTP to treat systemic autoimmune diseases (SADs), hematological, nephrological and neurologic diseases and others. The following variables were analyzed: age, gender, MTP cumulative dose, duration of treatment, clinical response (complete, partial and no response) and adverse effects. Results In total, 164 cases were identified, of which 118 (72%) were female. The median age was 48.4 (SD: 18) years. The indications for MTP included: neuroimmune-mediated 92 (56.1%), SADs 29 (17.5%), hematological 15 (9.1%), nephrological 12 (7.3%) and others 16 (9.9%). The median dose to achieve complete response was 3.2 g (SD: 1.5); the median dose to accomplish a partial response was 3.5 g (SD: 1.25); the median dose for non-responders was 3.3 g (SD 1.2) ( p > 0.05). The median dose in those patients with adverse effects was 3.4 g (SD 1.5) and the median dose for those who did not experience adverse effects was 3.3 g (SD: 1.3) ( p > 0.05). The most frequent adverse effects were infectious (22/164, 13.4%). Diabetics were found to have the highest incidence of adverse effects (13/16, 81%) in comparison to non-diabetics, p < 0.05. Discussion Our study suggests a wide range of doses and duration of treatments with MTP. No major associations were found between clinical response and the use of high MTP doses, but the latter was associated with a large proportion of severe infections. No severe infections were identified with MTP doses lower than 1.5 g. The diabetic population is known to be at risk of experiencing varied adverse effects to MTP. These observations reinforce the need for protocolized use of MTP in order to achieve a better relationship among doses, effectiveness and safety profile.

The novel strategy of glucocorticoid drug development via targeting nongenomic mechanisms

Glucocorticoids (GCs) are widely used in clinical practice as potent anti-inflammatory and immunosuppressive agents. Unfortunately, they can also produce numerous and potentially serious side effects that limit their usage. This problem represents the driving force for the intensive search for novel GCs with a better benefit-risk ratio compared to conventional GCs. GCs are believed to take effects mainly through classical genomic mechanisms, which are also largely responsible for GCs' side effects. However, in addition to these genomic effects, GCs also demonstrate rapid genomic-independent activities. It has become increasingly evident that some of the anti-inflammatory, immunosuppressive, anti-allergic and anti-shock effects of GCs could be mediated through nongenomic mechanisms. Thus, theoretically, trying to use nongenomic mechanisms of GCs more intensively may represent a novel strategy for development of GCs with low side effect profile. The new GCs' drugs will take clinical effects mainly via nongenomic mechanisms and do not execute the classical genomic mechanism to reduce side effects.

Membrane glucocorticoid receptors are localised in the extracellular matrix and signal through the MAPK pathway in mammalian skeletal muscle fibres

KEY POINTS

Many studies have previously suggested the existence of stress hormone receptors on the cell membrane of many cell types, including skeletal muscle fibres; however, the exact localisation of these receptors and how they signal to the rest of the cell is poorly understood. In this study, we investigated the localisation and the mechanism(s) underlying the physiological functions of these receptors in mouse skeletal muscle cells. We found that the receptors were present throughout muscle development and that, in adult muscle fibres, they were localised in the extracellular matrix, satellite cells (muscle stem cells) and close to mitochondria. We also found that they signalled to the rest of the cell by activating enzymes called mitogen-activated protein kinases. From these results we suggest that, at physiological concentrations, stress hormones may be important in skeletal muscle differentiation, repair and regeneration.

ABSTRACT

A number of studies have previously proposed the existence of glucocorticoid receptors on the plasma membrane of many cell types, including skeletal muscle fibres. However, their exact localisation and the cellular signalling pathway(s) they utilise to communicate with the rest of the cell are still poorly understood. In this study, we investigated the localisation and the mechanism(s) underlying the non-genomic physiological functions of these receptors in mouse skeletal muscle cells. The results show that the receptors were localised in the cytoplasm in myoblasts, in the nucleus in myotubes, in the extracellular matrix, in satellite cells and in the proximity of mitochondria in adult muscle fibres. Also, they bound laminin in a glucocorticoid-dependent manner. Treating small skeletal muscle fibre bundles with the synthetic glucocorticoid beclomethasone dipropionate increased the phosphorylation (= activation) of extracellular signal-regulated kinases 1 and 2, c-Jun N-terminal kinase and p38 mitogen-activated protein kinase. This occurred within 5 min and depended on the fibre type and the duration of the treatment. It was also abolished by the glucocorticoid receptor inhibitor, mifepristone, and a monoclonal antibody against the receptor. From these results we conclude that the non-genomic/non-canonical physiological functions of glucocorticoids, in adult skeletal muscle fibres, are mediated by a glucocorticoid receptor localised in the extracellular matrix, in satellite cells and close to mitochondria, and involve activation of the mitogen-activated protein kinase pathway.

How to mechanistically explain the CONDOR study data

Results of the CONDOR study suggest that in osteoarthritis and rheumatoid arthritis patients at elevated risk of gastrointestinal (GI) events, treatment with celecoxib, a cyclooxygenase (COX)-2 selective non-steroidal anti-inflammatory drug (NSAID), demonstrated significantly lower toxicity in the upper and lower (GI) tract when compared to the non-selective NSAID diclofenac plus a proton-pump-inhibitor (PPI), omeprazole. According to current knowledge, traditional NSAIDs (tNSAIDs) as non-selective COX-inhibitors exert their damaging effects on the upper GI tract, largely by reduction of the COX-1 related synthesis of gastro-protective prostaglandins. Thus, the question arises, how NSAIDs do exert their damaging effects especially in the lower GI tract and how to explain the reduced risk of a COX-2 selective inhibitor, celecoxib. Here we hypothesize, that the toxicity of celecoxib on enteral mucosa cells is lower than observed with other NSAIDs, and can be explained COX-independently by typical physicochemical properties of the NSAID substances (e.g., acidic, lipophilic, amphiphilic, surfactant properties). As a consequence these features account for differences in (1) uncoupling effects on mitochondria, (2) effects on cell membrane integrity, and/or (3) formation of "toxic micelles" with bile salts. The evidence for these differences is mainly based on experimental findings. However, several phenomena show differences in extent (e.g., uncoupling effects). The reduced toxicity appears to be rather a substance-specific characteristic. This is an unconditional reason to carry on investigating these phenomena in experimental and large-scale clinical trials.

Why do we need nongenomic glucocorticoid mechanisms?

Glucocorticoids (GCs) are a class of steroid hormones that have been known to be involved in various physiological processes and to play a pivotal role in preserving basal and stress-related homeostasis. GCs are also widely used clinically as anti-inflammatory, immunosuppressive, anti-shock drugs. It is believed traditionally that GCs exert most of their effects genomically. In addition to the well-known classical genomic mechanisms, GCs also affect various functions via rapid, nongenomic mechanisms. The therapeutic benefits of nongenomic GC actions have been exploited in clinical medicine, especially with high-dose pulsed glucocorticoid administration. However, it is certainly not the case that the inherent nongenomic glucocorticoid mechanisms evolved only for their clinical utility. Here, we review the recent literature on nongenomic actions of GCs related to stress and the physiological significance of these actions, and we propose reasons why nongenomic mechanisms of GC actions are needed.

A membrane glucocorticoid receptor mediates the rapid/non-genomic actions of glucocorticoids in mammalian skeletal muscle fibres

Glucocorticoids (GCs) are steroid hormones released from the adrenal gland in response to stress. They are also some of the most potent anti-inflammatory and immunosuppressive drugs currently in clinical use. They exert most of their physiological and pharmacological actions through the classical/genomic pathway. However, they also have rapid/non-genomic actions whose physiological and pharmacological functions are still poorly understood. Therefore, the primary aim of this study was to investigate the rapid/non-genomic effects of two widely prescribed glucocorticoids, beclomethasone dipropionate (BDP) and prednisolone acetate (PDNA), on force production in isolated, intact, mouse skeletal muscle fibre bundles. The results show that the effects of both GCs on maximum isometric force (Po) were fibre-type dependent. Thus, they increased Po in the slow-twitch fibre bundles without significantly affecting that of the fast-twitch fibre bundles. The increase in Po occurred within 10 min and was insensitive to the transcriptional inhibitor actinomycin D. Also, it was maximal at ∼250 nM and was blocked by the glucocorticoid receptor (GCR) inhibitor RU486 and a monoclonal anti-GCR, suggesting that it was mediated by a membrane (m) GCR. Both muscle fibre types expressed a cytosolic GCR. However, a mGCR was present only in the slow-twitch fibres. The receptor was more abundant in oxidative than in glycolytic fibres and was confined mainly to the periphery of the fibres where it co-localised with laminin. From these findings we conclude that the rapid/non-genomic actions of GCs are mediated by a mGCR and that they are physiologically/therapeutically beneficial, especially in slow-twitch muscle fibres.

VBP15, a novel anti-inflammatory and membrane-stabilizer, improves muscular dystrophy without side effects

Absence of dystrophin makes skeletal muscle more susceptible to injury, resulting in breaches of the plasma membrane and chronic inflammation in Duchenne muscular dystrophy (DMD). Current management by glucocorticoids has unclear molecular benefits and harsh side effects. It is uncertain whether therapies that avoid hormonal stunting of growth and development, and/or immunosuppression, would be more or less beneficial. Here, we discover an oral drug with mechanisms that provide efficacy through anti-inflammatory signaling and membrane-stabilizing pathways, independent of hormonal or immunosuppressive effects. We find VBP15 protects and promotes efficient repair of skeletal muscle cells upon laser injury, in opposition to prednisolone. Potent inhibition of NF-κB is mediated through protein interactions of the glucocorticoid receptor, however VBP15 shows significantly reduced hormonal receptor transcriptional activity. The translation of these drug mechanisms into DMD model mice improves muscle strength, live-imaging and pathology through both preventive and post-onset intervention regimens. These data demonstrate successful improvement of dystrophy independent of hormonal, growth, or immunosuppressive effects, indicating VBP15 merits clinical investigation for DMD and would benefit other chronic inflammatory diseases.

Glucocorticoid use and abuse in SLE

Glucocorticoids (GCs) are potent anti-inflammatory and immunosuppressive agents. They act by two different mechanisms: the genomic and the non-genomic pathways. The genomic pathway is considered responsible for many adverse effects of GCs, most of them are time and dose dependent. Observational studies support a relationship between GCs and damage in SLE. GCs have been associated with the development of osteoporosis, osteonecrosis, cataracts, hyperglycaemia, coronary heart disease and cognitive impairment, among others. Although no clinical trial has compared high vs low doses of GCs, some studies have shown the efficacy of medium doses in severe forms of SLE. The dose below which treatment can be considered safe has not been defined, but daily doses <7.5 mg of prednisone seem to minimize adverse effects. Combination therapy with HCQ and the judicious use of immunosuppressive drugs help to keep prednisone therapy within those limits.

Controversy: antenatal steroids

There is no controversy that women at risk of preterm delivery before 32 to 34 weeks' gestational age should be treated with antenatal steroids. Three recent meta-analyses by the Cochrane Collaboration on the benefits of antenatal steroids, the choice of steroid and dosing, and repeat doses of corticosteroids comprehensively summarize the available clinical information to about 2007. However, there are many unanswered questions about which steroid and dose to use and about their use in selected populations. This review focuses on those areas of uncertainty.

A novel strategy for development of glucocorticoids through non-genomic mechanism

Glucocorticoids (GCs) are routinely believed to take effect through genomic mechanisms, which are also largely responsible for GCs' side effects. Beneficial non-genomic effects of GCs have been reported as being independent of the genomic pathway. Here, we synthesized a new type of GCs, which took effect mainly via non-genomic mechanisms. Hydrocortisone was conjugated with glycine, lysine and phenylalanine to get a bigger molecular structure, which could hardly go through the cell membrane. Evaluation of the anti-inflammatory efficacy showed that hydrocortisone-conjugated glycine (HG) and lysine could inhibit neutrophil degranulation within 15 min. HG could inhibit IgE-mediated histamine release from mast cells via a non-genomic pathway, and rapidly alleviate allergic reaction. Luciferase reporter assay showed that HG would not activate the glucocorticoid response element within 30 min, which verified the rapid effects independent of the genomic pathway. The work proposes a novel insight into the development of novel GCs, and provides new tools for experimental study on non-genomic mechanisms.

Nongenomic actions of adrenal steroids in the central nervous system

Mineralocorticoids and glucocorticoids are steroid hormones that are released by the adrenal cortex in response to stress and hydromineral imbalance. Historically, adrenocorticosteroid actions are attributed to effects on gene transcription. More recently, however, it has become clear that genome-independent pathways represent an important facet of adrenal steroid actions. These hormones exert nongenomic effects throughout the body, although a significant portion of their actions are specific to the central nervous system. These actions are mediated by a variety of signalling pathways, and lead to physiologically meaningful events in vitro and in vivo. We review the nongenomic effects of adrenal steroids in the central nervous system at the levels of behaviour, neural system activity, individual neurone activity and subcellular signalling activity. A clearer understanding of adrenal steroid activity in the central nervous system will lead to a better ability to treat human disease as well as reduce the side-effects of the steroid treatments already in use.

High-dose inhaled flunisolide versus budesonide in the treatment of acute asthma exacerbations in preschool-age children

The role of inhaled corticosteroids in asthma exacerbation is debated. We compared high doses of nebulized budesonide versus high doses of nebulized flunisolide, in association with a short-acting beta-2-agonist, in the treatment of moderate asthma exacerbation in preschool children. In this randomized, parallel group, simple blind study, 46 children aged between 3 and 5 years affected by an acute moderate asthma attack were treated with nebulized flunisolide (Group 1) 40 microg/kg twice daily for 7 days and then 20 microg/kg twice daily for 14 days, or with nebulized budesonide (Group 2) 0.5 mg twice daily for 7 days then 0.25 mg twice daily for 15 days. Inhaled salbutamol (MDI+ spacer - 200 microg 4 times daily) was administered during the first 3 days of the study and then as needed. At T0, T7 and T21 days, airway resistances were evaluated with the forced oscillation technique before and after inhalation of inhaled salbutamol (200 mcg). Parents recorded symptoms and drug use on a diary card. Forty children completed the study. Airway resistances were significantly reduced at T7 (p< 0.01 flunisolide; p< 0.05 budesonide) and T21 (p< 0.05 flunisolide; p< 0.05 budesonide) versus T0 in both groups, although at T7 the reduction occurred faster in group 1 than in group 2 (p<0.01). During the first 7 days of treatment, symptom scores decreased in both groups; however, the decrease was greater in group 1 (p< 0.05). High doses of inhaled flunisolide and budesonide are both effective in the management of moderate asthma exacerbations in pre-school-age children, but the flunisolide therapeutic effect was faster than budesonide.

[Repeat doses of prenatal corticosteroids for women at risk of preterm birth: a difficult consensus]

A single course of antenatal corticosteroids in women at risk of preterm delivery reduces the risk of neonatal mortality and morbidity. Recent experimental and clinical studies have stated early, medium and long term consequences of single or repeated courses of antenatal corticosteroids. Betamethasone and dexamethasone are the two molecules usually used. Benefits are observed until the first 24 hours after the first injection. Single-course corticosteroids are not effective in babies born more than 7 days after initial treatment. Benefits of corticosteroids were evaluated between 22 and 35 weeks of gestation. Antenatal exposure to single-course betamethasone might result in disruption on glucose metabolism in adult offspring. Weekly courses of prenatal corticosteroids therapy are not recommended. Repeat prenatal corticosteroids given to women at continuing risk of preterm birth 7 or more days after an initial course reduced the inherent respiratory complications of prematurity and improved health outcomes of preterm infants. However, adverse outcomes have been reported concerning cognitive development. Although repeat course may have short term benefits, whether there are effects on health into childhood and beyond must await later assessment. Long term data are needed to recommend repeated courses.

Management of glucocorticoids-induced osteoporosis: role of teriparatide

Glucocorticoids (GC)-induced osteoporosis (GIOP) is the most common cause of secondary osteoporosis, which leads to an increased fracture risk in patients. The normal bone turnover depends on a balance between osteoblasts and osteoclasts activity and GC can cause a rapid bone loss, decreasing bone formation and increasing bone resorption. The decreased bone formation is mainly due to the GC-induced apoptosis of both osteoblasts and osteocytes, while the increased bone resorption is due to the increased life-span of pre-existing osteoclasts. Bisphosphonates are clearly effective in preventing and treating GIOP but anabolic therapeutic strategies are the new promising therapeutic alternative. Experimental and clinical studies indicate that teriparatide, the active (1–34) parathyroid hormone (PTH) molecule, is efficacious for the treatment of GIOP, being able to induce an increase in bone mass in these patients. Intermittent administration of human PTH (1–34) stimulates bone formation by increasing osteoblast number. Additionally, human PTH (1–34) modulates the level and/or activity of locally produced growth factors and cytokines. Teriparatide has been demonstrated in several clinical studies to significantly decrease the incidence of fractures in patients affected by GIOP. It has recently received an indication for GIOP and its label indication has also been expanded.

Mechanisms regulating the susceptibility of hematopoietic malignancies to glucocorticoid-induced apoptosis

Glucocorticoids (GCs) are commonly used in the treatment of hematopoietic malignancies owing to their ability to induce apoptosis of these cancerous cells. Whereas some types of lymphoma and leukemia respond well to this drug, others are resistant. Also, GC-resistance gradually develops upon repeated treatments ultimately leading to refractory relapsed disease. Understanding the mechanisms regulating GC-induced apoptosis is therefore uttermost important for designing novel treatment strategies that overcome GC-resistance. This review discusses updated data describing the complex regulation of the cell's susceptibility to apoptosis triggered by GCs. We address both the genomic and nongenomic effects involved in promoting the apoptotic signals as well as the resistance mechanisms opposing these signals. Eventually we address potential strategies of clinical relevance that sensitize GC-resistant lymphoma and leukemia cells to this drug. The major target is the nongenomic signal transduction machinery where the interplay between protein kinases determines the cell fate. Shifting the balance of the kinome towards a state where Glycogen synthase kinase 3alpha (GSK3alpha) is kept active, favors an apoptotic response. Accumulating data show that it is possible to therapeutically modulate GC-resistance in patients, thereby improving the response to GC therapy.

Neonatal dexamethasone treatment for chronic lung disease of prematurity alters the hypothalamus-pituitary-adrenal axis and immune system activity at school age

OBJECTIVE

To compare long-term effects of neonatal treatment with dexamethasone or hydrocortisone for chronic lung disease of prematurity on the hypothalamus-pituitary-adrenal axis and the immune response in children at school age.

PATIENTS AND METHODS

A total of 156 prematurely born children were included in this retrospective matched cohort study. Children treated with dexamethasone (n = 52) or hydrocortisone (n = 52) were matched for gestational age, birth weight, grade of infant respiratory distress syndrome, grade of periventricular or intraventricular hemorrhage, gender, and year of birth. A reference group of 52 children not treated with corticosteroids was included for comparison. Plasma adrenocorticotropic hormone and cortisol in response to a social stress task were determined. Cytokine production was analyzed after in vitro stimulation of whole-blood cultures.

RESULTS

The Trier Social Stress Test adapted for children induced an adrenocorticotropic hormone and cortisol response in all of the groups. The adrenocorticotropic hormone response was blunted in the dexamethasone group. The overall cortisol level was lower in the dexamethasone than in the hydrocortisone and reference group. Cortisol and adrenocorticotropic hormone in the hydrocortisone and reference groups were similar. The ratio of T-cell mitogen-induced interferon-gamma/interleukin-4 secretion was significantly higher in the dexamethasone group than in the hydrocortisone group. Interferon-gamma production and the ratios of interferon-gamma/interleukin-4 and interferon-gamma/ interleukin-10 were significantly higher in the dexamethasone group than the reference group. However, production of these cytokines did not differ between the hydrocortisone and the reference groups.

CONCLUSION

Neonatal treatment of prematurely born children with dexamethasone but not with hydrocortisone resulted in long-lasting programming effects on hypothalamus-pituitary-adrenal axis and on the T-helper 1/T-helper 2 cytokine balance. Follow-up of these children is required to investigate long-term clinical consequences. We recommend that authors of previously performed randomized, controlled trials on neonatal glucocorticoid treatment include immune and neuroendocrine analyses in prolonged follow-up of these children.

Corticosteroids in perinatal medicine: how to improve outcomes without affecting the developing brain?

Antenatal glucocorticoid therapy remains one of the most striking successes in the perinatal management of complicated pregnancies that result in premature birth. The anti-inflammatory and maturative properties of fluorocorticoids are such that all women at risk of preterm delivery before 34weeks gestation should be treated. Betamethasone is preferred to dexamethasone and no more than two courses, 2weeks apart, should be given until the evidence from further controlled trials on repeated doses becomes available. In particular, the early use of postnatal dexamethasone should be avoided in preterm infants because of the deleterious effects on neurological development, including not only cerebral palsy but also cognitive function and psychiatric-related behavior. Treatment with other steroids should be restricted to the context of randomized controlled trials.

Duodenal calcium absorption in dexamethasone-treated mice: functional and molecular aspects

Reduced intestinal calcium absorption may be part of the pathogenesis of glucocorticoid-induced osteoporosis. 1,25(OH)2D3 is the major regulator of the expression of the active duodenal calcium absorption genes: TRPV6 (influx), calbindin-D9K (intracellular transfer) and PMCA1b (extrusion). We investigated the influence of dexamethasone (5 days: 2 mg/kg bw) on calcium absorption in vivo and on the expression of intestinal and renal calcium transporters in calcium-deprived mice. Total and free 1,25(OH)2D3-concentrations were halved, in line with decreased 25(OH)D3-1-alpha-hydroxylase and increased 24-hydroxylase expression. Nevertheless, no difference in duodenal or renal calcium transporter expression pattern could be detected between vehicle and dexamethasone-treated mice. Accordingly, dexamethasone did not affect in vivo calcium absorption. By contrast, increased calcemia and collagen C-terminal telopeptide levels reflected increased bone resorption. Decreased osteocalcin levels suggested impaired bone formation. Hence, short-term glucocorticoid excess in young animals affected bone metabolism without detectable changes in intestinal or renal calcium handling.

Glucocorticoid Receptor Activation Signals through Forkhead Transcription Factor 3a in Breast Cancer Cells

Activation of the glucocorticoid receptor (GR) plays a critical role in the stress response of virtually all cell types. Despite recent advances in large-scale genomic and proteomic data acquisition, identification of physiologically relevant molecular events downstream of nuclear hormone receptor activation remains challenging. By analyzing gene expression changes 30 min after dexamethasone (Dex) treatment, we previously found that immediate induction of serum and glucocorticoid-regulated kinase-1 (SGK-1) expression is required for GR-mediated mammary epithelial cell survival signaling. We now report that activation of the GR mediates Forkhead transcription factor 3a (FOXO3a) phosphorylation and inactivation in mammary epithelial cells. GR-mediated induction of SGK-1 expression is required for FOXO3a inactivation; additional growth factor stimulation is not required. To further explore the gene expression changes that occur downstream of GR-mediated FOXO3a inactivation, we analyzed temporal gene expression data and selected GR-down-regulated genes containing core FOXO3a binding motifs in their proximal promoters. This approach revealed several previously unrecognized transcriptional target genes of FOXO3a, including IGF binding protein-3 (IGFBP-3). Endogenous IGFBP-3 expression was confirmed to be dependent on the GR-SGK-1-FOXO3a signaling pathway. Moreover, GR activation decreased FOXO3a-induced apoptosis in SK-BR-3 breast cancer cells. Collectively, our data suggest that GR-mediated FOXO3a inactivation is an important mechanism contributing to glucocorticoid-mediated mammary epithelial cell survival.

Dexamethasone protection from TNF-alpha-induced cell death in MCF-7 cells requires NF-kappaB and is independent from AKT

Background

The biochemical bases for hormone dependence in breast cancer have been recognized as an important element in tumor resistance, proliferation and metastasis. On this respect, dexamethasone (Dex) dependent protection against TNF-alpha-mediated cell death in the MCF-7 cell line has been demonstrated to be a useful model for the study of this type of cancer. Recently, cytoplasmic signaling induced by steroid receptors has been described, such as the activation of the PI3K/Akt and NF-kappaB pathways. We evaluated their possible participation in the Dex-dependent protection against TNF-alpha-mediated cell death.

Results

Cellular cultures of the MCF-7 cell line were exposed to either, TNF-alpha or TNF-alpha and Dex, and cell viability was evaluated. Next, negative dominants of PI3K and IkappaB-alpha, designed to block the PI3K/Akt and NF-kappaB pathways, respectively, were transfected and selection and evaluation of several clones overexpressing the mutants were examined. Also, correlation with inhibitor of apoptosis proteins (IAPs) expression was examined. Independent inhibition of these two pathways allowed us to test their participation in Dex-dependent protection against TNF-alpha-cytotoxicity in MCF-7 cells. Expression of the PI3K dominant negative mutant did not alter the protection conferred by Dex against TNF-alpha mediated cell death. Contrariwise, clones expressing the IkappaB-alpha dominant negative mutant lost the Dex-conferred protection against TNF-alpha. In these clones degradation of c-IAP was accelerated, while that of XIAP was remained unaffected.

Conclusion

NF-kappaB, but not PI3K/Akt activation, is required for the Dex protective effect against TNF-alpha-mediated cell death, and correlates with lack of degradation of the anti-apoptotic protein c-IAP1.

Comparison of fetal and adult marrow stromal cells in osteogenesis with and without glucocorticoids

To better understand the potential use of fetal marrow stromal cells (MSCs) in bone tissue engineering, we compared the ability of these cells with those of adult MSCs with respect to osteoblasts differentiation in the presence or absence of glucocorticoids. Cells were grown for 3-4 weeks in basal medium or supplemented with 100 nM dexamethasone (DEX, a synthetic glucocorticoid analog) or with 50 microM L-ascorbate and 10 mM glycerol-2-phosphate (AS+GP) or with AS+GP+DEX. At various time points in culture, the following parameters were compared between fetal and adult MSCs: cell morphology, cell proliferation, alkaline phosphatase activity, calcium (45Ca) uptake, von Kossa staining, and glucocorticoids receptor expression were analyzed. Compared with adult MSCs, fetal cells showed a less dramatic change to cuboidal morphology in DEX-containing media. Fetal MSCs in all media conditions showed higher proliferation rates and lower alkaline phosphatase activities (p < 0.001) than adult cells. Both fetal and adult MSCs responded similarly in DEX-containing media with respect to suppressing cell proliferation, stimulating alkaline phosphatase activity, and consistently accumulating calcium (usually higher in fetal cells) with subsequent formation of mineralized matrix when compared with cells cultured in AS+GP. Our findings further implicate the requirement of glucocorticoids in osteogenesis. In conclusion, compared with adult MSCs, fetal cells showed greater ability in sustaining cell proliferation and calcium uptake suggesting that they may be useful for bone tissue repair.

Genomic and non-genomic effects of different glucocorticoids on mouse thymocyte apoptosis

Glucocorticoids, widely used therapeutic agents for several pathologies, act upon diverse cells and tissues, including the lympho-haemopoietic system. Glucocorticoid-mediated apoptosis has been described as one of the mechanisms underlying their pharmacological and physiological effects. Glucocorticoids induce apoptosis in thymocytes through genomic and non-genomic signals. We tested thymocyte apoptosis rates as induced by a panel of glucocorticoids. Using four glucocorticoids that are widely adopted in clinical practice we compared their induction of thymocyte apoptosis and activation of non-genomic and genomic signals, including phosphatidylinositol-specific phospholipase C (PI-PLC), caspase-8, -9 and -3, and Glucocorticoid-Induced Leucine Zipper (GILZ). GILZ is a protein that is rapidly induced by glucocorticoids treatment and involved in apoptosis modulation. Results indicate different glucocorticoids have different apoptotic activity which is related to their ability to induce both genomic, evaluated as caspases activation and GILZ expression, and non-genomic effects, evaluated as PI-PLC phosphorylation.

[Adrenal cortex and steroids. Supplementary therapy in the perioperative phase]

Since the publication of two case reports that are considered to represent the first clinical demonstration of iatrogenic adrenal insufficiency, it has been the generally accepted practice to cover steroid-treated patients undergoing surgery with glucocorticoids in the perioperative period. Both the inclusion criteria for the patients and the extent of the substitution pattern have been selected on an empirical rather than on a rational basis. Scientific advances over the past 50 years in the knowledge of the hypothalamic-pituitary-adrenal system's physiology and the molecular mechanism of action of its biologically active components are, for the most part, not reflected in current clinical practice and instead seem to be ignored. Clinical and experimental evidence suggests, however, that even glucocorticoid-treated patients undergoing surgery do not require maximum stress doses of hydrocortisone, which should be reserved for the treatment of sepsis. With regard to the broad spectrum of efficacy of glucocorticoids and their side effects, revision and modification of the historical regimen appear prudent.

Management of Bronchopulmonary Dysplasia in Infants

Bronchopulmonary dysplasia (BPD) is a common cause of morbidity and mortality in preterm neonates and at present its management is unclear. Over the past three decades there has been a growing use of corticosteroids in the postnatal period; first for the treatment and then, more recently, for the prevention of BPD. The first published use of corticosteroids to treat neonatal lung disease was in 1956; however, it was only in the 1980s and 1990s that their use in neonates became commonplace. Concerns about their long-term neurodevelopmental consequences arose in the late 1990s when follow-up of randomised controlled trials indicated an increased risk of cerebral palsy after postnatal dexamethasone exposure. Dexamethasone has been the most frequently used corticosteroid in neonatal units, although others, including hydrocortisone, prednisolone and methylprednisolone, have been studied, as have inhaled corticosteroids. Systematic reviews indicate that systemic corticosteroids improve respiratory function in the short term and expedite extubation in preterm neonates. However, there is a high risk of hypertension, hyperglycaemia and gastrointestinal complications in corticosteroid-treated neonates and, if administered in the first 4 days of life, an association with long-term neurodevelopmental delay. There should be emphasis on prevention of BPD by reducing the risk factors associated with its development. There is no role for use of corticosteroids in the first 4 days of life as the high risk of long-term adverse effects outweighs any likely short-term benefits. Corticosteroid use should be limited to exceptional clinical circumstances, such as a ventilator-dependent infant after the second week of life who cannot be weaned from ventilation and whose condition is worsening. If used, they should be prescribed at the lowest effective dose for the shortest possible time. Further randomised trials of low-dose corticosteroids given after the first week of life are warranted and should assess both short- and long-term outcomes.

Glucocorticoid receptor-induced MAPK phosphatase-1 (MPK-1) expression inhibits paclitaxel-associated MAPK activation and contributes to breast cancer cell survival

Glucocorticoid receptor (GR) activation has recently been shown to inhibit apoptosis in breast epithelial cells. We have previously described a group of genes that is rapidly up-regulated in these cells following dexamethasone (Dex) treatment. In an effort to dissect the mechanisms of GR-mediated breast epithelial cell survival, we now examine the molecular events downstream of GR activation. Here we show that GR activation leads to both the rapid induction of MAPK phosphatase-1 (MKP-1) mRNA and its sustained expression. Induction of the MKP-1 protein in the MCF10A-Myc and MDA-MB-231 breast epithelial cell lines was also seen. Paclitaxel treatment resulted in MAPK activation and apoptosis of MDA-MB-231 breast cancer cells, and both processes were inhibited by Dex pretreatment. Furthermore, induction of MKP-1 correlated with the inhibition of extracellular signal-regulated kinase (ERK1/2) and c-Jun N-terminal kinase (JNK) activity, whereas p38 activity was minimally affected. Blocking Dex-induced MKP-1 induction using small interfering RNA increased ERK1/2 and JNK phosphorylation and decreased cell survival. ERK1/2 and JNK inactivation was associated with Ets-like transcription factor-1 (ELK-1) dephosphorylation. To explore the gene expression changes that occur downstream of ELK-1 dephosphorylation, we used a combination of temporal gene expression data and promoter element analyses. This approach revealed a previously unrecognized transcriptional target of ELK-1, the human tissue plasminogen activator (tPA). We verified the predicted ELK-1--> tPA transcriptional regulatory relationship using a luciferase reporter assay. We conclude that GR-mediated MAPK inactivation contributes to cell survival and that the potential transcriptional targets of this inhibition can be identified from large scale gene array analysis.