A Novel Human Glucocorticoid Receptor Variant, G459V, is Hyperactive in Response to Steroids

Treating the Side Effects of Exogenous Glucocorticoids; Can We Separate the Good From the Bad?

It is estimated that 2% to 3% of the population are currently prescribed systemic or topical glucocorticoid treatment. The potent anti-inflammatory action of glucocorticoids to deliver therapeutic benefit is not in doubt. However, the side effects associated with their use, including central weight gain, hypertension, insulin resistance, type 2 diabetes (T2D), and osteoporosis, often collectively termed iatrogenic Cushing's syndrome, are associated with a significant health and economic burden. The precise cellular mechanisms underpinning the differential action of glucocorticoids to drive the desirable and undesirable effects are still not completely understood. Faced with the unmet clinical need to limit glucocorticoid-induced adverse effects alongside ensuring the preservation of anti-inflammatory actions, several strategies have been pursued. The coprescription of existing licensed drugs to treat incident adverse effects can be effective, but data examining the prevention of adverse effects are limited. Novel selective glucocorticoid receptor agonists and selective glucocorticoid receptor modulators have been designed that aim to specifically and selectively activate anti-inflammatory responses based upon their interaction with the glucocorticoid receptor. Several of these compounds are currently in clinical trials to evaluate their efficacy. More recently, strategies exploiting tissue-specific glucocorticoid metabolism through the isoforms of 11β-hydroxysteroid dehydrogenase has shown early potential, although data from clinical trials are limited. The aim of any treatment is to maximize benefit while minimizing risk, and within this review we define the adverse effect profile associated with glucocorticoid use and evaluate current and developing strategies that aim to limit side effects but preserve desirable therapeutic efficacy.

Changes in Cortisol Secretion and Corticosteroid Receptors in COVID-19 and Non COVID-19 Critically Ill Patients with Sepsis/Septic Shock and Scope for Treatment

Sepsis is associated with dysregulated cortisol secretion, leading to abnormal levels of cortisol in the blood. In the early stages of the condition, cortisol levels are typically elevated due to increased secretion from the adrenal glands. However, as the disease progresses, cortisol levels may decline due to impaired adrenal function, leading to relative adrenal insufficiency. The latter is thought to be caused by a combination of factors, including impaired adrenal function, decreased production of corticotropin-releasing hormone (CRH) and adrenocorticotropic hormone (ACTH) by the hypothalamus and pituitary gland, and increased breakdown of cortisol. The dysregulation of cortisol secretion in sepsis is thought to contribute to the pathophysiology of the disease by impairing the body's ability to mount an appropriate inflammatory response. Given the dysregulation of cortisol secretion and corticosteroid receptors in sepsis, there has been considerable interest in the use of steroids as a treatment. However, clinical trials have yielded mixed results and corticosteroid use in sepsis remains controversial. In this review, we will discuss the changes in cortisol secretion and corticosteroid receptors in critically ill patients with sepsis/septic shock. We will also make special note of COVID-19 patients, who presented a recent challenge for ICU management, and explore the scope for corticosteroid administration in both COVID-19 and non-COVID-19 septic patients.

BACTERIAL PATHOGEN-ASSOCIATED MOLECULAR PATTERNS UPREGULATE HUMAN GLUCOCORTICOID RECEPTOR EXPRESSION IN PERIPHERAL BLOOD MONONUCLEAR CELLS

ABSTRACT

It is well known that bacterial components (pathogen-associated molecular patterns [PAMPs]) induce a proinflammatory response through pattern recognition receptor signaling. What is not known, however, is how the inflammatory response is downregulated. We hypothesize that bacterial products initiate compensatory anti-inflammatory responses by inducing expression of the human glucocorticoid receptor (hGR). Peripheral blood mononuclear cells (PBMCs) were isolated from leukocytes concentrated from single human donors (Leukopaks). PBMCs were treated with a gram-negative bacterial component, LPS, or gram-positive bacterial components, lipoteichoic acid (LTA) or peptidoglycan (PGN), for 1, 3, or 13 h. Protein expression of hGR was evaluated by Western blot analysis. RNA was extracted from similarly treated cells for reverse transcription-polymerase chain reaction analysis of hGR and cytokine expression. At 13 h after LPS treatment, there was an increase in the reference hGR protein (hGRα) expressed within some but not all PBMCs isolated from Leukopaks. There was also a dose-dependent increase in hGRα expression with increasing concentrations of PGN (10 and 50 μg/mL). LTA, however, did not affect hGRα expression. PGN also increased the mRNA expression of an hGR splice variant, hGR-B(54). The mRNA expression changes for the inflammatory cytokines were Leukopak specific. We found that cell wall components of both gram-positive and gram-negative bacteria can increase the expression of hGRα. Although these PAMPs augment the inflammatory response, it seems that there is a simultaneous upregulation of hGRα expression. Because binding of cortisol to hGRα typically induces anti-inflammatory proteins, the same PAMPs that induce an inflammatory response seem to also initiate a negative feedback system by inducing hGRα expression in PBMCs.

Primary Generalized Glucocorticoid Resistance and Hypersensitivity Syndromes: A 2021 Update

Glucocorticoids are the final products of the neuroendocrine hypothalamic-pituitary-adrenal axis, and play an important role in the stress response to re-establish homeostasis when it is threatened, or perceived as threatened. These steroid hormones have pleiotropic actions through binding to their cognate receptor, the human glucocorticoid receptor, which functions as a ligand-bound transcription factor inducing or repressing the expression of a large number of target genes. To achieve homeostasis, glucocorticoid signaling should have an optimal effect on all tissues. Indeed, any inappropriate glucocorticoid effect in terms of quantity or quality has been associated with pathologic conditions, which are characterized by short-term or long-lasting detrimental effects. Two such conditions, the primary generalized glucocorticoid resistance and hypersensitivity syndromes, are discussed in this review article. Undoubtedly, the tremendous progress of structural, molecular, and cellular biology, in association with the continued progress of biotechnology, has led to a better and more in-depth understanding of these rare endocrinologic conditions, as well as more effective therapeutic management.