The Human Glucocorticoid Receptor Beta: From Molecular Mechanisms to Clinical Implications

USP10-mediated deubiquitination of NR3C1 regulates bone homeostasis by controlling CST3 expression

Dysregulated bone homeostasis contributes to multiple diseases including osteoporosis (OP). In this study, osteoporotic mice were successfully generated using ovariectomy to investigate the role of nuclear receptor subfamily 3 group C member 1 (NR3C1) in OP. NR3C1, identified as a significantly upregulated gene in OP using bioinformatic tools, was artificially downregulated in osteoporotic mice. NR3C1 expression was significantly elevated in the femoral tissues of osteoporotic patients, and downregulation of NR3C1 alleviated bone loss and restored bone homeostasis in osteoporotic mice, as manifested by increased ALP- and OCN-positive cells and reduced RANKL/OPG ratio. Downregulation of NR3C1 inhibited osteoclastic differentiation of RAW264.7 cells and mouse bone marrow-derived macrophages (BMDM) and promoted osteogenic differentiation of MC3T3-E1 cells. The transcription factor NR3C1 bound to the cystatin-3 (CST3) promoter to repress its transcription in both RAW264.7 and MC3T3-E1 cells. The downregulation of CST3 reversed the protective effect of NR3C1 downregulation against OP. Ubiquitin-specific-processing protease 10 (USP10)-mediated deubiquitination of NR3C1 improved NR3C1 stability. Downregulation of USP10 inhibited osteoclastic differentiation of RAW264.7 cells and BMDM while promoting osteogenic differentiation of MC3T3-E1 cells. Taken together, USP10-mediated deubiquitination of NR3C1 regulates bone homeostasis by controlling CST3 transcription, providing an attractive therapeutic strategy to alleviate OP.

Developmental Neuroendocrinology of Early-Life Stress: Impact on Child Development and Behavior

Our internal balance, or homeostasis, is threatened or perceived as threatened by stressful stimuli, the stressors. The stress system is a highly conserved system that adjusts homeostasis to the resting state. Through the concurrent activation of the hypothalamic-pituitary-adrenal axis and the locus coeruleus/norepinephrine-autonomic nervous systems, the stress system provides the appropriate physical and behavioral responses, collectively termed as "stress response", to restore homeostasis. If the stress response is prolonged, excessive or even inadequate, several acute or chronic stress-related pathologic conditions may develop in childhood, adolescence and adult life. On the other hand, earlylife exposure to stressors has been recognized as a major contributing factor underlying the pathogenesis of non-communicable disorders, including neurodevelopmental disorders. Accumulating evidence suggests that early-life stress has been associated with an increased risk for attention deficit hyperactivity disorder and autism spectrum disorder in the offspring, although findings are still controversial. Nevertheless, at the molecular level, early-life stressors alter the chemical structure of cytosines located in the regulatory regions of genes, mostly through the addition of methyl groups. These epigenetic modifications result in the suppression of gene expression without changing the DNA sequence. In addition to DNA methylation, several lines of evidence support the role of non-coding RNAs in the evolving field of epigenetics. In this review article, we present the anatomical and functional components of the stress system, discuss the proper, in terms of quality and quantity, stress response, and provide an update on the impact of early-life stress on child development and behavior.

[Association of the structure of the glucocorticoid receptor and single nucleotide NR3C1 gene polymorphisms with metabolic disorders]

Glucocorticoid therapy is widely used in the treatment of various pathologies. Sensitivity to glucocorticoids  (GC) has a serious impact not only on the effectiveness of their action, but also on the severity of side effects, the formation of risk factors and the development  of cardiovascular diseases (CVD). Variability of sensitivity to GC causes different phenotypes and severity of metabolic disorders underlying  CVD. Among  them, one can distinguish  a decrease in muscle mass and strength, obesity, glucose and lipid metabolism impairment, and others. Glucocorticoids carry out their effects by binding to the glucocorticoid receptor (GR), and therefore this is considered a critical point in their action. This review presents data on the significance of the glucocorticoid  receptor structure, examines the main single nucleotide polymorphisms (SNP) of the NR3C1 gene associated with hypersensitivity  or relative resistance to glucocorticoids  in the context of metabolic disorders and the development of CVD. The association of the four most studied SNP of the GR gene with metabolic risks is described in detail: BclI (rs41423247), N363S (rs56149945), ER22/23EK (rs6189/rs6190), GR-9ß (rs6198). Their determination can contribute to clarifying the prognosis of both the effectiveness of GC and the development of metabolic disorders, and subsequent early correction of CVD risk factors.