Research advances concerning the mechanism of glucocorticoid resistance in relation to traditional Chinese medicine for patients with chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease is a common,highly disabling,and burdensome disease.Anti-inflammatory glucocorticoid medication plays a key role in its treatment;however,glucocorticoid resistance in patients with chronic obstructive pulmonary disease considerably weakens the effects of the treatment.Despite recent advances in determining the mechanism of glucocorticoid resistance in patients with chronic obstructive pulmonary disease,the role of traditional Chinese medicine in treating such patients remains unclear.In this review,we reviewed the mechanism of chronic obstructive pulmonary disease-related glucocorticoid resistance with reference to the glucocorticoid receptor,the important signaling pathways(phosphatidylinositol-3-kinase/protein kinase B signaling pathway,p38 mitogen-activated protein kinase signaling pathway,and interferon-γ/Janus kinase/stransducer and activator of transcription signaling pathway),histone deacetylase,nuclear transcription factor-κB,exosomes,and microRNA.Moreover,the methods of establishing the glucocorticoid resistance model associated with chronic obstructive pulmonary disease and advances in therapeutic approaches including traditional Chinese medicine to restore chronic obstructive pulmonary disease glucocorticoid sensitivity have also been reviewed.This review shows that traditional Chinese medicine reverses glucocorticoid resistance mainly by regulating the expression of glucocorticoid receptor,p38 mitogen-activated protein kinase signaling,histone deacetylase 2,and nuclear transcription factor-κB in chronic obstructive pulmonary disease models.Future research is suggested to evaluate traditional Chinese medicine understanding of chronic obstructive pulmonary disease-related glucocorticoid resistance in relation to exosomes,microRNA,and other signaling pathways.

Association analysis of BclI with benign lymphoepithelial lesions of the lacrimal gland and glucocorticoids resistance

AIM:To evaluate the relationship between gene polymorphism(BclI,ER22/23EK,N363S)and the occurrence,progression and sensitivity to glucocorticoid of lacrimal gland benign lymphoepithelial lesion(LGBLEL).METHODS:Clinical peripheral blood samples of 52 LGBLEL patients and 10 normal volunteers were collected for DNA extraction and polymerase chain reaction sequencing to analyze single nucleotide polymorphism(SNP)genotypes.The lacrimal tissues of LGBLEL were surgically removed and made into paraffin sections for subsequent hematoxylin-eosin(HE)and Masson staining analysis.The duration of disease and hormone use of LGBLEL patients from diagnosis to surgery were also analyzed.The Meta-analysis follows PRISMA guidelines to conducted a systematic review of human studies investigating the relationship between the NR3C1 BclI polymorphism and glucocorticoids(GCs)sensitivity.RESULTS:There was no association between ER22/23EK or N363S and the occurrence of LGBLEL or GCs sensitivity(P>0.05);BclI GC genotype was closely related to GCs resistance(P=0.03)as is the minor allele C(P=0.0017).The HE staining and Masson staining showed that the GC genotype of BclI remarkably slowed down the disease progression and reduced fibrosis(P<0.05),especially for GCs-dependent patients(P<0.0001).Meta-analysis showed that BclI was not significantly associated with GCs responsiveness.CONCLUSION:The LGBLEL patients who carry the NR3C1 BclI allele C may be more sensitive to GCs and associated with lower fibrosis and slower disease progression.The results may guide the clinical treatment strategy for the LGBLEL patients.

Generalized glucocorticoid resistance accompanied with an adrenocortical adenoma and caused by a novel point mutation of human glucocorticoid receptor gene

Background Generalized glucocorticoid resistance syndrome is a rare familial or sporadic condition characterized by generalized, partial, target-tissue insensitivity to glucocorticoids. This syndrome is partially caused by mutations in human glucocorticoid receptor （hGR） gene. The clinical spectrum of generalized glucocorticoid resistance is broad, ranging from fatigue or no symptoms to severe hypertension with hypokalemic alkalosis. The purpose of this study was to explore the genetic disorder of glucocorticoid resistance syndrome.Methods We identified a 56-year-old male patient diagnosed with generalized glucocorticoid resistance syndrome accompanied with an adrenocortical adenoma. This asymptomatic patient referred to Peking Union Medical College Hospital for treatment of his adrenal incidentaloma. Endocrinological evaluation consistently revealed his elevated serum cortisol level. Total RNA was extracted from the patient＇s peripheral blood mononuclear leukocytes （PBMLs） and entire coding region of hGR alpha was amplified by reverse transcription （RT）-PCR. To confirm the possible mutation identified by sequencing RT-PCR products, genomic DNA sequence of hGR gene from the patient and 50 healthy controls was analyzed by PCR and directly sequencing.Results A heterozygotic （C→T） substitution at nucleotide position of 1667 （exon 5） in GR alpha gene was found in this patient by sequencing of RT-PCR products of hGR gene. This substitution was also identified at genomic DNA level and it was absent in 100 chromosomes from 50 unrelated health controls. This substitution resulted in a threonine to isoleucine substitution （ACT→ATT） at amino acid 556 in the ligand-binding domain of GR alpha. Conclusion Generalized glucocorticoid resistance in this patient might be caused by a novel heterozygotic mutation in the ligand-binding domain of the GR alpha.

Rapamycin Sensitizes Glucocorticoid Resistant Acute Lymphoblastic Leukemia CEM-C1 Cells to Dexamethasone Induced Apoptosis through both mTOR Suppression and Up-Regulation and Activation of Glucocorticoid Receptor

Objective To explore the role of glucocorticoid （GC） receptor （GR） in rapamycin＇s reversion of GC resistance in humanGC-resistant T-acute lymphoblastic leukemia （ALL） CEM-C1 cells. Methods CEM-C1 cells were cultured in vitro and treated with rapamycin at different concentrations with or without 1 μmol/L dexamethasone （Dex）. 3-（4, 5-dimethylthiazol-2-yl）-2, 5-diphenyltetrazolium bromide （MTT） test was performed to assess cell proliferation. The cell cycle and cell apoptosis were analyzed by flow cytometry. The expression of GRα mRNA was determined by real-time quantitative RT-PCR. The expression of GR, p-70S6K, Mcl-1, and Bim proteins was detected by Western blot. Results When incubated with rapamycin at different concentrations, CEM-C1 cells showed significant growth inhibition in a time- and concentration-dependent manner. The growth inhibition was synergistically increased when CEM-C1 cells were treated with rapamycin plus 1 μmol/L Dex. CEM-C1 cells treated with rapamycin alone showed no apparent apoptosis, and were arrested at G0/G1 phase. After the treatment with Dex plus rapamycin, CEM-C1 cells demonstrated apparent apoptosis and increased the cell cycle arrested at G0/G1 phase. Rapamycin combined with Dex up-regulated GRα, phosphorylated GR（p-GR）, and pro-apoptotic protein Bim-EL in CEM-C1 cells, but inhibited the expression of p-p70S6K, a downstream target protein ofmTOR （mammalian target of rapamycin）. Conclusion After the treatment with rapamycin plus Dex, Dex resistant CEM-C1 cells induce growth inhibition and apoptosis. The underlying mechanism may involve inhibition of the mTOR signaling pathway and also be associated with up-regulation of GR expression and activation of GC-GR signaling pathway.

Effect of Dexamethasone on Expression of Glucocorticoid Receptor in Human Monocyte Cell Line THP-1

The effect of dexamethasone with different concentrations and different stimulating periods on the expression of glucocorticoid receptors （GRα, GRβ） protein was investigated in human monocyte cell line THP-1. The cultured human monocyte line THP-1 cells were stimulated by dexamethasone with different concentrations and different periods. The expression of GRα and GRβ protein was detected by Western hlotting. The results showed that the expression of GRα and GRβ was detected in the THP-1 cells, The quantity of GRα expression was reduced by dexamethasone under the same concentration with the prolongation of expression was increased by dexamethasone treatment the stimulating periods. The quantity of GRβ in a time- and dose-dependent manner. It was concluded that dexamethasone stimulation time-dependently reduced the GRα expression in THP-1 cells. Dexamethasone stimulation time- and dose-dependently increased the GRβ expression in THP- 1 cells. The expression of GRα and GRβas regulated by glucocorticoid.

Glucocorticosteroid therapy in inflammatory bowel diseases: From clinical practice to molecular biology

Inflammatory bowel diseases(IBDs),such as ulcerative colitis and Crohn's disease,are chronic pathologies associated with a deregulated immune response in the intestinal mucosa,and they are triggered by environmental factors in genetically susceptible individuals.Exogenous glucocorticoids(GCs)are widely used as anti-inflammatory therapy in IBDs.In the past,patients with moderate or severe states of inflammation received GCs as a first line therapy with an important effectiveness in terms of reduction of the disease activity and the induction of remission.However,this treatment often results in detrimental side effects.This downside drove the development of second generation GCs and more precise(non-systemic)drugdelivery methods.Recent clinical trials show that most of these new treatments have similar effectiveness to first generation GCs with fewer adverse effects.The remaining challenge in successful treatment of IBDs concerns the refractoriness and dependency that some patients encounter during GCs treatment.A deeper understanding of the molecular mechanisms underlying GC response is key to personalizing drug choice for IBDs patients to optimize their response to treatment.In this review,we examine the clinical characteristics of treatment with GCs,followed by an in depth analysis of the proposed molecular mechanisms involved in its resistance and dependence associated with IBDs.This thorough analysis of current clinical and biomedical literature may help guide physicians in determining a course of treatment for IBDs patients and identifies important areas needing further study.

Using optogenetics to translate the “inflammatory dialogue” between heart and brain in the context of stress

Inflammatory processes are an integral part of the stress response and are likely to result from a programmed adaptation that is vital to the organism＇s survival and well-being.The whole inflammatory response is mediated by largely overlapping circuits in the limbic forebrain,hypothalamus and brainstem,but is also under the control of the neuroendocrine and autonomic nervous systems.Genetically predisposed individuals who fail to tune the respective contributions of the two systems in accordance with stressor modality and intensity after adverse experiences can be at risk for stress-related psychiatric disorders and cardiovascular diseases.Altered glucocorticoid（GC） homeostasis due to GC resistance leads to the failure of neural and negative feedback regulation of the hypothalamic-pituitary-adrenal axis during chronic inflammation,and this might be the mechanism underlying the ensuing brain and heart diseases and the high prevalence of co-morbidity between the two systems.By the combined use of light and genetically-encoded lightsensitive proteins,optogenetics allows cell-type-specific,fast（millisecond-scale） control of precisely defined events in biological systems.This method is an important breakthrough to explore the causality between neural activity patterns and behavioral profiles relevant to anxiety,depression,autism and schizophrenia.Optogenetics also helps to understand the ＂inflammatory dialogue＂,the inflammatory processes in psychiatric disorders and cardiovascular diseases,shared by heart and brain in the context of stress.