A General Introduction to Glucocorticoid Biology

Immunomodulatory drugs have divergent effects on humoral and cellular immune responses to SARS-CoV-2 vaccination in people living with rheumatoid arthritis

Understanding the efficacy of SARS-CoV-2 vaccination in people on immunosuppressive drugs, including those with rheumatoid arthritis (RA), is critical for their protection. Vaccine induced protection requires antibodies, CD4+ T cells, and CD8+ T cells, but it is unclear if these are equally affected by immunomodulatory drugs. Here, we determined how humoral and cellular SARS-CoV-2 vaccination responses differed between people with RA and controls, and which drug classes impacted these responses. Blood was collected from participants with RA on immunomodulatory drugs and controls after their second, third, and fourth SARS-CoV-2 vaccinations. Receptor binding domain (RBD)-specific antibodies were quantified by ELISA. Spike-specific memory T cells were quantitated using flow cytometry. Linear mixed models assessed the impact of age, sex, and immunomodulatory drug classes on SARS-CoV-2 vaccination responses. Compared to non-RA controls (n = 35), participants with RA on immunomodulatory drugs (n = 62) had lower anti-RBD IgG and spike-specific CD4+ T cell levels, but no deficits in spike-specific CD8+ T cells, following SARS-CoV-2 vaccination. Use of costimulation inhibitors was associated with lower humoral responses. JAK inhibitors were associated with fewer spike-specific CD4+ T cells. Participants with RA on immunomodulatory drugs mounted weaker responses to SARS-CoV-2 vaccination, with different drug classes impacting the cellular and humoral compartments.

Asymmetries of Left and Right Adrenal Glands in Neural Innervation and Glucocorticoids Production

The adrenal gland is paired peripheral end organs of the neuroendocrine system and is responsible for producing crucial stress hormones from its two functional compartments, the adrenal cortex, and the adrenal medulla under stimuli. Left-right asymmetry in vertebrates exists from the central nervous system to peripheral paired endocrine glands. The sided difference in the cerebral cortex is extensively investigated, while the knowledge of asymmetry of paired endocrine glands is still poor. The present study aims to investigate the asymmetries of bilateral adrenal glands, which play important roles in stress adaptation and energy homeostasis via steroid hormones produced from the distinct functional zones. Left and right adrenal glands from male C57BL/6J mice were initially histologically analyzed, and high-throughput RNA sequencing was then used to detect the gene transcriptional difference between left and right adrenal glands. Subsequently, the enrichment of functional pathways and ceRNA regulatory work was validated. The results demonstrated that the left adrenal gland had higher tissue mass and levels of energy expenditure, whereas the right adrenal gland appeared to be more potent in glucocorticoid secretion. Further analysis of adrenal stem/progenitor cell markers predicted that Shh signaling might play an important role in the left-right asymmetry of adrenal glands. Of the hub miRNAs, miRNA-466i-5p was identified in the left-right differential innervation of the adrenal glands. Therefore, the present study provides evidence that there are asymmetries between the left and right adrenal glands in glucocorticoid production and neural innervation, in which Shh signaling and miRNA-466i-5p play an important role.

Monitoring Glucocorticoid Receptor in Plasma-derived Extracellular Vesicles as a Marker of Resistance to Androgen Receptor Signaling Inhibition in Prostate Cancer

Disease progression following androgen ablation was shown to be associated with upregulation of the glucocorticoid receptor (GR). Longitudinal monitoring of GR expression in circulating extracellular vesicles (EV) may reflect changes in the tumor cell and facilitates detection of acquired resistance. We utilized LNCaP, LREX cells and a patient-derived xenograft, MDA PDX 322-2-6a, for in vitro and in vivo experiments. Plasma-derived EVs were isolated from patients with localized high-risk prostate cancer undergoing androgen ablation. The mRNA levels of GR in EVs and their responsive genes were detected by transcriptome analysis, qRT-PCR and the protein levels by Western blot analysis. We detected changes in GR expression at mRNA and protein levels in EVs derived from LNCaP and LREX cells in in vitro studies. In in vivo experiments, LNCaP and the PDX MDA 322-2-6a-bearing mice were treated with enzalutamide. GR levels in plasma-derived EVs were increased only in those tumors that did not respond to enzalutamide. Treatment of mice bearing enzalutamide-resistant tumors with a GR inhibitor in combination with enzalutamide led to a transient pause in tumor growth in a subset of tumors and decreased GR levels intracellular and in plasma-derived EVs. In a subgroup of patients with high-risk localized prostate cancer treated with androgen signaling inhibition, GR was found upregulated in matching tissue and plasma EVs. These analyses showed that GR levels in plasma-derived EVs may be used for monitoring the transition of GR expression allowing for early detection of resistance to androgen ablation treatment.

SIGNIFICANCE

Longitudinal monitoring of GR expression in plasma-derived EVs from patients with prostate cancer treated with androgen signaling inhibitors facilitates early detection of acquisition of resistance to androgen receptor signaling inhibition in individual patients.

Therapeutic Targets and Precision Medicine in COPD: Inflammation, Ion Channels, Both, or Neither?

The development of a wider range of therapeutic options is a key objective in drug discovery for chronic obstructive pulmonary disease (COPD). Fundamental advances in lung biology have the potential to greatly expand the number of therapeutic targets in COPD. The recently reported successful Phase 3 clinical trial of the first biologic agent for COPD, the monoclonal antibody dupilumab, adds additional support to the importance of targeting inflammatory pathways in COPD. However, numerous other cellular mechanisms are important targets in COPD therapeutics, including airway remodeling, the CFTR ion channel, and mucociliary function. Some of these emerging targets can be exploited by the expanded use of existing COPD drugs, such as roflumilast, while targeting others will require the development of novel molecular entities. The identification of additional therapeutic targets and agents has the potential to greatly expand the value of using clinical and biomarker data to classify COPD into specific subsets, each of which can be predictive of an enhanced response to specific subset(s) of targeted therapies. The author reviews established and emerging drug targets in COPD and uses this as a framework to define a novel classification of COPD based on therapeutic targets. This novel classification has the potential to enhance precision medicine in COPD patient care and to accelerate clinical trials and pre-clinical drug discovery efforts.

Harnessing PROTAC technology to combat stress hormone receptor activation

Counteracting the overactivation of glucocorticoid receptors (GR) is an important therapeutic goal in stress-related psychiatry and beyond. The only clinically approved GR antagonist lacks selectivity and induces unwanted side effects. To complement existing tools of small-molecule-based inhibitors, we present a highly potent, catalytically-driven GR degrader, KH-103, based on proteolysis-targeting chimera technology. This selective degrader enables immediate and reversible GR depletion that is independent of genetic manipulation and circumvents transcriptional adaptations to inhibition. KH-103 achieves passive inhibition, preventing agonistic induction of gene expression, and significantly averts the GR's genomic effects compared to two currently available inhibitors. Application in primary-neuron cultures revealed the dependency of a glucocorticoid-induced increase in spontaneous calcium activity on GR. Finally, we present a proof of concept for application in vivo. KH-103 opens opportunities for a more lucid interpretation of GR functions with translational potential.

Maternal depressive symptoms during pregnancy and infant wheezing up to 2 years of age

PURPOSE

To determine whether maternal depressive symptoms at multiple time points during pregnancy are associated with infant wheezing in the first 2 years of life to assess etiologically relevant time windows.

METHODS

We included Dutch women participating in the PRIDE Study with delivery in 2013-2019. Maternal depressive symptoms were assessed with the Hospital Anxiety and Depression Scale and Edinburgh Depression Scale at enrollment and in gestational weeks 17 and 34. The International Study of Asthma and Allergies in Childhood questionnaire was used to assess infant wheezing biannually postpartum. Adjusted risk ratios (RRs) and 95% confidence intervals (CIs) were estimated with modified Poisson regression.

RESULTS

Among 5294 pregnancies included, maternal depressive symptoms in gestational weeks 15-22 was associated with any wheezing in the first 2 years of life (RR 1.36, 95% CI 1.04-1.78) and with current wheezing at 12 (RR 1.29, 95% CI 1.03-1.61) and 18 months (RR 1.33, 1.04-1.69). Depressive symptoms in gestational weeks 32-35 seemed to be associated with any wheezing reported at two years (RR 1.27, 95% CI 0.96-1.69) and current wheezing at 12 months (RR 1.28, 95% CI 1.02-1.60). Four trajectories of depressive symptoms were identified. Only the trajectory with increasing symptoms throughout pregnancy seemed to be associated with infant wheezing (RR 1.36, 95% CI 0.97-1.89).

CONCLUSIONS

Maternal depressive symptoms in mid- and late pregnancy may be associated with development of infant wheezing, particularly those with onset in the second half of pregnancy. Research is needed to identify biological pathways and associations with more objective, long-term respiratory morbidity.

Reduced hydrogen sulfide production contributes to adrenal insufficiency induced by hypoxia via modulation of NLRP3 inflammasome activation

Objective: Adrenocortical responsiveness is critical for maintaining glucocorticoids production and homeostasis during stress. We sought to investigate adrenocortical responsiveness during hypoxia in mice and the mechanisms responsible for the regulation of adrenal responsiveness.Methods: (1) Adult male WT mice were randomly divided into four groups: normoxia, hypoxia (24h), hypoxia (72h), hypoxia (72h) + GYY4137(hydrogen sulfide (H₂S) donor, 133mmol/kg/day); (2) WT mice were randomly divided into four groups: sham, adrenalectomy (ADX), sham+hypoxia, ADX+hypoxia; (3) Cse^-/- mice were randomly divided into two groups: Cse^-/-, Cse^-/- +GYY4137.Results: The circulatory level of corticosteroid induced by ACTH stimulation was significantly reduced in the mice with hypoxia compared with control mice. The mortality rate induced by lipopolysaccharide (LPS) increased during hypoxia. Cystathionine-γ-lyase (CSE) expression was significantly reduced in adrenal glands during hypoxia. GYY4137 treatment significantly increased adrenal responsiveness and attenuated NLRP3 inflammasome activation in mice treated by hypoxia and Cse^-/- mice. Furthermore, The sulfhydrated level of PSMA7 in adrenal gland was decreased in the mice with hypoxia and Cse^-/- mice. PSMA7 was S-sulfhydrated at cysteine 70. Blockage of S-sulfhydration of PSMA7 increased NLRP3 expression in adrenocortical cells.Conclusion: Reduced H₂S production mediated hypo-adrenocortical responsiveness and NLRP3 inflammasome activation via PAMA7 S-sulfhydration during hypoxia.

Intrauterine perfusion of dexamethasone improves pregnancy outcomes in recurrent reproductive failure patients with elevated uterine natural killer cells. A retrospective cohort study

OBJECTIVE

To determine the effect of intrauterine perfusion of dexamethasone (DXM) on pregnancy outcomes in recurrent reproductive failure (RRF) patients with elevated uNK cells.

METHODS

This retrospective cohort study included 132 RRF patients with elevated uNK cells: 56 patients received DXM treatment and 76 patients refused it in the frozen-thawed embryo transfer cycles. To determine the efficacy of intrauterine perfusion of DXM, multivariate logistic regression models and diagnosis-based subgroup analysis were performed. We also compared the pregnancy outcomes of patients with different responsiveness to DXM treatment.

RESULTS

Intrauterine perfusion of DXM significantly improved clinical pregnancy rate (aOR: 3.188, 95% CI: 1.395-7.282, P = .006) and live birth rate (aOR: 3.176, 95% CI: 1.318-7.656, P = .010) in RRF patients with elevated uNK cells, but there was no significant association with miscarriage rate. Subgroup analysis revealed that intrauterine perfusion of DXM in patients with recurrent implantation failure (RIF) showed significant improvement in clinical pregnancy rate (aOR: 6.110, 95% CI: 1.511-24.713, P = .011) and live birth rate (aOR: 9.904, 95% CI: 1.963-49.968, P = .005), but there was insufficient evidence of benefit in recurrent pregnancy loss (RPL) patients. Additionally, uNK cell levels dropped to normal range was achieved in only 35.90% of RRF patients after DXM treatment, no significant difference was found in pregnancy outcomes among patients with different responsiveness to DXM treatment (all P > .05).

CONCLUSION

Intrauterine perfusion of DXM was a promising and effective treatment to enhance clinical pregnancy rate and live birth rate in RRF women with abnormally elevated uNK cells, and RIF patients are more likely to benefit than RPL patients.

Prehospital high-dose methylprednisolone in resuscitated out-of-hospital cardiac arrest patients (STEROHCA): a randomized clinical trial

PURPOSE

Patients who are successfully resuscitated following out-of-hospital cardiac arrest (OHCA) are still at a high risk of neurological damage and death. Inflammation and brain injury are components of the post-cardiac arrest syndrome, and can be assessed by systemic interleukin 6 (IL-6) and neuron-specific enolase (NSE). Anti-inflammatory treatment with methylprednisolone may dampen inflammation, thereby improving outcome. This study aimed to determine if prehospital high-dose methylprednisolone could reduce IL-6 and NSE in comatose OHCA patients.

METHODS

The STEROHCA trial was a randomized, blinded, placebo-controlled, phase II prehospital trial performed at two cardiac arrest centers in Denmark. Resuscitated comatose patients with suspected cardiac etiology were randomly assigned 1:1 to a single intravenous injection of 250 mg methylprednisolone or placebo. The co-primary outcome was reduction of IL-6 and NSE-blood levels measured daily for 72 h from admission. The main secondary outcome was survival at 180 days follow-up.

RESULTS

We randomized 137 patients to methylprednisolone (n = 68) or placebo (n = 69). We found reduced IL-6 levels (p < 0.0001) in the intervention group, with median (interquartile range, IQR) levels at 24 h of 2.1 pg/ml (1.0; 7.1) and 30.7 pg/ml (14.2; 59) in the placebo group. We observed no difference between groups in NSE levels (p = 0.22), with levels at 48 h of 18.8 ug/L (14.4; 24.6) and 14.8 ug/L (11.2; 19.4) in the intervention and placebo group, respectively. In the intervention group, 51 (75%) patients survived and 44 (64%) in the placebo group.

CONCLUSION

Prehospital treatment with high-dose methylprednisolone to resuscitated comatose OHCA patients, resulted in reduced IL-6 levels after 24 h, but did not reduce NSE levels.

The cross-talk between leptin and circadian rhythm signaling proteins in physiological processes: a systematic review

BACKGROUND

Today, modern lifestyles and disrupted sleep patterns cause circadian clock rhythm impairments that are associated with altered leptin levels, which subsequently affect a wide range of physiological processes and have significant health burdens on societies. Nevertheless, there has been no systematic review of circadian clock genes and proteins, leptin, and related signaling pathways.

METHODS

Accordingly, we systematically reviewed circadian clock proteins, leptin, and molecular mechanisms between them by searching Pubmed, Scopus, ProQuest, Web of Sciences, and Google Scholar until September 2022. After considering the inclusion and exclusion criteria, 20 animal studies were selected. The risk of bias was assessed in each study.

RESULTS

The results clarified the reciprocal interconnected relationship between circadian clock genes and leptin. Circadian clock genes regulate leptin expression and signaling via different mechanisms, such as CLOCK-BMAL1 heterodimers, which increase the expression of PPARs. PPARs induce the expression of C/EBPα, a key factor in upregulating leptin expression. CLOCK-BMAL1 also induces the expression of Per1 and Rev-erb genes. PER1 activates mTORC1 and mTORC1 enhances the expression of C/EBPα. In addition, REV-ERBs activate the leptin signaling pathway. Also, leptin controls the expression of circadian clock genes by triggering the AMPK and ERK/MAPK signaling pathways, which regulate the activity of PPARs. Moreover, the roles of these molecular mechanisms are elucidated in different physiological processes and organs.

CONCLUSIONS

Crosstalk between circadian clock genes and leptin and their affecting elements should be considered in the selection of new therapeutic targets for related disorders, especially obesity and metabolic impairments.

NLRP3 inhibitors: Unleashing their therapeutic potential against inflammatory diseases

The NOD-like receptor pyrin domain-containing protein 3 (NLRP3) inflammasome has been linked to the release of pro-inflammatory cytokines and is essential for innate defence against infection and danger signals. These secreted cytokines improve the inflammatory response caused by tissue damage and associated inflammation. Consequently, the development of NLRP3 inflammasome inhibitors are viable option for the treatment of diverse inflammatory disorders. The significant anti-inflammatory effects of the NLRP3 inhibitors have severe side effects. Hence, the application of NLRP3 inhibitors against inflammatory disease has not yet been understood and most of the developed inhibitors are unsuccessful in clinical trials. The processes behind the NLRP3 complex, priming, and activation are the main emphasis of this review, which also covers therapeutical inhibitors of the NLRP3 inflammasome and potential therapeutic strategies for directing the NLRP3 inflammasome towards clinical development.

Influence of dexamethasone on the interaction between glucocorticoid receptor and SOX9: A molecular dynamics study

The glucocorticoid receptor (GR) is a nuclear receptor that controls critical biological processes by regulating the transcription of specific genes. GR transcriptional activity is modulated by a series of ligands and coenzymes, where a ligand can act as an agonist or antagonist. GR agonists, such as the glucocorticoids dexamethasone (DEX) and prednisolone, are widely prescribed to patients with inflammatory and autoimmune diseases. DEX is also used to induce osteogenic differentiation in vitro. Recently, it has been highlighted that DEX induces changes in the osteogenic differentiation of human mesenchymal stromal cells by downregulating the transcription factor SRY-box transcription factor 9 (SOX9) and upregulating the peroxisome proliferator-activated receptor γ (PPARG). SOX9 is fundamental in the control of chondrogenesis, but also in osteogenesis by acting as a dominant-negative of RUNX2. Many processes remain to be clarified during cell fate determination, such as the interplay between the key transcription factors. The main objective pursued by this work is to shed light on the interaction between GR and SOX9 in the presence and absence of DEX at an atomic level of resolution using molecular dynamics simulations. The outcome of this research could help the understanding of possible molecular interactions between GR and SOX9 and their role in the determination of cell fate. The results highlight the key residues at the interface between GR and SOX9 involved in the complexation process and shed light on the mechanism through which DEX modulates GR-SOX9 binding and exerts its biological activity.

The effects of peripheral hormone responses to exercise on adult hippocampal neurogenesis

Over the last decade, a considerable amount of new data have revealed the beneficial effects of exercise on hippocampal neurogenesis and the maintenance or improvement of cognitive function. Investigations with animal models, as well as human studies, have yielded novel understanding of the mechanisms through which endocrine signaling can stimulate neurogenesis, as well as the effects of exercise on acute and/or chronic levels of these circulating hormones. Considering the effects of aging on the decline of specific endocrine factors that affect brain health, insights in this area of research are particularly important. In this review, we discuss how different forms of exercise influence the peripheral production of specific endocrine factors, with particular emphasis on brain-derived neurotrophic factor, growth hormone, insulin-like growth factor-1, ghrelin, estrogen, testosterone, irisin, vascular endothelial growth factor, erythropoietin, and cortisol. We also describe mechanisms through which these endocrine responses to exercise induce cellular changes that increase hippocampal neurogenesis and improve cognitive function.

Corticosteroid-Binding Globulin (SERPINA6) Consolidates Sexual Dimorphism of Adult Rat Liver

Produced by the liver, corticosteroid-binding globulin (CBG) regulates the plasma distribution and actions of glucocorticoids. A sex difference in pituitary growth hormone secretion patterns established during puberty in rats results in increased hepatic CBG production and 2-fold higher plasma corticosterone levels in females. Glucocorticoids control hepatic development and metabolic activities, and we have therefore examined how disrupting the SerpinA6 gene encoding CBG influences plasma corticosterone dynamics, as well as liver gene expression in male and female rats before and after puberty. Comparisons of corticosterone plasma clearance and hepatic uptake in adult rats, with or without CBG, indicated that CBG limits corticosterone clearance by reducing its hepatic uptake. Hepatic transcriptomic profiling revealed minor sex differences (207 differentially expressed genes) and minimal effect of CBG deficiency in 30-day-old rats before puberty. While liver transcriptomes in 60-day-old males lacking CBG remained essentially unchanged, 2710 genes were differentially expressed in wild-type female vs male livers at this age. Importantly, ∼10% of these genes lost their sexually dimorphic expression in adult females lacking CBG, including those related to cholesterol biosynthesis, inflammation, and lipid and amino acid catabolism. Another 203 genes were altered by the loss of CBG specifically in adult females, including those related to xenobiotic metabolism, circadian rhythm, and gluconeogenesis. Our findings reveal that CBG consolidates the sexual dimorphism of the rat liver initiated by sex differences in growth hormone secretion patterns and provide insight into how CBG deficiencies are linked to glucocorticoid-dependent diseases.

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.

Long-term green-Mediterranean diet may favor fasting morning cortisol stress hormone; the DIRECT-PLUS clinical trial

Background

Fasting morning cortisol (FMC) stress hormone levels, are suggested to reflect increased cardiometabolic risk. Acute response to weight loss diet could elevate FMC. Richer Polyphenols and lower carbohydrates diets could favor FMC levels. We aimed to explore the effect of long-term high polyphenol Mediterranean diet (green-MED) on FMC and its relation to metabolic health.

Methods

We randomized 294 participants into one of three dietary interventions for 18-months: healthy dietary guidelines (HDG), Mediterranean (MED) diet, and Green-MED diet. Both MED diets were similarly hypocaloric and lower in carbohydrates and included walnuts (28 g/day). The high-polyphenols/low-meat Green-MED group further included green tea (3-4 cups/day) and a Wolffia-globosa Mankai plant 1-cup green shakeFMC was obtained between 07:00-07:30AM at baseline, six, and eighteen-months.

Results

Participants (age=51.1years, 88% men) had a mean BMI of 31.3kg/m2, FMC=304.07nmol\L, and glycated-hemoglobin-A1c (HbA1c)=5.5%; 11% had type 2 diabetes and 38% were prediabetes. Baseline FMC was higher among men (308.6 ± 90.05nmol\L) than women (269.6± 83.9nmol\L;p=0.02). Higher baseline FMC was directly associated with age, dysglycemia, MRI-assessed visceral adiposity, fasting plasma glucose (FPG), high-sensitivity C-reactive-protein (hsCRP), testosterone, Progesterone and TSH levels (p ≤ 0.05 for all). The 18-month retention was 89%. After 6 months, there were no significant changes in FMC among all intervention groups. However, after 18-months, both MED groups significantly reduced FMC (MED=-1.6%[-21.45 nmol/L]; Green-MED=-1.8%[-26.67 nmol/L]; p<0.05 vs. baseline), as opposed to HDG dieters (+4%[-12 nmol/L], p=0.28 vs. baseline), whereas Green-MED diet FMC change was significant as compared to HDG diet group (p=0.048 multivariable models). Overall, 18-month decrease in FMC levels was associated with favorable changes in FPG, HbA1c, hsCRP, TSH, testosterone and MRI-assessed hepatosteatosis, and with unfavorable changes of HDLc (p<0.05 for all, weight loss adjusted, multivariable models).

Conclusion

Long-term adherence to MED diets, and mainly green-MED/high polyphenols diet, may lower FMC, stress hormone, levels,. Lifestyle-induced FMC decrease may have potential benefits related to cardiometabolic health, irrespective of weight loss.

Clinical trial registration

ClinicalTrials.gov, identifier NCT03020186.

Suppression of mir-150-5p attenuates the anti-inflammatory effect of glucocorticoids in mice with ulcerative colitis

Glucocorticoids have been widely used in the treatment of ulcerative colitis, but not all patients benefit from this therapy due to hormone resistance. Mir-150-5p has been reported to enhance the efficacy of glucocorticoids, and low serum mir-150-5p expression has been linked to glucocorticoid resistance in ulcerative colitis patients. The aim of this study was to elucidate the mechanisms of mir-150-5p regulation on glucocorticoid resistance. An ulcerative colitis mouse model was used to evaluate changes in ulcerative colitis symptoms, inflammatory factors, and glucocorticoid resistance-related gene expression. The results showed that mir-150-5p suppression with antagomirs did not significantly interfere with or enhance the induction of ulcerative colitis symptoms by dextran sulfate sodium, but it did attenuate the inflammation inhibitory effect of dexamethasone by abnormally regulating the expression of IL-17a, IL-10, IL-2 and IL-6 levels and myeloperoxidase activity. Mir-150-5p inhibition also induced a glucocorticoid-resistant gene expression profile in colon tissues of ulcerative colitis mice, with upregulation of p-ERK, p-JNK, and HSP90 and downregulation of p-GRa, FKBP4, and HDAC2 expression. Our results indicate that mir-150-5p suppression attenuates the anti-inflammatory effect of glucocorticoids and may function as a driver element in ulcerative colitis glucocorticoid resistance. AVAILABILITY OF DATA AND MATERIALS: All data and figures analyzed in this study are available from the corresponding author by request.

Postnatal Corticosteroids To Prevent Bronchopulmonary Dysplasia

Bronchopulmonary dysplasia (BPD) is a common, severe chronic respiratory disease that affects very preterm infants. In utero and postnatal exposure to proinflammatory stimuli contribute to the pathophysiology of BPD. Corticosteroids, because of their potent anti-inflammatory properties, may decrease respiratory morbidity and reduce the risk of BPD in very preterm infants. However, these medications can have adverse effects on the developing brain and other organ systems. This review examines current evidence on the risks and benefits of postnatal corticosteroids used to prevent BPD in preterm infants.

Combination therapy using multifunctional dissolvable hyaluronic acid microneedles for oral ulcers

Oral ulcers are common in the oral mucosa. Frequent occurrences of oral ulcers commonly afflict patients, seriously impacting their daily life. Treatments with good anti-inflammatory and antibacterial properties are important for promoting the healing of oral ulcers. In this study, a multifunctional, soluble hyaluronic acid (HA) microneedle (MN) patch was prepared to promote oral ulcer healing. The tip layer of the MN patch was loaded with triamcinolone acetonide (TA) and epidermal growth factor (EGF) to inhibit inflammation and promote angiogenesis. Zeolitic imidazolate framework-8 (ZIF-8) was loaded onto the base layer of the MN patch, which effectively released Zn2+ to mediate antibacterial effects. In addition, HA exerts a protective effect on the mucous membrane. Owing to these properties, the multifunctional MN patches were found to have good anti-inflammatory, antibacterial, and tissue-healing abilities, indicating that the multifunctional MN patch design successfully promoted the healing of oral ulcers.

Sepsis and Adrenal Insufficiency

In sepsis, dysregulation of the hypothalamic-pituitary-adrenal axis, alterations in cortisol metabolism, and tissue resistance to glucocorticoids can all result in relative adrenal insufficiency or critical illness-related corticosteroid insufficiency (CIRCI). The symptoms and signs of CIRCI during sepsis are nonspecific, generally including decreased mental status, unexplained fever, or hypotension refractory to fluids, and the requirement of vasopressor therapy to maintain adequate blood pressure. While we have been aware of this syndrome for over a decade, it remains a poorly understood condition, challenging to diagnose, and associated with significantly diverging practices among clinicians, particularly regarding the optimal dosing and duration of corticosteroid therapy. The existing literature on corticosteroid use in patients with sepsis and septic shock is vast with dozens of randomized controlled trials conducted across the past 4 decades. These studies have universally demonstrated reduced duration of shock, though the effects of corticosteroids on mortality have been inconsistent, and their use has been associated with adverse effects including hyperglycemia, neuromuscular weakness, and an increased risk of infection. In this article, we aim to provide a thorough, evidence-based, and practical review of the current recommendations for the diagnosis and management of patients with sepsis who develop CIRCI, explore the controversies surrounding this topic, and highlight what lies on the horizon as new evidence continues to shape our practice.

Stress aggravates imiquimod-induced psoriasiform inflammation by promoting M1 macrophage polarization

Psychological stress has long been considered to cause the aggravation and recurrence of psoriasis, but the underlying mechanism remains largely unknown. Here, we used a mouse model of restraint-induced stress and imiquimod (IMQ)-induced psoriasiform inflammation to investigate the crosstalk between stress and the skin immune system and their functions in the pathogenesis of psoriasis. We found that stress aggravated skin inflammation and elevated serum corticosterone (CORT) levels in mice. Stress also increased the number of macrophages and glucocorticoid receptor (GR) expression in IMQ-treated mouse skin. GR agonist CORT upregulated the phosphorylation of STAT1 to promote M1 macrophage polarization in vitro. Additionally, GR deletion in macrophages and pharmacologic inhibition of GR improved skin inflammation and reduced M1 macrophage polarization under stress. Taken together, these results indicate that stress aggravates psoriasiform inflammation by promoting CORT/GR signaling-induced M1 macrophage polarization, suggesting that blocking the GR signaling has great potential as an adjuvant treatment for psoriasis patients with chronic stress.

Mitophagy involved the biological processes of hormones

Mitochondria fulfill vital functions in energy production, maintaining ion balance, and facilitating material metabolism. Mitochondria are sacrificed to protect cells or induce apoptosis when the body is under stress. The regulatory pathways of mitophagy include both ubiquitin-dependent and non-dependent pathways. The involvement of mitophagy has been demonstrated in the onset and progression of numerous diseases, highlighting its significant role. Endocrine hormones are chemical substances secreted by endocrine organs or endocrine cells, which participate in the regulation of physiological functions and internal environmental homeostasis of the body. Imbalances in endocrine hormones contribute to the development of various diseases. However, the precise impact of mitophagy on the physiological and pathological processes involving endocrine hormones remains unclear. This article aims to comprehensively overview recent advancements in understanding the mechanisms through which mitophagy regulates endocrine hormones.

Advancing our understanding of the influence of drug induced changes in the gut microbiome on bone health

The gut microbiome has been implicated in a multitude of human diseases, with emerging evidence linking its microbial diversity to osteoporosis. This review article will explore the molecular mechanisms underlying perturbations in the gut microbiome and their influence on osteoporosis incidence in individuals with chronic diseases. The relationship between gut microbiome diversity and bone density is primarily mediated by microbiome-derived metabolites and signaling molecules. Perturbations in the gut microbiome, induced by chronic diseases can alter bacterial diversity and metabolic profiles, leading to changes in gut permeability and systemic release of metabolites. This cascade of events impacts bone mineralization and consequently bone mineral density through immune cell activation. In addition, we will discuss how orally administered medications, including antimicrobial and non-antimicrobial drugs, can exacerbate or, in some cases, treat osteoporosis. Specifically, we will review the mechanisms by which non-antimicrobial drugs disrupt the gut microbiome's diversity, physiology, and signaling, and how these events influence bone density and osteoporosis incidence. This review aims to provide a comprehensive understanding of the complex interplay between orally administered drugs, the gut microbiome, and osteoporosis, offering new insights into potential therapeutic strategies for preserving bone health.

Glucocorticoid-driven mitochondrial damage stimulates Tau pathology

Prolonged exposure to glucocorticoids, the main stress hormones, damages the brain and is a risk factor for depression and Alzheimer's disease. Two major drivers of glucocorticoid-related neurotoxicity are mitochondrial dysfunction and Tau pathology; however, the molecular/cellular mechanisms precipitating these events, and their causal relationship, remain unclear. Using cultured murine hippocampal neurons and 4-5-month-old mice treated with the synthetic glucocorticoid dexamethasone, we investigate the mechanisms underlying glucocorticoid-induced mitochondrial damage and Tau pathology. We find that glucocorticoids stimulate opening of the mitochondrial permeability transition pore via transcriptional upregulation of its activating component, cyclophilin D. Inhibition of cyclophilin D is protective against glucocorticoid-induced mitochondrial damage as well as Tau phosphorylation and oligomerization in cultured neurons. We further identify the mitochondrially-targeted compound mito-apocynin as an inhibitor of glucocorticoid-induced permeability transition pore opening, and show that this compound protects against mitochondrial dysfunction, Tau pathology, synaptic loss, and behavioural deficits induced by glucocorticoids in vivo. Finally, we demonstrate that mito-apocynin and the glucocorticoid receptor antagonist mifepristone rescue Tau pathology in cytoplasmic hybrid cells, an ex vivo Alzheimer's disease model wherein endogenous mitochondria are replaced with mitochondria from Alzheimer's subjects. These findings show that mitochondrial permeability transition pore opening is a precipitating factor in glucocorticoid-induced mitochondrial dysfunction, and that this event stimulates Tau pathogenesis. Our data also link glucocorticoids to mitochondrial dysfunction and Tau pathology in the context of Alzheimer's disease and suggest that mitochondria are promising therapeutic targets for mitigating stress- and Tau-related brain damage.

Development and validation of a simple method for the determination of triamcinolone acetonide in nasal spray

A rapid, convenient, and sensitive analytical technique for quantitative analysis of triamcinolone acetonide (TAC) in pharmaceutical nasal spray dosage form using the blue tetrazolium colorimetric reaction and UV spectrophotometric method was developed and validated. Beer's law of the developed method was proven in the concentration range of 10-40 µg/mL and showed a specific linear relationship with coefficient value R2 = 0.998. The LOQ level was 9.99 µg/mL, with (RSD = 0.26%). From precision assay, RSD values have been obtained for the repeatability and intermediate precision, which were found to be (RSD = 1.65%) and (RSD = 2.01%), respectively, indicating that the method is reproducible. Recovery studies showed mean recoveries in the range of (100.08-103.65 %), meeting the acceptance criteria for accuracy. In addition, we compared the results of the developed method UV-Vis spectrophotometric procedure with those of a well-established official USP analytical procedure (HPLC), and the results showed good agreement. The proposed UV method represents a potential alternative to the official USP analytical assay procedure (HPLC) for estimating TAC in nasal spray forms. Furthermore, it has the potential to be implemented in routine use for rapid qualitative and quantitative determinations for TAC.

Changes in environmental stress over COVID-19 pandemic likely contributed to failure to replicate adiposity phenotype associated with Krtcap3

We previously identified keratinocyte-associated protein 3, Krtcap3, as an obesity-related gene in female rats where a whole body Krtcap3 knockout (KO) led to increased adiposity compared to wild-type (WT) controls when fed a high-fat diet (HFD). We sought to replicate this work to better understand the function of Krtcap3 but were unable to reproduce the adiposity phenotype. In the current work, WT female rats ate more compared to WT in the prior study, with corresponding increases in body weight and fat mass, while there were no changes in these measures in KO females between the studies. The prior study was conducted before the COVID-19 pandemic, while the current study started after initial lockdown orders and was completed during the pandemic in a generally less stressful environment. We hypothesize that the environmental changes impacted stress levels and may explain the failure to replicate our results. Analysis of corticosterone (CORT) at euthanasia showed a significant study-by-genotype interaction where WT had significantly higher CORT relative to KO in study 1, with no differences in study 2. These data suggest that decreasing Krtcap3 expression may alter the environmental stress response to influence adiposity. We also found that KO rats in both studies, but not WT, experienced a dramatic increase in CORT after their cage mate was removed, suggesting a separate connection to social behavioral stress. Future work is necessary to confirm and elucidate the finer mechanisms of these relationships, but these data indicate the possibility of Krtcap3 as a novel stress gene.NEW & NOTEWORTHY Obesity is linked to both genetics and environmental factors such as stress. Krtcap3 has previously been identified as a gene associated with adiposity, and our work here demonstrates that environmental stress may influence the role of Krtcap3 on both food intake and adiposity. Obesity is strongly influenced by stress in humans, so the identification of novel genes that link stress and obesity will greatly advance our understanding of the disease.

Exogenous corticosterone administration during pregnancy in mice alters placental and fetal thyroid hormone availability in females

INTRODUCTION

Maternal prenatal psychological stress is associated with adverse pregnancy outcomes and increased risk of adverse health outcomes in children. While the molecular mechanisms that govern these associations has not been fully teased apart, stress-induced changes in placental function can drive sex-specific phenotypes in offspring. We sought to identify and examine molecular pathways in the placenta that are altered in response to maternal prenatal stress.

METHODS

We previously employed a mouse model of maternal prenatal stress where pregnant dams were treated with stress hormone (CORT) beginning in mid-gestation. Using this model, we conducted RNAseq analysis of whole placenta at E18.5. We used qRT-PCR to validate gene expression changes in the placenta and in a trophoblast cell line. ELISAs were used to measure the abundance of thyroid hormones in maternal and fetal serum and in the placenta.

RESULTS

Dio2 was amongst the top differentially expressed genes in response to exogenous stress hormone. Dio2 expression was more downregulated in placenta of female fetuses from CORT-treated dams than both control placenta from females and placenta from male fetuses. Consistent with Dio2's role in production of bioactive thyroid hormone (T3), we found that there was a reduction of T3 in placenta and serum of female embryos from CORT-treated dams at E18.5. Both T3 and T4 were reduced in the fetal compartment of the placenta of female fetuses from CORT-treated dams at E16.5. Exogenous stress hormone induced reduction in thyroid hormone in females was independent of circulating levels of TH in the dams.

DISCUSSION

The placental thyroid hormone synthesis pathway may be a target of elevated maternal stress hormone and modulate fetal programming of health and disease of offspring in a sex-specific fashion.

Dexamethasone protects against Aspergillus fumigatus-induced severe asthma via modulating pulmonary immunometabolism

Severe asthma is a difficult-to-treat chronic airway inflammatory disease requiring systemic corticosteroids to achieve asthma control. It has recently been shown that drugs targeting immunometabolism have elicited anti-inflammatory effects. The purpose of this study was to investigate potential immunometabolic modulatory actions of systemic dexamethasone (Dex) in an Aspergillus fumigatus (Af)-induced severe asthma model. Mice were repeatedly exposed to the Af aeroallergen before systemic treatment with Dex. Simultaneous measurements of airway inflammation, real-time glycolytic and oxidative phosphorylation (OXPHOS) activities, expression levels of key metabolic enzymes, and amounts of metabolites were studied in lung tissues, and in primary alveolar macrophages (AMs) and eosinophils. Dex markedly reduced Af-induced eosinophilic airway inflammation, which was coupled with an overall reduction in lung glycolysis, glutaminolysis, and fatty acid synthesis. The anti-inflammatory effects of Dex may stem from its immunometabolic actions by downregulating key metabolic enzymes including pyruvate dehydrogenase kinase, glutaminase, and fatty acid synthase. Substantial suppression of eosinophilic airway inflammation by Dex coincided with a specific escalation of mitochondrial proton leak in primary lung eosinophils. Besides, while our findings confirmed that inflammation corresponds with an upregulation of glycolysis, it was accompanied with an unexpectedly stable or elevated OXPHOS in the lungs and activated immune cells, respectively. Our findings reveal that the anti-inflammatory effects of Dex in severe asthma are associated with downregulation of pyruvate dehydrogenase kinase, glutaminase, and fatty acid synthase, and the augmentation of mitochondrial proton leak in lung eosinophils. These enzymes and biological processes may be valuable targets for therapeutic interventions against severe asthma.

Tramadol/paracetamol treatment attenuates the development of collagen antibody-induced arthritis and interferes with prednisolone treatment in mice

The collagen antibody-induced arthritis (CAIA) model is highly effective in inducing arthritis, making it an attractive model for screening therapeutic compounds such as glucocorticoids (GCs). The severity of discomfort in this model makes it desirable to administer analgesics, but it is a prerequisite that these do not interfere with the model or tested therapeutics. In the present study, we studied the effect of 1 mg/mL tramadol and 3.5 mg/mL paracetamol (TP) on CAIA in male BALB/cAnNCrl mice and the possible interference of TP analgesia with the activity of the GC drug prednisolone (Pred). Our results showed that TP abolished the Pred-induced amelioration of CAIA, as well as several other Pred-induced effects, such as the reduction in thymus weight and the increase in insulin level. This most likely results from the effects of TP on the hepatic metabolism of this drug, since it strongly increased the Cyp3a11 expression in the liver. Altogether, we conclude that TP analgesia is not suitable for the CAIA model in male BALB/cAnNCrl mice, in particular when evaluating the effects of GCs such as Pred.

Glucocorticoids Impair the 7α-Hydroxycholesterol-Enhanced Innate Immune Response

Glucocorticoids suppress the vascular inflammation that occurs under hypercholesterolemia, as demonstrated in an animal model fed a high-cholesterol diet. However, the molecular mechanisms underlying these beneficial effects remain poorly understood. Because cholesterol is oxidized to form cholesterol oxides (oxysterols) that are capable of inducing inflammation, we investigated whether glucocorticoids affect the immune responses evoked by 7α-hydroxycholesterol (7αOHChol). The treatment of human THP-1 monocytic cells with dexamethasone (Dex) and prednisolone (Pdn) downregulated the expression of pattern recognition receptors (PRRs), such as TLR6 and CD14, and diminished 7αOHChol-enhanced response to FSL-1, a TLR2/6 ligand, and lipopolysaccharide, which interacts with CD14 to initiate immune responses, as determined by the reduced secretion of IL-23 and CCL2, respectively. Glucocorticoids weakened the 7αOHChol-induced production of CCL2 and CCR5 ligands, which was accompanied by decreased migration of monocytic cells and CCR5-expressing Jurkat T cells. Treatment with Dex or Pdn also reduced the phosphorylation of the Akt-1 Src, ERK1/2, and p65 subunits. These results indicate that both Dex and Pdn impair the expression of PRRs and their downstream products, chemokine production, and phosphorylation of signaling molecules. Collectively, glucocorticoids suppress the innate immune response and activation of monocytic cells to an inflammatory phenotype enhanced or induced by 7αOHChol, which may contribute to the anti-inflammatory effects in hypercholesterolemic conditions.

Interplay between inflammatory bowel disease therapeutics and the gut microbiome reveals opportunities for novel treatment approaches

Inflammatory bowel disease (IBD) is a complex heterogeneous disorder defined by recurring chronic inflammation of the gastrointestinal tract, attributed to a combination of factors including genetic susceptibility, altered immune response, a shift in microbial composition/microbial insults (infection/exposure), and environmental influences. Therapeutics generally used to treat IBD mainly focus on the immune response and include non-specific anti-inflammatory and immunosuppressive therapeutics and targeted therapeutics aimed at specific components of the immune system. Other therapies include exclusive enteral nutrition and emerging stem cell therapies. However, in recent years, scientists have begun to examine the interplay between these therapeutics and the gut microbiome, and we present this information here. Many of these therapeutics are associated with alterations to gut microbiome composition and functionality, often driving it toward a "healthier profile" and preclinical studies have revealed that such alterations can play an important role in therapeutic efficacy. The gut microbiome can also improve or hinder IBD therapeutic efficacy or generate undesirable metabolites. For certain IBD therapeutics, the microbiome composition, particularly before treatment, may serve as a biomarker of therapeutic efficacy. Utilising this information and manipulating the interactions between the gut microbiome and IBD therapeutics may enhance treatment outcomes in the future and bring about new opportunities for personalised, precision medicine.

Adipocyte Glucocorticoid Receptor Inhibits Immune Regulatory Genes to Maintain Immune Cell Homeostasis in Adipose Tissue

Glucocorticoids acting via the glucocorticoid receptors (GR) are key regulators of metabolism and the stress response. However, uncontrolled or excessive GR signaling adversely affects adipose tissue, including endocrine, immune, and metabolic functions. Inflammation of the adipose tissue promotes systemic metabolic dysfunction; however, the molecular mechanisms underlying the role of adipocyte GR in regulating genes associated with adipose tissue inflammation are poorly understood. We performed in vivo studies using adipocyte-specific GR knockout mice in conjunction with in vitro studies to understand the contribution of adipocyte GR in regulating adipose tissue immune homeostasis. Our findings show that adipocyte-specific GR signaling regulates adipokines at both mRNA and plasma levels and immune regulatory (Coch, Pdcd1, Cemip, and Cxcr2) mRNA gene expression, which affects myeloid immune cell presence in white adipose tissue. We found that, in adipocytes, GR directly influences Cxcr2. This chemokine receptor promotes immune cell migration, indirectly affecting Pdcd1 and Cemip gene expression in nonadipocyte or stromal cells. Our findings suggest that GR adipocyte signaling suppresses inflammatory signals, maintaining immune homeostasis. We also found that GR signaling in adipose tissue in response to stress is sexually dimorphic. Understanding the molecular relationship between GR signaling and adipose tissue inflammation could help develop potential targets to improve local and systemic inflammation, insulin sensitivity, and metabolic health.

Screening of Anti-Inflammatory Activity and Metabolomics Analysis of Endophytic Fungal Extracts; Identification and Characterization of Perylenequinones and Terpenoids from the Interesting Active Alternaria Endophyte

Patients suffering from inflammatory chronic diseases are classically treated with anti-inflammatory drugs but unfortunately are highly susceptible to becoming resistant to their treatment. Finding new drugs is therefore crucial and urgent and research on endophytic fungi is a promising way forward. Endophytic fungi are microorganisms that colonize healthy plants and live within their intercellular tissues. They are able to produce a large variety of secondary metabolites while allowing their host to stay healthy. A number of these molecules are endowed with antioxidant or antimicrobial as well as cytotoxic properties, making them very interesting/promising in the field of human therapy. The aim of our study was to investigate whether extracts from five endophytic fungi isolated from plants are endowed with anti-inflammatory activity. Extracts of the endophytic fungi Alternaria alternata from Calotropis procera leaves and Aspergillus terreus from Trigonella foenum-graecum seeds were able to counteract the lipopolysaccharide (LPS) pro-inflammatory effect on THP-1 cells differentiated into macrophages. Moreover, they were able to induce an anti-inflammatory state, rendering them less sensitive to the LPS pro-inflammatory stimulus. Taken together, these results show that these both endophytic fungi could be interesting alternatives to conventional anti-inflammatory drugs. To gain more detailed knowledge of their chemical richness, phytochemical analysis of the ethyl acetate extracts of the five endophytic fungi studied was performed using HPTLC, GC-MS and LC-MS with the Global Natural Products Social (GNPS) platform and the MolNetEnhancer tool. A large family of metabolites (carboxylic acids and derivatives, steroid derivatives, alkaloids, hydroxyanthraquinones, valerolactones and perylenequinones) were detected. The purification of endophytic fungus extract of Alternaria alternate, which diminished TNF-α production of 66% at 20 µg/mL, incubated one hour before LPS addition, led to the characterization of eight pure compounds. These molecules are altertoxins I, II, III, tricycloalternarenes 3a, 1b, 2b, anthranilic acid, and o-acetamidobenzoic acid. In the future, all these pure compounds will be evaluated for their anti-inflammatory activity, while altertoxin II has been shown in the literature as the most active mycotoxin in terms of anti-inflammatory activity.

Biased regulation of glucocorticoid receptors signaling

Glucocorticoids (GCs), steroid hormones that depend on glucocorticoid receptor (GR) binding for their action, are essential for regulating numerous homeostatic functions in the body.GR signals are biased, that is, GR signals are various in different tissue cells, disease states and ligands. This biased regulation of GR signaling appears to depend on ligand-induced metameric regulation, protein post-translational modifications, assembly at response elements, context-specific assembly (recruitment of co-regulators) and intercellular differences. Based on the bias regulation of GR, selective GR agonists and modulators (SEGRAMs) were developed to bias therapeutic outcomes toward expected outcomes (e.g., anti-inflammation and immunoregulation) by influencing GR-mediated gene expression. This paper provides a review of the bias regulation and mechanism of GR and the research progress of drugs.

Enhancement of muscarinic receptor-mediated excitation in spontaneously hypertensive rat adrenal medullary chromaffin cells

One of the mechanisms for hypertension is an increase in blood catecholamines due to increased secretion from sympathetic nerve terminals and adrenal medullary chromaffin (AMC) cells. Spontaneously hypertensive rats (SHRs) are used as an animal model of hypertension. Catecholamine secretion in AMC cells occurs in response to humoral factors and neuronal inputs from the sympathetic nerve fibres. Acetylcholine (ACh) released from the nerve terminals activates nicotinic as well as muscarinic ACh receptors. The present experiment aimed to elucidate whether muscarinic receptor-mediated excitation is altered in SHR AMC cells and, if it is, how. Compared with normotensive rat AMC cells, muscarinic stimulation induced greater catecholamine secretion and larger depolarising inward currents in SHR AMC cells. In contrast to normotensive rat AMC cells, the muscarine-induced current consisted of quinine-sensitive and quinine-insensitive components. The former and the latter are possibly ascribed to nonselective cation channel activation and TWIK-related acid-sensitive K+ (TASK) channel inhibition, as noted in guinea pig AMC cells. In fact, immunoreactive material for TASK1 and several isoforms of transient receptor potential canonical (TRPC) channels was detected in SHR AMC cells. Stromal interaction molecule 1 (STIM1), which plays an essential role for heteromeric TRPC1-TRPC4 channel formation and is not expressed in normotensive rat AMC cells, was detected in the cytoplasm and co-localised with TRPC1. The expression of muscarinic M1 receptors was enhanced in SHR AMC cells compared with normotensive rats. The results indicate that muscarinic excitation is enhanced in SHR AMC cells, probably through facilitation of TRPC channel signalling.

Stabilizing the neural barrier - A novel approach in pain therapy

Chronic and neuropathic pain are a widespread burden. Incomplete understanding of underlying pathomechanisms is one crucial factor for insufficient treatment. Recently, impairment of the blood nerve barrier (BNB) has emerged as one key aspect of pain initiation and maintenance. In this narrative review, we discuss several mechanisms and putative targets for novel treatment strategies. Cells such as pericytes, local mediators like netrin-1 and specialized proresolving mediators (SPMs), will be covered as well as circulating factors including the hormones cortisol and oestrogen and microRNAs. They are crucial in either the BNB or similar barriers and associated with pain. While clinical studies are still scarce, these findings might provide valuable insight into mechanisms and nurture development of therapeutic approaches.

Nlrp3 Deficiency Alleviates Lipopolysaccharide-Induced Acute Kidney Injury via Suppressing Renal Inflammation and Ferroptosis in Mice

The nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) inflammasome is a vital component of many inflammatory responses. Here, we intended to investigate the involvement of NLRP3 in lipopolysaccharide (LPS)-induced sepsis-associated acute kidney injury (S-AKI) and explore its mechanisms. For the first time, we validated elevated NLRP3 expression in the renal tissues of S-AKI patients by immunohistochemistry analysis. Through LPS injection in both wild-type and Nlrp3-/- mice, a S-AKI model was developed. It was found that LPS-induced kidney injury, including an abnormal morphology in a histological examination, abnormal renal function in a laboratory examination, and an increase in the expression of AKI biomarkers, was dramatically reversed in Nlrp3-deficient mice. Nlrp3 deletion alleviated renal inflammation, as evidenced by the suppression of the expression of pro-inflammatory cytokines and chemokines. A combinative analysis of RNA sequencing and the FerrDb V2 database showed that Nlrp3 knockout regulated multiple metabolism pathways and ferroptosis in LPS-induced S-AKI. Further qPCR coupled with Prussian blue staining demonstrated that Nlrp3 knockout inhibited murine renal ferroptosis, indicating a novel mechanism involving S-AKI pathogenesis by NLRP3. Altogether, the aforementioned findings suggest that Nlrp3 deficiency alleviates LPS-induced S-AKI by reducing renal inflammation and ferroptosis. Our data highlight that NLRP3 is a potential therapeutic target for S-AKI.

Sex Differences in Therapies against Myocardial Ischemia-Reperfusion Injury: From Basic Science to Clinical Perspectives

Mortality from myocardial infarction (MI) has declined over recent decades, which could be attributed in large part to improved treatment methods. Early reperfusion is the cornerstone of current MI treatment. However, reoxygenation via restored blood flow induces further damage to the myocardium, leading to ischemia-reperfusion injury (IRI). While experimental studies overwhelmingly demonstrate that females experience greater functional recovery from MI and decreased severity in the underlying pathophysiological mechanisms, the outcomes of MI with subsequent reperfusion therapy, which is the clinical correlate of myocardial IRI, are generally poorer for women compared with men. Distressingly, women are also reported to benefit less from current guideline-based therapies compared with men. These seemingly contradicting outcomes between experimental and clinical studies show a need for further investigation of sex-based differences in disease pathophysiology, treatment response, and a sex-specific approach in the development of novel therapeutic methods against myocardial IRI. In this literature review, we summarize the current knowledge on sex differences in the underlying pathophysiological mechanisms of myocardial IRI, including the roles of sex hormones and sex chromosomes. Furthermore, we address sex differences in pharmacokinetics, pharmacodynamics, and pharmacogenetics of current drugs prescribed to limit myocardial IRI. Lastly, we highlight ongoing clinical trials assessing novel pharmacological treatments against myocardial IRI and sex differences that may underlie the efficacy of these new therapeutic approaches.

Crosstalk between glucocorticoid and mineralocorticoid receptors boosts glucocorticoid-induced killing of multiple myeloma cells

The glucocorticoid receptor (GR) is a crucial drug target in multiple myeloma as its activation with glucocorticoids effectively triggers myeloma cell death. However, as high-dose glucocorticoids are also associated with deleterious side effects, novel approaches are urgently needed to improve GR action in myeloma. Here, we reveal a functional crosstalk between GR and the mineralocorticoid receptor (MR) that plays a role in improved myeloma cell killing. We show that the GR agonist dexamethasone (Dex) downregulates MR levels in a GR-dependent way in myeloma cells. Co-treatment of Dex with the MR antagonist spironolactone (Spi) enhances Dex-induced cell killing in primary, newly diagnosed GC-sensitive myeloma cells. In a relapsed GC-resistant setting, Spi alone induces distinct myeloma cell killing. On a mechanistic level, we find that a GR-MR crosstalk likely arises from an endogenous interaction between GR and MR in myeloma cells. Quantitative dimerization assays show that Spi reduces Dex-induced GR-MR heterodimerization and completely abolishes Dex-induced MR-MR homodimerization, while leaving GR-GR homodimerization intact. Unbiased transcriptomics analyses reveal that c-myc and many of its target genes are downregulated most by combined Dex-Spi treatment. Proteomics analyses further identify that several metabolic hallmarks are modulated most by this combination treatment. Finally, we identified a subset of Dex-Spi downregulated genes and proteins that may predict prognosis in the CoMMpass myeloma patient cohort. Our study demonstrates that GR-MR crosstalk is therapeutically relevant in myeloma as it provides novel strategies for glucocorticoid-based dose-reduction.

Exogenous corticosterone administration during pregnancy alters placental and fetal thyroid hormone availability in females

Introduction

Maternal prenatal stress is associated with adverse pregnancy outcomes and predisposition to long-term adverse health outcomes in children. While the molecular mechanisms that govern these associations has not been fully teased apart, stress-induced changes in placental function can drive sex-specific phenotypes in offspring. We sought to identify and examine molecular pathways in the placenta that are altered in response to maternal prenatal stress.

Methods

Using a mouse model of maternal prenatal stress, we conducted RNA-seq analysis of whole placenta at E18.5. We used qRT-PCR to validate gene expression changes in the placenta and in a trophoblast cell line. ELISAs were used to measure the abundance of thyroid hormones in maternal and fetal serum and in the placenta.

Results

Dio2 was amongst the top differentially expressed genes in response to elevated maternal stress hormone. Dio2 expression was more downregulated in female placenta from stressed dams than both female control and male placenta. Consistent with Dio2's role in production of bioactive thyroid hormone (T3), we found that there was a reduction of T3 in placenta and serum of female embryos from stressed dams at E18.5. Both T3 and T4 were reduced in the fetal compartment of the female placenta from stressed dams at E16.5. Stress hormone induced reduction in thyroid hormone in females was independent of circulating levels of TH in the dams.

Discussion

The placental thyroid hormone synthesis pathway may be a target of maternal stress and modulate fetal programming of health and disease of offspring in a sex-specific fashion.

Glucocorticoids and Their Receptor Isoforms: Roles in Female Reproduction, Pregnancy, and Foetal Development

Alterations in the hypothalamic-pituitary-adrenal (HPA) axis and associated changes in circulating levels of glucocorticoids are integral to an organism's response to stressful stimuli. Glucocorticoids acting via glucocorticoid receptors (GRs) play a role in fertility, reproduction, placental function, and foetal development. GRs are ubiquitously expressed throughout the female reproductive system and regulate normal reproductive function. Stress-induced glucocorticoids have been shown to inhibit reproduction and affect female gonadal function by suppressing the hypothalamic-pituitary-gonadal (HPG) axis at each level. Furthermore, during pregnancy, a mother's exposure to prenatal stress or external glucocorticoids can result in long-lasting alterations to the foetal HPA and neuroendocrine function. Several GR isoforms generated via alternative splicing or translation initiation from the GR gene have been identified in the mammalian ovary and uterus. The GR isoforms identified include the splice variants, GRα and GRβ, and GRγ and GR-P. Glucocorticoids can exert both stimulatory and inhibitory effects and both pro- and anti-inflammatory functions in the ovary, in vitro. In the placenta, thirteen GR isoforms have been identified in humans, guinea pigs, sheep, rats, and mice, indicating they are conserved across species and may be important in mediating a differential response to stress. Distinctive responses to glucocorticoids, differential birth outcomes in pregnancy complications, and sex-based variations in the response to stress could all potentially be dependent on a particular GR expression pattern. This comprehensive review provides an overview of the structure and function of the GR in relation to female fertility and reproduction and discusses the changes in the GR and glucocorticoid signalling during pregnancy. To generate this overview, an extensive non-systematic literature search was conducted across multiple databases, including PubMed, Web of Science, and Google Scholar, with a focus on original research articles, meta-analyses, and previous review papers addressing the subject. This review integrates the current understanding of GR variants and their roles in glucocorticoid signalling, reproduction, placental function, and foetal growth.

Accumulation and glucocorticoid signaling suppression by four emerging perfluoroethercarboxylic acids based on animal exposure and cell testing

Various perfluoroethercarboxylic acids (PFECA) have emerged as next-generation replacements of legacy per- and polyfluoroalkyl substances (PFAS). However, there is a paucity of information regarding their bioaccumulation ability and hazard characterization. Here, we explored the accumulation and hepatotoxicity of four PFECA compounds (HFPO-DA, HFPO-TA, PFO4DA, and PFO5DoDA) in comparison to perfluorooctanoic acid (PFOA) after chronic low-dose exposure in mice. Except for HFPO-DA, the levels of all tested PFAS in the liver exceeded that in serum. High molecular weight PFECA compounds (PFO5DoDA and HFPO-TA) showed stronger accumulation capacity and longer half-lives (t1/2) than low molecular weight PFECA compounds (HFPO-DA and PFO4DA) and even legacy PFOA. Although hepatomegaly is a common apical end point of PFAS exposure, the differentially expressed gene (DEG) profiles in the liver suggested significant differences between PFOA and the four PFECA compounds. Gene enrichment analysis supported a considerable inhibitory effect of PFECA, but not PFOA, on the glucocorticoid receptor (GR) signaling pathway. Both HFPO-TA and PFO5DoDA demonstrated a more pronounced ability to perturb RNA expression profiles in vivo and to suppress GR signaling in vitro compared to HFPO-DA and PFO4DA. Calculated reference doses (RfDs) emphasized the potential hazard of PFECA to human health. Overall, our findings indicate that PFECA alternatives do not ease the concerns raised from legacy PFAS pollution.

Endocrine disorders associated with obesity

Several endocrine disorders, including diabetes, insulinoma, Cushing syndrome, hypothyroidism, polycystic ovarian syndrome, and growth hormone deficiency, are associated with obesity. The mechanisms underlying the development of obesity vary according to the abnormalities of endocrine function. The primary actions of insulin, glucocorticoids (GCs), thyroid hormone, and growth hormone are associated with energy metabolism in the liver, muscle, adipose tissue, and other tissues. This chapter describes the pathogenesis of obesity and metabolic dysfunction associated with excess insulin or GCs and the deficiency of thyroid hormone or growth hormone.

Glucocorticoid Treatment in Acute Respiratory Distress Syndrome: An Overview on Mechanistic Insights and Clinical Benefit

Acute lung injury/acute respiratory distress syndrome (ALI/ARDS), triggered by various pathogenic factors inside and outside the lungs, leads to diffuse lung injury and can result in respiratory failure and death, which are typical clinical critical emergencies. Severe acute pancreatitis (SAP), which has a poor clinical prognosis, is one of the most common diseases that induces ARDS. When SAP causes the body to produce a storm of inflammatory factors and even causes sepsis, clinicians will face a two-way choice between anti-inflammatory and anti-infection objectives while considering the damaged intestinal barrier and respiratory failure, which undoubtedly increases the difficulty of the diagnosis and treatment of SAP-ALI/ARDS. For a long time, many studies have been devoted to applying glucocorticoids (GCs) to control the inflammatory response and prevent and treat sepsis and ALI/ARDS. However, the specific mechanism is not precise, the clinical efficacy is uneven, and the corresponding side effects are endless. This review discusses the mechanism of action, current clinical application status, effectiveness assessment, and side effects of GCs in the treatment of ALI/ARDS (especially the subtype caused by SAP).

Exploring the Potential of Aptamers in Targeting Neuroinflammation and Neurodegenerative Disorders: Opportunities and Challenges

Neuroinflammation is the precursor for several neurodegenerative diseases (NDDs), such as Alzheimer's disease (AD), Parkinson's disease (PD), and multiple sclerosis (MS). Targeting neuroinflammation has emerged as a promising strategy to address a wide range of CNS pathologies. These NDDs still present significant challenges in terms of limited and ineffective diagnosis and treatment options, driving the need to explore innovative and novel therapeutic alternatives. Aptamers are single-stranded nucleic acids that offer the potential for addressing these challenges through diagnostic and therapeutic applications. In this review, we summarize diagnostic and therapeutic aptamers for inflammatory biomolecules, as well as the inflammatory cells in NDDs. We also discussed the potential of short nucleotides for Aptamer-Based Targeted Brain Delivery through their unique features and modifications, as well as their ability to penetrate the blood-brain barrier. Moreover, the unprecedented opportunities and substantial challenges of using aptamers as therapeutic agents, such as drug efficacy, safety considerations, and pharmacokinetics, are also discussed. Taken together, this review assesses the potential of aptamers as a pioneering approach for target delivery to the CNS and the treatment of neuroinflammation and NDDs.

Budesonide Analogues Preserve Stem Cell Pluripotency and Delay 3D Gastruloid Development

Small molecules that can modulate or stabilize cell-cell interactions are valuable tools for investigating the impact of collective cell behavior on various biological processes such as development/morphogenesis, tissue regeneration and cancer progression. Recently, we showed that budesonide, a glucocorticoid widely used as an anti-asthmatic drug, is a potent regulator of stem cell pluripotency. Here we tested the effect of different budesonide derivatives and identified CHD-030498 as a more effective analogue of budesonide. CHD-030498 was able to prevent stem cell pluripotency exit in different cell-based models, including embryonic stem-to-mesenchymal transition, spontaneous differentiation and 3D gastruloid development, and at lower doses compared to budesonide.

Comparison of the gut microbiota and metabolites between Diannan small ear pigs and Diqing Tibetan pigs

Objective

Host genetics and environment participate in the shaping of gut microbiota. Diannan small ear pigs and Diqing Tibetan pigs are excellent native pig breeds in China and live in different environments. However, the gut microbiota of Diannan small ear pigs and Diqing Tibetan pigs were still rarely understood. Therefore, this study aimed to analyze the composition characteristics of gut microbiota and metabolites in Diannan small ear pigs and Diqing Tibetan pigs.

Methods

Fresh feces of 6 pigs were randomly collected from 20 4-month-old Diannan small ear pigs (DA group) and 20 4-month-old Diqing Tibetan pigs (TA group) for high-throughput 16S rRNA sequencing and liquid chromatography-mass spectrometry (LC-MS) non-targeted metabolome analysis.

Results

The results revealed that Firmicutes and Bacteroidetes were the dominant phyla in the two groups. Chao1 and ACE indices differed substantially between DA and TA groups. Compared with the DA group, the relative abundance of Prevotellaceae, and Ruminococcus was significantly enriched in the TA group, while the relative abundance of Lachnospiraceae, Actinomyces, and Butyricicoccus was significantly reduced. Cholecalciferol, 5-dehydroepisterol, stigmasterol, adrenic acid, and docosahexaenoic acid were significantly enriched in DA group, which was involved in the steroid biosynthesis and biosynthesis of unsaturated fatty acids. 3-phenylpropanoic acid, L-tyrosine, phedrine, rhizoctin B, and rhizoctin D were significantly enriched in TA group, which was involved in the phenylalanine metabolism and phosphonate and phosphinate metabolism.

Conclusion

We found that significant differences in gut microbiota composition and metabolite between Diannan small ear pigs and Diqing Tibetan pigs, which provide a theoretical basis for exploring the relationship between gut microbiota and pig breeds.

Glucocorticoids Accelerate Erythropoiesis in Healthy Humans-Should the Use in Sports Be Reevaluated?

PURPOSE

The World Anti-Doping Agency prohibits glucocorticoid administration in competition but not in periods out of competition. Glucocorticoid usage is controversial as it may improve performance, albeit debated. A hitherto undescribed but performance-relevant effect of glucocorticoids in healthy humans is accelerated erythropoiesis. We investigated whether a glucocorticoid injection accelerates erythropoiesis, increases total hemoglobin mass, and improves exercise performance.

METHODS

In a counterbalanced, randomized, double-blinded, placebo-controlled crossover design (3 months washout), 10 well-trained males (peak oxygen uptake, 60 ± 3 mL O 2 ·min -1 ·kg -1 ) were injected with 40 mg triamcinolone acetonide (glucocorticoid group) or saline (placebo group) in the gluteal muscles. Venous blood samples collected before and 7-10 h, 1, 3, 7, 14, and 21 d after treatment were analyzed for hemoglobin concentration and reticulocyte percentage. Hemoglobin mass and mean power output in a 450-kcal time trial were measured before as well as 1 and 3 wk after treatment.

RESULTS

A higher reticulocyte percentage was evident 3 d (19% ± 30%, P < 0.05) and 7 d (48% ± 38%, P < 0.001) after glucocorticoid administration, compared with placebo, whereas hemoglobin concentration was similar between groups. Additionally, hemoglobin mass was higher ( P < 0.05) 7 d (glucocorticoid, 886 ± 104 g; placebo, 872 ± 103 g) and 21 d (glucocorticoid, 879 ± 111 g; placebo, 866 ± 103 g) after glucocorticoid administration compared with placebo. Mean power output was similar between groups 7 d (glucocorticoid, 278 ± 64 W; placebo, 275 ± 62 W) and 21 d (glucocorticoid, 274 ± 62 W; placebo, 275 ± 60 W) after treatment.

CONCLUSIONS

Intramuscular injection of 40 mg triamcinolone acetonide accelerates erythropoiesis and increases hemoglobin mass but does not improve aerobic exercise performance in the present study. The results are important for sport physicians administering glucocorticoids and prompt a reconsideration of glucocorticoid usage in sport.

Stress, a Brief Update

Stress is fundamental for health and adaptation; it is an evolutionarily conserved response that involves several systems in the organism. The study of the stress response could be traced back to the end of the nineteenth century with George Beard's or Claude Bernard's work and, from that moment on, several studies that have allowed the elucidation of its neurobiology and the consequences of suffering from it were consolidated. In this theoretical review, we discuss the most relevant researches to our knowledge on the study of stress response, from the concept of stress, its neurobiology, the hormonal response during stress, as well as its regulation, the effects of acute and chronic stress, stress from cognition, the different stress responses during life, as well as its relationship with different psychiatric disorders. Taken together, the reviewed research updates the classic perspective on stress, increasing the factors that should be considered in research to explore the effects of stress on health.

Changes in Environmental Stress over COVID-19 Pandemic Likely Contributed to Failure to Replicate Adiposity Phenotype Associated with Krtcap3

We previously identified Keratinocyte-associated protein 3, Krtcap3, as an obesity-related gene in female rats where a whole-body Krtcap3 knock-out (KO) led to increased adiposity compared to wild-type (WT) controls when fed a high-fat diet (HFD). We sought to replicate this work to better understand the function of Krtcap3 but were unable to reproduce the adiposity phenotype. In the current work, WT female rats ate more compared to WT in the prior study, with corresponding increases in body weight and fat mass, while there were no changes in these measures in KO females between the studies. The prior study was conducted before the COVID-19 pandemic, while the current study started after initial lock-down orders and was completed during the pandemic with a generally less stressful environment. We hypothesize that the environmental changes impacted stress levels and may explain the failure to replicate our results. Analysis of corticosterone (CORT) at euthanasia showed a significant study by genotype interaction where WT had significantly higher CORT relative to KO in Study 1, with no differences in Study 2. These data suggest that decreasing Krtcap3 expression may alter the environmental stress response to influence adiposity. We also found that KO rats in both studies, but not WT, experienced a dramatic increase in CORT after their cage mate was removed, suggesting a separate connection to social behavioral stress. Future work is necessary to confirm and elucidate the finer mechanisms of these relationships, but these data indicate the possibility of Krtcap3 as a novel stress gene.