A single nucleotide polymorphism in the corticotropin receptor gene is associated with a blunted cortisol response during pediatric critical illness

The horizon of pediatric cardiac critical care

Pediatric Cardiac Critical Care (PCCC) is a challenging discipline where decisions require a high degree of preparation and clinical expertise. In the modern era, outcomes of neonates and children with congenital heart defects have dramatically improved, largely by transformative technologies and an expanding collection of pharmacotherapies. Exponential advances in science and technology are occurring at a breathtaking rate, and applying these advances to the PCCC patient is essential to further advancing the science and practice of the field. In this article, we identified and elaborate on seven key elements within the PCCC that will pave the way for the future.

The influence of TNF-α on the expression profile of key enzymes of steroidogenesis in H295R cells

INTRODUCTION

Tumor necrosis factor-α (TNF-α) plays an extremely important role in the regulation of hypothalamicpituitary-adrenal axis. It is believed that chronic inflammation is the main cause of cancerogenesis and TNF-α plays a significant role in both of these processes. Unfortunately, the function of TNF-α in human adrenal steroidogenesis has not been explained enough.

AIM

To evaluate the changes in transcriptional activity of STAR, CYP11A1, CYP11B1, and CYP11B2 in H295R cell line exposed to TNF-α.

MATERIAL AND METHODS

NCI-H295R, human adrenocortical cell line was exposed to human recombinant TNF-α at the concentrations ranging from 0.001 to 10 nM for 3, 12, 24, and 48 h. Cells not exposed to TNF-α were the control of this experiment. RTqPCR assay was used to determine the changes in the expression of genes encoding STAR, CYP11A1, CYP11B1, and CYP11B2.

RESULTS

The highest differences between stimulated and non-stimulated cells were observed in the expression of STAR (FC = +2.2; 0.01 nM of TNF-α; 48 h); CYP11A1 (FC = +3.5; 0.1 nM of TNF-α; 24 h); CYP11B1 (FC = +7.0; 10 nM of TNF-α; 48 h); CYP11B2 (FC = +2.5; 10 nM of TNF-α; 48 h). Statistically significant differences (p < 0.05) in the expression were found only for CYP11A1. The interaction effect between genes was also noticed (p < 0.05).

CONCLUSIONS

The research showed the impact of TNF-α on the expression of the key genes encoding enzymes involved in adrenal steroidogenesis. Different expression patterns of was observed, depending on time and TNF-α concentration increased synthesis of this pro-inflammatory cytokine may intensify adrenal steroidogenesis.

Trait mindfulness predicts the presence but not the magnitude of cortisol responses to acute stress

BACKGROUND

Mindfulness, or the practice of observing present moment experiences with acceptance, is thought to improve health at least partially by limiting hypothalamic-pituitary-adrenal (HPA) axis over-responsiveness during episodes of acute stress. However, models of allostatic load suggest that HPA axis under-responsiveness can also be detrimental to health, and the relationship between mindfulness and cortisol under-responsiveness has yet to be examined. The present study therefore aimed to address this knowledge gap, and to revisit the relationship between mindfulness and acute cortisol response magnitude while excluding (or statistically controlling for) individuals displaying HPA axis under-responsiveness.

METHODS

Participants (124 healthy undergraduate students) were subjected to a stressful speech task, and completed a trait mindfulness questionnaire. Salivary cortisol was collected 0, +15, +25, +40, and +55 min post-stressor onset.

RESULTS

Greater trait mindfulness was associated with greater odds of displaying a cortisol response relative to none, but was unrelated to the magnitude of cortisol responses among those who displayed an acute response.

CONCLUSIONS

In the present sample, trait mindfulness was associated with cortisol responses, but this was driven by the fact that subjects low in mindfulness were more likely to be non-responders. Contrasting the effects of mindfulness on the presence (i.e., present vs. absent) and the degree (i.e., magnitude) of acute stress responses may therefore be warranted in future research.

Glucocorticoid Receptor Polymorphisms and Outcomes in Pediatric Septic Shock

OBJECTIVE

Polymorphisms of the glucocorticoid receptor gene are associated with outcome and corticosteroid responsiveness among patients with inflammatory disorders. We conducted a candidate gene association study to test the hypothesis that these polymorphisms are associated with outcome and corticosteroid responsiveness among children with septic shock.

DESIGN

We genotyped 482 children with septic shock for the presence of two glucocorticoid receptor polymorphisms (rs56149945 and rs41423247) associated with increased sensitivity and one glucocorticoid receptor polymorphism (rs6198) associated with decreased sensitivity to corticosteroids. The primary outcome variable was complicated course, defined as 28-day mortality or the persistence of two or more organ failures 7 days after a septic shock diagnosis. We used logistic regression to test for an association between corticosteroid exposure and outcome, within genotype group, and adjusted for illness severity.

SETTING

Multiple PICUs in the United States.

INTERVENTIONS

Standard care.

MEASUREMENTS AND MAIN RESULTS

There were no differences in outcome when comparing the various genotype groups. Among patients homozygous for the wild-type glucocorticoid receptor allele, corticosteroids were independently associated with increased odds of complicated course (odds ratio, 2.30; 95% CI, 1.01-5.21; p = 0.047).

CONCLUSIONS

Based on these glucocorticoid receptor polymorphisms, we could not detect a beneficial effect of corticosteroids among any genotype group. Among children homozygous for the wild-type allele, corticosteroids were independently associated with increased odds of poor outcome.

Emerging therapies for the treatment of sepsis

PURPOSE OF REVIEW

Sepsis affects patients of all ages with multiple comorbidities and underlying diagnoses, and is the result of infection by many potential pathogens infecting various organs or sites. Many molecules have been clinically tested in recent years for their potential immunomodulatory effects, but have been shown to have no beneficial effects on outcomes in heterogeneous populations of patients with sepsis. There are, therefore, no specific antisepsis therapies and mortality and morbidity rates remain high despite improved overall management of these patients. This review covers promising agents currently used in clinical trials.

RECENT FINDINGS

There are several candidates currently undergoing early and later phase of clinical testing, including thrombomodulin, alkaline phosphatase, interferon-beta, and selepressin. Other approaches including immunoglobulins, extracorporeal therapies, and pharmaconutrients will also be discussed.

SUMMARY

Despite multiple trials of potential therapies for sepsis, no strategies have yet been persistently shown to have beneficial effects on outcomes. The main reason for the disappointing results is that patient populations in these studies have been too heterogeneous. Selecting patients on the basis of general symptoms is not enough. Rather patients should be selected according to the likely action of the drug in question. To achieve this, improved biomarkers of sepsis and of the immune response are needed and the activities of the individual agents need to be carefully characterized. New candidates are being developed and the results of ongoing and recent clinical trials of immunomodulatory therapies are eagerly awaited as new therapies for sepsis are urgently needed.