A Rat Model of Post-Traumatic Stress Syndrome Causes Phenotype-Associated Morphological Changes and Hypofunction of the Adrenal Gland

Background: Rats exposed to chronic predator scent stress mimic the phenotype of complex post-traumatic stress disorder (PTSD) in humans, including altered adrenal morphology and function. High- and low-anxiety phenotypes have been described in rats exposed to predator scent stress (PSS). This study aimed to determine whether these high- and low-anxiety phenotypes correlate with changes in adrenal histomorphology and corticosteroid production. Methods: Rats were exposed to PSS for ten days. Thirty days later, the rats’ anxiety index (AI) was assessed with an elevated plus-maze test. Based on differences in AI, the rats were segregated into low- (AI ≤ 0.8, n = 9) and high- (AI > 0.8, n = 10) anxiety phenotypes. Plasma corticosterone (CORT) concentrations were measured by ELISA. Adrenal CORT, desoxyCORT, and 11-dehydroCORT were measured by high-performance liquid chromatography. After staining with hematoxylin and eosin, adrenal histomorphometric changes were evaluated by measuring the thickness of the functional zones of the adrenal cortex. Results: Decreased plasma CORT concentrations, as well as decreased adrenal CORT, desoxyCORT and 11-dehydroCORT concentrations, were observed in high- but not in low-anxiety phenotypes. These decreases were associated with increases in AI. PSS led to a significant decrease in the thickness of the zona fasciculata and an increase in the thickness of the zona intermedia. The increase in the thickness of the zona intermedia was more pronounced in low-anxiety than in high-anxiety rats. A decrease in the adrenal capsule thickness was observed only in low-anxiety rats. The nucleus diameter of cells in the zona fasciculata of high-anxiety rats was significantly smaller than that of control or low-anxiety rats. Conclusion: Phenotype-associated changes in adrenal function and histomorphology were observed in a rat model of complex post-traumatic stress disorder.

β-catenin activation and illicit receptor expression in adrenocortical cells

Adrenal cortisol-producing tumors can express illicit membrane receptors such as luteinizing hormone (LH), glucose-dependent insulinotropic peptide (GIP) or type 4 and 7 serotonin (5-HT4/7) receptors. Abnormal expression of the LH receptor (LH-R) has been ascribed to activation of the Wnt/β-catenin signaling pathway in adrenocortical cells. In the present study, we have investigated whether β-catenin activation may also trigger illegitimate expression of GIP and 5-HT receptors. Three models of β-catenin activation in adrenocortical cells were used: an APC-mutated adrenocortical tumor, human transfected adrenocortical cells and genetically modified mouse adrenal glands. The methods employed included RT-qPCR, immunohistochemistry, and measurement of cortisol secretion by cultured tumor cells. Abnormal expression of the GIP, 5-HT7 and LH receptors was observed in the APC-mutated adrenocortical tumor tissue. In addition, GIP, 5-HT and hCG stimulated cortisol production from tumor cells in primary culture. Conversely, only the LHCGR was upregulated in human and mouse adrenocortical cells harboring activation of β-catenin. Moreover, LH-R immunoreactivity was detected in clusters of zona fasciculata cells in the β-catenin-activated mouse model. Our data indicate that activation of the β-catenin signaling pathway can promote illicit expression of functional LH receptors in adrenal zona fasciculata cells but does not favor abnormal expression of GIP and 5-HT receptors.

Alterations in Cortisol and Interleukin-6 Secretion in Patients With COVID-19 Suggestive of Neuroendocrine-Immune Adaptations

Purpose: The beneficial effect of glucocorticoids in coronavirus disease (COVID-19) is established, but whether adrenal cortisol secretion is impaired in COVID-19 is not fully elucidated. In this case-control study we investigated the diurnal free bioavailable salivary cortisol secretion in COVID-19 patients.Methods: Fifty-two consecutive COVID-19 patients -before dexamethasone treatment- recruited between April 15th -June15th-2021, (NCT04988269) at Laikon Athens University-Hospital, and 33 healthy age- and sex-matched controls were included. Diurnal salivary cortisol (8am, 12, 6, and 10pm), plasma adrenocorticotropin (ACTH) and aldosterone, and serum interleukin-6 (IL-6) and C-reactive protein (CRP) levels were assessed. Diurnal salivary dehydroepiandrosterone (DHEA) and IL-6 were also assessed in subgroups of patients.ResultsMedian CRP and IL-6 measurements were about 6-fold higher in patients than controls (both p<0.001) Morning salivary cortisol levels did not differ between the two groups, but patients exhibited higher median levels of evening and nocturnal salivary cortisol compared to controls [0.391(0.054, 0,663) vs. 0.081(0.054, 0.243)μg/dl, p<0.001 and 0.183(0.090, 0.834) vs. 0.054(0.054, 0.332)μg/dl, p<0.001, respectively], resulting in higher time-integrated area under the curve (AUC) (4.81±2.46 vs. 2.75±0.810, respectively, p<0.001). Circulating ACTH, DHEA, and aldosterone levels were similar in patients and controls. Serum IL-6, but not ACTH levels, WAS strongly correlated with nocturnal cortisol salivary levels (rho=0.555, p<0.001) in patients.ConclusionIncreased evening and nocturnal but not morning cortisol secretion occur in even clinically mild COVID-19. In the context of acute viral infection (Covid-19), IL-6 may partially replace ACTH as a stimulus of the glucocorticoid-secreting adrenal zona-fasciculata without influencing the secretion of DHEA and aldosterone.

Dichlorodiphenyltrichloroethane and the Adrenal Gland: From Toxicity to Endocrine Disruption

Endocrine disruptors are exogenous compounds that pollute the environment and have effects similar to hormones when inside the body. One of the most widespread endocrine disruptors in the wild is the pesticide dichlorodiphenyltrichloroethane (DDT). Toxic doses of DDT are known to cause cell atrophy and degeneration in the adrenal zona fasciculata and zona reticularis. Daily exposure in a developing organism to supposedly non-toxic doses of DDT have been found to impair the morphogenesis of both the cortex and the medulla of the adrenal glands, as well as disturbing the secretion of hormones in cortical and chromaffin cells. Comparison of high and very low levels of DDT exposure revealed drastic differences in the morphological and functional changes in the adrenal cortex. Moreover, the three adrenocortical zones have different levels of sensitivity to the disruptive actions of DDT. The zona glomerulosa and zona reticularis demonstrate sensitivity to both high and very low levels of DDT in prenatal and postnatal periods. In contrast, the zona fasciculata is less damaged by low (supposedly non-toxic) exposure to DDT and its metabolites but is affected by toxic levels of exposure; thus, DDT exerts both toxic and disruptive effects on the adrenal glands, and sensitivity to these two types of action varies in adrenocortical zones. Disruptive low-dose exposure leads to more severe affection of the adrenal function.

Morphologic and Molecular Characterization of Adrenals and Adrenal Rest Affected by Congenital Adrenal Hyperplasia

IntroductionAdrenocortical hyperplasia and adrenal rest tumor (ART) formation are common in congenital adrenal hyperplasia (CAH). Although driven by excessive corticotropin, much is unknown regarding the morphology and transformation of these tissues. Our study objective was to characterize CAH-affected adrenals and ART and compare with control adrenal and gonadal tissues.Patients/MethodsCAH adrenals, ART and control tissues were analyzed by histology, immunohistochemistry, and transcriptome sequencing. We investigated protein expression of the ACTH receptor (MC2R), steroidogenic (CYP11B2, CYP11B1, CYB5A) and immune (CD20, CD3, CD68) biomarkers, and delta-like 1 homolog (DLK1), a membrane bound protein broadly expressed in fetal and many endocrine cells. RNA was isolated and gene expression was analyzed by RNA sequencing (RNA-seq) followed by principle component, and unsupervised clustering analyses.ResultsBased on immunohistochemistry, CAH adrenals and ART demonstrated increased zona reticularis (ZR)-like CYB5A expression, compared to CYP11B1, and CYP11B2, markers of zona fasciculata and zona glomerulosa respectively. CYP11B2 was mostly absent in CAH adrenals and absent in ART. DLK1 was present in CAH adrenal, ART, and also control adrenal and testis, but was absent in control ovary. Increased expression of adrenocortical marker MC2R, was observed in CAH adrenals compared to control adrenal. Unlike control tissues, significant nodular lymphocytic infiltration was observed in CAH adrenals and ART, with CD20 (B-cell), CD3 (T-cell) and CD68 (macrophage/monocyte) markers of inflammation. RNA-seq data revealed co-expression of adrenal MC2R, and testis-specific INSL3, HSD17B3 in testicular ART indicating the presence of both gonadal and adrenal features, and high expression of DLK1 in ART, CAH adrenals and control adrenal. Principal component analysis indicated that the ART transcriptome was more similar to CAH adrenals and least similar to control testis tissue.ConclusionsCAH-affected adrenal glands and ART have similar expression profiles and morphology, demonstrating increased CYB5A with ZR characteristics and lymphocytic infiltration, suggesting a common origin that is similarly affected by the abnormal hormonal milieu. Immune system modulators may play a role in tumor formation of CAH.

Adrenal glands of mice and rats: A comparative morphometric study

Mice and rats are among the most used laboratory animals. They share numerous similarities along with differences, some yet unexplored. One of them is the morphometry of their adrenal glands, whose characteristics may be related to differences in energy management, immune response, drug metabolism, behaviour and temperament. The present study tries to fill this knowledge gap with the evaluation and comparison of adrenal gland anatomical/morphometric parameters of mice and rats. In groups of 10 ( n = 10) adult, male and female BALB/c mice and Wistar rats, one in every 20 sections transverse to the longitudinal axis of the gland was used for measuring entire gland area, capsule, entire cortex, cortex zones and medulla with the aid of an image analysis system and subjected to statistical analysis. Quotients of the individual areas were calculated and comparison between the resulting ratios was performed. Gland length and volume were also calculated. Statistically significant differences were revealed between the rat female and male cortex area, rat and mouse medulla/cortex, medulla/gland, zona glomerulosa/cortex and cortex/gland ratios, male and female rats’ medulla/cortex, medulla/gland, capsule/gland, zona glomerulosa/cortex, zona reticularis/cortex and zona glomerulosa/zona fasciculata ratios, length and volume. The correlation evaluation revealed that in male rats and in female mice the larger medulla area was accompanied by a larger cortex area and vice versa. In general, a larger cortex area was accompanied by larger areas of cortex zones. The collected data and the revealed differences can possibly contribute to the understanding of the physiology of the two species.

Cortisol in Oral and Maxillofacial Surgery: A Double-Edged Sword

Cortisol is a hormone that is naturally produced by the zona fasciculata of the cortex in the adrenal gland. One of its main functions is to decrease inflammation, particularly in areas where an inflammatory response is not necessary. In the field of oral and maxillofacial surgery, cortisol is used to improve the outcomes of surgical procedures and to make the postoperative period more comfortable for the patient. However, cortisol is considered a double-edged sword because its use is associated with both benefits and adverse effects. It is imperative to use cortisol following an accurate diagnosis, in addition to clarity regarding the desired surgical procedure for treating the acute or chronic condition affecting the patient. When used with caution, cortisol can serve as a valuable agent for reducing the postoperative inflammatory response in patients undergoing moderate as well as moderately severe surgical procedures.

Latent Adrenal Insufficiency: From Concept to Diagnosis

Primary adrenal insufficiency (PAI) is a rare disease and potentially fatal if unrecognized. It is characterized by destruction of the adrenal cortex, most frequently of autoimmune origin, resulting in glucocorticoid, mineralocorticoid, and adrenal androgen deficiencies. Initial signs and symptoms can be nonspecific, contributing to late diagnosis. Loss of zona glomerulosa function may precede zona fasciculata and reticularis deficiencies. Patients present with hallmark manifestations including fatigue, weight loss, abdominal pain, melanoderma, hypotension, salt craving, hyponatremia, hyperkalemia, or acute adrenal crisis. Diagnosis is established by unequivocally low morning serum cortisol/aldosterone and elevated ACTH and renin concentrations. A standard dose (250 µg) Cosyntropin stimulation test may be needed to confirm adrenal insufficiency (AI) in partial deficiencies. Glucocorticoid and mineralocorticoid substitution is the hallmark of treatment, alongside patient education regarding dose adjustments in periods of stress and prevention of acute adrenal crisis. Recent studies identified partial residual adrenocortical function in patients with AI and rare cases have recuperated normal hormonal function. Modulating therapies using rituximab or ACTH injections are in early stages of investigation hoping it could maintain glucocorticoid residual function and delay complete destruction of adrenal cortex.