scholarly journals Autoantibodies reactive to adrenocorticotropic hormone can alter cortisol secretion in both aggressive and nonaggressive humans

2018 ◽  
Vol 115 (28) ◽  
pp. E6576-E6584 ◽  
Author(s):  
Henning Værøy ◽  
Csaba Adori ◽  
Romain Legrand ◽  
Nicolas Lucas ◽  
Jonathan Breton ◽  
...  
Keyword(s):  
Amino Acids ◽  
Adrenocorticotropic Hormone ◽  
Cortisol Secretion ◽  
Adrenal Cells ◽  
Igg Binding ◽  
History Of ◽  
Response To Stress ◽  
Underlying Mechanisms ◽  
Epitope Binding

Violent aggression in humans may involve a modified response to stress, but the underlying mechanisms are not well understood. Here we show that naturally present autoantibodies reactive to adrenocorticotropic hormone (ACTH) exhibit distinct epitope-binding profiles to ACTH peptide in subjects with a history of violent aggression compared with controls. Namely, while nonaggressive male controls displayed a preferential IgG binding to the ACTH central part (amino acids 11–24), subjects who had committed violent acts of aggression had IgG with increased affinity to ACTH, preferentially binding to its N terminus (amino acids 1–13). Purified IgGs from approximately half of the examined sera were able to block ACTH-induced cortisol secretion of human adrenal cells in vitro, irrespective of the source of sample (from a control subject or a violent aggressor). Nevertheless, in the resident–intruder test in mice, i.p. injection of residents with ACTH and IgG from aggressive subjects, but not from control subjects, shortened latency for the first attack against intruders. Immunohistochemical screening of violent aggressors’ sera on rat brain and pituitary sections did not show IgG binding to ACTH-producing cells, but 4 of 16 sera revealed selective binding to a nonidentified antigen in vasopressinergic neurons of the hypothalamic paraventricular and supraoptic nuclei. Thus, the data show that ACTH-reactive plasmatic IgGs exhibit differential epitope preference in control and violently aggressive subjects. These IgGs can modulate ACTH-induced cortisol secretion and, hence, are involved in the regulation of the stress response. However, the possible role of ACTH-reactive autoantibodies in aggressive behavior needs further investigation.

scholarly journals The RNA origin of transfer RNA aminoacylation and beyond

2011 ◽  
Vol 366 (1580) ◽  
pp. 2959-2964 ◽  
Author(s):  
Hiroaki Suga ◽  
Gosuke Hayashi ◽  
Naohiro Terasaka
Keyword(s):  
Amino Acids ◽  
Evolutionary History ◽  
Transfer Rna ◽  
Translation System ◽  
Rna Sequences ◽  
Rna Molecules ◽  
Rna Catalysts ◽  
Modern System ◽  
History Of

Aminoacylation of tRNA is an essential event in the translation system. Although in the modern system protein enzymes play the sole role in tRNA aminoacylation, in the primitive translation system RNA molecules could have catalysed aminoacylation onto tRNA or tRNA-like molecules. Even though such RNA enzymes so far are not identified from known organisms, in vitro selection has generated such RNA catalysts from a pool of random RNA sequences. Among them, a set of RNA sequences, referred to as flexizymes (Fxs), discovered in our laboratory are able to charge amino acids onto tRNAs. Significantly, Fxs allow us to charge a wide variety of amino acids, including those that are non-proteinogenic, onto tRNAs bearing any desired anticodons, and thus enable us to reprogramme the genetic code at our will. This article summarizes the evolutionary history of Fxs and also the most recent advances in manipulating a translation system by integration with Fxs.

scholarly journals Food-Dependent Cushing’s Syndrome: Possible Involvement of Leptin in Cortisol Hypersecretion*

1999 ◽  
Vol 84 (10) ◽  
pp. 3817-3822 ◽  
Author(s):  
François P. Pralong ◽  
Fulgencio Gomez ◽  
Louis Guillou ◽  
François Mosimann ◽  
Sebastiano Franscella ◽  
...  
Keyword(s):  
Food Intake ◽  
Cushing’S Syndrome ◽  
Adrenal Adenoma ◽  
Cushing's Syndrome ◽  
Cortisol Secretion ◽  
Adrenal Hyperplasia ◽  
Adrenal Cells ◽  
Patient Reported ◽  
Stimulation Of

Abstract Stimulation of cortisol secretion by food intake has been implicated in the pathogenesis of some cases of ACTH-independent Cushing’s syndrome, via an aberrant response of the adrenal glands to gastric inhibitory polypeptide (GIP). We report here a novel case of food-dependent Cushing’s syndrome in a patient with bilateral macronodular adrenal hyperplasia. In this patient we were able to confirm a paradoxical stimulation of cortisol secretion by GIP in vivo as well as in vitro on dispersed tumor adrenal cells obtained at surgery. In addition to GIP, in vitro stimulation of these cultured tumor adrenal cells with leptin, the secreted product of the adipocyte, induced cortisol secretion. By comparison, no such stimulation was observed in vitro in adrenal cells obtained from another patient with bilateral macronodular adrenal hyperplasia and Cushing’s syndrome that did not depend on food intake, in tumor cells obtained from a solitary cortisol-secreting adrenal adenoma, and in normal human adrenocortical cells. These results demonstrate that as in previously described cases of food-dependent Cushing’s syndrome, GIP stimulated cortisol secretion from the adrenals of the patient reported here. Therefore, they indicate that such a paradoxical response probably represents the hallmark of this rare condition. In addition, they suggest that leptin, which normally inhibits stimulated cortisol secretion in humans, participated in cortisol hypersecretion in this case. Further studies in other cases of food-dependent Cushing’s syndrome, however, will be necessary to better ascertain the pathophysiological significance of this finding.

scholarly journals Mimecan Regulates Corticosterone Secretion and Plays A Critical Role in Adrenal Responses to Stress

2020 ◽  
Author(s):  
Bin Su ◽  
Qianyue Zhang ◽  
Xuesong Li ◽  
Huimin Yu ◽  
Ping Li ◽  
...  
Keyword(s):  
Hpa Axis ◽  
Restraint Stress ◽  
Adrenocorticotropic Hormone ◽  
Critical Role ◽  
Host Defenses ◽  
Litter Mate ◽  
Adrenal Cells ◽  
Corticosterone Secretion

Abstract Background: A functional hypothalamic-pituitary-adrenal (HPA) axis is critical for host defenses to outside stimuli. The adrenal cortex is seemingly endowed with distinct functional units that are regulated by adrenocorticotropic hormone (ACTH). We have found that mimecan, a small leucine-rich proteoglycan expressed in the adrenal gland, has yet to be characterized in functional terms.Results: Herein, we have demonstrated the following properties: 1) adrenal mimecan expression in mouse models is significantly downregulated under hypoglycemia and scalded stress; 2) expression of mimecan in adrenal cells may be downregulated through ACTH or upregulated by glucocorticoid via related receptors (GRs); and 3) mimecan stimulates corticosterone secretion in adrenal tissues. The latter was proven using in vivo and in vitro studies to confirm the ACTH-independent activity of mimecan-maltose-binding protein (-MBP). Relative to litter-mate mice, the basal-state diurnal rhythm of corticosterone secretion is disrupted in mimecan knockout mice, and corticosterone secretion is increased under restraint stress conditions. Conclusions: These findings offer the first evidence that mimecan is key in regulating the HPA axis, assuming a critical role in adrenal responses to stress.

Primary adrenocortical micronodular adenomatosis causing Cushing's syndrome. Effects of ketoconazole on steroid production and in vitro performance of adrenal cells

1986 ◽  
Vol 113 (3) ◽  
pp. 370-377 ◽  
Author(s):  
W. Oelkers ◽  
V. Bähr ◽  
J. Hensen ◽  
H. Pickartz ◽  
P. Exner ◽  
...  
Keyword(s):  
Cushing’S Syndrome ◽  
Plasma Cortisol ◽  
Venous Blood ◽  
Clinical Signs ◽  
Cushing's Syndrome ◽  
Cortisol Secretion ◽  
Urinary Cortisol ◽  
Adrenal Cells

Abstract. Mild Cushing's syndrome was diagnosed in a 35 year old woman. Elevated plasma and urinary cortisol levels were unsuppressible with up to 32 mg dexamethasone per day. Aldosterone, 18-OH-corticosterone and testosterone in plasma were normal and dehydroepiandrosterone-sulphate was low. No adrenal tumour was found by CT or adrenal venography, and bilateral cortisol secretion was demonstrated by steroid measurements in adrenal venous blood. A circadian rhythm of plasma cortisol was absent. Plasma ACTH was suppressed, even after injection of CRH, during insulininduced hypoglycaemia and after metyrapone administration, which led to a large fall in plasma cortisol but to a subnormal rise of plasma 11-deoxy-cortisol. The clinical diagnosis of primary micronodular adenomatosis of the adrenal gland was histologically confirmed, when the patient finally underwent bilateral adrenalectomy. In vitro, the adrenal cells did not produce more cortisol and aldosterone than adrenal cells from cadaver kidney donors. In vivo and in vitro, cortisol was slightly less than normally responsive to ACTH. Intermittent treatment of the patient with 800 mg/day of ketoconazole led to a rapid fall of cortisol secretion and clinical signs of adrenocortical insufficiency. Treatment for 7 weeks with 200–400 mg ketoconazole per day reduced plasma and urinary cortisol less dramatically into the normal range. This case unequivocally documents autonomous dysfunction of the adrenal cortex in this rare form of Cushing's syndrome and the efficacy of ketoconazole in the treatment of ACTH-independent hypercortisolism.

scholarly journals On the Assessment of the in Vitro Biopotency and Site(s) of Action of Drugs Affecting Adrenal Steroidogenesis

1986 ◽  
Vol 23 (3) ◽  
pp. 225-229 ◽  
Author(s):  
A Lambert ◽  
J Frost ◽  
R Mitchell ◽  
W R Robertson
Keyword(s):  
Guinea Pig ◽  
Cyproterone Acetate ◽  
Hydroxysteroid Dehydrogenase ◽  
Megestrol Acetate ◽  
Cortisol Secretion ◽  
Adrenal Cells ◽  
Adrenal Steroidogenesis ◽  
Biological Potency ◽  
Sites Of Action

Dispersed guinea-pig adrenal cells have been employed in the in vitro estimation of the biological potency and sites of action of drugs acting against the adrenal. The effect of 12 drugs on cortisol secretion from cells stimulated with adrenocorticotrophin (ACTH, 50 ng/L, a 95% saturating dose) has been tested. All the drugs depressed cortisol output in a dose-related fashion. The concentration of drug which inhibited secretion by 50% was (μmol/L, mean±SEM): etomidate 0·1±0·002; epostane 0·44±0·02: 17-ketotrilostane 0·55±0·04: trilostane 1·3±0·1: metyrapone 3·5±0·6: cyproterone acetate 4·6±0·2: megestrol acetate 11±2: danazol 22±2: aminoglutethimide 41±5: stanozolol 50±4: thiopentone 160±18: propofol 170±18. The sites of the anti-steroidogenic effect of seven of these drugs have also been established using a method based upon the sequential stimulation by the exogenous precursor steroids of the various steps leading to the biosynthesis of cortisol by adrenal cells. Propofol acts between ACTH binding and pregnenolone production, trilostane, megestrol acetate and cyproterone acetate are 3β-hydroxysteroid dehydrogenase inhibitors whereas metyrapone, etomidate and thiopentone act at 11β-hydroxylase.

scholarly journals Supplementation with Branched-Chain Amino Acids Induces Unexpected Deleterious Effects on Astrocyte Survival and Intracellular Metabolism with or without Hyperammonemia: A Preliminary In Vitro Study

2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Ting Wang ◽  
Kazuyuki Suzuki ◽  
Toshimi Chiba ◽  
Keisuke Kakisaka ◽  
Yasuhiro Takikawa
Keyword(s):  
Amino Acids ◽  
In Vitro Study ◽  
Branched Chain Amino Acids ◽  
Metabolome Analysis ◽  
Negative Effects ◽  
Human Astrocytes ◽  
Intracellular Metabolism ◽  
Branched Chain ◽  
Underlying Mechanisms

Introduction. Ammonia is a key component in the pathogenesis of hepatic encephalopathy. Branched-chain amino acids (BCAA) have been reported to improve the symptoms of HE induced by hyperammonemia; however, we recently reported that ammonia increases intracellular levels of BCAA and exerts toxic effects on astrocytes. Objectives. This follow-up study was designed to confirm the direct effects of BCAA on human astrocytes and clarify their underlying mechanisms using metabolome analysis and evaluation of associated signaling. Methods. We performed cytotoxicity and cell proliferation tests on astrocytes following BCAA treatment with and without ammonium chloride (NH4Cl) and then compared the results with the effects of BCAA on hepatocytes and neurons. Subsequently, we used metabolomic analysis to investigate intracellular metabolite levels in astrocytes with and without BCAA treatment. Results. The astrocytes showed increased leakage of intracellular lactate dehydrogenase and reduced proliferation rate upon BCAA treatment. Interestingly, our analysis showed a BCAA-induced impairment of intracellular glycolysis/glyconeogenesis as well as amino acid and butyric acid metabolism. Furthermore, BCAA treatment was found to cause decreased levels of Glut-1 and phosphorylated GSK-3β and mTOR in astrocytes. Conclusions. Although further investigations of the effect of BCAA on human astrocytes with hyperammonemia are needed, our work demonstrates that BCAA supplementation has direct negative effects on astrocyte survival and intracellular metabolism.

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