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"Schneider, Holger"
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International Histopathology Consensus for Unilateral Primary Aldosteronism
by
Zerbini, Maria Claudia Nogueira
,
Papotti, Mauro
,
Saeger, Wolfgang
in
Adrenal Glands - metabolism
,
Adrenal Glands - pathology
,
Adrenalectomy - methods
2021
Abstract
Objective
Develop a consensus for the nomenclature and definition of adrenal histopathologic features in unilateral primary aldosteronism (PA).
Context
Unilateral PA is the most common surgically treated form of hypertension. Morphologic examination combined with CYP11B2 (aldosterone synthase) immunostaining reveals diverse histopathologic features of lesions in the resected adrenals.
Patients and Methods
Surgically removed adrenals (n = 37) from 90 patients operated from 2015 to 2018 in Munich, Germany, were selected to represent the broad histologic spectrum of unilateral PA. Five pathologists (Group 1 from Germany, Italy, and Japan) evaluated the histopathology of hematoxylin-eosin (HE) and CYP11B2 immunostained sections, and a consensus was established to define the identifiable features. The consensus was subsequently used by 6 additional pathologists (Group 2 from Australia, Brazil, Canada, Japan, United Kingdom, United States) for the assessment of all adrenals with disagreement for histopathologic diagnoses among group 1 pathologists.
Results
Consensus was achieved to define histopathologic features associated with PA. Use of CYP11B2 immunostaining resulted in a change of the original HE morphology-driven diagnosis in 5 (14%) of 37 cases. Using the consensus criteria, group 2 pathologists agreed for the evaluation of 11 of the 12 cases of disagreement among group 1 pathologists.
Conclusion
The HISTALDO (histopathology of primary aldosteronism) consensus is useful to standardize nomenclature and achieve consistency among pathologists for the histopathologic diagnosis of unilateral PA. CYP11B2 immunohistochemistry should be incorporated into the routine clinical diagnostic workup to localize the likely source of aldosterone production.
Journal Article
Adrenal insufficiency after unilateral adrenalectomy in primary aldosteronism – long-term outcome and clinical impact
2019
Primary aldosteronism (PA) represents a secondary form of arterial hypertension that can be cured by surgery. Evidence of adrenal insufficiency (AI) was recently found in patients with PA who had undergone unilateral adrenalectomy (uADX).
To study the incidence and long-term outcome of postoperative AI after uADX for PA.
Prospective registry study (August 2014 until the end of 2018).
Tertiary referral center.
One hundred consecutive patients undergoing uADX for PA were included. All patients underwent postoperative ACTH stimulation testing.
Postoperative ACTH stimulation testing to identify patients with AI.
Incidence of patients with postoperative AI and definition of long-term outcome.
Twenty-seven percent of patients developed postoperative AI. Of these, 48% had postoperative ACTH stimulation serum cortisol levels ≤13.5 µg/dL (severe AI); 52% were classified into the group with moderate AI (stimulated serum cortisol levels: 13.5 to 17 µg/dL). Patients with severe AI required significantly longer hydrocortisone replacement therapy than the moderate group (median [25th, 75th percentiles]: 353 [294, 476] days; 95% CI: 284 to 322 days; vs 74 [32, 293] days; 95% CI: 11 to 137 days; P = 0.016). One patient with severe AI was hospitalized for an acute adrenal crisis. With a cumulative follow-up of 14.5 years, this produced an incidence rate of 6.9 adrenal crises per 100 patient-years.
We suggest performing postoperative ACTH stimulation tests in all patients who undergo uADX for PA.
Journal Article
The mitochondrial thioredoxin reductase system (TrxR2) in vascular endothelium controls peroxynitrite levels and tissue integrity
by
Singer, Miriam
,
Lange-Sperandio, Bärbel
,
Kirsch, Julian
in
Biological Sciences
,
Medical Sciences
2021
The mitochondrial thioredoxin/peroxiredoxin system encompasses NADPH, thioredoxin reductase 2 (TrxR2), thioredoxin 2, and peroxiredoxins 3 and 5 (Prx3 and Prx5) and is crucial to regulate cell redox homeostasis via the efficient catabolism of peroxides (TrxR2 and Trxrd2 refer to the mitochondrial thioredoxin reductase protein and gene, respectively). Here, we report that endothelial TrxR2 controls both the steady-state concentration of peroxynitrite, the product of the reaction of superoxide radical and nitric oxide, and the integrity of the vascular system. Mice with endothelial deletion of the Trxrd2 gene develop increased vascular stiffness and hypertrophy of the vascular wall. Furthermore, they suffer from renal abnormalities, including thickening of the Bowman’s capsule, glomerulosclerosis, and functional alterations. Mechanistically, we show that loss of Trxrd2 results in enhanced peroxynitrite steady-state levels in both vascular endothelial cells and vessels by using a highly sensitive redox probe, fluoresceinboronate. High steady-state peroxynitrite levels were further found to coincide with elevated protein tyrosine nitration in renal tissue and a substantial change of the redox state of Prx3 toward the oxidized protein, even though glutaredoxin 2 (Grx2) expression increased in parallel. Additional studies using a mitochondriaspecific fluorescence probe (MitoPY1) in vessels revealed that enhanced peroxynitrite levels are indeed generated in mitochondria. Treatment with Mn(III)tetrakis(1-methyl-4-pyridyl)porphyrin [Mn(III) TMPyP], a peroxynitrite-decomposition catalyst, blunted intravascular formation of peroxynitrite. Our data provide compelling evidence for a yet-unrecognized role of TrxR2 in balancing the nitric oxide/peroxynitrite ratio in endothelial cells in vivo and thus establish a link between enhanced mitochondrial peroxynitrite and disruption of vascular integrity.
Journal Article
Sex-dependent modulation of T and NK cells and gut microbiome by low sodium diet in patients with primary aldosteronism
by
Lechner, Andreas
,
Bidlingmaier, Martin
,
Reisch, Nicole
in
Adult
,
Antibodies
,
Antihypertensives
2024
High dietary sodium intake is a major cardiovascular risk factor and adversely affects blood pressure control. Patients with primary aldosteronism (PA) are at increased cardiovascular risk, even after medical treatment, and high dietary sodium intake is common in these patients. Here, we analyze the impact of a moderate dietary sodium restriction on microbiome composition and immunophenotype in patients with PA.
Prospective two-stage clinical trial including two subgroups: 15 treatment-naive PA patients compared to matched normotensive controls; and 31 PA patients on mineralocorticoid receptor antagonist treatment before and three months after sodium restriction. Patients underwent blood pressure measurements, laboratory tests, analysis of peripheral blood mononuclear cells via flow cytometry and microbiome analysis.
We observed a higher percentage of Tregs in treatment-naive PA patients (p = 0.0303), while the abundance of
was higher in PA patients compared to normotensive controls (p = 0.00027) and the abundance of
species however was higher in the subgroup of normotensive controls (p = 0.0290). Sodium restriction was accompanied by a decrease in pro-inflammatory Tc17 cells in male patients (p = 0.0081, females p = 0.3274).
abundance was higher in female patients (0.01230, p = 0.0016) and decreased upon sodium restriction (0.002309, p = 0.0068).
Dietary sodium restriction in patients with PA modulates the peripheral immune cell composition toward a less inflammatory phenotype. This suggests a potential mechanism by which sodium reduction modulates immune cell composition, leading to blood pressure reduction and positively impacting cardiovascular risk.
Journal Article
Major immunophenotypic abnormalities in patients with primary adrenal insufficiency of different etiology
by
Reisch, Nicole
,
Auer, Matthias K.
,
Marchant Seiter, Thomas
in
12-O-Tetradecanoylphorbol-13-acetate
,
Acetic acid
,
ACTH
2023
Patients with primary adrenal insufficiency (PAI) suffer from increased risk of infection, adrenal crises and have a higher mortality rate. Such dismal outcomes have been inferred to immune cell dysregulation because of unphysiological cortisol replacement. As the immune landscape of patients with different types of PAI has not been systematically explored, we set out to immunophenotype PAI patients with different causes of glucocorticoid (GC) deficiency.
This cross-sectional single center study includes 28 patients with congenital adrenal hyperplasia (CAH), 27 after bilateral adrenalectomy due to Cushing's syndrome (BADx), 21 with Addison's disease (AD) and 52 healthy controls. All patients with PAI were on a stable GC replacement regimen with a median dose of 25 mg hydrocortisone per day. Peripheral blood mononuclear cells were isolated from heparinized blood samples. Immune cell subsets were analyzed using multicolor flow cytometry after four-hour stimulation with phorbol myristate acetate and ionomycin. Natural killer (NK-) cell cytotoxicity and clock gene expression were investigated.
The percentage of T helper cell subsets was downregulated in AD patients (Th1 p = 0.0024, Th2 p = 0.0157, Th17 p < 0.0001) compared to controls. Cytotoxic T cell subsets were reduced in AD (Tc1 p = 0.0075, Tc2 p = 0.0154) and CAH patients (Tc1 p = 0.0055, Tc2 p = 0.0012) compared to controls. NKCC was reduced in all subsets of PAI patients, with smallest changes in CAH. Degranulation marker CD107a expression was upregulated in BADx and AD, not in CAH patients compared to controls (BADx p < 0.0001; AD p = 0.0002). In contrast to NK cell activating receptors, NK cell inhibiting receptor CD94 was upregulated in BADx and AD, but not in CAH patients (p < 0.0001). Although modulation in clock gene expression could be confirmed in our patient subgroups, major interindividual-intergroup dissimilarities were not detected.
In patients with different etiologies of PAI, distinct differences in T and NK cell-phenotypes became apparent despite the use of same GC preparation and dose. Our results highlight unsuspected differences in immune cell composition and function in PAI patients of different causes and suggest disease-specific alterations that might necessitate disease-specific treatment.
Journal Article
Segmental Pulse Volume Recordings at the Forefoot Level as a Valuable Diagnostic Tool for Detection of Peripheral Arterial Disease in the Diabetic Foot Syndrome
2025
Introduction: Evidence for the diagnostic yield of noninvasive diagnostic assessment for the diagnosis of peripheral arterial disease (PAD) in diabetic foot syndrome (DFS) is poor. Pulse volume recordings (PVRs) at the forefoot level could be a valuable diagnostic tool in the presence of medial arterial calcification. Patients and methods: Patients with DFS who underwent invasive angiography between 01/2020 and 11/2024 and had corresponding PVRs performed within 30 days prior to the procedure were included. DFS was classified according to the Wagner–Armstrong classification. Clinical characteristics and hemodynamic parameters, including systolic ankle pressures and ankle–brachial index were recorded. PVRs were analyzed semiquantitatively by investigators blinded to the clinical information and quantitatively with determination of upstroke time (UST), upstroke ratio (USR), and maximum systolic amplitude (MSA). Angiographic PAD severity was graded according to the GLASS classification. Statistical analysis included univariate significance tests, 2 × 2 contingency tables, receiver–operator characteristic (ROC) analysis and determination of interobserver agreement. Results: In this study, 90 extremities of 70 patients were analyzed, 47 of whom had an ABI ≥ 1.3. Critical limb-threatening ischemia with non-pulsatile PVRs was evident in 6.7%. An abnormal PVR curve morphology (mildly or severely abnormal) yielded a sensitivity and specificity of 63.3% and 85.7% for detection of severe PAD (GLASS stages 2 and 3). Interobserver agreement of semiquantitative PVR rating was substantial (Cohen’s kappa 0.8) in 51 evaluated cases. For detection of any PAD (GLASS ≥ 1) or severe PAD (GLASS ≥ 2), we found the highest diagnostic accuracy for MSA (area under the curve [AUC] 0.89 and 0.82). With a cut-off value of 0.58 mmHg, MSA had a sensitivity of 91.4% and a specificity of 80.8% for detection of any PAD (GLASS ≥ 1). MSA with a cut-off of 0.27 mmHg had a sensitivity of 72.2% and a specificity of 77.1% for detection of severe PAD, whereas the sensitivity and specificity for detection of inframalleolar disease were 62.9% and 69.4%, respectively. Results were consistent in subgroup analyses. Conclusions: PVRs with extraction of quantitative features offer promising diagnostic yield for detection of PAD in the setting of DFS. MSA outperformed UST and USR but showed limited capability of detecting impaired inframalleolar outflow.
Journal Article
Deoxyguanosine kinase mutation F180S is associated with a lean phenotype in mice
by
Spyroglou, Ariadni
,
Beuschlein, Felix
,
Schneider, Holger
in
Abnormalities
,
Adipocytes
,
Adipose tissue
2023
BackgroundDeoxyguanosine kinase (DGUOK) deficiency is one of the genetic causes of mitochondrial DNA depletion syndrome (MDDS) in humans, leading to the hepatocerebral or the isolated hepatic form of MDDS. Mouse models are helpful tools for the improvement of understanding of the pathophysiology of diseases and offer the opportunity to examine new therapeutic options.MethodsHerein, we describe the generation and metabolic characterization of a mouse line carrying a homozygous DguokF180S/F180S mutation derived from an N-ethyl-N-nitrosourea-mutagenesis screen. Energy expenditure (EE), oxygen consumption (VO2) and carbon dioxide production (VCO2) were assessed in metabolic cages. LC-MS/MS was used to quantify plasma adrenal steroids. Plasma insulin and leptin levels were quantified with commercially available assay kits.ResultsMutant animals displayed significantly lower body weights and reduced inguinal fat pad mass, in comparison to unaffected littermates. Biochemically, they were characterized by significantly lower blood glucose levels, accompanied by significantly lower insulin, total cholesterol, high density lipoprotein and triglyceride levels. They also displayed an almost 2-fold increase in transaminases. Moreover, absolute EE was comparable in mutant and control mice, but EE in mutants was uncoupled from their body weights. Histological examination of inguinal white adipose tissue (WAT) revealed adipocytes with multilocular fat droplets reminiscent of WAT browning. In addition, mRNA and protein expression of Ucp1 was increased. Mutant mice also presented differing mitochondrial DNA content in various tissues and altered metabolic activity in mitochondria, but no further phenotypical or behavioral abnormalities. Preliminary data imply normal survival of DguokF180S/F180S mutant animals.ConclusionTaken together, DGUOK mutation F180S leads to a lean phenotype, with lower glucose, insulin, and lipid levels rendering this mouse model not only useful for the study of MDDS forms but also for deciphering mechanisms resulting in a lean phenotype.
Journal Article
Novel role of mechanosensitive AT1B receptors in myogenic vasoconstriction
by
Schneider, Holger
,
Blodow, Stephanie
,
Mederos y Schnitzler, Michael
in
Angiotensin II - metabolism
,
Angiotensinogen - genetics
,
Angiotensinogen - metabolism
2014
Myogenic vasoconstriction is an inherent property of vascular smooth muscle cells (VSMCs) of resistance arteries harboring ill-defined mechanosensing and mechanotransducing elements. G protein-coupled receptors (GPCRs) are discussed as mechanosensors in VSMCs. In this study, we sought to identify and characterize the role and impact of GPCRs on myogenic vasoconstriction. Thus, we analyzed mRNA expression levels of GPCRs in resistance versus preceding conduit arteries revealing a significant enrichment of several GPCRs in resistance vessels. Selective pharmacological blockade of the highly expressed GPCRs in isolated murine mesenteric arteries ex vivo decreased myogenic vasoconstriction. In particular, candesartan and losartan most prominently suppressed myogenic tone, suggesting that AT
1
receptors play a central role in myogenic vasoconstriction. Analyzing angiotensinogen
−/−
mice, a relevant contribution of locally produced angiotensin II to myogenic tone could be excluded. Investigation of AT
1A
−/−
and AT
1B
−/−
murine mesenteric arteries revealed that AT
1B
, but not AT
1A
, receptors are key components of myogenic regulation. This notion was supported by examining fura-2-loaded isolated AT
1A
−/−
and AT
1B
−/−
VSMCs. Our results indicate that in VSMCs, AT
1B
receptors are more mechanosensitive than AT
1A
receptors even at comparable receptor expression levels. Furthermore, we demonstrate that the mechanosensitivity of GPCRs is agonist-independent and positively correlates with receptor expression levels.
Journal Article
SAT297 Major Immunophenotypic Abnormalities In Patients With Primary Adrenal Insufficiency Of Different Etiology
by
Reisch, Nicole
,
Kobold, Sebastian
,
Seiter, Thomas Marchant
in
Adrenal (Excluding Mineralocorticoids)
2023
Disclosure: H.F. Nowotny: None. T. Marchant Seiter: None. J. Ju: None. A. Gottschlich: None. H. Schneider: None. S. Zopp: None. F. Vogel: None. L. Tschaidse: None. M.K. Auer: None. C. Lottspeich: None. S. Kobold: None. S. Rothenfusser: None. F. Beuschlein: None. M. Reincke: None. L. Braun: None. N. Reisch: None. Background: Increased risk of infection, adrenal crises and a higher mortality rate have been reported for patients with primary adrenal insufficiency (PAI). Such dismal outcomes have been inferred to immune cell dysregulation as a consequence of unphysiological cortisol replacement. As the immune landscape of patients with different types of PAI has not been systematically explored, we set out to immunophenotype PAI patients with different causes of glucocorticoid deficiency. Methods: The present cross-sectional single center study includes 28 patients with congenital adrenal hyperplasia (CAH), 27 patients after bilateral adrenalectomy due to Cushing’s syndrome (BADx), 21 patients with Addison’s disease (AD) and 52 healthy controls. All patients with PAI were on a stable glucocorticoid replacement regimen using a median dose of 25 mg hydrocortisone (IQR 5 mg for BADx and AD and IQR 10 mg for CAH) per day. Heparinized blood samples were processed to isolate peripheral blood mononuclear cells. All samples were processed for analysis of immune cell subsets using multicolor flow cytometry after four-hour stimulation with phorbol myristate acetate (PMA)/Ionomycin, as well as analysis of natural killer (NK-) cell cytotoxicity and clock gene expression. Results: Analysis of immune cell profiles revealed reduced percentages of IFNγ-secreting T helper (Th1) in AD (p = 0.0024) and cytotoxic (Tc1) cells in CAH (p = 0.0055) and AD patients (p = 0.0075) compared to controls. Moreover, we observed a downregulation of the percentage of IL-4+ Th2 cells in AD patients (p = 0.0157) and Tc2 cells in AD (p = 0.0154) and CAH patients (p = 0.0012) compared to controls. Th17 and Tc17 cells were also downregulated in patients with AD compared to the other patient groups and controls (p < 0.0001). NK-cell cytotoxicity (NKCC) using bioluminescence measurements was reduced in all subsets of PAI patients compared to controls with the lowest change in patients with CAH (mean specific lysis 57.5% in controls, 21.7% in CAH, -0.5% in AD and -28.7% in BADx). The percentage of activated NK-cells was upregulated in BADx (p = 0.0008) and AD patients (p = 0.0348) compared to controls, also expressed as an increase in CD107a expression as a marker of NK-cell degranulation (BADx p < 0.0001; AD p = 0.0002). While the percentage of NK-cell activating receptor expressing NK-cells did not differ from controls, expression percentage of NK-cell inhibiting receptor CD94 was upregulated in both BADx and AD patients (p < 0.0001). Conclusion: In patients with three different etiologies of PAI, distinct differences in T- and NK-cell-phenotypes became apparent despite the use of same GC preparation and dose. Our results highlight so far unsuspected differences in immune cell composition and NK-cell function in PAI patients of different causes and suggest disease-specific alterations that might necessitate disease-specific treatment. Presentation: Saturday, June 17, 2023
Journal Article