Publications by authors named "Klara Meyer"

3 Publications

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Hyperstable arousal regulation in multiple sclerosis.

Psychoneuroendocrinology 2019 12 28;110:104417. Epub 2019 Aug 28.

Department of Neurology, University of Leipzig, Germany; Translational Centre for Regenerative Medicine, University of Leipzig, Germany. Electronic address:

Background: Fatigue is common in multiple sclerosis (MS) patients. Exhaustion of physiological reserves and mental stress are postulated causes, the latter supported by more pronounced hypothalamic-pituitary-adrenal (HPA) axis activation in fatigued patients. Divergent dysregulation of arousal appears to play important roles in depression- (hyperstable arousal) and in cancer-related (unstable arousal) fatigue, where HPA axis is hyperactive or hypoactive, respectively.

Objective: This study assessed arousal regulation in multiple sclerosis patients, explored if fatigue can be physiologically described by altered arousal regulation, and if HPA axis activity corresponds to the type(s) of arousal regulation.

Methods: 51 mildly-affected patients with relapsing-remitting MS (86% on disease-modifying treatment) and 20 healthy controls were analysed via Vigilance Algorithm Leipzig and combined dexamethasone/corticotropin releasing hormone test.

Results: Hyperstable arousal pattern was significantly more frequent in patients than in controls (62.7% vs. 45.0%, p = 0.011). Patients scored higher on all fatigue, but not on sleepiness scales. All patients combined showed mild activation of the hypothalamic-pituitary-adrenal axis (p < 0.05 for post-CRH ACTH and AUC ACTH; cortisol n.s.). While fatigue was numerically more pronounced in both hyperstable and unstable arousal, HPA axis activity was highest in hyperstable and lowest in unstable arousal (p = 0.013 for post-CRH ACTH; p = 0.087 for AUC ACTH; cortisol n.s.).

Conclusion: Frequency of arousal patterns are altered in MS. An association with HPA axis activity was weak, possibly because the present sample was stable on immunotherapy.
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http://dx.doi.org/10.1016/j.psyneuen.2019.104417DOI Listing
December 2019

Central noradrenaline transporter availability is linked with HPA axis responsiveness and copeptin in human obesity and non-obese controls.

Stress 2019 01 29;22(1):93-102. Epub 2018 Oct 29.

a Integrated Research and Treatment Center (IFB) Adiposity Diseases , Leipzig University Medical Center , Leipzig , Germany.

The central noradrenaline (NA) stress-response network co-mediates hypothalamic-pituitary-adrenal (HPA) axis activation and arginine-vasopressin (AVP) release. Dysregulation of these systems contributes to stress-related diseases such as human obesity, but their interrelation remains unclear. The study was aimed to test for the first time in vivo whether central noradrenergic activity quantitatively indexed by the availability of the presynaptic NA transporter (NAT) is associated with HPA axis responsiveness as measured with the combined dexamethasone suppression/corticotropin releasing hormone stimulation (dex/CRH) test and copeptin as a surrogate marker of the serum AVP tone in highly obese, otherwise, healthy individuals compared to age- and sex-matched non-obese, healthy controls. In order to assess central NAT availability, positron emission tomography (PET) was applied using the NAT-selective radiotracer S,S-[C]O-methylreboxetine (MRB) and correlated with curve indicators derived from the dex/CRH test (maximum, MAX, and area under the curve, AUC, for cortisol and adrenocorticotropic hormone, ACTH) as well as with copeptin. In non-obese controls, positive correlations were found between the NAT distribution volume ratios (DVR) of the orbitofrontal cortex (OFC) and the amygdala with the HPA response (OFC: ACTH r = 0.87, p = .001; cortisol r = 0.86, p = .002; amygdala: ACTH r = 0.86, p = .002; cortisol r = 0.79, p = .006), while in obesity, the hypothalamic DVR correlated inversely with the HPA axis response (cortisol, r = -0.66, p = .04) and with copeptin (r = -0.71, p = .02). This association of central NAT availability with HPA axis responsiveness and copeptin suggests a mechanistic interaction between noradrenergic transmission with HPA axis activity and the serum AVP system that differs between non-obese individuals with prefrontal-limbic involvement and obesity with a hypothalamic-centered relationship. Whether the latter finding contributes to obesogenic behavior needs to be further explored.
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http://dx.doi.org/10.1080/10253890.2018.1511698DOI Listing
January 2019

Post-dexamethasone serum copeptin corresponds to HPA axis responsiveness in human obesity.

Psychoneuroendocrinology 2017 04 16;78:39-47. Epub 2017 Jan 16.

Department of Neurology, University of Leipzig, Leipzig, Germany; Translational Centre for Regenerative Medicine, University of Leipzig, Leipzig, Germany. Electronic address:

Context: Increased activities of the arginine-vasopressin (AVP) system and the hypothalamic-pituitary-adrenal (HPA) axis were shown to be associated with human obesity, but relationships between these systems in obesity remain unclear.

Objectives: To assess HPA axis responsiveness and its relation to serum concentrations of the AVP-surrogate copeptin in subjects with obesity (OB) in comparison to non-obesity controls (NOC).

Methods: In a cross-sectional monocentric study, thirty-nine OB (f/m 25/14; age 36.5±10.0years; body mass index, BMI, 41.5±4.7kg/m) were compared to twenty-two NOC (f/m 12/10; age 35.3±8.5years; BMI 23.1±2.4kg/m), matched for age and sex. All individuals underwent the combined dexamethasone/CRH test.

Main Outcome Measures: Plasma ACTH and cortisol curve indicators derived from the dex/CRH test (post-CRH concentrations 30min after 100μg CRH; maximum concentration, MAX; area-under-the-curve, AUC; ACTH/cortisol ratios). Copeptin was assessed in 1500h samples of the dex/CRH test (after 1.5mg of oral dexamethasone, prior to CRH administration).

Results: Copeptin serum concentrations were higher in OB (median [IQR]: OB 4.62 [2.60-5.88] vs. NOC 3.04 [2.52-4.29] pmol/l, P=0.04). Correspondingly, OB showed higher post-CRH cortisol concentrations (OB: 51.5 [25.9-159.3] vs. NOC: 28.6 [20.0-41.6] nmol/l, P=0.01) and a lower post-CRH ACTH/cortisol ratio (OB: 0.028 [0.016-0.053] vs. NOC: 0.048 [0.034-0.070] pmol/nmol, P<0.01). Serum copeptin was significantly associated with HPA responsiveness in OB (post-CRH ACTH: R=0.42, P<0.01), driven by OB men (post-CRH ACTH: R=0.76, P<0.01, post-CRH cortisol: R=0.64, P=0.02). All associations withstand adjustments for BMI and age.

Conclusions: The association between increased copeptin with ACTH and cortisol release suggests a potential mechanistic interaction of the AVP system with HPA activation in human obesity. The relation of copeptin and HPA responsiveness should be further validated in situations with pronounced HPA activation, such as depression or multiple sclerosis.
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http://dx.doi.org/10.1016/j.psyneuen.2017.01.004DOI Listing
April 2017