0000000000174783

AUTHOR

Friedrich C. Luft

Adaptive physiological water conservation explains hypertension and muscle catabolism in experimental chronic renal failure

Abstract Aim We have reported earlier that a high salt intake triggered an aestivation‐like natriuretic‐ureotelic body water conservation response that lowered muscle mass and increased blood pressure. Here, we tested the hypothesis that a similar adaptive water conservation response occurs in experimental chronic renal failure. Methods In four subsequent experiments in Sprague Dawley rats, we used surgical 5/6 renal mass reduction (5/6 Nx) to induce chronic renal failure. We studied solute and water excretion in 24‐hour metabolic cage experiments, chronic blood pressure by radiotelemetry, chronic metabolic adjustment in liver and skeletal muscle by metabolomics and selected enzyme activity…

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Aestivation Motifs Explain Hypertension and Muscle Catabolism in Experimental Chronic Renal Failure

Chronic renal failure leads to muscle mass loss and hypertension, which according to textbook teaching occur secondary to an inability of the kidneys to excrete solutes and water. We found instead that rats with experimental chronic renal failure constantly lost body water, because their kidneys could not sufficiently concentrate the urine. Physiological adaptation to body water loss, termed aestivation, is an evolutionary conserved survival strategy that relies on complex physiologic-metabolic adjustment across multiple organs to prevent otherwise lethal dehydration. We show that rats with chronic renal failure utilize these ancient water conservation motifs to successfully stabilize their…

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Skin Sodium Accumulates in Psoriasis and Reflects Disease Severity

Sodium can accumulate in the skin at concentrations exceeding serum levels. A high sodium environment can lead to pathogenic T helper 17 cell expansion. Psoriasis is a chronic inflammatory skin disease in which IL-17. producing T helper 17 cells play a crucial role. In an observational study, we measured skin sodium content in patients with psoriasis and in age-matched healthy controls by Sodium-23 magnetic resonance imaging. Patients with PASI > 5 showed significantly higher sodium and water content in the skin but not in other tissues than those with lower PASI or healthy controls. Skin sodium concentrations measured by Sodium-23 spectroscopy or by atomic absorption spectrometry in ashed-…

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European Society of Hypertension Working Group on Obesity: background, aims and perspectives.

Clinica Medica, University ofMilano-Bicocca, Ospedale San Gerardo, Monza, Milan, ItalyCorrespondence and requests for reprints to Professor Jens Jordan, ChairmanWorking Group on Obesity, Franz Volhard Clinical Research Center, HELIOSKlinikum Berlin and Medical Faculty of the Charite´, Wiltbergstrase 50, 13125Berlin, GermanyTel: +49 30 9417 2220; fax: +49 30 9417 2265; e-mail: jens.jordan@charite.de

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Aestivation motifs explain hypertension and muscle mass loss in mice with psoriatic skin barrier defect

Aim Recent evidence suggests that arterial hypertension could be alternatively explained as a physiological adaptation response to water shortage, termed aestivation, which relies on complex multi-organ metabolic adjustments to prevent dehydration. Here, we tested the hypothesis that chronic water loss across diseased skin leads to similar adaptive water conservation responses as observed in experimental renal failure or high salt diet. Methods We studied mice with keratinocyte-specific overexpression of IL-17A which develop severe psoriasis-like skin disease. We measured transepidermal water loss and solute and water excretion in the urine. We quantified glomerular filtration rate (GFR) by…

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Sequence-based bioinformatic prediction and QUASEP identify genomic imprinting of the KCNK9 potassium channel gene in mouse and human

Genomic imprinting is the epigenetic marking of gene subsets resulting in monoallelic or predominant expression of one of the two parental alleles according to their parental origin. We describe the systematic experimental verification of a prioritized 16 candidate imprinted gene set predicted by sequence-based bioinformatic analyses. We used Quantification of Allele-Specific Expression by Pyrosequencing (QUASEP) and discovered maternal-specific imprinted expression of the Kcnk9 gene as well as strain-dependent preferential expression of the Rarres1 gene in E11.5 (C57BL/6 3 Cast/Ei)F1 and informative (C57BL/6 3 Cast/ Ei) 3 C57BL/6 backcross mouse embryos. For the remaining 14 candidate impr…

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Influence of St John's wort on catecholamine turnover and cardiovascular regulation in humans

BACKGROUND: St John's wort (Hypericum perforatum) is a popular over-the-counter antidepressant. Its antidepressive effect has been attributed in part to inhibition of monoamine transporters and monoamine oxidase, on the basis of in vitro studies. METHODS: In a double-blind, randomized, placebo-controlled, crossover study, 16 healthy subjects (11 men and 5 women; mean age, 31 +/- 5 years) ingested either St John's wort (300 mg three times daily) or placebo for 7 days. Imipramine treatment (50 mg three times daily) in 7 subjects served as a positive control. After treatment, physiologic and biochemical tests included cardiovascular reflex testing, graded head-up tilt testing, and plasma catec…

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