PMID- 38093907 OWN - NLM STAT- PubMed-not-MEDLINE LR - 20231214 IS - 1664-042X (Print) IS - 1664-042X (Electronic) IS - 1664-042X (Linking) VI - 14 DP - 2023 TI - Asymmetric and symmetric dimethylarginine in high altitude pulmonary hypertension (HAPH) and high altitude pulmonary edema (HAPE). PG - 1297636 LID - 10.3389/fphys.2023.1297636 [doi] LID - 1297636 AB - Introduction: High altitude exposure may lead to high altitude pulmonary hypertension (HAPH) and high altitude pulmonary edema (HAPE). The pathophysiologic processes of both entities have been linked to decreased nitric oxide (NO) availability. Methods: We studied the effect of acute high altitude exposure on the plasma concentrations of asymmetric (ADMA) and symmetric dimethylarginine (SDMA), L-arginine, L-ornithine, and L-citrulline in two independent studies. We further investigated whether these biomarkers involved in NO metabolism were related to HAPH and HAPE, respectively. Fifty (study A) and thirteen (study B) non-acclimatized lowlanders were exposed to 4,559 m for 44 and 67 h, respectively. In contrast to study A, the participants in study B were characterized by a history of at least one episode of HAPE. Arterial blood gases and biomarker concentrations in venous plasma were assessed at low altitude (baseline) and repeatedly at high altitude. HAPE was diagnosed by chest radiography, and HAPH by measuring right ventricular to atrial pressure gradient (RVPG) with transthoracic echocardiography. AMS was evaluated with the Lake Louise Score (LLS) and the AMS-C score. Results: In both studies SDMA concentration significantly increased at high altitude. ADMA baseline concentrations were higher in individuals with HAPE susceptibility (study B) compared to those without (study A). However, upon high altitude exposure ADMA only increased in individuals without HAPE susceptibility, while there was no further increase in those with HAPE susceptibility. We observed an acute and transient decrease of L-ornithine and a more delayed but prolonged reduction of L-citrulline during high altitude exposure. In both studies SDMA positively correlated and L-ornithine negatively correlated with RVPG. ADMA was significantly associated with the occurrence of HAPE (study B). ADMA and SDMA were inversely correlated with alveolar PO(2), while L-ornithine was inversely correlated with blood oxygenation and haemoglobin levels, respectively. Discussion: In non-acclimatized individuals ADMA and SDMA, two biomarkers decreasing endothelial NO production, increased after acute exposure to 4,559 m. The observed biomarker changes suggest that both NO synthesis and arginase pathways are involved in the pathophysiology of HAPH and HAPE. CI - Copyright (c) 2023 Hannemann, Freytag, Schiefer, Macholz, Sareban, Schmidt-Hutten, Stang, Schwedhelm, Swenson, Boger and Berger. FAU - Hannemann, Juliane AU - Hannemann J AD - Institute of Clinical Pharmacology and Toxicology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany. AD - Institute DECIPHER, German-Chilean Institute for Research on Pulmonary Hypoxia and its Health Sequelae, Hamburg, Germany. FAU - Freytag, Julius AU - Freytag J AD - Department of Anesthesiology and Intensive Care Medicine, University Hospital Essen, University Duisburg-Essen, Essen, Germany. FAU - Schiefer, Lisa Maria AU - Schiefer LM AD - Paracelsus Medical University Salzburg, Salzburg, Austria. FAU - Macholz, Franziska AU - Macholz F AD - Department of Anesthesiology, Critical Care and Pain Medicine, Paracelsus Medical University, Salzburg, Austria. FAU - Sareban, Mahdi AU - Sareban M AD - University Institute of Sports Medicine, Prevention and Rehabilitation and Research Institute of Molecular Sports Medicine and Rehabilitation, Paracelsus Medical University, Salzburg, Austria. FAU - Schmidt-Hutten, Lena AU - Schmidt-Hutten L AD - Institute of Clinical Pharmacology and Toxicology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany. FAU - Stang, Heike AU - Stang H AD - Institute of Clinical Pharmacology and Toxicology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany. FAU - Schwedhelm, Edzard AU - Schwedhelm E AD - Institute of Clinical Pharmacology and Toxicology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany. FAU - Swenson, Erik R AU - Swenson ER AD - Division of Pulmonary, Critical Care and Sleep Medicine, VA Puget Sound Health Care System, University of Washington, Seattle, WA, United States. FAU - Boger, Rainer AU - Boger R AD - Institute of Clinical Pharmacology and Toxicology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany. AD - Institute DECIPHER, German-Chilean Institute for Research on Pulmonary Hypoxia and its Health Sequelae, Hamburg, Germany. FAU - Berger, Marc Moritz AU - Berger MM AD - Department of Anesthesiology and Intensive Care Medicine, University Hospital Essen, University Duisburg-Essen, Essen, Germany. LA - eng PT - Journal Article DEP - 20231129 PL - Switzerland TA - Front Physiol JT - Frontiers in physiology JID - 101549006 PMC - PMC10716225 OTO - NOTNLM OT - ADMA (asymmetric dimethyl arginine) OT - NO OT - biomarker OT - high altitude OT - hypoxia OT - nitric oxide COIS- The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. EDAT- 2023/12/14 06:42 MHDA- 2023/12/14 06:43 PMCR- 2023/11/29 CRDT- 2023/12/14 04:02 PHST- 2023/09/21 00:00 [received] PHST- 2023/11/20 00:00 [accepted] PHST- 2023/12/14 06:43 [medline] PHST- 2023/12/14 06:42 [pubmed] PHST- 2023/12/14 04:02 [entrez] PHST- 2023/11/29 00:00 [pmc-release] AID - 1297636 [pii] AID - 10.3389/fphys.2023.1297636 [doi] PST - epublish SO - Front Physiol. 2023 Nov 29;14:1297636. doi: 10.3389/fphys.2023.1297636. eCollection 2023.