Oxidative Stress in Hypobaric Hypoxia

Oxidative Stress in Hypobaric Hypoxia and Influence on Vessel-tone Modifying Mediators

The trial investigates changes in metabolism during high altitude expedition up to 6865m. A mass-spectrometry based platform is used to detect different oxidative stress related metabolites. Symptoms of acute mountain sickness are evaluated and correlated with laboratory parameters.

Study Overview

• Status: Completed
• Conditions: Acute Mountain Sickness; Oxidative Stress; Hypobaric Hypoxia; Metabolomics
• Intervention / Treatment: Other: Hypoxic exposure

Detailed Description

Background

Altitude related illness, which include acute mountain sickness (AMS), high altitude pulmonary edema (HAPE) and high altitude cerebral edema (HACE), is common in subjects exposed to high altitude during professional or leisure time activities. There are independent risk factors such as: individual susceptibility and rate of ascent. HAPE is a potentially life-threatening complication of high altitude stay, mostly occuring within the first 2-5 days of exposure. Although there is a controversial discussion, excessive hypoxic pulmonary vasoconstriction is thought to be the main trigger for developing HAPE. Beside the controversial discussion if hypobaric hypoxia leads to oxidative stress it is not known whether oxidative stress contributes to AMS or HAPE.

Objective

The investigators hypothesize that reactive oxygen species are generated during high altitude stay and contribute to the development of acute mountain sickness. Furthermore they would like to describe other changes in metabolic pathways possibly contributing to vessel tone dysregulation.

Methods

36 healthy volunteers will examined during an high altitude medical research expedition to Mount Muztagh ata (7549m) in Western China. Acute mountain sickness scores and clinical parameters will be assessed. Metabolomics analysis of more than 390 parameters, using a mass spectrometry-based targeted metabolomic platform, is used to detect systemic oxidative stress and functional impairment of enzymes that require oxidation-sensitive co-factors. Furthermore routine laboratory test will be done, for example CRP, creatinine and interleukines

• Study Type: Interventional
• Enrollment (Actual): 36
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Switzerland
  • Aarau, Switzerland, 5001
    • Center of Laboratory Medicine

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 70 years (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• healthy
• physical fit
• mountaineering experience
• 18-70 years

Exclusion Criteria

• any type of disease
• regular intake of medicaments
• history of high altitude pulmonary edema
• severe acute mountain sickness below an altitude of 3500m
• any history of high altitude cerebral edema

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
Number of volunteers with acute mountain sickness	during ascent, expected to be approximately 19-23 days

Secondary Outcome Measures

Outcome Measure	Time Frame
Change from baseline in oxygen saturation in blood	during ascent, expected to be approximately 19-23 days
Changes from baseline in oxidative stress	during ascent, expected to be approximately 19-23 days
Changes from baseline in different metabolic pathways	during ascent, expected to be approximately 19-23 days

Collaborators and Investigators

• Sponsor: University Hospital Inselspital, Berne
• Collaborators: Swiss National Science Foundation; Kantonsspital Aarau
• Investigators: Study Chair: Andreas Huber, Prof. Dr. med., Center of Laboratory Medicine, Cantonal Hospital Aarau, 5001 Aarau

Study record dates

Study Major Dates

• Study Start: March 1, 2005
• Primary Completion (Actual): December 1, 2005
• Study Completion (Actual): February 1, 2010

Study Registration Dates

• First Submitted: September 14, 2011
• First Submitted That Met QC Criteria: September 16, 2011
• First Posted (Estimate): September 19, 2011

Study Record Updates

• Last Update Posted (Estimate): September 21, 2011
• Last Update Submitted That Met QC Criteria: September 20, 2011
• Last Verified: September 1, 2011

More Information

Terms related to this study

• Keywords: oxidative stress; metabolomics; hypobaric hypoxia; acute mountain sickness; high altitude
• Additional Relevant MeSH Terms: Respiratory Tract Diseases; Respiration Disorders; Signs and Symptoms, Respiratory; Altitude Sickness; Hypoxia
• Other Study ID Numbers: KEK 1189; SNSF 3200B0-108300