Effects of Oxygen Status on Endotoxemia Induced Inflammation and Hypoxia Inducible Factor-1α

Sponsor

Radboud University Medical Center (Other)

Overall Status

Completed

CT.gov ID

NCT01978158

Collaborator

(none)

Enrollment

Location

Arms

Duration (Months)

Patients Per Site Per Month

Study Details

Study Description

Brief Summary

Oxygen is a widely available gas that is cheap, easy to get and extensively used in medicine. From animal studies it has become apparent that increasing or lowering the degree of oxygen in the blood, the inflammatory response can be altered. We will investigate of this is also true in humans by increasing, lowering or keeping oxygen levels normal while giving healthy subjects a short inflammatory stimulus.

Condition or Disease	Intervention/Treatment	Phase
Hypoxia Normoxia Hyperoxia	Drug: Lipopolysaccharide	Phase 1/Phase 2

Detailed Description

The primary objective of the study is to determine the effects of hyperoxia and hypoxia compared to normoxia in the human endotoxemia model on the innate immune reponse in healthy volunteers.

A parallel, randomized study in healthy male volunteers. The subjects will be randomized to hypoxia, hyperoxia, or normoxia, and will all undergo experimental human endotoxemia (administration of 2 ng/kg LPS iv).

In the hypoxia group: the subjects will breathe an individualized mix of nitrogen and room air for 3.5 hours using an air-tight respiratory helmet. The gas mixture will be adjusted to achieve a saturation of 80-85%. In the hyperoxia group, subjects will breathe 100% oxygen for 3.5 hours using the same respiratory helmet. In the normoxia group, subjects will breathe room air (21% oxygen, 79% nitrogen) also wearing the respiratory helmet. 1 hour after oxygen status adjustment (t=0), all subject will be administered an intravenous bolus (2ng/kg) of LPS derived from E coli O:113. 2.5 hours after LPS administration, the helmets will be removed and all subjects will breathe ambient room air.

The primary study endpoint is the difference in plasma cytokines between the hypoxia and normoxia group, and between the hyperoxia and normoxia group. Secondary objectives include HIF-1α protein and mRNA, aHIF mRNA expression in circulating leukocytes, measures of ROS, leukocyte phagocytosis, and cytokine production by leukocytes stimulated ex vivo with various inflammatory stimuli, and measurement of basic hemodynamic and ventilatory parameters and temperature.

Study Design

Study Type:

Interventional

Actual Enrollment :

30 participants

Allocation:

Randomized

Intervention Model:

Parallel Assignment

Masking:

None (Open Label)

Primary Purpose:

Treatment

Official Title:

Effects of Oxygen Status on Endotoxemia Induced Inflammation and Hypoxia Inducible Factor-1α. A Pilot Proof of Principle Study

Study Start Date :

Oct 1, 2013

Actual Primary Completion Date :

Dec 1, 2013

Actual Study Completion Date :

Dec 1, 2013

Arms and Interventions

Arm	Intervention/Treatment
Experimental: Hypoxia Subjects will be breathing an individualized mix of nitrogen and room air titrated to an oxygen saturation of 80-85%.	Drug: Lipopolysaccharide LPS is used to elicit an inflammatory response in all subjects Other Names: Purified LPS from Escherischa coli (O:113)
Experimental: Hyperoxia Subjects will be breathing 100% of oxygen	Drug: Lipopolysaccharide LPS is used to elicit an inflammatory response in all subjects Other Names: Purified LPS from Escherischa coli (O:113)
Active Comparator: Normoxia Subjects wil be breathing room air (21%)	Drug: Lipopolysaccharide LPS is used to elicit an inflammatory response in all subjects Other Names: Purified LPS from Escherischa coli (O:113)

Arm

Intervention/Treatment

Experimental: Hypoxia

Subjects will be breathing an individualized mix of nitrogen and room air titrated to an oxygen saturation of 80-85%.

Drug: Lipopolysaccharide

LPS is used to elicit an inflammatory response in all subjects

Other Names:

Purified LPS from Escherischa coli (O:113)

Experimental: Hyperoxia

Subjects will be breathing 100% of oxygen

Drug: Lipopolysaccharide

LPS is used to elicit an inflammatory response in all subjects

Other Names:

Purified LPS from Escherischa coli (O:113)

Active Comparator: Normoxia

Subjects wil be breathing room air (21%)

Drug: Lipopolysaccharide

LPS is used to elicit an inflammatory response in all subjects

Other Names:

Purified LPS from Escherischa coli (O:113)

Outcome Measures

Primary Outcome Measures

Plasma TNF-alpha concentration following LPS administration [1 day]
Plasma TNF-α concentration after LPS administration (Area Under Curve); comparison of subjects treated with hypoxia compared to normoxia and hyperoxia compared to hypoxia

Secondary Outcome Measures

Hypoxia Inducible Factor 1 alpha in circulating leukocytes [1 day]
Hypoxia Inducible Factor 1 alpha in circulating neutrophils, lymfocytes and monocytes as measured with flow cytometry
Hypoxia Inducible Factor mRNA and anti Hypoxia Inducible Factor mRNA in circulating leukocytes [24 hours]
Reactive Oxygen Species in circulating leukocytes [1 day]
Phagocytic function of circulating leukocytes [1 day]
cytokine production after ex vivo stimulation of leukocytes [1 day]
circulating cytokines (including but not limited to IL-6, IL-10, IL-1RA) [1 day]
Hemodynamic parameters [1 day]
Blood pressure, heart frequency, cardiac output measurement
ventilatory response [1 day]
Measures of ventilation: respiratory rate, blood gas changes
adenosine metabolism [1 day]
urine and plasma adenosine,adenosine receptor mRNA, purines
alkaline phosphatase [1 day]
cognitive function [1 day]
neuropsychologic assessment of cognitive function
Hepcidin and iron parameters [1 day]
catecholamines and cortisol [1 day]
adrenaline, noradrenaline, dopamine and cortisol
Neutrophilic function [1 day]
body temperature [1 day]
oxygen saturation and arterial blood gas [1]
subjective symptom scores [1 day]
high sensitive troponine [1 day]
iFABP [1 day]
brain specific proteins [1 day]
endocan [1 day]
downstream targets of HIF [1 day]
adrenomedullin, VEGF, EPO
heart rate variability [1 day]
kidney injury markers in plasma and urine [2 days]
microbiome in feces [-1 day untill 1 week]
markers of immunoparalysis [1 day]
monocytic histone 3 lysine 4 trimethylation of the promotor region of pro-inflammatory genes, ex viv production of proinflammatory cytokines, HLA-DR expression on moncytes.
measures of coagulation and plateletfunction [1 day]
platelet activation and platelet function, thrombin generation and other coagulation parameters, hematolocial infection profile using hematology analyser
meausures of coagulation and fibrinolysis [1 day]
thrombin generation, thrombocyte function, ROTEM, plasmatic coagulation, fibrinolysis parameters

Eligibility Criteria

Criteria

Ages Eligible for Study:

18 Years to 35 Years

Sexes Eligible for Study:

Male

Accepts Healthy Volunteers:

Yes

Inclusion Criteria:

Written informed consent to participate in this trial
Male subjects aged 18 to 35 years inclusive
Healthy as determined by medical history, physical examination, vital signs, 12-lead electrocardiogram, and clinical laboratory parameters

Exclusion Criteria:

Use of any medication(including herbal remedies and vitamin/mineral supplements) or recreational drugs within 7 days prior to profiling day
Smoking
Use of caffeine, or alcohol or within 1 day prior to profiling day
Previous participation in a trial where LPS was administered
Surgery or trauma with significant blood loss or blood donation within 3 months prior to profiling day
Participation in another clinical trial within 3 months prior to profiling day.
History, signs or symptoms of cardiovascular disease
An implant that in the opinion of the investigator may make invasive procedures risky for the subject due to the increased risks associated with a possible infection.
Subject has an implanted active cardiac device (ICD, IPG and/or CRT) Implanted active neurostimulation device
Subject has internal jugular vein that cannot be accessed
History of vaso-vagal collapse or of orthostatic hypotension
History of atrial or ventricular arrhythmia
Resting pulse rate ≤45 or ≥100 beats / min
Hypertension (RR systolic >160 or RR diastolic >90)
Hypotension (RR systolic <100 or RR diastolic <50)
Conduction abnormalities on the ECG consisting of a 1st degree atrioventricular block or a complex bundle branch block
Subject is diagnosed with epilepsy or history of seizures
Renal impairment: plasma creatinine >120 μmol/L
Liver function abnormality: alkaline phosphatase>230 U/L and/or ALT>90 U/L
Coagulation abnormalities: APTT or PT > 1.5 times the reference range
History of asthma
Immuno-deficiency CRP > 20 mg/L, WBC > 12x109/L, or clinically significant acute illness, including infections, within 2 weeks before profiling day
Known or suspected of not being able to comply with the trial protocol - Inability to personally provide written informed consent (e.g. for linguistic or mental reasons) and/or take part in the study.