Clinical trial NCT00914576: Effect of Antioxidants on Oxygen Induced Vasoconstriction in Lipopolysaccharide (LPS) Induced Inflammatory Model in Humans
Official title: Effect of Antioxidants on Oxygen Induced Vasoconstriction in LPS Induced Inflammatory Model in Humans
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Healthy
Keywords: Endotoxin, Escherichia Coli
Retina
Regional Blood Flow
Lead sponsor: Medical University of Vienna
Sponsor class: OTHER
First posted: 2009-06-05
Enrollment: 40
Sex: MALE
Minimum age (years): 18
Maximum age (years): 35
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: BASIC_SCIENCE

Brief summary: Oxidative stress has been implicated in playing a pathogenic role in many disease processes, especially in age-related disorders. It has been hypothesized that antioxidative agents such as vitamins and minerals, which are capable of scavenging free radicals, may reduce oxidative stress and may, in turn, be beneficial for patients with age-related disorders. Based on this hypothesis, several different combinations of vitamins have been introduced, all targeting at reducing oxidative stress. However, the in-vivo determination of the antioxidative properties of a certain drug or vitamin combination are hard to determine. In the current study, the researchers propose to investigate the effect of VITAMAC®, a combination of vitamins and minerals, in a systemic in-vivo inflammation model.

In the present study, the infusion of LPS, which is a cell wall component of Gram-negative bacteria and a major mediator in the pathogenesis of septic shock, will be used as a standardized experimental model of systemic inflammation in humans. Given that inflammation is associated with enhanced oxidative stress and widespread endothelial dysfunction, the LPS model is well suitable for determination of the antioxidative effects of VITAMAC®. As a main outcome parameter, the vascular reactivity of retinal vessels to systemic hyperoxia (induced by breathing 100% oxygen) will be tested in presence or absence of the antioxidant combination.


Eligibility criteria: Inclusion Criteria:

* Men aged between 18 and 35 years, nonsmokers
* Body mass index between 15th and 85th percentile (Must et al. 1991)
* Normal findings in the medical history and physical examination unless the investigator considers an abnormality to be clinically irrelevant
* Normal laboratory values unless the investigator considers an abnormality to be clinically irrelevant
* Normal ophthalmic findings, ametropia \< 3 Dpt

Exclusion Criteria:

* Regular use of medication, abuse of alcoholic beverages, participation in a clinical trial in the 3 weeks preceding the study
* Treatment in the previous 3 weeks with any drug, vitamins and minerals supplements as well
* Symptoms of a clinically relevant illness in the 3 weeks before the first study day
* History of hypersensitivity to the trial drug or to drugs with a similar chemical structure
* History or presence of gastrointestinal, liver or kidney disease, or other conditions known to interfere with, distribution, metabolism or excretion of study drugs
* Blood donation during the previous 3 weeks

Primary outcomes:
measure: Retinal blood flow
timeFrame: 1 year
Secondary outcomes:
Other outcomes:
Locations:
city: Vienna
country: Austria
facility: Department of Clinical Pharmacology, Medical University of Vienna
Study officials:
affiliation: Department of Clinical Pharmacology, Medical University of Vienna
name: Gerhard Garhofer, MD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Told R, Schmidl D, Palkovits S, Boltz A, Gouya G, Wolzt M, Witkowska KJ, Popa-Cherecheanu A, Werkmeister RM, Garhofer G, Schmetterer L. Antioxidative capacity of a dietary supplement on retinal hemodynamic function in a human lipopolysaccharide (LPS) model. Invest Ophthalmol Vis Sci. 2014 Dec 18;56(1):403-11. doi: 10.1167/iovs.14-15581.
citation: Told R, Palkovits S, Schmidl D, Boltz A, Gouya G, Wolzt M, Napora KJ, Werkmeister RM, Popa-Cherecheanu A, Garhofer G, Schmetterer L. Retinal hemodynamic effects of antioxidant supplementation in an endotoxin-induced model of oxidative stress in humans. Invest Ophthalmol Vis Sci. 2014 Apr 7;55(4):2220-7. doi: 10.1167/iovs.13-13784.