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Effect of Antioxidants on Ocular Blood Flow, Endothelial Function, and Cytokine Levels in LPS Induced Inflammatory Model in Humans.

Phase 4
Completed
Conditions
Retina
Regional Blood Flow
Endotoxin, Escherichia Coli
Interventions
Drug: vitamin and mineral supplement
Drug: Escherichia coli Endotoxin (LPS)
Drug: 100% O2
Registration Number
NCT00431691
Lead Sponsor
Medical University of Vienna
Brief Summary

Oxidative stress, which refers to cellular damage caused by reactive oxygen intermediates, has been implicated in many disease processes, especially age-related disorders. Many trials investigating use of antioxidants in protecting different tissues against oxidative stress have been conducted, but the results are ambiguous.

Inflammation is generally associated with enhanced oxidative stress and widespread endothelial dysfunction. 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 inflammatory response in humans. The assessment of outcome parameters will include measurements of ocular blood flow, forearm blood flow and plasma concentration of cytokines. Measurements of ocular hemodynamics provide an unique chance to investigate local blood flow in humans non-invasively. Moreover, the retina is especially susceptible to oxidative stress because of its high consumption of oxygen, its high polyunsaturated fatty acid content, and its exposure to visible light. Evidence from literature clearly supports a role for oxidative stress in pathophysiology of several ocular diseases including diabetic retinopathy and age-related macular degeneration. To investigate the retinal vascular reactivity we will use systemic hyperoxia as a stimulus. The measurement of forearm blood flow will be use to assess endothelial function. The main study objective is to investigate the effect of oral vitamins and minerals supplementation on impaired retinal vascular reactivity after LPS administration.

Detailed Description

Not available

Recruitment & Eligibility

Status
COMPLETED
Sex
Male
Target Recruitment
22
Inclusion Criteria
  • Men aged between 18 and 35 years, nonsmokers
  • Body mass index between 15th and 85th percentile
  • 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

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
1vitamin and mineral supplement-
1Escherichia coli Endotoxin (LPS)-
1100% O2-
2Escherichia coli Endotoxin (LPS)-
2100% O2-
1nitroglycerin-
2nitroglycerin-
Primary Outcome Measures
NameTimeMethod
Retinal blood flowin total 8x on 2 study days
Secondary Outcome Measures
NameTimeMethod
Choroidal blood flowin total 4x on 2 study days
Flow mediated dilation (FMD) of brachial artery assessed with ultrasoundin total 4x on 2 study days
Blood pressure, heart rateon 2 study days
Body temperatureon 2 study days
Concentration of cytokines in plasmaon 2 study days

Trial Locations

Locations (1)

Department of Clinical Pharmacology, Medical University of Vienna

🇦🇹

Vienna, Austria

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