A Pilot Trial Assessing the Effect of Pomegranate Juice and Extract on Biomarkers of Oxidative Stress, Systemic Inflammation, and Monocyte Function in Hemodialysis Patients
Trial Snapshot
- Phase
- Not Applicable
- Status
- Completed
- Sponsor
- University of Washington
- Enrollment
- 24
- Locations
- 2
- Primary Endpoint
- Markers of endothelial function
Study Overview
Brief Summary
In this study, the investigators will administer pomegranate juice or fruit extract as a targeted antioxidant therapy to hemodialysis patients.
The investigators will examine whether these pomegranate products will be safe and well-tolerated. The investigators will also examine whether these products may lead to improvements in blood serum biomarkers of:
- oxidative stress status
- inflammatory status
- endothelial dysfunction
Detailed Description
There are currently more than 400,000 patients receiving chronic dialysis therapy in the United States. Cardiovascular and infectious diseases are the leading causes of death in hemodialysis patients, accounting for over 50% of all-cause mortality.
There is a complex interaction of inflammation, oxidative stress, and endothelial dysfunction in contributing to cardiovascular and infectious risk in dialysis patients. Since there is much evidence that an increase in oxidative stress contributes to risk of disease in dialysis patients, it is logical to hypothesize the antioxidant therapy may be beneficial in reducing these risks.
In addition to vitamins C and E, the most common and active antioxidant compounds that occur naturally in foods are flavonoids. Dietary flavonoids are highly bioavailable, and have been shown to confer antioxidant protection, inhibit platelet activation, exert vasorelaxant effects, and reduce inflammation in human studies. In animal model studies, dietary flavonoids have been shown to reduce the development of atherosclerosis. Polyphenols also have potent antibacterial, antifungal, and antiviral activities.
Pomegranate juice is a rich source of potent phenolic antioxidants, which have been demonstrated to have anti-atherogenic and vasorelaxant properties. Pomegranate derived polyphenols have also been demonstrated to inhibit platelet activation.
Although available data are limited, several studies suggest that dietary phenols may have beneficial effects in patients undergoing dialysis treatment. These include improvements in lipoprotein profiles, reductions in circulating inflammatory and oxidative stress biomarkers, reductions in infectious complications, and improvements in inflammatory biomarkers. These observations, though limited, suggest that polyphenol based supplementation strategies may be effective in reducing complications in those undergoing dialysis treatment.
Study Design
- Study Type
- Interventional
- Allocation
- Randomized
- Intervention Model
- Crossover
- Primary Purpose
- Prevention
- Masking
- None
Eligibility Criteria
- Ages
- 18 Years to 85 Years (Adult, Older Adult)
- Sex
- All
- Accepts Healthy Volunteers
- No
Inclusion Criteria
- •Patients with end-stage renal disease receiving thrice weekly hemodialysis
- •Age > 18 or < 85 years
- •Life expectancy greater than one year
- •Ability to understand and provide informed consent for participation in the study
Exclusion Criteria
- •History of poor adherence to hemodialysis or medical regimen
- •Prisoners, patients with significant mental illness, and other vulnerable populations
- •AIDS (HIV seropositivity is not an exclusion criteria)
- •Active malignancy excluding basal cell carcinoma of the skin
- •Gastrointestinal dysfunction requiring parenteral nutrition
- •History of functional kidney transplant < 6 months prior to study entry
- •Anticipated live donor kidney transplant
- •Patients taking vitamin E supplements > 60 IU/day, vitamin C > 150 mg/day or other antioxidant or nutritional supplements
- •Incident hemodialysis patients (defined as within 30 days of dialysis initiation)
- •Patients hospitalized for more than 5 days within the past 30 days.
- •Patients with a history of a major atherosclerotic event (defined as combined incidence of myocardial infarction, urgent target-vessel revascularization, coronary bypass surgery, and stroke) within three months
- •Pregnancy
Outcomes
Primary Outcomes
Markers of endothelial function
Time Frame: 12 weeks
Endothelial function: Monocyte functional assays (cytokines)
Markers of oxidative stress
Time Frame: 12 weeks
Oxidative stress: F2-isoprostanes
Markers of inflammation
Time Frame: 12 weeks
Inflammation: C-reactive protein, Interleukin-6, and white blood cell count
Secondary Outcomes
- Number of subjects with adverse events and type of event(12 weeks)
Investigators
Jonathan Himmelfarb
Professor of Medicine
University of Washington