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Effects of Onion Peel Extract on Endothelial Function

Effect of Onion Peel Extract on Endothelial Function and Endothelial Progenitor Cells in Overweight and Obese Subjects

Status
Completed
Phases
Phase 4
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT02180022
Enrollment
62
Registered
2014-07-02
Start date
2013-04-30
Completion date
2013-12-31
Last updated
2014-07-02

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Healthy, Obese, Overweight

Keywords

Quercetin, Endothelial function, Onion peel extract, volunteers

Brief summary

Acute or chronic intake of polyphenol-rich foods has been reported to improve endothelial function. Quercetin, found abundantly in onion, is a potent antioxidant flavonoid. This study was designed to investigate whether consumption of onion peel extract (OPE) improves endothelial function in healthy overweight and obese subjects.

Detailed description

Epidemiological studies have shown a rapid increase in the prevalence of overweight and obesity, not only in adults but also in children and adolescents, thus increasing the risk of early development of cardiovascular disease (CVD). Quercetin, found abundantly in onion, prevents the induction of endothelial dysfunction, superoxide production, and overexpression by angiotensin II in the rat aorta. Furthermore, in our previous study we showed that supplementation with quercetin-rich onion peel extract (OPE) influenced adipokine expression, thus addressing its modulatory effect on obesity-induced inflammation, and improved insulin resistance by alleviating the metabolic dysregulation of free fatty acids, suppressing oxidative stress, upregulating glucose uptake, and downregulating inflammatory gene expression. But there are limited studies on the relationship between quercetin supplementation and endothelial dysfunction in humans.

Interventions

DRUGPlacebo

After randomization, placebo was treated for 12 weeks

DRUGOnion peel extract

After randomization, onion peel extract was treated for 12 weeks

Sponsors

Kyunghee University
CollaboratorOTHER
Kyunghee University Medical Center
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
SUPPORTIVE_CARE
Masking
QUADRUPLE (Subject, Caregiver, Investigator, Outcomes Assessor)

Eligibility

Sex/Gender
ALL
Age
20 Years to 60 Years
Healthy volunteers
Yes

Inclusion criteria

* age 20 to 60 years * BMI \>23 kg/m2 * abdominal circumference \> 90 cm in males or \>85 cm in females

Exclusion criteria

* hypertension (\>140/90 mmHg), * diabetes * any cardiovascular disease, * kidney disease, * thyroid disease * cerebrovascular disease * liver disease (bilirubin level \>2 mg/dl) * pregnancy

Design outcomes

Primary

MeasureTime frameDescription
The difference of endothelial function12 weeks after study drug treatmentThe difference of forearm FMD (flow meidated dilation) achieved following study drug treatment

Secondary

MeasureTime frameDescription
The difference of EPC (endothelial progenitor cell) counts12 weeks after study drugs treatmentAfter appropriate gating based on low cytoplasmic granularity and low expression of CD45, CD34+VEGFR2+ cells were counted and expressed as the number of cells/106 total events or number of cells/100 µL of blood.

Other

MeasureTime frame
The composite measure of change of blood pressure, heart rate, body weight and blood chemistryup to 12 weeks

Countries

South Korea

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026