Ischaemia Reperfusion InjuryNCT01660516
Effect of Tea on Endothelial Function and Ischaemia-reperfusion Injury
An observational study of Ischaemia Reperfusion Injury, run by Radboud University Medical Center at 1 site in Netherlands.
Trial summary
Tea consumption may impact upon the decrease in endothelial function after IR-injury. However, no previous study directly examined the potential of tea to impact upon the change in endothelial function after IR-injury. Read more about this study
- Who is it for?
- Ages 18 to 60 yearsHealthy volunteers can take part
- Conditions the study is for
- Ischaemia Reperfusion Injury
- How many people
- 23 participants
- Where
- 1 siteNetherlands
- Study dates
- Aug 2011to Feb 2012
- Phase
- Observational
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 60 years
- All sexes
- Healthy volunteers accepted
- Adult
Study population: Twenty-one volunteers, aged between 30 and 70 years, were included in our study. All subjects were healthy and free of (a history of) cardiovascular disease or obesity (BMI >30 kg/m2). Individuals were excluded if they reported a chronic or acute disease, including any kind of metabolic abnormality (such as diabetes mellitus) or cardiovascular disease. Habitual smokers (n=3) were instructed to withdraw from smoking on the day of testing. To further avoid confounding factors, the investigators also excluded individuals reporting daily intense sporting activities (>10 h/w), and/or were treated with a diet due to any reason.
Who may be able to join
- Healthy volunteers : age 18-60
- All subjects: written informed consent
Who cannot join
- Smoking
- History of any cardiovascular disease
- Hypertension (in supine position: systole >140 mmHg, diastole >90 mmHg)
- Diabetes Mellitus
- Hyperlipidaemia (fasting total cholesterol >6.5 mmol/L)
- Chronic use of medication known to interfere with the cardiovascular system
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- Professional athletes
- Alcohol consumption >14 units/week
- BMI >30 kg/m2
Trial locations and contacts
1 site in 1 country.
Netherlands1 site
Radboud University Nijmegen Medical Centre
Nijmegen, Gelderland, 6525 EX
About this study
Official title: Effect of Black Tea Consumption on Endothelial Function and Ischaemia-reperfusion Injury in Humans
Tea consumption may impact upon the decrease in endothelial function after IR-injury. However, no previous study directly examined the potential of tea to impact upon the change in endothelial function after IR-injury.
The investigators hypothesize that tea consumption counteracts endothelial damage in response to ischaemia reperfusion injury in healthy humans.
Read the detailed description
Rationale: Occlusion of an artery (causing ischemia) is a frequently reported condition, e.g. myocardial infarction, cerebral infarction or during organ transplantations. The period of ischemia will be followed by reperfusion (possibly after an operation). The ischaemic period as well as the reperfusion are both associated with damage to the tissue, including the endothelium. It is hypothesised that production of oxidative stress and reduced NO bioactivity (through increased reactive oxygen production) during ischaemia and reperfusion is involved in the development of tissue damage to the endothelium. Interventions that can prevent or attenuate endothelial dysfunction in response to ischemia-reperfusion (IR)-injury have a potential clinical relevance to prevent (complications of) cardiovascular disease.
Several studies have examined the effect of tea consumption on the endothelial function. These studies demonstrated a dose-dependent improvement of tea to improve endothelial function in healthy and diseased humans, possibly through the vasoactive effects of flavonoids, which may involve increased nitric oxide bioactivity and inhibition of NADPH oxidase. Based on the ability of flavonoids to decrease (the impact of) oxidative stress, tea consumption may also impact upon the decrease in endothelial function after IR-injury. However, no previous study directly examined the potential of tea to impact upon the change in endothelial function after IR-injury.
Objective: To examine whether tea consumption counteracts endothelial damage in response to ischaemia reperfusion injury in healthy humans.
Main study parameters: Change in endothelial function (measured with flow mediated dilation) after ischaemia reperfusion injury (induced by 20 minutes ischemia and 20 min reperfusion) with and without precedence of tea consumption.
Nature and extent of the burden and risks associated with participation, benefit and group relatedness: Non-invasive cuff occlusion is used to examine endothelial function (5-minute ischaemia) and produce the stimulus that induces ischaemia-reperfusion injury (20-minute ischaemia). This repeated cuff inflation is non-invasive and not associated with a health risk for the subject. Tea consumption is safe and, most likely, daily routine for most participants. The only difference is that this study will monitor and instruct participants regarding their tea consumption in the week preceding the tests. The volunteers will not benefit directly from participating in this study.
- Conditions
- Ischaemia Reperfusion Injury
- Keywords
- Camellia sinensis, flavonoids, cardiovascular risk, flow mediated dilation
- Medical subject headings
- Reperfusion Injury
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
| Study group | Role | What they receive |
|---|---|---|
| Tea | Black tea ingestion |
What is being measured
The primary outcome is the main question the study is designed to answer.
Change in Endothelial Function after ischaemia reperfusion injury
Change in endothelial function (measured with flow mediated dilation) after ischaemia reperfusion injury (induced by 20 minutes ischemia and 20 min reperfusion) with and without precedence of tea consumption
Measured: three weeks
Secondary outcomes (1)
Change in baseline flow mediated dilation after water/tea consumption
Change in baseline flow mediated dilation after water/tea consumption
Measured: three weeks
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted8 Aug 2012 (estimated)
- Study startAug 2011
- Primary completionFeb 2012
- Study completionFeb 2012
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Ischaemia Reperfusion InjuryStudies of the same condition, open and under way.
- More trials run by Radboud University Medical CenterThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Case crossover
- Time perspective
- Cross-sectional
- Enrolment
- 23 participants (actual)
Sponsor and investigators
- Lead sponsor
- Radboud University Medical Center
- Sponsor type
- University, hospital or other
- Collaborators
- Unilever R&D
- Responsible party
- Sponsor
- Investigators
- Dick Thijssen, Dr., Principal investigator, Radboud University Medical Centre NijmegenMaria Hopman, Prof. Dr., Principal investigator, Radboud University Medical Center
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT01660516
- Sponsor's protocol ID
- TEA-IRI
- Other IDs
- Tea-IR-Injury-FMD
- Status last verified
- Jul 2012
- First submitted
- 6 Aug 2012
- Last updated
- 4 Feb 2013
- Results posted
- No
- Data monitoring committee
- No
Study at a glance
From the registry record, last updated by the sponsor on 4 Feb 2013. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Effect of Black Tea Consumption on Endothelial Function and Ischaemia-reperfusion Injury in Humans
- ClinicalTrials.gov ID
- NCT01660516
- Acronym / sponsor ID
- TEA-IRI
- Conditions
- Ischaemia Reperfusion Injury
- Keywords
- Camellia sinensis, flavonoids, cardiovascular risk, flow mediated dilation
- Study type
- Observational
- Recruitment status
- Completed
- Enrolment
- 23 participants (actual)
- Lead sponsor
- Radboud University Medical CenterUniversity, hospital or other
- Collaborators
- Unilever R&D
- Study start
- Aug 2011
- Primary completion
- Feb 2012 (actual)
- Study completion
- Feb 2012 (actual)
- First posted
- 8 Aug 2012 (estimated)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Tea consumption may impact upon the decrease in endothelial function after IR-injury. However, no previous study directly examined the potential of tea to impact upon the change in endothelial function after IR-injury.
The investigators hypothesize that tea consumption counteracts endothelial damage in response to ischaemia reperfusion injury in healthy humans.
Detailed description
Rationale: Occlusion of an artery (causing ischemia) is a frequently reported condition, e.g. myocardial infarction, cerebral infarction or during organ transplantations. The period of ischemia will be followed by reperfusion (possibly after an operation). The ischaemic period as well as the reperfusion are both associated with damage to the tissue, including the endothelium. It is hypothesised that production of oxidative stress and reduced NO bioactivity (through increased reactive oxygen production) during ischaemia and reperfusion is involved in the development of tissue damage to the endothelium. Interventions that can prevent or attenuate endothelial dysfunction in response to ischemia-reperfusion (IR)-injury have a potential clinical relevance to prevent (complications of) cardiovascular disease.
Several studies have examined the effect of tea consumption on the endothelial function. These studies demonstrated a dose-dependent improvement of tea to improve endothelial function in healthy and diseased humans, possibly through the vasoactive effects of flavonoids, which may involve increased nitric oxide bioactivity and inhibition of NADPH oxidase. Based on the ability of flavonoids to decrease (the impact of) oxidative stress, tea consumption may also impact upon the decrease in endothelial function after IR-injury. However, no previous study directly examined the potential of tea to impact upon the change in endothelial function after IR-injury.
Objective: To examine whether tea consumption counteracts endothelial damage in response to ischaemia reperfusion injury in healthy humans.
Main study parameters: Change in endothelial function (measured with flow mediated dilation) after ischaemia reperfusion injury (induced by 20 minutes ischemia and 20 min reperfusion) with and without precedence of tea consumption.
Nature and extent of the burden and risks associated with participation, benefit and group relatedness: Non-invasive cuff occlusion is used to examine endothelial function (5-minute ischaemia) and produce the stimulus that induces ischaemia-reperfusion injury (20-minute ischaemia). This repeated cuff inflation is non-invasive and not associated with a health risk for the subject. Tea consumption is safe and, most likely, daily routine for most participants. The only difference is that this study will monitor and instruct participants regarding their tea consumption in the week preceding the tests. The volunteers will not benefit directly from participating in this study.
Study design
- Observational model
- Case crossover
- Time perspective
- Cross-sectional
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Tea | – | –Black tea ingestion |
Who may qualify
- Ages
- 18 to 60 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult
- Study population
- Twenty-one volunteers, aged between 30 and 70 years, were included in our study. All subjects were healthy and free of (a history of) cardiovascular disease or obesity (BMI >30 kg/m2). Individuals were excluded if they reported a chronic or acute disease, including any kind of metabolic abnormality (such as diabetes mellitus) or cardiovascular disease. Habitual smokers (n=3) were instructed to withdraw from smoking on the day of testing. To further avoid confounding factors, the investigators also excluded individuals reporting daily intense sporting activities (>10 h/w), and/or were treated with a diet due to any reason.
Key inclusion criteria (2 listed)
- Healthy volunteers : age 18-60
- All subjects: written informed consent
Key exclusion criteria (9 listed)
- Smoking
- History of any cardiovascular disease
- Hypertension (in supine position: systole >140 mmHg, diastole >90 mmHg)
- Diabetes Mellitus
- Hyperlipidaemia (fasting total cholesterol >6.5 mmol/L)
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Primary outcome
Change in Endothelial Function after ischaemia reperfusion injury
Time frame: three weeks
Change in endothelial function (measured with flow mediated dilation) after ischaemia reperfusion injury (induced by 20 minutes ischemia and 20 min reperfusion) with and without precedence of tea consumption
1 secondary outcome
Change in baseline flow mediated dilation after water/tea consumption
Time frame: three weeks
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 4 Feb 2013.
Related trials for Ischaemia Reperfusion Injury
Not yet recruiting
Effect of Discarding Initial Reperfusion Blood on Hemodynamics, Liver Function, and 30-Day Outcomes in Liver Transplantation
Liver Transplantation, Ischaemia Reperfusion Injury
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Dick Thijssen, Dr. principal investigator
Radboud University Medical Centre Nijmegen
Maria Hopman, Prof. Dr. principal investigator
Radboud University Medical Center
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Ischaemia Reperfusion Injury, run by Radboud University Medical Center at 1 site in Netherlands.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 2 inclusion and 9 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 4 Feb 2013. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Netherlands. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Change in Endothelial Function after ischaemia reperfusion injury (time frame: three weeks). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 4 Feb 2013; AzTrials last refreshed its copy on 7 Nov 2026.