<clinical_study>
  <!-- This xml conforms to an XML Schema at:
    https://clinicaltrials.gov/ct2/html/images/info/public.xsd -->
  <required_header>
    <download_date>ClinicalTrials.gov processed this data on September 20, 2023</download_date>
    <link_text>Link to the current ClinicalTrials.gov record.</link_text>
    <url>https://clinicaltrials.gov/ct2/show/NCT01660516</url>
  </required_header>
  <id_info>
    <org_study_id>TEA-IRI</org_study_id>
    <secondary_id>Tea-IR-Injury-FMD</secondary_id>
    <nct_id>NCT01660516</nct_id>
  </id_info>
  <brief_title>Effect of Tea on Endothelial Function and Ischaemia-reperfusion Injury</brief_title>
  <official_title>Effect of Black Tea Consumption on Endothelial Function and Ischaemia-reperfusion Injury in Humans</official_title>
  <sponsors>
    <lead_sponsor>
      <agency>Radboud University Medical Center</agency>
      <agency_class>Other</agency_class>
    </lead_sponsor>
    <collaborator>
      <agency>Unilever R&amp;D</agency>
      <agency_class>Industry</agency_class>
    </collaborator>
  </sponsors>
  <source>Radboud University Medical Center</source>
  <oversight_info>
    <has_dmc>No</has_dmc>
  </oversight_info>
  <brief_summary>
    <textblock>
      Tea consumption may impact upon the decrease in endothelial function after IR-injury.&#xD;
      However, no previous study directly examined the potential of tea to impact upon the change&#xD;
      in endothelial function after IR-injury.&#xD;
&#xD;
      The investigators hypothesize that tea consumption counteracts endothelial damage in response&#xD;
      to ischaemia reperfusion injury in healthy humans.&#xD;
    </textblock>
  </brief_summary>
  <detailed_description>
    <textblock>
      Rationale: Occlusion of an artery (causing ischemia) is a frequently reported condition, e.g.&#xD;
      myocardial infarction, cerebral infarction or during organ transplantations. The period of&#xD;
      ischemia will be followed by reperfusion (possibly after an operation). The ischaemic period&#xD;
      as well as the reperfusion are both associated with damage to the tissue, including the&#xD;
      endothelium. It is hypothesised that production of oxidative stress and reduced NO&#xD;
      bioactivity (through increased reactive oxygen production) during ischaemia and reperfusion&#xD;
      is involved in the development of tissue damage to the endothelium. Interventions that can&#xD;
      prevent or attenuate endothelial dysfunction in response to ischemia-reperfusion (IR)-injury&#xD;
      have a potential clinical relevance to prevent (complications of) cardiovascular disease.&#xD;
&#xD;
      Several studies have examined the effect of tea consumption on the endothelial function.&#xD;
      These studies demonstrated a dose-dependent improvement of tea to improve endothelial&#xD;
      function in healthy and diseased humans, possibly through the vasoactive effects of&#xD;
      flavonoids, which may involve increased nitric oxide bioactivity and inhibition of NADPH&#xD;
      oxidase. Based on the ability of flavonoids to decrease (the impact of) oxidative stress, tea&#xD;
      consumption may also impact upon the decrease in endothelial function after IR-injury.&#xD;
      However, no previous study directly examined the potential of tea to impact upon the change&#xD;
      in endothelial function after IR-injury.&#xD;
&#xD;
      Objective: To examine whether tea consumption counteracts endothelial damage in response to&#xD;
      ischaemia reperfusion injury in healthy humans.&#xD;
&#xD;
      Main study parameters: Change in endothelial function (measured with flow mediated dilation)&#xD;
      after ischaemia reperfusion injury (induced by 20 minutes ischemia and 20 min reperfusion)&#xD;
      with and without precedence of tea consumption.&#xD;
&#xD;
      Nature and extent of the burden and risks associated with participation, benefit and group&#xD;
      relatedness: Non-invasive cuff occlusion is used to examine endothelial function (5-minute&#xD;
      ischaemia) and produce the stimulus that induces ischaemia-reperfusion injury (20-minute&#xD;
      ischaemia). This repeated cuff inflation is non-invasive and not associated with a health&#xD;
      risk for the subject. Tea consumption is safe and, most likely, daily routine for most&#xD;
      participants. The only difference is that this study will monitor and instruct participants&#xD;
      regarding their tea consumption in the week preceding the tests. The volunteers will not&#xD;
      benefit directly from participating in this study.&#xD;
    </textblock>
  </detailed_description>
  <overall_status>Completed</overall_status>
  <start_date>August 2011</start_date>
  <completion_date type="Actual">February 2012</completion_date>
  <primary_completion_date type="Actual">February 2012</primary_completion_date>
  <study_type>Observational</study_type>
  <has_expanded_access>No</has_expanded_access>
  <study_design_info>
    <observational_model>Case-Crossover</observational_model>
    <time_perspective>Cross-Sectional</time_perspective>
  </study_design_info>
  <primary_outcome>
    <measure>Change in Endothelial Function after ischaemia reperfusion injury</measure>
    <time_frame>three weeks</time_frame>
    <description>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</description>
  </primary_outcome>
  <secondary_outcome>
    <measure>Change in baseline flow mediated dilation after water/tea consumption</measure>
    <time_frame>three weeks</time_frame>
    <description>Change in baseline flow mediated dilation after water/tea consumption</description>
  </secondary_outcome>
  <number_of_groups>1</number_of_groups>
  <enrollment type="Actual">23</enrollment>
  <condition>Ischaemia Reperfusion Injury</condition>
  <arm_group>
    <arm_group_label>Tea</arm_group_label>
    <description>Black tea ingestion</description>
  </arm_group>
  <eligibility>
    <study_pop>
      <textblock>
        Twenty-one volunteers, aged between 30 and 70 years, were included in our study. All&#xD;
        subjects were healthy and free of (a history of) cardiovascular disease or obesity (BMI &gt;30&#xD;
        kg/m2). Individuals were excluded if they reported a chronic or acute disease, including&#xD;
        any kind of metabolic abnormality (such as diabetes mellitus) or cardiovascular disease.&#xD;
        Habitual smokers (n=3) were instructed to withdraw from smoking on the day of testing. To&#xD;
        further avoid confounding factors, the investigators also excluded individuals reporting&#xD;
        daily intense sporting activities (&gt;10 h/w), and/or were treated with a diet due to any&#xD;
        reason.&#xD;
      </textblock>
    </study_pop>
    <sampling_method>Probability Sample</sampling_method>
    <criteria>
      <textblock>
        Inclusion Criteria:&#xD;
&#xD;
          -  Healthy volunteers : age 18-60&#xD;
&#xD;
          -  All subjects: written informed consent&#xD;
&#xD;
        Exclusion Criteria:&#xD;
&#xD;
          -  Smoking&#xD;
&#xD;
          -  History of any cardiovascular disease&#xD;
&#xD;
          -  Hypertension (in supine position: systole &gt;140 mmHg, diastole &gt;90 mmHg)&#xD;
&#xD;
          -  Diabetes Mellitus&#xD;
&#xD;
          -  Hyperlipidaemia (fasting total cholesterol &gt;6.5 mmol/L)&#xD;
&#xD;
          -  Chronic use of medication known to interfere with the cardiovascular system&#xD;
&#xD;
          -  Professional athletes&#xD;
&#xD;
          -  Alcohol consumption &gt;14 units/week&#xD;
&#xD;
          -  BMI &gt;30 kg/m2&#xD;
      </textblock>
    </criteria>
    <gender>All</gender>
    <minimum_age>18 Years</minimum_age>
    <maximum_age>60 Years</maximum_age>
    <healthy_volunteers>Accepts Healthy Volunteers</healthy_volunteers>
  </eligibility>
  <overall_official>
    <last_name>Dick Thijssen, Dr.</last_name>
    <role>Principal Investigator</role>
    <affiliation>Radboud University Medical Centre Nijmegen</affiliation>
  </overall_official>
  <overall_official>
    <last_name>Maria Hopman, Prof. Dr.</last_name>
    <role>Principal Investigator</role>
    <affiliation>Radboud University Medical Center</affiliation>
  </overall_official>
  <location>
    <facility>
      <name>Radboud University Nijmegen Medical Centre</name>
      <address>
        <city>Nijmegen</city>
        <state>Gelderland</state>
        <zip>6525 EX</zip>
        <country>Netherlands</country>
      </address>
    </facility>
  </location>
  <location_countries>
    <country>Netherlands</country>
  </location_countries>
  <verification_date>July 2012</verification_date>
  <study_first_submitted>August 6, 2012</study_first_submitted>
  <study_first_submitted_qc>August 6, 2012</study_first_submitted_qc>
  <study_first_posted type="Estimate">August 8, 2012</study_first_posted>
  <last_update_submitted>February 1, 2013</last_update_submitted>
  <last_update_submitted_qc>February 1, 2013</last_update_submitted_qc>
  <last_update_posted type="Estimate">February 4, 2013</last_update_posted>
  <responsible_party>
    <responsible_party_type>Sponsor</responsible_party_type>
  </responsible_party>
  <keyword>Camellia sinensis</keyword>
  <keyword>flavonoids</keyword>
  <keyword>cardiovascular risk</keyword>
  <keyword>flow mediated dilation</keyword>
  <condition_browse>
    <!-- CAUTION:  The following MeSH terms are assigned with an imperfect algorithm            -->
    <mesh_term>Reperfusion Injury</mesh_term>
    <mesh_term>Ischemia</mesh_term>
    <mesh_term>Wounds and Injuries</mesh_term>
  </condition_browse>
  <!-- Results have not yet been posted for this study                                          -->
</clinical_study>


download date: ClinicalTrials.gov processed this data on September 20, 2023
link text: Link to the current ClinicalTrials.gov record.
url: https://clinicaltrials.gov/ct2/show/NCT01660516
org study id: TEA-IRI
secondary id: Tea-IR-Injury-FMD
nct id: NCT01660516
lead sponsor: 
collaborator: 
has dmc: No
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.
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.
observational model: Case-Crossover
time perspective: Cross-Sectional
measure: Change in Endothelial Function after ischaemia reperfusion injury
time frame: three weeks
description: 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
measure: Change in baseline flow mediated dilation after water/tea consumption
time frame: three weeks
description: Change in baseline flow mediated dilation after water/tea consumption
arm group label: Tea
description: Black tea ingestion
study pop: 
sampling method: Probability Sample
criteria: 
gender: All
minimum age: 18 Years
maximum age: 60 Years
healthy volunteers: Accepts Healthy Volunteers
last name: Dick Thijssen, Dr.
role: Principal Investigator
affiliation: Radboud University Medical Centre Nijmegen
last name: Maria Hopman, Prof. Dr.
role: Principal Investigator
affiliation: Radboud University Medical Center
facility: 
country: Netherlands
responsible party type: Sponsor
mesh term: Reperfusion Injury
mesh term: Ischemia
mesh term: Wounds and Injuries