<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/NCT03784742</url>
  </required_header>
  <id_info>
    <org_study_id>347890</org_study_id>
    <nct_id>NCT03784742</nct_id>
  </id_info>
  <brief_title>Effects of Daily Nitrate Consumption on Oral Bacteria Composition, Blood Pressure and Vascular Function</brief_title>
  <acronym>REBOC2</acronym>
  <official_title>Investigation of the Effects of Daily Nitrate Consumption on Oral Bacteria Composition, Blood Pressure and Vascular Functio</official_title>
  <sponsors>
    <lead_sponsor>
      <agency>University of Reading</agency>
      <agency_class>Other</agency_class>
    </lead_sponsor>
    <collaborator>
      <agency>Saudi Cultural Bureau</agency>
      <agency_class>Other</agency_class>
    </collaborator>
  </sponsors>
  <source>University of Reading</source>
  <oversight_info>
    <has_dmc>No</has_dmc>
    <is_fda_regulated_drug>No</is_fda_regulated_drug>
    <is_fda_regulated_device>No</is_fda_regulated_device>
  </oversight_info>
  <brief_summary>
    <textblock>
      Diseases of the heart and blood vessels, including raised blood pressure, are one of the&#xD;
      leading causes of death worldwide. Higher intakes of dietary nitrate, found abundantly in&#xD;
      root vegetables such as beetroot, have been shown to have health benefits including lowering&#xD;
      blood pressure and improving the elasticity of blood vessels. Bacteria which reside in the&#xD;
      mouth and those in the gastrointestinal tract play an important role in converting dietary&#xD;
      nitrate to nitrite and nitric oxide (a chemical which promotes the relaxation of blood&#xD;
      vessels). In particular, removal of oral bacteria by using antiseptic mouthwash is&#xD;
      accompanied by an increase in blood pressure in subjects with normal blood pressure, even&#xD;
      after consuming nitrate-rich foods. To date, very little is known about the role of these&#xD;
      oral bacteria in the control of blood pressure, and if there are any differences in bacterial&#xD;
      composition between individuals.&#xD;
    </textblock>
  </brief_summary>
  <detailed_description>
    <textblock>
      Interested volunteers will be provided with an outline of the study and asked to complete a&#xD;
      medical and lifestyle questionnaire (in person, by email or over the phone). Potentially&#xD;
      suitable participants will be identified and asked to attend a screening session after a 12 h&#xD;
      overnight fast (not eating during this time and only drinking water) during which the study&#xD;
      will be explained in more detail before a consent form is signed. Anthropometric measurements&#xD;
      will then be taken including weight, height and blood pressure. A 9 ml blood sample will also&#xD;
      be collected on site at the Department of Food and Nutritional Sciences (Hugh Sinclair Unit&#xD;
      of Human Nutrition). Subjects who meet the initial inclusion criteria will be invited to a&#xD;
      further screening session during which time a dentist will check for dental diseases (e.g.&#xD;
      current dental cavities or periodontal infection) and saliva flow rate. Volunteers without&#xD;
      periodontal disease and with normal saliva flow will then be invited to participate in the&#xD;
      study.&#xD;
&#xD;
      Eligible subjects will then be randomised to one of two treatments: i) up to 70 ml (the&#xD;
      amount given will be equivalent to 3.7 mg/kg body weight) beetroot juice (James White Drinks&#xD;
      Limited, UK) or ii) a matched volume of placebo beetroot juice (control, James White Drinks&#xD;
      Limited, UK) to be consumed daily for 8 weeks. As drinking water is a major source of dietary&#xD;
      nitrate, subjects will be provided with a water filter to reduce the nitrate level in their&#xD;
      tap water for drinking and cooking during the study period. There will be a wash out period&#xD;
      of 4 weeks between the intervention juices. In total, volunteers will be involved in the&#xD;
      study for 20 weeks (five months).&#xD;
&#xD;
      On the day before each baseline study visit (weeks 0 and 12), volunteers will be required to&#xD;
      fast overnight after having a low nitrate evening meal and only drinking low nitrate mineral&#xD;
      water (Buxton mineral water), which will be provided to them, during this time. They will&#xD;
      refrain from strenuous exercise and alcohol. On the morning of the study visit, the&#xD;
      volunteers will be asked not to brush their teeth before they come to the clinical unit for&#xD;
      their study visit.&#xD;
&#xD;
      When they arrive in the fasted state, the participants will be asked to provide a spot urine&#xD;
      sample and a stool sample. Body weight and composition will be measured using the Tanita&#xD;
      weighing scale, saliva sample and an oral bacteria sample will be collected by swabbing the&#xD;
      tongue with a cotton swab. Volunteers will be asked to lie down for 20 minutes prior to the&#xD;
      measurement of blood pressure and pulse wave analysis (PWA) using the Mobil-O-Graph device&#xD;
      followed by the assessment of microvascular reactivity using Laser Doppler Imaging with&#xD;
      iontophoresis. A blood sample of 20 ml (equivalent to just over 1 tablespoon) will then be&#xD;
      taken before a light breakfast is provided. Volunteers will then be given a toothbrush and&#xD;
      toothpaste to brush their teeth and asked to complete an online food frequency questionnaire&#xD;
      (EatwellUK).&#xD;
&#xD;
      During the four-week wash-out period between interventions, participants will be instructed&#xD;
      to avoid any beetroot juice drinks and maintain their usual dietary and lifestyle habits.&#xD;
    </textblock>
  </detailed_description>
  <overall_status>Unknown status</overall_status>
  <last_known_status>Not yet recruiting</last_known_status>
  <start_date type="Anticipated">December 2018</start_date>
  <completion_date type="Anticipated">December 2019</completion_date>
  <primary_completion_date type="Anticipated">August 2019</primary_completion_date>
  <phase>N/A</phase>
  <study_type>Interventional</study_type>
  <has_expanded_access>No</has_expanded_access>
  <study_design_info>
    <allocation>Randomized</allocation>
    <intervention_model>Crossover Assignment</intervention_model>
    <primary_purpose>Treatment</primary_purpose>
    <masking>Double (Participant, Investigator)</masking>
  </study_design_info>
  <primary_outcome>
    <measure>Change in blood pressure measure</measure>
    <time_frame>Before and after each 8 week intervention</time_frame>
    <description>Systolic blood pressure, diastolic blood pressure and pulse pressure</description>
  </primary_outcome>
  <primary_outcome>
    <measure>Change in oral bacteria composition</measure>
    <time_frame>Before and after each 8 week intervention</time_frame>
    <description>Oral bacteria composition determined using next generation sequencing.</description>
  </primary_outcome>
  <secondary_outcome>
    <measure>Change in vascular reactivity</measure>
    <time_frame>Before and after each 8 week intervention</time_frame>
    <description>Laser Doppler Imaging with iontophoresis.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Change in Nox concentrations in serum, urine and saliva</measure>
    <time_frame>Before and after each 8 week intervention</time_frame>
    <description>Nitrate and nitrite concentrations will be determined using high performance liquid chromatography in plasma, urine and saliva. Nitric oxide will be calculated as the sum of nitrate and nitrite concentrations.&#xD;
Creatinine will be measured in the urine samples to normalise the nitrate and nitrite concentrations in urine for hydration status.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Change in gut bacteria composition</measure>
    <time_frame>Before and after each 8 week intervention</time_frame>
    <description>Stool sample will be analysed to determine composition using next generation sequencing will be used to find the differences between treatments.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Change in fasting lipid profile</measure>
    <time_frame>Before and after each 8 week intervention</time_frame>
    <description>Total cholesterol, HDL-C, and triacylglycerol will be measured using a clinical chemistry analyser. LDL-C will be calculated using the Friedewald formula.</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Change in C-reactive protein</measure>
    <time_frame>Before and after each 8 week intervention</time_frame>
    <description>C-reactive protein will be measured using a clinical chemistry analyser</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Change in endothelial function</measure>
    <time_frame>Before and after each 8 week intervention</time_frame>
    <description>Pulse wave analysis will be measured using Mobil-O-Graph</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Change in body weight</measure>
    <time_frame>Before and after each 8 week intervention</time_frame>
    <description>Body weight will be measured using a Tanita scale</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Height measurement</measure>
    <time_frame>Before the intervention</time_frame>
    <description>Height will be measured using a stadiometer</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Change in body mass index</measure>
    <time_frame>Before and after each 8 week intervention</time_frame>
    <description>Body mass index will be calculated from the body weight and height measurement</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Change in insulin</measure>
    <time_frame>Before and after each 8 week intervention</time_frame>
    <description>Insulin levels will be measured by ELISA</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Change in glucose</measure>
    <time_frame>Before and after each 8 week intervention</time_frame>
    <description>Glucose levels will be measured using a clinical chemistry analyser</description>
  </secondary_outcome>
  <secondary_outcome>
    <measure>Change in insulin sensitivity</measure>
    <time_frame>Before and after each 8 week intervention</time_frame>
    <description>Glucose and insulin measurements will be used to calculate the homeostatic model assessment of insulin resistance (HOMA-IR)</description>
  </secondary_outcome>
  <number_of_arms>2</number_of_arms>
  <enrollment type="Anticipated">28</enrollment>
  <condition>No Dental Disease</condition>
  <condition>Non-smoking</condition>
  <arm_group>
    <arm_group_label>Nitrate-rich Beetroot juice</arm_group_label>
    <arm_group_type>Active Comparator</arm_group_type>
    <description>Nitrate-rich beetroot juice equivalent to 3.7 mg nitrate per kg body weight daily for 8 weeks.</description>
  </arm_group>
  <arm_group>
    <arm_group_label>Placebo beetroot juice</arm_group_label>
    <arm_group_type>Placebo Comparator</arm_group_type>
    <description>Placebo beetroot juice (equivalent volume to the amount of nitrate-rich beetroot juice consumed) daily for 8 weeks.</description>
  </arm_group>
  <intervention>
    <intervention_type>Other</intervention_type>
    <intervention_name>Nitrate rich beetroot juice</intervention_name>
    <description>James White Drinks Limited beetroot juice (0.4-0.45 g nitrate/70 ml drink).</description>
    <arm_group_label>Nitrate-rich Beetroot juice</arm_group_label>
  </intervention>
  <intervention>
    <intervention_type>Other</intervention_type>
    <intervention_name>Placebo beetroot juice</intervention_name>
    <description>James White Drinks Limited Placebo beetroot juice (0 nitrate/70 ml drink).</description>
    <arm_group_label>Placebo beetroot juice</arm_group_label>
  </intervention>
  <eligibility>
    <criteria>
      <textblock>
        Inclusion Criteria:&#xD;
&#xD;
        Male and female;&#xD;
&#xD;
          -  A signed consent form;&#xD;
&#xD;
          -  Blood pressure &lt;140/90 mm Hg;&#xD;
&#xD;
          -  BMI range 18.5 - 39.9 kg/m2;&#xD;
&#xD;
          -  Age 18-64 years;&#xD;
&#xD;
          -  Non-smoking;&#xD;
&#xD;
          -  Not taking blood pressure lowering medication or using medications known to influence&#xD;
             vascular function such as a glyceryl trinitrate (GTN) spray;&#xD;
&#xD;
          -  No recent (within 3 months) or current use of antibiotics.&#xD;
&#xD;
        Exclusion criteria are:&#xD;
&#xD;
        Diagnosed with a chronic illness;&#xD;
&#xD;
          -  Anaemia defined as a haemoglobin &lt; 115 g/l for women and &lt;130 g/l for men;&#xD;
&#xD;
          -  Individuals with food allergies or allergies to medicated mouthwash or ingredients in&#xD;
             the oral products;&#xD;
&#xD;
          -  Requirements to take long-term medication active on the oral cavity including&#xD;
             prebiotics and probiotics or have taken antibiotics within the last 3 months;&#xD;
&#xD;
          -  Gingivitis diagnosis, or periodontal disease or chronic oral complaints or existing&#xD;
             oral pathology.&#xD;
&#xD;
          -  Less than four natural (enamel) buccal surfaces of upper molars available;&#xD;
&#xD;
          -  Presence of fixed or removable oral appliances (e.g., dentures, orthodontic wires);&#xD;
             xerostomia (a persistent dry mouth) diagnosis;&#xD;
&#xD;
          -  Current smoker;&#xD;
&#xD;
          -  Already participating in a dietary intervention study or clinical trial;&#xD;
&#xD;
          -  Excessive alcohol consumption (&gt; 14 units/wk);&#xD;
&#xD;
          -  Females who are pregnant or lactating;&#xD;
&#xD;
          -  Individuals not willing to give up using mouthwash or change their dental hygiene&#xD;
             routine. Regular consumption or use of xylitol-based products such as toothpaste and&#xD;
             chewing gum.&#xD;
      </textblock>
    </criteria>
    <gender>All</gender>
    <minimum_age>18 Years</minimum_age>
    <maximum_age>64 Years</maximum_age>
    <healthy_volunteers>Accepts Healthy Volunteers</healthy_volunteers>
  </eligibility>
  <overall_official>
    <last_name>Julie A Lovegrove, BSc, PhD</last_name>
    <role>Principal Investigator</role>
    <affiliation>University of Reading</affiliation>
  </overall_official>
  <overall_contact>
    <last_name>Julie A Lovegrove, BSc, PhD</last_name>
    <phone>0044118378</phone>
    <phone_ext>6418</phone_ext>
    <email>j.a.ovegrove@reading.ac.uk</email>
  </overall_contact>
  <overall_contact_backup>
    <last_name>Hayat S Alzahrani, MSc</last_name>
    <phone>07496966022</phone>
    <email>h.s.alzahrani@pgr.reading.ac.uk</email>
  </overall_contact_backup>
  <location>
    <facility>
      <name>Hugh Sinclair Unit of Human Nutrition, Department of Food and Nutritional Sciences, University of Reading</name>
      <address>
        <city>Reading</city>
        <state>Berkshire</state>
        <zip>RG6 6AP</zip>
        <country>United Kingdom</country>
      </address>
    </facility>
    <contact>
      <last_name>Julie Lovegrove, Professor</last_name>
      <phone>0044(0)1183786418</phone>
      <email>j.a.lovegrove@reading.ac.uk</email>
    </contact>
    <contact_backup>
      <last_name>Kim Jackson, PhD</last_name>
      <phone>0118378</phone>
      <phone_ext>5361</phone_ext>
      <email>k.g.jackson@reading.ac.uk</email>
    </contact_backup>
  </location>
  <location_countries>
    <country>United Kingdom</country>
  </location_countries>
  <verification_date>December 2018</verification_date>
  <study_first_submitted>November 1, 2018</study_first_submitted>
  <study_first_submitted_qc>December 20, 2018</study_first_submitted_qc>
  <study_first_posted type="Actual">December 24, 2018</study_first_posted>
  <last_update_submitted>December 20, 2018</last_update_submitted>
  <last_update_submitted_qc>December 20, 2018</last_update_submitted_qc>
  <last_update_posted type="Actual">December 24, 2018</last_update_posted>
  <responsible_party>
    <responsible_party_type>Principal Investigator</responsible_party_type>
    <investigator_affiliation>University of Reading</investigator_affiliation>
    <investigator_full_name>Julie Lovegrove</investigator_full_name>
    <investigator_title>Professor of Human Nutrition, Head of the Hugh Sinclair Unit of Human Nutrition</investigator_title>
  </responsible_party>
  <condition_browse>
    <!-- CAUTION:  The following MeSH terms are assigned with an imperfect algorithm            -->
    <mesh_term>Stomatognathic Diseases</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/NCT03784742
org study id: 347890
nct id: NCT03784742
lead sponsor: 
collaborator: 
has dmc: No
is fda regulated drug: No
is fda regulated device: No
Diseases of the heart and blood vessels, including raised blood pressure, are one of the
      leading causes of death worldwide. Higher intakes of dietary nitrate, found abundantly in
      root vegetables such as beetroot, have been shown to have health benefits including lowering
      blood pressure and improving the elasticity of blood vessels. Bacteria which reside in the
      mouth and those in the gastrointestinal tract play an important role in converting dietary
      nitrate to nitrite and nitric oxide (a chemical which promotes the relaxation of blood
      vessels). In particular, removal of oral bacteria by using antiseptic mouthwash is
      accompanied by an increase in blood pressure in subjects with normal blood pressure, even
      after consuming nitrate-rich foods. To date, very little is known about the role of these
      oral bacteria in the control of blood pressure, and if there are any differences in bacterial
      composition between individuals.
Interested volunteers will be provided with an outline of the study and asked to complete a
      medical and lifestyle questionnaire (in person, by email or over the phone). Potentially
      suitable participants will be identified and asked to attend a screening session after a 12 h
      overnight fast (not eating during this time and only drinking water) during which the study
      will be explained in more detail before a consent form is signed. Anthropometric measurements
      will then be taken including weight, height and blood pressure. A 9 ml blood sample will also
      be collected on site at the Department of Food and Nutritional Sciences (Hugh Sinclair Unit
      of Human Nutrition). Subjects who meet the initial inclusion criteria will be invited to a
      further screening session during which time a dentist will check for dental diseases (e.g.
      current dental cavities or periodontal infection) and saliva flow rate. Volunteers without
      periodontal disease and with normal saliva flow will then be invited to participate in the
      study.

      Eligible subjects will then be randomised to one of two treatments: i) up to 70 ml (the
      amount given will be equivalent to 3.7 mg/kg body weight) beetroot juice (James White Drinks
      Limited, UK) or ii) a matched volume of placebo beetroot juice (control, James White Drinks
      Limited, UK) to be consumed daily for 8 weeks. As drinking water is a major source of dietary
      nitrate, subjects will be provided with a water filter to reduce the nitrate level in their
      tap water for drinking and cooking during the study period. There will be a wash out period
      of 4 weeks between the intervention juices. In total, volunteers will be involved in the
      study for 20 weeks (five months).

      On the day before each baseline study visit (weeks 0 and 12), volunteers will be required to
      fast overnight after having a low nitrate evening meal and only drinking low nitrate mineral
      water (Buxton mineral water), which will be provided to them, during this time. They will
      refrain from strenuous exercise and alcohol. On the morning of the study visit, the
      volunteers will be asked not to brush their teeth before they come to the clinical unit for
      their study visit.

      When they arrive in the fasted state, the participants will be asked to provide a spot urine
      sample and a stool sample. Body weight and composition will be measured using the Tanita
      weighing scale, saliva sample and an oral bacteria sample will be collected by swabbing the
      tongue with a cotton swab. Volunteers will be asked to lie down for 20 minutes prior to the
      measurement of blood pressure and pulse wave analysis (PWA) using the Mobil-O-Graph device
      followed by the assessment of microvascular reactivity using Laser Doppler Imaging with
      iontophoresis. A blood sample of 20 ml (equivalent to just over 1 tablespoon) will then be
      taken before a light breakfast is provided. Volunteers will then be given a toothbrush and
      toothpaste to brush their teeth and asked to complete an online food frequency questionnaire
      (EatwellUK).

      During the four-week wash-out period between interventions, participants will be instructed
      to avoid any beetroot juice drinks and maintain their usual dietary and lifestyle habits.
allocation: Randomized
intervention model: Crossover Assignment
primary purpose: Treatment
masking: Double (Participant, Investigator)
measure: Change in blood pressure measure
time frame: Before and after each 8 week intervention
description: Systolic blood pressure, diastolic blood pressure and pulse pressure
measure: Change in oral bacteria composition
time frame: Before and after each 8 week intervention
description: Oral bacteria composition determined using next generation sequencing.
measure: Change in vascular reactivity
time frame: Before and after each 8 week intervention
description: Laser Doppler Imaging with iontophoresis.
measure: Change in Nox concentrations in serum, urine and saliva
time frame: Before and after each 8 week intervention
description: Nitrate and nitrite concentrations will be determined using high performance liquid chromatography in plasma, urine and saliva. Nitric oxide will be calculated as the sum of nitrate and nitrite concentrations.
Creatinine will be measured in the urine samples to normalise the nitrate and nitrite concentrations in urine for hydration status.
measure: Change in gut bacteria composition
time frame: Before and after each 8 week intervention
description: Stool sample will be analysed to determine composition using next generation sequencing will be used to find the differences between treatments.
measure: Change in fasting lipid profile
time frame: Before and after each 8 week intervention
description: Total cholesterol, HDL-C, and triacylglycerol will be measured using a clinical chemistry analyser. LDL-C will be calculated using the Friedewald formula.
measure: Change in C-reactive protein
time frame: Before and after each 8 week intervention
description: C-reactive protein will be measured using a clinical chemistry analyser
measure: Change in endothelial function
time frame: Before and after each 8 week intervention
description: Pulse wave analysis will be measured using Mobil-O-Graph
measure: Change in body weight
time frame: Before and after each 8 week intervention
description: Body weight will be measured using a Tanita scale
measure: Height measurement
time frame: Before the intervention
description: Height will be measured using a stadiometer
measure: Change in body mass index
time frame: Before and after each 8 week intervention
description: Body mass index will be calculated from the body weight and height measurement
measure: Change in insulin
time frame: Before and after each 8 week intervention
description: Insulin levels will be measured by ELISA
measure: Change in glucose
time frame: Before and after each 8 week intervention
description: Glucose levels will be measured using a clinical chemistry analyser
measure: Change in insulin sensitivity
time frame: Before and after each 8 week intervention
description: Glucose and insulin measurements will be used to calculate the homeostatic model assessment of insulin resistance (HOMA-IR)
arm group label: Nitrate-rich Beetroot juice
arm group type: Active Comparator
description: Nitrate-rich beetroot juice equivalent to 3.7 mg nitrate per kg body weight daily for 8 weeks.
arm group label: Placebo beetroot juice
arm group type: Placebo Comparator
description: Placebo beetroot juice (equivalent volume to the amount of nitrate-rich beetroot juice consumed) daily for 8 weeks.
intervention type: Other
intervention name: Nitrate rich beetroot juice
description: James White Drinks Limited beetroot juice (0.4-0.45 g nitrate/70 ml drink).
arm group label: Nitrate-rich Beetroot juice
intervention type: Other
intervention name: Placebo beetroot juice
description: James White Drinks Limited Placebo beetroot juice (0 nitrate/70 ml drink).
arm group label: Placebo beetroot juice
criteria: 
gender: All
minimum age: 18 Years
maximum age: 64 Years
healthy volunteers: Accepts Healthy Volunteers
last name: Julie A Lovegrove, BSc, PhD
role: Principal Investigator
affiliation: University of Reading
last name: Julie A Lovegrove, BSc, PhD
phone: 0044118378
phone ext: 6418
email: j.a.ovegrove@reading.ac.uk
last name: Hayat S Alzahrani, MSc
phone: 07496966022
email: h.s.alzahrani@pgr.reading.ac.uk
facility: 
contact: 
contact backup: 
country: United Kingdom
responsible party type: Principal Investigator
investigator affiliation: University of Reading
investigator full name: Julie Lovegrove
investigator title: Professor of Human Nutrition, Head of the Hugh Sinclair Unit of Human Nutrition
mesh term: Stomatognathic Diseases