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Planetary Habitat Simulation: Nutrition Studies (PlanHab)

Primary Purpose

Hypoxia

Status
Completed
Phase
Not Applicable
Locations
Study Type
Interventional
Intervention
Hypoxic ambulatory
Hypoxic Bedrest
Normoxic Bedrest
Sponsored by
University of Nottingham
About
Eligibility
Locations
Arms
Outcomes
Full info

About this trial

This is an interventional basic science trial for Hypoxia focused on measuring Bedrest, Appetite

Eligibility Criteria

25 Years - 45 Years (Adult)MaleAccepts Healthy Volunteers

Inclusion Criteria:

  • Physically and mentally healthy subjects
  • Body mass index < 25 kg/m2
  • Height 158 - 190 cm
  • Waist circumference < 94 cm
  • Volunteers that are able to declare their willingness to participate in the entire study
  • Willing to be assigned randomly to the three groups
  • Successfully passing the psychological and medical screening
  • competent to sign informed consent
  • Slovenian social insurance
  • English language fluency

Exclusion Criteria:

  • Medication required that may interfere with the interpretation of the results
  • Bone mineral density (as measured by DEXA) more than 1.5 standard deviations < t score
  • Recent sub-standard nutritional status
  • Family history of thrombosis or positive response in thrombosis screening procedure.

(Biochemical analysis of the following parameters: ATIII, High sensitive C-reactive protein, S-Akt., Factor V-Leiden, Prothrombin, Lupus-partial thromboplastin time, Factor II)

  • History of: thyroid dysfunction, renal stones, diabetes, allergies, hypertension, hypocalcemia, uric acidaemia, lipidaemia, or hyperhomocysteinaemia
  • Gastro-esophageal reflux disease or renal function disorder, Hiatus hernia
  • History of medical illness
  • Smoker within six months prior to the start of the study
  • Abuse of drugs, medicine or alcohol
  • Participation in another study up to two months before study onset
  • No signed consent form before the onset of the experiment
  • Blood donors in the past three months before the onset of the experiment
  • Vegetarian and Vegans
  • Migraines
  • History of orthostatic intolerance
  • History of vestibular disorders
  • Claustrophobia
  • metallic implants, osteosynthesis material
  • Chronic back pain

Sites / Locations

    Arms of the Study

    Arm 1

    Arm 2

    Arm 3

    Arm Type

    Active Comparator

    Experimental

    Active Comparator

    Arm Label

    Hypoxic ambulatory

    Hypoxic Bedrest

    Normoxic bedrest

    Arm Description

    Ambulatory in normobaric hypoxia

    Bedrest in normobaric hypoxia

    Bedrest in normobaric normoxia

    Outcomes

    Primary Outcome Measures

    Postprandial whole blood glucose concentration
    a fasted sample and a sample taken every 10mins for 2hrs following eating, before and after 17days of intervention

    Secondary Outcome Measures

    Postprandial serum insulin concentration
    a fasted sample and a sample taken every 20mins for 2hrs following eating, before and after 17days of intervention
    Postprandial serum C-Peptide concentration
    a fasted sample and a sample taken every 20mins for 2hrs following eating, before and after 17days of intervention
    Fasting serum leptin concentration
    Early morning fasted sample taken before and on day 17 of intervention
    Fasting serum adiponectin concentration
    Early morning fasted sample taken before and on day 17 of intervention
    Fasting serum total cholesterol concentration
    Early morning fasted sample taken before and on day 17 of intervention
    Fasting serum LDL cholesterol concentration
    Early morning fasted sample taken before and on day 17 of intervention
    Fasting serum HDL cholesterol concentration
    Early morning fasted sample taken before and on day 17 of intervention
    Fasting plasmaTriacylglycerol concentration
    Early morning fasted sample taken before and on day 17 of intervention
    Fasting plasma non-esterified fatty acids concentration
    Early morning fasted sample taken before and on day 17 of intervention
    Postprandial plasma peptide YY concentration
    a fasted sample and a sample taken every 20mins for 2hrs following eating, before and after 17days of intervention
    Postprandial plasma Ghrelin concentration
    a fasted sample and a sample taken every 20mins for 2hrs following eating, before and after 17days of intervention
    Postprandial plasma GLP-1 concentration
    a fasted sample and a sample taken every 20mins for 2hrs following eating, before and after 17days of intervention
    Postprandial plasma catecholamine concentration
    a fasted sample and a sample taken every 20mins for 2hrs following eating, before and after 17days of intervention
    Postprandial whole blood lactate concentration
    a fasted sample and a sample taken every 10mins for 2hrs following eating, before and after 17days of intervention
    postprandial fuel oxidation
    A fasted measurement of respiratory exchange ratio and measures between 15-30, 45-60min, 75-90min and 105-120min after eating, before and on day 17 of intervention
    postprandial resting energy expenditure
    A fasted measurement of resting energy expenditure and measures between 15-30, 45-60min, 75-90min and 105-120min after eating, before and on day 17 of intervention
    postprandial subjective appetite
    A fasted measurement of combined appetite score (measured using visual analogue scales), followed by assessment every 30min for 2hrs after eating, before and on day 17 of intervention.
    postprandial expired 13CO2
    Collection of breath samples when fasted and every 30min for 2hrs after eating, before and on day 17 of intervention.

    Full Information

    First Posted
    November 13, 2014
    Last Updated
    March 13, 2019
    Sponsor
    University of Nottingham
    Collaborators
    Jozef Stefan Institute, KTH Royal Institute of Technology, European Commission
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    1. Study Identification

    Unique Protocol Identification Number
    NCT02293772
    Brief Title
    Planetary Habitat Simulation: Nutrition Studies
    Acronym
    PlanHab
    Official Title
    Planetary Habitat Simulation: An Investigation Into the Effects of Hypoxia and / or Bedrest on Fuel Metabolism and Appetite (WP5)
    Study Type
    Interventional

    2. Study Status

    Record Verification Date
    March 2019
    Overall Recruitment Status
    Completed
    Study Start Date
    March 2012 (undefined)
    Primary Completion Date
    November 2013 (Actual)
    Study Completion Date
    October 2014 (Actual)

    3. Sponsor/Collaborators

    Responsible Party, by Official Title
    Principal Investigator
    Name of the Sponsor
    University of Nottingham
    Collaborators
    Jozef Stefan Institute, KTH Royal Institute of Technology, European Commission

    4. Oversight

    Data Monitoring Committee
    Yes

    5. Study Description

    Brief Summary
    A loss of body weight has been documented in lowland-living individuals when exposed to hypoxic environments, such as at high altitude, or under laboratory conditions. A reduction in appetite and energy intake has also been reported during conditions of microgravity, such as during space flight. Fourteen normal or over-weight men, who are otherwise healthy, will undergo 3x 21-day interventions; normobaric normoxic bed rest (NBR; FiO2=21%), normobaric hypoxic ambulatory confinement (HAMB; FiO2=14%; ~4000 m simulated altitude), and normobaric hypoxic bed rest (HBR; FiO2=14%). The effects of hypoxia and bedrest on appetite and its hormonal control will be assessed before and at day 17 of each intervention using a mixed meal tolerance test.
    Detailed Description
    A loss of body weight has been documented in lowland-living individuals when exposed to hypoxic environments, such as at high altitudes, or under laboratory conditions. This weight loss has been attributed both to a reduced appetite (and subsequent fall in dietary energy intake), and to an increase in resting energy expenditure. Interestingly, a reduction in appetite and energy intake has also been reported during space flight, although the mechanism for this has not been explained. As the gas inside future planetary habitats is likely to have lower partial pressure of oxygen than in Earth's atmospheric air, hypoxia induced appetite reduction could pose a challenge for individuals in these environments. For example, persistent under-eating could compromise long term health due to inadequate intake of essential micronutrients, especially in the presence of altered nutrient metabolism and requirements seen during space flight. Moreover, inadequate macronutrient intake could exacerbate the loss of lean body tissue which occurs in situations (such as microgravity, inactivity and bed rest) where muscles are unloaded. Indeed, a protein intake greater than normal could be required in situations where there is muscle inactivity, to achieve the same postprandial anabolic effect of amino acids seen in ambulatory individuals. The mechanism for the reduction in appetite observed in hypoxia is not well established. Several incretin hormones and adipokines have been implicated in the control of appetite and may be candidates for inducing this alteration in appetite observed in hypoxia. However, reports in the literature present contradictory findings, perhaps due to the use of different experimental paradigms (hypobaric and normobaric hypoxia, active and resting subjects, variability in the degree and duration of hypoxia). The protocol of the current study standardises physical activity, ambient temperature, hypoxic stimulus and nutritional composition of the diet, and aims to extend our knowledge of the effects of hypoxia and bedrest on appetite and its hormonal control. In order to discern the separate and combined effects of microgravity and hypoxia, fourteen normal or over-weight men, who are otherwise healthy, will be recruited following medical and psychological screening. They will be invited to attend the Olympic Sport Centre, Planica, Slovenia on 3 occasions, with each visit being 31 days in duration and separated by 5 months. Each 31-day visit ('campaign') includes a baseline recording period (5 days), 21 days of intervention and a recovery period (5 days), with the 3 interventions allocated in a randomized, cross over design: i) Normobaric normoxic bed rest (NBR; FiO2=21%), ii) Normobaric hypoxic ambulatory confinement (HAMB; FiO2=14%; ~4000 m simulated altitude), and iii) Normobaric hypoxic bed rest (HBR; FiO2=14%). A standardized, repeating, 14-day dietary menu, comprised of foods commonly consumed in the Slovenian diet, will be applied during all campaigns, the targeted energy intakes being calculated individually using a modified Benedict-Harris formula with physical activity factor multipliers of 1.2 for the HBR and NBR campaigns and 1.4 for the HAMB campaign. Food will be provided in weighed portions and subjects will be encouraged to eat all food supplied. However, any food not eaten will be weighed and actual amount consumed recorded in a diet analysis programme. Body mass will be assessed daily during the campaigns using a gurney incorporating load cells, and whole body composition will be determined before and immediately after each intervention using fan beam dual-emission X-ray absorptiometry. Participants will undergo a mixed meal tolerance test before and on day 17 of each intervention period, in the morning, after a 12 hour fast, with the time of assessment replicated on each study day at every campaign. On arrival, participants will rest supine on a hospital bed and place their hand in a heated hand warming unit (air temperature 50-55oC). An intravenous cannula will then be inserted retrograde into a dorsal hand vein for arterialised-venous blood sampling. After 15mins rest, a baseline, fasting blood sample will be taken for determination of serum insulin, total cholesterol, high density lipoprotein (HDL) cholesterol, low density lipoprotein (LDL) cholesterol, adiponectin and leptin, whole blood glucose and lactate, and plasma catecholamines, ghrelin, PeptideYY (PYY), glucagon-like peptide-1(GLP-1), triglycerides, and non-esterified fatty acid concentration. An expired breath sample will be collected into evacuated tubes for 13 labelled carbon dioxide (13CO2) determination, and a 20min baseline measurement of resting energy expenditure (REE) and respiratory exchange ratio (RER) will be then made using indirect calorimetry, with subjects wearing a mask, and both inspired and expired air being measured on every breath. Appetite assessment will be made by asking subjects to rate their hunger, desire to eat, fullness, and their prospective food intake, by placing a vertical mark on a 0-100mm linear scale. This visual analogue scale will be measured from left to right, with 0 indicating no experience of the variable (e.g. not hungry, unable to eat anything) and 100 indicating the most of each variable that they can imagine experiencing (e.g. intense desire to eat, or completely full). Values for these 4 variables will be combined to calculate a combined appetite score (CAS). Once baseline measurements have been completed, subjects will consume a mixed nutrient milkshake (Ensure Plus, Abbott Nutrition) at 5ml/kg body weight, which will be supplemented (at 1% of carbohydrate content) with 13-Carbon labelled (13C) Glucose. Arterialised venous blood samples will subsequently be taken every 10min for glucose and lactate assessment, and every 20min for assessment of serum insulin and incretin hormones. A measurement of REE and RER will be performed in the last 15min of every 30min period for the following 2 hours to assess fuel oxidation and metabolic rate, and an expired breath sample will be collected into evacuated tubes for 13CO2 determination at a later date. Subjective appetite will be assessed every 15minutes throughout using visual analogue scales, as described above, and at the end of the 2hr postprandial period subjects will be given an ad libitum pasta-based test meal and will be instructed to eat until they feel comfortably full. This meal will be comprised of cooked dried white pasta, commercially available tomato-based pasta sauce, olive oil and grated hard cheese, with a composition of 37% of total energy derived from fat, 48% carbohydrate, and 16% protein. The amount eaten will be recorded and related to subjective appetite ratings.

    6. Conditions and Keywords

    Primary Disease or Condition Being Studied in the Trial, or the Focus of the Study
    Hypoxia
    Keywords
    Bedrest, Appetite

    7. Study Design

    Primary Purpose
    Basic Science
    Study Phase
    Not Applicable
    Interventional Study Model
    Crossover Assignment
    Masking
    None (Open Label)
    Allocation
    Randomized
    Enrollment
    14 (Actual)

    8. Arms, Groups, and Interventions

    Arm Title
    Hypoxic ambulatory
    Arm Type
    Active Comparator
    Arm Description
    Ambulatory in normobaric hypoxia
    Arm Title
    Hypoxic Bedrest
    Arm Type
    Experimental
    Arm Description
    Bedrest in normobaric hypoxia
    Arm Title
    Normoxic bedrest
    Arm Type
    Active Comparator
    Arm Description
    Bedrest in normobaric normoxia
    Intervention Type
    Other
    Intervention Name(s)
    Hypoxic ambulatory
    Intervention Description
    21 days confinement in normobaric hypoxic (FiO2 = 14%) environment
    Intervention Type
    Other
    Intervention Name(s)
    Hypoxic Bedrest
    Intervention Description
    21 days supine bedrest in normobaric hypoxic (FiO2 = 14%) environment
    Intervention Type
    Other
    Intervention Name(s)
    Normoxic Bedrest
    Intervention Description
    21 days supine bedrest in normobaric normoxic (FiO2 = 21%) environment
    Primary Outcome Measure Information:
    Title
    Postprandial whole blood glucose concentration
    Description
    a fasted sample and a sample taken every 10mins for 2hrs following eating, before and after 17days of intervention
    Time Frame
    2hrs
    Secondary Outcome Measure Information:
    Title
    Postprandial serum insulin concentration
    Description
    a fasted sample and a sample taken every 20mins for 2hrs following eating, before and after 17days of intervention
    Time Frame
    2hrs
    Title
    Postprandial serum C-Peptide concentration
    Description
    a fasted sample and a sample taken every 20mins for 2hrs following eating, before and after 17days of intervention
    Time Frame
    2hrs
    Title
    Fasting serum leptin concentration
    Description
    Early morning fasted sample taken before and on day 17 of intervention
    Time Frame
    early morning fasted sample
    Title
    Fasting serum adiponectin concentration
    Description
    Early morning fasted sample taken before and on day 17 of intervention
    Time Frame
    early morning fasted sample
    Title
    Fasting serum total cholesterol concentration
    Description
    Early morning fasted sample taken before and on day 17 of intervention
    Time Frame
    early morning fasted sample
    Title
    Fasting serum LDL cholesterol concentration
    Description
    Early morning fasted sample taken before and on day 17 of intervention
    Time Frame
    early morning fasted sample
    Title
    Fasting serum HDL cholesterol concentration
    Description
    Early morning fasted sample taken before and on day 17 of intervention
    Time Frame
    early morning fasted sample
    Title
    Fasting plasmaTriacylglycerol concentration
    Description
    Early morning fasted sample taken before and on day 17 of intervention
    Time Frame
    early morning fasted sample
    Title
    Fasting plasma non-esterified fatty acids concentration
    Description
    Early morning fasted sample taken before and on day 17 of intervention
    Time Frame
    early morning fasted sample
    Title
    Postprandial plasma peptide YY concentration
    Description
    a fasted sample and a sample taken every 20mins for 2hrs following eating, before and after 17days of intervention
    Time Frame
    2hrs
    Title
    Postprandial plasma Ghrelin concentration
    Description
    a fasted sample and a sample taken every 20mins for 2hrs following eating, before and after 17days of intervention
    Time Frame
    2hrs
    Title
    Postprandial plasma GLP-1 concentration
    Description
    a fasted sample and a sample taken every 20mins for 2hrs following eating, before and after 17days of intervention
    Time Frame
    2hrs
    Title
    Postprandial plasma catecholamine concentration
    Description
    a fasted sample and a sample taken every 20mins for 2hrs following eating, before and after 17days of intervention
    Time Frame
    2hrs
    Title
    Postprandial whole blood lactate concentration
    Description
    a fasted sample and a sample taken every 10mins for 2hrs following eating, before and after 17days of intervention
    Time Frame
    2hrs
    Title
    postprandial fuel oxidation
    Description
    A fasted measurement of respiratory exchange ratio and measures between 15-30, 45-60min, 75-90min and 105-120min after eating, before and on day 17 of intervention
    Time Frame
    2hrs
    Title
    postprandial resting energy expenditure
    Description
    A fasted measurement of resting energy expenditure and measures between 15-30, 45-60min, 75-90min and 105-120min after eating, before and on day 17 of intervention
    Time Frame
    2hrs
    Title
    postprandial subjective appetite
    Description
    A fasted measurement of combined appetite score (measured using visual analogue scales), followed by assessment every 30min for 2hrs after eating, before and on day 17 of intervention.
    Time Frame
    2hrs
    Title
    postprandial expired 13CO2
    Description
    Collection of breath samples when fasted and every 30min for 2hrs after eating, before and on day 17 of intervention.
    Time Frame
    2hrs

    10. Eligibility

    Sex
    Male
    Minimum Age & Unit of Time
    25 Years
    Maximum Age & Unit of Time
    45 Years
    Accepts Healthy Volunteers
    Accepts Healthy Volunteers
    Eligibility Criteria
    Inclusion Criteria: Physically and mentally healthy subjects Body mass index < 25 kg/m2 Height 158 - 190 cm Waist circumference < 94 cm Volunteers that are able to declare their willingness to participate in the entire study Willing to be assigned randomly to the three groups Successfully passing the psychological and medical screening competent to sign informed consent Slovenian social insurance English language fluency Exclusion Criteria: Medication required that may interfere with the interpretation of the results Bone mineral density (as measured by DEXA) more than 1.5 standard deviations < t score Recent sub-standard nutritional status Family history of thrombosis or positive response in thrombosis screening procedure. (Biochemical analysis of the following parameters: ATIII, High sensitive C-reactive protein, S-Akt., Factor V-Leiden, Prothrombin, Lupus-partial thromboplastin time, Factor II) History of: thyroid dysfunction, renal stones, diabetes, allergies, hypertension, hypocalcemia, uric acidaemia, lipidaemia, or hyperhomocysteinaemia Gastro-esophageal reflux disease or renal function disorder, Hiatus hernia History of medical illness Smoker within six months prior to the start of the study Abuse of drugs, medicine or alcohol Participation in another study up to two months before study onset No signed consent form before the onset of the experiment Blood donors in the past three months before the onset of the experiment Vegetarian and Vegans Migraines History of orthostatic intolerance History of vestibular disorders Claustrophobia metallic implants, osteosynthesis material Chronic back pain
    Overall Study Officials:
    First Name & Middle Initial & Last Name & Degree
    Igor Mekjavic, PhD
    Organizational Affiliation
    Jozef Stefan Institute
    Official's Role
    Principal Investigator

    12. IPD Sharing Statement

    Plan to Share IPD
    No
    Citations:
    PubMed Identifier
    26769956
    Citation
    Simpson EJ, Debevec T, Eiken O, Mekjavic I, Macdonald IA. PlanHab: the combined and separate effects of 16 days of bed rest and normobaric hypoxic confinement on circulating lipids and indices of insulin sensitivity in healthy men. J Appl Physiol (1985). 2016 Apr 15;120(8):947-55. doi: 10.1152/japplphysiol.00897.2015. Epub 2016 Jan 14.
    Results Reference
    result
    PubMed Identifier
    25091855
    Citation
    Debevec T, Bali TC, Simpson EJ, Macdonald IA, Eiken O, Mekjavic IB. Separate and combined effects of 21-day bed rest and hypoxic confinement on body composition. Eur J Appl Physiol. 2014 Nov;114(11):2411-25. doi: 10.1007/s00421-014-2963-1. Epub 2014 Aug 5.
    Results Reference
    result
    PubMed Identifier
    27395413
    Citation
    Debevec T, Simpson EJ, Mekjavic IB, Eiken O, Macdonald IA. Effects of prolonged hypoxia and bed rest on appetite and appetite-related hormones. Appetite. 2016 Dec 1;107:28-37. doi: 10.1016/j.appet.2016.07.005. Epub 2016 Jul 6.
    Results Reference
    result

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    Planetary Habitat Simulation: Nutrition Studies

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