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Trial record 25 of 50 for:    vitamin k2

Vitamin K and Glucose Metabolism in Adults at Risk for Diabetes (Vita-K 'n' Adults Study)

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ClinicalTrials.gov Identifier: NCT02366481
Recruitment Status : Recruiting
First Posted : February 19, 2015
Last Update Posted : July 12, 2018
Sponsor:
Collaborators:
University of Alabama at Birmingham
Yale University
Tufts University
Nattopharma ASA
Information provided by (Responsible Party):
Norman Pollock, Augusta University

Brief Summary:
Given that glutamate carboxylation or decarboxylation is key to the metabolic role of osteocalcin (at least in mouse models) and that carboxylation is vitamin K dependent, it is critical to isolate the effect of vitamin K manipulation on carboxylation of osteocalcin and its subsequent effect on glucose metabolism in clinical trials. The purpose of this randomized, double-blind, placebo-controlled clinical trial in adults is to determine whether eight weeks of daily supplementation with vitamin K2 (menaquinone-7) can improve markers in blood associated with diabetes risk.

Condition or disease Intervention/treatment Phase
Obesity Insulin Resistance Insulin Sensitivity Beta-Cell Dysfunction Prediabetes Dietary Supplement: Placebo Dietary Supplement: Low-Dose Vitamin K2 Supplement (menaquinone-7; 90-mcg/d) Dietary Supplement: High-Dose Vitamin K2 Supplement (menaquinone-7; 180-mcg/d) Phase 1 Phase 2

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Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 30 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary Purpose: Prevention
Official Title: Vitamin K and Glucose Metabolism in Adults at Risk for Diabetes
Study Start Date : February 2015
Estimated Primary Completion Date : December 1, 2018
Estimated Study Completion Date : December 30, 2018

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Vitamin K
Drug Information available for: Menadione

Arm Intervention/treatment
Placebo Comparator: Placebo-Control
The placebo-control group will take two placebo softgel capsules every day for 8 weeks.
Dietary Supplement: Placebo
Two placebo softgel capsules (containing no vitamin K2) every day for 8 weeks.

Active Comparator: Low-Dose Vitamin K2 (90-mcg/d)
The low-dose vitamin K group will take one 90-mcg vitamin K2 (menaquinone-7) softgel capsule and one placebo softgel capsule every day for 8 weeks.
Dietary Supplement: Low-Dose Vitamin K2 Supplement (menaquinone-7; 90-mcg/d)
One 90-mcg vitamin K2 softgel capsules (containing no vitamin K2) and one placebo softgel capsule everyday for 8 weeks.

Active Comparator: High-Dose Vitamin K2 (180-mcg/d)
The high-dose vitamin K group will take two 90-mcg vitamin K2 (menaquinone-7) softgel capsules every day for 8 weeks.
Dietary Supplement: High-Dose Vitamin K2 Supplement (menaquinone-7; 180-mcg/d)
Two 90-mcg vitamin K2 softgel capsules every day for 8 weeks.




Primary Outcome Measures :
  1. Change in insulin sensitivity [ Time Frame: Change from baseline in insulin sensitivity at 8 weeks ]
    Insulin sensitivity will be calculated from plasma insulin and glucose concentrations measured during a 2-hour oral glucose tolerance test by using the oral glucose minimal model.

  2. Change in beta-cell function [ Time Frame: Change from baseline in beta-cell function at 8 weeks ]
    Beta-cell function, as assessed by dynamic beta-cell responsitivity, will be calculated from plasma glucose and C-peptide concentrations measured during a 2-hour oral glucose tolerance test by using the oral C-peptide minimal model.


Secondary Outcome Measures :
  1. Change in prothrombin time (PT) [ Time Frame: Change from baseline in PT at 8 weeks ]
  2. Change in activated partial thromboplastin time (aPTT) [ Time Frame: Change from baseline in aPTT at 8 weeks ]
  3. Change in arterial stiffness (PWV) [ Time Frame: Change from baseline in arterial stiffness at 8 weeks ]
    Arterial stiffness will be assessed using carotid-femoral pulse wave velocity (PWV) by applanation tonometry.

  4. Change in endothelial function (FMD) [ Time Frame: Change from baseline in endothelial function at 8 weeks ]
    Endothelial function will be assessed using brachial artery flow-mediated dilation (FMD) by ultrasound.



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Ages Eligible for Study:   18 Years to 65 Years   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

  1. Healthy adults between 18 and 65 years old
  2. Subject understands the study protocol and agrees to comply with it
  3. Informed Consent Form signed by the subject

Exclusion Criteria:

  1. Subjects using vitamin supplements containing vitamin k
  2. Subjects with (a history of) metabolic or gastrointestinal diseases including hepatic disorders
  3. Subjects presenting chronic degenerative and/or inflammatory diseases
  4. Subjects receiving systemic treatment or topical treatment likely to interfere with evaluation of the study parameters (salicylates, antibiotics)
  5. Subjects receiving corticosteroid treatment
  6. Subjects using oral anticoagulants
  7. Subjects with a history of soy allergy
  8. Subjects who have participated in a clinical study more recently than one month before the current study

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT02366481


Contacts
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Contact: Norman K Pollock, Ph.D. 706-721-5424 npollock@augusta.edu
Contact: Celestine F Williams, M.S. 706-721-8553 cewilliams@augusta.edu

Locations
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United States, Georgia
Medical College of Georgia; Augusta University Recruiting
Augusta, Georgia, United States, 30912
Contact: Norman K Pollock, Ph.D.    706-721-5424    npollock@augusta.edu   
Sponsors and Collaborators
Augusta University
University of Alabama at Birmingham
Yale University
Tufts University
Nattopharma ASA
Investigators
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Principal Investigator: Norman K Pollock, Ph.D. Department of Pediatrics, Medical College of Georgia, Augusta University

Publications:
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Responsible Party: Norman Pollock, Associate Professor, Department of Pediatrics, Augusta University
ClinicalTrials.gov Identifier: NCT02366481     History of Changes
Other Study ID Numbers: 620511
16GRNT31090037 ( Other Grant/Funding Number: American Heart Association )
First Posted: February 19, 2015    Key Record Dates
Last Update Posted: July 12, 2018
Last Verified: July 2018
Keywords provided by Norman Pollock, Augusta University:
Vitamin K
Vitamin K2
Menaquinone-7
Osteocalcin
Adults
Obesity
Insulin resistance
Insulin sensitivity
Beta-cell function
Prediabetes
Additional relevant MeSH terms:
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Vitamins
Vitamin K
Vitamin K 2
Vitamin MK 7
Insulin Resistance
Prediabetic State
Glucose Intolerance
Hypersensitivity
Immune System Diseases
Hyperinsulinism
Glucose Metabolism Disorders
Metabolic Diseases
Diabetes Mellitus
Endocrine System Diseases
Hyperglycemia
Physiological Effects of Drugs
Micronutrients
Nutrients
Growth Substances
Antifibrinolytic Agents
Fibrin Modulating Agents
Molecular Mechanisms of Pharmacological Action
Hemostatics
Coagulants