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

Obesity Clinical Trial

Official title:

Vitamin K and Glucose Metabolism in Adults at Risk for Diabetes

Clinical Trial Details — Status: Active, not recruiting

Administrative data

• NCT number: NCT02366481
• Other study ID #: 620511
• Secondary ID: 16GRNT31090037
• Status: Active, not recruiting
• Phase: N/A
• Start date: February 2015
• Est. completion date: June 30, 2020

Study information

• Verified date: November 2019
• Source: Augusta University
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial 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.

Recruitment information / eligibility

• Status: Active, not recruiting
• Enrollment: 30
• Est. completion date: June 30, 2020
• Est. primary completion date: June 1, 2020
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: All
• Age group: 18 Years to 65 Years

Eligibility

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

Related Conditions & MeSH terms

• Beta-Cell Dysfunction
• Glucose Intolerance
• Hypersensitivity
• Insulin Resistance
• Insulin Sensitivity
• Obesity
• Prediabetes
• Prediabetic State

Intervention

Dietary Supplement:
• Placebo
Two placebo softgel capsules (containing no vitamin K2) every day for 8 weeks.
• 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.
• High-Dose Vitamin K2 Supplement (menaquinone-7; 180-mcg/d)
Two 90-mcg vitamin K2 softgel capsules every day for 8 weeks.

Locations

Country	Name	City	State
United States	Medical College of Georgia; Augusta University	Augusta	Georgia

Sponsors (4)

Lead Sponsor	Collaborator
Augusta University	Tufts University, University of Alabama at Birmingham, Yale University

Country where clinical trial is conducted

United States, 

References & Publications (4)

Booth SL, Centi A, Smith SR, Gundberg C. The role of osteocalcin in human glucose metabolism: marker or mediator? Nat Rev Endocrinol. 2013 Jan;9(1):43-55. doi: 10.1038/nrendo.2012.201. Epub 2012 Nov 13. Review. — View Citation

Gower BA, Pollock NK, Casazza K, Clemens TL, Goree LL, Granger WM. Associations of total and undercarboxylated osteocalcin with peripheral and hepatic insulin sensitivity and ß-cell function in overweight adults. J Clin Endocrinol Metab. 2013 Jul;98(7):E1173-80. doi: 10.1210/jc.2013-1203. Epub 2013 Apr 24. Erratum in: J Clin Endocrinol Metab. 2016 May;101(5):2265. — View Citation

Pollock NK, Bernard PJ, Gower BA, Gundberg CM, Wenger K, Misra S, Bassali RW, Davis CL. Lower uncarboxylated osteocalcin concentrations in children with prediabetes is associated with beta-cell function. J Clin Endocrinol Metab. 2011 Jul;96(7):E1092-9. doi: 10.1210/jc.2010-2731. Epub 2011 Apr 20. — View Citation

Pollock NK. Childhood obesity, bone development, and cardiometabolic risk factors. Mol Cell Endocrinol. 2015 Jul 15;410:52-63. doi: 10.1016/j.mce.2015.03.016. Epub 2015 Mar 27. Review. — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Change in insulin sensitivity	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.	Change from baseline in insulin sensitivity at 8 weeks
Primary	Change in beta-cell function	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.	Change from baseline in beta-cell function at 8 weeks
Secondary	Change in prothrombin time (PT)		Change from baseline in PT at 8 weeks
Secondary	Change in activated partial thromboplastin time (aPTT)		Change from baseline in aPTT at 8 weeks
Secondary	Change in arterial stiffness (PWV)	Arterial stiffness will be assessed using carotid-femoral pulse wave velocity (PWV) by applanation tonometry.	Change from baseline in arterial stiffness at 8 weeks
Secondary	Change in endothelial function (FMD)	Endothelial function will be assessed using brachial artery flow-mediated dilation (FMD) by ultrasound.	Change from baseline in endothelial function at 8 weeks