Clinical trial NCT02366481: Vitamin K and Glucose Metabolism in Adults at Risk for Diabetes (Vita-K 'n' Adults Study)
Official title: Vitamin K and Glucose Metabolism in Adults at Risk for Diabetes
Study type: INTERVENTIONAL
Overall status: UNKNOWN
Phase: NA
Conditions: Obesity
Insulin Resistance
Insulin Sensitivity
Beta-Cell Dysfunction
Prediabetes
Keywords: Vitamin K
Vitamin K2
Menaquinone-7
Osteocalcin
Adults
Obesity
Insulin resistance
Insulin sensitivity
Beta-cell function
Prediabetes
Lead sponsor: Augusta University
Sponsor class: OTHER
Collaborators: name: University of Alabama at Birmingham
name: Yale University
name: Tufts University
First posted: 2015-02-19
Enrollment: 30
Sex: ALL
Minimum age (years): 18
Maximum age (years): 65
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: PREVENTION

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.


Eligibility 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

Primary outcomes:
measure: Change in insulin sensitivity
timeFrame: Change from baseline in insulin sensitivity at 8 weeks
measure: Change in beta-cell function
timeFrame: Change from baseline in beta-cell function at 8 weeks
Secondary outcomes:
measure: Change in prothrombin time (PT)
timeFrame: Change from baseline in PT at 8 weeks
measure: Change in activated partial thromboplastin time (aPTT)
timeFrame: Change from baseline in aPTT at 8 weeks
measure: Change in arterial stiffness (PWV)
timeFrame: Change from baseline in arterial stiffness at 8 weeks
measure: Change in endothelial function (FMD)
timeFrame: Change from baseline in endothelial function at 8 weeks
Other outcomes:
Locations:
city: Augusta
country: United States
facility: Medical College of Georgia; Augusta University
state: Georgia
Study officials:
affiliation: Department of Pediatrics, Medical College of Georgia, Augusta University
name: Norman K Pollock, Ph.D.
role: PRINCIPAL_INVESTIGATOR
References:
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.
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 beta-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.
citation: 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.
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.