Clinical trial NCT01857258: Green Tea Confections For Managing Postprandial Hyperglycemia-Induced Vascular Endothelial Dysfunction
Official title: Green Tea Confections For Managing Postprandial Hyperglycemia-Induced Vascular Endothelial Dysfunction
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Hyperglycemia
Cardiovascular Disease
Keywords: green tea
catechins
vascular endothelial function
postprandial hyperglycemia
oxidative stress
Lead sponsor: Ohio State University
Sponsor class: OTHER
First posted: 2013-05-20
Enrollment: 15
Sex: MALE
Minimum age (years): 18
Maximum age (years): 30
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Primary purpose: PREVENTION

Brief summary: The objective of this study is to formulate and validate a green tea confection (i.e. "gummy" candy) as a strategy to attenuate postprandial hyperglycemia-induced impairments in vascular function. The central hypothesis is that a green tea confection will protect against vascular endothelial dysfunction by suppressing postprandial hyperglycemia. The central hypothesis of this application will be assessed by developing a green tea-containing confection, examining its physiochemical properties and its inhibition of starch digestion, and then validating its vasoprotective activities in healthy humans by assessing its blood glucose-regulating activities.

Detailed description: The study involves validating a green tea confection (i.e. "gummy" candy) as a dietary strategy to attenuate postprandial hyperglycemia-induced impairments in vascular function. The central hypothesis is that a green tea confection will protect against vascular endothelial dysfunction by suppressing postprandial hyperglycemia. The central hypothesis of this application will be assessed by providing research participants 75 grams of carbohydrate in the form of a confection that contains no green tea concentrate or green tea concentrate at a level equivalent to approximately 3 cups of freshly brewed tea. Blood glucose and brachial artery flow-mediated dilation will be assessed at regular intervals during the 3 hour postprandial period to define the extent to which green tea attenuates postprandial increases in blood glucose and decreases in vascular function that otherwise occur in a hyperglycemia-dependent manner.

Eligibility criteria: Inclusion Criteria:

* Plasma glucose \<100 mg/dL
* Plasma total cholesterol \<200 mg/dL
* Plasma triglycerides \<140 mg/dL
* Blood pressure \<140/90
* non-dietary supplement user for \>2 months
* no use of medications known to affect carbohydrate metabolism,
* nonsmoker / never smoker
* no history of cardiovascular disease or gastrointestinal disorders

Exclusion Criteria:

* allergies or aversions to green tea and/or corn starch,
* excessive alcohol consumption (\>3 drinks/d),
* \>5 h/wk of aerobic activity

Primary outcomes:
measure: Area Under the Curve of Blood Glucose
timeFrame: Area under the Curve, 0, 30, 60, 90, 120, 150, 180 minutes post-dose
measure: Area Under the Curve of Brachial Artery Flow Mediated Dilatiion
timeFrame: Area under the Curve, 0, 30, 60, 90, 120, 150, 180 minutes post-dose
measure: Brachial Artery Flow-mediated Dilation
timeFrame: 0 min (baseline)
measure: Brachial Artery Flow-mediated Dilation
timeFrame: 60 min
Secondary outcomes:
measure: Malondialdehyde (0 Min)
timeFrame: Baseline (0 min)
measure: Malondialdehyde
timeFrame: 60 min postprandially
measure: Ratio of Asymmetric Dimethylarginine Relative to Arginine
timeFrame: 0 min (baseline)
measure: Ratio of Asymmetric Dimethylarginine Relative to Arginine
timeFrame: 60 min (baseline)
Other outcomes:
Locations:
city: Columbus
country: United States
facility: The Ohio State University
state: Ohio
Study officials:
affiliation: Ohio State University
name: Richard Bruno, PhD, RD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Sapper TN, Mah E, Ahn-Jarvis J, McDonald JD, Chitchumroonchokchai C, Reverri EJ, Vodovotz Y, Bruno RS. A green tea-containing starch confection increases plasma catechins without protecting against postprandial impairments in vascular function in normoglycemic adults. Food Funct. 2016 Sep 14;7(9):3843-53. doi: 10.1039/c6fo00639f. Epub 2016 Aug 5.