Cardiovascular Diseases, Hypertension
Conditions
Brief summary
The main purpose of research is to examine and understanding the development of hypertension in obese adults with insulin resistance. Findings from our studies will identify unique mechanisms that can be targeted to limit increases in vascular dysfunction and reduce the excessively high prevalence of hypertension and risk for cardiovascular disease (CVD). This study is testing the health of the blood vessels and the activity of the nerves that control the blood vessels in adults with insulin resistance. The extent to which ascorbic acid (Vitamin C) improves the function of the blood vessels will be determined. The primary outcome is blood pressure, which is the result of blood vessel health and activity of the nerves, and the reduction in blood pressure that is observed with ascorbic acid.
Interventions
DRUGAscorbic acid solution (American Regent Laboratories Inc.)
Ascorbic acid solution (American Regent Laboratories Inc.) will be obtained from the KU Investigational Pharmacy located in the KU Clinical Research Center where studies will take place. A priming bolus of 0.06 g ascorbic acid/kg fat free mass (FFM) dissolved in 100 mL of saline will be infused intravenously at 5 mL/min for 20 minutes, followed immediately by a drip-infusion of 0.02 g/kg FFM dissolved in 30 mL of saline administered over 2 hours at 0.5 mL/min.
DRUGSaline
Placebo (saline) will be administered
Sponsors
University of Kansas Medical Center
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
DOUBLE (Subject, Investigator)
Eligibility
Sex/Gender
ALL
Age
35 Years to 65 Years
Healthy volunteers
No
Inclusion criteria
1. Obese: BMI \>30 m/kg2 2. Middle-aged: 35-65 years 3. Participants must be willing and able to discontinue taking any vitamin C or E supplements or omega-3 fatty acids beginning 2 weeks prior. 4. Able and willing to provide written informed consent
Exclusion criteria
1. Diabetes mellitus: fasting glucose \< 1267 mg/dL and/or HbA1c \< 6.5% 2. Currently taking a statin or antihypertension medication 3. Hyperlipidemia: Fasting triglycerides \< 250 mg/dL 4. Hypertension: \<130/80 mmHg 5. History of heart disease (e.g., myocardial infarction, stent) 6. History of vascular disease (e.g., bypass, stroke)
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Efficacy of infusion of ascorbic acid | 30 minutes | The difference in sympathetic-vascular transduction (mmHg) between ascorbic acid and placebo infusion will be taken as a measure of the modulation of SVT by oxidative stress. |
Countries
United States
Contacts
Primary ContactSeth Holwerda, PhD
Backup ContactManuel Clark, MPA
Outcome results
None listed