Exercise Training and Blood Vessel Function in Obese Adults

AI summary

From the trial's eligibility criteria. Machine-read from the registry text on this page, so it can be wrong. The registry text below and the trial team decide who can take part.

The trial is looking for sedentary, weight-stable obese adults aged 18 to 45 with the Metabolic Syndrome. It studies muscle blood vessel function and exercise training.

Age

18 Years to 45 Years

Sex

All sexes. Women must be premenopausal and on combined estrogen/progestin hormonal contraception.

Disease stage

Obesity with the Metabolic Syndrome (at least three of the listed features, such as large waist, high triglycerides, low HDL cholesterol, raised blood pressure or raised fasting blood glucose). Sedentary.

Earlier treatment

Weight stable for the past 6 months. No antioxidant, herbal or vitamin supplements for at least 2 weeks before. No regular endurance exercise training.

Biomarker or test result

Metabolic Syndrome measures: waist size, fasting triglycerides above 150 mg/dL (1.7 mmol/L), HDL cholesterol (men below 40 mg/dL (1 mmol/L), women below 50 mg/dL (1.3 mmol/L)), blood pressure above 130/85 mmHg, fasting glucose above 110 mg/dL (6.1 mmol/L).

Main reasons for not taking part

• Diabetes (fasting blood glucose above 125 mg/dL (6.9 mmol/L)) or hypertension above 160/95 mmHg
• Pregnant or breastfeeding
• Smokers or tobacco chewers
• Heart failure, angina, peripheral vascular disease or serious heart rhythm problems
• Taking anti-inflammatory drugs, serotonin reuptake inhibitors or medicines that affect circulation

The registry criteria, word for word

Check if you might fit

Answer for yourself. This is not a decision: only the study team can say whether you can take part.

• Are you between 18 and 45 years old?YesNo

What the trial wants to find out

Impaired endothelial function is observed in disease states related to obesity, such as atherosclerosis, coronary artery disease, and diabetes. Reactive oxygen species (ROS) production and resultant oxidative stress contribute to the development of these obesity-related diseases. The enzyme NADPH-oxidase is a major source of oxidative stress within the vasculature, and has been linked with the Metabolic Syndrome. In the investigator's previously funded studies, the investigators demonstrated for the first time that: 1) in vivo ROS were elevated in skeletal muscle of obese as compared to lean or overweight human subjects, 2) perfusion of the NADPH-oxidase inhibitor apocynin locally into muscle normalized ROS levels and reversed local microvascular endothelial dysfunction in the obese individuals, and 3) aerobic exercise training was effective at attenuating in vivo hydrogen peroxide production and reversing microvascular endothelial dysfunction in the obese individuals. The investigators will investigate in this R15 renewal application the mechanism of exercise training-induced alterations in ROS production and action on endothelial dysfunction in obesity using our newly developed microdialysis methodology of monitoring ROS production, in combination with analysis of muscle biopsy samples obtained before and after our previously tested 8-week intervention of aerobic interval exercise training. The objectives of this study are to determine the impact of in vivo NADPH oxidase activity on endothelial function in obese individuals, and to determine the mechanism of training-induced improvements in endothelial function. The investigator's unique microdialysis methodology will allow monitoring of microvascular/endothelial function and ROS generation, as well as the administration of pharmacological agents directly into muscle. The central hypothesis is that it is upregulation of both mitochondrial ROS and NADPH oxidase-derived ROS that results in endothelial dysfunction in obesity, and that exercise training down-regulates mitochondrial-derived ROS, and NADPH oxidase 4, thereby improving endothelial function. The aims of this proposal are to: 1) determine the contributions of mitochondrial ROS and specific NADPH oxidase isoforms to the NADPH oxidase dependent endothelial dysfunction in skeletal muscle of obese individuals; 2) determine the mechanism of ROS reduction and improved endothelial function resulting from an 8-week aerobic interval training program.

The group in the trial

• Exercise trainingTreatment being tested

  Eight weeks of interval exercise training

  Treatment: Exercise