Location: Obesity and Metabolism Research
Project Number: 2032-51530-025-009-R
Project Type: Reimbursable Cooperative Agreement
Start Date: Jan 15, 2018
End Date: Jan 14, 2023
Objective:
Investigate the effects of consuming cherry powder by overweight human subjects on biomarkers that are associated with clinical end points for metabolic syndrome. Another objective of this work is to test for ameliorating effects of cherries on markers of chronic life stress and stress induced cardiovascular reactions.
Approach:
The metabolic syndrome elevates risk for chronic health problems, including heart disease, stroke, and type 2 diabetes. Metabolic syndrome risk factors are: abdominal obesity, dyslipidemia, high blood pressure, and insulin resistance or poor blood glucose control. Prevalence of metabolic syndrome in the U.S. is about 33%, and metabolic syndrome elevates health care utilization and costs. According to the American Heart Association and the National Heart, Lung, and Blood Institute, lifestyle changes remain to be the most effective and first line strategy for preventing and treating metabolic syndrome and reducing risk for developing heart disease, stroke, and type 2 diabetes. Increased fruit and vegetable consumption may reduce risk of heart disease, stroke, and diabetes. Recent evidence from human clinical studies suggest that consumption of Bing sweet cherries may decrease inflammation, as well as reduce risks for diabetes, cardiovascular disease, and hypertension. Furthermore, factors that mitigate mental stress and its effects throughout the body may provide protection against metabolic syndrome and its associated diseases (e.g., cardiovascular) in people exposed to persistent or acute traumatic stress. Cherry consumption may have anti-stress effects, and these effects may mediate the metabolic and cardiovascular benefits of consuming cherries. More clinical trials are needed to clarify the health promoting benefits of cherry consumption. Therefore, in a placebo controlled, cross over study, we will determine the effects of cherry powder consumption on biomarkers for metabolic syndrome in overweight human subjects, since being overweight increases the chance of having metabolic syndrome In Aim 1, we will assess the effects of cherry powder on cardiovascular health. Cardiovascular health will be assessed by monitoring blood pressure and changes in microvascular function as determined by peripheral arterial tonometry. Blood pressure will be monitor by standard clinical methods. Cardiovascular regulation will be examined by use of MindWare physiological monitoring technology that monitors autonomic nervous system activity. We will also examine if cherry consumption improves cardiovascular reactivity after exposure to an acute mental stress test. We hypothesize that cherry powder will improve cardiovascular functions, under basal and stressful conditions. In Aim 2, we will determine if cherry powder consumption improves insulin resistance (IR). We will determine the effects of cherry and placebo powders on both glucose control/IR and lipid status. Biomarkers examined include fasting glucose, insulin, and HbA1C, homeostasis model of insulin resistance (HOMA-IR), and Matsuda index of insulin sensitivity following the administration of an oral glucose tolerance test (OGTT). Since IR is associated with dyslipidemia, we will also monitor blood lipids, including triglycerides, total LDL- and HDL-cholesterol, free fatty acids, and VLDL, LDL, and HDL particles and their mean sizes as determined by nuclear magnetic resonance (NMR). We hypothesize that cherry powder will improve markers of glucose control.