THE INCREASE IN CARDIOVASCULAR DISEASE RISK WITH AGING ACCELERATES AFTER MENOPAUSE IN WOMEN. THE INCREASED RISK WITH AGING IS LARGELY DUE TO THE DEVELOPMENT OF VASCULAR ENDOTHELIAL DYSFUNCTION. RESEARCH INDICATES THAT ENDOTHELIAL DYSFUNCTION IS MEDIATED BY THE GUT MICROBIOME AND THEREFORE REPRESENTS A NOVEL THERAPEUTIC TARGET. BLUEBERRIES ARE A PROMISING FUNCTIONAL FOOD FOR CARDIOVASCULAR HEALTH, AND RESEARCH SUGGESTS THEY CAN MODULATE THE GUT MICROBIOTA. WE PREVIOUSLY DEMONSTRATED THAT 8 WEEKS BLUEBERRY CONSUMPTION REDUCED BLOOD PRESSURE AND ARTERIAL STIFFNESS IN POSTMENOPAUSAL WOMEN WITH PRE- AND STAGE 1-HYPERTENSION. THE CURRENT PROJECT WILL EXAMINE THE RELATIONSHIP BETWEEN BLUEBERRY CONSUMPTION AND THE GUT MICROBIOME IN PROMOTING CARDIOVASCULAR HEALTH. WE BELIEVE THAT THE ABILITY OF BLUEBERRIES TO IMPROVE ENDOTHELIAL FUNCTION IN POSTMENOPAUSAL WOMEN WITH ELEVATED BLOOD PRESSURE IS DEPENDENT ON THE GUT MICROBIOTA, AND THAT BLUEBERRIES EXERT BENEFICIAL EFFECTS ON THE GUT MICROBIOTATHEREBY IMPROVING THE BENEFICIAL EFFECTS OF BLUEBERRIES ON CARDIOVASCULAR HEALTH OVER TIME. THIS WILL BE TESTED USING A REVERSE TRANSLATIONAL APPROACH IN HUMANS, ANIMALS, AND CELLS. THE PROPOSED STUDIES WILL IMPROVE OUR UNDERSTANDING OF THE IMPACT OF FOODS ON THE HUMAN GUT MICROBIOME WHICH CAN BE UTILIZED IN US AGRICULTURAL AND FOOD SYSTEMS TO IMPROVE FOOD QUALITY TO BETTER PROMOTE HUMAN HEALTH.