Project Number: 8050-51000-102-009-A
Project Type: Cooperative Agreement
Start Date: Jul 1, 2018
End Date: Oct 31, 2021
There is evidence for short-term (acute) benefits of flavonoid/polyphenol intake on cognition, with changes as early as at 2 hours post-consumption in executive function, and possible further improvements at 5-7 h post intake. Interestingly, increases in flow mediated dilation (FMD) are seen at times similar to peaks in plasma phenolic acids (i.e., 2, 3, and 6 h) after berry consumption, time points that seem to correlate with the appearance of cognitive improvements. Anthocyanins and their phase II metabolites peak ~2-3 h following berry consumption, and late phase anthocyanin and phenolic acid metabolites appear in plasma around 5-6 h post-consumption. Moreover, in this acute time frame, improvements in postprandial inflammatory status and insulin/glucose metabolism have been shown in middle-age overweight and obese individuals eating berries with a typical Western meal. Collectively, the work suggests a relationship between cognitive performance, metabolic control and the pharmacokinetics of anthocyanins. Therefore, the aim of this proposal is to study the relationship between cognitive performance, metabolic control, and the pharmacokinetics of anthocyanins in middle-age to older adults (55-70y) following raspberry consumption. We hypothesize that raspberry supplementation will improve cognition function in older, overweight/obese adults following a meal challenge. We also hypothesize that raspberry supplementation will improve neurovascular and vascular function and reduce inflammation, and these changes will correlate with the improvements in cognition and anthocyanins in plasma.
The proposed research will explore the effects of acute raspberry supplementation in older (55-70 years old), overweight/obese (BMI 27-35) adults in a double-blind, placebo controlled, crossover experimental design. Participants will consume a raspberry or placebo drink with a high-fat meal challenge. Blood will be drawn at baseline, then at 9 time-points over 10 hours. Measures of cognition will be assessed at baseline and then every 2 hours up to 8 hours. Cognition will be assessed through challenging measures of spatial navigation, attention, short- and long-term memory, and executive function. FMD and NIRS will also be assessed (FMD will be conducted by our collaborator at IIT, and NIRS will be conducted in-house with equipment owned by the Neuroscience and Aging Lab). Additionally, plasma measures of inflammation (e.g.,cytokines) will be analyzed. Statistical support for the project will be available through the HNRCA’s Biostatistics and Data Management Core Units. The HNRCA Biostatistics and Data Management Core Unit will help answer statistical questions from the study team and provide statistical support and oversight for the data analysis as well as training in statistical methods relevant to the study. The original proposed plan was for 25 participants to be completed by the HNRCA and 25 participants to be completed by a collaborator at Illinois Institute of Technology. In discussions with the collaborator at IIT, 30 participants collected at the IIT site and 5 participants completed at the HNRCA will be sufficient for this study. Therefore, no additional participants will be enrolled at either site.