Objectives: Biomarkers are often measured to understand potential mechanisms of action in dietary intervention research. Our previous randomized, controlled trial demonstrated that 12 weeks of consumption of tart cherry juice can modulate the levels of systolic blood pressure (SBP). The present study investigated the effects of tart cherry juice on blood biomarkers of inflammation, oxidative stress and endothelial function in older adults.
Methods: Thirty-seven (N=37) participants were randomly assigned to consume 480 ml of tart cherry juice or control drink daily for 12 weeks. Fasting blood samples were collected at baseline and 12 weeks. Blood biomarker of endothelin-1, angiotensin II, nitrite oxide, 8-hydroxydeoxyguanosine (8-OHdG), 8-oxoguanine glycosylase (OGG1) and malondialdehyde (MDA) were assessed. A mixed analysis of variance model was used to examine the effects of time, treatment, and the interaction between time and treatment.
Results: Our findings indicate that after 12 weeks of juice consumption, the DNA repair activity of OGG1 significantly increased in the tart cherry group, as compared to the control group. In addition, a significant main effect of treatment was found in MDA, while a borderline significant effect of time was found in 8-OHdG.
Conclusion: The findings of the present study suggest that the reduction of BP by tart cherry juice may be due, in part, to its anti-oxidative properties.