Role of tart cherry in the prevention of hypertension and the modulation of inflammatory signaling
Date
2022
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
University of Delaware
Abstract
Hypertension increases the risk for vascular damage, atherosclerosis, and subsequent cardiovascular disease (CVD) related morbidity and mortalities. The development and progression of several chronic conditions, including hypertension, are influenced by inflammation.Chronic low-grade inflammation and hypertension, both prevalent in the aging population, can be modulated by dietary and lifestyle choices. Our laboratory has previously shown that 12 weeks of tart cherry (TC) juice consumption can reduce systolic BP and markers of inflammation and oxidative stress in older adults. There are several bioactive compounds in TC and evidence suggests these compounds in isolation can influence inflammatory signaling pathways that contribute to the pathogenesis of hypertension. ☐ To first understand the impact of diet on BP, we conducted a cross-sectional study on 128 adults aged 65–80 years. Multiple linear regressions were conducted to examine the influence of major dietary factors on systolic and diastolic BP. We also wanted to understand the role of TC in reducing BP. To study this, human coronary artery endothelial cells (HCAEC) were exposed to 0-500μg/mL of TC extracts in the presence or absence of Angiotensin-II (Ang-II), which is known to increase BP and inflammation. Western blots were used to examine the effects of TC and/or Ang-II on the protein expression of nitric oxide synthases and inflammatory molecules associated with the NF-κB signaling pathway. ☐ Results of the cross-sectional study showed a significant association between intake of added sugar and systolic and diastolic BP in females. Whole fruit consumption was associated with a reduction in diastolic BP in both males and females. The regression model predicted that for every 0.71 cup increase in whole fruit consumption, there would be a 2.8 mmHg reduction in diastolic BP. ☐ In the absence of Ang-II, TC exposure did not influence eNOS expression. Expression of iNOS was reduced by TC at all doses in the absence of Ang-II. Levels of p65 were significantly reduced at 62.5 and 125μg/mL compared to the control. Phosphorylated p65 was upregulated at the 62.5 μg/mL dose and ICAM-1 was similar between groups. In the presence of Ang-II, the 62.5 Ang and 125 Ang exposures resulted in a 0.75 fold and 0.71 fold reduction in iNOS respectively. Ang-II did not significantly affect NOS or inflammatory markers compared to the control. This could be due to the metabolism of Ang-II or loss of Ang-II type 1 receptor in cell culture. ☐ Our findings support increased fruit consumption for the reduction of BP in older adults. Additionally, TC exposure can reduce the expression of iNOS which is known to contribute to the development of hypertension.
Description
Keywords
Tart cherry, Hypertension, Cardiovascular disease, Diastolic BP, Older adults