Endothelial Function

This randomized, double-blind, controlled clinical trial will evaluate the effects of daily cocoa flavanol supplementation on vascular and inflammatory biomarkers in healthy adult men aged 30 to 75 years. Participants will be randomized to receive either a cocoa flavanol supplement or a nutrient-matched low-flavanol control product for 4 to 8 weeks. The study will assess changes in inflammatory biomarkers, endothelial function, oxidative stress markers, vascular measurements, and circulating endothelial progenitor cell-related markers. Optional assessments include flow-mediated dilation and single-cell RNA sequencing of peripheral blood mononuclear cells to explore mechanistic biological responses to cocoa flavanol supplementation.

Preeclampsia is a condition in pregnancy where a woman develops high blood pressure and other complications. Women who develop preeclampsia are 4 times more likely to have heart disease later in life. They are also more likely to have depression after pregnancy. Why they are more likely to develop these conditions is not known. It may be because their blood vessels were damaged during pregnancy. Changes in blood vessel health can predict heart disease. These changes have been recorded after pregnancy in women who had preeclampsia. These changes have also been recorded in women who have depression. In the previous phase of this award, we found that women who had preeclampsia in pregnancy had changes in blood vessel health after pregnancy. We also found that if these women were taking a medicine to treat depression, their blood vessel health was normal. This could mean that treatment for depression can also increase blood vessel health in women who had preeclampsia. In this project we will study how changes in blood vessel health are related to preeclampsia and depression in women who have had both. We will also study how medicine to treat depression can improve blood vessel health after preeclampsia. We will do this by measuring how blood vessels work in women who have had preeclampsia compared to women who did not, and in women who have depression and women who do not. This will tell us more about why risk for depression and heart disease is higher in women who have had preeclampsia. It will also help us understand if medicine for depression can reduce cardiovascular disease risk after preeclampsia.

Hypertension is associated with endothelial dysfunction, an early event in the development of cardiovascular disease. Endothelial extracellular vesicles (EEVs) have emerged as promising biomarkers of endothelial activation and vascular injury; however, their relationship with blood pressure and microvascular endothelial function in untreated hypertension remains insufficiently understood. This observational case-control study aims to compare circulating EEV concentrations between normotensive adults and adults with newly diagnosed, untreated primary hypertension. In addition, the study will investigate the associations between EEV levels, blood pressure, microvascular endothelial function assessed by laser Doppler flowmetry, and established circulating biomarkers of endothelial activation. The findings may improve understanding of the role of EEVs in early hypertension and support their potential use as non-invasive biomarkers of endothelial dysfunction and cardiovascular risk.

This study aims to investigate the impact of platelet concentrate (PC) transfusions on endothelial function and the systemic inflammatory response in thrombopenic patients admitted to intensive care who require prophylactic platelet transfusions. Endothelial function will be measured using a laser Doppler device coupled with an acetylcholine iontophoresis system that is applied to the skin.

The increase in skin blood flow in response to rapid local heating of the skin (i.e., cutaneous vasodilation) is commonly used to assess nitric oxide (NO)-dependent dilation and overall microvascular function. Historically, rapid local heating to 42°C was considered the standard approach for these assessments. More recently, many investigators have adopted rapid local to 39°C instead, based on its larger dependency on NO and therefore improved ability to quantify NO-dependent dilation without the use of pharmacological techniques. However, to date, only one direct methodological comparison between these protocols has been performed. In this study, the investigators use the blood vessels in the skin as a representative vascular bed for examining mechanisms of microvascular dysfunction in humans. Using a minimally invasive technique (intradermal microdialysis for the local delivery of pharmaceutical agents) they examine the blood vessels in a nickel-sized area of the skin in young adults ages 18 - 30 years old. Local heating of the skin at the microdialysis sites is used to explore differences in mechanisms governing microvascular control. As a compliment to these measurements, the investigators also have participants fill out a variety of surveys to assess things such as sleep quality, physical activity, daily stressors, etc.