MitoQ to Improve Vascular Funciton in Preeclampsia

Overview

Preeclampsia is a leading cause of maternal and neonatal morbidity and mortality. There is a lack of effective therapeutics for prevention or treatment. Our previous ex vivo work demonstrated that mitochondrial-antioxidants can reverse placental microvascular damage. Therefore, this study will evaluate whether MitoQ (Mitoquinol Mesylate, a mitochondrial-antioxidant) has the potential to restore vasodilation, improve placental function, and therefore promote pregnancy prolongation in patients with preeclampsia. This evaluation of clinical data, patient samples, and vascular function studies in patients with preeclampsia could translate into a viable therapeutic option.

Preeclampsia (PreE) impacts \~10% of pregnancies and has severe outcomes both during and after pregnancy. It is a leading cause of pregnancy-related deaths, and has long term cardiovascular consequences for maternal and child health. Despite advances in our understanding of preeclampsia over the past 50 years, the underlying unifying mechanism causing preeclampsia remains elusive. This critical gap not only encompasses lack of understanding of the pathophysiology, but it also includes a lack of therapeutics for prevention or treatment. Success in this study could translate into a clinical trial that could finally offer a treatment for PreE. We have recently demonstrated that endothelial function in the human placental microcirculation is impacted by excess reactive oxygen and nitrogen species (ROS, RNS) from the mitochondria (MT), which in preeclampsia, impairs vasodilation. Excess ROS causes decreased nitric oxide (NO) bioavailability, increased lipid peroxidation, uncoupled eNOS, peroxynitrite, and exacerbates MT dysfunction and MT DNA damage via alterations in NO. Microvascular function can be improved by mechanisms that rebalance the oxidative stress response. We have shown that MitoTempol, a MT antioxidant, improves vasodilation. Moreover, we have shown that a major part of the cycle of excessive oxidative stress is caused by MT DNA damage and subsequent activation of toll like receptor 9 (TLR9), and that inhibiting TLR9 prevents this dysfunction. The finding that MT antioxidants given ex-vivo can reverse placental vascular damage after delivery gives promise that treatment of patients during pregnancy could restore vasodilation and allow for safer prolongation of pregnancy. MitoQ (Mitoquinol Mesylate) is a nutritional supplement, and mitochondrial antioxidant. MitoQ has been extensively studied pre- clinically in cell-culture, and pregnant mouse, rat, and sheep models of PreE or oxidative stress and demonstrated beneficial fetal results. It has been used in clinical trials for heart failure, hepatitis C, Parkinson's, and multiple sclerosis with doses from 10mg to 80mg per day. Overall Hypothesis: We hypothesize that MitoQ (Mitoquinol Mesylate)-treated preeclampsia patients will have improved brachial artery flow-mediated dilation (FMD) and laser Doppler flowmetry assessments of the cutaneous microvasculature, and that placental endothelial function in micro-vessels and placental pathology will be improved in treated patients. To demonstrate this, we will enroll two pilot human cohorts- one of admitted patients with preeclampsia with severe features who will either continue standard in-patient clinical care or be supplemented daily with MitoQ (Mitoquinol Mesylate) and a second outpatient cohort of patients with preeclampsia without severe features who will received standard outpatient care or be supplemented daily with MitoQ Aim: Test whether with MitoQ (Mitoquinol Mesylate) treatment in preeclamptic patients improves endothelial function Hypothesis: MitoQ (Mitoquinol Mesylate)-treated patients will have improved brachial artery FMD and laser Doppler flowmetry assessments of the cutaneous microvasculature and placental endothelial function in micro-vessels and placental pathology will be improved in treated patients.