Sebastian R. Hobson

Phase I pilot clinical trial of antenatal maternally administered melatonin to decrease the level of oxidative stress in human pregnancies affected by pre-eclampsia (PAMPR): study protocol

Introduction Pre-eclampsia is a common pregnancy condition affecting between 3% and 7% of women. Unfortunately, the exact pathophysiology of the disease is unknown and as such there are no effective treatments that exist notwithstanding prompt delivery of the fetus and culprit placenta. As many cases of pre-eclampsia occur in preterm pregnancies, it remains a significant cause of maternal and perinatal morbidity and mortality. Recently, in vitro and animal studies have highlighted the potential role of antioxidants in mitigating the effects of the disease. Melatonin is a naturally occurring antioxidant hormone and provides an excellent safety profile combined with ease of oral administration. We present the protocol for a phase I pilot clinical trial investigating the efficacy and side effects of maternal treatment with oral melatonin in pregnancies affected by preterm pre-eclampsia. Methods and analysis We propose undertaking a single-arm open label clinical trial recruiting 20 women with preterm pre-eclampsia (24+0–35+6 weeks). We will take baseline measurements of maternal and fetal well-being, levels of oxidative stress, ultrasound Doppler studies and other biomarkers of pre-eclampsia. Women will then be given oral melatonin (10 mg) three times daily until delivery. The primary outcome will be time interval between diagnosis and delivery compared to historical controls. Secondary outcomes will compare the baseline measurements previously mentioned with twice-weekly measurements during treatment and then 6 weeks postpartum. Ethics and dissemination Ethical approval has been obtained from Monash Health Human Research Ethics Committee B (HREC 13076B). Data will be presented at international conferences and published in peer-reviewed journals. Trial registration number ACTRN12613000476730 (ANZCTR).

Activin and NADPH-oxidase in preeclampsia: insights from in vitro and murine studies

OBJECTIVE Clinical management of preeclampsia has remained unchanged for almost 5 decades. We now understand that maternal endothelial dysfunction likely arises because of placenta-derived vasoactive factors. Activin A is one such antiangiogenic factor that is released by the placenta and that is elevated in maternal serum in women with preeclampsia. Whether activin has a role in the pathogenesis of preeclampsia is not known. STUDY DESIGN To assess the effects of activin on endothelial cell function, we cultured human umbilical vein endothelial cells in the presence of activin or serum from normal pregnant women or pregnant women with preeclampsia, with or without follistatin, a functional activin antagonist or apocynin, a NADPH oxidase (Nox2) inhibitor. We also administered activin to pregnant C57Bl6 mice, with or without apocynin, and studied maternal and fetal outcomes. Last, we assessed endothelial cell Nox2 and nitric oxide synthase expression in normal pregnant women and pregnant women with preeclampsia. RESULTS Activin and preeclamptic serum induced endothelial cell oxidative stress by Nox2 up-regulation and endothelial cell dysfunction, which are effects that are mitigated by either follistatin or apocynin. The administration of activin to pregnant mice induced endothelial oxidative stress, hypertension, proteinuria, fetal growth restriction, and preterm littering. Apocynin prevented all of these effects. Compared with normal pregnant women, women with preeclampsia had increased endothelial Nox2 expression. CONCLUSION An activin-Nox2 pathway is a likely link between an injured placenta, endothelial dysfunction, and preeclampsia. This offers opportunities that are not novel therapeutic approaches to preeclampsia.

Future therapies for pre‐eclampsia: beyond treading water

Pre‐eclampsia remains a major burden of disease, accounting for approximately 50,000–70,000 maternal deaths each year worldwide. Frustratingly, the management of pre‐eclampsia has remained essentially unchanged for much of the last century and focussed primarily on maternal blood pressure control to allow fetal maturation. Recent advances in the understanding of the pathogenesis of pre‐eclampsia and the elucidation of distinct underlying mechanisms offer the genuine prospect of new and effective therapies that may transform outcomes for millions of women and their babies.

Melatonin improves endothelial function in vitro and prolongs pregnancy in women with early-onset preeclampsia

Preeclampsia remains a leading cause of maternal and perinatal morbidity and mortality. There have been no material advances in the treatment of preeclampsia for nearly 50 years. Combining in vitro studies and a clinical trial, we aimed to determine whether melatonin could be a useful adjuvant therapy. In a xanthine/xanthine oxidase (X/XO) placental explant model, melatonin reduced oxidative stress (8‐isoprostane) and enhanced antioxidant markers (Nrf2 translocation, HO‐1), but did not affect explant production of anti‐angiogenic factors (sFlt, sEng, activin A). In cultured HUVECs, melatonin mitigated TNFα‐induced vascular cell adhesion molecule expression and rescued the subsequent disruption to endothelial monolayer integrity but did not affect other markers for endothelial activation and dysfunction. In a phase I trial of melatonin in 20 women with preeclampsia, we assessed the safety and efficacy of melatonin on (i) preeclampsia progression, (ii) clinical outcomes, and (iii) oxidative stress, matching outcomes with recent historical controls receiving similar care. Melatonin therapy was safe for mothers and their fetuses. Compared to controls, melatonin administration extended the mean ± SEM diagnosis to delivery interval by 6 ± 2.3 days reduced the need for increasing antihypertensive medication on days 3‐4 (13% vs 71%), days 6‐7 (8% vs 51%), and at delivery (26% vs 75%). All other clinical and biochemical measures of disease severity were unaffected by melatonin. We have shown that melatonin has the potential to mitigate maternal endothelial pro‐oxidant injury and could therefore provide effective adjuvant therapy to extend pregnancy duration to deliver improved clinical outcomes for women with severe preeclampsia.

Embedding assessment in a simulation skills training program for medical and midwifery students: A pre- and post-intervention evaluation

Simulation‐based programs are increasingly being used to teach obstetrics and gynaecology examinations, but it is difficult to establish student learning acquired through them. Assessment may test student learning but its role in learning itself is rarely recognised. We undertook this study to assess medical and midwifery student learning through a simulation program using a pre‐test and post‐test design and also to evaluate use of assessment as a method of learning.

Role of activin A in the pathogenesis of endothelial cell dysfunction in preeclampsia

Circulating markers for endothelial activation such as endothelin-1 (ET-1), ICAM-1 and VCAM-1 are elevated in women with preeclampsia. Using human umbilical vein endothelial cells (HUVECs) as an in vitro model of the maternal vasculature, we show that activin A and preeclamptic serum upregulate ET-1, ICAM-1, and VCAM-1 in HUVECs. Further, we show that follistatin, a specific binding protein for activin, mitigates the upregulation of ET-1, ICAM-1 and VCAM-1 in HUVECs exposed to either activin A or preeclamptic serum. These data are consistent with activin A contributing to the pathophysiology of preeclampsia and suggest that therapies targeting activin signalling are worth exploring.

A Randomized Double-Blinded Placebo-Controlled Intervention Trial of Melatonin for the Prevention of Preeclampsia in Moderate- and High-Risk Women: The MELPOP Trial

This chapter describes the methodologies which may be used in the development of a randomized controlled trial investigating a therapy of choice in preventing preeclampsia.

Phase I Pilot Clinical Trial of Antenatal Maternally Administered Melatonin to Decrease the Level of Oxidative Stress in Human Pregnancies Affected by Preeclampsia

This chapter describes the methodologies which may be used in the development of a phase I clinical trial investigating a therapy of choice in treating preeclampsia.