PAI-1, tPA, TFPI and Endometrial Endothelial Cells in Uterine Hemostasis

PROJECT SUMMARY/ABSTRACT Up to 30% of menstruating individuals experience heavy menstrual bleeding (HMB) at some point. HMB is associated with complications such as iron deficiency anemia and increased requirements for medical and surgical interventions, as well as decreased quality of life and missed work or school. While HMB is associated with structural anomalies such as fibroids, bleeding disorders and anticoagulation, in many cases there is no known cause. Prior studies have demonstrated a positive association between increased tissue plasminogen activator (tPA), an anticoagulant factor, and plasminogen activator inhibitor-1 (PAI-1), a procoagulant factor, and HMB. Such factors, along with other important pro- and anticoagulant factors, such as von Willebrand factor (VWF) and tissue factor pathway inhibitor (TFPI) are expressed by endothelial cells. We hypothesize that endometrial endothelial cells (EECs) regulate uterine hemostasis through the up and down regulation of coagulation factors and that differences in such factors contribute to HMB. We propose to investigate the role of tPA, PAI-1, TFPI, VWF multimers and EECs in uterine hemostasis through (1) quantification of tPA, PAI-1 and TFPI in the menstrual blood of women with and without HMB on each day of menstrual bleeding, (2) comparative analysis of VW multimer distribution in the same samples and (3) single cell RNA sequencing of endometrial biopsy samples, including EECs, with attention to coagulation factors. The results of this study will be used to generate testable hypotheses regarding management options for HMB. Dr. Samuelson Bannow has generated data supporting the important contribution of coagulation factors to differences in menstrual bleeding by demonstrating increased risk of HMB in women who use oral anticoagulants associated with higher peaks of activated anti-factor X effect compared to those with lower peak effect. Her primary mentor, Dr. Alison Edelman, has extensive experience with clinical and translational studies of menstrual bleeding and her co-mentor, Dr. Les Myatt, has expertise in women's health and basic science techniques such as cell culture and RNA sequencing. Her advisors will provide additional expertise and guidance in interpretation of RNAseq data and biostatistics. The proposed training will enable Dr. Samuelson Bannow to acquire clinical and research expertise in women's health, gain experience with translational and basic scientific research methods, and develop skills in granstmanship and scientific communication. Importantly it will also allow her to develop the necessary research infrastructure and program for future, independently funded studies in the pathophysiology and management of excessive uterine bleeding.