Endometriosis and Microvascular Dysfunction: Role of Inflammation

Overview

The purpose of this study is to better understand the underlying mechanisms associated with elevated cardiovascular disease risk in women with endometriosis, and to measure the effectiveness of emerging endometriosis treatments on outcomes specific to cardiovascular dysfunction. Epidemiologic data demonstrate a clear association between endometriosis, reproductive risk factors, inflammation and cardiovascular (CV) risk. Circulating factors, low-density lipoprotein (LDL) and oxidized LDL (oxLDL), are two of many biomarkers of cardiovascular and inflammatory disease of endometriosis. An important signaling mechanism through which circulating LDL and oxLDL act is the lectin-like oxidized LDL receptor (LOX-1). LOX-1 signal transduction functionally results in pronounced endothelial dysfunction, a hallmark of CV. The investigators hypothesis that one factor mediating the elevated risk of cardiovascular disease in endometriosis is systemic inflammation and activation of LOX-1 receptor mechanisms.

Endometriosis is an estrogen-dependent gynecological disorder associated with considerable chronic pelvic pain, pain during intercourse, and is a major cause of infertility. This disorder affects 6% - 10% of reproductive age women and can be as high as 35-50% in women experiencing pain or infertility. Endometriosis derives from the presence of endometrium-like tissue in sites outside the uterine cavity. While endometriosis is a local inflammatory syndrome, the inflammatory process is systemic. Endometriosis is associated with higher risk of hypercholesterolemia and hypertension 8. Epidemiologic data demonstrate a clear association between endometriosis, reproductive risk factors, inflammation and cardiovascular (CV) risk. Endometriosis a disease of inflammation and increased systemic inflammatory cytokine production, although the precise mechanisms by which localized lesion results in systemic inflammation are incompletely understood. Published data confirm an elevation of several inflammatory cytokines in the circulation of women with endometriosis. Alterations in circulating miRNAs specific to endometriosis are one mechanism causing immune dysfunction and subsequent increased cytokine expression in areas remote from the endometriotic lesions. This aberrant increase in systemic cytokine production is a highly plausible putative link to accelerated vascular dysfunction and atherosclerosis in women with endometriosis. The circulating factors LDL and oxidized LDL are two of the many biomarkers of cardiovascular and inflammatory disease of endometriosis. An important signaling mechanism through which circulating LDL and oxLDL act is the lectin-like oxidized LDL receptor (LOX-1). LOX-1 is a ubiquitously expressed scavenger receptor, stimulated by oxLDL, Ang II, and other inflammatory cytokines, and inhibited by estrogen. LOX-1 is the upstream signaling initiator of mechanisms including increased oxidant production, reduced nitric oxide (NO) metabolism, and impaired intracellular trafficking. Thus, LOX-1 signal transduction functionally results in pronounced endothelial dysfunction.