Salsalate negatively impacts microvascular function in women with endometriosis

Women with endometriosis, an inflammatory disease, are at increased risk of cardiovascular disease and demonstrate impaired microvascular endothelial function, characterized by reduced nitric oxide (NO)-mediated vasodilation. In some clinical cohorts, nuclear factor-kappa B (NFκB) inhibition with salsalate improves endothelial function. We hypothesized that salsalate would improve cutaneous microvascular endothelial function in women with endometriosis. Following placebo or salsalate (3,000 mg·day^-1 for 5 days), four intradermal microdialysis probes were placed in 11 women (33 ± 7 yr) with endometriosis. Local heating units (set to 33°C) and laser-Doppler flowmetry (red blood cell flux) probes were placed over the probes. Increasing doses of acetylcholine (ACh; dissolved in lactated Ringer's solution) were perfused, alone (control) or coperfused with: <i>N</i>^G-nitro-l-arginine methyl ester (l-NAME), atorvastatin (statin), or l-NAME + statin (combo). Maximal vasodilation was then induced (local heat at 43°C + sodium nitroprusside perfusion). Data were normalized as percentage of maximal cutaneous vascular conductance (CVC_%max red blood cell flux/mean arterial pressure). To measure macrovascular endothelial function, flow-mediated dilation (FMD) was additionally performed. During placebo, coperfusion with statin did not impact the CVC_%max ACh dose-response (<i>P</i> = 0.93). Oral salsalate attenuated the CVC_%max response to ACh perfusion alone (<i>P</i> < 0.01) but did not impact the l-NAME site (<i>P</i> = 0.09). Salsalate significantly augmented the CVC_%max response of the statin site (<i>P</i> < 0.01) but did not affect the combo site response (<i>P</i> = 1.00). FMD was not different between treatments (<i>P</i> = 0.79). Salsalate treatment impairs vasodilation in the cutaneous microcirculation in women with endometriosis through non-NO-dependent mechanisms.<b>NEW & NOTEWORTHY</b> Our results show that oral salsalate treatment negatively impacts microvascular function but does not alter macrovascular function. In contrast to the majority of other clinical populations with endothelial dysfunction, salsalate treatment reduces microcirculatory function through non-NO-dependent mechanisms in women with endometriosis.