Sex-specific alterations in blood-borne factors in physically inactive individuals are detrimental to endothelial cell functions

Menstrual and oral contraceptive pill cycles minimally influence vascular function and associated cellular regulation in premenopausal females

Historical exclusion of females in research has been, in part, due to the perceived influence of natural menstrual (NAT) and oral contraceptive pill (OCP) cycles on vascular outcomes. NAT and OCP cycle phases may influence brachial artery (BA) endothelial function, however, findings are mixed. Minimal research has examined arterial stiffness, smooth muscle, and lower limb endothelial function. The purpose of this study was to investigate the influence of NAT and OCP cycles on cardiovascular outcomes and cellular regulation. Forty-nine premenopausal females (n = 17 NAT, n = 17 second generation OCP, n = 15 third generation OCP) participated in two randomized order visits in the low (LH, early follicular/placebo) and high (HH, midluteal/active) hormone cycle phases. BA and superficial femoral artery (SFA) endothelial function [flow-mediated dilation (FMD) test], smooth muscle function (nitroglycerine-mediated dilation test), and carotid and peripheral (pulse wave velocity) arterial stiffness were assessed. Cultured female human endothelial cells were exposed to participant serum for 24 h to examine endothelial nitric oxide synthase (eNOS) and estrogen receptor-α (ERα) protein content. BA FMD was elevated in the HH vs. LH phase, regardless of group (HH, 7.7 ± 3.5%; LH, 7.0 ± 3.3%; P = 0.02); however, allometric scaling for baseline diameter resulted in no phase effect (HH, 7.6 ± 2.6%; LH, 7.1 ± 2.6%; P = 0.052, d = 0.35). SFA FMD, BA, and SFA smooth muscle function, arterial stiffness, and eNOS and ERα protein content were unaffected. NAT and OCP phases examined have minimal influence on vascular outcomes and ERα-eNOS pathway, apart from a small effect on BA endothelial function partially explained by differences in baseline artery diameter. NEW & NOTEWORTHY Comprehensive evaluation of the cardiovascular system in naturally cycling and second and third generation OCP users indicates no major influence of hormonal phases examined on endothelial function and smooth muscle function in the arteries of the upper and lower limbs, arterial stiffness, or underlying cellular mechanisms. Study findings challenge the historical exclusion of female participants due to potentially confounding hormonal cycles; researchers are encouraged to consider the hormonal environment in future study design.

Ex Vivo treatment of coronary artery endothelial cells with serum post-exercise training offers limited protection against in vitro exposure to FEC-T chemotherapy

Background: Chemotherapy treatment for breast cancer associates with well-documented cardiovascular detriments. Exercise has shown promise as a potentially protective intervention against cardiac toxicity. However, there is a paucity of evidence for the benefits of exercise on the vasculature. Objectives: This study aimed to determine the effects of chemotherapy on the vascular endothelium; and if there are protective effects of serological alterations elicited by an exercise training intervention. Methods and Results: 15 women participated in a 12-week home-based exercise intervention consisting of three high-intensity interval sessions per week. Human coronary artery endothelial cells (HCAEC) were exposed to physiological concentrations of 5-fluorouracil, epirubicin, cyclophosphamide (FEC) and docetaxel to determine a dose-response. Twenty-4 hours prior to FEC and docetaxel exposure, HCAECs were preconditioned with serum collected pre- and post-training. Annexin V binding and cleaved caspase-3 were assessed using flow cytometry and wound repair by scratch assays. Chemotherapy exposure increased HCAEC Annexin V binding, cleaved caspase-3 expression in a dose-dependent manner; and inhibited wound repair. Compared to pre-training serum, conditioning HCAECs with post-training serum, reduced Annexin V binding (42% vs. 30%, p = 0.01) when exposed to FEC. For docetaxel, there were no within-group differences (pre-vs post-exercise) for Annexin V binding or cleaved caspase-3 expression. There was a protective effect of post-training serum on wound repair for 5-flurouracil (p = 0.03) only. Conclusion: FEC-T chemotherapy drugs cause significant damage and dysfunction of endothelial cells. Preconditioning with serum collected after an exercise training intervention, elicited some protection against the usual toxicity of FEC-T, when compared to control serum.

Circulating MicroRNA Responses to Postprandial Lipemia with or without Prior Exercise

Repeated exposure to a high-fat meal triggers inflammation and oxidative stress, contributing to the onset of cardiometabolic diseases. Regular exercise prevents cardiometabolic diseases and a prior bout of acute endurance exercise can counteract the detrimental cardiovascular effects of a subsequent high-fat meal. Circulating microRNAs (ci-miRs) are potential mediators of these vascular effects through regulation of gene expression at the posttranscriptional level. Therefore, we investigated the expression of ci-miRs related to vascular function (miR-21, miR-92a, miR-126, miR-146a, miR-150, miR-155, miR-181b, miR-221, miR-222) in plasma from healthy, recreationally to highly active, Caucasian adult men after a high-fat meal with (EX) and without (CON) a preceding bout of cycling exercise. Ci-miR-155 was the only ci-miR for which there was a significant interaction effect of high-fat meal and exercise (p=0.050). Ci-miR-155 significantly increased in the CON group at two (p=0.007) and four hours (p=0.010) after the high-fat meal test, whereas it significantly increased in the EX group only four hours after the meal (p=0.0004). There were significant main effects of the high-fat meal on ci-miR-21 (p=0.01), ci-miR-126 (p=0.02), ci-miR-146a (p=0.02), ci-miR-181b (p=0.02), and ci-miR-221 (p=0.008). Collectively, our results suggest that prior exercise does not prevent high-fat meal-induced increases in vascular-related ci-miRs.

The "Hitchhiker's Guide to the Galaxy" of Endothelial Dysfunction Markers in Human Fertility

Endothelial dysfunction is an early event in the pathogenesis of atherosclerosis and represents the first step in the pathogenesis of cardiovascular diseases. The evaluation of endothelial health is fundamental in clinical practice and several direct and indirect markers have been suggested so far to identify any alterations in endothelial homeostasis. Alongside the known endothelial role on vascular health, several pieces of evidence have demonstrated that proper endothelial functioning plays a key role in human fertility and reproduction. Therefore, this state-of-the-art review updates the endothelial health markers discriminating between those available for clinical practice or for research purposes and their application in human fertility. Moreover, new molecules potentially helpful to clarify the link between endothelial and reproductive health are evaluated herein.

Sex differences in the blood-brain barrier and neurodegenerative diseases

The number of people diagnosed with neurodegenerative diseases is on the rise. Many of these diseases, including Alzheimer's disease, Parkinson's disease, multiple sclerosis, and motor neuron disease, demonstrate clear sexual dimorphisms. While sex as a biological variable must now be included in animal studies, sex is rarely included in in vitro models of human neurodegenerative disease. In this Review, we describe these sex-related differences in neurodegenerative diseases and the blood-brain barrier (BBB), whose dysfunction is linked to neurodegenerative disease development and progression. We explain potential mechanisms by which sex and sex hormones affect BBB integrity. Finally, we summarize current in vitro BBB bioengineered models and highlight their potential to study sex differences in BBB integrity and neurodegenerative disease.