Endothelial activation impairs the function of small extracellular vesicles

Abstract

Small extracellular vesicles are nanosized vesicles (30–200 nm) that can ferry proteins, nucleic acids, and lipids between cells and therefore, have significant potential as biomarkers, drug delivery tools or therapeutic agents. SEVs of endothelial origin have been shown to -among other functions-reduce in vitro ischemia/reperfusion (I/R) injury in cardiomyocytes, but whether a pro-inflammatory state of the endothelium impairs the functionality of these SEVs remains to be elucidated. To test this, human umbilical vein endothelial cells cells were treated with TNF-α 10 ng/mL and the expression of the pro-inflammatory parameters VCAM-1, ICAM-1 and eNOS were determined by Western blot. SEVs were isolated from endothelial cells treated with or without TNF-α 10 ng/mL using size exclusion chromatography. The size and concentration of SEVs was measured by Nanoparticle Tracking Analysis. The expression of the surface marker CD81 was determined by immunoassay, whereas their morphology was assessed by electron microscopy. The function of endothelial SEVs was assessed by evaluating their cardioprotective effect in an ex vivo model of global I/R using isolated hearts from adult C57BL/6 mice. Treatment of HUVECs with TNF-α induced the expression of VCAM-1 and ICAM-1, whereas eNOS levels were decreased. TNF-α did not affect the production, size, morphology, or expression of CD81. SEVs significantly reduced the infarct size as compared with untreated mice hearts, but SEVs isolated from TNF-α treated cells were unable to achieve this effect. Therefore, a pro-inflammatory state induced by TNF-α does not alter the production of endothelial SEVs but impairs their function in the setting of I/R injury.

Unraveling the Impact of Extracellular Vesicle-Depleted Serum on Endothelial Cell Characteristics over Time

“…Given that endothelial activation can influence the characteristics of extracellular vesicles [93], we conducted a comprehensive evaluation of these particles. Following the guidelines set by the Minimal Information for Studies of Extracellular Vesicles (MISEV), we characterized the EVs in terms of size, concentration, morphology, and protein content [40,58].…”

Health position paper and redox perspectives on reactive oxygen species as signals and targets of cardioprotection

“…With aging, primary cells undergo senescence, during which they cease proliferation, become pro-inflammatory and produce higher levels of ROS. This increases the production of sEVs [ 567 ]. sEVs from endothelial progenitor cells down-regulated the NOX2/ROS pathway by delivery of miR-18a, thereby protecting them from hypoxia and reoxygenation injury [ 567 ].…”

“…This increases the production of sEVs [ 567 ]. sEVs from endothelial progenitor cells down-regulated the NOX2/ROS pathway by delivery of miR-18a, thereby protecting them from hypoxia and reoxygenation injury [ 567 ]. Interestingly, a population of microvesicles from endothelial cells contained enzymes and substrates of the pentose phosphate pathway leading to their ability to synthesize NADPH, which is a key metabolite in antioxidative pathways.…”

“…Interestingly, a population of microvesicles from endothelial cells contained enzymes and substrates of the pentose phosphate pathway leading to their ability to synthesize NADPH, which is a key metabolite in antioxidative pathways. Thus, they may act as ROS scavengers [ 567 ]. This pathway was even more active in senescent endothelial cells.…”

“…This pathway was even more active in senescent endothelial cells. On the other hand, when human umbilical vein endothelial cells were subject to hypoxia/reoxygenation, the microvesicles they produced induced the phosphorylation of p38 and JNK1/2 and promoted apoptosis and oxidative stress in H9c2 cardiomyocytes [ 567 ].…”