Extracellular vesicles isolated from patients undergoing remote ischemic preconditioning decrease hypoxia-evoked apoptosis of cardiomyoblasts after isoflurane but not propofol exposure

Abstract

Remote ischemic preconditioning (RIPC) can evoke cardioprotection following ischemia/ reperfusion and this may depend on the anesthetic used. We tested whether 1) extracellular vesicles (EVs) isolated from humans undergoing RIPC protect cardiomyoblasts against hypoxia-induced apoptosis and 2) this effect is altered by cardiomyoblast exposure to isoflurane or propofol. EVs were isolated before and 60 min after RIPC or Sham from ten patients undergoing coronary artery bypass graft surgery with isoflurane anesthesia and quantified by Nanoparticle Tracking Analysis. Following EV-treatment for 6 hours under exposure of isoflurane or propofol, rat H9c2 cardiomyoblasts were cultured for 18 hours in normoxic or hypoxic atmospheres. Apoptosis was detected by flow cytometry. Serum nanoparticle concentrations in patients had increased sixty minutes after RIPC compared to Sham (2.5x10 11 ±4.9x10 10 nanoparticles/ml; Sham: 1.2x10 11 ±2.0x10 10 ; p = 0.04). Hypoxia increased apoptosis of H9c2 cells (hypoxia: 8.4%±0.6; normoxia: 2.5%±0.1; p<0.0001). RIPC-EVs decreased H9c2 cell apoptosis compared to control (apoptotic ratio: 0.83; p = 0.0429) while Sham-EVs showed no protection (apoptotic ratio: 0.97). Prior isoflurane exposure in vitro even increased protection (RIPC-EVs/control, apoptotic ratio: 0.79; p = 0.0035; Sham-EVs/control, apoptotic ratio:1.04) while propofol (50μM) abrogated protection by RIPC-EVs (RIPC-EVs/control, Apoptotic ratio: 1.01; Sham-EVs/control, apoptotic ratio: 0.94; p = 0.602). Thus, EVs isolated from patients undergoing RIPC under isoflurane anesthesia protect H9c2 cardiomyoblasts against hypoxia-evoked apoptosis and this effect is

Remote Ischemic Preconditioning Improves Tissue Oxygenation in a Porcine Model of Controlled Hemorrhage Without Fluid Resuscitation

“…However, it was suggested that RIPC increases endogenous plasma exosomes or microvesicles (possibly platelet-derived) [34] that can deliver signals to the myocardium and other tissues to provide protection against ischemia and reperfusion injury by a pathway involving TLR4 and protective heat shock proteins [34][35][36][37]. Of interest, Abel et al reported that extracellular microvesicles isolated from patients undergoing RIPC vs sham were associated with decreased hypoxia-evoked apoptosis of cardiomyoblasts after iso urane --but not propofol exposure [15,38]. Yu et al [39], in a rodent model, suggested that propofol blunts the cardioprotective effect of RIPC through its effect on the cardiac TRPV1 channel only if it is administered before RIPC, but not when propofol is given after RIPC [40].…”

Remote ischemic preconditioning improves tissue oxygenation in a porcine model of controlled hemorrhage without fluid resuscitation

“…However, it was suggested that RIPC increases endogenous plasma exosomes or microvesicles (possibly platelet-derived) 34 that can deliver signals to the myocardium and other tissues to provide protection against ischemia and reperfusion injury by a pathway involving TLR4 and protective heat shock proteins 34 – 37 . Of interest, Abel et al reported that extracellular microvesicles isolated from patients undergoing RIPC versus sham were associated with decreased hypoxia-evoked apoptosis of cardiomyoblasts after isoflurane – but not after propofol 15 , 38 . Yu et al 39 , in a rodent model, suggested that propofol blunts the cardioprotective effect of RIPC through its effect on the cardiac TRPV1 channel only if it is administered before RIPC, but not when propofol is given after RIPC 40 .…”

A Simple and Quick Method for Loading Proteins in Extracellular Vesicles

“…However, genetic engineering approaches, which can be expensive and time-consuming, can only be used with EVs obtained from cell culture. It is necessary to use other methods to load therapeutic agents into EVs obtained directly from human plasma [ 41 , 42 , 43 , 44 ], adipose tissue [ 45 , 46 , 47 ], and breast milk [ 48 , 49 , 50 ]. Additionally, it may be challenging or impossible to implement genetic engineering approaches for EVs obtained from plants [ 51 , 52 ] and animal sources, such as bovine milk [ 53 , 54 , 55 , 56 , 57 ].…”