Catestatin reduces myocardial ischaemia/reperfusion injury: involvement of PI3K/Akt, PKCs, mitochondrial KATP channels and ROS signalling

Abstract

Aims: Catestatin (CST) limits myocardial ischaemia/reperfusion (I/R) injury with unknown mechanisms. Clearly phosphoinositide-3-kinase (PI3K), protein-kinase-C (PKC) isoforms, including intra-mitochondrial PKCε, mitochondrial-K ATP (mitoK ATP ) channels and subsequent reactiveoxygen-species (ROS)-signalling play important roles in postconditioning cardioprotection, preventing mitochondrial permeability transition pore (mPTP) opening. Therefore, we studied the role of these extra-and intra-mitochondrial factors in CST-induced protection. Methods and Results: Isolated rat hearts and H9c2 cells underwent I/R and oxidative stress, respectively. In isolated hearts CST (75nM, CST-Post) given in early-reperfusion significantly reduced infarct-size, limited post-ischaemic contracture, and improved recovery of developed left ventricular pressure.PI3K inhibitor, LY-294002 (LY), large spectrum PKC inhibitor, Chelerythrine (CHE), specific PKCε inhibitor (εV1-2), mitoK ATP channel blocker, 5-Hydroxydecanoate (5HD) or ROS scavenger, 2-mercaptopropionylglycine (MPG) abolished the infarct-sparing effect of CST. Notably the CSTinduced contracture limitation was maintained during co-infusion of 5HD, MPG or εV1-2, but it was lost during co-infusion of LY or CHE. In H9c2 cells challenged with H 2 O 2 , mitochondrialdepolarization (an index of mPTP-opening studied with JC1-probe) was drastically limited by CST (75nM). Conclusions: Our results suggest that the protective signalling pathway activated by CST includes mitoK ATP channels, ROS-signalling and prevention of mPTP opening, with a central role for upstream PI3K/Akt and PKCs. In fact, all inhibitors completely abolished CST-infarct-sparing effect. Since CST-anti-contracture effect cannot be explained by intra-mitochondrial mechanisms (PKCε activation and mitoK ATP channel opening) or ROS-signalling, it is proposed that these downstream signals are part of a reverberant loop which re-activates upstream PKCs, which therefore play a pivotal role in CST-induced protection.

Obestatin regulates cardiovascular function and promotes cardioprotection through the nitric oxide pathway

“…of stabilization and the first 20 min. of reperfusion at the concentrations described previously 33, 34, 38. These concentrations of the inhibitors did not affect basal cardiac performance, as demonstrated by our preliminary results.…”

Kobophenol A Inhibits Sodium Nitroprusside-Induced Cardiac H9c2 Cell Death through Suppressing Activation of JNK and Preserving Mitochondrial Anti-apoptotic Bcl-2 and Mcl-1

“…To exclude the potential involvement of NO and to find the direct cellular damaging moiety caused by SNP in H9c2 cells, the effects of deferoxamine (DFO; an iron chelating agent, 50 µM), 16) 2-mercaptopropionylglycine (2-MPG; a reactive oxygen species (ROS) scavenger, 300 µM), 17) (PTIO; a NO scavenger, 100 µM), 18) resveratrol (phytoestrogen with ROS scavenging activity, 50 µM) 19) on SNP-triggered H9c2 cells death were tested (Fig. 5).…”

Nanoprecipitated catestatin released from pharmacologically active microcarriers (PAMs) exerts pro-survival effects on MSC

“…As demonstrated by us and other authors, CST is a very promising agent for a cardiovascular protective purpose (Bassino et al, 2011;Bassino et al, 2015;Egger et al, 2008;Penna et al, 2010;Perrelli et al, 2013). In order to reduce damage observed in cardiovascular system following oxidative stress and prolonged hypoxic conditions, therapies with cell 440 transplantation could represent a good strategy to follow; however approaches adapted to the varying conditions are needed.…”

“…Moreover a myocardial production of CST was demonstrated recently (Bassino et al, 2011;Bassino et al, 2015;Biswas et al, 2010;Penna et al, 2010;Penna et al, 2012;Perrelli et al, 2013). The anti-adrenergic effects of CST in the heart muscle seem to be mediated by 65 the PI3K-Akt-eNO-Synthase signaling axis (Bassino et al, 2011;Bassino et al, 2015).…”