Connection of reactive oxygen species as an essential actor for the mechanism of phenomena; ischemic preconditioning and postconditioning: Come to age or ripening?

Ischemic preconditioning (IPC), in 1986, and then ischemic postconditioning (IPoC), in 2003, were determined and lots of studies on the many organs were performed about the preventive effects of these strong endogenous mechanisms on the relevant tissues against ischemia-reperfusion and their protective impressions have been emphasized by many authorities up to date. Reactive oxygen molecules are immensely active molecules, originating from molecular oxygen, playing a principal role in intracellular signalization, aging, and various pathologic conditions. Reactive oxygen species (ROS) such as superoxide anion and hydrogen peroxide are known in the pathogenesis of ischemia-reperfusion (I/R) injury. In the pathogenesis of cellular and tissue injury in I/R, the significant output of ROS in the initial phase of reperfusion, particularly between the 1st and 7th min, has been propounded as being an essential and crucial main factor for the phenomena. Even though a great deal of mechanisms has been asserted for IPC and IPoC, the distinct shielder mechanism(s) was/were not clearly proved yet. However, occupying a significant place of ROS among these forecasted mechanisms has been advocated up to date.

Connection of reactive oxygen species as an essential actor for the mechanism of phenomena; ischemic preconditioning and postconditioning: come to age or ripening?

Giriþ: Bindokuzyüzseksenaltý yýlýnda iskemik ön koþullanma (IPC) ve ardýndan 2003 yýlýnda iskemik sonradan koþullanma (IPoC) tanýmlanmýþ ve bu güçlü endojen mekanizmalarýn ilgili dokular üzerinde iskemi-reperfüzyona karþý önleyici etkileri konusunda birçok organ üzerinde çok sayýda çalýþma yapýlmýþ ve koruyucu etkileri, bugüne kadar birçok otorite tarafýndan vurgulanmýþtýr.
Derleme: Reaktif oksijen molekülleri, moleküler oksijenden kaynaklanan, hücre içi sinyalizasyonda, yaþlanmada ve çeþitli patolojik durumlarda temel rol oynayan, son derece aktif moleküllerdir. Süperoksit anyon ve hidrojen peroksit gibi reaktif oksijen türleri (ROT), iskemi-reperfüzyon (I/R) hasarýnýn patogenezinde bilinmektedir. I/R'deki hücresel ve doku hasarýnýn patogenezinde ve reperfüzyonun baþlangýç fazýnda, özellikle birinci ve yedinci dakikalar arasýnda, ROT masif üretimi; bu fenomen için, gerekli ve çok önemli bir ana faktör olarak öne sürülmüþtür.
Sonuç: IPC ve IPoC için çok sayýda mekanizma ileri sürülmüþ olsa da, kesin koruyucu mekanizma(lar) henüz net bir þekilde kanýtlanmamýþtýr. Bununla birlikte; bu öngörülen mekanizmalar arasýnda, ROT'un, önemli bir yer iþgal ettiði savý, günümüze kadar savunulmuþtur. (NCI-2021-1-23)