Angiotensins and Their Receptors in Cardiac and Vascular Injury

The renin-angiotensin system is involved in hypertension and, thus, in cardiac and vascular injury. In general, angiotensin II is considered as the main mediator of this system but angiotensin IIderived peptides were also shown to exert effects in such diseases. Moreover, it became obvious that different cell and corresponding tissue types are characterized by their own renin-angiotensin system. This system is composed of various peptidic derivatives of the precursor angiotensinogen. Those angiotensinogen-derived peptides can be processed further by peptidases and can bind corresponding receptors. Various clinical trials were initiated considering inhibition of the renin-angiotensin system at different stages in cardiac injuries. Recently, a phase 3 trial using infused angiotensin II (LJPC-501) as treatment option in catecholamine-resistent hypotension was established (ClinicalTrials.gov identifier NCT02338843) although it might be that an influence of AngII-derived peptides is not considered. In general, more intense research on AngII-derived peptides should result in novel strategies and therapeutic options in treatment of cardiac and vascular injuries since these peptides exert actions by themselves, some may interfere with AngII-mediated effects, and some can bind different receptors as well. Consequently, they may also become new promising therapeutics in clinical settings in the future. This short review introduces all currently known angiotensins at once, their production and role related to cardiac and vascular injury, which immune cells show renin-angiotensin system components, and how immune cells containing such components might be involved in such diseases as well.