Angiotensin-(1-7) ameliorates sepsis-induced cardiomyopathy by alleviating inflammatory response and mitochondrial damage through the NF-κB and MAPK pathways

Background: There is no available viable treatment for Sepsis-Induced Cardiomyopathy (SIC), a common sepsis complication with a higher fatality risk. The septic patients showed an abnormal activation of the renin angiotensin (Ang) aldosterone system (RAAS). However, it is not known how the Ang II and Ang-(1-7) affect SIC. Methods: Peripheral plasma was collected from the Healthy Control (HC) and septic patients and Ang II and Ang-(1-7) protein concentrations were measured. The in vitro and in vivo models of SIC were developed using Lipopolysaccharide (LPS) to preliminarily explore the relationship between the SIC state, Ang II, and Ang-(1-7) levels, along with the protective function of exogenous Ang-(1-7) on SIC. Results: Peripheral plasma Ang II and the Ang II/Ang-(1-7) levels in SIC-affected patients were elevated compared to the levels in HC and non-SIC patients, however, the HC showed higher Ang-(1-7) levels. Furthermore, peripheral plasma Ang II, Ang II/Ang-(1-7), and Ang-(1-7) levels in SIC patients were significantly correlated with the degree of myocardial injury. Additionally, exogenous Ang-(1-7) can attenuate inflammatory response, reduce oxidative stress, maintain mitochondrial dynamics homeostasis, and alleviate mitochondrial structural and functional damage by inhibiting nuclear factor-kappa B (NF-kappa B) and mitogen-activated protein kinase (MAPK) signaling pathways, thus alleviating SIC. Conclusions: Plasma Ang-(1-7), Ang II, and Ang II/Ang-(1-7) levels were regarded as significant SIC biomarkers. In SIC, therapeutic targeting of RAAS, for example with Ang-(1-7), may exert protective roles against myocardial damage.