Open AccessReceptor Mas Protects Mice Against Hypothermia and Mortality Induced By Endotoxemia
Author(s) -
Laura L. Souza,
Johan Duchêne,
Mihail Todiras,
Luciano César Pontes Azevedo,
Cláudio M. Costa-Neto,
Natalia Alenina,
Robson A.S. Santos,
Michael Bäder
Publication year - 2014
Publication title -
shock
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.095
H-Index - 117
eISSN - 1540-0514
pISSN - 1073-2322
DOI - 10.1097/shk.0000000000000115
Subject(s) - proinflammatory cytokine , angiotensin ii , lipopolysaccharide , hypothermia , endocrinology , renin–angiotensin system , medicine , receptor , cytokine , tumor necrosis factor alpha , in vivo , angiotensin ii receptor type 1 , chemistry , pharmacology , homeostasis , inflammation , biology , blood pressure , microbiology and biotechnology
The renin-angiotensin (Ang) system is involved in maintaining cardiovascular function by regulating blood pressure and electrolyte homeostasis. More recently, alternative pathways within the renin-angiotensin system have been described, such as the ACE-2/Ang-(1-7)/Mas axis, with opposite effects to the ones of the ACE/Ang-II/AT1 axis. Correspondingly, our previous work reported that Ang-(1-7) via its receptor Mas inhibits the mRNA expression of the proinflammatory cytokines interleukin 6 (IL-6) and tumor necrosis factor-α increased by lipopolysaccharide (LPS) in mouse peritoneal macrophages. These data led us to investigate the functional role of the Ang-(1-7)/Mas axis in an in vivo LPS model. In this work, we present evidence that Ang-(1-7) via Mas significantly reduced the LPS-increased production of circulating cytokines, such as IL-6, IL-12, and CXCL-1. This inhibitory effect was mediated by Mas because it was not detectable in Mas-deficient (Mas) mice. Accordingly, IL-6, CXCL-1, and CXCL-2 levels were higher after LPS treatment in the absence of Mas. Mas mice were less resistant to LPS-induced endotoxemia, their survival rate being 50% compared with 95% in wild-type mice. Telemetric analyses showed that Mas mice presented more pronounced LPS-induced hypothermia with a 3°C lower body temperature compared with wild-type mice. Altogether, our findings suggest that Ang-(1-7) and Mas inhibit LPS-induced cytokine production and hypothermia and thereby protect mice from the fatal consequences of endotoxemia.