Macrophage–NLRP3 Inflammasome Activation Exacerbates Cardiac Dysfunction after Ischemic Stroke in a Mouse Model of Diabetes
1 Department of Anesthesiology, Zhujiang Hospital of Southern Medical University, Guangzhou 510220, China
2 Department of Anesthesiology, Shenzhen SAMII Medical Center, Shenzhen 518118, China
3 Department of Anesthesiology, The Second Affiliated Hospital, Shantou University Medical College, Shantou 515041, China
4 University of Ottawa Heart Institute and Department of Cellular and Molecular Medicine, University of Ottawa, Ontario, K1N, Canada
Abstract
Ischemic stroke is one of the leading causes of death worldwide. In the post-stroke stage, cardiac dysfunction is common and is known as the brain–heart interaction. Diabetes mellitus worsens the post-stroke outcome. Stroke-induced systemic inflammation is the major causative factor for the sequential complications, but the mechanism underlying the brain–heart interaction in diabetes has not been clarified. The NLRP3 (NLR pyrin domain-containing 3) inflammasome, an important component of the inflammation after stroke, is mainly activated in M1-polarized macrophages. In this study, we found that the cardiac dysfunction induced by ischemic stroke is more severe in a mouse model of type 2 diabetes. Meanwhile, M1-polarized macrophage infiltration and NLRP3 inflammasome activation increased in the cardiac ventricle after diabetic stroke. Importantly, the NLRP3 inflammasome inhibitor CY-09 restored cardiac function, indicating that the M1-polarized macrophage–NLRP3 inflammasome activation is a pathway underlying the brain–heart interaction after diabetic stroke.
Keywords
Ischemic stroke; Diabetes mellitus; Cardiac dysfunction; NLRP3 inflammasome; Macrophage