title: The novel role of mast cells in the microenvironment of acute myocardial infarction.
abstract: Mast cells are multifunctional cells containing various mediators, such as cytokines, tryptase, and histamine, and they have been identified in infarct myocardium. Here, we elucidated the roles of mast cells in a myocardial infarction (MI) rat model. We studied the physiological and functional roles of mast cell granules (MCGs), isolated from rat peritoneal fluid, on endothelial cells, neonatal cardiomyocytes, and infarct heart (1-hour occlusion of left coronary artery followed by reperfusion). The number of mast cells had two peak time points of appearance in the infarct region at 1day and 21days after MI induction in rats (p<0.05 in each compared with sham-operated heart). Simultaneous injection of an optimal dose of MCGs modulated the microenvironment and resulted in the increased infiltration of macrophages and decreased apoptosis of cardiomyocytes without change in the mast cell number in infarct myocardium. Moreover, MCG injection attenuated the progression of MI through angiogenesis and preserved left ventricular function after MI. MCG-treated cardiomyocytes were more resistant to hypoxic injury through phosphorylation of Akt, and MCG-treated endothelial cells showed enhanced migration and tube formation. We have shown that MCGs have novel cardioprotective roles in MI via the prolonged survival of cardiomyocytes and the induction of angiogenesis.
authors.affiliation: Stem Cell Research Center of Chonnam National University Hospital, Gwangju, Republic of Korea.
authors.forename: Jin Sook
authors.initials: JS
authors.lastname: Kwon
authors.forename: Yong Sook
authors.initials: YS
authors.lastname: Kim
authors.forename: Ae Shin
authors.initials: AS
authors.lastname: Cho
authors.forename: Hyang Hee
authors.initials: HH
authors.lastname: Cho
authors.forename: Jeong Sook
authors.initials: JS
authors.lastname: Kim
authors.forename: Moon Hwa
authors.initials: MH
authors.lastname: Hong
authors.forename: Seo Yeon
authors.initials: SY
authors.lastname: Jeong
authors.forename: Myung Ho
authors.initials: MH
authors.lastname: Jeong
authors.forename: Jeong Gwan
authors.initials: JG
authors.lastname: Cho
authors.forename: Jong Chun
authors.initials: JC
authors.lastname: Park
authors.forename: Jung Chaee
authors.initials: JC
authors.lastname: Kang
authors.forename: Youngkeun
authors.initials: Y
authors.lastname: Ahn
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000502:physiology; D015153:Blotting, Western; D015687:Cell Hypoxia / Q000502:physiology; D002478:Cells, Cultured; D003594:Cytoplasmic Granules / Q000378:metabolism*; D006439:Hemodynamics; D006801:Humans; D008297:Male; D008407:Mast Cells / Q000378:metabolism* / Q000502:physiology; D009203:Myocardial Infarction / Q000378:metabolism* / Q000473:pathology; D009206:Myocardium / Q000378:metabolism / Q000473:pathology; D051381:Rats; D017207:Rats, Sprague-Dawley; D020133:Reverse Transcriptase Polymerase Chain Reaction