Sparstolonin B attenuates hypoxia-reoxygenation-induced cardiomyocyte inflammation.
Myocardial ischemia-reperfusion (MIR) injury is characterized by a rapid increase in cytokines and chemokines and an infiltration of inflammatory cells. Toll-like receptors (TLRs) 2 and 4 mediate these inflammatory responses. Herein we investigated the ability of Sparstolonin B (SsnB), a new selective TLR2/4 antagonist, to inhibit the TLR2/4-mediated inflammatory responses during cardiomyocyte hypoxia-reoxygenation injury as well as the responsible mechanisms. Lactate dehydrogenase (LDH) assay was performed to measure the cytotoxicity of SsnB on H9c2 cardiomyocytes. Quantitative real-time PCR (qRT-PCR) confirmed that TLR2 and TLR4 expression was elevated during hypoxia-reoxygenation, and that their up-regulation in cardiomyocytes was significantly inhibited by SsnB (P < 0.05). Both the mRNA and protein levels of monocyte chemotactic protein-1 and high mobility group box 1 were up-regulated during hypoxia-reoxygenation and were significantly attenuated by SsnB (P < 0.05). Next we found that extracellular signal-regulated kinase 1 or 2 (ERK1/2) and c-Jun NH2-terminal kinase (JNK) signaling pathways were activated during hypoxia-reoxygenation and SsnB significantly inhibited their activation (P < 0.05). Moreover, transwell migration assays revealed that the migration of mouse macrophages to hypoxia-reoxygenation injured cardiomyocytes was significantly reduced by SsnB (P < 0.05). In conclusion, our data indicate that the new selective TLR2 and TLR4 antagonist, SsnB, can substantially attenuate hypoxia-reoxygenation-induced inflammation of cardiomyocytes via inhibiting ERK1/2 and JNK signaling pathways. Accordingly, SsnB has the potential to serve as a therapeutic agent for the prevention of MIR injury.
Department of Cell Biology and Anatomy, University of South Carolina School of Medicine, Columbia, SC 29209, USA.
Qing
Q
Liu
Junfeng
J
Wang
Qiaoli
Q
Liang
Dawei
D
Wang
Yi
Y
Luo
Jianping
J
Li
Joseph S
JS
Janicki
Daping
D
Fan
D000818:Animals; D015687:Cell Hypoxia / Q000187:drug effects; D002460:Cell Line; D002465:Cell Movement / Q000187:drug effects; D018932:Chemokine CCL2 / Q000235:genetics / Q000378:metabolism; D004365:Drugs, Chinese Herbal / Q000494:pharmacology; D004789:Enzyme Activation; D048049:Extracellular Signal-Regulated MAP Kinases / Q000378:metabolism; D024243:HMGB1 Protein / Q000235:genetics / Q000378:metabolism; D006576:Heterocyclic Compounds, 4 or More Rings / Q000494:pharmacology*; D007249:Inflammation / Q000188:drug therapy; D048031:JNK Mitogen-Activated Protein Kinases / Q000378:metabolism; D020935:MAP Kinase Signaling System; D008264:Macrophages / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D009203:Myocardial Infarction / Q000188:drug therapy / Q000378:metabolism; D015428:Myocardial Reperfusion Injury / Q000188:drug therapy* / Q000378:metabolism; D032383:Myocytes, Cardiac / Q000187:drug effects / Q000276:immunology / Q000378:metabolism; D012333:RNA, Messenger / Q000096:biosynthesis; D051381:Rats; D051195:Toll-Like Receptor 2 / Q000037:antagonists & inhibitors*; D051197:Toll-Like Receptor 4 / Q000037:antagonists & inhibitors*
C491766:Ccl2 protein, rat; D018932:Chemokine CCL2; D004365:Drugs, Chinese Herbal; D024243:HMGB1 Protein; D006576:Heterocyclic Compounds, 4 or More Rings; D012333:RNA, Messenger; C495343:Tlr2 protein, rat; C495347:Tlr4 protein, rat; D051195:Toll-Like Receptor 2; D051197:Toll-Like Receptor 4; C561322:sparstolonin B; D048049:Extracellular Signal-Regulated MAP Kinases; D048031:JNK Mitogen-Activated Protein Kinases
Myocardial ischemia–reperfusion injury; Sparstolonin B; Toll-like receptor; inflammation; macrophage