title: Mechanical stretch activates the JAK/STAT pathway in rat cardiomyocytes.
abstract: This study was designed to determine whether mechanical stretch activates the Janus kinase (JAK)/signal transducers and activators of transcription (STAT) pathway in cardiomyocytes and, if so, by what mechanism. Neonatal rat/murine cardiomyocytes were cultured on malleable silicone dishes and were stretched by 20%. Mechanical stretch induced rapid phosphorylation of JAK1, JAK2, Tyk2, STAT1, STAT3, and glycoprotein 130 as early as 2 minutes and peaked at 5 to 15 minutes. It also caused gel mobility shift of sis-inducing element, which was supershifted by preincubation with anti-STAT3 antibody. Preincubation with CV11974 (AT1 blocker) partially inhibited the phosphorylation of STAT1, but not that of STAT3. Preincubation with TAK044 (endothelin-1-type A/B-receptor blocker) did not attenuate this pathway. RX435 (anti-glycoprotein 130 blocking antibody) inhibited the phosphorylation of STAT3 and partially inhibited that of STAT1. Phosphorylation of STAT1 and STAT3 was strongly inhibited by HOE642 (Na+/H+ exchanger inhibitor) and BAPTA-AM (intracellular calcium chelator), but not by gadolinium (stretch-activated ion channel inhibitor), EGTA (extracellular Ca2+ chelator), or KN62 (Ca2+/calmodulin kinase II inhibitor). Chelerythrine (protein kinase C inhibitor) partially inhibited the phosphorylation of STAT1 and STAT3. Mechanical stretch also augmented the mRNA expression of cardiotrophin-1, interleukin-6, and leukemia inhibitory factor at 60 to 120 minutes. These results indicated that the JAK/STAT pathway was activated by mechanical stretch, and that this activation was partially dependent on autocrine/paracrine-secreted angiotensin II and was mainly dependent on the interleukin-6 family of cytokines but was independent of endothelin-1. Moreover, certain levels of intracellular Ca2+ were necessary for stretch-induced activation of this pathway, and protein kinase C was also partially involved in this activation.
authors.affiliation: Department of Internal Medicine, Keio University, Tokyo, Japan.
authors.forename: J
authors.initials: J
authors.lastname: Pan
authors.forename: K
authors.initials: K
authors.lastname: Fukuda
authors.forename: M
authors.initials: M
authors.lastname: Saito
authors.forename: J
authors.initials: J
authors.lastname: Matsuzaki
authors.forename: H
authors.initials: H
authors.lastname: Kodama
authors.forename: M
authors.initials: M
authors.lastname: Sano
authors.forename: T
authors.initials: T
authors.lastname: Takahashi
authors.forename: T
authors.initials: T
authors.lastname: Kato
authors.forename: S
authors.initials: S
authors.lastname: Ogawa
mesh_terms: D000804:Angiotensin II / Q000378:metabolism; D000818:Animals; D015703:Antigens, CD / Q000378:metabolism; D019898:Autocrine Communication / Q000502:physiology; D002118:Calcium / Q000378:metabolism; D002273:Carcinogens / Q000494:pharmacology; D006332:Cardiomegaly / Q000378:metabolism; D002478:Cells, Cultured; D050822:Cytokine Receptor gp130; D004268:DNA-Binding Proteins / Q000378:metabolism*; D019332:Endothelin-1 / Q000378:metabolism; D015971:Gene Expression Regulation, Enzymologic; D015850:Interleukin-6 / Q000235:genetics; D053613:Janus Kinase 1; D053614:Janus Kinase 2; D008562:Membrane Glycoproteins / Q000378:metabolism; D051379:Mice; D008813:Mice, Inbred ICR; D018485:Muscle Fibers, Skeletal / Q000166:cytology / Q000187:drug effects / Q000201:enzymology*; D009200:Myocardial Contraction / Q000502:physiology*; D009206:Myocardium / Q000166:cytology / Q000201:enzymology*; D019899:Paracrine Communication / Q000502:physiology; D010766:Phosphorylation; D011493:Protein Kinase C / Q000378:metabolism; D011505:Protein-Tyrosine Kinases / Q000378:metabolism*; D011506:Proteins / Q000378:metabolism; D011518:Proto-Oncogene Proteins; D051381:Rats; D017208:Rats, Wistar; D050794:STAT1 Transcription Factor; D050796:STAT3 Transcription Factor; D015398:Signal Transduction / Q000502:physiology; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism; D013314:Stress, Mechanical; D053634:TYK2 Kinase; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology; D015534:Trans-Activators / Q000378:metabolism*
chemical_list: D015703:Antigens, CD; D002273:Carcinogens; D004268:DNA-Binding Proteins; D019332:Endothelin-1; C494200:Il6st protein, mouse; C494201:Il6st protein, rat; D015850:Interleukin-6; D008562:Membrane Glycoproteins; D011506:Proteins; D011518:Proto-Oncogene Proteins; D050794:STAT1 Transcription Factor; D050796:STAT3 Transcription Factor; C494080:Stat1 protein, mouse; C494081:Stat1 protein, rat; C494087:Stat3 protein, mouse; C494088:Stat3 protein, rat; D015534:Trans-Activators; D000804:Angiotensin II; D050822:Cytokine Receptor gp130; D011505:Protein-Tyrosine Kinases; C507905:Jak1 protein, mouse; C507906:Jak1 protein, rat; C507926:Jak2 protein, mouse; C507927:Jak2 protein, rat; D053613:Janus Kinase 1; D053614:Janus Kinase 2; D053634:TYK2 Kinase; C499356:Tyk2 protein, mouse; C499357:Tyk2 protein, rat; D011493:Protein Kinase C; D000254:Sodium-Potassium-Exchanging ATPase; D013755:Tetradecanoylphorbol Acetate; D002118:Calcium