TY - JOUR
T1 - Sphingosine-1-phosphate-dependent activation of p38 MAPK maintains elevated peripheral resistance in heart failure through increased myogenic vasoconstriction
AU - Hoefer, Judith
AU - Azam, M. Ali
AU - Kroetsch, Jeffrey T E
AU - Poi, Howard Leong
AU - Momen, M. Abdul
AU - Voigtlaender-Bolz, Julia
AU - Scherer, Elias Q.
AU - Meissner, Anja
AU - Bolz, Steffen Sebastian
AU - Husain, Mansoor
PY - 2010/10/1
Y1 - 2010/10/1
N2 - Rationale: Mechanisms underlying vasomotor abnormalities and increased peripheral resistance exacerbating heart failure (HF) are poorly understood. Objective: To explore the role and molecular basis of myogenic responses in HF. Methods and Results: 10 weeks old C57Bl6 mice underwent experimental myocardial infarction (MI) or sham surgery. At 1 to 12 weeks postoperative, mice underwent hemodynamic studies, mesenteric, cerebral, and cremaster artery perfusion myography and Western blot. Organ weights and hemodynamics confirmed HF and increased peripheral resistance after MI. Myogenic responses, ie, pressure-induced vasoconstriction, were increased as early as 1 week after MI and remained elevated. Vasoconstrictor responses to phenylephrine were decreased 1 week after MI, but not at 2 to 6 weeks after MI, whereas those to endothelin (ET)-1 and sphingosine-1-phosphate (S1P) were increased at all time points after MI. An antagonist (JTE-013) for the most abundant S1P receptor detected in mesenteric arteries (S1P2R) abolished the enhanced myogenic responses of HF, with significantly less effect on controls. Mice with genetic absence of sphingosine-kinases or S1P2R (Sphk1-/-; Sphk1 -/-/Sphk2+/-; S1P2R-/-) did not manifest enhanced myogenic responses after MI. Mesenteric arteries from HF mice exhibited increased phosphorylation of myosin light chain, with deactivation of its phosphatase (MLCP). Among known S1P-responsive regulators of MLCP, GTP-Rho levels were unexpectedly reduced in HF, whereas levels of activated p38 MAPK and ERK1/2 (extracellular signal-regulated kinase 1/2) were increased. Inhibiting p38 MAPK abolished the myogenic responses of animals with HF, with little effect on controls. Conclusions: Rho-independent p38 MAPK-mediated deactivation of MLCP underlies S1P/S1P2R-regulated increases in myogenic vasoconstriction observed in HF. Therapeutic targeting of these findings in HF models deserves study.
AB - Rationale: Mechanisms underlying vasomotor abnormalities and increased peripheral resistance exacerbating heart failure (HF) are poorly understood. Objective: To explore the role and molecular basis of myogenic responses in HF. Methods and Results: 10 weeks old C57Bl6 mice underwent experimental myocardial infarction (MI) or sham surgery. At 1 to 12 weeks postoperative, mice underwent hemodynamic studies, mesenteric, cerebral, and cremaster artery perfusion myography and Western blot. Organ weights and hemodynamics confirmed HF and increased peripheral resistance after MI. Myogenic responses, ie, pressure-induced vasoconstriction, were increased as early as 1 week after MI and remained elevated. Vasoconstrictor responses to phenylephrine were decreased 1 week after MI, but not at 2 to 6 weeks after MI, whereas those to endothelin (ET)-1 and sphingosine-1-phosphate (S1P) were increased at all time points after MI. An antagonist (JTE-013) for the most abundant S1P receptor detected in mesenteric arteries (S1P2R) abolished the enhanced myogenic responses of HF, with significantly less effect on controls. Mice with genetic absence of sphingosine-kinases or S1P2R (Sphk1-/-; Sphk1 -/-/Sphk2+/-; S1P2R-/-) did not manifest enhanced myogenic responses after MI. Mesenteric arteries from HF mice exhibited increased phosphorylation of myosin light chain, with deactivation of its phosphatase (MLCP). Among known S1P-responsive regulators of MLCP, GTP-Rho levels were unexpectedly reduced in HF, whereas levels of activated p38 MAPK and ERK1/2 (extracellular signal-regulated kinase 1/2) were increased. Inhibiting p38 MAPK abolished the myogenic responses of animals with HF, with little effect on controls. Conclusions: Rho-independent p38 MAPK-mediated deactivation of MLCP underlies S1P/S1P2R-regulated increases in myogenic vasoconstriction observed in HF. Therapeutic targeting of these findings in HF models deserves study.
KW - heart failure
KW - mitogen-activated protein kinase
KW - myogenic response
KW - sphingosine-1-phosphate
UR - http://www.scopus.com/inward/record.url?scp=77958014002&partnerID=8YFLogxK
U2 - 10.1161/CIRCRESAHA.110.226464
DO - 10.1161/CIRCRESAHA.110.226464
M3 - Article
C2 - 20671234
AN - SCOPUS:77958014002
SN - 0009-7330
VL - 107
SP - 923
EP - 933
JO - Circulation Research
JF - Circulation Research
IS - 7
ER -