H IKKi influences cardiomyocyte growth. Furthermore, we demonstrated that IKKi overexpression

H IKKi influences cardiomyocyte growth. Furthermore, we demonstrated that IKKi overexpression markedly inhibited AKT and NF-kB signaling in cultured cardiomyocytes stimulated by Ang II.However, the mechanism by which IKKi specifically activates AKT signaling remains unknown. In accordance with our findings, TRAF-associated NFkB activator-binding kinase1 (TBK1), another IkB kinase-related kinase, which exhibits 49 identity and 65 similarity to IKKi, another member of the IKK family, has been shown to control the activation of AKT [34,35]. As a ligand for integrins, the absence of IKKi may be compensated for by TBK1,thus modulating integrin signaling or a specific integrin complex in a manner that specifically regulates AKT. Further experiments are needed to determine the molecular signaling mechanism by which IKKi regulates AKT. It is worth noting that the AKT pathway is a non-specificIKKi Deficiency Promotes Cardiac HypertrophyTable 2. Anatomic and hemodynamic parameters in IKKi KO and WT mice at 4 weeks after surgery.ParameterSham WT(n = 6) IKKi KO(n = 6) 27.1960.32 4.4360.04 4.9060.10 6.5160.08 462610 117.1564.04 10.2461.28 10.5161.46 24.8561.83 10663.836781.97 28967.336357.21 64.0262.AB WT(n = 6) 27.8960.34 6.4960.08* 5.1960.13 9.9660.08* 47768 150.8562.16* 17.7562.14* 23.5861.93* 34.4461.32* 8171.176326.82* 27658.176346.37* 39.1862.40* IKKi KO(n = 6) 28.0260.40 8.5360.42*# 26001275 9.3360.76*# 12.8360.48*# 462618 149.2562.30* 24.3161.84*# 37.2363.46*# 48.3763.29*# 6694.336306.38*# 26578.AVP 176416.63*# 25.8363.11*#BW (g) HW/BW(mg/g) LW/BW(mg/g) HW/TL(mg/cm) HR (beats/min) ESP (mmHg) EDP (mmHg) ESV (ml) EDV (ml) dP/dt max (mmHg/s) dP/dt min (mmHg/s) EF( )27.5060.52 4.2960.07 5.2060.05 6.4060.13 48369 105.7461.58 9.8460.19 10.0960.44 26.8260.78 10585.476540.98 29177.346269.63 65.6061.BW,body weight;HW/BW,heart weight/body weight;LW/BW,lung weight/body weight; HW/TL,heart weight/tibial length; HR,heart rate; ESP, end-systolic pressure; EDP, end-diastolic pressure; ESV, endsystolic volume; EDV, end-diastolic volume; EF, ejection fraction; dP/dtmax, maximal rate of pressure development; dP/dtmin, maximal rate of pressure decay. *P,0.05 vs WT/sham; # P,0.05 vs WT/AB after AB. doi:10.1371/journal.pone.0053412.tFigure 3. IKKi overexpression attenuates myocyte hypertrophy in vitro. A, The inhibitory effect of IKKi overexpression on the enlargement of myocyte induced by Ang II (1 mM for 48 h). B, HIF-2��-IN-1 RT-PCR analysis of the mRNA levels of ANP and BNP induced by Ang II at the time points indicated. * P,0.05 vs WT at the 0 time point. # P,0.05 vs WT at the same time point. doi:10.1371/journal.pone.0053412.gIKKi Deficiency Promotes Cardiac HypertrophyFigure 4. Effect of IKKi on the MAPK and AKT/GSK3b/mTOR/FOXO/NFkB signaling pathways. (A ) Levels of total and phosphorylated MEK1/2, ERK1/2, JNK, P38PI3K, AKT, GSK3b, mTOR, FOXO and NFkB in the heart tissues of mice in the indicated groups (n = 6). A and C Representative blots. B and D Quantitative results. (E ) Representative blots for total and phosphorylated AKT, GSK3b, mTOR, FOXO3A, FOXO1 and NFkB after treatment with Ang II for the indicated times in H9c2 rat cardiomyocytes infected with Ad-GFP or Ad-IKKi. E Representative blots. F, Quantitative results. *P,0.05 vs. WT/sham; # P,0.05 vs. WT/AB after AB. doi:10.1371/journal.pone.0053412.gpathways, and a change in the AKT pathway is likely to be an indicator rather than a true determinant and a pharmacological target.Fibrosis is an important contributor to the.H IKKi influences cardiomyocyte growth. Furthermore, we demonstrated that IKKi overexpression markedly inhibited AKT and NF-kB signaling in cultured cardiomyocytes stimulated by Ang II.However, the mechanism by which IKKi specifically activates AKT signaling remains unknown. In accordance with our findings, TRAF-associated NFkB activator-binding kinase1 (TBK1), another IkB kinase-related kinase, which exhibits 49 identity and 65 similarity to IKKi, another member of the IKK family, has been shown to control the activation of AKT [34,35]. As a ligand for integrins, the absence of IKKi may be compensated for by TBK1,thus modulating integrin signaling or a specific integrin complex in a manner that specifically regulates AKT. Further experiments are needed to determine the molecular signaling mechanism by which IKKi regulates AKT. It is worth noting that the AKT pathway is a non-specificIKKi Deficiency Promotes Cardiac HypertrophyTable 2. Anatomic and hemodynamic parameters in IKKi KO and WT mice at 4 weeks after surgery.ParameterSham WT(n = 6) IKKi KO(n = 6) 27.1960.32 4.4360.04 4.9060.10 6.5160.08 462610 117.1564.04 10.2461.28 10.5161.46 24.8561.83 10663.836781.97 28967.336357.21 64.0262.AB WT(n = 6) 27.8960.34 6.4960.08* 5.1960.13 9.9660.08* 47768 150.8562.16* 17.7562.14* 23.5861.93* 34.4461.32* 8171.176326.82* 27658.176346.37* 39.1862.40* IKKi KO(n = 6) 28.0260.40 8.5360.42*# 26001275 9.3360.76*# 12.8360.48*# 462618 149.2562.30* 24.3161.84*# 37.2363.46*# 48.3763.29*# 6694.336306.38*# 26578.176416.63*# 25.8363.11*#BW (g) HW/BW(mg/g) LW/BW(mg/g) HW/TL(mg/cm) HR (beats/min) ESP (mmHg) EDP (mmHg) ESV (ml) EDV (ml) dP/dt max (mmHg/s) dP/dt min (mmHg/s) EF( )27.5060.52 4.2960.07 5.2060.05 6.4060.13 48369 105.7461.58 9.8460.19 10.0960.44 26.8260.78 10585.476540.98 29177.346269.63 65.6061.BW,body weight;HW/BW,heart weight/body weight;LW/BW,lung weight/body weight; HW/TL,heart weight/tibial length; HR,heart rate; ESP, end-systolic pressure; EDP, end-diastolic pressure; ESV, endsystolic volume; EDV, end-diastolic volume; EF, ejection fraction; dP/dtmax, maximal rate of pressure development; dP/dtmin, maximal rate of pressure decay. *P,0.05 vs WT/sham; # P,0.05 vs WT/AB after AB. doi:10.1371/journal.pone.0053412.tFigure 3. IKKi overexpression attenuates myocyte hypertrophy in vitro. A, The inhibitory effect of IKKi overexpression on the enlargement of myocyte induced by Ang II (1 mM for 48 h). B, RT-PCR analysis of the mRNA levels of ANP and BNP induced by Ang II at the time points indicated. * P,0.05 vs WT at the 0 time point. # P,0.05 vs WT at the same time point. doi:10.1371/journal.pone.0053412.gIKKi Deficiency Promotes Cardiac HypertrophyFigure 4. Effect of IKKi on the MAPK and AKT/GSK3b/mTOR/FOXO/NFkB signaling pathways. (A ) Levels of total and phosphorylated MEK1/2, ERK1/2, JNK, P38PI3K, AKT, GSK3b, mTOR, FOXO and NFkB in the heart tissues of mice in the indicated groups (n = 6). A and C Representative blots. B and D Quantitative results. (E ) Representative blots for total and phosphorylated AKT, GSK3b, mTOR, FOXO3A, FOXO1 and NFkB after treatment with Ang II for the indicated times in H9c2 rat cardiomyocytes infected with Ad-GFP or Ad-IKKi. E Representative blots. F, Quantitative results. *P,0.05 vs. WT/sham; # P,0.05 vs. WT/AB after AB. doi:10.1371/journal.pone.0053412.gpathways, and a change in the AKT pathway is likely to be an indicator rather than a true determinant and a pharmacological target.Fibrosis is an important contributor to the.