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Modulation of RNA Polymerase II Activity by the C-Terminal Domain Phosphatase FCP1 in Development of Cardiac Dysfunction
The 18th Annual Scientific Meeting anxiety might be increased after rehabilitation. It is necessary to adequate care for the anxiety.
O-229 Prognostic Impact of Physical Activity Level in Patient with Chronic Heart Failure-A Multicenter Prospective Cohort Study SOICHIRO TADAKI1, YASUHIKO SAKATA1, YOSHIHIRO FUKUMOTO3, TOSHIRO MIURA4, TOSHIAKI KADOKAMI5, HIROYUKI DAIDA6, MASAFUMI KITAKAZE7, HIROAKI SHIMOKAWA1,2 1 Department of Cardiovascular Medicine, Tohoku University Graduate School of Medicine, Sendai, Japan, 2Department of Evidenced-Based Cardiovascular Medicine, Tohoku University Graduate School of Medicine, Sendai, Japan, 3 Department of Internal Medicine Division of Cardio-Vascular Medicine, Kurume University School of Medicine, Kurume, Japan, 4Department of General Medicine, Tokuyama Central Hospital, Shunan, Japan, 5Division of Cardiovascular Medicine, Saiseikai Futsukaichi Hospital, Chikushino, Japan, 6Department of Cardiovascular Medicine, Juntendo University School of Medicine, Tokyo, Japan, 7Cardiovascular Division of Internal Medicine, National Cerebral and Cardiovascular Center, Suita, Japan Background: Prognostic impact of physical activity (PA) level in patients with chronic heart failure (HF) is unclear. Methods: In our nationwide cohort study of 10,470 cardiovascular patients, we divided 1,886 HF patients into 3 groups according to the tertiles of their PA level calculated based on the questionnaire survey performed between April 2011 and March 2012. The relationship between PA level and incidence of cardiovascular events was examined. Results: In patients with low-, middle-, and high-PA, mean age was 72, 67, and 64 y.o., and the prevalence of females 39, 33, and 24%, respectively. Patients with low-PA was characterized by higher BNP levels (median 109.0 pg/mL), compared with those with middle-PA (102.0 pg/mL) or those with high-PA (89.7 pg/mL) (both P!0.001). During the follow-up period of 1 year, there were 32 deaths and 108 hospitalizations for worsening HF. All-cause death and worsening HF were most frequently noted in patients with low-PA (both log-rank test P!0.001). The multivariate Cox regression analysis revealed that a decrease in PA, namely from high and middle PA to low PA, was significantly associated with an increased risk of the composite endpoint of death and worsening HF (hazard ratio 1.58; 95% confidential interval; 1.23-2.04, P! 0.005). Conclusions: These results indicate that patients with HF and low PA are associated with increased incidence of death and worsening HF.
O-230 Both Tail and Globular Domains of Histone Are Acetylated by p300 During the Development of Cardiomyocyte Hypertrophy MASAFUMI FUNAMOTO1, YOICHI SUNAGAWA1,2, MASATOSHI FUJITA3, KOJI HASEGAWA2, TATSUYA MORIMOTO1 1 Division of Molecular Medicine, Graduate School of Integrated Pharmaceutical and Nutritional Sciences, University of Shizuoka, Shizuoka, Japan, 2Division of Translational Research, National Hospital Organization, Kyoto, Japan, 3Human Health Sciences, Graduate School of Medicine, Kyoto University, Kyoto, Japan Introduction: An intrinsic histone acetyltransferase (HAT), p300, is required for acetylation and the transcriptional activity of GATA4 as well as for pathological cardiomyocyte hypertrophy and the development of heart failure in vivo. Although most previously studied histone modifications are located within the flexible tails of histones, H3K122 is reported to be a novel acetylated site of histone globular domain by p300 and the acetylation of H3K122 activates gene transcriptions by destabilizing histone-DNA binding and increasing the accessibility of transactional factors to DNA. However, little is known to what extent histone modifications can directly impact on cardiac hypertrophy. Methods and Results: Treatment of phenylephrine (PE) increased the acetylation of H3K122 as well as those of H3K9 and H3K14 in tail domain of histone in cultured rat neonatal cardiomyocytes. These acetylations were significantly inhibited by knockdown of p300 by siRNA or treatment of curcumin, a p300 specific HAT inhibitor. Chromatin-immunoprecipitation assay demonstrated that PE stimulus increased the recruitment of the acetylated H3K122 and H3K9 onto ANF and BNP promoters containing the GATA element. Moreover, overexpression of p300 in mouse heart induced cardiac hypertrophy and the acetylations of H3K122, H3K9, and H3K14 in vivo. Conclusion: Our data indicated the epigenetic gene activations by p300-induced acetylations of globular and tail domains of histone were involved in cardiac hypertrophic responses.
O-231 Modulation of RNA Polymerase II Activity by the C-Terminal Domain Phosphatase FCP1 in Development of Cardiac Dysfunction SATSOHI SAKAI, TAIZO KIMURA, KAZUKO TAJIRI, HIDEKAZU MARUYAMA, SATOSHI HOMMA, TAKASHI MIYAUCHI, KAZUTAKA AONUMA Department of Cardiovascular Medicine, University of Tsukuba, Tsukuba, Japan In cardiac hypertrophy, the activation of RNA polymerase II (RNAPII) by phosphorylation of C-terminal domain (CTD) is a crucial response for cardiomyocytes; the
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phosphorylation and dephosphorylation of CTD is regulated by p-TEFb and the phosphatase FCP1, respectively. Although the role of p-TEFb in heart pathogenesis is well studied, the precise of FCP1 involvement is unclear. We created cardiomyocyte-specific FCP1 transgenic mice (FCP1-TG) using aMHC promoter. FCP1-TG showed the decreased level of myocardial CTD phosphorylation. FCP1-TG developed severe cardiac dilatation and dysfunction at 22-week old but not at 5-week old revealed by histopathology and echocardiography; however, a marker for failing heart, ANP expression, was markedly augmented even from 5-week old. The apoptosis marker cleaved caspase-3 and pro-apoptosis signal Bax was augmented in a time-dependent manner in FCP1-TG. These changes were not observed in dominant-negative FCP1 (dnFCP1)-TG. In transient transfection study in neonatal rat cardiomyocytes, FCP1 inhibited CTD phosphorylation and a hypertrophic agent (endothelin-1)-induced increase of RNA and protein synthesis; however, dnFCP1 did not affect on this phenomenon. In conclusion, myocardial FCP1-overexpression induces cardiac dysfunction accordant with apoptosis signaling probably via inhibition of RNA synthesis secondary to the suppression of CTD phosphorylation. FCP1 may be an important molecule to properly coordinate the RNAPII function and the inhibition of RNA synthesis induces heart failure probably due not able to respond to environment-associated stimuli.
O-232 Pivotal Involvement of Renin-angiotensin System in Generating Arrhythmogenic Substrates in Mice with Chronic Heart Failure and Lethal Arrhythmias CHINATSU YAMADA1, KOICHIRO KUWAHARA1, HIDEYUKI KINOSHITA1, YASUAKI NAKAGAWA1, TOSHIO NISHIKIMI1, KAZUWA NAKAO2, TAKESHI KIMURA1 1 Department of Cardiovascular Medicine, Kyoto University Graduate School of Medicine, Kyoto, Japan, 2Medical Innovation Center, Kyoto University Graduate School of Medicine, Kyoto, Japan Purpose: We investigated the contribution of renin-angiotensin system (RAS) activation to the arrhythmogenic remodeling and the underlying mechanisms. Methods: We administered direct renin inhibitor (DRI) aliskiren subcutaneously to a cardiacspecific dominant-negative form of neuron-restrictive silencer factor transgenic mice (dnNRSF-Tg), which exhibiting progressive cardiac dysfunction and lethal arrhythmias. We evaluated its effects against arrhythmogenic remodeling. Results: DRI significantly prevented the progression of pathological cardiac remodeling and improved the survival in dnNRSF-Tg. Arrhythmogenicity was substantially reduced in dnNRSF-Tg with DRI. Genetic deletion of angiotensin type 1a receptor (AT1aR) in dnNRSF-Tg similarly prevented cardiac remodeling and sudden cardiac death (SCD). In optical mapping analyses, spontaneous ventricular tachycardia (VT) and fibrillation (VF), which are initiated by a breakthrough-type focal activation and maintained by functional reentry, were observed in hearts of dnNRSF-Tg. Under constant pacing, dnNRSF-Tg hearts exhibited remarkably slowed conduction velocity contributing to generating arrhythmogenic substrates. DRI restored the conduction velocity and reduced the incidence of sustained VT. Furthermore, dnNRSF-Tg ventricles showed markedly reduced protein expression of connexin 43, which was restored with DRI. Conclusions: Renin inhibition or genetic deletion of AT1aR prevented pathological cardiac remodeling that leads to the generation of substrates to maintain VT/VF and reduced the occurrence of SCD in dnNRSF-Tg. Our findings demonstrate significant contribution of RAS activation to promoting arrhythmogenic remodeling.
O-233 Cardiac-specific Overexpression of ER Chaperone GRP78 Attenuates Doxorubicin-Induced Cardiac Dysfunction HAIYING FU, TAKASHI MATSUZAKI, SHOJI SANADA, TETSUO MINAMINO Department of Cardiovascular Medicine, Osaka University Graduate School of Medicine Background: Doxorubicin (Dox) is used in the treatment of a variety of cancers. However, its clinical application is often limited by the cardiotoxicity. Recently, we have presented a new concept that endoplasmic reticulum (ER)-initiated signaling play important roles in the pathophysiology of heart failure. Here, we evaluated the role of ER-initiated signaling in Dox-induced cardiomyopathy. Methods and Results: Electromircroscopic analysis revealed that cardiac ER was enlarged in Doxtreated mice hearts, suggesting that Dox may cause ER stress in the hearts. Consistently, Dox activated a member of ER-stress sensor, activating transcription factor-6 (ATF-6) in hearts. However, Dox failed to induce ER chaperone GRP78, which may augment ER stress in heart. Importantly, cardiac-specific overexpression of GRP78 with adeno-associated virus 9 (AAV9) reduced ER-initiated apoptosis signaling and cell death by Dox in cultured cardiomyocytes. Furthermore, overexpression of GRP78 by AAV9 or chemical ER chaperone restored cardiac dysfunction in Doxtreated mice hearts. Conclusions: Cardiac-specific overexpression of GRP78 or chemical ER chaperone attenuated Dox-induced cardiomyopathy in mice. Supplement of ER chaperone GRP78 may facilitate the safe use of Dox in patients with cancer.
O-229 Prognostic Impact of Physical Activity Level in Patient with Chronic Heart Failure-A Multicenter Prospective Cohort Study SOICHIRO TADAKI1, YASUHIKO SAKATA1, YOSHIHIRO FUKUMOTO3, TOSHIRO MIURA4, TOSHIAKI KADOKAMI5, HIROYUKI DAIDA6, MASAFUMI KITAKAZE7, HIROAKI SHIMOKAWA1,2 1 Department of Cardiovascular Medicine, Tohoku University Graduate School of Medicine, Sendai, Japan, 2Department of Evidenced-Based Cardiovascular Medicine, Tohoku University Graduate School of Medicine, Sendai, Japan, 3 Department of Internal Medicine Division of Cardio-Vascular Medicine, Kurume University School of Medicine, Kurume, Japan, 4Department of General Medicine, Tokuyama Central Hospital, Shunan, Japan, 5Division of Cardiovascular Medicine, Saiseikai Futsukaichi Hospital, Chikushino, Japan, 6Department of Cardiovascular Medicine, Juntendo University School of Medicine, Tokyo, Japan, 7Cardiovascular Division of Internal Medicine, National Cerebral and Cardiovascular Center, Suita, Japan Background: Prognostic impact of physical activity (PA) level in patients with chronic heart failure (HF) is unclear. Methods: In our nationwide cohort study of 10,470 cardiovascular patients, we divided 1,886 HF patients into 3 groups according to the tertiles of their PA level calculated based on the questionnaire survey performed between April 2011 and March 2012. The relationship between PA level and incidence of cardiovascular events was examined. Results: In patients with low-, middle-, and high-PA, mean age was 72, 67, and 64 y.o., and the prevalence of females 39, 33, and 24%, respectively. Patients with low-PA was characterized by higher BNP levels (median 109.0 pg/mL), compared with those with middle-PA (102.0 pg/mL) or those with high-PA (89.7 pg/mL) (both P!0.001). During the follow-up period of 1 year, there were 32 deaths and 108 hospitalizations for worsening HF. All-cause death and worsening HF were most frequently noted in patients with low-PA (both log-rank test P!0.001). The multivariate Cox regression analysis revealed that a decrease in PA, namely from high and middle PA to low PA, was significantly associated with an increased risk of the composite endpoint of death and worsening HF (hazard ratio 1.58; 95% confidential interval; 1.23-2.04, P! 0.005). Conclusions: These results indicate that patients with HF and low PA are associated with increased incidence of death and worsening HF.
O-230 Both Tail and Globular Domains of Histone Are Acetylated by p300 During the Development of Cardiomyocyte Hypertrophy MASAFUMI FUNAMOTO1, YOICHI SUNAGAWA1,2, MASATOSHI FUJITA3, KOJI HASEGAWA2, TATSUYA MORIMOTO1 1 Division of Molecular Medicine, Graduate School of Integrated Pharmaceutical and Nutritional Sciences, University of Shizuoka, Shizuoka, Japan, 2Division of Translational Research, National Hospital Organization, Kyoto, Japan, 3Human Health Sciences, Graduate School of Medicine, Kyoto University, Kyoto, Japan Introduction: An intrinsic histone acetyltransferase (HAT), p300, is required for acetylation and the transcriptional activity of GATA4 as well as for pathological cardiomyocyte hypertrophy and the development of heart failure in vivo. Although most previously studied histone modifications are located within the flexible tails of histones, H3K122 is reported to be a novel acetylated site of histone globular domain by p300 and the acetylation of H3K122 activates gene transcriptions by destabilizing histone-DNA binding and increasing the accessibility of transactional factors to DNA. However, little is known to what extent histone modifications can directly impact on cardiac hypertrophy. Methods and Results: Treatment of phenylephrine (PE) increased the acetylation of H3K122 as well as those of H3K9 and H3K14 in tail domain of histone in cultured rat neonatal cardiomyocytes. These acetylations were significantly inhibited by knockdown of p300 by siRNA or treatment of curcumin, a p300 specific HAT inhibitor. Chromatin-immunoprecipitation assay demonstrated that PE stimulus increased the recruitment of the acetylated H3K122 and H3K9 onto ANF and BNP promoters containing the GATA element. Moreover, overexpression of p300 in mouse heart induced cardiac hypertrophy and the acetylations of H3K122, H3K9, and H3K14 in vivo. Conclusion: Our data indicated the epigenetic gene activations by p300-induced acetylations of globular and tail domains of histone were involved in cardiac hypertrophic responses.
O-231 Modulation of RNA Polymerase II Activity by the C-Terminal Domain Phosphatase FCP1 in Development of Cardiac Dysfunction SATSOHI SAKAI, TAIZO KIMURA, KAZUKO TAJIRI, HIDEKAZU MARUYAMA, SATOSHI HOMMA, TAKASHI MIYAUCHI, KAZUTAKA AONUMA Department of Cardiovascular Medicine, University of Tsukuba, Tsukuba, Japan In cardiac hypertrophy, the activation of RNA polymerase II (RNAPII) by phosphorylation of C-terminal domain (CTD) is a crucial response for cardiomyocytes; the
JHFS
S185
phosphorylation and dephosphorylation of CTD is regulated by p-TEFb and the phosphatase FCP1, respectively. Although the role of p-TEFb in heart pathogenesis is well studied, the precise of FCP1 involvement is unclear. We created cardiomyocyte-specific FCP1 transgenic mice (FCP1-TG) using aMHC promoter. FCP1-TG showed the decreased level of myocardial CTD phosphorylation. FCP1-TG developed severe cardiac dilatation and dysfunction at 22-week old but not at 5-week old revealed by histopathology and echocardiography; however, a marker for failing heart, ANP expression, was markedly augmented even from 5-week old. The apoptosis marker cleaved caspase-3 and pro-apoptosis signal Bax was augmented in a time-dependent manner in FCP1-TG. These changes were not observed in dominant-negative FCP1 (dnFCP1)-TG. In transient transfection study in neonatal rat cardiomyocytes, FCP1 inhibited CTD phosphorylation and a hypertrophic agent (endothelin-1)-induced increase of RNA and protein synthesis; however, dnFCP1 did not affect on this phenomenon. In conclusion, myocardial FCP1-overexpression induces cardiac dysfunction accordant with apoptosis signaling probably via inhibition of RNA synthesis secondary to the suppression of CTD phosphorylation. FCP1 may be an important molecule to properly coordinate the RNAPII function and the inhibition of RNA synthesis induces heart failure probably due not able to respond to environment-associated stimuli.
O-232 Pivotal Involvement of Renin-angiotensin System in Generating Arrhythmogenic Substrates in Mice with Chronic Heart Failure and Lethal Arrhythmias CHINATSU YAMADA1, KOICHIRO KUWAHARA1, HIDEYUKI KINOSHITA1, YASUAKI NAKAGAWA1, TOSHIO NISHIKIMI1, KAZUWA NAKAO2, TAKESHI KIMURA1 1 Department of Cardiovascular Medicine, Kyoto University Graduate School of Medicine, Kyoto, Japan, 2Medical Innovation Center, Kyoto University Graduate School of Medicine, Kyoto, Japan Purpose: We investigated the contribution of renin-angiotensin system (RAS) activation to the arrhythmogenic remodeling and the underlying mechanisms. Methods: We administered direct renin inhibitor (DRI) aliskiren subcutaneously to a cardiacspecific dominant-negative form of neuron-restrictive silencer factor transgenic mice (dnNRSF-Tg), which exhibiting progressive cardiac dysfunction and lethal arrhythmias. We evaluated its effects against arrhythmogenic remodeling. Results: DRI significantly prevented the progression of pathological cardiac remodeling and improved the survival in dnNRSF-Tg. Arrhythmogenicity was substantially reduced in dnNRSF-Tg with DRI. Genetic deletion of angiotensin type 1a receptor (AT1aR) in dnNRSF-Tg similarly prevented cardiac remodeling and sudden cardiac death (SCD). In optical mapping analyses, spontaneous ventricular tachycardia (VT) and fibrillation (VF), which are initiated by a breakthrough-type focal activation and maintained by functional reentry, were observed in hearts of dnNRSF-Tg. Under constant pacing, dnNRSF-Tg hearts exhibited remarkably slowed conduction velocity contributing to generating arrhythmogenic substrates. DRI restored the conduction velocity and reduced the incidence of sustained VT. Furthermore, dnNRSF-Tg ventricles showed markedly reduced protein expression of connexin 43, which was restored with DRI. Conclusions: Renin inhibition or genetic deletion of AT1aR prevented pathological cardiac remodeling that leads to the generation of substrates to maintain VT/VF and reduced the occurrence of SCD in dnNRSF-Tg. Our findings demonstrate significant contribution of RAS activation to promoting arrhythmogenic remodeling.
O-233 Cardiac-specific Overexpression of ER Chaperone GRP78 Attenuates Doxorubicin-Induced Cardiac Dysfunction HAIYING FU, TAKASHI MATSUZAKI, SHOJI SANADA, TETSUO MINAMINO Department of Cardiovascular Medicine, Osaka University Graduate School of Medicine Background: Doxorubicin (Dox) is used in the treatment of a variety of cancers. However, its clinical application is often limited by the cardiotoxicity. Recently, we have presented a new concept that endoplasmic reticulum (ER)-initiated signaling play important roles in the pathophysiology of heart failure. Here, we evaluated the role of ER-initiated signaling in Dox-induced cardiomyopathy. Methods and Results: Electromircroscopic analysis revealed that cardiac ER was enlarged in Doxtreated mice hearts, suggesting that Dox may cause ER stress in the hearts. Consistently, Dox activated a member of ER-stress sensor, activating transcription factor-6 (ATF-6) in hearts. However, Dox failed to induce ER chaperone GRP78, which may augment ER stress in heart. Importantly, cardiac-specific overexpression of GRP78 with adeno-associated virus 9 (AAV9) reduced ER-initiated apoptosis signaling and cell death by Dox in cultured cardiomyocytes. Furthermore, overexpression of GRP78 by AAV9 or chemical ER chaperone restored cardiac dysfunction in Doxtreated mice hearts. Conclusions: Cardiac-specific overexpression of GRP78 or chemical ER chaperone attenuated Dox-induced cardiomyopathy in mice. Supplement of ER chaperone GRP78 may facilitate the safe use of Dox in patients with cancer.