Auto-acetylation stabilizes p300 in cardiac myocytes during acute oxidative stress, promoting STAT3 accumulation and cell survival
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The nuclear acetyltransferase p300 is rapidly and stably induced in the heart during hemodynamic stress, but the mechanism of this induction is unknown. To determine the role of oxidative stress in p300 induction, we exposed neonatal rat cardiac myocytes to doxorubicin (DOX, 1 μM) or its vehicle, and monitored p300 protein content and stability for 24 h. Levels of p300 rose substantially within 1 h and remained elevated for at least 24 h, while p300 transcript levels declined. In the presence of cycloheximide, the estimated half-life of p300 in control cells was approximately 4.5 h, typical of an immediate-early response protein. DOX treatment prolonged p300 t1/2 to >24 h, indicating that the sharp rise in p300 levels was attributable to rapid protein stabilization. p300 stabilization was entirely due to an increase in acetylated p300 species with greatly enhanced resistance to proteasomal degradation. The half-life of p300 was dependent on its acetyltransferase activity, falling in the presence of p300 inhibitors curcumin and anacardic acid, and increasing with histone deacetylase (HDAC) inhibition. At the same time, acetyl-STAT3, phospho-STAT3-(Tyr 705) and -(Ser 727) increased, together with a prolongation of STAT3 half-life. SiRNA-mediated p300 knockdown abrogated all of these effects, and strongly enhanced DOX-mediated myocyte apoptosis. We conclude that DOX induces an acute amplification of p300 levels through auto-acetylation and stabilization. In turn, elevated p300 provides a key defense against acute oxidative stress in cardiac myocytes by acetylation, activation, and stabilization of STAT3. Our results suggest that HDAC inhibitors could potentially reduce acute anthracycline-mediated cardiotoxicity by promoting p300 auto-acetylation.
KeywordsAcetyltransferase p300 HDAC inhibitor Curcumin Apoptosis Proteasome Anthracycline Cardiotoxicity Stat3 Acetylation Post-translational regulation
The authors are grateful to Dr. Paul Kurlansky for insightful comments on the text. This study was supported by grants from the National Institutes of Health (NHLBI R01- HL71094 to N.H.B.) and the Florida Heart Research Institute (to N.H.B.), and an American Heart Association Greater Southeastern Affiliate Predoctoral Fellowship award (to S.J.).
Conflict of interest
None of the authors has any financial or other conflict of interest relative to the material presented in this manuscript.
- 20.Hilfiker-Kleiner D, Hilfiker A, Fuchs M, Kaminski K, Schaefer A, Schieffer B, Hillmer A, Schmiedl A, Ding Z, Podewski E, Poli V, Schneider MD, Schulz R, Park JK, Wollert KC, Drexler H (2004) Signal transducer and activator of transcription 3 is required for myocardial capillary growth, control of interstitial matrix deposition, and heart protection from ischemic injury. Circ Res 95(2):187–195PubMedCrossRefGoogle Scholar
- 24.Ray S, Sherman CT, Lu M, Brasier AR (2002) Angiotensinogen gene expression is dependent on signal transducer and activator of transcription 3-mediated p300/cAMP response element binding protein-binding protein coactivator recruitment and histone acetyltransferase activity. Mol Endocrinol 16(4):824–836PubMedCrossRefGoogle Scholar
- 25.Negoro S, Kunisada K, Fujio Y, Funamoto M, Darville MI, Eizirik DL, Osugi T, Izumi M, Oshima Y, Nakaoka Y, Hirota H, Kishimoto T, Yamauchi-Takihara K (2001) Activation of signal transducer and activator of transcription 3 protects cardiomyocytes from hypoxia/reoxygenation-induced oxidative stress through the upregulation of manganese superoxide dismutase. Circulation 104(9):979–981PubMedCrossRefGoogle Scholar
- 26.Harada M, Qin Y, Takano H, Minamino T, Zou Y, Toko H, Ohtsuka M, Matsuura K, Sano M, Nishi J, Iwanaga K, Akazawa H, Kunieda T, Zhu W, Hasegawa H, Kunisada K, Nagai T, Nakaya H, Yamauchi-Takihara K, Komuro I (2005) G-CSF prevents cardiac remodeling after myocardial infarction by activating the Jak-Stat pathway in cardiomyocytes. Nat Med 11(3):305–311PubMedCrossRefGoogle Scholar
- 35.Gray MJ, Zhang J, Ellis LM, Semenza GL, Evans DB, Watowich SS, Gallick GE (2005) HIF-1alpha, STAT3, CBP/p300 and Ref-1/APE are components of a transcriptional complex that regulates Src-dependent hypoxia-induced expression of VEGF in pancreatic and prostate carcinomas. Oncogene 24(19):3110–3120PubMedCrossRefGoogle Scholar
- 40.Daino H, Matsumura I, Takada K, Odajima J, Tanaka H, Ueda S, Shibayama H, Ikeda H, Hibi M, Machii T, Hirano T, Kanakura Y (2000) Induction of apoptosis by extracellular ubiquitin in human hematopoietic cells: possible involvement of STAT3 degradation by proteasome pathway in interleukin 6-dependent hematopoietic cells. Blood 95(8):2577–2585PubMedGoogle Scholar
- 72.Ganz PA, Hussey MA, Moinpour CM, Unger JM, Hutchins LF, Dakhil SR, Giguere JK, Goodwin JW, Martino S, Albain KS (2008) Late cardiac effects of adjuvant chemotherapy in breast cancer survivors treated on Southwest Oncology Group protocol s8897. J Clin Oncol 26(8):1223–1230PubMedCrossRefGoogle Scholar
- 73.Morris PG, Chen C, Steingart R, Fleisher M, Lin N, Moy B, Come S, Sugarman S, Abbruzzi A, Lehman R, Patil S, Dickler M, McArthur HL, Winer E, Norton L, Hudis CA, Dang CT (2011) Troponin I and C-reactive protein are commonly detected in patients with breast cancer treated with dose-dense chemotherapy incorporating trastuzumab and lapatinib. Clin Cancer Res 17(10):3490–3499PubMedCrossRefGoogle Scholar