View publication

↩ Back to all publications
Publication
PropertyValue
Working Groups AG Maier, AG Nikolaev
SubprojectA01, A03
Open AccessOpen Access Yes
Publication TypeJournal Article
Peer ReviewedUnknown
PMIDPubMed ID 24812278
DOIDOI 10.1093/cvr/cvu120
Publication Year2014
TitleTubulin polymerization disrupts cardiac β-adrenergic regulation of late INa Wikidata
JournalCardiovascular Research
ISSN0008-6363
eISSN1755-3245
URL http://cardiovascres.oxfordjournals.org/content/early/2014/05/08/cvr.cvu120
Pagescvu120
Journal AbbreviationCardiovasc Res
ExtraAims The anticancer drug paclitaxel (TXL) that polymerizes microtubules is associated with arrhythmias and sinus node dysfunction. TXL can alter membrane expression of Na channels (NaV1.5) and Na current (INa) but the mechanisms are unknown. Ca/CaM-dependent protein kinase II (CaMKII) can be activated by β-adrenergic stimulation and regulates INa gating. We tested, whether TXL interferes with isoproterenol (ISO)-induced activation of CaMKII and consequent INa regulation. Methods and Results In wild-type (WT) mouse myocytes, the addition of ISO (1 µmol/L) resulted in increased CaMKII autophosphorylation (Western blotting). This increase was completely abolished after pre-treatment with TXL (100 µmol/L, 1.5 h). The mechanism was further investigated in human embryonic kidney cells. TXL inhibited the ISO-induced β-arrestin translocation. Interestingly, both knockdown of β-arrestin 2 expression using small interfering RNA or inhibition of exchange protein directly activated by cAMP (Epac) blocked the ISO-induced CaMKII autophosphorylation similar to TXL. The generation of cAMP, however, was unaltered (Epac1-camps). CaMKII-dependent Na channel function was measured using patch-clamp technic in isolated cardiomyoctes. ISO stimulation failed to induce CaMKII-dependent enhancement of late INa and Na channel inactivation (negative voltage shift in steady-state activation and enhanced intermediate inactivation) after TXL pre-incubation. Consistent with this, TXL also inhibited ISO-induced CaMKII-specific Na channel phosphorylation (at serine 571 of NaV1.5). Conclusion TXL preincubation disrupts the ISO-dependent CaMKII activation and consequent Na channel regulation. This may be important for patients receiving TXL treatments but also relevant for conditions of increased CaMKII expression and enhanced β-adrenergic stimulation like in heart failure. PMID: 24812278
AuthorsDybkova N, Wagner S, Backs J, Hund TJ, Mohler PJ, Sowa T, Nikolaev VO, Maier LS
First AuthorDybkova N
Last AuthorMaier LS
ScholiaScholia Wikidata-based representation at Scholia

 External Resources

 academic...20.pdf  Article fulltext

 gro-2/32981  GRO.publications identifier

 10090  NCBI Taxonomy (Mus musculus)

 0000-0002-7529-5179  ORCID identifier (Viacheslav O. Nikolaev)

 0000-0001-9915-4429  ORCID identifier (Lars S. Maier)

 031t5w623  ROR identifier (031t5w623, German Centre for Cardiovascular Research)

 021ft0n22  ROR identifier (021ft0n22, University Medical Center Göttingen)

 SCR_003070  SciCrunch identifier (RRID:SCR_003070, ImageJ)

 academic...486411  Supplemental material

 Q34048285  Wikidata ID