Calcium oscillations triggered by cardiotonic steroids.
Jacopo M Fontana1, Ievgeniia Burlaka, Georgiy Khodus
1Department of Women and Children's Health, Karolinska Institutet, Stockholm, Sweden.
The FEBS Journal
|July 30, 2013
Summary
Cardiotonic steroids activate the sodium-potassium pump (Na(+), K(+)-ATPase or NKA) to initiate signaling. This process involves calcium oscillations, activating NF-κB and increasing the anti-apoptotic factor Bcl-xL for tissue protection.
Area of Science:
- Cellular signaling
- Molecular biology
- Cardiovascular research
Background:
- Na(+), K(+)-ATPase (NKA) traditionally known as an ion pump.
- Recent studies reveal NKA's role as a signal transducer.
- Cardiotonic steroids are specific NKA ligands.
Purpose of the Study:
- To review the signaling pathway initiated by cardiotonic steroids via NKA.
- To elucidate the mechanism of calcium oscillations and downstream effects.
- To discuss the potential tissue-protective role of this signaling pathway.
Main Methods:
- Review of existing literature on NKA signaling.
- Description of cardiotonic steroid-NKA interactions.
- Analysis of calcium (Ca2+) oscillations and NF-κB activation.
Main Results:
- Cardiotonic steroids trigger slow Ca2+ oscillations by linking NKA with the inositol trisphosphate receptor.
- This Ca2+ signal activates the NF-κB subunit p65.
- Increased expression of the antiapoptotic factor Bcl-xL is observed.
Conclusions:
- NKA acts as a crucial signal transducer in response to cardiotonic steroids.
- The NKA-mediated signaling pathway influences cellular apoptosis and survival.
- This pathway holds potential for tissue-protective therapeutic strategies.
Keywords:
Ca2+ signalingNF-κBNa+-K+-ATPaseSrc kinaseapoptosiscardiotonic steroidsinositol trisphosphate receptorintracellular Ca2+ oscillationsorgan developmentouabainMore Related Videos
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