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Published on: June 3, 2018
Multiple signaling pathways coordinately mediate reactive oxygen species dependent cardiomyocyte hypertrophy
Indira K Adiga1, Renuka R Nair
1Division of Cellular and Molecular Cardiology, Sree Chitra Tirunal Institute for Medical Sciences and Technology, Thiruvananthapuram, India.
Cell Biochemistry and Function
|February 20, 2008
Summary
Reactive oxygen species (ROS) induce cardiomyocyte hypertrophy by activating multiple pathways. Inhibiting any single pathway blocked ROS-induced cardiac cell growth, suggesting coordinated signaling in oxidative stress response.
Area of Science:
- Cardiovascular Biology
- Cellular Signaling
- Oxidative Stress Research
Background:
- Cardiac myocytes undergo hypertrophy in response to increased demand.
- Reactive oxygen species (ROS) are key mediators linking mechanical stimuli to cellular responses.
- Mitogen-activated protein kinase (MAPK), protein kinase C (PKC), and calcineurin are implicated in cardiac hypertrophy.
Purpose of the Study:
- To confirm the role of ROS in inducing cardiomyocyte hypertrophy.
- To investigate the contribution of specific signaling pathways in ROS-mediated cardiac hypertrophy.
Main Methods:
- Cultured newborn rat heart cells were used to study cellular responses.
- Enzyme-generated ROS (hypoxanthine-xanthine oxidase) were applied.
- Pathway-specific inhibitors were employed to dissect signaling mechanisms.
Main Results:
- ROS exposure led to cardiomyocyte hypertrophy.
- Inhibition of MAPK, PKC, or calcineurin individually prevented ROS-induced hypertrophy.
- This indicates a coordinated activation of these pathways by oxidative stress.
Conclusions:
- Oxidative stress is a significant inducer of cardiomyocyte hypertrophy.
- The hypertrophic response to ROS involves the coordinated action of MAPK, PKC, and calcineurin pathways.
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