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Cytosolic Calcium Measurements in Renal Epithelial Cells by Flow Cytometry
Published on: October 28, 2014
Calcium-dependent physiologic and pathologic stimulus-metabolic response coupling in hepatocytes.
Lawrence D Gaspers1, Elisabeth Mémin, Andrew P Thomas
1Department of Pharmacology and Physiology, University of Medicine and Dentistry of New Jersey, 185 South Orange Avenue, Newark, NJ 07103, United States. Larry.Gaspers@UMDNJ.EDU
Cell Calcium
|May 9, 2012
Summary
Calcium signals coordinate cellular responses with energy production. Brief calcium spikes, not sustained signals, optimize this process, reducing harmful reactive oxygen species (ROS) and promoting cell survival.
Area of Science:
- Cellular biology
- Biochemistry
- Physiology
Background:
- Calcium signaling is crucial for cellular functions, including energy production.
- Calcium-dependent mitochondrial activation enhances energy supply but can produce harmful reactive oxygen species (ROS).
Purpose of the Study:
- To review the coordination between calcium signaling and metabolic energy production.
- To explore how signal characteristics influence cellular outcomes and ROS generation.
Main Methods:
- Review of existing literature and data, particularly from hepatocyte studies.
- Analysis of calcium signal characteristics (frequency modulation) and their impact on mitochondrial metabolism and ROS production.
Main Results:
- Calcium signals regulate mitochondrial oxidative metabolism via NADH production and respiratory chain flux.
- Signal strength encoded by spike frequency (frequency modulation) enhances signal fidelity.
- Brief calcium spikes/oscillations mitigate negative consequences of mitochondrial activation, including excess ROS.
Conclusions:
- Frequency modulation of calcium signals is key to balancing energy production with cellular protection.
- Optimized calcium signaling reduces pathological ROS generation and prevents cell death.
- Understanding these mechanisms is vital for both physiological and pathological conditions in hepatocytes.
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