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11:42
Measurement of Total Calcium in Neurons by Electron Probe X-ray Microanalysis
Published on: November 20, 2013
Mitochondrial DNA mutations affect calcium handling in differentiated neurons
Andrew J Trevelyan1, Denise M Kirby, Tora K Smulders-Srinivasan
1Mitochondrial Research Group, Institute for Ageing and Health Medical School, Newcastle University, Framlington Place, Newcastle upon Tyne, NE2 4HH, England. a.j.trevelyan@gmail.com
Brain : a Journal of Neurology
|March 9, 2010
Summary
Mitochondrial DNA mutations impair neuronal calcium regulation, causing prolonged calcium buildup after repeated stimulation. This suggests calcium-handling deficits contribute to neurological symptoms in patients.
Area of Science:
- Neuroscience
- Cell Biology
- Genetics
Background:
- Mitochondrial DNA mutations are linked to neurological disorders.
- Mitochondria play a crucial role in cellular calcium buffering.
- Deficits in neuronal calcium homeostasis are a potential mechanism for mitochondrial disease pathology.
Purpose of the Study:
- To investigate the impact of mitochondrial DNA mutations on neuronal calcium handling.
- To determine if impaired calcium homeostasis contributes to the neurological symptoms associated with mitochondrial mutations.
Main Methods:
- Utilized cybrid embryonic stem cell lines with distinct mitochondrial DNA mutations.
- Examined neuronal calcium responses using Oregon Green BAPTA-1 dye.
- Applied focal glutamatergic stimuli to induce transient intracellular calcium rises.
Main Results:
- Mitochondrial mutations did not affect calcium transients from single stimuli.
- Repeated stimuli led to progressively slower calcium transient decay in mutant cell lines.
- Sustained high intracellular calcium levels were observed in mutant neurons after repetitive stimulation.
Conclusions:
- Neuronal calcium-handling deficits are a likely contributor to the pathology observed in mitochondrial DNA mutation patients.
- Impaired calcium regulation in neurons may underlie the neurological symptoms of mitochondrial diseases.
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