Optogenetic control of contractile function in skeletal muscle
Tobias Bruegmann1,2, Tobias van Bremen3, Christoph C Vogt1
1Institute of Physiology I, University of Bonn, Life and Brain Center, Sigmund-Freud-Strasse 25, 53127 Bonn, Germany.
Nature Communications
|June 3, 2015
Summary
Direct optogenetic stimulation of skeletal muscle using Channelrhodopsin-2 (ChR2) generates significant force for precise muscle activation. This method shows promise for restoring vocal cord mobility in laryngeal paralysis.
Area of Science:
- Optogenetics
- Muscle Physiology
- Biotechnology
Background:
- Optogenetic stimulation offers precise control over cellular activity.
- Skeletal muscle activation typically relies on electrical stimulation.
- Restoring function in paralyzed muscles, like vocal cords, presents a therapeutic challenge.
Purpose of the Study:
- To investigate direct optogenetic stimulation of skeletal muscle.
- To evaluate the force generated by optogenetically stimulated muscle.
- To explore the therapeutic potential for vocal cord dysfunction.
Main Methods:
- Utilized transgenic mice expressing Channelrhodopsin-2 (ChR2) in skeletal muscle.
- Applied light pulses (5 ms, 30 Hz) to induce tetanic contractions.
- Demonstrated selective muscle activation in explanted larynges and in vivo via viral gene delivery.
Main Results:
- Optogenetic stimulation achieved 84% of maximal force compared to electrical stimulation.
- Selective activation of intralaryngeal muscles enabled vocal cord opening and closing.
- Systemic adeno-associated virus injection led to sufficient ChR2 expression for functional outcomes.
Conclusions:
- Direct optogenetic stimulation of skeletal muscle is effective in generating substantial force.
- This technique allows for localized and cell-type-specific muscle activation.
- Optogenetics presents a viable therapeutic strategy for conditions like laryngeal paralysis.
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