Safe Mitochondrial Activation Through Photobiomodulation: Distinct Red and Near-Infrared Responses in Normal and...

Area of Science:

• Biomedical Engineering
• Cell Biology
• Photomedicine

Background:

• Photobiomodulation (PBM) utilizes red or near-infrared light to enhance cellular functions.
• The safety of PBM on malignant cells is not fully understood.
• Skeletal muscle regeneration and cancer therapy are key areas of interest for PBM applications.

Purpose of the Study:

• To investigate the wavelength- and fluence-dependent effects of PBM on skeletal muscle and cancer cells.
• To assess the impact of PBM on cell viability, reactive oxygen species (ROS) production, and ATP levels.
• To determine the bioenergetic safety of PBM for potential therapeutic applications.

Main Methods:

• Murine myoblasts (C2C12) and human lung adenocarcinoma cells (A549) were treated with 660 nm LED or 830 nm NIR laser light.
• Light exposure varied in fluence from 0 to 20 J/cm².
• Cell viability (CCK-8 assay), ROS levels, and ATP concentrations were quantified.

Main Results:

• PBM induced a biphasic response in C2C12 cells, with optimal viability and ATP levels at 5 J/cm² under NIR light, accompanied by moderate ROS increase.
• A549 cells demonstrated stable or slightly decreased viability despite elevated ROS, indicating differential redox sensitivity.
• Both red and NIR wavelengths stimulated mitochondrial activity in muscle cells without overstimulation in cancer cells.

Conclusions:

• PBM exhibits wavelength- and cell type-specific effects on cellular bioenergetics.
• The findings suggest PBM is bioenergetically safe and may be suitable for skeletal muscle regeneration research.
• Differential responses highlight the need for tailored PBM protocols in therapeutic settings.