Near-Infrared Light Exposure Triggers ROS to Downregulate Inflammatory Cytokines Induced by SARS-CoV-2 Spike Protein...

Area of Science:

• Immunology
• Biophysics
• Cell Biology

Background:

• Exaggerated immune responses, like cytokine storms, drive mortality in SARS-CoV-2 infections.
• Existing therapies face challenges with novel viral variants.
• Infrared therapy is a long-established, non-invasive treatment for inflammation, but its mechanisms are unclear.

Purpose of the Study:

• To investigate if near-infrared (NIR) light can reduce inflammatory cytokines triggered by SARS-CoV-2 spike protein or LPS.
• To elucidate the underlying cellular mechanisms of NIR light's anti-inflammatory effects.

Main Methods:

• Human primary alveolar and macrophage cells were exposed to NIR light.
• Cells were stimulated with SARS-CoV-2 spike protein or lipopolysaccharide (LPS).
• Pro-inflammatory and anti-inflammatory cytokine levels were measured.
• Mitochondrial metabolism, reactive oxygen species (ROS), and antioxidant gene transcription were analyzed.

Main Results:

• NIR light treatment dramatically reduced pro-inflammatory cytokines and upregulated anti-inflammatory cytokines within days.
• NIR light stimulated mitochondrial metabolism and induced transient ROS bursts.
• Activated antioxidant gene transcription led to ROS and inflammatory cytokine downregulation.
• A causal link was established between NIR-induced ROS and the suppression of SARS-CoV-2-triggered inflammation.

Conclusions:

• NIR light therapy demonstrates potential for downregulating detrimental inflammatory responses in SARS-CoV-2 infection.
• The mechanism involves enhanced mitochondrial activity, ROS induction, and subsequent antioxidant responses.
• This non-invasive approach could offer a novel therapeutic strategy against SARS-CoV-2 variants and other inflammatory diseases, pending clinical validation.