Transcranial Photobiomodulation Modulates Oxidative Stress Biomarkers and Complex IV Activity in Anhedonic-Like...

Area of Science:

• Neuroscience
• Biomedical Engineering
• Pharmacology

Background:

• Major depressive disorder (MDD) is a widespread condition with suboptimal treatment outcomes.
• Transcranial photobiomodulation (tPBM) is an emerging non-invasive therapy using red to near-infrared light, but its mechanisms and optimal parameters require further investigation.
• The chronic mild stress (CMS) model effectively simulates MDD-like phenotypes in rodents.

Purpose of the Study:

• To investigate the effects of red and infrared tPBM on behavioral and biological parameters in a CMS-induced rat model of MDD.
• To explore the potential of tPBM in ameliorating oxidative stress and enhancing mitochondrial function as mechanisms for treating MDD.

Main Methods:

• Male Wistar rats were subjected to CMS for five weeks, then categorized into resilient (CMS-R) and susceptible (CMS-S) groups.
• CMS-S rats received sham treatment, red tPBM (600 nm), or infrared tPBM (840 nm). A non-stressed control group was included.
• Behavioral assessment (sucrose consumption test) and biological analyses (TBARS, TEAC, CCO, NO) in the prefrontal cortex and blood were performed.

Main Results:

• Both red and infrared tPBM significantly increased sucrose consumption in CMS-S rats compared to sham treatment.
• Red tPBM reduced peripheral lipid damage (TBARS) to levels similar to non-stressed controls.
• Infrared tPBM increased hippocampal nitric oxide (NO) levels and prefrontal cortex mitochondrial complex IV (CCO) activity, with CCO levels comparable to controls.

Conclusions:

• tPBM, using either red or infrared wavelengths, demonstrates significant efficacy in improving both behavioral and biological parameters in a rodent model of MDD.
• tPBM therapy holds promise for MDD management by mitigating oxidative stress and improving mitochondrial function.
• Further research into tPBM's therapeutic potential for major depressive disorder is warranted.