Green Light Exposure Elicits Anti-inflammation, Endogenous Opioid Release and Dampens Synaptic Potentiation to Relieve Post-surgical Pain.

TitleGreen Light Exposure Elicits Anti-inflammation, Endogenous Opioid Release and Dampens Synaptic Potentiation to Relieve Post-surgical Pain.
Publication TypeJournal Article
Year of Publication2023
AuthorsMartin LF, Cheng K, Washington SM, Denton M, Goel V, Khandekar M, Largent-Milnes TM, Patwardhan A, Ibrahim MM
JournalJ Pain
Date Published2023 Mar
KeywordsAnalgesics, Opioid, Animals, Anti-Inflammatory Agents, Female, Humans, Ibuprofen, Male, Morphine, Neuroinflammatory Diseases, Opioid Peptides, Pain, Postoperative, Rats

Light therapy improves multiple conditions such as seasonal affective disorders, circadian rhythm dysregulations, and neurodegenerative diseases. However, little is known about its potential benefits in pain management. While current pharmacologic methods are effective in many cases, the associated side effects can limit their use. Non-pharmacological methods would minimize drug dependence, facilitating a reduction of the opioid burden. Green light therapy has been shown to be effective in reducing chronic pain in humans and rodents. However, its underlying mechanisms remain incompletely defined. In this study, we demonstrate that green light exposure reduced postsurgical hypersensitivity in rats. Moreover, this therapy potentiated the antinociceptive effects of morphine and ibuprofen on mechanical allodynia in male rats. Importantly, in female rats, GLED potentiated the antinociceptive effects of morphine but did not affect that of ibuprofen. We showed that green light increases endogenous opioid levels while lessening synaptic plasticity and neuroinflammation. Importantly, this study reveals new insights into how light exposure can affect neuroinflammation and plasticity in both genders. Clinical translation of these results could provide patients with improved pain control and decrease opioid consumption. Given the noninvasive nature of green light, this innovative therapy would be readily implementable in hospitals. PERSPECTIVE: This study provides a potential additional therapy to decrease postsurgical pain. Given the safety, availability, and the efficacy of green light therapy, there is a significant potential for advancing the green light therapy to clinical trials and eventual translation to clinical settings.

Alternate JournalJ Pain
PubMed ID36283655
PubMed Central IDPMC9991952
Grant ListK08 NS104272 / NS / NINDS NIH HHS / United States
R01 AT009716 / AT / NCCIH NIH HHS / United States
Faculty Member Reference: 
Mohab M. Ibrahim, PhD, MD
Tally Largent-Milnes, PhD