New Brain Molecule Offers Insights Into Migraine-Related Light Sensitivity

Recent research conducted by scientists from the UK, Australia, and China has uncovered a critical role played by a brain molecule called NEAT1 in the development of light sensitivity, or photophobia, which is a common and often debilitating symptom experienced during migraines. Published in The Journal of Headache and Pain, the study reveals how NEAT1 influences the brain's pain pathways and contributes to heightened responses to light.

NEAT1 is a type of long noncoding RNA, a molecule that does not code for proteins but actively regulates various cellular functions in the nervous system. While it is known to be involved in inflammation and stress responses, its specific impact on migraine symptoms like photophobia was not fully understood until now.

The researchers used a chemical agent to induce light sensitivity in mice, mimicking migraine symptoms in humans. They focused on the trigeminal ganglion, a nerve cluster involved in migraine pain. During light sensitivity episodes, NEAT1 levels surged in this region. Reducing NEAT1 levels in the mice resulted in decreased light sensitivity, indicating a direct role in the process.

Further analysis showed that NEAT1 interferes with a microRNA called miR-196a-5p, which normally suppresses the gene Trpm3. Trpm3 encodes a protein crucial for nerve signaling and pain perception. Elevated NEAT1 binds to miR-196a-5p, preventing it from regulating Trpm3. This results in increased Trpm3 activity, nerve hypersensitivity, and a greater likelihood of light becoming painful.

"In essence, NEAT1 disrupts the balance of molecular interactions, leading to enhanced nerve sensitivity and photophobia," explained study lead Huang Zhuoan. Blocking NEAT1 or TRPM3 activity in mice significantly reduced their light sensitivity, highlighting potential therapeutic targets.

Dr. Minyan Wang, who led the study, emphasized that this chain reaction—a molecule affecting a microRNA, which then influences gene activity linked to pain—could explain how migraines cause light sensitivity. "This is the first evidence showing how a specific long noncoding RNA can augment photophobia in migraines," she noted.

While promising, the study was conducted exclusively in male mice; given that migraines are more prevalent among women, further research is necessary to explore these findings in humans and female subjects. Nonetheless, this discovery opens new avenues for targeted treatments aimed at alleviating migraine-associated photophobia, potentially improving quality of life for many sufferers.

Source: https://medicalxpress.com/news/2025-05-brain-molecule-insights-migraine-sensitivity.html