Acupuncture modulates development of myopia by reducing NLRP3 inflammasome activation via the dopamine-D1R signaling pathway.

Background: Dopamine has been suggested to be a stop signal for eye growth and affects the development of myopia. Acupuncture is known to increase dopamine secretion and is widely used to treat myopia clinically.

Objective: The aim of this study was to determine if acupuncture inhibits myopia progression in form deprived Syrian hamsters by inducing rises in dopamine content that in turn suppress inflammasome activation.

Methods: Acupuncture was applied at LI4 and every other day for 21 days. The levels of molecules associated with the dopamine signaling pathway, inflammatory signaling pathway and inflammasome activation were determined. A dopamine agonist (apomorphine) was used to evaluate if activation of the dopaminergic signaling pathway suppresses myopia progression by inhibiting inflammasome activation in primary retinal pigment epithelial (RPE) cells. A dopamine receptor 1 (D1R) inhibitor (SCH39166) was also administered to the hamsters.

Results: Acupuncture inhibited myopia development by increasing dopamine levels and activating the D1R signaling pathway. Furthermore, we also demonstrated that nucleotide-binding oligomerization domain (NOD)-, leucine-rich repeat (LRR)- and pyrin domain-containing protein 3 (NLR) family pyrin domain-containing 3 (NLRP3) inflammasome activation was inhibited by activation of the D1R signaling pathway.

Conclusion: Our findings suggest that acupuncture inhibits myopia development by suppressing inflammation, which is initiated by activation of the dopamine-D1R signaling pathway.