Abstract
OBJECTIVE: To determine the mechanism of electro-acupuncture (EA) effect by the wingless-related integration site (Wnt)/β-catenin pathway in the guinea pig myopia model. METHODS: Following myopia induction and EA, guinea pigs were treated with biometry to evaluate refraction and axial length. Hematoxylin and eosin (HE) staining was used to observe that the retina, choroid, and sclera had abnormal morphology. At 4, 6, and 8 weeks, quantitative polymerase chain reaction (qPCR) was used to identify the expression of matrix metallopeptidase-2 (MMP-2)/MMP-3/tissue inhibitor of metalloprotease-2 (TIMP-2)/TIMP-3/Wnt family member 2B (WNT2B)/WNT3A/ WNT7B/beta-catenin 1 (CTNNB1), and dickkopf wnt signaling pathway inhibitor 1 (DKK-1) mRNAs in the retina, choroid, and sclera. Western blot was used to detect the protein expression of WNT7B/2B/3A, CTNNB1 and DKK-1 in retina, choroid and sclera at 4 weeks. Enzyme-linked immunosorbent assay was used to detect the protein expression of MMP-2/TIMP-2 and MMP-3/TIMP-3 in serum at 4 weeks. Moreover, a DKK-1 inhibitor was injected into the vitreous cavity, and the expression of the above molecules was detected. RESULTS: EA could reduce the optic axial length and diopter and ameliorate ocular pathology, inhibited the expression of MMP-2/MMP-3 and WNT2B/WNT3A/ WNT7B/CTNNB1, while increased the expression levels of TIMP-2/TIMP-3 and DKK-1. However, the expression levels of WNT2B/WNT3A/WNT7B/CTNNB1 and MMP-2/MMP-3 were significantly increased, and the TIMP-2/TIMP-3 and DKK-1 expression levels were decreased after injected DKK-1 inhibitor. CONCLUSION: The mechanism of EA's effects on myopia may involve the downregulation of the Wnt/β-catenin pathway and correct MMP-2/MMP-3/TIMP-2/TIMP-3 balance.