Electroacupuncture inhibits the corneal ROS/TXNIP/NLRP3 signaling pathway in a rat model of dry eye syndrome.

Abstract

Electroacupuncture (EA) treatment has been found to ameliorate clinical symptoms in patients with dry eye, but its mechanisms are still not entirely clear. To study the regulation of EA on ocular surface function and the corneal reactive oxygen species (ROS)/thioredoxin-interacting protein (TXNIP)/Nod-like receptor protein 3 (NLRP3) inflammatory signaling pathway in dry eye syndrome (DES) model rats. Male Sprague-Dawley (SD) rats were randomly divided into five groups: Normal, Model, Model + EA, Model + NAC (N-actetylcysteine) and Model + NS (normal saline). The DES model was developed by subcutaneous injection of scopolamine hydrobromide with exposure to an air draft in the latter four groups. After intervention, the Schirmer I test (SIT), tear film break-up time (BUT) and ROS content were measured, the histopathological changes of corneal tissues were observed, and the mRNA and protein expression levels of TXNIP, NLRP3, apoptosis-associated Speck-like protein containing CARD (ASC), caspase-1, interleukin (IL)-1β and IL-18 were detected. Compared with the Model group, the SIT and BUT increased significantly in the Model + EA group after intervention (p < 0.05), and the corneal injury was improved. Corneal ROS content declined in both Model + EA and Model + NAC groups (p < 0.05), and mRNA expression of TXNIP, NLRP3, ASC and caspase-1 also decreased (p < 0.01). Corneal protein expression of TXNIP, NLRP3, IL-1β and IL-18 decreased significantly in the Model + EA group (p < 0.01). Inhibiting the ROS/TXNIP/NLRP3 signaling pathway may be the mechanism underlying the role of EA in improving corneal injury in DES model rats.