Inhibiting effect of LIPUS on epithelial-mesenchymal transition in lens epithelial cells

Abstract

To investigate the effect of low-intensity pulsed ultrasound (LIPUS) on epithelial-mesenchymal transition (EMT) in lens epithelial cells. EMT was induced using high glucose (HG) in SRA01/04 cells. Optimal parameters for LIPUS irradiation were determined by cell counting kit-8 assays and flow cytometry. Cell morphology was assessed by light microscopy, while cell migration ability was analyzed by a wound healing assay. Levels of specific proteins and the relationship between autophagy and the cytoskeleton were examined by immunofluorescence (IF) staining and Western blot (WB). Cytoskeletal structures were visualized by phalloidin staining and autophagosomes were quantified by transmission electron microscopy. EMT was successfully induced by HG treatment. Compared to the model group, LIPUS irradiation resulted in a change in cell morphology from spindle to oval, a significant decrease in cell migration area, and an increase in E-cadherin and LC3B/LC3A levels. In contrast, α-SMA and SQSTM1/P62 levels decreased, the number of autophagosomes increased and F-actin levels decreased in the LIPUS group. SRA01/04 cells treated with LIPUS irradiation after autophagy inhibitors 3-MA and CQ showed increased cell migration area compared to the 3-MA/CQ group; LC3B/LC3A levels decreased; SQSTM1/P62 and F-actin levels increased in the LIPUS + 3-MA/CQ group compared to 3-MA/CQ treatment alone. Colocalization of the cytoskeletal marker Arpc2 with the autophagy marker SQSTM1/P62 was also observed. After treatment with the cytoskeletal inhibitor CK666+LIPUS combination therapy, SQSTM1/P62 levels increased while LC3B/LC3A levels decreased. LIPUS inhibited HG-induced EMT by restoring autophagy, which appears to be associated with cytoskeletal remodeling.