Interleukin-6 promotes migration and extracellular matrix synthesis in retinal pigment epithelial cells

Proliferative vitreoretinopathy (PVR) is the most common cause of surgical failure in the rhegmatogenous retinal detachment (RD) treatment. Retinal pigment epithelial (RPE) cell proliferation, migration, and the synthesis of extracellular matrix (ECM) are intrinsic to the formation of a PVR membrane. High level of interleukin-6 (IL-6) has been found in the vitreous of PVR patients, while the role of IL-6 in RPE cells remaining further characterized. In the present study, we evaluated the potential regulatory effects of IL-6 on cell migration, ECM components, and transforming growth factor β2 (TGF-β2) expression in RPE cells. Furthermore, cell counting kit-8 (CCK‑8) assay was used to investigate cell proliferation activity. We found that IL-6 promoted fibronectin (Fn) and type I collagen (COL-1), TGF-β2 expression in RPE cells, also stimulate RPE cell migration effectively. Moreover, the induction of IL-6 activated the Janus kinase/signal transducers and activators of transcription (JAK/STAT3) and the nuclear factor kappa-B (NF-κB) signaling pathways significantly. Simultaneously, both JAK/STAT3 and NF-κB pathways inhibitors, WP1066 and BAY11-7082, alleviated IL-6-induced biological effects, respectively. However, it was noted that IL-6 had little effect on α-smooth muscle actin (α-SMA) expression. Collectively, our results reveal that IL-6 promotes RPE cell migration and ECM synthesis via activating JAK/STAT3 and NF-κB signaling pathways, which may play a crucial role in PVR formation.