Taurine inhibits interleukin-6 expression and release induced by ultraviolet B exposure to human retinal pigment epithelium cells

Abstract

Background: The massive uptake of compatible osmolytes is a self-protective response shared by retina exposed to hypertonic stress and ultraviolet stress.Objective: This study aimed to investigate the protective effects of taurine against ultraviolet damage in human retinal pigment epithelium cells.Methods: Real-time PCR, radioimmunoassay, ELISA and immunoassay were used to measure osmolyte uptake and IL-6 expression.Results: Compared with normotonic stress, hypertonic stress led to an induction of osmolyte uptake including betaine, myoinositol and taurine. UVB exposure upregulated osmolyte transporter mRNA expression and increased osmolyte uptake respectively. Especially, taurine suppressed UVB-induced IL-6 mRNA expression significantly. The accumulation of IL-6 in UVB-exposed human retinal pigment epithelial cells supernatant was much slower when the cells were preincubated with taurine. Moreover, taurine suppressed IL-6 concentration in aqueous humour.Conclusion: The effect of compatible osmolyte taurine on IL-6 expression and release may play an important role in cell resistance and adaption to UVB exposure.