Immortalized Rat Retinal Capillary Endothelial Cells-SV40

The Anti-Inflammatory Effects of L-DOPA/DA in EAU Gnat1^rd17 Mice Are Mediated by the Suppression of NF-κB (p65) and STAT3 Activity in Retinal Endothelial Cells

The gateway reflex regulates immune cell entry into tissues via neural inputs. Here, Stofkova et al. hypothesized that rod photoreceptor dysfunction in Gnat1rd17 mice remodels retinal neural activity, influencing the blood-retinal barrier and EAU development.

They used transcriptome profiling, target identification, and functional validation to investigate retinal remodeling and its effects on EAU. Results showed that Gnat1rd17 mice exhibited altered retinal dopaminergic systems, leading to exacerbated EAU, which was mitigated by dopamine replacement with L-DOPA. Then, they explored the impact of DA on pro-inflammatory cytokine (IL-6, sIL-6R, and IL-17A)-induced p-p65 and p-STAT3 expression in rat retinal capillary endothelial cells. DA pretreatment significantly decreased nuclear p-p65 and p-STAT3 levels in a dose-dependent manner (Fig. 1a-c), with increased cytoplasmic expression (Fig. 1a, d, e). DA also reduced nuclear p-STAT3 expression under basal conditions, without cytokine stimulation (Fig. 1a, c). Since NF-κB and STAT3 activate pro-inflammatory genes that recruit CD4+ T cells in the retina, we evaluated mRNA expression of IL-6 and T-cell-attracting chemokines (Ccl20, Ccl2, and Cxcl10) under basal and cytokine-stimulated conditions in DA-pretreated cells. DA reduced mRNA expression of IL-6 and all measured chemokines in cytokine-stimulated cells (Fig. 1f). Under basal conditions, DA pretreatment trended towards inhibiting IL-6 and chemokine expression, with significant suppression of Ccl20 and Cxcl10 (Fig. 1f). Overall, these findings demonstrate that L-DOPA/DA mitigates EAU by reducing NF-κB (p65) and STAT3 activation and expression of pro-inflammatory target genes in retinal endothelial cells, thereby protecting the BRB from inflammatory damage.