<i>Aruncus Dioicus</i> Var. <i>Kamtschaticus</i> Extract Prevents Ocular Endoplasmic Reticulum Stress, Inflammation, and Oxidative Stress <i>In Vitro</i>

The aim of this study was to determine the anti-inflammatory and anti-endoplasmic reticulum (ER) stress effects of <i>Aruncus dioicus</i> var. <i>kamtschaticus</i> (ADK) extract on ARPE-19 cells. Pretreatment with ADK effectively mitigated thapsigargin (Tg)-induced increases in vascular endothelial growth factor protein secretion and intracellular calcium levels. Furthermore, pretreatment with ADK suppressed ocular ER stress-related protein expression in a dose-dependent manner, inhibited the loss of tight junctions, and suppressed interleukin-6 gene expression. Moreover, ADK pretreatment significantly prevented lipopolysaccharide-inducible proinflammatory cytokine gene expression at the transcription level and the phosphorylation of proteins involved in the mitogen-activated protein kinase-nuclear factor kappa-light-chain-enhancer of activated B cells (NF<i>κ</i>B) axis at the posttranslational level. Additionally, ADK extract enhanced antioxidant activity, as evidenced by increased heme oxygenase-1 protein expression and increased 2,2-diphenyl-1-picrylhydrazyl radical scavenging and ferric-reducing antioxidant power. In conclusion, ADK extract effectively protected ARPE-19 cells from ocular ER stress, inflammation, and oxidative stress, demonstrating its potential as a nutraceutical intervention for ocular diseases.