The aim of this study was to assess the anti-inflammatory and anti-apoptotic effects of KIOM-2015EW, the hot-water extract of maple leaves in hyperosmolar stress (HOS)-induced human corneal epithelial cells (HCECs). HCECs were exposed to hyperosmolar medium and exposed to KIOM-2015EW with or without the hyperosmolar media. Tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6 production and apoptosis were observed, and the activation of mitogen-activated protein kinases (MAPKs) including extracellular signal regulated kinase (ERK), p38 and c-JUN N-terminal kinase (JNK) signaling and nuclear factor (NF)-κB was confirmed. Compared to isomolar medium, the induction of cell cytotoxicity significantly increased in HCECs exposed to hyperosmolar medium in a time-dependent manner. KIOM-2015EW-treatment significantly reduced the mRNA and protein expression of pro-inflammatory mediators and apoptosis. KIOM-2015EW-treatment inhibited HOS-induced MAPK signaling activation. Additionally, the HOS-induced increase in NF-κB phosphorylation was attenuated by KIOM-2015EW. The results demonstrated that KIOM-2015EW protects the ocular surface by suppressing inflammation in dry eye disease, and suggest that KIOM-2015EW may be used to treat several ocular surface diseases where inflammation plays a key role.
Keywords: anti-apoptosis; anti-inflammation; dry eye; human corneal epithelial cells; hyperosmolar stress; isoorientin; natural substance; orientin; vitexin.