Sodium butyrate alleviates lipopolysaccharide-induced inflammation through JAK/STAT signalling in primary human corneal fibroblasts

Background

Bacterial keratitis is a common cause of blindness. Antibiotic treatment leads to the rapid release of lipopolysaccharide (LPS), which can activate corneal fibroblasts and cause persistent and excessive inflammatory responses. The anti-inflammatory drugs currently used to treat keratitis have serious side effects. Therefore, the ability of sodium butyrate (NaB), which can suppress the production of proinflammatory cytokines and promote the production of anti-inflammatory cytokines, to ameliorate keratitis was assessed in the present study.

Methods

The effect of NaB on the viability of primary human corneal fibroblasts was assayed with a CCK-8 kit. Cell migration was assessed by an in vitro scratch assay. Cell phenotypes were assessed by Western blotting and immunofluorescence staining. An antibody array was used to measure the production of proinflammatory cytokines and chemokines.

Results

At 0–1 mM, NaB had no significant effect on cell viability, promoted the expression of the keratocyte marker keratocan and inhibited the fibroblast marker vimentin. Inhibition of cell migration was observed in the wound healing assay. By targeting the Janus kinase/signal transducer and activator of transcription (JAK/STAT) signalling pathway, NaB decreased the levels of inflammation-related cytokines and chemokines whose expression was induced by LPS.

Conclusions

NaB maintained the keratocyte phenotype, inhibited cell migration, and relieved LPS-induced inflammatory responses through the JAK/STAT signalling pathway.