Inflammatory cytokine expression on the ocular surface in the Botulium toxin B induced murine dry eye model

[摘要] Purpose: Inflammation plays an importantrole in dry eye syndrome. In this study, inflammatory cytokineexpression on the ocular surface in the Botulium toxin B (BTX-B)induced mouse dry eye model was investigated. Methods: CBA/J mice received aninjection of saline or 20 milliunits (mU) of BTX-B into the lacrimalgland. Tear production and corneal fluorescein staining were evaluatedin all groups before injection and at 3 time points after. Thepro-inflammatory cytokines macrophage inhibitory factor (MIF),interleukin-1β (IL-1 β), tumor necrosis factor-α (TNF- α) andinterleukin-6 (IL-6) in conjunctival and corneal epithelium wereevaluated by real time quantitative PCR and immunohistochemistry. Results: BTX-B injected mice showedsignificantly decreased aqueous tear production and increased cornealfluorescein staining at the 1 week and 2 week time points compared withnormal control and saline-injected mice. The BTX-B injected mice mRNAexpression levels of TNF-α and IL-1β from conjunctivaland corneal epithelial cells increased significantly at two early timepoints comparing with that of normal and saline injected mice, but IL-1βreturned to normal levels at the 4 week time point. Saline injectedmice showed no difference in mRNA expression of TNF-α, IL-1β,MIF, and IL-6 on the ocular surface tissue at all timepoints. Immunohistochemistry confirmed these findings. Conclusions: BTX-B induced mouse modelshowed decreased aqueous tear production, increased corneal fluoresceinstaining, and TNF-α and IL-1β increased expression onthe ocular surface within one month. The patterns seen appeared tomimic those in humans with non-Sjögren’s syndrome keratoconjunctivitissicca (NS-KCS).

[学科分类] 生物化学/生物物理