Effect of catalpol on inflammatory response in rats with Aspergillus fumigatus keratitis by regulating the HMGB1/TLR4 signaling pathway
SUI Shuangshuang
LI Ruidong
YANG Yuan
Abstract：Objective To investigate the effect of catalpol(CAT)on the inflammatory response in rats with Aspergillus fumigatus keratitis(AFK)by regulating the high mobility group protein 1(HMGB1)/Toll-like receptor 4(TLR4)signaling pathway.Methods A total of 60 rats were randomly divided into control group,AFK group,low-dose,medium-dose and high-dose CAT groups,and recombinant HMGB1(rHMGB1)group,with 10 rats in each group.The AFK rat model was constructed.Rats in each group were clinically scored.The hematoxylin and eosin(H&E)staining was applied to observe corneal pathological changes.The activity of myeloperoxidase(MPO)was measured using a commercial kit.Enzyme-linked immunosorbent assay(ELISA)was applied to detect relative levels of interleukin-12(IL-12),tumor necrosis factor alpha(TNF-α),and IL-6.Colony formation assay was applied to measure corneal fungal load.Immunofluorescence was applied to detect neutrophil recruitment.Western blot was applied to detect the protein expressions of HMGB1 and TLR4.Results Compared with those of the control group,rats in AFK group presented an impaired corneal epithelial structure,severe corneal edema,and significantly higher clinical scores,MPO activity,relative levels of IL-12,TNF-α,and IL-6,fungal colony count,neutrophil-positive area,and protein expressions of HMGB1 and TLR4(P＜0.05).Compared with those of the AFK group,rats in the low-dose,medium-dose and high-dose CAT groups had restored corneal tissue structure,and significantly lower clinical scores,MPO activity,relative levels of IL-12,TNF-α,and IL-6,fungal colony count,neutrophil-positive area,and protein expressions of HMGB1 and TLR4(P＜0.05).Compared with the high-dose CAT group,the corneal tissue edema and severity were aggravated in the rHMGB1 group,and clinical scores,MPO activity,relative levels of IL-12,TNF-α,and IL-6,fungal colony count,neutrophil-positive area,and protein expressions of HMGB1 and TLR4 were significantly higher(P＜0.05).Conclusion CAT can inhibit inflammation in AFK rats,and reduce fungal and neutrophil recruitment by inhibiting the HMGB1/TLR4 signaling pathway.
Keywords：Aspergillus fumigatus keratitisinflammatory responsecatalpolhigh mobility group protein 1Toll-like receptor 4
Publication Date：2025-06-26
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：5( 914-918 )