摘要
AIM:To analyze the impact of calcitonin gene-related peptide(CGRP)in mouse keratitis after Aspergillus fumigatus(A.fumigatus)infection.METHODS:C57 BL/6 mice were treated subconjunctivally with different concentrations of exogenous CGRP,and BALB/c mice were treated with CGRP8-37(a CGRP antagonist)before corneas were infected with A.fumigatus.The cornea was assessed under the slit-lamp and the clinical score was recorded.The mRNA levels of IL-1β,TNF-α,IL-6,and MIP-2 were detected by quantitative real-time polymerase chain reaction(PCR),while the protein level of IL-1βwas determined by Western blotting.In vitro,RAW264.7 cells were used to investigate NLRP3 and IL-1βexpression induced by A.fumigatus after the pretreatment of exogenous CGRP or CGRP8-37.Cytokines expression in RAW264.7 cells was evaluated by real-time PCR and Western blotting.RESULTS:Using exogenous CGRP resulted in downregulated synthesis of IL-1βand MIP-2 stimulated by A.fumigatus in C57 BL/6 mice keratitis,and the synthesis of IL-1β,MIP-2 and IL-6 was up-regulated in BALB/c mice corneas after the pretreatment with CGRP8-37.Pretreatment with exogenous CGRP and CGRP8-37 did not influence TNF-αmRNA levels either in BALB/c or C57 BL/6 mice keratitis.The levels of NLRP3 and IL-1βwere both reduced in A.fumigatus stimulated-macrophages after treatment with exogenous CGRP.And CGRP8-37 pretreatment would increase NLRP3 and IL-1βlevels.CONCLUSION:CGRP may alleviate the inflammatory reaction in mice keratitis after infection with A.fumigatus.The anti-inflammatory effect may be related to the inhibition of NLRP3 expression by CGRP.
基金
Supported by National Natural Science Foundation of China(No.81870632)
the Youth National Natural Science Foundation of China(No.81800800
No.81700800)
the Natural Science Foundation of Shandong Province(No.ZR2017BH025)。