TY - JOUR
T1 - Dimethyl fumarate ameliorates fungal keratitis by limiting fungal growth and inhibiting pyroptosis
AU - Gu, Lingwen
AU - Lin, Jing
AU - Wang, Qian
AU - Zhang, Lina
AU - Yin, Min
AU - Lin, Hao
AU - Zheng, Hengrui
AU - Zhao, Guiqiu
AU - Li, Cui
N1 - Publisher Copyright:
© 2023 Elsevier B.V.
PY - 2023/2
Y1 - 2023/2
N2 - Purpose: We aimed to investigate the therapeutic role of dimethyl fumarate (DMF) in fungal keratitis. Methods: Human corneal epithelial cells (HCECs) and mouse models of fungal keratitis were used in this study. The antifungal effect of DMF on Aspergillus fumigatus (A. fumigatus) was confirmed by examining the minimum inhibitory concentration (MIC), biofilm formation, conidial adherence and corneal fungal loads. Slit-lamp photography, haematoxylin and eosin staining and immunostaining were used to assess the severity of corneal impairment. RT-PCR, western blot, ELISA, immunohistochemistry and immunostaining were performed to examine the effects of DMF on the expression of the inflammatory mediators during fungal infection. Results: In vitro, DMF limited A. fumigatus growth, biofilm formation, and conidial adherence and reduced the mRNA levels of AldA, GlkA, GAPDH, HxkA, PgkA, Sdh2, GelA and ChsF in A. fumigatus. In vivo, DMF effectively decreased corneal fungal loads. DMF attenuated corneal inflammatory impairment by suppressing inflammatory cell accumulation and downregulating cytokine expression. DMF notably downregulated the high expression of NLRP3, cleaved GSDMD, cleaved caspase-1, mature IL-1β and mature IL-18 induced by fungi. The production of Nrf2 and HO-1 could be further increased by DMF in infected HCECs. Nrf2 siRNA pretreatment counteracted DMF-mediated downregulation of the expression of the active forms of IL-18, IL-1β, caspase-1 and GSDMD. Conclusion: DMF limits fungal growth by suppressing biofilm formation, conidial adherence and respiratory metabolism. It also exerts an anti-inflammatory effect on fungal keratitis by inhibiting pyroptosis, which could be regulated by Nrf2. Our results suggest that DMF plays a therapeutic role in fungal keratitis.
AB - Purpose: We aimed to investigate the therapeutic role of dimethyl fumarate (DMF) in fungal keratitis. Methods: Human corneal epithelial cells (HCECs) and mouse models of fungal keratitis were used in this study. The antifungal effect of DMF on Aspergillus fumigatus (A. fumigatus) was confirmed by examining the minimum inhibitory concentration (MIC), biofilm formation, conidial adherence and corneal fungal loads. Slit-lamp photography, haematoxylin and eosin staining and immunostaining were used to assess the severity of corneal impairment. RT-PCR, western blot, ELISA, immunohistochemistry and immunostaining were performed to examine the effects of DMF on the expression of the inflammatory mediators during fungal infection. Results: In vitro, DMF limited A. fumigatus growth, biofilm formation, and conidial adherence and reduced the mRNA levels of AldA, GlkA, GAPDH, HxkA, PgkA, Sdh2, GelA and ChsF in A. fumigatus. In vivo, DMF effectively decreased corneal fungal loads. DMF attenuated corneal inflammatory impairment by suppressing inflammatory cell accumulation and downregulating cytokine expression. DMF notably downregulated the high expression of NLRP3, cleaved GSDMD, cleaved caspase-1, mature IL-1β and mature IL-18 induced by fungi. The production of Nrf2 and HO-1 could be further increased by DMF in infected HCECs. Nrf2 siRNA pretreatment counteracted DMF-mediated downregulation of the expression of the active forms of IL-18, IL-1β, caspase-1 and GSDMD. Conclusion: DMF limits fungal growth by suppressing biofilm formation, conidial adherence and respiratory metabolism. It also exerts an anti-inflammatory effect on fungal keratitis by inhibiting pyroptosis, which could be regulated by Nrf2. Our results suggest that DMF plays a therapeutic role in fungal keratitis.
KW - Aspergillus fumigatus
KW - Dimethyl fumarate
KW - Fungal keratitis
KW - Nrf2
KW - Pyroptosis
UR - http://www.scopus.com/inward/record.url?scp=85146158304&partnerID=8YFLogxK
U2 - 10.1016/j.intimp.2023.109721
DO - 10.1016/j.intimp.2023.109721
M3 - Article
C2 - 36641891
AN - SCOPUS:85146158304
SN - 1567-5769
VL - 115
JO - International Immunopharmacology
JF - International Immunopharmacology
M1 - 109721
ER -