Dataset Information

Inhibition of LOX-1 alleviates the proinflammatory effects of high-mobility group box 1 in Aspergillus fumigatus keratitis.

ABSTRACT:

Aim

To investigate the inflammatory amplification effect of high-mobility group box 1 (HMGB1) in Aspergillus fumigatus (A. fumigatus) keratitis and the relationship between lectin-like oxidized low-density lipoprotein receptor 1 (LOX-1) and HMGB1 in keratitis immune responses.

Methods

Phosphate buffer saline (PBS), and Boxb were injected into BALB/c mice subconjunctivally before the corneas were infected with A. fumigatus. RAW264.7 macrophages and neutrophils were pretreated with PBS and Boxb to determine the HMGB1 inflammatory amplification effects. Abdominal cavity extracted macrophages were pretreated with Boxb and Poly (I) (a LOX-1 inhibitor) before A. fumigatus hyphae stimulation to prove the the relationship between the two molecules. LOX-1, interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), macrophage inflammatory protein-2 (MIP-2) and IL-10 were assessed by polymerase chain reaction and Western blot.

Results

Pretreatment with Boxb exacerbated corneal inflammation. In macrophages and neutrophils, A. fumigatus induced LOX-1, IL-1β, TNF-α and MIP-2 expression in Boxb group was higher than those in PBS group. Poly (I) treatments before infection alleviated the proinflammatory effects of Boxb in abdominal cavity extracted macrophages. Pretreatment with Boxb did not influence Dectin-1 mRNA levels in macrophages and neutrophils.

Conclusion

In fungal keratitis, HMGB1 is a proinflammatory factor in the first line of immune response. HMGB1 mainly stimulates neutrophils and macrophages to produce inflammatory cytokines and chemokines during the immune response. LOX-1 participates in HMGB1 induced inflammatory exacerbation in A. fumigatus keratitis.

SUBMITTER: Jiang JQ

PROVIDER: S-EPMC6580210 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

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Publications

Inhibition of LOX-1 alleviates the proinflammatory effects of high-mobility group box 1 in <i>Aspergillus fumigatus</i> keratitis.

Jiang Jia-Qian JQ Li Cui C Cui Cong-Xian CX Ma Yu-Na YN Zhao Gui-Qiu GQ Peng Xu-Dong XD Xu Qiang Q Wang Qian Q Zhu Guo-Qiang GQ Li Chen-Yu CY

International journal of ophthalmology 20190618 6

<h4>Aim</h4>To investigate the inflammatory amplification effect of high-mobility group box 1 (HMGB1) in <i>Aspergillus fumigatus</i> (<i>A. fumigatus</i>) keratitis and the relationship between lectin-like oxidized low-density lipoprotein receptor 1 (LOX-1) and HMGB1 in keratitis immune responses.<h4>Methods</h4>Phosphate buffer saline (PBS), and Boxb were injected into BALB/c mice subconjunctivally before the corneas were infected with <i>A. fumigatus.</i> RAW264.7 macrophages and neutrophils ...[more]

PMID: 31236343

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