Morita-Baylis-Hillman adduct 2-(3-hydroxy-2-oxoindolin-3-yl)acrylonitrile (ISACN) modulates the inflammatory process during LPS-induced acute lung injury

Abstract

Background

Despite its homeostatic role, inflammation is involved in several pathologies, such as acute lung injury. Morita-Ballys-Hilman adducts (MBHA) are a group of synthetic molecules and present a wide range of biological activities, including anti-inflammatory action. Thus, this study aimed to assess whether ISACN, an MBHA, modulates inflammation during acute lung injury induced by lipopolysaccharide (LPS).

Methods

BALB/c mice were intraperitoneally treated with 24 mg/kg ISACN and challenged with LPS (2.5 mg/kg). On bronchoalveolar lavage fluid (BALF), we assessed the total and differential leukocyte count and measurement of protein leakage, cytokines (IL-1β, IL-6, and TNF-α), and chemokine (CXCL-1). Additionally, lung histopathology was also performed (H&E staining). In vitro studies were conducted with peritoneal macrophages to assess the possible mechanism of action. They were cultured in the presence of ISACN (5 and 10 µM) and stimulated by LPS (1 µg/mL).

Results

ISACN reduced neutrophil migration, protein leakage, and inflammatory cytokines (IL-1β, IL-6, and TNF-α) without interfering with the production of CXCL1. In addition, ISACN caused a decrease in LPS-induced lung injury as evident from histopathological changes. In peritoneal macrophages, ISACN diminishes the nitric oxide and cytokine levels (IL-1β, IL-6, and TNF-α). The treatment with ISACN (10 μM) also reduced LPS-induced TLR4, CD69, iNOS overexpression, and the LPS-induced ERK, JNK, and p38 phosphorylation.

Conclusion

Thus, this work showed for the first time the immunomodulatory action of MBHA in LPS-induced acute lung injury and provided new evidence for the mechanisms related to the anti-inflammatory effect of ISACN.

Keywords:

• ALI
• ARDS
• immunomodulation
• MBHA
• isatin

Author contributions

Conceptualization, JSFS and SR-M; methodology, APL, JSFS, LAAV, CGL-J, DCMC, TRO, RKSM and EAL; formal analysis, APSV, LAAV, CGL-J, JSFS, SR-M; investigation, JSFS, LHAC-S, DCMC, EAL, JMSN, LAMPF, TRO, and RKSM; writing—original draft preparation, JSFS; writing—review and editing, JSFS, LHAC-S, SR-M, LAAV, and CGL-J; supervision, SR-M. All authors have read and agreed to the published version of the manuscript.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request.

Additional information

Funding

This research was funded by Coordenação de Aperfeiçoamento de Pessoal de Nível Superior” (CAPES), and by “Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)”. This work was funded by the Public Call no 03/2020 Produtividade em Pesquisa PROPESQ/PRPG/UFPB PII13125-2020.