Bletinib ameliorates neutrophilic inflammation and lung injury by inhibiting Src family kinase phosphorylation and activity

Ting-I Kao; Po-Jen Chen; Yi-Hsuan Wang; Hsin-Hui Tseng; Shih-Hsin Chang; Tian-Shung Wu; Sien-Hung Yang; Yen-Tung Lee; Tsong-Long Hwang

doi:10.1111/bph.15597

Bletinib ameliorates neutrophilic inflammation and lung injury by inhibiting Src family kinase phosphorylation and activity

Br J Pharmacol. 2021 Oct;178(20):4069-4084. doi: 10.1111/bph.15597. Epub 2021 Jul 14.

Authors

Ting-I Kao^{1

2

3}, Po-Jen Chen⁴, Yi-Hsuan Wang¹, Hsin-Hui Tseng¹, Shih-Hsin Chang^{1

5}, Tian-Shung Wu⁶, Sien-Hung Yang^{2

3

5}, Yen-Tung Lee^{1

7

8}, Tsong-Long Hwang^{1

3

5

9

10}

Affiliations

¹ Graduate Institute of Biomedical Sciences and Graduate Institute of Natural Products, College of Medicine, Chang Gung University, Taoyuan, Taiwan.
² Division of Chinese Internal Medicine, Department of Traditional Chinese Medicine, Chang Gung Memorial Hospital, Taoyuan, Taiwan.
³ School of Traditional Chinese Medicine, College of Medicine, Chang Gung University, Taoyuan, Taiwan.
⁴ Department of Cosmetic Science, Providence University, Taichung, Taiwan.
⁵ Research Center for Chinese Herbal Medicine and Graduate Institute of Health Industry Technology, College of Human Ecology, Chang Gung University of Science and Technology, Taoyuan, Taiwan.
⁶ Department of Chemistry, National Cheng Kung University, Tainan, Taiwan.
⁷ Department of Cosmetic Science, College of Human Ecology, Chang Gung University of Science and Technology, Taoyuan, Taiwan.
⁸ Department of Chinese Medicine, MacKay Memorial Hospital, Taipei, Taiwan.
⁹ Department of Anesthesiology, Chang Gung Memorial Hospital, Taoyuan, Taiwan.
¹⁰ Department of Chemical Engineering, Ming Chi University of Technology, New Taipei City, Taiwan.

Abstract

Background and purpose: Neutrophil overactivation is crucial in the pathogenesis of acute lung injury (ALI). Bletinib (3,3'-dihydroxy-2',6'-bis(p-hydroxybenzyl)-5-methoxybibenzyl), a natural bibenzyl, extracted from the Bletilla plant, exhibits anti-inflammatory, antibacterial, and antimitotic effects. In this study, we evaluated the therapeutic effects of bletinib in human neutrophilic inflammation and LPS-mediated ALI in mice.

Experimental approach: In human neutrophils activated with the formyl peptide (fMLP), we assessed integrin expression, superoxide anion production, degranulation, neutrophil extracellular trap (NET) formation, and adhesion through flow cytometry, spectrophotometry, and immunofluorescence microscopy. Immunoblotting was used to measure phosphorylation of Src family kinases (SFKs) and downstream proteins. Finally, a LPS-induced ALI model in male BALB/c mice was used to investigate the potential therapeutic effects of bletinib treatment.

Key results: In activated human neutrophils, bletinib reduced degranulation, respiratory burst, NET formation, adhesion, migration, and integrin expression; suppressed the enzymic activity of SFKs, including Src, Lyn, Fgr, and Hck; and inhibited the phosphorylation of SFKs as well as Vav and Bruton's tyrosine kinase (Btk). In mice with ALI, the pulmonary sections demonstrated considerable amelioration of prominent inflammatory changes, such as haemorrhage, pulmonary oedema, and neutrophil infiltration, after bletinib treatment.

Conclusion and implications: Bletinib regulates neutrophilic inflammation by inhibiting the SFK-Btk-Vav pathway. Bletinib ameliorates LPS-induced ALI in mice. Further biochemical optimisation of bletinib may be a promising strategy for the development of novel therapeutic agents for inflammatory diseases.

Keywords: Src family kinase; acute lung injury; acute respiratory distress syndrome; bletinib; inflammation; neutrophil.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Acute Lung Injury* / chemically induced
Acute Lung Injury* / drug therapy
Animals
Inflammation
Male
Mice
Mice, Inbred BALB C
Phosphorylation
src-Family Kinases* / metabolism

Substances

src-Family Kinases