Contents lists available at ScienceDirect Free Radical Biology and Medicine journal homepage: www.elsevier.com/locate/freeradbiomed Original article Resveratrol suppresses neutrophil activation via inhibition of Src family kinases to attenuate lung injury Yung-Fong Tsai a,b,1 , Chun-Yu Chen a,b,1 , Wen-Yi Chang a , Yu-Ting Syu a , Tsong-Long Hwang a,b,c,d,e,∗ a Graduate Institute of Natural Products, College of Medicine, Chang Gung University, Taoyuan, 333, Taiwan b Department of Anesthesiology, Chang Gung Memorial Hospital, Taoyuan, 333, Taiwan c Chinese Herbal Medicine Research Team, Healthy Aging Research Center, Chang Gung University, Taoyuan, 333, Taiwan d Research Center for Chinese Herbal Medicine, Research Center for Food and Cosmetic Safety, and Graduate Institute of Health Industry Technology, College of Human Ecology, Chang Gung University of Science and Technology, Taoyuan, 333, Taiwan e Department of Chemical Engineering, Ming Chi University of Technology, New Taipei City, 243, Taiwan ARTICLEINFO Keywords: Resveratrol Superoxide anion Reactive oxygen species Lung injury Neutrophil Src family kinase ABSTRACT The natural stilbenoid, Resveratrol (RSV; 3,5,4′-trihydroxystilbene) has been shown to have benefcial efects on infammatory diseases as well as cancer, neurodegenerative diseases, and cardiovascular disorders. The underlying mechanism by which RSV afects neutrophil activation has yet to be fully elucidated. In this study, we tested the hypothesis that RSV modulates the infammatory activities of formyl-Met-Leu-Phe-stimulated human neutrophils. We employed a well-established isolated-neutrophil model to investigate the efects of RSV on neutrophil functions and the underlying mechanism of signaling transduction. The lipopolysaccharide-induced ALI murine model was em- ployed to evaluate the therapeutic efects of RSV. Experiment results demonstrate that RSV reduces respiratory burst, degranulation, integrin expression, and cell adhesion in activated neutrophils in dose-dependent manners. RSV in- hibited phosphorylation of Src family kinases (SFKs) and reduced their enzymatic activities. Moreover, RSV and a selective inhibitor of SFKs (PP2) reduced the phosphorylation of Bruton's tyrosine kinase and Vav. There results indicated that the inhibitory efects of RSV are mediated through the inhibition of the SFKs-Btk-Vav pathway. This study also revealed that RSV attenuates endotoxin-induced lung injury. We surmise that the therapeutic efects of RSV on ALI may derive from its anti-neutrophilic infammation function and free radical-scavenging efects. 1. Introduction Resveratrol (RSV; 3,5,4′-trihydroxystilbene) is a natural stilbenoid found in a variety of foods, such as grapes, red wine, and berries. Studies have reported that RSV has benefcial efects on infammatory diseases, neurodegenerative diseases, cardiovascular diseases, and cancer [1]. The positive efects of RSV can be primarily attributed to its anti-infammatory and antioxidant properties. Moreover, it has also been associated with the regulation of various immune-associated cells and pathways. For example, RSV has been shown to inhibit cyclooxygenase activity both in vitro and in vivo [1,2], block NF-κB transcriptional activity [3,4], inhibit mitogen-ac- tivated protein kinase (MAPK) activity, decrease the production of nitric oxide, and also inhibit the production of pro-infammatory cytokines [5–7] and matrix metallopeptidases [3,8,9]. In a previous study, we showed that RSV attenuates cardiac injury in rats subjected to hemorrhagic shock via an Akt-dependent pathway [10]. RSV has also been reported to inhibit respiratory bursts in human neutrophils and nitric oxide production in macrophages [11]. Nevertheless, the underlying mechanisms by which RSV afects neutrophil activation have yet to be fully elucidated. Researchers have developed numerous therapeutic strategies for the treatment of acute lung injury (ALI); however, it remains one of the most frequent cause of mortality among critically ill patients. A variety of etiologies can lead to ALI, including infection, sepsis, blood trans- fusion, hemorrhagic shock, burn injury, chemical inhalation, and ven- tilator-associated lung injury. The condition is characterized by severe infammatory responses of the lung and infltration of activated im- mune cells. Neutrophils, the most abundant professional phagocytes, make a major contribution to the process of ALI [12–15]. Activated https://doi.org/10.1016/j.freeradbiomed.2019.09.021 Received 9 August 2019; Received in revised form 18 September 2019; Accepted 20 September 2019 ∗ Corresponding author. Graduate Institute of Natural Products, College of Medicine, Chang Gung University, 259 Wenhwa 1st Road, Kweishan, Taoyuan, 333, Taiwan. E-mail address: htl@mail.cgu.edu.tw (T.-L. Hwang). 1 These authors contributed equally to this work. Free Radical Biology and Medicine 145 (2019) 67–77 Available online 21 September 2019 0891-5849/ © 2019 Elsevier Inc. All rights reserved. T