Serum of limb remote ischemic postconditioning inhibits fMLP-triggered activation and reactive oxygen species releasing of rat neutrophils

Gangling Chen; Jiangwei Zhang; Mingyue Sheng; Sanli Zhang; Qi Wu; Lei Liu; Boyang Yu; Junping Kou

doi:10.1080/13510002.2021.1982515

Serum of limb remote ischemic postconditioning inhibits fMLP-triggered activation and reactive oxygen species releasing of rat neutrophils

Redox Rep. 2021 Dec;26(1):176-183. doi: 10.1080/13510002.2021.1982515.

Authors

Gangling Chen^{1

2}, Jiangwei Zhang^{1

2}, Mingyue Sheng^{1

2}, Sanli Zhang^{1

2}, Qi Wu³, Lei Liu⁴, Boyang Yu^{1

2}, Junping Kou^{1

2}

Affiliations

¹ Department of Pharmacology of Chinese Materia Medica, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, People's Republic of China.
² State Key Laboratory of Natural Products, Jiangsu Key Laboratory of TCM Evaluation and Translational Research, Department of Chinese Material Medica, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, People's Republic of China.
³ State Key Laboratory of Natural Medicines, Research Department of Pharmacognosy, School of Traditional Chinese Pharmacy, China Pharmaceutical University, Nanjing, People's Republic of China.
⁴ Department of Anesthesiology, Center for Translational Research in Neurodegenerative Disease and McKnight Brain Institute, University of Florida, Gainesville, FL, USA.

Abstract

Objectives: The study explores the protective role of the peripheral serum of limb remote ischemic postconditioning (LRIP) in reducing the reactive oxygen species (ROS) levels and neutrophil activation, which are responsible for the deleterious reperfusion injury.

Methods: LRIP was induced in Sprague-Dawley rats by three cycles of 5 min occlusion /5 min reperfusion on the left hind limb. The blood samples were collected before LRIP or 0 and 1 h after LRIP (named Serum_Sham, Serum_LRIP0, Serum_LRIP1, respectively). The effects of LRIP serum on ROS level and neutrophils activation were determined. The expression of MyD88-TRAF6-MAPKs and PI3K/AKT pathways in neutrophils were examined.

Results: When compared with Serum_Sham, Serum_LRIP0 and Serum_LRIP1 significantly reduced the ROS released from neutrophils activated by fMLP. Meanwhile, the mRNA expression levels of NADPH oxidase subunit p22^phox and multiple ROS-producing related key proteins, such as NADPH oxidase subunit p47^phox ser 304, ser 345. MyD88, p-ERK, p-JNK and p-P38 expression of neutrophils were downregulated by Serum_LRIP0 and Serum_LRIP1. Serum_LRIP1 also downregulated p47^phox mRNA expression and tumor necrosis factor receptor-associated factor 6 (TRAF6) protein expression.

Conclusion: LRIP serum protects against ROS level and neutrophils activation involving the MyD88-TRAF6-MAPKs. This finding provides new insight into the understanding of LRIP mechanisms.

Keywords: MYD88; NADPH; ROS; Reperfusion; fMLP; ischemic postconditioning; neutrophil; oxidative stress.

MeSH terms

Animals
Ischemic Postconditioning*
NADPH Oxidases / genetics
Neutrophils
Phosphatidylinositol 3-Kinases
Rats
Rats, Sprague-Dawley
Reactive Oxygen Species

Substances

Reactive Oxygen Species
NADPH Oxidases

Grants and funding

This study was supported by National Natural Science Foundation of China [grant number 81503284], the “Double First-Class” University project ‘Double First-Class’ University project [grant numbers CPU2018GF06, CPU2018GF07].