Lonicerae Japonicae Flos Attenuates Neutrophilic Inflammation by Inhibiting Oxidative Stress

• Published in: Antioxidants 2022-09, Vol.11 (9), p.1781
• Main Authors: Lai, Kuei-Hung, Chen, Yu-Li, Lin, Mei-Fang, El-Shazly, Mohamed, Chang, Yu-Chia, Chen, Po-Jen, Su, Chun-Han, Chiu, Yen-Chun, Illias, Amina M, Chen, Chih-Chuan, Chen, Lo-Yun, Hwang, Tsong-Long
• Format: Article
• Language: English
• Subjects: AKT protein; Angiotensin; Anti-inflammatory agents; Autoimmune diseases; bioassay-coupled chromatographic profile; Bioassays; calcium mobilization; CD11b antigen; Cell adhesion; Chlorogenic acid; Chromatography; Chronic obstructive pulmonary disease; Coronaviruses; COVID-19; Dietary supplements; Ethanol; Formyl peptides; Health care; Heat; human neutrophils; Inflammation; Kinases; Leukocyte migration; Leukocytes (neutrophilic); Lonicerae japonicae flos; Mortality; Neutrophils; Oxidative stress; Peptidyl-dipeptidase A; Phenylalanine; Phosphorylation; Reactive oxygen species; SARS-CoV-2-Spike/ACE2; Severe acute respiratory syndrome coronavirus 2; Spike protein; superoxide anion (O2•−); Superoxide anions; Thirst
• ISSN: 2076-3921; 2076-3921
• DOI: 10.3390/antiox11091781

Lonicerae japonicae flos (LJ) is an Asian traditional herb that is used as a dietary supplement, tea, and beverage to clear heat and quench thirst. However, no studies investigated its effect on activated human neutrophils, which played a crucial role in the bad prognosis of coronavirus disease of 2019 (COVID-19) patients by aggravating lung inflammation and respiratory failure. Herein, we evaluated the anti-inflammatory effect of LJ ethanol extract (LJEE) on human neutrophils activated by N-formyl-methionyl-leucyl-phenylalanine (fMLF). Our experimental results indicated that LJEE suppressed fMLF-activated superoxide anion (O2•−) generation, the expression of CD11b, and cell adhesion and migration, as well as the formation of neutrophil extracellular traps in human neutrophils. Further in-depth mechanical investigation revealed that pretreatment with LJEE accelerated the Ca2+ clearance, but did not affect the phosphorylation of mitogen-activated protein kinases (MAPKs) and protein kinase B (Akt) in activated human neutrophils. In addition, LJEE displayed a dose-dependent reactive oxygen species (ROS) scavenger activity, which assisted its anti-inflammatory activity. From the bioassay-coupled chromatographic profile, chlorogenic acids were found to dominate the anti-inflammatory effects of LJEE. Moreover, LJ water extract (LJWE) demonstrated an interrupting effect on the severe acute respiratory syndrome coronavirus-2 spike protein (SARS-CoV-2-Spike)/angiotensin-converting enzyme 2 (ACE2) binding. In conclusion, the obtained results not only supported the traditional use of LJ for heat-clearance, but also suggested its potential application in daily health care during the COVID-19 pandemic.