Quercetin protects THP-1 macrophages against cellular stress response induced by Pseudomonas aeruginosa protease LasB
10.3760/cma.j.cn112150-20231215-00451
- VernacularTitle:槲皮素对铜绿假单胞菌LasB诱导THP-1巨噬细胞应激反应的保护作用
- Author:
Yanying REN
1
;
Xinwei LIU
;
Rui ZHU
;
Xiaojuan YOU
;
Dengzhou LI
;
Zhiqiang HE
;
Chunxia WANG
;
Ximing YANG
;
Yongwei LI
Author Information
1. 河南中医药大学第二临床医学院，郑州 450046
- Keywords:
Quercetin;
Macrophages;
Apoptosis;
Inflammation;
Oxidative stress
- From:
Chinese Journal of Preventive Medicine
2024;58(3):337-346
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To investigate the protective effect of quercetin against LasB-induced apoptosis, inflammation, and oxidative stress in THP-1 macrophages, providing valuable insights into the use of quercetin as a virulence inhibitor for Pseudomonas aeruginosa infection treatment. Methods:This was an experimental study. The experimental strain was the standard strain. The LasB protein was obtained utilizing protein recombination technology, while the enzyme activity of LasB was assessed through both the Elastin Congo red assay and fluorescently labelled elastin assay. The LasB-induced THP-1 macrophage infection model was established, and quercetin was utilized for intervention. Cell viability was evaluated via CCK-8 assay, while cell morphology was observed under an inverted microscope. Apoptosis detection involved employing both TUNEL and Annexin V/PI staining. The mRNA expression and protein levels of inflammatory cytokines and COX-2 were determined by RT-qPCR and ELISA respectively. Intracellular ROS levels were quantified using the DCFH-DA fluorescent probe. One-way ANOVA was used for statistical analysis, and Tukey test was used for multiple comparisons. Results:The pLasB with a molecular weight of 33 000 and acceptable enzymatic activity (purity>90%), was successfully obtained. THP-1 macrophages treated with pLasB at a concentration of 100 μg/ml presented significantly decreased viability and integrity rate when compared with the normal control group. Additionally, pLasB promoted apoptosis, up-regulated the levels of inflammatory cytokines IL-1α, IL-1β, IL-6, IL-10, IL-12, and TNF-α, increased intracellular ROS fluorescence intensity, and elevated COX-2 mRNA expression level. Furthermore, the viability of THP-1 macrophages was significantly enhanced under quercetin intervention at concentrations of 2.5 μmol/L, 5 μmol/L and 10 μmol/L. The apoptosis rate exhibited a significant reduction from 18.32%±0.17% to 13.17%±0.20%, 11.43%±0.06% and 7.74%±0.04%, respectively ( F=1 679, P<0.05). There was a notable down-regulation of pro-inflammatory cytokines IL-1α, IL-1β, IL-6, IL-12 and TNF-α while the anti-inflammatory cytokine IL-10 showed a significant up-regulation. Both intracellular ROS fluorescence intensity ( F=86.92, P<0.05) and COX-2 level ( F=24.62, P<0.05) demonstrated a substantial decrease. Conclusion:Quercetin demonstrates significant efficacy in inhibiting LasB-induced apoptosis, inflammation, and oxidative stress in THP-1 macrophages, which highlights immense potential as a potent virulence inhibitor of Pseudomonas aeruginosa.
