Effects of Total Flavonoids from Exocarpium Citri Grandis on Air Pollution Particle‐Induced Pulmonary Inflammation and Oxidative Stress in Mice

Abstract

Exocarpium Citri Grandis (ECG) is a famous traditional Chinese medicine, which has been commonly used to alleviate cough and phlegm for more than several hundred years, and total flavonoids are the main effective components of this medicine. This study investigated the effects of total flavonoids from ECG (TFECG) on pulmonary inflammation and oxidative stress induced by PM 2.5 in mice. Model mice received an intratracheal instillation of PM 2.5 (10 mg/mL) once at day 0. Bronchoalveolar lavage fluid (BALF) was collected after 72 hr to measure the total number of white blood cell (WBC), neutrophils (NEUT), lymphocytes (LYMPH), and monocytes (MONO). The levels of tumor necrosis factor-α (TNF-α), interleukin 1β (IL-1β), interleukin-6 (IL-6), and interleukin-18 (IL-18) in BALF were quantified by using enzyme-linked immunosorbent assay kits. Lung tissues were used to determine the contents of total protein (TP), malondialdehyde (MDA), nitric oxide (NO), reduced glutathione (GSH), oxidized glutathione (GSSG) and the activities of superoxide dismutase (SOD), lactate dehydrogenase (LDH), Glutathione Peroxidase (GSH-Px), and inducible nitric oxide synthase (iNOS). We found that TFECG significantly inhibited PM 2.5 -stimulated overproduction of TNF-α, IL-1β, IL-6, and IL-18 and increased the numbers of WBC, NEUT, LYMPH, and MONO in BALF. TFECG observably relieved the PM 2.5 -induced increases in the contents of TP, MDA, and NO, and the activities of LDH and iNOS. TFECG also alleviated PM 2.5 -induced decreases in the activities of iNOS and GSH-Px as well as GSH/GSSG ratio. The results indicate that TFECG has anti-inflammatory and antioxidant activities, which may potentially contribute to the treatment of PM 2.5 -induced lung injury.Practical Application: Exocarpium Citri Grandis (ECG) is rich in flavonoids, which are beneficial to improve antiinflammation and antioxidant capacity. We proved that total flavonoids of ECG had a positive therapeutic effect on PM 2.5 -induced lung injury, which expands the potential applications of ECG in the dietary supplement industries.

PM2.5‐induced pulmonary inflammation via activating of the NLRP3/caspase‐1 signaling pathway

“…The data revealed that PM2.5 exposure enhanced the number of leukocytes, neutrophils, macrophages, lymphocytes, and eosinophils compared with the control group and saline group (Figure 1B‐F). Moreover, previous studies have confirmed that PM2.5‐induced oxidative stress appears as an excessive variation of associated‐enzyme activities, oxidant accumulation and so on 17,18 . As expected, ELISA analysis results showed that the levels of TP and LDH in the PM2.5 treatment group were higher than those in the control and saline group (Figure 1G,H).…”

Ecklonia cava Attenuates PM2.5-Induced Cognitive Decline through Mitochondrial Activation and Anti-Inflammatory Effect

“…The accumulated PM 2.5 directly causes pulmonary dysfunction by the systemic oxidative damage and an inflammatory reaction [1]. In lung tissue, PM 2.5 stimulated oxidative stress, inflammation, and DNA damage lead to serious lung damage and airway diseases (e.g., allergic airway inflammation, asthma, and chronic obstructive pulmonary disease) [3].…”

Qianjinweijing Decoction Protects Against Fine Particulate Matter Exposure-mediated Lung Function Disorder

“…The results show that QJWJ significantly reduced the incidence of RVD, compared with the placebo group. PM 2.5 exposure was a critical factor in lung function impairment via oxidative stress and inflammation (He et al, 2017;Yue et al, 2019;Zhu et al, 2019), accompanied with activation of alveolar macrophages (Jia et al, 2021). Hence, anti-oxidative and anti-inflammatory herbs of natural origin may be an effective and safe approach to alleviate the adverse effects of PM 2.5 pollution on the lung.…”