Study on Lung Injury Caused by Fine Particulate Matter and Intervention Effect of Rhodiola wallichiana

Therapeutic effects of hederacolchiside A1 on particulate matter-induced pulmonary injury

Particulate matter (PM) comprises a hazardous mixture of inorganic and organic particles that carry health risks. Inhaling fine PM particles with a diameter of ≤2.5 μm (PM2.5) can promote significant lung damage. Hederacolchiside A1 (HA1) exhibits notable in vivo antitumor effects against various solid tumors. However, our understanding of its therapeutic potential for individuals with PM2.5-induced lung injuries remains limited. Here, we explored the protective properties of HA1 against lung damage caused by PM2.5 exposure. HA1 was administered to the mice 30 min after intratracheal tail vein injection of PM2.5. Various parameters, such as changes in lung tissue wet/dry (W/D) weight ratio, total protein/total cell ratio, lymphocyte counts, inflammatory cytokine levels in bronchoalveolar lavage fluid (BALF), vascular permeability, and histology, were assessed in mice exposed to PM2.5. Our data showed that HA1 mitigated lung damage, reduced the W/D weight ratio, and suppressed hyperpermeability caused by PM2.5 exposure. Moreover, HA1 effectively decreased plasma levels of inflammatory cytokines in those exposed to PM2.5, including tumor necrosis factor-α, interleukin-1β, and nitric oxide, while also lowering the total protein concentration in BALF and successfully alleviating PM2.5-induced lymphocytosis. Furthermore, HA1 significantly decreased the expression levels of toll-like receptor 4 (TLR4), myeloid differentiation primary response (MyD) 88, and autophagy-related proteins LC3 II and Beclin 1 but increased the protein phosphorylation of the mammalian target of rapamycin (mTOR). The anti-inflammatory characteristics of HA1 highlights its potential as a promising therapeutic agent for mitigating PM2.5-induced lung injuries by modulating the TLR4-MyD88 and mTOR-autophagy pathways.

Therapeutic Effects of (+)-Afzelechin on Particulate Matter-Induced Pulmonary Injury

Particulate matter (PM) constitutes a hazardous blend of organic and inorganic particles that poses health risks. Inhalation of fine airborne PM with a diameter of ≤ 2.5 μm (PM2.5) can lead to significant lung impairments. (+)-afzelechin (AZC), a natural compound sourced from Bergenia ligulata, boasts a range of attributes, including antioxidant, antimicrobial, anticancer, and cardiovascular effects. However, knowledge about the therapeutic potential of AZC for patients with PM2.5-induced lung injuries remains limited. Thus, in this study, we investigated the protective attributes of AZC against lung damage caused by PM2.5 exposure. AZC was administered to the mice 30 min after intratracheal instillation of PM2.5. Various parameters, such as changes in lung tissue wet/dry (W/D) weight ratio, total protein/total cell ratio, lymphocyte counts, levels of inflammatory cytokines in bronchoalveolar lavage fluid (BALF), vascular permeability, and histology, were evaluated in mice exposed to PM2.5. Data demonstrated that AZC mitigated lung damage, reduced W/D weight ratio, and curbed hyperpermeability induced by PM2.5 exposure. Furthermore, AZC effectively lowered plasma levels of inflammatory cytokines produced by PM2.5 exposure. It reduced the total protein concentration in BALF and successfully alleviated PM2.5-induced lymphocytosis. Additionally, AZC substantially diminished the expression levels of Toll-like receptors 4 (TLR4), MyD88, and autophagy-related proteins LC3 II and Beclin 1. In contrast, it elevated the protein phosphorylation of the mammalian target of rapamycin (mTOR). Consequently, the anti-inflammatory attribute of AZC positions it as a promising therapeutic agent for mitigating PM2.5-induced lung injuries by modulating the TLR4-MyD88 and mTOR-autophagy pathways.

Therapeutic Effects of Cornuside on Particulate Matter-Induced Lung Injury

Particulate matter (PM) is a mixture comprising both organic and inorganic particles, both of which are hazardous to health. The inhalation of airborne PM with a diameter of ≤2.5 μm (PM_2.5) can cause considerable lung damage. Cornuside (CN), a natural bisiridoid glucoside derived from the fruit of Cornus officinalis Sieb, exerts protective properties against tissue damage via controlling the immunological response and reducing inflammation. However, information regarding the therapeutic potential of CN in patients with PM_2.5-induced lung injury is limited. Thus, herein, we examined the protective properties of CN against PM_2.5-induced lung damage. Mice were categorized into eight groups (n = 10): a mock control group, a CN control group (0.8 mg/kg mouse body weight), four PM_2.5+CN groups (0.2, 0.4, 0.6, and 0.8 mg/kg mouse body weight), and a PM_2.5+CN group (0.2, 0.4, 0.6, and 0.8 mg/kg mouse body weight). The mice were administered with CN 30 min following intratracheal tail vein injection of PM_2.5. In mice exposed to PM_2.5, different parameters including changes in lung tissue wet/dry (W/D) lung weight ratio, total protein/total cell ratio, lymphocyte counts, inflammatory cytokine levels in the bronchoalveolar lavage fluid (BALF), vascular permeability, and histology were examined. Our findings revealed that CN reduced lung damage, the W/D weight ratio, and hyperpermeability caused by PM_2.5. Moreover, CN reduced the plasma levels of inflammatory cytokines produced because of PM_2.5 exposure, such as tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and nitric oxide, as well as the total protein concentration in the BALF, and successfully attenuated PM_2.5-associated lymphocytosis. In addition, CN substantially reduced the expression levels of Toll-like receptors 4 (TLR4), MyD88, and autophagy-related proteins LC3 II and Beclin 1, and increased protein phosphorylation of the mammalian target of rapamycin (mTOR). Thus, the anti-inflammatory property of CN renders it a potential therapeutic agent for treating PM_2.5-induced lung injury by controlling the TLR4-MyD88 and mTOR-autophagy pathways.