<i>Polygonum odoratum</i> Lour. Extract Attenuates Cytotoxicity and Suppresses Pro-inflammatory Gene Expression in Particulate Matter 10-induced Human Lung Cells

Particulate matter-10 (PM10) can penetrate the lungs, leading to increased lung cell injury and inflammation. The leaf extract of <i>Polygonum odoratum</i> Lour. (PO) is rich in quercetin, a compound known for its antioxidant and anti-inflammatory properties. This study aimed to evaluate the protective effect of PO in a PM10-induced human lung cell model. PM10 samples were collected in Chiang Rai, Thailand, and tested for cytotoxicity in the human lung epithelial cell line (A549). To assess the protective effect, cells were pre-treated with PO and subsequently exposed to PM10 (100 µg/mL) for 24 hours. Cell viability and lactate dehydrogenase (LDH) activity were measured, and the expression of pro-inflammatory genes, including interleukin-1β (IL-1β), interleukin-6 (IL-6), interleukin-8 (IL-8), interleukin-13 (IL-13), and interleukin-17 (IL-17), was analyzed using quantitative real-time polymerase chain reaction (RT-qPCR). The results demonstrated that PO attenuated PM10-induced lung cell injury in a dose-dependent manner and downregulated the mRNA expression of pro-inflammatory cytokines. In conclusion, PO shows potential as an alternative treatment for mitigating PM10-induced lung damage.