For example, Chinese botanical drug formulas such as Qi Bai Ping Lung Capsule (QBPF) and Xuan Bai Cheng Qi Tang (XBCQ) improved lung function in chronic obstructive pulmonary disease (COPD) rats by increasing the relative abundance of probiotics (e.g., Akkermansia) and pathogens (e.g., Streptococcus) bacteria that are significantly associated with inflammatory biomarkers (e.g., TNF-α, IL-1β, and MMP-9) (Wang et al., 2021c; Jia et al., 2022). This evidence concerns the gene MMP9 and chronic obstructive pulmonary disease.