TGFB1 and chronic obstructive pulmonary disease: In conclusion, our data indicated that imperialine mitigated pulmonary functional and structural impairment and suppressed inflammatory response in the COPD-like rat model by mediating expression of related inflammatory cytokines (IL-1β, IL-6, IL-8, TNF-α, NF-κB, and TGF-β1) and redressing the TIMP-1/MMP-9 imbalance in the lung tissues of the COPD-like rats.