MAPK1 and chronic obstructive pulmonary disease: As in Figures 8(c) and 8(d), the expression of PI3K, P-AKT, and P-p38 of lung tissues were significantly increased in the model group, and I&N decreased the expression of PI3K and phosphorylation of P-AKT and P-p38 of lung tissues in COPD rats (P < 0.05).