[Xinfeng Capsule improves lung function by regulating Notch/Jagged-HES axis of type II alveolar epithelial cells in...

Objective To observe the effect of Xinfeng Capsule (XFC) on Notch/Jagged-HES of type II alveolar epithelial cells (AECII). Methods Rats were divided for four groups: normal control (NC) group, model control (MC) group, leflunomide (LEF) group, XFC group, with 10 rats in each group. Complete Freund's adjuvant (CFA) was injected in the right foot plantar skin of each rat except for the NC group. After adjuvant arthritis was successfully induced, LEF group was given LEF (0.5 mg/100 g), and XFC group was treated with XFC (0.034 g/100 g), once a day from the 13th day to the 42th day. The NC and MC groups were given normal saline instead. Swelling degree (SD), arthritis index (AI) and pulmonary function were observed. AECII was observed by transmission electron microscopy (TEM). The expressions of transforming growth factor β1 (TGF-β1), Notch1, Notch3, Jagged1 and HES1 proteins in AECII were detected by Western blotting. Results The pulmonary function parameters such as forced expiratory volume in 1 second (FEV1), maximum expiratory flow rate at 50% FVC (FEF₅₀), instantaneous flow at 75% of expired volume (FEF₇₅), peak expiratory flow (PEF) in the MC group were significantly lower than those in the NC group, and the expressions of TGF-β1, Notch1, Notch3, Jagged1 and HES1 in AECII increased. The ultrastructure of AECII was damaged. Compared with the MC group, FEV1, FEF₅₀, FEF₇₅ and PEF increased, and TGF-β1, Notch1, Notch3, Jagged1 and HES1 decreased in the XFC group. Compared with LEF group, the lung function was better in XFC group. Conclusion XFC can inhibit pulmonary fibrosis and improve pulmonary function by down-regulating TGF-β1, Notch1, Notch3, Jagged1 and HES1 in rats with adjuvant arthritis.