Objective: To investigate the immunomodulatory mechanism by which Yangfei Huoxue decoction (YHD) alleviates bleomycin (BLM)-induced pulmonary fibrosis (PF) in rats.
Methods: Rats were randomly divided into two time-point groups (day 14 and 28), and each time-point group comprised the following six subgroups: control, BLM, dexamethasone (DXM), YHD high dose (YHD-H), YHD middle dose (YHD-M), and YHD low dose (YHD-L). Haematoxylin and eosin and Masson staining, flow cytometry, enzyme-linked immunosorbent assay, Western blotting and UPLC-QT of analyses were examined.
Results: The results showed that YHD reduced the degree of alveolar inflammation and fibrosis; downregulated the expression of CD28, CD80, CD86, Delta-like 1, Notch2, and Notch3; and upregulated the proportions of Th1/Th2 and Tc1/Tc2. The seven components of YHD were detected.
Conclusion: The current study indicates that YHD mainly functions by regulating the immune system and that the molecular mechanism may be related to the regulation of the Notch signaling pathway.
Keywords: Immunity; Pulmonary fibrosi; Receptors, Notch; Signal transduction; Th1-Th2 balance; Yangfei Huoxue decoction.