RESUMEN
This study was aimed to explore the mechanism of Xin-Feng capsule (XFC) on pulmonary function of Sjogren's syndrome (SS) rat model based on the TGF-β1-ERK1 signal pathway. A total of 50 SD rats were ran-domly divided into the normal control (NC) group, model control (MC) group, hydroxychloroquine sulfate (HCQ) group, radix paeoniae alba (total glucosides of paeony capsules, TGP) group, and the XFC treatment group, with 10 rats in each group. Except the NC group, the complete Freund's adjuvant (CFA) and the same rat sub-mandibular gland antigen induced method were applied to each rat after metatarsus injection on two feet and CFA after sufficient emulsification of 0.2 mL submandibular gland protein mixed antigen induced SS. The water drink-ing quantity, body weight change, pulmonary function, ERK1, TGF-β1 protein expression and serum cell factor (IL-17, IL-4) changes were detected in each group. The results showed that compared with the NC group, the body quality and serum IL-4 of MC rats were obviously decreased, and the water drinking quantity, submandibu-lar gland / lung index, submandibular gland pathological score, ERK1, TGF-β1 integral and IL-17 were increased (P < 0.01 or P < 0.05), and the pulmonary function parameter was decreased (P < 0.01 or P < 0.05). Compared with the MC group, the body quality, pulmonary function parameters FEF50 and MMF of the XFC group were in-creased, the IL-4 expression was increased, the water drinking quantity, submandibular gland / lung index, sub-mandibular gland pathological score, serum IL-17 expression, ERK1 and TGF-β1 integral were decreased (P <0.01 or P < 0.05). Compared with the HCQ group, the body quality and IL-17 were significantly decreased in the XFC group (P < 0.01), FEF25, FEF75 and MMF were increased (P < 0.01 or P < 0.05). Compared with the TGP group, the lung index and IL-17 were decreased in the XFC group (P < 0.01 or P < 0.05). It was conclud-ed that the lung function of SS rats was declined, which is closely related to the activation of TGF-β1-ERK1 sig-nal pathway. Traditional Chinese medicine of XFC is able to downregulate the TGF-β1 expression and to restrain epithelium-mesenchymal cell transformation, in order to inhibit ERK1 phosphorylation activation and proliferation, decrease immune inflammation, in order to improve SS and lung function.