To explore the effect of XinFeng capsule (XFC) on pulmonary function of Sjogren syndrome (SS) rat and on the TGF-β1-ERK1 signal pathway.
A total of 50 SD rats were randomly divided into normal control group, model control group and hydroxychloroquine sulfate (HCQ) group, radix paeoniae alba (total glucosides of paeony capsules, TGP) group, XFC treatment group, with 10 in each group. Except for the normal control group, the other group rats were induced to establish SS models by injecting the complete Freund's adjuvant and the same rat submandibular gland antigen (0.2 mL mixture) into bilateral posterior paw metatarsus. All the animals were examined with lung function detection instrument. Meanwhile, we recorded the changes in water consumption and body mass of the rats and observed the expressions of ERK1 and TGF-β1 using immunohistochemistry and serum cell factors (IL-17, IL-4) using ELISA.
Compared with the normal control group, the model controls had reduced body mass, lower IL-4 level, increased water consumption, submandibular gland/lung index, submandibular gland pathological score, ERK1, TGF-β1 integral and IL-17 level (P<0.01 or P<0.05), and decreased pulmonary function parameter (P<0.01 or P<0.05). Compared with model control group, in XFC treatment group body mass, pulmonary function parameter FEF(50);, maximum midexpiratory flow rate (MMF), and IL-4 expression level increased, while water consumption, submandibular gland/lung index, submandibular gland pathological score, serum IL-17 expression, ERK1, TGF-β1 integral decreased (P<0.01 or P<0.05). XFC group rats were elevated in FEF(25);, FEF(75);, MMF (P<0.01 or P<0.05) and lowered in body mass and IL-17 level (P<0.01) as compared with the HCQ group, and the pulmonary function parameters and IL-17 level all went down as compared with the TGP group (P<0.01 or P<0.05).
Lung function of SS rats degrades, which may be related to TGF-β1-ERK1 signal pathway activation. XFC can down-regulate TGF-β1 level, inhibit ERK1 phosphorylation, ameliorate immune inflammation and improve lung function.