Experimental Research On Sjogren’s Syndrome Treated By Therapeutic Method Of Lung-Intestine Combination Regulating The Vasoactive Intestinal Peptide

Objective:To discuss the theoretical basis of Traditional Chinese Medicine (TCM) on the mechanism of SjSgren’s syndrome (SS) treated by therapeutic method of Lung-Intestines combination. To investigate whether the adjustment of Maidongdishao Decoction(MDDSD) for the imbalance between Thl/Th2 and Thl7/Treg, and the abnormal expression of AQP5 in SS was done related to up-regulating the expression of vasoactive intestinal peptide (VIP).Method:Thirty-three female NOD mice were randomly equally divided into 3 groups as the model group, the hydroxychloroquine (HCQ) group, and the MDDSD group, and eight mice from Institute of Cancer Research (ICR) were served as the blank group.The HCQ and MDDSD groups were intragastrically administered with HCQ and MDDSD, respectively, and the blank and model groups were administered with normal saline. Mice from all 4 groups were sacrificed at the age of 18 weeks. The salivary flow rate of mice at the age of 10,13, and 16 weeks were measured. Serum cytokines interferon-y(IFN-y),interleukin-10 (IL-10), interleukin-17A (IL-17A) and vasoactive intestinal peptide (VIP) in serum and one of the submandibular glands(SMGs) were detected by enzyme-linked immunosorbent assay, while the histological changes in the other SMGs were examined by hematoxylin and eosin(HE) staining. Aquaporin 5 (AQP5) were measured by Immunohistochemical (IHC) method.Results:1.The salivary flow rate of mice in model group was significantly decreased than that in blank group, and the salivary flow rate of mice at age of 16 weeks in MDDSD group was improved(P<0.01) than that in model group.2.The VIP concentration in serum and SMGs of mice in the MDDSD group was higher(P>0.05) than that in the model group, while the level of IFN-y and IL-17A in serum and SMGs of mice in the MDDSD group was lower (P<0.01) than that in the model group. And the ratios of Thl/Th2 and Th17/Treg in the MDDSD group were lower than that in the model group (P<0.01).3.The histological score in SMGs showed more visible lymphocyte infiltration in NOD mice than that in normal mice. After treated with MDDSD, the histological score in SMGs was improved (P< 0.05). Immunohistochemistry showed that the expression of AQP5 in SMGs in the model group was significantly decreased, while the expression of AQP5 in the HCQ and MDDSD group were upregulated (P< 0.05).Conclusion:MDDSD is beneficial to the animal model of SS as NOD mice, able to improve the salivary flow rate, regulate the immunological imbalance of Th1/Th2 and Th17/Treg, reduce the lymphocyte infiltration in SMGs, and up-regulate the expression of AQP5. The mechanism of that may be related to that the expression of AQP5 in serum and SMGs was up-regulated by MDDSD.