Preventive effect of Ophiopogon japonicus polysaccharides on an autoallergic mouse model for Sjogren's syndrome by regulating the Th1/Th2 cytokine imbalance

Sjogren's syndrome (SS) is an autoimmune disorder characterized by lymphocytic infiltration of salivary and lacrimal glands leading to xerostomia and keratoconjunctivitis sicca. Evidence has accumulated suggesting that a Th1/Th2 cytokine imbalance has a role in the pathogenesis of SS. Currently, only palliative treatment is available. Ophiopogon japonicus, a common Chinese herbal, has been used to treat sicca-associated disorders in traditional Chinese medicine for centuries.In this study, we constructed an autoallergic mouse model for SS by immunizing C57BL/6 mouse with submandibular gland (SMG) autoantigen. At the same time, Ophiopogon japonicus polysaccharides (OJP) was administered and hydroxychloroquine was served as positive control. During the 4 weeks' experiment, salivary flow rates were determined every week, body weight, food and water intake were measured every 2 days. After death, serum were collected for IFN-gamma and IL-4 ELISA analysis and the IFN-gamma/IL-4 was calculated, SMG and spleen were harvested for organ index calculation, and part of SMG was examined for histological changes.Results showed that immunization with SMG autoantigen induced decreased salivary flow and body weight, increased water intake, SMG index, spleen index, IFN-gamma level and IFN-gamma/IL-4 ratio compared with the normal group. However, administration of the OJP could improve these data and the pathological changes of SMG with respect to the model mice, especially the high-dose of OJP group.Thus, this study provided a basis for the use of Ophiopogon japonicus in SS.