The Polysaccharide from Dendrobium officinale Can Improve Mice with Sjögren’s Syndrome by Regulating BAFF and Fas Expressions

Exploring herbs and their compounds for potential drugs is a significant research focus due to the incurable nature of Sjögren’s syndrome (SS), a prevalent chronic inflammatory autoimmune disease. Dendrobium officinale polysaccharide (DOP) has demonstrated diverse biological effects, particularly in immunomodulation. Nonetheless, limited research has been conducted on DOP concerning the treatment of SS. This research aims to examine the impacts of DOP on experimental SS (ESS) mice and its possible mechanisms. An ESS animal model was established using the immune induction method. Besides the control group, ESS mice were randomly assigned to the model (distilled water), the HCQ (60 mg/kg), the DOP (43 mg/kg), the DOP (130 mg/kg), and the DOP (390 mg/kg) groups. Drugs were treated for three weeks. The findings indicated that DOP enhanced saliva production of ESS mice and diminished lymphocyte infiltration and foci in the submandibular gland (SMG). DOP also significantly downregulated the mRNA content of proinflammatory factors (TNF-α, IL-1β, and IL-17) and the expression of genes and proteins of apoptotic factors (Bax and Caspase-3). Furthermore, DOP downregulated the BAFF and BAFF receptor (BAFFR) as well as Fas and Fas ligand (Fas-L) expressions in the SMG. Our study demonstrates that DOP may reduce inflammation and apoptosis by inhibiting BAFF/BAFFR and Fas/Fas-L signaling, thus producing therapeutic effects in ESS mice.