Paeoniflorin down-regulates ATP-induced inflammatory cytokine production and P2X7R expression on peripheral blood mononuclear cells from patients with primary Sjögren's syndrome

This study determined the effects of paeoniflorin (PF) on the expression of purinergic receptor P2X ligand-gated ion channel 7 (P2X7R) expressed on peripheral blood mononuclear cells (PBMCs) and production of ATP-induced pro-inflammatory cytokines released by PBMCs in patients with primary Sjögren's syndrome (pSS). The pharmacological functions and cytotoxic effects of PF were dose dependent in PBMCs from 20 newly diagnosed pSS patients and 20 normal individuals. The optimum dose of PF was 100μM. PF significantly down-regulated the production of interleukin (IL)-1β and IL-6 from pSS PBMCs, and significantly inhibited ATP-induced expression of P2X7R, that might contribute to reduced IL-1β and IL-6. mRNA and protein levels of P2X7R on pSS PBMCs were significantly higher than in normal individuals (p=0.03, p