ABSTRACT
<p><b>OBJECTIVE</b>To probe in the possible acting mechanism of Bizhongxiao Decoction (BZXD) for treatment of early active rheumatoid arthritis (RA) by way of observing the two-dimensional gel electrophoresis map of proteins in peripheral blood mononuclear cells (PBMCs) of healthy persons and RA patients (intervened or un-intervened with BZXD), analyzing the differential proteins and seeking out the RA associated proteins.</p><p><b>METHODS</b>Eighteen patients with early active RA were randomized into the BZXD group and the methotrexate (MTX) group, nine in each group, they were treated with BZXD (contained 15 Chinese herbs, as Herba Hedyotis diffusae, Herba Sarcandrae glabrae, Radix Salviae miltiorrhizae, Caulis Trachelosperi, Rhizoma Drynariae, Semen Coicis, etc.) and MTX combined with nimesulide Tablets respectively, three months as a treatment course, and their blood samples were collected for observation. Besides, blood samples from 9 healthy persons were taken as normal controls. PBMCs were isolated from blood using lymphozytes separation medium, and total protein in the cells was extracted through immobilized pH gradient two-dimensional gel electrophoresis. After Coomassie brilliant blue G250 staining, gel-image analysis was performed using PDQuest software. The differentially expressed proteins were identified by matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF-MS). Then partial proteins were validated by reverse transcription polymerase chain reaction (RT-PCR).</p><p><b>RESULTS</b>The 2-DE protein profile of PBMCs from healthy persons and RA patients before and 3 months after treatment were obtained, and 23 differential protein spots were found, 14 from 18 differential protein spots were successfully identified, of which 8 proteins were up-regulated and 6 proteins were down-regulated in RA patients as compared with control. After 3-month treatment, 5 differentially expressed proteins showed more obvious in the BZXD group than in the MTX group. RT-PCR verified that the expression of ApoA-I in all the three groups was consistent with the outcomes of 2-DE.</p><p><b>CONCLUSIONS</b>Some differentially expressed proteins exist in the PBMCs of RA patients, which may play a potential role in the pathogenesis of RA; BZXD may treat RA by way of regulating the expression of some differential proteins in patients.</p>