Mechanism studies of Xinfeng capsule on improving cardiovascular function though toll-like receptor 4/nuclear factor kappa B pathway in a rat model of adjuvant arthritis

Abstract

OBJECTIVETo observe the impact of Xinfeng capsule (XFC) on cardiovascular function in adjuvant arthritis (AA) model rats and investigate the mechanism though toll-like receptor 4 (TLR4)/nuclear factor kappa B (NF-κβ) signaling pathway. METHODSSeventy rats were randomly divided into seven groups: normal control (NC), model control (MC), tripterygium glycosides tablet (TPT), methotrexate (MTX), high, moderate and low dose XFC group. The administration began from day 19 after modeling for 30 day. Paw swelling, arthritic index (AI), cardiac function indexes and myocardial pathological pattern were detected. The expression of TLR4, myeloid differentiation factor (MyD) 88, interleukin-1 receptor-associated kinase (IRAK) 1, tumor necrosis factor receptor associated factor (TRAF) 6, NF-κβ, tumor necrosis factor-alpha (TNF-α) proteins in myocardial tissue were determined by western blot method. RESULTSPaw swelling and AI in MC group increased in MC group (P < 0.01), and decreased in high and moderate dose XFC groups (P < 0.01 or P > 0.05). Left ventricular systolic pressure (LVSP), left ventricular end-diastolic pressure (LVEDP), heart rate (HR) were elevated in MC group (P < 0.01), and ± dp/dtmax and CI were reduced (P < 0.01); while LVSP, LVEDP and HR declined and ±dp/dtmax, CI improved in high dose XFC group (P < 0.05 or P < 0.01). LVSP in high dose XFC group were reduced more than other treatment groups (P < 0.05 or P < 0.01). The improvements on LVEDP, dp/dt-max were superior to MTX and low dose XFC group, and the improvement on CI was better than low dose XFC group (P < 0.05 or P < 0.01). Myocardial fibers arranged irregular in MC group with intracellular edema and mitochondria damage. The modifications on myocardial structural were shown in each treatment group, but more prominent in TPT, high and moderate dose XFC group. The proteins of TLR4, MyD88, IRAK1, TRAF6, NF-κβ, TNF-α were highly expressed in MC group, and those proteins declined in high and moderate dose XFC group (P < 0.05 or P < 0.01). High dose XFC group was superior to MTX and low dose XFC group on reducing TLR4, NF-κβ, TNF-α (P < 0.05). CONCLUSIONXFC can not only inhibit the excessive activation of TLR4/NF-κB signaling pathway and the increased inflammatory mediators, but also reduce the damage of myocardial tissue and cells.