Anti-inflammatory effect of Eucommia Chlorogenic Acid (ECA) on adjuvant-induced arthritis rats and its effect on autophagy related pathway

Abstract

Observation ECA’s treatment effects in Adjuvant arthritis rats and relative mechanisms. The rat model of arthritis was established by subcutaneous injection of 0.2 mL Freund’s complete adjuvant. After model success, giving different ECA concentrations (25 mg/kg, 50 mg/kg and 100 mg/kg) to rats by ig methods and continued to 28 days. Measuring thymus and spleen index; observation histopathological morphology of rat joint by HE and Masson staining, and Inflammatory cells, synovial hyperplasia, oochas score and degree of fibrosis were detected semi quantitatively. The relative gene and protein expressions were measured by RT-PCR and Western blot. Compared with Normal group, Inflammatory cells, synovial hyperplasia, fibrosis and oochas score increased significantly in Model group (P<0.01, respectively); COX-1, COX-2, TNF-α, IL-1β, IL-6 and IL-17 mRNA expression were significantly up-regulation (P<0.01); AMPK, Beclin1 and ATG12 mRNA and protein expressions were significantly down-regulation (P<0.01, respectively). Compared with Model group, The inflammatory cells, the degree of fibrosis, the proliferation of synovial tissue and OOCHAS score decreased significantly in Middle and High groups (P<0.01, respectively); Thymus index significantly depressed in Low, Middle and High groups (P<0.01, respectively); spleen index were significantly down-regulation in Middle and High groups (P<0.05 or P<0.01); COX-2, TNF-α and IL-17 mRNA expression was significantly down-regulation (P<0.05), IL-1βand IL-6 mRNA expression were significantly depressed in Middle and High groups (P<0.05 or P<0.01); AMPK, Beclin1, LC3-II, ATG5 and ATG7 mRNA expressions were significantly up-regulation in Middle and High groups (P<0.05 or P<0.01); mTOR gene expression was significantly down-regulation (P<0.05), ATG12 mRNA expression was significantly up-regulation (P<0.01) in High group; AMPK, Beclin1, LC3-II, ATG5 and ATG7 protein expressions were significantly increased in High group (P<0.05 or P<0.01), mTOR protein expression were significantly down-regulation and ATG12 protein expression were significantly up-regulation in Low, Middle and High groups (P<0.05 or P<0.01, respectively). ECA can inhibit the inflammatory response in adjuvant arthritis rats, and its mechanism may be related to promoting autophagy of synovial cells.

Keywords:
ECA; autophagy; inflammatory; rheumatoid arthritis