Coix lachryma-jobi extract ameliorates inflammation and oxidative stress in a complete Freund’s adjuvant-induced rheumatoid arthritis model

Abstract

Abstract Context: Adlay seed [Job’s tears, Coix lachryma-jobi L. var. ma-yuen Stapf (Poaceae)] is a Traditional Chinese Medicine, which has been investigated to treat inflammatory diseases and rheumatism. Objective: This study evaluates the ameliorative effects of adlay seed extract (ASE) in a complete Freund’s adjuvant (CFA)-induced rheumatoid arthritis (RA) rats. Materials and methods: The RA Sprague–Dawley rat model was induced and randomly divided into six groups with or without ASE treatment (50, 100 or 200\u2009mg/kg). After 28\u2009d administration, the symptoms, biochemical parameters and molecular mechanisms were investigated. Results: The values of paw oedema, PGE2 and MMP-3 decreased from 1.46\u2009±\u20090.04 to 0.66\u2009±\u20090.07\u2009cm3, from 126.2\u2009±\u200911.48 to 79.71\u2009±\u20096.8\u2009pg/mL and from 142.7\u2009±\u20098.36 to 86.51\u2009±\u20095.95\u2009ng/mL, respectively; the values of body weight increased from 177.25\u2009±\u20095.94 to 205\u2009±\u20096.52\u2009g in HASE group. In addition, treatment of ASE reduced the levels of pro-inflammatory cytokines (IL-1β, TNF-α, IL-6, MCP-1), and increased the activities of antioxidant enzyme (GSH-Px, SOD, and CAT). Furthermore, ASE could suppress the mRNA expression of COX-2 and CHI3L1 and improve the mRNA expression of CAT and GPx-1 in ankle tissues of RA rats. Discussion and conclusions: For the first time, our results indicated ASE exerts anti-RA effects via inhibiting pro-inflammatory factors and alleviating oxidative stress. Our finding sheds light on the research and development of anti-RA functional foods from adlay seed.