Identifying Reliable Diagnostic/Predictive Biomarkers for Rheumatoid Arthritis

Introduction and objective: Elevated C-reactive protein is usually a good indicator of rheumatoid arthritis (RA); however, there are limitations that compromise its specificity and therefore there is an urgent need to identify more reliable diagnostic biomarkers to detect early stages of RA. In addition, identifying the correct therapeutic biomarker for the treatment of RA using methotrexate (MTX) would greatly increase the benefits experienced by the patients. Materials and methods: Primary normal synoviocytes human fibroblast-like synoviocytes (HFLS) and its phenotype rheumatic HFLS-RA cells were chosen for this study. The HFLS-RA–untreated and MTX-treated cells were subjected to microarray analysis. Results: Microarray data identified 74 differentially expressed genes. These genes were mapped against an RA inflammatory pathway, shortlisting 10 candidate genes. Gene expression profiling of the 10 genes were studied. Fold change (FC) was calculated to determine the differential expression of the samples. Discussion: The transcription profiles of the 10 candidate genes were highly induced in HFLS-RA cells compared with HFLS cells. However, on treating the HFLS-RA cells with MTX, the transcription profiles of these genes were highly downregulated. The most significant expression FC difference between HFLS and HFLS-RA (treated and untreated) was observed with HSPA6, MMP1, MMP13, and TNFSF10 genes. Conclusions: The data from this study suggest the use of HSPA6, MMP1, MMP13, and TNFSF10 gene expression profiles as potential diagnostic biomarkers. In addition, these gene profiles can help in predicting the therapeutic efficacy of MTX

Can curcuminoids be more effective than sulfasalazine for the treatment of rheumatoid arthritis?

Rheumatoid Arthritis (RA) is a debilitating, chronic autoimmune disease leading to progressive joint destruction. Current treatment includes methotrexate and sulfasalazine, however, side effects and tolerability are major limitations. Curcumin is a natural polyphenol obtained from Curcuma Longa (turmeric) that exhibits potent anti-rheumatic properties. In this study, column chromatography and preparative thin layer chromatography (PTLC) were successfully used for the isolation of 1.1747 g curcumin from turmeric. RP-HPLC method was used for monitoring the stability of curcumin and sulfasalazine following ICH guidelines. The method used was found to be linear, precise (%RSD ≤2) and accurate with good repeatability and reproducibility. Forced degradation studies demonstrated that sulfasalazine was relatively stable under stressed conditions, culminating to approximately 80-90% recovery whereas curcumin degraded completely after 60 days. At high temperatures, both compounds exhibited degradation. The therapeutic efficacy of curcumin, DMC, BDMC, methotrexate and sulfasalazine was investigated on inflammatory response genes, COL14A1, CXCL12, CYTL1, HSPA6, IFTIM1, IL-6, IL-7, MMP-1, MMP-13 and TNFSF10 that were previously identified following microarray analysis. Human Fibroblast-like Synoviocytes isolated from RA patients (HFLS-RA) were treated with the IC50 (inhibitory concentration) of the compounds and subjected to qRT-PCR analysis for measuring the expression profile of the candidate genes. CRP ELISA assay was used to confirm the findings for IL-6 gene expression in untreated and treated conditions. Curcumin exhibited increased potency in downregulating gene expression in comparison to the other treatments. Therefore, the potential use of curcumin in conjunction with the current therapies would minimise the side effects and significantly improve the outcome and quality of life for RA patients