Justicia secunda leaf aqueous fraction suppressed NF-κB, TNF-α, IL-6 and COX-2 in arthritic rat

Abstract

Justicia secunda Vahl leaf is employed in folklore medicine preparation as a remedy used in the management of inflammatory disorders. Rheumatoid arthritis constitutes one of many chronic inflammatory disorders which is typified by the gradual build-up and prolonged existence of inflammatory cells in synovial joints. Pro-inflammatory mediators (Tumor necrosis factor- alpha (TNF-α), nuclear factor–kappa B (NF-κB), interleukin-6 (IL-6) and cyclooxygenase-2 (COX-2) play varied roles in the development and continuation of rheumatoid arthritis which proceeds to cause extreme damage to the host tissue. The suppression of these mediators can substantially limit their rate of migration to the cells. This study evaluated the effect of aqueous fraction of J. secunda leaves on selected inflammatory markers (NF-κB, TNF-α, IL-6 and COX-2) and its possible mechanism of action. J. secunda aqueous leaf fraction (JSALF) was tested on carrageenan, arachidonic and Complete Freund’s Adjuvant (CFA) induced rat paw inflammation models, respectively. TNF-α, NF-κB, IL-6 and COX-2 levels were analysed using enzyme-linked immunosorbent assays (ELISA). Gas Chromatography-Mass Spectrometry (GC-MS) analysis was carried out. JSALF treated animals had significantly (p < 0.05) suppressed carrageenan, arachidonic and CFA-induced paw edema when compared with untreated control animals. Serum levels of TNF-α, NF-κB, IL-6 and COX-2 were significantly reduced (p < 0.05) in JSALF-treated animals. GC-MS detected 10 suspected anti-inflammatory compounds. Findings from this study indicate that J. secunda aqueous leaf fraction substantially suppressed pro-inflammatory mediators and COX-2 pathways in arthritic rats which justifies its folkloric use in the management of inflammatory diseases