Anti-inflammatory activity of cyclo-oxygenase2 inhibitory anionic protein fraction from <i>Lamellidens marginalis</i> (Lamarck)

Abstract

Aqueous extract of freshwater mussel, <i>Lamellidens marginalis</i> is known to possess potent antioxidant and anti-inflammatory activity. Here, we have made an attempt to purify anti-inflammatory protein from <i>Lamellidens marginalis</i> extract (LME). Aqueous LME was prepared, and total protein was precipitated by 60% ammonium sulfate followed by purification through ion exchange chromatography. Isolated fractions were studied for anti-inflammatory activity in <i>in vitro</i> and <i>in vivo</i> experimental models. Active fractions were characterized by SDS PAGE and HPLC. Protein recovered from ammonium sulfate precipitation showed four distinct peaks in diethyl-aminoethyl cellulose ion exchange chromatography when eluted with stepwise salt gradient. Protein fraction eluted in 0.5 M sodium chloride solution showed maximum specific activity and anti-inflammatory activity in acute model and adjuvant induced chronic inflammation model. This fraction also showed cyclo-oxygenase 2 (COX2) enzyme inhibitory activity in <i>in-vitro</i> system. In SDS-PAGE 0.5 M NaCl fraction showed multiple bands after Coomassie brilliant blue staining and three distinct peaks in HPLC. In this study, we identified an anti-inflammatory protein fraction with high anionic property which could be attributed to inhibition of COX2 enzyme activity.