Study on Coelomic Fluid of Astropecten indicus and Isolation and Characterisation of a Bioactive Agent

Abstract

more than 87 percent of all the life forms available on earth. Despite its vast expanse, the newlinemarine fauna remain largely unexplored for their therapeutic potential. Of all the marine newlineanimals present, echinoderms especially sea stars (starfish) are least studied for their newlinebioactive potential. Sea stars have a remarkable regenerative potential and are model newlineorganisms for regenerative studies. Their coelomic fluid is a rich reservoir of newlineimmunocytes, coelomocytes, cytokines and secondary metabolites which have shown to newlinehave various bioactivities. newlineOur research group is predominantly focussed on investigating novel thrombolytic agents newlinefrom natural sources, both terrestrial and marine. This study was aimed at exploring these newlinetherapeutic agents from the marine source: sea star coelomic fluid. In the process of this newlineinvestigation, a biomolecule, AiP1 was isolated which also exhibited great wound healing newlineand fibrinogenolytic potential. Sea star Astropecten indicus were collected from the coast newlineof Goa, India during low tides. Sea star Coelomic Fluid (SCF) extracted from the sea newlinestars was processed and tested for its effects on fibrinogen, fibrin, platelets and on newlineviability of cultured cells in vitro. Sodium dodecyl Sulphate poly-acrylamide gel newlineelectrophoresis (SDS-PAGE) analysis showed that SCF contains various proteins and newlinepeptides. In this thesis, purification and partial characterisation of one of these proteins, newlineAiP1 is described. newlineThe coelomic fluid of sea star Astropecten indicus was fractionated using ion-exchange newlinechromatography and size exclusion high performance liquid chromatography (HPLC) to newlineyield AiP1. The purified protein showed fibrinogenolytic and fibrinolytic activity in a newlinedose dependent manner. It affected ADP and collagen induced platelet aggregation. newlineProteolytic activity of SCF and AiP1 was inhibited post-treatment with a metal chelator, newlineEthylene diamine tetra acetic acid (EDTA), indicating its metallo-proteinase nature. The newlineprotein AiP1 showed no toxicity on A549, HaCaT or HEK293 cells, in vitro. It was a