AiP1, a protein from the coelomic fluid of sea star Astropecten indicus promotes wound healing and fibrinogenolysis in vitro

Abstract

Abstract Background Marine animals are suspected to hold keys to counter several life-threatening diseases. Despite its vast biodiversity, the marine ecosystem is relatively unexplored for its therapeutic potential. This study was particularly aimed at finding a potent molecule against thrombosis from the coelomic fluid of a sea star (SCF). SCF is a reservoir of immunocytes, coelomocytes, cytokines, and other substances responsible for the exceptional regenerative potential and other bioactivities. Death due to thrombosis has increased significantly in the recent years. Healing of wounds caused due to accidents or surgical procedures is also of great significance, particularly for diabetic patients. Therefore, search for good thrombolytic and wound healing agents is being pursued by many research groups globally. Methods SCF was fractionated using ion-exchange chromatography and size exclusion HPLC to yield a potent protein, AiP1. Proteolytic assays were performed using SDS-PAGE and zymography. Cell culture studies were performed as per standard protocols. Results Purified protein, AiP1, showed fibrinogenolytic, fibrinolytic, and anti-platelet activities in a dose-dependent manner. Proteolytic activities of AiP1 were inhibited post treatment with EDTA, indicating its metalloproteinase nature. It was also devoid of cytotoxic, hemolytic, and phospholipase activities. Scratch wounds created on surface of HEK293 and HaCaT cells showed faster wound closure rates post treatment with AiP1 compared to untreated cells. Peptide mass fingerprinting showed the presence of vWFA-like domain in the central β sheet which may be responsible for its bioactivities. AiP1 was thus isolated and characterized for its thrombolytic and wound healing potential. Conclusion Coelomic fluid of sea stars contains many bioactive compounds. One such compound is the protein AiP1 containing a vWFA-like domain. This protein showed significant wound healing and thrombolytic activities in vitro. Graphical abstract

Keywords

• Astropecten indicus
• Bioactive peptide
• Marine natural product
• Wound healing
• Fibrinogenolysis
• von Willebrand factor