Neovascularization,the formation of new,functional blood vessels,is highly demanded for the treatment of ischemic lesion or degenerated tissue[1].Recent attempts to employ growth factors for therapeutic angiogenesis have largely proven ineffective,due to the low stability[2]and numerous side effects (as severe as carcinogenic) of these exogenous,recombinant proteins in vivo.A safe and effective therapeutic agent that can enrich and promote the functions of endogenous pro-angiogenic growth factors will be of high demand[3].