Superoxide dismutases (SOD) is a kind of typical metalloenzymes. It has been paid much attention for its important role in life activities, such as maintaining the dynamic equilibrium of the superoxide anion radicals in vivo. At present, the simulation of SOD has been developed from small molecule compounds as active center to system simulation, in which active center was combined into polymer environment. This paper reviews the progress of SOD mimics in polymers perspective. Based on studying simulation strategies, we can get new ideas for designing and exploiting a new-type biocompatible and high reactive antioxidants. Natural polymer includes proteins and peptides, polysaccharides, molecular aggragates. Recently, steady natural proteins and gene recombined proteins or peptides have been used as SOD mimics. Polysaccharides for mimicing SOD include dextran, carboxymethyl cellulose and chitosan. Above macromolecules could conjugate with small molecule compounds with biological activity, such as metalloporphyrins, homonuclear complexes, heteronuclear complexes with new oximes ligands and salen-type metal complexes. After being conjugated, the activity of small molecule compounds had been promoted greatly, while their stability could also be improved. The environment of natural enzymes in vivo can also be simulated by inserting low molecular weight active compounds into molecular aggragates (micelles and liposomes) as the activity and circulation time of SOD mimics could be improved. Some synthetic polymers, such as polyethylene glycol (PEG), poly( L -lysine), poly(styrene-maleic anhydride), poly(cyclohexane-1,4-acetone methylene ketal) chloride, polystyrene resins, polylactic acid and block copolymers, were also used for SOD mimics. The antioxidant activity of obtained polymer grafted metal complexes was influenced by ligands. They are typical candidates of anti-cancer drugs. Contents
1 Introduction
2 Structure and simulation strategy of SOD
2.1 Structure and function of SOD
2.2 Simulation strategy of SOD
3 SOD mimics based on natural polymers
3.1 Proteins and peptides
3.2 Polysaccharides
3.3 Molecular aggregates
4 SOD mimics based on synthetic polymers
5 Summary