Liposome Modified with Mn−Porphyrin Complex Can Simultaneously Induce Antioxidative Enzyme-like Activity of Both Superoxide Dismutase and Peroxidase

Abstract

An antioxidative liposome catalysis that mimics both superoxide dismutase (SOD) and peroxidase (POD) activities has been developed by using the liposomes modified with lipophilic Mn-(5,10,15,20-tetrakis[1-hexadecylpyridium-4-yl]-21H,23H-porphyrin) (Mn-HPyP). The SOD- and POD-like activities of the Mn-HPyP-modified liposome were first investigated by varying the type of phospholipid, such as 1,2-distearyl-sn-glycero-3-phosphocholine (DSPC), 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC), 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC), and 1,2-dilauroyl-sn-glycero-3-phosphocholine (DLPC). Higher SOD-like activity was obtained in the case of DLPC and DMPC liposomes, in which the ligands were well-dispersed on the membrane in the liquid crystalline phase. The POD-like activity was maximal in the case of DMPC liposome, in which the Mn-HPyP complex was appropriately clustered on the membrane in the gel phase. On the basis of the above results, the co-induction of the SOD and POD activities to eliminate the superoxide and also hydrogen peroxide as a one-pot reaction was finally performed by using the Mn-HPyP-modified DMPC liposome, resulting in an increase in the efficiency of the elimination of both superoxide and hydrogen peroxide.

Use Liposome as a Designable Platform for Molecular Recognition ~ from “Statistical Separation” to “Recognitive Separation” ~

“…"raft" domains) in cells has attracted much attention because of its implications for membrane-related processes, including bacterial and viral infections and signal transductions [22]. Recent studies have also revealed that the lipid membranes can activate the biomacromolecules and regulate their functions [6][7][8][9][39][40]. Liposomes have been intensely studied as a biomimetic environment of lipid bilayers.…”

“…A liposome membrane is effective in its use as a platform to perform the above purpose because it looks after the fundamental characteristics of a conventional extraction system and the recognition surface of the biomolecule ( Figure 1). In practice, there are many reports on the possible role of a liposome membrane to recognize various molecules , such as asymmetric recognition [56-57], metal affinity [4], peptide recognition [7,58], enzyme-like function [8,59], RNA recognition [6,42,48], and others [9,28] (Figure 8). membrane modules [61], and hydrogel immobilization of the liposomes at high concentration ( Figure 9) [62].…”

“…There are some examples of the ordered structure, created on the liposome membrane through the control of its combined interactions with the target molecules [6][7][8][9]. It is rational to use the membrane surface of a liposome membrane system as a platform for the recognition of biomolecules to create a new order on its surface.…”

Characterization of Oxidized and Fragmented Superoxide Dismutase Recruited on Liposome Surface

“…1(b), the membrane fluidity was reduced in correspondence with the decrease of the SOD activity. It has been reported that the phase transition temperature of the POPC, DMPC, and DPPC liposomes are -4 ℃, 23 ℃, and 45 ℃, respectively 27) , where the POPC liposomes exists in a liquid crystalline phase at the temperature tested here. It has also reported that the membrane fluidity of the liposome could increase the hydrophobicity of the liposome surface 28, 29) .…”

Membranomics Research on Interactions between Liposome Membranes with Membrane Chip Analysis

“…On the other hand, the antioxidative activity 4 ～ 6) or gene expression system 3) have been well constructed on liposome membrane, which is called as LIPOzyme (liposome + enzyme). The previous reports on the LIPOzyme have indicated that the lipid composition and the phase state of lipid membrane, such as liquid-ordered (lo) phase, liquid-disordered (ld) phase and their mixture (ld + lo) phase, could control their function 5) . Therefore, a systematic investigation on the membrane properties as a function of the lipid composition is expected to contribute to the understanding not only on the phenomena in cell system but also on the effective design of novel biomaterials such as LIPOzyme.…”