The Synthesis Of Fullerene-Methionine Derivate And The Protective Effect Of It On PC12 Cell Oxidative Stress Injury

Radical reaction in body must be in dynamic balance. Oxidative injury induced by excess free radicals is etiology of several diseases. It has been confirmed that more than 100 diseases are related to the excess free radicals or the inferior scavenging ability to it, so it is considered to be the modern pathopoiesis media. Compared the other tissues, never tissues are particularly sensitive to oxidative injury because of their abundant content of polyunsaturated fatty acid, the lack of antioxidase. In addition to this, neuron is hard to reproduce itself, so it is important to develop effective scavenging agent to free radicals.Fullerene, one of allotrope of carbon, has excellent potential of opposing ROS, and C60 , with a structure of icosahedral cage , is the represent of it. Fullerene derivatives have often been used as effective scavengers for reactive oxygen species (ROS). These compounds, thanks to their peculiar structure, are capable of"adding"multiple radicals per molecular, leading Krusic et al. to characterize fullerenes since 1991 as"radical sponge"and to hypothesize their potential activity as free-radical scavengers. Previous studies have pointed out that fullerene derivatives could protect against oxidative stress in organisms and prevent keratinocyte from injury induced by UV. As a matter of fact, fullerene is not able to dissolve in H2O but able to dissolve in some polar solvents such as toluene, which results in the limitation of the fullerene application in biological field. Now there are three ways of making fullerene soluble: one is to prepare soluble fullerene clathrate, the other to produce soluble fullerene collosol, another to add soluble group to the cage, and the third method is the best.In view of this background, we prepared a novel C60-Amino acid derivate (FAAD)-C60 Methionine derivative (FMD) through the organic synthesis method and described its structural characterization. Meanwhile, we investigated its scavenging capacity and regularity on superoxide and hydroxyl radical as well as its protective effects on hydrogen peroxide induced oxidative damage in rat pheochromocytoma (PC12) cells, aim to provide theoretical and experimental bases for its applications in medical field.Partâ… The Synthesis and Exosyndrome of Fullerene-Methionine DerivateObject: To synthesis soluble fullerene derivate. Methods: C60 methionine derivate was synthesized by nucleophilic addition and characterized by FT-IR,1H-NMR,RF ,UV and Size Analyzer. Results: The product was very solvable in water and stable in air, and all the equipments demonstrated that several methionines were added to fullerenes directly or indirectly. The average aquation diameter of the derivate was 11.1 nm. Conclusion: C60 methionine derivate was synthesis successfully and lyotropic in water.Partâ…¡Protective effect of fullerene-Methionine derivate on PC12 cell oxidative stress injuryObject: To investigate the scavenging ability of FMD to ROS and the antioxidant effect on PC12 oxidative stress injury induced by hydrogen peroxide. Methods: FMD of different concentration was added into pyrogallic acid-luminol and Phenanthroline oxyluminescence system to observe the scavenging effect to ROS. FMD's potential protective effect on hydrogen peroxide-induced oxidative stress and apoptotic death was investigated in PC12 cells. Cells treated with hydrogen peroxide underwent cytotoxicity and apoptotic death determined by MTT assay, flow cytometry analysis, PI/Hoechst 33342 staining. The level of MDA and the activity of SOD were measured by spectroscopy and the level of FMD into cells by fluorometric method. Results: The inhibition to ROS can be enhanced gradually as the concentration of FMD increased. After been exposed to hydrogen peroxide for 24 hours, typical morphological characteristics of injury were observed, with the proliferation activity decreased sharply and the rate of apoptosis increased obviously. Moreover, the level of MDA was increased significantly and the activity of SOD decreased in H2O2 induced group compared with control, while FMD altered the above results, restrained the reduction of PC12 caused by hydrogen peroxide, and diminished the apoptosis. In addition that, approximately 20% of total addition of FMD could enter into cells. Conclusion: FMD has good scavenging effect to ROS, and can protect PC12 cells from oxidative stress injury induced by hydrogen peroxide, which may be related to increasing the activity of anti-oxidation of PC12.