Study On Oxidative Damage On Caenorhabditis Elegans By MnTE-2-PyP⁵⁺, SOD Mimic

The biological effect of ultraviolet radiation was widely concerned. There were a lot of reports on the study of damage and repairing effects of ultraviolet, but it was rarely reported which use nematode as a mode to study the mechanism about how ultraviolet radiation affects organism. We use nematode as a mode to investigate the effect of ultraviolet radiation on organism, study the impact of ultraviolet radiation on the living status of Caenorhabditis elegans, which provide the evidences for further study on biological effect and mechanism of action of ultraviolet radiation.Micromolecular MnTE-2-PyP⁵⁺ was synthetized as SOD mimetic in recent years, its study just began and rodents was used as the animal mode in most of the studies, but nematode was not introduced as animal mode to investigate the character and function of MnTE-2-PyP⁵⁺. This study investigates the protective and repairing effect of MnTE-2-PyP⁵⁺ on ultraviolet damage and juglone injury of the nematode, discusses its application and theoretical significance, which provide the evidences for the study of micromolecular mimetic and development of clinical micromolecule enzyme drug.Nematode was irradiated at 0-1500J/m² with 10 different dose of 254nm ultraviolet. Its lifespan and locomotivity were observed, the SOD activity in vivo and lipid oxidative product malonaldehyde (MDA) were determined. At low dose of UVI (0-50J/m2), lifespan was extended, locomotivity was increased, SOD activity and MDA content increased slowly and not very much. At middle dose of UVI (400-600J/m2), its lifespan decreased but relative stable, and its locomotivity decreased significantly, SOD activity and MDA content diversified complicated but relative equilibrant. At high dose of UVI (600-1500J/m2), its lifespan and locomotivity decreased significantly, SOD activity also decreased significantly, and MDA content increased significantly. The above results indicate the regulation of different UV dose on the lifespan and locomotivity of nematode can be concluded as follows: the low dose of UVI have exciting effect on nematode, at middle dose of UVI, the damage and repairing effects achieve an equilibrium and the lifespan is stable; the high dose of UVI reduced the lifespan obviously, and the damage is very hard to be repaired.Based on no toxicity of MnTE-2-PyP⁵⁺, SOD mimetic at 5ng/ml on Caenorhabditis elegans, we determine the preventive and repairing effect of MnTE-2-PyP⁵⁺ on ultra-violet damage (254nm,0-1500J/m2,8dose) and juglone injury (final concentration is 200μM). In the trial on preventive effect, the nematode was first fed with MnTE-2-PyP⁵⁺, then undertook oxidative damage; in the trial on restore effect, the worm was fed with MnTE-2-PyP⁵⁺ after oxidative damage. They both compared with the worm in the control group that fed in absence of MnTE-2-PyP⁵⁺. In the trial on preventive effect, the result of UV radiation shows that compare with control group, life span extends in the group without UV radiation; At 25-1500J/m2 there is no diversity of lift span. The result of juglone injury shows that compared with the control group, there is not any change of life span. In the trial on repairing effect, the result of UV radiation shows that compared with the control group, life span extended at a dose lower than 200J/m2; No significant diversity was found at dose of 200-1500J/ m2, life span decreased at 400J/m2; The results of juglone injury shows that compared with control group, life span was extended obviously. Under the condition of non-stress, MnTE-2-PyP⁵⁺ extends lifespan; under the stress condition (UV-C radiation and juglone injury), MnTE-2-PyP⁵⁺ does not have preventive effect on UV-C radiation and juglone injury, and it has no repairing effect on oxidative damage which is induced by high dose of UV-C radiation, but it shows repairing effect on oxidative damage induced by low dose of UV-C radiation and julglone injury. It has been proved that MnTE-2- PyPP⁵⁺ in vivo indeed plays a role of SOD, which is worth of further investigation and development.In summary, this trial sets up a mode of nematode for UV damage; It is the first time to reveal the relation between dose of UV radiation and the phaenotype of nematode and its biochemical indicators. It is also the first time to use MnTE-2-PyP⁵⁺ as SOD mimetic in the mode of nematode, which provide the evidences for utilizing ultraviolet and preventing UV damage. It is important for guiding the further study and broadening the application of micromolecular mimetic enzyme.