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Antioxidant activity of 3-methyl-1-phenyl-2-pyrazolin-5-one.
Y Yamamoto1, T Kuwahara1, K Watanabe2
1a Research Center for Advanced Science and Technology , University of Tokyo , Tokyo , Japan.
Redox Report : Communications in Free Radical Research
|July 14, 2016
Summary
The anti-ischemic agent 3-methyl-1-phenyl-2-pyrazolin-5-one (MCI-186) demonstrates potent antioxidant activity. It effectively inhibits lipid peroxidation in liposomal membranes, suggesting its potential as an antioxidant in biological systems.
Area of Science:
- Biochemistry
- Medicinal Chemistry
Background:
- The anti-ischemic agent 3-methyl-1-phenyl-2-pyrazolin-5-one (MCI-186) possesses antioxidant properties.
- Understanding its antioxidant mechanism is crucial for its therapeutic applications.
Purpose of the Study:
- To investigate the antioxidant activity and mechanism of MCI-186.
- To evaluate its efficacy in inhibiting lipid peroxidation in liposomal membranes.
Main Methods:
- Assessed the oxidation rate of MCI-186 at varying pH levels.
- Identified major and minor oxidation products.
- Examined the inhibition of phosphatidylcholine (PC) liposomal membrane oxidation using both water-soluble and lipid-soluble initiators.
- Evaluated the synergistic effects of MCI-186 with ascorbate and α-tocopherol.
Main Results:
- The anionic form of MCI-186, with a pKa of 7.0, exhibited higher reactivity.
- MCI-186 effectively inhibited PC liposomal membrane oxidation initiated by both water-soluble and lipid-soluble agents.
- Combination therapy with MCI-186 and other antioxidants (ascorbate, α-tocopherol) resulted in near-complete inhibition of oxidation.
Conclusions:
- MCI-186 functions as a potent antioxidant by inhibiting lipid peroxidation.
- Its efficacy in both cell-free and cellular systems suggests significant therapeutic potential.
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