Sam-Sik Kang

Antiallergic effect of the root of Paeonia lactiflora and its constituents paeoniflorin and paeonol

The root of Paeonia lactiflora PALL (PL, Family Paeoniaceae) has been used frequently as an antipyretic and anti-inflammatory agent in traditional medicines of Korea, China and Japan. To evaluate antiallergic effect of PL, we isolated its main constituents, paeoniflorin and paeonol, and evaluated in vivo their inhibitory effects against passive cutaenous anaphylaxis (PCA) reaction induced by IgE-antigen complex and scratching behaviors induced by compound 48/80. PL, paeoniflorin and paeonol potently inhibited PCA reaction and scratching behaviors in mice. Paeoniflorin exhibited the most potent inhibition against scratching behaviors and the acetic acid-induced writhing syndrome in mice. Paeonol most potently inhibited PCA reaction and mast cells degranulation. These findings suggest that PL can improve IgE-induced anaphylaxis and scratching behaviors, and may be due to the effect of its constituents, paeoniflorin and paeonol.

Protective effect of esculetin against oxidative stress-induced cell damage via scavenging reactive oxygen species

AbstractAim:To investigate the anti-oxidant properties of esculetin (6,7-dihydro-xycoumarin) against H2O2-induced Chinese hamster lung fibroblast (V79-4) damage.Methods:The radical scavenging activity was assessed by 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical, hydroxyl radical, and intracellular reactive oxygen species (ROS). In addition, lipid peroxidation was assayed by the measure of related substances which react with thiobarbituric acid. The amount of carbonyl formation in protein was determined using a protein carbonyl ELISA kit. As well, cellular DNA damage was detected by Western blot and immuno-fluorescence image. Cell viability was assessed by 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium bromide assay.Results:Esculetin exhibited DPPH radical scavenging, hydroxyl radical scavenging, and intracellular ROS scavenging activities. The radical scavenging activity of esculetin resulted in the protection of cells from lipid peroxidation, protein carbonyl, and DNA damage induced by H2O2. Therefore, esculetin recovered cell viability exposed to H2O2.Conclusion:Esculetin efficiently attenuated the oxidative stress induced cell damage via its anti-oxidant properties. As a result, esculetin may be useful in the development of functional food and raw materials of medicine.