초록
Objectives: It is well known that aging and aging-related diseases are linked to the increased level of oxidative stress caused by reactive oxygen species(ROS) and reactive nitrogen species(RNS). Nonprotein-SH decreases during aging, while substances such as ROS, nitric oxide(NO), peroxynitrite($ONOO^-$), myeloperoxidase(MPO), and dityrosine show a significant increase. This study investigated the effect of Ichungwhan on the aging process by examining its effect on the generation of the above-mentioned substances. Methods: Four comparison groups of SD rats were used. They were 6 month-old rats, 24 month-old rats, and 24 month-old rats fed with food containing 0.1% and 0.3% of Ichungwhan extract. The amount of NO, $ONOO^-$, and ROS in the rats' kidneys were examined using a fluorescence microplate reader. The reagents used for this purpose include: dihydrorhodamine 123 (DHR 123), 2',7' -dichlorodihydrofluorescein, diacetate(DCFDA), and 4,5-diaminofluorescein(DAF-2). A spectrophotometer was used to investigate the reactivity of nonprotein-SH and myeioperoxidase(MPO), using reagents such as trichloroacetic acid(TCA) and tetramethylbenzidine(TMB). The amounts of MPO protein and dityrosine were measued by western blot. Results: The observed effects of Ichungwhan on rats were as follows: increase of nonprotein-SH; effective decrease of RNS level by suppression of the generation system of $ONOO^-$ and NO; decrease of ROS level; decrease of the MPO reactivity and the subsequent reduction of amount of MPO protein; retardation of dityrosine formation. It can be hypothesized, therefore, that Ichungwhan affects both the earlier and later phases of the molecular inflammatory process, and retards the aging process. Conclusions: Empirical evidence in this study supports a role for Ichungwhan in generation mechanisms of aging process-linked substances ROS, NO, $ONOO^-$, nonprotein-SH, MPO and dityrosine. Affects contrary to the aging process observed in rats beg further empiricism to investigate potential application of Ichungwhan as a medication for age-related diseases in humans.