Active components from Artemisia iwayomogi displaying ONOO⁻ scavenging activity

Abstract

Peroxynitrite (ONOO(-)) is one of cytotoxic species produced by the reaction between superoxide (*O(2) (-)) and nitric oxide (NO). The main aim of this study was to identify ONOO(-) scavenging constituents from herbs. Methanolic extracts derived from one hundred thirty eight herbs were screened out for their ONOO(-) scavenging activities. Twenty herbs showed excellent ONOO(-) scavenging activity in a dose dependent manner. Of them, Artemisia iwayomogi, which showed the highest activity, was fractioned with several solvents. The ONOO(-) scavenging activity of fractions was in order of ethyl acetate (EtOAc) > n-butanol (BuOH) > dichloromethane (CH(2)Cl(2)) > water (H(2)O) fraction. The EtOAc and the n-BuOH fractions were further purified to isolate active principles by column chromatography. Apigenin 7-methylether (genkwanin), apigenin 7,4'-di-O methylether, jaceosidin, and scopoletin from the EtOAc fraction and chlorogenic acid, 2,4-dihydroxy 6-methoxy acetophenone 4-O-beta-D-glucoside, quebrachitol, and scopolin from the n-BuOH fraction were identified. The scavenging activities of chlorogenic acid (IC(50) = 0.52 +/- 0.04 microM), genkwanin (IC(50) = 1.01 +/- 0.10 microM), and scopoletin (IC(50) = 1.03 +/- 0.15 micro M) were higher than or comparable to a well-known ONOO(-) scavenger, penicillamine (IC(50) = 1.76 +/- 0.18 microM), suggesting that those compounds might be developed as effective ONOO(-) scavengers for, prevention of the ONOO(-)-involved diseases.

Laxative Effect of Agarwood Leaves and Its Mechanism

“…Meanwhile, compounds 1 and 7 had no effects on bowel movement in mice. Genkwanin, one of the flavones, has been reported to have a variety of pharmacological effects such as antioxidative, 12) radical scavenging, 13) and antimicrobial activities. 14) However, there are no reports of genkwanin having a laxative effect.…”

The “Other” Inositols and Their Phosphates: Synthesis, Biology, and Medicine (with Recent Advances inmyo‐Inositol Chemistry)

“…[174] Quebrachitol has a role to play in protecting cells due to it having antioxidant and free radical scavenging properties. [175] Acute gastric lesions can be caused by ethanol and indomethacin. Quebrachitol protects against the effects of these drugs though there is an inverse dose response: the smaller the dosage of quebrachitol the larger the protective effect, [176] although one explanation may be that the larger doses are themselves causing gastrointestinal upset.…”

A Carbohydrate Fraction, AIP1, fromArtemisia IwayomogiReduces the Action Potential Duration by Activation of Rapidly Activating Delayed Rectifier K+Channels in Rabbit Ventricular Myocytes

“…AIP1 may also act as a potent anti-oxidant. Active compounds from A. iwayomogi are potent scavengers of ONOO − , and inhibitors of inducible nitric oxide synthase [22,23]. Until now, the focus of the pharmacological effects of AIP1 has been on its anti-tumor effects, immunomodulating activity, and liver protective mechanisms.…”