Peroxynitrite Scavenging Mechanism of <i>Zingiberis Rhizoma</i>

Shin, Sang-Guk; Jeong, Ji-Cheon

The Journal of Internal Korean Medicine > Volume 24(1); 2003 > Article

Original Article

The Journal of Internal Korean Medicine 2003;24(1): 75-83.

生薑의 Peroxynitrite 제거 기전

Peroxynitrite Scavenging Mechanism of Zingiberis Rhizoma

Sang-Guk Shin, Ji-Cheon Jeong

Department of Internal Medicine, College of Oriental Medicine, Dongguk University

Correspondence

Ji-Cheon Jeong ,Tel: 02-3416-9731, Fax: 02-3444-9171, Email: jjcjh@hitel.net

Received: December 6, 2002, Accepted: February 11, 2003, Published online: March 30, 2003.

ABSTRACT

Objectives:
Peroxynitrite (ONOO^-), formed from the reaction of O2^- and NO, is a cytotoxic species that can oxidize several cellular components such as proteins, lipids and DNA. It has been involved in the aging process and age-related diseases such as Alzheimer s disease, rheumatoid arthritis, cancer and atherosclerosis. The aim of this study was to investigate scavenging activities of ONOO^- and its precursors, NO and O2^- and its scavenging mechanism of Zingiberis Rhizoma (ZR).

Methods :
To investigate scavenging activities of ONOO^-, NO, O2^- and its scavenging mechanism, we used fluorescent probes like DCFDA, DAF-2 and DHR 123. The ONOO^- scavenging activity on ZR was assayed by measuring oxidized dihydrorhodamine 123 (DHR 123) by fluorometry. The scavenging efficacy was expressed as IC50, showing the concentration of each sample that is required to cause 50% inhibition of DHR 123 oxidation. In a separate study, the protective effect of ZR on ONOO^--induced nitration of bovine serum albumin was investigated through immuno-assay with a monoclonal anti-nitryrosine antibody, and a horseradish peroxidase-conjugated anti-mouse secondary antibody from sheep.

Results:
ZR markedly scavenged authentic ONOO^-, O2^- and NO. It also inhibited ONOO^- induced by O2^- and NO which are derived from SIN-1. The data demonstrated that ZR led to decreased ONOO^- mediated nitration of tyrosine through electron donation. It also inhibited the nitration of bovine serum albumin induced by ONOO^- in a dose-dependent manner. Furtheremore, it blocked LPS-induced ROS and RNS generation.

Conclusions:
These results suggest that ZR can be developed as an effective ONOO^- scavenger for the prevention of aging process and age-related diseases.

Key words: Peroxynitrite, Scavenging Mechanism, Zingiberis Rhizoma, nitric oxide, superoxide anion