ABSTRACT
Introduction 457
Zinc as an Antioxidant 458
Ionic Zinc 458
MT as an Antioxidant 458
Molecular Mechanisms of Zinc-Regulated Gene Expression 460
Expression Profiling of Zinc-Regulated Genes 464
References 468
INTRODUCTION
Zinc is defined in classical literature as a redox neutral atom. This is in contrast
to other nutrient trace elements, such as iron and copper, which change ionic
charge during biological functions. Functions of zinc have been categorized as
catalytic, structural, and regulatory (1). In each of these functional categories,
zinc plays a role more analogous to calcium, perhaps related to exchange
rates with a ligand center, in comparison with the redox metals such as
copper and iron (2). Consequently, the properties of zinc that are considered
as antioxidant in nature are indirect and do not involve direct interaction with
reactive oxidant species.