ABSTRACT
Ion channels are integral membrane proteins that provide a major pathway for ions across membranes. As such, ion channels are present in virtually any type of excitable and non-excitable cell. In humans, ion channels are of essential importance in countless physiological functions and can cause both congenital and acquired diseases. During aging ion channels exhibit alterations in their function, expression, or both. Many types of ion channels contain cysteine and methionine residues that become potential targets of the reactive oxygen species (ROS) that are released in the cells during aging. A large body of evidence shows that ROS modify voltage-gated calcium (Cav) and potassium (Kv) channels, ryanodine receptors (RyR), calcium-activated potassium (KCa) channels, and ATP-sensitive potassium (K[ATP]) leading to defective calcium handling and repolarization in muscle, vascular, and neuronal cells. The status of current studies indicates that oxidation of ion channels by ROS is a widespread mechanism of aging vulnerability in both vertebrates and invertebrates.
