l-carnitine: Structure and Function

l-carnitine is found in nearly all living cells. l-carnitine present in human body can be either provided by a biosynthetic pathway or by food. Carnitine plays a major role in lipid and energy metabolism. In the human body, the primary role of l-carnitine is to shuttle long-chain fatty acids into the mitochondria where they are used to produce energy. l-carnitine is also involved in the peroxisomal oxidative metabolism and serves as a cofactor for various enzymatic reactions. Several reports suggest that l-carnitine may act as an anti-oxidant agent and limit the deleterious effects of free radicals. Many studies have estimated the role and the potential effectiveness of l-carnitine in various physiological and pathophysiological states such as physical exercise, heart disease, aging, weight management and brain function. A deficiency in l-carnitine has marked effects on the function of skeletal muscle, heart and nervous cells. Key Concepts: Carnitine is a cofactor for many enzymatic reactions. Carnitine regulates various physiological functions. Carnitine may limit ROS attack. Keywords: l-carnitine; lipid metabolism; mitochondria; peroxisome; muscle; physiology; nutrition