Abstract
Aging is controlled by a complex interplay of genetic and environmental factors. This has given rise to many theories, which have been advanced to explain the mechanisms underlying both cellular and organismal aging. Recently, it has been clarified that aging is integrally related to energy metabolism and reactive oxygen species (ROS) as a by-product of the energy metabolism. ROS can readily attack a wide variety of cellular entities, resulting in damage that compromises cell integrity and function and then causes aging. To lessen the consequences of this damage, cells have evolved complex defense mechanisms. Aging may be due to oxidative damage that results from an unfavorable balance between oxidative stress and antioxidant defenses. The mechanism is conserved among many animal species and is relevant to human normal aging and age-related diseases. Much attention has been focused on the subjects of calorie restriction and antioxidation related to energy metabolism because they suggest the possibility of reducing the trajectory of aging. However, while calorie restriction is reasonably well documented in controlled studies with laboratory animals, it is still necessary to prove in humans.
The average life span of 65-year-old Japanese woman reaches 88 years old, and it is thought that the average life span extends up to about 95 years old when all three major diseases of cancer, cerebrovascular disease, and cardiovascular disease as age-related disease are overcome. However, it doesn't reach 120 years old as the human maximum life span. Therefore, it is necessary to clarify the mechanism of the physiological aging that exists there. It is necessary for clarifying whether the antioxidants or calorie restriction take part in physiological aging or age-related diseases, and it is the true “Anti-aging research” to control the physiological aging (biological aging) in addition to overcome age-related disease.
