Gerontology and biology consider the process of aging a continuous, universal, progressive, intrinsic and deleterious phenomenon that can progressively reduce the capability of a certain organism to maintain its homeostasis within a given environment, increasing the risk of illness or death.
In this article, we will examine the most recent theories on the biological mechanisms of aging. We will analyze the biochemical and physiological characteristics of aged organisms and senescent cells cultured in vitro. Furthermore, we will focus on the implications of data obtained from genetic experiments, in which modified longevity is achieved in animal model systems. We will then describe some examples of human genetic disorders, in which patients show signs of premature aging. In the end, we will discuss the possible implications of these most recent discoveries for the development of anti-aging drugs.