Chapter 5 - Elimination of damaged cells-dependent antiaging strategy

Abstract

Aging is basically the inevitable and progressive decline of cells, tissues, and organisms with the passage of time. A gradual process of aging in cells, tissues, and organs accompanied by the steady waning of function are normal incidents in the lifespan of an organism. Therefore there is an urgent need to find apt interventions that slow down aging and reduce or postpone the incidence of debilitating age-related diseases. There are many antiaging strategies in development which include procedures such as augmentation of autophagy, elimination of senescent cells, transfusion of plasma from young blood, intermittent fasting, enhancement of adult neurogenesis, physical exercise, antioxidant intake, and stem-cell therapy. Mitochondrial dysfunction, telomere attrition, genomic instability, epigenetic alterations, and stem-cell exhaustion are the molecular and cellular hallmarks of aging. Manipulation of specific signaling pathways and cellular reprogramming has been shown to dramatically affect the aging process. Cellular reprogramming has enabled a new era of regenerative medicine, allowing the conversion of terminally differentiated somatic cells into pleuripotent cells via somatic cell nuclear transfer or forced expression of Yamanaka factors (Oct4, Sox2, klf4, and c-myc). Targeting forced expression of Yamanaka factors is a quite effective approach because these hallmarks are in some instances regulated through epigenetic mechanisms. During cellular reprogramming, these aging hallmarks are restored to a youthful state. Thus epigenetic reprogramming via targeting Yamanaka factors may represent an effective strategy for developing antiaging therapies.