2. Definition of Aging
• Aging is easy to recognize but very difficult to
define
• However, the definition of aging indicate that
it is a progressive process associated with
decline in structure and functions, impaired
maintenance and repair system, increased
susceptibility to disease and death and
reduced reproductive capacity
3. Components of Aging
• There are two main components of aging
Aging Components
Statistical Phenotypic
5. Theories of Aging
Evolutionary Biological and Physiological
Programme death Wear and Tear
Mutation accumulation Free radical and Mitochondria theory
Antagonistic pleiotrophy UV induced free radical generation
Life History Theory Protein Glycation (AGEs)
Disposable soma theory
6.
7. Wear and tear theory of aging
Factors of aging
• Mitochondrial damage
• UV radiation
• Free radicals (Reactive oxygen species)
• Telomeres
• Apoptosis and Necrosis
• Diseases
• Other effects
17. Molecular repair mechanism
• Enzymatic and chemical mechanisms intercept
damaging ROS
• Maintenance of DNA integrity by proofreading
and repair mechanism
• Repair of some damage proteins
• Removal of aggregated protein
