**Author details**

polygenic trait influenced by many genetic changes. In addition, longevity phenomena are influ-

The aging process may be traced based on experimental models using candidate genes enabling early detection of aging before the emergence of typical phenotypes. Such experimental model may be plants because they allow for the examination of complex mechanisms

In the last years, publications point to the involvement of many molecular factors in the development of normal aging. However, we still did not prevent the pathological changes in the

In the aging process, functions of the p53 protein, *genome trader*, are impaired. The p53 protein does not lead to repair cells with damaged DNA or does not direct them to the path of apoptosis. The effect of these functional changes is increased susceptibility to infections, autoimmune diseases and cancers, including malignancies [1, 2]. The pathogenesis of tumors

In addition, older people often develop neurological diseases including Alzheimer's and Parkinson's diseases, epilepsy, and stroke. Based on the modern knowledge, it is difficult to separate normal and pathological aging, and neurodegeneration of central neurons. More

The aging process is not limited to the central nervous system. It also includes other organs such as heart and liver. It is believed that the loss of liver regenerative capacity is disturbed in the elderly. Defective liver cells undergo apoptosis or aging. Aging cells are responsible for fibrosis and hepatocellular carcinoma. Is senescence important in hepatic diseases, available

Moreover, recently a growing interest focuses on senescent cells in the context of old age dis-

Despite current intensive research on the aging process, many questions about the pathomechanism of disorders in the old body remain unanswered. Moreover, the causes of unfavorable changes in the aging organism are not fully understood. It is not known which factors precisely define aging and/or longevity and contributes to the development of senility. Finding unknown paths in the pathogenesis of aging may improve the comfort of life of elderly and

eases, malignancy and insulin resistance, and as a therapeutic goal to prolong health.

information in the chapter, normal aging and neurodegenerative disorders.

aging organism in the form of cardiologic, neurological, or oncological diseases.

enced by both epigenetic and environmental factors.

associated with the p53 protein is contained in this book.

protect them from diseases typical for old age.

of molecular changes during aging.

2 Senescence - Physiology or Pathology

**3. Aging and old age diseases**

in this book.

**4. Summary**

Jolanta Dorszewska<sup>1</sup> \* and Wojciech Kozubski<sup>2</sup>

\*Address all correspondence to: dorszewskaj@yahoo.com

1 Laboratory of Neurobiology, Department of Neurology, Poznan University of Medical Sciences, Poznan, Poland

2 Chair and Department of Neurology, Poznan University of Medical Sciences, Poznan, Poland
