**4. Summary**

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 protect them from diseases typical for old age.
