The ageing process manifests itself within numerous organs. Central nervous (particularly brain), immune, endocrine and cardiovascular systems functioning are impaired with age. Alternations in conjunctive and muscular tissues are other familiar ailments common to ageing humans. Material and methods: Presentation macromolecular processes The endocrine system is particularly sensitive to age. Alterations may be due to the: • diminution of the synthesis or turnover of most of hormones; • impaired functioning of hormone receptors; • defective binding between hormone and its receptor; • premature programmed death (apoptosis) of hormone producing cells; • auto-immune reactions; • cancerous transformations. Endocrine system alterations are linked to the apparition of several ageing related diseases such as diabetes, disorders in thyroid gland functioning and sexual hormones deficiencies. In ageing men, a progressive diminution of circulating levels of androgens is observed (aging male). With age, genetic material is altered at different levels. The stability of DNA is decreased, the DNA transcription and the translation of proteins are impaired. The alternation in the transmission of the genetic information results in accumulation or abnormal, no functional proteins („error theory“), leading to cellular impairment, ageing and death. At each cell division the shortening in telomeres (protecting structures at the ends of chromosomes) is observed. The progressive shortening of telomeres may be a cause (or the cause) of cellular ageing. Telomeres shortening may appear to be the cellular clock that determines the number of times cells could divide and which weakens chromosomes to the point where cell division is no longer possible. DNA methylation plays a central role in genomic imprinting and embryonic development. Aberrations in DNA methylation have been implicated in ageing and various diseases including cancer. Conclusion: The ageing is conclusive process. At least this time.

Department of Urology University Hospital in Brno Medical School Masaryk University Brno

2. český a mezinárodní andrologický kongres, Štiřín, 3.-5.5.2007