PhD, ERT, DSc, FATS, DHonC, DHonC, DHonC, HonProf, FMRAS , Academician
Aging process and its modulation: advances on biomarkers for skin regeneration and related
Telomeres which are the protective end-complexes at the termini of eukaryotic chromosomes shorten during mitotic cell division and lose their ability to divide leading to cellular senescence and aging. When telomeres become too short, cells may be unable proliferate and this situation has been linked to the development of a variety of aging-related diseases. Telomeres have an important role in the life of skin cells, including the aging of skin. Skin is a self-renewing tissue that is required to go through extensive proliferation throughout the lifespan of an organism.Telomere length have been used as a biomarker of cell senescence to explore the role of telomere shortening in photoageing induced by ultraviolet A (UVA) light and it is a useful new target for attempts to prevent it. Previous study has concluded that telomere biology is involved in the aetiology of cutaneous melanoma although the underlying mechanisms of tumorigenesis are to be fully elucidated yet. Telomerase, the tightly regulated enzyme complex that maintains telomere length in rapidly proliferating cells such as germline and cancer cells, has been implicated in having a key role in the maintenance of skin cell function and proliferation. Telomerase RNA component (TERC) and telomerase reverse transcriptase (TERT) function together to elongate telomeres and to protect chromosomal ends. Mutations in genes of the telomerase complex lead to many diseases that involve epidermal abnormalities, such as in dyskeratosis congenita. A delicate balance between telomere length and telomerase activity is required to maintain normal skin cells and avoid cancer. Previous studies have found that telomerase is not expressed in the similar race in skin cells. Human epithelial cells and fibroblasts have low levels of TERT expression although the RNA component TERC is expressed at readily detectable levels in most cell types, including skin fibroblasts and epidermal cells. On the other hand, the exogenous expression of TERC can up regulate endogenous telomerase, in primary keratinocytes and extend their lifespan. Telomerase enzyme is highly active in over 90% of all cancers since up regulation of telomerase is important for skin carcinogenesis. As an environmental barrier for the body, the skin’s exposure to ROS would suggest a role for ROS in telomere shortening and ageing in skin cells. Future studies may lead to treatments or therapies that manipulate telomerase or other factors that alter the length of telomeres, in order to slow down ageing in skin and aging-related diseases.
Professor Tsatsakis Aristidis
Professor, Academician Aristidis Tsatsakis, PhD, ERT, DSc, FATS, DHonC, DHonC, DHonC, HonProf, FMRAS.
Aristides Tsatsakis is the Director of the Department of Toxicology and Forensic Sciences of the Medical School at the University of Crete and the University Hospital of Heraklion. Dr Tsatsakis has written over 1000 publications (books and abstracts proceedings), over 400 of them in ISI journals. He is holder of several patents and has an extensive array of citations and reads /downloads to his papers. Dr Tsatsakis has given numerous keynote and plenary lectures in international congresses and was the promoter and chair of noumerous Symposiums and workshops in International Forum. He has coordinated as a PI in over 50 scientific research and technology projects and has established worldwide collaborations. Aristides Tsatsakis was elected EUROTOX President-Elect in 2012 served as President (2014-2016) of the Federation of European Toxicologists and European Societies of Toxicology. Dr. Tsatsakis has a long standing activitiy as Editor in toxicology journals. Prof. Tsatsakis is Emeritus Professor for the Federal Institute of Hygiene and Toxicology in Moscow (2014), Doctor Honoris Causa of the Mendeleev Moscow University (2016), of the Far East Federal University (FEFU), Vladivostok 2017 and of the Carol Davila, in Bucharest (2017). In 2016 was elected Foreign Member of the National Academy of Sciences of Russia (FMRAS) and in 2017 of Fellow Academy of Toxicological Sciences (FATS, USA). Aristides Tsatsakis is the inspirator, founder and chief scientific officer of the University of Crete spin-off Company ToxPlus S.A. The main research interests of Professor Tsatsakis are biomonitoring of various xenobiotics in a variety of biological samples and linking of chemical chronic exposure at low doses with health problems and diseases and risk assessments. He developed numerous biomarkers of exposure and of effects for the pesticide and chemical toxicology area uncovering the mechanistic understanding of the mode of actions and adverse outcome pathways and clinical effects.