Sirtuins pathways and redox homeostasis: a pilot study on young and old monozygotic twins

Sirtuins are NAD+ dependent deacetylases that play a key role in the regulation of many processes related to homeostasis, such as the regulation of metabolism, apoptosis, DNA repair and inflammatory response. Studies on humans reported a relation between the alteration of their expression and the incidence of various diseases such as metabolic, cardiovascular, cancer and neurodegenerative diseases. According with these findings the maintenance of their optimal level of activity is considered important to ensure a low risk of pathologies related with the aging process. Indeed, SIRT1 has been correlated with the redox homeostasis maintenance and with the levels of oxidative damage, such as those affecting telomeric sequences of DNA. The aim of this study is to verify the correlation between sirtuins’ expression, histone deacetylation and redox status in young and old monozygotic twins. For this study we took advantage from blood samples of young (20-40 years old) and old (70-80 years old) monozygotic twins couple, where we analysed the expression of SIRT1 and SIRT2, Lysine acetylation proteins and Histone H4 acetylation, the protein oxidation through the detection of carbonyl groups have been analysed in PBMCs, plasma level of oxidized and reduced glutathione. The putative increase of SIRT1 and SIRT2 levels that should also lead to an improvement in redox and inflammatory homeostasis, hormonal response to stress, and in the maintenance of telomeric DNA sequences could open an interesting view in this field. Particularly the twin model can help to better understand the interaction between genetic and epigenetic effects in the age-related mechanisms.