Expression of SIRT1 and SIRT3 varies according to age in mice / 대한해부학회지

Sirtuins (SIRTs) are involved in multiple cellular processes including those related to aging, cancer, and a variety of cellular functions including cell cycle progression, DNA repair, and cellular proliferation. SIRTs have been shown to extend the yeast life span, although there is presently little known about SIRT expression in the organs of mice. In the present study, we were especially interested in identifying differences in SIRT expression between young mice and aged mice. Specifically, we investigated the expression of SIRT1 and SIRT3 in the kidney, lung, skin, adipose tissue, and spleens of 6-month-old and 24-month-old mice using immunohistochemical staining. Compared with that in younger mice, the expression of SIRT1 in 24-month-old rats was increased in kidney, lung, and spleen tissue, while that of SIRT3 was decreased in adipose, kidney, and lung tissue. The results of our study suggest that aging is associated with altered patterns of expression of SIRT1 and SIRT3. In addition, we noted that the expression patterns of SIRT1 and SIRT3 varied by organ. Taken together, the results of this study suggest the possibility that SIRTs may be involved in diseases associated with aging.

Carcinogenic Compounds, 2-nitrofluorene and Clonidine Can Modulate the Level of Sirtuin mRNAs Expression in Human Adipose Tissue-derived Stem Cells / 체질인류학회지

Sirtuins (SIRTs) are involved in multiple cellular processes. And they are involved in cellular pathways related aging, cancer, and a variety of cellular functions including cell cycle, DNA repair and proliferation. Also they modulate life span. Stem cells have the ability to self-renew for unlimited proliferation and differentiate into various cell types. It has been a little known that the mutation of undifferentiated stem cells in tissue may result in the development of cancer cells by genotoxic carcinogens. Therefore, this study investigated whether some carcinogenic compounds can modulate the expression of sirtuin mRNA on human adipose-derived stem cells. Adipose-derived stem cells (ADSC) were exposed to genotoxic carcinogenic compound (2-nitrofluorene, 2NF) and non-genotoxic carcinogenic compound (clonidine, CND) for 24 hours, 48 hours, 72 hours and 96 hours. The expression of SIRT1 mRNA increased on 72 hours. Expressions of SIRT2 and SIRT7 mRNA increased robustly on 48 hours. But all of SIRTs decreased to a level before a treatment of genotoxic compound on adipose-derived stem cells. These results demonstrated that a treatment of genotoxic compound induced the expression of SIRT mRNA only in the short time. But their level returned to untreated cells on 96 hours. They suggest that the possibility that the sirtuins can retard the carcinogenesis of adipose derived stem cells.