Differential expression of sirtuins in the aging rat brain

Braidy, Nady; Poljak, Anne; Grant, Ross; Jayasena, Tharusha; Hussein, M. A.; Chan‐Ling, Tailoi; Smythe, George A.; Sachdev, Perminder S.; Guillemin, Gilles J.

doi:10.3389/fncel.2015.00167

Cited by 126 publications

(99 citation statements)

References 91 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…28 However, a recent report indicated that increase in SIRT2 levels in aged rat brain is specific only to occipital region and no other regions. 36 In contrast to the results of our study, a recent report by Kilic Eren et al, (2015) 37 showed decrease in SIRT2 levels in resveratrol induced premature senescence in human fibroblasts. Thus, the reports are contradictory and in general the published reports till now point toward role of SIRT2 loss or overexpression as a cause for senescence induction.…”

Section: Discussioncontrasting

confidence: 99%

Increased expression of SIRT2 is a novel marker of cellular senescence and is dependent on wild type p53 status

2016

View full text Add to dashboard Cite

Sirtuins (SIRT) belonging to the NADC dependent histone deacetylase III class of enzymes have emerged as master regulators of metabolism and longevity. However, their role in prevention of organismal aging and cellular senescence still remains controversial. In the present study, we now report upregulation of SIRT2 as a specific feature associated with stress induced premature senescence but not with either quiescence or cell death. Additionally, increase in SIRT2 expression was noted in different types of senescent conditions such as replicative and oncogene induced senescence using multiple cell lines. Induction of SIRT2 expression during senescence was dependent on p53 status as depletion of p53 by shRNA prevented its accumulation. Chromatin immunoprecipitation revealed the presence of p53 binding sites on the SIRT2 promoter suggesting its regulation by p53, which was also corroborated by the SEAP reporter assay. Overexpression or knockdown of SIRT2 had no effect on stress induced premature senescence, thereby indicating that SIRT2 increase is not a cause of senescence; rather it is an effect linked to senescence-associated changes. Overall, our results suggest SIRT2 as a promising marker of cellular senescence at least in cells with wild type p53 status.

show abstract

Section: Discussioncontrasting

confidence: 99%

Increased expression of SIRT2 is a novel marker of cellular senescence and is dependent on wild type p53 status

2016

View full text Add to dashboard Cite

show abstract

“…Such divergent age-related changes may reflect different roles of SIRT7 in various fat depots. Although nervous tissue completely differs in morphology and function from WAT, it is worth noting that SIRT7 mRNA and protein levels increased with aging only in the frontal lobe but not in the temporal lobe, occipital lobe, or the hippocampus of old female rats [18]. Therefore, SIRT7 expression shows variability not only among different tissues but also in diverse locations of a tissue.…”

Section: Discussionmentioning

confidence: 99%

Age-Related Changes in Sirtuin 7 Expression in Calorie-Restricted and Refed Rats

et al. 2015

View full text Add to dashboard Cite

Background: Sirtuins (SIRT1-7) have been implicated to mediate the beneficial effects of calorie restriction for healthy aging. While the physiological functions of SIRT7 are still poorly understood, SIRT7 has recently been shown to affect ribosome biogenesis, mitochondrial gene expression, and hepatic lipid metabolism. Objective: To analyze the effects of age and short-term calorie restriction (SCR) and subsequent refeeding on SIRT7 expression in key metabolic tissues. Methods: Four- and 24-month-old male Wistar rats were subjected to 40% SCR for 30 days, followed by ad libitum feeding for 2 or 4 days. Liver, white adipose tissue (WAT), heart and skeletal muscle samples were analyzed by real-time PCR and Western blotting for SIRT7 mRNA and protein expression, respectively. Results: Aging had diverse effects on SIRT7 levels in lipogenic tissues: both the mRNA and protein levels increased in the retroperitoneal depot (rWAT), did not change in the epididymal depot (eWAT), and decreased in the subcutaneous depot (sWAT) and the liver of old as compared to young animals. In the heart, extensor digitorum longus muscle (EDL) and soleus muscle (SOL), Sirt7 gene but not protein expression was lower in old than in young control rats. SCR did not affect SIRT7 expression in WAT and the liver in both age groups. In the heart of young animals, SCR did not affect SIRT7 mRNA or protein level. In EDL, SIRT7 protein but not mRNA levels decreased after SCR and remained reduced upon refeeding. In SOL, both SIRT7 mRNA and protein expression were inhibited by refeeding. In old rats, cardiac Sirt7 expression increased after SCR and refeeding. In old rats' EDL and SOL muscles, SIRT7 protein expression was inhibited by refeeding. Conclusion: Age-related changes of SIRT7 gene expression in key organs of energy homeostasis are tissue dependent.

show abstract

“…The multiple levels of sirtuin regulation SIRT1 to -7 are expressed in the brain and undergo regulation in response to a number of stimuli leading to high regional and developmental variation [169,209] which is modified in the course of ageing [23] and numerous diseases. The transcriptional and post-transcriptional regulation of sirtuins ( Fig.…”

Section: Introductionmentioning

confidence: 99%

Sirtuins and their interactions with transcription factors and poly(ADP-ribose) polymerases

Jęśko¹,

Strosznajder²

2016

View full text Add to dashboard Cite

A b s t r a c tSirtuins vast number of targets in many cellular compartments, and some display additional enzymatic activities including mono(ADP-ribosyl)ation. SIRTs interact with multiple signalling proteins, transcription factors and enzymes including p53, FOXOs (forkhead box subgroup O), PPARs (peroxisome proliferator-activated receptors), NF-κB, and DNA-PK (DNA-dependent protein kinase). Sirtuins also interact extensively with the family of poly(ADPribose) polymerases (PARPs), a crucial and widespread class of NAD

show abstract

Differential expression of sirtuins in the aging rat brain

Cited by 126 publications

References 91 publications

Increased expression of SIRT2 is a novel marker of cellular senescence and is dependent on wild type p53 status

Increased expression of SIRT2 is a novel marker of cellular senescence and is dependent on wild type p53 status

Age-Related Changes in Sirtuin 7 Expression in Calorie-Restricted and Refed Rats

Sirtuins and their interactions with transcription factors and poly(ADP-ribose) polymerases

Contact Info

Product

Resources

About