Inding that patients with high SIRT3 expression survived longer could be supported by that SIRT3 was capable of inducing apoptosis. In colorectal carcinoma, SIRT3 was response to stress-induced apoptosis [37]. In leukemia cells, increasing SIRT3 contributed to apoptosis caused by Kaempferol treatment [45]. In HCC cells, overexpression of SIRT3 led to activation of JNK and the resulting apoptosis [19]. Importantly, low SIRT3 expression associated to markedly shorter period of clinical recurrence. This observation suggests that more attention should be paid to HCC patients with low SIRT3 expression during and after the process of therapy, though further investigation and validation are required before a clinical practice. Interestingly, the prognostic effect of SIRT3 is especially strong in stratified survival analysis of HCC, according to the 17460038 factors attributed to worse outcome. Low SIRT3 expression therefore could identify a subgroup of HCC patients who accompany withpatients with serum AFP (,20 ng/ml), or tumor size (,5 cm), or stage (I I), or grade (I I). (DOC)Table S1 Hazard ratios of univariate analysis.(DOC)Table S2 Cox multivariate get AKT inhibitor 2 analyses of prognostic factors on recurrence-free survival. (DOC)Author ContributionsConceived and designed the experiments: CZYZ JPY. Performed the experiments: CZYZ LLL YHP JF. Analyzed the data: CZYZ MYC YC. Contributed reagents/materials/analysis tools: MYC. Wrote the paper: CZYZ LLL YHP.
Decline in cognition is closely associated with age-related structural and functional changes of neurons leading to synaptic dysfunction [1]. Synaptic activity is critically dependent on robust mitochondrial function for sufficient supply of ATP. Pathological ageing involving the accumulation of b-amyloid (Ab, a cleavage product of Amyloid Precursor Protein (APP)) in Alzheimer’s disease (AD) further illustrates the involvement of mitochondrial dysfunction in neurodegenerative disease: mutant APP and Ab enter mitochondria and interact with mitochondrial proteins, thereby disrupting the electron transport chain (ETC), increasing reactive oxygen species (ROS) to damaging levels and inhibiting the generation of ATP [2,3]. A mitochondrial protein that has been shown to be critical for the maintenance of appropriate ROS levels and ATP output is the sirtuin family member, SIRT3 [4,5]. SIRT3 has, after some controversy, now convincingly been demonstrated to reside in the mitochondrial matrix and is expressed in multiple Peptide M tissues including kidney, heart, liver, adipose tissue and brain [6]. SIRT3 is upregulated in response to fasting and calorie restriction and has been shown to reduce ROS levels in adipocytes [7] and cardiomyocytes [8] and to reduce oxidative damage and enhance the mitochondrial glutathione antioxidant defense system in cochlear neurons [9]. Substrates activated by SIRT3-mediateddeacetylation include a number of proteins critical for the maintenance of mitochondrial metabolic balance[4,5,9?5], and SIRT3-deficient mice show significantly enhanced acetylation of these, leading to increased oxidative damage in multiple tissues [9,16]. Furthermore, Kim et al. demonstrated that SIRT3 is neuroprotective against NMDA-mediated excitotoxicity in vitro [17]. Given its role in maintaining mitochondrial function, we hypothesized that SIRT3 might be involved in the mitochondrial mechanisms sensing and tackling conditions of pathological neuronal dysfunction, such as during oxidative stress in AD.Results Mouse CNS SIRT3 i.Inding that patients with high SIRT3 expression survived longer could be supported by that SIRT3 was capable of inducing apoptosis. In colorectal carcinoma, SIRT3 was response to stress-induced apoptosis [37]. In leukemia cells, increasing SIRT3 contributed to apoptosis caused by Kaempferol treatment [45]. In HCC cells, overexpression of SIRT3 led to activation of JNK and the resulting apoptosis [19]. Importantly, low SIRT3 expression associated to markedly shorter period of clinical recurrence. This observation suggests that more attention should be paid to HCC patients with low SIRT3 expression during and after the process of therapy, though further investigation and validation are required before a clinical practice. Interestingly, the prognostic effect of SIRT3 is especially strong in stratified survival analysis of HCC, according to the 17460038 factors attributed to worse outcome. Low SIRT3 expression therefore could identify a subgroup of HCC patients who accompany withpatients with serum AFP (,20 ng/ml), or tumor size (,5 cm), or stage (I I), or grade (I I). (DOC)Table S1 Hazard ratios of univariate analysis.(DOC)Table S2 Cox multivariate analyses of prognostic factors on recurrence-free survival. (DOC)Author ContributionsConceived and designed the experiments: CZYZ JPY. Performed the experiments: CZYZ LLL YHP JF. Analyzed the data: CZYZ MYC YC. Contributed reagents/materials/analysis tools: MYC. Wrote the paper: CZYZ LLL YHP.
Decline in cognition is closely associated with age-related structural and functional changes of neurons leading to synaptic dysfunction [1]. Synaptic activity is critically dependent on robust mitochondrial function for sufficient supply of ATP. Pathological ageing involving the accumulation of b-amyloid (Ab, a cleavage product of Amyloid Precursor Protein (APP)) in Alzheimer’s disease (AD) further illustrates the involvement of mitochondrial dysfunction in neurodegenerative disease: mutant APP and Ab enter mitochondria and interact with mitochondrial proteins, thereby disrupting the electron transport chain (ETC), increasing reactive oxygen species (ROS) to damaging levels and inhibiting the generation of ATP [2,3]. A mitochondrial protein that has been shown to be critical for the maintenance of appropriate ROS levels and ATP output is the sirtuin family member, SIRT3 [4,5]. SIRT3 has, after some controversy, now convincingly been demonstrated to reside in the mitochondrial matrix and is expressed in multiple tissues including kidney, heart, liver, adipose tissue and brain [6]. SIRT3 is upregulated in response to fasting and calorie restriction and has been shown to reduce ROS levels in adipocytes [7] and cardiomyocytes [8] and to reduce oxidative damage and enhance the mitochondrial glutathione antioxidant defense system in cochlear neurons [9]. Substrates activated by SIRT3-mediateddeacetylation include a number of proteins critical for the maintenance of mitochondrial metabolic balance[4,5,9?5], and SIRT3-deficient mice show significantly enhanced acetylation of these, leading to increased oxidative damage in multiple tissues [9,16]. Furthermore, Kim et al. demonstrated that SIRT3 is neuroprotective against NMDA-mediated excitotoxicity in vitro [17]. Given its role in maintaining mitochondrial function, we hypothesized that SIRT3 might be involved in the mitochondrial mechanisms sensing and tackling conditions of pathological neuronal dysfunction, such as during oxidative stress in AD.Results Mouse CNS SIRT3 i.