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1.
Life Sci ; 239: 117036, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31697951

RESUMO

AIMS: Previous literature has shown that melatonin plays a critical role in protecting against cerebral ischemia/reperfusion (I/R) injury. Sirtuin3(SIRT3), as one member of the sirtuin family, protects against oxidative stress-related diseases. However, the association between melatonin and SIRT3 in cerebral I/R injury is not well understood. Our experiment was planned to investigate whether melatonin protects against cerebral I/R injury through SIRT3 activation. MAIN METHODS: We selected transient middle cerebral artery occlusion (tMCAO) mice as the model of cerebral I/R injury. Male C57/BL6 mice were pre-treated with or without a selective SIRT3 inhibitor and then subjected to tMCAO surgery. Melatonin (20 mg/kg) was given to mice by intraperitoneal injection after ischemia and before reperfusion. Then, we observed the changes in the SIRT3 and downstream relative proteins, infarction volume, neurological score, Nissl, H&E and TUNEL staining, and the expression of apoptosis proteins after tMCAO. KEY FINDINGS: Melatonin upregulated the expression of SIRT3 after tMCAO, and alleviated the neurological dysfunction and cell apoptosis through SIRT3 activation. SIGNIFICANCE: Our research proved that melatonin promoted SIRT3 expression after tMCAO and alleviated cerebral I/R injury by activating the SIRT3 signaling pathway. This study provides novel therapeutic targets and mechanisms for the treatment of ischemic stroke in the clinic, especially during cerebrovascular reperfusion.


Assuntos
Melatonina/farmacologia , Traumatismo por Reperfusão/metabolismo , Sirtuína 3/metabolismo , Animais , Apoptose/efeitos dos fármacos , Isquemia Encefálica/tratamento farmacológico , Infarto da Artéria Cerebral Média/tratamento farmacológico , Masculino , Melatonina/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Estresse Oxidativo/efeitos dos fármacos , Substâncias Protetoras/uso terapêutico , Traumatismo por Reperfusão/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Sirtuína 3/fisiologia , Acidente Vascular Cerebral/tratamento farmacológico
2.
BMC Neurol ; 19(1): 289, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31729962

RESUMO

BACKGROUND: Ischemia-reperfusion (I/R)-induced vascular dysfunction is the main factor to acute ischemic stroke. Sirt3 is one of the sirtuin family members, which plays an important role in the development of neurological diseases. METHODS: In this study, we constructed I/R injury model on HBMEC cells and induced the overexpression of Sirt3 in model cells. Meanwhile, the p38 activator U-46619 was used to examine the connection between Sirt3 and p38. We also examined the level of endothelial associated proteins, including occluding, ZO-1 and claudin-4 by using qRT-PCR and western blot. RESULTS: Our findings indicated that overexpression of Sirt3 decreased the permeability of model cells and promoted in the growth of endothelial cells. However, the activation of p38 could antagonize the function of Sirt3 in HBMEC cells. Moreover, Our results indicated a positive correlation between Sirt3 and inter-endothelial junction proteins. Importantly, PPAR-γ agonist and inhibitor were utilized to investigate the role of PPAR-γ in Sirt3 mediated cell function. Sirt3 was targeted by PPAR-γ in model cells. CONCLUSIONS: Taken together, this research not only demonstrated PPAR-γ might benefit to the growth of endothelial cell though activating Sirt3 but also indicated its potential value in the treatment for ischemic stroke.


Assuntos
Permeabilidade Capilar/fisiologia , Células Endoteliais/metabolismo , PPAR gama/metabolismo , Sirtuína 3/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/patologia , Linhagem Celular , Humanos , Acidente Vascular Cerebral/metabolismo , Acidente Vascular Cerebral/patologia
3.
Life Sci ; 237: 116954, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31610192

RESUMO

Sirt3 enzyme and mitochondrial abnormality can be related to excess fatigue or muscular dysfunction in multiple sclerosis (MS).Ellagic acid (EA) has a mitochondrial protector, iron chelator, antioxidant, and axon regenerator in neurons.In this study the effect of EAon muscle dysfunction, its mitochondria, and Sirt3 enzyme incuprizone-induced model of MSwas examined. Demyelination was induced by a diet containing 0.2% w/w cuprizone (Cup) for 42 days and EA administered daily (5, 50, and 100 mg/kg P.O) either with or without cuprizone in mice. Behavioral tests were assessed, and muscle tissue markers ofoxidative stress, mitochondrial parameters, mitochondrial respiratory chain activity, the Sirt3 protein level, and Sirt3 expression were also determined. Luxol fast blue staining and the behavioral tests were performed toassess the implemented model. In Cup group an increased oxidative stress in their muscle tissues was observed. Also, muscle mitochondria exhibited mitochondria dysfunction, lowered mitochondrial respiratory chain activity, Sirt3 protein level, and Sirt3 expression.EA prevented most of these anomalous alterations. Sub-chronicEA co-treatment dose-dependently ameliorated behavioral and muscular impairment in mice that received Cup.EA can effectively protect muscle tissue against cuprizone-induced demeylination via the mitochondrial protection, oxidative stress prevention and Sirt3 overexpression.


Assuntos
Comportamento Animal/efeitos dos fármacos , Cuprizona/toxicidade , Doenças Desmielinizantes/tratamento farmacológico , Ácido Elágico/farmacologia , Mitocôndrias Musculares/efeitos dos fármacos , Doenças Musculares/prevenção & controle , Sirtuína 3/metabolismo , Animais , Quelantes/toxicidade , Doenças Desmielinizantes/induzido quimicamente , Doenças Desmielinizantes/metabolismo , Doenças Desmielinizantes/patologia , Modelos Animais de Doenças , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias Musculares/metabolismo , Mitocôndrias Musculares/patologia , Estresse Oxidativo/efeitos dos fármacos
4.
Int J Mol Sci ; 20(19)2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31557786

RESUMO

Sirtuins (SIRTs) are seven nicotinamide adenine dinucleotide (NAD+)-dependent protein deacetylases enzymes (SIRT1-7) that play an important role in maintaining cellular homeostasis. Among those, the most studied are SIRT1 and SIRT3, a nuclear SIRT and a mitochondrial SIRT, respectively, which significantly impact with an increase in mammals' lifespan by modulating metabolic cellular processes. Particularly, when activated, both SIRT1 and 3 enhance pancreatic ß-cells' insulin release and reduce inflammation and oxidative stress pancreatic damage, maintaining then glucose homeostasis. Therefore, SIRT1 and 3 activators have been proposed to prevent and counteract metabolic age-related diseases, such as type 2 diabetes mellitus (T2DM). Physical activity (PA) has a well-established beneficial effect on phenotypes of aging like ß-cell dysfunction and diabetes mellitus. Recent experimental and clinical evidence reports that PA increases the expression levels of both SIRT1 and 3, suggesting that PA may exert its healthy contribute even by activating SIRTs. Therefore, in the present article, we discuss the role of SIRT1, SIRT3, and PA on ß-cell function and on diabetes. We also discuss the possible interaction between PA and activation of SIRTs as a possible therapeutic strategy to maintain glucose hemostasis and to prevent T2DM and its complications, especially in the elderly population.


Assuntos
Glucose/metabolismo , Homeostase , Sirtuína 1/química , Sirtuína 3/química , Animais , Diabetes Mellitus Tipo 2/etiologia , Diabetes Mellitus Tipo 2/metabolismo , Suscetibilidade a Doenças , Exercício Físico , Humanos , Células Secretoras de Insulina/metabolismo , Doenças Metabólicas/etiologia , Doenças Metabólicas/metabolismo , Sirtuína 1/metabolismo , Sirtuína 3/metabolismo
5.
Cell Physiol Biochem ; 53(3): 465-479, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31464387

RESUMO

BACKGROUND/AIMS: Cyclophilin D (CypD) mediates the mitochondrial permeability transition pore (mPTP) opening that contributes to mitochondrial dysfunction. CypD is regulated by its acetylation/deacetylation state that depends on Sirtuin-3 (SIRT3) mitochondrial deacetylase. Since obesity and metabolic syndrome decrease SIRT3 activity and expression, we tested the hypothesis that CypD hyperacetylation promotes mitochondrial dysfunction under this pathophysiological state, which is associated with ventricular dysfunction and heart failure. METHODS: Myocardial tissue samples from patients with left ventricular heart failure, with either obesity or normal weight, were processed for the expression of SIRT3 and acetylation profile by Western Blot (WB). In addition, a rat model of obesity and metabolic syndrome induced by 30% (w/v) of sucrose was conducted. The WB analysis was used to determine the levels of mitochondrial expression of SIRT3, Adenine Nucleotide Translocator (ANT), CypD and the acetylation profile, as well as immunoprecipitation to establish the acetylation levels of CypD. Mitochondrial function was assessed by oxygen consumption analysis and maximum Ca2+ retention capacity. Oxidative stress was assessed by aconitase activity, protein carbonyl and thiol groups content. RESULTS: SIRT3 expression in the biopsies of the failing human hearts showed a 46% decrease in the expression levels of obese patients in comparison to the non-obese patients (p=0.0219). Remarkably, body mass index was associated with protein acetylation (0.627; p = 0.035), suggesting that the acetylation profiles of the failing hearts of obese patients are partly mediated by a reduction in SIRT3, which is also associated with higher BNP levels, indicating a more severe ventricular dysfunction (-0.636; p = 0.043). Accordingly, obese rats demonstrated a SIRT3 mitochondrial expression decrease of 22% concomitantly with a hyperacetylated mitochondrial profile, including CypD. Cardiac mitochondria from obese animals were 2.5-fold more prone to mPTP opening than the controls. CONCLUSION: Our results indicate that obesity reduces SIRT3 expression and that CypD hyperacetylation increases mPTP opening, suggesting that the activation of SIRT3 might be a potential target to decrease ventricular dysfunction and slow the progression of heart failure.


Assuntos
Mitocôndrias Cardíacas/metabolismo , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Obesidade/metabolismo , Sirtuína 3/metabolismo , Acetilação , Adulto , Idoso , Animais , Índice de Massa Corporal , Cálcio/metabolismo , Ciclofilinas/metabolismo , Feminino , Insuficiência Cardíaca/metabolismo , Humanos , Imunoprecipitação , Técnicas In Vitro , Masculino , Síndrome Metabólica/metabolismo , Camundongos , Camundongos Knockout , Pessoa de Meia-Idade , Translocases Mitocondriais de ADP e ATP/metabolismo , Consumo de Oxigênio/fisiologia , Ratos , Ratos Wistar
6.
Mol Cell ; 75(4): 823-834.e5, 2019 08 22.
Artigo em Inglês | MEDLINE | ID: mdl-31302001

RESUMO

Sirt3, as a major mitochondrial nicotinamide adenine dinucleotide (NAD)-dependent deacetylase, is required for mitochondrial metabolic adaption to various stresses. However, how to regulate Sirt3 activity responding to metabolic stress remains largely unknown. Here, we report Sirt3 as a SUMOylated protein in mitochondria. SUMOylation suppresses Sirt3 catalytic activity. SUMOylation-deficient Sirt3 shows elevated deacetylation on mitochondrial proteins and increased fatty acid oxidation. During fasting, SUMO-specific protease SENP1 is accumulated in mitochondria and quickly de-SUMOylates and activates Sirt3. SENP1 deficiency results in hyper-SUMOylation of Sirt3 and hyper-acetylation of mitochondrial proteins, which reduces mitochondrial metabolic adaption responding to fasting. Furthermore, we find that fasting induces SENP1 translocation into mitochondria to activate Sirt3. The studies on mice show that Sirt3 SUMOylation mutation reduces fat mass and antagonizes high-fat diet (HFD)-induced obesity via increasing oxidative phosphorylation and energy expenditure. Our results reveal that SENP1-Sirt3 signaling modulates Sirt3 activation and mitochondrial metabolism during metabolic stress.


Assuntos
Cisteína Endopeptidases/metabolismo , Mitocôndrias/metabolismo , Mutação , Obesidade/metabolismo , Transdução de Sinais , Sirtuína 3/metabolismo , Sumoilação , Acetilação , Animais , Cisteína Endopeptidases/genética , Gorduras na Dieta/efeitos adversos , Gorduras na Dieta/farmacologia , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Mutantes , Mitocôndrias/genética , Mitocôndrias/patologia , Obesidade/induzido quimicamente , Obesidade/genética , Obesidade/patologia , Sirtuína 3/genética
7.
Diabetes Res Clin Pract ; 155: 107801, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31356832

RESUMO

AIM: A growing body of evidence supports the impact of intermittent fasting on normalizing body metabolism and lowering oxidative stress and inflammation. Mounting evidence confirms that oxidative stress and chronic inflammation trigger the way for the development of metabolic diseases, such as diabetes. This research was conducted to evaluate the impact of Ramadan intermittent fasting (RIF) on the expression of cellular metabolism (SIRT1 and SIRT3) and antioxidant genes (TFAM, SOD2, and Nrf2). METHODS: Fifty-six (34 males and 22 females) overweight and obese subjects and six healthy body weight controls were recruited and monitored before and after Ramadan. RESULTS: Results showed that the relative gene expressions in obese subjects in comparison to counterpart expressions of controls for the antioxidant genes (TFAM, SOD2, and Nrf2) were significantly increased at the end of Ramadan, with percent increments of 90.5%, 54.1% and 411.5% for the three genes, respectively. However, the metabolism-controlling gene (SIRT3) showed a highly significant (P < 0.001) downregulation accompanied with a trend for reduction in SIRT1 gene at the end of Ramadan month, with percent decrements of 61.8% and 10.4%, respectively. Binary regression analysis revealed significant positive correlation (P < 0.05) between high energy intake (>2000 Kcal/day vs. <2000 Kcal/day) and expressions of SOD2 and TFAM (r = 0.84 and r = 0.9, respectively). CONCLUSION: Results suggest that RIF ameliorates the genetic expression of antioxidant and anti-inflammatory, and metabolic regulatory genes. Thus, RIF presumably may entail a protective impact against oxidative stress and its adverse metabolic-related derangements in non-diabetic obese patients.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Jejum/fisiologia , Proteínas Mitocondriais/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Obesidade/fisiopatologia , Sobrepeso/fisiopatologia , Sirtuína 1/metabolismo , Sirtuína 3/metabolismo , Superóxido Dismutase/metabolismo , Fatores de Transcrição/metabolismo , Adulto , Estudos de Casos e Controles , Proteínas de Ligação a DNA/genética , Feminino , Regulação da Expressão Gênica , Humanos , Islamismo , Masculino , Proteínas Mitocondriais/genética , Fator 2 Relacionado a NF-E2/genética , Estresse Oxidativo , Estudos Prospectivos , Sirtuína 1/genética , Sirtuína 3/genética , Superóxido Dismutase/genética , Fatores de Transcrição/genética
8.
Am J Physiol Endocrinol Metab ; 317(2): E284-E297, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31184932

RESUMO

Hydrogen sulfide (H2S), a gaseous molecule, is involved in modulating multiple physiological functions, such as antioxidant, antihypertension, and the production of polysulfide cysteine. H2S may inhibit reactive oxygen species generation and ATP production through modulating respiratory chain enzyme activities; however, the mechanism of this effect remains unclear. In this study, db/db mice, neonatal rat cardiomyocytes, and H9c2 cells treated with high glucose, oleate, and palmitate were used as animal and cellular models of type 2 diabetes. The mitochondrial respiratory rate, respiratory chain complex activities, and ATP production were decreased in db/db mice compared with those in db/db mice treated with exogenous H2S. Liquid chromatography with tandem mass spectrometry analysis showed that the acetylation level of proteins involved in the mitochondrial respiratory chain were increased in the db/db mice hearts compared with those with sodium hydrosulfide (NaHS) treatment. Exogenous H2S restored the ratio of NAD+/NADH, enhanced the expression and activity of sirtuin 3 (SIRT3) and decreased mitochondrial acetylation level in cardiomyocytes under hyperglycemia and hyperlipidemia. As a result of SIRT3 activation, acetylation of the respiratory complexe enzymes NADH dehydrogenase 1 (ND1), ubiquinol cytochrome c reductase core protein 1, and ATP synthase mitochondrial F1 complex assembly factor 1 was reduced, which enhanced the activities of the mitochondrial respiratory chain activity and ATP production. We conclude that exogenous H2S plays a critical role in improving cardiac mitochondrial function in diabetes by upregulating SIRT3.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Complexo II de Transporte de Elétrons/efeitos dos fármacos , Complexo I de Transporte de Elétrons/efeitos dos fármacos , Sulfeto de Hidrogênio/farmacologia , ATPases Mitocondriais Próton-Translocadoras/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Sirtuína 3/metabolismo , Acetilação/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Respiração Celular/efeitos dos fármacos , Células Cultivadas , Diabetes Mellitus Experimental/patologia , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patologia , Complexo I de Transporte de Elétrons/metabolismo , Complexo II de Transporte de Elétrons/metabolismo , Metabolismo Energético/efeitos dos fármacos , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , ATPases Mitocondriais Próton-Translocadoras/metabolismo , Miócitos Cardíacos/metabolismo , NAD/metabolismo , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Ratos , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos
9.
Life Sci ; 232: 116561, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31247208

RESUMO

AIMS: The poor prognosis of ovarian cancer is mainly caused by chemotherapy resistance. Studies show that the Bcl-2 inhibitor ABT737 can significantly improve the effect of cisplatin and induce mitochondrial pathway apoptosis. However, the mechanism of ABT737 increases sensitivity to cisplatin by regulating mitochondrial function remains unclear in ovarian cancer cells. Sirt3, as a histone deacetylase, is involved in the regulation of mitochondrial function in cancers. In this study, we intend to explore the mechanistic link between Sirt3 and mitochondrial dysfunction induced by ABT737 and cisplatin in ovarian cancer cells. MAIN METHODS: Apoptosis was examined by flow cytometry following Annexin V and PI staining. Sirt3 activity was assessed using Sirt3 deacetylase fluorometric assay. The mitochondrial membrane potential was examined by flow cytometry following JC-1 staining. Overexpression and knock-down of Sirt3 were confirmed by western blot analysis. Mitochondrial fission/fusion dynamics were detected by immunofluorescence staining or western blot analysis. KEY FINDINGS: Cisplatin accompanied with ABT737 promoted apoptosis and decreased mitochondrial membrane potential. ABT737 enhanced the sensitivity of ovarian cancer cells to cisplatin, which was partly achieved by activating Sirt3 to regulate the mitochondrial fission process. SIGNIFICANCE: This study identified the activation of Sirt3 played an important role in increasing sensitivity of ovarian cancer cells to cisplatin induced by ABT737. Furthermore, Sirt3 might represent a potential therapeutic target for ovarian cancer.


Assuntos
Compostos de Bifenilo/farmacologia , Nitrofenóis/farmacologia , Neoplasias Ovarianas/tratamento farmacológico , Sirtuína 3/metabolismo , Sulfonamidas/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica , Apoptose/efeitos dos fármacos , Carcinoma Epitelial do Ovário/tratamento farmacológico , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Cisplatino/metabolismo , Cisplatino/farmacologia , Feminino , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Dinâmica Mitocondrial/efeitos dos fármacos , Neoplasias Ovarianas/fisiopatologia , Ovário/metabolismo , Piperazinas/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos
10.
Food Funct ; 10(5): 2752-2765, 2019 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-31041965

RESUMO

Mitochondrial dysfunction contributed greatly to myocardial ischemia-reperfusion (MI/R)-induced cardiomyocyte apoptosis. Naringenin is a flavonoid exhibiting potential protective effects on myocardial mitochondria under stress conditions. However, the detailed down-stream signaling pathway involved remains uncovered. This study was designed to elucidate naringenin's mitochondrial protective actions during MI/R with a focus on AMPK-SIRT3 signaling. Sprague-Dawley rats were administered with naringenin (50 mg kg-1 d-1) and subjected to MI/R surgery in the presence or absence of compound C (0.25 mg kg-1, Com.C, an AMPK inhibitor) co-treatment. An in vitro study was performed on H9c2 cardiomyoblasts subjected to simulated ischemia-reperfusion treatment. Before the treatment, the cells were administered with naringenin (80 µmol L-1) with or without SIRT3 siRNA/AMPK1α siRNA transfection. Naringenin improved post-reperfusion left ventricular systolic pressure and the instantaneous first derivative of left ventricular pressure, and reduced the infarction size and myocardial apoptosis index by suppressing mitochondrial oxidative stress damage (as evidenced by decreased mitochondrial cytochrome c release and oxidative markers) and enhancing mitochondrial biogenesis [as evidenced by increased NRF1, TFAM and oxidative phosphorylation subunit complexes (II, III and IV)]. These protective actions were abolished by Com.C (in vivo) or SIRT3 siRNA (in vitro) administration. Further investigation revealed that Com.C (in vivo) or AMPK1α siRNA (in vitro) markedly suppressed PGC-1α and SIRT3 levels while SIRT3 siRNA (in vitro) inhibited SIRT3 expression without significantly changing AMPK phosphorylation and PGC-1α levels. Taken together, we found that naringenin directly inhibits mitochondrial oxidative stress damage and preserves mitochondrial biogenesis, thus attenuating MI/R injury. Importantly, AMPK-SIRT3 signaling played a key role in this process.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Flavanonas/administração & dosagem , Mitocôndrias/efeitos dos fármacos , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Sirtuína 3/metabolismo , Proteínas Quinases Ativadas por AMP/genética , Animais , Apoptose/efeitos dos fármacos , Citocromos c/metabolismo , Coração/efeitos dos fármacos , Humanos , Masculino , Mitocôndrias/metabolismo , Traumatismo por Reperfusão Miocárdica/genética , Traumatismo por Reperfusão Miocárdica/metabolismo , Miocárdio/metabolismo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Sirtuína 3/genética
11.
Oxid Med Cell Longev ; 2019: 4824035, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31093315

RESUMO

Background: The sedative anesthetic, propofol, is a cardioprotective agent for hyperglycemia-induced myocardial hypertrophy and dysfunction in rats. However, the specific protective mechanism has not been clarified. Methods and Results: In this experiment, we used H9c2 cells subjected to 22 mM glucose lasting for 72 hours as an in vitro model of cardiomyocyte injury by hyperglycemia and investigated the potential mechanism of propofol against hyperglycemic stress in cells. Propofol (5, 10, or 20 µM) was added to the cell cultures before and during the high glucose culture phases. Cell viability and levels of ROS were measured. The levels of proinflammatory cytokines were tested by ELISA. The levels of SIRT3, SOD2, PHD2, HIF-1α, Bcl-2, P53, and cleaved caspase-3 proteins were detected by western blotting. Our data showed that propofol attenuated high glucose-induced cell apoptosis accompanied by a decrease in the level of reactive oxygen species (ROS) and proinflammatory cytokines. Meanwhile, propofol decreased the apoptosis of H9c2 cells via increasing the expression of Bcl-2, SIRT3, SOD2, and PHD2 proteins and decreasing the expression of cleaved caspase-3, P53, and HIF-1α. Real-time PCR analysis showed that propofol did not significantly change the HIF-1α but increase PHD2 at mRNA level. HIF-1α silence significantly decreased apoptosis and inflammation in H9c2 cell during high glucose stress. Pretreatment of IOX2 (the inhibitor of PHD2) inhibited cell viability until the concentration reached 200 µM during high glucose stress. However, 50 µM TYP (the inhibitor of SIRT3) significantly inhibited cell viability during high glucose stress. Delayed IOX2 treatment for 6 hours significantly inhibited cell viability during high glucose stress. Conclusions: Propofol might alleviate cell apoptosis via SIRT3-HIF-1α axis during high glucose stress.


Assuntos
Apoptose/efeitos dos fármacos , Glucose/toxicidade , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Propofol/farmacologia , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Inflamação/patologia , Mediadores da Inflamação/metabolismo , Modelos Biológicos , Pró-Colágeno-Prolina Dioxigenase/genética , Pró-Colágeno-Prolina Dioxigenase/metabolismo , Substâncias Protetoras/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Espécies Reativas de Oxigênio/metabolismo , Sirtuína 3/genética , Sirtuína 3/metabolismo , Estresse Fisiológico/efeitos dos fármacos
12.
Oxid Med Cell Longev ; 2019: 4019619, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31110599

RESUMO

Bone mass loss around prostheses is a major cause of implant failure, especially in postmenopausal osteoporosis patients. In osteoporosis, excess oxidative stress largely contributed abnormal bone remodeling. Melatonin, which is synthesized from the pineal gland, promotes osteoblast differentiation and bone formation and has effectively been used to combat oxidative stress. Thus, we determined if melatonin can inhibit oxidative stress to promote osteogenesis and improve bone mass around prostheses in osteoporosis. In this study, we observed that received melatonin at 50 mg/kg body weight significantly increased periprosthetic bone mass as well as implant fixation intensity in ovariectomized (OVX) rats. Meanwhile, it decreased the expression of oxidative stress markers (NAPDH oxidase 2 and cytochrome c) and enhanced expressing level of the formation markers of bones (alkaline phosphatase, osteocalcin, and osterix) around prostheses compared to that in the control group. Additionally, melatonin decreased hydrogen peroxide- (H2O2-) induced oxidative stress and restored the osteogenesis potential of MC3T3-E1 cells. Mechanistically, melatonin clearly increased mitochondrial sirtuin 3 (SIRT3) expression and decreased the ratio of acetylated superoxide dismutase 2 (AC-SOD2)/SOD2 compared to the H2O2 group. SIRT3 inhibition counteracted the protective effects of melatonin on oxidative stress and bone formation. Together, the results showed that melatonin ameliorated oxidative stress in mitochondrial via the SIRT3/SOD2 signaling pathway, thereby promoting osteogenesis, improving bone mass around the prostheses, and increasing initial stability. Thus, melatonin might be a suitable candidate to decrease the rate of implant failure and lengthen the lifespan of prostheses after total joint arthroplasty.


Assuntos
Densidade Óssea/efeitos dos fármacos , Melatonina/uso terapêutico , Mitocôndrias/metabolismo , Sirtuína 3/metabolismo , Superóxido Dismutase/metabolismo , Animais , Feminino , Humanos , Melatonina/farmacologia , Estresse Oxidativo , Ratos , Ratos Sprague-Dawley , Transdução de Sinais
13.
Biomed Res Int ; 2019: 6803943, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31139646

RESUMO

During myocardial infarction, quickly opening the occluded coronary artery is a major method to save the ischemic myocardium. However, it also induces reperfusion injury, resulting in a poor prognosis. Alleviating the reperfusion injury improves the prognosis of the patients. Dihydromyricetin (DHM), a major component in the Ampelopsis grossedentata, has numerous biological functions. This study aims to clarify the effects of DHM under the ischemia/reperfusion (I/R) condition. We elucidated the role of Sirt3 in the cardiomyocyte response to DHM based on the hearts and primary cardiomyocytes. Cardiac function, mitochondrial biogenesis, and infarct areas were examined in the different groups. We performed Western blotting to detect protein expression levels after treatments. In an in vitro study, primary cardiomyocytes were treated with Hypoxia/Reoxygenation (H/R) to simulate the I/R. DHM reduced the infarct area and improved cardiac function. Furthermore, mitochondrial dysfunction was alleviated after DHM treatment. Moreover, DHM alleviated oxidative stress indicated by decreased ROS and MnSOD. However, the beneficial function of DHM was abolished after removing the Sirt3. On the other hand, the mitochondrial function was improved after DHM intervention in vitro study. Interestingly, Sirt3 downregulation inhibited the beneficial function of DHM. Therefore, the advantages of DHM are involved in the improvement of mitochondrial function and decreased oxidative stress through the upregulation of Sirt3. DHM offers a promising therapeutic avenue for better outcome in the patients with cardiac I/R injury.


Assuntos
Flavonóis/uso terapêutico , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/metabolismo , Sirtuína 3/metabolismo , Animais , Cardiotônicos/farmacologia , Cardiotônicos/uso terapêutico , Células Cultivadas , Proteínas de Ligação a DNA/metabolismo , Flavonóis/farmacologia , Proteínas de Grupo de Alta Mobilidade/metabolismo , Masculino , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/ultraestrutura , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Oxigênio
14.
J Biochem Mol Toxicol ; 33(8): e22337, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30958623

RESUMO

Elevated levels of saturated fatty acids show a strong cytotoxic effect in liver cells. Sirtuin 3 (SIRT3), a mitochondrially localized member of NAD+ -dependent deacetylase has been shown to protect hepatocytes against the oxidative stress. The role of SIRT3 on the cytotoxicity caused by fatty acids in liver cells is not fully understood. The aim of this study was to evaluate the expression level of SIRT3, oxidative stress, and mitochondrial impairments in human hepatoma HepG2 cells exposed to palmitic acid (PA). Our results showed that PA treatment caused the deposition of lipid droplets and resulted in an increased expression of tumor necrosis factor-α in a dose-dependent manner. Excessive accumulation of PA induces the reactive oxygen species formation and apoptosis while dissipating the mitochondrial transmembrane potential. The level of SIRT3 expression in both nuclear and mitochondrial fractions in HepG2 cells was decreased with the increase in PA concentrations. However, in the cytosolic fraction, the SIRT3 was undetectable. In conclusion, our results showed that PA caused an increase in inflammation and oxidative stress in HepG2 cells. The exposure of PA also resulted in the decline in transmembrane potential and an increase in apoptosis. The underexpression of nuclear and mitochondrial SIRT3 by PA suggests that the PA target the process that regulates the stress-related gene expression and mitochondrial functions.


Assuntos
Apoptose/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Mitocôndrias Hepáticas/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Ácido Palmítico/farmacologia , Sirtuína 3/metabolismo , Células Hep G2 , Humanos , Metabolismo dos Lipídeos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias Hepáticas/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
15.
Int Immunopharmacol ; 71: 361-371, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30952100

RESUMO

Trans sodium crocetinate (TSC) has been reported to exert a protective effect against cerebral ischemia/reperfusion (I/R) injury. However, whether TSC protects against myocardial ischemia/reperfusion (MI/R) injury remains unknown. Herein, we found that TSC treatment reduced myocardial infract size and elevated serum LDH and CK activities of MI/R rats. TSC administration attenuated oxidative stress in MI/R rats and H9C2 cells exposed to oxygen glucose deprivation/reperfusion (OGD/R). TSC administration relieved I/R-induced myocardial apoptosis in vivo and in vitro, as evidenced by reduced number of TUNEL positive cells, accompanying with marked decreases in caspase-3 activity and Bax protein level and an increase in Bcl-2 protein level. TSC treatment markedly increased SIRT3 activity and SIRT3 and SOD2 protein levels, and could also diminished the phosphorylation of FOXO3a protein. Additionally, TSC treatment attenuated the acetylation of FOXO3a and SOD2 protein. But, these effects were obviously blocked by SIRT3 knockdown. Besides, SIRT3 knockdown blocked the cardioprotective effect of TSC on OGD/R-induced oxidative stress, apoptosis and mitochondrial dysfunction in vitro. In summary, TSC alleviates I/R-induced myocardial oxidative stress and apoptosis via the SIRT3/FOXO3a/SOD2 signaling pathway. Our study suggests that TSC may become a novel drug for the treatment of MI/R injury.


Assuntos
Antioxidantes/uso terapêutico , Carotenoides/uso terapêutico , Infarto do Miocárdio/tratamento farmacológico , Miocárdio/metabolismo , Traumatismo por Reperfusão/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Oclusão Coronária , Modelos Animais de Doenças , Proteína Forkhead Box O3/metabolismo , Humanos , Masculino , Estresse Oxidativo/efeitos dos fármacos , RNA Interferente Pequeno/genética , Ratos , Ratos Wistar , Transdução de Sinais , Sirtuína 3/genética , Sirtuína 3/metabolismo
16.
Nat Commun ; 10(1): 1886, 2019 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-31015456

RESUMO

Intermittent food deprivation (fasting, IF) improves mood and cognition and protects neurons against excitotoxic degeneration in animal models of epilepsy and Alzheimer's disease (AD). The mechanisms by which neuronal networks adapt to IF and how such adaptations impact neuropathological processes are unknown. We show that hippocampal neuronal networks adapt to IF by enhancing GABAergic tone, which is associated with reduced anxiety-like behaviors and improved hippocampus-dependent memory. These neuronal network and behavioral adaptations require the mitochondrial protein deacetylase SIRT3 as they are abolished in SIRT3-deficient mice and wild type mice in which SIRT3 is selectively depleted from hippocampal neurons. In the AppNL-G-F mouse model of AD, IF reduces neuronal network hyperexcitability and ameliorates deficits in hippocampal synaptic plasticity in a SIRT3-dependent manner. These findings demonstrate a role for a mitochondrial protein deacetylase in hippocampal neurons in behavioral and GABAergic synaptic adaptations to IF.


Assuntos
Doença de Alzheimer/dietoterapia , Jejum/fisiologia , Neurônios GABAérgicos/metabolismo , Hipocampo/fisiologia , Sirtuína 3/metabolismo , Doença de Alzheimer/genética , Precursor de Proteína beta-Amiloide/genética , Animais , Comportamento Animal/fisiologia , Cognição/fisiologia , Excitabilidade Cortical/fisiologia , Modelos Animais de Doenças , Hipocampo/citologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mitocôndrias/metabolismo , Rede Nervosa/fisiologia , Plasticidade Neuronal/fisiologia , Estresse Oxidativo/fisiologia , Sirtuína 3/genética , Superóxido Dismutase/genética
17.
BMC Bioinformatics ; 20(Suppl 2): 104, 2019 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-30871457

RESUMO

BACKGROUND: Gene co-expression studies can provide important insights into molecular and cellular signaling pathways. The GeneNetwork database is a unique resource for co-expression analysis using data from a variety of tissues across genetically distinct inbred mice. However, extraction of biologically meaningful co-expressed gene sets is challenging due to variability in microarray platforms, probe quality, normalization methods, and confounding biological factors. In this study, we tested whether literature derived functional cohesion could be used as an objective metric in lieu of 'ground truth' to evaluate the quality of probes and microarray datasets. RESULTS: We examined Sirtuin-3 (Sirt3) co-expressed gene sets extracted from either liver or brain tissues of BXD recombinant inbred mice in the GeneNetwork database. Depending on the microarray platform, there were as many as 26 probes that targeted different regions of Sirt3 primary transcript. Co-expressed gene sets (ranging from 100-1000 genes) associated with each Sirt3 probe were evaluated using the previously developed literature-derived cohesion p-value (LPv) and benchmarked against 'gold standards' derived from proteomic studies or Gene Ontology classifications. We found that the maximal F-measure was obtained at an average window size of 535 genes. Using set size of 500 genes, the Pearson correlations between LPv and F-measure as well as between LPv and mitochondrial gene enrichment p-values were 0.90 and 0.93, respectively. Importantly, we found that the LPv approach can distinguish high quality Sirt3 probes. Analysis of the most functionally cohesive Sirt3 co-expressed gene set revealed core metabolic pathways that were shared between hippocampus and liver as well as distinct pathways which were unique to each tissue. These results are consistent with other studies that suggest Sirt3 is a key metabolic regulator and has distinct functions in energy-producing vs. energy-demanding tissues. CONCLUSIONS: Our results provide proof-of-concept that literature cohesion analysis is useful for evaluating the quality of probes and microarray datasets, particularly when experimentally derived gold standards are unavailable. Our approach would enable researchers to rapidly identify biologically meaningful co-expressed gene sets and facilitate discovery from high throughput genomic data.


Assuntos
Mineração de Dados/métodos , Perfilação da Expressão Gênica/métodos , Proteômica/métodos , Sirtuína 3/metabolismo , Humanos
18.
BMC Endocr Disord ; 19(1): 19, 2019 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-30736780

RESUMO

BACKGROUND: Sirtuin 1 (SIRT1) and sirtuin 3 (SIRT3) proteins have an important role in counteracting oxidative stress. Although diabetes and hypothyroidism (HT) are both characterized by oxidative stress, the mechanisms are not fully understood. This study investigated the effects of type 1 diabetes (T1D), type 2 diabetes (T2D), and HT on the expression levels of SIRT1, SIRT3, and manganese superoxide dismutase (SOD2). METHODS: Gene expression of SIRT1, SIRT3, and SOD2 was measured using real-time PCR. The protein expression of SOD2 and lipid peroxidation (thiobarbituric acid reactive substances) was measured by the TBARS Assay kit and enzyme-linked immunosorbent assay (ELISA) respectively. RESULTS: The results showed that the SIRT1 and SIRT3 levels were lower in peripheral blood samples from patients with T1D, T2D, or HT than in healthy individuals. Interestingly, the mRNA and protein expression levels of SOD2 were higher in all three patient groups. Lipid peroxidation was higher in the patients with HT than in the healthy individuals. CONCLUSIONS: These results indicate alterations in the expression levels of sirtuins and superoxide dismutase in diabetes and HT, which may be related, at least in part, to the oxidative stress. Identifying such alterations in those patients will pave the way towards the development of drugs to enhance SIRT1 and SIRT3 expression and their activity to prevent the damaging effect of oxidative stress.


Assuntos
Biomarcadores/análise , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Hipotireoidismo/metabolismo , Sirtuína 1/metabolismo , Sirtuína 3/metabolismo , Superóxido Dismutase/metabolismo , Adulto , Estudos de Casos e Controles , Diabetes Mellitus Tipo 1/patologia , Diabetes Mellitus Tipo 2/patologia , Feminino , Seguimentos , Humanos , Hipotireoidismo/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico
19.
ChemMedChem ; 14(8): 853-864, 2019 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-30811852

RESUMO

Indoles are privileged structures in medicinal and bioorganic chemistry that are particularly well suited to serve as platforms for diversity. Among many other therapeutic areas, the indole scaffold has been used to design aromatic compounds useful to interfere with enzymes engaged in the regulation of substrate acylation status, such as sirtuins. However, the planarity of the indole ring is not necessarily optimal for all target enzymes, especially when functionalization with aromatic side chains is required. Replacement of flat scaffolds by nonplanar molecular cores dominated by sp3 hybridization is a common strategy to avoid the disadvantages associated with poor solubility and high promiscuity, while covering less-well-explored areas of chemical space. Thus, we synthesized fragment-like tetrahydroindoles suitable for fragment-based drug discovery as well as a well-characterized small library intended as multipurpose screening compounds. For proof of principle, these compounds were screened against sirtuins 1-3, enzymes known to be addressable by indoles. We found that 2,6,6-trimethyl-4-oxo-4,5,6,7-tetrahydro-1H-indole-3-carboxamides are potent and selective SIRT2 inhibitors. Compound 16 t displayed an IC50 value of 0.98 µm and could serve as exquisite starting point for hit-to-lead profiling.


Assuntos
Inibidores de Histona Desacetilases/química , Indóis/química , Sirtuína 2/antagonistas & inibidores , Sítios de Ligação , Domínio Catalítico , Inibidores de Histona Desacetilases/síntese química , Inibidores de Histona Desacetilases/metabolismo , Humanos , Indóis/síntese química , Indóis/metabolismo , Concentração Inibidora 50 , Simulação de Acoplamento Molecular , Sirtuína 1/antagonistas & inibidores , Sirtuína 1/metabolismo , Sirtuína 2/metabolismo , Sirtuína 3/antagonistas & inibidores , Sirtuína 3/metabolismo , Relação Estrutura-Atividade
20.
Biochim Biophys Acta Mol Basis Dis ; 1865(6): 1389-1401, 2019 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-30771486

RESUMO

Methylglyoxal (MG), a highly reactive dicarbonyl derived from metabolic processes, is the most powerful precursor of advanced glycation end products (AGEs). Glycative stress has been recently associated with ovarian dysfunctions in aging and PCOS syndrome. We have investigated the role of the NAD+-dependent Class III deacetylase SIRT1 in the adaptive response to MG in mouse oocytes and ovary. In mouse oocytes, MG induced up-expression of glyoxalase 1 (Glo1) and glyoxalase 2 (Glo2) genes, components of the main MG detoxification system, whereas inhibition of SIRT1 by Ex527 or sirtinol reduced this response. In addition, the inhibition of SIRT1 worsened the effects of MG on oocyte maturation rates, while SIRT1 activation by resveratrol counteracted MG insult. Ovaries from female mice receiving 100 mg/kg MG by gastric administration for 28 days (MG mice) exhibited increased levels of SIRT1 along with over-expression of catalase, superoxide dismutase 2, SIRT3, PGC1α and mtTFA. Similar levels of MG-derived AGEs were observed in the ovaries from MG and control groups, along with enhanced protein expression of glyoxalase 1 in MG mice. Oocytes ovulated by MG mice exhibited atypical meiotic spindles, a condition predisposing to embryo aneuploidy. Our results from mouse oocytes revealed for the first time that SIRT1 could modulate MG scavenging by promoting expression of glyoxalases. The finding that up-regulation of glyoxalase 1 is associated with that of components of a SIRT1 functional network in the ovaries of MG mice provides strong evidence that SIRT1 participates in the response to methylglyoxal-dependent glycative stress in the female gonad.


Assuntos
Produtos Finais de Glicação Avançada/genética , Oócitos/efeitos dos fármacos , Ovário/efeitos dos fármacos , Aldeído Pirúvico/farmacologia , Sirtuína 1/genética , Animais , Benzamidas/farmacologia , Carbazóis/farmacologia , Catalase/genética , Catalase/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Inibidores Enzimáticos/farmacologia , Feminino , Regulação da Expressão Gênica , Produtos Finais de Glicação Avançada/metabolismo , Lactoilglutationa Liase/antagonistas & inibidores , Lactoilglutationa Liase/genética , Lactoilglutationa Liase/metabolismo , Camundongos , Camundongos Endogâmicos , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Naftóis/farmacologia , Oócitos/citologia , Oócitos/metabolismo , Ovário/citologia , Ovário/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Cultura Primária de Células , Aldeído Pirúvico/antagonistas & inibidores , Resveratrol/farmacologia , Transdução de Sinais , Sirtuína 1/metabolismo , Sirtuína 3/genética , Sirtuína 3/metabolismo , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Tioléster Hidrolases/antagonistas & inibidores , Tioléster Hidrolases/genética , Tioléster Hidrolases/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
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