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1.
Life Sci ; 259: 118375, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32891612

RESUMO

OBJECTIVE: Short-chain fatty acids were reported to be the precursors of milk fat and can stimulate the de novo synthesis of fatty acids in bovine mammary epithelial cells (bMECs). However, the mechanism has not been elucidated. The purpose of this study was to investigate the effects of sodium butyrate (NaB) on milk fat synthesis in bMECs and explore its potential mechanism. METHODS: Bovine mammary epithelial cells (bMECs) were isolated for subsequent experimental uses. BODIPY staining and triglyceride kit were used to detect the milk fat synthesis in bMECs. Western blotting and RT-PCR assays were performed to detect the expression of related genes in bMECs. Immunoprecipitation was used to detect the acetylation of SREBP1 in bMECs. RESULTS: The results showed that NaB significantly promoted milk fat synthesis, promoted the activity of mechanistic target of rapamycin (mTOR) and S6 kinase (S6K), inhibited the activity of AMP-activated protein kinase (AMPK), and promoted the gene expression of G protein-coupled receptor 41 (GPR41). Knockdown of GPR41 and sterol regulatory element binding protein 1 (SREBP1) and overexpression of sirtuin1 (SIRT1), mTOR inhibitor (rapamycin), and AMPK activator (AICIR) eliminated these effects. These results indicated that NaB increased the nuclear translocation of SREBP1 via the GPR41/AMPK/mTOR/S6K signalling pathway, promoted the acetylation of mature SREBP1a via GPR41/AMPK/SIRT1, and then promoted milk fat synthesis. CONCLUSION: Taken together, these results demonstrated that NaB increased nuclear translocation and acetylation of SREBP1 to promote milk fat synthesis by activating GPR41 and its downstream signalling pathways.


Assuntos
Ácido Butírico/farmacologia , Glicolipídeos/biossíntese , Glicoproteínas/biossíntese , Glândulas Mamárias Animais/efeitos dos fármacos , Receptores Acoplados a Proteínas-G/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Western Blotting , Carbazóis , Bovinos , Células Cultivadas , Feminino , Imunoprecipitação , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Glândulas Mamárias Animais/metabolismo , Naftalenos , Reação em Cadeia da Polimerase em Tempo Real , Sirtuína 1/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo
2.
Mol Cell ; 79(5): 846-856.e8, 2020 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-32755594

RESUMO

Resveratrol is a natural product associated with wide-ranging effects in animal and cellular models, including lifespan extension. To identify the genetic target of resveratrol in human cells, we conducted genome-wide CRISPR-Cas9 screens to pinpoint genes that confer sensitivity or resistance to resveratrol. An extensive network of DNA damage response and replicative stress genes exhibited genetic interactions with resveratrol and its analog pterostilbene. These genetic profiles showed similarity to the response to hydroxyurea, an inhibitor of ribonucleotide reductase that causes replicative stress. Resveratrol, pterostilbene, and hydroxyurea caused similar depletion of nucleotide pools, inhibition of replication fork progression, and induction of replicative stress. The ability of resveratrol to inhibit cell proliferation and S phase transit was independent of the histone deacetylase sirtuin 1, which has been implicated in lifespan extension by resveratrol. These results establish that a primary impact of resveratrol on human cell proliferation is the induction of low-level replicative stress.


Assuntos
Proliferação de Células/efeitos dos fármacos , Replicação do DNA/efeitos dos fármacos , Resveratrol/farmacologia , Sistemas CRISPR-Cas , Linhagem Celular , Resistência a Medicamentos/genética , Humanos , Hidroxiureia/farmacologia , Células Jurkat , Nucleotídeos/metabolismo , Pontos de Checagem da Fase S do Ciclo Celular/efeitos dos fármacos , Sirtuína 1/metabolismo , Estilbenos/farmacologia
3.
Life Sci ; 258: 118030, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32739470

RESUMO

The risk of atherosclerosis (AS) ascends among post-menopausal women, while current hormone replacement therapy exerts several adverse effects. Alisol B 23-acetate (AB23A), a tetracyclic triterpenoid isolated from the rhizome of Alisma orientale, was reported to show multiple physiological activities, including regulating lipid metabolism. According to molecular docking analysis, it was predicted to bind with estrogen receptor α (ERα). In this study, we aimed to observe the effect of AB23A on preventing post-menopausal AS and explore whether the mechanism was mediated by ERα. In vitro, free fatty acid (FFA) was applied to induce the abnormal lipid metabolism of L02 cells. In vivo, the ApoE-/- mice were ovariectomized to mimic the cessation of estrogen. The high-fat diet was also given to induce post-menopausal AS. We demonstrated AB23A attenuated the accumulation of total cholesterol and triglyceride induced by free fatty acids in hepatocytes. In high-fat diet-ovariectomy-treated ApoE-/- mice, AB23A eliminated lipids in blood and liver. AB23A not only reduced the synthesis of proprotein convertase subtilisin/kexin type 9 (PCSK9) through sterol-regulatory element binding proteins (SREBPs) but also suppressed the secretion of PCSK9 through silent information regulator 1 (SIRT1). Notably, AB23A promoted the expression of ERα in vivo and in vitro. The both ERα inhibitor and ERα siRNA were also applied in confirming whether the hepatic protective effect of AB23A was mediated by ERα. We found that AB23A significantly promoted the expression of ERα. AB23A could inhibit the synthesis and secretion of PCSK9 through ERα, lower the accumulation of triglyceride and cholesterol, and prevent post-menopausal AS.


Assuntos
Aterosclerose/patologia , Colestenonas/farmacologia , Receptor alfa de Estrogênio/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Pós-Menopausa/efeitos dos fármacos , Animais , Aterosclerose/genética , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Colestenonas/química , Dieta Hiperlipídica , Ácidos Graxos/metabolismo , Feminino , Lipoproteínas LDL/metabolismo , Camundongos , Ovariectomia , Regiões Promotoras Genéticas/genética , Pró-Proteína Convertase 9/genética , Pró-Proteína Convertase 9/metabolismo , Receptores de LDL/genética , Receptores de LDL/metabolismo , Sirtuína 1/metabolismo , Proteínas de Ligação a Elemento Regulador de Esterol/genética , Proteínas de Ligação a Elemento Regulador de Esterol/metabolismo , Regulação para Cima/efeitos dos fármacos
4.
Life Sci ; 257: 118120, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32693244

RESUMO

AIMS: Catalpol (Cat) can ameliorate oxide stress and inflammation caused by diabetic nephropathy (DN), but the molecular mechanisms are unclear. This study was designed to investigate the anti-diabetic effects of Cat and its potential mechanism. MAIN METHODS: We constructed high-fat diet/streptozotocin (HFD/STZ)-induced DN mice and high glucose (HG)-induced podocyte model. The hypoglycemic effect of Cat was analyzed by general features of DN mice. Kidney function was detected via ELISA assay and Western blotting. Renal histopathology analysis was conducted via hematoxylin and eosin (H&E), Masson and periodic acid-silver metheramine (PASM) staining. Cellular viability was measured by TUNEL assay. In order to further study the potential mechanisms of Cat, various proteins in AMPK/SIRT1/NF-κB pathway were detected in DN mice and podocytes with siRNA-AMPK intervention using Western blotting, respectively. KEY FINDINGS: We found hyperglycemia, renal structural and function abnormalities, and increased renal inflammation in DN mice. However, Cat effectively attenuated kidney damage caused by inflammation and increased AMPK, p-AMPK and SIRT1 levels. After AMPK-siRNA transfected into HG-induced podocyte model, AMPK, p-AMPK and SIRT1 levels were obviously decreased, while Cat reversed these chandes. The levels of p-NF-κB, ASC, Cleaved IL-1ß, NLRP3, Cleaved caspase1 and GSDMD-N significantly decreased by Cat treatment both in DN mice and podocyte model, which indicated that Cat could activate AMPK/SIRT1/NF-κB pathway. SIGNIFICANCE: Cat could effectively inhibit oxide stress and inflammation accompanied with pyroptosis and its mechanism might be related to AMPK/SIRT1/NF-κB pathway, indicating that Cat possessed potential value in the treatment of DN.


Assuntos
Nefropatias Diabéticas/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Glucosídeos Iridoides/uso terapêutico , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Western Blotting , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/tratamento farmacológico , Nefropatias Diabéticas/patologia , Ensaio de Imunoadsorção Enzimática , Rim/efeitos dos fármacos , Rim/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Sirtuína 1/metabolismo
5.
Life Sci ; 257: 118116, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32702447

RESUMO

Emerging evidence implicates accelerated renal tubular epithelial cell (RTEC) senescence in renal fibrosis progression. Mitophagy protects against kidney injury. However, the mechanistic interplay between cell senescence and mitophagy in RTECs is not clearly defined. The purpose of this study was to evaluate the inhibition of RTEC senescence and renal fibrosis by quercetin and explore the underlying mechanisms. We found that quercetin attenuated RTEC senescence induced by angiotensin II (AngII) in vitro and unilateral ureteral obstruction in vivo. Moreover, we demonstrated that mitochondrial abnormalities such as elevated reactive oxygen species, decreased membrane potential, and fragmentation and accumulation of mitochondrial mass, occurred in AngII-treated RTECs. Quercetin treatment reversed these effects. Furthermore, quercetin enhanced mitophagy in AngII-treated RTECs, which was markedly reduced by treatment with mitophagy-specific inhibitors. Sirtuin-1 (SIRT1) was involved in quercetin-mediated PTEN-induced kinase 1 (PINK1)/Parkin-associated mitophagy activation. Pharmacological antagonism of SIRT1 in AngII-treated RTECs blocked the effects of quercetin on mitophagy and cellular senescence. Finally, quercetin alleviated kidney fibrosis by reducing RTEC senescence via mitophagy. Collectively, the antifibrotic effect of quercetin involved inhibition of RTEC senescence, possibly through activation of SIRT1/PINK1/Parkin-mediated mitophagy. These findings suggest that pharmacological elimination of senescent cells and stimulation of mitophagy represent effective therapeutic strategies to prevent kidney fibrosis.


Assuntos
Antioxidantes/farmacologia , Senescência Celular/efeitos dos fármacos , Túbulos Renais Proximais/efeitos dos fármacos , Rim/patologia , Mitofagia/efeitos dos fármacos , Proteínas Quinases/metabolismo , Quercetina/farmacologia , Sirtuína 1/metabolismo , Animais , Antioxidantes/uso terapêutico , Linhagem Celular , Epitélio/efeitos dos fármacos , Fibrose , Citometria de Fluxo , Rim/efeitos dos fármacos , Túbulos Renais Proximais/patologia , Quercetina/uso terapêutico , Ratos
6.
Am J Physiol Renal Physiol ; 319(2): F335-F344, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32657157

RESUMO

Human immunodeficiency virus (HIV) infection of kidney cells can lead to HIV-associated nephropathy (HIVAN) and aggravate the progression of other chronic kidney diseases. Thus, a better understanding of the mechanisms of HIV-induced kidney cell injury is needed for effective therapy against HIV-induced kidney disease progression. We have previously shown that the acetylation and activation of key inflammatory regulators, NF-κB p65 and STAT3, were increased in HIVAN kidneys. Here, we demonstrate the key role of sirtuin 1 (SIRT1) deacetylase in the regulation of NF-κB and STAT3 activity in HIVAN. We found that SIRT1 expression was reduced in the glomeruli of human and mouse HIVAN kidneys and that HIV-1 gene expression was associated with reduced SIRT1 expression and increased acetylation of NF-κB p65 and STAT3 in cultured podocytes. Interestingly, SIRT1 overexpression, in turn, reduced the expression of negative regulatory factor in podocytes stably expressing HIV-1 proviral genes, which was associated with inactivation of NF-κB p65 and a reduction in HIV-1 long terminal repeat promoter activity. In vivo, the administration of the small-molecule SIRT1 agonist BF175 or inducible overexpression of SIRT1 specifically in podocytes markedly attenuated albuminuria, kidney lesions, and expression of inflammatory markers in Tg26 mice. Finally, we showed that the reduction in SIRT1 expression by HIV-1 is in part mediated through miR-34a expression. Together, our data provide a new mechanism of SIRT1 regulation and its downstream effects in HIV-1-infected kidney cells and indicate that SIRT1/miR-34a are potential drug targets to treat HIV-related kidney disease.


Assuntos
Nefropatia Associada a AIDS/virologia , Insuficiência Renal Crônica/metabolismo , Sirtuína 1/metabolismo , Nefropatia Associada a AIDS/complicações , Nefropatia Associada a AIDS/metabolismo , Animais , Humanos , Rim/metabolismo , Glomérulos Renais/metabolismo , Glomérulos Renais/virologia , Camundongos , Podócitos/metabolismo , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/patologia , Insuficiência Renal Crônica/virologia , Fator de Transcrição RelA/metabolismo
7.
Mol Pharmacol ; 98(2): 88-95, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32487734

RESUMO

Arylamine N-acetyltransferase 1 (NAT1) is a phase II xenobiotic-metabolizing enzyme that also has a role in cancer cell growth and metabolism. Recently, it was reported that NAT1 undergoes lysine acetylation, an important post-translational modification that can regulate protein function. In the current study, we use site-directed mutagenesis to identify K100 and K188 as major sites of lysine acetylation in the NAT1 protein. Acetylation of ectopically expressed NAT1 in HeLa cells was decreased by C646, an inhibitor of the protein acetyltransferases p300/CREB-binding protein (CBP). Recombinant p300 directly acetylated NAT1 in vitro. Acetylation of NAT1 was enhanced by the sirtuin (SIRT) inhibitor nicotinamide but not by the histone deacetylase inhibitor trichostatin A. Cotransfection of cells with NAT1 and either SIRT 1 or 2, but not SIRT3, significantly decreased NAT1 acetylation. NAT1 activity was evaluated in cells after nicotinamide treatment to enhance acetylation or cotransfection with SIRT1 to inhibit acetylation. The results indicated that NAT1 acetylation impaired its enzyme kinetics, suggesting decreased acetyl coenzyme A binding. In addition, acetylation attenuated the allosteric effects of ATP on NAT1. Taken together, this study shows that NAT1 is acetylated by p300/CBP in situ and is deacetylated by the sirtuins SIRT1 and 2. It is hypothesized that post-translational modification of NAT1 by acetylation at K100 and K188 may modulate NAT1 effects in cells. SIGNIFICANCE STATEMENT: There is growing evidence that arylamine N-acetyltransferase 1 has an important cellular role in addition to xenobiotic metabolism. Here, we show that NAT1 is acetylated at K100 and K188 and that changes in protein acetylation equilibrium can modulate its activity in cells.


Assuntos
Arilamina N-Acetiltransferase/química , Arilamina N-Acetiltransferase/metabolismo , Proteína de Ligação a CREB/genética , Proteína p300 Associada a E1A/genética , Isoenzimas/química , Isoenzimas/metabolismo , Sirtuína 1/genética , Sirtuína 2/genética , Acetilcoenzima A/metabolismo , Acetilação/efeitos dos fármacos , Arilamina N-Acetiltransferase/genética , Benzoatos/farmacologia , Proteína de Ligação a CREB/metabolismo , Cristalografia por Raios X , Proteína p300 Associada a E1A/metabolismo , Células HeLa , Humanos , Ácidos Hidroxâmicos/farmacologia , Isoenzimas/genética , Lisina/química , Lisina/genética , Modelos Moleculares , Mutagênese Sítio-Dirigida , Niacinamida/farmacologia , Conformação Proteica , Pirazóis/farmacologia , Sirtuína 1/metabolismo , Sirtuína 2/metabolismo , Transfecção
8.
Chem Biol Interact ; 327: 109180, 2020 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-32569592

RESUMO

Testicular damage contributes to cyclosporine A (CsA) induced male infertility. However, the exact underlying molecular mediators involved in CsA-induced testis disorder remains unclear. The present study aimed to characterize the role of mir-34a/sirt-1 in CsA induced testicular injury alone or in combination with curcumin. A total of twenty-eight male Wistar rats were subdivided into four groups: control (Con), sham, cyclosporine A (CsA), cyclosporineA + curcumin (CsA + cur). The animals received cyclosporine A (30 mg/kg) and curcumin (40 mg/kg) for 28 days by oral gavage. At the end of the experiment, CsA administration significantly resulted in a decrease in testis weight and testis coefficient. The molecular analysis demonstrated that CsA exposure increased 8-OHdg and Nox4 protein contents in the testis tissue. TUNEL staining indicated that CsA caused the number of apoptotic cells to increase in the testes of male rats. In addition, exposure to CsA resulted in an increased expression of Bax, and a decreased expresion in that of Bcl-2, with a concomitant up-regulation of the Bax/Bcl-2, c-Caspase-3/p-Caspase-3 ratio and cytochrome c level. Meanwhile, exposure to CsA increased the expression of mir-34a and decreased sirt-1 protein level in the testis tissue samples compared to the control group. Taken together, our findings suggested that CsA can cause damage to testicular germ cells via oxidative stress and mitochondrial apoptotic pathway, and probably mir-34a/sirt-1 play a crucial role in this process. It also demonstrates that these negative effects of CsA can be reduced by using curcumin as an antioxidant and anti-inflammatory agent.


Assuntos
Apoptose/efeitos dos fármacos , Curcumina/uso terapêutico , Ciclosporina/toxicidade , MicroRNAs/metabolismo , Sirtuína 1/metabolismo , Doenças Testiculares/tratamento farmacológico , 8-Hidroxi-2'-Desoxiguanosina/metabolismo , Animais , Anti-Inflamatórios não Esteroides/uso terapêutico , Antioxidantes/uso terapêutico , Citocromos c/metabolismo , Expressão Gênica/efeitos dos fármacos , Masculino , Tamanho do Órgão/efeitos dos fármacos , Estresse Oxidativo , Ratos Wistar , Doenças Testiculares/induzido quimicamente , Testículo/efeitos dos fármacos , Testículo/patologia
9.
Life Sci ; 256: 117990, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32574665

RESUMO

AIM: Luteolin and lycopene are common natural products, widely existing in nature, and both of which were reported to have various biological functions including anti-inflammatory, anti-obesity and anti-NAFLD. In the present study, we aimed to evaluate the therapeutic efficacy of luteolin and lycopene in combination and its latent molecular mechanisms in vitro and in vivo models of NAFLD. MAIN METHODS: Sodium palmitate (PA)-induced steatotic HepG2 cells and primary hepatocytes, and high-fat diet-induced C57BL/6J obese mice were treated with luteolin, lycopene and their combination. Metabolic parameters were measured. KEY FINDINGS: We found that luteolin (20 µM) + lycopene (10 µM) was the best therapeutic combination in PA-induced HepG2 cells, and significantly improve cell viability and lipid accumulation in PA-induced HepG2 cells and primary hepatocytes. In addition, luteolin (20 mg/kg) + lycopene (20 mg/kg) could ameliorate increased body weight and hepatocyte steatosis; regulate serum triglycerides, serum total cholesterol, hepatic triglycerides and hepatic total cholesterol; decrease serum alanine transaminase and aspartate transaminase. Furthermore, in vivo and in vitro, luteolin, lycopene and their combination had no effect on Sirt1 expression, but all of them could upregulate the expression of NAMPT, which could increase the level of NAD+, the co-substrate of Sirt1, indirectly activating Sirt1/AMPK pathway, and then inhibited lipogenesis and increased ß-oxidation, defensing the "first hit"; they also inactivated nuclear factor-κB (NF-κB) and decreased the levels of IL-6, IL-1ß and TNF-α, defensing the "second hit". SIGNIFICANCE: Thus, luteolin and lycopene in combination can effectively ameliorate "two-hit" in NAFLD through activation of the Sirt1/AMPK pathway.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Luteolina/administração & dosagem , Licopeno/administração & dosagem , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Sirtuína 1/metabolismo , Animais , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Células Cultivadas , Dieta Hiperlipídica/efeitos adversos , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Células Hep G2 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/etiologia , Substâncias Protetoras/administração & dosagem , Distribuição Aleatória
10.
Life Sci ; 256: 117898, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32522566

RESUMO

BACKGROUND: Atherosclerosis as a progressive inflammatory disease is the main cause of Coronary Artery Disease (CAD). Multiple genetic and environmental factors are involved in susceptibility to atherosclerotic vascular diseases. FOXO1 gene acts as a key molecular proinflammatory transcription factor and the FBOX32 gene as an F-box protein plays pivotal roles in regulation of muscle atrophy and inhibition of the pathologic cardiac hypertrophy. MiR-27a has been reported to contribute to atherosclerosis prevention and the inflammatory processes of atherosclerosis. MicroRNA-23a has been found to promote atherosclerotic plaque progression and vulnerability. Hence, given the importance of these subjects, the present study was carried out to investigate the expression levels of the desired genes. METHODOLOGY: In this case-control study, 82 patients with CAD and 80 healthy controls were investigated. Expression levels of miRNAs -27a and 23a, FOXO1, Sirtuin 1 (SIRT1) in the Peripheral Blood Mononuclear Cells (PBMCs), serum concentration of IL6 and TNF-α of the studied subjects were evaluated using the real-time Polymerase Chain Reaction (PCR) technique. The correlation between the variables was also investigated. RESULTS: Results of the study demonstrated that expression of FOXO1, IL-6, TNF-α, miR-27a, and miR-23a increased in the PBMCs of the patients with CAD and their expression levels were significantly correlated with the severity of stenosis. A significant decrease was observed in the expression of SIRT1 in the patients with CAD compared to the healthy controls. Furthermore, the Receiver Operating Characteristic (ROC) curve was plotted to find the effectiveness of FOXO1 and miRNA-27a gene expression as a diagnostic marker for CAD. CONCLUSIONS: Findings of the study suggested that miRs-27a and FOXO1 genes have a potential role in the progression of atherosclerosis and mediate the molecular and genetic disturbances of the intracellular communication in the atherosclerosis.


Assuntos
Doença da Artéria Coronariana/sangue , Citocinas/sangue , Proteína Forkhead Box O1/metabolismo , Regulação da Expressão Gênica , Mediadores da Inflamação/sangue , Leucócitos Mononucleares/metabolismo , MicroRNAs/sangue , Estudos de Casos e Controles , Doença da Artéria Coronariana/genética , Feminino , Proteína Forkhead Box O1/genética , Humanos , Modelos Lineares , Masculino , MicroRNAs/genética , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Sirtuína 1/genética , Sirtuína 1/metabolismo
11.
Mol Cell ; 78(5): 805-807, 2020 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-32502419

RESUMO

The amplitude of circadian rhythms dampens with age, but Levine et al. (2020) now show that nicotinamide adenine dinucleotide (NAD+) can restore robust circadian gene expression and behavior in aged mice through SIRT1-dependent deacetylation of the core clock protein PER2.


Assuntos
Ritmo Circadiano/genética , Proteínas Circadianas Period/metabolismo , Fatores de Transcrição ARNTL/genética , Fatores Etários , Animais , Relógios Circadianos/fisiologia , Ritmo Circadiano/fisiologia , Citocinas/metabolismo , Humanos , Camundongos , NAD/metabolismo , Proteínas Circadianas Period/genética , Sirtuína 1/metabolismo , Sirtuínas/metabolismo
12.
Mol Cell Endocrinol ; 515: 110917, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32593740

RESUMO

Obesity patients are more susceptible to develop COVID-19 severe outcome due to the role of angiotensin-converting enzyme 2 (ACE2) in the viral infection. ACE2 is regulated in the human cells by different genes associated with increased (TLR3, HAT1, HDAC2, KDM5B, SIRT1, RAB1A, FURIN and ADAM10) or decreased (TRIB3) virus replication. RNA-seq data revealed 14857 genes expressed in human subcutaneous adipocytes, including genes mentioned above. Irisin treatment increased by 3-fold the levels of TRIB3 transcript and decreased the levels of other genes. The decrease in FURIN and ADAM10 expression enriched diverse biological processes, including extracellular structure organization. Our results, in human subcutaneous adipocytes cell culture, indicate a positive effect of irisin on the expression of multiple genes related to viral infection by SARS-CoV-2; furthermore, translatable for other tissues and organs targeted by the novel coronavirus and present, thus, promising approaches for the treatment of COVID-19 infection as therapeutic strategy to decrease ACE2 regulatory genes.


Assuntos
Adipócitos/efeitos dos fármacos , Fibronectinas/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Proteína ADAM10/genética , Proteína ADAM10/metabolismo , Adipócitos/citologia , Adipócitos/metabolismo , Secretases da Proteína Precursora do Amiloide/genética , Secretases da Proteína Precursora do Amiloide/metabolismo , Betacoronavirus/genética , Betacoronavirus/metabolismo , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Células Cultivadas , Infecções por Coronavirus/virologia , Fibronectinas/genética , Fibronectinas/metabolismo , Furina/genética , Furina/metabolismo , Ontologia Genética , Histona Acetiltransferases/genética , Histona Acetiltransferases/metabolismo , Histona Desacetilase 2/genética , Histona Desacetilase 2/metabolismo , Humanos , Histona Desmetilases com o Domínio Jumonji/genética , Histona Desmetilases com o Domínio Jumonji/metabolismo , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Modelos Biológicos , Anotação de Sequência Molecular , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Obesidade/virologia , Pandemias , Peptidil Dipeptidase A/genética , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/virologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Transdução de Sinais , Sirtuína 1/genética , Sirtuína 1/metabolismo , Receptor 3 Toll-Like/genética , Receptor 3 Toll-Like/metabolismo , Proteínas rab1 de Ligação ao GTP/genética , Proteínas rab1 de Ligação ao GTP/metabolismo
13.
Anticancer Res ; 40(6): 3155-3161, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32487610

RESUMO

BACKGROUND/AIM: The deacetylase sirtuin1 (SIRT1) inhibits tumor suppressor p53 and may promote tumorigenesis; however, SIRT1 effects on leukemia cells are controversial. The aim of this study was to clarify the activity of SIRT1 in leukemia cells. MATERIALS AND METHODS: The effects of SIRT1 inhibition or activation and SIRT1 knockdown or overexpression were examined in two T cell acute lymphoblastic leukemia (T-ALL) cell lines carrying NOTCH1 mutations and three acute myeloid leukemia (AML) cell lines. RESULTS: The growth of T-ALL cells was promoted by SIRT1 inhibition and SIRT1 knockdown but was reduced by SIRT1 activation and overexpression; however, no effects were observed in AML cells. SIRT1 activation decreased NOTCH, NF-κB, and mTOR signaling and inhibited p53, suggesting that the possible mechanisms of T-ALL growth suppression by SIRT1 are independent of p53. CONCLUSION: SIRT1 activators acting through the down-regulation of NOTCH, NF-κB, and mTOR pathways can be novel targeted drugs for NOTCH1-mutated T-ALLs.


Assuntos
NF-kappa B/metabolismo , Leucemia-Linfoma Linfoblástico de Células T Precursoras/metabolismo , Receptores Notch/metabolismo , Sirtuína 1/metabolismo , Carbazóis/farmacologia , Processos de Crescimento Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Técnicas de Silenciamento de Genes , Humanos , Mutação , Leucemia-Linfoma Linfoblástico de Células T Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células T Precursoras/patologia , Receptor Notch1/genética , Receptor Notch1/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sirtuína 1/antagonistas & inibidores , Sirtuína 1/biossíntese , Sirtuína 1/genética , Serina-Treonina Quinases TOR/metabolismo , Transfecção
14.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 36(1): 85-89, 2020 Jan 28.
Artigo em Chinês | MEDLINE | ID: mdl-32476378

RESUMO

OBJECTIVE: To observe the effects of resveratrol on body composition in adult catch-up growth rats and to explore the possible mechanism. METHODS: Eight-week-old male SD rats were randomly divided into 6 groups: normal controls for 4 weeks (NC4) group, caloric restriction for 4 weeks (R4) group, calorie restriction meanwhile resveratrol treatment for 4 weeks (R4E) group, normal controls for 12 weeks (NC12) group, catch-up growth (CUG) group and catch-up growth meanwhile resveratrol treatment for 8 weeks (CUGE) group. At the end of the four-week and twelve-week experimental period, the body weight, muscle and fat content of trunk and whole body, the ratio of trunk to whole body fat were detected, and at the end of twelve-week experimental period, the expression of SIRT1 in skeletal muscle and epididymal adipose tissue, and the expression of PPARγ in epididymal adipose tissue were detected. RESULTS: Compared with NC12 group, the fat content of trunk and whole body and trunk to whole body fat ratio in CUG group were increased significantly, along with the expression of PPARγ in epididymal adipose tissue was increased significantly (P<0.05), while the muscle content of trunk and whole body, the expression of SIRT1 in skeletal muscle and epididymal adipose tissue in CUG group were decreased significantly compared with NC12 group (P<0.05 or P<0.01); compared with CUG group, oral administration of resveratrol distinctly reduced the body fat content and trunk to whole body fat ratio in the CUGE groups, and the expression of PPARγ in epididymal adipose tissue of CUGE group was also significantly decreased (P<0.05). Meanwhile, the muscle content and the expression of SIRT1 in skeletal muscle and epididymal adipose tissue in CUGE group were significantly increased compared with the CUG group (P<0.05). CONCLUSION: Resveratrol can decrease body fat content, increase muscle content and improve abdominal fat accumulation in adult catch-up growth rats, and its mechanism may be associated with increasing SIRT1 expression in skeletal muscle and visceral adipose tissue, decreasing PPARγ expression in visceral adipose tissue.


Assuntos
Composição Corporal/efeitos dos fármacos , Resveratrol/farmacologia , Tecido Adiposo , Animais , Restrição Calórica , Gordura Intra-Abdominal , Masculino , Músculo Esquelético , PPAR gama/metabolismo , Ratos , Ratos Sprague-Dawley , Sirtuína 1/metabolismo
15.
Nat Commun ; 11(1): 2814, 2020 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-32499508

RESUMO

Food consumption is fundamental for life, and eating disorders often result in devastating or life-threatening conditions. Anorexia nervosa (AN) is characterized by a persistent restriction of energy intake, leading to lowered body weight, constant fear of gaining weight, and psychological disturbances of body perception. Herein, we demonstrate that SIRT1 inhibition, both genetically and pharmacologically, delays the onset and progression of AN behaviors in activity-based anorexia (ABA) models, while SIRT1 activation accelerates ABA phenotypes. Mechanistically, we suggest that SIRT1 promotes progression of ABA, in part through its interaction with NRF1, leading to suppression of a NMDA receptor subunit Grin2A. Our results suggest that AN may arise from pathological positive feedback loops: voluntary food restriction activates SIRT1, promoting anxiety, hyperactivity, and addiction to starvation, exacerbating the dieting and exercising, thus further activating SIRT1. We propose SIRT1 inhibition can break this cycle and provide a potential therapy for individuals suffering from AN.


Assuntos
Anorexia Nervosa/metabolismo , Regulação da Expressão Gênica , Fator 1 Nuclear Respiratório/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Sirtuína 1/metabolismo , Animais , Peso Corporal , Carbazóis/farmacologia , Modelos Animais de Doenças , Feminino , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas do Tecido Nervoso/metabolismo , Fenótipo , Resveratrol/farmacologia , Estresse Mecânico , Regulação para Cima
16.
Nucleic Acids Res ; 48(12): 6530-6546, 2020 07 09.
Artigo em Inglês | MEDLINE | ID: mdl-32432680

RESUMO

OGG1 initiated base excision repair (BER) is the major pathway for repair of oxidative DNA base damage 8-oxoguanine (8-oxoG). Here, we report that RECQL4 DNA helicase, deficient in the cancer-prone and premature aging Rothmund-Thomson syndrome, physically and functionally interacts with OGG1. RECQL4 promotes catalytic activity of OGG1 and RECQL4 deficiency results in defective 8-oxoG repair and increased genomic 8-oxoG. Furthermore, we show that acute oxidative stress leads to increased RECQL4 acetylation and its interaction with OGG1. The NAD+-dependent protein SIRT1 deacetylates RECQL4 in vitro and in cells thereby controlling the interaction between OGG1 and RECQL4 after DNA repair and maintaining RECQL4 in a low acetylated state. Collectively, we find that RECQL4 is involved in 8-oxoG repair through interaction with OGG1, and that SIRT1 indirectly modulates BER of 8-oxoG by controlling RECQL4-OGG1 interaction.


Assuntos
DNA Glicosilases/metabolismo , Reparo do DNA , RecQ Helicases/metabolismo , Sirtuína 1/metabolismo , Acetilação , Linhagem Celular Tumoral , Guanosina/análogos & derivados , Guanosina/genética , Células HEK293 , Humanos , Estresse Oxidativo , Ligação Proteica
17.
Ann Rheum Dis ; 79(7): 891-900, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32381568

RESUMO

OBJECTIVES: To decipher the phenotype of endothelial cells (ECs) derived from circulating progenitors issued from patients with rheumatoid arthritis (RA). METHODS: RA and control ECs were compared according to their proliferative capacities, apoptotic profile, response to tumour necrosis factor (TNF)-α stimulation and angiogenic properties. Microarray experiments were performed to identify gene candidates relevant to pathological angiogenesis. Identified candidates were detected by RT-PCR and western blot analysis in ECs and by immunohistochemistry in the synovium. Their functional relevance was then evaluated in vitro after gene invalidation by small interfering RNA and adenoviral gene overexpression, and in vivo in the mouse model of methyl-bovine serum albumin-(mBSA)-induced arthritis. RESULTS: RA ECs displayed higher proliferation rate, greater sensitisation to TNF-α and enhanced in vitro and in vivo angiogenic capacities. Microarray analyses identified the NAD-dependent protein deacetylase sirtuin-1 (SIRT1) as a relevant gene candidate. Decreased SIRT1 expression was detected in RA ECs and synovial vessels. Deficient endothelial SIRT1 expression promoted a proliferative, proapoptotic and activated state of ECs through the acetylation of p53 and p65, and lead the development of proangiogenic capacities through the upregulation of the matricellular protein cysteine-rich angiogenic protein-61. Conditional deletion of SIRT1 in ECs delayed the resolution of experimental methyl-bovine serum albumin-(mBSA)-induced arthritis. Conversely, SIRT1 activation reversed the pathological phenotype of RA ECs and alleviates signs of experimental mBSA-induced arthritis. CONCLUSIONS: These results support a role of SIRT1 in RA and may have therapeutic implications, since targeting angiogenesis, and especially SIRT1, might be used as a complementary therapeutic approach in RA.


Assuntos
Artrite Reumatoide/genética , Neovascularização Patológica/genética , Sirtuína 1/metabolismo , Membrana Sinovial/irrigação sanguínea , Adulto , Animais , Apoptose/genética , Artrite Experimental , Artrite Reumatoide/patologia , Proliferação de Células/genética , Células Endoteliais/metabolismo , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Neovascularização Patológica/patologia , Transdução de Sinais/genética , Fator de Necrose Tumoral alfa/metabolismo , Regulação para Cima/genética
18.
Cell Prolif ; 53(6): e12818, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32468629

RESUMO

OBJECTIVES: Myocardial ischaemia/reperfusion (MI/R) injury is associated with adverse cardiovascular outcomes after acute myocardial infarction. However, the molecular mechanisms underlying MI/R injury are unclear. This study investigated the role of long non-coding RNA (lncRNA) Oip5-as1 in regulating mitochondria-mediated apoptosis during MI/R injury. MATERIALS AND METHODS: Sprague-Dawley rats were subjected to MI/R induced by ligation of the left anterior descending coronary artery followed by reperfusion. H9c2 cells were incubated under oxygen-glucose deprivation/reoxygenation (OGD/R) conditions to mimic in vivo MI/R. RT-qPCR and Western blot were used to evaluate gene and protein levels. CCK-8 assay, biochemical assay and flow cytometric analysis were performed to assess the function of Oip5-as1. The dual-luciferase gene reporter assay and RIP assay were conducted as needed. RESULTS: Oip5-as1 expression was downregulated in the hearts of rats with MI/R and in H9c2 cells treated with OGD/R. Oip5-as1 overexpression alleviated reactive oxygen species-driven mitochondrial injury and consequently decreased apoptosis in MI/R rats and H9c2 cells exposed to OGD/R. Mechanistically, Oip5-as1 acted as a competing endogenous RNA of miR-29a and thus decreased its expression. Inhibition of miR-29a reduced the oxidative stress and cytotoxicity induced by OGD/R. Overexpression of miR-29a reversed the anti-apoptotic effect of Oip5-as1 in H9c2 cells treated with OGD/R. Further experiments identified SIRT1 as a downstream target of miR-29a. Oip5-as1 upregulated SIRT1 expression and activated the AMPK/PGC1α pathway by targeting miR-29a, thus reducing the apoptosis triggered by OGD/R. However, these effects were reversed by a selective SIRT1 inhibitor, EX527. CONCLUSIONS: Oip5-as1 suppresses miR-29a leading to activation of the SIRT1/AMPK/PGC1α pathway, which attenuates mitochondria-mediated apoptosis during MI/R injury. Our findings thus provide new insights into the molecular mechanisms of MI/R injury.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , MicroRNAs/metabolismo , Traumatismo por Reperfusão Miocárdica/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , RNA Longo não Codificante/metabolismo , Sirtuína 1/metabolismo , Animais , Apoptose , Linhagem Celular , Células Cultivadas , Potencial da Membrana Mitocondrial , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Estresse Oxidativo , RNA Longo não Codificante/fisiologia , Ratos Sprague-Dawley , Transdução de Sinais
19.
J Biomed Sci ; 27(1): 61, 2020 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-32381096

RESUMO

BACKGROUND: The disruption of the blood-brain barrier (BBB) plays a critical event in the pathogenesis of ischemia stroke. TGR5 is recognized as a potential target for the treatment for neurologic disorders. METHODS: This study investigated the roles of TGR5 activation in attenuating BBB damage and underlying mechanisms after middle cerebral artery occlusion (MCAO). Sprague-Dawley rats were subjected to model of MCAO and TGR5 agonist, INT777, was administered intranasally. Small interfering RNA (siRNA) for TGR5 and BRCA1 were administered through intracerebroventricular injection 48 h before MCAO. Infarct volumes, brain water content, BBB permeability, neurological scores, Western blot, immunofluorescence staining and co- immunoprecipitation were evaluated. RESULTS: Endogenous TGR5 and BRCA1 were upregulated in the injured hemisphere after MCAO and TGR5 expressed in endothelial cells. Treatment with INT777 alleviated brain water content and BBB permeability, reduced infarction volume and improved neurological scores at 24 h and 72 h after ischemia. INT777 administration increased BRCA1 and Sirt1 expression, as well as upregulated expressions of tight junction proteins. Ischemic damage induced interaction of TGR5 with BRCA1. TGR5 siRNA and BRCA1 siRNA significantly inhibited expressions of BRCA1 and Sirt1, aggravated BBB permeability and exacerbated stroke outcomes after MCAO. The protective effects of INT777 at 24 h after MCAO were also abolished by TGR5 siRNA or BRCA1 siRNA. CONCLUSIONS: Our findings demonstrate that activating TGR5 could reduce BBB breakdown and improve neurological functions through BRCA1/Sirt1 signaling pathway after MCAO. TGR5 may serve as a potential new candidate to relieve brain injury after MCAO.


Assuntos
Barreira Hematoencefálica/fisiologia , Infarto da Artéria Cerebral Média/patologia , Receptores Acoplados a Proteínas-G/genética , Transdução de Sinais/genética , Animais , Proteína BRCA1/genética , Proteína BRCA1/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores Acoplados a Proteínas-G/metabolismo , Sirtuína 1/genética , Sirtuína 1/metabolismo
20.
Mol Cell ; 78(5): 835-849.e7, 2020 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-32369735

RESUMO

Disrupted sleep-wake and molecular circadian rhythms are a feature of aging associated with metabolic disease and reduced levels of NAD+, yet whether changes in nucleotide metabolism control circadian behavioral and genomic rhythms remains unknown. Here, we reveal that supplementation with the NAD+ precursor nicotinamide riboside (NR) markedly reprograms metabolic and stress-response pathways that decline with aging through inhibition of the clock repressor PER2. NR enhances BMAL1 chromatin binding genome-wide through PER2K680 deacetylation, which in turn primes PER2 phosphorylation within a domain that controls nuclear transport and stability and that is mutated in human advanced sleep phase syndrome. In old mice, dampened BMAL1 chromatin binding, transcriptional oscillations, mitochondrial respiration rhythms, and late evening activity are restored by NAD+ repletion to youthful levels with NR. These results reveal effects of NAD+ on metabolism and the circadian system with aging through the spatiotemporal control of the molecular clock.


Assuntos
Relógios Circadianos/fisiologia , Ritmo Circadiano/genética , Proteínas Circadianas Period/metabolismo , Fatores de Transcrição ARNTL/genética , Fatores Etários , Envelhecimento/genética , Animais , Proteínas CLOCK/genética , Ritmo Circadiano/fisiologia , Citocinas/metabolismo , Feminino , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , NAD/metabolismo , Proteínas Circadianas Period/genética , Sirtuína 1/metabolismo , Sirtuínas/metabolismo
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