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1.
Entropy (Basel) ; 26(6)2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38920481

RESUMO

Recently, a concept known as µTRISTAN, which involves the acceleration of µ+, has been proposed. This initiative has led to considerations of a new design for a neutrino factory. Additionally, leveraging the polarization of µ+, measurements of T violation in neutrino oscillations are also being explored. In this paper, we present analytical expressions for T violation in neutrino oscillations within the framework of standard three-flavor neutrino oscillations, a scenario involving nonstandard interactions, and a case of unitarity violation. We point out that examining the energy spectrum of T violation may be useful for probing new physics effects.

2.
Circulation ; 132(12): 1081-93, 2015 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-26202810

RESUMO

BACKGROUND: Sirt7, 1 of the 7 members of the mammalian sirtuin family, promotes oncogenic transformation. Tumor growth and metastasis require fibrotic and angiogenic responses. Here, we investigated the role of Sirt7 in cardiovascular tissue repair process. METHODS AND RESULTS: In wild-type mice, Sirt7 expression increased in response to acute cardiovascular injury, including myocardial infarction and hind-limb ischemia, particularly at the active wound healing site. Compared with wild-type mice, homozygous Sirt7-deficient (Sirt7(-/-)) mice showed susceptibility to cardiac rupture after myocardial infarction, delayed blood flow recovery after hind-limb ischemia, and impaired wound healing after skin injury. Histological analysis showed reduced fibrosis, fibroblast differentiation, and inflammatory cell infiltration in the border zone of infarction in Sirt7(-/-) mice. In vitro, Sirt7(-/-) mouse-derived or Sirt7 siRNA-treated cardiac fibroblasts showed reduced transforming growth factor-ß signal activation and low expression levels of fibrosis-related genes compared with wild-type mice-derived or control siRNA-treated cells. These changes were accompanied by reduction in transforming growth factor receptor I protein. Loss of Sirt7 activated autophagy in cardiac fibroblasts. Transforming growth factor-ß receptor I downregulation induced by loss of Sirt7 was blocked by autophagy inhibitor, and interaction of Sirt7 with protein interacting with protein kinase-Cα was involved in this process. CONCLUSION: Sirt7 maintains transforming growth factor receptor I by modulating autophagy and is involved in the tissue repair process.


Assuntos
Fibroblastos/efeitos dos fármacos , Coração/fisiologia , Neovascularização Fisiológica/fisiologia , Regeneração/fisiologia , Transdução de Sinais/fisiologia , Sirtuínas/fisiologia , Fator de Crescimento Transformador beta/fisiologia , Animais , Autofagia/efeitos dos fármacos , Modelos Animais de Doenças , Fibroblastos/patologia , Membro Posterior/irrigação sanguínea , Técnicas In Vitro , Isquemia/fisiopatologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Infarto do Miocárdio/fisiopatologia , RNA Interferente Pequeno/farmacologia , Sirtuínas/deficiência , Sirtuínas/genética , Cicatrização/fisiologia
3.
Arterioscler Thromb Vasc Biol ; 34(3): 616-25, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24371084

RESUMO

OBJECTIVE: There are currently no specific strategies for the treatment or prevention of vascular dementia. White matter lesions, a common pathology in cerebral small vessel disease, are a major cause of vascular dementia. We investigated whether apoptosis signal-regulating kinase 1 (ASK1) might be a key molecule in cerebral hypoperfusion, associated with blood-brain barrier breakdown and white matter lesions. APPROACH AND RESULTS: A mouse model of cognitive impairment was developed by inducing chronic cerebral hypoperfusion in white matter including the corpus callosum via bilateral common carotid artery stenosis (BCAS) surgery. BCAS-induced white matter lesions caused cognitive decline in C57BL/6J (wild-type) mice but not in ASK1-deficient (ASK1(-/-)) mice. Phosphorylated ASK1 increased in wild-type mouse brains, and phosphorylated p38 and tumor necrosis factor-α expression increased in corpus callosum cerebral endothelial cells after BCAS in wild-type mice but not in ASK1(-/-) mice. BCAS decreased claudin-5 expression and disrupted blood-brain barrier in the corpus callosum of wild-type but not ASK1(-/-) mice. Cerebral nitrotyrosine was increased in wild-type and ASK1(-/-) BCAS mice. Cerebral phosphorylated ASK1 did not increase in wild-type mice treated with NADPH-oxidase inhibitor. A p38 inhibitor and NADPH-oxidase inhibitor mimicked the protective effect of ASK1 deficiency against cognitive impairment. Specific ASK1 inhibitor prevented cognitive decline in BCAS mice. In vitro oxygen-glucose deprivation and tumor necrosis factor-α stimulation caused the disruption of endothelial tight junctions from wild-type mice but not ASK1(-/-) mice. CONCLUSIONS: Oxidative stress-ASK1-p38 cascade plays a role in the pathogenesis of cognitive impairment, through blood-brain barrier breakdown via the disruption of endothelial tight junctions. ASK1 might be a promising therapeutic target for chronic cerebral hypoperfusion-induced cognitive impairment.


Assuntos
Estenose das Carótidas/complicações , Demência Vascular/etiologia , MAP Quinase Quinase Quinase 5/fisiologia , Animais , Barreira Hematoencefálica , Isquemia Encefálica/etiologia , Isquemia Encefálica/fisiopatologia , Isquemia Encefálica/prevenção & controle , Isquemia Encefálica/psicologia , Estenose das Carótidas/fisiopatologia , Estenose das Carótidas/psicologia , Circulação Cerebrovascular/efeitos dos fármacos , Condicionamento Operante/fisiologia , Corpo Caloso/irrigação sanguínea , Demência Vascular/enzimologia , Demência Vascular/fisiopatologia , Demência Vascular/prevenção & controle , Células Endoteliais/enzimologia , Comportamento Exploratório , MAP Quinase Quinase Quinase 5/antagonistas & inibidores , MAP Quinase Quinase Quinase 5/deficiência , MAP Quinase Quinase Quinase 5/genética , Masculino , Aprendizagem em Labirinto/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Modelos Animais , Neuroglia/fisiologia , Estresse Oxidativo , Fosforilação , Inibidores de Proteínas Quinases/farmacologia , Processamento de Proteína Pós-Traducional , Reconhecimento Psicológico , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Junções Íntimas , Fator de Necrose Tumoral alfa/farmacologia
4.
Heliyon ; 9(9): e20079, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37809500

RESUMO

Aim: Inspiratory muscle training (IMT) improves respiratory muscle function and exercise tolerance in patients with chronic obstructive pulmonary disease (COPD), but the detailed mechanism is unclear. The purpose of this study is to elucidate the mechanism of functional improvement by IMT from P0.1, an index of respiratory central output, and thickness of diaphragm (Tdi), a noninvasive and reliable ultrasound examination. Methods: This clinical trial study enrolled 13 elderly patients with COPD. IMT was performed using the POWER breathe® Medic Plus breathing trainer in combination with each participant's outpatient rehabilitation regimen. Starting at 20% of the maximal inspiratory pressure (PImax) and increasing to 50%, the participants performed 30 IMT repetitions twice a day for 2 months. P0.1 is the value of airway-occlusion pressure at 0.1 s after the start of inspiratory flow, and Tdi was measured at rest and maximal breathing. Results: PImax and 6-min walking distance(6MWD) significantly increased after training. Tdi at resting inspiration and expiration, and maximal inspiration also significantly increased after training. In addition, the Borg Scale scores for dyspnea and leg fatigue and the respiratory rate of the 1-min recovery period after the 6MWD significantly decreased. There was no significant difference in P0.1. Conclusions: These results suggest that the effects of IMT may be attributed to the improved peripheral factors rather than to the central factors in elderly COPD patients.

5.
Front Neurosci ; 17: 1149603, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37456993

RESUMO

Adult neural stem cells (NSCs) in the mouse subventricular zone (SVZ) serve as a lifelong reservoir for newborn olfactory bulb neurons. Recent studies have identified a slowly dividing subpopulation of embryonic neural stem-progenitor cells (NPCs) as the embryonic origin of adult NSCs. Yet, little is known about how these slowly dividing embryonic NPCs are maintained until adulthood while other NPCs are extinguished by the completion of brain development. The extracellular matrix (ECM) is an essential component of stem cell niches and thus a key determinant of stem cell fate. Here we investigated tissue inhibitors of metalloproteinases (TIMPs)-regulators of ECM remodeling-for their potential roles in the establishment of adult NSCs. We found that Timp2, Timp3, and Timp4 were expressed at high levels in slowly dividing NPCs compared to rapidly dividing NPCs. Deletion of TIMP3 reduced the number of adult NSCs and neuroblasts in the lateral SVZ. In addition, overexpression of TIMP3 in the embryonic NPCs suppressed neuronal differentiation and upregulated the expression levels of Notch signaling relating genes. These results thus suggest that TIMP3 keeps the undifferentiated state of embryonic NPCs, leading to the establishment and maintenance of adult NSCs.

6.
Chem Commun (Camb) ; 59(66): 9956-9959, 2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37526022

RESUMO

Bis(dithienylethene)-based BINOL-derived phosphoric acid (DTE-BPA) has been developed as a light-controlled chiral organocatalyst for the first time. The photoinduced modulation of the reactivity and selectivity via the open/close isomerization of the DTE scaffold led to superior light-controlled ability in the enantioselective aza-Friedel-Crafts reaction of aldimines with indoles. DFT studies showed that photoisomerization is accompanied by a shift of 1.1 pKa units between the open and closed isomers.

7.
Biochem Biophys Res Commun ; 419(4): 612-6, 2012 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-22382030

RESUMO

ANRIL is a newly discovered non-coding RNA lying on the strongest genetic susceptibility locus for cardiovascular disease (CVD) in the chromosome 9p21 region. Genome-wide association studies have been linking polymorphisms in this locus with CVD and several other major diseases such as diabetes and cancer. The role of this non-coding RNA in atherosclerosis progression is still poorly understood. In this study, we investigated the implication of ANRIL in the modulation of gene sets directly involved in atherosclerosis. We designed and tested siRNA sequences to selectively target two exons (exon 1 and exon 19) of the transcript and successfully knocked down expression of ANRIL in human aortic vascular smooth muscle cells (HuAoVSMC). We used a pathway-focused RT-PCR array to profile gene expression changes caused by ANRIL knock down. Notably, the genes affected by each of the siRNAs were different, suggesting that different splicing variants of ANRIL might have distinct roles in cell physiology. Our results suggest that ANRIL splicing variants play a role in coordinating tissue remodeling, by modulating the expression of genes involved in cell proliferation, apoptosis, extra-cellular matrix remodeling and inflammatory response to finally impact in the risk of cardiovascular disease and other pathologies.


Assuntos
Aterosclerose/genética , Doenças Cardiovasculares/genética , Regulação da Expressão Gênica , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo , RNA não Traduzido/metabolismo , Linhagem Celular , Proliferação de Células , Técnicas de Silenciamento de Genes , Humanos , Splicing de RNA , RNA Longo não Codificante , RNA não Traduzido/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
8.
Cerebrovasc Dis ; 34(5-6): 385-92, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23207319

RESUMO

BACKGROUND: Periodontitis increases the risk of atherosclerotic cardiovascular disease and ischemic stroke. In this study, we evaluated whether serum antibody levels against individual periodontal pathogens are significantly associated with ischemic stroke subtypes and their risk factors. METHODS: Patients with acute ischemic stroke (n = 132; 74 male and 58 female, 71.3 ± 10.7 years) and patients with no previous stroke (n = 77; 38 male and 39 female, 70.7 ± 9.5 years) were consecutively enrolled in this study. Stroke subtype was evaluated based on the Trial of Org 10172 in Acute Stroke Treatment classification. Serum was obtained from each patient after obtaining their consent to participate in the study. The levels of serum antibodies against Aggregatibacter actinomycetemcomitans (Aa), Porphyromonas gingivalis (Pg) and Prevotella intermedia (Pi) were evaluated by ELISA. Serum high-sensitivity C-reactive protein (hs-CRP) levels were measured by nephelometry. RESULTS: Serum hs-CRP levels were significantly associated with acute ischemic stroke even after controlling for acute ischemic stroke, hypertension, diabetes mellitus and bulb/ internal carotid artery (ICA) atherosclerosis which were statistically selected (coefficient 0.245, 95% CI 0.142-0.347, p < 0.0001). The serum-antibody level of Pi was significantly higher in atherothrombotic-stroke patients than in patients with no previous stroke (p = 0.0035). Detectable serum anti-Pg antibody was significantly associated with atrial fibrillation (overall χ(2) = 35.5, R(2) = 0.18, n = 209, p < 0.0001; anti-Pg antibody: OR 4.36, 95% CI 1.71-12.10, p = 0.0017), and detectable serum anti-Pi antibody was significantly associated with bulb/ICA atherosclerosis after controlling for the statistically selected associated factors (overall χ(2) = 46.1, R(2) = 0.18, n = 209, p < 0.0001; anti-Pg antibody: OR 16.58, 95% CI 3.96-78.93, p < 0.0001). The levels of serum anti-Pi antibody were significantly associated with atherothrombotic stroke with the statistically selected associated factors excluding bulb/ICA atherosclerosis (overall χ(2) = 77.0, R(2) = 0.44, n = 129, p < 0.0001; anti-Pi antibody: OR 23.6, 95% CI 2.65-298.2, p = 0.008). However, when we included bulb/ICA atherosclerosis in this model, the levels of serum anti-Pi antibody were no longer significantly associated with atherothrombotic stroke (overall χ(2) = 98.0, R(2) = 0.56, n = 129, p < 0.0001; anti-Pi antibody: p = 0.107). CONCLUSIONS: Our results suggest that anti-Pg antibody is associated with atrial fibrillation and that anti-Pi antibody is associated with carotid artery atherosclerosis. In addition, anti-Pi antibody may be associated with atherothrombotic stroke through its association with carotid artery atherosclerosis. Thus, periodontitis may lead to serious systemic diseases.


Assuntos
Anticorpos Antibacterianos/sangue , Infecções por Bacteroidaceae/complicações , Isquemia Encefálica/etiologia , Periodontite/complicações , Porphyromonas gingivalis/imunologia , Prevotella intermedia/imunologia , Idoso , Idoso de 80 Anos ou mais , Aterosclerose/etiologia , Infecções por Bacteroidaceae/sangue , Infecções por Bacteroidaceae/imunologia , Isquemia Encefálica/sangue , Isquemia Encefálica/imunologia , Proteína C-Reativa/metabolismo , Artérias Carótidas/metabolismo , Doenças das Artérias Carótidas/sangue , Doenças das Artérias Carótidas/etiologia , Doenças das Artérias Carótidas/imunologia , Feminino , Humanos , Hipertensão/etiologia , Masculino , Pessoa de Meia-Idade , Periodontite/imunologia , Porphyromonas gingivalis/metabolismo , Prevotella intermedia/metabolismo , Fatores de Risco
9.
Arterioscler Thromb Vasc Biol ; 31(12): 2872-80, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21940947

RESUMO

OBJECTIVE: Whole-body periodic acceleration (WBPA) has been developed as a passive exercise technique to improve endothelial function by increasing shear stress through repetitive movements in spinal axis direction. We investigated the effects of WBPA on blood flow recovery in a mouse model of hindlimb ischemia and in patients with peripheral arterial disease. METHODS AND RESULTS: After unilateral femoral artery excision, mice were assigned to either the WBPA (n=15) or the control (n=13) group. WBPA was applied at 150 cpm for 45 minutes under anesthesia once a day. WBPA significantly increased blood flow recovery after ischemic surgery, as determined by laser Doppler perfusion imaging. Sections of ischemic adductor muscle stained with anti-CD31 antibody showed a significant increase in capillary density in WBPA mice compared with control mice. WBPA increased the phosphorylation of endothelial nitric oxide synthase (eNOS) in skeletal muscle. The proangiogenic effect of WBPA on ischemic limb was blunted in eNOS-deficient mice, suggesting that the stimulatory effects of WBPA on revascularization are eNOS dependent. Quantitative real-time polymerase chain reaction analysis showed significant increases in angiogenic growth factor expression in ischemic hindlimb by WBPA. Facilitated blood flow recovery was observed in a mouse model of diabetes despite there being no changes in glucose tolerance and insulin sensitivity. Furthermore, both a single session and 7-day repeated sessions of WBPA significantly improved blood flow in the lower extremity of patients with peripheral arterial disease. CONCLUSIONS: WBPA increased blood supply to ischemic lower extremities through activation of eNOS signaling and upregulation of proangiogenic growth factor in ischemic skeletal muscle. WBPA is a potentially suitable noninvasive intervention to facilitate therapeutic angiogenesis.


Assuntos
Aceleração , Membro Posterior/irrigação sanguínea , Isquemia/terapia , Terapia Passiva Contínua de Movimento/métodos , Neovascularização Fisiológica/fisiologia , Doença Arterial Periférica/terapia , Condicionamento Físico Animal/métodos , Idoso , Animais , Modelos Animais de Doenças , Endotélio Vascular/fisiopatologia , Feminino , Fator 2 de Crescimento de Fibroblastos/metabolismo , Seguimentos , Membro Posterior/metabolismo , Humanos , Isquemia/fisiopatologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Músculo Esquelético/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Doença Arterial Periférica/fisiopatologia , Proteínas Proto-Oncogênicas c-sis/metabolismo , Fluxo Sanguíneo Regional/fisiologia , Resultado do Tratamento , Fator A de Crescimento do Endotélio Vascular/metabolismo
11.
Biochem Biophys Res Commun ; 410(3): 508-13, 2011 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-21679694

RESUMO

Experimental and clinical data support the notion that peroxisome proliferator-activated receptor γ (PPARγ) activation is associated with anti-atherosclerosis as well as anti-diabetic effect. Telmisartan, an angiotensin receptor blocker (ARB), acts as a partial PPARγ agonist. We hypothesized that telmisartan protects against diabetic vascular complications, through PPARγ activation. We compared the effects of telmisartan, telmisartan combined with GW9662 (a PPARγ antagonist), and losartan with no PPARγ activity on vascular injury in obese type 2 diabetic db/db mice. Compared to losartan, telmisartan significantly ameliorated vascular endothelial dysfunction, downregulation of phospho-eNOS, and coronary arterial remodeling in db/db mice. More vascular protective effects of telmisartan than losartan were associated with greater anti-inflammatory effects of telmisartan, as shown by attenuation of vascular nuclear factor kappa B (NFκB) activation and tumor necrosis factor α. Coadministration of GW9662 with telmisartan abolished the above mentioned greater protective effects of telmisartan against vascular injury than losartan in db/db mice. Thus, PPARγ activity appears to be involved in the vascular protective effects of telmisartan in db/db mice. Moreover, telmisartan, but not losartan, prevented the downregulation of vascular PPARγ in db/db mice and this effect of telmisartan was cancelled by the coadministration of GW9662. Our data provided the first evidence indicating that PPARγ activity of telmisartan contributed to the protective effects of telmisartan against diabetic vascular complication. PPARγ activity of telmisartan was involved in the normalization of vascular PPARγ downregulation in diabetic mice. Thus, telmisartan seems to exert vascular protective effects in hypertensive patients with diabetes.


Assuntos
Bloqueadores do Receptor Tipo 1 de Angiotensina II/uso terapêutico , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Benzimidazóis/uso terapêutico , Benzoatos/uso terapêutico , Diabetes Mellitus Tipo 2/complicações , Angiopatias Diabéticas/prevenção & controle , Obesidade/complicações , PPAR gama/metabolismo , Anilidas/administração & dosagem , Animais , Angiopatias Diabéticas/etiologia , Modelos Animais de Doenças , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Telmisartan
12.
J Hepatol ; 52(6): 903-12, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20392512

RESUMO

BACKGROUND & AIMS: Nonalcoholic fatty liver disease (NAFLD) is currently recognized as a global health issue and encompasses a wide spectrum of entities, ranging from simple hepatic steatosis to nonalcoholic steatohepatitis (NASH). The lack of a spontaneous animal model of NASH, however, has hampered basic research in this field. METHODS: We examined the hepatic lesions in the inbred Fatty Liver Shionogi (FLS) mouse, which exhibits type 2 diabetes, and investigated the molecular mechanism leading to NAFLD/NASH. Using vector-mediated hepatic expression of microsomal triglyceride transfer protein (MTP), a key molecule for very low density lipoprotein (VLDL) assembly and export, its contribution to the hepatic lesions as well as to glucose intolerance was examined. RESULTS: The FLS mouse, maintained on normal chow, exhibited excessive hepatic triglyceride (TG) accumulation due to impaired VLDL secretion, and subsequently hepatic lesions comparable to NASH, with increased expression of inflammatory molecules as well as insulin resistance. Gene expression and Western blot analyses demonstrated reduced hepatic expression of MTP in the FLS mouse. Hepatic induction of MTP resulted in a reduction in hepatic TG accumulation, improvement of VLDL export, and amelioration of NASH-like lesions, as well as glucose intolerance. CONCLUSIONS: These data suggest that the FLS mouse could serve as a spontaneous model of NASH with insulin resistance, and that reduced MTP is involved in the development of NASH, pointing towards MTP as a critical target for the prevention and treatment of NASH.


Assuntos
Proteínas de Transporte/metabolismo , Modelos Animais de Doenças , Fígado Gorduroso/metabolismo , Camundongos Mutantes , Microssomos Hepáticos/metabolismo , Animais , Glicemia/metabolismo , Proteínas de Transporte/genética , VLDL-Colesterol/sangue , Fígado Gorduroso/patologia , Fígado Gorduroso/fisiopatologia , Expressão Gênica/fisiologia , Intolerância à Glucose/metabolismo , Intolerância à Glucose/patologia , Intolerância à Glucose/fisiopatologia , Insulina/sangue , Resistência à Insulina/fisiologia , Metabolismo dos Lipídeos/genética , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Cirrose Hepática/fisiopatologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microssomos Hepáticos/patologia , Fenótipo , Transfecção , Triglicerídeos/metabolismo
13.
Biochem Biophys Res Commun ; 403(3-4): 258-63, 2010 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-21059340

RESUMO

The effect of calcium channel blockers (CCBs) on type 2 diabetes is still unclear. The present study was undertaken to examine the efficacy of nifedipine, a dihydropyridine CCB, on obesity, glucose intolerance and vascular endothelial dysfunction in db/db mice (a mouse model of obesity and type 2 diabetes). db/db mice, fed high-fat diet (HFD) were treated with vehicle, nifedipine (10 mg kg(-1) day(-1)) or hydralazine (5 mg kg(-1) day(-1)) for 4 weeks, and the protective effects were compared. Although nifedipine and hydralazine exerted similar blood pressure lowering in db/db mice, neither affected body weight, fat weight, and glucose intolerance of db/db mice. However, nifedipine, but not hydralazine, significantly improved vascular endothelial function in db/db mice, being accompanied by more attenuation of vascular superoxide by nifedipine than hydralazine. These protective effects of nifedipine were attributed to the attenuation of eNOS uncoupling as shown by the prevention of vascular endothelial nitric oxide synthase (eNOS) dimer disruption, and the prevention of dihydrofolate reductase (DHFR) downregulation, the key enzyme responsible for eNOS uncoupling. Moreover, nifedipine, but not hydralazine, significantly prevented the decreases in phosphorylation of vascular akt and eNOS in db/db mice. Our work provided the first evidence that nifedipine prevents vascular endothelial dysfunction, through the inhibition of eNOS uncoupling and the enhancement of eNOS phosphorylation, independently of blood pressure-lowering effect. We propose that nifedipine may be a promising therapeutic agent for cardiovascular complications in type 2 diabetes.


Assuntos
Bloqueadores dos Canais de Cálcio/farmacologia , Diabetes Mellitus Experimental/enzimologia , Diabetes Mellitus Tipo 2/enzimologia , Endotélio Vascular/efeitos dos fármacos , Nifedipino/farmacologia , Óxido Nítrico Sintase Tipo III/metabolismo , Obesidade/enzimologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Modelos Animais de Doenças , Endotélio Vascular/enzimologia , Endotélio Vascular/fisiopatologia , Teste de Tolerância a Glucose , Camundongos , Camundongos Endogâmicos , Tamanho do Órgão/efeitos dos fármacos , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Superóxidos/metabolismo
14.
J Pharmacol Exp Ther ; 335(1): 70-5, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20651026

RESUMO

Type 2 diabetes plays a major role in the development of cardiovascular diseases. The present study was undertaken to investigate the effect of ezetimibe, a potent cholesterol absorption inhibitor, on cardiovascular injury of obese and type 2 diabetic db/db mice. Diabetic db/db mice fed a Western diet were given ezetimibe for 9 weeks, and the effects on cardiovascular injury and hepatic steatosis were examined. Ezetimibe treatment of db/db mice significantly improved vascular endothelial function, which was associated with the restoration of the decreased phospho-Akt and phospho-endothelial nitric-oxide synthase (eNOS). Moreover, ezetimibe also reduced vascular superoxide levels in db/db mice, accompanied by the attenuation of NADPH oxidase subunit gp91(phox) and Nox4 and the prevention of down-regulation of Cu/Zn-superoxide dismutase (SOD) and extracellular SOD. Thus, the improvement of vascular endothelial function by ezetimibe in diabetic mice seems to be attributed to the improvement of eNOS function and the attenuation of oxidative stress. Ezetimibe treatment also significantly attenuated cardiac interstitial fibrosis and coronary arterial thickening of diabetic mice and ameliorated cardiac macrophage infiltration. This improvement of cardiac injury was also related to the attenuation of NADPH oxidase-mediated oxidative stress. Furthermore, ezetimibe significantly prevented hepatic steatosis, inflammation, and oxidative stress in diabetic mice. Our work provides the first evidence that ezetimibe prevented cardiovascular injury and hepatic steatosis in diabetic mice. These beneficial effects were attributed to the attenuation of oxidative stress and inflammation and the improvement of eNOS function. Therefore, we propose that ezetimibe may be a promising therapeutic drug for obese and type 2 diabetes.


Assuntos
Anticolesterolemiantes/farmacologia , Azetidinas/farmacologia , Doenças Cardiovasculares/tratamento farmacológico , Doenças Cardiovasculares/etiologia , Diabetes Mellitus Tipo 2/complicações , Angiopatias Diabéticas/tratamento farmacológico , Fígado Gorduroso/tratamento farmacológico , Obesidade/complicações , Animais , Pressão Sanguínea/fisiologia , Vasos Sanguíneos/efeitos dos fármacos , Vasos Sanguíneos/fisiologia , Composição Corporal , Peso Corporal , Doenças Cardiovasculares/patologia , Colesterol/metabolismo , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/patologia , Angiopatias Diabéticas/patologia , Ezetimiba , Fígado Gorduroso/etiologia , Fígado Gorduroso/patologia , Teste de Tolerância a Glucose , Imuno-Histoquímica , Técnicas In Vitro , Resistência à Insulina , Fígado/química , Fígado/enzimologia , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Miocárdio/enzimologia , NADPH Oxidases/metabolismo , Superóxidos/metabolismo , Triglicerídeos/metabolismo
15.
Sci Rep ; 10(1): 17040, 2020 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-33046765

RESUMO

To test our hypothesis that the magnitude of reduction in hsCRP achieved by antihypertensive medications may predict the benefit for cardiovascular outcomes in hypertensive individuals, we performed subanalysis of the ATTEMPT-CVD study. The hypertensive participants enrolled in the ATTMEPT-CVD study were categorized into two groups according to whether achieved reduction in hsCRP levels at 6 months after initiation of antihypertensive medications from baseline was equal to or greater than 40% (responder group) or less than 40% (non-responder group). Baseline characteristics and blood pressure during follow-up period were similar between the groups. For women, the incidence of cardiovascular events was significantly less in responder group than non-responder group (P < 0.0221). However, for men, there was no significant difference between the groups regarding incident cardiovascular events (P = 0.2434). There was a significant interaction (P = 0.0187) between sexes for incident cardiovascular events. Our results provide the evidence suggesting that substantial reduction (40% or greater reduction) in hsCRP on antihypertensive medication predicts the benefit for cardiovascular outcomes in hypertensive women but it does not in hypertensive men. The magnitude of achieved reduction in hsCRP by antihypertensive medications seems to be a useful indicator of successful treatment in Japanese hypertensive women.This trial was registered with ClinicalTrials.gov, number NCT01075698.


Assuntos
Proteína C-Reativa/metabolismo , Doenças Cardiovasculares/epidemiologia , Hipertensão/tratamento farmacológico , Idoso , Anti-Hipertensivos/farmacologia , Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Doenças Cardiovasculares/sangue , Feminino , Humanos , Hipertensão/sangue , Incidência , Japão , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores Sexuais
16.
Lab Invest ; 89(12): 1340-7, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19806081

RESUMO

Extracellular matrix (ECM) degradation is performed primarily by matrix metalloproteinases (MMPs). MMPs have recently been shown to regulate synaptic activity in the hippocampus and to affect memory and learning. The tissue inhibitor of metalloproteinase (Timp) is an endogenous factor that controls MMP activity by binding to the catalytic site of MMPs. At present, four Timp isotypes have been reported (Timp-1 through Timp-4) with 35-50% amino-acid sequence homology. Timp-3 is a unique member of Timp proteins in that it is bound to the ECM. In this study, we used the passive avoidance test, active avoidance test, and water maze test to examine the cognitive function in Timp-3 knockout (KO) mice. Habituation was evaluated using the open-field test. The water maze test showed that Timp-3 KO mice exhibit deterioration in cognitive function compared with wild-type (WT) mice. The open-field test showed decreased habituation of Timp-3 KO mice. Immunostaining of brain slices revealed the expression of Timp-3 in the hippocampus. In situ zymography of the hippocampus showed increased gelatinolytic activity in Timp-3 KO mice compared with WT mice. These results present the first evidence of Timp-3 involvement in cognitive function and hippocampal MMP activity in mice. Moreover, our findings suggest a novel therapeutic target to be explored for improvement of cognitive function in humans.


Assuntos
Aprendizagem da Esquiva/fisiologia , Hipocampo/enzimologia , Memória/fisiologia , Inibidor Tecidual de Metaloproteinase-3/deficiência , Animais , Gelatinases/metabolismo , Habituação Psicofisiológica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
17.
Sci Rep ; 9(1): 16589, 2019 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-31719604

RESUMO

The predictive value of serum adiponectin for hypertensive cardiovascular outcomes is unknown. This study was performed to investigate the association of adiponectin with incident cardiovascular and renal events (CV events) in hypertensive patients. We performed post-hoc analysis on 1,228 hypertensive patients enrolled in the ATTEMPT-CVD study, a prospective randomized study comparing the effects of two antihypertensive therapies. The participants were divided into quartiles of baseline serum total adiponectin or high molecular weight (HMW) adiponectin. Multivariable Cox proportional hazards analysis was performed to determine the prognostic factors associated with CV events. Kaplan-Meier analysis for CV events by quartiles of baseline total adiponectin showed that patients in the highest total adiponectin quartile (Q4) had more CV events (P = 0.0135). On the other hand, no significant difference was noted regarding the incidence of CV events among patients stratified by HMW adiponectin quartile (P = 0.2551). Even after adjustment for potential confounders, the highest total adiponectin quartile (Q4) remained independently associated with incident CV events in hypertensive patients (HR = 1.949: 95%CI 1.051-3.612; P = 0.0341). These results showed that total adiponectin, but not HMW adiponectin, was independently associated with the incidence of CV events in treated hypertensive patients, thereby highlighting total adiponectin as a valuable predictor for hypertensive cardiovascular outcomes.


Assuntos
Adiponectina/sangue , Anti-Hipertensivos/efeitos adversos , Doenças Cardiovasculares/diagnóstico , Hipertensão/tratamento farmacológico , Nefropatias/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/induzido quimicamente , Doenças Cardiovasculares/epidemiologia , Feminino , Seguimentos , Humanos , Hipertensão/patologia , Incidência , Nefropatias/sangue , Nefropatias/induzido quimicamente , Nefropatias/epidemiologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Fatores de Risco
18.
Hypertens Res ; 42(6): 883-891, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30664702

RESUMO

To investigate whether anemia is an independent risk factor for cardiovascular and renal events in hypertensive outpatients, we performed a subgroup analysis of the ATTEMPT-CVD study based on baseline hemoglobin. The ATTEMPT-CVD study was a multicenter, prospective, randomized study of hypertensive outpatients that compared the efficacy of angiotensin receptor blocker (ARB)-based antihypertensive treatment with non-ARB antihypertensive treatment over 3 years. In the present subanalysis, ATTEMPT-CVD study participants (n = 1213) were categorized into the anemic group and nonanemic group according to their baseline hemoglobin. We compared the anemic and nonanemic groups mainly in regard to the incidence of cardiovascular and renal events and blood pressure. We also performed a multivariable Cox proportional hazards analysis to determine the prognostic factors that were independently associated with cardiovascular and renal events. Of the 1213 patients enrolled in the ATTEMPT-CVD, 194 patients had anemia (mostly mild anemia) and 1019 patients did not. Blood pressure was well-controlled during the 3 years of antihypertensive therapy in both the anemic and nonanemic groups. However, the incidence of cardiovascular and renal events was significantly greater in the anemic group than in the nonanemic group (HR = 1.945: 95%CI 1.208-3.130; P = 0.0062). Even after adjustment, anemia was independently associated with cardiovascular and renal events (HR = 1.816: 95%CI 1.116-2.955; P = 0.0163) in overall hypertensive patients with well-controlled blood pressure. Anemia, even mild anemia, is an independent risk factor for cardiovascular and renal events in hypertensive outpatients whose blood pressure is well-controlled. Thus, anemia may be a novel therapeutic target for cardiovascular and renal diseases in hypertensive outpatients with anemia.


Assuntos
Anemia/complicações , Anemia/epidemiologia , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Hipertensão/complicações , Hipertensão/epidemiologia , Nefropatias/epidemiologia , Nefropatias/etiologia , Adulto , Bloqueadores do Receptor Tipo 1 de Angiotensina II/uso terapêutico , Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea , Feminino , Hemoglobinas/análise , Humanos , Hipertensão/tratamento farmacológico , Incidência , Estimativa de Kaplan-Meier , Masculino , Pacientes Ambulatoriais , Prognóstico , Estudos Prospectivos , Fatores de Risco
19.
Biochem Biophys Res Commun ; 377(4): 1097-101, 2008 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-18977203

RESUMO

Apop-1 is a novel protein identified in cultured atherosclerotic smooth muscle cells of ApoE-deficient mice, and the expression of the Apop-1 protein induces the death of cultured cells. Insulin-like growth factor-1 (IGF-1) is a well-characterized survival factor for VSMC; however, the interaction between Apop-1 and survival factor IGF-1 in the mediation of cell death is poorly understood. In this report, we show that the IGF-1 signaling cascade protects VSMC against Apop-1-induced death. Furthermore, our data indicate that the inhibition of Apop-1-induced death by IGF-1 is mediated by the activation of the PI3K/Akt signaling pathway.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Apoptose , Proteínas Mitocondriais/metabolismo , Músculo Liso Vascular/citologia , Músculo Liso Vascular/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Caspase 9/metabolismo , Células Cultivadas , Citocromos c/metabolismo , Ativação Enzimática , Fator de Crescimento Insulin-Like I/metabolismo , Fator de Crescimento Insulin-Like I/farmacologia , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/enzimologia , Músculo Liso Vascular/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo
20.
Arterioscler Thromb Vasc Biol ; 27(10): 2184-90, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17690318

RESUMO

OBJECTIVE: We identified a ubiquitin carboxyl-terminal hydrolase L1 (UCHL1) gene, which encodes a deubiquitinating enzyme and is expressed in the vasculature, by functional screening of a human endothelial cell (EC) cDNA library. UCHL1 is expressed in neurons, and abnormalities in UCHL1 are responsible for inherited Parkinson's disease via its effects on the ubiquitin-proteasome system. Therefore, the goal of present study was to clarify the role of the UCHL1 gene in vascular remodeling by evaluating nuclear factor-kappaB (NF-kappaB) inactivation in ECs and vascular smooth muscle cells (VSMCs). METHODS AND RESULTS: From Northern blot and immunohistochemical analysis, the UCHL1 gene was endogenously expressed in vascular ECs, VSMCs, and brain tissue. Expression of UCHL1 was markedly increased in the neointima of the balloon-injured carotid artery and was also present in atherosclerotic lesions from human carotid arteries. Overexpression of the UCHL1 gene significantly attenuated tumor necrosis factor (TNF)-alpha-induced NF-kappaB activity in vascular cells and increased inhibitor of kappa B-alpha (IkappaB-alpha), possibly through the attenuation of IkappaB-alpha ubiquitination, leading to decreased neointima in the balloon-injured artery. In contrast, knockdown of UCHL1 by small interfering RNA resulted in increased NF-kappaB activity in VSMCs. CONCLUSIONS: These data suggest that UCHL1 may partially attenuate vascular remodeling through inhibition of NF-kappaB activity.


Assuntos
Células Endoteliais/metabolismo , Proteínas I-kappa B/metabolismo , Músculo Liso Vascular/metabolismo , NF-kappa B/metabolismo , Processamento de Proteína Pós-Traducional , Ubiquitina Tiolesterase/metabolismo , Ubiquitina/metabolismo , Animais , Lesões das Artérias Carótidas/enzimologia , Lesões das Artérias Carótidas/etiologia , Lesões das Artérias Carótidas/metabolismo , Estenose das Carótidas/enzimologia , Cateterismo/efeitos adversos , Células Cultivadas , Modelos Animais de Doenças , Células Endoteliais/enzimologia , Humanos , Músculo Liso Vascular/enzimologia , Miócitos de Músculo Liso/enzimologia , Miócitos de Músculo Liso/metabolismo , Inibidor de NF-kappaB alfa , NF-kappa B/genética , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Interferência de RNA , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/metabolismo , Ratos , Fatores de Tempo , Transfecção , Fator de Necrose Tumoral alfa/metabolismo , Ubiquitina Tiolesterase/análise , Ubiquitina Tiolesterase/genética , Regulação para Cima
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