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1.
Mol Cell Biochem ; 478(3): 665-678, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36029453

RESUMO

Atherosclerotic morbidity is significantly higher in the diabetic population. Hyperglycemia, a typical feature of diabetes, has been proven to accelerate foam cell formation. However, the molecular mechanisms behind this process remain unclear. In this study, LPS and IFN-γ were used to convert THP-1-derived macrophages into M1 macrophages, which were then activated with ox-LDL in either high glucose or normal condition. We identified lipids within macrophages by Oil red O staining and total cholesterol detection. The genes involved in lipid absorption, efflux, inflammation, and metabolism were analyzed using qRT-PCR. The mechanisms of high glucose-induced foam cell formation were further investigated through metabolomics and transcriptomics analysis. We discovered that high glucose speed up lipid accumulation in macrophages (both lipid droplets and total cholesterol increased), diminished lipid efflux (ABCG1 down-regulation), and aggravated inflammation (IL1B and TNF up-regulation). Following multi-omics analysis, it was determined that glucose altered the metabolic and transcriptional profiles of macrophages, identifying 392 differently expressed metabolites and 293 differentially expressed genes, respectively. Joint pathway analysis suggested that glucose predominantly disrupted the glycerolipid, glycerophospholipid, and arachidonic acid metabolic pathways in macrophages. High glucose in the glyceride metabolic pathway, for instance, suppressed the transcription of triglyceride hydrolase (LIPG and LPL), causing cells to deposit excess triglycerides into lipid droplets and encouraging foam cell formation. More importantly, high glucose triggered the accumulation of pro-atherosclerotic lipids (7-ketocholesterol, lysophosphatidylcholine, and glycerophosphatidylcholine). In conclusion, this work elucidated mechanisms of glucose-induced foam cell formation via a multi-omics approach.


Assuntos
Aterosclerose , Multiômica , Humanos , Colesterol/metabolismo , Macrófagos/metabolismo , Células Espumosas/metabolismo , Lipoproteínas LDL/metabolismo , Aterosclerose/metabolismo , Triglicerídeos/metabolismo , Inflamação/metabolismo , Glucose/metabolismo
2.
Int Immunopharmacol ; 99: 107993, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34330059

RESUMO

Tumor necrosis factor α-induced protein 1 (TNFAIP1) has been documented as a vital regulator of apoptosis and oxidative stress under various pathological conditions. However, whether TNFAIP1 plays a role in myocardial ischemia/reperfusion (I/R) injury has not been well investigated. This work aimed to evaluate the possible role of TNFAIP1 in mediating myocardial I/R injury. Firstly, we demonstrated that TNFAIP1 expression was dramatically increased in rat cardiomyocytes following hypoxia/reoxygenation (H/R) in vitro, and in rat myocardial tissues following I/R treatment in vivo. Silencing of TNFAIP1 alleviated H/R-induced apoptosis, oxidative stress and inflammatory response in rat cardiomyocytes in vitro. Moreover, knockdown of TNFAIP1 ameliorated I/R-induced myocardial injury, infarction size, cardiac apoptosis, oxidative stress and inflammatory response in vivo. Further investigation elucidated that knockdown of TNFAIP1 enhanced the activation of nuclear factor erythroid 2-related factor 2 (Nrf2) signaling associated with modulation of the Akt/glycogen synthase kinase-3ß (GSK-3ß) pathway in vitro and in vivo. Inhibition of Akt markedly abrogated TNFAIP1-knockdown-mediated Nrf2 activation in cardiomyocytes following H/R injury. In addition, suppression of Nrf2 significantly diminished TNFAIP1-knockdown-induced cardioprotective effects in H/R-exposed cardiomyocytes. In summary, this work elucidates that inhibition of TNFAIP1 ameliorates myocardial I/R injury by potentiating Nrf2 signaling via the modulation of the Akt/GSK-3ß pathway. Our study highlights a vital role of the TNFAIP1/Akt/GSK-3ß/Nrf2 pathway in mediating myocardial I/R injury and suggests TNFAIP1 as an attractive target for treatment of this disease.


Assuntos
Proteínas de Transporte/genética , Inflamação/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/fisiologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Apoptose/efeitos dos fármacos , Células Cultivadas , Citocinas/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Compostos Heterocíclicos com 3 Anéis/farmacologia , Hipóxia , Modelos Animais , Miócitos Cardíacos , Fator 2 Relacionado a NF-E2/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Fator de Transcrição STAT1 , Transdução de Sinais
3.
J Cell Biochem ; 120(6): 10155-10163, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30635942

RESUMO

Finding ways to reduce myocardial ischemia/reperfusion injury in the process of myocardial infarction has been an area of intense study in the field of heart disease. Recent studies have shown that long noncoding RNA (lncRNA) and autophagy play important roles in cardiovascular diseases. In our study, software analysis and dual-luciferase reporter assays have shown that miR-30a has binding sites on both AK088388 and Beclin-1. Continuing experiments found that miR-30a expression is downregulated, while the expressions of AK088388, Beclin-1, and LC3-II are upregulated in hypoxia/reoxygenation (H/R) cardiomyocytes; miR-30a inhibits the expression of AK088388, Beclin-1, and LC3-II in H/R cardiomyocytes, while AK088388 promotes the expression of Beclin-1 and LC3-II and inhibits miR-30a expression. AK088388 small interfering RNA and miR-30a mimics can promote the viability of H/R cardiomyocytes, reduce lactate dehydrogenase release, and reduce apoptosis. Mutations of the miR-30a binding site in AK088388 could not block the effects of miR-30a mentioned above. Therefore, AK088388 can competitively bind to miR-30a, promoting the expression of Beclin-1 and LC3-II, autophagy, and eventually cell damage. This finding provides new evidence for understanding the role of lncRNA in myocardial ischemia/reperfusion injury.


Assuntos
Autofagia/genética , Proteína Beclina-1/genética , Regulação da Expressão Gênica , MicroRNAs/genética , Miócitos Cardíacos/metabolismo , RNA Longo não Codificante/genética , Animais , Apoptose/genética , Proteína Beclina-1/metabolismo , Hipóxia Celular , Linhagem Celular , Sobrevivência Celular/genética , Células Cultivadas , Camundongos , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Infarto do Miocárdio/genética , Infarto do Miocárdio/metabolismo , Miócitos Cardíacos/patologia , Oxigênio/metabolismo , Interferência de RNA
4.
Zhonghua Nan Ke Xue ; 25(8): 724-729, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-32227716

RESUMO

OBJECTIVE: To explore the content and mode of extended specialized outpatient nursing care (SONC) in assisted reproduction clinics in the joint efforts of the level-Ⅲ grade-A hospital and lower-level hospitals. METHODS: We enrolled 300 infertility patients for this study, 150 from the hospitals of our Integrated Healthcare System (IHCS) and the other 150 from other local hospitals, the former receiving extended SONC based on wisdom medicine of the IHCS (the experimental group), and the latter conventional SONC (the control group). At the end of the treatment cycle, we compared the frequency of clinic visits, knowledge of relevant requirements (such as the procedure of consultation, timely completion of examinations, timely initiation of the treatment cycle, and correct execution of doctor's advice), and scores on the Medical Coping Modes Questionnaire and quality of life (QOL) between the two groups of patients. RESULTS: Compared with the control group, the experimental group showed a significantly lower frequency of clinic visits (P < 0.05), better knowledge of relevant requirements (P < 0.05), higher confrontation score (P < 0.05), lower resignation score (P < 0.05), and higher QOL score (P < 0.05). CONCLUSIONS: SONC based on wisdom medicine of IHCS in the assisted reproduction clinic is conducive to synchronization of thinking, sharing of knowledge and information, seamless connection between upper- and lower-level hospitals, and hence the provision of homogenous nursing care.


Assuntos
Assistência Ambulatorial , Prestação Integrada de Cuidados de Saúde , Enfermagem , Pacientes Ambulatoriais , Técnicas de Reprodução Assistida , Humanos , Qualidade de Vida , Inquéritos e Questionários
5.
Int Immunopharmacol ; 62: 203-211, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30015240

RESUMO

Monocytes recruited and adhering to the inflamed arteries are crucial for atherosclerosis development. Here, we report the role of zinc (Zn2+) homeostasis in monocyte adhesion and recruitment. By comparing the expression levels of Zn2+ transporters between non-adhering and adhering monocytes, we found that the Zn2+ importer ZIP8 was specifically upregulated in monocytes adhering to the aortas ex-vivo. Although the overexpression of ZIP8 increased the absorption of Zn2+, Fe2+ and Cd2+ in monocytes, only Zn2+ supplementation was demonstrated capable of promoting the adhesion of monocytes to endothelial monolayers in vitro. In addition, we confirmed the role of ZIP8-dependent Zn2+ influx in promoting monocyte adhesion to the aortas ex-vivo. More importantly, the enforced expression of ZIP8 increased monocyte adhesion and recruitment to the nascent atherosclerotic lesions in ApoE-/- mice. Overall, our results suggest that the Zn2+ influx in monocytes regulated by ZIP8 is a novel factor determining their adhesion and recruitment to atherosclerotic lesions, and that targeting ZIP8 or Zn2+ homeostasis may represent a novel strategy to interfere these activities.


Assuntos
Aorta/metabolismo , Proteínas de Transporte de Cátions/metabolismo , Adesão Celular , Doença da Artéria Coronariana/metabolismo , Monócitos/metabolismo , Zinco/metabolismo , Animais , Aorta/patologia , Apolipoproteínas E/genética , Proteínas de Transporte de Cátions/genética , Adesão Celular/genética , Linhagem Celular , Doença da Artéria Coronariana/genética , Doença da Artéria Coronariana/patologia , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL , Camundongos Knockout , Monócitos/patologia , Regulação para Cima
6.
Mol Med Rep ; 16(4): 4871-4878, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28791379

RESUMO

Oxidative stress and inflammation are involved in the pathogenesis of atherosclerosis. Calcium channel blockers (CCBs) inhibit the development of atherosclerosis, although the underlying molecular basis has not been completely elucidated. The present study was designed to investigate the effects of felodipine, a CCB, on inflammation and oxidative stress in human umbilical vein endothelial cells (HUVECs) and to examine the underlying mechanisms of action. Oxidized low­density lipoprotein (ox­LDL) was used to induce an inflammatory response in HUVECs. The effects of felodipine were investigated by measuring the content of nitric oxide (NO) and reactive oxygen species (ROS), the mRNA and protein levels of intercellular adhesion molecule 1 (ICAM­1) and vascular cell adhesion protein 1 (VCAM­1), and the mRNA levels of endothelial NO synthase (eNOS) and inducible NO synthase (iNOS), in addition to the adhesion ability of U937 cells to HUVECs. ROS and NO levels were significantly increased in HUVECs following 24­h treatment with 25 mg/l ox­LDL (P<0.01). The increase in ROS was reversed by treatment with felodipine. In addition, NO levels were increased following treatment with 1 µmol/l felodipine (P<0.05). The mRNA expression of ICAM­1, VCAM­1, eNOS and iNOS was increased (P<0.05). Administration of 0.1 µM felodipine significantly decreased the expression of ICAM­1, VCAM­1, and iNOS (P<0.05). The number of U937 cells adhered to ox­LDL­treated HUVECs was significantly increased compared with control, which was reversed by felodipine (0.1 µM). In conclusion, felodipine was demonstrated to inhibit oxidative stress and inflammatory responses, suggesting that it may be used to treat atherosclerosis.


Assuntos
Felodipino/farmacologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Inflamação/metabolismo , Lipoproteínas LDL/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Células Cultivadas , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Inflamação/tratamento farmacológico , Inflamação/genética , Molécula 1 de Adesão Intercelular/genética , Molécula 1 de Adesão Intercelular/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico Sintase Tipo III/genética , Óxido Nítrico Sintase Tipo III/metabolismo , Molécula 1 de Adesão de Célula Vascular/genética , Molécula 1 de Adesão de Célula Vascular/metabolismo
7.
Zhonghua Nan Ke Xue ; 23(6): 536-539, 2017 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-29722947

RESUMO

OBJECTIVE: To investigate the benefits of nursing care service in the assisted reproduction clinic to self-cycle-management and self-efficiency of the outpatients with infertility. METHODS: We randomly divided 600 females preliminarily diagnosed with infertility into a control and an experimental group, 288 in the former and 285 in the latter group excluding those whose husbands had azoospermia. For the women patients of the experimental group, we conducted nursing care intervention concerning related knowledge, skills, diet, excise, medication, and psychology, by one-to-one consultation, individualized or group communication, establishing files, telephone follow-up, and wechat guidance. After 3 months of intervention, we compared the compliance of medical visits, effectiveness of cycle management, sense of self-efficiency, satisfaction, and anxiety score between the two groups of patients. RESULTS: In comparison with the controls, the patients of the experimental group showed significantly better knowledge about assisted reproduction and higher effectiveness of self-cycle-management, self-efficiency, and satisfaction (P <0.05), but a markedly lower degree of anxiety (P <0.05). CONCLUSIONS: Nursing care service in the assisted reproduction clinic can improve the compliance of medical visits, effectiveness of self-cycle-management, self-efficiency, and satisfaction and reduce the anxiety of the patients.


Assuntos
Conhecimentos, Atitudes e Prática em Saúde , Infertilidade/enfermagem , Ciclo Menstrual , Técnicas de Reprodução Assistida/psicologia , Ansiedade/prevenção & controle , Dieta , Exercício Físico , Feminino , Humanos , Infertilidade/psicologia , Cooperação do Paciente , Satisfação do Paciente , Autoeficácia
8.
Shock ; 48(2): 201-208, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28002238

RESUMO

OBJECTIVES: Percutaneous coronary interventions (PCIs) save countless acute myocardial infarction (AMI) patients. However, endothelial injury is still an inevitable complication. Circulating microparticles (MPs) play important roles in vascular dysfunction. Whether PCI affects function of MPs remains unclear. METHODS: MPs were obtained from AMI patients (n = 38) both preoperatively and 24 h after PCI, and healthy subjects (n = 20). MPs origins were tested by flow cytometry. Rat thoracic aortas were incubated with MPs to determine the effects of MPs on phosphorylation of endothelial nitric oxide synthase (eNOS), caveolin-1 expression, eNOS association with heat shock protein 90 (Hsp90), generation of nitric oxide (NO) and superoxide anion (O2), and endothelial-dependent vasodilatation. RESULTS: Compared with healthy subjects, MP concentrations increased in AMI patients. Undergoing PCI had no further effect on MPs concentration, but it results in increased endothelial-derived MPs proportion and decreased platelet-derived MP ratio. MPs from AMI patients decreased eNOS phosphorylation at Ser1177, increased eNOS phosphorylation at T495 and caveolin-1 expression, decreased eNOS association with Hsp90, decreased NO production but increased (O2) generation, damaged endothelial-dependent vasodilatation. All of these effects of MPs were strengthened by PCI. CONCLUSIONS: PCI further enhances the vascular injury effect of MPs. Circulating MPs may be a potential therapeutic target for patients undergoing PCI.


Assuntos
Micropartículas Derivadas de Células , Infarto do Miocárdio , Óxido Nítrico Sintase Tipo III/biossíntese , Intervenção Coronária Percutânea , Vasodilatação , Adulto , Animais , Micropartículas Derivadas de Células/metabolismo , Micropartículas Derivadas de Células/transplante , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/sangue , Infarto do Miocárdio/cirurgia , Ratos , Ratos Sprague-Dawley
9.
Chin Med J (Engl) ; 128(7): 969-75, 2015 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-25836620

RESUMO

OBJECTIVE: The objective was to provide a brief history of J wave syndromes and to summarize our current understanding of their molecular, ionic, cellular mechanisms, and clinical features. We will also discuss the existing debates and further direction in basic and clinical research for J wave syndromes. DATA SOURCES: The publications on key words of "J wave syndromes", "early repolarization syndrome (ERS)", "Brugada syndrome (BrS)" and "ST-segment elevation myocardial infarction (STEMI)" were comprehensively reviewed through search of the PubMed literatures without restriction on the publication date. STUDY SELECTION: Original articles, reviews and other literatures concerning J wave syndromes, ERS, BrS and STEMI were selected. RESULTS: J wave syndromes were firstly defined by Yan et al. in a Chinese journal a decade ago, which represent a spectrum of variable phenotypes characterized by appearance of prominent electrocardiographic J wave including ERS, BrS and ventricular fibrillation (VF) associated with hypothermia and acute STEMI. J wave syndromes can be inherited or acquired and are mechanistically linked to amplification of the transient outward current (I to )-mediated J waves that can lead to phase 2 reentry capable of initiating VF. CONCLUSIONS: J wave syndromes are a group of newly highlighted clinical entities that share similar molecular, ionic and cellular mechanism and marked by amplified J wave on the electrocardiogram and a risk of VF. The clinical challenge ahead is to identify the patients with J wave syndromes who are at risk for sudden cardiac death and determine the alternative therapeutic strategies to reduce mortality.


Assuntos
Síndrome de Brugada/fisiopatologia , Síndrome de Brugada/diagnóstico , Eletrocardiografia , Humanos , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/fisiopatologia
10.
Chin Med J (Engl) ; 125(3): 428-33, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22490397

RESUMO

BACKGROUND: Cardiac resynchronization therapy (CRT) with biventricular pacing improves cardiac function, functional capacity and quality of life in selected patients with heart failure. The current study aimed to evaluate the efficacy of the intracardiac electrogram (IEGM)-based optimization method, QuickOpt(TM), in Chinese patients treated with CRT. METHODS: Aortic time velocity integrals (AVTI) achieved at the sensed atrioventricular (AV), paced AV and interventricular (VV) interval settings recommended by both QuickOpt(TM) and standard echocardiographic optimization were measured in 101 patients. Consistency and the strength of the relationship between the two timing cycle optimization methods were assessed by intra-class correlation coefficient (ICC). RESULTS: The ICC showed good agreement and correlation with what the AVTI achieved at the optimal sensed AV (ICC = 0.9683 (0.9535 - 0.9785)), paced AV (ICC = 0.9642 (0.9475 - 0.9757)) and VV (ICC = 0.9730 (0.9602 - 0.9817)) interval settings determined by the two optimization methods. The average time required by echocardiographic optimization and by QuickOpt(TM) were (78.32 ± 32.40) minutes and (1.98 ± 1.64) minutes respectively (P < 0.0001). CONCLUSION: The QuickOpt(TM) algorithm provides a quicker, simpler and reliable alternative to the standard method for timing cycle optimization.


Assuntos
Terapia de Ressincronização Cardíaca/métodos , Técnicas Eletrofisiológicas Cardíacas/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Insuficiência Cardíaca/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
11.
Burns ; 38(4): 568-72, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22103989

RESUMO

A statistical survey was conducted at the Burn Unit of the Tangdu Hospital, Shaanxi, China, during the 10-year period from January 2000 to December 2009. In this retrospective study, 383 patients who admitted to our burn unit because of electrical trauma were included. Data including the patient's general condition, clinical presentation, complications and operation times was collected retrospectively and analyzed with epidemiological methods. Subjects in our collective were predominantly male (90.3%, n=346/383) and were composed by those who injured in work-related incidents (78.3%, n=300/383), rural individuals (58.2%, n=223/383) and students (9.4%, n=36/383). High voltage was directly correlated to severity clinical complications, and amputation. The percentage of myocardial impairment was 79.3% (n=92/116) among patients who suffered with electrical current through heart tissue. Along with the more developed east area of China, electrical injuries are becoming a growing concern of the developing West part in China as well. Electrical injuries induce serious tissue damage, need long hospital stay, and result in high rate of permanent disability and economic hardship for the afflicted families. A competent prevention program needs to be developed to address this problem.


Assuntos
Acidentes de Trabalho/estatística & dados numéricos , Queimaduras por Corrente Elétrica/epidemiologia , Adolescente , Adulto , Distribuição por Idade , Queimaduras por Corrente Elétrica/etiologia , Queimaduras por Corrente Elétrica/prevenção & controle , Criança , China/epidemiologia , Feminino , Humanos , Incidência , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença , Distribuição por Sexo , Adulto Jovem
12.
Nan Fang Yi Ke Da Xue Xue Bao ; 29(4): 711-3, 2009 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-19403402

RESUMO

OBJECTIVE: To investigate the changes in peripheral blood bone marrow stem cells and tumor necrosis factor-alpha gene expression in the ischemic myocardium in rabbit models of hibernating myocardium. METHODS: Twenty-four male Japanese white rabbits were randomized into 4 groups, including a sham-operated group and 3 model groups with hibernating myocardium induced by partial ligation of the left anterior descending coronary artery. The percentage of CD34-positive cells in the peripheral blood was evaluated by flow cytometry, and TNF-alpha mRNA expression in the ischemic myocardium was determined by real-time RT-PCR in the 3 model groups (at 3, 7, or 28 days after the operation) and in the sham-operated group. RESULTS: In rabbits with partial ligation of the left anterior descending coronary artery, the percentage of CD34-positive cells in the peripheral blood and myocardial TNF-alpha mRNA expression were significantly increased at 3 and 7 days after the operation in comparison with those in the sham-operated group and those at 28 days postoperatively (P<0.01). No significant differences were found in the percentage of CD34 positive cells or myocardial TNF-alpha mRNA expression between the sham-operated group and the rabbits 28 days after the coronary artery ligation (P>0.05). CONCLUSION: Bone marrow stem cell can be mobilized into the peripheral blood in rabbit hibernating myocardium model possibly by increasing TNF-alpha gene expression in the ischemic myocardium.


Assuntos
Células da Medula Óssea/citologia , Regulação da Expressão Gênica , Mobilização de Células-Tronco Hematopoéticas , Hibernação , Isquemia Miocárdica/metabolismo , Isquemia Miocárdica/terapia , Fator de Necrose Tumoral alfa/genética , Animais , Antígenos CD34/metabolismo , Vasos Coronários/cirurgia , Modelos Animais de Doenças , Ligadura , Masculino , Isquemia Miocárdica/fisiopatologia , Isquemia Miocárdica/cirurgia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Coelhos
13.
Clin Exp Pharmacol Physiol ; 36(8): 822-7, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19215240

RESUMO

1. Congenital long QT syndrome (LQTS) is a genetically heterogeneous disease. The aim of the present study was to identify the gene mutation in a Chinese family with LQTS and investigate the functional changes associated with the mutation. 2. Polymerase chain reaction and DNA sequencing were used to screen for the KCNH2 mutation in the proband. A mutant F463L HERG channel was expressed in HEK293 cells using a lipofectamine method. The IKr current was recorded using the whole-cell voltage clamp technique. Expression of HERG protein was detected by western blotting and the subcellular location of HERG channels in cell was analysed by confocal microscopy. 3. The novel heterozygous missense mutation F463L in KCNH2 was detected. We found that the F463L mutation did not lead to any expression of detectable I(Kr) current, which was consistent with western blotting analysis indicating that the F463L mutation only expressed a band at 135 kDa. When coexpressed with wild-type HERG, F463L HERG exhibited strong dominant-negative current suppression, resulting in a decrease in I(Kr) current density, and induced a positive shift in the voltage dependence of activation, as well as interference with trafficking of wild-type channel protein. The processing of the F463L channels was partly corrected in cells incubated in E4031. In addition, confocal microscopy demonstrated that F463L subunits could be inserted into the cell membrane when forming heteromultimeric channels with wild-type channel subunits. 4. The results of the present study suggest that the F463L mutation leads to loss of function in HERG through a dominant-negative effect caused by impaired trafficking of the channel.


Assuntos
Canais de Potássio Éter-A-Go-Go/genética , Leucina/genética , Síndrome do QT Longo/genética , Mutação de Sentido Incorreto , Fenilalanina/genética , Canais de Potássio de Abertura Dependente da Tensão da Membrana/metabolismo , Sequência de Aminoácidos , Substituição de Aminoácidos , Sequência de Bases , Western Blotting , Linhagem Celular , Citosina/metabolismo , Canal de Potássio ERG1 , Eletrocardiografia , Retículo Endoplasmático/genética , Retículo Endoplasmático/metabolismo , Canais de Potássio Éter-A-Go-Go/metabolismo , Heterozigoto , Humanos , Síndrome do QT Longo/congênito , Síndrome do QT Longo/metabolismo , Microscopia Confocal , Dados de Sequência Molecular , Técnicas de Patch-Clamp , Linhagem , Subunidades Proteicas , Transporte Proteico/genética , Timina/metabolismo , Transfecção
15.
Nan Fang Yi Ke Da Xue Xue Bao ; 27(12): 1878-9, 2007 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-18159009

RESUMO

OBJECTIVE: To investigate the effect of short-term intensive treatment with insulin pump on beta cell function and the mechanism of oxidative stress in newly diagnosed type 2 diabetic patients. METHODS: Totally 120 newly diagnosed type 2 diabetic patients were treated with insulin pump for 2 weeks. The levels of fasting plasma glucose (FPG), 2-hour postprandial blood glucose (2hPG), homeostatic model assessment of the insulin secretion index and insulin resistance index (HOMA-beta and HOMAIR, respectively), blood malondialdehyde (MDA) and superoxide dismutase (SOD) were measured before and after insulin pump treatment. RESULTS: After insulin pump treatment, FPG, 2hPG, HOMAIR and blood MDA were significantly decreased (P<0.01), while HOMA-beta and blood SOD were significantly increased (P<0.01). CONCLUSION: Short-term intensive treatment with insulin pump can effectively improve beta cell function probably by decreasing oxidative stress in newly diagnosed type 2 diabetic patients.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Sistemas de Infusão de Insulina , Células Secretoras de Insulina/fisiologia , Estresse Oxidativo , Adulto , Glicemia , Diabetes Mellitus Tipo 2/sangue , Feminino , Humanos , Insulina/sangue , Masculino , Malondialdeído/sangue , Pessoa de Meia-Idade , Superóxido Dismutase/sangue
16.
Chin Med J (Engl) ; 118(23): 1945-51, 2005 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-16336829

RESUMO

BACKGROUND: Little information is available regarding the effect of angiotensin II (Ang II) on the bumetanide-sensitive sodium-potassium-2 chloride cotransporter (NKCC2), the thiazide-sensitive sodium-chloride cotransporter (NCC), and the Cl- channel (CLC)-K2 at both mRNA and protein expression level in Ang II-induced hypertensive rats. This study was conducted to investigate the influence of Ang II with chronic subpressor infusion on nephron-specific gene expression of NKCC2, NCC and CLC-K2. METHODS: Sprague Dawleys rats were treated subcutaneously with either Ang II (100 ng.kg-1.min-1) or vehicle for 14 days. Expression of NKCC2, NCC and CLC-K2 mRNA in kidneys was determined by real time polymerase chain reaction (PCR). Western blotting analysis was used to measure NKCC2 and NCC protein expression. RESULTS: Ang II significantly increased blood pressure and up-regulated NKCC2 mRNA and protein expression in the kidney. Expression of CLC-K2 mRNA in the kidney increased 1.6 fold (P < 0.05). There were no changes in NCC mRNA or protein expression in AngII-treated rats versus control. CONCLUSIONS: Chronic subpressor Ang II infusion can significantly alter NKCC2 and CLC-K2 mRNA expression in the kidney, and protein abundance of NKCC2 in kidney is positively regulated by Ang II. These effects may contribute to enhanced renal Na+ and Cl- reabsorption in response to Ang II.


Assuntos
Angiotensina II/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Hipertensão/induzido quimicamente , Simportadores de Cloreto de Sódio-Potássio/genética , Animais , Pressão Sanguínea/efeitos dos fármacos , Hipertensão/metabolismo , Masculino , RNA Mensageiro/análise , Ratos , Ratos Sprague-Dawley , Membro 1 da Família 12 de Carreador de Soluto
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