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1.
Zhongguo Dang Dai Er Ke Za Zhi ; 25(2): 172-178, 2023 Feb 15.
Artigo em Zh | MEDLINE | ID: mdl-36854694

RESUMO

OBJECTIVES: To investigate the change in the distribution of memory B cell subsets in children with frequently relapsing nephrotic syndrome (FRNS) during the course of the disease. METHODS: A total of 35 children with primary nephrotic syndrome (PNS) who attended the Department of Pediatrics of the Affiliated Hospital of Xuzhou Medical University from October 2020 to October 2021 were enrolled as subjects in this prospective study. According to the response to glucocorticoid (GC) therapy and frequency of recurrence, the children were divided into two groups: FRNS (n=20) and non-FRNS (NFRNS; n=15). Fifteen children who underwent physical examination were enrolled as the control group. The change in memory B cells after GC therapy was compared between groups, and its correlation with clinical indicators was analyzed. RESULTS: Before treatment, the FRNS and NFRNS groups had significantly increased percentages of total B cells, total memory B cells, IgD+ memory B cells, and IgE+ memory B cells compared with the control group, and the FRNS group had significantly greater increases than the NFRNS group (P<0.05); the FRNS group had a significantly lower percentage of class-switched memory B cells than the NFRNS and control groups (P<0.05). After treatment, the FRNS and NFRNS groups had significant reductions in the percentages of total B cells, total memory B cells, IgM+IgD+ memory B cells, IgM+ memory B cells, IgE+ memory B cells, IgD+ memory B cells, and IgG+ memory B cells (P<0.05) and a significant increase in the percentage of class-switched memory B cells (P<0.05). The FRNS group had a significantly higher urinary protein quantification than the NFRNS and control groups (P<0.05) and a significantly lower level of albumin than the control group (P<0.05). In the FRNS group, urinary protein quantification was negatively correlated with the percentage of class-switched memory B cells and was positively correlated with the percentage of IgE+ memory B cells (P<0.05). CONCLUSIONS: Abnormal distribution of memory B cell subsets may be observed in children with FRNS, and the percentages of IgE+ memory B cells and class-switched memory B cells can be used as positive and negative correlation factors for predicting recurrence after GC therapy in these children.


Assuntos
Subpopulações de Linfócitos B , Síndrome Nefrótica , Criança , Humanos , Subpopulações de Linfócitos B/metabolismo , Imunoglobulina E , Imunoglobulina M , Síndrome Nefrótica/tratamento farmacológico , Síndrome Nefrótica/imunologia , Estudos Prospectivos , Glucocorticoides/uso terapêutico
2.
J Cell Mol Med ; 23(11): 7566-7580, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31517441

RESUMO

Myocardial ischaemia (MI) remains a major cause of death and disability worldwide. Accumulating evidence suggests a significant role for innate immunity, in which the family of toll-like receptors (TLRs) acts as an essential player. We previously reported and reviewed the changes of Tlr expression in models of MI. However, the underlying mechanisms regulating Tlr expression in MI remain unclear. The present study first screened transcription factors (TFs) that potentially regulate Tlr gene transcription based on in silico analyses followed by experimental verification, using both in vivo and in vitro models. Forkhead box C1 (FOXC1) was identified as a putative TF, which was highly responsive to MI. Next, by focusing on two representative TLR subtypes, an intracellular subtype TLR3 and a cell-surface subtype TLR4, the regulation of FOXC1 on Tlr expression was investigated. The overexpression or knockdown of FoxC1 was observed to up- or down-regulate Tlr3/4 mRNA and protein levels, respectively. A dual-luciferase assay showed that FOXC1 trans-activated Tlr3/4 promoter, and a ChIP assay showed direct binding of FOXC1 to Tlr3/4 promoter. Last, a functional study of FOXC1 was performed, which revealed the pro-inflammatory effects of FOXC1 and its destructive effects on infarct size and heart function in a mouse model of MI. The present study for the first time identified FOXC1 as a novel regulator of Tlr expression and described its function in MI.


Assuntos
Fatores de Transcrição Forkhead/metabolismo , Isquemia Miocárdica/genética , Receptores Toll-Like/genética , Regulação para Cima/genética , Animais , Animais Recém-Nascidos , Citocinas/metabolismo , Modelos Animais de Doenças , Técnicas de Silenciamento de Genes , Humanos , Inflamação/genética , Inflamação/patologia , Mediadores da Inflamação/metabolismo , Camundongos , Regiões Promotoras Genéticas , Ligação Proteica/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Receptores Toll-Like/metabolismo
3.
J Cell Mol Med ; 22(1): 395-408, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28945004

RESUMO

Toll-like receptors (TLRs) are essential immunoreceptors involved in host defence against invading microbes. Recent studies indicate that certain TLRs activate immunological autophagy to eliminate microbes. It remains unknown whether TLRs regulate autophagy to play a role in the heart. This study examined this question. The activation of TLR3 in cultured cardiomyocytes was observed to increase protein levels of autophagic components, including LC3-II, a specific marker for autophagy induction, and p62/SQSTM1, an autophagy receptor normally degraded in the final step of autophagy. The results of transfection with a tandem mRFP-GFP-LC3 adenovirus and use of an autophagic flux inhibitor chloroquine both suggested that TLR3 in cardiomyocytes promotes autophagy induction without affecting autophagic flux. Gene-knockdown experiments showed that the TRIF-dependent pathway mediated the autophagic effect of TLR3. In the mouse model of chronic myocardial infarction, persistent autophagy was observed, concomitant with up-regulated TLR3 expression and increased TLR3-Trif signalling. Germline knockout (KO) of TLR3 inhibited autophagy, reduced infarct size, attenuated heart failure and improved survival. These protective effects were abolished by in vivo administration of an autophagy inducer rapamycin. Similar to the results obtained in cultured cardiomyocytes, TLR3-KO did not prevent autophagic flux in mouse heart. Additionally, this study failed to detect the involvement of inflammation in TLR3-KO-derived protection, as wild-type and TLR3-KO hearts were comparable in inflammatory activity. It is concluded that up-regulated TLR3 expression and signalling contributes to persistent autophagy following MI, which promotes heart failure and lethality.


Assuntos
Autofagia , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/metabolismo , Infarto do Miocárdio/complicações , Receptor 3 Toll-Like/metabolismo , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Animais , Autofagia/efeitos dos fármacos , Células Cultivadas , Citocinas/metabolismo , Insuficiência Cardíaca/patologia , Camundongos Knockout , Miocárdio/metabolismo , Miocárdio/patologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Miócitos Cardíacos/ultraestrutura , Poli I-C/farmacologia , Ratos Sprague-Dawley , Receptor 3 Toll-Like/agonistas
4.
J Cell Mol Med ; 19(12): 2728-40, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26290459

RESUMO

It remains unclear whether and how cardiomyocytes contribute to the inflammation in chronic heart failure (CHF). We recently reviewed the capacity of cardiomyocytes to initiate inflammation, by means of expressing certain immune receptors such as toll-like receptors (TLRs) that respond to pathogen- and damage-associated molecular patterns (PAMP and DAMP). Previous studies observed TLR4-mediated inflammation within days of myocardial infarction (MI). This study examined TLR4 expression and function in cardiomyocytes of failing hearts after 4 weeks of MI in rats. The increases of TLR4 mRNA and proteins, as well as inflammatory cytokine production, were observed in both the infarct and remote myocardium. Enhanced immunostaining for TLR4 was observed in cardiomyocytes but not infiltrating leucocytes. The injection of lentivirus shRNA against TLR4 into the infarcted heart decreased inflammatory cytokine production and improved heart function in vivo. Accordingly, in cardiomyocytes isolated from CHF hearts, increases of TLR4 mRNA and proteins were detected. More robust binding of TLR4 with lipopolysaccharide (LPS), a PAMP ligand for TLR4, and heat shock protein 60 (HSP60), a DAMP ligand for TLR4, was observed in CHF cardiomyocytes under a confocal microscope. The maximum binding capacity (Bmax ) of TLR4 was increased for LPS and HSP60, whereas the binding affinity (Kd) was not significantly changed. Furthermore, both LPS and HSP60 induced more robust production of inflammatory cytokines in CHF cardiomyocytes, which was reduced by TLR4-blocking antibodies. We conclude that the expression, ligand-binding capacity and pro-inflammatory function of cardiomyocyte TLR4 are up-regulated after long-term MI, which promote inflammation and exacerbate heart failure.


Assuntos
Insuficiência Cardíaca/metabolismo , Infarto do Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Receptor 4 Toll-Like/metabolismo , Regulação para Cima , Animais , Western Blotting , Células Cultivadas , Chaperonina 60/metabolismo , Doença Crônica , Insuficiência Cardíaca/genética , Inflamação/genética , Inflamação/metabolismo , Interleucina-6/genética , Interleucina-6/metabolismo , Lipopolissacarídeos/metabolismo , Masculino , Microscopia Confocal , Proteínas Mitocondriais/metabolismo , Infarto do Miocárdio/genética , Miocárdio/metabolismo , Miocárdio/patologia , Ligação Proteica , Interferência de RNA , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Tempo , Receptor 4 Toll-Like/genética , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
5.
Zhong Yao Cai ; 38(5): 972-4, 2015 May.
Artigo em Zh | MEDLINE | ID: mdl-26767289

RESUMO

OBJECTIVE: To study the chemical constituents from root of Artocarpus styracifolius. METHODS: Tne constituents were isolated from the root of Artocarpus styracifolius by column chromatography over silica gel, RP-18 silica gel, MCI GEL CHP-20P, macroporous resin HP-20, Sephadex LH-20, Toyopearl HW-40C and by preparative HPLC. Their structures were elucidated by analysis of physical and chemical properties and spectral data. RESULTS: Nine compounds were isolated and their structures were identified as p-hydroxy benzoic acid (1), syringic acid (2), 2,4-dihydroxy benzaldehyde (3), (+)-lyoniresinol (4), 5,5'-dimethoxysecoisolariciresinol (5), (+)- syringaresinol (6), scopoletin (7), xylarolide (8) and trans-oxyresveratrol (9). CONCLUSION: Compounds 2, 5, 6 and 8 are isolated from Moraceae for the first time. Compounds 1, 4 and 7 are firstly characterized in the genus Artocarpus, compounds 3 and 9 are characterized in Artocarpus styracifolius for the first time.


Assuntos
Artocarpus/química , Compostos Fitoquímicos/análise , Raízes de Plantas/química , Cromatografia Líquida de Alta Pressão , Furanos , Ácido Gálico/análogos & derivados , Lignanas , Extratos Vegetais , Escopoletina , Estilbenos
6.
Am J Physiol Heart Circ Physiol ; 307(2): H182-90, 2014 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-24838502

RESUMO

The rostral ventrolateral medulla (RVLM) plays a key role in cardiovascular regulation. It has been reported that tonically active glutamatergic input to the RVLM is increased in hypertensive rats, whereas angiotensin-converting enzyme 2 (ACE2) in the brain has been suggested to be beneficial to hypertension. This study was designed to determine the effect of ACE2 gene transfer into the RVLM on tonically active glutamatergic input in spontaneously hypertensive rats (SHRs). Lentiviral particles containing enhanced green fluorescent protein (lenti-GFP) or ACE2 (lenti-ACE2) were injected bilaterally into the RVLM. Both protein expression and activity of ACE2 in the RVLM were increased in SHRs after overexpression of ACE2. A significant reduction in blood pressure and heart rate in SHRs was observed 6 wk after lenti-ACE2 injected into the RVLM. The concentration of glutamate in microdialysis fluid from the RVLM was significantly reduced by an average of 61% in SHRs with lenti-ACE2 compared with lenti-GFP. ACE2 overexpression significantly attenuated the decrease in blood pressure and renal sympathetic nerve activity evoked by bilateral injection of the glutamate receptor antagonist kynurenic acid (2.7 nmol in 100 nl) into the RVLM in SHRs. Therefore, we suggest that ACE2 overexpression in the RVLM attenuates the enhanced tonically active glutamatergic input in SHRs, which may be an important mechanism underlying the beneficial effect of central ACE2 to hypertension.


Assuntos
Ácido Glutâmico/metabolismo , Hipertensão/terapia , Bulbo/enzimologia , Peptidil Dipeptidase A/biossíntese , Enzima de Conversão de Angiotensina 2 , Animais , Pressão Sanguínea , Modelos Animais de Doenças , Antagonistas de Aminoácidos Excitatórios/administração & dosagem , Técnicas de Transferência de Genes , Vetores Genéticos , Proteínas de Fluorescência Verde/biossíntese , Proteínas de Fluorescência Verde/genética , Frequência Cardíaca , Humanos , Hipertensão/enzimologia , Hipertensão/genética , Hipertensão/fisiopatologia , Injeções , Ácido Cinurênico/administração & dosagem , Lentivirus/genética , Masculino , Bulbo/efeitos dos fármacos , Bulbo/fisiopatologia , Norepinefrina/urina , Peptidil Dipeptidase A/genética , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Receptores de Glutamato/efeitos dos fármacos , Receptores de Glutamato/metabolismo , Fatores de Tempo , Regulação para Cima
7.
ScientificWorldJournal ; 2014: 743254, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24678276

RESUMO

We employ the complex method to obtain all meromorphic exact solutions of complex (2+1)-dimensional Boiti-Leon-Pempinelli equations (BLP system of equations). The idea introduced in this paper can be applied to other nonlinear evolution equations. Our results show that all rational and simply periodic traveling wave exact solutions of the equations (BLP) are solitary wave solutions, the complex method is simpler than other methods, and there exist some rational solutions ur,2 (z) and simply periodic solutions us,2-6(z) which are not only new but also not degenerated successively by the elliptic function solutions. We believe that this method should play an important role for finding exact solutions in the mathematical physics. For these new traveling wave solutions, we give some computer simulations to illustrate our main results.


Assuntos
Modelos Teóricos , Algoritmos
8.
Sheng Li Ke Xue Jin Zhan ; 44(3): 164-8, 2013 Jun.
Artigo em Zh | MEDLINE | ID: mdl-24027821

RESUMO

Salusins are newly discovered cardiovascular active peptides, including salusin-alpha and salusin-beta, which are peptides containing 28 and 20 amino acids respectively. Salusins are widely distributed in tissuse and organs of human and rat, and have a series of cardiovascular effects, including lowering blood pressure, slowing down the heart rate, inhibiting myocardial contraction, reducing cardiac ischemic injury, and promoting hypertrophy of cardiomyocytes and proliferation of vascular smooth muscle cells. It is noteworthy to mention that salusin-alpha and salusin-beta are polypeptides produced by the same precursor and play opposite roles in the development and progression of atherosclerosis.


Assuntos
Aterosclerose/fisiopatologia , Sistema Cardiovascular/fisiopatologia , Peptídeos e Proteínas de Sinalização Intercelular/fisiologia , Animais , Pressão Sanguínea/fisiologia , Frequência Cardíaca/fisiologia , Humanos , Contração Miocárdica/fisiologia
9.
Apoptosis ; 17(4): 410-23, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22119805

RESUMO

MicroRNAs (miRNAs) are a novel class of powerful, endogenous regulators of gene expression. In an intact rat model of myocardial ischemia caused by coronary artery ligation, this study identified 17 miRNAs that changed more than 1.5-fold in the myocardium subjected to 4-h ischemia. Using miRNA microarray analysis, most of these aberrantly expressed miRNAs were confirmed by quantitative RT-PCR. MiR-378, a significantly down-regulated miRNA, was selected for further function study. In serum deprived rat H9c2 cardiomyocytes exposed to hypoxia (1% O(2)), miR-378 expression was down-regulated as well. The overexpression of miR-378 resulting from miR-378 mimic transfection significantly enhanced cell viability, reduced lactate dehydrogenase release, and inhibited apoptosis and necrosis. By contrast, miR-378 deficiency resulting from miR-378 inhibitor transfection aggravated the hypoxia-induced apoptosis and cell injury. In accordance, miR-378 inhibitor caused significant apoptosis and cell injury to cardiomyocytes cultured under normoxia. Using bioinformatic algorithms, caspase-3, a key apoptosis executioner, was predicted as a putative target of miR-378. The quantitative RT-PCR showed no effects of miR-378 mimic or inhibitor on caspase-3 mRNA level. However, the amount of caspase-3 proteins was reduced by miR-378 mimic, whereas increased by miR-378 inhibitor. Furthermore, the luciferase reporter assay confirmed caspase-3 to be a target of miR-378, and the apoptosis and cell injury caused by miR-378 inhibitor in both normoxic and hypoxic cells were abolished by a caspase-3 inhibitor. This study first showed that miR-378 inhibited caspase-3 expression and attenuated ischemic injury in cardiomyocytes. It may represent a potential novel treatment for apoptosis and ischemic heart disease.


Assuntos
Apoptose , Caspase 3/genética , Regulação para Baixo , MicroRNAs/genética , Isquemia Miocárdica/genética , Miócitos Cardíacos/citologia , Miócitos Cardíacos/enzimologia , Animais , Caspase 3/metabolismo , Células Cultivadas , Masculino , MicroRNAs/metabolismo , Isquemia Miocárdica/enzimologia , Isquemia Miocárdica/metabolismo , Isquemia Miocárdica/fisiopatologia , Miócitos Cardíacos/metabolismo , Ratos , Ratos Sprague-Dawley
10.
J Cell Sci ; 123(Pt 14): 2444-52, 2010 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-20571053

RESUMO

MicroRNAs are involved in several aspects of cardiac hypertrophy, including cardiac growth, conduction, and fibrosis. However, their effects on the regulation of the cardiomyocyte cytoskeleton in this pathological process are not known. Here, with microRNA microarray and small RNA library sequencing, we show that microRNA-1 (miR-1) is the most abundant microRNA in the human heart. By applying bioinformatic target prediction, a cytoskeleton regulatory protein twinfilin-1 was identified as a potential target of miR-1. Overexpression of miR-1 not only reduced the luciferase activity of the reporter containing the 3' untranslated region of twinfilin-1 mRNA, but also suppressed the endogenous protein expression of twinfilin-1, indicating that twinfilin-1 is a direct target of miR-1. miR-1 was substantially downregulated in the rat hypertrophic left ventricle and phenylephrine-induced hypertrophic cardiomyocytes, and accordingly, the protein level of twinfilin-1 was increased. Furthermore, overexpression of miR-1 in hypertrophic cardiomyocytes reduced the cell size and attenuated the expression of hypertrophic markers, whereas silencing of miR-1 in cardiomyocytes resulted in the hypertrophic phenotype. In accordance, twinfilin-1 overexpression promoted cardiomyocyte hypertrophy. Taken together, our results demonstrate that the cytoskeleton regulatory protein twinfilin-1 is a novel target of miR-1, and that reduction of miR-1 by hypertrophic stimuli induces the upregulation of twinfilin-1, which in turn evokes hypertrophy through the regulation of cardiac cytoskeleton.


Assuntos
Cardiomegalia/metabolismo , Citoesqueleto/metabolismo , MicroRNAs/metabolismo , Proteínas dos Microfilamentos/metabolismo , Miócitos Cardíacos/metabolismo , Proteínas Tirosina Quinases/metabolismo , Animais , Animais Recém-Nascidos , Cardiomegalia/induzido quimicamente , Cardiomegalia/genética , Biologia Computacional , Perfilação da Expressão Gênica , Humanos , Camundongos , MicroRNAs/genética , Análise em Microsséries , Proteínas dos Microfilamentos/genética , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/imunologia , Miócitos Cardíacos/patologia , Células NIH 3T3 , Fenilefrina/farmacologia , Ligação Proteica/efeitos dos fármacos , Proteínas Tirosina Quinases/genética , Ratos , Ratos Sprague-Dawley , Transgenes/genética
11.
J Physiol ; 589(Pt 21): 5153-65, 2011 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-21930604

RESUMO

Although both diabetes and hypertension are risk factors for cardiovascular disease, the role of hyperglycaemia per se in endothelial dysfunction is controversial. This study was designed to examine whether hyperglycaemia, or streptozotocin-induced diabetes, could aggravate endothelial dysfunction in stroke-prone spontaneously hypertensive rats (SHRSP). Hyperglycaemia was induced by streptozotocin in 2-month-old SHRSP and age-matched normotensive Wistar-Kyoto (WKY) rats. The aorta was isolated 8 weeks after induction of hyperglycaemia to record its function and to examine its morphology with transmission electron microscopy. Endothelial/inducible nitric oxide synthase (eNOS/iNOS) and inducible/constitutive haem oxygenase (HO-1/HO-2) levels were determined with Western blotting. Aortic endothelial function and production of reactive oxygen species and nitric oxide were assayed after incubation in vitro in hyperglycaemic, hyperosmolar solution. Streptozotocin-induced diabetes of 8 weeks duration did not result in endothelial dysfunction in normotensive WKY rats. In contrast, hyperglycaemic WKY rats showed significantly enhanced endothelium-dependent vasodilatation, which was abrogated by simultaneous blocking of NOS and HO. The enhanced vasodilatation was associated with elevation of vascular eNOS and HO-1. Significant endothelial dysfunction and massive macrophage-monocyte infiltration were found in SHRSP aorta (the ratio of the number of macrophages to endothelial cells in the intima, expressed as a percentage, was 20.9 ± 2.8% in SHRSP versus 1.9 ± 0.5% in WKY rats, P < 0.01), which was attenuated significantly in hyperglycaemic SHRSP (11.3 ± 1.6%, P < 0.01 versus SHRSP). Acute hyperglycaemia (10 min) aggravated endothelial dysfunction in SHRSP, with a marked increase in intracellular reactive oxygen species and NO production. Sustained in vitro incubation in hyperglycaemic/hyperosmolar conditions (addition of an extra 50 mmol L(-1) of glucose or mannitol to the usual buffer, to produce a final osmolarity of 350 mosmol L(-1)) for 5 h enhanced endothelium-dependent vasodilatation, with elevated vessel NO production and upregulation of eNOS/HO-1 proteins. Sustained hyperglycaemia does not aggravate endothelial dysfunction and macrophage infiltration in SHRSP. Hyperglycaemia/hyperosmolarity-induced upregulation of eNOS and HO-1 may play a role in this paradoxical adaptation of endothelial function.


Assuntos
Aorta Torácica/fisiopatologia , Diabetes Mellitus Experimental/fisiopatologia , Hiperglicemia/fisiopatologia , Hipertensão/fisiopatologia , Vasodilatação , Acetilcolina/farmacologia , Animais , Anti-Hipertensivos/farmacologia , Aorta Torácica/metabolismo , Aorta Torácica/ultraestrutura , Diabetes Mellitus Experimental/metabolismo , Heme Oxigenase (Desciclizante)/metabolismo , Hiperglicemia/induzido quimicamente , Hiperglicemia/metabolismo , Hipertensão/metabolismo , Técnicas In Vitro , Macrófagos/fisiologia , Macrófagos/ultraestrutura , Masculino , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/metabolismo , Nitroprussiato/farmacologia , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Espécies Reativas de Oxigênio/metabolismo , Estreptozocina , Túnica Íntima/patologia , Túnica Íntima/ultraestrutura , Vasodilatação/efeitos dos fármacos , Vasodilatadores/farmacologia
12.
Yi Chuan ; 33(5): 437-42, 2011 May.
Artigo em Zh | MEDLINE | ID: mdl-21586390

RESUMO

The biosecurity of transgenic organism has been widely concerned and extremely restricted its application. Recently, many technological strategies have been developed to ensure its biosecurity. Thus, transgene containment technologies have become one of the hotspots in current transgenic research. In this paper, several transgene containment technologies, such as marker-free transgenic technology, safety marker transgenic technology, chloroplast transgenic technologies, terminator technology, male sterility technology, and 'GM-gene-deletor'technology were reviewed and evaluated. 'GM-gene-deletor' technology, as one of these technologies, demonstrated a prosperous future for safe application of transgenic organisms. Finally, the strategies for developing new transgene containment technologies have been suggested.


Assuntos
Técnicas de Transferência de Genes , Organismos Geneticamente Modificados , Transgenes , Cloroplastos/genética
13.
J Cell Physiol ; 225(2): 437-43, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20458739

RESUMO

Cardiac hypertrophy, which is characterized by an increase in cell size and reactivation of fetal genes, occurs as an adaptive response to diverse forms of stress and often results in heart failure and sudden death. Growing evidence indicates that microRNAs (miRNAs) are involved in cardiac hypertrophy, but the function of these miRNAs remains elusive. Here, using real time PCR analysis, we showed that several miRNAs were dynamically regulated in the rat hypertrophic hearts and miR-199a was up-regulated by 10-fold in hypertrophic hearts after abdominal aorta constriction for 12 weeks. With tissue profiling analysis, we showed that miR-199a was predominantly expressed in cardiomyocytes, but was also faintly detected in cardiac fibroblasts. To investigate whether miR-199a was involved in cardiac hypertrophy, both over-expression and knockdown of miR-199a were performed in cultured cardiomyocytes. Over-expression of miR-199a in cardiomyocytes increased the cell size as measured by cell surface area, and also reduced the mRNA expression level of alpha-myosin heavy chain. In accordance, knockdown of endogenous miR-199a in cardiomyocytes reduced the cell size. Down-regulation of miR-199a also attenuated the phenylephrine-induced increase of cell size. Furthermore, bioinformatic algorithms were used to predict the potential targets of miR-199a in cardiac hypertrophy, and hypoxia-inducible factor 1 alpha was confirmed by the luciferase reporter assay to be a potential target of miR-199a. Taken together, our results demonstrated that miR-199a, which was predominantly expressed in cardiomyocytes, was essential for the maintenance of cell size of cardiomyocytes and might play a role in the regulation of cardiac hypertrophy.


Assuntos
Cardiomegalia/metabolismo , Tamanho Celular , MicroRNAs/metabolismo , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Agonistas alfa-Adrenérgicos/farmacologia , Animais , Regulação para Baixo , Deleção de Genes , Humanos , Masculino , MicroRNAs/genética , Miócitos Cardíacos/efeitos dos fármacos , Fenilefrina/farmacologia , Ratos , Ratos Sprague-Dawley , Regulação para Cima
14.
Clin Exp Pharmacol Physiol ; 37(10): 955-62, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20557321

RESUMO

1. Leptin, an important adipose-derived hormone, can be associated with cardiac pathophysiology; however, the role of leptin in cardiomyocyte apoptosis is poorly understood. The present study examines serum-deprivation-induced apoptosis in primary cultured cardiomyocytes treated with leptin. 2. Cardiomyocytes were subjected to serum deprivation in the presence or absence of leptin (5 or 50 nmol/L) for 48 h. Apoptosis was determined by Hoechst 33258 and Annexin V-FITC/propidium iodide dual staining. Cell viability, malondialdehyde (MDA) content, caspase 3 activation, and the expression and enzyme activity of superoxide dismutase (SOD) were measured. Small interference RNA (siRNA) targeting SOD1 and SOD2 were used to knockdown their expression and measure apoptosis. 3. Serum deprivation caused nearly 30% of apoptosis in cardiomyocytes, and an approximately 60% decrease in cell viability. The mRNA levels and the activated form of caspase 3 were greatly increased. In the presence of leptin, the apoptotic rate was reduced to approximately 15%, cell viability was increased and the activation of caspase 3 was partially inhibited. Additionally, the augmented lipid peroxidation (MDA formation) was abolished, and the impaired activities of SOD1 and SOD2 were restored by leptin. The mRNA expression of SOD2, but not SOD1, was stimulated by leptin. Transfection with siRNA that cause deficiency of either SOD1 or SOD2 attenuated the anti-apoptotic effects of leptin. 4. The results suggest that leptin inhibits serum-deprivation-induced apoptosis in cardiomyocytes by activating SOD. The present study outlines the direct actions of leptin in cardiac disorders that are related to elevated leptin levels.


Assuntos
Antioxidantes/metabolismo , Apoptose/fisiologia , Citoproteção/fisiologia , Leptina/fisiologia , Miócitos Cardíacos/metabolismo , Animais , Animais Recém-Nascidos , Apoptose/efeitos dos fármacos , Caspase 3/biossíntese , Inibidores de Caspase , Células Cultivadas , Meios de Cultura Livres de Soro , Citoproteção/efeitos dos fármacos , Miócitos Cardíacos/patologia , Ratos , Ratos Sprague-Dawley
15.
Peptides ; 30(2): 439-44, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18992781

RESUMO

The high prevalence of obesity and diabetes will lead to higher rates of morbidity and mortality. It is well known that ghrelin plays a potential role in obesity and diabetes. Obestatin, a novel 23 amino acid amidated peptide encoded by the same gene that encodes ghrelin, was initially reported to have opposite actions to ghrelin in the regulation of food intake, emptying of the stomach and body weight. Recent work suggests that obestatin also regulate beta-cell survival and insulin secretion. The ghrelin-obestatin system is, therefore, a promising target for the developing of new drugs for the treatment of obesity and diabetes. This review summarizes the interrelationship between obestatin, obesity and diabetes.


Assuntos
Diabetes Mellitus/etiologia , Grelina/fisiologia , Obesidade/etiologia , Animais , Diabetes Mellitus/metabolismo , Ingestão de Alimentos , Grelina/metabolismo , Humanos , Células Secretoras de Insulina/metabolismo , Obesidade/metabolismo
16.
Acta Pharmacol Sin ; 30(12): 1594-600, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19960005

RESUMO

AIM: To determine the effects of the centrally antihypertensive drug moxonidine injected into the rostral ventrolateral medulla (RVLM) on baroreflex function in spontaneously hypertensive rats (SHR). METHODS: Baroreflex sensitivity control of renal sympathetic nerve activity (RSNA) and barosensitivity of the RVLM presympathetic neurons were determined following application of different doses of moxonidine within the RVLM. RESULTS: Three doses (0.05, 0.5, and 5 nmol in 50 nL) of moxonidine injected bilaterally into the RVLM dose-dependently reduced the baseline blood pressure (BP) and RSNA in SHR. At the highest dose (5 nmol) of moxonidine injection, the maximum gain (1.24%+/-0.04%/mmHg) of baroreflex control of RSNA was significantly decreased. However, the lower doses (0.05 and 0.5 nmol) of moxonidine injection into the RVLM significantly enhanced the baroreflex gain (2.34%+/-0.08% and 2.01%+/-0.07%/mmHg). The moxonidine-induced enhancement in baroreflex function was completely prevented by the imidazoline receptor antagonist efaroxan but not by the alpha(2)-adrenoceptor antagonist yohimbine. A total of 48 presympathetic neurons were recorded extracellularly in the RVLM of SHR. Iontophoresis of applied moxonidine (30-60 nA) dose-dependently decreased the discharge of RVLM presympathetic neurons but also significantly increased the barosensitivity of RVLM presympathetic neurons. CONCLUSION: These data demonstrate that a low dose of moxonidine within the RVLM has a beneficial effect on improving the baroreflex function in SHR via an imidazoline receptor-dependent mechanism.


Assuntos
Antagonistas Adrenérgicos alfa/farmacologia , Anti-Hipertensivos/farmacologia , Barorreflexo/efeitos dos fármacos , Benzofuranos/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Imidazóis/farmacologia , Receptores de Imidazolinas/metabolismo , Bulbo/fisiologia , Neurônios/efeitos dos fármacos , Sistema Nervoso Simpático/efeitos dos fármacos , Potenciais Sinápticos/efeitos dos fármacos , Ioimbina/farmacologia , Animais , Barorreflexo/fisiologia , Pressão Sanguínea/fisiologia , Relação Dose-Resposta a Droga , Receptores de Imidazolinas/antagonistas & inibidores , Iontoforese , Rim/inervação , Rim/fisiologia , Bulbo/citologia , Microinjeções , Neurônios/fisiologia , Ratos , Ratos Endogâmicos SHR , Sistema Nervoso Simpático/fisiologia , Potenciais Sinápticos/fisiologia
17.
Biochem Biophys Res Commun ; 369(3): 969-72, 2008 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-18329381

RESUMO

Obestatin is a bioactive peptide encoded by the same gene that encodes ghrelin. Our aim was to investigate the effect of obestatin on insulin secretion. We evaluated the effects of obestatin on insulin secretion from rat islet cells which had been incubated overnight in the presence of 8.3, 11.1, and 22.2 mmol/l of glucose. In vivo, the serum levels of glucose and insulin were measured 0, 1, 5, 10, 20, 40, and 60 min after the intravenous administration of saline or glucose (1g/kg), with or without obestatin, and the area under the 60 min curve of insulin concentration (AUC(insulin)) was calculated. Obestatin (0.01-100 nmol/l) inhibited insulin secretion from rat islets in a dose-dependent fashion. In vivo, when administered intravenously to rats together with glucose, obestatin (10, 50, and 250 nmol/kg) inhibited both the rapid 1-min insulin response and the AUC(insulin) in a dose-dependent fashion. Our data demonstrate that under glucose-stimulated conditions, exogenous obestatin acts as a potent inhibitor of insulin secretion in anaesthetized rats in vivo as well as in cultured islets in vitro.


Assuntos
Grelina/farmacologia , Glucose/antagonistas & inibidores , Antagonistas da Insulina/farmacologia , Insulina/metabolismo , Ilhotas Pancreáticas/efeitos dos fármacos , Animais , Glicemia/efeitos dos fármacos , Relação Dose-Resposta a Droga , Grelina/administração & dosagem , Glucose/farmacologia , Injeções Intravenosas , Insulina/sangue , Secreção de Insulina , Ilhotas Pancreáticas/metabolismo , Masculino , Ratos , Ratos Sprague-Dawley
18.
Peptides ; 29(7): 1247-54, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18400333

RESUMO

Obestatin, a sibling of ghrelin derived from preproghrelin, opposes several physiological actions of ghrelin. Our previous study has demonstrated that both plasma ghrelin and obestatin levels were decreased significantly 2h after food intake in human. To further expand current knowledge, we investigated the temporal profiles of their levels in ad libitum fed rats, 48h fasted rats and 48h fasted rats refed 2h with a standard chow, crude fiber, 50% glucose or water, and their expressions in stomach, liver and pancreatic islets immunohistochemically. Plasma ghrelin and obestatin levels were measured by EIA. Plasma leptin, insulin and glucose levels were also evaluated. Both plasma ghrelin and obestatin levels increased significantly in fasted rats compared with ad libitum fed rats. The ingestion of standard chow produced a profound and sustained suppression of ghrelin levels, whereas plasma obestatin levels decreased significantly but recovered quickly. Intake of crude fiber or 50% glucose, however, produced a more profound and sustained suppression of obestatin levels, though they had relatively less impact on ghrelin levels. Plasma glucose was the only independent predictor of ghrelin levels, obestatin levels, and ghrelin to obestatin ratios. Obestatin immunoreactivity was detected in the fundus of stomach, liver and pancreatic islets, with roughly similar patterns of distribution to ghrelin. These data show quantitative and qualitative differences in circulating ghrelin and obestatin responses to the short-term feeding status and nutrient composition, and may support a role for obestatin in regulating metabolism and energy homeostasis.


Assuntos
Ração Animal/análise , Ingestão de Alimentos/efeitos dos fármacos , Jejum , Grelina/farmacologia , Animais , Grelina/sangue , Grelina/fisiologia , Imuno-Histoquímica , Masculino , Ratos , Ratos Sprague-Dawley
19.
Life Sci ; 83(17-18): 620-4, 2008 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-18805429

RESUMO

AIMS: Corticotropin-releasing hormone (CRH) has been implicated in the mechanisms controlling human parturition. The aims of the present study were to explore effects of CRH on contractility of human term myometrium and compare these effects in labouring and non-labouring myometrial strips. MAIN METHODS: The cumulative effects of CRH (10(-10) to 10(-7) mol/l) on the spontaneous contractility of labouring and non-labouring myometrial samples were evaluated using isometric tension recordings. KEY FINDINGS: CRH exhibited a concentration-dependent relaxant effect on spontaneous contractions in non-labouring term myometrium. This effect was mediated principally via a reduction in the amplitude rather than any changes in the frequency of contractions. The CRH-induced inhibitory effect on contractility could be blocked by pre-treatment with a CRH-R1 antagonist antalarmin, but not by pre-treatment with the CRH-R2 antagonist astressin 2B. CRH had no effect on spontaneous contractions in the labouring myometrium, as no change in either the amplitude or the frequency was observed. SIGNIFICANCE: Our findings indicate that CRH acts on CRH-R1 to inhibit spontaneous contractions in term myometrium from women who were not undergoing labour, but not those who were undergoing labour, supporting the hypothesis that CRH exerts dual effect on myometrium during pregnancy.


Assuntos
Hormônio Liberador da Corticotropina/farmacologia , Miométrio/efeitos dos fármacos , Gravidez/fisiologia , Receptores de Hormônio Liberador da Corticotropina/efeitos dos fármacos , Contração Uterina/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Humanos , Técnicas In Vitro , Miométrio/fisiologia , Receptores de Hormônio Liberador da Corticotropina/fisiologia
20.
Sci Rep ; 8(1): 4660, 2018 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-29549288

RESUMO

Shenfu Injection (SFI) is a classical Chinese medicine used to treat heart failure. Our previous study demonstrated that miRNAs underwent changes in rats with myocardial hypertrophy induced by abdominal aortic constriction. Interestingly, there was a significant change in miR-19a-3p, whose target gene is known to be associated with MEF2 signaling. However, whether and how SFI regulates miR-19a-3p in the treatment of myocardial hypertrophy has not been investigated. The purpose of the present study was to investigate the regulatory effect of SFI on miR-19a-3p in MEF2 signaling in the rat hypertrophic myocardium. We found that the miR-19a-3p expression level was significantly decreased in the hypertrophic myocardium, and MEF2A was the target gene of miR-19a-3p. The protein expressions of MEF2A, ß-MHC, BNP and TRPC1 were significantly increased in hypertrophic cardiomyocytes. MiR-19a-3p was up-regulated after SFI treatment, and the protein expressions of these genes were significantly decreased. In addition, miR-19a-3p over-expression in hypertrophic cardiomyocytes could decrease MEF2A mRNA and protein expressions, and anti-miR-19a-3p showed the opposite result. Our study provided substantial evidence that miR-19a-3p played a functional role in MEF2 signaling in myocardial hypertrophy. SFI attenuated cardiomyocyte hypertrophy probably through up-regulating or maintaining the miR-19a-3p levels and regulating the MEF2 signaling pathway.


Assuntos
Cardiomegalia/tratamento farmacológico , Medicamentos de Ervas Chinesas/administração & dosagem , MicroRNAs/genética , Regulação para Cima , Regiões 3' não Traduzidas , Animais , Cardiomegalia/genética , Cardiomegalia/metabolismo , Células Cultivadas , Modelos Animais de Doenças , Medicamentos de Ervas Chinesas/farmacologia , Perfilação da Expressão Gênica/métodos , Regulação da Expressão Gênica/efeitos dos fármacos , Injeções , Fatores de Transcrição MEF2/genética , Fatores de Transcrição MEF2/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos/métodos , Ratos , Transdução de Sinais
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