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1.
Int Heart J ; 60(5): 1168-1175, 2019 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-31484876

RESUMO

The aims of the present study were to investigate the effects of angiotensin receptor neprilysin inhibitors (ARNi) on the susceptibility of ventricular arrhythmias (VAs) in rats with myocardial infarction (MI) and to explore the related mechanisms.A total of 32 adult male Sprague-Dawley rats were divided into 3 groups: a control group, MI group, and MI+ARNi group. MI was generated by ligation of the left anterior descending coronary artery. ARNi was given at 68 mg/kg/day for 4 weeks after MI surgery. At 4 weeks after MI, electrical programmed stimulation (EPS) was performed in all groups for the evaluation of VAs, and echocardiography was used to evaluate cardiac function. Indicators of sympathetic neural remodeling and cardiac remodeling were detected to further explore the related mechanisms.Four weeks after MI, rats in the ARNi group exhibited low susceptibility of VAs in comparison with that in the MI group, which was coincident with the attenuation of sympathetic nerve remodeling, amelioration of cardiac fibrosis, and regulation of Cx43 expression.ARNi is effective in reducing VAs in rats with ischemic cardiomyopathy, which is associated with attenuating sympathetic nerve remodeling and myocardial fibrosis.


Assuntos
Conexina 43/metabolismo , Infarto do Miocárdio/tratamento farmacológico , Neprilisina/farmacologia , Taquicardia Ventricular/tratamento farmacológico , Remodelação Ventricular/efeitos dos fármacos , Animais , Biópsia por Agulha , China , Modelos Animais de Doenças , Ecocardiografia/métodos , Imuno-Histoquímica , Masculino , Contração Miocárdica/efeitos dos fármacos , Infarto do Miocárdio/diagnóstico por imagem , Infarto do Miocárdio/patologia , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Fatores de Risco , Taxa de Sobrevida , Sistema Nervoso Simpático/efeitos dos fármacos , Taquicardia Ventricular/diagnóstico por imagem
2.
Biomater Sci ; 7(9): 3906-3917, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31322163

RESUMO

Cardiovascular diseases represent a major socio-economic burden. In recent years, considerable effort has been invested in optimizing cell delivery strategies to advance cell transplantation therapies to restore heart function for example after an infarct. A particular issue is that the implantation of cells using a non-electroconductive matrix potentially causes arrhythmia. Here, we demonstrate that our hydrazide-functionalized nanotubes-pericardial matrix-derived electroconductive biohybrid hydrogel provides a suitable environment for maturation of human-induced pluripotent stem cell (hiPSC)-derived cardiomyocytes. hiPSC-derived cardiomyocytes exhibited an improved contraction amplitude (>500%) on conductive hydrogels compared to cells cultured on Matrigel®. This was accompanied by increased cellular alignment, enhanced connexin 43 expression, and improved sarcomere organization suggesting maturation of the hiPSC-derived cardiomyocytes. Sarcomeric length of these cells increased from 1.3 to 1.7 µm. Moreover, 3D cell-laden engineered tissues exhibited enhanced calcium handling as well as positive response to external electrical and pharmaceutical stimulation. Collectively, our data indicate that our biohybrid hydrogels consisting of solubilized nanostructured pericardial matrix and electroconductive positively charged hydrazide-conjugated carbon nanotubes provide a promising material for stem cell-based cardiac tissue engineering.


Assuntos
Materiais Biocompatíveis/química , Hidrogéis/química , Células-Tronco Pluripotentes Induzidas/citologia , Miócitos Cardíacos/citologia , Nanotubos de Carbono/química , Pericárdio/química , Tecidos Suporte/química , Biomarcadores/metabolismo , Cálcio/metabolismo , Diferenciação Celular , Proliferação de Células , Sobrevivência Celular , Colágeno/química , Conexina 43/metabolismo , Combinação de Medicamentos , Condutividade Elétrica , Humanos , Laminina/química , Células-Tronco Mesenquimais/citologia , Tamanho da Partícula , Proteoglicanas/química
3.
Neoplasma ; 20192019 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-31307202

RESUMO

The aim of study was to identify the downstream target genes of CX43 by Human Transcriptome Array. Therefore, a gene microarray was generated which consists of CX43-overexpressed hepatocellular carcinoma (HCC) cells transfected with the constructed plasmid and negative controls to identify candidate genes. Integrated bioinformatic analysis was used to clarify biological functions of the identified genes, including Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway, protein-protein interaction network, and survival analysis. The candidate genes were further validated by qRT-PCR in liver cancer tissues and CX43-silenced HCC cells. We have found the mRNA and protein levels of CX43 significantly upregulated in HCC cells transfected with CX43 constructed plasmid. We identified 928 differentially expressed genes including 394 upregulated and 534 downregulated genes, enriched in the cancer related functions and pathways by GO and KEGG pathway analysis. The protein-protein interaction network revealed 9 hub genes in this study. Statistical analysis indicated that upregulation of RALA and SRC was associated with poor prognosis in liver cancer. The differential expression of 2 candidate genes were further validated in HCC cells and tissues. In conclusion, protein-coding genes RALA and SRC could be target genes of CX43 and therapeutic targets for hepatocellular carcinoma.


Assuntos
Carcinoma Hepatocelular , Conexina 43 , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/fisiopatologia , Conexina 43/genética , Conexina 43/metabolismo , Perfilação da Expressão Gênica , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/fisiopatologia
4.
Life Sci ; 232: 116624, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31276689

RESUMO

AIMS: Monocyte-endothelial adhesion is considered to be the primary initiator of inflammatory vascular diseases, such as atherosclerosis. Connexin 43 (Cx43) has been reported to play an important part in this process, however, the underlying mechanisms are not fully understood. Intravenous anesthetics, propofol is commonly used in the perioperative period and in the intensive care unit, and considered to have good anti-inflammatory and antioxidant effects. Thus, we speculate that propofol could influence monocyte-endothelial adhesion, and explore whether its possible mechanism is relative with Cx43 expression in U937 monocytes influencing cell adhesion of U937 monocytes to human umbilical vein endothelial cells (HUVEC). MAIN METHODS: Cx43-siRNAs or pc-DNA-Cx43 were used to alter Cx43 expression in U937 monocytes. Propofol was given as pretreatments to U937 monocytes. Then, cell adhesion, ZO-1, LFA-1, VLA-4, COX and MCP-1 were determined. PI3K/AKT/NF-κB signaling pathway was explored to clarify the possible mechanism. KEY FINDINGS: Alternation of Cx43 expression affects cell adhesion and adhesion molecules significantly, such as ZO-1, LFA-1, VLA-4, COX-2 and MCP-1, the mechanism of which is relative with Cx43 influencing the activation of PI3K/AKT/NF-κB signaling pathway. Preconditioning with propofol at its clinically relevant anesthesia concentration attenuates cell adhesion. Propofol not only decreases Cx43 expression in U937 monocytes, but also depresses the activation of PI3K/AKT/NF-κB signaling pathway. SIGNIFICANCE: Modulation Cx43 expression in U937 monocytes could affect cell adhesion via regulating the activation of PI3K/AKT/NF-κB signaling pathway. Propofol attenuates cell adhesion via inhibiting Cx43 and its downstream signaling pathway of PI3K/AKT/NF-κB.


Assuntos
Adesão Celular/efeitos dos fármacos , Monócitos/efeitos dos fármacos , Propofol/farmacologia , Aterosclerose/metabolismo , Moléculas de Adesão Celular/metabolismo , Conexina 43/efeitos dos fármacos , Conexina 43/genética , Conexina 43/metabolismo , Endotélio Vascular/metabolismo , Expressão Gênica/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Molécula 1 de Adesão Intercelular/metabolismo , Monócitos/fisiologia , NF-kappa B/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Propofol/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Células U937/metabolismo , Molécula 1 de Adesão de Célula Vascular/metabolismo
5.
J Food Sci ; 84(7): 1703-1711, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31218711

RESUMO

We evaluated the effect of krill oil (KO) supplement on seizures induced by pentylenetetrazole (PTZ) in animals with previous febrile seizures (FSs) induced by hyperthermia to determine its effectiveness in seizure susceptibility and as an anticonvulsant. Male Wistar rats with FS separated into water (W, 1 mL), palm oil (PO, 300 mg/kg, total volume 1 mL), or KO (300 mg/kg, total volume 1 mL) groups. All drugs were administered chronically via the intragastric route. Electrical activity was recorded by intracranial EEG simultaneously with convulsive behavior. All animals' brains were processed by immunofluorescence against GFAP, NeuN, and connexins (Cx); cellular quantification was performed in hippocampus and pyramidal or granular layer thickness was evaluated with cresyl violet (CV) staining. The results showed a significant delay in convulsive behavior and a slight increased survival time after PTZ administration in the group treated with KO compared with PO and W groups. The epileptiform activity showed high amplitude and frequency, with no significant differences between groups, nor were there differences in the number and duration of discharge trains. KO and PO increased the number of astrocytes and the number of neurons compared with the W group. KO and PO decreased the expression of Cx36 without affecting Cx43 expression or the thickness of layers. Based on these data, we consider it important to perform more experiments to determine the anticonvulsant role of KO, taking into account the partial effect found in this study. KO could be used as a coadjuvant of traditional anticonvulsive treatments. PRACTICAL APPLICATION: In this study was evaluated the anticonvulsive effect of a chronic krill oil (KO) supplement in animals with seizures. Results showed that KO had partial anticonvulsive effects measured by EEG activity and convulsive behavior analysis. These data justify further research that looks at KO supplementation as a prospective coadjuvant of pharmacologic management of seizure disorder.


Assuntos
Anticonvulsivantes/administração & dosagem , Euphausiacea/química , Hipocampo/efeitos dos fármacos , Óleos Vegetais/administração & dosagem , Convulsões Febris/tratamento farmacológico , Animais , Conexina 43/genética , Conexina 43/metabolismo , Conexinas/genética , Conexinas/metabolismo , Suplementos Nutricionais/análise , Proteína Glial Fibrilar Ácida/genética , Proteína Glial Fibrilar Ácida/metabolismo , Hipocampo/metabolismo , Humanos , Masculino , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Pentilenotetrazol/efeitos adversos , Ratos , Ratos Wistar , Convulsões Febris/induzido quimicamente , Convulsões Febris/genética , Convulsões Febris/metabolismo
6.
Sheng Li Xue Bao ; 71(3): 395-404, 2019 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-31218330

RESUMO

The present study was designed to examine whether Ramipril (an inhibitor of angiotensin-converting enzyme) affected spontaneous hypertension-induced injury of cerebral artery by regulating connexin 43 (Cx43) expression. Wistar-Kyoto (WKY) and spontaneously hypertensive rats (SHR) were randomly divided into WKY, WKY + Ramipril, SHR, and SHR + Ramipril groups (n = 8). The arterial pressure was monitored by the tail-cuff method, and vascular function in basilar arteries was examined by pressure myography. Hematoxylin-eosin (HE) staining was used to show vascular remodeling. The expression and distribution of Cx43 was determined by using immunofluorescence and immunohistochemistry analysis. The protein and mRNA levels of Cx43 were examined by Western blot and real-time PCR analysis, respectively. The results showed that chronic Ramipril treatment significantly attenuated blood pressure elevation (P < 0.01, n = 8) and blood vessel wall thickness in SHR (P < 0.01, n = 8). The cerebral artery contraction rate in the SHR group was higher than that in the WKY group (P < 0.05, n = 8). The cerebral artery contraction rate in the SHR + Ramipril group was lower than that in the SHR group (P < 0.05, n = 8). Pretreatment with 2-APB (Cx43 non-specific blocker) or Gap26 (Cx43 specific blocker) significantly decreased the vasoconstriction rate, while pretreatment with AAP10 (Cx43 non-specific agonist) significantly increased the vasoconstriction in the SHR + Ramipril group (P < 0.05, n = 8). In addition, the expression of Cx43 mRNA and protein in cerebral arteries of SHR group was higher than that of WKY group (P < 0.05, n = 8). The mRNA and protein expression of Cx43 in cerebral arteries of SHR + Ramipril group was significantly lower than that of SHR group (P < 0.05, n = 8). These results suggest that Ramipril can down-regulate the expression of Cx43 mRNA and protein in cerebral arterial cells of SHR, lower blood pressure, promote vasodilation, and improve arterial damage and vascular dysfunction caused by hypertension.


Assuntos
Artérias Cerebrais/efeitos dos fármacos , Conexina 43/metabolismo , Ramipril/farmacologia , Remodelação Vascular , Animais , Pressão Sanguínea , Artérias Cerebrais/metabolismo , Hipertensão/tratamento farmacológico , Distribuição Aleatória , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY
7.
Mol Med Rep ; 19(6): 5291-5300, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31059055

RESUMO

Atherosclerosis (AS) is an inflammatory disease that occurs in the arterial wall and is characterized by progressive lipid accumulation within the intima of large arteries, leading to the dysfunction of endothelial cells and further destruction of the endothelial barrier and vascular tone. Arterial intima injury accelerates the adhesion and activation of platelets at the injury site. The activation of platelets results in the secretion of growth factors, leading to the migration and proliferation of vascular smooth muscle cells (VSMCs), promoting the formation of plaque, resulting in the formation of thrombus. The present study found that vorapaxar could alleviate the inflammatory response induced by a high concentration of cholesterol stimulation and increase the release of nitric oxide (NO) via the protein kinase B (AKT) signaling pathway and regulation of the intracellular concentration of Ca2+ ([Ca2+]i). We also found that vorapaxar could reduce the damage of DNA caused by cholesterol stimulation and regulate the cell cycle via the AKT/JNK signaling pathway and its downstream molecules glycogen synthase kinase 3ß (GSK­3ß) and connexin 43, maintaining the integrity of the endothelial barrier and proliferation of endothelial cells, serving a protective role in endothelial cells.


Assuntos
Lactonas/farmacologia , Piridinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Cálcio/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Colesterol/farmacologia , Conexina 43/metabolismo , Citocinas/genética , Citocinas/metabolismo , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , NF-kappa B/metabolismo , Óxido Nítrico/metabolismo , Permeabilidade/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Regulação para Cima/efeitos dos fármacos
8.
Environ Pollut ; 251: 328-337, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31091496

RESUMO

Microcystin-leucine-arginine (MC-LR) can cause male reproductive disorder. However, the underlying mechanism are not yet entirely elucidated. In this study, we aimed to investigated the effects of MC-LR on the integrity of blood-testis barrier (BTB) and the related molecular mechanisms. Both in vivo and in vitro experiments revealed that MC-LR caused disruption of BTB and gap junctions between Sertoli cells respectively, which was paralleled by the alteration of connexin43 (Cx43). Our data demonstrated that MC-LR decreased gap junction intercellular communication (GJIC) and impaired Cx43 expression by activating the phosphatidylinositol 3-kinase/Akt cascades. In addition, a possible protective effect of Icariin (ICA), a flavonoid isolated from Chinese medicinal herb, against MC-LR toxicity was investigated. The ICA prevented the degradation of GJIC and impairment of Cx43 induced by MC-LR via suppressing the Akt pathway. Together, our results confirmed that the expression of Cx43 induced by MC-LR was regulated in vivo and in vitro, which was involved in the destruction of BTB. Additionally, ICA seems to be able to mitigate the MC-LR toxic effects.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Flavonoides/farmacologia , Junções Comunicantes/efeitos dos fármacos , Microcistinas/toxicidade , Proteínas Proto-Oncogênicas c-akt/metabolismo , Células de Sertoli/efeitos dos fármacos , Animais , Peso Corporal/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Conexina 43/metabolismo , Junções Comunicantes/metabolismo , Masculino , Camundongos , Células de Sertoli/metabolismo , Transdução de Sinais/efeitos dos fármacos
9.
Toxicol Lett ; 311: 66-79, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31039416

RESUMO

Decabromodiphenyl ether (BDE-209), a flame retardant, interferes with thyroid homeostasis and androgen biosynthesis. BDE-209 evokes hyperglycemia through impaired glucose homeostasis in rat liver. This study is in continuation to our earlier work for a better understanding of whether or not BDE-209 affects testicular and epididymal physiology in relation to oxidative status in peripupertal mice offspring. Lactating female Parkes mice were orally gavaged with 500 and 700 mg/kg body weight of BDE-209 in corn oil from postnatal day (PND) 1 to PND 28. Male pups of lactating dams were sacrificed at PND 42. Maternal BDE-209 exposure during lactation increased apoptosis and oxidative status with altered expressions of various cell survival (Bcl-2), apoptotic (Bax and caspase-3) and oxidative stress (Nrf2 and HO-1) markers in testes and epididymis of peripubertal mice offspring. Testicular glucose and lactate concentrations were markedly reduced in these pups with down-regulation in GLUT3 and GLUT8 expressions and decreased LDH activity. Maternal BDE-209 exposure markedly affected fertility potential, epididymal histology, sialic acid concentration and sperm quality with decreased expression of epididymal Cx43 and AR in these mice offspring. Results thus suggest that maternal BDE-209 exposure during lactation causes reproductive toxicity in peripubertal mice offspring.


Assuntos
Epididimo/efeitos dos fármacos , Fertilidade/efeitos dos fármacos , Éteres Difenil Halogenados/toxicidade , Infertilidade Masculina/induzido quimicamente , Lactação , Estresse Oxidativo/efeitos dos fármacos , Testículo/efeitos dos fármacos , Fatores Etários , Animais , Conexina 43/metabolismo , Epididimo/metabolismo , Epididimo/patologia , Feminino , Glucose/metabolismo , Heme Oxigenase-1/metabolismo , Homeostase , Infertilidade Masculina/metabolismo , Infertilidade Masculina/patologia , Infertilidade Masculina/fisiopatologia , Masculino , Exposição Materna , Proteínas de Membrana/metabolismo , Camundongos , Fator 2 Relacionado a NF-E2/metabolismo , Gravidez , Receptores Androgênicos/metabolismo , Desenvolvimento Sexual , Transdução de Sinais/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Espermatozoides/metabolismo , Espermatozoides/patologia , Testículo/metabolismo , Testículo/patologia
10.
Am J Chin Med ; 47(3): 657-674, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30974966

RESUMO

Glioblastoma (GBM) is the most commonly occurring tumor in the cerebral hemispheres. Currently, temozolomide (TMZ), an alkylating agent that induces DNA strand breaks, is considered the frontline chemotherapeutic agent for GBM. Despite its frontline status, GBM patients commonly exhibit resistance to TMZ treatment. We have recently established and characterized TMZ-resistant human glioma cells. The aim of this study is to investigate whether curcumin modulates cell apoptosis through the alternation of the connexin 43 (Cx43) protein level in TMZ-resistant GBM. Overexpression of Cx43, but not ATP-binding cassette transporters (ABC transporters), was observed (approximately 2.2-fold) in TMZ-resistant GBM cells compared to the Cx43 levels in parental GBM cells. Furthermore, at a concentration of 10 µ M, curcumin significantly reduced Cx43 protein expression by about 40%. In addition, curcumin did not affect the expression of other connexins like Cx26 or epithelial-to-mesenchymal transition (EMT) proteins such as ß -catenin or α E-catenin. Curcumin treatment led to an increase in TMZ-induced cell apoptosis from 4% to 8%. Importantly, it did not affect the mRNA expression level of Cx43. Concomitant treatment with the translation inhibitor cycloheximide (CHX) exerted additional effects on Cx43 degradation. Treatment with the autophagy inhibitor 3-MA (methyladenine) did not affect the curcumin-induced Cx43 degradation. Interestingly, treatment with the proteasome inhibitor MG132 (carbobenzoxy-Leu-Leu-leucinal) significantly negated the curcumin-induced Cx43 degradation, which suggests that curcumin-induced Cx43 degradation occurs through the ubiquitin-proteasome pathway.


Assuntos
Antineoplásicos Alquilantes/farmacologia , Apoptose/efeitos dos fármacos , Conexina 43/metabolismo , Curcumina/farmacologia , Glioblastoma/genética , Glioblastoma/patologia , Proteólise/efeitos dos fármacos , Temozolomida/farmacologia , Humanos , Estimulação Química , Células Tumorais Cultivadas
11.
Mediators Inflamm ; 2019: 7854389, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30948926

RESUMO

Intestinal injury has long been considered to play a crucial role in the pathophysiology of sepsis and has even been characterized as the "motor" of it. Thus, we explored the effects of connexin43 (Cx43) on sepsis-induced intestinal injury in order to provide potential therapeutic strategies. Rat cecal ligation and puncture (CLP) models in vivo and cell models (IEC-6 cells) pretreated with LPS in vitro were used in the current study. Firstly, different methods, such as Cx43 inhibitors (18-α-GA and oleamide) or siRNA targeting Cx43 and N-acetyl cysteine (NAC) (a kind of ROS scavenger), were used to observe the effects of Cx43 channels mediating ROS transfer on intestinal injury. Secondly, the influence of ROS content on the activity of the JNK1/Sirt1/FoxO3a signaling pathway was explored through the application of NAC, sp600125 (a JNK1 inhibitor), and nicotinamide (a Sirt1 inhibitor). Finally, luciferase assays and ChIP were used to determine the direct regulation of FoxO3a on proapoptotic proteins, Bim and Puma. The results showed that sepsis-induced intestinal injury presented a dynamic change, coincident with the alternation of Cx43 expression. The inhibition of Cx43 attenuated CLP-induced intestinal injury in vivo and LPS-induced IEC-6 injury in vitro. The changes of Cx43 channel function regulated ROS transfer between the neighboring cells, which mediated the activation of the JNK1/Sirt1/FoxO3a signaling pathway. FoxO3a directly affected its downstream target genes, Bim and Puma, which are responsible for cell or tissue apoptosis. In summary, our results suggest that Cx43 inhibition suppresses ROS transfer and inactivates the JNK1/Sirt1/FoxO3a signaling pathway to protect against sepsis-induced intestinal injury.


Assuntos
Conexina 43/metabolismo , Proteína Forkhead Box O3/metabolismo , Intestinos/lesões , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Sepse/complicações , Sirtuína 1/metabolismo , Animais , Conexina 43/antagonistas & inibidores , Conexina 43/genética , Ácido Glicirretínico/análogos & derivados , Ácido Glicirretínico/farmacologia , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Masculino , Ácidos Oleicos/farmacologia , Ratos , Ratos Sprague-Dawley , Sepse/tratamento farmacológico
12.
Biomed Environ Sci ; 32(3): 177-188, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30987692

RESUMO

OBJECTIVE: Pyroptosis is an inflammatory form of programmed cell death. This phenomenon has been recently reported to play an important role in radiation-induced normal tissue injury. Connexin43 (Cx43) is a gap junction protein that regulates cell growth and apoptosis. In this study, we investigated the effect of Cx43 on X-ray-induced pyroptosis in the human umbilical vein endothelial cells (HUVECs). METHODS: HUVECs, Cx43 overexpression, and Cx43 knockdown strains were irradiated with 10 Gy. Proteins were detected using western blot analysis. Cell pyroptosis was evaluated using the fluorescence-labeled inhibitor of caspase assay (FLICA) and propidium iodide staining through flow cytometry and confocal microscopy. Cell morphology and cytotoxicity were detected by scanning electron microscopy and lactate dehydrogenase release assay, respectively. RESULTS: Irradiation with 10 Gy X-ray induced pyroptosis in the HUVECs and reduced Cx43 expression. The pyroptosis in the HUVECs was significantly attenuated by overexpression of Cx43 as it decreased the level of active caspase-1. However, interference of Cx43 expression with siRNA significantly promoted pyroptosis by increasing the active caspase-1 level. Pannexin1 (Panx1), a gap junction protein regulates pyroptosis, and its cleaved form is used to evaluate channel opening and active state. The level of cleaved Panx1 in the HUVECs and Cx43 knockdown strains increased in the presence of X-ray, but decreased in the Cx43 overexpression strains. Furthermore, interference of Panx1 with siRNA alleviated the upregulation of pyroptosis caused by Cx43 knockdown. CONCLUSION: Results suggest that single high-dose X-ray irradiation induces pyroptosis in the HUVECs. In addition, Cx43 regulates pyroptosis directly by activating caspase-1 or indirectly by cleaving Panx1.


Assuntos
Caspase 1/genética , Conexina 43/genética , Regulação da Expressão Gênica/efeitos da radiação , Células Endoteliais da Veia Umbilical Humana/efeitos da radiação , Piroptose , Raios X/efeitos adversos , Caspase 1/metabolismo , Conexina 43/metabolismo , Conexinas/genética , Conexinas/metabolismo , Células Endoteliais da Veia Umbilical Humana/fisiologia , Humanos , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo
13.
PLoS Negl Trop Dis ; 13(4): e0006843, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30943209

RESUMO

BACKGROUND: Clonorchis sinensis is a group I bio-carcinogen responsible for cholangiocarcinoma (CHCA) in humans. However, the mechanism by which C. sinensis promotes carcinogenesis is unclear. METHODOLOGY: Using the human cholangiocyte line H69, we investigated cell proliferation and gap junction protein expression after stimulation with the hepatotoxin N-nitrosodimethylamine (NDMA) and/or excretory-secretory products (ESP) of C. sinensis, which induce inflammation. NDMA and ESP treatment increased proliferation by 146% and the proportion of cells in the G2/M phase by 37%. Moreover, the expression of the cell proliferation-related proteins E2F1, Ki-67, and cancer related protein cytokeratin 19 and Cox-2 increased in response to combined treatment with NDMA and ESP. The gap-junction proteins connexin (Cx) 43 and Cx26 increased. In contrast, Cx32 expression decreased in cells treated with NDMA and ESP. Silencing of Cx43 reduced cell proliferation and significantly suppressed Cx26 and Cox-2 expression. CONCLUSIONS: These results suggest that Cx43 is an important factor in CHCA induced by C. sinensis ESP and NDMA and further investigations targeting this pathway may allow prevention of this deadly disease.


Assuntos
Carcinogênese/patologia , Carcinógenos/toxicidade , Clonorchis sinensis/metabolismo , Conexina 43/metabolismo , Dimetilnitrosamina/toxicidade , Células Epiteliais/efeitos dos fármacos , Animais , Carcinogênese/metabolismo , Carcinógenos/metabolismo , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Transformação Celular Neoplásica , Colangiocarcinoma/induzido quimicamente , Conexina 43/genética , Conexinas/metabolismo , Células Epiteliais/metabolismo , Inativação Gênica , Proteínas de Helminto/metabolismo , Humanos
14.
Mol Med Rep ; 19(5): 3743-3755, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30896818

RESUMO

Gap junctions (GJs) formed by connexins (Cxs) in T lymphocytes have been reported to have important roles in the T lymphocyte­driven inflammatory response and hypertension­mediated inflammation. Estrogen has a protective effect on cardiovascular diseases, including hypertension and it attenuates excessive inflammatory responses in certain autoimmune diseases. However, the mechanisms involved in regulating the pro­inflammatory response are complex and poorly understood. The current study investigated whether ß­estradiol suppresses hypertension and pro­inflammatory stimuli­mediated inflammatory responses by regulating Cxs and Cx­mediated GJs in peripheral blood lymphocytes. Male, 16­week­old spontaneously hypertensive rats (SHR) and Wistar­Kyoto rats (WKY) rats were randomly divided into the following three groups: WKY rats, vehicle (saline)­treated SHRs, and ß­estradiol (20 µg/kg/day)­treated SHRs. ß­estradiol was administered subcutaneously for 5 weeks. Hematoxylin and eosin staining was performed to evaluate target organ injury. Flow cytometry and ELISA were used to measure the populations of T lymphocyte subtypes in the peripheral blood, and expression of Cx40/Cx43 in T cell subtypes, and pro­inflammation cytokines levels, respectively. ELISA, a dye transfer technique, immunofluorescence and immunoblotting were used to analyze the effect of ß­estradiol on pro­inflammatory cytokine secretion, Cx­mediated GJs and the expression of Cxs in concanavalin A (Con A)­stimulated peripheral blood lymphocytes isolated from WKY rat. ß­estradiol significantly decreased blood pressure and inhibited hypertension­induced target organ injury in SHRs. Additionally, ß­estradiol treatment significantly improved the immune homeostasis of SHRs, as demonstrated by the decreased percentage of cluster of differentiation (CD)4+/CD8+ T­cell subset ratio, reduced serum levels of pro­inflammatory cytokines and increased the percentage of CD4+CD25+ T cells. ß­estradiol also markedly reduced the expression of Cx40/Cx43 in T lymphocytes from SHRs. In vitro, ß­estradiol significantly suppressed the production of pro­inflammatory cytokines, reduced communication via Cx­mediated gap junctions and decreased the expression of Cx40/Cx43 in Con A­stimulated lymphocytes. These results indicate that ß­estradiol attenuates inflammation and end organ damage in hypertension, which may be partially mediated via downregulated expression of Cxs and reduced function of Cx­mediated GJ.


Assuntos
Concanavalina A/efeitos adversos , Conexinas/metabolismo , Estradiol/farmacologia , Hipertensão/complicações , Inflamação/etiologia , Inflamação/metabolismo , Linfócitos/efeitos dos fármacos , Linfócitos/metabolismo , Animais , Pressão Sanguínea/efeitos dos fármacos , Conexina 43/genética , Conexina 43/metabolismo , Conexinas/genética , Citocinas/sangue , Citocinas/metabolismo , Junções Comunicantes/metabolismo , Expressão Gênica , Hipertensão/fisiopatologia , Inflamação/patologia , Mediadores da Inflamação/metabolismo , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Ativação Linfocitária/efeitos dos fármacos , Masculino , Ratos , Remodelação Vascular/efeitos dos fármacos
15.
Eur J Pharmacol ; 853: 84-92, 2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-30880182

RESUMO

Overexpression of connexin 43 (Cx43) was related to dysfunction of vascular smooth muscle cells (VSMCs). Our previous study reported that rutaecarpine, an active ingredient of herbal medicine Evodia, modulated connexins expression in human umbilical vein endothelial cells. This study aims to explore the effects of rutaecarpine on Cx43 expression and VSMCs dysfunction induced by oxidized low-density lipoprotein (ox-LDL). In cultured rat thoracic aortic VSMCs, ox-LDL upregulated the level of Cx43 in a time- and dose-dependent manner, which were abolished by the NF-κB inhibitor BAY11-7082 and PDTC. Furthermore, exposure to ox-LDL for 4 h induced the nuclear translocation of the NF-κB p65 in VMSCs. Ox-LDL (50 mg/l,48 h) induced dysfunction of VSMCs, demonstrated as excessive proliferation, migration, and phenotype switch of cells, which were attenuated by treatment with Cx43 gap junction blocker Gap26(100 µM)) or rutaecarpine (1, 3, and 10 µM). Rutaecarpine inhibited ox-LDL-induced upregulation of Cx43, prevented nuclear translocation of the NF-κB p65, and increased intracellular calcium level in VSMCs. These effects were abolished by pretreatment with transient receptor potential vanilloid subtype 1 (TRPV1) antagonist capsazepine, intracellular calcium chelator BAPTA-AM or CaM antagonist W-7. In conclusion, this study demonstrated that rutaecarpine inhibited Cx43 overexpression through TRPV1/[Ca2+]i/CaM/NF-κB signal pathway, thereby preventing VSMCs dysfunction induced by ox-LDL. Our study provides a novel mechanism by which rutaecarpine modulate Cx43 expression and VSMC function.


Assuntos
Conexina 43/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Alcaloides Indólicos/farmacologia , Lipoproteínas LDL/efeitos adversos , Músculo Liso Vascular/citologia , Quinazolinas/farmacologia , Animais , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Masculino , NF-kappa B/metabolismo , Fenótipo , Ratos , Ratos Sprague-Dawley , Canais de Cátion TRPV/metabolismo , Regulação para Cima/efeitos dos fármacos
16.
PLoS One ; 14(2): e0208301, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30763348

RESUMO

BACKGROUND: Clinical and experimental data give evidence that transplantation of stem and progenitor cells in myocardial infarction could be beneficial, although the underlying mechanism has remained elusive. Ventricular tachyarrhythmia is the most frequent and potentially lethal complication of myocardial infarction, but the impact of mono nuclear cells on the incidence of ventricular arrhythmia is still not clear. OBJECTIVE: We aimed to characterize the influence of splenic mononuclear cell populations on ventricular arrhythmia after myocardial infarction. METHODS: We assessed electrical vulnerability in vivo in mice with left ventricular cryoinfarction 14 days after injury and intramyocardial injection of specific subpopulations of mononuclear cells (MNCs) (CD11b-positive cells, Sca-1-positive cells, early endothelial progenitor cells (eEPCs)). As positive control group we used embryonic cardiomyocytes (eCMs). Epicardial mapping was performed for analysing conduction velocities in the border zone. Left ventricular function was quantified by echocardiography and left heart catheterization. RESULTS: In vivo pacing protocols induced ventricular tachycardia (VT) in 30% of non-infarcted mice. In contrast, monomorphic or polymorphic VT could be evoked in 94% of infarcted and vehicle-injected mice (p<0.01). Only transplantation of eCMs prevented post-infarction VT and improved conduction velocities in the border zone in accordance to increased expression of connexin 43. Cryoinfarction resulted in a broad aggravation of left ventricular function. All transplanted cell types augmented left ventricular function to a similar extent. CONCLUSIONS: Transplantation of different MNC populations after myocardial infarction improves left ventricular function similar to effects of eCMs. Prevention of inducible ventricular arrhythmia is only seen after transplantation of eCMs.


Assuntos
Arritmias Cardíacas/terapia , Infarto/terapia , Leucócitos Mononucleares/fisiologia , Infarto do Miocárdio/terapia , Animais , Arritmias Cardíacas/metabolismo , Antígeno CD11b/metabolismo , Conexina 43/metabolismo , Células Progenitoras Endoteliais/metabolismo , Mapeamento Epicárdico/métodos , Infarto/metabolismo , Leucócitos Mononucleares/metabolismo , Proteínas de Membrana/metabolismo , Camundongos , Infarto do Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/fisiologia , Taquicardia Ventricular/metabolismo , Taquicardia Ventricular/terapia , Função Ventricular Esquerda/fisiologia
17.
Biochim Biophys Acta Mol Cell Res ; 1866(5): 828-838, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30769008

RESUMO

Connexin 43 (Cx43) expression is associated with an increased cell migration and related changes of the actin cytoskeleton (enhanced filopodia formation). These effects are mediated by the C-terminal cytoplasmic part of Cx43 in a channel-independent manner. Since this part has been shown to interact with a variety of proteins and has multiple phosphorylation sites we analyzed here a potential role of the protein kinase A (PKA) for the Cx43 mediated increase in cell migration. Mutation of the PKA-phosphorylation site (substitution of three serines by alanine or glycine) resulted in a further increase in cell motility compared to wild-type Cx43, but with a loss of directionality. Likewise, cell motility was enhanced by PKA inhibition only in Cx43 expressing cells, while reduced in the presence of the PKA activator forskolin. In contrast, cell motility remained unaffected by stimulation with forskolin in cells expressing Cx43 with the mutated PKA phosphorylation site (Cx43-PKA) as well as in Cx-deficient cells. Moreover, PKA activation resulted in increased binding of PKA and VASP to Cx43 associated with an enhanced phosphorylation of VASP, an important regulatory protein of cell polarity and directed migration. Functionally, we could confirm these results in endothelial cells endogenously expressing Cx43. A Tat-Cx43 peptide containing the PKA phosphorylation site abolished the PKA dependent reduction in endothelial cell migration. Our results indicate that PKA dependent phosphorylation of Cx43 modulates cell motility and plays a pivotal role in regulating directed cell migration.


Assuntos
Movimento Celular , Conexina 43/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Células Endoteliais/metabolismo , Citoesqueleto de Actina/genética , Citoesqueleto de Actina/metabolismo , Colforsina/farmacologia , Conexina 43/genética , Proteínas Quinases Dependentes de AMP Cíclico/antagonistas & inibidores , Proteínas Quinases Dependentes de AMP Cíclico/genética , Células Endoteliais/citologia , Ativação Enzimática/efeitos dos fármacos , Ativação Enzimática/genética , Células HeLa , Humanos , Fosforilação/efeitos dos fármacos , Fosforilação/genética
18.
Anal Cell Pathol (Amst) ; 2019: 7145198, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30809467

RESUMO

Objective: To assess the expression levels of exchange protein 1 directly activated by cAMP (Epac1) and phosphodiesterase 4 (PDE4) in rectal carcinoma, and their associations with clinicopathological indexes. In addition, the associations of PDE4 and Epac1 with A-kinase anchor protein 95, connexin 43, cyclin D1, and cyclin E1 were evaluated. Methods: The PV-9000 two-step immunohistochemistry method was used to determine protein expression in 44 rectal carcinoma tissue samples and 16 paracarcinoma tissue specimens. Results: The positive rate of PDE4 protein expression in rectal carcinoma tissues was higher than that of paracarcinoma tissues (59.09% vs. 12.5%, P < 0.05). Similar findings were obtained for Epac1 (55% vs. 6.25%, P < 0.05). No significant associations of PDE4 and Epac1 with degree of differentiation, histological type, and lymph node metastasis were found in rectal carcinoma (P > 0.05). Correlations between PDE4 and Epac1, PDE4 and Cx43, PDE4 and cyclin E1, and Epac1 and Cx43 were observed (all P < 0.05). There was no correlation between the other protein pairs examined (P > 0.05). Conclusion: PDE4 and Epac1 expression levels are increased in rectal carcinoma tissues, suggesting that the two proteins may be involved in the development of this malignancy. Meanwhile, correlations between PDE4 and Epac1, PDE4 and Cx43, PDE4 and cyclin E1, and Epac1 and Cx43 suggested synergistic effects of these proteins in promoting rectal carcinoma.


Assuntos
Carcinoma/metabolismo , AMP Cíclico/metabolismo , Nucleotídeo Cíclico Fosfodiesterase do Tipo 4/metabolismo , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Neoplasias Retais/metabolismo , Proteínas de Ancoragem à Quinase A/metabolismo , Adulto , Idoso , Conexina 43/metabolismo , Ciclina D1/metabolismo , Ciclina E/metabolismo , Feminino , Humanos , Técnicas In Vitro , Masculino , Pessoa de Meia-Idade , Proteínas Oncogênicas/metabolismo , Transdução de Sinais/genética , Transdução de Sinais/fisiologia
19.
Med Sci Monit ; 25: 357-364, 2019 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-30635549

RESUMO

BACKGROUND Karoshi, which is sudden death associated with overwork, has become a serious problem in China. Many studies have examined the relationship between cardiovascular risks and karoshi, but there is little evidence that explains the exact mechanism by which overwork induces sudden death. In these cases, there are few obvious positive findings from forensic autopsies except for histories of overwork prior to death. Therefore, we assume that abnormalities, such as cardiac arrhythmia, rather than organic changes are the cause of karoshi. MATERIAL AND METHODS In the present study, the forced swim test (FST) was used to establish models of overwork. The myocardial tissues of SD rats taking FST (1 h per day, for 30 consecutive days) were collected. The arrhythmia-related molecule CX43 as well as its upstream regulation molecule Cav-1 and cSrc were tested by Western blot (WB) and immunohistochemistry (IHC). HE staining and Masson's staining were performed in the myocardium tissue section. RESULTS We observed downregulation of caveolin-1 (Cav1) followed by cSrc activation, resulting in the decrease of connexin43 (Cx43) levels in overwork models. Myocardial interstitial fibrosis, which is associated with electrophysiological aberrances that result in arrhythmia, was also found in the overwork models. CONCLUSIONS These data provide a mechanistic explanation for the speculated link between karoshi and cardiac arrhythmias.


Assuntos
Arritmias Cardíacas/fisiopatologia , Morte por Excesso de Trabalho/etiologia , Animais , Arritmias Cardíacas/mortalidade , Caveolina 1/metabolismo , China , Conexina 43/metabolismo , Morte Súbita Cardíaca/etiologia , Modelos Animais de Doenças , Fibrose/patologia , Humanos , Masculino , Miocárdio/patologia , Doenças Profissionais , Ratos , Ratos Sprague-Dawley , Fatores de Risco , Estresse Psicológico/fisiopatologia
20.
Biochem Biophys Res Commun ; 509(3): 728-733, 2019 02 12.
Artigo em Inglês | MEDLINE | ID: mdl-30626485

RESUMO

In bone, connexin43 expression in cells of the osteoblast lineage plays an important role in restraining osteoclastogenesis and bone resorption. While there is a consensus around the notion that the anti-osteoclastogenic factor, osteoprotegerin, is a driver of this effect, how connexin43 regulates osteoprotegerin gene expression is unclear. Here, we show that loss of connexin43 decreased osteoprotegerin gene expression and reduced ERK1/2 activation. Conversely, overexpression of connexin43 increased osteoprotegerin expression and enhanced ERK1/2 activation. This increase in phospho-ERK1/2 is required for connexin43 to induce transcription from the osteoprotegerin proximal promoter. Connexin43 increased promoter activity via a specific 200 base pair region of the osteoprotegerin promoter located at -1486 to -1286 with respect to the transcriptional start site, a region which includes four Sp1 binding elements. Further, activation of this promoter region required an intact functional connexin43, as hypomorphic or dominant negative connexin43 mutant constructs, including one with increased hemichannel activity, were unable to stimulate osteoprotegerin expression as strongly as wild type connexin43. Using chromatin immunoprecipitations, we show that connexin43 expression enhanced the recruitment of Sp1, but not Runx2, to the osteoprotegerin proximal promoter. In total, these data show that connexin43-dependent gap junctional communication among osteoblast cells permits efficient ERK1/2 activation. ERK1/2 signaling promotes the recruitment of the potent transcriptional activator, Sp1, to the osteoprotegerin proximal promoter, resulting in robust transcription of anti-osteoclastogenic factor, osteoprotegerin.


Assuntos
Conexina 43/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Osteoprotegerina/genética , Fator de Transcrição Sp1/metabolismo , Ativação Transcricional , Animais , Células Cultivadas , Camundongos Endogâmicos C57BL , Osteoblastos/citologia , Osteoblastos/metabolismo , Regiões Promotoras Genéticas
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