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1.
Heliyon ; 9(2): e13722, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36873153

RESUMO

Zinc depletion is associated with alcohol-associated liver injury. We tested the hypothesis that increasing zinc availability along with alcohol consumption prevents alcohol-associated liver injury. Zinc-glutathione (ZnGSH) was synthesized and directly added to Chinese Baijiu. Mice were administered a single gastric dose of 6 g/kg ethanol in Chinese Baijiu with or without ZnGSH. ZnGSH in Chinese Baijiu did not change the likeness of the drinkers but significantly reduced the recovery time from drunkenness along with elimination of high-dose mortality. ZnGSH in Chinese Baijiu decreased serum AST and ALT, suppressed steatosis and necrosis, and increased zinc and GSH concentrations in the liver. It also increased alcohol dehydrogenase and aldehyde dehydrogenase in the liver, stomach, and intestine and reduced acetaldehyde in the liver. Thus, ZnGSH in Chinese Baijiu prevents alcohol-associated liver injury by increasing alcohol metabolism timely with alcohol consumption, providing an alternative approach to the management of alcohol-associated drinking.

2.
Exp Biol Med (Maywood) ; 246(24): 2671-2678, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34525859

RESUMO

Dietary cholesterol supplements cause hypercholesterolemia and atherosclerosis along with a reduction of copper concentrations in the atherosclerotic wall in animal models. This study was to determine if target-specific copper delivery to the copper-deficient atherosclerotic wall can block the pathogenesis of atherosclerosis. Male New Zealand white rabbits, 10-weeks-old and averaged 2.0 kg, were fed a diet containing 1% (w/w) cholesterol or the same diet without cholesterol as control. Twelve weeks after the feeding, the animals were injected with copper-albumin microbubbles and subjected to ultrasound sonication specifically directed at the atherosclerotic lesions (Cu-MB-US) for target-specific copper delivery, twice a week for four weeks. This regiment was repeated 3 times with a gap of two weeks in between. Two weeks after the last treatment, the animals were harvested for analyses of serum and aortic pathological changes. Compared to controls, rabbits fed cholesterol-rich diet developed atherosclerotic lesion with a reduction in copper concentrations in the lesion tissue. Cu-MB-US treatment significantly increased copper concentrations in the lesion, and reduced the size of the lesion. Furthermore, copper repletion reduced the number of apoptotic cells as well as the content of cholesterol and phospholipids in the atherosclerotic lesion without a disturbance of the stability of the lesion. The results thus demonstrate that target-specific copper supplementation suppresses the progression of atherosclerosis at least in part through preventing endothelial cell death, thus reducing lipid infiltration in the atherosclerotic lesion.


Assuntos
Aterosclerose/patologia , Cobre/administração & dosagem , Microbolhas , Ultrassom , Animais , Aorta Abdominal/patologia , Colesterol na Dieta/toxicidade , Dieta Hiperlipídica/efeitos adversos , Sistemas de Liberação de Medicamentos , Masculino , Coelhos , Ultrassom/métodos
3.
J Nutr Biochem ; 97: 108802, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34119631

RESUMO

Zinc deficiency is common in the liver of patients with chronic liver disease. Zinc supplementation suppresses the progression of liver fibrosis induced by bile duct ligation (BDL) in mice. The present study was undertaken to specifically investigate a possible mechanism by which zinc plays this role in the liver. Kunming mice were subjected to BDL for 4 weeks to induce liver fibrosis, and concomitantly treated with zinc sulfite or saline as control by gavage once a day. The results showed that zinc supplementation significantly suppressed liver fibrosis and inflammation along with inhibition of hepatic stellate cells activation induced by BDL. These inhibitory effects were accompanied by the reduction of collagen deposition and a significant reduction of macrophage infiltration affected livers. Importantly, zinc selectively inhibited M1 macrophage polarization and M1-related inflammatory cytokines. This inhibitory effect was further confirmed by the reduction of relevant biomarkers of M1 macrophages including inducible NO synthase (iNOS), monocyte chemotactic protein-1 (MCP-1/CCL2), and tumor necrosis factor-α in the zinc supplemented BDL livers. In addition, zinc inhibition of M1 macrophages was associated with a decrease of Notch1 expression. Taken together, these data indicated that zinc supplementation inhibited liver inflammation and fibrosis in BDL mice through selective suppression of M1 macrophages, which is associated with inhibition of Notch1 pathway in M1 macrophage polarization.


Assuntos
Suplementos Nutricionais , Cirrose Hepática/prevenção & controle , Fígado/imunologia , Macrófagos/fisiologia , Zinco/administração & dosagem , Animais , Animais não Endogâmicos , Inflamação/prevenção & controle , Ativação de Macrófagos , Macrófagos/imunologia , Masculino , Camundongos , Receptor Notch1/metabolismo , Transdução de Sinais
4.
Exp Biol Med (Maywood) ; 245(10): 911-921, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32148090

RESUMO

IMPACT STATEMENT: Copper promotes angiogenesis, but the mechanistic insights have not been fully elucidated until recently. In addition, the significance of copper promotion of angiogenesis in myocardial regeneration was increasingly revealed. Copper critically participates in the regulation of hypoxia-inducible factor 1 (HIF-1) of angiogenic gene expression. Interestingly, myocardial ischemia causes copper efflux from the heart, leading to suppression of angiogenesis, although HIF-1α, the critical subunit of HIF-1, remains accumulated in the ischemic myocardium. Strategies targeting copper specific delivery to the ischemic myocardium lead to selective activation of HIF-1-regulated angiogenic gene expression. Vascularization of the ischemic myocardium re-establishes the tissue injury microenvironment, and rebuilds the conduit for communication between the tissue injury signals and the remote regenerative responses including stem cells. This process promotes myocardial regeneration. Thus, a simple and effective copper supplementation to the ischemic myocardium would become a novel therapeutic approach to the treatment of patients with ischemic heart diseases.


Assuntos
Cobre/metabolismo , Coração/fisiologia , Isquemia Miocárdica , Miocárdio/metabolismo , Neovascularização Fisiológica/fisiologia , Regeneração/fisiologia , Animais , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo
5.
Exp Cell Res ; 388(2): 111859, 2020 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-31972217

RESUMO

Mesenchymal stem cells (MSCs) are widely studied for their application in cell therapy. A noticed drawback of these cells in response to tissue injury is the low efficiency of homing. The present study was undertaken to explore a possible approach to promote the migration of MSCs. Primary cultures of rat adipose-derived stem cells (rADSCs) were cultured in standard L-DMEM media supplemented with or without copper (Cu) at its final concentration of 20 µM in cultures. The analyses of transwell and wound-healing assay revealed that Cu supplementation significantly promotes the migration of rADSCs in cultures. Further analysis found that Cu stimulated the phosphorylation of vimentin Ser39. Point mutation of vimentin Ser39 by substituting Ser with Ala prevented Cu-promoted migration of rADSCs. This study thus demonstrates that Cu promotes migration of rADSCs in cultures through at least in part Cu stimulation of vimentin Ser39 phosphorylation.


Assuntos
Diferenciação Celular , Movimento Celular , Proliferação de Células , Cobre/farmacologia , Células-Tronco Mesenquimais/citologia , Vimentina/metabolismo , Animais , Células Cultivadas , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/metabolismo , Fosforilação , Ratos , Ratos Sprague-Dawley , Cicatrização
6.
Metallomics ; 7(9): 1331-7, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26168186

RESUMO

Dietary copper supplementation reverses the pressure overload-induced cardiac hypertrophy. Activation of vascular endothelial growth factor receptor-1 (VEGFR-1) and cyclic guanosine monophosphate (cGMP)-dependent protein kinase-1 (PKG-1) is required for the regression. The present study was undertaken to determine the link between VEGFR-1 and PKG-1 in copper regression of cardiomyocyte hypertrophy. Human cardiac myocytes (HCM) or primary cultures of neonatal rat cardiomyocytes were exposed to phenylephrine (PE) at a final concentration of 100 µM for 48 h to induce cell hypertrophy. Copper sulfite was added to cultures of hypertrophic cardiomyocytes at a final concentration of 5 µM elemental copper and incubated for 24 h to reverse cell hypertrophy. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis identified a 56 kDa copper-binding protein, vimentin, which was co-immunoprecipitated with VEGFR-1 and PKG-1. Copper supplementation increased vimentin levels and enhanced PKG-1 activity. Gene silencing using siRNA targeting vimentin prevented copper-induced elevation of vimentin, depressed the activity of PKG-1, and blocked the copper-induced regression of cardiomyocyte hypertrophy. This study demonstrates that vimentin is critically involved in the VEGFR-1 mediated activation of the PKG-1 signaling pathway, leading to regression of cardiomyocyte hypertrophy.


Assuntos
Cardiomegalia/metabolismo , Cobre/metabolismo , Proteínas Quinases Dependentes de GMP Cíclico/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Vimentina/metabolismo , Vimentina/farmacologia , Animais , Células Cultivadas , Humanos , Ratos , Ratos Wistar , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Vimentina/química , Vimentina/genética
7.
Pharmacol Ther ; 148: 66-84, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25476109

RESUMO

Pressure overload causes an accumulation of homocysteine in the heart, which is accompanied by copper depletion through the formation of copper-homocysteine complexes and the excretion of the complexes. Copper supplementation recovers cytochrome c oxidase (CCO) activity and promotes myocardial angiogenesis, along with the regression of cardiac hypertrophy and the recovery of cardiac contractile function. Increased copper availability is responsible for the recovery of CCO activity. Copper promoted expression of angiogenesis factors including vascular endothelial growth factor (VEGF) in endothelial cells is responsible for angiogenesis. VEGF receptor-2 (VEGFR-2) is critical for hypertrophic growth of cardiomyocytes and VEGFR-1 is essential for the regression of cardiomyocyte hypertrophy. Copper, through promoting VEGF production and suppressing VEGFR-2, switches the VEGF signaling pathway from VEGFR-2-dependent to VEGFR-1-dependent, leading to the regression of cardiomyocyte hypertrophy. Copper is also required for hypoxia-inducible factor-1 (HIF-1) transcriptional activity, acting on the interaction between HIF-1 and the hypoxia responsible element and the formation of HIF-1 transcriptional complex by inhibiting the factor inhibiting HIF-1. Therefore, therapeutic targets for copper supplementation-induced regression of cardiac hypertrophy include: (1) the recovery of copper availability for CCO and other critical cellular events; (2) the activation of HIF-1 transcriptional complex leading to the promotion of angiogenesis in the endothelial cells by VEGF and other factors; (3) the activation of VEGFR-1-dependent regression signaling pathway in the cardiomyocytes; and (4) the inhibition of VEGFR-2 through post-translational regulation in the hypertrophic cardiomyocytes. Future studies should focus on target-specific delivery of copper for the development of clinical application.


Assuntos
Cardiomegalia/metabolismo , Cobre/metabolismo , Animais , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Humanos , Fator 1 Induzível por Hipóxia/metabolismo , Miócitos Cardíacos/metabolismo , Neovascularização Fisiológica
8.
Exp Biol Med (Maywood) ; 240(9): 1197-204, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25432983

RESUMO

Metallothionein (MT) gene therapy leads to resolution of liver fibrosis in mouse model, in which the activation of collagenases is involved in the regression of liver fibrosis. MT plays a critical role in zinc sequestration in the liver suggesting its therapeutic effect would be mediated by zinc. The present study was undertaken to test the hypothesis that zinc supplementation suppresses liver fibrosis. Male Kunming mice subjected to bile duct ligation (BDL) resulted in liver fibrosis as assessed by increased α-smooth muscle actin (α-SMA) and collagen I production/deposition in the liver. Zinc supplementation was introduced 4 weeks after BDL surgery via intragastric administration once daily for 2 weeks resulting in a significant reduction in the collagen deposition in the liver and an increase in the survival rate. Furthermore, zinc suppressed gene expression of α-SMA and collagen I and enhanced the capacity of collagen degradation, as determined by the increased activity of total collagenases and elevated mRNA and protein levels of MMP13. Therefore, the results demonstrate that zinc supplementation suppresses BDL-induced liver fibrosis through both inhibiting collagen production and enhancing collagen degradation.


Assuntos
Cirrose Hepática Experimental/prevenção & controle , Zinco/administração & dosagem , Actinas/genética , Actinas/metabolismo , Animais , Ductos Biliares , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Colagenases/genética , Colagenases/metabolismo , Suplementos Nutricionais , Modelos Animais de Doenças , Ligadura , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática Experimental/etiologia , Cirrose Hepática Experimental/metabolismo , Masculino , Metaloproteinase 13 da Matriz/genética , Metaloproteinase 13 da Matriz/metabolismo , Camundongos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transcriptoma , Zinco/sangue , Zinco/metabolismo
9.
Exp Biol Med (Maywood) ; 239(8): 948-953, 2014 08.
Artigo em Inglês | MEDLINE | ID: mdl-24903162

RESUMO

Previous studies revealed that copper (Cu)-induced regression of cardiomyocyte hypertrophy is associated with enhanced activity in the vascular endothelial growth factor receptor-1 (VEGFR-1) signaling pathway. The mechanism by which Cu enhances the activity of VEGFR-1 pathway remains to be defined. The present study was undertaken to test the hypothesis that Cu enhances the VEGFR-1 signaling pathway via suppression of the VEGFR-2 signaling pathway. Primary cultures of neonatal rat cardiomyocytes were exposed to phenylephrine (PE) at a final concentration of 100 µM in cultures for 48 h to induce cell hypertrophy. The hypertrophic cardiomyocytes were exposed to copper sulfate at a final concentration of 5 µM Cu in cultures for 24 h. Western blot analysis showed that PE increased the protein levels of both VEGFR-1 and VEGFR-2. Cu supplementation significantly reduced the increase in VEGFR-2, but had no effect on the elevation of VEGFR-1. Real-time polymerase chain reaction analysis found no difference in the mRNA levels between the VEGFR-1 and VEGFR-2 under the conditions defined above. This study thus demonstrated that Cu selectively suppressed PE-elevated VEGFR-2 levels likely via post-translational regulation, leading to the VEGFR-1 signaling pathway becoming dominant and thereby regressing cardiomyocyte hypertrophy.

10.
Metallomics ; 6(3): 554-9, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24343031

RESUMO

Copper chaperones are critical regulators of intracellular copper metabolism and distribution. The present study was undertaken to investigate the effects of changes in copper concentrations on the abundance of copper chaperones. Human umbilical vein endothelial cells (HUVECs) were treated with siRNA targeting copper transporter 1 (CTR1) or tetraethylenepentamine (TEPA) to decrease, or with copper sulfide to increase, intracellular copper concentrations, assayed using an atomic absorption spectrophotometer. Western blot analyses showed that CTR1 silencing or TEPA treatment increased the protein levels of copper chaperone ATOX1 and copper chaperone for superoxide dismutase 1 (CCS-1), but decreased copper chaperone for cytochrome c oxidase (COX17). In contrast, copper supplementation decreased the protein levels of ATOX1 and CCS-1 and increased COX17. Real-time RT-PCR analyses found no difference in the mRNA levels of the copper chaperones examined under the conditions defined above. This study thus demonstrated that changes in copper concentrations alter the protein levels, but not the mRNA levels, of copper chaperones, suggesting a role of copper in the post-translational modification of these proteins.


Assuntos
Proteínas de Transporte/metabolismo , Proteínas de Transporte de Cátions/metabolismo , Cobre/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Chaperonas Moleculares/metabolismo , RNA Mensageiro/genética , Proteínas de Transporte/genética , Proteínas de Transporte de Cátions/genética , Proteínas de Transporte de Cobre , Transportador de Cobre 1 , Humanos , Chaperonas Moleculares/genética , Interferência de RNA , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/genética
11.
PLoS One ; 8(6): e67549, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23818984

RESUMO

Cardiomyocyte hypertrophy induced by phenylephrine (PE) is accompanied by suppression of cytochrome c oxidase (CCO) activity, and copper (Cu) supplementation restores CCO activity and reverses the hypertrophy. The present study was aimed to understand the mechanism of PE-induced decrease in CCO activity. Primary cultures of neonatal rat cardiomyocytes were treated with PE at a final concentration of l00 µM in cultures for 72 h to induce cell hypertrophy. The CCO activity was determined by enzymatic assay and changes in CCO subunit COX-IV as well as copper chaperones for CCO (COX17, SCO2, and COX11) were determined by Western blotting. PE treatment increased both intracellular and extracellular homocysteine concentrations and decreased intracellular Cu concentrations. Studies in vitro found that homocysteine and Cu form complexes. Inhibition of the intracellular homocysteine synthesis in the PE-treated cardiomyocytes prevented the increase in the extracellular homocysteine concentration, retained the intracellular Cu concentration, and preserved the CCO activity. PE treatment decreased protein concentrations of the COX-IV, and the Cu chaperones COX17, COX11, and SCO2. These PE effects were prevented by either inhibition of the intracellular homocysteine synthesis or Cu supplementation. Therefore, PE-induced elevation of homocysteine restricts Cu availability through its interaction with Cu and suppression of Cu chaperones, leading to the decrease in CCO enzyme activity.


Assuntos
Cobre/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Homocisteína/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Fenilefrina/farmacologia , Animais , Animais Recém-Nascidos , Ligação Competitiva/efeitos dos fármacos , Western Blotting , Proteínas de Transporte/metabolismo , Proteínas de Transporte de Cátions/metabolismo , Forma Celular/efeitos dos fármacos , Células Cultivadas , Proteínas de Transporte de Cobre , Espaço Extracelular/efeitos dos fármacos , Espaço Extracelular/metabolismo , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Proteínas Mitocondriais/metabolismo , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Ratos , Ratos Sprague-Dawley
12.
Free Radic Biol Med ; 53(8): 1595-606, 2012 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-22819979

RESUMO

Oxidative stress induced by maternal diabetes plays an important role in the development of cardiac malformations. Zinc (Zn) supplementation of animals and humans has been shown to ameliorate oxidative stress induced by diabetic cardiomyopathy. However, the role of Zn in the prevention of oxidative stress induced by diabetic cardiac embryopathy remains unknown. We analyzed the preventive role of Zn in diabetic cardiac embryopathy by both in vivo and in vitro studies. In vivo study revealed a significant decrease in lipid peroxidation, superoxide ions, and oxidized glutathione and an increase in reduced glutathione, nitric oxide, and superoxide dismutase in the developing heart at embryonic days (E) 13.5 and 15.5 in the Zn-supplemented diabetic group when compared to the diabetic group. In addition, significantly down-regulated protein and mRNA expression of metallothionein (MT) in the developing heart of embryos from diabetic group was rescued by Zn supplement. Further, the nuclear microscopy results showed that trace elements such as phosphorus, calcium, and Zn levels were significantly increased (P<0.001), whereas the iron level was significantly decreased (P<0.05) in the developing heart of embryos from the Zn-supplemented diabetic group. In vitro study showed a significant increase in cellular apoptosis and the generation of reactive oxygen species (ROS) in H9c2 (rat embryonic cardiomyoblast) cells exposed to high glucose concentrations. Supplementation with Zn significantly decreased apoptosis and reduced the levels of ROS. In summary, oxidative stress induced by maternal diabetes could play a role in the development and progression of cardiac embryopathy, and Zn supplementation could be a potential therapy for diabetic cardiac embryopathy.


Assuntos
Apoptose/efeitos dos fármacos , Diabetes Mellitus Experimental/fisiopatologia , Suplementos Nutricionais , Embrião de Mamíferos/efeitos dos fármacos , Cardiopatias Congênitas/prevenção & controle , Estresse Oxidativo , Zinco/administração & dosagem , Animais , Glicemia/metabolismo , Western Blotting , Células Cultivadas , Complicações do Diabetes/etiologia , Complicações do Diabetes/patologia , Complicações do Diabetes/prevenção & controle , Embrião de Mamíferos/citologia , Embrião de Mamíferos/metabolismo , Feminino , Glutationa/genética , Glutationa/metabolismo , Cardiopatias Congênitas/etiologia , Cardiopatias Congênitas/patologia , Técnicas Imunoenzimáticas , Peroxidação de Lipídeos/efeitos dos fármacos , Metalotioneína/genética , Metalotioneína/metabolismo , Camundongos , Miócitos Cardíacos/citologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Microscopia Nuclear , RNA Mensageiro/genética , Ratos , Espécies Reativas de Oxigênio/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo
13.
Pharmacol Ther ; 135(3): 337-54, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22750195

RESUMO

Pathological cardiac hypertrophy is a key risk factor for heart failure. It is associated with increased interstitial fibrosis, cell death and cardiac dysfunction. The progression of pathological cardiac hypertrophy has long been considered as irreversible. However, recent clinical observations and experimental studies have produced evidence showing the reversal of pathological cardiac hypertrophy. Left ventricle assist devices used in heart failure patients for bridging to transplantation not only improve peripheral circulation but also often cause reverse remodeling of the geometry and recovery of the function of the heart. Dietary supplementation with physiologically relevant levels of copper can reverse pathological cardiac hypertrophy in mice. Angiogenesis is essential and vascular endothelial growth factor (VEGF) is a constitutive factor for the regression. The action of VEGF is mediated by VEGF receptor-1, whose activation is linked to cyclic GMP-dependent protein kinase-1 (PKG-1) signaling pathways, and inhibition of cyclic GMP degradation leads to regression of pathological cardiac hypertrophy. Most of these pathways are regulated by hypoxia-inducible factor. Potential therapeutic targets for promoting the regression include: promotion of angiogenesis, selective enhancement of VEGF receptor-1 signaling pathways, stimulation of PKG-1 pathways, and sustention of hypoxia-inducible factor transcriptional activity. More exciting insights into the regression of pathological cardiac hypertrophy are emerging. The time of translating the concept of regression of pathological cardiac hypertrophy to clinical practice is coming.


Assuntos
Cardiomegalia/tratamento farmacológico , Cardiotônicos/uso terapêutico , Terapia de Alvo Molecular/métodos , Neovascularização Fisiológica/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Animais , Cardiomegalia/fisiopatologia , Cardiomegalia/cirurgia , Cardiotônicos/farmacologia , Coração Auxiliar , Humanos , Modelos Cardiovasculares , Neovascularização Fisiológica/fisiologia , Transdução de Sinais/fisiologia
14.
J Pharmacol Exp Ther ; 342(2): 561-7, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22619252

RESUMO

Cobalt inhibits prolyl hydroxylases, leading to the accumulation of hypoxia-inducible factor-1α (HIF-1α) and a concomitant increase in the transcriptional activity of HIF-1. Therefore, cobalt has been under development as a drug for activating HIF-1 under some disease conditions. However, it has been shown that ischemic conditions resulted in the loss of copper, and the activation of HIF-1 would not occur unless copper was supplemented. The present study was undertaken to test the hypothesis that copper is also required for the cobalt activation of HIF-1 transcriptional activity. Human umbilical vein endothelial cells subjected to treatment with cobalt chloride (CoCl(2)) at concentrations above 25 µM for 2 h resulted in an accumulation of HIF-1α, which was determined by Western blot analysis, and an increase in the expression of vascular endothelial growth factor (VEGF), which was determined by real-time reverse transcription-polymerase chain reaction analysis for mRNA levels and enzyme-linked immunosorbent assay analysis for protein levels. The copper chelator tetraethylenepentamine at 25 µM did not significantly affect the accumulation of HIF-1α but blocked increases in VEGF mRNA and protein levels, an effect that could be reversed by the addition of 25 µM copper sulfate (CuSO(4)). In addition, gene silencing of the copper chaperone for Cu,Zn-superoxide dismutase blocked VEGF expression with little effect on cobalt-induced HIF-1α accumulation. The present study thus demonstrates that copper was required for cobalt-activated transcriptional activity of HIF-1, although copper did not affect cobalt-induced accumulation of HIF-1α in the cells.


Assuntos
Cobalto/metabolismo , Cobalto/farmacologia , Cobre/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Ativação Transcricional/efeitos dos fármacos , Células Cultivadas , Sulfato de Cobre/farmacologia , Etilenodiaminas/farmacologia , Inativação Gênica/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , RNA Mensageiro/genética , Superóxido Dismutase/metabolismo , Transcrição Gênica/efeitos dos fármacos , Transcrição Gênica/genética , Ativação Transcricional/genética , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismo
15.
Exp Biol Med (Maywood) ; 237(1): 77-82, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22185917

RESUMO

Studies in vivo have shown that dietary copper (Cu) supplementation reverses pressure overload-induced cardiac hypertrophy in a mouse model, which is vascular endothelial growth factor (VEGF)-dependent and correlates with enhanced angiogenesis. Because Cu stimulation of endothelial cell growth and differentiation would play a critical role in angiogenesis, the present study was undertaken to examine the effect of Cu on growth of human umbilical vein endothelial cells (HUVECs) in cultures. The HUVECs were treated with CuSO(4) at a final concentration of 5 µmol/L Cu element in cultures or with a Cu chelator, tetraethylenepentamine (TEPA), at a final concentration of 25 µmol/L in cultures. Cell growth and Cu effect on cell cycle were determined. In addition, the effect of Cu on VEGF and endothelial nitric oxide synthase (eNOS) mRNA levels was determined, and anti-VEGF antibody and siRNA targeting eNOS were applied to determine the role of VEGF or eNOS in the Cu effect on cell growth. Cu significantly stimulated and TEPA significantly inhibited cell growth, and the TEPA effect was blocked by excess Cu. Cu increased the number of cells in the S phase and correspondingly decreased the number in the G1 phase. Interestingly, Cu did not increase the level of VEGF mRNA, but significantly increased eNOS mRNA. Furthermore, neutralizing VEGF by anti-VEGF antibody did not suppress Cu stimulation of cell growth. However, siRNA targeting eNOS completely blocked Cu reversal of TEPA inhibition of cell growth. The data demonstrate that Cu stimulation of HUVEC cell growth is VEGF-independent, but eNOS-dependent.


Assuntos
Cobre/farmacologia , Células Endoteliais da Veia Umbilical Humana/citologia , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Anticorpos Monoclonais/imunologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sulfato de Cobre/farmacologia , Humanos , Óxido Nítrico Sintase Tipo III/biossíntese , Óxido Nítrico Sintase Tipo III/genética , Interferência de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/imunologia , Fator A de Crescimento do Endotélio Vascular/metabolismo
16.
Toxicol Lett ; 200(3): 194-200, 2011 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-21126564

RESUMO

Cinnabar (HgS) is used in traditional medicines, and total Hg content is used for risk assessment of cinnabar-containing traditional medicines such as Zhu-Sha-An-Shen-Wan (ZSASW). Is ZSASW or cinnabar toxicologically similar to common mercurials? Adult Sprague-Dawley rats were gavaged with ZSASW (1.4 g/kg), cinnabar (0.2g/kg), HgCl(2) (0.02 g/kg), MeHg (0.001 g/kg), or saline daily for 60 days, and toxicity was determined. Animal body-weight gain was decreased by HgCl(2) and MeHg. Blood urea nitrogen (BUN) was increased by MeHg. Histology showed severe kidney injury following MeHg and HgCl(2) treatments, but mild after ZSASW and cinnabar. Renal Hg contents were markedly increased in the HgCl(2) and MeHg groups but were not elevated in the ZSASW and cinnabar groups. The expression of kidney injury molecule-1 was increased 50-fold by MeHg, 4-fold by HgCl(2), but was unaltered by ZSASW and cinnabar; the expression of matrilysin was increased 3-fold by MeHg. In contrast, the expression of N-cadherin was decreased by HgCl(2). Thus, ZSASW and cinnabar are much less nephrotoxic than HgCl(2) and MeHg, indicating that chemical forms of mercury underlie their disposition and toxicity.


Assuntos
Medicamentos de Ervas Chinesas/toxicidade , Cloreto de Mercúrio/toxicidade , Compostos de Mercúrio/toxicidade , Compostos de Metilmercúrio/toxicidade , Animais , Biomarcadores/metabolismo , Análise Química do Sangue , Peso Corporal/efeitos dos fármacos , Primers do DNA , Expressão Gênica/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Nefropatias/induzido quimicamente , Nefropatias/patologia , Masculino , Medicina Tradicional Chinesa , Cloreto de Mercúrio/farmacocinética , Mercúrio/metabolismo , Compostos de Mercúrio/farmacocinética , Intoxicação por Mercúrio/genética , Intoxicação por Mercúrio/patologia , Compostos de Metilmercúrio/farmacocinética , RNA/genética , RNA/isolamento & purificação , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Aumento de Peso/efeitos dos fármacos
17.
Hepatology ; 50(4): 1241-50, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19637192

RESUMO

UNLABELLED: Alcoholic steatosis is a fundamental metabolic disorder in the progression of alcoholic liver disease. Zinc deficiency is one of the most consistently observed biochemical/nutritional manifestations of alcoholic liver disease. The purpose of this study is to determine whether dietary zinc supplementation to mice previously exposed to alcohol could reverse alcoholic steatosis. Male 129S mice were pair-fed an alcohol or isocaloric maltose dextrin liquid diet for 16 weeks with or without dietary zinc supplementation for the last 4 weeks. Zinc supplementation significantly attenuated alcohol-mediated increases in hepatic triglyceride, cholesterol, and free fatty acids in association with accelerated hepatic fatty acid oxidation and very low density lipoproteins (VLDL) secretion. Hepatic genes related to fatty acid oxidation and VLDL secretion were up-regulated by zinc supplementation, which was accompanied by restoring activity of hepatocyte nuclear factor-4alpha (HNF-4alpha) and peroxisome proliferators activated receptor-alpha (PPAR-alpha). Zinc supplementation enhanced alcohol metabolism and attenuated oxidative stress and liver injury. Zinc supplementation also normalized alcohol-mediated increases in plasma triglycerides and partially reversed decrease in gonadal adipose depot mass. Studies in HepG2 cells showed that zinc deprivation significantly suppressed the DNA-binding activities of HNF-4alpha and PPAR-alpha, and reduced HNF-4alpha and PPAR-alpha target proteins. Consequently, zinc deprivation caused cellular accumulation of lipid droplets, triglycerides and free fatty acids in the HepG2 cells. CONCLUSION: Zinc supplementation reverses alcoholic steatosis, and reactivation of HNF-4alpha and PPAR-alpha by increasing zinc availability and inhibiting oxidative stress are potential mechanisms underlying these beneficial effects of zinc on hepatic lipid homeostasis.


Assuntos
Suplementos Nutricionais , Fígado Gorduroso Alcoólico/metabolismo , Fígado Gorduroso Alcoólico/prevenção & controle , Fator 4 Nuclear de Hepatócito/metabolismo , PPAR alfa/metabolismo , Zinco/farmacologia , Alanina Transaminase/metabolismo , Animais , Peso Corporal/efeitos dos fármacos , Linhagem Celular Tumoral , Colesterol/metabolismo , Modelos Animais de Doenças , Ácidos Graxos não Esterificados/metabolismo , Homeostase/efeitos dos fármacos , Homeostase/fisiologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Camundongos , Camundongos Endogâmicos , Tamanho do Órgão/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Triglicerídeos/metabolismo , Zinco/administração & dosagem , Zinco/metabolismo
18.
Curr Med Chem ; 16(10): 1304-14, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19355887

RESUMO

Copper promotion of angiogenesis has been known for more than two decades, but the mechanism of action of copper has not been explored until recently. Copper stimulation of factors involved in vessel formation and maturation, such as vascular endothelial growth factor (VEGF), is mainly responsible for its angiogenesis effect. Copper is required for the activation of hypoxia-inducible factor-1 (HIF-1), a major transcription factor regulating the expression of VEGF. Copper would be transported into nucleus by a copper chaperon for superoxide dismutase-1. Copper is required for HIF-1 interaction with the hypoxia-responsive element of the target genes and ensures the formation of HIF-1 transcriptional complex, thus activating the expression of target genes including VEGF. On the other hand, excess copper can stabilize HIF-1alpha, the rate-limiting component of HIF-1, leading to its accumulation in cytoplasm and thus HIF-1 activation. The essential role of copper in production of VEGF makes it implicated in anti-angiogenesis therapy, such as the application of copper chelators in cancer therapy. However, suppression of angiogenesis is involved in the progression of heart hypertrophy and its transition to heart failure, therefore copper supplementation improves hypertrophic heart disease conditions. This dilemma of copper implications in cancer therapy and heart hypertrophy dictates a comprehensive understanding of a patient's condition before an implementation of copper manipulation therapy for different diseases. In this context, a development of diagnosis for copper metabolic changes as well as a tissue-specific copper manipulation would greatly benefit patients with an implication of copper manipulation therapy.


Assuntos
Cobre/farmacologia , Cobre/uso terapêutico , Neoplasias/tratamento farmacológico , Neovascularização Fisiológica , Antineoplásicos/uso terapêutico , Cardiopatias/tratamento farmacológico , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/efeitos dos fármacos
19.
Cardiovasc Toxicol ; 8(3): 137-44, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18679830

RESUMO

Elevated levels of homocysteine (Hcy) (known as hyperhomocysteinemia HHcy) are involved in dilated cardiomyopathy. Hcy chelates copper and impairs copper-dependent enzymes. Copper deficiency has been linked to cardiovascular disease. We tested the hypothesis that copper supplement regresses left ventricular hypertrophy (LVH), fibrosis and endothelial dysfunction in pressure overload DCM mice hearts. The mice were grouped as sham, sham + Cu, aortic constriction (AC), and AC + Cu. Aortic constriction was performed by transverse aortic constriction. The mice were treated with or without 20 mg/kg copper supplement in the diet for 12 weeks. The cardiac function was assessed by echocardiography and electrocardiography. The matrix remodeling was assessed by measuring matrix metalloproteinase (MMP), tissue inhibitor of metalloproteinases (TIMPs), and lysyl oxidase (LOX) by Western blot analyses. The results suggest that in AC mice, cardiac function was improved with copper supplement. TIMP-1 levels decreased in AC and were normalized in AC + Cu. Although MMP-9, TIMP-3, and LOX activity increased in AC and returned to baseline value in AC + Cu, copper supplement showed no significant effect on TIMP-4 activity after pressure overload. In conclusion, our data suggest that copper supplement helps improve cardiac function in a pressure overload dilated cardiomyopathic heart.


Assuntos
Cardiomiopatia Dilatada/tratamento farmacológico , Cobre/administração & dosagem , Suplementos Nutricionais , Insuficiência Cardíaca/tratamento farmacológico , Hemodinâmica/efeitos dos fármacos , Homocisteína/metabolismo , Hipertrofia Ventricular Esquerda/tratamento farmacológico , Miocárdio/metabolismo , Animais , Aorta/cirurgia , Pressão Sanguínea , Western Blotting , Cardiomiopatia Dilatada/metabolismo , Cardiomiopatia Dilatada/fisiopatologia , Constrição , Cobre/metabolismo , Modelos Animais de Doenças , Ecocardiografia , Eletrocardiografia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Endotélio Vascular/fisiopatologia , Feminino , Fibrose , Insuficiência Cardíaca/metabolismo , Insuficiência Cardíaca/fisiopatologia , Homocisteína/sangue , Hipertrofia Ventricular Esquerda/metabolismo , Hipertrofia Ventricular Esquerda/fisiopatologia , Masculino , Metaloproteinases da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Miocárdio/enzimologia , Miocárdio/patologia , Proteína-Lisina 6-Oxidase/metabolismo , Inibidores Teciduais de Metaloproteinases/metabolismo , Remodelação Ventricular/efeitos dos fármacos
20.
Exp Biol Med (Maywood) ; 233(9): 1059-65, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18535158

RESUMO

Traditional Chinese medicine (TCM) has a long history of development and application and has demonstrated on evidence basis its efficacy in the treatment of many diseases affecting multiple organ systems. In particular, TCM is effective in the prevention and treatment of chronic diseases and metabolic syndromes. However, the value of TCM has not been fully recognized worldwide due to the lack of definitive information of active ingredients in almost any TCM preparation. Novel functional genomics and proteomics approaches provide alternate perspectives on the mechanism of action of TCM. The target molecules on which TCM either activates or inactivates can be identified by functional genomics and proteomics, thus the affected critical signaling pathway cascades leading to effective recovery of chronic diseases can be studied. Several TCM preparations have been available for the treatment of liver fibrosis and cirrhosis, even advanced liver cirrhosis that has been shown to be irreversible and has no US-FDA approved therapy. In the TCM-treated livers with fibrosis and cirrhosis, some critical molecules that are significantly involved in the recovery can be identified through functional genomics and proteomics studies. These molecules become novel targets for drug discovery and development and candidates for the development of gene therapy. Gene therapy developed based on this strategy for the treatment of advanced liver fibrosis and cirrhosis in animal models has obtained promising results. This process thus establishes a herbogenomics approach to understand mechanisms of action of TCM and to identify effective molecular targets for the discovery and development of novel therapeutics.


Assuntos
Medicamentos de Ervas Chinesas/uso terapêutico , Genômica , Medicina Tradicional Chinesa/métodos , Farmacogenética , Animais , Terapia Genética , Humanos , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/genética , Cirrose Hepática/patologia
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