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1.
Arch Med Sci ; 18(5): 1262-1270, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36160342

RESUMO

Introduction: Coronavirus disease 2019 (COVID-19) is associated with severe emotional changes. This research aims to investigate the prevalence of anxiety and depression in COVID-19 patients and its relationship with disease severity, sleep patterns, lifestyle, and specific laboratory test results. Material and methods: An observational study of 52 Chinese patients with COVID-19 was conducted to assess the relation between anxiety and depression (evaluated with the Hospital Anxiety and Depression Scale) and laboratory findings (lymphocytes, C-reactive proteins, leukocytes, alanine aminotransferase, aspartate aminotransferase). The relationships between the severity of COVID-19 in patients, the Insomnia Severity Index (ISI) score, and the Hospital Anxiety and Depression Scale (HADS) score were also investigated. Results: There were statistically significant associations between disease, smoking, and HADS-A scores (p = 0.011/0.020). The HADS-D score of patients with the disease was higher than in those without a past medical history (p = 0.008). The difference in C-reactive protein (CRP) between different lung infections, the HADS-A and HADS-D scores between different ages and ISI groups, and the correlation between the two scores were statistically significant. Conclusions: Anxiety and depression are associated with poor sleep quality, smoking, and past medical history in patients with COVID-19. Additionally, anxiety and depression were seen to coexist, and there was a positive correlation between them. Further, the inflammatory index CRP was significantly increased in bilateral lung infections.

4.
Environ Toxicol Pharmacol ; 71: 103206, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31212135

RESUMO

Pyruvic acid is important organic chemical intermediates that plays a role in cardiomyocyte pathophysiology and therapy. This study sought to explore the inotropic effects of pyruvic acid on the function of the isolated rat hearts and investigate its underlying mechanism. Pyruvic acid produced a greater negative inotropic effect compared to HCl and sodium pyruvate in a concentration-dependent pattern in the hearts. The role of low dose of pyruvic acid on heart function was regulated by pyruvic acid molecules and high dose pyruvic acid may be influenced by pyruvic acid molecules and pH. Kv channels may be involved in the pyruvic acid-induced negative inotropic effect. Finally, pyruvic acid markedly increased the level of LDH and CK and reduced the level of Ca2+Mg2+-ATPase and Na+K+-ATPase. These results suggest that pyruvic acid may modulate cardiac function at physiological or low doses but can cause damage to cardiomyocytes at high doses.


Assuntos
Coração/efeitos dos fármacos , Contração Miocárdica/efeitos dos fármacos , Miocárdio/metabolismo , Ácido Pirúvico/farmacologia , Ácido Pirúvico/toxicidade , Animais , Creatina Quinase/metabolismo , Relação Dose-Resposta a Droga , Coração/fisiopatologia , Técnicas In Vitro , L-Lactato Desidrogenase/metabolismo , Masculino , Perfusão , Bloqueadores dos Canais de Potássio/farmacologia , Canais de Potássio/metabolismo , Ratos Wistar
5.
Chemosphere ; 193: 60-73, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29126066

RESUMO

Formaldehyde (FA) has been linked to the detrimental cardiovascular effects. Here, we explored the effects and mechanisms of FA on rat aortas both in vivo and in vitro. The results presented that FA evidently lowered the blood pressures of rats. The expression levels of BKCa subunits α and ß1 and iNOS of the aortas were up-regulated by FA in vivo. However, FA markedly reduced the levels of Cav1.2 and Cav1.3, which are the subunits of L-Ca2+ channel. Furthermore, the contents of NO, cGMP and iNOS in the aortas were augmented by FA. To further confirm these findings, the mechanisms accredited to these effects were examined in vitro. The data showed that FA contracted the isolated aortic rings at low concentrations (<300 µM), while it relaxed the rings at high concentrations (>500 µM). The FA-induced vasoconstriction at low concentrations was blocked partly by an inhibitor of ACE. The relaxation caused by FA at high concentrations was attenuated by the inhibitors of NO-cGMP pathway, L-Ca2+ channel and BKCa channel, respectively. Similarly, the expression of iNOS was strongly enhanced by FA in vitro. The effects of FA on the aortic rings with endothelium were significantly greater than those on the rings without endothelium. Our results indicate that the vasoconstriction of FA at low concentrations might be partially pertinent to endothelin, and the FA-caused vasorelaxation at high concentrations is possibly associated with the NO-cGMP pathway, L-Ca2+ channel and BKCa channel. This study will improve our understanding of the pathogenic mechanisms for FA-related cardiovascular diseases.


Assuntos
Endotélio Vascular/efeitos dos fármacos , Formaldeído/toxicidade , Óxido Nítrico/metabolismo , Testes de Toxicidade , Animais , Aorta Torácica , GMP Cíclico , Formaldeído/metabolismo , Canais Iônicos , Masculino , Ratos , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos , Vasodilatação
6.
Regul Toxicol Pharmacol ; 72(3): 440-6, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26015265

RESUMO

Sodium metabisulfite (SMB) is used as an antioxidant and antimicrobial agent in a variety of drugs and foods. However, there are few reported studies about its side effects. This study is to investigate the SMB effects on the expression of ATP-sensitive K(+) (KATP) and L-type calcium (L-Ca(2+)) channels in rat hearts. The results show that the mRNA and protein levels of the KATP channel subunits Kir6.2 and SUR2A were increased by SMB; on the contrary, SMB at 520 mg/kg significantly decreased the expression of the L-Ca(2+) channel subunits Cav1.2 and Cav1.3. This suggests that SMB can activate the expression of KATP channel by increasing the mRNA and protein levels of Kir6.2 and SUR2A, while it inhibits the expression of L-Ca(2+) channels by decreasing the mRNA and protein levels of Cav1.2 and Cav1.3 in rat hearts. Therefore, the molecular mechanism of the SMB effect on rat hearts might be related to the increased expression of KATP channels and the decreased expression of L-Ca(2+) channels.


Assuntos
Canais de Cálcio Tipo L , Canais de Cálcio , Miocárdio/metabolismo , Canais de Potássio Corretores do Fluxo de Internalização , Sulfitos/toxicidade , Receptores de Sulfonilureias , Animais , Anti-Infecciosos/toxicidade , Antioxidantes/toxicidade , Canais de Cálcio/genética , Canais de Cálcio/metabolismo , Canais de Cálcio Tipo L/genética , Canais de Cálcio Tipo L/metabolismo , Coração/efeitos dos fármacos , Masculino , Miocárdio/patologia , Canais de Potássio Corretores do Fluxo de Internalização/genética , Canais de Potássio Corretores do Fluxo de Internalização/metabolismo , RNA Mensageiro/metabolismo , Ratos Wistar , Receptores de Sulfonilureias/genética , Receptores de Sulfonilureias/metabolismo
7.
Environ Toxicol Pharmacol ; 39(3): 1132-8, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25912853

RESUMO

Epidemiological studies have revealed an association between sulfur dioxide (SO2) exposure and cardiovascular diseases. This study is designed to investigate the SO2 effect on the expression of ATP-sensitive K(+) (KATP) channel and L-type calcium (L-Ca(2+)) channel in rat hearts. The results show that the mRNA and protein levels of the KATP channel subunits Kir6.2 and SUR2A of rat hearts in SO2 groups were higher than those in control group. SO2 at 14mg/m(3) significantly decreased the expression of the L-Ca(2+) channel subunits Cav1.2 and Cav1.3. This suggests that SO2 can activate the KATP channels by up-regulating the expression of Kir6.2 and SUR2A, while it inhibits the L-Ca(2+) channels by down-regulating the expression of Cav1.2 and Cav1.3 in rat hearts. The molecular mechanism of SO2-induced negative inotropic effect might be linked to the expression changes of these subunits, which may contribute to the pathogenesis of SO2-associated cardiovascular diseases.


Assuntos
Canais de Cálcio Tipo L/efeitos dos fármacos , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Coração/efeitos dos fármacos , Canais KATP/efeitos dos fármacos , Dióxido de Enxofre/toxicidade , Animais , Canais de Cálcio Tipo L/genética , Canais de Cálcio Tipo L/metabolismo , Regulação para Baixo , Inalação , Canais KATP/genética , Canais KATP/metabolismo , Masculino , Canais de Potássio Corretores do Fluxo de Internalização/efeitos dos fármacos , Canais de Potássio Corretores do Fluxo de Internalização/genética , Canais de Potássio Corretores do Fluxo de Internalização/metabolismo , Ratos , Ratos Wistar , Receptores de Sulfonilureias/efeitos dos fármacos , Receptores de Sulfonilureias/genética , Receptores de Sulfonilureias/metabolismo , Regulação para Cima
8.
J Hazard Mater ; 284: 151-62, 2015 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-25463229

RESUMO

Sodium metabisulfite (SMB) is most commonly used as the preservative in many food preparations and drugs. So far, few studies about its negative effects were reported. The purpose of this study was to investigate the effect of SMB on the expression of big-conductance Ca(2+)-activated K(+) (BKCa), ATP-sensitive K(+) (KATP), and L-type calcium (L-Ca(2+)) channels in rat aorta in vivo and in vitro. The results showed that the mRNA and protein levels of the BKCa channel subunits α and ß1 of aorta in rats were increased by SMB in vivo and in vitro. Similarly, the expression of the KATP channel subunits Kir6.1, Kir6.2, and SUR2B were increased by SMB. However, SMB at the highest concentration significantly decreased the expression of the L-Ca(2+) channel subunits Cav1.2 and Cav1.3. These results suggest that SMB can activate BKCa and KATP channels by increasing the expression of α, ß1, and Kir6.1, Kir6.2, SUR2B respectively, while also inhibit L-Ca(2+) channels by decreasing the expression of Cav1.2 and Cav1.3 of aorta in rats. The molecular mechanism of SMB-induced vasorelaxant effect might be related to the expression changes of BKCa, KATP, and L-Ca(2+) channels subunits. Further work is needed to determine the relative contribution of each channel in SMB-mediated vasorelaxant effect.


Assuntos
Aorta/efeitos dos fármacos , Aorta/patologia , Sulfitos/química , Trifosfato de Adenosina/metabolismo , Animais , Aorta/metabolismo , Broncoconstritores/química , Canais de Cálcio/metabolismo , Canais de Cálcio Tipo L/metabolismo , Relação Dose-Resposta a Droga , Regulação da Expressão Gênica/efeitos dos fármacos , Canais KATP/metabolismo , Masculino , Mutação , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Software , Vasodilatação/efeitos dos fármacos
9.
Eur J Pharmacol ; 742: 31-41, 2014 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-25192964

RESUMO

Epidemiological investigations have revealed that sulfur dioxide (SO2) exposure is linked to cardiovascular diseases. Our previous study indicated that the vasorelaxant effect of SO2 might be partly related to ATP-sensitive K(+) (KATP), big-conductance Ca(2+)-activated K(+) (BKCa) and L-type calcium (L-Ca(2+)) channels. The present study was designed to further investigate the effects of gaseous SO2 and its derivatives on the gene and protein expression of these channels in the rat aortas in vitro. The results showed that the mRNA and protein levels of the KATP channel subunits Kir6.1, Kir6.2 and SUR2B of the rat aortas in SO2 and its derivatives groups were higher than those in control group. Similarly, the expression of the BKCa channel subunits α and ß1 was increased by SO2 and its derivatives. However, SO2 and its derivatives at 1500µM significantly decreased the expression of the L-Ca(2+) channel subunits Cav1.2 and Cav1.3. Histological examination of the rat aorta tissues showed moderate injury of tunica media induced by SO2 and its derivatives at 1500µM. These results suggest that SO2 and its derivatives can activate the KATP and BKCa channels by increasing the expression of Kir6.1, Kir6.2, SUR2B and α, ß1, respectively, while also inhibiting the L-Ca(2+) channels by decreasing the expression of Cav1.2 and Cav1.3 of the rat aortas. The molecular mechanism of the vasorelaxant effect of SO2 and its derivatives might be related to the expression changes of KATP, BKCa and L-Ca(2+) channel subunits, which may play a role in the pathogenesis of SO2-associated cardiovascular diseases.


Assuntos
Aorta/efeitos dos fármacos , Aorta/metabolismo , Canais de Cálcio Tipo L/genética , Canais de Cálcio Tipo L/metabolismo , Canais KATP/genética , Canais KATP/metabolismo , Subunidades alfa do Canal de Potássio Ativado por Cálcio de Condutância Alta/genética , Subunidades alfa do Canal de Potássio Ativado por Cálcio de Condutância Alta/metabolismo , Dióxido de Enxofre/toxicidade , Poluentes Atmosféricos/toxicidade , Animais , Aorta/patologia , Expressão Gênica/efeitos dos fármacos , Técnicas In Vitro , Masculino , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Vasodilatação/efeitos dos fármacos
10.
Chemosphere ; 112: 296-304, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25048919

RESUMO

BACKGROUND: Exposure to sulfur dioxide (SO2) increases asthma risk. Inflammatory and immune responses are typical in asthma disease. The exact effect of SO2 on modulation of the inflammatory and immune responses in asthmatic rats remains unclear. OBJECTIVES: Here we sought to investigate the molecular mechanisms underlying the NF-κB inflammatory pathway and the Th1/Th2 imbalance in asthmatic rats exposed to SO2. METHODS: Male Wistar rats were challenged by ovalbumin (OVA) or SO2 alone or together, and then mRNA and protein levels of some inflammatory and immune genes were measured. NF-κB nuclear translocation was analyzed. Bronchoalveolar lavage (BAL), inflammatory cell counts and histopathologic examination were performed. RESULTS: (1) OVA plus SO2 induced abnormal pathological changes and inflammatory responses in lung relative to exposure to OVA alone; (2) showing NF-κB nuclear translocation and activation through up-regulating IKKß mRNA and protein expression and down-regulating IκBα expression in the presence of OVA or OVA plus SO2; (3) OVA plus SO2 significantly raised TNF-α and IL-6 levels in BALF compared with the OVA group; (4) SO2 markedly elevated IL-4 levels and decreased IFN-γ levels in BALF in the asthmatic rats, stimulating IgE generation which was closely related to inhibiting the expression of Foxp3, a specific marker of regulatory T cells. CONCLUSIONS: SO2 affects the airway inflammatory and immune responses of the asthmatic rats and enhances the susceptibility to OVA by aggravating inflammatory responses in lungs, up-regulating pro-inflammatory cytokine expression, and causing the Th1/Th2 imbalance, which might contribute to the increased risk of asthma disease.


Assuntos
Asma/imunologia , Poluentes Ambientais/farmacologia , Dióxido de Enxofre/farmacologia , Animais , Asma/sangue , Asma/genética , Asma/metabolismo , Citocinas/genética , Citocinas/metabolismo , Interações Medicamentosas , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/imunologia , Imunoglobulina E/sangue , Inflamação/sangue , Inflamação/genética , Inflamação/imunologia , Inflamação/metabolismo , Pulmão/efeitos dos fármacos , Pulmão/imunologia , Pulmão/metabolismo , Masculino , Ovalbumina/imunologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar
11.
Chemosphere ; 89(5): 579-84, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22763331

RESUMO

To study the biological role of bisulfite on vascular contractility and its underlying cellular and molecular mechanisms, to explore whether bisulfite can be used as a sulfur dioxide (SO(2)) donor in the biological experiments, the vasorelaxant effects of sodium bisulfite and sodium sulfite on isolated rat thoracic aortic rings were compared; and the signal transduction pathways and the ion channels involved in the vascular effects of bisulfite were investigated. The results show that: (1) Sodium bisulfite relaxed rat thoracic aortic rings in a concentration-dependent manner (from 100 to 4000 µM); however, sodium sulfite at 500 and 1000 µM caused vasoconstriction, and only at higher concentrations (from 2000 to 4000 µM) it caused vasorelaxation in a concentration-dependent manner. (2) The vasorelaxation caused by the bisulfite at low concentrations (≤500 µM) was endothelium-dependent, but at high concentrations (≥1000 µM) it was endothelium-independent. (3) The vasorelaxation by the bisulfite at the low concentrations was partially mediated by the cGMP pathway and the vasorelaxation was related to big-conductance Ca(2+)-activated K(+) (BK(Ca)) channel, but not due to prostaglandin, protein kinase C (PKC) and cAMP pathways. (4) The vasorelaxation by the bisulfite at high concentrations was partially inhibited by tetraethylammonium (TEA) and glibenclamide, suggesting that the vasorelaxation was related to ATP-sensitive K(+) channel (K(ATP)) and L-type calcium-channel. These results led to the conclusion that bisulfite (HSO(3)(-)) might be a vasoactive factor and sodium bisulfite can be used as a SO(2) donor for the study of SO(2) biology.


Assuntos
Sulfitos/metabolismo , Sulfitos/farmacologia , Dióxido de Enxofre/metabolismo , Vasodilatação/efeitos dos fármacos , Vasodilatadores/metabolismo , Vasodilatadores/farmacologia , Absorção , Animais , Canais de Cálcio Tipo L/metabolismo , GMP Cíclico/metabolismo , Relação Dose-Resposta a Droga , Endotélio Vascular/citologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Endotélio Vascular/fisiologia , Técnicas In Vitro , Masculino , Canais de Potássio/metabolismo , Ratos , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos , Sulfitos/química , Dióxido de Enxofre/química , Vasodilatadores/química , Água/química
12.
Food Chem Toxicol ; 50(9): 3114-9, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22727858

RESUMO

Sodium metabisulfite (SMB) is most commonly used as a food additives, however few study was performed on the vasodilator effect of SMB. In the present paper, the vasodilator effects of SMB and roles of Ca(2+) and K(+) channels as well as the cGMP pathway on isolated rat aortic rings were studied. The results show that: (1) SMB could relax isolated aortic rings precontracted by norepinephrine in a concentration-dependent manner. The maximal endothelium-dependent vasorelaxation was approximately 20% whereas that not depending on the presence of the endothelium was more than 90%. (2) The vasorelaxant effects induced by 50 or 200 µM SMB were partially inhibited by iberiotoxin, NS-2028 or l-NNA. The vasorelaxation of 1000 µM SMB was partially inhibited by nifedipine or glibenclamide. The SMB induced vasorelaxation was partially inhibited by tetraethylammonium. These results led to the conclusions that the vasorelaxation of SMB at low concentrations (<400 µM) was endothelium-dependent and mediated by the cGMP pathway and BK(Ca) channel, but at high concentrations (>500 µM) was endothelium-independent and mediated by K(ATP) channel and L-type Ca(2+) channel. The maximal allowable concentration from China and the acceptable daily intake level from WHO of SMB as a food additive should be revised.


Assuntos
Aorta/efeitos dos fármacos , Canais Iônicos/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sulfitos/farmacologia , Animais , Aorta/metabolismo , Aorta/fisiologia , GMP Cíclico/metabolismo , Técnicas In Vitro , Ratos
13.
Environ Toxicol ; 27(3): 175-84, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20607818

RESUMO

Epidemiological investigations have revealed that sulfur dioxide (SO(2) ) exposure is linked to cardiovascular diseases. The present study was designed to investigate the negative inotropic effects of gaseous SO(2) and its derivatives in the isolated perfused rat heart and the possible mechanisms involved in their effects. The results showed that both SO(2) and SO(2) derivatives elicited a negative inotropic effect in a dose-dependent manner, and SO(2) produced a higher negative effect than SO(2) derivatives. The mechanism of SO(2) -induced negative inotropic effects at low concentrations was different from that at high concentrations. At low concentrations, the mechanism of SO(2) -induced negative inotropic effects might occur through promoting the activities of protein kinase C (PKC), cycloxygenase, and cGMP, while the mechanism of SO(2) derivatives-induced effects might be related to the opening of ATP-sensitive K(+) (K(ATP) ) channel and the inhibition of Ca(2+) influx via L-type calcium-channel. At high concentrations, the mechanisms of SO(2) and SO(2) derivatives-induced negative inotropic effects were similar, which might be related to the K(ATP) channel and L-type calcium-channel as well as the possible alterations in PKC, cycloxygenase, and cGMP. Further work is needed to determine the relative contribution of each pathway in SO(2) -mediated inotropic effect.


Assuntos
Poluentes Atmosféricos/toxicidade , Coração/efeitos dos fármacos , Miocárdio/metabolismo , Dióxido de Enxofre/toxicidade , Poluentes Atmosféricos/metabolismo , Animais , Canais de Cálcio/metabolismo , Canais de Cálcio Tipo L/metabolismo , Guanilato Ciclase/metabolismo , Coração/fisiologia , Técnicas In Vitro , Masculino , Contração Miocárdica/efeitos dos fármacos , Óxido Nítrico Sintase/metabolismo , Canais de Potássio/metabolismo , Proteína Quinase C/antagonistas & inibidores , Proteína Quinase C/metabolismo , Ratos , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos , Dióxido de Enxofre/metabolismo
14.
Sheng Li Xue Bao ; 63(6): 593-600, 2011 Dec 25.
Artigo em Chinês | MEDLINE | ID: mdl-22193456

RESUMO

Based on our studies for more than 20 years, we review the recent advances in sulfur dioxide (SO2) biology. Three sections are involved: (1) The studies on SO2 toxicological effects and its underlying mechanisms; (2) The new investigations on SO2 donor and physiological role of SO2 as a new type-gas transmitter; (3) The observations on pathophysiologic roles of SO2.


Assuntos
Dióxido de Enxofre/metabolismo , Dióxido de Enxofre/toxicidade , Animais , Humanos , Fenômenos Fisiológicos
15.
J Exp Biol ; 214(Pt 23): 4048-54, 2011 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-22071197

RESUMO

Ammonia (NH(3)) is a common exogenous gas in the atmosphere, as well as an endogenous chemical produced by amino acid catabolism and other pathways in vivo. Physiological and pathophysiological roles of NH(3) in the nervous system have been studied. Recently, endogenous NH(3) has been suggested to be a gas transmitter. However, so far the role of NH(3) in cardiovascular functions has not been reported. The present study was designed to investigate the inotropic effects of NH(3) on isolated perfused rat hearts and the possible mechanisms involved in these effects. The results showed that NH(3) had a positive inotropic effect in a concentration-dependent manner and produced a higher positive effect than NaOH and NH(4)Cl. At low concentrations, the effect of NH(3) on cardiac function was caused by NH(3) molecules; at high concentrations, the effect of NH(3) on hearts may be partly correlated with a change of pH value, but was mainly caused by NH(3) molecules. The mechanisms involved in the NH(3)-induced positive inotropic effect may be related to the ATP-sensitive K(+) (K(ATP)) channel and the nitric oxide (NO)-cyclic GMP (cGMP) signaling pathway. In addition, at a concentration of 1.5 mmol l(-1), NH(3) significantly increased the activity of creatine kinase (CK) and lactate dehydrogenase (LDH) in the coronary perfusate and decreased the activity of Na(+),K(+)-ATPase and Ca(2+),Mg(2+)-ATPase in the hearts. These results indicate that NH(3) at physiological or low concentrations may play a modulatory role in heart function, but at high concentrations had a damaging effect on isolated rat hearts.


Assuntos
Amônia/farmacologia , Cardiotônicos/farmacologia , Coração/efeitos dos fármacos , Coração/fisiologia , Contração Miocárdica/efeitos dos fármacos , Adenosina Trifosfatases/metabolismo , Cloreto de Amônio/farmacologia , Animais , Creatina Quinase/metabolismo , GMP Cíclico/metabolismo , Guanilato Ciclase/metabolismo , Ventrículos do Coração/efeitos dos fármacos , Concentração de Íons de Hidrogênio/efeitos dos fármacos , Técnicas In Vitro , Canais KATP/metabolismo , L-Lactato Desidrogenase/metabolismo , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase/metabolismo , Oxidiazóis/farmacologia , Oxazinas/farmacologia , Perfusão , Pressão , Ratos , Transdução de Sinais/efeitos dos fármacos , Canais de Potássio Ativados por Cálcio de Condutância Baixa/metabolismo , Hidróxido de Sódio/farmacologia , Solubilidade/efeitos dos fármacos
16.
Hum Exp Toxicol ; 30(10): 1521-8, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21148201

RESUMO

A positive association of lead exposure with clinical cardiovascular outcomes has been identified. Epigallocatechin-3-gallate (EGCG) is one of the active polyphenols in green tea, it has not been reported as an antioxidant against lead toxicity. This study was carried out to investigate whether EGCG could protect the ventricular myocytes of rats against lead-induced oxidative damage. Isolated ventricular myocytes were exposed to lead and/or EGCG, then activities of superoxide dismutase (SOD), catalase (CAT), and malondialdehyde (MDA) and the levels of hydroxyl radical (OH(·)), hydrogen peroxide (H(2)O(2)), and superoxide anion (O(2) (·-)) were measured. The results showed that lead induced a significant decrease of SOD and CAT activities, while the levels of MDA increased significantly. Increases in intracellular OH(·), O(2) (·-), and H(2)O(2) were found as well. These processes were concentration-dependent and statistically significant different when compared to 2.0 µM lead exposure. The activity of SOD and CAT increased while the levels of MDA and reactive oxygen species (ROS) decreased after treatment with EGCG. While there were progressive benefits with increasing EGCG concentrations, there was no statistical significance at a 30 µg/mL dose when compared with the control. These results will provide more evidence for lead toxicity to tissue, cell, and biological macromolecule.


Assuntos
Antioxidantes/farmacologia , Catequina/análogos & derivados , Chumbo/toxicidade , Miócitos Cardíacos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Animais , Catalase/metabolismo , Catequina/farmacologia , Técnicas In Vitro , Peroxidação de Lipídeos/efeitos dos fármacos , Malondialdeído/metabolismo , Miócitos Cardíacos/metabolismo , Ratos , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo
17.
Eur J Pharmacol ; 645(1-3): 143-50, 2010 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-20674563

RESUMO

Sulfur dioxide (SO(2)) is a common gaseous pollutant. It is also, however, endogenously generated from sulfur-containing amino acids. Recent studies have demonstrated that rat blood pressure can be lowered by SO(2)-exposure in vivo and that vasodilation caused by SO(2) at low concentrations (<450 microM) is endothelium-dependent in rat aorta. However, effects of SO(2) on nitric oxide synthase (NOS) and nitric oxide (NO) production have not been previously studied in rat aorta. The objective of the present study is to assess the effects of acute (10 min) and prolonged (2h) stimulation with different concentrations of SO(2) on NO/cGMP pathway in isolated rat aorta. The results show that: (1) the acute and prolonged pretreatments with SO(2) produced an inhibition of vasoconstrictions induced by norepinephrine. (2) SO(2) potentiated activity of endothelial nitric oxide synthase (eNOS), but not of induced NOS (iNOS). (3) SO(2) could increase expression of eNOS gene on the transcription and translation levels in rat aorta. (4) SO(2) enhanced NO formation in aortic tissue. (5) The level of cGMP in rat aorta was increased by SO(2) and no change of cAMP. These findings led to the conclusion: there were acute and prolonged effects of SO(2) on the NO/cGMP signalling pathway; and SO(2) could upregulate the eNOS-NO-cGMP pathway and at least partly by which the SO(2) might cause vasodilation and inhibition to vasoconstriction.


Assuntos
Aorta/metabolismo , Óxido Nítrico/biossíntese , Dióxido de Enxofre/metabolismo , Animais , Aorta/efeitos dos fármacos , GMP Cíclico/metabolismo , Técnicas In Vitro , Masculino , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Óxido Nítrico/genética , Óxido Nítrico Sintase/biossíntese , Óxido Nítrico Sintase/genética , Óxido Nítrico Sintase Tipo II/biossíntese , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo III/biossíntese , Óxido Nítrico Sintase Tipo III/genética , Ratos , Ratos Wistar , Transdução de Sinais , Dióxido de Enxofre/farmacologia , Fatores de Tempo , Regulação para Cima , Vasoconstrição , Vasodilatação/efeitos dos fármacos
18.
Cardiovasc Toxicol ; 10(3): 166-73, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20473584

RESUMO

Sulfite (bisulfite/sulfite) can affect voltage-gated sodium (Na(+)) channels (VGSC) in a concentration-dependent manner in isolated rat ventricular myocytes. In this study, the effect of epigallocatechin-3-gallate (EGCG) on VGSC in isolated ventricular myocytes was studied. Ventricular myocytes were exposed to 10 microM bisulfite/sulfite for 10 min, and EGCG was then administered in different concentrations (10, 30, 50 microg ml(-1)). Decreased activity of superoxide dismutase, catalase (CAT) and glutathione peroxidase (GPx) was observed after bisulfite/sulfite exposure, with significant increase in Na(+) currents (I (Na)) and alterations in half-activation voltage and half-inactivation voltage. Intracellular reactive oxygen species (ROS) such as hydrogen peroxide (H(2)O(2)), hydroxyl (OH(.)), and superoxide anion (O (2) (.-) ) were increased. After EGCG treatment, activity of the aforementioned enzymes increased while the ROS level decreased. The effects progressed with increasing amounts of EGCG, up to a level similar to blank control at the dose of 50 microg ml(-1) EGCG, EGCG also reduced the I (Na) and reversed the alterations in half-activation voltage and half-inactivation voltage. In conclusion, EGCG could protect Na(+) channels in rat ventricular myocytes against the oxidative damage induced by sulfite as a scavenger of the ROS.


Assuntos
Catequina/análogos & derivados , Miócitos Cardíacos/efeitos dos fármacos , Canais de Sódio/efeitos dos fármacos , Sulfitos/antagonistas & inibidores , Sulfitos/toxicidade , Animais , Catalase/metabolismo , Catequina/farmacologia , Separação Celular , Eletrofisiologia , Glutationa Peroxidase/metabolismo , Peróxido de Hidrogênio/metabolismo , Radical Hidroxila/metabolismo , Miócitos Cardíacos/enzimologia , Estresse Oxidativo/efeitos dos fármacos , Técnicas de Patch-Clamp , Ratos , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo , Superóxidos/metabolismo
19.
Inhal Toxicol ; 22(4): 322-9, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20064080

RESUMO

Concurrent exposure to SO(2) and benzo(a)pyrene (B(a)P) resulted in an increased incidence of lung tumors in rodents compared to exposure to B(a)P alone. A synergistic effect on the expression of c-fos and c-jun between SO(2) and B(a)P was observed in lungs after SO(2) and B(a)P exposure. However, tumorigenesis occurs by multiple events that may involve the activation of more than one oncogene, as well as the functional loss of the tumor suppressor gene. In order to further investigate the interactions between SO(2) and B(a)P, male Wistar rats were exposed via intratracheal instillation of B(a)P (3 mg) or SO(2) (56 mg/m(3)) inhalation, alone or together. The mRNA and protein levels of oncogenes (c-myc and H-ras) and tumor suppressor genes (p53, p16, and Rb) were analyzed in lungs by real-time reverse transcriptase-polymerase chain reaction (RT-PCR) and Western blot, respectively. The results showed that all treatments increased mRNA and protein expression levels of c-myc, H-ras, and p53, and reduced expression levels of p16 and Rb. In general, the combination of SO(2) and B(a)P was more effective in influencing these expression levels than either agent alone, except for H-ras expression. These findings indicate that multiple cell cycle regulatory proteins play key roles in the toxicity of SO(2) and B(a)P. It might involve the activation of c-fos, c-jun, c-myc, and p53. And the p16-Rb pathway might also participate in the progress. Elucidating the expression patterns of those factors after SO(2) and B(a)P exposure may be critical to understanding the mechanisms of SO(2) cocarcinogenesis and helpful for therapeutic intervention.


Assuntos
Benzo(a)pireno/toxicidade , Poluentes Ambientais/toxicidade , Expressão Gênica/efeitos dos fármacos , Genes Supressores de Tumor/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Oncogenes/genética , Dióxido de Enxofre/toxicidade , Administração por Inalação , Animais , Benzo(a)pireno/administração & dosagem , Western Blotting , DNA Complementar/biossíntese , DNA Complementar/isolamento & purificação , Genes do Retinoblastoma/efeitos dos fármacos , Genes p16/efeitos dos fármacos , Genes p53/efeitos dos fármacos , Genes ras/efeitos dos fármacos , Masculino , RNA/biossíntese , RNA/isolamento & purificação , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Dióxido de Enxofre/administração & dosagem
20.
Environ Toxicol ; 25(3): 272-83, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19434695

RESUMO

Sulfur dioxide (SO(2)) is a ubiquitous air pollutant that is present in low concentrations in the urban air, and in higher concentrations in the working environment. In the present study, male Wistar rats were housed in exposure chambers and treated with 14.00 +/- 1.01, 28.00 +/- 1.77 and 56.00 +/- 3.44 mg m(-3) SO(2) for 6 h/day for 7 days, while control group was exposed to filtered air in the same condition. The mRNA and protein levels of proto-oncogenes (c-fos, c-jun, c-myc, and Ki-ras) and tumor suppressor genes (p53, Rb, and p16) were analyzed in lungs using a real-time reverse transcription-polymerase chain reaction (real-time RT-PCR) assay and Western blot analysis. The results showed that mRNA and protein levels of c-fos, c-jun, c-myc, Ki-ras, and p53 in lungs were increased in a dose-dependent manner, while mRNA and protein levels of Rb and p16 were decreased in lungs of rats after SO(2) inhalation. These results lead to a conclusion that SO(2) exposure could activate expressions of proto-oncogenes and suppress expressions of tumor suppressor genes, which might relate to the molecular mechanism of cocarcinogenic properties and potential carcinogenic effects of SO(2). According to previous studies, the results also indicated that promoter genes of apoptosis and tumor suppressor genes could produce apoptotic signals to antagonize the growth signals that arise from oncogenes. Understanding its molecular controls will benefit development of treatments for many diseases.


Assuntos
Poluentes Atmosféricos/toxicidade , Expressão Gênica/efeitos dos fármacos , Genes Supressores de Tumor , Exposição por Inalação/efeitos adversos , Pulmão/efeitos dos fármacos , Proto-Oncogenes , Dióxido de Enxofre/toxicidade , Animais , Western Blotting , Peso Corporal/efeitos dos fármacos , Relação Dose-Resposta a Droga , Eletroforese em Gel de Poliacrilamida , Pulmão/metabolismo , Masculino , Proteínas Proto-Oncogênicas/biossíntese , Proteínas Proto-Oncogênicas/genética , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteínas Supressoras de Tumor/biossíntese , Proteínas Supressoras de Tumor/genética
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