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1.
Pathol Res Pract ; 252: 154920, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37948998

RESUMO

Clinical data indicates that SARS-CoV-2 infection-induced respiratory failure is a fatal condition for severe COVID-19 patients. However, the pathological alterations of different types of respiratory failure remained unknown for severe COVID-19 patients. This study aims to evaluate whether there are differences in the performance of various types of respiratory failure in severe COVID-19 patients and investigate the pathological basis for these differences. The lung tissue sections of severe COVID-19 patients were assessed for the degree of injury and immune responses. Transcriptome data were used to analyze the molecular basis in severe COVID-19 patients. Severe COVID-19 patients with combined oxygenation and ventilatory failure presented more severe pulmonary fibrosis, airway obstruction, and prolonged disease course. The number of M2 macrophages increased with the degree of fibrosis in patients, suggesting that it may be closely related to the development of pulmonary fibrosis. The co-existence of pro-inflammatory and anti-inflammatory cytokines in the pulmonary environment could also participate in the progression of pulmonary fibrosis. Furthermore, the increased apoptosis in the lungs of COVID-19 patients with severe pulmonary fibrosis may represent a critical factor linking sustained inflammatory responses to fibrosis. Our findings indicate that during the extended phase of COVID-19, antifibrotic and antiapoptotic treatments should be considered in conjunction with the progression of the disease.


Assuntos
COVID-19 , Fibrose Pulmonar , Insuficiência Respiratória , Humanos , COVID-19/complicações , COVID-19/patologia , Fibrose Pulmonar/patologia , Autopsia , SARS-CoV-2 , Pulmão/patologia , Macrófagos/patologia , Insuficiência Respiratória/patologia , Apoptose
2.
Medicine (Baltimore) ; 102(41): e35552, 2023 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-37832074

RESUMO

Kaposi sarcoma (KS) is the most common cancer in patients with human immunodeficiency virus/acquired immunodeficiency syndrome (AIDS). In 1994, Chang and Moore discovered Kaposi sarcoma associated herpesvirus for the first time in KS lesions in AIDS patients. KS is a low-grade mesenchymal neoplasm of blood and lymphatic vessels that primarily affects the skin, although the disease may become disseminated to the lymphatic system, lungs, airways, or abdominal viscera. In this research, clinical characteristics and treatment of patients of Kaposi sarcoma were retrospectively analyzed in Hotan District, Xinjiang China. We look into the clinical traits, prognosis, and therapy of Kaposi sarcoma. From May 2017 to August 2022, 32 patients were treated in the People's Hospital of Hotan District, Xinjiang Uygur Autonomous Region, China. Twenty-two of these were classic Kaposi sarcomas (cKS), and 10 of these were Kaposi sarcomas linked to AIDS (AIDS-KS). The majority of KS patients were Uyghur. In terms of age at onset, AIDS-KS patients were younger than cKS patients. cKS and AIDS-KS are most frequently manifested in the feet and lower limbs. Ten patients with AIDS-KS have treated with combination antiretroviral therapy (combination antiretroviral therapy) combination chemotherapy, 5 of 10 patients had a complete response, 2 patients achieved partial response, the overall effective rate was 70%, and CD4 + T cells were greater than before. For cKS and AIDS-KS, the median overall survival was 56 and 50.8 months, respectively (P > .05). As a result, antiviral combination chemotherapy can also improve the prognosis of AIDS-KS patients.


Assuntos
Síndrome da Imunodeficiência Adquirida , Herpesvirus Humano 8 , Sarcoma de Kaposi , Neoplasias Cutâneas , Humanos , Sarcoma de Kaposi/tratamento farmacológico , Sarcoma de Kaposi/epidemiologia , Sarcoma de Kaposi/patologia , Estudos Retrospectivos , Síndrome da Imunodeficiência Adquirida/complicações , Síndrome da Imunodeficiência Adquirida/epidemiologia , Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Neoplasias Cutâneas/patologia
3.
Int J Clin Pract ; 2022: 2794408, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36545346

RESUMO

Objective: This study aimed to investigate the fear of cancer recurrence (FCR) in breast cancer patients and develop a structural equation model of influencing factors to help formulate clinical intervention strategies. Methods: A convenience sample of 325 patients was surveyed using a general and disease-related data questionnaire, which combined the Fear of Progression Questionnaire-Short Form, Mishel Uncertainty in Illness Scale, Perceived Social Support Scale, and Medical Coping Modes Questionnaire. Results: The total score of FCR in breast cancer patients was 35.06 ± 10.83, and 53.8% of patients reached the clinical level. The structural equation model demonstrated that illness uncertainty had a direct positive impact on FCR (ß = 0.275, p < 0.05), and it could have an indirect impact through social support and resignation coping methods (ß = 0.254, p < 0.05). Conclusion: The fear of cancer recurrence in breast cancer patients needs further understanding. Medical staff can reduce or buffer FCR in breast cancer patients by strengthening positive influences, such as social support, or weakening negative influences, such as illness uncertainty and resignation coping.


Assuntos
Neoplasias da Mama , Humanos , Feminino , Estudos Transversais , Análise de Classes Latentes , Recidiva Local de Neoplasia , Medo
4.
Cancer Lett ; 533: 215605, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35219772

RESUMO

Although the tumorigenic potential of glioma stem cells (GSCs) is associated with multiple molecular alterations, the gene amplification status of GSCs has not been elucidated. Overexpression of HomeoboxA5 (HOXA5) is associated with increased glioma malignancy. In this study, we identify the gene amplification and protein overexpression of HOXA5 in GSCs and its function in regulating GSC maintenance and the downstream transcriptional effector, to explore the significance of HOXA5 amplification/overexpression for GSC identification and prognostic determination. The HOXA5 gene is significantly amplified in glioblastoma (GBM) and is an independent prognostic factor for predicting worse patient outcomes. Specifically, HOXA5 gene amplification and the resultant protein overexpression are correlated with increased proportions of GSCs and enhanced self-renewal/invasiveness of these cells. Disruption of HOXA5 expression impairs GSC survival and GBM tumor propagation. Mechanistically, HOXA5 directly binds to the promoter region of protein tyrosine phosphatase receptor type Z1 (PTPRZ1), thereby upregulating this gene for GSC maintenance. Suppression of PTPRZ1 largely compromises the pro-tumoral effect of HOXA5 on GSCs. In summary, HOXA5 amplification serves as a genetic biomarker for predicting worse GBM outcome, by enhancing PTPRZ1-mediated GSC survival.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Glioma , Neoplasias Encefálicas/patologia , Carcinogênese/metabolismo , Proteínas de Transporte/metabolismo , Linhagem Celular Tumoral , Glioblastoma/patologia , Glioma/patologia , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Humanos , Células-Tronco Neoplásicas/metabolismo , Monoéster Fosfórico Hidrolases/metabolismo , Proteínas Tirosina Fosfatases Classe 5 Semelhantes a Receptores/metabolismo
5.
Cell Res ; 31(10): 1072-1087, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34239070

RESUMO

Glioblastoma (GBM) is a prevalent and highly lethal form of glioma, with rapid tumor progression and frequent recurrence. Excessive outgrowth of pericytes in GBM governs the ecology of the perivascular niche, but their function in mediating chemoresistance has not been fully explored. Herein, we uncovered that pericytes potentiate DNA damage repair (DDR) in GBM cells residing in the perivascular niche, which induces temozolomide (TMZ) chemoresistance. We found that increased pericyte proportion correlates with accelerated tumor recurrence and worse prognosis. Genetic depletion of pericytes in GBM xenografts enhances TMZ-induced cytotoxicity and prolongs survival of tumor-bearing mice. Mechanistically, C-C motif chemokine ligand 5 (CCL5) secreted by pericytes activates C-C motif chemokine receptor 5 (CCR5) on GBM cells to enable DNA-dependent protein kinase catalytic subunit (DNA-PKcs)-mediated DDR upon TMZ treatment. Disrupting CCL5-CCR5 paracrine signaling through the brain-penetrable CCR5 antagonist maraviroc (MVC) potently inhibits pericyte-promoted DDR and effectively improves the chemotherapeutic efficacy of TMZ. GBM patient-derived xenografts with high CCL5 expression benefit from combined treatment with TMZ and MVC. Our study reveals the role of pericytes as an extrinsic stimulator potentiating DDR signaling in GBM cells and suggests that targeting CCL5-CCR5 signaling could be an effective therapeutic strategy to improve chemotherapeutic efficacy against GBM.


Assuntos
Glioblastoma , Animais , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos , Glioblastoma/tratamento farmacológico , Camundongos , Comunicação Parácrina , Pericitos , Temozolomida/farmacologia , Temozolomida/uso terapêutico , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Theriogenology ; 164: 58-64, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33550092

RESUMO

Mammalian sperm is highly susceptible to reactive oxygen species (ROS) during the cryopreservation process. Astaxanthin (AST), a red pigment of the carotenoid family, is recognized as having a variety of beneficial biological activities and effects, including antioxidant, anticancer, anti-diabetic, and anti-inflammatory. The present study aimed to investigate whether the presence of AST protected boar sperm from ROS stress during cryopreservation. Boar sperm was diluted with a freezing medium supplemented with different concentrations of AST (0, 0.5, 1, 2, or 5 µM). The addition of AST, especially at a concentration of 2 µM, exerted positive effects on post-thaw sperm motility parameters. Meanwhile, sperm plasma membrane integrity and acrosome integrity of post-thaw sperm were significantly increased, while lipid peroxidation was inhibited in response to 2 µM AST treatment. Interestingly, compared to the control, supplementation with 2 µM AST increased unsaturated fatty acids (UFAs) levels and decreased saturated fatty acids (SFAs) content in post-thaw sperm, leading to a decreased ratio of SFAs/UFAs in the AST group. In conclusion, the addition of AST to freezing extenders inhibited lipid peroxidation and regulated fatty acid composition of the sperm membrane, improved post-thaw sperm quality, and had no adverse effect on boar sperm in vitro fertilization (IVF) capacity and potential for embryonic development. Our data provide a novel insight into understanding the mechanisms of AST concerning protecting boar sperm quality against ROS damage during cryopreservation.


Assuntos
Preservação do Sêmen , Animais , Membrana Celular , Criopreservação/veterinária , Crioprotetores/farmacologia , Fertilidade , Masculino , Preservação do Sêmen/veterinária , Motilidade dos Espermatozoides , Espermatozoides , Suínos , Xantofilas
7.
Reprod Domest Anim ; 54(8): 1069-1077, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31099063

RESUMO

Spermatozoa are highly specialized cells, and energy metabolism plays an important role in modulating sperm viability and function. Rosiglitazone is an antidiabetic drug in the thiazolidinedione class that regulates metabolic flexibility and glucose uptake in various cell types, but its effects on boar sperm metabolism are unknown. In this study, we investigated the potential effect of rosiglitazone against time-dependent deterioration of boar spermatozoa during liquid preservation at 17°C. Freshly ejaculated semen was diluted with Beltsville Thawing Solution (BTS) containing different concentrations of rosiglitazone, and the motility, membrane and acrosome integrity of sperm were detected. Besides, we measured glucose uptake capacity, l-lactate production level, mitochondrial membrane potential, adenosine triphosphate (ATP) content and mitochondrial reactive oxygen species (mROS) production of sperm after boar semen had been incubated with or without rosiglitazone, iodoacetate (glycolysis inhibitor) and rotenone (electron transport chain inhibitor) for 5 days. The addition of rosiglitazone significantly enhanced sperm quality and had a strong protective effect on the sperm membrane and acrosome integrity during storage. BTS containing 50 µM rosiglitazone maintained the total motility of liquid-preserved sperm above 60% for 7 days. Rosiglitazone improved sperm quality by regulating energy metabolism manner of preserved sperm, protected the sperm mitochondrial membrane potential, enhanced sperm ATP production and in the meanwhile reduced mROS through enhancing glycolysis but not oxidative phosphorylation. The data suggested the practical feasibility of using rosiglitazone for improving boar spermatozoa quality during semen preservation.


Assuntos
Hipoglicemiantes/farmacologia , Rosiglitazona/farmacologia , Preservação do Sêmen/veterinária , Espermatozoides/efeitos dos fármacos , Espermatozoides/fisiologia , Suínos , Animais , Crioprotetores/farmacologia , Metabolismo Energético , Masculino , Motilidade dos Espermatozoides
8.
Sci Rep ; 6: 26807, 2016 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-27226238

RESUMO

This study was designed to investigate the effect of U50,488H (a selective κ-opioid receptor agonist) on endothelial function impaired by hyperlipidemia and to determine the role of Akt-stimulated NO production in it. Hyperlipidemic model was established by feeding rats with a high-fat diet for 14 weeks. U50,488H and nor-BNI (a selective κ-opioid receptor antagonist) were administered intraperitoneally. In vitro, the involvement of the PI3K/Akt/eNOS pathway in the effect of U50,488H was studied using cultured endothelial cells subjected to artificial hyperlipidemia. Serum total cholesterol and low-density lipoprotein cholesterol concentrations dramatically increased after high-fat diet feeding. Administration of U50,488H significantly alleviated endothelial ultrastructural destruction and endothelium-dependent vasorelaxation impairment caused by hyperlipidemia. U50,488H also increased Akt/eNOS phosphorylation and serum/medium NO level both in vivo and in vitro. U50,488H increased eNOS activity and suppressed iNOS activity in vivo. The effects of U50,488H were abolished in vitro by siRNAs targeting κ-opioid receptor and Akt or PI3K/Akt/eNOS inhibitors. All effects of U50,488H were blocked by nor-BNI. These results demonstrate that κ-opioid receptor stimulation normalizes endothelial ultrastructure and function under hyperlipidemic condition. Its mechanism is related to the preservation of eNOS phosphorylation through activation of the PI3K/Akt signaling pathway and downregulation of iNOS expression/activity.


Assuntos
Células Endoteliais/efeitos dos fármacos , Hiperlipidemias/metabolismo , Óxido Nítrico/biossíntese , Proteínas Proto-Oncogênicas c-akt/fisiologia , Receptores Opioides kappa/fisiologia , (trans)-Isômero de 3,4-dicloro-N-metil-N-(2-(1-pirrolidinil)-ciclo-hexil)-benzenoacetamida/farmacologia , Animais , Aorta/efeitos dos fármacos , Aorta/metabolismo , Aorta/ultraestrutura , Glicemia/metabolismo , Dieta Hiperlipídica/efeitos adversos , Células Endoteliais/fisiologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Fígado/metabolismo , Fígado/patologia , Masculino , Naltrexona/análogos & derivados , Naltrexona/farmacologia , Óxido Nítrico Sintase/fisiologia , Fosfatidilinositol 3-Quinases/fisiologia , Ratos , Ratos Sprague-Dawley , Receptores Opioides kappa/agonistas , Receptores Opioides kappa/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos
9.
J Appl Physiol (1985) ; 114(2): 238-44, 2013 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-23139366

RESUMO

Impairment of pulmonary endothelium function in the pulmonary artery is a direct result of chronic hypoxia. This study is to investigate the vasculoprotective effects of U50,488H (a selective κ-opioid receptor agonist) and its underlying mechanism in hypoxia-induced pulmonary artery endothelial functional injury. Chronic hypoxia was simulated by exposing the rats to 10% oxygen for 2 wk. After hypoxia, right ventricular pressure (RVP) and right ventricular hypertrophy index (RVHI) were measured. The pulmonary vascular dysfunction, effect of nitric oxide synthase inhibitor (l-NAME) on the relaxation of U50,488H, and level of nitric oxide (NO) were determined. In vitro, the signaling pathway involved in the anti-apoptotic effect of U50,488H was investigated. Cultured endothelial cells were subjected to simulated hypoxia, and cell apoptosis was determined by TUNEL staining. U50,488H (1.25 mg/kg) significantly reduced RVP and RVHI in hypoxia. U50,488H markedly improved both pulmonary endothelial function (maximal vasorelaxation in response to ACh: 74.9 ± 1.8%, n = 6, P <0.01 vs. hypoxia for 2 wk group) and increased total NO production (1.65 fold). U50,488H relaxed the pulmonary artery rings of the hypoxic rats. This effect was partly abolished by l-NAME. In cells, U50,488H both increased NO production and reduced hypoxia-induced apoptosis. Moreover, pretreatment with nor-binaltorphimine (nor-BNI, a selective κ-opioid receptor antagonist), PI3K inhibitor, Akt inhibitor or l-NAME almost abolished anti-apoptotic effect exerted by U50,488H. U50,488H resulted in increases in Akt and eNOS phosphorylation. These results demonstrate that pretreatment with U50,488H attenuates hypoxia-induced pulmonary vascular endothelial dysfunction in an Akt-dependent and NO-mediated fashion.


Assuntos
(trans)-Isômero de 3,4-dicloro-N-metil-N-(2-(1-pirrolidinil)-ciclo-hexil)-benzenoacetamida/farmacologia , Endotélio Vascular/efeitos dos fármacos , Hipóxia/metabolismo , Óxido Nítrico/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores Opioides kappa/agonistas , Animais , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Células Cultivadas , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Técnicas In Vitro , Masculino , Modelos Animais , Naltrexona/análogos & derivados , Naltrexona/farmacologia , Óxido Nítrico Sintase Tipo III/metabolismo , Fosforilação , Artéria Pulmonar/citologia , Artéria Pulmonar/efeitos dos fármacos , Artéria Pulmonar/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores Opioides kappa/antagonistas & inibidores
10.
PLoS One ; 7(12): e51223, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23284668

RESUMO

This study was designed to investigate whether Resveratrol (Res) could be a prophylactic factor in the prevention of I/R injury and to shed light on its underlying mechanism. Primary culture of neonatal rat cardiomyocytes were randomly distributed into three groups: the normal group (cultured cardiomyocytes were in normal conditions), the I/R group (cultured cardiomyocytes were subjected to 2 h simulated ischemia followed by 4 h reperfusion), and the Res+I/R group (100 µmol/L Res was administered before cardiomyocytes were subjected to 2 h simulated ischemia followed by 4 h reperfusion). To test the extent of cardiomyocyte injury, several indices were detected including cell viability, LDH activity, Na(+)-K(+)-ATPase and Ca(2+)-ATPase activity. To test apoptotic cell death, caspase-3 activity and the expression of Bcl-2/Bax were detected. To explore the underlying mechanism, several inhibitors, intracellular calcium, SOD activity and MDA content were used to identify some key molecules involved. Res increased cell viability, Na(+)-K(+)-ATPase and Ca(2+)-ATPase activity, Bcl-2 expression, and SOD level. While LDH activity, capase-3 activity, Bax expression, intracellular calcium and MDA content were decreased by Res. And the effect of Res was blocked completely by either L-NAME (an eNOS inhibitor) or MB (a cGMP inhibitor), and partly by either DS (a PKC inhibitor) or Glybenclamide (a K(ATP) inhibitor). Our results suggest that Res attenuates I/R injury in cardiomyocytes by preventing cell apoptosis, decreasing LDH release and increasing ATPase activity. NO, cGMP, PKC and K(ATP) may play an important role in the protective role of Res. Moreover, Res enhances the capacity of anti-oxygen free radical and alleviates intracellular calcium overload in cardiomyocytes.


Assuntos
Cardiotônicos/farmacologia , Miócitos Cardíacos/efeitos dos fármacos , Traumatismo por Reperfusão/patologia , Traumatismo por Reperfusão/prevenção & controle , Estilbenos/farmacologia , Animais , Animais Recém-Nascidos , Apoptose/efeitos dos fármacos , Cálcio/metabolismo , ATPases Transportadoras de Cálcio/metabolismo , Caspase 3/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , L-Lactato Desidrogenase/metabolismo , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/metabolismo , Resveratrol , ATPase Trocadora de Sódio-Potássio/metabolismo , Proteína X Associada a bcl-2/metabolismo
11.
Arch Med Res ; 40(4): 227-34, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19608010

RESUMO

BACKGROUND AND AIMS: It remains unclear whether U50488H (a selective kappa-opioid receptor agonist) produces anti-apoptotic effect during ischemia and reperfusion (I/R). Therefore, the effect of U50488H on myocardial apoptosis was investigated in the present study. METHODS: Rats were subjected to 45min coronary artery occlusion and 180min of reperfusion. U50488H (1.5mg/kg IV) was given prior to occlusion. Nor-Binaltorphimine (nor-BNI) (2mg/kg IV), a selective kappa-opioid receptor antagonist, was given 10min prior to U50488H. Cardiac apoptosis was evaluated by terminal deoxynucleotidyl transferase mediated dUTP-biotin nick end labeling (TUNEL) assay and in situ identification of nuclear DNA fragmentation. RESULTS: The ultrastructure injury of myocardium, myocardial infarct size, and plasma CK and LDH were reduced significantly with administration of U50488H before I/R, whereas the effects of U50488H were abolished by nor-BNI. DNA fragments were visualized by agarose electrophoresis, and clear DNA ladder formation was observed in myocardial tissue from hearts subjected to I/R. Administration of U50488H before ischemia exerted a significant anti-apoptotic effect as evidenced by markedly weaker DNA ladder formation. TUNEL staining showed U50488H treatment before I/R significantly reduced the percentage of apoptotic cells, which was blocked by 5-HD, a mitochondrial k(ATP) channel blocker. In accordance, U50488H treatment significantly inhibited I/R-induced elevated activities of caspase-3 and caspase-9. U50488H also produced an increase in Bcl-2 and a decrease in Bax protein expression in the I/R heart, and the anti-apoptotic effects of U50488H were all blocked by nor-BNI. CONCLUSIONS: U50488H reduces myocardial necrosis and apoptosis after I/R and activation of kappa-opioid receptor may mediate a role in U50488H-induced myocardial protection.


Assuntos
(trans)-Isômero de 3,4-dicloro-N-metil-N-(2-(1-pirrolidinil)-ciclo-hexil)-benzenoacetamida/uso terapêutico , Apoptose/efeitos dos fármacos , Infarto do Miocárdio/prevenção & controle , Receptores Opioides kappa/agonistas , Traumatismo por Reperfusão/tratamento farmacológico , Animais , Anti-Hipertensivos/farmacologia , Caspase 3/efeitos dos fármacos , Caspase 3/metabolismo , Caspase 9/efeitos dos fármacos , Caspase 9/metabolismo , Fragmentação do DNA/efeitos dos fármacos , Masculino , Microscopia Eletrônica de Transmissão , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/patologia , Miocárdio/patologia , Naltrexona/análogos & derivados , Naltrexona/farmacologia , Antagonistas de Entorpecentes/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/complicações , Traumatismo por Reperfusão/patologia , Proteína X Associada a bcl-2/efeitos dos fármacos , Proteína X Associada a bcl-2/metabolismo
12.
J Appl Physiol (1985) ; 105(2): 569-74, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18511523

RESUMO

The modulation of beta-adrenoceptor signaling in the hearts of hindlimb unweighting (HU) simulated weightlessness rats has not been reported. In the present study, we adopted the rat tail suspension for 4 wk to simulate weightlessness; then the effects of simulated microgravity on beta-adrenoceptor signaling were studied. Mean arterial blood pressure (ABP), left ventricular pressure (LVP), systolic function (+dP/dtmax), and diastolic function (-dP/dtmax) were monitored in the course of the in vivo experiment. Single rat ventricular myocyte was obtained by the enzymatic dissociation method. Hemodynamics, myocyte contraction, and cAMP production in response to beta-adrenoceptor stimulation with isoproterenol or adenylyl cyclase stimulation with forskolin were measured, and Gs protein was also determined. Compared with the control group, no significant changes were found in heart weight, body weight and ABP, while LVP and +/-dP/dtmax were significantly reduced. The ABP decrease, LVP increase, and +/-dP/dtmax in response to isoproterenol administration were significantly attenuated in the HU group. The effects of isoproterenol on electrically induced single-cell contraction and cAMP production in myocytes of ventricles in the HU rats were significantly attenuated. The biologically active isoform, Gsalpha (45 kDa) in the heart, was unchanged. Both the increased electrically induced contraction and cAMP production in response to forskolin were also significantly attenuated in the simulated weightlessness rats. Above results indicated that impaired function of adenylyl cyclase causes beta-adrenoceptor desensitization, which may be partly responsible for the depression of cardiac function.


Assuntos
Coração/fisiologia , Receptores Adrenérgicos beta/fisiologia , Transdução de Sinais/fisiologia , Simulação de Ausência de Peso , Adenilil Ciclases/metabolismo , Agonistas Adrenérgicos beta/farmacologia , Anestesia , Animais , Peso Corporal/fisiologia , Colforsina/farmacologia , AMP Cíclico/metabolismo , Estimulação Elétrica , Elevação dos Membros Posteriores/fisiologia , Isoproterenol/farmacologia , Masculino , Contração Muscular/fisiologia , Contração Miocárdica/fisiologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/fisiologia , Tamanho do Órgão/fisiologia , Ratos , Ratos Sprague-Dawley
13.
Artigo em Chinês | MEDLINE | ID: mdl-16027783

RESUMO

OBJECTIVE: To explore the changes and relationship between serum soluble P-selectin, tumor necrosis factor-alpha (TNF-alpha) in coronary heart disease patients with acute coronary syndrome (ACS) and human cytomegalovirus (HCMV) infection. METHODS: The levels of circulating soluble P-selectin, TNF-alpha, HCMV-IgM and HCMV-IgG were determined by enzyme-linked immunosorbent assay (ELISA) in 79 cases for ACS group, 30 cases for stable angina (SA) group and 30 healthy control cases. RESULTS: (1) The serum positive rate of HCMV-IgM and HCMV-IgG in the ACS, SA and healthy control groups were 30.4% (24/79), 10.0% (3/30) and 6.7% (2/30); 86.1% (68/79), 80.0% (24/30) and 53.3% (16/30), respectively. Positive rate of HCMV-IgM in the ACS was higher than those in SA and healthy control groups (P < 0.01), positive rate of HCMV-IgG in the ACS and SA groups were higher than that of the healthy control group (P < 0.01). (2) Compared with the SA group and healthy control group, the levels of the serum soluble P-selectin and TNF-alpha were significantly higher in patients with ACS [(6437.3 +/- 666.9) pg/ml vs. (1520.0 +/- 112.7) pg/ml and (1481.0 +/- 109.1) pg/ml, (56.2 +/- 18.4) pg/ml vs. (27.3 +/- 13.7) pg/ml and (28.1 +/- 11.3) pg/ml], respectively, P < 0.01). The AMI group, compared with the UA group in the ACS group, had significantly higher levels of the serum soluble P-selectin and TNF-alpha (P < 0.01). Compared with the SA group, the levels of the serum soluble P-selectin and TNF-alpha were not significantly different in healthy control group. (3) The levels of the serum soluble P-selectin and TNF-alpha in HCMV-IgM positive patients were significantly higher than the HCMV-IgM negative patients in the ACS group (P < 0.01). CONCLUSION: The chronic infection with HCMV might injure endothelial cells that subsequently contribute to the formation and progression of atherosclerosis, the acute infection with HCMV may induce increased serum levels of soluble P-selectin and TNF-alpha that might participate in acute coronary events.


Assuntos
Síndrome Coronariana Aguda/sangue , Infecções por Citomegalovirus/sangue , Citomegalovirus/fisiologia , Selectina-P/sangue , Fator de Necrose Tumoral alfa/sangue , Síndrome Coronariana Aguda/virologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Citomegalovirus/imunologia , Infecções por Citomegalovirus/virologia , Ensaio de Imunoadsorção Enzimática , Feminino , Interações Hospedeiro-Patógeno , Humanos , Imunoglobulina M/sangue , Masculino , Pessoa de Meia-Idade
14.
Sheng Li Xue Bao ; 54(1): 7-11, 2002 Feb 25.
Artigo em Chinês | MEDLINE | ID: mdl-11930233

RESUMO

The present work was to investigate the effects of vasonatrin peptide (VNP) on cardiomyocyte protein synthesis induced by moderate hypoxia. In cultured neonatal rat cardiomyocytes, MTT methods, total protein measurement and (3)H-leucine incorporation were used to calculate the cell number and measure the protein synthesis of cardiomyocytes. Furthermore, radioimmunoassay was undertaken to observe the effects of VNP on the intracellular levels of cAMP, cGMP and the concentration of endothelin (ET) in the culture medium. The results showed that both the cell number and protein synthesis decreased with severe hypoxia for 24 h. In contrast, under moderate hypoxia, cardiomyocyte hypertrophy developed; the protein synthesis as evidenced by total protein content and 3H-eucine incorporation increased significantly. VNP reduced cardiomyocyte protein synthesis induced by moderate hypoxia in a dose-dependent manner. Furthermore, VNP increased the intracellular level of cGMP and decreased the concentration of ET in the culture medium under moderate hypoxia, but had no effect on the level of cAMP. These results suggest that VNP inhibits moderate hypoxia-induced protein synthesis in cultured neonatal rat cardiac myocytes. This effect is mediated, at least in part, by an increase in intracellular cGMP, a reduction in synthesis, and/or a release in ET of cardiomyocytes.


Assuntos
Fator Natriurético Atrial/farmacologia , Miócitos Cardíacos/metabolismo , Biossíntese de Proteínas , Animais , Animais Recém-Nascidos , Hipóxia Celular , Células Cultivadas , AMP Cíclico/metabolismo , GMP Cíclico/metabolismo , Relação Dose-Resposta a Droga , Endotelinas/biossíntese , Ratos , Ratos Sprague-Dawley
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