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1.
J Cell Physiol ; 238(1): 242-256, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36538623

RESUMO

Myocardial hypertrophy is associated with a significant increase in intracellular Ca2+ , which can be induced by long-chain fatty acid. Palmitic acid methyl ester (PAME), a fatty acid ester released from adipose tissue, superior cervical ganglion, and retina, has been found to have anti-inflammation, antifibrosis, and peripheral vasodilation effects. However, the effects of PAME on cardiomyocytes are still unclear. The aim of this study was to determine whether PAME could disrupt the intracellular Ca2+ balance, leading to cardiomyocyte hypertrophy. Neonatal rat cardiomyocytes were treated with various concentrations (10-100 µM) of PAME for 1-4 days. Cytosolic Ca2+ and mitochondrial Ca2+ concentrations were examined using Fura-2 AM and Rhod-2, respectively. After treatment with PAME for 4 days, mitochondrial Ca2+ , an indicator of the state of mitochondrial permeability transition pore (MPTP), and cell death were monitored by flow cytometric analysis. ATP levels were detected using the ATP assay kit. Cardiomyocyte hypertrophy was analyzed by measuring the cardiac hypertrophy biomarker and cell area using quantitative real time-polymerase chain reaction, Western Blot analysis and immunofluorescence analysis. Our results show that PAME concentration- and time-dependently increased cytosolic and mitochondria Ca2+ through the mitochondrial calcium uniporter. Moreover, treatment with PAME for 4 days caused MPTP opening, thereby reducing ATP production and enhancing reactive oxygen species (ROS) generation, and finally led to cardiomyocyte hypertrophy. These effects caused by PAME treatment were attenuated by the G-protein coupled receptor 40 (GPR40) inhibitor. In conclusion, PAME impaired mitochondrial function, which in turn led to cardiomyocyte hypertrophy through increasing the mitochondrial Ca2+ levels mediated by activating the GPR40 signaling pathway.


Assuntos
Cálcio , Mitocôndrias , Palmitatos , Receptores Acoplados a Proteínas G , Animais , Ratos , Trifosfato de Adenosina/metabolismo , Cálcio/metabolismo , Cardiomegalia/induzido quimicamente , Cardiomegalia/metabolismo , Mitocôndrias/metabolismo , Miócitos Cardíacos/metabolismo , Palmitatos/farmacologia , Receptores Acoplados a Proteínas G/metabolismo , Células Cultivadas
2.
Antimicrob Agents Chemother ; 64(10)2020 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-32690650

RESUMO

A multicenter collection of bacteremic isolates of Escherichia coli (n = 423), Klebsiella pneumoniae (n = 372), Pseudomonas aeruginosa (n = 300), and Acinetobacter baumannii complex (n = 199) was analyzed for susceptibility. Xpert Carba-R assay and sequencing for mcr genes were performed for carbapenem- or colistin-resistant isolates. Nineteen (67.8%) carbapenem-resistant K. pneumoniae (n = 28) and one (20%) carbapenem-resistant E. coli (n = 5) isolate harbored blaKPC (n = 17), blaOXA-48 (n = 2), and blaVIM (n = 1) genes.


Assuntos
Antibacterianos , beta-Lactamases , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Farmacorresistência Bacteriana/genética , Escherichia coli/genética , Bactérias Gram-Negativas/genética , Testes de Sensibilidade Microbiana , Taiwan , beta-Lactamases/genética
3.
Eur J Nutr ; 59(6): 2333-2344, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31502059

RESUMO

PURPOSE: We previously demonstrated that progesterone (P4) interacted with folic acid (FA) and abolished the FA-reduced endothelial cell proliferation and migration. These findings led us to investigate whether FA can interfere with the P4-promoted breast cancer cell proliferation and migration. METHODS: We conducted MTT and wound healing assay to evaluate cell proliferation and migration, respectively. Western blot analysis and immunoprecipitation were performed to examine the protein expression and protein-protein interaction, respectively. RESULTS: We demonstrated that P4 promoted proliferation and migration of breast cancer cell lines (T47D, MCF-7, BT474, and BT483). However, co-treatment with P4 and FA together abolished these promotion effects. Treatment with P4 alone increased the formation of PR-cSrc complex and the phosphorylation of cSrc at tyrosine 416 (Tyr416). However, co-treatment with P4 and FA together increased the formations of cSrc-p140Cap, cSrc-Csk, and cSrc-p-Csk complex, and the phosphorylation of cSrc at tyrosine 527 (Tyr527). Co-treatment with P4 and FA together also abolished the activation of cSrc-mediated signaling pathways involved in the P4-promoted breast cancer cell proliferation and migration. CONCLUSIONS: Co-treatment with FA and P4 together abolished the P4-promoted breast cancer cell proliferation and migration through decreasing the formation of PR-cSrc complex and increasing the formations of cSrc-p140Cap and cSrc-Csk complex, subsequently activating Csk, which in turn suppressed the phosphorylation of cSrc at Tyr416 and increased the phosphorylation of cSrc at Tyr527, hence inactivating the cSrc-mediated signaling pathways. The findings from this study might provide a new strategy for preventing the P4-promoted breast cancer progress.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ácido Fólico/farmacologia , Progesterona/antagonistas & inibidores , Linhagem Celular Tumoral , Progressão da Doença , Humanos , Células MCF-7 , Progesterona/farmacologia
4.
Chin J Physiol ; 63(6): 256-262, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33380610

RESUMO

Atherosclerosis and associated pathologies, such as coronary artery disease, peripheral vascular disease, and stroke, are still the leading cause of death in Western society. The impact of female sex hormones on cardiovascular diseases has been studied intensively with conflicting findings. The controversy is mainly due to the differences in groups sampling, animal models used, hormonal treatment regimens, and the data analyzed. In the present article, the results of in vitro and in vivo studies and clinical trials are under review.


Assuntos
Aterosclerose , Animais , Aterosclerose/etiologia , Doença da Artéria Coronariana , Feminino , Hormônios Esteroides Gonadais
5.
Artigo em Inglês | MEDLINE | ID: mdl-31138577

RESUMO

Cefoperazone, a third-generation cephamycin with broad-spectrum antibacterial activity and the ability to permeate bacterial cell membranes, is active against commonly encountered multidrug-resistant pathogens for hospital-acquired pneumonia (HAP) and health care-associated pneumonia (HCAP). To clarify the clinical effects of cefoperazone-sulbactam in the treatment of HAP and HCAP, we conducted an open-label, randomized, noninferiority trial that recruited patients aged ≥18 years suffering HAP/HCAP. Participants were randomly assigned to the cefoperazone-sulbactam (2 g of each per 12 h) or cefepime (2 g per 12 h) arm. Clinical and microbiological responses were evaluated at early posttherapy and test-of-cure visits. Recruited patients were allocated to subpopulations for intent-to-treat (n = 154), per-protocol (n = 147), and safety (n = 166) analyses. Intent-to-treat analysis demonstrated that (i) at the early posttherapy visit, 87.3% of patients receiving cefoperazone-sulbactam and 84.3% of patients receiving cefepime achieved clinical improvement or cure (risk difference of 3.0%; 95% confidence interval [CI], -9.0% to 15.0%), and (ii) at the test-of-cure visit, 73.1% of patients receiving cefoperazone-sulbactam and 56.8% of patients receiving cefepime were assessed as cured (risk difference of 16.3%; 95% CI, 0.0% to 33.0%). These results indicated the noninferiority of cefoperazone-sulbactam to cefepime, which was confirmed by per-protocol analysis. The chest radiographic consolidation/infiltration resolution rate, microbiological eradiation rate, and percentage of adverse events were comparable in both groups. Serious adverse events were rare, and none was judged to be related to the study drugs. Cefoperazone-sulbactam at 2 g every 12 h was noninferior to cefepime at 2 g every 2 h for patients with HCAP.


Assuntos
Antibacterianos/uso terapêutico , Cefepima/uso terapêutico , Cefoperazona/uso terapêutico , Pneumonia Associada a Assistência à Saúde/tratamento farmacológico , Sulbactam/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/efeitos adversos , Cefepima/efeitos adversos , Cefoperazona/efeitos adversos , Quimioterapia Combinada , Feminino , Infecções por Haemophilus/tratamento farmacológico , Pneumonia Associada a Assistência à Saúde/microbiologia , Humanos , Masculino , Pessoa de Meia-Idade , Pneumonia Bacteriana/tratamento farmacológico , Infecções por Pseudomonas/tratamento farmacológico , Sulbactam/efeitos adversos , Resultado do Tratamento
6.
J Mol Cell Cardiol ; 118: 122-132, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29577873

RESUMO

Intermittent hypoxia (IH) has been shown to exert cardioprotective effects against ischemia/reperfusion (I/R) injury through the preservation of ion homeostasis. I/R dramatically elevated cytosolic Zn2+ and caused cardiomyocyte death. However, the role of IH exposure in the relationship between Zn2+ regulation and cardioprotection is still unclear. The aim of the present study was to study whether IH exposure could help in intracellular Zn2+ regulation, hence contributing to cardioprotection against I/R injury. Adult rat cardiomyocytes were exposed to IH (5% O2, 5% CO2 and balanced N2) for 30 min followed by 30 min of normoxia (21% O2, 5% CO2 and balanced N2). Changes in intracellular Zn2+ concentration were determined using a Zn2+-specific fluorescent dye, FluoZin-3 or RhodZin-3. Fluorescence was monitored under an inverted fluorescent or confocal microscope. The results demonstrated that I/R or 2,2'-dithiodipyridine (DTDP), a reactive disulphide compound, induced Zn2+ release from metallothioneins (MTs), subsequently causing cytosolic Zn2+ overload, which in turn increased intracellular Zn2+ entry into the mitochondria via a Ca2+ uniporter, hence inducing mitochondrial membrane potential loss, and eventually led to cell death. However, the cytosolic Zn2+ overload and cell death caused by I/R or DTDP was significantly reduced by treatment of cardiomyocytes with IH. The findings from this study suggest that IH might exert its cardioprotective effect through reducing the I/R-induced cytosolic Zn2+ overload and cell death in cardiomyocytes.


Assuntos
Hipóxia/patologia , Espaço Intracelular/metabolismo , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Espécies Reativas de Oxigênio/metabolismo , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia , Zinco/metabolismo , 2,2'-Dipiridil/análogos & derivados , 2,2'-Dipiridil/farmacologia , Animais , Cardiotônicos/metabolismo , Morte Celular/efeitos dos fármacos , Dissulfetos/farmacologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Metalotioneína/metabolismo , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Modelos Biológicos , Miócitos Cardíacos/efeitos dos fármacos , Ratos Sprague-Dawley
8.
J Cell Biochem ; 116(7): 1411-8, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25754581

RESUMO

We previously showed that progesterone (P4) could inhibit the proliferation of human umbilical venous endothelial cells (HUVECs) through the p53-dependent pathway. In the present study, we further demonstrated that P4 at physiologic levels (5-500 nM) concentration-dependently inhibited migration of HUVECs. This effect was blocked by pre-treatment with the P4 receptor (PR) agonist-antagonist, RU486, suggesting that the P4-induced migration inhibition in HUVECs was through the PR-mediated signaling pathway. Western blot analyses demonstrated that the levels of RhoA and Rac-1 protein were reduced in the P4-treated HUVECs. P4 also inhibited the membrane translocation of RhoA and Rac-1 protein. Moreover, the P4-induced migration inhibition in HUVECs was prevented by over-expression of the constitutively active RhoA construct (RhoA V14). However, pre-treatment with the ROCK (a kinase associated with RhoA for transducing RhoA signaling) inhibitor, Y27632, abolished the over-expression of RhoA-induced prevention effect on the P4-induced migration inhibition in HUVECs. These data suggest that the inhibition of Rho GTPases might account for the P4-induced migration inhibition of HUVECs. Pre-treatment with the cSrc inhibitor, PP2, prevented the P4-induced migration inhibition in HUVEC. The levels of phosphorylated focal adhesion kinase (FAK) and paxillin protein were also decreased by P4 treatment. Taken together, these results suggest that suppression of the Rho-mediated pathway might be involved in the signal transduction leading to the inhibition of cell migration caused by P4 in HUVECs.


Assuntos
Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Progesterona/farmacologia , Proteínas rac1 de Ligação ao GTP/metabolismo , Proteína rhoA de Ligação ao GTP/metabolismo , Quinases da Família src/metabolismo , Movimento Celular/efeitos dos fármacos , Regulação para Baixo , Antagonistas de Hormônios/farmacologia , Humanos , Mifepristona/farmacologia , Pirimidinas/farmacologia , Transdução de Sinais/efeitos dos fármacos , Quinases da Família src/antagonistas & inibidores
9.
Am J Physiol Endocrinol Metab ; 309(10): E829-39, 2015 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-26394662

RESUMO

Nε-(carboxymethyl) lysine-conjugated bovine serum albumin (CML-BSA) is a major component of advanced glycation end products (AGEs). We hypothesised that AGEs reduce insulin secretion from pancreatic ß-cells by damaging mitochondrial functions and inducing mitophagy. Mitochondrial morphology and the occurrence of autophagy were examined in pancreatic islets of diabetic db/db mice and in the cultured CML-BSA-treated insulinoma cell line RIN-m5F. In addition, the effects of α-lipoic acid (ALA) on mitochondria in AGE-damaged tissues were evaluated. The diabetic db/db mouse exhibited an increase in the number of autophagosomes in damaged mitochondria and receptor for AGEs (RAGE). Treatment of db/db mice with ALA for 12 wk increased the number of mitochondria with well-organized cristae and fewer autophagosomes. Treatment of RIN-m5F cells with CML-BSA increased the level of RAGE protein and autophagosome formation, caused mitochondrial dysfunction, and decreased insulin secretion. CML-BSA also reduced mitochondrial membrane potential and ATP production, increased ROS and lipid peroxide production, and caused mitochondrial DNA deletions. Elevated fission protein dynamin-related protein 1 (Drp1) level and mitochondrial fragmentation demonstrated the unbalance of mitochondrial fusion and fission in CML-BSA-treated cells. Additionally, increased levels of Parkin and PTEN-induced putative kinase 1 protein suggest that fragmented mitochondria were associated with increased mitophagic activity, and ALA attenuated the CML-BSA-induced mitophage formation. Our study demonstrated that CML-BSA induced mitochondrial dysfunction and mitophagy in pancreatic ß-cells. The findings from this study suggest that increased concentration of AGEs may damage ß-cells and reduce insulin secretion.


Assuntos
Diabetes Mellitus/metabolismo , Produtos Finais de Glicação Avançada/metabolismo , Células Secretoras de Insulina/metabolismo , Insulina/metabolismo , Lisina/análogos & derivados , Dinâmica Mitocondrial , Mitofagia , Animais , Antioxidantes/metabolismo , Antioxidantes/uso terapêutico , Biomarcadores/metabolismo , Linhagem Celular Tumoral , Diabetes Mellitus/dietoterapia , Diabetes Mellitus/patologia , Suplementos Nutricionais , Regulação para Baixo/efeitos dos fármacos , Produtos Finais de Glicação Avançada/antagonistas & inibidores , Produtos Finais de Glicação Avançada/farmacologia , Secreção de Insulina , Células Secretoras de Insulina/efeitos dos fármacos , Células Secretoras de Insulina/ultraestrutura , Lisina/antagonistas & inibidores , Lisina/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Camundongos Mutantes , Dinâmica Mitocondrial/efeitos dos fármacos , Mitofagia/efeitos dos fármacos , Oxidantes/antagonistas & inibidores , Oxidantes/farmacologia , Fagossomos/efeitos dos fármacos , Fagossomos/metabolismo , Fagossomos/ultraestrutura , Ratos , Receptor para Produtos Finais de Glicação Avançada/agonistas , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Soroalbumina Bovina/antagonistas & inibidores , Soroalbumina Bovina/farmacologia , Ácido Tióctico/metabolismo , Ácido Tióctico/uso terapêutico
11.
Int J Clin Pharmacol Ther ; 52(12): 1030-6, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25345432

RESUMO

OBJECTIVE: Clinical information on tigecycline use in serious nosocomial infections is limited, and the efficacy is uncertain. The aim of this retrospective study was to assess the utilization pattern and the effectiveness of tigecycline in a tertiary medical center in Taiwan. METHODS: A retrospective study of the clinical and microbiological outcome of all patients treated with tigecycline for at least 72 hours over a 2-year period was conducted in a 730-bed teaching hospital. RESULTS: Data from 133 patients with 149 cases of nosocomial infection were analyzed in this assessment. The mean APACHE II score at the initiation of tigecycline therapy was 22.5 ± 8.8, and the mean duration of treatment was 11.4 ± 5.6 days. Pneumonia was the most frequently diagnosed clinical indication for tigecycline use (113 cases, 76%). An overall positive clinical outcome was observed in 75 cases (50%). Multidrug-resistant Acinetobacter baumannii (MDRAB) is the most common organism for tigecycline therapy (n = 59), with a positive clinical outcome of 38% in tigecycline monotherapy, 66% in dualtherapy, and 17% in triple-therapy (p = 0.031). The most commonly used combining agents with tigecycline to treat MDRAB infections were intravenous colistin, inhaled colistin, and cepoferazone/sulbactam, with positive clinical outcome rates of 53%, 100%, and 80%, respectively. Admission to intensive care unit was identified as a predictive factor for negative clinical outcome. CONCLUSION: Our pneumonia-dominated study population demonstrated a lower clinical improvement rate of tigecycline compared to previous published data. Tigecycline monotherapy is not recommended for MDRAB infection, but colistin or cephoperazone/ sulbactam combined with tigecycline seemed to yield a good clinical outcome for MDRAB infection.


Assuntos
Infecções por Acinetobacter/tratamento farmacológico , Acinetobacter baumannii , Antibacterianos/uso terapêutico , Infecção Hospitalar/tratamento farmacológico , Minociclina/análogos & derivados , Idoso , Idoso de 80 Anos ou mais , Farmacorresistência Bacteriana , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Minociclina/uso terapêutico , Estudos Retrospectivos , Tigeciclina
12.
J Med Syst ; 37(2): 9923, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23321977

RESUMO

In this study, we propose an approach to build a detection model for surveillance of healthcare-associated urinary tract infection (HA-UTI) based on the variables extracted from the electronic medical records (EMRs) in a 730-bed, tertiary-care teaching hospital in Taiwan. Firstly we mapped the CDC's HA-UTI case definitions to a set of variables, and identified the variables whose values could be derived from the EMRs of the hospital automatically. Then with these variables we performed discriminant analysis (DA) on a training set of the EMRs to construct a discriminant function (DF) for the classification of a patient with or without HA-UTI. Finally, we evaluated the sensitivity, specificity, and overall accuracy of the function using a testing set of EMRs. In this study, six surveillance variables (fever, urine culture, blood culture, routine urinalysis, antibiotic use, and invasive devices) were identified whose values could be derived from the EMRs of the hospital. The sensitivity, specificity and overall accuracy of the built DF were 100 %, 94.61 %, and 94.65 %, respectively. Since most hospitals may adopt their EMRs piece-by-piece to meet their functional requirements, the variables that are available in the EMRs may differ. Our approach can build a detection model with these variables to achieve a high sensitivity, specificity and accuracy for automatically detecting suspected HA-UTI cases. Therefore, our approach on one hand can reduce the efforts in building the model; on the other hand, can facilitate adoption of EMRs for HAI surveillance and control.


Assuntos
Infecção Hospitalar/epidemiologia , Registros Eletrônicos de Saúde , Vigilância da População/métodos , Infecções Urinárias/diagnóstico , Coleta de Dados , Humanos , Sensibilidade e Especificidade , Taiwan/epidemiologia , Infecções Urinárias/epidemiologia
13.
J Nutr Biochem ; 112: 109205, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36455835

RESUMO

We previously demonstrated that activation of progesterone receptor (PR) is essential for folic acid (FA)-inhibited proliferation in colorectal cancer cell lines. In the present study, we further investigated whether the requirement of PR activation for the FA-regulated cell proliferation and migration is a general phenomenon for all cancer cell lines or specific for colorectal cancer cell lines only. Initially, we examined the expression of PR in various cancer cell lines using Western blot analyses and RT-PCR technique, and then investigated the effects of FA on these cancer cell lines. Our data showed that the effects of FA on proliferation and migration only occurred in the PR positive (+) cancer cell lines, but not the PR negative (-) cancer cell lines, and these effects were abolished by pre-treatment with the PR specific inhibitor, Org 31710. On the other hand, FA significantly reduced the proliferation and migration in the PR (-) cancer cell lines transfected with PR pcDNA. However, FA did not significantly affect the proliferation and migration in the PR-transefected Hep-3B cell line, which does not express endogenous PR and FA receptor (FR). Since we previously showed that FA-regulated proliferation in colorectal and breast cancer cell lines through the cSrc-mediated pathway, we conducted immunoprecipitation assay to demonstrate that PR formed a complex with FR and cSrc, but FR did not directly associate with cSrc. Taken together, these findings suggest that the requirement of PR activation for the FA-regulated cell proliferation and migration is a general phenomenon for all cancer cell lines.


Assuntos
Neoplasias Colorretais , Receptores de Progesterona , Humanos , Receptores de Progesterona/genética , Receptores de Progesterona/metabolismo , Ácido Fólico/farmacologia , Proliferação de Células , Neoplasias Colorretais/metabolismo , Linhagem Celular Tumoral , Progesterona
14.
Eur J Pharmacol ; 957: 176031, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37660967

RESUMO

Myocardial ischemia-reperfusion (I/R) injury triggers several cell death types, including apoptosis, autophagy, and ferroptosis. Licochalcone A (LCA), a natural flavonoid compound isolated from the root of Glycyrrhiza glabra, has been demonstrated to exert potential pharmacological benefits, such as antioxidant, antitumor, and anti-inflammatory activities. The present study aimed to investigate the involvement of ferroptosis in the pathogenesis of I/R and determine whether LCA can inhibit ferroptosis to prevent the myocardial I/R injury in rats. The effects of LCA on myocardial I/R injury were detected by examining the left ventricular-developed pressure and triphenyltetrazolium chloride staining. We conducted Western blotting analyses, ELISA assay, and quantitative real-time PCR to determine the levels of ferroptosis-related molecules. To demonstrate the cardioprotective effect of LCA in vitro, H9c2 and primary neonatal rat cardiomyocytes were co-treated with ferroptosis inducers (erastin, RSL3, or Fe-SP) and LCA for 16 and 24 h. Our ex vivo study showed that LCA increased the cardiac contractility, and reduced the infarct volume and ferroptosis-related biomarkers in rat hearts after I/R. Moreover, LCA reduced the levels of ferroptosis inducers-induced reactive oxygen species generation, lipid peroxidation, and ferroptosis-related biomarkers in cultured H9c2 cells and cardiomyocytes. LCA also reduced the Fe-SP-increased nuclear factor erythroid 2-related factor 2 and heme oxygenase-1 protein levels in cultured cardiomyocytes. In the present study, we showed that the LCA-induced cardioprotective effects in attenuating the myocardial I/R injury were correlated with ferroptosis regulation, and provided a possible new therapeutic strategy for prevention or therapy of the myocardial I/R injury.


Assuntos
Chalconas , Ferroptose , Animais , Ratos , Chalconas/farmacologia , Chalconas/uso terapêutico , Fenômenos Fisiológicos Cardiovasculares , Isquemia
15.
Int J Cardiol ; 375: 74-86, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36513286

RESUMO

BACKGROUND: Ischemia/reperfusion (I/R) is associated with severe cellular damage and death. Ferroptosis, a new form of regulated cell death caused by the accumulation of iron-mediated lipid peroxidation, has been found in several diseases including I/R injury, which was reported to be suppressed by flavonoids. Baicalein (BAI) and luteolin (Lut) are flavonoids and were shown to reduce the myocardial I/R injury. BAI was found to suppress ferroptosis in cancer cells via reducing reactive oxygen species (ROS) generation. However, the anti-ferroptosis effect of Lut on ferroptosis has not been reported. This study aimed to investigate whether ferroptosis reduction contributes to the BAI- and Lut-protected cardiomyocytes. METHODS: This research used erastin, RSL3, and Fe-SP to induce ferroptosis. Cell viability was examined using MTT assay. Annexin V-FITC, CM-H2DCFDA, and Phen Green SK diacetate (PGSK) fluorescent intensity were detected to analyze apoptotsis, ROS levels, and Fe2+ concentrations, respectively. qPCR and Western blot analysis were conducted to detect the levels of mRNA and protein, respectively. RESULTS: Our data show that BAI and Lut protected cardiomyocytes against ferroptosis caused by ferroptosis inducers and I/R. Moreover, both BAI and Lut decreased ROS and malondialdehyde (MDA) generation and the protein levels of ferroptosis markers, and restored Glutathione peroxidase 4 (GPX4) protein levels in cardiomyocytes reduced by ferroptosis inducers. BAI and Lut reduced the I/R-induced myocardium infarction and decreased the levels of Acsl4 and Ptgs2 mRNA. CONCLUSIONS: BAI and Lut could protect the cardiomyocytes against the I/R-induced ferroptosis via suppressing accumulation of ROS and MDA.


Assuntos
Traumatismo por Reperfusão Miocárdica , Miócitos Cardíacos , Ratos , Animais , Miócitos Cardíacos/metabolismo , Luteolina/farmacologia , Luteolina/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Traumatismo por Reperfusão Miocárdica/metabolismo , RNA Mensageiro/metabolismo , Reperfusão , Isquemia/metabolismo
16.
Clin Interv Aging ; 18: 869-880, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37284594

RESUMO

The impact of vaccinating the older population against vaccine-preventable diseases in terms of health, social and economic benefits has been increasingly recognised. However, there is a gap in the utilisation of vaccines worldwide. The population is ageing at an unprecedented pace in the Asia-Pacific (APAC) region, with the number of persons older than 65 years set to double by 2050 to around 1.3 billion. More than 18% of the population in Japan, Hong Kong, and China is over the age of 65 years. This highlights the importance of prioritising resources to address societal obligations toward the needs of the ageing generation. This review provides an overview of the challenges to adult vaccination in APAC, drivers to increase vaccination coverage, vaccination insights gained through the COVID-19 pandemic, and potential measures to increase the uptake of adult vaccines in the region.


Assuntos
COVID-19 , Vacinas , Humanos , Idoso , Pandemias , COVID-19/prevenção & controle , Vacinação , Hong Kong/epidemiologia
17.
Angiogenesis ; 15(4): 671-83, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22843228

RESUMO

Folate is important for normal cell division. Folate deficiency has been implicated in various diseases, including atherosclerosis, neural tube defects, and cancer. However, the effect of folate on angiogenesis was unclear. The aim of this study was to investigate the anti-angiogenic action of folic acid (FA). FA (0-10 µmol/L) concentration-dependently decreased DNA synthesis and proliferation in cultured human umbilical venous endothelial cells (HUVEC). Western blot analyses demonstrated that the levels of p21, p27 and p53 protein in HUVEC were increased by FA. The FA-inhibited [3H]thymidine incorporation was completely blocked when the expressions of p21 and p27 were knocked-down together. Knock-down of p53 prevented the FA-induced increases in p21 and p27 protein level. The levels of phosphorylated Src (p-Src) and p-Src-FA receptor (FR) complex in HUVEC were increased by FA. Knock-down of FR reduced the FA-induced increases of p-Src and p53. The FA-induced increases of p21, p27 and p53 protein levels were abolished when cSrc was knocked-down. FA also increased NF-κB nuclear translocation and binding onto the p53 promoter. The FA-induced up-regulation of the p53 promoter activity was prevented by knocked-down of ERK. Matrigel angiogenesis assay in mice demonstrate the anti-angiogenic effect of FA in vivo. In conclusion, our data indicate that FA bound to FR in HUVEC, subsequently activated the cSrc/ERK 2/NF-κB/p53 signaling pathway, which in turn up-regulated the expression of p21 and p27, and finally resulted in cell cycle arrest at the G0/G1 phase. In the present study, we uncover a completely novel role of FA for anti-angiogenesis.


Assuntos
Proliferação de Células/efeitos dos fármacos , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Ácido Fólico/farmacologia , NF-kappa B/metabolismo , Proteínas Proto-Oncogênicas pp60(c-src)/metabolismo , Receptores de Droga/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Células Cultivadas , Humanos
18.
Antimicrob Agents Chemother ; 56(10): 5016-22, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22802253

RESUMO

From June to September 2011, a total of 305 ertapenem-nonsusceptible Enterobacteriaceae isolates (MICs of ertapenem ≥ 1 µg/ml) were collected from 11 hospitals in different parts of Taiwan. The MICs of 12 antimicrobial agents against these isolates were determined using the broth microdilution method, and genes for carbapenemases were detected using PCR. Genotypes of isolates possessing carbapenemase genes were identified by pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing. The ertapenem-nonsusceptible Enterobacteriaceae isolates included Klebsiella pneumoniae (n = 219), Escherichia coli (n = 64), Enterobacter cloacae (n = 15), and other species (n = 7). Seven (2.3%) of the ertapenem-nonsusceptible Enterobacteriaceae isolates exhibited colistin MICs of >4 µg/ml, and 24 (7.9%) were not susceptible to tigecycline (MICs > 2 µg/ml). A total of 29 (9.5%) isolates carried genes encoding carbapenemases, namely, K. pneumoniae carbapenemase-2 (KPC-2) in 16 (7.3%) isolates of K. pneumoniae (KPC-2-KP) and IMP-8 in 5 (2.3%) isolates of K. pneumoniae, 5 (33.3%) isolates of E. cloacae, 1 isolate of E. coli, 1 isolate of Klebsiella oxytoca, and one isolate of Citrobacter freundii. The 16 KPC-2-KP isolates were isolated from patients at four different hospitals in northern Taiwan. All 16 of the KPC-2-KP isolates were susceptible to amikacin and colistin and had a similar pulsotype (pulsotype 1) and the same sequence type (sequence type 11). Infections due to KPC-2-KP mainly occurred in severely ill patients in the intensive care unit (n = 14, 88%). Four patients with infections due to KPC-2-KP died within 14 days of hospitalization. The findings are the first to demonstrate intrahospital and interhospital dissemination of KPC-2-KP in northern Taiwan.


Assuntos
Proteínas de Bactérias/metabolismo , Enterobacteriaceae/enzimologia , beta-Lactamases/metabolismo , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Citrobacter freundii/efeitos dos fármacos , Citrobacter freundii/enzimologia , Citrobacter freundii/genética , Citrobacter freundii/patogenicidade , Eletroforese em Gel de Campo Pulsado , Enterobacter cloacae/efeitos dos fármacos , Enterobacter cloacae/enzimologia , Enterobacter cloacae/genética , Enterobacter cloacae/patogenicidade , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/genética , Enterobacteriaceae/patogenicidade , Infecções por Enterobacteriaceae/tratamento farmacológico , Infecções por Enterobacteriaceae/microbiologia , Genótipo , Humanos , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/enzimologia , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/patogenicidade , Testes de Sensibilidade Microbiana , Minociclina/análogos & derivados , Minociclina/farmacologia , Minociclina/uso terapêutico , Reação em Cadeia da Polimerase , Tigeciclina
19.
Breast Cancer Res Treat ; 134(3): 989-1004, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22434522

RESUMO

The extracellular matrix (ECM) plays a critical role in the development and invasion of primary breast tumors. Lysyl oxidase (LOX), which is an ECM remodeling enzyme, appears to play roles in promoting cancer cell motility and invasion. To ascertain whether LOX overexpression in breast tumor tissues from Asian patients is associated with decreases in metastasis-free and overall survival in breast cancer patients, the mRNA levels of LOX were examined in paired tumor/normal tissue samples using real-time RT-PCR analysis (n = 246 pair-matched samples). To test whether specifically targeting LOX by inhibiting its activity (using beta-aminopropionitrile (ß-APN), a LOX inhibitor), mRNA expression (using siRNA), or protein expression (using 25 µM magnolol) attenuates the invasion of MDA-MB-231 breast cancer cells, a cancer cell migration assay was performed. Interestingly, only 78.5% (n = 193) of the breast cancer tumors displayed detectable LOX expression. Nearly 60% (n = 120) of the cases fell into Group 1 (tumor > normal, T > N); in this group, the mean LOX expression in the tumor cells was 20.2-fold greater than in normal cells. However, in Group 2 (normal > tumor, N > T), the LOX expression level in most of the normal tissues examined (80%, 59/73) was less than fivefold greater than in the tumor tissues. The increased level of active LOX in the invasive breast cancer cell line MDA-MB-231 was accompanied by the increased phosphorylation of focal adhesion kinase at Tyr-576 and of paxillin at Tyr-118. We also found that the addition of ß-APN (300 µM) and magnolol (25 µM), synergistically inhibited the migration and invasion of MDA-MB-231 cells. In this article, we describe, for the first time, higher expression of a LOX protein in breast tumors compared with normal tissues from Asian patients. Moreover, the results indicate that the inhibition of LOX using magnolol may represent a more desirable strategy for breast cancer therapy than the use of ß-APN.


Assuntos
Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Inibidores Enzimáticos/farmacologia , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Paxilina/metabolismo , Proteína-Lisina 6-Oxidase/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Adulto , Idoso , Neoplasias da Mama/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Regulação para Baixo/efeitos dos fármacos , Feminino , Expressão Gênica , Humanos , Peróxido de Hidrogênio/metabolismo , Pessoa de Meia-Idade , Metástase Neoplásica , Estadiamento de Neoplasias , Prognóstico , Proteína-Lisina 6-Oxidase/genética , Proteína-Lisina 6-Oxidase/metabolismo , RNA Mensageiro , Quinases da Família src/metabolismo
20.
Mol Carcinog ; 51(5): 389-99, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21563217

RESUMO

Terbinafine (TB), an oral antifungal agent used in the treatment of superficial mycosis, has been reported to exert an anti-tumor effect in various cancer cells. However, the effect of TB on oral cancer has not been evaluated. Herein we demonstrate that TB (0-60 µM) concentration-dependently decreased cell number in cultured human oral squamous cell carcinoma (OSCC), KB cells. The anti-proliferation effect of TB was also observed in two other OSCC cell lines, SAS and SCC 15. TB (60 µM) was not cytotoxic and its inhibition on KB cell growth was reversible. [(3) H]thymidine incorporation and flow cytometric analyses revealed that TB-inhibited DNA synthesis and induced the G0/G1 cell-cycle arrest. The TB-induced cell-cycle arrest occurred when the cyclin-dependent kinase 2 activity was inhibited just as the protein levels of p21(cip1) and p27(kip1) were increased. The TB-induced G0/G1 cell-cycle arrest was completely blocked when the expressions of p21(cip1) and p27(kip1) were knocked-down together. Taken together, these results suggest that the p21(cip1) - and p27(kip1) -associated signaling pathways might be involved in the TB-induced anti-proliferation in KB cells. In vivo, TB (50 mg/kg, i.p.) significantly inhibited the KB tumor size. In these TB-treated tumors, increases in the levels of p21(cip1) and p27(kip1) protein and decreases in the number of proliferating cell nuclear antigen-positive cells and the microvessel density were observed. These findings demonstrate for the first time that TB might have potential to serve as a therapeutic tool in the treatment of oral cancer.


Assuntos
Antineoplásicos/administração & dosagem , Carcinoma de Células Escamosas/metabolismo , Proliferação de Células/efeitos dos fármacos , Neoplasias Bucais/metabolismo , Naftalenos/administração & dosagem , Apoptose , Carcinoma de Células Escamosas/tratamento farmacológico , Linhagem Celular Tumoral , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Relação Dose-Resposta a Droga , Humanos , Neoplasias Bucais/tratamento farmacológico , Naftalenos/efeitos adversos , Neovascularização Patológica , Inibidores da Síntese de Ácido Nucleico/administração & dosagem , Inibidores da Síntese de Ácido Nucleico/efeitos adversos , Transdução de Sinais , Terbinafina
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