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1.
Biochem Biophys Res Commun ; 696: 149542, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38244315

RESUMO

PDZ domain-containing RING finger family protein 3 (PDZRN3) is expressed in various tissues, including the skeletal muscle. Although PDZRN3 plays a crucial role in the terminal differentiation of myoblasts and synaptic growth/maturation in myogenesis, the role of this molecule in postnatal muscles is completely unknown despite its lifelong expression in myofibers. In this study, we aimed to elucidate the function of PDZRN3 in mature myofibers using myofiber-specific conditional knockout mice. After tamoxifen injection, PDZRN3 deficiency was confirmed in both fast and slow myofibers of Myf6-CreERT2; Pdzrn3flox/flox (Pdzrn3mcKO) mice. Transcriptome analysis of the skeletal muscles of Pdzrn3mcKO mice identified differentially expressed genes, including muscle atrophy-related genes such as Smox, Amd1/2, and Mt1/2, suggesting that PDZRN3 is involved in the homeostatic maintenance of postnatal muscles. PDZRN3 deficiency caused muscle atrophy, predominantly in fast-twitch (type II) myofibers, and reduced muscle strength. While myofiber-specific PDZRN3 deficiency did not influence endplate morphology or expression of neuromuscular synaptic formation-related genes in postnatal muscles, indicating that the relationship between PDZRN3 and neuromuscular junctions might be limited during muscle development. Considering that the expression of Pdzrn3 in skeletal muscles was significantly lower in aged mice than in mature adult mice, we speculated that the PDZRN3-mediated muscle maintenance system might be associated with the pathophysiology of age-related muscle decline, such as sarcopenia.


Assuntos
Músculo Esquelético , Sarcopenia , Camundongos , Animais , Músculo Esquelético/metabolismo , Atrofia Muscular/metabolismo , Junção Neuromuscular/patologia , Sarcopenia/patologia , Mioblastos/metabolismo , Camundongos Knockout , Ubiquitina-Proteína Ligases/metabolismo
2.
Biochem Biophys Res Commun ; 709: 149709, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38554603

RESUMO

Ischemia-reperfusion (I/R) leads to tissue damage in transplanted kidneys, resulting in acute kidney injury (AKI) and chronic graft dysfunction, which critically compromises transplant outcomes, such as graft loss. Linaclotide, a guanylate cyclase C agonist clinically approved as a laxative, has recently been identified to exhibit renoprotective effects in a chronic kidney disease (CKD) model. This study evaluates the therapeutic effects of linaclotide on AKI triggered by I/R in a rat model with an initial comparison with other laxatives. Here, we show that linaclotide administration resulted in substantial reduction in serum creatinine levels, reflective of enhanced renal function. Histological examination revealed diminished tubular damage, and Sirius Red staining confirmed less collagen deposition, collectively indicating preserved structural integrity and mitigation of fibrosis. Further analysis demonstrated lowered expression of TGF-ß and associated fibrotic markers, α-SMA, MMP2, and TIMP1, implicating the downregulation of the fibrogenic TGF-ß pathway by linaclotide. Furthermore, one day after I/R insult, linaclotide profoundly diminished macrophage infiltration and suppressed critical pro-inflammatory cytokines such as TNF, IL-1ß, and IL-6, signifying its potential to disrupt initial inflammatory mechanisms integral to AKI pathology. These findings suggest that linaclotide, with its established safety profile, could extend its benefits beyond gastrointestinal issues and potentially serve as a therapeutic intervention for organ transplantation. Additionally, it could provide immediate and practical insights into selecting laxatives for managing patients with AKI or CKD, regardless of the cause, and for those receiving dialysis or transplant therapy.


Assuntos
Injúria Renal Aguda , Peptídeos , Insuficiência Renal Crônica , Traumatismo por Reperfusão , Humanos , Ratos , Animais , Laxantes/metabolismo , Laxantes/farmacologia , Laxantes/uso terapêutico , Traumatismo por Reperfusão/complicações , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/metabolismo , Rim/patologia , Injúria Renal Aguda/tratamento farmacológico , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/prevenção & controle , Insuficiência Renal Crônica/patologia , Isquemia/patologia , Reperfusão , Fator de Crescimento Transformador beta/metabolismo , Fibrose
3.
Cancer Sci ; 113(11): 3960-3971, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36028467

RESUMO

To identify liquid biomarkers that predict clinical outcomes of epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI), we enrolled patients with EGFR gene mutation-positive non-small-cell lung cancer who were intended to receive gefitinib treatment. Using plasma samples obtained prior to gefitinib treatment from 12 enrolled patients, we performed comprehensive proteomic analysis of plasma exosomes to explore proteins correlating with tumor reduction rate (TRR), progression-free survival (PFS), or overall survival (OS). Of the detected 1769 proteins, 119, 130, or 119 proteins demonstrated a strong correlation (|r| > 0.5) with TRR, PFS, or OS, respectively. Interestingly, 34 (29%), 41 (32%), or 27 (23%) of them, respectively, were functionally involved in the regulation of the immune response. CD8α chain was consistently listed as a molecule positively correlated with PFS and OS, suggesting that the long-lasting effects of gefitinib may be due to the antitumor effects of CD8+ T cells, as well as the induction of immunogenic apoptosis of tumor cells by blocking the EGFR signaling pathway. Notably, Doking Protein 3 (DOK3), a molecule involved in B-cell receptor signaling, and some immunoglobulin and complement molecules exhibited a clear correlation with PFS longevity of gefitinib treatment. Indeed, the strong expression of DOK3 in B cells was confirmed within tertiary lymphoid structures of lung cancer tissues derived from patients with long PFS. These findings suggest that the patients with active B-cell and T-cell immunity as a host immunological feature are more likely to benefit from gefitinib therapy. Circulating exosomal DOK3 has the potential as a predictive marker of response to gefitinib indicating this immunological feature.


Assuntos
Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas , Gefitinibe , Neoplasias Pulmonares , Humanos , Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Linfócitos T CD8-Positivos/patologia , Receptores ErbB/genética , Gefitinibe/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Mutação , Prognóstico , Inibidores de Proteínas Quinases/uso terapêutico , Proteômica , Quinazolinas/uso terapêutico , Exossomos
4.
Biochem Biophys Res Commun ; 624: 141-145, 2022 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-35940127

RESUMO

Dantrolene inhibits Ca2+ leakage from destabilized ryanodine receptors and therefore may serve as a therapeutic agent against endoplasmic reticulum stress-associated diseases. However, its effectiveness in treating autoimmune diseases remains unclear. Here, we investigated the effect of dantrolene on collagen-induced arthritis (CIA) in mice. Oral administration of dantrolene resulted in significantly lower arthritic scores in both male and female CIA mice than in the control mice. Micro-computed tomographic and histological analyses showed that dantrolene suppressed bone and chondral destruction. The serum levels of anti-type II collagen (CII) IgG were positively correlated with the arthritic scores (r = 0.704, p < 0.01). In addition, the serum levels of anti-CII IgG were significantly lower in the dantrolene group than in the control group (p < 0.05). These results demonstrate that oral administration of dantrolene to CIA mice inhibits the production of serum anti-CII IgG and consequently prevents arthritis. Therefore, dantrolene may be a potential anti-rheumatic drug.


Assuntos
Artrite Experimental , Animais , Artrite Experimental/patologia , Colágeno Tipo II , Dantroleno/farmacologia , Dantroleno/uso terapêutico , Feminino , Imunoglobulina G , Masculino , Camundongos , Camundongos Endogâmicos DBA , Canal de Liberação de Cálcio do Receptor de Rianodina
5.
Kyobu Geka ; 74(11): 937-940, 2021 Oct.
Artigo em Japonês | MEDLINE | ID: mdl-34601477

RESUMO

A 73-year-old man underwent echocardiography in order to assess any cardiac risk prior to surgery for renal cancer, and a large mobile mass was incidentally identified in his left ventricular outflow tract. Since a metastatic cardiac tumor was suspected, surgical resection of the mass was performed under cardiopulmonary bypass and hypothermic circulatory arrest. The mass had peduncles in the anterior leaflet of the mitral valve, the interventricular septum, and the papillary muscles. They were carefully removed by approaching through the aortic valve, and macroscopically suspected to be accessory mitral valve tissue. We observed the mitral valve via a transseptal approach to assess the function of the mitral valve and, as a result, a double-orifice mitral valve was identified. We should bear in mind that asymptomatic accessory mitral valve tissue can sometimes be detected in elderly patients, and is commonly associated with other congenital cardiac anomalies.


Assuntos
Cardiopatias Congênitas , Insuficiência da Valva Mitral , Obstrução do Fluxo Ventricular Externo , Idoso , Ecocardiografia , Humanos , Masculino , Valva Mitral/diagnóstico por imagem , Valva Mitral/cirurgia , Insuficiência da Valva Mitral/diagnóstico por imagem , Insuficiência da Valva Mitral/cirurgia
6.
J Cell Physiol ; 234(3): 2963-2972, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30066954

RESUMO

PDZRN3 (also known as LNX3) is a member of the PDZ domain-containing RING finger protein family. We previously showed that PDZRN3 is essential for differentiation of myoblasts into myotubes and that depletion of PDZRN3 inhibits such differentiation downstream of the upregulation of myogenin, a basic helix-loop-helix (bHLH) transcription factor required for completion of the differentiation process. However, the mechanism by which PDZRN3 controls this process has remained unclear. Myogenin is rendered active during the late stage of myogenic differentiation by the downregulation of Id2, a negative regulator of bHLH transcription factors. We now show that depletion of PDZRN3 inhibits the differentiation of C2C12 cells by inducing the upregulation of Id2 and thereby delaying its downregulation. Knockdown of Id2 by RNA interference restores the differentiation of PDZRN3-depleted cells. Luciferase reporter assays revealed that a putative binding site for STAT5b in the Id2 gene promoter is required for the upregulation of Id2 expression by PDZRN3 depletion. In addition, the amount of phosphorylated Id2 was reduced and that of the nonphosphorylated protein concomitantly increased in PDZRN3-depleted cells, with the inhibitory effect of Id2 on bHLH transcription factors having previously been shown to be attenuated by phosphorylation of Id2 catalyzed by the complex of Cdk2 with cyclin A2 or E1. Indeed, the expression of cyclin A2, but not that of cyclin E1, was reduced in PDZRN3-depleted cells. Our results thus indicate that PDZRN3 plays a key role in the differentiation of myoblasts into myotubes by regulating Id2 at both transcriptional and posttranslational levels.


Assuntos
Diferenciação Celular/genética , Proteína 2 Inibidora de Diferenciação/genética , Transcrição Gênica , Ubiquitina-Proteína Ligases/genética , Animais , Sítios de Ligação , Linhagem Celular , Ciclina A2/genética , Proteínas de Ligação a DNA/genética , Humanos , Camundongos , Desenvolvimento Muscular/genética , Fibras Musculares Esqueléticas/metabolismo , Mioblastos/metabolismo , Fosforilação , Regiões Promotoras Genéticas , Processamento de Proteína Pós-Traducional/genética , Fator de Transcrição STAT5/genética
7.
Kyobu Geka ; 72(13): 1049-1052, 2019 Dec.
Artigo em Japonês | MEDLINE | ID: mdl-31879377

RESUMO

We retrospectively assessed our initial clinical experience of the herbal medicine Inchinkoto for refractory hyperbilirubinemia following open-heart surgery. Six patients developed hyperbilirubinemia in an acute phase after surgery and their maximum total bilirubin levels were 6.4~26.4 mg/dl( mean:13.1± 8.2 mg/dl). They were initially treated with ursodeoxycholic acid and/or Stronger Neo-Minophagen C containing monoammonium glycyrrhizinate, glycine, aminoacetic acid, and L-cysteine hydrochloride hydrate. These treatments, however, were ineffective, and Inchinkoto was introduced at 5~34 day (mean:13.3±11.3 days) after surgery. Hyperbilirubinemia improved in all patients after the introduction of Inchinkoto:1 day after in 1 case, 2 days after in 2 cases, 3 days after in 2 cases, and 4 days after in 1 case. These results indicate the potential of Inchinkoto to attenuate refractory hyperbilirubinemia following cardiac surgery with cardiopulmonary bypass.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Medicina Herbária , Humanos , Hiperbilirrubinemia , Estudos Prospectivos , Estudos Retrospectivos
8.
Bioconjug Chem ; 29(8): 2829-2837, 2018 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-30107743

RESUMO

Atrial natriuretic peptide (ANP) exerts beneficial pharmacological effects in the treatment of various cardiovascular disorders, such as acute congestive heart failure (ADHF). However, the clinical use of ANP is limited to the continuous intravenous infusion owing to its short half-life (2.4 ± 0.7 min). In the present study, we conjugated the glyco-modified ANP with a monoclonal antibody (mAb) or an Fc via chemo-enzymatic glyco-engineering using EndoS D233Q/Q303L. The most potent derivative SG-ANP-Fc conjugate extended the half-life to 14.9 d and the duration of blood pressure lowering effect to over 28 d. This new biologic modality provides an opportunity to develop outpatient therapy after ADHF.


Assuntos
Fator Natriurético Atrial/farmacologia , Fator Natriurético Atrial/farmacocinética , Animais , Anticorpos Monoclonais/química , Fator Natriurético Atrial/síntese química , Fator Natriurético Atrial/química , Células CHO , Cricetulus , GMP Cíclico/agonistas , GMP Cíclico/sangue , Glicosilação , Meia-Vida , Humanos , Imunoconjugados/sangue , Macaca fascicularis , Masculino , Ratos , Ratos Wistar
9.
Bioorg Med Chem Lett ; 26(6): 1542-1545, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26898815

RESUMO

Trastuzumab conjugates consisting of exatecan derivatives were prepared and their biological activities and physicochemical properties were evaluated. The ADCs showed strong efficacy and a low aggregation rate. The exatecan derivatives were covalently connected via a peptidyl spacer (Gly-Gly-Phe-Gly), which is assumed to be stable in circulation, and were cleaved by lysosomal enzymes following ADC internalization into tumor tissue. These anti-HER2 ADCs exhibited a high potency, specifically against HER2-positive cancer cell lines in vitro. The ADCs, bearing exatecan derivatives which have more than two methylene chains, exhibited superior cytotoxicity. It was speculated that steric hindrance of the cleavable amide moiety could be involved in the drug release. The adequate alkyl lengths of exatecan derivatives (13, 14, 15) were from two to four in terms of aggregation rate. The ADC having a hydrophilic moiety showed good efficacy in a HER2-positive and Trastuzumab-resistant breast carcinoma cell model in mice.


Assuntos
Anticorpos Monoclonais Humanizados/química , Antineoplásicos/química , Antineoplásicos/farmacologia , Camptotecina/análogos & derivados , Neoplasias Mamárias Experimentais/tratamento farmacológico , Trastuzumab/farmacologia , Animais , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/farmacologia , Antineoplásicos/administração & dosagem , Camptotecina/administração & dosagem , Camptotecina/química , Camptotecina/metabolismo , Camptotecina/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Injeções Intraventriculares , Neoplasias Mamárias Experimentais/patologia , Camundongos , Conformação Molecular , Relação Estrutura-Atividade , Trastuzumab/administração & dosagem , Trastuzumab/química
10.
J Heart Valve Dis ; 25(6): 685-690, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-28290167

RESUMO

BACKGROUND: An evaluation was made of the early clinical outcomes and efficacies of simple interrupted suturing (SIS) for redo mitral valve replacement (MVR). METHODS: Among 336 mitral valve surgery patients at the authors' institution between April 2000 and May 2014, a total of 21 redo MVR using SIS (12 women, nine men; mean age 67±11 years; range 32-80 years) participated in the study. Surgical indications for redo MVR were paravalvular leakage (PVL) in 10 patients, prosthetic valve endocarditis in five, mechanical valve thrombosis in three, and structural valve deterioration (SVD) of the bioprosthesis in three. The number of previous surgeries was one in 10 patients, two in seven, and three in four. With regards to surgical technique, sharp dissection was initially performed on one side of the previous prosthetic sewing cuff, and the overall sewing cuff was thereafter completely removed following leaflet detachment. SIS (mean number of sutures 32.5 ± 3.0; range: 28-40 sutures) was performed to implant the new prosthesis, without exposing the rough surface of the previous mitral valve annulus, thereby allowing for eventual implantation of the same-sized or larger-sized prosthesis. RESULTS: The surgical procedure was successfully performed in all patients without any serious complications. Bioprostheses were selected for 11 patients, and mechanical valves for 10. Sixteen patients (76.2%) received a new prosthesis that was the same size as or larger than the previous prosthesis. Operative mortality within 30 days was 4.8%, which was similar to that of primary MVR in the same period (n = 83; 2.4%; p = 0.57). Recurrent PVL was detected in only one patient, who underwent a fourth surgery for SVD of the bioprosthesis. CONCLUSIONS: SIS for redo MVR may allow for the implantation of larger prostheses, and this novel maneuver may achieve acceptable early clinical outcomes.


Assuntos
Implante de Prótese de Valva Cardíaca/métodos , Valva Mitral/cirurgia , Reoperação/métodos , Técnicas de Sutura , Adulto , Idoso , Idoso de 80 Anos ou mais , Bioprótese , Endocardite/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Insuficiência da Valva Mitral/cirurgia , Falha de Prótese , Estudos Retrospectivos , Trombose/cirurgia
11.
Mol Pharmacol ; 87(2): 277-85, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25473119

RESUMO

Re-epithelialization begins early during skin wound healing and is regulated by various growth factors and cytokines. Angiotensin II promotes the migration of keratinocytes and thereby contributes to wound healing. We investigated the mechanism by which angiotensin II stimulates human keratinocyte migration. Angiotensin II-induced keratinocyte migration was inhibited by an angiotensin II type 1 receptor (AT1R) antagonist (candesartan) or an angiotensin II type 2 receptor (AT2R) antagonist (PD123319) as well as by depletion of AT1R or AT2R. A biased agonist for AT1R, [Sar(1),Ile(4),Ile(8)]angiotensin II, induced cell migration, whereas depletion of ß-arrestin2 inhibited angiotensin II-induced migration. Angiotensin II-induced migration was blocked by neutralizing antibodies to transforming growth factor-ß (TGF-ß) as well as by the TGF-ß receptor inhibitor SB431542. The amount of TGF-ß1 was increased in the culture medium of angiotensin II-treated cells, and this effect was inhibited by candesartan or PD123319. Both angiotensin II- and TGF-ß-induced cell migration were inhibited by neutralizing antibodies to the epidermal growth factor (EGF) receptor but not by those to EGF receptor ligands. Angiotensin II-induced phosphorylation of the EGF receptor, and this effect was inhibited by candesartan, PD123319, SB431542, or depletion of ß-arrestin2, but not by neutralizing antibodies to heparin-binding EGF-like growth factor. Our results indicate that ß-arrestin-dependent signaling downstream of AT1R as well as AT2R signaling are necessary for angiotensin II-induced keratinocyte migration, and that such signaling promotes generation of the active form of TGF-ß, consequent activation of the TGF-ß receptor, and transactivation of the EGF receptor by the TGF-ß receptor.


Assuntos
Angiotensina II/farmacologia , Movimento Celular/fisiologia , Queratinócitos/fisiologia , Transdução de Sinais/fisiologia , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Humanos , Queratinócitos/efeitos dos fármacos , Masculino , Transdução de Sinais/efeitos dos fármacos
12.
Bioorg Med Chem ; 23(17): 5546-65, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-26234904

RESUMO

GPR40 agonists stimulate insulin secretion only under the presence of high glucose concentration. Based on this mechanism, GPR40 agonists are believed to be promising novel insulin secretagogues with low risk of hypoglycemia. The optimizations of 3-aryl-3-ethoxypropanoic acids were performed to improve in vitro activity. We discovered compound 29r (DS-1558), (3S)-3-ethoxy-3-(4-{[(1R)-4-(trifluoromethyl)-2,3-dihydro-1H-inden-1-yl]oxy}phenyl)propanoic acid, which was confirmed to have an enhancing effect on glucose-dependent insulin secretion after intravenous glucose injection in SD rats.


Assuntos
Indanos/metabolismo , Fenilpropionatos/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Animais , Humanos , Hipoglicemiantes , Estrutura Molecular , Ratos
13.
J Mol Cell Cardiol ; 76: 177-85, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25240642

RESUMO

The sarco(endo)plasmic reticulum Ca(2+)-ATPase 2a (SERCA2a)-phospholamban (PLN) system of sarcoplasmic reticulum plays a pivotal role in regulation of intracellular Ca(2+) cycling in ventricular cardiomyocytes. Given that Ca(2+) cycling is impaired in heart failure, proteins that contribute to this process are potential targets for the treatment of this condition. We have now isolated PLN-specific aptamers with a phosphorothioate-modified backbone from a library of RNA molecules containing a randomized 40-nucleotide sequence by application of the systematic evolution of ligands by exponential enrichment (SELEX) protocol with a fusion protein containing the cytoplasmic region of human PLN. One of these aptamers was shortened to a 30-nucleotide oligomer (RNA-Apt30) without loss of function. RNA-Apt30 showed a high affinity for the cytoplasmic region of PLN (Kd=11 nM), but it did not bind to the phosphorylated form of PLN or to a phosphomimetic mutant. It also increased SERCA2a activity in isolated cardiac SR vesicles with an EC50 of 18 nM by relieving PLN-mediated inhibition. Conjugation of RNA-Apt30 to a cell-penetrating peptide allowed its delivery into adult rat cardiomyocytes, in which it enhanced both Ca(2+) transients and contractile function. These effects of the aptamer were also apparent in the presence of the ß-adrenergic receptor antagonist propranolol. This cell-penetrating PLN aptamer may thus provide a basis for the development of new therapeutic agents for heart failure without the need for gene transfer or a change in endogenous protein expression.


Assuntos
Aptâmeros de Nucleotídeos/farmacologia , Sinalização do Cálcio/efeitos dos fármacos , Proteínas de Ligação ao Cálcio/metabolismo , Peptídeos Penetradores de Células/farmacologia , Miócitos Cardíacos/fisiologia , Animais , Aptâmeros de Nucleotídeos/química , Sequência de Bases , Proteínas de Ligação ao Cálcio/química , Peptídeos Penetradores de Células/química , Células Cultivadas , Cães , Masculino , Dados de Sequência Molecular , Contração Miocárdica , Miócitos Cardíacos/efeitos dos fármacos , Ligação Proteica , Coelhos , Ratos Wistar , Retículo Sarcoplasmático/metabolismo , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo
14.
PLoS Pathog ; 8(7): e1002803, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22829766

RESUMO

Vibrio parahaemolyticus is one of the human pathogenic vibrios. During the infection of mammalian cells, this pathogen exhibits cytotoxicity that is dependent on its type III secretion system (T3SS1). VepA, an effector protein secreted via the T3SS1, plays a major role in the T3SS1-dependent cytotoxicity of V. parahaemolyticus. However, the mechanism by which VepA is involved in T3SS1-dependent cytotoxicity is unknown. Here, we found that protein transfection of VepA into HeLa cells resulted in cell death, indicating that VepA alone is cytotoxic. The ectopic expression of VepA in yeast Saccharomyces cerevisiae interferes with yeast growth, indicating that VepA is also toxic in yeast. A yeast genome-wide screen identified the yeast gene VMA3 as essential for the growth inhibition of yeast by VepA. Although VMA3 encodes subunit c of the vacuolar H(+)-ATPase (V-ATPase), the toxicity of VepA was independent of the function of V-ATPases. In HeLa cells, knockdown of V-ATPase subunit c decreased VepA-mediated cytotoxicity. We also demonstrated that VepA interacted with V-ATPase subunit c, whereas a carboxyl-terminally truncated mutant of VepA (VepAΔC), which does not show toxicity, did not. During infection, lysosomal contents leaked into the cytosol, revealing that lysosomal membrane permeabilization occurred prior to cell lysis. In a cell-free system, VepA was sufficient to induce the release of cathepsin D from isolated lysosomes. Therefore, our data suggest that the bacterial effector VepA targets subunit c of V-ATPase and induces the rupture of host cell lysosomes and subsequent cell death.


Assuntos
Sistemas de Secreção Bacterianos , Lisossomos/metabolismo , ATPases Vacuolares Próton-Translocadoras/metabolismo , Vibrio parahaemolyticus/metabolismo , Fatores de Virulência/metabolismo , Apoptose , Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Catepsina D/metabolismo , Linhagem Celular Tumoral , Células HeLa , Humanos , Macrófagos/metabolismo , Interferência de RNA , RNA Interferente Pequeno , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , ATPases Vacuolares Próton-Translocadoras/genética , Vibrio parahaemolyticus/patogenicidade , Fatores de Virulência/biossíntese
15.
Bioorg Med Chem Lett ; 24(13): 2949-53, 2014 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-24835985

RESUMO

The G protein-coupled receptor 40 (GPR40) mediates enhancement of glucose-stimulated insulin secretion in pancreatic ß cells. The GPR40 agonist has been attracting attention as a novel insulin secretagogue with glucose dependency for the treatment of type 2 diabetes. The optimization study of compound 1 led to a potent and bioavailable GPR40 agonist 24, which showed insulin secretion and glucose lowering effects in rat OGTT. Compound 24 is a potential lead compound for a novel insulin secretagogue with a low risk of hypoglycemia.


Assuntos
Descoberta de Drogas , Propionatos/farmacologia , Receptores Acoplados a Proteínas G/agonistas , Administração Oral , Animais , Glicemia/efeitos dos fármacos , Relação Dose-Resposta a Droga , Teste de Tolerância a Glucose , Humanos , Estrutura Molecular , Propionatos/administração & dosagem , Propionatos/química , Ratos , Ratos Endogâmicos F344 , Ratos Zucker , Relação Estrutura-Atividade
17.
Am J Physiol Cell Physiol ; 304(11): C1091-7, 2013 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-23576576

RESUMO

PDZRN3, a member of the PDZRN (or LNX) family of proteins, is essential for the differentiation of mesenchymal stem cells into myotubes, but it plays an inhibitory role in the differentiation of these cells into osteoblasts. Given that mesenchymal stem cells also differentiate into adipocytes, we examined the possible role of PDZRN3 in adipogenesis in mouse 3T3-L1 preadipocytes. The expression of PDZRN3 decreased at both the mRNA and protein levels during adipogenic differentiation. RNAi-mediated depletion of PDZRN3 enhanced the differentiation of 3T3-L1 cells into adipocytes as assessed on the basis of lipid accumulation. The upregulation of aP2 and CCAAT/enhancer-binding protein (C/EBP)-ß during adipocyte differentiation was also enhanced in the PDZRN3-depleted cells, as was the induction of peroxisome proliferator-activated receptor-γ (PPARγ), an upstream regulator of aP2 and C/EBPα, at both the mRNA and protein levels. Among transcription factors that control the expression of PPARγ, we found that STAT5b, but not STAT5a, was upregulated in PDZRN3-depleted cells at both mRNA and protein levels. Tyrosine phosphorylation of STAT5b, but not that of STAT5a, was also enhanced at an early stage of differentiation by PDZRN3 depletion. In addition, the expression of C/EBPß during the induction of differentiation was enhanced at the mRNA and protein levels in PDZRN3-depleted cells. Our results thus suggest that PDZRN3 negatively regulates adipogenesis in 3T3-L1 cells through downregulation of STAT5b and C/EBPß and consequent suppression of PPARγ expression.


Assuntos
Adipócitos/citologia , Adipogenia/fisiologia , Proteínas de Transporte/metabolismo , Diferenciação Celular/fisiologia , Regulação da Expressão Gênica/fisiologia , Transdução de Sinais/fisiologia , Ubiquitina-Proteína Ligases/metabolismo , Adipócitos/metabolismo , Animais , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Linhagem Celular , Immunoblotting , Imunoprecipitação , Camundongos , PPAR gama/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Transcrição STAT5/metabolismo
18.
J Infect Chemother ; 19(5): 909-15, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23645226

RESUMO

Pneumonia is associated with an extremely high mortality rate in patients of late elderly age. Piperacillin/tazobactam and carbapenems are drugs of first choice for hospitalized patients with potentially resistant bacteria. We compared the efficacy and safety of piperacillin/tazobactam and biapenem. Among elderly patients with nursing- and healthcare-associated pneumonia, we extracted 53 patients treated with piperacillin/tazobactam and 53 patients treated with biapenem who were matched for sex, age, and severity of pneumonia. The average age was more than 80 years; most of the patients were middle- to oldest old in age. Although clinical efficacy was equally good, patients in the piperacillin/tazobactam group achieved significantly faster improvements on chest X-ray and body temperature on day 7. However, in the piperacillin/tazobactam group, nephrotoxicity frequently led to a need for a reduction in the dose or complete discontinuation of treatment. The average age of patients who developed significant nephrotoxicity was high, at 83.2 years. The biapenem group exhibited significantly better continuation of treatment than the piperacillin/tazobactam group. Toxicity profiles were different between the two groups. Hepatic toxicity was significantly higher in the biapenem group, whereas nephrotoxicity was significantly more common in the piperacillin/tazobactam group. Rate of decrease in bacteria was equally good between the two groups. Providing careful follow-up and conducting more detailed examinations, including studies to determine optimal dose and timing of administration, are necessary for the treatment of late elderly patients with numerous underlying diseases and potential organ dysfunctions.


Assuntos
Infecção Hospitalar/tratamento farmacológico , Ácido Penicilânico/análogos & derivados , Pneumonia Bacteriana/tratamento farmacológico , Tienamicinas/efeitos adversos , Tienamicinas/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/efeitos adversos , Antibacterianos/uso terapêutico , Infecção Hospitalar/microbiologia , Feminino , Hospitalização , Humanos , Masculino , Ácido Penicilânico/efeitos adversos , Ácido Penicilânico/uso terapêutico , Piperacilina/efeitos adversos , Piperacilina/uso terapêutico , Combinação Piperacilina e Tazobactam , Pneumonia Bacteriana/microbiologia , Estudos Retrospectivos , Escarro/microbiologia
19.
Proc Natl Acad Sci U S A ; 107(19): 8794-9, 2010 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-20421480

RESUMO

Cholera and enterotoxigenic Escherichia coli (ETEC) are among the most common causes of acute infantile gastroenteritis globally. We previously developed a rice-based vaccine that expressed cholera toxin B subunit (MucoRice-CTB) and had the advantages of being cold chain-free and providing protection against cholera toxin (CT)-induced diarrhea. To advance the development of MucoRice-CTB for human clinical application, we investigated whether the CTB-specific secretory IgA (SIgA) induced by MucoRice-CTB gives longstanding protection against diarrhea induced by Vibrio cholerae and heat-labile enterotoxin (LT)-producing ETEC (LT-ETEC) in mice. Oral immunization with MucoRice-CTB stored at room temperature for more than 3 y provided effective SIgA-mediated protection against CT- or LT-induced diarrhea, but the protection was impaired in polymeric Ig receptor-deficient mice lacking SIgA. The vaccine gave longstanding protection against CT- or LT-induced diarrhea (for > or = 6 months after primary immunization), and a single booster immunization extended the duration of protective immunity by at least 4 months. Furthermore, MucoRice-CTB vaccination prevented diarrhea in the event of V. cholerae and LT-ETEC challenges. Thus, MucoRice-CTB is an effective long-term cold chain-free oral vaccine that induces CTB-specific SIgA-mediated longstanding protection against V. cholerae- or LT-ETEC-induced diarrhea.


Assuntos
Vacinas contra Cólera/imunologia , Escherichia coli Enterotoxigênica/imunologia , Enterotoxinas/imunologia , Vacinas contra Escherichia coli/imunologia , Imunoglobulina A Secretora/imunologia , Oryza/imunologia , Vibrio cholerae/imunologia , Administração Oral , Animais , Toxina da Cólera/imunologia , Vacinas contra Cólera/administração & dosagem , Proteção Cruzada/imunologia , Diarreia/imunologia , Diarreia/microbiologia , Diarreia/prevenção & controle , Vacinas contra Escherichia coli/administração & dosagem , Feminino , Temperatura Alta , Imunidade/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Receptores Imunológicos/imunologia , Vacinação
20.
Eur J Cancer ; 195: 113373, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37890349

RESUMO

BACKGROUND: Although concurrent chemoradiotherapy (CCRT) followed by durvalumab is the standard treatment for patients with stage III non-small cell lung cancer (NSCLC), only half of the patients are allowed to receive CCRT in real-world settings. We evaluated the efficacy and safety of durvalumab after radiation monotherapy for NSCLC patients who are ineligible for chemoradiotherapy. METHODS: A single-arm, prospective, open-label, multicenter phase II trial was conducted in Japan. The patients received radiation (54-66 Gy) followed by durvalumab (10 mg/kg every 2 weeks for up to 12 months). The primary endpoint was the 1-year progression-free survival (PFS) rate. The secondary endpoints were the objective response rate (ORR), PFS, overall survival (OS), and safety. RESULTS: Between September 2019 and April 2021, 33 patients were enroled from eight institutions. The median patient age was 79 years, and the majority of patients were male (78.8%). The 1-year PFS rate was 39.1% (90% confidence interval [CI]: 24.7-54.6%). Three patients (9.1%) had a performance status of 2. The ORR was 42.4% (95% CI: 27.2-59.2%). The median PFS and OS were 8.9 (95% CI: 7.4-19.4) and 20.8 (95% CI: 15.8-not estimable) months, respectively. The most common adverse event was radiation pneumonitis (51.5%). The median treatment duration was 6.4 (range: 0.50-12.0) months for durvalumab. At the endpoint, 30.3% (10/33) of the patients had completed 1 year of durvalumab therapy. CONCLUSIONS: Durvalumab is an effective treatment with tolerable toxicity following radiation monotherapy in stage III NSCLC patients who are ineligible for chemoradiotherapy. TRIAL REGISTRATION: JMA-IIA00434 (jRCT).


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Idoso , Feminino , Humanos , Masculino , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Quimiorradioterapia , Neoplasias Pulmonares/tratamento farmacológico , Estadiamento de Neoplasias , Estudos Prospectivos
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