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1.
J Biol Chem ; 300(6): 107327, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38679330

RESUMO

Normal receptor tyrosine kinases (RTKs) need to reach the plasma membrane (PM) for ligand-induced activation, whereas its cancer-causing mutants can be activated before reaching the PM in organelles, such as the Golgi/trans-Golgi network (TGN). Inhibitors of protein export from the endoplasmic reticulum (ER), such as brefeldin A (BFA) and 2-methylcoprophilinamide (M-COPA), can suppress the activation of mutant RTKs in cancer cells, suggesting that RTK mutants cannot initiate signaling in the ER. BFA and M-COPA block the function of ADP-ribosylation factors (ARFs) that play a crucial role in ER-Golgi protein trafficking. However, among ARF family proteins, the specific ARFs inhibited by BFA or M-COPA, that is, the ARFs involved in RTKs transport from the ER, remain unclear. In this study, we showed that M-COPA blocked the export of not only KIT but also PDGFRA/EGFR/MET RTKs from the ER. ER-retained RTKs could not fully transduce anti-apoptotic signals, thereby leading to cancer cell apoptosis. Moreover, a single knockdown of ARF1, ARF3, ARF4, ARF5, or ARF6 could not block ER export of RTKs, indicating that BFA/M-COPA treatment cannot be mimicked by the knockdown of only one ARF member. Interestingly, simultaneous transfection of ARF1, ARF4, and ARF5 siRNAs mirrored the effect of BFA/M-COPA treatment. Consistent with these results, in vitro pulldown assays showed that BFA/M-COPA blocked the function of ARF1, ARF4, and ARF5. Taken together, these results suggest that BFA/M-COPA targets at least ARF1, ARF4, and ARF5; in other words, RTKs require the simultaneous activation of ARF1, ARF4, and ARF5 for their ER export.

2.
Clin J Gastroenterol ; 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38652377

RESUMO

Various autoimmune diseases have been reported to develop as a result of a coronavirus disease 19 (COVID-19) infection. There have been some reports of COVID-19-triggered autoimmune hepatitis and autoimmune hemolytic anemia infection, but none have reported simultaneous onset of these diseases. A 15-year-old girl was admitted to our hospital with severe liver injury and anemia. Three weeks before admission, her father was diagnosed with COVID-19, after which she became aware of a sore throat. Two weeks later, she visited her doctor for malaise. She was referred to our hospital due to severe anemia, elevated hepatobiliary enzymes, and jaundice. A COVID-19 polymerase chain reaction test was positive at the time of referral. She was diagnosed with autoimmune hemolytic anemia based on decreased hemoglobin and haptoglobin, positive direct Coombs test, and increased urinary urobilinogen. Blood tests were positive for antinuclear antibodies, and a liver biopsy revealed interface hepatitis and plasma cell infiltration, consistent with autoimmune hepatitis. Based on these findings, a diagnosis of autoimmune hepatitis and autoimmune hemolytic anemia triggered by COVID-19 infection was made. Steroid therapy was initiated, which resulted in rapid improvement of blood markers and symptoms.

3.
BMC Nutr ; 10(1): 32, 2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38395891

RESUMO

BACKGROUND: The onset of muscle loss in critically ill patients, known as intensive care unit-acquired weakness (ICU-AW), worsens their outcomes. Preventing muscle loss, which begins in the early phase of critical illness, is crucial in patient care. Adequate nutrition management may contribute to maintaining muscles; however, its evidence in patients with sepsis is insufficient. This study aimed to analyze the association between energy achievement rate in the first 7-days of critical care and muscle area changes evaluated by computed tomography (CT). METHODS: This was a retrospective observational study. Patients with sepsis admitted to the intensive care (ICU) of a tertiary care hospital in Japan were included. They were divided into three groups according to tertiles of the first 7-day energy achievement rate calculated using administered energy doses and basement energy expenditure. Skeletal muscle area (SMA) and changes in SMA were determined by CT on ICU admission and within days 7-10 of ICU admission. SMA maintenance was defined as SMA change ≥ 100%. Logistic regression analyses were performed to analyze the association of energy achievement rate with SMA changes (primary outcome) and in-hospital 28-day mortality (secondary outcome). RESULTS: Patients (n = 93) were classified into low, middle, and high groups according to their 7-day energy achievement rate (median rates, 16.8%, 38.8%, and 73.4%, respectively). The CT scans showed that SMA decreased between the CT scans in the low and middle groups, whereas it was maintained in the high group (median changes, -8.5%, -11.7%, and 2.8%, respectively). Univariate and multivariate logistic regression analyses showed that high energy achievement rate was significantly associated with SMA maintenance (reference, middle energy achieved group; univariate, odds ratio [95% confidence interval] 6.23 [2.04-19.10], P = 0.0013; multivariate, odds ratio [95% confidence interval] 5.92 [1.90-18.40], P = 0.0021). There was no significant difference in the association between energy achievement rate and mortality among the three groups. CONCLUSIONS: Our study found that a fulfillment of energy achievement in the first 7 days of hospitalization was associated with maintenance of muscle area. Thus, satisfying adequate energy should be considered even in patients with sepsis.

4.
In Vivo ; 38(2): 826-832, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38418116

RESUMO

BACKGROUND/AIM: Esophagogastroduodenoscopy (EGD) is an effective screening method for early detection of gastric cancer. The GAGLESS mouthpiece has a structure that widens the pharyngeal cavity and suppresses the pharyngeal reflex. This study aimed to investigate the acceptability, safety, and feasibility of transnasal and peroral ultrathin endoscopy using GAGLESS mouthpieces (Clinical Trial Number: UMIN000036922). PATIENTS AND METHODS: This study was a multicenter, prospective, randomized, open-label trial performed using a questionnaire. The study included 101 consecutive patients who visited the participating medical institutions between June 2019 and March 2022 (median age=47 years, range=24-87 years; all male). Patients aged ≥20 years at the time of consent acquisition who were the first to undergo EGD were included in the study. The primary endpoint was the degree of distress during EGD, as determined using a visual analog scale (VAS). RESULTS: The VAS score during endoscopic passage through the pharynx was significantly better in the transnasal endoscopy group than in the oral endoscopy group (2.420 vs. 4.092, p=0.001). There was no significant difference in the VAS scores between the two groups during anesthesia or throughout the examination. Compared with nasal endoscopy, oral endoscopy with a GAGLESS mouthpiece did not reduce the VAS score but did significantly improve gastric visibility. CONCLUSION: For patients in whom there was difficulty in inserting a nasal endoscope, using a GAGLESS mouthpiece rather than a conventional mouthpiece may be more useful in reducing pain.


Assuntos
Endoscopia Gastrointestinal , Dor , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estudos de Viabilidade , Estômago
5.
Biol Pharm Bull ; 47(2): 469-477, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38383000

RESUMO

Polyethylene glycol (PEG)-modified (PEGylated) cationic liposomes are frequently used as delivery vehicles for small interfering RNA (siRNA)-based drugs because of their ability to encapsulate/complex with siRNA and prolong the circulation half-life in vivo. Nevertheless, we have reported that subsequent intravenous (IV) injections of siRNA complexed with PEGylated cationic liposomes (PLpx) induces the production of anti-PEG immunoglobulin M (IgM), which accelerates the blood clearance of subsequent doses of PLpx and other PEGylated products. In this study, it is interesting that splenectomy (removal of spleen) did not prevent anti-PEG IgM induction by IV injection of PLpx. This indicates that B cells other than the splenic version are involved in anti-PEG IgM production under these conditions. In vitro and in vivo studies have shown that peritoneal cells also secrete anti-PEG IgM in response to the administration of PLpx. Interleukin-6 (IL-6) is a glycoprotein that is secreted by peritoneal immune cells and has been detected in response to the in vivo administration of PLpx. These observations indicate that IV injection of PLpx stimulates the proliferation/differentiation of peritoneal PEG-specific B cells into plasma cells via IL-6 induction, which results in the production of anti-PEG IgM from the peritoneal cavity of mice. Our results suggest the mutual contribution of peritoneal B cells as a potent anti-PEG immune response against PLpx.


Assuntos
Lipossomos , Polietilenoglicóis , Camundongos , Animais , RNA Interferente Pequeno , Imunoglobulina M , Interleucina-6
7.
Faraday Discuss ; 250(0): 361-376, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-37969106

RESUMO

A good solution for energy harvesting is to generate electricity using waste heat from our bodies or living environment. Therefore, the development of flexible and lightweight thermoelectric generators (TEGs) is urgently necessary, and studies on organic thermoelectric materials have become increasingly intensive. This article will present ongoing studies about a mysterious phenomenon in organic semiconductors, the giant Seebeck effect (GSE). The GSE was first discovered with pure C60 thin films and eventually confirmed to occur in various organic semiconductors. In the thin films or single crystals of organic small-molecule semiconductors with high purity, i.e., small carrier density, huge Seebeck coefficients, >0.1 V K-1, were reproducibly observed in the temperature range near 300-400 K. The facts revealed by the experiments to date will be presented, and unresolved mysteries will be discussed.

8.
Korean Circ J ; 53(11): 727-743, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37973385

RESUMO

Although cardiac rehabilitation (CR) has been shown to improve exercise tolerance and prognosis in patients with cardiovascular diseases, there remains low participation in outpatient CR. This may be attributed to the patients' busy schedules and difficulty in visiting the hospital due to distance, cost, avoidance of exercise, and severity of coronary disease. To overcome these challenges, many countries are exploring the possibility of remote CR. Specifically, there is increasing attention on the development of remote CR devices, which allow transmission of vital information to the hospital via a remote CR application linked to a wearable device for telemonitoring by dedicated hospital staff. In addition, remote CR programs can support return to work after hospitalization. Previous studies have demonstrated the effects of remote CR on exercise tolerance. However, the preventive effects of remote CR on cardiac events and mortality remain controversial. Thus, safe and effective remote CR requires exercise risk stratification for each patient, telenursing by skilled staff, and multidisciplinary interventions. Therefore, quality assurance of telenursing and multi-disciplinary interventions will be essential for remote CR. Remote CR may become an important part of cardiac management in the future. However, issues such as cost-effectiveness and insurance coverage still persist.

9.
J Intensive Care ; 11(1): 47, 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37932849

RESUMO

Providing standardized, high-quality rehabilitation for critically ill patients is a crucial issue. In 2017, the Japanese Society of Intensive Care Medicine (JSICM) promulgated the "Evidence-Based Expert Consensus for Early Rehabilitation in the Intensive Care Unit" to advocate for the early initiation of rehabilitations in Japanese intensive care settings. Building upon this seminal work, JSICM has recently conducted a rigorous systematic review utilizing the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology. This endeavor resulted in the formulation of Clinical Practice Guidelines (CPGs), designed to elucidate best practices in early ICU rehabilitation. The primary objective of this guideline is to augment clinical understanding and thereby facilitate evidence-based decision-making, ultimately contributing to the enhancement of patient outcomes in critical care settings. No previous CPGs in the world has focused specifically on rehabilitation of critically ill patients, using the GRADE approach. Multidisciplinary collaboration is extremely important in rehabilitation. Thus, the CPGs were developed by 73 members of a Guideline Development Group consisting of a working group, a systematic review group, and an academic guideline promotion group, with the Committee for the Clinical Practice Guidelines of Early Mobilization and Rehabilitation in Intensive Care of the JSICM at its core. Many members contributed to the development of the guideline, including physicians and healthcare professionals with multiple and diverse specialties, as well as a person who had been patients in ICU. Based on discussions among the group members, eight important clinical areas of focus for this CPG were identified. Fourteen important clinical questions (CQs) were then developed for each area. The public was invited to comment twice, and the answers to the CQs were presented in the form of 10 GRADE recommendations and commentary on the four background questions. In addition, information for each CQ has been created as a visual clinical flow to ensure that the positioning of each CQ can be easily understood. We hope that the CPGs will be a useful tool in the rehabilitation of critically ill patients for multiple professions.

10.
Cell Rep ; 42(9): 113035, 2023 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-37616163

RESUMO

Most gastrointestinal stromal tumors (GISTs) develop due to gain-of-function mutations in the tyrosine kinase gene, KIT. We recently showed that mutant KIT mislocalizes to the Golgi area and initiates uncontrolled signaling. However, the molecular mechanisms underlying its Golgi retention remain unknown. Here, we show that protein kinase D2 (PKD2) is activated by the mutant, which causes Golgi retention of KIT. In PKD2-inhibited cells, KIT migrates from the Golgi region to lysosomes and subsequently undergoes degradation. Importantly, delocalized KIT cannot trigger downstream activation. In the Golgi/trans-Golgi network (TGN), KIT activates the PKD2-phosphatidylinositol 4-kinase IIIß (PKD2-PI4KIIIß) pathway through phospholipase Cγ2 (PLCγ2) to generate a PI4P-rich membrane domain, where the AP1-GGA1 complex is aberrantly recruited. Disruption of any factors in this cascade results in the release of KIT from the Golgi/TGN. Our findings show the molecular mechanisms underlying KIT mislocalization and provide evidence for a strategy for inhibition of oncogenic signaling.


Assuntos
Tumores do Estroma Gastrointestinal , Humanos , Tumores do Estroma Gastrointestinal/genética , Tumores do Estroma Gastrointestinal/metabolismo , Tumores do Estroma Gastrointestinal/patologia , Proteína Quinase D2 , Fosfolipase C gama/metabolismo , Complexo de Golgi/metabolismo , Rede trans-Golgi/metabolismo , Proteínas Proto-Oncogênicas c-kit/metabolismo
11.
RSC Adv ; 13(32): 22226-22233, 2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37492513

RESUMO

Doping control of carbon nanotube (CNT) is crucial for thermoelectric (TE) application to maximize the power conversion efficiency. Despite the recent achievement of good air stability by organic salts for n-type carrier doping, their doping mechanism has not been systematically investigated so far. Here, we demonstrate doping of CNT yarn using ammonium salts with different halogen elements (tetra-butylammonium salts, TBAX where X = Cl, Br, or I) through the dipping technique. By changing the halogen element, we specifically investigated the halogen effect in the n-type doping process of CNT. The introduction of each material into the CNT yarn and its doping reaction were then studied by energy-dispersive X-ray spectroscopy and X-ray photoelectron spectroscopy. Halogen element was found to affect the excess amount of TBA+ cation in the CNT yarn. The largest amount of excess TBA+ is found in the TBAI-doped yarn, which stabilizes the most amount of negative charge in CNT, enhancing the TE performance and its stability over one month in air. This study discovers the importance of the halogen element in the doping process of CNT-based TE materials by organic salts, simultaneously offering an efficient and stable n-type doping strategy.

12.
Artigo em Inglês | MEDLINE | ID: mdl-36893168

RESUMO

Parsonage-Turner syndrome (PTS) is a peripheral neuropathy involving the brachial plexus very rare in childhood. To date, no cases of PTS after COVID-19 vaccination have been reported in children. We report a case of a 15-year-old boy affected by PTS after the second dose of the BNT162b2 (Comirnaty, Pfizer-BioNTech) COVID-19 vaccine.


Assuntos
Neurite do Plexo Braquial , COVID-19 , Masculino , Humanos , Criança , Adolescente , Neurite do Plexo Braquial/etiologia , Vacinas contra COVID-19/efeitos adversos , Vacina BNT162 , COVID-19/prevenção & controle , Vacinação/efeitos adversos
13.
Intern Med ; 62(9): 1305-1309, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36104196

RESUMO

Platypnea-orthodeoxia syndrome (POS) is a rare disease characterized by dyspnea and hypoxemia in orthostatism that improves in the recumbent position. We herein report an 81-year-old woman with dyspnea in the upright position following thoracic vertebral compression fractures. After the patient's daughter brought a recording showing decreasing SpO2 (peripheral capillary oxygen saturation) in the upright position as measured by a portable pulse oximeter outside the hospital, a small atrial septal defect (ASD) was detected. A contrast echocardiogram and four-dimensional flow magnetic resonance imaging demonstrated a right-to-left shunt. The patient's symptoms dramatically improved after percutaneous ASD closure. In conclusion, such new technologies are useful for diagnosing POS.


Assuntos
Forame Oval Patente , Fraturas por Compressão , Comunicação Interatrial , Fraturas da Coluna Vertebral , Feminino , Humanos , Idoso de 80 Anos ou mais , Síndrome de Platipneia Ortodeoxia , Postura , Comunicação Interatrial/diagnóstico , Comunicação Interatrial/diagnóstico por imagem , Oxigênio , Hipóxia/diagnóstico , Hipóxia/etiologia , Dispneia/diagnóstico , Dispneia/etiologia , Forame Oval Patente/diagnóstico , Forame Oval Patente/diagnóstico por imagem
14.
Rom J Intern Med ; 60(3): 193-196, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35599545

RESUMO

A 59-year-old man who had smoked for 23 pack-years was admitted to our hospital because of two-month history of back pain. The chest computed tomography scan demonstrated combined pulmonary fibrosis and emphysema (CPFE) and an irregular shaped nodule in the left lower lobe of the lung. A biopsy obtained from samples from subcarinal lymph nodes revealed non-small cell lung cancer. Anti-aminoacyl-tRNA synthetase (ARS) antibody was elevated up to 166 U/mL, although he had no symptoms suggestive connective tissue diseases. It is well known that most of CPFE patients are current or former heavy smokers, and some researchers described the relationship between CPFE and connective tissue diseases. To our best knowledge, this was the first report of lung cancer in patient with anti-ARS antibody-positive CPFE. In some anti-ARS antibody-positive patients, smoking might have a relationship with development of CPFE and lung cancer.


Assuntos
Aminoacil-tRNA Sintetases , Carcinoma Pulmonar de Células não Pequenas , Doenças do Tecido Conjuntivo , Enfisema , Neoplasias Pulmonares , Enfisema Pulmonar , Fibrose Pulmonar , Carcinoma Pulmonar de Células não Pequenas/complicações , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Humanos , Neoplasias Pulmonares/complicações , Masculino , Pessoa de Meia-Idade , Enfisema Pulmonar/complicações , Enfisema Pulmonar/diagnóstico por imagem , Fibrose Pulmonar/complicações , Fibrose Pulmonar/diagnóstico por imagem , Estudos Retrospectivos
16.
Sci Rep ; 11(1): 22678, 2021 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-34811450

RESUMO

FMS-like tyrosine kinase 3 (FLT3) in hematopoietic cells binds to its ligand at the plasma membrane (PM), then transduces growth signals. FLT3 gene alterations that lead the kinase to assume its permanently active form, such as internal tandem duplication (ITD) and D835Y substitution, are found in 30-40% of acute myelogenous leukemia (AML) patients. Thus, drugs for molecular targeting of FLT3 mutants have been developed for the treatment of AML. Several groups have reported that compared with wild-type FLT3 (FLT3-wt), FLT3 mutants are retained in organelles, resulting in low levels of PM localization of the receptor. However, the precise subcellular localization of mutant FLT3 remains unclear, and the relationship between oncogenic signaling and the mislocalization is not completely understood. In this study, we show that in cell lines established from leukemia patients, endogenous FLT3-ITD but not FLT3-wt clearly accumulates in the perinuclear region. Our co-immunofluorescence assays demonstrate that Golgi markers are co-localized with the perinuclear region, indicating that FLT3-ITD mainly localizes to the Golgi region in AML cells. FLT3-ITD biosynthetically traffics to the Golgi apparatus and remains there in a manner dependent on its tyrosine kinase activity. Tyrosine kinase inhibitors, such as quizartinib (AC220) and midostaurin (PKC412), markedly decrease FLT3-ITD retention and increase PM levels of the mutant. FLT3-ITD activates downstream in the endoplasmic reticulum (ER) and the Golgi apparatus during its biosynthetic trafficking. Results of our trafficking inhibitor treatment assays show that FLT3-ITD in the ER activates STAT5, whereas that in the Golgi can cause the activation of AKT and ERK. We provide evidence that FLT3-ITD signals from the early secretory compartments before reaching the PM in AML cells.


Assuntos
Proliferação de Células/genética , Leucemia Mieloide Aguda/metabolismo , Sistema de Sinalização das MAP Quinases/genética , Mutação , Sequências de Repetição em Tandem/genética , Tirosina Quinase 3 Semelhante a fms/biossíntese , Tirosina Quinase 3 Semelhante a fms/genética , Benzotiazóis/farmacologia , Membrana Celular/metabolismo , Proliferação de Células/efeitos dos fármacos , Retículo Endoplasmático/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Complexo de Golgi/metabolismo , Humanos , Leucemia Mieloide Aguda/patologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Oncogenes , Compostos de Fenilureia/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fator de Transcrição STAT5/metabolismo , Estaurosporina/análogos & derivados , Estaurosporina/farmacologia , Células THP-1 , Proteínas Supressoras de Tumor/metabolismo , Tirosina Quinase 3 Semelhante a fms/antagonistas & inibidores
17.
ACS Appl Mater Interfaces ; 13(32): 38534-38543, 2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34357757

RESUMO

Layer-by-layer fabrication of uniformly oriented thin films over large areas by cost-effective solution-based approaches can open new horizons for the realization of high-performance organic circuits in various applications. In this work, fabrication of a large-area ≈40 cm2 film with uniform orientation is reported for poly(3,3‴-dialkylquaterthiophene) (PQT) using a unidirectional floating film transfer method (UFTM). Orientation characteristics and charge transport anisotropy were analyzed using polarized UV-vis spectral mapping and fabrication of bottom-gated organic field-effect transistors (OFETs) from different regions. Films were found to be highly oriented with an optical dichroic ratio of ca. 15. Orientation characteristics reveal that films were highly oriented along the width of the film, covering >70% of the area, and angle-dependent field-effect mobilities are in good agreement with the orientation of the polymer backbones. These highly oriented films resulted in charge transport anisotropy of 8.9. An array of bottom-gated OFETs fabricated along the length of single large-area (≈15 × 2.5 cm2) thin film demonstrated the average field-effect mobility of 0.0262 cm2/(V s) with a very narrow standard deviation of 12.6%. We also demonstrated that film thickness can be easily tuned from 5.6 to 45 nm by increasing the PQT concentration, and field-effect mobility is highly reproducible even when the film thickness is 10 nm. Microstructural characterization of the thus-prepared large-area thin films revealed the edge-on stacked polymer backbones and surface roughness of <1 nm as probed by grazing incidence X-ray diffraction and atomic force microscopy, respectively. Flexible OFETs with bottom-gate top-contact geometry were also fabricated, having average field-effect mobility of 0.0181 cm2/(V s). There was no considerable change in mobility after bending the flexible devices at different radii.

18.
Biol Pharm Bull ; 44(5): 642-652, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33658452

RESUMO

Radiation is an effective cancer treatment, but cancer cells can acquire radioresistance, which is associated with increased DNA damage response and enhanced proliferative capacity, and therefore, it is important to understand the intracellular biochemical responses to γ-irradiation. The transient receptor potential melastatin 8 (TRPM8) channel plays roles in the development and progression of tumors, but it is unclear whether it is involved in the DNA damage response induced by γ-irradiation. Here, we show that a TRPM8 channel inhibitor suppresses the DNA damage response (phosphorylated histone variant H2AX-p53-binding protein 1 (γH2AX-53BP1) focus formation) and colony formation of B16 melanoma cells. Furthermore, the TRPM8 channel-specific agonist WS-12 enhanced the DNA damage response and increased the survival fraction after γ-irradiation. We found that the TRPM8 channel inhibitor enhanced G2/M phase arrest after γ-irradiation. Phosphorylation of ataxia telangiectasia mutated and p53, which both contribute to the DNA damage response was also suppressed after γ-irradiation. In addition, the TRPM8 channel inhibitor enhanced the γ-irradiation-induced suppression of tumor growth in vivo. We conclude that the TRPM8 channel is involved in radiation-induced DNA damage repair and contributes to the radioresistance of B16 melanoma cells. TRPM8 channel inhibitors might be clinically useful as radiosensitizers to enhance radiation therapy of melanoma.


Assuntos
Dano ao DNA , Reparo do DNA , Melanoma Experimental/radioterapia , Canais de Cátion TRPM/metabolismo , Canais de Potencial de Receptor Transitório/metabolismo , Anilidas/farmacologia , Animais , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Linhagem Celular Tumoral , Raios gama , Histonas/metabolismo , Masculino , Melanoma Experimental/metabolismo , Proteínas de Membrana/metabolismo , Mentol/análogos & derivados , Mentol/farmacologia , Camundongos , Fosforilação , Radiossensibilizantes/farmacologia , Proteína Supressora de Tumor p53/metabolismo , Proteína 1 de Ligação à Proteína Supressora de Tumor p53/metabolismo
19.
Mol Immunol ; 131: 51-59, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33386150

RESUMO

During T-cell regulation, T-cell receptors and CD28 lead to signaling activation, while T-lymphocyte antigen 4 (CTLA-4) is known to lead to downregulation, similar to programmed cell death-1 (PD-1). In the cytoplasmic tails of CD28 and CTLA-4, phosphoinositide 3-kinase (PI3K) binds to the consensus sequence including phosphotyrosine via SH2 domains, N- and C-terminal SH2 domains (nSH2 and cSH2), of its regulatory subunit, p85. In this study, we determined the crystal structure of a CTLA-4-derived phosphopeptide in complex with a Cys-substituted mutant of cSH2, C656S/C659V/C670L, at a 1.1 Å resolution. Phosphotyrosine of the bound peptide is tightly accommodated by the residues Arg631, Arg649, Ser651, and Ser652, similar to the cSH2 wild-type recognition mode of CD28, as reported previously. Upon the Cys mutation, the cSH2 thermal stability increased while the CTLA-4 binding affinity slightly changed. The binding experiments also showed that the binding affinity of CTLA-4 by cSH2 was approximately two orders of magnitude lower than that of CD28. Similar to CD28 binding, the CTLA-4 binding affinity of nSH2 was lower than that of cSH2. The complex structure of nSH2 and CTLA-4 was modeled, and compared with the crystal structure of cSH2 mutant and CTLA-4. The difference in the binding affinity between CD28 and CTLA-4, along with the difference between nSH2 and cSH2, could be explained by the 3D structures, which would be closely correlated with the respective T-cell signaling.


Assuntos
Antígeno CTLA-4/metabolismo , Citoplasma/metabolismo , Fosfatidilinositol 3-Quinase/metabolismo , Domínios de Homologia de src/fisiologia , Sequência de Aminoácidos , Antígenos CD28/metabolismo , Escherichia coli/metabolismo , Mutação/genética , Fosfopeptídeos/metabolismo , Transdução de Sinais/fisiologia , Linfócitos T/metabolismo
20.
Antioxidants (Basel) ; 10(1)2021 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-33466842

RESUMO

Resistance training adaptively increases the muscle strength associated with protein anabolism. Previously, we showed that the combined intake of astaxanthin, ß-carotene, and resveratrol can accelerate protein anabolism in the skeletal muscle of mice. The purpose of this study was to investigate the effect of anabolic nutrient-rich foods on muscle adaptation induced by resistance training. Twenty-six healthy men were divided into control and intervention groups. All participants underwent a resistance training program twice a week for 10 weeks. Astaxanthin-, ß-carotene-, and resveratrol-rich foods were provided to the intervention group. Body composition, nutrient intake, maximal voluntary contraction of leg extension, oxygen consumption, and serum carbonylated protein level were measured before and after training. The skeletal muscle mass was higher after training than before training in both groups (p < 0.05). Maximal voluntary contraction was increased after training in the intervention group (p < 0.05), but not significantly increased in the control group. Resting oxygen consumption was higher after training in the intervention group only (p < 0.05). As an oxidative stress marker, serum carbonylated protein level tended to be lower immediately after exercise than before exercise in the intervention group only (p = 0.056). Intake of astaxanthin-, ß-carotene-, and resveratrol-rich foods supported resistance training-induced strength and metabolic adaptations.

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