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1.
Cell Metab ; 36(9): 2156-2166.e9, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39111307

RESUMO

Choline is an essential nutrient for the biosynthesis of phospholipids, neurotransmitters, and one-carbon metabolism with a critical step being its import into mitochondria. However, the underlying mechanisms and biological significance remain poorly understood. Here, we report that SLC25A48, a previously uncharacterized mitochondrial inner-membrane carrier protein, controls mitochondrial choline transport and the synthesis of choline-derived methyl donors. We found that SLC25A48 was required for brown fat thermogenesis, mitochondrial respiration, and mitochondrial membrane integrity. Choline uptake into the mitochondrial matrix via SLC25A48 facilitated the synthesis of betaine and purine nucleotides, whereas loss of SLC25A48 resulted in increased production of mitochondrial reactive oxygen species and imbalanced mitochondrial lipids. Notably, human cells carrying a single nucleotide polymorphism on the SLC25A48 gene and cancer cells lacking SLC25A48 exhibited decreased mitochondrial choline import, increased oxidative stress, and impaired cell proliferation. Together, this study demonstrates that SLC25A48 regulates mitochondrial choline catabolism, bioenergetics, and cell survival.


Assuntos
Colina , Mitocôndrias , Colina/metabolismo , Humanos , Mitocôndrias/metabolismo , Animais , Camundongos , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Proteínas de Transporte da Membrana Mitocondrial/genética , Transporte Biológico , Camundongos Endogâmicos C57BL , Masculino , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Termogênese/genética
2.
Biol Open ; 13(1)2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38156558

RESUMO

Historically, necrosis has been considered a passive process, which is induced by extreme stress or damage. However, recent findings of necroptosis, a programmed form of necrosis, shed a new light on necrosis. It has been challenging to detect necrosis reliably in vivo, partly due to the lack of genetically encoded sensors to detect necrosis. This is in stark contrast with the availability of many genetically encoded biosensors for apoptosis. Here we developed Necrosensor, a genetically encoded fluorescent sensor that detects necrosis in Drosophila, by utilizing HMGB1, which is released from the nucleus as a damage-associated molecular pattern (DAMP). We demonstrate that Necrosensor is able to detect necrosis induced by various stresses in multiple tissues in both live and fixed conditions. Necrosensor also detects physiological necrosis that occurs during spermatogenesis in the testis. Using Necrosensor, we discovered previously unidentified, physiological necrosis of hemocyte progenitors in the hematopoietic lymph gland of developing larvae. This work provides a new transgenic system that enables in vivo detection of necrosis in real time without any intervention.


Assuntos
Técnicas Biossensoriais , Drosophila , Masculino , Animais , Drosophila/genética , Necrose , Apoptose , Espermatogênese
3.
EMBO J ; 42(12): e111383, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37140455

RESUMO

Cancer exerts pleiotropic, systemic effects on organisms, leading to health deterioration and eventually to organismal death. How cancer induces systemic effects on remote organs and the organism itself still remains elusive. Here we describe a role for NetrinB (NetB), a protein with a particularly well-characterized role as a tissue-level axon guidance cue, in mediating oncogenic stress-induced organismal, metabolic reprogramming as a systemic humoral factor. In Drosophila, Ras-induced dysplastic cells upregulate and secrete NetB. Inhibition of either NetB from the transformed tissue or its receptor in the fat body suppresses oncogenic stress-induced organismal death. NetB from the dysplastic tissue remotely suppresses carnitine biosynthesis in the fat body, which is critical for acetyl-CoA generation and systemic metabolism. Supplementation of carnitine or acetyl-CoA ameliorates organismal health under oncogenic stress. This is the first identification, to our knowledge, of a role for the Netrin molecule, which has been studied extensively for its role within tissues, in humorally mediating systemic effects of local oncogenic stress on remote organs and organismal metabolism.


Assuntos
Proteínas de Drosophila , Drosophila , Animais , Drosophila/metabolismo , Netrinas/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Acetilcoenzima A/metabolismo , Transdução de Sinais , Axônios/metabolismo , Fatores de Crescimento Neural/metabolismo
4.
Int J Qual Health Care ; 34(1)2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35024823

RESUMO

BACKGROUND: Contrast media agents are essential for computed tomography (CT)-based diagnoses. However, they can cause fatal adverse effects such as anaphylaxis in patients. Although it is rare, the chances of anaphylaxis increase with the number of examinations. OBJECTIVE: We aimed to design a quality improvement initiative to reduce patient risk to contrast media agents. METHODS: We analysed CT processes using contrast iodine in a tertiary-care academic hospital that performs approximately 14 000 CT scans per year in Japan. We applied a combination of failure modes and effects analysis (FMEA) and cause-effect analysis to reduce the risk of patients developing allergic reactions to iodine-based contrast agents during CT imaging. RESULTS: Our multidisciplinary team comprising seven professionals analysed the data and designed a 56-process flowchart of CT imaging with iodine. We obtained 177 failure modes, of which 15 had a risk-probability number higher than 100. We identified the two riskiest processes and developed cause-and-effect diagrams for both: one was related to the exchange of information between the radiation and hospital information system regarding the patient's allergy, the other was due to education and structural deficiencies in observation following the exam. CONCLUSION: The combined method of FMEA and cause-and-effect analysis reveals high-risk processes and suggests measures to reduce these risks. FMEA is not well-known in healthcare but has significant potential for improving patient safety. Our findings emphasise the importance of adopting new techniques to reduce patient risk and carry out best practices in radiology.


Assuntos
Anafilaxia , Análise do Modo e do Efeito de Falhas na Assistência à Saúde , Anafilaxia/induzido quimicamente , Anafilaxia/prevenção & controle , Meios de Contraste/efeitos adversos , Humanos , Segurança do Paciente , Medição de Risco
5.
Anal Chem ; 94(2): 944-951, 2022 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-34962382

RESUMO

We have developed a one-step method to isolate protein C-terminal peptides from V8 protease-digested proteins by metal oxide-based ligand-exchange (MOLEX) chromatography. V8 protease cleaves the C-terminal side of Asp and Glu, affording a digested peptide with two carboxy groups at the C-terminus, whereas the protein C-terminal peptide has only one α-carboxy group. In MOLEX chromatography, a stable chelate is formed between dicarboxylates and metal atoms, so that the nonterminal (i.e., internal) peptide is retained, whereas the protein C-terminal peptide flows through the MOLEX column. After the optimization of the MOLEX chromatographic conditions, 1619 protein C-termini were identified from 30 µg of peptides (10 µg each, in triplicate) derived from human HeLa cells by means of nanoLC/MS/MS. When the MOLEX-isolated sample from 200 µg of HeLa peptides was further divided into six fractions by high-pH reversed-phase liquid chromatography (LC) prior to nanoLC/MS/MS, 2203 protein C-termini were identified with less than 3% contamination with internal peptides. We believe that this is the largest coverage with the highest purity reported to date in human protein C-terminomics. This fast, simple, sensitive, and selective method to isolate protein C-terminal peptides should be useful for profiling protein C-termini on a proteome-wide scale.


Assuntos
Proteína C , Espectrometria de Massas em Tandem , Cromatografia de Fase Reversa , Células HeLa , Humanos , Ligantes , Óxidos , Peptídeo Hidrolases , Peptídeos/química , Espectrometria de Massas em Tandem/métodos
6.
Elife ; 102021 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-33902813

RESUMO

Oncogenes often promote cell death as well as proliferation. How oncogenes drive these diametrically opposed phenomena remains to be solved. A key question is whether cell death occurs as a response to aberrant proliferation signals or through a proliferation-independent mechanism. Here, we reveal that Src, the first identified oncogene, simultaneously drives cell proliferation and death in an obligatorily coupled manner through parallel MAPK pathways. The two MAPK pathways diverge from a lynchpin protein Slpr. A MAPK p38 drives proliferation whereas another MAPK JNK drives apoptosis independently of proliferation signals. Src-p38-induced proliferation is regulated by methionine-mediated Tor signaling. Reduction of dietary methionine uncouples the obligatory coupling of cell proliferation and death, suppressing tumorigenesis and tumor-induced lethality. Our findings provide an insight into how cells evolved to have a fail-safe mechanism that thwarts tumorigenesis by the oncogene Src. We also exemplify a diet-based approach to circumvent oncogenesis by exploiting the fail-safe mechanism.


Assuntos
Morte Celular , Proliferação de Células , Proteínas de Drosophila/genética , Drosophila melanogaster/fisiologia , Metionina/deficiência , Proteínas Proto-Oncogênicas pp60(c-src)/genética , Animais , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Drosophila melanogaster/crescimento & desenvolvimento , Larva/genética , Larva/crescimento & desenvolvimento , Larva/fisiologia , Proteínas Proto-Oncogênicas pp60(c-src)/metabolismo
7.
J Gastroenterol ; 56(4): 323-335, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33710392

RESUMO

BACKGROUND: The Japanese Society of Gastroenterology (JSGE) published ''Daicho Polyp Shinryo Guideline 2014'' in Japanese and a part of this guideline was published in English as "Evidence-based clinical practice guidelines for management of colorectal polyps" in the Journal of Gastroenterology in 2015. A revised version of the Japanese-language guideline was published in 2020, and here we introduce a part of the contents of revised version. METHODS: The guideline committee discussed and drew up a series of clinical questions (CQs). Recommendation statements for the CQs were limited to items with multiple therapeutic options. Items with established conclusions that had 100% agreement with previous guidelines (background questions) and items with no (or old) evidence that are topics for future research (future research questions: FRQs) were given descriptions only. To address the CQs and FRQs, PubMed, ICHUSHI, and other sources were searched for relevant articles published in English from 1983 to October 2018 and articles published in Japanese from 1983 to November 2018. The Japan Medical Library Association was also commissioned to search for relevant materials. Manual searches were performed for questions with insufficient online references. RESULTS: The professional committee created 18 CQs and statements concerning the current concept and diagnosis/treatment of various colorectal polyps, including their epidemiology, screening, pathophysiology, definition and classification, diagnosis, management, practical treatment, complications, and surveillance after treatment, and other colorectal lesions (submucosal tumors, nonneoplastic polyps, polyposis, hereditary tumors, ulcerative colitis-associated tumors/carcinomas). CONCLUSIONS: After evaluation by the moderators, evidence-based clinical practice guidelines for management of colorectal polyps were proposed for 2020. This report addresses the therapeutic related CQs introduced when formulating these guidelines.


Assuntos
Pólipos do Colo/terapia , Guias como Assunto/normas , Gerenciamento Clínico , Prática Clínica Baseada em Evidências , Humanos , Japão
9.
BMJ Open ; 9(9): e026002, 2019 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-31542733

RESUMO

OBJECTIVES: Recent meta-analyses of eradication therapy in Helicobacter pylori-infected adults reported significant reductions in gastric carcinoma risk. However, concerns about supporting unfocused screening and eradication programme in healthy, asymptomatic populations have arisen. We performed a systematic review and Bayesian meta-analysis to provide an accurate interpretation of randomised evidence on the preventive effectiveness of eradication therapy on gastric carcinoma risk. METHODS: We searched databases including PubMed, Cochrane Central and Embase for reference and citation tracking without language restrictions, from inception through 31 July 2018. Paired investigators independently selected randomised controlled trials (RCTs) comparing eradication therapy with placebo or no treatment for asymptomatic or dyspeptic H. pylori-infected adults with no previous gastric carcinoma. The main outcome was gastric carcinoma incidence; secondary outcomes included gastric carcinoma-specific, non-gastric carcinoma and all-cause mortality. RESULTS: A total of 5 population-based and 2 outpatient care-based RCTs involving 7303 adults were eligible. Eradication algorithms were heterogeneous, and unsuccessful eradication and reinfection were frequently observed. A Bayesian meta-analysis with competing risk outcomes found low-certainty evidence that eradication therapy might be more likely than control to reduce gastric carcinoma risk (HR=0.65; 95% credible interval (CrI) 0.41 to 1.0; I2 =11%). The CrIs included the null effects across the subgroup and sensitivity analyses, apart from those based on particular models that excluded two RCTs that enrolled subjects with specific histological findings only (HR=0.55; CrI 0.30 to 0.89; I2 =14%). The uncertainty of the average 41% risk reduction in gastric carcinoma-specific mortality included a clinically important mortality risk increase (HR=0.59 favouring eradication therapy; CrI 0.25 to 1.20; I2 =13%; low certainty). CONCLUSIONS: There is insufficient evidence to support or refute the effectiveness of eradication therapy in preventing gastric carcinoma in H. pylori-infected, high-risk populations. Rigorously conducted large RCTs of healthy infected adults only would provide evidence of the true efficacy of successful eradication. PROSPERO registration number: CRD42014009245.


Assuntos
Infecções Assintomáticas , Infecções por Helicobacter/tratamento farmacológico , Neoplasias Gástricas/prevenção & controle , Adulto , Teorema de Bayes , Infecções por Helicobacter/complicações , Helicobacter pylori , Humanos , Avaliação de Processos e Resultados em Cuidados de Saúde , Ensaios Clínicos Controlados Aleatórios como Assunto , Neoplasias Gástricas/microbiologia
10.
Ann N Y Acad Sci ; 1457(1): 158-165, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31452205

RESUMO

Squalene is a terpenoid found in human skin surface lipids (SSLs) and foods that possesses beneficial properties. However, since oxidation of squalene causes various complications, it is necessary to identify the mechanisms by which squalene is oxidized. In this study, we aimed to determine the oxidation mechanisms of squalene in SSLs and shark liver oil (SLO) supplements by the analysis of squalene monohydroperoxide (SQOOH) isomers, on the basis of our previous finding that different oxidation mechanisms yield different SQOOH isomers. Liquid chromatography-tandem mass spectrometry analysis of SQOOH isomers revealed that squalene in human SSLs was oxidized by singlet oxygen oxidation, whereas squalene in SLO was oxidized mainly by free radicals. As a result, we have presented the first evidence suggesting that the analysis of SQOOH isomers enables estimation of oxidation mechanisms. Estimating oxidation mechanisms by analyzing SQOOH isomers may provide a foundation for the prevention of skin diseases and food deterioration via regulation of squalene oxidation.


Assuntos
Gorduras Insaturadas na Dieta/metabolismo , Lipídeos/química , Fígado/metabolismo , Oxigênio/metabolismo , Pele/metabolismo , Esqualeno/metabolismo , Animais , Cromatografia Líquida , Suplementos Nutricionais , Testa , Radicais Livres , Voluntários Saudáveis , Humanos , Espectrometria de Massas , Oxirredução , Tubarões , Esqualeno/análogos & derivados
11.
Nutr Cancer ; 71(7): 1153-1164, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31179755

RESUMO

Many functional foods or physiologically active ingredients derived from plants and animals are actively being investigated for their role in chronic disease prevention. Squalene (SQ) is found as active ingredient in the functional foods predominantly present in olive oil and shark liver oil. It is known that during chemotherapy anticancer drugs induce inflammation. SQ has been thought to prevent and suppress inflammation; however, there is little direct evidence available. We examined the adjuvant effect of SQ on tumor-transplanted mice along with anticancer drug doxorubicin (DOX). SQ significantly suppressed the DOX-induced increase in prostaglandin E2 (PGE2) concentration (P < 0.05) in plasma of tumor-bearing mice. SQ inhibited the numbers of writhing response (P < 0.05), formalin-induced pain and decreased COX-2 and substance P expression in the tumor tissue compared to control mice and also enhanced the antitumor efficacy of DOX in allograft mice. Thus, SQ reduces inflammation through modulation of PGE2 production indicating its potential as an adjuvant during chemotherapy in tumor-bearing mice.


Assuntos
Analgésicos/farmacologia , Anti-Inflamatórios não Esteroides/farmacologia , Alimento Funcional , Esqualeno/farmacologia , Aloenxertos , Ração Animal , Animais , Linhagem Celular Tumoral , Neoplasias do Colo/tratamento farmacológico , Ciclo-Oxigenase 2/metabolismo , Inibidores de Ciclo-Oxigenase 2/farmacologia , Dinoprostona/sangue , Doxorrubicina/administração & dosagem , Camundongos Endogâmicos BALB C , Esqualeno/administração & dosagem , Substância P/metabolismo
12.
Gen Thorac Cardiovasc Surg ; 67(6): 573-575, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31020479

RESUMO

In the original publication of the article, the values of the row "Norwood procedure", under "(3) Main procedure" in Table 3 were published incorrectly. The corrected part of the table is given in this Correction.

15.
Case Rep Gastroenterol ; 12(2): 425-431, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30186095

RESUMO

A 75-year-old male was admitted to our hospital because of bile duct stenosis. He had no medical history of autoimmune disease. The level of tumor markers, serum IgG, and IgG4 were within normal ranges. Computed tomography showed perihilar and distal bile duct stenosis and wall thickening without swelling or abnormal enhancement of the pancreas. Endoscopic retrograde cholangiopancreatography showed perihilar and distal bile duct stenosis. A biopsy and cytology from the distal bile duct stenosis suggested adenocarcinoma, and cytology from the perihilar bile duct also suggested adenocarcinoma. A preoperative diagnosis of perihilar and distal bile duct cancer was made, and the patient underwent left hepatectomy and pancreaticoduodenectomy. Resected specimens showed wall thickening in the perihilar and distal bile duct; however, tumors were unclear. A histopathological examination revealed lymphoplasmacytic infiltration, storiform fibrosis, and obliterative phlebitis in the perihilar and distal bile ducts. Immunohistochemistry revealed diffuse infiltration of IgG4-positive plasma cells in the perihilar and distal bile ducts. Lymphoplasmacytic infiltration, inflammatory change, storiform fibrosis, and obliterative phlebitis were shown in the pancreas. A final diagnosis of IgG4-related sclerosing cholangitis (IgG4-SC) with autoimmune pancreatitis was made. We herein report a case in which a preoperative diagnosis of IgG4-SC was difficult due to normal serum IgG4 levels and no obvious pancreatic lesion.

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