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1.
Mol Cell ; 81(2): 304-322.e16, 2021 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-33357414

RESUMO

Protein synthesis must be finely tuned in the developing nervous system as the final essential step of gene expression. This study investigates the architecture of ribosomes from the neocortex during neurogenesis, revealing Ebp1 as a high-occupancy 60S peptide tunnel exit (TE) factor during protein synthesis at near-atomic resolution by cryoelectron microscopy (cryo-EM). Ribosome profiling demonstrated Ebp1-60S binding is highest during start codon initiation and N-terminal peptide elongation, regulating ribosome occupancy of these codons. Membrane-targeting domains emerging from the 60S tunnel, which recruit SRP/Sec61 to the shared binding site, displace Ebp1. Ebp1 is particularly abundant in the early-born neural stem cell (NSC) lineage and regulates neuronal morphology. Ebp1 especially impacts the synthesis of membrane-targeted cell adhesion molecules (CAMs), measured by pulsed stable isotope labeling by amino acids in cell culture (pSILAC)/bioorthogonal noncanonical amino acid tagging (BONCAT) mass spectrometry (MS). Therefore, Ebp1 is a central component of protein synthesis, and the ribosome TE is a focal point of gene expression control in the molecular specification of neuronal morphology during development.


Assuntos
Proteínas de Ligação a DNA/genética , Regulação da Expressão Gênica no Desenvolvimento , Neocórtex/metabolismo , Neurônios/metabolismo , Biossíntese de Proteínas , Proteostase/genética , Proteínas de Ligação a RNA/genética , Subunidades Ribossômicas Maiores de Eucariotos/genética , Animais , Animais Recém-Nascidos , Sítios de Ligação , Moléculas de Adesão Celular Neuronais/química , Moléculas de Adesão Celular Neuronais/genética , Moléculas de Adesão Celular Neuronais/metabolismo , Linhagem Celular Tumoral , Microscopia Crioeletrônica , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/metabolismo , Embrião de Mamíferos , Feminino , Masculino , Camundongos , Neocórtex/citologia , Neocórtex/crescimento & desenvolvimento , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Neurogênese/genética , Neurônios/citologia , Cultura Primária de Células , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/metabolismo , Subunidades Ribossômicas Maiores de Eucariotos/metabolismo , Subunidades Ribossômicas Maiores de Eucariotos/ultraestrutura , Partícula de Reconhecimento de Sinal/química , Partícula de Reconhecimento de Sinal/genética , Partícula de Reconhecimento de Sinal/metabolismo
2.
Plant J ; 118(6): 2141-2153, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38558422

RESUMO

In angiosperms, cyclic electron transport around photosystem I (PSI) is mediated by two pathways that depend on the PROTON GRADIENT REGULATION 5 (PGR5) protein and the chloroplast NADH dehydrogenase-like (NDH) complex, respectively. In the Arabidopsis double mutants defective in both pathways, plant growth and photosynthesis are impaired. The pgr5-1 mutant used in the original study is a missense allele and accumulates low levels of PGR5 protein. In this study, we generated two knockout (KO) alleles, designated as pgr5-5 and pgr5-6, using the CRISPR-Cas9 technology. Although both KO alleles showed a severe reduction in P700 similar to the pgr5-1 allele, NPQ induction was less severely impaired in the KO alleles than in the pgr5-1 allele. In the pgr5-1 allele, the second mutation affecting NPQ size was mapped to ~21 cM south of the pgr5-1 locus. Overexpression of the pgr5-1 allele, encoding the glycine130-to-serine change, complemented the pgr5-5 phenotype, suggesting that the pgr5-1 mutation destabilizes PGR5 but that the mutant protein retains partial functionality. Using two KO alleles, we created the double mutants with two chlororespiratory reduction (crr) mutants defective in the NDH complex. The growth of the double mutants was notably impaired. In the double mutant seedlings that survived on the medium containing sucrose, PSI activity evaluated by the P700 oxidation was severely impaired, whereas PSII activity was only mildly impaired. Cyclic electron transport around PSI is required to maintain PSI activity.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Fotossíntese , Complexo de Proteínas do Centro de Reação Fotossintética , Complexo de Proteína do Fotossistema I , Complexo de Proteína do Fotossistema I/metabolismo , Complexo de Proteína do Fotossistema I/genética , Transporte de Elétrons , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Complexo de Proteínas do Centro de Reação Fotossintética/metabolismo , Complexo de Proteínas do Centro de Reação Fotossintética/genética , Cloroplastos/metabolismo , Mutação
3.
Biochem Biophys Res Commun ; 716: 149991, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38704888

RESUMO

Cholera toxin (Ctx) is a major virulence factor produced by Vibrio cholerae that can cause gastrointestinal diseases, including severe watery diarrhea and dehydration, in humans. Ctx binds to target cells through multivalent interactions between its B-subunit pentamer and the receptor ganglioside GM1 present on the cell surface. Here, we identified a series of tetravalent peptides that specifically bind to the receptor-binding region of the B-subunit pentamer using affinity-based screening of multivalent random-peptide libraries. These tetravalent peptides efficiently inhibited not only the cell-elongation phenotype but also the elevated cAMP levels, both of which are induced by Ctx treatment in CHO cells or a human colon carcinoma cell line (Caco-2 cells), respectively. Importantly, one of these peptides, NRR-tet, which was highly efficient in these two activities, markedly inhibited fluid accumulation in the mouse ileum caused by the direct injection of Ctx. In consistent, NRR-tet reduced the extensive Ctx-induced damage of the intestinal villi. After NRR-tet bound to Ctx, the complex was incorporated into the cultured epithelial cells and accumulated in the recycling endosome, affecting the retrograde transport of Ctx from the endosome to the Golgi, which is an essential process for Ctx to exert its toxicity in cells. Thus, NRR-tet may be a novel type of therapeutic agent against cholera, which induces the aberrant transport of Ctx in the intestinal epithelial cells, detoxifying the toxin.


Assuntos
Toxina da Cólera , Cricetulus , Toxina da Cólera/metabolismo , Humanos , Animais , Camundongos , Células CHO , Células CACO-2 , Peptídeos/farmacologia , Peptídeos/metabolismo , Peptídeos/química , Transporte Proteico/efeitos dos fármacos , Cólera/tratamento farmacológico , Cólera/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/efeitos dos fármacos
4.
Plant Physiol ; 192(1): 326-341, 2023 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-36477622

RESUMO

Cyclic electron transport (CET) around Photosystem I (PSI) acidifies the thylakoid lumen and downregulates electron transport at the cytochrome b6f complex. This photosynthetic control is essential for oxidizing special pair chlorophylls (P700) of PSI for PSI photoprotection. In addition, CET depending on the PROTON GRADIENT REGULATION 5 (PGR5) protein oxidizes P700 by moving a pool of electrons from the acceptor side of PSI to the plastoquinone pool. This model of the acceptor-side regulation was proposed on the basis of the phenotype of the Arabidopsis (Arabidopsis thaliana) pgr5-1 mutant expressing Chlamydomonas (Chlamydomonas reinhardtii) plastid terminal oxidase (CrPTOX2). In this study, we extended the research including the Arabidopsis chlororespiratory reduction 2-2 (crr2-2) mutant defective in another CET pathway depending on the chloroplast NADH dehydrogenase-like (NDH) complex. Although the introduction of CrPTOX2 did not complement the defect in the acceptor-side regulation by PGR5, the function of the NDH complex was complemented except for its reverse reaction during the induction of photosynthesis. We evaluated the impact of CrPTOX2 under fluctuating light intensity in the wild-type, pgr5-1 and crr2-2 backgrounds. In the high-light period, both PGR5- and NDH-dependent CET were involved in the induction of photosynthetic control, whereas PGR5-dependent CET preferentially contributed to the acceptor-side regulation. On the contrary, the NDH complex probably contributed to the acceptor-side regulation in the low-light period but not in the high-light period. We evaluated the sensitivity of PSI to fluctuating light and clarified that acceptor-side regulation was necessary for PSI photoprotection by oxidizing P700 under high light.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Complexo de Proteínas do Centro de Reação Fotossintética , Arabidopsis/metabolismo , Transporte de Elétrons , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Oxirredução , Complexo de Proteína do Fotossistema I/genética , Complexo de Proteína do Fotossistema I/metabolismo , Fotossíntese/genética , Luz , Prótons , Complexo de Proteínas do Centro de Reação Fotossintética/genética , Complexo de Proteínas do Centro de Reação Fotossintética/metabolismo
5.
Plant Physiol ; 192(2): 1221-1233, 2023 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-36703219

RESUMO

The chloroplast ATP synthase produces the ATP needed for photosynthesis and plant growth. The trans-membrane flow of protons through the ATP synthase rotates an oligomeric assembly of c subunits, the c-ring. The ion-to-ATP ratio in rotary F1F0-ATP synthases is defined by the number of c-subunits in the rotor c-ring. Engineering the c-ring stoichiometry is, therefore, a possible route to manipulate ATP synthesis by the ATP synthase and hence photosynthetic efficiency in plants. Here, we describe the construction of a tobacco (Nicotiana tabacum) chloroplast atpH (chloroplastic ATP synthase subunit c gene) mutant in which the c-ring stoichiometry was increased from 14 to 15 c-subunits. Although the abundance of the ATP synthase was decreased to 25% of wild-type (WT) levels, the mutant lines grew as well as WT plants and photosynthetic electron transport remained unaffected. To synthesize the necessary ATP for growth, we found that the contribution of the membrane potential to the proton motive force was enhanced to ensure a higher proton flux via the c15-ring without unwanted low pH-induced feedback inhibition of electron transport. Our work opens avenues to manipulate plant ion-to-ATP ratios with potentially beneficial consequences for photosynthesis.


Assuntos
Nicotiana , Fotossíntese , Nicotiana/genética , Nicotiana/metabolismo , Cloroplastos/metabolismo , Transporte de Elétrons , ATPases de Cloroplastos Translocadoras de Prótons/genética , ATPases de Cloroplastos Translocadoras de Prótons/metabolismo , Prótons , Trifosfato de Adenosina/metabolismo
6.
Oncology ; 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38320539

RESUMO

INTRODUCTION: Combination therapy of anti-programmed cell death 1 (PD-1)/programmed cell death ligand 1 (PD-L1) antibodies and platinum-based chemotherapy has been widely used as a first-line treatment for patients with unresectable advanced non-small cell lung cancer (NSCLC) in clinical settings; however, prognostic biomarkers associated with survival outcomes have not been sufficiently investigated. METHODS: We enrolled 147 previously untreated patients with advanced NSCLC who were treated with a combination therapy of anti-PD-1/-PD-L1 antibodies and platinum-based chemotherapy at eight institutions in Nagano Prefecture between December 2018 and April 2023. We evaluated the prognostic value of the geriatric nutritional risk index (GNRI), a systemic inflammatory nutritional biomarker calculated from body weight and serum albumin level, for patients with NSCLC treated with a combination therapy of anti-PD-1/-PD-L1 antibodies and platinum-based chemotherapy. RESULTS: The cutoff value of the GNRI was set at 92. The high GNRI and low GNRI groups included 88 and 59 patients, respectively. The median follow-up period was 15.9 months. The overall survival (OS) in the high GNRI group was significantly longer than that in the low GNRI group (27.9 vs. 15.6 months, p = 0.015). Multivariate analysis revealed that a high GNRI was an independently favorable prognostic predictor for OS (hazard ratio, 1.73; 95% confidence interval, 1.06-2.86; p = 0.031). CONCLUSION: The present study demonstrates that the GNRI is a useful prognostic predictor in patients with NSCLC treated with a combination therapy of anti-PD-1/-PD-L1 antibodies and platinum-based chemotherapy in clinical settings.

7.
Neurol Sci ; 45(7): 3147-3152, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38383749

RESUMO

OBJECTIVE: This study aimed to develop a Japanese version of the New Freezing of Gait Questionnaire (NFOG-Q) and investigate its validity and reliability. METHODS: After translating the NFOG-Q according to a standardised protocol, 56 patients with Parkinson's disease (PD) were administered it. Additionally, the MDS-UPDRS parts II and III, Hoehn and Yahr (H&Y) stage, and number of falls over 1 month were evaluated. Spearman's correlation coefficients (rho) were used to determine construct validity, and Cronbach's alpha (α) was used to examine reliability. RESULTS: The interquartile range of the NFOG-Q scores was 10.0-25.3 (range 0-29). The NFOG-Q scores were strongly correlated with the MDS-UPDRS part II, items 2.12 (walking and balance), 2.13 (freezing), 3.11 (freezing of gait), and 3.12 (postural stability) and the postural instability and gait difficulty score (rho = 0.515-0.669), but only moderately related to the MDS-UPDRS item 3.10 (gait), number of falls, disease duration, H&Y stage, and time of the Timed Up-and-Go test (rho = 0.319-0.434). No significant correlations were observed between age and the time of the 10-m walk test. The internal consistency was excellent (α = 0.96). CONCLUSIONS: The Japanese version of the NFOG-Q is a valid and reliable tool for assessing the severity of freezing in patients with PD.


Assuntos
Transtornos Neurológicos da Marcha , Doença de Parkinson , Humanos , Masculino , Feminino , Idoso , Doença de Parkinson/diagnóstico , Doença de Parkinson/fisiopatologia , Doença de Parkinson/complicações , Transtornos Neurológicos da Marcha/diagnóstico , Transtornos Neurológicos da Marcha/fisiopatologia , Reprodutibilidade dos Testes , Inquéritos e Questionários/normas , Japão , Pessoa de Meia-Idade , Tradução , Índice de Gravidade de Doença , Idoso de 80 Anos ou mais , População do Leste Asiático
8.
J Infect Chemother ; 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38670455

RESUMO

Nocardiosis in patients after allogeneic hematopoietic stem cell transplantation (HSCT) is rare, but is associated with a significant mortality risk. Although trimethoprim-sulfamethoxazole (TMP/SMX) remains the cornerstone of nocardiosis treatment, optimal alternative therapies for patients intolerant to TMP/SMX are not well-established. Herein, we report a case of disseminated nocardiosis with bacteremia and multiple lesions in the lungs and brain caused by Nocardia farcinica, in a 60-year-old man who had previously undergone allogeneic HSCT and was receiving immunosuppressants for severe chronic graft-versus-host disease. The patient received atovaquone for the prophylaxis of Pneumocystis pneumonia because of a previous serious allergic reaction to TMP/SMX. The patient was initially treated with imipenem/cilastatin and amikacin, which were later switched to ceftriaxone and amikacin based on the results of antimicrobial susceptibility testing. After switching to oral levofloxacin and a standard dose of minocycline, the patient experienced a single recurrence of brain abscesses. However, after switching to oral moxifloxacin and high-dose minocycline, the patient did not experience any relapses during the subsequent two years and seven months of treatment. In treating nocardiosis with brain abscesses, it is crucial to select oral antibiotics based on the antimicrobial susceptibility test results and pharmacokinetics, especially when TMP/SMX is contraindicated. A combination of oral moxifloxacin and high-dose minocycline could be a promising alternative therapy.

9.
Clin Immunol ; 250: 109317, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37015317

RESUMO

The receptor for advanced glycation end-products (RAGE) is a pattern recognition receptor that regulates inflammation, cell migration, and cell fate. Systemic lupus erythematosus (SLE) is a chronic multiorgan autoimmune disease. To understand the function of RAGE in SLE, we generated RAGE-deficient (Ager-/-) lupus-prone mice by backcrossing MRL/MpJ-Faslpr/J (MRL-lpr) mice with Ager-/- C57BL/6 mice. In 18-week-old Ager-/- MRL-lpr, the weights of the spleen and lymph nodes, as well as the frequency of CD3+CD4-CD8- cells, were significantly decreased. Ager-/- MRL-lpr mice had significantly reduced urine albumin/creatinine ratios and markedly improved renal pathological scores. Moreover, neutrophil infiltration and neutrophil extracellular trap formation in the glomerulus were significantly reduced in Ager-/- MRL-lpr. Our study is the first to reveal that RAGE can have a pathologic role in immune cells, particularly neutrophils and T cells, in inflammatory tissues and suggests that the inhibition of RAGE may be a potential therapeutic strategy for SLE.


Assuntos
Armadilhas Extracelulares , Lúpus Eritematoso Sistêmico , Nefrite Lúpica , Camundongos , Animais , Receptor para Produtos Finais de Glicação Avançada/genética , Reação de Maillard , Camundongos Endogâmicos MRL lpr , Camundongos Endogâmicos C57BL
10.
Small ; 19(32): e2302714, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37154235

RESUMO

Chiral molecules have recently received renewed interest as highly efficient sources of spin-selective charge emission known as chiral-induced spin selectivity (CISS), which potentially offers a fascinating utilization of organic chiral materials in novel solid-state spintronic devices. However, a practical use of CISS remains far from completion, and rather fundamental obstacles such as (i) external controllability of spin, (ii) function durability, and (iii) improvement of spin-polarization efficiency have not been surmounted to date. In this study, these issues are addressed by developing a self-assembled monolayer (SAM) of overcrowded alkene (OCA)-based molecular motor. With this system, it is successfully demonstrated that the direction of spin polarization can be externally and repeatedly manipulated in an extremely stable manner by switching the molecular chirality, which is achieved by a formation of the covalent bonds between the molecules and electrode. In addition, it is found that a higher stereo-ordering architecture of the SAM of OCAs tailored by mixing them with simple alkanethiols considerably enhances the efficiency of spin polarization per a single OCA molecule. All these findings provide the creditable feasibility study for strongly boosting development of CISS-based spintronic devices that can simultaneously fulfill the controllability, durability, and high spin-polarization efficiency.

11.
Plant Physiol ; 188(2): 1264-1276, 2022 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-34792607

RESUMO

Plastid terminal oxidase (PTOX) accepts electrons from plastoquinol to reduce molecular oxygen to water. We introduced the gene encoding Chlamydomonas reinhardtii (Cr)PTOX2 into the Arabidopsis (Arabidopsis thaliana) wild-type (WT) and proton gradient regulation5 (pgr5) mutant defective in cyclic electron transport around photosystem I (PSI). The accumulation of CrPTOX2 only mildly affected photosynthetic electron transport in the WT background during steady-state photosynthesis but partly complemented the induction of nonphotochemical quenching (NPQ) in the pgr5 background. During the induction of photosynthesis by actinic light (AL) of 130 µmol photons m-2 s-1, the high level of PSII yield (Y(II)) was induced immediately after the onset of AL in WT plants accumulating CrPTOX2. NPQ was more rapidly induced in the transgenic plants than in WT plants. P700 was also oxidized immediately after the onset of AL. Although CrPTOX2 does not directly induce a proton concentration gradient (ΔpH) across the thylakoid membrane, the coupled reaction of PSII generated ΔpH to induce NPQ and the downregulation of the cytochrome b6f complex. Rapid induction of Y(II) and NPQ was also observed in the pgr5 plants accumulating CrPTOX2. In contrast to the WT background, P700 was not oxidized in the pgr5 background. Although the thylakoid lumen was acidified by CrPTOX2, PGR5 was essential for oxidizing P700. In addition to acidification of the thylakoid lumen to downregulate the cytochrome b6f complex (donor-side regulation), PGR5 may be required for draining electrons from PSI by transferring them to the plastoquinone pool. We propose a reevaluation of the contribution of this acceptor-side regulation by PGR5 in the photoprotection of PSI.


Assuntos
Arabidopsis/genética , Arabidopsis/metabolismo , Clorofila/metabolismo , Transporte de Elétrons/genética , Oxirredutases/metabolismo , Fotossíntese/genética , Fotossíntese/fisiologia , Chlamydomonas reinhardtii/genética , Clorofila/genética , Variação Genética , Genótipo , Mutação , Oxirredução , Oxirredutases/genética , Plantas Geneticamente Modificadas/metabolismo
12.
J Vasc Surg ; 77(6): 1751-1759, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36796593

RESUMO

OBJECTIVE: To compare the results of endovascular treatment with drug-eluting stents (DES) and drug-coated balloons (DCB) in atherosclerotic lesions in the femoropopliteal artery, as well as to assess restenotic patterns. METHODS: Clinical data from 617 cases treated with DES or DCB for femoropopliteal diseases were analyzed in this multicenter, retrospective cohort study. From these, 290 DES and 145 DCB cases were extracted by propensity score matching. Outcomes investigated were 1- and 2-year primary patency, reintervention, and restenotic pattern and its impact on symptoms in each group. RESULTS: The primary patency rates at 1 and 2 years in the DES group were superior to those in the DCB group (84.8% and 71.1% vs 81.3% and 66.6%, P = .043), whereas there was no significant difference in freedom from target lesion revascularization (91.6% and 82.6% vs 88.3% and 78.8%, P = .13). Compared with what was measured before the index procedures, exacerbated symptoms, rate of occlusion, and an increase in the occluded length at loss of patency were more frequent in the DES group than in the DCB group. The odds ratios were 3.53 (95% confidence interval, 1.31-9.49; P = .012), 3.61 (1.09-11.9; P = .036), and 3.82 (1.15-12.7; P = .029), respectively. On the other hand, the frequency of an increase in lesion length and requirement of target lesion revascularization were similar between the two groups. CONCLUSIONS: Primary patency was significantly higher at 1 and 2 years in the DES than in the DCB group. However, DES were associated with exacerbated clinical symptoms and complicated lesion characteristics at the point of loss of patency.


Assuntos
Angioplastia com Balão , Stents Farmacológicos , Doença Arterial Periférica , Humanos , Artéria Poplítea/diagnóstico por imagem , Artéria Poplítea/cirurgia , Estudos Retrospectivos , Resultado do Tratamento , Grau de Desobstrução Vascular , Angioplastia com Balão/efeitos adversos , Artéria Femoral/diagnóstico por imagem , Artéria Femoral/cirurgia , Materiais Revestidos Biocompatíveis , Doença Arterial Periférica/diagnóstico por imagem , Doença Arterial Periférica/terapia
13.
Chemistry ; 29(43): e202300940, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37194414

RESUMO

The selective synthesis of nickel and copper complexes of 19-benzoyl-5,10,15-triphenyl-bilatrien-1-one (H2 TPBT) is reported, a molecule which crystallizes as a molecular helix of one-and-a-quarter which turns with a 5.7 Šradius and a 3.2 Špitch, and all 26 participating atoms are sp2 -hybridized. UV/vis, ECD, ESR and cyclic voltammetry experiments reveal a strong interaction between metal and ligand and partial radical character when copper is coordinated instead of nickel. Strong ECD absorption in the 800 nm range is found which, using TD-DFT calculations as well as literature spectra, is shown to be highly tunable both by metal coordination and variation of the aryl groups in the TPBT periphery. The radical character of the ligand in Cu(TPBT) enables rapid interconversion between (M)- and (P)-enantiomers, possibly via intermittent breakage of a Cu-N bond. The 19-benzoyl group kinetically stabilizes enantiopure (M/P)-Ni(TPBT). The results are interpreted with regard to the application as circularly polarized light (CPL) detectors as well as to the chirality-induced spin-selectivity (CISS) effect which is currently lacking a concise theoretical model.

14.
Environ Sci Technol ; 57(34): 12654-12662, 2023 08 29.
Artigo em Inglês | MEDLINE | ID: mdl-37585234

RESUMO

Although environmental RNA (eRNA) is emerging as a noninvasive tool to assess the health status of aquatic macroorganisms, the potential of eRNA in assessing chemical hazards remain largely untested. In this study, we investigated the ability of eRNA to detect changes in gene expression in Japanese medaka fish (Oryzias latipes) in response to sublethal pyrene exposure, as a model toxic chemical. We performed standardized acute toxicity tests and collected eRNA from tank water and RNA from fish tissue after 96 h of exposure. Our results showed that over 1000 genes were detected in eRNA and the sequenced read counts of these genes correlated with those in fish tissue (r = 0.50). Moreover, eRNA detected 86 differentially expressed genes in response to pyrene, some of which were shared by fish RNA, including the suppression of collagen fiber genes. These results suggest that eRNA has the potential to detect changes in gene expression in fish in response to environmental stressors without the need for sacrificing or causing pain to fish. However, we also found that the majority of sequenced reads of eRNA (>99%) were not mapped to the reference medaka genome and they originated from bacteria and fungi, resulting in low sequencing depth. In addition, eRNA, in particular nuclear genes, was highly degraded with a median transcript integrity number (TIN) of <20. These limitations highlight the need for future studies to improve the analytical methods of eRNA application.


Assuntos
Oryzias , Poluentes Químicos da Água , Animais , RNA , Oryzias/genética , Pirenos , Poluentes Químicos da Água/toxicidade
15.
Biol Pharm Bull ; 46(7): 969-978, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37394647

RESUMO

11ß-Hydroxysteroid dehydrogenase type 1 (11ß-HSD1) is the only enzyme that converts inactive glucocorticoids to active forms and plays an important role in the regulation of glucocorticoid action in target tissues. JTT-654 is a selective 11ß-HSD1 inhibitor and we investigated its pharmacological properties in cortisone-treated rats and non-obese type 2 diabetic Goto-Kakizaki (GK) rats because Asians, including Japanese, are more likely to have non-obese type 2 diabetics. Systemic cortisone treatment increased fasting plasma glucose and insulin levels and impaired insulin action on glucose disposal rate and hepatic glucose production assessed by hyperinsulinemic-euglycemic clamp, but all these effects were attenuated by JTT-654 administration. Cortisone treatment also reduced basal and insulin-stimulated glucose oxidation in adipose tissue, increased plasma glucose levels after administration of the pyruvate, the substrate of gluconeogenesis, and increased liver glycogen content. Administration of JTT-654 also inhibited all of these effects. Cortisone treatment decreased basal and insulin-stimulated 2-deoxy-D-[1-3H]-glucose uptake in 3T3-L1 adipocytes and increased the release of free fatty acids and glycerol, a gluconeogenic substrate, from 3T3-L1 adipocytes, and JTT-654 significantly attenuated these effects. In GK rats, JTT-654 treatment significantly reduced fasting plasma glucose and insulin levels, enhanced insulin-stimulated glucose oxidation in adipose tissue, and suppressed hepatic gluconeogenesis as assessed by pyruvate administration. These results demonstrated that glucocorticoid was involved in the pathology of diabetes in GK rats, as in cortisone-treated rats, and that JTT-654 ameliorated the diabetic conditions. Our results suggest that JTT-654 ameliorates insulin resistance and non-obese type 2 diabetes by inhibiting adipose tissue and liver 11ß-HSD1.


Assuntos
Cortisona , Diabetes Mellitus Tipo 2 , Resistência à Insulina , Ratos , Animais , Glucocorticoides/uso terapêutico , 11-beta-Hidroxiesteroide Desidrogenase Tipo 1 , Cortisona/uso terapêutico , Cortisona/farmacologia , Glicemia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Obesidade/patologia , Insulina , Glucose
16.
Risk Anal ; 43(4): 686-699, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-35599017

RESUMO

The quality of chemical management depends more or less on practical procedures used to assess chemicals. This study quantitatively assessed the efficacy of a derivation procedure for calculating no-effect concentrations for screening assessment of environmental hazards under the Chemical Substance Control Law in Japan. We first evaluated the derivation procedure by applying a series of test ecotoxicity datasets to the procedure and calculating the resulting misclassification rates of the hazardous class of chemicals. In this study, a chemical was deemed to have been misclassified if its classification differed from its classification based on the full dataset (chronic toxicity data for three trophic levels), which was defined as the correct assignment. We also calculated the effects of additional uncertainty factors to decrease the variance (i.e., to improve the consistency) of the misclassification rates among cases with different data availability in the derivation procedure. The results showed that the derivation procedure resulted in very high rates of misclassification when only particular sets of ecotoxicity data were available (e.g., only chronic toxicity data of algae were available). Our analyses also showed that the use of additional uncertainty factors improved the consistency of the misclassification rates within the derivation procedure. Our study presents a broadly applicable calculation framework for quantifying error rates in assessment procedures and serves as a case study for future development and reforms of chemical assessment processes and policies, while additional analyses using more extensive ecotoxicity data with various modes of actions are needed in the future.


Assuntos
Poluentes Químicos da Água , Poluentes Químicos da Água/análise , Japão , Medição de Risco/métodos
17.
Ecotoxicology ; 32(6): 824-836, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37592026

RESUMO

Macroalgae are one of the main producers in marine environments. However, only a few toxicity test methods have been established that use reference strains of macroalgae to evaluate the effects of chemicals on the growth and reproduction of macroalgae to monitor water quality. We selected reference strains of Chlorophyta, Ulva aragoënsis; Phaeophyceae, Ectocarpus siliculosus; and wakame, Undaria pinnatifida, as test species to establish a microplate-based method to investigate the toxicity of potassium dichromate, 3,5-dichlorophenol, and two common herbicides (diuron and simazine). We determined the growth of the three macroalgae in their early life stages and during the sporangia formation stage in E. siliculosus under laboratory conditions. We observed that the growth and sporangia formation in these algae were impaired in a dose-dependent manner. Additionally, we investigated the sensitivity of these macroalgae by comparing the toxicity values of toxicants used in this study with those obtained from a database. Compared to other microalgae and plant species, macroalgae showed a relatively high sensitivity to organic compounds, including herbicides. Growth tests using U. aragoënsis and E. siliculosus produced reliable results at 0-32 and 25-32 practical salinity units (PSU), respectively. The tests established in this study could test the toxicity of chemical substances in macroalgae and are thus expected to contribute to a better understanding of the environmental risks of chemical substances on aquatic biota. The tests could be applied to all effluent toxicity tests used for the management of seawater and brackish water quality.


Assuntos
Clorófitas , Herbicidas , Phaeophyceae , Alga Marinha , Undaria , Herbicidas/toxicidade , Bioensaio
18.
Int J Mol Sci ; 24(13)2023 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-37445678

RESUMO

Atrial fibrillation (AF) is the most frequent persistent arrhythmia. Many genes have been reported as a genetic background for AF. However, most transcriptome analyses of AF are limited to the atrial samples and have not been evaluated by multiple cardiac regions. In this study, we analyzed the expression levels of protein-coding and long noncoding RNAs (lncRNAs) in six cardiac regions by RNA-seq. Samples were donated from six subjects with or without persistent AF for left atria, left atrial appendages, right atria, sinoatrial nodes, left ventricles, right ventricles, and pulmonary veins (PVs), and additional four right atrial appendages samples were collected from patients undergoing mitral valve replacement. In total, 23 AF samples were compared to 23 non-AF samples. Surprisingly, the most influenced heart region in gene expression by AF was the PV, not the atria. The ion channel-related gene set was significantly enriched upon analysis of these significant genes. In addition, some significant genes are cancer-related lncRNAs in PV in AF. A co-expression network analysis could detect the functional gene clusters. In particular, the cancer-related lncRNA, such as SAMMSON and FOXCUT, belong to the gene network with the cancer-related transcription factor FOXC1. Thus, they may also play an aggravating role in the pathogenesis of AF, similar to carcinogenesis. In the least, this study suggests that (1) RNA alteration is most intense in PVs and (2) post-transcriptional gene regulation by lncRNA may contribute to the progression of AF. Through the screening analysis across the six cardiac regions, the possibility that the PV region can play a role other than paroxysmal triggering in the pathogenesis of AF was demonstrated for the first time. Future research with an increase in the number of PV samples will lead to a novel understanding of the pathophysiology of AF.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Neoplasias , Veias Pulmonares , RNA Longo não Codificante , Humanos , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Veias Pulmonares/metabolismo , Átrios do Coração/patologia , Biologia Computacional , Neoplasias/metabolismo
19.
Plant J ; 107(3): 876-892, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34028907

RESUMO

High-light (HL) stress enhances the production of H2 O2 from the photosynthetic electron transport chain in chloroplasts, potentially causing photo-oxidative damage. Although stromal and thylakoid membrane-bound ascorbate peroxidases (sAPX and tAPX, respectively) are major H2 O2 -scavenging enzymes in chloroplasts, their knockout mutants do not exhibit a visible phenotype under HL stress. Trans-thylakoid proton gradient (∆pH)-dependent mechanisms exist for controlling H2 O2 production from photosynthesis, such as thermal dissipation of light energy and downregulation of electron transfer between photosystems II and I, and these may compensate for the lack of APXs. To test this hypothesis, we focused on a proton gradient regulation 5 (pgr5) mutant, wherein both ∆pH-dependent mechanisms are impaired, and an Arabidopsis sapx tapx double mutant was crossed with the pgr5 single mutant. The sapx tapx pgr5 triple mutant exhibited extreme sensitivity to HL compared with its parental lines. This phenotype was consistent with cellular redox perturbations and enhanced expression of many oxidative stress-responsive genes. These findings demonstrate that the PGR5-dependent mechanisms compensate for chloroplast APXs, and vice versa. An intriguing finding was that the failure of induction of non-photochemical quenching in pgr5 (because of the limitation in ∆pH formation) was partially recovered in sapx tapx pgr5. Further genetic studies suggested that this recovery was dependent on the NADH dehydrogenase-like complex-dependent pathway for cyclic electron flow around photosystem I. Together with data from the sapx tapx npq4 mutant, we discuss the interrelationship between APXs and ∆pH-dependent mechanisms under HL stress.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Ascorbato Peroxidases/metabolismo , Proteínas de Cloroplastos/metabolismo , Cloroplastos/enzimologia , Complexos de Proteínas Captadores de Luz/metabolismo , Complexo de Proteínas do Centro de Reação Fotossintética/metabolismo , Complexo de Proteína do Fotossistema II/metabolismo , Proteínas das Membranas dos Tilacoides/metabolismo , Antioxidantes , Arabidopsis/efeitos dos fármacos , Proteínas de Arabidopsis/genética , Ascorbato Peroxidases/genética , Proteínas de Cloroplastos/genética , Regulação Enzimológica da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Concentração de Íons de Hidrogênio , Complexos de Proteínas Captadores de Luz/genética , Mutação , Oxirredução , Fotossíntese , Complexo de Proteínas do Centro de Reação Fotossintética/genética , Complexo de Proteína do Fotossistema II/genética , Estresse Fisiológico/efeitos da radiação , Proteínas das Membranas dos Tilacoides/genética
20.
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
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