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1.
Gan To Kagaku Ryoho ; 51(7): 735-739, 2024 Jul.
Artigo em Japonês | MEDLINE | ID: mdl-39191691

RESUMO

In cancer patients, pain control is reportedly affected by the quality of their nutritional status as the disease progresses. We conducted a study of patients who were continuously using oral opioid analgesics for the treatment of cancer pain at Chibaken Saiseikai Narashino Hospital from September 2020 to August 2022. Patient characteristics and pain treatments were compared between the well-nourished group(mGPS 0 or 1, n=20)and poorly nourished group(mGPS 2, n=47). Univariate analysis revealed significant differences between the 2 groups in terms of sex and the presence or absence of concomitant analgesic adjuvant(p<0.05). According to the multivariate analysis, the presence or absence of concomitant analgesic adjuvant was a significant related factor, with an odds ratio of 11.409(95% confidence interval: 2.645-49.217, p=0.001). For patients in the poorly nourished group who were able to maintain a general condition that allowed for oral administration, treatment was continued without affecting pain control. In the well-nourished group, most patients used gabapentinoids as an analgesic adjuvant, whereas in the poorly nourished group, avoidable side effects, such as dizziness and lightheadedness, might affect the patient's quality of life.


Assuntos
Analgésicos Opioides , Dor do Câncer , Estado Nutricional , Humanos , Masculino , Feminino , Analgésicos Opioides/uso terapêutico , Analgésicos Opioides/administração & dosagem , Administração Oral , Dor do Câncer/tratamento farmacológico , Idoso , Pessoa de Meia-Idade , Adulto , Idoso de 80 Anos ou mais , Manejo da Dor/métodos , Neoplasias/complicações , Neoplasias/tratamento farmacológico
2.
Front Vet Sci ; 11: 1345548, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38881783

RESUMO

In older horses, basal metabolic rate decreases, and plasma metabolite and hormone concentrations related to energy metabolism change. The occurrence of age-related diseases, which increases in old animals, may enhance inflammatory reactivity (inflammaging). Finding the appropriate treatment for inflammaging at an early stage may prevent various age-related diseases. Changes in metabolite and hormone concentrations and enzyme activities involved in energy metabolism in the plasma of clinically healthy riding horses of various ages were measured to identify biomarkers of inflammaging (persistent low-grade inflammation that occurs with aging). All horses were clinically healthy, and their body condition scores (BCSs) were 4 or 5 (9-point scale). Plasma triglyceride (TG), total cholesterol (T-Cho), blood urea nitrogen (BUN), insulin concentrations, malondialdehyde (MDA), and serum amyloid A (SAA) concentrations generally increased with age. Adiponectin concentrations, plasma superoxide dismutase (SOD), and leukocyte AMP-activated protein kinase (AMPK) activities decreased, while plasma aspartate aminotransferase (AST), alanine aminotransferase (ALT), and glutathione peroxidase (GPx) remained unchanged as horses aged. Although riding horses that partake in continuous exercise seems to be less likely to develop inflammaging, horses over 17 years of age tend to show proinflammatory signs with disordered lipid metabolism. In riding horses, SAA, in combination with other markers, may be a useful biomarker for inflammaging and dysregulated lipid metabolism in aging horses.

3.
Protein Sci ; 33(6): e5017, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38747382

RESUMO

Biparatopic antibodies (bpAbs) are engineered antibodies that bind to multiple different epitopes within the same antigens. bpAbs comprise diverse formats, including fragment-based formats, and choosing the appropriate molecular format for a desired function against a target molecule is a challenging task. Moreover, optimizing the design of constructs requires selecting appropriate antibody modalities and adjusting linker length for individual bpAbs. Therefore, it is crucial to understand the characteristics of bpAbs at the molecular level. In this study, we first obtained single-chain variable fragments and camelid heavy-chain variable domains targeting distinct epitopes of the metal binding protein MtsA and then developed a novel format single-chain bpAb connecting these fragment antibodies with various linkers. The physicochemical properties, binding activities, complex formation states with antigen, and functions of the bpAb were analyzed using multiple approaches. Notably, we found that the assembly state of the complexes was controlled by a linker and that longer linkers tended to form more compact complexes. These observations provide detailed molecular information that should be considered in the design of bpAbs.


Assuntos
Anticorpos de Cadeia Única , Anticorpos de Cadeia Única/química , Anticorpos de Cadeia Única/genética , Anticorpos de Cadeia Única/imunologia , Animais , Humanos , Engenharia de Proteínas/métodos , Epitopos/química , Epitopos/imunologia , Cadeias Pesadas de Imunoglobulinas/química , Cadeias Pesadas de Imunoglobulinas/genética , Cadeias Pesadas de Imunoglobulinas/imunologia
4.
Biochim Biophys Acta Biomembr ; 1866(5): 184323, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38614236

RESUMO

Protamine, an antimicrobial protein derived from salmon sperm with a molecular weight of approximately 5 kDa, is composed of 60-70 % arginine and is a highly charged protein. Here, we investigated the mechanism of antimicrobial action of protamine against Cutibacterium acnes (C. acnes) focusing on its rich arginine content and strong positive charge. Especially, we focused on the attribution of dual mechanisms of antimicrobial protein, including membrane disruption or interaction with intracellular components. We first determined the dose-dependent antibacterial activity of protamine against C. acnes. In order to explore the interaction between bacterial membrane and protamine, we analyzed cell morphology, zeta potential, membrane permeability, and the composition of membrane fatty acid. In addition, the localization of protamine in bacteria was observed using fluorescent-labeled protamine. For investigation of the intracellular targets of protamine, bacterial translation was examined using a cell-free translation system. Based on our results, the mechanism of the antimicrobial action of protamine against C. acnes is as follows: 1) electrostatic interactions with the bacterial cell membrane; 2) self-internalization into the bacterial cell by changing the composition of the bacterial membrane; and 3) inhibition of bacterial growth by blocking translation inside the bacteria. However, owing to its strong electric charge, protamine can also interact with DNA, RNA, and other proteins inside the bacteria, and may inhibit various bacterial life processes beyond the translation process.


Assuntos
Arginina , Membrana Celular , Protaminas , Protaminas/química , Protaminas/farmacologia , Protaminas/metabolismo , Arginina/química , Arginina/farmacologia , Arginina/metabolismo , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Animais , Antibacterianos/farmacologia , Antibacterianos/química , Eletricidade Estática , Permeabilidade da Membrana Celular/efeitos dos fármacos , Testes de Sensibilidade Microbiana
5.
Arch Biochem Biophys ; 753: 109926, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38346547

RESUMO

Of the more than 100 families of glycosyltransferases, family 1 glycosyltransferases catalyze glycosylation using uridine diphosphate (UDP)-sugar as a sugar donor and are thus referred to as UDP-sugar:glycosyl transferases. The blue color of the Nemophila menziesii flower is derived from metalloanthocyanin, which consists of anthocyanin, flavone, and metal ions. Flavone 7-O-ß-glucoside-4'-O-ß-glucoside in the plant is sequentially biosynthesized from flavons by UDP-glucose:flavone 4'-O-glucosyltransferase (NmF4'GT) and UDP-glucose:flavone 4'-O-glucoside 7-O-glucosyltransferase (NmF4'G7GT). To identify the molecular mechanisms of glucosylation of flavone, the crystal structures of NmF4'G7GT in its apo form and in complex with UDP-glucose or luteolin were determined, and molecular structure prediction using AlphaFold2 was conducted for NmF4'GT. The crystal structures revealed that the size of the ligand-binding pocket and interaction environment for the glucose moiety at the pocket entrance plays a critical role in the substrate preference in NmF4'G7GT. The substrate specificity of NmF4'GT was examined by comparing its model structure with that of NmF4'G7GT. The structure of NmF4'GT may have a smaller acceptor pocket, leading to a substrate preference for non-glucosylated flavones (or flavone aglycones).


Assuntos
Flavonas , Glucosiltransferases , Glucosiltransferases/química , Glucosiltransferases/metabolismo , Ligantes , Uridina Difosfato Glucose/química , Glucose , Glicosiltransferases , Glucosídeos , Especificidade por Substrato
6.
J Biochem ; 175(6): 587-598, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38227611

RESUMO

The rapid emergence of multi-drug-resistant bacteria has raised a serious public health concern. Therefore, new antibiotic developments have been highly desired. Here, we propose a new method to visualize antibiotic actions on translating ribosomes in the cell-free system under macromolecular crowding conditions by cryo-electron microscopy, designated as the DARC method: the Direct visualization of Antibiotic binding on Ribosomes in the Cell-free translation system. This new method allows for acquiring a more comprehensive understanding of the mode of action of antibiotics on the translation inhibition without ribosome purification. Furthermore, with the direct link to biochemical analysis at the same condition as cryo-EM observation, we revealed the evolution of 2-DOS aminoglycosides from dibekacin (DBK) to arbekacin (ABK) by acquiring the synthetic tailored anchoring motif to lead to stronger binding affinity to ribosomes. Our cryo-EM structures of DBK and ABK bound ribosomes in the cell-free environment clearly depicted a synthetic tailored γ-amino-α-hydroxybutyryl (HABA) motif formed additional interactions with the ribosome enhancing antibiotic bindings. This new approach would be valuable for understanding the function of antibiotics for more efficient drug development.


Assuntos
Aminoglicosídeos , Antibacterianos , Sistema Livre de Células , Microscopia Crioeletrônica , Ribossomos , Ribossomos/metabolismo , Sistema Livre de Células/metabolismo , Aminoglicosídeos/farmacologia , Aminoglicosídeos/metabolismo , Aminoglicosídeos/química , Microscopia Crioeletrônica/métodos , Antibacterianos/farmacologia , Biossíntese de Proteínas/efeitos dos fármacos
7.
J Biol Chem ; 299(12): 105393, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37890784

RESUMO

Membrane transport proteins require a gating mechanism that opens and closes the substrate transport pathway to carry out unidirectional transport. The "gating" involves large conformational changes and is achieved via multistep reactions. However, these elementary steps have not been clarified for most transporters due to the difficulty of detecting the individual steps. Here, we propose these steps for the gate opening of the bacterial Na+ pump rhodopsin, which outwardly pumps Na+ upon illumination. We herein solved an asymmetric dimer structure of Na+ pump rhodopsin from the bacterium Indibacter alkaliphilus. In one protomer, the Arg108 sidechain is oriented toward the protein center and appears to block a Na+ release pathway to the extracellular (EC) medium. In the other protomer, however, this sidechain swings to the EC side and then opens the release pathway. Assuming that the latter protomer mimics the Na+-releasing intermediate, we examined the mechanism for the swing motion of the Arg108 sidechain. On the EC surface of the first protomer, there is a characteristic cluster consisting of Glu10, Glu159, and Arg242 residues connecting three helices. In contrast, this cluster is disrupted in the second protomer. Our experimental results suggested that this disruption is a key process. The cluster disruption induces the outward movement of the Glu159-Arg242 pair and simultaneously rotates the seventh transmembrane helix. This rotation resultantly opens a space for the swing motion of the Arg108 sidechain. Thus, cluster disruption might occur during the photoreaction and then trigger sequential conformation changes leading to the gate-open state.


Assuntos
Rodopsina , Membrana Celular/metabolismo , Transporte de Íons , Íons/metabolismo , Subunidades Proteicas/metabolismo , Rodopsina/química , Rodopsina/metabolismo , ATPase Trocadora de Sódio-Potássio/metabolismo , Animais
8.
RSC Chem Biol ; 4(8): 564-572, 2023 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-37547453

RESUMO

Pancreatic cancer is highly metastatic and has poor prognosis, mainly due to delayed detection, often after metastasis has occurred. A novel method to enable early detection and disease intervention is strongly needed. Here we unveil for the first time that pancreatic cancer cells (PANC-1) and secreted exosomes express MUC1 bearing cancer-relevant dynamic epitopes recognized specifically by an anti-MUC1 antibody (SN-131), which binds specifically core 1 but not core 2 type O-glycans found in normal cells. Comprehensive assessment of the essential epitope for SN-131 indicates that PANC-1 cells produce dominantly MUC1 with aberrant O-glycoforms such as Tn, T, and sialyl T (ST) antigens. Importantly, SN-131 showed the highest affinity with MUC1 bearing ST antigen at the immunodominant DTR motif (KD = 1.58 nM) independent of the glycosylation states of other Ser/Thr residues in the MUC1 tandem repeats. The X-ray structure revealed that SN-131 interacts directly with Neu5Ac and root GalNAc of the ST antigen in addition to the proximal peptide region. Our results demonstrate that targeting O-glycosylated "dynamic neoepitopes" found in the membrane-tethered MUC1 is a promising therapeutic strategy for improving the treatment outcome of patients with pancreatic cancer.

9.
Biotechnol J ; 18(11): e2300039, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37458140

RESUMO

Phage display and biopanning are powerful tools for generating binding molecules for a specific target. However, the selection process based only on binding affinity provides no assurance for the antibody's affinity to the target epitope. In this study, we propose a molecular-evolution approach guided by native protein-protein interactions to generate epitope-targeting antibodies. The binding-site sequence in a native protein was grafted into a complementarity-determining region (CDR) in the nanobody, and a nonrelated CDR loop (in the grafted nanobody) was randomized to create a phage display library. In this construction of nanobodies by integrating graft and evolution technology (CAnIGET method), suitable grafting of the functional sequence added functionality to the nanobody, and the molecular-evolution approach enhanced the binding function to inhibit the native protein-protein interactions. To apply for biological tool with growth screening, model nanobodies with an affinity for filamenting temperature-sensitive mutant Z (FtsZ) from Staphylococcus aureus were constructed and completely inhibited the polymerization of FtsZ as a function. Consequently, the expression of these nanobodies drastically decreased the cell division rate. We demonstrate the potential of the CAnIGET method with the use of native protein-protein interactions for steady epitope-specific evolutionary engineering.


Assuntos
Biblioteca de Peptídeos , Anticorpos de Domínio Único , Anticorpos , Técnicas de Visualização da Superfície Celular , Regiões Determinantes de Complementaridade , Epitopos , Anticorpos de Domínio Único/genética , Anticorpos de Domínio Único/química
10.
ACS Synth Biol ; 12(5): 1437-1446, 2023 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-37155350

RESUMO

Artificial cells are membrane vesicles mimicking cellular functions. To date, giant unilamellar vesicles made from a single lipid membrane with a diameter of 10 µm or more have been used to create artificial cells. However, the creation of artificial cells that mimic the membrane structure and size of bacteria has been limited due to technical restrictions of conventional liposome preparation methods. Here, we created bacteria-sized large unilamellar vesicles (LUVs) with proteins localized asymmetrically to the lipid bilayer. Liposomes containing benzylguanine-modified phospholipids were prepared by combining the conventional water-in-oil emulsion method and the extruder method, and green fluorescent protein fused with SNAP-tag was localized to the inner leaflet of the lipid bilayer. Biotinylated lipid molecules were then inserted externally, and the outer leaflet was modified with streptavidin. The resulting liposomes had a size distribution in the range of 500-2000 nm with a peak at 841 nm (the coefficient of variation was 10.3%), which was similar to that of spherical bacterial cells. Fluorescence microscopy, quantitative evaluation using flow cytometry, and western blotting proved the intended localization of different proteins on the lipid membrane. Cryogenic electron microscopy and quantitative evaluation by α-hemolysin insertion revealed that most of the created liposomes were unilamellar. Our simple method for the preparation of bacteria-sized LUVs with asymmetrically localized proteins will contribute to the creation of artificial bacterial cells for investigating functions and the significance of their surface structure and size.


Assuntos
Lipossomos , Lipossomas Unilamelares , Lipossomos/química , Lipossomas Unilamelares/química , Bicamadas Lipídicas/química , Fosfolipídeos , Microscopia de Fluorescência , Bactérias
11.
Sci Rep ; 13(1): 7392, 2023 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-37149706

RESUMO

Vitamin E is classified into tocopherol (Toc) and tocotrienol (T3) based on its side chains. T3 generally has higher cellular uptake than Toc, though the responsible mechanism remains unclear. To elucidate this mechanism, we hypothesized and investigated whether serum albumin is a factor that induces such a difference in the cellular uptake of Toc and T3. Adding bovine serum albumin (BSA) to serum-depleted media increased the cellular uptake of T3 and decreased that of Toc, with varying degrees among α-, ß-, γ-, and δ-analogs. Such enhanced uptake of α-T3 was not observed when cells were incubated under low temperature (the uptake of α-Toc was also reduced), suggesting that Toc and T3 bind to albumin to form a complex that results in differential cellular uptake of vitamin E. Fluorescence quenching study confirmed that vitamin E certainly bound to BSA, and that T3 showed a higher affinity than Toc. Molecular docking further indicated that the differential binding energy of Toc or T3 to BSA is due to the Van der Waals interactions via their side chain. Overall, these results suggested that the affinity of Toc and T3 to albumin differs due to their side chains, causing the difference in their albumin-mediated cellular uptake. Our results give a better mechanistic insight into the physiological action of vitamin E.


Assuntos
Tocoferóis , Tocotrienóis , Tocoferóis/farmacologia , Simulação de Acoplamento Molecular , Vitamina E/metabolismo , Albuminas , Soroalbumina Bovina
12.
Nat Commun ; 14(1): 2131, 2023 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-37080962

RESUMO

Although several ribosomal protein paralogs are expressed in a tissue-specific manner, how these proteins affect translation and why they are required only in certain tissues have remained unclear. Here we show that RPL3L, a paralog of RPL3 specifically expressed in heart and skeletal muscle, influences translation elongation dynamics. Deficiency of RPL3L-containing ribosomes in RPL3L knockout male mice resulted in impaired cardiac contractility. Ribosome occupancy at mRNA codons was found to be altered in the RPL3L-deficient heart, and the changes were negatively correlated with those observed in myoblasts overexpressing RPL3L. RPL3L-containing ribosomes were less prone to collisions compared with RPL3-containing canonical ribosomes. Although the loss of RPL3L-containing ribosomes altered translation elongation dynamics for the entire transcriptome, its effects were most pronounced for transcripts related to cardiac muscle contraction and dilated cardiomyopathy, with the abundance of the encoded proteins being correspondingly decreased. Our results provide further insight into the mechanisms and physiological relevance of tissue-specific translational regulation.


Assuntos
Biossíntese de Proteínas , Ribossomos , Animais , Masculino , Camundongos , Músculo Esquelético/metabolismo , Elongação Traducional da Cadeia Peptídica , Proteínas Ribossômicas/genética , Proteínas Ribossômicas/metabolismo , Ribossomos/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
13.
J Vet Med Sci ; 85(4): 443-446, 2023 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-36806247

RESUMO

The geneLEAD VIII is a fully-automated nucleic acid extraction/quantitative PCR equipment developed by Precision System Science Co., Ltd., (PSS). To take advantage of its capability, we developed a quantitative assay system to measure growth of animal viruses. The system was used to assay one of the Chinese herbal extracts whose anti-malarial activities were previously reported and demonstrated its dose-dependent anti-viral activity against feline infectious peritonitis virus (FIPV), a feline coronavirus causing the fatal diseases in cats, and relatively low cell toxicity. The assay developed in this study is useful to screen antiviral drugs and the anti-FIPV activity of the herbal extract identified have a potential to lead to development of new drugs against FIPV and other coronaviruses, such as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).


Assuntos
Antineoplásicos , COVID-19 , Doenças do Gato , Coronavirus Felino , Peritonite , Animais , Gatos , Coronavirus Felino/genética , SARS-CoV-2/genética , COVID-19/veterinária , Antivirais/uso terapêutico , Reação em Cadeia da Polimerase/veterinária , Peritonite/veterinária , Teste para COVID-19/veterinária , Doenças do Gato/tratamento farmacológico
14.
Int J Mol Sci ; 24(1)2023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-36614280

RESUMO

Iron-sulfur (Fe-S) clusters are essential cofactors for enzyme activity. These Fe-S clusters are present in structurally diverse forms, including [4Fe-4S] and [3Fe-4S]. Type-identification of the Fe-S cluster is indispensable in understanding the catalytic mechanism of enzymes. However, identifying [4Fe-4S] and [3Fe-4S] clusters in particular is challenging because of their rapid transformation in response to oxidation-reduction events. In this study, we focused on the relationship between the Fe-S cluster type and the catalytic activity of a tRNA-thiolation enzyme (TtuA). We reconstituted [4Fe-4S]-TtuA, prepared [3Fe-4S]-TtuA by oxidizing [4Fe-4S]-TtuA under strictly anaerobic conditions, and then observed changes in the Fe-S clusters in the samples and the enzymatic activity in the time-course experiments. Electron paramagnetic resonance analysis revealed that [3Fe-4S]-TtuA spontaneously transforms into [4Fe-4S]-TtuA in minutes to one hour without an additional free Fe source in the solution. Although the TtuA immediately after oxidation of [4Fe-4S]-TtuA was inactive [3Fe-4S]-TtuA, its activity recovered to a significant level compared to [4Fe-4S]-TtuA after one hour, corresponding to an increase of [4Fe-4S]-TtuA in the solution. Our findings reveal that [3Fe-4S]-TtuA is highly inactive and unstable. Moreover, time-course analysis of structural changes and activity under strictly anaerobic conditions further unraveled the Fe-S cluster type used by the tRNA-thiolation enzyme.


Assuntos
Proteínas Ferro-Enxofre , Ferro , Ferro/química , Espectroscopia de Ressonância de Spin Eletrônica , Oxirredução , Enxofre/química , RNA de Transferência/química , Proteínas Ferro-Enxofre/metabolismo
15.
Drug Metab Dispos ; 51(2): 165-173, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36414408

RESUMO

The drug 5-fluorouracil (5-FU) is the first-choice chemotherapeutic agent against advanced-stage cancers. However, 10% to 30% of treated patients experience grade 3 to 4 toxicity. The deficiency of dihydropyrimidinase (DHPase), which catalyzes the second step of the 5-FU degradation pathway, is correlated with the risk of developing toxicity. Thus, genetic polymorphisms within DPYS, the DHPase-encoding gene, could potentially serve as predictors of severe 5-FU-related toxicity. We identified 12 novel DPYS variants in 3554 Japanese individuals, but the effects of these mutations on function remain unknown. In the current study, we performed in vitro enzymatic analyses of the 12 newly identified DHPase variants. Dihydrouracil or dihydro-5-FU hydrolytic ring-opening kinetic parameters, Km and Vmax , and intrinsic clearance (CLint = Vmax /Km ) of the wild-type DHPase and eight variants were measured. Five of these variants (R118Q, H295R, T418I, Y448H, and T513A) showed significantly reduced CLint compared with that in the wild-type. The parameters for the remaining four variants (V59F, D81H, T136M, and R490H) could not be determined as dihydrouracil and dihydro-5-FU hydrolytic ring-opening activity was undetectable. We also determined DHPase variant protein stability using cycloheximide and bortezomib. The mechanism underlying the observed changes in the kinetic parameters was clarified using blue-native polyacrylamide gel electrophoresis and three-dimensional structural modeling. The results suggested that the decrease or loss of DHPase enzymatic activity was due to reduced stability and oligomerization of DHPase variant proteins. Our findings support the use of DPYS polymorphisms as novel pharmacogenomic markers for predicting severe 5-FU-related toxicity in the Japanese population. SIGNIFICANCE STATEMENT: DHPase contributes to the degradation of 5-fluorouracil, and genetic polymorphisms that cause decreased activity of DHPase can cause severe toxicity. In this study, we performed functional analysis of 12 DHPase variants in the Japanese population and identified 9 genetic polymorphisms that cause reduced DHPase function. In addition, we found that the ability to oligomerize and the conformation of the active site are important for the enzymatic activity of DHPase.


Assuntos
População do Leste Asiático , Fluoruracila , Humanos , Amidoidrolases/metabolismo , Fluoruracila/efeitos adversos , Fluoruracila/metabolismo , Polimorfismo Genético/genética
16.
Vet Sci ; 9(12)2022 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-36548864

RESUMO

Due to the high incidence of mammary tumors in dogs, it is important to elucidate the pathogenesis of these tumors in veterinary medicine. Radiation therapy is often used to treat mammary tumors that target DNA lesions. RAD51 is a key molecule that repairs DNA damage via homologous recombination. We examined the relationship between RAD51 expression and radiosensitivity in mammary tumor cell lines. CHMp and CHMm from the same individual were selected based on the differences in RAD51 expression. The radiosensitivity of both cell lines was examined using MTT and scratch assays; CHMm, which has high RAD51 expression, showed higher sensitivity to radiation than CHMp. However, the nuclear focus of RAD51 during DNA repair was formed normally in CHMp, but not in most of CHMm. Since irradiation resulted in the suppression of cell cycle progression in CHMp, the expression of p21, a cell cycle regulatory factor, was detected in CHMp after 15 Gy irradiation but not in CHMm. These results indicate that functional expression is more important than the quantitative expression of RAD51 in canine mammary tumor cells in response to DNA damage.

17.
Nat Commun ; 13(1): 7262, 2022 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-36433967

RESUMO

N-glycan-mediated activation of the thrombopoietin receptor (MPL) under pathological conditions has been implicated in myeloproliferative neoplasms induced by mutant calreticulin, which forms an endogenous receptor-agonist complex that traffics to the cell surface and constitutively activates the receptor. However, the molecular basis for this mechanism is elusive because oncogenic activation occurs only in the cell-intrinsic complex and is thus cannot be replicated with external agonists. Here, we describe the structure and function of a marine sponge-derived MPL agonist, thrombocorticin (ThC), a homodimerized lectin with calcium-dependent fucose-binding properties. In-depth characterization of lectin-induced activation showed that, similar to oncogenic activation, sugar chain-mediated activation persists due to limited receptor internalization. The strong synergy between ThC and thrombopoietin suggests that ThC catalyzes the formation of receptor dimers on the cell surface. Overall, the existence of sugar-mediated MPL activation, in which the mode of activation is different from the original ligand, suggests that receptor activation is unpredictably diverse in living organisms.


Assuntos
Poríferos , Receptores de Trombopoetina , Animais , Lectinas , Poríferos/metabolismo , Receptores de Trombopoetina/metabolismo , Açúcares , Trombopoetina
18.
Viruses ; 14(8)2022 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-36016355

RESUMO

Feline coronaviruses (FCoVs) infect cats worldwide and cause severe systemic diseases, such as feline infectious peritonitis (FIP). FIP has a high mortality rate, and drugs approved by the Food and Drug Administration have been ineffective for the treatment of FIP. Investigating host factors and the functions required for FCoV replication is necessary to develop effective drugs for the treatment of FIP. FCoV utilizes an endosomal trafficking system for cellular entry after binding between the viral spike (S) protein and its receptor. The cellular enzymes that cleave the S protein of FCoV to release the viral genome into the cytosol require an acidic pH optimized in the endosomes by regulating cellular ion concentrations. Ionophore antibiotics are compounds that form complexes with alkali ions to alter the endosomal pH conditions. This study shows that ionophore antibiotics, including valinomycin, salinomycin, and nigericin, inhibit FCoV proliferation in vitro in a dose-dependent manner. These results suggest that ionophore antibiotics should be investigated further as potential broad-spectrum anti-FCoV agents.


Assuntos
Coronavirus Felino , Peritonite Infecciosa Felina , Animais , Antibacterianos/farmacologia , Gatos , Proliferação de Células , Coronavirus Felino/genética , Peritonite Infecciosa Felina/tratamento farmacológico , Ionóforos/farmacologia
19.
Nat Commun ; 13(1): 3974, 2022 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-35803942

RESUMO

In flowering plants, strigolactones (SLs) have dual functions as hormones that regulate growth and development, and as rhizosphere signaling molecules that induce symbiosis with arbuscular mycorrhizal (AM) fungi. Here, we report the identification of bryosymbiol (BSB), an SL from the bryophyte Marchantia paleacea. BSB is also found in vascular plants, indicating its origin in the common ancestor of land plants. BSB synthesis is enhanced at AM symbiosis permissive conditions and BSB deficient mutants are impaired in AM symbiosis. In contrast, the absence of BSB synthesis has little effect on the growth and gene expression. We show that the introduction of the SL receptor of Arabidopsis renders M. paleacea cells BSB-responsive. These results suggest that BSB is not perceived by M. paleacea cells due to the lack of cognate SL receptors. We propose that SLs originated as AM symbiosis-inducing rhizosphere signaling molecules and were later recruited as plant hormone.


Assuntos
Arabidopsis , Micorrizas , Arabidopsis/genética , Arabidopsis/metabolismo , Compostos Heterocíclicos com 3 Anéis , Lactonas/metabolismo , Micorrizas/genética , Micorrizas/metabolismo , Raízes de Plantas/metabolismo , Rizosfera , Simbiose
20.
Gan To Kagaku Ryoho ; 49(5): 563-567, 2022 May.
Artigo em Japonês | MEDLINE | ID: mdl-35578935

RESUMO

In 2018, the World Health Organization revised its cancer pain therapy, abolishing the three-step pain relief ladder and recommending the use of opioid analgesics(OA)according to the pain intensity. Of opioid naive patients who were admitted to Chibaken Saiseikai Narashino Hospital from July 2015 to June 2017, treatment with weak OA was initiated in 13 patients(WOA group)and low-dose strong OA in 12 patients(SOA group). The numerical rating scale values immediately before the start of OA and 3, 7 and 14 days later were not significantly different between the 2 groups. As for adverse events, the frequency of occurrence(p=0.01)and the prolongation of the last onset date(p=0.02)were significant in the WOA group for constipation. When the factors related to OA selection were analyzed using logistic regression analysis, there was no significance. We reported the analysis results regarding OA selection in OA naive patients.


Assuntos
Dor do Câncer , Neoplasias , Analgésicos Opioides/uso terapêutico , Dor do Câncer/tratamento farmacológico , Humanos , Hiperplasia , Neoplasias/induzido quimicamente , Neoplasias/complicações , Neoplasias/tratamento farmacológico , Dor/induzido quimicamente , Dor/etiologia , Medição da Dor
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