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1.
Nat Immunol ; 22(8): 1020-1029, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34312547

RESUMEN

T cell exhaustion is an induced state of dysfunction that arises in response to chronic infection and cancer. Exhausted CD8+ T cells acquire a distinct epigenetic state, but it is not known whether that chromatin landscape is fixed or plastic following the resolution of a chronic infection. Here we show that the epigenetic state of exhaustion is largely irreversible, even after curative therapy. Analysis of chromatin accessibility in HCV- and HIV-specific responses identifies a core epigenetic program of exhaustion in CD8+ T cells, which undergoes only limited remodeling before and after resolution of infection. Moreover, canonical features of exhaustion, including super-enhancers near the genes TOX and HIF1A, remain 'epigenetically scarred.' T cell exhaustion is therefore a conserved epigenetic state that becomes fixed and persists independent of chronic antigen stimulation and inflammation. Therapeutic efforts to reverse T cell exhaustion may require new approaches that increase the epigenetic plasticity of exhausted T cells.


Asunto(s)
Antígenos Virales/inmunología , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/patología , Hepacivirus/inmunología , Hepatitis C Crónica/inmunología , Memoria Inmunológica/inmunología , 2-Naftilamina/uso terapéutico , Anilidas/uso terapéutico , Antivirales/uso terapéutico , Cromatina/metabolismo , Ciclopropanos/uso terapéutico , Epigénesis Genética/genética , Hepacivirus/efectos de los fármacos , Hepatitis C Crónica/tratamiento farmacológico , Proteínas del Grupo de Alta Movilidad/genética , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Lactamas Macrocíclicas/uso terapéutico , Prolina/análogos & derivados , Prolina/uso terapéutico , Ribavirina/uso terapéutico , Ritonavir/uso terapéutico , Sulfonamidas/uso terapéutico , Uracilo/análogos & derivados , Uracilo/uso terapéutico , Valina/uso terapéutico
2.
Nature ; 601(7893): 428-433, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34937946

RESUMEN

Although deregulation of transfer RNA (tRNA) biogenesis promotes the translation of pro-tumorigenic mRNAs in cancers1,2, the mechanisms and consequences of tRNA deregulation in tumorigenesis are poorly understood. Here we use a CRISPR-Cas9 screen to focus on genes that have been implicated in tRNA biogenesis, and identify a mechanism by which altered valine tRNA biogenesis enhances mitochondrial bioenergetics in T cell acute lymphoblastic leukaemia (T-ALL). Expression of valine aminoacyl tRNA synthetase is transcriptionally upregulated by NOTCH1, a key oncogene in T-ALL, underlining a role for oncogenic transcriptional programs in coordinating tRNA supply and demand. Limiting valine bioavailability through restriction of dietary valine intake disrupted this balance in mice, resulting in decreased leukaemic burden and increased survival in vivo. Mechanistically, valine restriction reduced translation rates of mRNAs that encode subunits of mitochondrial complex I, leading to defective assembly of complex I and impaired oxidative phosphorylation. Finally, a genome-wide CRISPR-Cas9 loss-of-function screen in differential valine conditions identified several genes, including SLC7A5 and BCL2, whose genetic ablation or pharmacological inhibition synergized with valine restriction to reduce T-ALL growth. Our findings identify tRNA deregulation as a critical adaptation in the pathogenesis of T-ALL and provide a molecular basis for the use of dietary approaches to target tRNA biogenesis in blood malignancies.


Asunto(s)
Leucemia-Linfoma Linfoblástico de Células T Precursoras , Valina-ARNt Ligasa , Valina , Animales , Disponibilidad Biológica , Sistemas CRISPR-Cas , Dieta , Complejo I de Transporte de Electrón/genética , Transportador de Aminoácidos Neutros Grandes 1 , Ratones , Mitocondrias/metabolismo , Fosforilación Oxidativa , Leucemia-Linfoma Linfoblástico de Células T Precursoras/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2 , ARN de Transferencia/genética , Valina/metabolismo , Valina-ARNt Ligasa/metabolismo
3.
N Engl J Med ; 388(10): 898-912, 2023 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-36884323

RESUMEN

BACKGROUND: Desmoid tumors are rare, locally aggressive, highly recurrent soft-tissue tumors without approved treatments. METHODS: We conducted a phase 3, international, double-blind, randomized, placebo-controlled trial of nirogacestat in adults with progressing desmoid tumors according to the Response Evaluation Criteria in Solid Tumors, version 1.1. Patients were assigned in a 1:1 ratio to receive the oral γ-secretase inhibitor nirogacestat (150 mg) or placebo twice daily. The primary end point was progression-free survival. RESULTS: From May 2019 through August 2020, a total of 70 patients were assigned to receive nirogacestat and 72 to receive placebo. Nirogacestat had a significant progression-free survival benefit over placebo (hazard ratio for disease progression or death, 0.29; 95% confidence interval, 0.15 to 0.55; P<0.001); the likelihood of being event-free at 2 years was 76% with nirogacestat and 44% with placebo. Between-group differences in progression-free survival were consistent across prespecified subgroups. The percentage of patients who had an objective response was significantly higher with nirogacestat than with placebo (41% vs. 8%; P<0.001), with a median time to response of 5.6 months and 11.1 months, respectively; the percentage of patients with a complete response was 7% and 0%, respectively. Significant between-group differences in secondary patient-reported outcomes, including pain, symptom burden, physical or role functioning, and health-related quality of life, were observed (P≤0.01). Frequent adverse events with nirogacestat included diarrhea (in 84% of the patients), nausea (in 54%), fatigue (in 51%), hypophosphatemia (in 42%), and maculopapular rash (in 32%); 95% of adverse events were of grade 1 or 2. Among women of childbearing potential receiving nirogacestat, 27 of 36 (75%) had adverse events consistent with ovarian dysfunction, which resolved in 20 women (74%). CONCLUSIONS: Nirogacestat was associated with significant benefits with respect to progression-free survival, objective response, pain, symptom burden, physical functioning, role functioning, and health-related quality of life in adults with progressing desmoid tumors. Adverse events with nirogacestat were frequent but mostly low grade. (Funded by SpringWorks Therapeutics; DeFi ClinicalTrials.gov number, NCT03785964.).


Asunto(s)
Antineoplásicos , Fibromatosis Agresiva , Inhibidores y Moduladores de Gamma Secretasa , Tetrahidronaftalenos , Adulto , Femenino , Humanos , Secretasas de la Proteína Precursora del Amiloide/uso terapéutico , Antineoplásicos/uso terapéutico , Método Doble Ciego , Fibromatosis Agresiva/tratamiento farmacológico , Inhibidores y Moduladores de Gamma Secretasa/uso terapéutico , Supervivencia sin Progresión , Calidad de Vida , Tetrahidronaftalenos/uso terapéutico , Valina/análogos & derivados
4.
Nature ; 586(7828): 317-321, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32640464

RESUMEN

Acetohydroxyacid synthase (AHAS), also known as acetolactate synthase, is a flavin adenine dinucleotide-, thiamine diphosphate- and magnesium-dependent enzyme that catalyses the first step in the biosynthesis of branched-chain amino acids1. It is the target for more than 50 commercial herbicides2. AHAS requires both catalytic and regulatory subunits for maximal activity and functionality. Here we describe structures of the hexadecameric AHAS complexes of Saccharomyces cerevisiae and dodecameric AHAS complexes of Arabidopsis thaliana. We found that the regulatory subunits of these AHAS complexes form a core to which the catalytic subunit dimers are attached, adopting the shape of a Maltese cross. The structures show how the catalytic and regulatory subunits communicate with each other to provide a pathway for activation and for feedback inhibition by branched-chain amino acids. We also show that the AHAS complex of Mycobacterium tuberculosis adopts a similar structure, thus demonstrating that the overall AHAS architecture is conserved across kingdoms.


Asunto(s)
Acetolactato Sintasa/química , Arabidopsis/enzimología , Saccharomyces cerevisiae/enzimología , Acetolactato Sintasa/metabolismo , Adenosina Trifosfato/metabolismo , Aminoácidos de Cadena Ramificada/biosíntesis , Dominio Catalítico , Activación Enzimática , Evolución Molecular , Retroalimentación Fisiológica , Modelos Moleculares , Complejos Multiproteicos/química , Complejos Multiproteicos/metabolismo , Mycobacterium tuberculosis/enzimología , Unión Proteica , Conformación Proteica , Subunidades de Proteína/química , Subunidades de Proteína/metabolismo , Valina/metabolismo
5.
Proc Natl Acad Sci U S A ; 120(9): e2221529120, 2023 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-36812212

RESUMEN

Mammalian telomeres consist of (TTAGGG)n repeats. Transcription of the C-rich strand generates a G-rich RNA, termed TERRA, containing G-quadruplex structures. Recent discoveries in several human nucleotide expansion diseases revealed that RNA transcripts containing long runs of 3 or 6 nt repeats which can form strong secondary structures can be translated in multiple frames to generate homopeptide or dipeptide repeat proteins, and multiple studies have shown them to be toxic in cells. We noted that the translation of TERRA would generate two dipeptide repeat proteins: highly charged repeating valine-arginine (VR)n and hydrophobic repeating glycine-leucine (GL)n. Here, we synthesized these two dipeptide proteins and raised polyclonal antibodies to VR. The VR dipeptide repeat protein binds nucleic acids and localizes strongly to replication forks in DNA. Both VR and GL form long 8-nm filaments with amyloid properties. Using labeled antibodies to VR and laser scanning confocal microscopy, threefold to fourfold more VR was observed in the nuclei of cell lines containing elevated TERRA as contrasted to a primary fibroblast line. Induction of telomere dysfunction via knockdown of TRF2 led to higher amounts of VR, and alteration of TERRA levels using a locked nucleic acid (LNA) GapmeR led to large nuclear VR aggregates. These observations suggest that telomeres, in particular in cells undergoing telomere dysfunction, may express two dipeptide repeat proteins with potentially strong biological properties.


Asunto(s)
Arginina , ARN , Animales , Humanos , ARN/metabolismo , Leucina/genética , Arginina/genética , Valina , Dipéptidos/genética , Telómero/metabolismo , Mamíferos/genética
6.
Plant Physiol ; 194(4): 2755-2770, 2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38235781

RESUMEN

Apple Valsa canker (AVC) is a devastating disease of apple (Malus × domestica), caused by Valsa mali (Vm). The Cysteine-rich secretory protein, Antigen 5, and Pathogenesis-related protein 1 (CAP) superfamily protein PATHOGENESIS-RELATED PROTEIN 1-LIKE PROTEIN c (VmPR1c) plays an important role in the pathogenicity of Vm. However, the mechanisms through which it exerts its virulence function in Vm-apple interactions remain unclear. In this study, we identified an apple valine-glutamine (VQ)-motif-containing protein, MdVQ29, as a VmPR1c target protein. MdVQ29-overexpressing transgenic apple plants showed substantially enhanced AVC resistance as compared with the wild type. MdVQ29 interacted with the transcription factor MdWRKY23, which was further shown to bind to the promoter of the jasmonic acid (JA) signaling-related gene CORONATINE INSENSITIVE 1 (MdCOI1) and activate its expression to activate the JA signaling pathway. Disease evaluation in lesion areas on infected leaves showed that MdVQ29 positively modulated apple resistance in a MdWRKY23-dependent manner. Furthermore, MdVQ29 promoted the transcriptional activity of MdWRKY23 toward MdCOI1. In addition, VmPR1c suppressed the MdVQ29-enhanced transcriptional activation activity of MdWRKY23 by promoting the degradation of MdVQ29 and inhibiting MdVQ29 expression and the MdVQ29-MdWRKY23 interaction, thereby interfering with the JA signaling pathway and facilitating Vm infection. Overall, our results demonstrate that VmPR1c targets MdVQ29 to manipulate the JA signaling pathway to regulate immunity. Thus, this study provides an important theoretical basis and guidance for mining and utilizing disease-resistance genetic resources for genetically improving apples.


Asunto(s)
Ascomicetos , Ciclopentanos , Malus , Oxilipinas , Malus/genética , Malus/metabolismo , Glutamina/metabolismo , Valina/metabolismo , Transducción de Señal , Enfermedades de las Plantas/genética
7.
J Am Chem Soc ; 146(8): 5550-5559, 2024 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-38364824

RESUMEN

OspD is a radical S-adenosyl-l-methionine (SAM) peptide epimerase that converts an isoleucine (Ile) and valine (Val) of the OspA substrate to d-amino acids during biosynthesis of the ribosomally synthesized and post-translationally modified peptide (RiPP) natural product landornamide A. OspD is proposed to carry out this reaction via α-carbon (Cα) H-atom abstraction to form a peptidyl Cα radical that is stereospecifically quenched by hydrogen atom transfer (HAT) from a conserved cysteine (Cys). Here we use site-directed mutagenesis, freeze-quench trapping, isotopic labeling, and electron paramagnetic resonance (EPR) spectroscopy to provide new insights into the OspD catalytic mechanism including the direct observation of the substrate peptide Cα radical intermediate. The putative quenching Cys334 was changed to serine to generate an OspD C334S variant impaired in HAT quenching. The reaction of reduced OspD C334S with SAM and OspA freeze-quenched at 15 s exhibits a doublet EPR signal characteristic of a Cα radical coupled to a single ß-H. Using isotopologues of OspA deuterated at either Ile or Val, or both Ile and Val, reveals that the initial Cα radical intermediate forms exclusively on the Ile of OspA. Time-dependent freeze quench coupled with EPR spectroscopy provided evidence for loss of the Ile Cα radical concomitant with gain of a Val Cα radical, directly demonstrating the N-to-C directionality of epimerization by OspD. These results provide direct evidence for the aforementioned OspD-catalyzed peptide epimerization mechanism via a central Cα radical intermediate during RiPP maturation of OspA, a mechanism that may extend to other proteusin peptide epimerases.


Asunto(s)
Metionina , S-Adenosilmetionina , S-Adenosilmetionina/química , Carbono , Péptidos/química , Aminoácidos , Racemetionina , Valina
8.
Antimicrob Agents Chemother ; 68(7): e0000824, 2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-38767383

RESUMEN

Ravidasvir (RDV) is a novel NS5A inhibitor that exhibits potent pan-genotypic inhibition of hepatitis C virus (HCV) replication. Sofosbuvir (SOF) plus RDV was demonstrated to be efficacious and safe in adults with active HCV infection, including those living with HIV (LWHIV), in the STORM-C-1 trial. We assessed the population pharmacokinetics (PK) of RDV in a sub-study nested within STORM-C-1 conducted in Thailand and Malaysia. SOF (400 mg) plus RDV (200 mg) was administered orally once daily for 12 weeks to adults with chronic HCV infection, but without cirrhosis and for 24 weeks to those with compensated cirrhosis. Intensive and sparse PK samples were collected at 4, 8, and 12 weeks after treatment initiation. Population PK parameters of RDV and the impact of covariates were evaluated using nonlinear mixed-effects modeling. Five hundred ninety-four participants were included, 235 (40%) had compensated cirrhosis, and 189 (32%) were LWHIV. RDV plasma concentrations were best described by a two-compartment model with first-order elimination. Oral clearance (CL/F) and volume of distribution (Vd/F) parameters were allometrically scaled on fat-free mass. Concomitant antiretroviral treatment (ART) increased RDV CL/F by 30%-60%, with efavirenz-based ART having the largest impact. Females had 16% lower RDV CL/F than males, and higher albumin levels reduced RDV central volume of distribution. While several covariates impact RDV CL/F and Vd/F, the effect on RDV exposures was not clinically relevant based on the efficacy data reported in this diverse Asian adult population. There were no meaningful drug-drug interactions in adults LWHIV on ART.


Asunto(s)
Antivirales , Infecciones por VIH , Hepatitis C Crónica , Valina , Humanos , Masculino , Femenino , Hepatitis C Crónica/tratamiento farmacológico , Persona de Mediana Edad , Adulto , Antivirales/farmacocinética , Antivirales/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/virología , Valina/farmacocinética , Valina/análogos & derivados , Sofosbuvir/farmacocinética , Sofosbuvir/uso terapéutico , Ciclopropanos , Hepacivirus/efectos de los fármacos , Hepacivirus/genética , Alquinos , Tailandia , Benzoxazinas/farmacocinética , Benzoxazinas/uso terapéutico , Cirrosis Hepática/tratamiento farmacológico , Quimioterapia Combinada , Bencimidazoles
9.
Anal Chem ; 96(32): 13166-13173, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39092810

RESUMEN

For the approval of a drug, the stability data must be submitted to regulatory authorities. Such analyses are often time-consuming and cost-intensive. Forced degradation studies are mainly carried out under harsh conditions in the dissolved state, often leading to extraneous degradation profiles for a solid drug. Oxidative mechanochemical degradation offers the possibility of generating realistic degradation profiles. In this study, a sustainable mechanochemical procedure is presented for the degradation of five active pharmaceutical ingredients (APIs) from the sartan family: losartan potassium, irbesartan, valsartan, olmesartan medoxomil, and telmisartan. High-resolution mass spectrometry enabled the detection of impurities already present in untreated APIs and allowed the elucidation of degradation products. Significant degradation profiles could already be obtained after 15-60 min of ball milling time. Many of the identified degradation products are described in the literature and pharmacopoeias, emphasizing the significance of our results and the applicability of this approach to predict degradation profiles for drugs in the solid state.


Asunto(s)
Bencimidazoles , Compuestos de Bifenilo , Losartán , Telmisartán , Tetrazoles , Valsartán , Bencimidazoles/química , Bencimidazoles/análisis , Tetrazoles/química , Telmisartán/química , Valsartán/química , Losartán/química , Losartán/análisis , Compuestos de Bifenilo/química , Irbesartán/química , Irbesartán/análisis , Imidazoles/química , Benzoatos/química , Valina/química , Valina/análisis , Solventes/química , Estabilidad de Medicamentos
10.
Chembiochem ; 25(6): e202300762, 2024 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-38294275

RESUMEN

Precise information regarding the interaction between proteins and ligands at molecular resolution is crucial for effectively guiding the optimization process from initial hits to lead compounds in early stages of drug development. In this study, we introduce a novel aliphatic side chain isotope-labeling scheme to directly probe interactions between ligands and aliphatic sidechains using NMR techniques. To demonstrate the applicability of this method, we selected a set of Brd4-BD1 binders and analyzed 1 H chemical shift perturbation resulting from CH-π interaction of Hß -Val and Hγ -Leu as CH donors with corresponding ligand aromatic moieties as π acceptors.


Asunto(s)
Proteínas Nucleares , Valina , Leucina/química , Valina/química , Ligandos , Factores de Transcripción
11.
Cancer Causes Control ; 35(2): 323-334, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37737303

RESUMEN

PURPOSE OF THE STUDY: Breast density is an established risk factor for breast cancer. However, little is known about metabolic influences on breast density phenotypes. We conducted untargeted serum metabolomics analyses to identify metabolic signatures associated with breast density phenotypes among young women. METHODS: In a cross-sectional study of 173 young women aged 25-29 who participated in the Dietary Intervention Study in Children 2006 Follow-up Study, 449 metabolites were measured in fasting serum samples using ultra-high-performance liquid chromatography-tandem mass spectrometry. Multivariable-adjusted mixed-effects linear regression identified metabolites associated with magnetic resonance imaging measured breast density phenotypes: percent dense breast volume (%DBV), absolute dense breast volume (ADBV), and absolute non-dense breast volume (ANDBV). Metabolite results were corrected for multiple comparisons using a false discovery rate adjusted p-value (q). RESULTS: The amino acids valine and leucine were significantly inversely associated with %DBV. For each 1 SD increase in valine and leucine, %DBV decreased by 20.9% (q = 0.02) and 18.4% (q = 0.04), respectively. ANDBV was significantly positively associated with 16 lipid and one amino acid metabolites, whereas no metabolites were associated with ADBV. Metabolite set enrichment analysis also revealed associations of distinct metabolic signatures with %DBV, ADBV, and ANDBV; branched chain amino acids had the strongest inverse association with %DBV (p = 0.002); whereas, diacylglycerols and phospholipids were positively associated with ANDBV (p ≤ 0.002), no significant associations were observed for ADBV. CONCLUSION: Our results suggest an inverse association of branched chain amino acids with %DBV. Larger studies in diverse populations are needed.


Asunto(s)
Densidad de la Mama , Neoplasias de la Mama , Niño , Femenino , Humanos , Leucina , Estudios Transversales , Estudios de Seguimiento , Mamografía , Aminoácidos de Cadena Ramificada , Valina
12.
Brief Bioinform ; 23(5)2022 09 20.
Artículo en Inglés | MEDLINE | ID: mdl-35598329

RESUMEN

Many statistical methods for pathway analysis have been used to identify pathways associated with the disease along with biological factors such as genes and proteins. However, most pathway analysis methods neglect the complex nonlinear relationship between biological factors and pathways. In this study, we propose a Deep-learning pathway analysis using Hierarchical structured CoMponent models (DeepHisCoM) that utilize deep learning to consider a nonlinear complex contribution of biological factors to pathways by constructing a multilayered model which accounts for hierarchical biological structure. Through simulation studies, DeepHisCoM was shown to have a higher power in the nonlinear pathway effect and comparable power for the linear pathway effect when compared to the conventional pathway methods. Application to hepatocellular carcinoma (HCC) omics datasets, including metabolomic, transcriptomic and metagenomic datasets, demonstrated that DeepHisCoM successfully identified three well-known pathways that are highly associated with HCC, such as lysine degradation, valine, leucine and isoleucine biosynthesis and phenylalanine, tyrosine and tryptophan. Application to the coronavirus disease-2019 (COVID-19) single-nucleotide polymorphism (SNP) dataset also showed that DeepHisCoM identified four pathways that are highly associated with the severity of COVID-19, such as mitogen-activated protein kinase (MAPK) signaling pathway, gonadotropin-releasing hormone (GnRH) signaling pathway, hypertrophic cardiomyopathy and dilated cardiomyopathy. Codes are available at https://github.com/chanwoo-park-official/DeepHisCoM.


Asunto(s)
COVID-19 , Carcinoma Hepatocelular , Aprendizaje Profundo , Neoplasias Hepáticas , Humanos , Factores Biológicos , Carcinoma Hepatocelular/genética , Hormona Liberadora de Gonadotropina , Isoleucina , Leucina , Lisina , Proteínas Quinasas Activadas por Mitógenos , Fenilalanina , Triptófano , Tirosina , Valina
13.
Am J Physiol Regul Integr Comp Physiol ; 327(2): R261-R273, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38881412

RESUMEN

Central administration of valine has been shown to cause hyperphagia in fish. Although mechanistic target of rapamycin (mTOR) is involved in this response, the contributions to feed intake of central and peripheral metabolite changes due to excess valine are unknown. Here, we investigated whether intracerebroventricular injection of valine modulates central and peripheral metabolite profiles and may provide insights into feeding response in fish. Juvenile rainbow trout (Oncorhynchus mykiss) were administered an intracerebroventricular injection of valine (10 µg·µL-1 at 1 µL·100·g-1 body wt), and the metabolite profile in plasma, hypothalamus, and rest of the brain (composing of telencephalon, optic tectum, cerebellum, and medulla oblongata) was carried out by liquid chromatography-mass spectrometry (LC/MS)-based metabolomics. Valine administration led to a spatially distinct metabolite profile at 1 h postinjection in the brain: enrichment of amino acid metabolism and energy production pathways in the rest of the brain but not in hypothalamus. This suggests a role for extrahypothalamic input in the regulation of feed intake. Also, there was enrichment of several amino acids, including tyrosine, proline, valine, phenylalanine, and methionine, in plasma in response to valine. Changes in liver transcript abundance and protein expression reflect an increased metabolic capacity, including energy production from glucose and fatty acids, and a lower protein kinase B (Akt) phosphorylation in the valine group. Altogether, valine intracerebroventricular administration affects central and peripheral metabolism in rainbow trout, and we propose a role for the altered metabolite profile in modulating the feeding response to this branched-chain amino acid.NEW & NOTEWORTHY Valine causes hyperphagia in fish when it is centrally administered; however, the exact mechanisms are far from clear. We tested how intracerebroventricular injection of valine in rainbow trout affected the brain and plasma metabolome. The metabolite changes in response to valine were more evident in the rest of the brain compared with the hypothalamus. Furthermore, we demonstrated for the first time that central valine administration affects peripheral metabolism in rainbow trout.


Asunto(s)
Hipotálamo , Oncorhynchus mykiss , Valina , Animales , Oncorhynchus mykiss/metabolismo , Oncorhynchus mykiss/sangre , Valina/farmacología , Valina/administración & dosificación , Hipotálamo/metabolismo , Hipotálamo/efectos de los fármacos , Metaboloma/efectos de los fármacos , Encéfalo/metabolismo , Encéfalo/efectos de los fármacos , Metabolómica , Inyecciones Intraventriculares , Metabolismo Energético/efectos de los fármacos
14.
J Viral Hepat ; 31(8): 500-503, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38771312

RESUMEN

Hepatitis C virus core antigen (HCVcAg) testing can simplify and decrease costs of HCV infection confirmation compared to molecular testing (nucleic acid testing). We piloted HCVcAg testing for the confirmation of active infection. The study was conducted during June through December 2022 among the police and the general population of Islamabad, Pakistan age 18 years and older. Initial screening for HCV antibody was conducted using a rapid diagnostic test (RDT) for all consenting participants. Those who tested positive had venous blood samples tested for HCVcAg, platelets and aspartate aminotransferase (AST). Persons with HCVcAg values ≥3 fmol/L were defined as viremic, and they were offered treatment with direct acting antiviral (DAA) medications, sofosbuvir and daclatasvir. Aspartate aminotransferase to platelet ratio index (APRI) was calculated for each HCV infected person, and those with an APRI score <1.5 received treatment for 12 weeks, while those with APRI ≥ to 1.5 received 24 weeks of treatment. A total of 15,628 persons were screened for anti-HCV using RDT and 643 (4.1%) tested positive. HCVcAg values of ≥3 fmol/L was found in 399/643 (62.1%), and all were offered and accepted treatment. Of those treated, 273/399 (68.4%) returned for a follow-up SVR and HCVcAg was not detected in 261/273, a 95.6% cure rate. The pilot study demonstrated the effectiveness of reaching and treating an urban population using RDT for screening and HCVcAg for confirmation of infection and test of cure.


Asunto(s)
Antivirales , Hepacivirus , Hepatitis C , Policia , Humanos , Pakistán/epidemiología , Masculino , Femenino , Adulto , Persona de Mediana Edad , Antivirales/uso terapéutico , Hepatitis C/diagnóstico , Hepatitis C/tratamiento farmacológico , Hepacivirus/genética , Hepacivirus/inmunología , Adulto Joven , Proteínas del Núcleo Viral/sangre , Antígenos de la Hepatitis C/sangre , Anciano , Adolescente , Proyectos Piloto , Tamizaje Masivo/métodos , Anticuerpos contra la Hepatitis C/sangre , Carbamatos , Imidazoles , Pirrolidinas , Valina/análogos & derivados
15.
Bioconjug Chem ; 35(3): 312-323, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38420925

RESUMEN

Developing effective amyloidosis inhibitors poses a significant challenge due to the dynamic nature of the protein structures, the complex interplay of interfaces in protein-protein interactions, and the irreversible nature of amyloid assembly. The interactions of amyloidogenic polypeptides with other peptides play a pivotal role in modulating amyloidosis and fibril formation. This study presents a novel approach for designing and synthesizing amyloid interaction surfaces using segments derived from the amyloid-promoting sequence of amyloid ß-peptide [VF(Aß(18-19)/FF(Aß(19-20)/LVF(Aß(17-19)/LVFF(Aß(17-20)], where VF, FF, LVF and LVFF stands for valine phenylalanine dipeptide, phenylalanine phenylalanine dipeptide, leucine valine phenylalanine tripeptide and leucine valine phenylalanine phenylalanine tetrapeptide, respectively. These segments are conjugated with side-chain proline-based methacrylate polymers serving as potent lysozyme amyloidosis inhibitors and demonstrating reduced cytotoxicity of amyloid aggregations. Di-, tri-, and tetra-peptide conjugated chain transfer agents (CTAs) were synthesized and used for the reversible addition-fragmentation chain transfer polymerization of tert-butoxycarbonyl (Boc)-proline methacryloyloxyethyl ester (Boc-Pro-HEMA). Deprotection of Boc-groups from the side-chain proline pendants resulted in water-soluble polymers with defined peptide chain ends as peptide-polymer bioconjugates. Among them, the LVFF-conjugated polymer acted as a potent inhibitor with significantly suppressed lysozyme amyloidosis, a finding supported by comprehensive spectroscopic, microscopic, and computational analyses. These results unveil the synergistic effect between the segment-derived amyloid ß-peptide and side-chain proline-based polymers, offering new prospects for targeting lysozyme amyloidosis.


Asunto(s)
Péptidos beta-Amiloides , Amiloidosis , Humanos , Péptidos beta-Amiloides/química , Prolina , Leucina , Polímeros/química , Muramidasa , Amiloidosis/tratamiento farmacológico , Amiloidosis/metabolismo , Amiloide , Dipéptidos/farmacología , Fenilalanina , Valina
16.
Metabolomics ; 20(1): 12, 2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-38180611

RESUMEN

INTRODUCTION: Alzheimer's Disease (AD) is complex and novel approaches are urgently needed to aid in diagnosis. Blood is frequently used as a source for biomarkers; however, its complexity prevents proper detection. The analytical power of metabolomics, coupled with statistical tools, can assist in reducing this complexity. OBJECTIVES: Thus, we sought to validate a previously proposed panel of metabolic blood-based biomarkers for AD and expand our understanding of the pathological mechanisms involved in AD that are reflected in the blood. METHODS: In the validation cohort serum and plasma were collected from 25 AD patients and 25 healthy controls. Serum was analysed for metabolites using nuclear magnetic resonance (NMR) spectroscopy, while plasma was tested for markers of neuronal damage and AD hallmark proteins using single molecule array (SIMOA). RESULTS: The diagnostic performance of the metabolite biomarker panel was confirmed using sparse-partial least squares discriminant analysis (sPLS-DA) with an area under the curve (AUC) of 0.73 (95% confidence interval: 0.59-0.87). Pyruvic acid and valine were consistently reduced in the discovery and validation cohorts. Pathway analysis of significantly altered metabolites in the validation set revealed that they are involved in branched-chain amino acids (BCAAs) and energy metabolism (glycolysis and gluconeogenesis). Additionally, strong positive correlations were observed for valine and isoleucine between cerebrospinal fluid p-tau and t-tau. CONCLUSIONS: Our proposed panel of metabolites was successfully validated using a combined approach of NMR and sPLS-DA. It was discovered that cognitive-impairment-related metabolites belong to BCAAs and are involved in energy metabolism.


Asunto(s)
Enfermedad de Alzheimer , Aminoácidos , Humanos , Enfermedad de Alzheimer/diagnóstico , Metabolómica , Aminoácidos de Cadena Ramificada , Valina , Biomarcadores
17.
Metabolomics ; 20(2): 24, 2024 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-38393619

RESUMEN

INTRODUCTION: Thiazolidinediones (TZDs), represented by pioglitazone and rosiglitazone, are a class of cost-effective oral antidiabetic agents posing a marginal hypoglycaemia risk. Nevertheless, observations of heart failure have hindered the clinical use of both therapies. OBJECTIVE: Since the mechanism of TZD-induced heart failure remains largely uncharacterised, this study aimed to explore the as-yet-unidentified mechanisms underpinning TZD cardiotoxicity using a toxicometabolomics approach. METHODS: The present investigation included an untargeted liquid chromatography-mass spectrometry-based toxicometabolomics pipeline, followed by multivariate statistics and pathway analyses to elucidate the mechanism(s)of TZD-induced cardiotoxicity using AC16 human cardiomyocytes as a model, and to identify the prognostic features associated with such effects. RESULTS: Acute administration of either TZD agent resulted in a significant modulation in carnitine content, reflecting potential disruption of the mitochondrial carnitine shuttle. Furthermore, perturbations were noted in purine metabolism and amino acid fingerprints, strongly conveying aberrations in cardiac energetics associated with TZD usage. Analysis of our findings also highlighted alterations in polyamine (spermine and spermidine) and amino acid (L-tyrosine and valine) metabolism, known modulators of cardiac hypertrophy, suggesting a potential link to TZD cardiotoxicity that necessitates further research. In addition, this comprehensive study identified two groupings - (i) valine and creatine, and (ii) L-tryptophan and L-methionine - that were significantly enriched in the above-mentioned mechanisms, emerging as potential fingerprint biomarkers for pioglitazone and rosiglitazone cardiotoxicity, respectively. CONCLUSION: These findings demonstrate the utility of toxicometabolomics in elaborating on mechanisms of drug toxicity and identifying potential biomarkers, thus encouraging its application in the toxicological sciences. (245 words).


Asunto(s)
Diabetes Mellitus Tipo 2 , Insuficiencia Cardíaca , Tiazolidinedionas , Humanos , Rosiglitazona/uso terapéutico , Pioglitazona , Miocitos Cardíacos , Cardiotoxicidad/complicaciones , Cardiotoxicidad/tratamiento farmacológico , Diabetes Mellitus Tipo 2/complicaciones , Metabolómica , Tiazolidinedionas/toxicidad , Insuficiencia Cardíaca/inducido químicamente , Aminoácidos , Biomarcadores , Carnitina , Valina
18.
J Clin Psychopharmacol ; 44(4): 353-361, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38767901

RESUMEN

PURPOSE/BACKGROUND: Using data from KINECT® 4, a phase 3, 48-week study of valbenazine, post hoc analyses were conducted to assess long-term outcomes that are relevant to the real-world management of tardive dyskinesia (TD). METHODS/PROCEDURES: Post hoc analyses of the participants of the KINECT 4 study who completed 48 weeks of open-label valbenazine (40 or 80 mg) treatment were conducted. Valbenazine effects on TD were evaluated using the Abnormal Involuntary Movement Scale (AIMS), Clinical Global Impression of Change-TD (CGI-TD), and Patient Global Impression of Change (PGIC). FINDINGS/RESULTS: Of 103 participants completing 48 weeks of treatment, 55% experienced clinically meaningful improvement (defined as ≥2-point reduction in AIMS total score [sum of items 1 - 7, evaluated by site raters]) by week 4; at week 48, 97% met this threshold. The percentage of completers who achieved AIMS total score response thresholds of ≥10% to ≥90% increased over time, with 86% of completers reaching ≥50% improvement. Of the 40 (39%) completers with AIMS ≥50% response at week 8, 38 (95%) sustained this response at week 48; 81% of those who did not meet this threshold at week 8 had achieved it by week 48. At week 48, more than 85% of completers achieved CGI-TD and PGIC ratings of "much improved" or "very much improved." IMPLICATIONS/CONCLUSIONS: The majority of participants who completed 48 weeks of treatment with once-daily valbenazine experienced substantial clinically meaningful and sustained TD improvements. These findings indicate that valbenazine can be a highly effective long-term treatment in patients with TD.


Asunto(s)
Discinesia Tardía , Tetrabenazina , Valina , Humanos , Tetrabenazina/análogos & derivados , Tetrabenazina/farmacología , Tetrabenazina/administración & dosificación , Tetrabenazina/efectos adversos , Discinesia Tardía/tratamiento farmacológico , Masculino , Femenino , Persona de Mediana Edad , Valina/análogos & derivados , Valina/administración & dosificación , Valina/farmacología , Valina/efectos adversos , Anciano , Resultado del Tratamiento , Adulto , Escala de Movimientos Involuntarios Anormales , Antipsicóticos/efectos adversos , Antipsicóticos/administración & dosificación
19.
J Clin Psychopharmacol ; 44(2): 107-116, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38421921

RESUMEN

PURPOSE: This post hoc analysis investigated whether a patient's underlying psychiatric disease (schizophrenia/schizoaffective disorder [SCHZ] or bipolar disorder/depressive disorder [MOOD]) influenced the efficacy or safety of valbenazine for tardive dyskinesia (TD) in an Asian population. METHODS: We analyzed data from J-KINECT, a multicenter, phase II/III, randomized, double-blind study, which consisted of a 6-week placebo-controlled period followed by a 42-week extension where Japanese patients with TD received once-daily 40- or 80-mg valbenazine. We compared the change from baseline in Abnormal Involuntary Movement Scale total score and Clinical Global Impression of TD score between patients with SCHZ and those with MOOD, and incidence of treatment-emergent adverse events. RESULTS: Of 256 patients included in the placebo-controlled period, 211 continued to the long-term extension. The mean change from baseline in Abnormal Involuntary Movement Scale total score at week 6 (95% confidence interval) was -1.8 (-3.2 to -0.5) and -3.3 (-4.7 to -1.9) in the valbenazine 40- and 80-mg groups, respectively (SCHZ group), and -2.4 (-3.9 to -0.9) and -3.5 (-5.1 to -1.9) in the valbenazine 40- and 80-mg groups, respectively (MOOD group), demonstrating improvement at either dose level over placebo, regardless of the underlying disease. These results were maintained to week 48, and improvements of Clinical Global Impression of TD scores were similar. There were no notable differences in the incidence of serious or fatal treatment-emergent adverse events by underlying disease; differences in the incidence of worsening schizophrenia and depression were attributed to underlying disease progression. CONCLUSIONS: Safety and efficacy of long-term valbenazine therapy for TD did not vary according to underlying psychiatric disease.


Asunto(s)
Antipsicóticos , Trastorno Bipolar , Trastorno Depresivo , Trastornos Psicóticos , Esquizofrenia , Discinesia Tardía , Tetrabenazina , Valina , Humanos , Antipsicóticos/efectos adversos , Trastorno Bipolar/inducido químicamente , Trastorno Depresivo/tratamiento farmacológico , Japón , Trastornos Psicóticos/tratamiento farmacológico , Esquizofrenia/tratamiento farmacológico , Esquizofrenia/complicaciones , Discinesia Tardía/inducido químicamente , Tetrabenazina/análogos & derivados , Valina/análogos & derivados
20.
Amino Acids ; 56(1): 2, 2024 Jan 27.
Artículo en Inglés | MEDLINE | ID: mdl-38285159

RESUMEN

By affecting the ovarian pool of follicles and their enclosed oocytes, heat stress has an impact on dairy cow fertility. This study aimed to determine how heat shock (HS) during in vitro maturation affected the ability of the bovine cumulus-oocyte complexes (COCs) to develop, as well as their metabolism of amino acids (AAs). In this study, COCs were in vitro matured for 23 h at 38.5 °C (control; n = 322), 39.5 °C (mild HS (MHS); n = 290), or 40.5 °C (severe HS (SHS); n = 245). In comparison to the control group, the MHS and SHS groups significantly decreased the percentage of metaphase-II oocytes, as well as cumulus cell expansion and viability. The SHS decreased the rates of cleavage and blastocyst formation in comparison to the control and MHS. Compared to the control and MHS-COCs, the SHS-COCs produced significantly more phenylalanine, threonine, valine, arginine, alanine, glutamic acid, and citrulline while depleting less leucine, glutamine, and serine. Data showed that SHS-COCs had the highest appearance and turnover of all AAs and essential AAs. Heat shock was positively correlated with the appearance of glutamic acid, glutamine, isoleucine, alanine, serine, valine, phenylalanine, and asparagine. Network analysis identified the relationship between HS and alanine or glutamic acid, as well as the relationship between blastocyst and cleavage rates and ornithine. The findings imply that SHS may have an impact on the quality and metabolism of AAs in COCs. Moreover, the use of a multistep analysis could simply identify the AAs most closely linked to HS and the developmental competence of bovine COCs.


Asunto(s)
Glutamina , Oocitos , Femenino , Bovinos , Animales , Ácido Glutámico , Alanina , Respuesta al Choque Térmico , Fenilalanina , Valina , Citrulina , Serina
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