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1.
mBio ; 15(5): e0056224, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38564667

RESUMEN

Spores of Bacillus subtilis germinate in response to specific germinant molecules that are recognized by receptors in the spore envelope. Germinants signal to the dormant spore that the environment can support vegetative growth, so many germinants, such as alanine and valine, are also essential metabolites. As such, they are also required to build the spore. Here we show that these germinants cause premature germination if they are still present at the latter stages of spore formation and beyond, but that B. subtilis metabolism is configured to prevent this: alanine and valine are catabolized and cleared from wild-type cultures even when alternative carbon and nitrogen sources are present. Alanine and valine accumulate in the spent media of mutants that are unable to catabolize these amino acids, and premature germination is pervasive. Premature germination does not occur if the germinant receptor that responds to alanine and valine is eliminated, or if wild-type strains that are able to catabolize and clear alanine and valine are also present in coculture. Our findings demonstrate that spore-forming bacteria must fine-tune the concentration of any metabolite that can also function as a germinant to a level that is high enough to allow for spore development to proceed, but not so high as to promote premature germination. These results indicate that germinant selection and metabolism are tightly linked, and suggest that germinant receptors evolve in tandem with the catabolic priorities of the spore-forming bacterium. IMPORTANCE: Many bacterial species produce dormant cells called endospores, which are not killed by antibiotics or common disinfection practices. Endospores pose critical challenges in the food industry, where endospore contaminations cause food spoilage, and in hospitals, where infections by pathogenic endospore formers threaten the life of millions every year. Endospores lose their resistance properties and can be killed easily when they germinate and exit dormancy. We have discovered that the enzymes that break down the amino acids alanine and valine are critical for the production of stable endospores. If these enzymes are absent, endospores germinate as they are formed or shortly thereafter in response to alanine, which can initiate the germination of many different species' endospores, or to valine. By blocking the activity of alanine dehydrogenase, the enzyme that breaks down alanine and is not present in mammals, it may be possible to inactivate endospores by triggering premature and unproductive germination.


Asunto(s)
Alanina , Aminoácidos , Bacillus subtilis , Esporas Bacterianas , Bacillus subtilis/metabolismo , Bacillus subtilis/genética , Bacillus subtilis/crecimiento & desarrollo , Esporas Bacterianas/metabolismo , Esporas Bacterianas/crecimiento & desarrollo , Esporas Bacterianas/genética , Alanina/metabolismo , Aminoácidos/metabolismo , Valina/metabolismo , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Medios de Cultivo/química
2.
Life Sci Alliance ; 7(6)2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38599770

RESUMEN

Translational regulation by non-coding RNAs is a mechanism commonly used by cells to fine-tune gene expression. A fragment derived from an archaeal valine tRNA (Val-tRF) has been previously identified to bind the small subunit of the ribosome and inhibit translation in Haloferax volcanii Here, we present three cryo-electron microscopy structures of Val-tRF bound to the small subunit of Sulfolobus acidocaldarius ribosomes at resolutions between 4.02 and 4.53 Å. Within these complexes, Val-tRF was observed to bind to conserved RNA-interacting sites, including the ribosomal decoding center. The binding of Val-tRF destabilizes helices h24, h44, and h45 and the anti-Shine-Dalgarno sequence of 16S rRNA. The binding position of this molecule partially overlaps with the translation initiation factor aIF1A and occludes the mRNA P-site codon. Moreover, we found that the binding of Val-tRF is associated with steric hindrance of the H69 base of 23S rRNA in the large ribosome subunit, thereby preventing 70S assembly. Our data exemplify how tRNA-derived fragments bind to ribosomes and provide new insights into the mechanisms underlying translation inhibition by Val-tRFs.


Asunto(s)
ARN de Transferencia , Ribosomas , ARN Ribosómico 16S/genética , ARN Ribosómico 16S/análisis , ARN Ribosómico 16S/metabolismo , Microscopía por Crioelectrón , Ribosomas/genética , ARN de Transferencia/genética , ARN de Transferencia/química , ARN de Transferencia/metabolismo , Valina/análisis , Valina/metabolismo
3.
Front Immunol ; 15: 1354128, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38558806

RESUMEN

Importance: Disease models for atopic dermatitis (AD) have primarily focused on understanding underlying environmental, immunologic, and genetic etiologies. However, the role of metabolic mechanisms in AD remains understudied. Objective: To investigate the circulating blood metabolomic and cytokine profile of AD as compared to healthy control patients. Design: This study collected plasma from 20 atopic dermatitis with moderate-to-severe itch (score of ≥5 on the itch Numeric Rating Scale and IGA score ≥3) and 24 healthy control patients. Mass-spectrometry based metabolite data were compared between AD and healthy controls. Unsupervised and supervised machine learning algorithms and univariate analysis analyzed metabolic concentrations. Metabolite enrichment and pathway analyses were performed on metabolites with significant fold change between AD and healthy control patients. To investigate the correlation between metabolites levels and cytokines, Spearman's rank correlation coefficients were calculated between metabolites and cytokines. Setting: Patients were recruited from the Johns Hopkins Itch Center and dermatology outpatient clinics in the Johns Hopkins Outpatient Center. Participants: The study included 20 atopic dermatitis patients and 24 healthy control patients. Main outcomes and measures: Fold changes of metabolites in AD vs healthy control plasma. Results: In patients with AD, amino acids isoleucine, tyrosine, threonine, tryptophan, valine, methionine, and phenylalanine, the amino acid derivatives creatinine, indole-3-acrylic acid, acetyl-L-carnitine, L-carnitine, 2-hydroxycinnamic acid, N-acetylaspartic acid, and the fatty amide oleamide had greater than 2-fold decrease (all P-values<0.0001) compared to healthy controls. Enriched metabolites were involved in branched-chain amino acid (valine, leucine, and isoleucine) degradation, catecholamine biosynthesis, thyroid hormone synthesis, threonine metabolism, and branched and long-chain fatty acid metabolism. Dysregulated metabolites in AD were positively correlated cytokines TARC and MCP-4 and negatively correlated with IL-1a and CCL20. Conclusions and relevance: Our study characterized novel dysregulated circulating plasma metabolites and metabolic pathways that may be involved in the pathogenesis of AD. These metabolic pathways serve as potential future biomarkers and therapeutic targets in the treatment of AD.


Asunto(s)
Dermatitis Atópica , Humanos , Citocinas/metabolismo , Isoleucina , Prurito , Valina , Treonina
4.
Spectrochim Acta A Mol Biomol Spectrosc ; 315: 124245, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38581722

RESUMEN

Simeprevir and daclatasvir represent a cornerstone in the management of Hepatitis C Virus infection, a global health concern that affects millions of people worldwide. In this study, we propose a synergistic approach combining synchronous spectrofluorimetry and chemometric modeling i.e. Partial Least Squares (PLS-1) for the analysis of simeprevir and daclatasvir in different matrices. Moreover, the study employs firefly algorithms to further optimize the chemometric models via selecting the most informative features thus improving the accuracy and robustness of the calibration models. The firefly algorithm was able to reduce the number of selected wavelengths to 47-44% for simeprevir and daclatasvir, respectively offering a fast and sensitive technique for the determination of simeprevir and daclatasvir. Validation results underscore the models' effectiveness, as evidenced by recovery rates close to 100% with relative root mean square error of prediction (RRMSEP) of 2.253 and 2.1381 for simeprevir and daclatasvir, respectively. Moreover, the proposed models have been applied to determine the pharmacokinetics of simeprevir and daclatasvir, providing valuable insights into their distribution and elimination patterns. Overall, the study demonstrates the effectiveness of synchronous spectrofluorimetry coupled with multivariate calibration optimized by firefly algorithms in accurately determining and quantifying simeprevir and daclatasvir in HCV antiviral treatment, offering potential applications in pharmaceutical formulation analysis and pharmacokinetic studies for these drugs.


Asunto(s)
Carbamatos , Imidazoles , Pirrolidinas , Simeprevir , Espectrometría de Fluorescencia , Valina , Valina/análogos & derivados , Imidazoles/farmacocinética , Imidazoles/química , Valina/farmacocinética , Simeprevir/farmacocinética , Simeprevir/análisis , Pirrolidinas/química , Carbamatos/farmacocinética , Análisis de los Mínimos Cuadrados , Espectrometría de Fluorescencia/métodos , Algoritmos , Antivirales/farmacocinética , Reproducibilidad de los Resultados
5.
Artículo en Inglés | MEDLINE | ID: mdl-38497033

RESUMEN

Background: Tardive Dyskinesia (TD) is a neurological disorder characterized by involuntary movements, often caused by dopamine receptor antagonists. Vesicular Monoamine Transporter 2 (VMAT2) inhibitors, such as valbenazine and deutetrabenazine, have emerged as promising therapies for TD and several clinical trials have shown their efficacy. This study aims to compare the efficacy and safety profile of VMAT2 inhibitors, focusing on a recent trial conducted in the Asian population. Methods: We reviewed the PubMed, Cochrane Library, Embase database, and clinicaltrials.gov between January 2017 and October 2023, using the keywords "tardive dyskinesia" AND ("valbenazine" [all fields] OR " deutetrabenazine " [all fields]) AND "clinical trial". The reviewed articles were studied for efficacy and side effects. Results: An initial search yielded 230 articles, of which 104 were duplicates. Following the title and abstract screening, 25 additional articles were excluded. A full-text review resulted in the exclusion of 96 more articles. Ultimately, four double-blind clinical trials met the inclusion criteria. The deutetrabenazine studies demonstrated significant improvements in Abnormal Involuntary Movement Scale (AIMS) scores compared to placebo, with no difference in adverse events. The valbenazine studies showed favorable results in reducing TD symptoms and were well-tolerated. Discussion: The studies reviewed in this analysis underscore the potential of deutetrabenazine and valbenazine as valuable treatment options for TD in diverse populations. Both medications demonstrated significant improvements in AIMS scores, suggesting their effectiveness in managing TD symptoms. Additionally, they exhibited favorable safety profiles, with low rates of serious adverse events and no significant increase in QT prolongation, parkinsonism, suicidal ideation, or mortality. Conclusion: The studies reviewed highlight the promising efficacy and tolerability of deutetrabenazine and valbenazine as treatments for Tardive Dyskinesia, providing new hope for individuals affected by this challenging condition.


Asunto(s)
Discinesia Tardía , Tetrabenazina , Valina , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Discinesia Tardía/tratamiento farmacológico , Discinesia Tardía/inducido químicamente , Tetrabenazina/efectos adversos , Tetrabenazina/análogos & derivados , Tetrabenazina/uso terapéutico , Valina/análogos & derivados , Proteínas de Transporte Vesicular de Monoaminas
6.
Int J Mol Sci ; 25(6)2024 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-38542117

RESUMEN

Rabson-Mendenhall syndrome (RMS) is a rare autosomal recessive disorder characterized by severe insulin resistance, resulting in early-onset diabetes mellitus. We report the first case of RMS in a Paraguayan patient. The patient is a 6-year-old girl who presented with hypertrichosis, acanthosis nigricans, nephrocalcinosis, and elevated levels of glucose and insulin that served as diagnostic indicators for RMS. Genetic testing by next-generation sequencing (NGS) revealed two pathogenic variants in exons 2 and 19 of the INSR gene: c.332G>T (p.Gly111Val) and c.3485C>T (p.Ala1162Val), in combined heterozygosis. The novel INSR c. 332G>T variant leads to the substitution of glycine to valine at position 111 in the protein, and multiple in silico software programs predicted it as pathogenic. The c.3485C>T variant leads to the substitution of alanine to valine at position 1162 in the protein previously described for insulin resistance and RMS. The management of RMS is particularly challenging in children, and the use of metformin is often limited by its side effects. The patient was managed with nutritional measures due to the early age of onset. This report expands the knowledge of RMS to the Paraguayan population and adds a novel pathogenic variant to the existing literature.


Asunto(s)
Síndrome de Donohue , Resistencia a la Insulina , Niño , Femenino , Humanos , Síndrome de Donohue/diagnóstico , Resistencia a la Insulina/genética , Receptor de Insulina/genética , Receptor de Insulina/metabolismo , Mutación , Valina/genética , Antígenos CD/genética
7.
EMBO Mol Med ; 16(4): 870-884, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38462666

RESUMEN

Recessive dystrophic epidermolysis bullosa (RDEB) is a rare inherited skin disease characterized by defects in type VII collagen leading to a range of fibrotic pathologies resulting from skin fragility, aberrant wound healing, and altered dermal fibroblast physiology. Using a novel in vitro model of fibrosis based on endogenously produced extracellular matrix, we screened an FDA-approved compound library and identified antivirals as a class of drug not previously associated with anti-fibrotic action. Preclinical validation of our lead hit, daclatasvir, in a mouse model of RDEB demonstrated significant improvement in fibrosis as well as overall quality of life with increased survival, weight gain and activity, and a decrease in pruritus-induced hair loss. Immunohistochemical assessment of daclatasvir-treated RDEB mouse skin showed a reduction in fibrotic markers, which was supported by in vitro data demonstrating TGFß pathway targeting and a reduction of total collagen retained in the extracellular matrix. Our data support the clinical development of antivirals for the treatment of patients with RDEB and potentially other fibrotic diseases.


Asunto(s)
Carbamatos , Epidermólisis Ampollosa Distrófica , Imidazoles , Pirrolidinas , Valina/análogos & derivados , Humanos , Animales , Ratones , Epidermólisis Ampollosa Distrófica/tratamiento farmacológico , Epidermólisis Ampollosa Distrófica/patología , Calidad de Vida , Colágeno Tipo VII/metabolismo , Colágeno Tipo VII/uso terapéutico , Fibrosis , Antivirales/farmacología , Antivirales/uso terapéutico , Piel/metabolismo , Piel/patología
8.
Bioresour Technol ; 398: 130538, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38452952

RESUMEN

Advancement in commodity chemical production from carbon dioxide (CO2) offers a promising path towards sustainable development goal. Cupriavidus necator is an ideal host to convert CO2 into high-value chemicals, thereby achieving this target. Here, C. necator was engineered for heterotrophic and autotrophic production of L-isoleucine and L-valine. Citramalate synthase was introduced to simplify isoleucine synthesis pathway. Blocking poly-hydroxybutyrate biosynthesis resulted in significant accumulation of isoleucine and valine. Besides, strategies like key enzymes screening and overexpressing, reducing power balancing and feedback inhibition removing were applied in strain modification. Finally, the maximum isoleucine and valine titers of the best isoleucine-producing and valine-producing strains reached 857 and 972 mg/L, respectively, in fed-batch fermentation using glucose as substrate, and 105 and 319 mg/L, respectively, in autotrophic fermentation using CO2 as substrate. This study provides a feasible solution for developing C. necator as a microbial factory to produce amino acids from CO2.


Asunto(s)
Dióxido de Carbono , Cupriavidus necator , Dióxido de Carbono/metabolismo , Isoleucina , Cupriavidus necator/genética , Valina , Procesos Autotróficos
9.
Ecotoxicol Environ Saf ; 275: 116230, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38552389

RESUMEN

Epidemiological evidence on the health effects of pesticide exposure among greenhouse workers is limited, and the mechanisms are lacking. Building upon our team's previous population study, we selected two pesticides, CPF and EB, with high detection rates, based on the theoretical foundation that the liver serves as a detoxifying organ, we constructed a toxicity model using HepG2 cells to investigate the impact of individual or combined pesticide exposure on the hepatic metabolism profile, attempting to identify targeted biomarkers. Our results showed that CPF and EB could significantly affect the survival rate of HepG2 cells and disrupt their metabolic profile. There were 117 metabolites interfered by CPF exposure, which mainly affected ABC transporter, biosynthesis of amino acids, center carbon metabolism in cancer, fatty acid biosynthesis and other pathways, 95 metabolites interfered by EB exposure, which mainly affected center carbon metabolism in cancer, HIF-1 signaling pathway, valine, leucine and isoleucine biosynthesis, fatty acid biosynthesis and other pathways. The cross analysis and further biological experiments confirmed that CPF and EB pesticide exposure may affect the HIF-1 signaling pathway and valine, leucine and isoleucine biosynthesis in HepG2 cells, providing reliable experimental evidence for the prevention and treatment of liver damage in greenhouse workers.


Asunto(s)
Cloropirifos , Insecticidas , Ivermectina/análogos & derivados , Plaguicidas , Humanos , Cloropirifos/toxicidad , Cloropirifos/metabolismo , Plaguicidas/toxicidad , Células Hep G2 , Leucina , Isoleucina , Carbono , Valina , Ácidos Grasos , Insecticidas/toxicidad , Insecticidas/metabolismo
10.
Fish Shellfish Immunol ; 148: 109494, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38499217

RESUMEN

Vibrio harveyi poses a significant threat to fish and invertebrates in mariculture, resulting in substantial financial repercussions for the aquaculture sector. Valine-glycine repeat protein G (VgrG) is essential for the type VI secretion system's (T6SS) assembly and secretion. VgrG from V. harveyi QT520 was cloned and analyzed in this study. The localization of VgrG was determined by Western blot, which revealed that it was located in the cytoplasm, secreted extracellularly, and attached to the membrane. The effectiveness of two vaccinations against V. harveyi infection-a subunit vaccine (rVgrG) and a DNA vaccine (pCNVgrG) prepared with VgrG was evaluated. The findings indicated that both vaccines provided a degree of protection against V. harveyi challenge. At 4 weeks post-vaccination (p.v.), the rVgrG and pCNVgrG exhibited relative percent survival rates (RPS) of 71.43% and 76.19%, respectively. At 8 weeks p.v., the RPS for rVgrG and pCNVgrG were 68.21% and 72.71%, respectively. While both rVgrG and pCNVgrG elicited serum antibody production, the subunit vaccinated fish demonstrated significantly higher levels of serum anti-VgrG specific antibodies than the DNA vaccine group. The result of qRT-PCR demonstrated that the expression of major histocompatibility complex (MHC) class Iα, tumor necrosis factor-alpha (TNF-α), interferon γ (IFNγ), and cluster of differentiation 4 (CD4) were up-regulated by both rVgrG and pCNVgrG. Fish vaccinated with rVgrG and pCNVgrG exhibited increased activity of acid phosphatase, alkaline phosphatase, superoxide dismutase, and lysozyme. These findings suggest that VgrG from V. harveyi holds potential for application in vaccination.


Asunto(s)
Enfermedades de los Peces , Vacunas de ADN , Vibriosis , Vibrio , Animales , Vibriosis/prevención & control , Vibriosis/veterinaria , Valina , Vacunas Bacterianas , Peces , Enfermedades de los Peces/prevención & control
11.
Drugs ; 84(3): 355-361, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38409573

RESUMEN

Nirogacestat (OGSIVEO™) is an oral, selective, reversible, small molecule γ-secretase inhibitor developed by SpringWorks Therapeutics, Inc. γ-Secretase is a multi-subunit protease complex that cleaves multiple transmembrane protein complexes, including Notch and membrane-bound B-cell maturation antigen (BCMA). Inhibition of γ-secretase may result in growth inhibition of tumour cells overexpressing Notch, and preservation of membrane-bound BCMA may increase target density for BCMA-targeted therapy. In November 2023, nirogacestat was approved in the USA for use in adult patients with progressing desmoid tumours who require systemic treatment. This article summarizes the milestones in the development of nirogacestat leading to this first approval for the systemic treatment of desmoid tumours.


Asunto(s)
Secretasas de la Proteína Precursora del Amiloide , Fibromatosis Agresiva , Valina/análogos & derivados , Humanos , Secretasas de la Proteína Precursora del Amiloide/metabolismo , Antígeno de Maduración de Linfocitos B/metabolismo , Tetrahidronaftalenos
12.
Hipertens Riesgo Vasc ; 41(1): 17-25, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38418298

RESUMEN

INTRODUCTION: "Amlodipine/valsartan" or "amlodipine/candesartan" combinations represent two effective antihypertensive agents with complementary mechanisms of action. Nevertheless, a study has yet to be done to evaluate the effect of amlodipine/candesartan on central blood pressure and compare it with amlodipine/valsartan combination. To see how "amlodipine plus candesartan combination" reduces peripheral and central blood pressure compared to the most studied combination, "amlodipine plus valsartan". MATERIAL AND METHODS: Eighty-six patients were randomized in an open-label, prospective study by 1:1 ratio to two groups. Group I (n=42) received the amlodipine and valsartan combination, and group II (n=44) received the amlodipine and candesartan combination. Peripheral and central blood pressure (CBP) was measured at baseline, at 6 and 12 weeks of follow-up. DISCUSSION: Both treatment groups reduced peripheral systolic, diastolic, and mean blood pressure. There was no significant difference between and within both groups. The amlodipine/candesartan combination showed more reduction in peripheral systolic blood pressure (PSBP) after 12 weeks of treatment (p=<0.001). Both groups decreased CBP without significant differences between groups. The amlodipine/candesartan combination showed additional efficacy in decreasing CSBP after 12 weeks (p=<0.001). The two treatment groups did not exert significant efficacy in lowering heart rate (HR) and augmentation index% (AIx%). CONCLUSION: To conclude, the amlodipine 10mg/candesartan 16mg combination was non-inferior to the amlodipine 10mg/valsartan 160mg combination in terms of reducing peripheral and CBP over time.


Asunto(s)
Amlodipino , Bencimidazoles , Compuestos de Bifenilo , Hipertensión , Humanos , Amlodipino/efectos adversos , Valsartán/farmacología , Valsartán/uso terapéutico , Presión Sanguínea , Hipertensión/tratamiento farmacológico , Estudios Prospectivos , Valina/farmacología , Valina/uso terapéutico , Antihipertensivos/efectos adversos , Tetrazoles/efectos adversos , Quimioterapia Combinada
13.
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
14.
J Am Chem Soc ; 146(8): 5550-5559, 2024 Feb 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
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.
Antiviral Res ; 224: 105842, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38417531

RESUMEN

Enteroviruses are a significant global health concern, causing a spectrum of diseases from the common cold to more severe conditions like hand-foot-and-mouth disease, meningitis, myocarditis, pancreatitis, and poliomyelitis. Current treatment options for these infections are limited, underscoring the urgent need for effective therapeutic strategies. To find better treatment option we analyzed toxicity and efficacy of 12 known broad-spectrum anti-enterovirals both individually and in combinations against different enteroviruses in vitro. We identified several novel, synergistic two-drug and three-drug combinations that demonstrated significant inhibition of enterovirus infections in vitro. Specifically, the triple-drug combination of pleconaril, rupintrivir, and remdesivir exhibited remarkable efficacy against echovirus (EV) 1, EV6, EV11, and coxsackievirus (CV) B5, in human lung epithelial A549 cells. This combination surpassed the effectiveness of single-agent or dual-drug treatments, as evidenced by its ability to protect A549 cells from EV1-induced cytotoxicity across seven passages. Additionally, this triple-drug cocktail showed potent antiviral activity against EV-A71 in human intestinal organoids. Thus, our findings highlight the therapeutic potential of the pleconaril-rupintrivir-remdesivir combination as a broad-spectrum treatment option against a range of enterovirus infections. The study also paves the way towards development of strategic antiviral drug combinations with virus family coverage and high-resistance barriers.


Asunto(s)
Adenosina Monofosfato/análogos & derivados , Alanina/análogos & derivados , Enterovirus Humano A , Infecciones por Enterovirus , Enterovirus , Isoxazoles , Oxadiazoles , Oxazoles , Fenilalanina/análogos & derivados , Pirrolidinonas , Valina/análogos & derivados , Animales , Humanos , Infecciones por Enterovirus/tratamiento farmacológico , Enterovirus Humano B , Antivirales/farmacología , Antivirales/uso terapéutico , Combinación de Medicamentos
17.
J Am Heart Assoc ; 13(5): e032084, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38420789

RESUMEN

BACKGROUND: This study aimed to investigate the causal relationships between branched-chain amino acids (BCAAs) and the risks of hypertension via meta-analysis and Mendelian randomization analysis. METHODS AND RESULTS: A meta-analysis of 32 845 subjects was conducted to evaluate the relationships between BCAAs and hypertension. In Mendelian randomization analysis, independent single-nucleotide polymorphisms associated with BCAAs at the genome-wide significance level were selected as the instrumental variables. Meanwhile, the summary-level data for essential hypertension and secondary hypertension end points were obtained from the FinnGen study. As suggested by the meta-analysis results, elevated BCAA levels were associated with a higher risk of hypertension (isoleucine: summary odds ratio, 1.26 [95% CI, 1.08-1.47]; leucine: summary odds ratio, 1.28 [95% CI, 1.07-1.52]; valine: summary odds ratio, 1.32 [95% CI, 1.12-1.57]). Moreover, the inverse variance-weighted method demonstrated that an elevated circulating isoleucine level might be the causal risk factor for essential hypertension but not secondary hypertension (essential hypertension: odds ratio, 1.22 [95% CI, 1.12-1.34]; secondary hypertension: odds ratio, 0.96 [95% CI, 0.54-1.68]). CONCLUSIONS: The increased levels of 3 BCAAs positively correlated with an increased risk of hypertension. Particularly, elevated isoleucine level is a causal risk factor for essential hypertension. Increased levels of leucine and valine also tend to increase the risk of essential hypertension, but further verification is still warranted.


Asunto(s)
Aminoácidos de Cadena Ramificada , Hipertensión , Humanos , Aminoácidos de Cadena Ramificada/metabolismo , Isoleucina/genética , Leucina , Análisis de la Aleatorización Mendeliana , Valina , Hipertensión/epidemiología , Hipertensión/genética , Hipertensión/inducido químicamente , Hipertensión Esencial , Estudio de Asociación del Genoma Completo
18.
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
19.
Bioresour Technol ; 397: 130502, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38417463

RESUMEN

Branched-chain amino acids (BCAAs) such as L-valine, L-leucine, and L-isoleucine are widely used in food and feed. To comply with sustainable development goals, commercial production of BCAAs has been completely replaced with microbial fermentation. However, the efficient production of BCAAs by microorganisms remains a serious challenge due to their staggered metabolic networks and cell growth. To overcome these difficulties, systemic metabolic engineering has emerged as an effective and feasible strategy for the biosynthesis of BCAA. This review firstly summarizes the research advances in the microbial synthesis of BCAAs and representative engineering strategies. Second, systematic methods, such as high-throughput screening, adaptive laboratory evolution, and omics analysis, can be used to analyses the synthesis of BCAAs at the whole-cell level and further improve the titer of target chemicals. Finally, new tools and engineering strategies that may increase the production output and development direction of the microbial production of BCAAs are discussed.


Asunto(s)
Aminoácidos de Cadena Ramificada , Isoleucina , Aminoácidos de Cadena Ramificada/metabolismo , Leucina/metabolismo , Valina , Ingeniería Metabólica
20.
ACS Biomater Sci Eng ; 10(3): 1393-1402, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38386412

RESUMEN

Pseudopeptide-based bioinspired materials are emerging for selective recognition of biologically significant analytes and are applicable in the modern nanoscience field. Therefore, we have developed novel multifunctional C2-symmetric soft pseudopeptides by amino acid l-valine and salicylaldehyde fragments using a series of aliphatic linkers. They are highly selective and sensitive to Zn (II) ions under physiological conditions and reveal significant fluorescence enhancement with the PET mechanism. The molecular self-assembly shows zinc-induced morphological transformation of the rod-shaped assembly into a chain-like morphology. Such a metal-induced hierarchical nano-assembly may have relevance for specific nanobiotechnology applications.


Asunto(s)
Valina , Zinc , Iones
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