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3.
Sci Rep ; 14(1): 8695, 2024 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622194

RESUMO

AMPylation is a biologically significant yet understudied post-translational modification where an adenosine monophosphate (AMP) group is added to Tyrosine and Threonine residues primarily. While recent work has illuminated the prevalence and functional impacts of AMPylation, experimental identification of AMPylation sites remains challenging. Computational prediction techniques provide a faster alternative approach. The predictive performance of machine learning models is highly dependent on the features used to represent the raw amino acid sequences. In this work, we introduce a novel feature extraction pipeline to encode the key properties relevant to AMPylation site prediction. We utilize a recently published dataset of curated AMPylation sites to develop our feature generation framework. We demonstrate the utility of our extracted features by training various machine learning classifiers, on various numerical representations of the raw sequences extracted with the help of our framework. Tenfold cross-validation is used to evaluate the model's capability to distinguish between AMPylated and non-AMPylated sites. The top-performing set of features extracted achieved MCC score of 0.58, Accuracy of 0.8, AUC-ROC of 0.85 and F1 score of 0.73. Further, we elucidate the behaviour of the model on the set of features consisting of monogram and bigram counts for various representations using SHapley Additive exPlanations.


Assuntos
Processamento de Proteína Pós-Traducional , Tirosina , Tirosina/metabolismo , Sequência de Aminoácidos , Monofosfato de Adenosina/metabolismo , Treonina/metabolismo
4.
Sci Rep ; 14(1): 9303, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38654033

RESUMO

Remdesivir (RDV) was the first Food and Drug Administration (FDA)-approved medication for COVID-19, with discordant data on efficacy in reducing mortality risk and disease progression. In the context of a dynamic and rapidly changing pandemic landscape, the utilization of real-world evidence is of utmost importance. The objective of this study is to evaluate the impact of RDV on patients who have been admitted to two university referral hospitals in Italy due to COVID-19. All patients older than 18 years and hospitalized at two different universities (Bari and Palermo) were enrolled in this study. To minimize the effect of potential confounders, we used propensity score matching with one case (Remdesivir) and one control that never experienced this kind of intervention during hospitalization. Mortality was the primary outcome of our investigation, and it was recorded using death certificates and/or medical records. Severe COVID-19 was defined as admission to the intensive care unit or a qSOFAscore ≥ 2 or CURB65scores ≥ 3. After using propensity score matching, 365 patients taking Remdesivir and 365 controls were included. No significant differences emerged between the two groups in terms of mean age and percentage of females, while patients taking Remdesivir were less frequently active smokers (p < 0.0001). Moreover, the patients taking Remdesivir were less frequently vaccinated against COVID-19. All the other clinical, radiological, and pharmacological parameters were balanced between the two groups. The use of Remdesivir in our cohort was associated with a significantly lower risk of mortality during the follow-up period (HR 0.56; 95% CI 0.37-0.86; p = 0.007). Moreover, RDV was associated with a significantly lower incidence of non-invasive ventilation (OR 0.27; 95% CI 0.20-0.36). Furthermore, in the 365 patients taking Remdesivir, we observed two cases of mild renal failure requiring a reduction in the dosage of Remdesivir and two cases in which the physicians decided to interrupt Remdesivir for bradycardia and for QT elongation. Our study suggests that the use of Remdesivir in hospitalized COVID-19 patients is a safe therapy associated with improved clinical outcomes, including halving of mortality and with a reduction of around 75% of the risk of invasive ventilation. In a constantly changing COVID-19 scenario, ongoing research is necessary to tailor treatment decisions based on the latest scientific evidence and optimize patient outcomes.


Assuntos
Monofosfato de Adenosina , Monofosfato de Adenosina/análogos & derivados , Alanina , Alanina/análogos & derivados , Antivirais , Tratamento Farmacológico da COVID-19 , COVID-19 , Pontuação de Propensão , Humanos , Alanina/uso terapêutico , Monofosfato de Adenosina/uso terapêutico , Feminino , Masculino , Itália/epidemiologia , Pessoa de Meia-Idade , Idoso , Antivirais/uso terapêutico , COVID-19/mortalidade , COVID-19/epidemiologia , Hospitalização/estatística & dados numéricos , SARS-CoV-2 , Resultado do Tratamento , Idoso de 80 Anos ou mais , Adulto , Estudos Retrospectivos
5.
Biochem J ; 481(8): 587-599, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38592738

RESUMO

The AMP-activated protein kinase (AMPK) is a sensor of cellular energy status. When activated by increases in ADP:ATP and/or AMP:ATP ratios (signalling energy deficit), AMPK acts to restore energy balance. Binding of AMP to one or more of three CBS repeats (CBS1, CBS3, CBS4) on the AMPK-γ subunit activates the kinase complex by three complementary mechanisms: (i) promoting α-subunit Thr172 phosphorylation by the upstream kinase LKB1; (ii) protecting against Thr172 dephosphorylation; (iii) allosteric activation. Surprisingly, binding of ADP has been reported to mimic the first two effects, but not the third. We now show that at physiologically relevant concentrations of Mg.ATP2- (above those used in the standard assay) ADP binding does cause allosteric activation. However, ADP causes only a modest activation because (unlike AMP), at concentrations just above those where activation becomes evident, ADP starts to cause competitive inhibition at the catalytic site. Our results cast doubt on the physiological relevance of the effects of ADP and suggest that AMP is the primary activator in vivo. We have also made mutations to hydrophobic residues involved in binding adenine nucleotides at each of the three γ subunit CBS repeats of the human α2ß2γ1 complex and examined their effects on regulation by AMP and ADP. Mutation of the CBS3 site has the largest effects on all three mechanisms of AMP activation, especially at lower ATP concentrations, while mutation of CBS4 reduces the sensitivity to AMP. All three sites appear to be required for allosteric activation by ADP.


Assuntos
Proteínas Quinases Ativadas por AMP , Difosfato de Adenosina , Monofosfato de Adenosina , Difosfato de Adenosina/metabolismo , Monofosfato de Adenosina/metabolismo , Humanos , Regulação Alostérica , Proteínas Quinases Ativadas por AMP/metabolismo , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/química , Ligantes , Fosforilação , Trifosfato de Adenosina/metabolismo , Ativação Enzimática , Ligação Proteica
6.
Front Immunol ; 15: 1328306, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38590528

RESUMO

CD39 is the major enzyme controlling the levels of extracellular adenosine triphosphate (ATP) via the stepwise hydrolysis of ATP to adenosine diphosphate (ADP) and adenosine monophosphate (AMP). As extracellular ATP is a strong promoter of inflammation, monoclonal antibodies (mAbs) blocking CD39 are utilized therapeutically in the field of immune-oncology. Though anti-CD39 mAbs are highly specific for their target, they lack deep penetration into the dense tissue of solid tumors, due to their large size. To overcome this limitation, we generated and characterized nanobodies that targeted and blocked human CD39. From cDNA-immunized alpacas we selected 16 clones from seven nanobody families that bind to two distinct epitopes of human CD39. Among these, clone SB24 inhibited the enzymatic activity of CD39. Of note, SB24 blocked ATP degradation by both soluble and cell surface CD39 as a 15kD monomeric nanobody. Dimerization via fusion to an immunoglobulin Fc portion further increased the blocking potency of SB24 on CD39-transfected HEK cells. Finally, we confirmed the CD39 blocking properties of SB24 on human PBMCs. In summary, SB24 provides a new small biological antagonist of human CD39 with potential application in cancer therapy.


Assuntos
Anticorpos de Domínio Único , Humanos , Anticorpos de Domínio Único/farmacologia , Trifosfato de Adenosina/metabolismo , Monofosfato de Adenosina , Difosfato de Adenosina/metabolismo
7.
Sci Rep ; 14(1): 5430, 2024 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-38443438

RESUMO

Studies conducted prior to SARS-CoV-2 Omicron demonstrated that sotrovimab and remdesivir reduced hospitalization among high-risk outpatients with mild to moderate COVID-19. However, their effectiveness has not been directly compared. This study examined all high-risk outpatients with mild to moderate COVID-19 who received either remdesivir or sotrovimab at Mayo Clinic during the Omicron BA.1 surge from January to March 2022. COVID-19-related hospitalization or death within 28 days were compared between the two treatment groups. Among 3257 patients, 2158 received sotrovimab and 1099 received remdesivir. Patients treated with sotrovimab were younger and had lower comorbidity but were more likely to be immunocompromised than remdesivir-treated patients. The majority (89%) had received at least one dose of COVID-19 vaccine. COVID-19-related hospitalization (1.5% and 1.0% in remdesivir and sotrovimab, respectively, p = .15) and mortality within 28 days (0.4% in both groups, p = .82) were similarly low. A propensity score weighted analysis demonstrated no significant difference in the outcomes between the two groups. We demonstrated favorable outcomes that were not significantly different between patients treated with remdesivir or sotrovimab.


Assuntos
Monofosfato de Adenosina/análogos & derivados , Alanina/análogos & derivados , Anticorpos Monoclonais Humanizados , Anticorpos Neutralizantes , COVID-19 , Pacientes Ambulatoriais , Humanos , Vacinas contra COVID-19 , SARS-CoV-2 , Tratamento Farmacológico da COVID-19
8.
Spectrochim Acta A Mol Biomol Spectrosc ; 313: 124114, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38447441

RESUMO

A ratiometric luminescent probe was fabricated using adenosine monophosphate (AMP) as a bridging ligand and 3-carboxyphenylboronic acid (3-CPBA) as the sensitizer and functional ligand that allowed the probe to recognize hydrogen peroxide (H2O2). The probe was labeled AMP-Tb/3-CPBA. Adding H2O2 caused the nonluminescent 3-CPBA to be converted into 3-hydroxybenzoic acid, which strongly luminesces at 401 nm. This meant that adding H2O2 decreased the AMP-Tb/3-CPBA luminescence intensity at 544 nm and caused luminescence at 401 nm. The 401 and 544 nm luminescence intensity ratio (I401/I544) was strongly associated with the H2O2 concentration between 0.1 and 60.0 µM, and the detection limit was 0.23 µM. Dual emission reverse-change ratio luminescence sensing using the probe allowed environmental effects to be excluded and the assay to be very selective. We believe that the results pave the way for the development of new functionalized lanthanide coordination polymers for use in luminescence assays.


Assuntos
Polímeros , Térbio , Peróxido de Hidrogênio , Luminescência , Ligantes , Monofosfato de Adenosina
9.
J Psychopharmacol ; 38(4): 395-403, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38481078

RESUMO

BACKGROUND: Due to non-consistent reports in the literature, there are uncertainties about the potential benefits and harms of selective serotonin reuptake inhibitors (SSRIs) in patients with Coronavirus disease 2019 (COVID-19). AIM: To investigate associations of SSRIs with clinical characteristics and unwanted outcomes among real-life severe and critical COVID-19 patients and their relationship with remdesivir (RDV) use. METHODS: This retrospective cohort study evaluated a total of 1558 COVID-19 patients of the white race treated in a tertiary center institution, among them 779 patients treated with RDV and 779 1:1 case-matched patients. RESULTS: A total of 78 (5%) patients were exposed to SSRIs during hospitalization, similarly distributed among patients treated with RDV and matched patients (5.1 and 4.9%). No significant associations of SSRI use with age, sex, comorbidity burden, and COVID-19 severity were present in either of the two cohorts (p > 0.05 for all analyses). In multivariate analyses adjusted for clinically meaningful variables, SSRI use was significantly associated with higher mortality among RDV (adjusted odds ratio (aOR) 2.0, p = 0.049) and matched patients (aOR 2.22, p = 0.044) and with higher risk for mechanical-ventilation (aOR 2.57, p = 0.006), venous-thromboembolism (aOR 3.69, p = 0.007), and bacteremia (aOR 2.22, p = 0.049) among RDV treated patients. CONCLUSIONS: Adverse outcomes associated with SSRI use in COVID-19 patients might be potentiated by RDV use, and clinically significant interactions between these two drug classes might exist. Although our findings raise important considerations for clinical practice, they are limited by retrospective nature of the study, lack of ethnic diversity, and the potential for unmeasured confounding factors. Future studies exploring underlying biological mechanisms are needed.


Assuntos
Monofosfato de Adenosina/análogos & derivados , Alanina/análogos & derivados , COVID-19 , Inibidores Seletivos de Recaptação de Serotonina , Humanos , Inibidores Seletivos de Recaptação de Serotonina/efeitos adversos , Estudos Retrospectivos , Tratamento Farmacológico da COVID-19
10.
Int J Biol Macromol ; 265(Pt 1): 130703, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38458279

RESUMO

Marine fungal exopolysaccharides play a crucial role in immunoregulation. In this investigation, a novel polysaccharide was extracted from the culture medium of the marine fungus Aspergillus medius SCAU-236. Compositional analysis revealed a structure composed of glucose units with (1,4)-α-D-Glcp, (1,3,4)-ß-D-Glcp, and (1,4,6)-α-D-Glcp, along with side chains of 1-α-D-Glcp linked to carbon 6 of (1,4,6)-α-D-Glcp and carbon 3 of (1,3,4)-ß-D-Glcp. Functional evaluations on RAW264.7 macrophage cells demonstrated Aspergillus medius polysaccharide (ASMP)'s effects on cell proliferation, nitric oxide levels, and the secretion of TNF-α, IL-6, and IL-1ß cytokines. Additionally, metabolomics indicated ASMP's potential to modulate macrophage immune function by impacting key regulatory molecules, including COX-2, iNOS, Nrf2, SLC7A11, GPX4, and ACSL4. The Nrf2/SLC7A11/GPX4 axis and ACSL4 were suggested to be involved in ASMP-induced ferroptosis, leading to increased reactive oxygen species (ROS) levels and lipid peroxidation. These findings propose a unique mechanism by which ASMP exerts immunomodulatory effects through ferroptosis induction, contributing to the understanding of marine-derived compounds in immunomodulation research.


Assuntos
Monofosfato de Adenosina/análogos & derivados , Ferroptose , Fator 2 Relacionado a NF-E2 , Tionucleotídeos , Animais , Camundongos , Aspergillus/química , Polissacarídeos/química , Células RAW 264.7 , Imunidade , Imunomodulação , Carbono
11.
Artigo em Inglês | MEDLINE | ID: mdl-38452850

RESUMO

Declining flesh quality has drawn considerable attention in the farmed large yellow croaker (LYC; Larimichthys crocea) industry. Inosine monophosphate (IMP) is the primary flavor substance in aquatic animals. Adenosine monophosphate deaminase 1 (AMPD1) plays a critical role in IMP formation by catalyzing the deamination of AMP to IMP in the purine nucleotide cycle. To further evaluate the correlation between ampd1 mRNA expression levels and IMP content in the LYC muscle tissue, the relevant open reading frame (ORF) of L. crocea (Lcampd1) was cloned, and the IMP content and Lcampd1 mRNA expression in the muscles of LYCs of different sizes were examined. The ORF cDNA of Lcampd1 was 2211 bp in length and encoded a polypeptide of 736 amino acids (AAs). The deduced protein, LcAMPD1, possesses conserved AMPD active regions (SLSTDDP) and shows high homology with AMPD proteins of other teleost fishes. The genomic DNA sequence of Lcampd1 exhibits a high degree of evolutionary conservation in terms of structural organization among species. Phylogenetic analysis of the deduced AA sequence revealed that teleost fish and mammalian AMPD1 were separate from each other and formed a cluster with AMPD3, suggesting that AMPD1 and AMPD3 arose by duplication of a common primordial gene. In healthy LYC, Lcampd1 mRNA was expressed only in the muscle tissue. The IMP content in the muscle of LYCs with different average body weights was measured by high-performance liquid chromatography; the results showed that the IMP content in the muscle of LYCs with greater body weight was significantly higher than that in LYC with lower body weight. Moreover, a similar trend in Lcampd1 expression was observed in these muscle tissues. The Pearson correlation analysis further showed that the Lcampd1 mRNA expression was positively correlated with IMP content in the muscles of different-sized LYCs. These results suggest the potential function of Lcampd1 in determining the IMP content in LYC and provide a theoretical basis for flesh quality improvement, as well as a scientific basis for the development of the molecular breeding of LYC.


Assuntos
Inosina Monofosfato , Perciformes , Animais , Sequência de Bases , Sequência de Aminoácidos , Inosina Monofosfato/metabolismo , Filogenia , Perciformes/genética , Perciformes/metabolismo , Monofosfato de Adenosina/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Peso Corporal/genética , Proteínas de Peixes/metabolismo , Mamíferos/metabolismo
12.
Antimicrob Agents Chemother ; 68(4): e0095623, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38446062

RESUMO

Viral RNA-dependent RNA polymerase (RdRp), a highly conserved molecule in RNA viruses, has recently emerged as a promising drug target for broad-acting inhibitors. Through a Vero E6-based anti-cytopathic effect assay, we found that BPR3P0128, which incorporates a quinoline core similar to hydroxychloroquine, outperformed the adenosine analog remdesivir in inhibiting RdRp activity (EC50 = 0.66 µM and 3 µM, respectively). BPR3P0128 demonstrated broad-spectrum activity against various severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants of concern. When introduced after viral adsorption, BPR3P0128 significantly decreased SARS-CoV-2 replication; however, it did not affect the early entry stage, as evidenced by a time-of-drug-addition assay. This suggests that BPR3P0128's primary action takes place during viral replication. We also found that BPR3P0128 effectively reduced the expression of proinflammatory cytokines in human lung epithelial Calu-3 cells infected with SARS-CoV-2. Molecular docking analysis showed that BPR3P0128 targets the RdRp channel, inhibiting substrate entry, which implies it operates differently-but complementary-with remdesivir. Utilizing an optimized cell-based minigenome RdRp reporter assay, we confirmed that BPR3P0128 exhibited potent inhibitory activity. However, an enzyme-based RdRp assay employing purified recombinant nsp12/nsp7/nsp8 failed to corroborate this inhibitory activity. This suggests that BPR3P0128 may inhibit activity by targeting host-related RdRp-associated factors. Moreover, we discovered that a combination of BPR3P0128 and remdesivir had a synergistic effect-a result likely due to both drugs interacting with separate domains of the RdRp. This novel synergy between the two drugs reinforces the potential clinical value of the BPR3P0128-remdesivir combination in combating various SARS-CoV-2 variants of concern.


Assuntos
Monofosfato de Adenosina/análogos & derivados , Alanina/análogos & derivados , COVID-19 , Pirazóis , Quinolinas , Humanos , SARS-CoV-2/metabolismo , RNA Polimerase Dependente de RNA/metabolismo , Simulação de Acoplamento Molecular , Tratamento Farmacológico da COVID-19 , Antivirais/química
13.
Science ; 383(6688): eadk6176, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38484056

RESUMO

Obeldesivir (ODV, GS-5245) is an orally administered prodrug of the parent nucleoside of remdesivir (RDV) and is presently in phase 3 trials for COVID-19 treatment. In this work, we show that ODV and its circulating parent nucleoside metabolite, GS-441524, have similar in vitro antiviral activity against filoviruses, including Marburg virus, Ebola virus, and Sudan virus (SUDV). We also report that once-daily oral ODV treatment of cynomolgus monkeys for 10 days beginning 24 hours after SUDV exposure confers 100% protection against lethal infection. Transcriptomics data show that ODV treatment delayed the onset of inflammation and correlated with antigen presentation and lymphocyte activation. Our results offer promise for the further development of ODV to control outbreaks of filovirus disease more rapidly.


Assuntos
Alanina , Antivirais , Ebolavirus , Doença pelo Vírus Ebola , Nucleosídeos , Pró-Fármacos , Animais , Administração Oral , Ebolavirus/efeitos dos fármacos , Doença pelo Vírus Ebola/tratamento farmacológico , Doença pelo Vírus Ebola/prevenção & controle , Macaca fascicularis , Nucleosídeos/administração & dosagem , Nucleosídeos/farmacologia , Monofosfato de Adenosina/administração & dosagem , Monofosfato de Adenosina/farmacologia , Alanina/administração & dosagem , Alanina/análogos & derivados , Alanina/farmacologia , Pró-Fármacos/administração & dosagem , Pró-Fármacos/farmacologia , Antivirais/administração & dosagem , Antivirais/farmacologia
14.
Clin Appl Thromb Hemost ; 30: 10760296241237228, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38439661

RESUMO

Cangrelor is a rapid-acting, intravenous P2Y12 inhibitor that can be used in patients after percutaneous coronary intervention who require mechanical circulatory support or as a bridge to procedure. We retrospectively reviewed adult patients who received platelet function testing (PFT) with the VerifyNow P2Y12 assay while on cangrelor from March 2021 through November 2022. All patients were initiated on 0.75 mcg/kg/min of cangrelor with P2Y12 reaction unit (PRU) values collected 12-24 h after initiation. Cangrelor doses were adjusted per protocol to maintain PRU values of 85-208. A total of 42 patients were included. Thirty-eight patients (90.5%) required temporary mechanical circulatory support while on cangrelor, and 4 patients (9.5%) received cangrelor as a bridge to procedure. The median cangrelor maintenance dose was 0.5 (interquartile range [IQR]: 0.375-0.75) mcg/kg/min, and the median time in therapeutic range with a PRU value between 85 and 208 was 66.6% (IQR: 39.6%-100%). No patients experienced stent thrombosis. A composite major adverse cardiovascular event occurred in 4 patients (9.5%), and major bleeding occurred in 16 patients (38.1%). Compared to empiric cangrelor dosing of 0.75 mcg/kg/min, PFT-guided cangrelor dose adjustment was associated with a median drug cost savings of $1605.60 (IQR: $0-4281.56). Utilizing PFT with cangrelor may allow for lower, individualized dosing while preventing stent thrombosis.


Assuntos
Monofosfato de Adenosina/análogos & derivados , Trombose , Adulto , Humanos , Estudos Retrospectivos , Administração Intravenosa , Redução de Custos
15.
Molecules ; 29(5)2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38474586

RESUMO

Cyclic adenosine monophosphate (cAMP) is an important second messenger in cells, mediating various stimulation signals such as the growth and development of organisms and stress and participating in regulating various biological processes of cells. This article explores the quantitative determination of cAMP in plants using High-Performance Liquid Chromatography (HPLC) and applies this method to analyzing the changes in cAMP content during the process of plant response to the bacterial quorum sensing signal N-acyl homoserine lactone (AHL). Research has shown that the optimal detection conditions for HPLC are as follows: the chromatographic column is Venusil MP C18 (2), the mobile phase is methanol-water (0.1% trifluoroacetic acid) (v:v, 10:90), the detection wavelength is 259 nm, the column temperature is 35 °C, and the flow rate is 0.8 mL/min. The precision of the standard sample of this method is 98.21%, the precision of the sample is 98.87%, and the recovery rate is 101.067%. The optimal extraction conditions for cAMP in Arabidopsis are to use 15% methanol ultrasonic extraction for 10 min, followed by a 40 °C water bath for 4 h. Bacterial AHL signal processing can significantly stimulate an increase in cAMP levels in Arabidopsis leaves and roots. The establishment of HPLC detection methods for the cAMP content in plants is of great significance for in-depth research on the signal transduction mechanisms of plant-bacterial interactions.


Assuntos
Acil-Butirolactonas , Arabidopsis , Cromatografia Líquida de Alta Pressão , Metanol , Bactérias , Plantas , AMP Cíclico , Água , Monofosfato de Adenosina
16.
J Virol ; 98(3): e0187423, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38329336

RESUMO

Subacute sclerosing panencephalitis (SSPE) is a rare but fatal late neurological complication of measles, caused by persistent measles virus (MeV) infection of the central nervous system. There are no drugs approved for the treatment of SSPE. Here, we followed the clinical progression of a 5-year-old SSPE patient after treatment with the nucleoside analog remdesivir, conducted a post-mortem evaluation of the patient's brain, and characterized the MeV detected in the brain. The quality of life of the patient transiently improved after the first two courses of remdesivir, but a third course had no further clinical effect, and the patient eventually succumbed to his condition. Post-mortem evaluation of the brain displayed histopathological changes including loss of neurons and demyelination paired with abundant presence of MeV RNA-positive cells throughout the brain. Next-generation sequencing of RNA isolated from the brain revealed a complete MeV genome with mutations that are typically detected in SSPE, characterized by a hypermutated M gene. Additional mutations were detected in the polymerase (L) gene, which were not associated with resistance to remdesivir. Functional characterization showed that mutations in the F gene led to a hyperfusogenic phenotype predominantly mediated by N465I. Additionally, recombinant wild-type-based MeV with the SSPE-F gene or the F gene with the N465I mutation was no longer lymphotropic but instead efficiently disseminated in neural cultures. Altogether, this case encourages further investigation of remdesivir as a potential treatment of SSPE and highlights the necessity to functionally understand SSPE-causing MeV.IMPORTANCEMeasles virus (MeV) causes acute, systemic disease and remains an important cause of morbidity and mortality in humans. Despite the lack of known entry receptors in the brain, MeV can persistently infect the brain causing the rare but fatal neurological disorder subacute sclerosing panencephalitis (SSPE). SSPE-causing MeVs are characterized by a hypermutated genome and a hyperfusogenic F protein that facilitates the rapid spread of MeV throughout the brain. No treatment against SSPE is available, but the nucleoside analog remdesivir was recently demonstrated to be effective against MeV in vitro. We show that treatment of an SSPE patient with remdesivir led to transient clinical improvement and did not induce viral escape mutants, encouraging the future use of remdesivir in SSPE patients. Functional characterization of the viral proteins sheds light on the shared properties of SSPE-causing MeVs and further contributes to understanding how those viruses cause disease.


Assuntos
Monofosfato de Adenosina , Alanina , Vírus do Sarampo , Sarampo , Panencefalite Esclerosante Subaguda , Proteínas Virais , Pré-Escolar , Humanos , Monofosfato de Adenosina/administração & dosagem , Monofosfato de Adenosina/análogos & derivados , Monofosfato de Adenosina/uso terapêutico , Alanina/administração & dosagem , Alanina/análogos & derivados , Alanina/uso terapêutico , Autopsia , Encéfalo/metabolismo , Encéfalo/patologia , Encéfalo/virologia , Progressão da Doença , Evolução Fatal , Genoma Viral/genética , Sequenciamento de Nucleotídeos em Larga Escala , Sarampo/complicações , Sarampo/tratamento farmacológico , Sarampo/virologia , Vírus do Sarampo/efeitos dos fármacos , Vírus do Sarampo/genética , Vírus do Sarampo/metabolismo , Proteínas Mutantes/análise , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Qualidade de Vida , RNA Viral/análise , RNA Viral/genética , Panencefalite Esclerosante Subaguda/tratamento farmacológico , Panencefalite Esclerosante Subaguda/etiologia , Panencefalite Esclerosante Subaguda/virologia , Proteínas Virais/análise , Proteínas Virais/genética , Proteínas Virais/metabolismo
17.
Biochemistry ; 63(5): 651-659, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38388156

RESUMO

AMPylation is a post-translational modification utilized by human and bacterial cells to modulate the activity and function of specific proteins. Major AMPylators such as human FICD and bacterial VopS have been studied extensively for their substrate and target scope in vitro. Recently, an AMP pronucleotide probe also facilitated the in situ analysis of AMPylation in living cells. Based on this technology, we here introduce a novel UMP pronucleotide probe and utilize it to profile uninfected and Vibrio parahaemolyticus infected human cells. Mass spectrometric analysis of labeled protein targets reveals an unexpected promiscuity of human nucleotide transferases with an almost identical target set of AMP- and UMPylated proteins. Vice versa, studies in cells infected by V. parahaemolyticus and its effector VopS revealed solely AMPylation of host enzymes, highlighting a so far unknown specificity of this transferase for ATP. Taken together, pronucleotide probes provide an unprecedented insight into the in situ activity profile of crucial nucleotide transferases, which can largely differ from their in vitro activity.


Assuntos
Nucleotídeos , Transferases , Humanos , Nucleotídeos/metabolismo , Transferases/metabolismo , Proteínas de Bactérias/química , Monofosfato de Adenosina/metabolismo , Processamento de Proteína Pós-Traducional
18.
Pediatrics ; 153(3)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38332740

RESUMO

OBJECTIVES: Remdesivir decreases the risk of SARS-CoV-2 infection progressing to severe disease in adults. This study evaluated remdesivir safety and pharmacokinetics in infants and children. METHODS: This was a phase 2/3, open-label trial in children aged 28 days to 17 years hospitalized for polymerase chain reaction-confirmed SARS-CoV-2 infection. Participants received for ≤10 days once-daily intravenous remdesivir doses defined using physiologically based pharmacokinetic modeling (for ≥40 kg, 200 mg day 1, then 100 mg/day; for age ≥28 days and ≥3 to <40 kg, 5 mg/kg day 1, then 2.5 mg/kg/day). Sparse pharmacokinetic samples were analyzed using population-pharmacokinetic approaches for remdesivir and metabolites GS-704277 and GS-441524. RESULTS: Among 53 participants, at enrollment the median (Q1, Q3) number of days of COVID-19 symptoms was 5 (3, 7) and hospitalization was 1 (1, 3). Underlying conditions included obesity in 19 (37%), asthma in 11 (21%), and cardiac disorders in 11 (21%). Median duration of remdesivir treatment was 5 days (range, 1-10). Remdesivir treatment had no new apparent safety trends. Two participants discontinued treatment because of adverse events including elevated transaminases; both had elevated transaminases at baseline. Three deaths occurred during treatment (and 1 after). When compared with phase 3 adult data, estimated mean pediatric parameters (area under the concentration-time curve over 1 dosing interval, AUCτ, Cmax, and Cτ) were largely overlapping but modestly increased (remdesivir, 33%-129%; GS-704277, 37%-124%; GS-441524, 0%-60%). Recovery occurred for 62% of participants on day 10 and 83% at last assessment. CONCLUSIONS: In infants and children with COVID-19, the doses of remdesivir evaluated provided drug exposure similar to adult dosing. In this study with a small sample size, no new safety concerns were observed.


Assuntos
Monofosfato de Adenosina/análogos & derivados , Alanina/análogos & derivados , COVID-19 , Criança Hospitalizada , Adulto , Lactente , Humanos , Criança , Tratamento Farmacológico da COVID-19 , SARS-CoV-2 , Pirróis , Transaminases
19.
J Nutr Biochem ; 127: 109602, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38373509

RESUMO

This study evaluated the effect of vitamin D3 (VIT D3) supplementation on the enzymatic activities and density of ectonucleoside triphosphate diphosphohydrolase (E-NTPDase), ecto-5-nucleotidase (E-5'-NT), adenosine deaminase (ADA), as well as the density of P2 × 7R, P2Y12R, A1R, A2AR receptors, IL-1ß, and oxidative parameters in type 2 diabetic rats. Forty male Wistar rats were fed a high carbohydrate-high fat diet (HCHFD) and received an intraperitoneal injection containing a single dose of streptozotocin (STZ, 35 mg/kg). Animals were divided into four groups: 1) control; 2) control/VIT D3 12 µg/kg; 3) diabetic; and 4) diabetic/VIT D3 12 µg/kg. Results show that VIT D3 reduced blood glucose, ATP hydrolysis, ADA activity, P2Y12R density (platelets), as well as ATP, ADP, and AMP hydrolysis and ADA activity (synaptosomes). Moreover, VIT D3 increased insulin levels and AMP hydrolysis (platelets) and improved antioxidant defense. Therefore, we suggest that VIT D3 treatment modulates hyperglycemia-induced changes via purinergic enzymes and receptor expression, consequently attenuating insulin homeostasis dysregulation in the diabetic state.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Insulinas , Ratos , Masculino , Animais , Ratos Wistar , Colecalciferol/farmacologia , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/tratamento farmacológico , Dieta Hiperlipídica/efeitos adversos , Vitaminas , Monofosfato de Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo
20.
Brain Res Bull ; 209: 110909, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38402994

RESUMO

BACKGROUND: The efficacy of acupuncture at Zusanli (ST36) in alleviating lower-limb pain is widely acknowledged in clinical practice, while its underlying mechanism remains incompletely elucidated. Our previous research had revealed that the prompt analgesia induced by needling-ST36 was accompanied by expression alterations in certain exco-nucleotidases within the sciatic nerve. Building upon this finding, the current work focused on NTPDase1, the primary ecto-nucleotidase in the human body, which converts ATP into AMP. METHODS: A 20-min acupuncture was administered unilaterally at the ST36 on rats with acute ankle arthritis. The pain thresholds of the injured hind paws were determined. Pharmacological interference was carried out by introducing the corresponding reagents to the sciatic nerve. ATP levels around the excised nerve were measured using a luciferase-luciferin assay. Live calcium imaging, utilizing the Fura 2-related-F340/F380 ratio, was conducted on Schwann cells in excised nerves and cultured rat SCs line, RSC96 cells. RESULTS: The analgesic effect induced by needling-ST36 was impaired when preventing ATP degradation via inhibiting NTPDase1 activities with ARL67156 or Ticlopidine. Conversely, increasing NTPDase1 activities with Apyrase duplicated the acupuncture effect. Similarly, preventing the conversion of AMP to adenosine via suppression of NT5E with AMP-CP hindered the acupuncture effect. Unexpectedly, impeded ATP hydrolysis ability and diminished NTPDase1 expression were observed in the treated group. Agonism at P2Y2Rs with ATP, UTP, or INS365 resulted in anti-nociception. Contrarily, antagonism at P2Y2Rs with Suramin or AR-C 118925xx prevented acupuncture analgesia. Immunofluorescent labeling demonstrated that the treated rats expressed more P2Y2Rs that were predominant in Schwann cells. Suppression of Schwann cells by inhibiting ErbB receptors also prevented acupuncture analgesia. Finally, living imaging on the excised nerves or RSC96 cells showed that agonism at P2Y2Rs indeed led to [Ca2+]i rise. CONCLUSION: These findings strongly suggest that the analgesic mechanism of needling-ST36 on the hypersensation in the lower limb partially relies on NTPDase1 activities in the sciatic nerve. In addition to facilitating adenosine signaling in conjunction with NT5E, most importantly, NTPDase1 may provide an appropriate low-level ATP milieu for the activation of P2Y2R in the sciatic nerve, particularly in Schwann cells.


Assuntos
Analgesia por Acupuntura , Terapia por Acupuntura , Antígenos CD , Artrite , Ratos , Humanos , Animais , Apirase , Tornozelo , Dor , Nervo Isquiático/metabolismo , Trifosfato de Adenosina/metabolismo , Analgésicos , Monofosfato de Adenosina , Adenosina , Pontos de Acupuntura
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