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1.
J Pak Med Assoc ; 74(9): 1630-1633, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39279066

RESUMO

Objectives: To evaluate the efficacy of CariSolv gel with respect to chemo-mechanical caries removal in primary molar teeth. METHODS: The cross-sectional study was conducted at the Department of Paediatric Dentistry, Bakhtawar Amin Dental College and Hospital, Multan, Pakistan, from July to December 2022, and comprised patients of either gender aged 6-12 years having vital, primary molar teeth with clinical and radiographic evidence of carious lesion. Freshly prepared CariSolv gel 0.2 ml to 1.0ml was applied to carious dentine for a minimum of 30 seconds, using chemo-mechanical caries removal hand instruments. The cavity preparation was rinsed and dried. Image caries detector dye was applied by micro brush for 10 seconds. After the cavity preparation was washed and dried, any red-stained dentine indicated residual infected dentine. A maximum of 3 chemo-mechanical caries removal cycles were allowed. Data was analysed using SPSS 26.0. RESULTS: Of the 134 patients, 74(55.2%) were boys and 60(44.8%) were girls. The overall mean age was 8.55±1.58 years. The procedure was successful in 115(85.8%) cases. Age and gender were not significantly associated with the outcome (p>0.05). CONCLUSIONS: Chemo-mechanical caries removal method using CariSolv gel was found to be a viable alternative to traditional drilling techniques for caries removal in primary molar teeth.


Assuntos
Cárie Dentária , Preparo da Cavidade Dentária , Géis , Leucina , Dente Molar , Dente Decíduo , Humanos , Cárie Dentária/terapia , Feminino , Masculino , Criança , Estudos Transversais , Preparo da Cavidade Dentária/métodos , Leucina/uso terapêutico , Leucina/administração & dosagem , Lisina/uso terapêutico , Resultado do Tratamento , Ácido Glutâmico
2.
Nat Commun ; 15(1): 7619, 2024 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-39223119

RESUMO

Isolated REM Sleep Behavior Disorder (iRBD) is considered a prodrome of Parkinson's disease (PD). We investigate whether the potentially disease-modifying compound acetyl-DL-leucine (ADLL; 5 g/d) has an effect on prodromal PD progression in 2 iRBD-patients. Outcome parameters are RBD-severity sum-score (RBD-SS-3), dopamine-transporter single-photon emission computerized tomography (DAT-SPECT) and metabolic "Parkinson-Disease-related-Pattern (PDRP)"-z-score in 18F-fluorodeoxyglucose positron emission tomography (FDG-PET). After 3 weeks ADLL-treatment, the RBD-SS-3 drops markedly in both patients and remains reduced for >18 months of ADLL-treatment. In patient 1 (female), the DAT-SPECT putaminal binding ratio (PBR) decreases in the 5 years pretreatment from normal (1.88) to pathological (1.22) and the patient's FDG-PET-PDRP-z-score rises from 1.72 to 3.28 (pathological). After 22 months of ADLL-treatment, the DAT-SPECT-PBR increases to 1.67 and the FDG-PET-PDRP-z-score stabilizes at 3.18. Similar results are seen in patient 2 (male): his DAT-SPECT-PBR rises from a pretreatment value of 1.42 to 1.72 (close to normal) and the FDG-PET-PDRP-z-score decreases from 1.02 to 0.30 after 18 months of ADLL-treatment. These results support exploration of whether ADLL may have disease-modifying properties in prodromal PD.


Assuntos
Proteínas da Membrana Plasmática de Transporte de Dopamina , Leucina , Doença de Parkinson , Tomografia por Emissão de Pósitrons , Transtorno do Comportamento do Sono REM , Tomografia Computadorizada de Emissão de Fóton Único , Humanos , Feminino , Transtorno do Comportamento do Sono REM/metabolismo , Transtorno do Comportamento do Sono REM/diagnóstico por imagem , Transtorno do Comportamento do Sono REM/tratamento farmacológico , Masculino , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Doença de Parkinson/metabolismo , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/patologia , Tomografia por Emissão de Pósitrons/métodos , Leucina/metabolismo , Leucina/análogos & derivados , Idoso , Pessoa de Meia-Idade , Encéfalo/metabolismo , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Fluordesoxiglucose F18/metabolismo , Corpo Estriado/metabolismo , Corpo Estriado/diagnóstico por imagem
3.
Int J Mol Sci ; 25(17)2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39273588

RESUMO

Our research explores leucine-based pseudo-proteins (LPPs) for advanced wound dressings, focusing on their effects on wound healing in an in vitro model. We assessed three types of LPP films for their ability to enhance wound closure rates and modulate cytokine production. They all significantly improved wound closure compared to traditional methods, with the 8L6 and copolymer films showing the most pronounced effects. Notably, the latter exhibited an optimal cytokine profile: an initial burst of pro-inflammatory TNF-α, followed by a controlled release of IL-6 during the proliferative phase and a significant increase in anti-inflammatory IL-10 during remodeling. This balanced cytokine response suggests that the copolymer film not only accelerates wound closure but also supports a well-regulated healing process, potentially reducing fibrosis and abnormal scarring, underscoring the potential of copolymer LPPs as advanced wound dressing materials. Future research will aim to elucidate the specific signaling pathways activated by the copolymer LPP to better understand its mechanism of action. Overall, LPP films offer a promising approach to improving wound care and could lead to more effective treatments for complex wounds.


Assuntos
Leucina , Cicatrização , Cicatrização/efeitos dos fármacos , Leucina/farmacologia , Humanos , Bandagens , Citocinas/metabolismo , Animais
4.
BMC Infect Dis ; 24(1): 963, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39266964

RESUMO

BACKGROUND: Nirmatrelvir/ritonavir (NM/r) is a safe and effective oral antiviral therapeutic used for treatment of mild-to-moderate COVID-19. Case reports described a clinical rebound syndrome whereby individuals experience a relapse of symptoms shortly after completing successful treatment. There is a lack of information on frequency of COVID-19 rebound after NM/r in routine clinical care, contributing factors, and clinical outcomes. METHODS: We reviewed electronic medical records to verify COVID-19 diagnosis, symptoms, and treatment with NM/r from January-June 2022. We defined COVID-19 clinical rebound as clear improvement in symptoms followed by recurrence or worsening of symptoms within 30 days of a five-day course of NM/r. RESULTS: We studied 268 adults with median age 57 (IQR 47, 68), 80% White race, 85% non-Hispanic ethnicity, 55% female, 80% vaccinated and boosted against SARS-CoV-2, and 68% with any co-morbidity. Sixteen (6.0%) of studied patients were determined to have COVID-19 clinical rebound. The median time from starting NM/r to rebound was 11 days (IQR 9, 13). Notable demographic and clinical factors with higher proportion (not statistically significant) among COVID-19 rebound patients were female sex (75% rebound vs. 54.5% no rebound), Black race (12.5% rebound vs. 4.9% no rebound), presence of at least one co-morbidity (81.3% rebound vs. 67.5% no rebound), and lack of prior SARS-CoV-2 infection (100% rebound vs. 92.9% no rebound). Only one patient (6.25%) was hospitalized after COVID-19 rebound. CONCLUSIONS: COVID-19 clinical rebound after treatment with NM/r is mild with favorable outcomes and more common than previously reported from real-world clinical care studies.


Assuntos
Antivirais , Tratamento Farmacológico da COVID-19 , COVID-19 , Ritonavir , SARS-CoV-2 , Humanos , Feminino , Ritonavir/uso terapêutico , Masculino , Pessoa de Meia-Idade , Idoso , Antivirais/uso terapêutico , COVID-19/epidemiologia , Indazóis/uso terapêutico , Recidiva , Estudos Retrospectivos , Resultado do Tratamento , Adulto , Lactamas , Leucina , Nitrilas , Prolina
5.
Proc Natl Acad Sci U S A ; 121(37): e2404175121, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39236245

RESUMO

We generated SARS-CoV-2 variants resistant to three SARS-CoV-2 main protease (Mpro) inhibitors (nirmatrelvir, TKB245, and 5h), by propagating the ancestral SARS-CoV-2WK521WT in VeroE6TMPRSS2 cells with increasing concentrations of each inhibitor and examined their structural and virologic profiles. A predominant E166V-carrying variant (SARS-CoV-2WK521E166V), which emerged when passaged with nirmatrelvir and TKB245, proved to be resistant to the two inhibitors. A recombinant SARS-CoV-2E166V was resistant to nirmatrelvir and TKB245, but sensitive to 5h. X-ray structural study showed that the dimerization of Mpro was severely hindered by E166V substitution due to the disruption of the presumed dimerization-initiating Ser1'-Glu166 interactions. TKB245 stayed bound to MproE166V, whereas nirmatrelvir failed. Native mass spectrometry confirmed that nirmatrelvir and TKB245 promoted the dimerization of Mpro, and compromised the enzymatic activity; the Ki values of recombinant MproE166V for nirmatrelvir and TKB245 were 117±3 and 17.1±1.9 µM, respectively, indicating that TKB245 has a greater (by a factor of 6.8) binding affinity to MproE166V than nirmatrelvir. SARS-CoV-2WK521WT selected with 5h acquired A191T substitution in Mpro (SARS-CoV-2WK521A191T) and better replicated in the presence of 5h, than SARS-CoV-2WK521WT. However, no significant enzymatic or structural changes in MproA191T were observed. The replicability of SARS-CoV-2WK521E166V proved to be compromised compared to SARS-CoV-2WK521WT but predominated over SARS-CoV-2WK521WT in the presence of nirmatrelvir. The replicability of SARS-CoV-2WK521A191T surpassed that of SARS-CoV-2WK521WT in the absence of 5h, confirming that A191T confers enhanced viral fitness. The present data should shed light on the understanding of the mechanism of SARS-CoV-2's drug resistance acquisition and the development of resistance-repellant COVID-19 therapeutics.


Assuntos
Proteases 3C de Coronavírus , Farmacorresistência Viral , SARS-CoV-2 , SARS-CoV-2/efeitos dos fármacos , Proteases 3C de Coronavírus/metabolismo , Proteases 3C de Coronavírus/antagonistas & inibidores , Proteases 3C de Coronavírus/química , Humanos , Chlorocebus aethiops , Animais , Farmacorresistência Viral/genética , Células Vero , Inibidores de Proteases/farmacologia , Inibidores de Proteases/química , Inibidores de Proteases/metabolismo , COVID-19/virologia , Antivirais/farmacologia , Betacoronavirus/efeitos dos fármacos , Cristalografia por Raios X , Lactamas , Leucina , Nitrilas , Prolina
7.
Nat Commun ; 15(1): 7522, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39215042

RESUMO

Activated Wnt/ß-catenin pathway is a key genetic event in liver cancer development. Solute carrier (SLC) transporters are promising drug targets. Here, we identify SLC13A3 as a drug-targetable effector downstream of ß-catenin in liver cancer. SLC13A3 expression is elevated in human liver cancer samples with gain of function (GOF) mutant CTNNB1, the gene encoding ß-catenin. Activation of ß-catenin up-regulates SLC13A3, leading to intracellular accumulation of endogenous SLC13A3 substrates. SLC13A3 is identified as a low-affinity transporter for glutathione (GSH). Silencing of SLC13A3 downregulates the leucine transporter SLC7A5 via c-MYC signaling, leading to leucine depletion and mTOR inactivation. Furthermore, silencing of SLC13A3 depletes GSH and induces autophagic ferroptosis in ß-catenin-activated liver cancer cells. Importantly, both genetic inhibition of SLC13A3 and a small molecule SLC13A3 inhibitor suppress ß-catenin-driven hepatocarcinogenesis in mice. Altogether, our study suggests that SLC13A3 could be a promising therapeutic target for treating human liver cancers with GOF CTNNB1 mutations.


Assuntos
Neoplasias Hepáticas , beta Catenina , Animais , Humanos , Masculino , Camundongos , Sistema y+ de Transporte de Aminoácidos/metabolismo , Sistema y+ de Transporte de Aminoácidos/genética , beta Catenina/metabolismo , beta Catenina/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Glutationa/metabolismo , Transportador 1 de Aminoácidos Neutros Grandes , Leucina/metabolismo , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Proteínas Proto-Oncogênicas c-myc/metabolismo , Proteínas Proto-Oncogênicas c-myc/genética , Serina-Treonina Quinases TOR/metabolismo , Via de Sinalização Wnt
8.
Amino Acids ; 56(1): 51, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39198298

RESUMO

Branched-chain amino acids (BCAAs)-leucine (Leu), isoleucine (Ile), and valine (Val)-are essential nutrients with significant roles in protein synthesis, metabolic regulation, and energy production. This review paper offers a detailed examination of the physico-chemical properties of BCAAs, their industrial synthesis, and their critical functions in various biological processes. The unique isomerism of BCAAs is presented, focusing on analytical challenges in their separation and quantification as well as their solubility characteristics, which are crucial for formulation and purification applications. The industrial synthesis of BCAAs, particularly using bacterial strains like Corynebacterium glutamicum, is explored, alongside methods such as genetic engineering aimed at enhancing production, detailing the enzymatic processes and specific precursors. The dietary uptake, distribution, and catabolism of BCAAs are reviewed as fundamental components of their physiological functions. Ultimately, their multifaceted impact on signaling pathways, immune function, and disease progression is discussed, providing insights into their profound influence on muscle protein synthesis and metabolic health. This comprehensive analysis serves as a resource for understanding both the basic and complex roles of BCAAs in biological systems and their industrial application.


Assuntos
Aminoácidos de Cadeia Ramificada , Transdução de Sinais , Aminoácidos de Cadeia Ramificada/metabolismo , Aminoácidos de Cadeia Ramificada/biossíntese , Corynebacterium glutamicum/metabolismo , Metabolismo Energético , Humanos , Animais , Leucina/metabolismo , Leucina/química
9.
PLoS One ; 19(8): e0307268, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39093910

RESUMO

INTRODUCTION: Understanding genetic contributors to sarcopenia (age-related loss of muscle strength and mass) is key to finding effective therapies. Variants of the bradykinin receptor 2 (BDKRB2) have been linked to athletic and muscle performance. The rs1799722-9 and rs5810761 T alleles have been shown to be overrepresented in endurance athletes, possibly due to increased transcriptional rates of the receptor. These variants have been rarely studied in older people or people with sarcopenia. METHODS: We performed a post hoc sub-study of the Leucine and ACE (LACE) inhibitor trial, which enrolled 145 participants aged ≥70 years with low grip strength and low gait speed. Participants' blood samples were genotyped for rs179972 using TaqMan and rs5810761 by amplification through Hotstar Taq. Genotypes were compared with outcomes of physical performance and body composition measures. RESULTS: Data from 136 individuals were included in the analysis. For rs1799722 the genotype frequency (TT: 17, CC: 48, CT: 71) remained in Hardy-Weinberg Equilibrium (HWE p = 0.248). There was no difference between the genotypes for six-Minute Walk Distance (6MWD) or Short Physical Performance Battery (SPPB). Men with the TT genotype had a significantly greater 6MWD than other genotypes (TT 400m vs CT 310m vs CC 314m, p = 0.027), and greater leg muscle mass (TT 17.59kg vs CT 15.04kg vs CC 15.65kg, p = 0.007). For rs5810761, the genotype frequency (-9-9: 31, +9+9: 43, -9+9: 60) remained in HWE (p = 0.269). The +9+9 genotype was associated with a significant change in SPPB score at 12 months (-9-9 0 vs -9+9 0 vs +9+9-1, p<0.001), suggesting an improvement. In men, the -9-9 genotype was associated with lower arm fat (-9-9 2.39kg vs -9+9 2.72kg vs +9+9 2.76kg, p = 0.019). CONCLUSION: In men, the rs1799722 TT genotype was associated with longer 6MWD and greater leg muscle mass, while the rs5810761 -9-9 genotype was associated with lower arm fat mass.


Assuntos
Desempenho Físico Funcional , Receptor B2 da Bradicinina , Sarcopenia , Humanos , Masculino , Idoso , Feminino , Receptor B2 da Bradicinina/genética , Sarcopenia/genética , Músculo Esquelético/patologia , Músculo Esquelético/fisiopatologia , Genótipo , Alelos , Polimorfismo de Nucleotídeo Único , Composição Corporal , Leucina/genética , Idoso de 80 Anos ou mais , Força da Mão , Força Muscular/genética
10.
Nat Metab ; 6(8): 1584-1600, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39117959

RESUMO

In humans, defects in leucine catabolism cause a variety of inborn errors in metabolism. Here, we use Caenorhabditis elegans to investigate the impact of mutations in mccc-1, an enzyme that functions in leucine breakdown. Through untargeted metabolomic and transcriptomic analyses we find extensive metabolic rewiring that helps to detoxify leucine breakdown intermediates via conversion into previously undescribed metabolites and to synthesize mevalonate, an essential metabolite. We also find that the leucine breakdown product 3,3-hydroxymethylbutyrate (HMB), commonly used as a human muscle-building supplement, is toxic to C. elegans and that bacteria modulate this toxicity. Unbiased genetic screens revealed interactions between the host and microbe, where components of bacterial pyrimidine biosynthesis mitigate HMB toxicity. Finally, upregulated ketone body metabolism genes in mccc-1 mutants provide an alternative route for biosynthesis of the mevalonate precursor 3-hydroxy-3-methylglutaryl-CoA. Our work demonstrates that a complex host-bacteria interplay rewires metabolism to allow host survival when leucine catabolism is perturbed.


Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Leucina , Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/genética , Animais , Leucina/metabolismo , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Interações entre Hospedeiro e Microrganismos , Mutação
11.
Int J Pharm ; 664: 124608, 2024 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-39163929

RESUMO

Multidrug-resistant tuberculosis (MDR-TB) and extensively drug-resistant tuberculosis (XDR-TB) continue as public health concerns. Inhaled drug therapy for TB has substantial benefits in combating the causal agent of TB (Mycobacterium tuberculosis). Pretomanid is a promising candidate in an optional combined regimen for XDR-TB. Pretomanid has demonstrated high potency against M. tuberculosis in both the active and latent phases. Conventional spray drying was used to formulate pretomanid as dry powder inhalers (DPIs) for deep lung delivery using a proliposomal system with a trehalose coarse excipient to enhance the drug solubility. Co-spray drying with L-leucine protected hygroscopic trehalose in formulations and improved powder aerosolization. Higher amounts of L-leucine (40-50 % w/w) resulted in the formation of mesoporous particles with high percentages of drug content and entrapment efficiency. The aerosolized powders demonstrated both geometric and median aerodynamic diameters < 5 µm with > 90 % emitted dose and > 50 % fine particle fraction. Upon reconstitution in simulated physiological fluid, the proliposomes completely converted to liposomes, exhibiting suitable particle sizes (130-300 nm) with stable colloids and improving drug solubility, leading to higher drug dissolution compared to the drug alone. Inhalable pretomanid showed higher antimycobacterial activity than pretomanid alone. The formulations were safe for all broncho-epithelial cell lines and alveolar macrophages, thus indicating their potential suitability for DPIs targeting pulmonary TB.


Assuntos
Antituberculosos , Inaladores de Pó Seco , Leucina , Lipossomos , Tamanho da Partícula , Tuberculose Pulmonar , Administração por Inalação , Antituberculosos/administração & dosagem , Antituberculosos/química , Antituberculosos/farmacologia , Antituberculosos/farmacocinética , Tuberculose Pulmonar/tratamento farmacológico , Humanos , Leucina/química , Leucina/administração & dosagem , Trealose/química , Trealose/administração & dosagem , Aerossóis , Solubilidade , Excipientes/química , Pós , Liberação Controlada de Fármacos , Secagem por Atomização , Composição de Medicamentos/métodos , Química Farmacêutica/métodos , Mycobacterium tuberculosis/efeitos dos fármacos , Nitroimidazóis
12.
Langmuir ; 40(37): 19404-19411, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39213639

RESUMO

Lysine-leucine (LK) peptides have been used as model systems and platforms for 2D material design for decades. LK peptides are amphiphilic sequences designed to bind and fold at hydrophobic surfaces through hydrophobic leucine side chains and hydrophilic lysine side chains extending into the aqueous subphase. The hydrophobic periodicity of the sequence dictates the secondary structure at the interface. This robust design makes them ideal candidates for controlling interfacial chemistry. This study presents the de novo design and characterization of two novel peptides: LRα14 and LHα14, which substitute lysine with arginine and histidine, respectively, in the helical LKα14 sequence. This modification is intended to expand the LK peptide platform to a new basic interfacial chemistry. We explore the stability of the new LRα14 and LHα14 designs with respect to changes in pH and salt concentration in bulk solution and at the interface using circular dichroism (UV-CD) and vibrational sum-frequency generation spectroscopy, respectively. Notably, the structural stability of the peptides remains unaffected across a wide range of pH and ionic strength values. At the same time, the variation of side-chain chemistry leads to a wide spectrum of interfacial water structures. By extension of the LK platform to include arginine and histidine, this study broadens the toolbox for designing tailored interfacial chemistries with applications in material and biomedical sciences.


Assuntos
Peptídeos , Peptídeos/química , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Lisina/química , Leucina/química , Tensoativos/química , Dicroísmo Circular , Sequência de Aminoácidos
13.
J Med Virol ; 96(9): e29901, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39210614

RESUMO

The mortality and hospitalization rate by COVID-19 dropped significantly currently, but its seasonal outbreaks make antiviral treatment still vital. The mortality and hospitazation rate by COVID-19 dropped significantly currently, but its seasonal ourbreaks make antiviral treatment still vital. In our study, syrian golden hamsters were treated with molnupiravir and interferons (IFNs) after SARS-CoV-2 infection. Their weight changes, pathological changes, virus replication and inflammation levels were evaluated. In the IFNs single treatment, only IFN-α group reduced viral load (p < 0.05) and virus titer in hamster lungs. The TNF-α expression decreased significantly in both IFNs treatment at 2dpi. Histological and immunofluorescence results showed lung damage in the IFNs groups were milder at 4dpi. In the molnupiravir/IFN-α combination treatment, weight loss and virus replication in lung were significantly decreased in the mono-molnupiravir group and combination group (p < 0.05), the expression of IL-6, TNF-α, IL-1ß and MIP-1α also decreased significantly (p < 0.05), but the combination treatment was not more effective than the mono-molnupiravir treatment. Histological and immunofluorescence results showed the lung damage and inflammation in mono-molnupiravir and combination groups were milder. In summary, IFNs treatment had anti-inflammatory effect against SARS-CoV-2, only IFN-α showed a weak antiviral effect. Molnupiravir/IFN-α combination treatment was effective against SARS-CoV-2 but was not superior to mono-molnupiravir treatment. IFN-α could be considered for immunocompromised patients to stimulate and activate early immune responses.


Assuntos
Antivirais , Tratamento Farmacológico da COVID-19 , Hidroxilaminas , Pulmão , Mesocricetus , SARS-CoV-2 , Carga Viral , Replicação Viral , Animais , Antivirais/uso terapêutico , Antivirais/farmacologia , Pulmão/virologia , Pulmão/patologia , Pulmão/efeitos dos fármacos , Replicação Viral/efeitos dos fármacos , SARS-CoV-2/efeitos dos fármacos , Carga Viral/efeitos dos fármacos , Hidroxilaminas/uso terapêutico , Hidroxilaminas/farmacologia , Cricetinae , Modelos Animais de Doenças , COVID-19/imunologia , COVID-19/virologia , Citidina/análogos & derivados , Citidina/uso terapêutico , Citidina/farmacologia , Quimioterapia Combinada , Interferon-alfa/uso terapêutico , Interferon-alfa/farmacologia , Citocinas/metabolismo , Interferons/uso terapêutico , Masculino , Leucina/análogos & derivados , Leucina/uso terapêutico , Leucina/farmacologia
14.
PLoS One ; 19(8): e0309324, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39163364

RESUMO

Plasma levels of branched-chain amino acids and their metabolites, the branched-chain ketoacids are increased in insulin resistance. Our previous studies showed that leucine and its metabolite KIC suppress insulin-stimulated glucose uptake in L6 myotubes along with the activation of the S6K1-IRS-1 pathway. Because other tissue and fiber types can be differentially regulated by KIC, we analyzed the effect of KIC gavage on whole-body insulin sensitivity and insulin signaling in vivo. We hypothesized that KIC gavage would reduce whole-body insulin sensitivity and increase S6K1-IRS-1 phosphorylation in various tissues and muscle fibers. Five-week-old male Sprague-Dawley rats were starved for 24 hours and then gavaged with 0.75ml/100g of water, leucine (22.3g/L) or KIC (30g/L) twice, ten minutes apart. They were then euthanized at different time points post-gavage (0.5-3h), and muscle, liver, and heart tissues were dissected. Other sets of gavaged animals underwent an insulin tolerance test. Phosphorylation (ph) of S6K1 (Thr389), S6 (Ser235/6) and IRS-1 (Ser612) was increased at 30 minutes post leucine gavage in skeletal muscles irrespective of fiber type. Ph-S6 (Ser235/6) was also increased in liver and heart 30 minutes after leucine gavage. KIC gavage increased ph-S6 (Ser235/6) in the liver. Neither Leucine nor KIC influenced whole-body insulin tolerance, nor ph-Akt (Ser473) in skeletal muscle and heart. BCKD-E1 α abundance was highest in the heart and liver, while ph-BCKD-E1 α (Ser293) was higher in the gastrocnemius and EDL compared to the soleus. Our data suggests that only leucine activates the S6K1-IRS-1 signaling axis in skeletal muscle, liver and heart, while KIC only does so in the liver. The effect of leucine and KIC on the S6K1-IRS-1 signaling pathway is uncoupled from whole-body insulin sensitivity. These results suggest that KIC and leucine may not induce insulin resistance, and the contributions of other tissues may regulate whole-body insulin sensitivity in response to leucine/KIC gavage.


Assuntos
Resistência à Insulina , Insulina , Cetoácidos , Leucina , Ratos Sprague-Dawley , Transdução de Sinais , Animais , Masculino , Leucina/metabolismo , Leucina/farmacologia , Transdução de Sinais/efeitos dos fármacos , Insulina/metabolismo , Insulina/sangue , Ratos , Fosforilação/efeitos dos fármacos , Cetoácidos/metabolismo , Músculo Esquelético/metabolismo , Músculo Esquelético/efeitos dos fármacos , Proteínas Substratos do Receptor de Insulina/metabolismo , Fígado/metabolismo , Fígado/efeitos dos fármacos , Fibras Musculares Esqueléticas/metabolismo , Fibras Musculares Esqueléticas/efeitos dos fármacos
15.
Nat Commun ; 15(1): 6503, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39090095

RESUMO

The COVID-19 pandemic has led to the deaths of millions of people and severe global economic impacts. Small molecule therapeutics have played an important role in the fight against SARS-CoV-2, the virus responsible for COVID-19, but their efficacy has been limited in scope and availability, with many people unable to access their benefits, and better options are needed. EDP-235 is specifically designed to inhibit the SARS-CoV-2 3CLpro, with potent nanomolar activity against all SARS-CoV-2 variants to date, as well as clinically relevant human and zoonotic coronaviruses. EDP-235 maintains potency against variants bearing mutations associated with nirmatrelvir resistance. Additionally, EDP-235 demonstrates a ≥ 500-fold selectivity index against multiple host proteases. In a male Syrian hamster model of COVID-19, EDP-235 suppresses SARS-CoV-2 replication and viral-induced hamster lung pathology. In a female ferret model, EDP-235 inhibits production of SARS-CoV-2 infectious virus and RNA at multiple anatomical sites. Furthermore, SARS-CoV-2 contact transmission does not occur when naïve ferrets are co-housed with infected, EDP-235-treated ferrets. Collectively, these results demonstrate that EDP-235 is a broad-spectrum coronavirus inhibitor with efficacy in animal models of primary infection and transmission.


Assuntos
Antivirais , COVID-19 , Proteases 3C de Coronavírus , SARS-CoV-2 , Replicação Viral , Animais , Cricetinae , Feminino , Humanos , Masculino , Antivirais/farmacologia , Chlorocebus aethiops , Proteases 3C de Coronavírus/antagonistas & inibidores , Proteases 3C de Coronavírus/metabolismo , COVID-19/virologia , COVID-19/transmissão , Tratamento Farmacológico da COVID-19 , Modelos Animais de Doenças , Furões , Lactamas , Leucina , Pulmão/virologia , Pulmão/efeitos dos fármacos , Pulmão/patologia , Mesocricetus , Nitrilas , Compostos Orgânicos , Pandemias/prevenção & controle , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/virologia , Pneumonia Viral/transmissão , Pneumonia Viral/prevenção & controle , Prolina , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/genética , SARS-CoV-2/fisiologia , Células Vero , Replicação Viral/efeitos dos fármacos
16.
Nutrients ; 16(15)2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39125271

RESUMO

Leucine is a branched-chain amino acid that is present in protein, and it is an essential factor in activating the mechanistic target of the rapamycin complex 1 signaling pathway and increasing muscle protein synthesis. However, the loss of digestive function after total gastrectomy leads to impaired protein absorption, potentially failing to stimulate muscle protein synthesis. Therefore, this study aimed to investigate whether muscle protein synthesis is enhanced by oral skim milk administration after total gastrectomy. Male Sprague Dawley rats were divided into total gastrectomy (TG) and sham surgery (S) groups. After five weeks postoperatively, we orally administered skim milk to achieve 3.1 g protein/kg body weight and collected blood and gastrocnemius muscle. The gastrocnemius muscle weight was significantly lower in the TG group than in the S group (p < 0.05). The increase in plasma leucine concentration was significantly lower in the TG group than in the S group (p < 0.05). The skeletal muscle protein synthesis and the phosphorylation of p70S6K and 4E-BP1 showed a similar increase in both groups. Even after TG, muscle protein synthesis was stimulated by consuming skim milk, accompanied by a sufficient rise in plasma leucine concentration.


Assuntos
Gastrectomia , Leucina , Leite , Proteínas Musculares , Músculo Esquelético , Ratos Sprague-Dawley , Animais , Masculino , Músculo Esquelético/metabolismo , Músculo Esquelético/efeitos dos fármacos , Proteínas Musculares/biossíntese , Proteínas Musculares/metabolismo , Leucina/administração & dosagem , Leucina/farmacologia , Leite/química , Fosforilação , Ratos , Administração Oral , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Biossíntese de Proteínas/efeitos dos fármacos , Peptídeos e Proteínas de Sinalização Intracelular
17.
Age Ageing ; 53(8)2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39141078

RESUMO

BACKGROUND: Molnupiravir and nirmatrelvir-ritonavir are orally administered pharmacotherapies for mild to moderate COVID-19. However, the effectiveness of these drugs among very old (≥80 years), hospitalised patients remains unclear, limiting the risk-benefit assessment of these antivirals in this specific group. This study investigates the effectiveness of these antivirals in reducing mortality among this group of hospitalised patients with COVID-19. METHODS: Using a territory-wide public healthcare database in Hong Kong, a target trial emulation study was conducted with data from 13 642 eligible participants for the molnupiravir trial and 9553 for the nirmatrelvir-ritonavir trial. The primary outcome was all-cause mortality. Immortal time and confounding bias was minimised using cloning-censoring-weighting approach. Mortality odds ratios were estimated by pooled logistic regression after adjusting confounding biases by stabilised inverse probability weights. RESULTS: Both molnupiravir (HR: 0.895, 95% CI: 0.826-0.970) and nirmatrelvir-ritonavir (HR: 0.804, 95% CI: 0.678-0.955) demonstrated moderate mortality risk reduction among oldest-old hospitalised patients. No significant interaction was observed between oral antiviral treatment and vaccination status. The 28-day risk of mortality was lower in initiators than non-initiators for both molnupiravir (risk difference: -1.09%, 95% CI: -2.29, 0.11) and nirmatrelvir-ritonavir (risk difference: -1.71%, 95% CI: -3.30, -0.16) trials. The effectiveness of these medications was observed regardless of the patients' prior vaccination status. CONCLUSIONS: Molnupiravir and nirmatrelvir-ritonavir are moderately effective in reducing mortality risk among hospitalised oldest-old patients with COVID-19, regardless of their vaccination status.


Assuntos
Antivirais , Tratamento Farmacológico da COVID-19 , Hospitalização , SARS-CoV-2 , Humanos , Antivirais/administração & dosagem , Antivirais/uso terapêutico , Masculino , Feminino , Idoso de 80 Anos ou mais , Hospitalização/estatística & dados numéricos , Hong Kong/epidemiologia , Administração Oral , Ritonavir/uso terapêutico , Ritonavir/administração & dosagem , COVID-19/mortalidade , COVID-19/epidemiologia , Hidroxilaminas/administração & dosagem , Hidroxilaminas/uso terapêutico , Resultado do Tratamento , Citidina/análogos & derivados , Citidina/administração & dosagem , Citidina/uso terapêutico , Leucina/análogos & derivados
18.
Epilepsy Behav ; 158: 109916, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39002276

RESUMO

BACKGROUND: Branched-chain amino acids (BCAAs) have been affected epilepsy, yet conclusions remain inconclusive, lacking causal evidence regarding whether BCAAs affect epilepsy. Systematic exploration of the causal relationship between BCAAs and epilepsy could hand out new ideas for the treatment of epilepsy. METHODS: Utilizing bidirectional Mendelian randomization (MR) study, we investigated the causal relationship between BCAA levels and epilepsy. BCAA levels from genome-wide association studies (GWAS), including total BCAAs, leucine levels, isoleucine levels, and valine levels, were employed. Causal relationships were explored applying the method of inverse variance-weighted (IVW) and MR-Egger, followed by sensitivity analyses of the results to evaluate heterogeneity and pleiotropy. RESULTS: Through strict genetic variant selection, we find some related SNPs, total BCAA levels (9), leucine levels (11), isoleucine levels (7), and valine levels (6) as instrumental variables for our MR analysis. Following IVW and sensitivity analysis, total BCAAs levels (OR = 1.14, 95 % CI = 1.019 âˆ¼ 1.285, P = 0.022) and leucine levels (OR = 1.15, 95 % CI = 1.018 âˆ¼ 1.304, P = 0.025) had significant correlation with epilepsy. CONCLUSIONS: There exists a causal relationship between the levels of total BCAAs and leucine with epilepsy, offering the new ideas into epilepsy potential mechanisms, holding significant implications for its prevention and treatment.


Assuntos
Aminoácidos de Cadeia Ramificada , Epilepsia , Estudo de Associação Genômica Ampla , Humanos , Aminoácidos de Cadeia Ramificada/sangue , Epilepsia/genética , Isoleucina/genética , Leucina/genética , Análise da Randomização Mendeliana , Polimorfismo de Nucleotídeo Único , Valina/genética
19.
Artigo em Inglês | MEDLINE | ID: mdl-39059318

RESUMO

Amino acids with various functions are abundant in living organisms and foods. Recent advances in analytical technology show that trace amounts of D-amino acids exist in living organisms and foods. In addition, studies show that these amino acids are involved in various physiological functions that differ from those of L-amino acids. Thus, a technique for analyzing DL-amino acids is required. However, the simultaneous separation and highly sensitive detection of DL-amino acids are complicated; therefore, highly sensitive analytical methods that can rapidly separate and identify compounds are required. We previously developed our original chiral resolution labeling reagents for the separation and highly sensitive detection of DL-amino acids. Here, we developed a simple method for the rapid separation and highly sensitive detection of DL-amino acids in various foods and beverages by liquid chromatography-mass spectrometry (LC-MS) using an octadecyl (C18) column after labeling with 1-fluoro-2,4-dinitrophenyl-5-D-leucine-N,N-dimethylethylenediamineamide (D-FDLDA; enantiomeric excess > 99.9 %). In addition, we synthesized a stable isotope (13C6)-labeled D-FDLDA (13C6-D-FDLDA) and established an analytical method that can accurately identify the peak of each DL-amino acid. MS sensitivity of DL-amino acids labeled with our labeling reagent was higher than that of conventional labeling reagents (Marfey's reagents). The labeling reagent was neither desorbed from each DL-amino acid nor degraded for at least 1 week at 4 °C. Furthermore, we determined the DL-amino acid contents in foods and beverages using the proposed method, and differences in the total amino acid content and D/L ratio in each food and beverage were observed.


Assuntos
Aminoácidos , Bebidas , Análise de Alimentos , Aminoácidos/análise , Aminoácidos/química , Bebidas/análise , Análise de Alimentos/métodos , Estereoisomerismo , Limite de Detecção , Reprodutibilidade dos Testes , Cromatografia Líquida/métodos , Leucina/química , Leucina/análise , Espectrometria de Massas/métodos , Modelos Lineares
20.
Antiviral Res ; 230: 105970, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39067667

RESUMO

Variants of SARS-CoV-2 pose significant challenges in public health due to their increased transmissibility and ability to evade natural immunity, vaccine protection, and monoclonal antibody therapeutics. The emergence of the highly transmissible Omicron variant and subsequent subvariants, characterized by an extensive array of over 32 mutations within the spike protein, intensifies concerns regarding vaccine evasion. In response, multiple antiviral therapeutics have received FDA emergency use approval, targeting the SARS-CoV-2 RNA-dependent RNA polymerase (RdRp) and main protease (Mpro) regions, known to have relatively fewer mutations across novel variants. In this study, we evaluated the efficacy of nirmatrelvir (PF-07321332) and other clinically significant SARS-CoV-2 antivirals against a diverse panel of SARS-CoV-2 variants, encompassing the newly identified Omicron subvariants XBB1.5 and JN.1, using live-virus antiviral assays. Our findings demonstrate that while the last Omicron subvariants exhibited heightened pathogenicity in our animal model, nirmatrelvir and other clinically relevant antivirals consistently maintained their efficacy against all tested variants, including the XBB1.5 subvariant.


Assuntos
Antivirais , Tratamento Farmacológico da COVID-19 , Hidroxilaminas , SARS-CoV-2 , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/genética , Antivirais/farmacologia , Antivirais/uso terapêutico , Animais , Hidroxilaminas/farmacologia , Hidroxilaminas/uso terapêutico , Camundongos , Humanos , Células Vero , Chlorocebus aethiops , COVID-19/virologia , Citidina/análogos & derivados , Citidina/farmacologia , Citidina/uso terapêutico , Monofosfato de Adenosina/análogos & derivados , Monofosfato de Adenosina/farmacologia , Monofosfato de Adenosina/uso terapêutico , Glicoproteína da Espícula de Coronavírus/genética , Mutação , Alanina/farmacologia , Alanina/análogos & derivados , Lactamas , Leucina , Nitrilas , Prolina
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