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1.
Cell ; 185(9): 1572-1587.e11, 2022 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-35452622

RESUMO

The large number of spike substitutions in Omicron lineage variants (BA.1, BA.1.1., and BA.2) could jeopardize the efficacy of SARS-CoV-2 vaccines. We evaluated in mice the protective efficacy of the Moderna mRNA-1273 vaccine against BA.1 before or after boosting. Whereas two doses of mRNA-1273 vaccine induced high levels of neutralizing antibodies against historical WA1/2020 strains, lower levels against BA.1 were associated with breakthrough infection and inflammation in the lungs. A primary vaccination series with mRNA-1273.529, an Omicron-matched vaccine, potently neutralized BA.1 but inhibited historical or other SARS-CoV-2 variants less effectively. However, boosting with either mRNA-1273 or mRNA-1273.529 vaccines increased neutralizing titers and protection against BA.1 and BA.2 infection. Nonetheless, the neutralizing antibody titers were higher, and lung viral burden and cytokines were slightly lower in mice boosted with mRNA-1273.529 and challenged with BA.1. Thus, boosting with mRNA-1273 or mRNA-1273.529 enhances protection against Omicron infection with limited differences in efficacy measured.


Assuntos
COVID-19 , SARS-CoV-2 , Vacina de mRNA-1273 contra 2019-nCoV , Animais , Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Humanos , Camundongos , SARS-CoV-2/genética , Vacinação , Vacinas Sintéticas , Vacinas de mRNA
2.
Immunity ; 50(3): 677-691.e13, 2019 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-30876875

RESUMO

Lineage-based vaccine design is an attractive approach for eliciting broadly neutralizing antibodies (bNAbs) against HIV-1. However, most bNAb lineages studied to date have features indicative of unusual recombination and/or development. From an individual in the prospective RV217 cohort, we identified three lineages of bNAbs targeting the membrane-proximal external region (MPER) of the HIV-1 envelope. Antibodies RV217-VRC42.01, -VRC43.01, and -VRC46.01 used distinct modes of recognition and neutralized 96%, 62%, and 30%, respectively, of a 208-strain virus panel. All three lineages had modest levels of somatic hypermutation and normal antibody-loop lengths and were initiated by the founder virus MPER. The broadest lineage, VRC42, was similar to the known bNAb 4E10. A multimeric immunogen based on the founder MPER activated B cells bearing the unmutated common ancestor of VRC42, with modest maturation of early VRC42 intermediates imparting neutralization breadth. These features suggest that VRC42 may be a promising template for lineage-based vaccine design.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Anti-HIV/imunologia , HIV-1/imunologia , Vacinas contra a AIDS/imunologia , Sequência de Aminoácidos , Linfócitos B/imunologia , Linhagem Celular , Células HEK293 , Infecções por HIV/imunologia , Humanos , Leucócitos Mononucleares , Estudos Longitudinais
3.
Proc Natl Acad Sci U S A ; 120(29): e2305896120, 2023 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-37428933

RESUMO

Vaccines have played a fundamental role in the control of infectious diseases. We previously developed a messenger RNA (mRNA) vaccine against HIV-1 that forms virus-like particles (VLPs) through coexpression of the viral envelope with Gag. Here, we applied the same principle to the design of a VLP-forming mRNA vaccine against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). To promote cognate interaction with simian immunodeficiency virus (SIV) Gag, we engineered different chimeric proteins encompassing the ectodomain and the transmembrane region of the SARS-CoV-2 Spike protein from the Wuhan-Hu-1 strain fused to the gp41 cytoplasmic tail of either HIV-1 (strain WITO) or SIV (strain mac239) with or without a partial truncation at amino acid 745 to enhance membrane expression. Upon cotransfection with SIV gag mRNA, the Spike-SIVCT.745 (SSt) chimera yielded the highest level of cell-surface expression and extracellular VLP release. Immunization of BALB/c mice with SSt+gag mRNA at 0, 4, and 16 wk induced higher titers of Spike-binding and autologous neutralizing antibodies at all time points compared to SSt mRNA alone. Furthermore, mice immunized with SSt+gag mRNA developed neutralizing antibodies effective against different variants of concern. These data demonstrate that the Gag/VLP mRNA platform can be successfully applied to vaccines against different agents for the prevention of infectious diseases of global relevance.


Assuntos
COVID-19 , Vírus da Imunodeficiência Símia , Humanos , Animais , Camundongos , Vacinas contra COVID-19/genética , Anticorpos Antivirais , SARS-CoV-2/genética , COVID-19/prevenção & controle , Anticorpos Neutralizantes , Glicoproteína da Espícula de Coronavírus/genética , Vírus da Imunodeficiência Símia/genética
4.
Environ Toxicol ; 39(7): 3930-3943, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38572829

RESUMO

The number of patients with chronic kidney disease (CKD) is increasing. Oral toxin adsorbents may provide some value. Several uremic toxins, including indoxyl sulfate (IS), p-cresol (PCS), acrolein, per- and poly-fluoroalkyl substances (PFAS), and inflammation markers (interleukin 6 [IL-6] and tumor necrosis factor [TNF]-alpha) have been shown to be related to CKD progression. A total of 81 patients taking oral activated charcoal toxin adsorbents (AC-134), which were embedded in capsules that dissolved in the terminal ileum, three times a day for 1 month, were recruited. The renal function, hemoglobulin (Hb), inflammation markers, three PFAS (PFOA, PFOS, and PFNA), and acrolein were quantified. Compared with the baseline, an improved glomerular filtration rate (GFR) and significantly lower acrolein were noted. Furthermore, the CKD stage 4 and 5 group had significantly higher concentrations of IS, PCS, IL-6, and TNF but lower levels of Hb and PFAS compared with the CKD Stage 3 group at baseline and after the intervention. Hb was increased only in the CKD Stage 3 group after the trial (p = .032). Acrolein did not differ between the different CKD stage groups. Patients with improved GFR (responders) (about 77%) and nonresponders had similar baseline GFR. Responders had higher acrolein and PFOA levels throughout the study and a more significant reduction in acrolein, indicating a better digestion function. Both the higher PFOA and lower acrolein may be related to improved eGFR (and possibly to improvements in proteinuria, which we did not measure. Proteinuria is associated with PFAS loss in the urine), AC-134 showed the potential to improve the GFR and decrease acrolein, which might better indicate renal function change. Future studies are needed with longer follow-ups.


Assuntos
Taxa de Filtração Glomerular , Insuficiência Renal Crônica , Humanos , Masculino , Feminino , Insuficiência Renal Crônica/fisiopatologia , Idoso , Pessoa de Meia-Idade , Taxa de Filtração Glomerular/efeitos dos fármacos , Cresóis , Acroleína , Adsorção , Toxinas Urêmicas , Concentração de Íons de Hidrogênio , Indicã/urina , Carvão Vegetal/química , Carvão Vegetal/administração & dosagem , Rim/efeitos dos fármacos , Rim/fisiopatologia , Cápsulas , Administração Oral
5.
J Biol Chem ; 298(4): 101819, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35283191

RESUMO

The conformationally dynamic HIV-1 envelope trimer (Env) is the target of broadly neutralizing antibodies (bnAbs) that block viral entry. Single-molecule Förster resonance energy transfer (smFRET) has revealed that HIV-1 Env exists in at least three conformational states on the virion. Prior to complete host-receptor engagement (State 3), Env resides most prevalently in the smFRET-defined State 1, which is preferentially recognized by most bnAbs that are elicited by natural infection. smFRET has also revealed that soluble trimers containing prefusion-stabilizing disulfide and isoleucine-to-proline substitutions reside primarily in State 2, which is a required intermediate between States 1 and 3. While high-resolution Env structures have been determined for States 2 and 3, the structure of these trimers in State 1 is unknown. To provide insight into the State 1 structure, here we characterized antigenic differences between smFRET-defined states and then correlated these differences with known structural differences between States 2 and 3. We found that cell surface-expressed Env was enriched in each state using state-enriching antibody fragments or small-molecule virus entry inhibitors and then assessed binding to HIV-1 bnAbs preferentially binding different states. We observed small but consistent differences in binding between Env enriched in States 1 and 2, and a more than 10-fold difference in binding to Env enriched in these states versus Env enriched in State 3. We conclude that structural differences between HIV-1 Env States 1 and 3 are likely more than 10-fold greater than those between States 1 and 2, providing important insight into State 1.


Assuntos
Infecções por HIV , HIV-1 , Produtos do Gene env do Vírus da Imunodeficiência Humana , Anticorpos Amplamente Neutralizantes/química , Anticorpos Amplamente Neutralizantes/metabolismo , Anticorpos Anti-HIV , HIV-1/metabolismo , Humanos , Conformação Proteica , Produtos do Gene env do Vírus da Imunodeficiência Humana/química , Produtos do Gene env do Vírus da Imunodeficiência Humana/metabolismo
6.
J Virol ; 94(13)2020 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-32295908

RESUMO

HIV-1 envelope (Env) trimers, stabilized in a prefusion-closed conformation, can elicit humoral responses capable of neutralizing HIV-1 strains closely matched in sequence to the immunizing strain. One strategy to increase elicited neutralization breadth involves vaccine priming of immune responses against a target site of vulnerability, followed by vaccine boosting of these responses with prefusion-closed Env trimers. This strategy has succeeded at the fusion peptide (FP) site of vulnerability in eliciting cross-clade neutralizing responses in standard vaccine-test animals. However, the breadth and potency of the elicited responses have been less than optimal. Here, we identify three mutations (3mut), Met302, Leu320, and Pro329, that stabilize the apex of the Env trimer in a prefusion-closed conformation and show antigenically, structurally, and immunogenically that combining 3mut with other approaches (e.g., repair and stabilize and glycine-helix breaking) yields well-behaved clade C-Env trimers capable of boosting the breadth of FP-directed responses. Crystal structures of these trimers confirmed prefusion-closed apexes stabilized by hydrophobic patches contributed by Met302 and Leu320, with Pro329 assuming canonically restricted dihedral angles. We substituted the N-terminal eight residues of FP (FP8, residues 512 to 519) of these trimers with the second most prevalent FP8 sequence (FP8v2, AVGLGAVF) and observed a 3mut-stabilized consensus clade C-Env trimer with FP8v2 to boost the breadth elicited in guinea pigs of FP-directed responses induced by immunogens containing the most prevalent FP8 sequence (FP8v1, AVGIGAVF). Overall, 3mut can stabilize the Env trimer apex, and the resultant apex-stabilized Env trimers can be used to expand the neutralization breadth elicited against the FP site of vulnerability.IMPORTANCE A major hurdle to the development of an effective HIV-1 vaccine is the elicitation of serum responses capable of neutralizing circulating strains of HIV, which are extraordinarily diverse in sequence and often highly neutralization resistant. Recently, we showed how sera with 20 to 30% neutralization breadth could, nevertheless, be elicited in standard vaccine test animals by priming with the most prevalent N-terminal 8 residues of the HIV-1 fusion peptide (FP8), followed by boosting with a stabilized BG505-envelope (Env) trimer. Here, we show that subsequent boosting with a 3mut-apex-stabilized consensus C-Env trimer, modified to have the second most prevalent FP8 sequence, elicits higher neutralization breadth than that induced by continued boosting with the stabilized BG505-Env trimer. With increased neutralizing breadth elicited by boosting with a heterologous trimer containing the second most prevalent FP8 sequence, the fusion peptide-directed immune-focusing approach moves a step closer toward realizing an effective HIV-1 vaccine regimen.


Assuntos
Vacinas contra a AIDS/imunologia , Produtos do Gene env do Vírus da Imunodeficiência Humana/genética , Produtos do Gene env do Vírus da Imunodeficiência Humana/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Feminino , Cobaias , Células HEK293 , Anticorpos Anti-HIV/imunologia , Soropositividade para HIV , HIV-1/imunologia , Humanos , Imunização Secundária , Peptídeos , Vacinas de Subunidades Antigênicas
7.
J Biomed Sci ; 27(1): 52, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32295602

RESUMO

BACKGROUND: Alveologenesis is the final stage of lung development to form air-exchanging units between alveoli and blood vessels. Genetic susceptibility or hyperoxic stress to perturb this complicated process can cause abnormal enlargement of alveoli and lead to bronchopulmonary dysplasia (BPD)-associated emphysema. Platelet-derived growth factor receptor α (PDGFRα) signaling is crucial for alveolar myofibroblast (MYF) proliferation and its deficiency is associated with risk of BPD, but posttranscriptional mechanisms regulating PDGFRα synthesis during lung development remain largely unexplored. Cytoplasmic polyadenylation element-binding protein 2 (CPEB2) is a sequence-specific RNA-binding protein and translational regulator. Because CPEB2-knockout (KO) mice showed emphysematous phenotypes, we investigated how CPEB2-controlled translation affects pulmonary development and function. METHODS: Respiratory and pulmonary functions were measured by whole-body and invasive plethysmography. Histological staining and immunohistochemistry were used to analyze morphology, proliferation, apoptosis and cell densities from postnatal to adult lungs. Western blotting, RNA-immunoprecipitation, reporter assay, primary MYF culture and ectopic expression rescue were performed to demonstrate the role of CPEB2 in PDGFRα mRNA translation and MYF proliferation. RESULTS: Adult CPEB2-KO mice showed emphysema-like dysfunction. The alveolar structure in CPEB2-deficient lungs appeared normal at birth but became simplified through the alveolar stage of lung development. In CPEB2-null mice, we found reduced proliferation of MYF progenitors during alveolarization, abnormal deposition of elastin and failure of alveolar septum formation, thereby leading to enlarged pulmonary alveoli. We identified that CPEB2 promoted PDGFRα mRNA translation in MYF progenitors and this positive regulation could be disrupted by H2O2, a hyperoxia-mimetic treatment. Moreover, decreased proliferating ability in KO MYFs due to insufficient PDGFRα expression was rescued by ectopic expression of CPEB2, suggesting an important role of CPEB2 in upregulating PDGFRα signaling for pulmonary alveologenesis. CONCLUSIONS: CPEB2-controlled translation, in part through promoting PDGFRα expression, is indispensable for lung development and function. Since defective pulmonary PDGFR signaling is a key feature of human BPD, CPEB2 may be a risk factor for BPD.


Assuntos
Proliferação de Células , Miofibroblastos/fisiologia , Fator de Crescimento Derivado de Plaquetas/genética , Biossíntese de Proteínas , Alvéolos Pulmonares/crescimento & desenvolvimento , Proteínas de Ligação a RNA/genética , Animais , Camundongos , Camundongos Knockout , Fator de Crescimento Derivado de Plaquetas/metabolismo , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/metabolismo
8.
Nat Chem Biol ; 13(10): 1115-1122, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28825711

RESUMO

The HIV-1 envelope (Env) spike is a conformational machine that transitions between prefusion (closed, CD4- and CCR5-bound) and postfusion states to facilitate HIV-1 entry into cells. Although the prefusion closed conformation is a potential target for inhibition, development of small-molecule leads has been stymied by difficulties in obtaining structural information. Here, we report crystal structures at 3.8-Å resolution of an HIV-1-Env trimer with BMS-378806 and a derivative BMS-626529 for which a prodrug version is currently in Phase III clinical trials. Both lead candidates recognized an induced binding pocket that was mostly excluded from solvent and comprised of Env elements from a conserved helix and the ß20-21 hairpin. In both structures, the ß20-21 region assumed a conformation distinct from prefusion-closed and CD4-bound states. Together with biophysical and antigenicity characterizations, the structures illuminate the allosteric and competitive mechanisms by which these small-molecule leads inhibit CD4-induced structural changes in Env.


Assuntos
Proteína gp120 do Envelope de HIV/química , Proteína gp41 do Envelope de HIV/química , Piperazinas/química , Bibliotecas de Moléculas Pequenas/química , Triazóis/química , Internalização do Vírus/efeitos dos fármacos , Cristalografia por Raios X , Proteína gp120 do Envelope de HIV/antagonistas & inibidores , Proteína gp41 do Envelope de HIV/antagonistas & inibidores , Modelos Moleculares , Piperazinas/farmacologia , Bibliotecas de Moléculas Pequenas/farmacologia , Relação Estrutura-Atividade , Triazóis/farmacologia
9.
Langmuir ; 34(19): 5474-5479, 2018 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-29697982

RESUMO

Unlike previous in vitro measurements where Amyloid ß (Aß) aggregation was studied in bulk solutions, we detect the structure change of the Aß aggregate on the surface of a wireless quartz-crystal-microbalance biosensor, which resembles more closely the aggregation process on the cell membrane. Using a 58 MHz quartz crystal, we monitored changes in the viscoelastic properties of the aggregate formed on the quartz surface from monomers to oligomers and then to fibrils, involving up to the 7th overtone mode (406 MHz). With atomic-force microscopy observations, we found a significant stiffness increase as well as thinning of the protein layer during the structure change from oligomer to fibrils at 20 h, which indicates that the stiffness of the fibril is much higher. Viscoelasticity can provide a significant index of fibrillation and can be useful for evaluating inhibitory medicines in drug development.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Técnicas de Microbalança de Cristal de Quartzo , Peptídeos beta-Amiloides/química , Técnicas Biossensoriais/instrumentação , Elasticidade , Fragmentos de Peptídeos/química , Viscosidade
10.
J Neurosci ; 36(50): 12661-12676, 2016 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-27810937

RESUMO

Cytoplasmic polyadenylation element binding protein 2 (CPEB2) is an RNA-binding protein and translational regulator. To understand the physiological function of CPEB2, we generated CPEB2 knock-out (KO) mice and found that most died within 3 d after birth. CPEB2 is highly expressed in the brainstem, which controls vital functions, such as breathing. Whole-body plethysmography revealed that KO neonates had aberrant respiration with frequent apnea. Nevertheless, the morphology and function of the respiratory rhythm generator and diaphragm neuromuscular junctions appeared normal. We found that upregulated translation of choline acetyltransferase in the CPEB2 KO dorsal motor nucleus of vagus resulted in hyperactivation of parasympathetic signaling-induced bronchoconstriction, as evidenced by increased pulmonary acetylcholine and phosphorylated myosin light chain 2 in bronchial smooth muscles. Specific deletion of CPEB2 in cholinergic neurons sufficiently caused increased apnea in neonatal pups and airway hyper-reactivity in adult mice. Moreover, inhalation of an anticholinergic bronchodilator reduced apnea episodes in global and cholinergic CPEB2-KO mice. Together, the elevated airway constriction induced by cholinergic transmission in KO neonates may account for the respiratory defect and mortality. SIGNIFICANCE STATEMENT: This study first generated and characterized cpeb2 gene-deficient mice. CPEB2-knock-out (KO) mice are born alive but most die within 3 d after birth showing no overt defects in anatomy. We found that the KO neonates showed severe apnea and altered respiratory pattern. Such respiratory defects could be recapitulated in mice with pan-neuron-specific or cholinergic neuron-specific ablation of the cpeb2 gene. Further investigation revealed that cholinergic transmission in the KO dorsal motor nucleus of vagus was overactivated because KO mice lack CPEB2-suppressed translation of the rate-limiting enzyme in the production of acetylcholine (i.e., choline acetyltransferase). Consequently, increased parasympathetic signaling leads to hyperactivated bronchoconstriction and abnormal respiration in the KO neonates.


Assuntos
Broncoconstrição/fisiologia , Colina O-Acetiltransferase/biossíntese , Sistema Nervoso Parassimpático/fisiologia , Proteínas de Ligação a RNA/genética , Transdução de Sinais/fisiologia , Nervo Vago/enzimologia , Animais , Broncoconstrição/efeitos dos fármacos , Broncodilatadores/farmacologia , Diafragma/inervação , Diafragma/fisiologia , Feminino , Genótipo , Pulmão/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Músculo Liso/fisiologia , Junção Neuromuscular/fisiologia , Sistema Nervoso Parassimpático/efeitos dos fármacos , Mecânica Respiratória/fisiologia , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima , Nervo Vago/efeitos dos fármacos
11.
Clin Exp Pharmacol Physiol ; 43(10): 875-82, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27385380

RESUMO

Anaemia is an important issue in patients undergoing haemodialysis. We aimed to identify a better dosing schedule of a fixed monthly dose of continuous erythropoietin receptor activator (CERA) in patients with chronic kidney disease (CKD) on haemodialysis. The CERA dosing schedule included 100 µg once monthly for 2 months, 50 µg twice monthly for 2 months and then 100 µg once monthly for two months. The effectiveness was determined by comparing haematocrit, nutritional status (serum protein and albumin) and inflammatory markers (tumour necrosis factor (TNF)-α, interleukin (IL)-1, IL-6 and Hepcidin) at the beginning of the study with those at the end of the study. Forty-seven out of 67 patients completed the trial. At the end, haematocrit was significantly higher (34.51 vs 33.22%, P=.004), levels of inflammatory markers were significantly lower (TNF-α (30.71 vs 35.67 ng/mL, P=.007), IL-6 (5.12 vs 7.95 ng/mL, P=.033), hepcidin (60.39 vs 74.39 ng/mL, P=.002)), blood glucose levels were significantly lower (112.40 vs 139.02 mg/dL, P=.003) and albumin was significantly higher (4.11 vs 3.98, P=.001). Patients with a better than average response had a lower initial number of red blood cells (3.3 vs 3.6 × 10(6) /mm(3) , P=.025) and a lower IL-1 (3.8 vs 12.9 ng/mL, P=.01). They also had significantly lower blood glucose levels at the end. (91.3 vs 124.0 mg/dL, P=.03). We demonstrate that a fixed monthly dose of CERA at a twice monthly dosing schedule improves nutrition, reduces the inflammation and corrects anaemia in patients on haemodialysis. This finding may provide a new strategy for treating CKD-related anaemia.


Assuntos
Anemia/sangue , Anemia/tratamento farmacológico , Apetite/efeitos dos fármacos , Hematínicos/administração & dosagem , Diálise Renal/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Anemia/epidemiologia , Apetite/fisiologia , Preparações de Ação Retardada/administração & dosagem , Esquema de Medicação , Feminino , Humanos , Inflamação/sangue , Inflamação/tratamento farmacológico , Falência Renal Crônica/sangue , Falência Renal Crônica/tratamento farmacológico , Falência Renal Crônica/epidemiologia , Masculino , Pessoa de Meia-Idade
12.
Molecules ; 21(6)2016 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-27338312

RESUMO

Ipomoea batatas has long been used in folk medicine for the treatment of hyperglycemia or as a food additive for the prevention of type 2 diabetes. However, neither the plant extract nor its active components have been evaluated systematically. In this work four crude extracts, including n-hexane- (IBH), 95% MeOH- (IBM), n-BuOH- (IBB), and H2O-soluble (IBW) fractions, were prepared by fractionation of a methanolic extract of purple I. batatas leaves. Twenty-four pure compounds 1-24 were then isolated by various chromatographic techniques and their structures identified from NMR and MS data. Glucose uptake assays in differentiated 3T3-L1 adipocytes and rat primary hepatocytes, as well as western blot analysis, were carried out to evaluate the antidiabetic activity of this species. The IBH crude fraction, with methyl decanoate (22) as a major and active compound, showed the greatest effect on glucose uptake, most likely via activation of Glut4 and regulation of the PI3K/AKT pathway. Quercetin 3-O-ß-d-sophoroside (1), quercetin (3), benzyl ß-d-glucoside (10), 4-hydroxy-3-methoxybenzaldehyde (12), and methyl decanoate (22) could be important components contributing to the antidiabetic effects. We conclude that purple I. batatas leaves have potential as an antidiabetic plant source and the active constituents 1, 3, 10, 12, and 22 are promising lead candidates for future investigation.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Glucose/metabolismo , Ipomoea batatas/química , Extratos Vegetais/farmacologia , Células 3T3-L1/efeitos dos fármacos , Animais , Metabolismo dos Carboidratos/efeitos dos fármacos , Diabetes Mellitus Tipo 2/metabolismo , Humanos , Camundongos , Fosfatidilinositol 3-Quinases/metabolismo , Extratos Vegetais/química , Folhas de Planta/química , Ratos
13.
Nucleic Acids Res ; 40(17): 8484-98, 2012 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-22730302

RESUMO

Cytoplasmic polyadenylation element-binding protein (CPEB)3 is a nucleocytoplasm-shuttling RNA-binding protein and predominantly resides in the cytoplasm where it represses target RNA translation. When translocated into the nucleus, CPEB3 binds to Stat5b and downregulates Stat5b-dependent transcription. In neurons, the activation of N-methyl-d-aspartate receptors (NMDARs) accumulates CPEB3 in the nucleus and redistributes CPEB3 in the nucleocytoplasmic compartments to control gene expression. Nonetheless, it is unclear which karyopherin drives the nuclear import of CPEB3 and which transport direction is most affected by NMDA stimulation to increase the nuclear pool of CPEB3. Here, we have identified that the karyopherins, IPO5 and CRM1, facilitate CPEB3 translocation by binding to RRM1 and a leucine-containing motif of CPEB3, respectively. NMDAR signaling increases RanBP1 expression and reduces the level of cytoplasmic GTP-bound Ran. These changes enhance CPEB3-IPO5 interaction, which consequently accelerates the nuclear import of CPEB3. This study uncovers a novel NMDA-regulated import pathway to facilitate the nuclear translocation of CPEB3.


Assuntos
Núcleo Celular/metabolismo , Proteínas de Ligação a RNA/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , beta Carioferinas/metabolismo , Transporte Ativo do Núcleo Celular , Animais , Células Cultivadas , Células HeLa , Humanos , Camundongos , Neurônios/metabolismo , Sinais de Exportação Nuclear , Sinais de Localização Nuclear , Domínios e Motivos de Interação entre Proteínas , RNA Interferente Pequeno , Proteínas de Ligação a RNA/química , Proteínas de Ligação a RNA/genética , Ratos , Ribonucleosídeo Difosfato Redutase , Transdução de Sinais , Proteínas Supressoras de Tumor/metabolismo , beta Carioferinas/antagonistas & inibidores , Proteína ran de Ligação ao GTP/metabolismo
14.
Oncol Lett ; 28(6): 578, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-39397800

RESUMO

The present study reports the potential of furosemide therapeutic activity in acute myeloid leukemia. A 26-year-old man with acute biphenotypic leukemia was treated with furosemide for suspected pulmonary edema, which was later deemed to be an infiltration of leukemia cells. Notably, the myeloblast population was rapidly eliminated during furosemide therapy. Bone marrow specimens biopsied at different time points were used for immunohistochemical analysis of the expression levels of tumor necrosis factor-α (TNF-α) and its two receptors, TNF-α receptors 1 and 2. The expression of TNF-α and its receptors in the bone marrow was markedly suppressed by furosemide, along with the elimination of the myeloblasts. Thus, it was hypothesized that the growth of myeloblasts in the patient depended on autocrine and/or paracrine TNF-α stimulation, whereas furosemide disrupted this positive feedback loop. Therefore, furosemide is suggested as an effective therapeutic agent for acute myeloid leukemia, at least as an adjunct to standard chemotherapy and gene-targeted therapy.

15.
Respir Med Case Rep ; 48: 102003, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38510661

RESUMO

The optimal treatment of acute chemical pneumonitis remains controversial. Here we report a healthy man with severe chemical pneumonitis caused by accidental inhalation of vanadium pentoxide. He presented with acute respiratory distress and received aggressive steroid therapy on arrival. Pulmonary symptoms and chest X-ray were improved dramatically the next day. The beneficial effect of steroid therapy for such a critical patient may outweigh the infection risk following inhalation of relative sterile material. We suggest early and aggressive steroid therapy may help shorten the disease course.

16.
Cell Rep ; 43(8): 114518, 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39028623

RESUMO

Soluble HIV-1 envelope (Env) trimers may serve as effective vaccine immunogens. The widely utilized SOSIP trimers have been paramount for structural studies, but the disulfide bond they feature between gp120 and gp41 constrains intersubunit mobility and may alter antigenicity. Here, we report an alternative strategy to generate stabilized soluble Env trimers free of covalent gp120-gp41 bonds. Stabilization was achieved by introducing an intrasubunit disulfide bond between the inner and outer domains of gp120, defined as interdomain lock (IDL). Correctly folded IDL trimers displaying a native-like antigenic profile were produced for HIV-1 Envs of different clades. Importantly, the IDL design abrogated CD4 binding while not affecting recognition by potent neutralizing antibodies to the CD4-binding site. By cryoelectron microscopy, IDL trimers were shown to adopt a closed prefusion configuration, while single-molecule fluorescence resonance energy transfer documented a high prevalence of native-like conformation. Thus, IDL trimers may be promising candidates as vaccine immunogens.


Assuntos
Proteína gp120 do Envelope de HIV , Proteína gp41 do Envelope de HIV , HIV-1 , Multimerização Proteica , Solubilidade , Proteína gp120 do Envelope de HIV/metabolismo , Proteína gp120 do Envelope de HIV/química , Proteína gp120 do Envelope de HIV/imunologia , Proteína gp41 do Envelope de HIV/metabolismo , Proteína gp41 do Envelope de HIV/química , Proteína gp41 do Envelope de HIV/imunologia , Humanos , HIV-1/metabolismo , HIV-1/imunologia , Anticorpos Neutralizantes/imunologia , Antígenos CD4/metabolismo , Conformação Proteica , Ligação Proteica
17.
J Am Chem Soc ; 135(20): 7738-43, 2013 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-23621606

RESUMO

Designing protein molecules that self-assemble into complex architectures is an outstanding goal in the area of nanobiotechnology. One design strategy for doing this involves genetically fusing together two natural proteins, each of which is known to form a simple oligomer on its own (e.g., a dimer or trimer). If two such components can be fused in a geometrically predefined configuration, that designed subunit can, in principle, assemble into highly symmetric architectures. Initial experiments showed that a 12-subunit tetrahedral cage, 16 nm in diameter, could be constructed following such a procedure [Padilla, J. E.; et al. Proc. Natl. Acad. Sci. U.S.A. 2001, 98, 2217; Lai, Y. T.; et al. Science 2012, 336, 1129]. Here we characterize multiple crystal structures of protein cages constructed in this way, including cages assembled from two mutant forms of the same basic protein subunit. The flexibilities of the designed assemblies and their deviations from the target model are described, along with implications for further design developments.


Assuntos
Nanoestruturas/química , Proteínas/química , Cristalografia por Raios X , Modelos Moleculares , Mutação , Tamanho da Partícula , Conformação Proteica , Proteínas/genética , Propriedades de Superfície
18.
Exp Hematol Oncol ; 12(1): 37, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-37046292

RESUMO

Surgical intervention is the first-line treatment in well-selected hepatocellular carcinoma (HCC) patients. However, only a few patients are suitable to receive radical surgery. We conducted a systematic review and meta-analysis to evaluate local control among four local ablative therapies in inoperable HCC patients, including radiofrequency ablation therapy (RFA), microwave ablation therapy (MWA), stereotactic ablative radiotherapy (SABR), and particle radiotherapy. The primary outcome was the local control rate and the secondary were regional and distant progression rates, overall survival rate, and adverse events. We included twenty-six studies from PubMed, EMBASE, and Cochrane Library databases. MWA (p < 0.001) and particle radiotherapy (p < 0.001) showed better performance of local control compared to RFA, while SABR (p = 0.276) showed a non-significant trend. However, SABR (p = 0.002) and particle radiotherapy (p < 0.001) showed better performance than RFA in HCCs of ≥ 30 mm in size. MWA showed a similar result to RFA while SABR and particle radiotherapy showed a lower survival rate in the 2-, 3-, and 4-year overall survival rates. Our results indicate that MWA, SABR and particle radiotherapy were safe and no inferior to RFA in local control rate. Besides, the local control rates of SABR and particle radiotherapy are better than RFA in HCC of ≥ 30 mm in size. As a result, we suggested that MWA, SABR and particle radiotherapy to be effective alternatives to RFA for inoperable HCC. Moreover, the tumor size should be taken into consideration for optimal treatment selection between local ablative therapies.

19.
Artigo em Inglês | MEDLINE | ID: mdl-36673861

RESUMO

BACKGROUND: We investigated the beneficial effect of add-on yoga with rehabilitation on blood pressure (BP) and hand grip strength in patients with chronic stroke (more than 90 days). METHODS: The study included patients 30-80 years of age who could stand independently for 1 min. Patients with psychiatric diseases or undergoing other therapies (like acupuncture) were excluded. The yoga group received training (1 h session twice weekly) with standard rehabilitation for 8 weeks. The control group received standard rehabilitation only. There were no differences in age, gender, hand grip strength, or BP between the two groups (16 subjects in each group) at baseline. RESULTS: The systolic BP (p = 0.01) decreased significantly, and the diastolic BP also decreased but not significantly in the yoga group (p = 0.11). For hand grip strength, both the unaffected hand (p = 0.00025) and the affected hand (p = 0.027) improved significantly. The control group showed no significant change in systolic or diastolic BP, nor did the grip strength change in both hands. Gender and age also affected the results of overall rehabilitation in that women benefited more from a decrease in BP, while men and young people (lower than the mean age of 60) benefited from hand grip strength improvement. CONCLUSIONS: Combining yoga with rehabilitation in chronic stroke patients can improve hand grip strength and decrease systolic BP.


Assuntos
Reabilitação do Acidente Vascular Cerebral , Acidente Vascular Cerebral , Yoga , Masculino , Humanos , Feminino , Adolescente , Pessoa de Meia-Idade , Pressão Sanguínea , Força da Mão/fisiologia , Exercício Físico , Acidente Vascular Cerebral/terapia , Mãos , Reabilitação do Acidente Vascular Cerebral/métodos
20.
Healthcare (Basel) ; 11(3)2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36767017

RESUMO

Erythropoiesis-stimulating agents (ESA) are used to treat anemia in hemodialysis (HD) patients. We investigated the role of inflammation and accumulation of environmental toxins (perfluorinated chemicals (PFCs), such as perfluorooctanoic acid and perfluorooctane sulfonate) in the erythropoietic response of HD patients who receive a fixed monthly continuous erythropoietin receptor activator (CERA) dosage. Forty-five patients underwent three successive phases of ESA treatment for two months each (phase one: 100 µg CERA once monthly; phase two: 50 µg CERA twice monthly; phase three: 100 µg CERA once monthly). Patient data were collected to determine the association of various factors with erythropoietic response (change in hematocrit). Liquid chromatography-tandem mass spectrometry was used to analyze perfluorinated chemicals. Twenty-eight patients exhibited a poor erythropoietic response that was significantly associated with: age > 80 years, initial hematocrit > 36%, glucose > 200 mg/dL, alanine aminotransferase > 21 U/L, c-reactive protein > 1 mg/dL, interleukin-6 > 10 ng/mL, lactate dehydrogenase ≤ 190 U/L, and chloride ≤ 93 mEq/L. There was also a borderline significant association between inflammation and PFCs, although PFCs failed to show any impact on ESA response. Age, glucose, chloride, liver function, and inflammation may be associated with cost-effective fixed CERA dosage administered at an increased frequency.

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