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1.
N Engl J Med ; 388(12): 1080-1091, 2023 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-36920778

RESUMEN

BACKGROUND: Lebrikizumab, a high-affinity IgG4 monoclonal antibody targeting interleukin-13, prevents the formation of the interleukin-4Rα-interleukin-13Rα1 heterodimer receptor signaling complex. METHODS: We conducted two identically designed, 52-week, randomized, double-blind, placebo-controlled, phase 3 trials; both trials included a 16-week induction period and a 36-week maintenance period. Eligible patients with moderate-to-severe atopic dermatitis (adults [≥18 years of age] and adolescents [12 to <18 years of age, weighing ≥40 kg]) were randomly assigned in a 2:1 ratio to receive either lebrikizumab at a dose of 250 mg (loading dose of 500 mg at baseline and week 2) or placebo, administered subcutaneously every 2 weeks. Outcomes for the induction period were assessed up to 16 weeks and are included in this report. The primary outcome was an Investigator's Global Assessment (IGA) score of 0 or 1 (indicating clear or almost clear skin; range, 0 to 4 [severe disease]) with a reduction (indicating improvement) of at least 2 points from baseline at week 16. Secondary outcomes included a 75% improvement in the Eczema Area and Severity Index score (EASI-75 response) and assessments of itch and of itch interference with sleep. Safety was also assessed. RESULTS: In trial 1, the primary outcome was met in 43.1% of 283 patients in the lebrikizumab group and in 12.7% of 141 patients in the placebo group (P<0.001); an EASI-75 response occurred in 58.8% and 16.2%, respectively (P<0.001). In trial 2, the primary outcome was met in 33.2% of 281 patients in the lebrikizumab group and in 10.8% of 146 patients in the placebo group (P<0.001); an EASI-75 response occurred in 52.1% and 18.1%, respectively (P<0.001). Measures of itch and itch interference with sleep indicated improvement with lebrikizumab therapy. The incidence of conjunctivitis was higher among patients who received lebrikizumab than among those who received placebo. Most adverse events during the induction period were mild or moderate in severity and did not lead to trial discontinuation. CONCLUSIONS: In the induction period of two phase 3 trials, 16 weeks of treatment with lebrikizumab was effective in adolescents and adults with moderate-to-severe atopic dermatitis. (Funded by Dermira; ADvocate1 and ADvocate2 ClinicalTrials.gov numbers, NCT04146363 and NCT04178967, respectively.).


Asunto(s)
Anticuerpos Monoclonales , Dermatitis Atópica , Adolescente , Adulto , Humanos , Lactante , Anticuerpos Monoclonales/efectos adversos , Anticuerpos Monoclonales/inmunología , Anticuerpos Monoclonales/uso terapéutico , Dermatitis Atópica/complicaciones , Dermatitis Atópica/tratamiento farmacológico , Dermatitis Atópica/inmunología , Método Doble Ciego , Interleucina-13/antagonistas & inhibidores , Interleucina-13/inmunología , Prurito/tratamiento farmacológico , Prurito/etiología , Prurito/inmunología , Índice de Severidad de la Enfermedad , Resultado del Tratamiento , Inmunoglobulina G/inmunología , Piel/efectos de los fármacos , Piel/inmunología
2.
J Sep Sci ; 47(5): e2300871, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38471978

RESUMEN

Postpartum hemorrhage can lead to a variety of maternal complications. Tao Hong Si Wu Decoction (THSWD) is a traditional Chinese medicine used for treating gynecological diseases. However, the active ingredients of THSWD and its pharmacological mechanism of treatment for postpartum blood stasis still remained unclear. In this study, 201 components were identified in THSWD ethanol extract using ultra-performance liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry, including 59 terpenoids and volatile oil, 61 Phenylpropanoids, 41 flavonoids, 22 alkaloids, and other 18 components. A total of 45 active compounds were identified in the blood and 33 active compounds were identified in the uterine. Taking the common components into the blood and into the uterus combined with network pharmacology. It was demonstrated that the active compounds can bind to the core target with good affinity through molecular docking. The results of this study will provide a reference for the quality control and pharmacodynamic material base research of THSWD.


Asunto(s)
Medicamentos Herbarios Chinos , Femenino , Humanos , Simulación del Acoplamiento Molecular , Medicamentos Herbarios Chinos/química , Cromatografía Liquida , Periodo Posparto , Cromatografía Líquida de Alta Presión/métodos
3.
J Environ Manage ; 351: 119738, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38061102

RESUMEN

Nitrogen (N) cycle is one of the most significant biogeochemical cycles driven by soil microorganisms on the earth. Exogenous humic substances (HS), which include composted-HS and artificial-HS, as a new soil additive, can improve the water retention capacity, cation exchange capacity and soil nutrient utilization, compensating for the decrease of soil HS content caused by soil overutilization. This paper systematically reviewed the contribution of three different sources of HS in the soil-plant system and explained the mechanisms of N transformation through physiological and biochemical pathways. HS convert the living space and living environment of microorganisms by changing the structure and condition of soil. Generally, HS can fix atmospheric and soil N through biotic and abiotic mechanisms, which improved the availability of N. Besides, HS transform the root structure of plants through physiological and biochemical pathways to promote the absorption of inorganic N by plants. The redox properties of HS participate in soil N transformation by altering the electron gain and loss of microorganisms. Moreover, to alleviate the energy crisis and environmental problems caused by N pollution, we also illustrated the mechanisms reducing soil N2O emissions by HS and the application prospects of artificial-HS. Eventually, a combination of indoor simulation and field test, molecular biology and stable isotope techniques are needed to systematically analyze the potential mechanisms of soil N transformation, representing an important step forward for understanding the relevance between remediation of environmental pollution and improvement of the N utilization in soil-plant system.


Asunto(s)
Sustancias Húmicas , Suelo , Sustancias Húmicas/análisis , Ecosistema , Plantas/metabolismo , Contaminación Ambiental , Nitrógeno/metabolismo
4.
Br J Dermatol ; 188(6): 740-748, 2023 05 24.
Artículo en Inglés | MEDLINE | ID: mdl-36994947

RESUMEN

BACKGROUND: Lebrikizumab is a novel, high-affinity monoclonal antibody that selectively binds to interleukin (IL)-13. OBJECTIVES: To evaluate the efficacy and safety of lebrikizumab monotherapy in adolescent and adult patients with moderate-to-severe atopic dermatitis (AD) over 52 weeks of treatment in ADvocate1 (NCT04146363) and ADvocate2 (NCT04178967). METHODS: Patients who responded to lebrikizumab 250 mg every 2 weeks (Q2W) at the end of the 16-week induction period were re-randomized 2 : 2 : 1 to receive lebrikizumab Q2W, lebrikizumab 250 mg every 4 weeks (Q4W) or placebo Q2W (lebrikizumab withdrawal) for 36 additional weeks. Response at week 16 was defined as achieving a 75% reduction in Eczema Area Severity Index (EASI 75) or an Investigator's Global Assessment (IGA) of 0 or 1, with a ≥ 2-point improvement and no rescue medication use. Multiple imputation was used to handle missing data. Intermittent use of topical therapy was permitted during the maintenance period. RESULTS: After 52 weeks, an IGA of 0 or 1 with a ≥ 2 point improvement was maintained by 71.2% of patients treated with lebrikizumab Q2W, 76.9% of patients treated with lebrikizumab Q4W and 47.9% of patients in the lebrikizumab withdrawal arm. EASI 75 was maintained by 78.4% of patients treated with lebrikizumab Q2W, 81.7% of patients treated with lebrikizumab Q4W and 66.4% of patients in the lebrikizumab withdrawal arm at week 52. Across treatment arms, proportions of patients using any rescue therapy were 14.0% (ADvocate1) and 16.4% (ADvocate2). During the combined induction and maintenance periods of ADvocate1 and ADvocate2, 63.0% of lebrikizumab-treated patients reported any treatment emergent adverse event, with most events (93.1%) being mild or moderate in severity. CONCLUSIONS: After a 16-week induction period with lebrikizumab Q2W, lebrikizumab Q2W and Q4W maintained similar improvement of the signs and symptoms of moderate-to-severe AD, with a safety profile consistent with previously published data.


Asunto(s)
Dermatitis Atópica , Adulto , Adolescente , Humanos , Dermatitis Atópica/tratamiento farmacológico , Dermatitis Atópica/diagnóstico , Anticuerpos Monoclonales Humanizados , Resultado del Tratamiento , Inyecciones Subcutáneas , Método Doble Ciego , Índice de Severidad de la Enfermedad , Anticuerpos Monoclonales/efectos adversos , Interleucina-13 , Inmunoglobulina A
5.
J Biopharm Stat ; 33(1): 60-76, 2023 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-35723946

RESUMEN

In early phase oncology drug development, single arm proof-of-concept (POC) studies are increasingly being used to drive the early decisions for future development of the drug. Decision-makings based on such studies, typically involving small sample size and early surrogate efficacy endpoints, are extremely challenging. In particular, given the tremendous competition in the development of immunotherapies, expedition of the most promising programs is desired. To this end, we have proposed a Bayesian three-tier approach to facilitate the decision-making process, inheriting all the benefits of Bayesian decision-making approaches and formally allowing the option of acceleration. With pre-specified Bayesian decision criteria, three types of decisions regarding the future development of the drug can be made: (1) terminating the program, (2) further investigation, considering totality of evidence or additional POC studies, and (3) accelerating the program. We further proposed a Bayesian adaptive three-tier (BAT) design, extending the decision-making approach to incorporate adaptive thresholds and allow for continuous monitoring of the study. We compare the performance of the proposed methods with some other existing methods through simulations.


Asunto(s)
Oncología Médica , Proyectos de Investigación , Humanos , Teorema de Bayes , Tamaño de la Muestra , Desarrollo de Medicamentos
6.
Zhongguo Zhong Yao Za Zhi ; 48(17): 4761-4773, 2023 Sep.
Artículo en Zh | MEDLINE | ID: mdl-37802815

RESUMEN

The potential anti-stroke active components in Taohong Siwu Decoction(THSWD) were identified by target cell trapping coupled with ultra-high performance liquid chromatography-quadrupole-time of flight mass spectrometry(UPLC-Q-TOF-MS). The underlying mechanism of active components in THSWD in the treatment of ischemic stroke(IS) was explored by network pharmacology, molecular docking, and experimental validation. The UPLC-Q-TOF-MS technology combined with the UNIFI data analysis platform was used to analyze the composition of the cellular fragmentation fluid after co-incubation of THSWD with target cells. The targets of potential active components and IS were collected by network pharmacology, and the common targets underwent protein-protein interaction(PPI), Gene Ontology(GO), and Kyoto Encyclopedia of Genes and Genomes(KEGG) signaling pathway enrichment analyses. The target cell trapping component-core target-signaling pathway network was constructed, and the active components were molecularly docked to the top targets in the PPI network, followed by pharmacodynamic validation in vitro. Fifteen active components were identified in the target cellular fragmentation fluid, including bicyclic monoterpenes, cyanoglycosides, flavonols, quinoid chalcones, phenylpropanoids, and tannins. As revealed by the analysis of network pharmacology, THSWD presumably regulated PI3K-AKT, FoxO, MAPK, Jak-STAT, VEGF, HIF-1, and other signaling pathways to affect inflammatory cascade reaction, angiogenesis, oxidative stress, pyroptosis, apoptosis, and other pathological processes via paeoniflorin, butylphthalide, dehydrated safflower yellow B, 3,4-dicaffeoylquinic acid, amygdalin, paeoniflorin, and ligusticolactone. Molecular docking and in vitro pharmacodynamic validation revealed that the target cell trapping active components could promote neovascularization in rat brain microvascular endothelial cells(rBMECs) in the oxygen-glucose deprivation/reoxygenation(OGD/R) model. The application of target cell trapping coupled with UPLC-Q-TOF-MS technology can rapidly screen out the potential active components in THSWD. The active components of THSWD can be predicted to intervene in the pathogenesis of IS through network pharmacology, and molecular docking combined with experimental validation can further clarify the efficacy, thus providing a theoretical basis for research ideas on the pharmacodynamic substance basis of traditional Chinese medicine compounds.


Asunto(s)
Medicamentos Herbarios Chinos , Accidente Cerebrovascular Isquémico , Animales , Ratas , Accidente Cerebrovascular Isquémico/tratamiento farmacológico , Simulación del Acoplamiento Molecular , Farmacología en Red , Células Endoteliales , Fosfatidilinositol 3-Quinasas , Medicamentos Herbarios Chinos/farmacología
7.
J Am Chem Soc ; 144(13): 5855-5863, 2022 04 06.
Artículo en Inglés | MEDLINE | ID: mdl-35333525

RESUMEN

As practitioners of organic chemistry strive to deliver efficient syntheses of the most complex natural products and drug candidates, further innovations in synthetic strategies are required to facilitate their efficient construction. These aspirational breakthroughs often go hand-in-hand with considerable reductions in cost and environmental impact. Enzyme-catalyzed reactions have become an impressive and necessary tool that offers benefits such as increased selectivity and waste limitation. These benefits are amplified when enzymatic processes are conducted in a cascade in combination with novel bond-forming strategies. In this article, we report a highly diastereoselective synthesis of MK-1454, a potent agonist of the stimulator of interferon gene (STING) signaling pathway. The synthesis begins with the asymmetric construction of two fluoride-bearing deoxynucleotides. The routes were designed for maximum convergency and selectivity, relying on the same benign electrophilic fluorinating reagent. From these complex subunits, four enzymes are used to construct the two bridging thiophosphates in a highly selective, high yielding cascade process. Critical to the success of this reaction was a thorough understanding of the role transition metals play in bond formation.


Asunto(s)
Productos Biológicos , Productos Biológicos/química , Catálisis
8.
Neoplasma ; 69(4): 807-819, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35471977

RESUMEN

This article reported the mechanism of Anlotinib in gastric cancer treatment. Gastric cancer cells were treated with Anlotinib (8 µM) and transfected by STING shRNA and STING vectors. Cell counting kit-8 assay, wounding healing assay, and Transwell experiment were applied for proliferation, migration, and invasion detection. PD-L1 fluorescence intensity in gastric cancer cells was explored by flow cytometry. IFN-ß level was researched by enzyme-linked immunosorbent reaction. Xenograft tumor experiment was performed by administering mice with Anlotinib and anti-PD-L1 antibody. Immunohistochemistry and western blot were used for proteins expression detection. Quantitative real-time reverse transcription-polymerase chain reaction was applied for mRNA expression detection. Hematoxylin and eosin staining was conducted on lung, liver, kidney, and cerebral cortex of mice. Gastric cancer cells treated with Anlotinib exhibited reduced proliferation, migration, and invasion (p<0.01). Anlotinib treatment reduced PCNA, CDK1, and MMP2 protein expressions and increased E-cadherin protein expression in gastric cancer cells (p<0.01). Anlotinib treatment suppressed PD-L1 expression and activated the cGAS-STING/IFN-ß pathway in gastric cancer cells (p<0.01). STING knockdown partially reversed the inhibition of Anlotinib on gastric cancer cells proliferation, migration, invasion, and immune escape (p<0.05 or p<0.01). However, STING overexpression exhibited the opposite effect. Anlotinib synergistically improved anti-tumor efficacy of anti-PD-L1 in vivo. Anlotinib synergistic anti-PD-L1 increased CD3+, CD8+ T cells, and activated the cGAS-STING/IFN-ß pathway in xenograft tumor. Anlotinib was non-toxic to lung, liver, cortex, and kidney. Anlotinib suppressed gastric cancer cells proliferation, migration, and immune escape by activating the cGAS-STING/IFN-ß pathway.


Asunto(s)
Quinolinas , Neoplasias Gástricas , Animales , Proliferación Celular , Humanos , Indoles , Ratones , Nucleotidiltransferasas/genética , Nucleotidiltransferasas/metabolismo , Quinolinas/farmacología , Neoplasias Gástricas/tratamiento farmacológico
9.
Biochem Biophys Res Commun ; 572: 20-26, 2021 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-34332325

RESUMEN

PYCR2 has previously been shown to be related to a range of malignancies including hepatocellular carcinoma and melanoma, but its mechanistic functions and prognostic relevance in colon cancer patients remain to be defined. Herein, we used the Oncomine, Human Protein Atlas, The Cancer Genome Atlas (TCGA), and UALCAN databases to explore the expression of this gene in different human cancer, after which the relationship between PYCR2 expression and patient clinicopathologic characteristics was evaluated. We utilized an in vitro approach to evaluate the association between PYCR2 expression and colon cancer cell proliferation, migration, invasion, and tumor microsphere formation. The cell apoptosis was analyzed by flow cytometry. Gene set enrichment analysis (GSEA) approaches were additionally used to probe signaling pathways related to PYCR2. These analyses confirmed that PYCR2 was upregulated in several cancer types including colon cancer, with such upregulation correlating with a poor patient prognosis and with malignant clinicopathological characteristics. PYCR2 expression was identified as an independent predictor of colon cancer patients' survival, and in vitro analyses suggested that knocking down this gene was sufficient to disrupt the proliferative, migratory, invasive, and microsphere formation activities of colon cancer cells. Moreover, shPYCR2 transfection induced colon cancer cell apoptosis. GSEA suggested that high PYCR2 expression correlates with the differential enrichment of the Wnt ß-catenin signaling, MYC targets, RNA polymerase, and Notch signaling pathways. Overall, these data indicate that PYCR2 is an important mediator of tumor progression and metastasis, and suggest that it may be a valuable prognostic indicator for colon cancer patient evaluation.


Asunto(s)
Neoplasias del Colon/metabolismo , Pirrolina Carboxilato Reductasas/metabolismo , Regulación hacia Arriba , Neoplasias del Colon/diagnóstico , Humanos , Células Tumorales Cultivadas
10.
IUBMB Life ; 71(10): 1634-1644, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31216116

RESUMEN

The underlying mechanisms and gene signatures of melanoma are unknown. In this study, three expression profile data sets (GSE65568, GSE100050, GSE114445) were integrated to identify candidate genes explaining the pathways and functions of melanoma. Expression data sets including 24 melanoma tumours and 13 normal skin samples were merged and analysed in detail. The three GSE profiles shared 431 differentially expressed genes (DEGs), including 227 upregulated genes, 200 downregulated genes and 4 differentially regulated genes. Moreover, the functions and signalling pathways of the shared DEGs with significant p-values were identified. The two most significant modules were filtered from the DEGs protein-protein interaction (PPI) network, which consisted of 284 nodes. We also plotted the prognostic value of hub genes from an online database. In summary, using integrated bioinformatic analysis, we have identified candidate DEGs and pathways in melanoma that could improve our understanding of the causes and underlying molecular events of melanoma, and these candidate genes and pathways could be therapeutic targets for melanoma.


Asunto(s)
Biomarcadores de Tumor/genética , Quimiocina CXCL10/genética , Melanoma/genética , Factor de Transcripción STAT1/genética , Biología Computacional , Supervivencia sin Enfermedad , Femenino , Perfilación de la Expresión Génica/métodos , Regulación Neoplásica de la Expresión Génica/genética , Redes Reguladoras de Genes/genética , Humanos , Masculino , Melanoma/patología , Proteínas de Neoplasias/genética , Transducción de Señal/genética , Transcriptoma/genética
12.
J Biopharm Stat ; 29(2): 287-305, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30359554

RESUMEN

Dose titration becomes more and more common in improving drug tolerability as well as determining individualized treatment doses, thereby maximizing the benefit to patients. Dose titration starting from a lower dose and gradually increasing to a higher dose enables improved tolerability in patients as the human body may gradually adapt to adverse gastrointestinal effects. Current statistical analyses mostly focus on the outcome at the end-of-study follow-up without considering the longitudinal impact of dose titration on the outcome. Better understanding of the dynamic effect of dose titration over time is important in early-phase clinical development as it could allow to model the longitudinal trend and predict the longer term outcome more accurately. We propose a parametric model with two empirical methods of modeling the error terms for a continuous outcome with dose titrations. Simulations show that both approaches of modeling the error terms work well. We applied this method to analyze data from a few clinical studies and achieved satisfactory results.


Asunto(s)
Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/prevención & control , Péptidos Similares al Glucagón/administración & dosificación , Hipoglucemiantes/administración & dosificación , Modelos Estadísticos , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos , Simulación por Computador , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/epidemiología , Péptido 1 Similar al Glucagón/agonistas , Péptidos Similares al Glucagón/efectos adversos , Péptidos Similares al Glucagón/uso terapéutico , Humanos , Hipoglucemiantes/efectos adversos , Hipoglucemiantes/uso terapéutico , Ensayos Clínicos Controlados Aleatorios como Asunto/estadística & datos numéricos , Resultado del Tratamiento
13.
J Org Chem ; 83(10): 5731-5750, 2018 05 18.
Artículo en Inglés | MEDLINE | ID: mdl-29663813

RESUMEN

Amide bond formation is one of the most important transformations in organic synthesis, drug development, and materials science. Efficient construction of amides has been among the most challenging tasks for organic chemists. Herein, we report a concise methodology for amide bond (-CONH-) formation assisted by vicinal group migration in alkylthio-functionalized enaminones (α-oxo ketene N, S-acetals) under mild conditions. Simple treatment of such enaminones with PhI(OAc)2 at ambient temperature in air afforded diverse multiply functionalized α,ß-unsaturated amides including ß-cyclopropylated acrylamides, in which a wide array of functional groups such as aryl, (hetero)aryl, alkenyl, and alkyl can be conveniently introduced to a ketene moiety. The reaction mechanism was investigated by exploring the origins of the amide oxygen and carbon atoms as well as isolation and structural characterization of the reaction intermediates. The amide bond formation reactions could also be efficiently performed under solventless mechanical milling conditions.

14.
Angew Chem Int Ed Engl ; 57(23): 6863-6867, 2018 06 04.
Artículo en Inglés | MEDLINE | ID: mdl-29689604

RESUMEN

Described here is an efficient stereoselective synthesis of vibegron enabled by an enzymatic dynamic kinetic reduction that proceeds in a high-pH environment. To overcome enzyme performance limitations under these conditions, a ketoreductase was evolved by a computationally and structurally aided strategy to increase cofactor stability through tighter binding.


Asunto(s)
Agonistas de Receptores Adrenérgicos beta 3/síntesis química , Pirimidinonas/síntesis química , Pirrolidinas/síntesis química , Biocatálisis , Concentración de Iones de Hidrógeno , Cinética , Modelos Moleculares , Oxidación-Reducción , Oxidorreductasas/química , Estereoisomerismo
15.
Biochim Biophys Acta ; 1858(8): 1914-25, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27207743

RESUMEN

Further discovery and design of new anticancer peptides are important for the development of anticancer therapeutics, and study on the detailed acting mechanism and structure-function relationship of peptides is critical for anticancer peptide design and application. In this study, a novel anticancer peptide ZXR-1 (FKIGGFIKKLWRSKLA) derived from a known anticancer peptide mauriporin was developed, and a mutant ZXR-2 (FKIGGFIKKLWRSLLA) with only one residue difference at the 14th position (Lys→Leu) was also engineered. Replacement of the lysine with leucine made ZXR-2 more potent than ZXR-1 in general. Even with only one residue mutation, the two peptides displayed distinct anticancer modes of action. ZXR-1 could translocate into cells, target on the mitochondria and induce cell apoptosis, while ZXR-2 directly targeted on the cell membranes and caused membrane lysis. The variance in their acting mechanisms might be due to the different amphipathicity and positive charge distribution. In addition, the two Ile-Leu pairs (3-10 and 7-14) in ZXR-2 might also play a role in improving its cytotoxicity. Further study on the structure-function relationship of the two peptides may be beneficial for the design of novel anticancer peptides and peptide based therapeutics.


Asunto(s)
Antineoplásicos/farmacología , Proteínas Reguladoras de la Apoptosis/farmacología , Apoptosis/efectos de los fármacos , Membrana Celular/efectos de los fármacos , Citotoxinas/farmacología , Péptidos/farmacología , Sustitución de Aminoácidos , Antineoplásicos/síntesis química , Antineoplásicos/química , Proteínas Reguladoras de la Apoptosis/síntesis química , Proteínas Reguladoras de la Apoptosis/química , Línea Celular Tumoral , Citotoxinas/síntesis química , Citotoxinas/química , Diseño de Fármacos , Ensayos de Selección de Medicamentos Antitumorales , Estabilidad de Medicamentos , Células HEK293 , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Mitocondrias/efectos de los fármacos , Péptidos/síntesis química , Péptidos/química , Venenos de Escorpión/química , Suero , Relación Estructura-Actividad
16.
Amino Acids ; 49(1): 193-202, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27778166

RESUMEN

Many lytic peptides contain a heptad sequence with leucine or isoleucine residues at "a" and "d" positions. However, their roles in the peptide-induced cytolytic process remain unclear. We have recently reported an anticancer lytic peptide ZXR-2 (FKIGGFIKKLWRSLLA), which contains a shortened zipper-like sequence with Ile/Leu at "a" and "d" positions. To understand the roles of these Ile/Leu residues, a series of analogs were constructed by sequentially replacing the Ile or Leu residue with alanine (Ala). Significant reduction of the cytolytic activity was observed when the Ile (3rd and 7th) and Leu (10th and 14th) residues at the "a" and "d" positions were substituted, while the replacement of the separate Leu (15th) residue had less effect. Based on the quenching of the intrinsic fluorescence of the peptides and their induced surface pressure changes of lipid monolayer, it was conjectured that the peptide ZXR-2 might insert into cell membranes from the C-terminal and to a depth of the W11 position. Accordingly, I3, I7, and L10 residues which mainly exposed in aqueous solution were more responsible for the peptide self-association on cell membranes, while L14, together with L15, might help peptide insert and anchor to cell membranes. These results are significant to elucidate the crucial roles of such Ile/Leu residues at "a" and "d" positions in peptide-peptide and peptide-membrane interactions to exert the membrane disruption activity of lytic peptides. With further understanding about the structure-activity relationship of lytic peptides, it would be helpful for designing novel anticancer lytic peptides.


Asunto(s)
Antineoplásicos/farmacología , Isoleucina/química , Leucina/química , Péptidos/farmacología , 1,2-Dipalmitoilfosfatidilcolina/análogos & derivados , 1,2-Dipalmitoilfosfatidilcolina/química , Alanina/química , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Antineoplásicos/síntesis química , Línea Celular Tumoral , Membrana Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Colesterol/química , Células HEK293 , Células HeLa , Humanos , L-Lactato Deshidrogenasa/metabolismo , Liposomas/química , Péptidos/síntesis química , Fosfatidilserinas/química , Ingeniería de Proteínas , Estructura Secundaria de Proteína , Electricidad Estática , Relación Estructura-Actividad
17.
Org Biomol Chem ; 15(26): 5535-5540, 2017 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-28632271

RESUMEN

Copper-promoted direct C-H alkoxylation of S,S-functionalized internal olefins, that is, α-oxo ketene dithioacetals, was efficiently achieved with alcohols as the alkoxylating agents, (diacetoxyiodo)benzene (PhI(OAc)2) as the oxidant, and benzoquinone (BQ) as the co-oxidant. The alkoxylated olefins were thus constructed and applied for the synthesis of alkoxylated N-heterocycles. The polarization of the olefinic carbon-carbon double bond by the electron-donating dialkylthio and electron-withdrawing α-oxo functionalities plays a crucial role in making such C-H alkoxylation reactions to occur under mild conditions. Mechanistic studies implicate a single-electron-transfer (SET) reaction pathway involved in the overall catalytic cycle.

18.
Anaerobe ; 47: 165-172, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28571698

RESUMEN

Dental caries, a highly prevalent oral disease, is primarily caused by pathogenic bacteria infection, and most of them are anaerobic. Herein, we investigated the activity of a designed antimicrobial peptide ZXR-2, and found it showed broad-spectrum activity against a variety of Gram-positive and Gram-negative oral bacteria, particularly the caries-related taxa Streptococcus mutans. Time-course killing assays indicated that ZXR-2 killed most bacterial cells within 5 min at 4 × MIC. The mechanism of ZXR-2 involved disruption of cell membranes, as observed by scanning electron microscopy. Moreover, ZXR-2 inhibited the formation of S. mutans biofilm, but showed limited hemolytic effect. Based on its potent antimicrobial activity, rapid killing, and inhibition of S. mutans biofilm formation, ZXR-2 represents a potential therapeutic for the prevention and treatment of dental caries.


Asunto(s)
Antiinfecciosos/aislamiento & purificación , Antiinfecciosos/farmacología , Péptidos Catiónicos Antimicrobianos/aislamiento & purificación , Péptidos Catiónicos Antimicrobianos/farmacología , Caries Dental/microbiología , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Antiinfecciosos/síntesis química , Péptidos Catiónicos Antimicrobianos/síntesis química , Péptidos Catiónicos Antimicrobianos/genética , Biopelículas/efectos de los fármacos , Membrana Celular/efectos de los fármacos , Membrana Celular/ultraestructura , Humanos , Pruebas de Sensibilidad Microbiana , Viabilidad Microbiana/efectos de los fármacos , Microscopía Electrónica de Rastreo
19.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 45(5): 469-476, 2016 05 25.
Artículo en Zh | MEDLINE | ID: mdl-28087906

RESUMEN

Objective: To investigate the effects and the underlying molecular mechanisms of curcumin on pulmonary artery smooth muscle cells in rat model with chronic obstructive pulmonary disease (COPD). Methods: A total of 75 male Wistar rats were randomly divided into control group (group CN), model group (group M), low-dose curcumin group (group CL), medium-dose curcumin group (group CM) and high-dose curcumin group (group CH). HE staining was used to observe the morphology of pulmonary artery. Proliferating cell nuclear antigen (PCNA), apoptosis-related protein Bcl-2 and Bax were detected by immunohistochemical staining. TUNEL kit was used to analyze the effects of curcumin on apoptosis of smooth muscle cells, and the protein expressions of SOCS-3/JAK2/STAT pathway in lung tissues were determined by western blot. Results: Right ventricular systolic pressure (RVSP) and right ventricular hypertrophy index (RVMI) in group M were significantly higher than those in group CN, group CH and group CM (all P<0.05). HE staining and TUNEL kit test showed that the number of pulmonary artery smooth muscle cells had a significant increase in group M, while the pulmonary artery tube became thin, and the smooth muscle cells shrinked in group CM and group CH. Immunohistochemistry showed that PCNA and Bcl-2 in group M were significantly higher than those in group CN (all P<0.05), while Bax expression was significantly lower than that in group CN (P<0.05). PCNA in group CM and group CH were significantly lower than that in group M (all P<0.05), while Bax expression was significantly higher than that in group M (P<0.05). Western blot showed that SOCS-3 protein was significantly decreased in group M, while the p-JAK2, p-STAT1, p-STAT3 were significantly increased (all P<0.05). Compared with group M, SOCS-3 protein in group CM and group CH were significantly increased (all P<0.05), while the p-JAK2, p-STAT3 were significantly reduced (all P<0.05). Conclusion: Curcumin could promote the apoptosis of smooth muscle cells in rats with COPD, and improve the mean pulmonary artery pressure and RVMI through stimulating SOCS-3/JAK2/STAT signaling pathway.


Asunto(s)
Apoptosis/efectos de los fármacos , Presión Arterial/efectos de los fármacos , Curcumina/farmacología , Miocitos del Músculo Liso/efectos de los fármacos , Miocitos del Músculo Liso/patología , Arteria Pulmonar/efectos de los fármacos , Arteria Pulmonar/patología , Enfermedad Pulmonar Obstructiva Crónica/patología , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Animales , Apoptosis/fisiología , Presión Arterial/fisiología , Hipertrofia Ventricular Derecha/patología , Hipertrofia Ventricular Derecha/fisiopatología , Janus Quinasa 2/efectos de los fármacos , Janus Quinasa 2/fisiología , Pulmón/química , Pulmón/efectos de los fármacos , Masculino , Antígeno Nuclear de Célula en Proliferación/efectos de los fármacos , Antígeno Nuclear de Célula en Proliferación/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/efectos de los fármacos , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Ratas , Ratas Wistar , Factores de Transcripción STAT , Proteína 3 Supresora de la Señalización de Citocinas/efectos de los fármacos , Proteína 3 Supresora de la Señalización de Citocinas/fisiología , Presión Ventricular/efectos de los fármacos , Proteína X Asociada a bcl-2/efectos de los fármacos , Proteína X Asociada a bcl-2/metabolismo
20.
Angew Chem Int Ed Engl ; 55(3): 862-75, 2016 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-26639633

RESUMEN

Transition-metal-catalyzed C-alkylation of ketones and secondary alcohols, with alcohols, avoids use of organometallic or environmentally unfriendly alkylating agents by means of borrowing hydrogen (BH) or hydrogen autotransfer (HA) activation of the alcohol substrates. Water is formed as the only by-product, thus making the BH process atom-economical and environmentally benign. Diverse homogeneous and heterogeneous transition-metal catalysts, ketones, and alcohols can be used for this transformation, thus rendering the BH process promising for replacing those procedures that use traditional alkylating agents. This Minireview summarizes the advances during the last five years in transition-metal-catalyzed BH α-alkylation of ketones, and ß-alkylation of secondary alcohols with alcohols. A discussion on the application of the BH strategy for C-C bond formation is included.

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