RESUMEN
The recurrent COVID-19 infection, despite global vaccination, highlights the need for booster doses. A heterologous booster has been suggested to enhance immunity and protection against emerging variants of concern of the SARS-CoV-2 virus. In this report, we aimed to assess the safety, and immunogenicity of COReNAPCIN, as a fourth booster dose after three doses of inactivated vaccines. METHODS: The study was conducted as a double-blind, randomized, placebo-controlled phase 1 clinical trial of the mRNA-based vaccine candidate, COReNAPCIN. The vaccine was injected as a heterologous booster in healthy Iranian adults aged 18-50 who had previously received three doses of inactivated SARS-CoV-2 vaccines. In the study, 30 participants were randomly assigned to receive either COReNAPCIN in two different doses (25 µg and 50 µg) or placebo. The vaccine candidate contained mRNA encoding the complete sequence of the pre-fusion stabilized Spike protein of SARS-CoV-2, formulated within lipid nanoparticles. The primary endpoint was safety and the secondary objective was humoral immunogenicity until 6 months post-vaccination. The cellular immunogenicity was pursued as an exploratory outcome. RESULTS: COReNAPCIN was well tolerated in vaccinated individuals in both doses with no life-threatening or other serious adverse events. The most noticeable solicited adverse events were pain at the site of injection, fatigue and myalgia. Regarding the immunogenicity, despite the seroprevalence of SARS-CoV-2 antibodies due to the vaccination history for all and previous SARS-CoV-2 infection for some participants, the recipients of 25 and 50 µg COReNAPCIN, two weeks post-vaccination, showed 6·6 and 8·1 fold increase in the level of anti-RBD, and 11·5 and 21·7 fold increase in the level of anti-spike antibody, respectively. The geometric mean virus neutralizing titers reached 10.2 fold in the 25 µg group and 8.4 fold in 50 µg group of pre-boost levels. After 6 months, the measured anti-spike antibody concentration still maintains a geometric mean fold rise of 2.8 and 6.3, comparing the baseline levels in 25 and 50 µg groups, respectively. Additionally, the significant increase in the spike-specific IFN-Ï T-cell response upon vaccination underscores the activation of cellular immunity. CONCLUSION: COReNAPCIN booster showed favorable safety, tolerability, and immunogenicity profile, supporting its further clinical development (Trial registration: IRCT20230131057293N1).
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Anticuerpos Antivirales , Vacunas contra la COVID-19 , COVID-19 , Inmunización Secundaria , SARS-CoV-2 , Humanos , Adulto , Masculino , Método Doble Ciego , Femenino , Vacunas contra la COVID-19/inmunología , Vacunas contra la COVID-19/efectos adversos , Vacunas contra la COVID-19/administración & dosificación , Irán , SARS-CoV-2/inmunología , Adulto Joven , COVID-19/prevención & control , COVID-19/inmunología , Persona de Mediana Edad , Anticuerpos Antivirales/sangre , Inmunogenicidad Vacunal , Glicoproteína de la Espiga del Coronavirus/inmunología , Anticuerpos Neutralizantes/sangre , Vacunas de ARNm , Adolescente , Estudios de SeguimientoRESUMEN
Background: Limited data exist regarding the status of long-term cardiovascular disease (CVD) outcomes of hospitalized COVID-19 patients. We aimed to examine the efficacy of early statin use after SARS-CoV-2 pneumonia and the impact of prior CVD on the incidence of cardiovascular events. Methods: A prospective cohort study was performed on hospitalized COVID-19 patients. The primary endpoint was major adverse cardiovascular events (MACE) as a composite of cardiovascular mortality, stroke, heart failure, venous thromboembolism (VTE), revascularization, and nonfatal myocardial infarction (MI). The secondary endpoints comprised MACE components, all-cause mortality, readmission for COVID-19, and impaired functional classes. Results: The mean age of the 858 participants was 55.52±13.97 years, and the median follow-up time was 13 months (11.5-15). Men comprised 63.9% of the patients. Overall, MACE occurred in 84 subjects (9.8%), and 98 patients (11.4%) received ventilation. A multivariate Cox regression model was employed to explore the association between statin use and outcomes, and the following hazard ratios were obtained: MACE (0.831 [0.529 to 0.981]; P=0.044), All-cause mortality (1.098 [0.935 to 1.294]; P=0.255), stroke (0.118 [0.029 to 0.48]; P=0.003), revascularization (0.103 [0.029 to 0.367]; P<0.0001), poor functional capacity (0.827 [0.673 to 1.018]; P=0.073), nonfatal MI (0.599 [0.257 to 1.394]; P=0.234), VTE (0.376 [0.119 to 1.190]; P=0.096), and decompensated heart failure (0.137 [0.040 to 0.472]; P=0.002). Prior CVD predicted MACE (2.953 [1.393 to 6.271]; P=0.005), all-cause death (1.170 [0.960 to 1.412]; P=0.102), and VTE (2.770 [0.957 to 8.955]; P=0.051). Conclusion: Previous CVD is a robust predictor of long-term MACE and VTE. Early statin use might decrease the incidence rates of MACE, ischemic stroke, revascularization, and readmission for heart failure.
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Coronavirus disease-19 (COVID-19) vaccines are massively administered globally and some adverse events, such as myocarditis, are being reported. Most of the reported cases of post-vaccination myocarditis have occurred following mRNA vaccinations. However, there have also been recent reports of myocarditis following adenovirus vector vaccinations. We present a case of a 32-year-old female patient who developed myocarditis following the administration of the first dose of the AstraZeneca vaccine. The patient developed inappropriate exertional tachycardia and exertional dyspnea from Day 3 and was diagnosed with myocarditis by subsequent echocardiography about 3 months later. We are unable to confirm a direct association between myocarditis and AstraZeneca vaccination. However, we would like to increase awareness regarding the possibility of developing myocarditis following AstraZeneca vaccination.
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Drug similarity studies are driven by the hypothesis that similar drugs should display similar therapeutic actions and thus can potentially treat a similar constellation of diseases. Drug-drug similarity has been derived by variety of direct and indirect sources of evidence and frequently shown high predictive power in discovering validated repositioning candidates as well as other in-silico drug development applications. Yet, existing resources either have limited coverage or rely on an individual source of evidence, overlooking the wealth and diversity of drug-related data sources. Hence, there has been an unmet need for a comprehensive resource integrating diverse drug-related information to derive multi-evidenced drug-drug similarities. We addressed this resource gap by compiling heterogenous information for an exhaustive set of small-molecule drugs (total of 10 367 in the current version) and systematically integrated multiple sources of evidence to derive a multi-modal drug-drug similarity network. The resulting database, 'DrugSimDB' currently includes 238 635 drug pairs with significant aggregated similarity, complemented with an interactive user-friendly web interface (http://vafaeelab.com/drugSimDB.html), which not only enables database ease of access, search, filtration and export, but also provides a variety of complementary information on queried drugs and interactions. The integration approach can flexibly incorporate further drug information into the similarity network, providing an easily extendable platform. The database compilation and construction source-code has been well-documented and semi-automated for any-time upgrade to account for new drugs and up-to-date drug information.
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Algoritmos , Simulación por Computador , Bases de Datos Farmacéuticas , Reposicionamiento de Medicamentos , Preparaciones Farmacéuticas , Programas Informáticos , HumanosRESUMEN
Microtubule affinity-regulating kinase 4 (MARK4) is a Ser/Thr protein kinase, best known for its role in phosphorylating microtubule associated proteins, causing their detachment from microtubules. In the current study, the non-phosphorylated conformation of the activation loop was modeled in a structure representing the enzymatically inactive form of this protein, and its dynamics were evaluated through a 100 ns initial all-atom simulation, which was prolonged by another 2 µs. Although the activation loop was folding on itself and was leaning toward ATP site in the initial modeled structure, soon after the initiating the simulation, this loop stretched away from the ATP binding site and stably settled in its new position for the rest of simulation time. A network of hydrogen bonds, mainly between the activation segment residues, αC-helix and the catalytic loop reinforced this conformation. Interestingly, several features of active kinase conformation such as formation of R-spine, Glu106-Lys88 salt-bridge, and DFG-In motif were observed during a considerable number of trajectory frames. However, they were not sustainably established during the simulation time, except for the DFG-In motif. Consequently, this study introduces a stable conformation of the non-phosphorylated form of MARK4 protein with a partially stretched activation loop conformation as well as partial formation of R-spine, closely resembling the active kinase.
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Simulación de Dinámica Molecular , Conformación Proteica , Proteínas Serina-Treonina Quinasas/química , Sitios de Unión , Humanos , Enlace de Hidrógeno , Fosforilación , Unión Proteica , Proteínas Serina-Treonina Quinasas/metabolismoRESUMEN
The mammalian kynurenine aminotransferase (KAT) enzymes are a family of related isoforms that are pyridoxal 5'-phosphate-dependent, responsible for the irreversible transamination of kynurenine to kynurenic acid. Kynurenic acid is implicated in human diseases such as schizophrenia where it is found in elevated levels and consequently KAT-II, as the isoform predominantly responsible for kynurenic acid production in the brain, has been targeted for the development of specific inhibitors. One class of compounds that have also shown inhibitory activity towards the KAT enzymes are estrogens and their sulfate esters. Estradiol disulfate in particular is very strongly inhibitory and it appears that the 17-sulfate makes a significant contribution to its potency. The work here demonstrates that the effect of this moiety can be mirrored in existing KAT-II inhibitors, from the development of two novel inhibitors, JN-01 and JN-02. Both inhibitors were based on NS-1502 (IC50: 315 µM), but the deliberate placement of a sulfonamide group significantly improved the potency of JN-01 (IC50: 73.8 µM) and JN-02 (IC50: 112.8 µM) in comparison to the parent compound. This 3-4 fold increase in potency shows the potential of these moieties to be accommodated in the KAT-II active site and the effect they can have on improving inhibitors, and the environments in the KAT-II have been suitably modelled using docking calculations.
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Inhibidores Enzimáticos/síntesis química , Ésteres/síntesis química , Estradiol/análogos & derivados , Sulfatos/síntesis química , Transaminasas/antagonistas & inhibidores , Dominio Catalítico , Relación Dosis-Respuesta a Droga , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/metabolismo , Inhibidores Enzimáticos/farmacología , Ésteres/química , Ésteres/metabolismo , Ésteres/farmacología , Estradiol/química , Estradiol/farmacología , Ácido Quinurénico/química , Ácido Quinurénico/metabolismo , Quinurenina/química , Quinurenina/metabolismo , Modelos Moleculares , Simulación del Acoplamiento Molecular , Imitación Molecular , Sulfatos/química , Sulfatos/metabolismo , Sulfatos/farmacología , Transaminasas/química , Transaminasas/metabolismoRESUMEN
Kynurenine aminotransferase-II (KAT-II) is a pyridoxal 5'-phosphate (PLP)-dependent enzyme that acts in the tryptophan metabolic pathway by catalyzing the transamination of kynurenine into kynurenic acid (KYNA). It is one of four isoforms in the KAT family, of which it is the primary homologue responsible for KYNA production in the mammalian brain. KAT-II is targeted for inhibition as KYNA is implicated in diseases such as schizophrenia, where it is found in elevated concentrations. Previously, many different approaches have been taken to develop KAT-II inhibitors, and herein fragment-based drug design (FBDD) approaches have been exploited to provide further lead compounds that can be designed into novel inhibitors. Surface plasmon resonance (SPR) was used to screen a fragment library containing 1000 compounds, of which 41 hits were identified. These hits were further evaluated with SPR, and 18 were selected for inhibition studies. From these hits, two fragments, F6037-0164 and F0037-7280, were pursued and determined to have an IC50 of 524.5 (± 25.6) µM and 115.2 (± 4.5) µM, respectively. This strategy shows the viability of using FBDD in gleaning knowledge about KAT-II inhibition and generating leads for the production of KAT-II inhibitors.
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Quinurenina/metabolismo , Transaminasas/metabolismo , Diseño de Fármacos , Inhibidores Enzimáticos/farmacología , Humanos , Ácido Quinurénico/metabolismo , Fosfato de Piridoxal/metabolismo , Bibliotecas de Moléculas Pequeñas/farmacología , Resonancia por Plasmón de Superficie/métodosRESUMEN
BACKGROUND: Non-atherosclerotic spontaneous coronary artery dissection (SCAD) is a rare disease that predominantly affects women. It presents with acute chest pain, ventricular arrhythmias, and even sudden cardiac death. CASE SUMMARY: A 33-year-old man presented to emergency department with fatigue and cold sweat. He had no complaint of chest pain at the time of admission. He experienced a retrosternal chest pain 2 days ago after lifting a 30 pounds weight in the gym. Para-clinic results such as coronary computed tomography angiography and electrocardiogram were normal. However, coronary angiography showed multiple coronary dissections. We followed the patient for 4 months. He was asymptomatic except for one episode of chest pain during Tehran earthquake, while he was carrying his child to escape the room. Follow-up myocardial perfusion scan was negative for ischaemia. DISCUSSION: Stressors such as intense exercise, emotional stress, and Valsalva manoeuvre may cause SCAD in otherwise healthy patient. As in our case, lifting heavy weights was the most likely reason for SCAD. Stable patients without ongoing chest pain will be followed conservatively.
RESUMEN
The kynurenine aminotransferase (KAT) enzymes are pyridoxal 5'-phosphate-dependent homodimers that catalyse the irreversible transamination of kynurenine into kynurenic acid (KYNA) in the tryptophan metabolic pathway. Kynurenic acid is implicated in cognitive diseases such as schizophrenia, and several inhibitors have been reported that selectively target KAT-II as it is primarily responsible for kynurenic acid production in the human brain. Not only is schizophrenia a sexually dimorphic condition, but women that have schizophrenia have reduced estrogen levels in their serum. Estrogens are also known to interact in the kynurenine pathway therefore exploring these interactions can yield a better understanding of the condition and improve approaches in ameliorating its effects. Enzyme inhibitory assays and binding studies showed that estradiol disulfate is a strong inhibitor of KAT-I and KAT-II (IC50: 291.5 µM and 26.3 µM, respectively), with estradiol, estradiol 3-sulfate and estrone sulfate being much weaker (IC50 > 2 mM). Therefore it is possible that estrogen levels can dictate the balance of kynurenic acid in the brain. Inhibition assay results and modelling suggests that the 17-sulfate moiety in estradiol disulfate is very important in improving its potency as an inhibitor, increasing the inhibition by approximately 10-100 fold compared to estradiol.
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Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Estrógenos/química , Estrógenos/farmacología , Transaminasas/antagonistas & inhibidores , Dominio Catalítico , Diseño de Fármacos , Humanos , Isoenzimas/antagonistas & inhibidores , Isoenzimas/química , Modelos Moleculares , Transaminasas/químicaRESUMEN
Investigation of the single plant source bee glue type originating from Southern Australia resulted in the isolation and structure elucidation of major serrulatane diterpenes, novel 7,8,18-trihydroxyserrulat-14-ene (1), along with its oxidized product, 5,18-epoxyserrulat-14-en-7,8-dione (3) and known (18RS)-5,18-epoxyserrulat-14-en-8,18-diol (2). Exploration into the botanical origin revealed Myoporum insulare R. Br, as the plant source of the bee glue materials. This discovery was made through comparative analysis of the myoporum bee glue samples collected from the beehives, analyses of plant resinous exudate, and resin carried on the hind legs of bees foraging for bee glue.
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Diterpenos/química , Plantas/química , Própolis/química , Resinas de Plantas/química , Animales , Abejas , Estructura Molecular , Myoporum/química , Scrophulariaceae/químicaRESUMEN
Propolis is one of the complex, but valuable, bio-sources for discovering therapeutic compounds. Diterpenes are organic compounds composed of four isoprene units and are known for their biological and pharmacological characteristics, such as antibacterial, anticancer, and anti-inflammatory activities. Recently, advancements have been made in the development of antibacterial and anticancer leads from propolis-isolated diterpenes, and scrutiny of these compounds is being pursued. Thus, this review covers the progress in this arena, with a focus on the chemistry and biological activities of propolis diterpenes. It is anticipated that important information, in a comprehensive and concise manner, will be delivered here for better understanding of natural product drug discovery research.
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Diterpenos/farmacología , Própolis/farmacología , Animales , Antineoplásicos/química , Antineoplásicos/farmacología , Abejas , Diterpenos/química , Descubrimiento de Drogas , Própolis/químicaRESUMEN
Human Group IIA phospholipase A2 (hGIIA) promotes inflammation in immune-mediated pathologies by regulating the arachidonic acid pathway through both catalysis-dependent and -independent mechanisms. The hGIIA crystal structure, both alone and inhibitor-bound, together with structures of closely related snake-venom-derived secreted phospholipase enzymes has been well described. However, differentiation of biological and nonbiological contacts and the relevance of structures determined from snake venom enzymes to human enzymes are not clear. We employed molecular dynamics (MD) and docking approaches to understand the binding of inhibitors that selectively or nonselectively block the catalysis-independent mechanism of hGIIA. Our results indicate that hGIIA behaves as a monomer in the solution environment rather than a dimer arrangement that is in the asymmetric unit of some crystal structures. The binding mode of a nonselective inhibitor, KH064, was validated by a combination of the experimental electron density and MD simulations. The binding mode of the selective pentapeptide inhibitor FLSYK to hGIIA was stipulated to be different to that of the snake venom phospholipases A2 of Daboia russelli pulchella (svPLA2 ). Our data suggest that the application of MD approaches to crystal structure data is beneficial in evaluating the robustness of conclusions drawn based on crystal structure data alone. Proteins 2017; 85:827-842. © 2016 Wiley Periodicals, Inc.
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Electrones , Fosfolipasas A2 Grupo II/antagonistas & inhibidores , Simulación de Dinámica Molecular , Oligopéptidos/química , Ácidos Pentanoicos/química , Inhibidores de Fosfolipasa A2/química , Secuencias de Aminoácidos , Animales , Sitios de Unión , Fosfolipasas A2 Grupo II/química , Humanos , Simulación del Acoplamiento Molecular , Fosfolipasas A2/química , Unión Proteica , Conformación Proteica en Hélice alfa , Conformación Proteica en Lámina beta , Dominios y Motivos de Interacción de Proteínas , Venenos de Víboras/química , Viperidae/metabolismoRESUMEN
Pillar[n]arenes are a new family of nanocapsules that have shown application in a number of areas, but because of their poor water solubility their biomedical applications are limited. Recently, a method of synthesizing water-soluble pillar[n]arenes was developed. In this study, carboxylated pillar[n]arenes (WP[n], n = 6 or 7) have been examined for their ability to form host-guest complexes with compounds relevant to drug delivery and biodiagnostic applications. Both pillar[n]arenes form host-guest complexes with memantine, chlorhexidine hydrochloride, and proflavine by 1H nuclear magnetic resonance and modeling. Binding is stabilized by hydrophobic effects within the cavities, and hydrogen bonding and electrostatic interactions at the portals. Encapsulation within WP[6] results in the complete and efficient quenching of proflavine fluorescence, giving rise to "on" and "off" states that have potential in biodiagnostics. The toxicity of the pillar[n]arenes was examined using in vitro growth assays with the OVCAR-3 and HEK293 cell lines. The pillar[n]arenes are relatively nontoxic to cells except at high doses and after prolonged continuous exposure. Overall, the results show that there could be a potentially large range of medical applications for carboxylated pillar[n]arene nanocapsules.
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Sustancias Macromoleculares/metabolismo , Modelos Moleculares , Preparaciones Farmacéuticas/metabolismo , Compuestos de Amonio Cuaternario/metabolismo , Células HEK293 , Humanos , Sustancias Macromoleculares/química , Memantina/metabolismo , Preparaciones Farmacéuticas/química , Proflavina/química , Proflavina/metabolismo , Compuestos de Amonio Cuaternario/químicaRESUMEN
Abnormal levels of kynurenic acid (KYNA) in the human brain are believed to be connected to several central nervous system (CNS) diseases, therefore compounds which affect the production of this crucial metabolite are of interest in CNS drug development. The majority of KYNA production is accounted for by kynurenine aminotransferase-2 (KAT-2) in the mammalian brain; hence this enzyme is one of the most interesting targets with which to modulate KYNA levels. Recently developed human KAT-2 inhibitors with high potencies are known to irreversibly bind to the enzyme cofactor, pyridoxal-5'-phosphate (PLP), which may lead to severe side effects due to the abundance of PLP-dependent enzymes. In this study, we report a reversible and competitive inhibitor of KAT-2. Its inhibitory activities were examined using HPLC and surface plasmon resonance (SPR) and compare favorably with other recently reported KAT-2 inhibitors. Our inhibitor, NS-1502, demonstrates suitable inhibitory activity, almost 10 times more potent than the known reversible KAT-2, (S)-ESBA.
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Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Transaminasas/antagonistas & inhibidores , Transaminasas/química , Catálisis , Trastornos del Conocimiento/tratamiento farmacológico , Relación Dosis-Respuesta a Droga , Diseño de Fármacos , Descubrimiento de Drogas , Activación Enzimática/efectos de los fármacos , Humanos , Espectroscopía de Resonancia Magnética , Estructura Molecular , Enfermedades Neurodegenerativas/tratamiento farmacológico , Unión Proteica , Relación Estructura-ActividadRESUMEN
Kynurenine aminotransferase isozymes (KATs 1-4) are members of the pyridoxal-5'-phosphate (PLP)-dependent enzyme family, which catalyse the permanent conversion of l-kynurenine (l-KYN) to kynurenic acid (KYNA), a known neuroactive agent. As KATs are found in the mammalian brain and have key roles in the kynurenine pathway, involved in different categories of central nervous system (CNS) diseases, the KATs are prominent targets in the quest to treat neurodegenerative and cognitive impairment disorders. Recent studies suggest that inhibiting these enzymes would produce effects beneficial to patients with these conditions, as abnormally high levels of KYNA are observed. KAT-1 and KAT-3 share the highest sequence similarity of the isozymes in this family, and their active site pockets are also similar. Importantly, KAT-2 has the major role of kynurenic acid production (70%) in the human brain, and it is considered therefore that suitable inhibition of this isozyme would be most effective in managing major aspects of CNS diseases. Human KAT-2 inhibitors have been developed, but the most potent of them, chosen for further investigations, did not proceed in clinical studies due to the cross toxicity caused by their irreversible interaction with PLP, the required cofactor of the KAT isozymes, and any other PLP-dependent enzymes. As a consequence of the possibility of extensive undesirable adverse effects, it is also important to pursue KAT inhibitors that reversibly inhibit KATs and to include a strategy that seeks compounds likely to achieve substantial interaction with regions of the active site other than the PLP. The main purpose of this treatise is to review the recent developments with the inhibitors of KAT isozymes. This treatise also includes analyses of their crystallographic structures in complex with this enzyme family, which provides further insight for researchers in this and related studies.
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Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Transaminasas/antagonistas & inhibidores , Transaminasas/química , Animales , Sitios de Unión , Humanos , Modelos Moleculares , Conformación Molecular , Estructura Molecular , Unión Proteica , Relación Estructura-Actividad CuantitativaRESUMEN
Kynurenine aminotransferase II (KAT-II) is a 47 kDa pyridoxal phosphate (PLP)-dependent enzyme, active as a homodimer, which catalyses the transamination of the amino acids kynurenine (KYN) and 3-hydroxykynurenine (3-HK) in the tryptophan pathway, and is responsible for producing metabolites that lead to kynurenic acid (KYNA), which is implicated in several neurological diseases such as schizophrenia. In order to fully describe the role of KAT-II in the pathobiology of schizophrenia and other brain disorders, the crystal structure of full-length PLP-form hKAT-II was determined at 1.83 Å resolution, the highest available. The electron density of the active site reveals an aldimine linkage between PLP and Lys263, as well as the active site residues, which characterize the fold-type I PLP-dependent enzymes.
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Transaminasas/química , Sitios de Unión , Dominio Catalítico , Cristalografía por Rayos X , Humanos , Enlace de Hidrógeno , Estructura Terciaria de Proteína , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/química , Proteínas Recombinantes/aislamiento & purificación , Transaminasas/genética , Transaminasas/metabolismoRESUMEN
Kynurenine aminotransferase (KAT) is a pyridoxal-5'-phosphate (PLP) dependent enzyme that catalyses kynurenine (KYN) to kynurenic acid (KYNA), a neuroactive product in the tryptophan metabolic pathway. Evidence suggests that abnormal levels of KYNA are involved in many neurodegenerative diseases such as Parkinson's disease, Huntington's disease, Alzheimer's disease and schizophrenia. Reducing KYNA production through inhibiting kynurenine aminotransferase 2 (KAT2) would be a promising approach to understanding and treating the related neurological and mental disorders. In this study we used an optimized codon sequence to overexpress histidine-tagged human KAT2 (hKAT2) using an Escherichia coli expression system. After a single step of Ni-NTA based purification the purified protein (>95%) was confirmed to be active by an HPLC based activity assay and was crystallized using the hanging-drop vapour diffusion method. The crystal system represents a novel space group, and a complete X-ray diffraction data set was collected to 1.83 Å resolution, and higher resolution data than for any reported native human KAT2 structure. The optimised method of protein production provides a fast and reliable technique to generate large quantities of active human KAT2 suitable for future small-molecule lead compound screening and structural design work.
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Enfermedades Neurodegenerativas/terapia , Transaminasas/química , Transaminasas/genética , Cromatografía Líquida de Alta Presión , Codón/genética , Escherichia coli/genética , Regulación Enzimológica de la Expresión Génica , Humanos , Ácido Quinurénico/química , Ácido Quinurénico/metabolismo , Quinurenina/química , Quinurenina/metabolismo , Enfermedades Neurodegenerativas/patología , Conformación Proteica , Transaminasas/aislamiento & purificación , Transaminasas/uso terapéutico , Difracción de Rayos XRESUMEN
BACKGROUND: Adhesion molecules play an important role in the development and progression of coronary atherosclerosis. The aim of this study was comparing the effect of Cratagol herbal tablet, aerobic exercise and their combination on the serum levels of Intercellular adhesion molecule (ICAM)-1 and E-Selectin in patients with stable angina pectoris. METHODS: Eighty stable angina pectoris patients aged between 45 and 65 years, were randomly divided into four groups including three experimental groups and one control group: aerobic exercise (E), Crataegus oxyacantha extract (S), aerobic exercise and Crataegus oxyacantha extract (S+E), and control (C). Blood sampling was taken 24 h before and after 12 weeks of aerobic exercise and Crataegus oxyacantha extract consumption. The results of serum levels of ICAM-1 and E-selectin were compared. RESULTS: Intergroup comparison of the data revealed a significant reduction (P <0.01) in serum levels of ICAM-1 and E-selectin in experimental groups. Analysis of data showed that the serum levels of ICAM-1 had significant difference when group S+E was compared with groups S and C, but not group E (P = 0.021, P = 0.000 and P = 0.068, respectively). Also the difference between the levels of E-selectin was significant comparing S+E and S but not E with group C (P = 0.021, P = 0.000 and P = 0.052, respectively). CONCLUSIONS: Twelve weeks effects of aerobic exercise and Crataegus oxyacantha extract consuming is an effective complementary strategy to significantly lower the risk of atherosclerosis and heart problems.
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Angina Estable/terapia , Aterosclerosis/prevención & control , Selectina E/sangre , Molécula 1 de Adhesión Intercelular/sangre , Extractos Vegetales/administración & dosificación , Angina Estable/sangre , Terapia Combinada , Crataegus/química , Ejercicio Físico , Femenino , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Masculino , Persona de Mediana Edad , Extractos Vegetales/farmacología , Distribución Aleatoria , Comprimidos , Resultado del TratamientoRESUMEN
Schizophrenia is a complex neuropsychiatric disorder with limited treatment options and highly debilitating symptoms, leading to poor personal, social, and occupational outcomes for an afflicted individual. Our current understanding of schizophrenia suggests that dopaminergic and glutamatergic systems have a significant role in the pathogenesis of the disease. Kynurenic acid, an endogenous glutamate antagonist, is found in elevated concentrations in the prefrontal cortex and cerebrospinal fluid of patients with schizophrenia, and this affects neurotransmitter release in a similar manner to previously observed psychotomimetic agents, such as phencyclidine, underlining the molecular basis to its link in schizophrenia pathophysiology. Kynurenic acid is a breakdown product of tryptophan degradation, through a transamination process mediated by kynurenine aminotransferase (KAT) enzymes. There are four KAT homologues reported, all of which are pyridoxal 5'- phosphate-dependent enzymes. All four KAT isoforms have been analysed structurally and biochemically, however the most extensive research is on KAT-I and KAT-II. These two enzymes have been targeted in structure-based drug design as a means of normalising raised kynurenic acid levels. The most potent KAT-I inhibitors and KAT-II inhibitors include phenylhydrazone hexanoic acid derivatives and a pyrazole series of compounds, respectively. KAT inhibitors have been shown to be effective in reducing kynurenic acid production, with accompanying changes in neurotransmitter release and pro-cognitive effects seen in animal studies. This review will discuss the characteristics pertaining to the different KAT isoforms, and will highlight the development of significant KAT inhibitors. KAT inhibitors have great potential for therapeutic application and represent a novel way in treating schizophrenia.
Asunto(s)
Esquizofrenia/metabolismo , Transaminasas/metabolismo , Animales , Humanos , Esquizofrenia/tratamiento farmacológico , Transaminasas/antagonistas & inhibidoresRESUMEN
AIM: The aim of this study was to examine and evaluate crucial variables in essential oils extraction process from Lavandula hybrida through static-dynamic and semi-continuous techniques using response surface method. MATERIALS AND METHODS: Essential oil components were extracted from Lavandula hybrida (Lavandin) flowers using supercritical carbon dioxide via static-dynamic steps (SDS) procedure, and semi-continuous (SC) technique. RESULTS: Using response surface method the optimum extraction yield (4.768%) was obtained via SDS at 108.7 bar, 48.5°C, 120 min (static: 8×15), 24 min (dynamic: 8×3 min) in contrast to the 4.620% extraction yield for the SC at 111.6 bar, 49.2°C, 14 min (static), 121.1 min (dynamic). CONCLUSION: The results indicated that a substantial reduction (81.56%) solvent usage (kg CO2/g oil) is observed in the SDS method versus the conventional SC method.