RESUMEN
Trehalose, a versatile disaccharide renowned for its unique physical and chemical properties, finds extensive application in the food, pharmaceutical, and cosmetic industries. While conventional extraction methods face challenges, enzymatic conversion offers a promising avenue for the industrial production of trehalose. This study delves into a novel synthetic approach utilizing a recombinant enzyme, merging the thermostable trehalose synthase domain from Thermus thermophiles with a cellulose binding domain. Immobilization of this enzyme on cellulose matrices enhances stability and facilitates product purification, opening avenues for efficient enzymatic synthesis. Notably, the engineered enzyme demonstrates additional activity, converting sucrose into trehalulose. This dual functionality, combined with immobilization strategies, holds immense potential for scalable and cost-effective production of trehalose and trehalulose, offering promising prospects in various industrial and biomedical applications.
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Trehalose synthase (TreS) catalyzes the reversible interconversion of maltose to trehalose, playing a vital role in trehalose production. Understanding the catalytic mechanism of TreS is crucial for optimizing the enzyme activity and enhancing its suitability for industrial applications. Here, we report the crystal structures of both the wild type and the E324D mutant of Deinococcus radiodurans trehalose synthase in complex with the trehalose analogue, validoxylamine A. By employing structure-guided mutagenesis, we identified N253, E320, and E324 as crucial residues within the +1 subsite for isomerase activity. Based on these complex structures, we propose the catalytic mechanism underlying the reversible interconversion of maltose to trehalose. These findings significantly advance our comprehension of the reaction mechanism of TreS.
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Proteínas Bacterianas , Deinococcus , Glucosiltransferasas , Maltosa , Trehalosa , Glucosiltransferasas/genética , Glucosiltransferasas/química , Glucosiltransferasas/metabolismo , Deinococcus/enzimología , Deinococcus/genética , Deinococcus/química , Trehalosa/metabolismo , Trehalosa/química , Maltosa/metabolismo , Maltosa/química , Proteínas Bacterianas/genética , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , MutaciónRESUMEN
Herbs themselves and various herbal medicines are great resources for discovering therapeutic drugs for various diseases, including Alzheimer's disease (AD), one of the common neurodegenerative diseases. Utilizing mouse primary cortical neurons and DiBAC4(3), a voltage-sensitive indicator, we have set up a drug screening system and identified an herbal extraction compound, paeonol, obtained from Paeonia lactiflora; this compound is able to ameliorate the abnormal depolarization induced by Aß42 oligomers. Our aim was to further find effective paeonol derivatives since paeonol has been previously studied. 6'-Methyl paeonol, one of the six paeonol derivatives surveyed, is able to inhibit the abnormal depolarization induced by Aß oligomers. Furthermore, 6'-methyl paeonol is able to alleviate the NMDA- and AMPA-induced depolarization. When a molecular mechanism was investigated, 6'-methyl paeonol was found to reverse the Aß-induced increase in ERK phosphorylation. At the animal level, mice injected with 6'-methyl paeonol showed little change in their basic physical parameters compared to the control mice. 6'-Methyl paeonol was able to ameliorate the impairment of memory and learning behavior in J20 mice, an AD mouse model, as measured by the Morris water maze. Thus, paeonol derivatives could provide a structural foundation for developing and designing an effective compound with promising clinical benefits.
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Enfermedad de Alzheimer , Ratones , Animales , Enfermedad de Alzheimer/tratamiento farmacológico , Neuronas , Acetofenonas/farmacología , Acetofenonas/uso terapéutico , Modelos Animales de Enfermedad , Péptidos beta-Amiloides/toxicidad , Aprendizaje por LaberintoRESUMEN
Dengue fever is an acute febrile disease caused by dengue virus (DENV) infection. Over the past 60 years, DENV has spread throughout tropical regions and currently affects more than 50% of the world's population; however, there are as of yet no effective anti-DENV drugs for clinical treatment. A number of research teams have investigated derivatives of glycolipids as possible agents for the inhibition of DENV. Our objective in this research was to study the antiviral effects of trehalose 6-caprate (TMC), trehalose 6-monolaurate (TML), and trehalose 6-monooleate (TMO), based on reports that the corresponding glycosyl, trehalose, reduces the transmission of Zika virus (ZIKV). We also sought to elucidate the molecular mechanisms underlying inhibition using the RNA isolation and reverse transcription-quantitative polymerase chain reaction, western blot analysis, median tissue culture infectious dose (TCID50 ) assay, and immunofluorescence assay and immunochemistry staining, in vitro. This is the first study to demonstrate the TML-induced inhibition of DENV serotype 2 (DENV-2) in a dose-dependent manner. The inhibitory effects of TML in the pretreated, cotreated, and full-treated groups were confirmed using time of addition assays. We determined that TML restricted viral binding, entry, replication, and release. We also confirmed the efficacy of TML against three clinical isolates of DENV serotypes 1, 3, and 4 (DENV-1, DENV-3, and DENV-4). The findings obtained in this study identify TML as a promising candidate for the development of drugs to treat DENV infection.
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Virus del Dengue , Dengue , Infección por el Virus Zika , Virus Zika , Humanos , Virus del Dengue/genética , Dengue/tratamiento farmacológico , Dengue/epidemiología , Virus Zika/genética , Infección por el Virus Zika/epidemiología , Trehalosa/farmacología , Trehalosa/uso terapéuticoRESUMEN
Ceramides, structural components of the cell, are known to play a range of roles in glucose metabolism and apoptosis. C16-ceramide, an abundant molecular species of endogenous ceramide, has not had its influence on learning and memory explored. We administered C16-ceramide to mice immediately after weaning and examined the learning and memory behavior of these mice during adulthood. Mice given C16-ceramide early in life showed improved adult learning/short-term memory behavior without affecting their glucose metabolism. Looking for a plausible mechanism for this, we found that calcium influx, CaMKII/CREB, and the Erk-relevant signaling transduction are increased after C16-ceramide stimulation in primary neurons in vitro. Possible downstream epigenetic molecular events, such as H3K4 methylation and Egr-1 abundance, were also found to be upregulated. Utilizing J20 mice, an Alzheimer disease mice model in which mice were injected after weaning with C16-ceramide, we found that these mice also show improved learning and short-term memory behavior when assessed by the Morris water maze test. Taken together, giving C16-ceramide early in life would seem to benefit learning and short-term memory behavior during adulthood.
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Glycogen synthase kinase-3ß (GSK-3ß) is an important serine/threonine kinase that implicates in multiple cellular processes and links with the neurodegenerative diseases including Alzheimer's disease (AD). In this study, structure-based virtual screening was performed to search database for compounds targeting GSK-3ß from Enamine's screening collection. Of the top-ranked compounds, 7 primary hits underwent a luminescent kinase assay and a cell assay using human neuroblastoma SH-SY5Y cells expressing Tau repeat domain (TauRD) with pro-aggregant mutation ΔK280. In the kinase assay for these 7 compounds, residual GSK-3ß activities ranged from 36.1% to 90.0% were detected at the IC50 of SB-216763. In the cell assay, only compounds VB-030 and VB-037 reduced Tau aggregation in SH-SY5Y cells expressing ΔK280 TauRD-DsRed folding reporter. In SH-SY5Y cells expressing ΔK280 TauRD, neither VB-030 nor VB-037 increased expression of GSK-3α Ser21 or GSK-3ß Ser9. Among extracellular signal-regulated kinase (ERK), AKT serine/threonine kinase 1 (AKT), mitogen-activated protein kinase 14 (P38) and mitogen-activated protein kinase 8 (JNK) which modulate Tau phosphorylation, VB-037 attenuated active phosphorylation of P38 Thr180/Tyr182, whereas VB-030 had no effect on the phosphorylation status of ERK, AKT, P38 or JNK. However, both VB-030 and VB-037 reduced endogenous Tau phosphorylation at Ser202, Thr231, Ser396 and Ser404 in neuronally differentiated SH-SY5Y expressing ΔK280 TauRD. In addition, VB-030 and VB-037 further improved neuronal survival and/or neurite length and branch in mouse hippocampal primary culture under Tau cytotoxicity. Overall, through inhibiting GSK-3ß kinase activity and/or p-P38 (Thr180/Tyr182), both compounds may serve as promising candidates to reduce Tau aggregation/cytotoxicity for AD treatment.
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(Background) The coronavirus disease 2019 (COVID-19) that is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) carries high infectivity and mortality. Efficient intervention strategies are urgently needed. Avian immunoglobulin Y (IgY) showed efficacy against viral infection whereas the in vivo efficacy remains unclear. (Methods) We immunized laying hens with S1, S1 receptor-binding domain (S1-RBD), or S2 subunits of the SARS-CoV-2 spike (S) protein. After immunization, IgYs were collected and extracted from the egg yolks. The neutralization potential of IgYs was examined by the plaque reduction neutralization test (PRNT). The bioutility of IgYs was examined in Syrian hamsters in vivo. (Results) IgYs exhibited typical banding patterns in SDS-PAGE and Western blot and were immunoreactive against S1, S1-RBD, and S2 subunits. The plaque reduction neutralization test (PRNT) showed that all purified IgYs potently neutralized different SARS-CoV-2 strains in vitro. In Syrian hamsters, the combination of IgYs for S1-RBD and S2 subunits administered before or after SARS-CoV-2 infection effectively restored body weight loss and reduced intrapulmonary lesions and the amount of immunoreactive N protein-positive cells, which were caused by SARS-CoV-2 infection. (Conclusions) Collectively, IgYs specific for S protein subunits effectively neutralized SARS-CoV-2 in vitro and in vivo and may serve as prophylactic or therapeutic antibodies in the prevention or treatment of COVID-19.
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Lactulose, as a prebiotic, can be utilized by human gut microbiota and stimulate their growth. Although microbiota modulation has become an emerging approach to manage many diseases and can be achieved by the administration of prebiotics, fewer investigations have been carried out on the therapeutic mechanism of lactulose. Two trehalose analogs, lactulose and melibiose, were identified as having a neuroprotective effect in polyglutamine and Parkinson disease models. In this study, we examined lactulose and melibiose in a mouse primary hippocampal neuronal culture under the toxicity of oligomeric Aß25-35. Lactulose was further tested in vivo because its effective concentration is lower than that of melibiose. Lactulose and trehalose were applied individually to mice before a bilateral intrahippocampal CA1 injection of oligomeric Aß25-35. The administration of lactulose and trehalose attenuated the short-term memory and the learning retrieval of Alzheimer's disease (AD) mice. From a pathological analysis, we found that the pretreatment of lactulose and trehalose decreased neuroinflammation and increased the levels of the autophagic pathways. These results suggest that the neuroprotective effects of both lactulose and trehalose are achieved through anti-inflammation and autophagy. In addition, lactulose was better than trehalose in the enhancement of the synaptic protein expression level in AD mice. Therefore, lactulose could potentially be developed into a preventive and/or therapeutic disaccharide for AD.
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Enfermedad de Alzheimer , Autofagia Mediada por Chaperones , Fármacos Neuroprotectores , Enfermedad de Alzheimer/tratamiento farmacológico , Animales , Autofagia , Cognición , Modelos Animales de Enfermedad , Lactulosa , Macroautofagia , Ratones , Fármacos Neuroprotectores/farmacología , PrebióticosRESUMEN
Many protein aggregation diseases (PAD) affect the nervous system. Deposits of aggregated disease-specific proteins are found within or around the neuronal cells of neurodegenerative diseases. Although the main protein component is disease-specific, oligomeric aggregates are presumed to be the key agents causing the neurotoxicity. Evidence has shown that protein aggregates cause a chronic inflammatory reaction in the brain, resulting in neurodegeneration. Therefore, strategies targeting anti-inflammation could be beneficial to the therapeutics of PAD. PHA-767491 was originally identified as an inhibitor of CDC7/CDK9 and was found to reduce TDP-43 phosphorylation and prevent neurodegeneration in TDP-43 transgenic animals. We recently identified PHA-767491 as a GSK-3ß inhibitor. In this study, we established mouse hippocampal primary culture with tau-hyperphosphorylation through the activation of GSK-3ß using Wortmannin and GF109203X. We found that PHA-767491 significantly improved the neurite outgrowth of hippocampal primary neurons against the neurotoxicity induced by GSK-3ß. We further showed that PHA-767491 had neuroprotective ability in hippocampal primary culture under oligomeric Aß treatment. In addition, PHA-767491 attenuated the neuroinflammation in mouse cerebellar slice culture with human TBP-109Q agitation. Further study of SCA17 transgenic mice carrying human TBP-109Q showed that PHA-767491 ameliorated the gait ataxia and the inflammatory response both centrally and peripherally. Our findings suggest that PHA-767491 has a broad spectrum of activity in the treatment of different PAD and that this activity could be based on the anti-inflammation mechanism.
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Antiinflamatorios/farmacología , Neuronas/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Piperidonas/farmacología , Agregación Patológica de Proteínas/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/farmacología , Pirroles/farmacología , Péptidos beta-Amiloides/toxicidad , Animales , Antiinflamatorios/uso terapéutico , Proteínas de Ciclo Celular/antagonistas & inhibidores , Proteínas de Ciclo Celular/metabolismo , Células Cultivadas , Cerebelo/efectos de los fármacos , Cerebelo/metabolismo , Quinasa 9 Dependiente de la Ciclina/antagonistas & inhibidores , Quinasa 9 Dependiente de la Ciclina/metabolismo , Proteínas de Unión al ADN/metabolismo , Hipocampo/citología , Humanos , Ratones , Ratones Endogámicos C57BL , Neuronas/metabolismo , Fármacos Neuroprotectores/uso terapéutico , Piperidonas/uso terapéutico , Agregación Patológica de Proteínas/metabolismo , Inhibidores de Proteínas Quinasas/uso terapéutico , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Proteínas Serina-Treonina Quinasas/metabolismo , Pirroles/uso terapéuticoRESUMEN
The pathogenesis of Alzheimer's disease (AD) is involved in the aggregation of misfolded amyloid ß (Aß), which upregulates the activity of acetylcholinesterase (AChE), increases the production of reactive oxygen species (ROS), enhances neuroinflammation, and eventually leads to neuronal death. Therefore, compounds targeting these mechanisms may be candidates for multitarget drugs in AD treatment. We found that two quinoline derivatives, VB-030 and VB-037, markedly reduced Aß aggregation and ROS levels in the thioflavin T biochemical assay and Tet-On Aß-green fluorescent protein (GFP) 293 AD cell model. These compounds further improved neurite outgrowth, reduced AChE activity and upregulated the molecular chaperone heat shock protein family B [small] member 1 (HSP27), whereas knockdown of HSP27 counteracted the compounds' neuroprotective effects on the Tet-On Aß-GFP SH-SY5Y AD neuronal model. Furthermore, VB-037 attenuated lipopolysaccharide (LPS)/interferon (IFN)-γ-induced activation of BV-2 microglial cells. In addition, VB-037 demonstrated its potential to diminish LPS/IFN-γ-induced upregulation of caspase 1 activity, expression of interleukin (IL)-1ß, and active phosphorylation of mitogen-activated protein kinase 14 (P38), mitogen-activated protein kinase 8 (JNK), and Jun proto-oncogene, AP-1 transcription factor subunit (JUN) signalings, as well as improve cell viability in the Tet-On Aß-GFP SH-SY5Y AD neuronal model. Our findings strongly indicate the potential of VB-037 for modifying AD progression by targeting multiple mechanisms, thereby offering a new drug development avenue for AD treatment.
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Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/metabolismo , Proteínas de Choque Térmico HSP27/metabolismo , Mediadores de Inflamación/metabolismo , Sistema de Señalización de MAP Quinasas/fisiología , Proyección Neuronal/fisiología , Quinolinas/farmacología , Quinolinas/uso terapéutico , Enfermedad de Alzheimer/tratamiento farmacológico , Péptidos beta-Amiloides/antagonistas & inhibidores , Animales , Línea Celular , Curcumina/farmacología , Humanos , Mediadores de Inflamación/antagonistas & inhibidores , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Ratones , Proyección Neuronal/efectos de los fármacos , Agregado de Proteínas/efectos de los fármacos , Agregado de Proteínas/fisiología , Proto-Oncogenes Mas , Quinolinas/química , Proteínas Quinasas p38 Activadas por Mitógenos/antagonistas & inhibidores , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismoRESUMEN
RATIONALE: Hyperglycemia accelerates the progression of Alzheimer's disease (AD), and GSK3ß plays a potential link between AD and hyperglycemia. Therefore, a direct or indirect GSK3ß inhibition may have potential to delay the progression of AD. Our previous biochemical assay identified AM404 as a GSK3ß inhibitor at high dose (IC50 = 5.353 µM); however, other study suggests that AM404 impaired synaptic plasticity of hippocampus at high dose (10 mg/kg; i.p.). Therefore, the dose and duration of treatment are crucial for the effects of AM404. OBJECTIVE: The effects and molecular mechanisms of AM404 at low dose were evaluated from in vitro to in vivo models. METHODS: AM404 (0.1-0.5 µM) was tested on tau hyperphosphorylated mouse hippocampal primary cultures treated with Wortmannin (WT) and GF109203X (GFX). Hyperglycemic triple transgenic AD (3×Tg-AD) mice at 6 months old were intraperitoneally injected with AM404 (0.25 mg/kg) for 4 weeks. The spatial learning and memory of mice were measured using the Morris water maze. Mouse brain and serum samples were collected for pathological analyses. RESULTS: AM404 (0.5 µM) exhibited significantly augmented neuroprotection toward tau hyperphosphorylation in primary cultures. The chronic systemic administration of AM404 (0.25 mg/kg) attenuated cognitive deficits in hyperglycemic 3×Tg-AD mice. Moreover, chronic low dose of AM404 significantly attenuated Aß production, tau protein phosphorylation, and inflammation associated with an increase of pS473Akt and pS9-GSK3ß. Therefore, AM404 at low dose, not only increased neuroprotection, but also ameliorated cognitive deficit, could be partly by regulating the Akt/GSK3ß signaling, which may contribute to downregulation of Aß, tau hyperphosphorylation, and inflammation in hyperglycemic 3×Tg-AD mice. CONCLUSIONS: These results highlight that chronic administration of AM404 at low dose may be through the Akt/GSK3ß pathway to ameliorate the impairment in hyperglycemic 3×Tg-AD mice.
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Ácidos Araquidónicos/administración & dosificación , Disfunción Cognitiva/tratamiento farmacológico , Hiperglucemia/tratamiento farmacológico , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/genética , Péptidos beta-Amiloides/metabolismo , Animales , Disfunción Cognitiva/genética , Disfunción Cognitiva/metabolismo , Relación Dosis-Respuesta a Droga , Esquema de Medicación , Femenino , Glucógeno Sintasa Quinasa 3 beta , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Humanos , Hiperglucemia/genética , Hiperglucemia/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Obesos , Ratones Transgénicos , Embarazo , Proteínas tau/genética , Proteínas tau/metabolismoRESUMEN
Utilizing the N-methyl-d-aspartate (NMDA) receptor antagonist as a strategy, memantine is the only agent available for clinically treating mild to severe Alzheimer's disease (AD). Our aim was to develop novel similar herb-based drugs. Using a screening platform, ginkgolide A (GA), a pure compound extracted from Ginkgo biloba, was found to attenuate amyloid ß (Aß)-induced abnormal depolarization in mouse primary cortical neurons. Using receptor agonists, it was determined that GA inhibits both NMDA receptors and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors. Furthermore, the Aß-induced increase in c-Jun N-terminal kinase phosphorylation in neurons was prevented by GA. Body weight, glutamate oxaloacetate transaminase, glutamic-pyruvic transaminase, liver histology, and kidney histology were similar when the wild-type/AD animal model mice with and without GA treatment were compared. This pure compound improves the memory of wild-type mice. Our findings indicate that GA has great potential clinically for the treatment of AD because it might target NMDA receptors just like memantine.
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Enfermedad de Alzheimer/prevención & control , Péptidos beta-Amiloides/toxicidad , Corteza Cerebral/efectos de los fármacos , Ginkgo biloba/química , Ginkgólidos/administración & dosificación , Lactonas/administración & dosificación , Neuronas/efectos de los fármacos , Fármacos Neuroprotectores/administración & dosificación , Extractos Vegetales/administración & dosificación , Enfermedad de Alzheimer/etiología , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/metabolismo , Animales , Corteza Cerebral/citología , Corteza Cerebral/metabolismo , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Neuronas/citología , Receptores de N-Metil-D-Aspartato/genética , Receptores de N-Metil-D-Aspartato/metabolismoRESUMEN
BACKGROUND: Mutations in the GRN (granulin precursor) are a frequent cause of frontotemporal dementia (FTD) and other atypical parkinsonian disorders. However, the frequency of GRN mutations in Asian patients with atypical parkinsonian disorders is still uncertain. METHODS: We screened GRN mutations by sequencing cDNA from 98 patients with FTD or atypical parkinsonian disorders. The functional properties of the identified mutation were evaluated by overexpression in human embryonic kidney (HEK)-293â¯cells. RESULTS: We identified a new missense (GRN p.T487I) mutation in a female patient with undefined atypical parkinsonism. The overexpression experiment further demonstrated that p.T487I mutation reduced the progranulin protein level and stability in HEK-293â¯cells. CONCLUSION: GRN p.T487I mutation, which decreases the stability of progranulin protein, could be a new causative mutation in patients with atypical parkinsonian disorders.
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Demencia Frontotemporal/genética , Trastornos Parkinsonianos/genética , Progranulinas/genética , Anciano , Femenino , Células HEK293 , Humanos , Masculino , Persona de Mediana Edad , Mutación Missense , TaiwánRESUMEN
Trehalose synthase (TS) catalyzes the reversible conversion of maltose to trehalose and belongs to glycoside hydrolase family 13 (GH13). Previous mechanistic analysis suggested a rate-limiting protein conformational change, which is probably the opening and closing of the active site. Consistently, crystal structures of Deinococcus radiodurans TS (DrTS) in complex with the inhibitor Tris displayed an enclosed active site for catalysis of the intramoleular isomerization. In this study, the apo structure of the DrTS N253F mutant displays a new open conformation with an empty active site. Analysis of these structures suggests that substrate binding induces a domain rotation to close the active site. Such a substrate-induced domain rotation has also been observed in some other GH13 enzymes.
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Deinococcus/enzimología , Glucosiltransferasas/química , Glucosiltransferasas/genética , Mutación , Dominio Catalítico , Cristalografía por Rayos X , Modelos Moleculares , Conformación Proteica , Especificidad por SustratoRESUMEN
GSK3ß kinase is a noteworthy target for discovery of the drugs that will be used to treat several diseases. In the effort to identify a new inhibitor lead compound, we utilized thermodynamic integration (TI)-molecular dynamics (MD) simulation and kinase assay to investigate the bindings between GSK3ß kinase and five compounds that were analogous to a known inhibitor with an available crystal structure. TI-MD simulations of the first two compounds (analogs 1 and 2) were used for calibration. The computed binding affinities of analogs 1 and 2 agreed well with the experimental results. The rest three compounds (analogs 3-5) were newly obtained from a database search, and their affinity data were newly measured in our labs. TI-MD simulations predicted the binding modes and the computed ΔΔG values have a reasonably good correlation with the experimental affinity data. These newly identified inhibitors appear to be new leads according to our survey of GSK3ß inhibitors listed in recent review articles. The predicted binding modes of these compounds should aid in designing new derivatives of these compounds in the future.
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Glucógeno Sintasa Quinasa 3 beta/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/farmacología , Glucógeno Sintasa Quinasa 3 beta/metabolismo , Humanos , Simulación del Acoplamiento Molecular , Simulación de Dinámica Molecular , Unión Proteica , TermodinámicaRESUMEN
PH20 is known as sperm adhesion molecule 1 (SPAM1) and also has hyaluronidase function to preferentially hydrolyze the glycosidic linkage of hyaluronic acid (HA). A DNA fragment containing core domain of human PH20 gene was cloned into a constitutive expression plasmid (pGAPZαC) of Pichia pastoris to produce a fusion protein with α factor signal in the N-terminus and 6 × His as well as c-Myc tags in the C-terminus. The resulting plasmid pGAPZαC-PH20 was integrated into the genome of P. pastoris strain GS115. Functional recombinant human PH20 (rHuPH20) was successfully expressed and secreted by the recombinant P. pastoris transformant. Highest hyaluronidase activity of 2 mU/mL could be obtained at 3 day in an YPD culture. After purified by phenylboronic acid resin adsorption, rHuPH20 with a specific activity of 230 mU/mg was obtained. Via periodic acid-Schiff staining and zymogram analysis, the partially purified rHuPH20 was determined to be highly glycosylated to various extents with molecular mass in the range of 100-300 kDa. The enzyme showed a maximal activity at pH 5.0 but no appreciable activity at pH ≤3 and pH ≥8. The hyaluronidase activity could be stably maintained at 4°C but lost 40% after incubating at 30°C for 4 h. Both N-acetyl cysteine and glutathione showed a half maximal inhibitory concentration (IC50) of 8 mM against rHuPH20.
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Moléculas de Adhesión Celular/genética , Hialuronoglucosaminidasa/genética , Pichia/genética , Pichia/metabolismo , Proteínas Recombinantes/genética , Moléculas de Adhesión Celular/metabolismo , Clonación Molecular , Regulación Fúngica de la Expresión Génica , Glicosilación , Humanos , Ácido Hialurónico/metabolismo , Hialuronoglucosaminidasa/metabolismo , Ingeniería Metabólica , Peso Molecular , Organismos Modificados Genéticamente , Proteínas Recombinantes/metabolismo , TransfecciónRESUMEN
Glycogen synthase kinase 3ß (GSK-3ß) is widely known as a critical target protein for treating Alzheimer's disease (AD). We utilized virtual screening to search databases for compounds with the potential to be used in drugs targeting GSK-3ß kinase, and kinase as well as cell assays to investigate top-scored, selected compounds. Virtual screening of >1.1 million compounds in the ZINC and in-house databases was conducted using an optimized computational protocol in the docking program GOLD. Of the top-ranked compounds, 16 underwent a luminescent kinase assay and a cell assay using HEK293 cells expressing DsRed-tagged ΔK280 in the repeat domain of tau (tauRD). The compounds VB-003 (a potent GSK-3ß inhibitor) and VB-008 (AM404, an anandamide transport inhibitor), with determined IC50 values of 0.25 and 5.4µM, respectively, were identified as reducing tau aggregation. Both compounds increased expression of phospho-GSK-3ß (Ser9) and reduced endogenous tau phosphorylation at the sites of Ser202, Thr231, and Ser396. In the ∆K280 tauRD-DsRed SH-SY5Y cells, VB-008, but not VB-003, enhanced HSPB1 and GRP78 expression, increased ∆K280 tauRD-DsRed solubility, and promoted neurite outgrowth. Thus VB-008 performed best to the end of the present study. The identified compound VB-008 may guide the identification and synthesis of potential inhibitors analogous to this compound.
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Enfermedad de Alzheimer/tratamiento farmacológico , Inhibidores Enzimáticos/farmacología , Glucógeno Sintasa Quinasa 3 beta/antagonistas & inhibidores , Enfermedad de Alzheimer/metabolismo , Línea Celular , Chaperón BiP del Retículo Endoplásmico , Células HEK293 , Humanos , Neuritas/efectos de los fármacos , Fosforilación/efectos de los fármacos , Proteínas tau/metabolismoRESUMEN
Trehalose, a chemical chaperone and mTOR-independent autophagy enhancer, has shown promise in models of Huntington's disease, Parkinson's disease and tauopathies. In this study, two trehalase analogs, lactulose and melibiose, were examined for their potentials in spinocerebellar ataxia treatment. Using a SCA3 ATXN3/Q75-GFP cell model, we found that the ATXN3/Q75 aggregation was significantly prohibited by lactulose and melibiose because of their abilities to up-regulate autophagy. Meanwhile, lactulose and melibiose reduced reactive oxygen species production in ATXN3/Q75 cells. Both of them further inhibited the ATXN3/Q75 aggregation in neuronally differentiated SH-SY5Y cells. These findings suggest the therapeutic applications of novel trehalose analogs in polyglutamine aggregation-associated neurodegenerative diseases.
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Ataxina-3/metabolismo , Autofagia/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos , Lactulosa/farmacología , Melibiosa/farmacología , Péptidos/metabolismo , Proteínas Represoras/metabolismo , Análisis de Varianza , Ataxina-3/genética , Autofagia/genética , Línea Celular Tumoral , Regulación de la Expresión Génica/genética , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Humanos , Lactulosa/química , Melibiosa/química , Neuroblastoma/patología , Péptidos/genética , Agregación Patológica de Proteínas/tratamiento farmacológico , Especies Reactivas de Oxígeno/metabolismo , Proteínas Represoras/genética , Transfección , Trehalosa/farmacologíaRESUMEN
The versatile Candida rugosa lipase (CRL) has been widely used in biotechnological applications. However, there have not been feasibility reports on the transesterification of non-edible oils to produce biodiesel using the commercial CRL preparations, mixtures of isozymes. In the present study, four liquid recombinant CRL isozymes (CRL1-CRL4) were investigated to convert various non-edible oils into biodiesel. The results showed that recombinant CRL2 and CRL4 exhibited superior catalytic efficiencies for producing fatty acid methyl ester (FAME) from Jatropha curcas seed oil. A maximum 95.3% FAME yield was achieved using CRL2 under the optimal conditions (50 wt% water, an initial 1 equivalent of methanol feeding, and an additional 0.5 equivalents of methanol feeding at 24h for a total reaction time of 48 h at 37 °C). We concluded that specific recombinant CRL isozymes could be excellent biocatalysts for the biodiesel production from low-cost crude Jatropha oil.
Asunto(s)
Biocombustibles/microbiología , Candida/enzimología , Isoenzimas/química , Jatropha/química , Lipasa/química , Aceites de Plantas/química , Semillas/química , Biotecnología/métodos , Catálisis , Esterificación , Ácidos Grasos/química , Metanol/químicaRESUMEN
The unique property of trehalose encourages its pharmaceutical application in aggregation-mediated neurodegenerative disorders, including Alzheimer's, Parkinson's, and many polyglutamine (polyQ)-mediated diseases. However, trehalose is digested into glucose by trehalase and which reduced its efficacy in the disease target tissues. Therefore, searching trehalase-indigestible analogs of trehalose is a potential strategy to enhance therapeutic effect. In this study, two trehalase-indigestible trehalose analogs, lactulose and melibiose, were selected through compound topology and functional group analyses. Hydrogen-bonding network analyses suggest that the elimination of the hydrogen bond between the linker ether and aspartate 321 (D321) of human trehalase is the key for lactulose and melibiose to avoid the hydrolyzation. Using polyQ-mediated spinocerebellar ataxia type 17 (SCA17) cell and slice cultures, we found the aggregation was significantly prohibited by trehalose, lactulose, and melibiose, which may through up-regulating of autophagy. These findings suggest the therapeutic applications of trehalase-indigestible trehalose analogs in aggregation-associated neurodegenerative diseases.