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1.
Molecules ; 26(20)2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34684818

RESUMO

The use of monoamine oxidases (MAOs) in amine oxidation is a great example of how biocatalysis can be applied in the agricultural or pharmaceutical industry and manufacturing of fine chemicals to make a shift from traditional chemical synthesis towards more sustainable green chemistry. This article reports the screening of fourteen Antarctic fungi strains for MAO activity and the discovery of a novel psychrozyme MAOP3 isolated from the Pseudogymnoascus sp. P3. The activity of the native enzyme was 1350 ± 10.5 U/L towards a primary (n-butylamine) amine, and 1470 ± 10.6 U/L towards a secondary (6,6-dimethyl-3-azabicyclohexane) amine. MAO P3 has the potential for applications in biotransformations due to its wide substrate specificity (aliphatic and cyclic amines, pyrrolidine derivatives). The psychrozyme operates at an optimal temperature of 30 °C, retains 75% of activity at 20 °C, and is rather thermolabile, which is beneficial for a reduction in the overall costs of a bioprocess and offers a convenient way of heat inactivation. The reported biocatalyst is the first psychrophilic MAO; its unique biochemical properties, substrate specificity, and effectiveness predispose MAO P3 for use in environmentally friendly, low-emission biotransformations.


Assuntos
Aminas/metabolismo , Ascomicetos/enzimologia , Proteínas Fúngicas/metabolismo , Monoaminoxidase/metabolismo , Aminas/química , Ascomicetos/classificação , Ascomicetos/genética , Biocatálise , Temperatura Baixa , Proteínas Fúngicas/química , Proteínas Fúngicas/isolamento & purificação , Química Verde/métodos , Cinética , Modelos Moleculares , Monoaminoxidase/química , Monoaminoxidase/isolamento & purificação , Inibidores da Monoaminoxidase/farmacologia , Oxirredução , Conformação Proteica , Especificidade por Substrato
2.
Biomed Res Int ; 2021: 2593748, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34447850

RESUMO

Artificial intelligence technologies such as machine learning have been applied to protein engineering, with unique advantages in protein structure, function prediction, catalytic activity, and other issues in recent years. Screening better mutants is still a bottleneck in protein engineering. In this paper, a new sequence-activity relationship method was analyzed for its application in improving the thermal stability of Aspergillus terreus (R)-ω-selective amine transaminase. The experimental data from 6 single-point mutated enzymes were used as a learning dataset to build models and predict the thermostability of 26 mutants. Based on digital signal processing (DSP), this method digitized the amino acid sequence of proteins by fast Fourier transform (FFT) and then established the best model applying partial least squares regression (PLSR) to screen out all possible mutants, especially those with high performance. In protein engineering, the innovative sequence activity relationship (ISAR) method can make a reasonable prediction using limited experimental data and significantly reduce the experimental cost. The half-life (T 1/2) of (R)-ω-transaminase was fitted with the amino acid sequence by the ISAR algorithm, resulting in an R 2 of 0.8929 and a cvRMSE of 4.89. At the same time, the mutants with higher T 1/2 than the existing ones were predicted, laying the groundwork for better (R)-ω-transaminase in the later stage. The ISAR algorithm is expected to provide a new technique for protein evolution and screening.


Assuntos
Aminas/química , Aspergillus/enzimologia , Aprendizado de Máquina , Transaminases/química , Aminas/metabolismo , Aspergillus/química , Temperatura Alta , Modelos Moleculares , Engenharia de Proteínas/métodos , Estabilidade Proteica , Elementos Estruturais de Proteínas , Especificidade por Substrato , Transaminases/metabolismo
3.
ACS Chem Biol ; 16(9): 1654-1662, 2021 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-34423964

RESUMO

Marine tunicates produce defensive amino-acid-derived metabolites, including 2-(3,5-diiodo-4-methoxyphenyl)ethan-1-amine (DIMTA), but their mechanisms of action are rarely known. Using an assay-guided approach, we found that out of the many different sensory cells in the mouse dorsal root ganglion (DRG), DIMTA selectively affected low-threshold cold thermosensors. Whole-cell electrophysiology experiments using DRG cells, channels expressed in Xenopus oocytes, and human cell lines revealed that DIMTA blocks several potassium channels, reducing the magnitude of the afterhyperpolarization and increasing the baseline intracellular calcium concentration [Ca2+]i of low-threshold cold thermosensors. When injected into mice, DIMTA increased the threshold of cold sensation by >3 °C. DIMTA may thus serve as a lead in the further design of compounds that inhibit problems in the cold-sensory system, such as cold allodynia and other neuropathic pain conditions.


Assuntos
Aminas/metabolismo , Canais de Cálcio/metabolismo , Células Receptoras Sensoriais/metabolismo , Aminas/administração & dosagem , Animais , Cálcio/metabolismo , Gânglios Espinais/metabolismo , Masculino , Camundongos , Técnicas de Patch-Clamp , Transdução de Sinais , Sensação Térmica/fisiologia , Urocordados , Vertebrados
4.
J Med Chem ; 64(12): 8545-8563, 2021 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-34110134

RESUMO

Aromatic and heteroaromatic amines (ArNH2) are activated by cytochrome P450 monooxygenases, primarily CYP1A2, into reactive N-arylhydroxylamines that can lead to covalent adducts with DNA nucleobases. Hereby, we give hands-on mechanism-based guidelines to design mutagenicity-free ArNH2. The mechanism of N-hydroxylation of ArNH2 by CYP1A2 is investigated by density functional theory (DFT) calculations. Two putative pathways are considered, the radicaloid route that goes via the classical ferryl-oxo oxidant and an alternative anionic pathway through Fenton-like oxidation by ferriheme-bound H2O2. Results suggest that bioactivation of ArNH2 follows the anionic pathway. We demonstrate that H-bonding and/or geometric fit of ArNH2 to CYP1A2 as well as feasibility of both proton abstraction by the ferriheme-peroxo base and heterolytic cleavage of arylhydroxylamines render molecules mutagenic. Mutagenicity of ArNH2 can be removed by structural alterations that disrupt geometric and/or electrostatic fit to CYP1A2, decrease the acidity of the NH2 group, destabilize arylnitrenium ions, or disrupt their pre-covalent transition states with guanine.


Assuntos
Aminas/metabolismo , Citocromo P-450 CYP1A2/metabolismo , Compostos Heterocíclicos/metabolismo , Hidrocarbonetos Aromáticos/metabolismo , Mutagênicos/metabolismo , Aminas/química , Domínio Catalítico , Cristalografia por Raios X , Citocromo P-450 CYP1A2/química , Teoria da Densidade Funcional , Análise Discriminante , Compostos Heterocíclicos/química , Humanos , Hidrocarbonetos Aromáticos/química , Hidroxilação , Análise dos Mínimos Quadrados , Modelos Químicos , Estrutura Molecular , Mutagênicos/química , Ligação Proteica
5.
Appl Environ Microbiol ; 87(17): e0074821, 2021 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-34160271

RESUMO

Several fungi, including the plant root symbiont and insect pathogen Metarhizium brunneum, produce lysergic acid amides via a branch of the ergot alkaloid pathway. Lysergic acid amides include important pharmaceuticals and pharmaceutical lead compounds and have potential ecological significance, making knowledge of their biosynthesis relevant. Many steps in the biosynthesis of lysergic acid amides have been determined, but terminal steps in the synthesis of lysergic acid α-hydroxyethylamide (LAH)-by far the most abundant lysergic acid amide in M. brunneum-are unknown. Ergot alkaloid synthesis (eas) genes are clustered in the genomes of fungi that produce these compounds, and the eas clusters of LAH producers contain two uncharacterized genes (easO and easP) not found in fungi that do not produce LAH. Knockout of easO via a CRISPR-Cas9 approach eliminated LAH and resulted in accumulation of the alternate lysergic acid amides lysergyl-alanine and ergonovine. Despite the elimination of LAH, the total concentration of lysergic acid derivatives was not affected significantly by the mutation. Complementation with a wild-type allele of easO restored the ability to synthesize LAH. Substrate feeding studies indicated that neither lysergyl-alanine nor ergonovine were substrates for the product of easO (EasO). EasO had structural similarity to Baeyer-Villiger monooxygenases (BVMOs), and labeling studies with deuterated alanine supported a role for a BVMO in LAH biosynthesis. The easO knockout had reduced virulence to larvae of the insect Galleria mellonella, indicating that LAH contributes to virulence of M. brunneum on insects and that LAH has biological activities different from ergonovine and lysergyl-alanine. IMPORTANCE Fungi in the genus Metarhizium are important plant root symbionts and insect pathogens. They are formulated commercially to protect plants from insect pests. Several Metarhizium species, including M. brunneum, were recently shown to produce ergot alkaloids, a class of specialized metabolites studied extensively in other fungi because of their importance in agriculture and medicine. A biological role for ergot alkaloids in Metarhizium species had not been demonstrated previously. Moreover, the types of ergot alkaloids produced by Metarhizium species are lysergic acid amides, which have served directly or indirectly as important pharmaceutical compounds. The terminal steps in the synthesis of the most abundant lysergic acid amide in Metarhizium species and several other fungi (LAH) have not been determined. The results of this study demonstrate the role of a previously unstudied gene in LAH synthesis and indicate that LAH contributes to virulence of M. brunneum on insects.


Assuntos
Aminas/metabolismo , Proteínas Fúngicas/metabolismo , Ácido Lisérgico/metabolismo , Metarhizium/enzimologia , Oxigenases de Função Mista/metabolismo , Animais , Vias Biossintéticas , Proteínas Fúngicas/genética , Larva/microbiologia , Metarhizium/genética , Metarhizium/metabolismo , Metarhizium/patogenicidade , Oxigenases de Função Mista/genética , Mariposas/microbiologia , Virulência
6.
Eur J Med Chem ; 223: 113648, 2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34175535

RESUMO

The HGF/Met signaling pathway is over-expressed in many types of cancers and closely related to oncogenesis and metastasis. Thus, we developed novel N-phenylpyrimidin-2-amine derivatives to test their inhibitory activities towards c-Met kinase, and most of the compounds (15a-i, 15o-r, 20 and 34a-c) could inhibit the target with IC50 values from 550.8 nM to 15.0 nM. Subsequently, compound 15b, 15d, 15f, 15i, 15o, 15r, 20, 34a and 34b also showed high antiproliferative activities in c-Met sensitive tumor cell lines (PC-3, Panc-1, HepG2, HCT116 and Caki-1) with IC50 values from 0.53 to 1.37 µM. The lead compound 34a displayed outstanding c-Met inhibitory activity (IC50: 15.0 nM) and antiproliferative activities. Furthermore, 34a also performed favorable pharmacokinetic properties in mice (F%: 59.3) and an acceptable safety profile in preclinical studies. Further docking studies showed a common interaction of 34a with c-Met at the ATP-binding site, which indicated that 34a could be a potential candidate for c-Met inhibitors.


Assuntos
Aminas/química , Desenho de Fármacos , Inibidores de Proteínas Quinases/química , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Aminas/metabolismo , Aminas/farmacologia , Animais , Sítios de Ligação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Meia-Vida , Humanos , Masculino , Camundongos , Simulação de Acoplamento Molecular , Inibidores de Proteínas Quinases/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-met/metabolismo , Ratos , Ratos Sprague-Dawley , Relação Estrutura-Atividade
7.
Cells ; 10(5)2021 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-34064617

RESUMO

Persistent pain is a prevalent symptom of Parkinson's disease (PD), which is related to the loss of monoamines and neuroinflammation. Motor cortex stimulation (MCS) inhibits persistent pain by activating the descending analgesic pathways; however, its effectiveness in the control of PD-induced pain remains unclear. Here, we evaluated the analgesic efficacy of MCS together with serotonergic and spinal glial modulation in an experimental PD (ePD) rat model. Wistar rats with unilateral striatal 6-OHDA and MCS were assessed for behavioral immobility and nociceptive responses. The immunoreactivity of dopamine in the substantia nigra and serotonin in the nucleus raphe magnus (NRM) and the neuronal, astrocytic, and microglial activation in the dorsal horn of the spinal cord were evaluated. MCS, without interfering with dopamine loss, reversed ePD-induced immobility and hypernociception. This response was accompanied by an exacerbated increase in serotonin in the NRM and a decrease in neuronal and astrocytic hyperactivation in the spinal cord, without inhibiting ePD-induced microglial hypertrophy and hyperplasia. Taken together, MCS induces analgesia in the ePD model, while restores the descending serotonergic pathway with consequent inhibition of spinal neurons and astrocytes, showing the role of MCS in PD-induced pain control.


Assuntos
Astrócitos/metabolismo , Córtex Motor/fisiologia , Nociceptividade , Doença de Parkinson/metabolismo , Núcleos da Rafe/metabolismo , Serotonina/metabolismo , Aminas/metabolismo , Analgesia , Animais , Comportamento Animal , Modelos Animais de Doenças , Dopamina/metabolismo , Eletrodos , Inflamação , Masculino , Córtex Motor/metabolismo , Neuroglia/metabolismo , Neurônios/metabolismo , Dor/complicações , Manejo da Dor , Ratos , Ratos Wistar , Medula Espinal/metabolismo
8.
Nat Microbiol ; 6(6): 792-805, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33846627

RESUMO

Human physiology is regulated by endogenous signalling compounds, including fatty acid amides (FAAs), chemical mimics of which are made by bacteria. The molecules produced by human-associated microbes are difficult to identify because they may only be made in a local niche or they require a substrate sourced from the host, diet or other microbes. We identified a set of uncharacterized gene clusters in metagenomics data from the human gut microbiome. These clusters were discovered to make FAAs by fusing exogenous fatty acids with amines. Using an in vitro assay, we tested their ability to incorporate 25 fatty acids and 53 amines known to be present in the human gut, from which the production of six FAAs was deduced (oleoyl dopamine, oleoyl tyramine, lauroyl tryptamine, oleoyl aminovaleric acid, α-linolenoyl phenylethylamine and caproyl tryptamine). These molecules were screened against panels of human G-protein-coupled receptors to deduce their putative human targets. Lauroyl tryptamine is found to be an antagonist to the immunomodulatory receptor EBI2 against its native oxysterol ligand (0.98 µM half-maximal inhibitory concentration), is produced in culture by Eubacterium rectale and is present in human faecal samples. FAAs produced by Clostridia may serve as a mechanism to modulate their host by mimicking human signalling molecules.


Assuntos
Aminas/metabolismo , Ácidos Graxos/metabolismo , Firmicutes/metabolismo , Microbioma Gastrointestinal , Neurotransmissores/metabolismo , Aminas/química , Dieta , Ácidos Graxos/química , Firmicutes/classificação , Firmicutes/genética , Trato Gastrointestinal/metabolismo , Trato Gastrointestinal/microbiologia , Humanos , Neurotransmissores/química , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Transdução de Sinais
9.
Life Sci ; 277: 119532, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-33891943

RESUMO

PURPOSE: The rise in consumption of dietary supplements containing the trace amines p-tyramine, p-synephrine and p-octopamine has been associated with cardiovascular side effects. Since renal blood flow plays an important role in blood pressure regulation, this study investigated the mechanisms of action of these trace amines on isolated porcine renal arteries. MAIN METHODS: Contractile responses to amines were investigated in noradrenaline-depleted rings of porcine main renal arteries in the absence and presence of the α1-adrenoceptor antagonist, prazosin (1 µM), ß-adrenoceptor antagonist, propranolol (1 µM), or the trace amine-associated receptor (TAAR-1) antagonist, EPPTB (RO-5212773; 100 nM or 100 µM). KEY FINDINGS: All three amines induced constrictor responses of similar magnitude and potency. However, their mechanisms of action on the renal artery appeared to differ. Depleting endogenous noradrenaline stores significantly reduced maximum responses to tyramine and synephrine, but less for octopamine. When direct responses were examined after depleting tissues of noradrenaline, responses to synephrine and octopamine, but not tyramine, were reduced in the presence of prazosin(1 µM) and potentiated in the presence of propranolol (1 µM) or L-NNA (100 µM). Generally, vasoconstrictor responses remaining after noradrenaline-depletion and α-adrenoceptor blockade were not affected by the TAAR-1 antagonist EPPTB (0.1-100 µM), although responses to low concentration of synephrine and octopamine were enhanced by this antagonist. SIGNIFICANCE: Tyramine appears to mediate constriction of the renal artery mainly via an indirect sympathomimetic mechanism, whereas synephrine and octopamine exert additional direct effects on α1-adrenoceptors and possibly contractile TAAR (not TAAR-1). The two amines also activate simultaneous inhibitory responses via ß-adrenoceptors, TAAR-1 and nitric oxide release.


Assuntos
Aminas/metabolismo , Aminas/farmacologia , Artéria Renal/metabolismo , Aminas/química , Animais , Feminino , Norepinefrina/farmacologia , Octopamina/farmacologia , Fenetilaminas/farmacologia , Propranolol/farmacologia , Artéria Renal/efeitos dos fármacos , Suínos , Simpatomiméticos/farmacologia , Sinefrina/farmacologia , Tiramina/farmacologia , Vasoconstrição/efeitos dos fármacos , Vasoconstritores/farmacologia
10.
Int J Mol Sci ; 22(7)2021 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-33805974

RESUMO

The semicarbazide-sensitive amine oxidase (SSAO), also known as vascular adhesion protein-1 (VAP-1) or primary amine oxidase (PrAO), is a deaminating enzyme highly expressed in vessels that generates harmful products as a result of its enzymatic activity. As a multifunctional enzyme, it is also involved in inflammation through its ability to bind and promote the transmigration of circulating leukocytes into inflamed tissues. Inflammation is present in different systemic and cerebral diseases, including stroke and Alzheimer's disease (AD). These pathologies show important affectations on cerebral vessels, together with increased SSAO levels. This review summarizes the main roles of SSAO/VAP-1 in human physiology and pathophysiology and discusses the mechanisms by which it can affect the onset and progression of both stroke and AD. As there is an evident interrelationship between stroke and AD, basically through the vascular system dysfunction, the possibility that SSAO/VAP-1 could be involved in the transition between these two pathologies is suggested. Hence, its inhibition is proposed to be an interesting therapeutical approach to the brain damage induced in these both cerebral pathologies.


Assuntos
Doença de Alzheimer/terapia , Amina Oxidase (contendo Cobre)/metabolismo , Moléculas de Adesão Celular/metabolismo , Transtornos Cerebrovasculares/terapia , Acidente Vascular Cerebral/terapia , Doença de Alzheimer/metabolismo , Aminas/metabolismo , Animais , Adesão Celular , Angiopatia Amiloide Cerebral/metabolismo , Transtornos Cerebrovasculares/metabolismo , Progressão da Doença , Células Endoteliais/metabolismo , Glucose/metabolismo , Humanos , Inflamação/terapia , Leucócitos/citologia , Camundongos , Ratos , Acidente Vascular Cerebral/metabolismo
11.
Angew Chem Int Ed Engl ; 60(34): 18660-18665, 2021 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-33856106

RESUMO

A key aim of biocatalysis is to mimic the ability of eukaryotic cells to carry out multistep cascades in a controlled and selective way. As biocatalytic cascades get more complex, reactions become unattainable under typical batch conditions. Here a number of continuous flow systems were used to overcome batch incompatibility, thus allowing for successful biocatalytic cascades. As proof-of-principle, reactive carbonyl intermediates were generated in situ using alcohol oxidases, then passed directly to a series of packed-bed modules containing different aminating biocatalysts which accordingly produced a range of structurally distinct amines. The method was expanded to employ a batch incompatible sequential amination cascade via an oxidase/transaminase/imine reductase sequence, introducing different amine reagents at each step without cross-reactivity. The combined approaches allowed for the biocatalytic synthesis of the natural product 4O-methylnorbelladine.


Assuntos
Oxirredutases do Álcool/metabolismo , Aminas/metabolismo , Produtos Biológicos/metabolismo , Aminas/química , Biocatálise , Produtos Biológicos/química , Estrutura Molecular
12.
Biomolecules ; 11(3)2021 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-33673489

RESUMO

The mammalian target of rapamycin (mTOR), a serine/ threonine kinase, is implicated in synaptic plasticity by controlling protein synthesis. Research suggests that ethanol exposure during pregnancy alters the mTOR signaling pathway in the fetal hippocampus. Thus, we investigated the influence of pre-treatment with rapamycin, an mTORC1 inhibitor, on the development of recognition memory deficits in adult rats that were neonatally exposed to ethanol. In the study, male and female rat pups received ethanol (5 g/kg/day) by intragastric intubation at postanatal day (PND 4-9), an equivalent to the third trimester of human pregnancy. Rapamycin (3 and 10 mg/kg) was given intraperitoneally before every ethanol administration. Short- and long-term recognition memory was assessed in the novel object recognition (NOR) task in adult (PND 59/60) rats. Locomotor activity and anxiety-like behavior were also evaluated to exclude the influence of such behavior on the outcome of the memory task. Moreover, the effects of rapamycin pre-treatment during neonatal ethanol exposure on the content of amino-acids and amines essential for the proper development of cognitive function in the dentate gyrus (DG) of the hippocampus was evaluated using proton magnetic resonance spectroscopy (1H MRS) in male adult (PND 60) rats. Our results show the deleterious effect of ethanol given to neonatal rats on long-term recognition memory in adults. The effect was more pronounced in male rather than female rats. Rapamycin reversed this ethanol-induced memory impairment and normalized the levels of amino acids and amines in the DG. This suggests the involvement of mTORC1 in the deleterious effect of ethanol on the developing brain.


Assuntos
Envelhecimento/fisiologia , Aminas/metabolismo , Aminoácidos/metabolismo , Giro Denteado/metabolismo , Etanol/toxicidade , Memória/efeitos dos fármacos , Reconhecimento Psicológico/efeitos dos fármacos , Sirolimo/farmacologia , Animais , Animais Recém-Nascidos , Ansiedade/patologia , Comportamento Animal/efeitos dos fármacos , Giro Denteado/efeitos dos fármacos , Teste de Labirinto em Cruz Elevado , Etanol/administração & dosagem , Feminino , Masculino , Atividade Motora/efeitos dos fármacos , Espectroscopia de Prótons por Ressonância Magnética , Ratos Wistar
13.
Eur J Pharm Biopharm ; 163: 109-119, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33775852

RESUMO

We aim to prepare a size-shifting nanocarrier for site-targeting mucosal drug delivery that can penetrate through mucus gel layer and remain close to the absorption membrane. As nanocarriers can be engineered to penetrate mucus but they can also back diffuse into outer mucus regions, a size shifting to micron range once they have reached the absorption membrane would prevent back-diffusion effect and extend drug release over a long period of time. For this purpose, we loaded solid lipid nanoparticles (SLN) with a phosphate ester surfactant and octadecylamine. Alkaline phosphatase (AP), a membrane bound enzyme was for the first time utilized as an in situ partner for triggering the size conversion at epithelial cell surface. Having the size of ~120 nm, SLN with hydrophilic and phosphate-decorated shells were shown to penetrate through mucus gel and form aggregates above cell layer surface. Aggregates of 5-8 µm were formed due to interparticle interactions induced by enzymatic phosphate removal after ~30 min in contact with isolated AP. The developed SLN system could be a potential tool for mucosal drug delivery to AP-expressing tissues like colon, lung, cervix, vagina and some mucus-secreting tumors.


Assuntos
Fosfatase Alcalina/metabolismo , Portadores de Fármacos/metabolismo , Muco/enzimologia , Nanopartículas/metabolismo , Administração através da Mucosa , Aminas/química , Aminas/metabolismo , Animais , Células CACO-2 , Curcumina/administração & dosagem , Curcumina/farmacocinética , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Humanos , Interações Hidrofóbicas e Hidrofílicas , Lipídeos/química , Nanopartículas/química , Tamanho da Partícula , Tensoativos/química , Tensoativos/metabolismo , Sus scrofa
14.
Eur J Med Chem ; 216: 113310, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33667847

RESUMO

A novel series of dimethylamino chalcone-O-alkylamines derivatives was designed and synthesized as multifunctional agents for the treatment of AD. All the target compounds exhibited significant abilities to inhibit and disaggregate Aß aggregation, and acted as potential selective AChE inhibitors, biometal chelators and selective MAO-B inhibitors. Among these compounds, compound TM-6 showed the greatest inhibitory activity against self-induced Aß aggregation (IC50 = 0.88 µM) and well disaggregation ability toward self-induced Aß aggregation (95.1%, 25 µM), the TEM images, molecular docking study and molecular dynamics simulations provided reasonable explanation for its high efficiency, and it was also found to be a remarkable antioxidant (ORAC-FL values of 2.1eq.), the best AChE inhibitor (IC50 = 0.13 µM) and MAO-B inhibitor (IC50 = 1.0 µM), as well as a good neuroprotectant. UV-visual spectrometry and ThT fluorescence assay revealed that compound TM-6 was not only a good biometal chelator by inhibiting Cu2+-induced Aß aggregation (95.3%, 25 µM) but also could disassemble the well-structured Aß fibrils (88.1%, 25 µM). Further, TM-6 could cross the blood-brain barrier (BBB) in vitro. More importantly, compound TM-6 did not show any acute toxicity in mice at doses of up to 1000 mg/kg and improved scopolamine-induced memory impairment. Taken together, these data indicated that TM-6, an excellent balanced multifunctional inhibitor, was a potential lead compound for the treatment of AD.


Assuntos
Aminas/química , Desenho de Fármacos , Fármacos Neuroprotetores/química , Acetilcolinesterase/química , Acetilcolinesterase/metabolismo , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/patologia , Aminas/metabolismo , Aminas/farmacologia , Aminas/uso terapêutico , Peptídeos beta-Amiloides/química , Peptídeos beta-Amiloides/metabolismo , Animais , Antioxidantes/química , Sítios de Ligação , Sobrevivência Celular/efeitos dos fármacos , Chalcona/química , Humanos , Cinética , Metais/química , Metais/metabolismo , Simulação de Acoplamento Molecular , Monoaminoxidase/química , Monoaminoxidase/metabolismo , Fármacos Neuroprotetores/metabolismo , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Células PC12 , Agregados Proteicos/efeitos dos fármacos , Ratos , Relação Estrutura-Atividade
15.
Molecules ; 26(5)2021 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-33652771

RESUMO

The aim of this research was to investigate the effect of the number of freeze-thaw cycles (0, 1, 3, 5, and 7) on porcine longissimus protein and lipid oxidation, as well as changes in heterocyclic aromatic amines (HAAs) and advanced glycation end products (AGEs) and their precursors. We analyzed the relationship among HAAs, AGEs, oxidation, and precursors and found the following results after seven freeze-thaw cycles. The HAAs, Norharman and Harman, were 20.33% and 16.67% higher, respectively. The AGEs, Nε-carboxyethyllysine (CEL) and Nε-carboxymethyllysine (CML), were 11.81% and 14.02% higher, respectively. Glucose, creatine, and creatinine were reduced by 33.92%, 5.93%, and 1.12%, respectively after seven freeze-thaw cycles. Norharman was significantly correlated with thiobarbituric acid reactive substances (TBARS; r2 = 0.910) and glucose (r2 = -0.914). Harman was significantly correlated to TBARS (r2 = 0.951), carbonyl (r2 = 0.990), and glucose (r2 = -0.920). CEL was correlated to TBARS (r2 = 0.992) and carbonyl (r2 = 0.933). These changes suggest that oxidation and the Maillard reaction during freeze-thaw cycles promote HAA and AGE production in raw pork.


Assuntos
Tecido Adiposo/metabolismo , Aminas/metabolismo , Compostos Heterocíclicos/metabolismo , Proteínas/metabolismo , Aminas/química , Animais , Galinhas , Culinária , Congelamento/efeitos adversos , Compostos Heterocíclicos/química , Humanos , Reação de Maillard , Carne/análise , Oxirredução , Carne de Porco/análise , Suínos , Substâncias Reativas com Ácido Tiobarbitúrico/química , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
16.
Acc Chem Res ; 54(7): 1711-1722, 2021 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-33576600

RESUMO

Organonitrogen chemicals are essential in many aspects of modern life. Over 80% of the top 200 prescribed pharmaceutical products contain at least one nitrogen atom in the molecule, while all top 10 agrochemicals contain nitrogen, just to name a few. At present, the prevailing industrial processes for manufacturing organonitrogen chemicals start from nonrenewable fossil resources, but eventually we have to make these chemicals in a more sustainable manner. Biomass represents the largest renewable carbon resource on earth, which is inexpensive and widely available. Integrating biomass into the organonitrogen chemical supply chain will mitigate the carbon footprint, diversify the product stream, and enhance the economic competitiveness of biorefinery. Short-cut synthesis routes can be created for oxygen-containing organonitrogen compounds by exploiting the inherent oxygen functionalities in the biomass resources. Moreover, for nitrogen-containing biomass components such as chitin, a unique opportunity to make organonitrogen chemicals bypassing the energy-intensive Haber-Bosch ammonia synthesis process arises. Estimated at 100 billion tons of annual production in the world, chitin captures more nitrogen than the Haber-Bosch process in the form of amide functional groups in its polymer side chain.In this Account, we intend to summarize our efforts to establish new reaction routes to synthesize valuable organonitrogen chemicals from renewable resources. Enabled by tailor-designed catalytic systems, diverse nitrogen-containing products including amines, amino acids, nitriles, and N-heterocycles have been obtained from a range of biomass feedstock either directly or via intermediate platform compounds. Two strategies to produce organonitrogen chemicals are presented. For platform chemicals derived from cellulose, hemicellulose, lignin, and lipids, which are enriched with oxygen functionalities, in particular, hydroxyl groups, the key chemistry to be developed is the catalytic transformation of hydroxyl groups into nitrogen-containing groups using NH3 as the nitrogen source. Along this line, Ru- and Ni-based heterogeneous catalysts are developed to convert alcohols to amines and/or nitriles via a thermal catalytic pathway, while CdS nanomaterials are explored to promote -OH to -NH2 conversion under visible-light irradiation. Metal-zeolite multifunctional systems are further established to enable the synthesis of N-heterocycles from O-heterocycles. The second strategy involves the use of chitin and chitin derivatives as the starting materials. Under the concept of shell biorefinery, distinctive protocols have been established to chemically transform chitin as the sole feedstock to amino sugars, amino alcohols, furanic amides, and N-heterocycles. By combining mechanochemistry with biotransformation, an integrated process to convert shrimp shell waste to complex, high-value, chiral compounds including tyrosine and l-DOPA is also demonstrated.


Assuntos
Aminas/metabolismo , Aminoácidos/metabolismo , Quitina/metabolismo , Nitrilas/metabolismo , Aminas/química , Aminoácidos/química , Biomassa , Quitina/química , Estrutura Molecular , Nitrilas/química
17.
Arch Toxicol ; 95(2): 395-472, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33459808

RESUMO

This is an overview of the metabolic activation of drugs, natural products, physiological compounds, and general chemicals by the catalytic activity of cytochrome P450 enzymes belonging to Families 1-4. The data were collected from > 5152 references. The total number of data entries of reactions catalyzed by P450s Families 1-4 was 7696 of which 1121 (~ 15%) were defined as bioactivation reactions of different degrees. The data were divided into groups of General Chemicals, Drugs, Natural Products, and Physiological Compounds, presented in tabular form. The metabolism and bioactivation of selected examples of each group are discussed. In most of the cases, the metabolites are directly toxic chemicals reacting with cell macromolecules, but in some cases the metabolites formed are not direct toxicants but participate as substrates in succeeding metabolic reactions (e.g., conjugation reactions), the products of which are final toxicants. We identified a high level of activation for three groups of compounds (General Chemicals, Drugs, and Natural Products) yielding activated metabolites and the generally low participation of Physiological Compounds in bioactivation reactions. In the group of General Chemicals, P450 enzymes 1A1, 1A2, and 1B1 dominate in the formation of activated metabolites. Drugs are mostly activated by the enzyme P450 3A4, and Natural Products by P450s 1A2, 2E1, and 3A4. Physiological Compounds showed no clearly dominant enzyme, but the highest numbers of activations are attributed to P450 1A, 1B1, and 3A enzymes. The results thus show, perhaps not surprisingly, that Physiological Compounds are infrequent substrates in bioactivation reactions catalyzed by P450 enzyme Families 1-4, with the exception of estrogens and arachidonic acid. The results thus provide information on the enzymes that activate specific groups of chemicals to toxic metabolites.


Assuntos
Ativação Metabólica , Produtos Biológicos/metabolismo , Sistema Enzimático do Citocromo P-450/fisiologia , Preparações Farmacêuticas/metabolismo , Xenobióticos/metabolismo , Aminas/química , Aminas/metabolismo , Produtos Biológicos/química , Hormônios/química , Hormônios/metabolismo , Humanos , Inseticidas/química , Inseticidas/metabolismo , Preparações Farmacêuticas/química , Hidrocarbonetos Policíclicos Aromáticos/química , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Xenobióticos/química
18.
Biochim Biophys Acta Biomembr ; 1863(9): 183547, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-33417968

RESUMO

Although widely used clinically, the mechanism underlying the action of local anesthetics remains elusive. Direct interaction of anesthetics with membrane proteins and modulation of membrane physical properties by anesthetics are plausible mechanisms proposed, although a combination of these two mechanisms cannot be ruled out. In this context, the role of G protein-coupled receptors (GPCRs) in local anesthetic action is a relatively new area of research. We show here that representative tertiary amine local anesthetics induce a reduction in two-dimensional diffusion coefficient of the serotonin1A receptor, an important neurotransmitter GPCR. The corresponding change in mobile fraction is varied, with tetracaine exhibiting the maximum reduction in mobile fraction, whereas the change in mobile fraction for other local anesthetics was not appreciable. These results are supported by quantitation of cellular F-actin, using a confocal microscopic approach previously developed by us, which showed that a pronounced increase in F-actin level was induced by tetracaine. These results provide a novel perspective on the action of local anesthetics in terms of GPCR lateral diffusion and actin cytoskeleton reorganization.


Assuntos
Citoesqueleto de Actina/metabolismo , Aminas/metabolismo , Anestésicos Locais/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Citoesqueleto de Actina/química , Aminas/química , Anestésicos Locais/química , Animais , Células CHO , Células Cultivadas , Cricetulus , Difusão , Estrutura Molecular , Receptores Acoplados a Proteínas G/química
19.
Nat Commun ; 12(1): 173, 2021 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-33420084

RESUMO

Bio-based production of many chemicals is not yet possible due to the unknown biosynthetic pathways. Here, we report a strategy combining retrobiosynthesis and precursor selection step to design biosynthetic pathways for multiple short-chain primary amines (SCPAs) that have a wide range of applications in chemical industries. Using direct precursors of 15 target SCPAs determined by the above strategy, Streptomyces viridifaciens vlmD encoding valine decarboxylase is examined as a proof-of-concept promiscuous enzyme both in vitro and in vivo for generating SCPAs from their precursors. Escherichia coli expressing the heterologous vlmD produces 10 SCPAs by feeding their direct precursors. Furthermore, metabolically engineered E. coli strains are developed to produce representative SCPAs from glucose, including the one producing 10.67 g L-1 of iso-butylamine by fed-batch culture. This study presents the strategy of systematically designing biosynthetic pathways for the production of a group of related chemicals as demonstrated by multiple SCPAs as examples.


Assuntos
Aminas/química , Aminas/metabolismo , Vias Biossintéticas , Engenharia de Proteínas , Vias Biossintéticas/genética , Carboxiliases/genética , Carboxiliases/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Fermentação , Glucose/metabolismo , Microbiologia Industrial , Engenharia Metabólica , Simulação de Acoplamento Molecular , Streptomyces/enzimologia , Streptomyces/genética , Streptomyces/metabolismo
20.
Food Chem ; 343: 128397, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33406569

RESUMO

Chocolate is an important source of free bioactive amines and amino acids which play important roles in human health. Considering the limited information on the bioaccessibility of these compounds from chocolate, the objective of this study was to characterize their profiles and bioaccessibility in 70% cocoa dark chocolate through in vitro simulation of oral, gastric and intestinal digestions. Seven amines were detected; polyamines were predominant before in vitro digestion, whereas tyramine, cadaverine and spermidine after digestion. All amines showed high bioaccessibility with slight influence of digestive enzymes. Amines increased after gastrointestinal digestion: tyramine (13-fold), tryptamine (9-fold), others (2.4-4.2-fold) and histamine appeared. All amino acids, GABA and ammonia were detected in chocolate, and their contents increased after in vitro digestion due to digestive enzymes (4.6, 2.8 and 2.1, respectively). Dark chocolate protein is a good source of tryptophan, phenylalanine + tyrosine, isoleucine, histidine, but limiting for lysine, leucine, and threonine.


Assuntos
Aminas/metabolismo , Aminoácidos/metabolismo , Cacau/metabolismo , Chocolate/análise , Aminas/análise , Aminoácidos/análise , Amônia/metabolismo , Cacau/química , Cromatografia Líquida de Alta Pressão , Análise por Conglomerados , Histamina/análise , Histamina/metabolismo , Humanos , Valor Nutritivo , Poliaminas/análise , Poliaminas/metabolismo , Análise de Componente Principal , Ácido gama-Aminobutírico/análise
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