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1.
In Vivo ; 34(5): 3023-3026, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32871846

RESUMO

BACKGROUND/AIM: Coronavirus disease 2019 (COVID-19) is an infectious disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). One drug that has attracted interest is the antiparasitic compound ivermectin, a macrocyclic lactone derived from the bacterium Streptomyces avermitilis. We carried out a docking study to determine if ivermectin might be able to attach to the SARS-CoV-2 spike receptor-binding domain bound with ACE2. MATERIALS AND METHODS: We used the program AutoDock Vina Extended to perform the docking study. RESULTS: Ivermectin docked in the region of leucine 91 of the spike and histidine 378 of the ACE2 receptor. The binding energy of ivermectin to the spike-ACE2 complex was -18 kcal/mol and binding constant was 5.8 e-08. CONCLUSION: The ivermectin docking we identified may interfere with the attachment of the spike to the human cell membrane. Clinical trials now underway should determine whether ivermectin is an effective treatment for SARS-Cov2 infection.


Assuntos
Betacoronavirus/efeitos dos fármacos , Infecções por Coronavirus/tratamento farmacológico , Ivermectina/química , Peptidil Dipeptidase A/química , Pneumonia Viral/tratamento farmacológico , Betacoronavirus/química , Betacoronavirus/patogenicidade , Sítios de Ligação/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Infecções por Coronavirus/virologia , Reposicionamento de Medicamentos , Histidina/química , Humanos , Ivermectina/uso terapêutico , Leucina/química , Simulação de Acoplamento Molecular , Pandemias , Peptidil Dipeptidase A/efeitos dos fármacos , Pneumonia Viral/virologia , Streptomyces/química
2.
Bioresour Technol ; 315: 123845, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32707504

RESUMO

The main aim of this work was to study the allethrin binding interactions with esterase and its bioremediation potential using an isolated bacterial strain CW7, identified as Pseudomonas nitroreducens. The degradation conditions with strain CW7 were optimized using response surface methodology at pH 7.0, a temperature of 32 °C, and an inocula concentration of 150 mg·L-1, with 96% allethrin degradation observed over 7 days. The kinetic parameters qmax, Ks, and Ki were calculated to be 0.512 day-1, 4.97 mg·L-1, and 317.13 mg·L-1, respectively. Nine intermediate metabolites were identified after analysing the degradation products by gas chromatography-mass spectrometry. Strain CW7 effectively degraded a wide variety of pyrethroids as a carbon source. Molecular modeling, docking, and enzyme kinetics were used to investigate the binding pocket of the esterase containing amino acids such as alanine, arginine, valine, proline, cysteine, glycine, isoleucine, phenylalanine, serine, asparagine, and threonine, which play active roles in allethrin degradation.


Assuntos
Aletrinas , Histidina , Alanina , Arginina , Biodegradação Ambiental , Esterases , Glutamatos , Leucina , Lisina , Metionina , Pseudomonas , Serina , Tirosina
3.
Zhonghua Yi Xue Za Zhi ; 100(25): 1947-1951, 2020 Jul 07.
Artigo em Chinês | MEDLINE | ID: mdl-32629594

RESUMO

Objective: To analyze the differences of clinical characteristics and outcomes between relapsing and monophasic patients with anti-leucine-rich glioma-inactivated 1 (anti-LGI1) encephalitis. Methods: Medical records of confirmed anti-LGI1 encephalitic patients who underwent immunotherapy were retrospectively collected from January 2015 to January 2019 in the first affiliated hospital of Zhengzhou University. Clinical data, treatment methods, duration of treatment and outcomes were analyzed between the relapsing and monophasic groups. Results: Among the 33 anti-LGI1 encephalitic patients, there were 12 and 21 cases in the relapsing and monophasic groups, respectively. No difference was found in age, sex, precipitating factors, intensive care unit (ICU) admission, symptoms and modified Rankin Scale (mRS) score in the acute phase (P>0.05). As to the lab test and image examination, no statistic difference was found in serum and cerebral spinal fluid (CSF) positive rate, hyponatremia, abnormal rate of electrocardiogram (ECG), electroencephalogram (EEG), CSF and magnetic resonance imaging (MRI) and lesion locations (P>0.05). No difference was found in time to diagnose the disease between the 2 groups (P>0.05). The median immunotherapy period was 102.5 days in relapsing group and 194.0 days in monophasic group, with a statistic difference (P=0.001). No patients had bad outcomes in the monophasic group at the last follow-up, while 6 patients had poor outcomes in the relapsing group (4 patients died). The patients in relapsing group had a worse prognosis compared to those in the monophasic group (P=0.007). Conclusions: Relapse is common in anti-LGI1 encephalitis. Patients in the relapsing group received a shorter term of immunotherapy and had worse outcomes than those in the monophasic group.


Assuntos
Encefalite , Glioma , Autoanticorpos , Humanos , Leucina , Recidiva Local de Neoplasia , Estudos Retrospectivos
4.
J Clin Pediatr Dent ; 44(3): 174-179, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32644890

RESUMO

Objective: The aim of the present study was to evaluate the reduction in bacterial loading using Papacarie and Carisolv as an irrigating solution in pulpectomized primary molars. Study design: A controlled, randomized clinical trial involving 120 necrotic canals from both genders between 3 and 7 years old children were included, 30 irrigated with Papacarie [ group I], Carisolv [ group II], 1% NaOCl gel [ group III] and 1% Na0Cl solution [group IV ] each; in all cases, 2 microbiological samples from within the canals were taken with sterile paper points, the first after the canal opening and before the first irrigation, and the second after instrumentation and final irrigation, before obturation. All samples were evaluated by Agar plate method. Results: The results were statistically analyzed by ANOVA. After analyzing samples before and after irrigation in all the groups, a strong significant decrease in bacterial load [ p = < 0.001 ] was found with Papacarie and Carisolv. Conclusion: Papacarie and Carisolv can be suggested as an alternative irrigant for pulpectomy of necrotic teeth.


Assuntos
Dente Molar , Irrigantes do Canal Radicular , Criança , Pré-Escolar , Cavidade Pulpar , Feminino , Ácido Glutâmico , Humanos , Leucina , Lisina , Masculino , Papaína , Preparo de Canal Radicular , Hipoclorito de Sódio
5.
Sci Total Environ ; 736: 139678, 2020 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-32479959

RESUMO

A father's lifetime experience is a major risk factor for a range of diseases in an individual, and the consequences of the exposure can also be transmitted to his offspring. Our previous work has demonstrated that damage to testicular structures and decline in sperm quality in male mice can be caused by microcystin-leucine arginine (MC-LR), but the overall effects of the scope and extent of paternal exposure on health and disease in the offspring remain underexplored. Here, we report that MC-LR-paternal-exposed offspring mice showed reduced litter size and body weight accompanied by increased abnormalities in the lung. Analyses of the small noncoding RNAs (sncRNAs) in the sperm from MC-LR-exposed males demonstrated the downregulation of a wide range of piRNAs enriched for those target genes involved in the regulation of the embryo implantation pathways. Gene and protein expression analyses, as well as biochemical and functional studies, revealed suppressed expression of Hsp90α in testicular tissues from MC-LR-exposed males. Decreased Hsp90α in testicular tissues impaired the development of the offspring. In this study, we revealed that MC-LR alters the expression of Hsp90α in testicular tissues to cause changes in the expression profiles of sperm piRNAs produced by paternal mice. These changes lead to aberrant activation of the Wnt/ß-catenin signaling pathway in pulmonary tissues of offspring mice, causing lung tissue damage and abnormal development. We hereby confirmed that MC-LR-induced alterations in epigenetic inheritance are capable of contributing to intergenerational developmental defects in paternal-exposed offspring mice.


Assuntos
Arginina , Microcistinas , Animais , Pai , Humanos , Leucina , Masculino , Camundongos , Camundongos Endogâmicos BALB C
6.
Sci Total Environ ; 740: 139917, 2020 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-32563870

RESUMO

Ambient ammonia exposure has been known to perturb lipid metabolism in farm animals, but the underlying mechanism is unclear. The current study was conducted to investigate how ambient ammonia exposure influences lipid metabolism in the pig model. Twelve pigs were randomly divided into two groups, either exposed to 0 or 35 mg/m3 atmospheric ammonia for 25 days. Serum ammonia remained unchanged (p > 0.05), but increased serum urea concentration was found (p < 0.05) after ammonia exposure. Ammonia exposure also caused an increased C18:0, C18:2n6c, C18:3n6, C18:3n3, C20:0, C20:2, C20:3n6, C20:3n3, C22:0 concentrations and fat content in the longissimus dorsi muscle (p < 0.05), and also serum total triglyceride (p = 0.0294) and ApoB (p = 0.0061) contents. Analysis of serum free amino acids profile revealed that concentrations of ornithine, tyrosine, asparagine, histidine, phenylalanine, leucine, isoleucine, glutamine and valine were significantly increased in the pigs exposed to 35 mg/m3 ammonia (p < 0.05). RNA-Seq analysis showed that genes encoding enzymes involved in lipid synthesis (FASN, SCD and FADS1) and uptake (LDLR) were up-regulated, whereas genes related to lipolysis (PNPLA4, ANGPTL4 and CEL), transport (CPT1A, CPT1B and CPT2) and ß-oxidation (ACADL, ACADVL, UCP2 and UCP3) were down-regulated. Furthermore, exposure to 35 mg/m3 atmospheric ammonia increased expression of mTOR (p = 0.0377) and its downstream P70S6K (p = 0.0139) and p-P70S6K (p = 0.0431), but decreased AMPK (p < 0.0001) and p-AMPK (p = 0.0071) in the longissimus dorsi muscle. In conclusion, high concentration of atmospheric ammonia exposure greatly interferes with amino acid metabolism, resulting in increased BCAAs and aromatic amino acids. The increased BCAAs production can up-regulate lipid synthesis and down-regulate ß-oxidation by activating mTOR signaling and inhibiting AMPK signaling.


Assuntos
Amônia , Metabolismo dos Lipídeos , Músculo Esquelético/metabolismo , Suínos/metabolismo , Amônia/sangue , Amônia/farmacologia , Animais , Leucina , Metabolismo dos Lipídeos/efeitos dos fármacos , Serina-Treonina Quinases TOR
7.
Medicine (Baltimore) ; 99(22): e20372, 2020 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-32481420

RESUMO

The present study investigated the effectiveness of a Carisolv III + 0.5% sodium hypochlorite (NaOCl)-based root canal irrigant for smear layer removal.Forty maxillary incisors were randomly divided into 4 groups (n = 10 per group). The canals in group A (experimental) were prepared with 0.5% NaOCl, and Carisolv III and 0.5% NaOCl was used for the final washing; groups B and C (positive controls) used 2% and 5.25% NaOCl, respectively; and group D (negative control) used phosphate-buffered saline (PBS). Ethylenediaminetetraacetic acid (EDTA) was used for all of the groups. A 5-point scoring scale and scanning electron microscopy were used to evaluate the effectiveness of the irrigants. The canals were consistently cleaner in the coronal and middle thirds than in the apical thirds (P < .05).For cleaning the root canals, 5.25% NaOCl was more effective than 2% NaOCl, 0.5% NaOCl + Carisolv III, and phosphate-buffered saline , respectively (P < .05). The 2% NaOCl solution showed similar results to 0.5% NaOCl + Carisolv III (P > .05). The combination of 5.25% NaOCl and 17% EDTA remains the most effective irrigant for removal of the root canal smear layer.A combination of Carisolv III + 0.5% NaOCl (with 17% EDTA) showed a cleaning ability similar to that of 2% NaOCl (with 17% EDTA).


Assuntos
Ácido Glutâmico/uso terapêutico , Leucina/uso terapêutico , Lisina/uso terapêutico , Irrigantes do Canal Radicular/uso terapêutico , Tratamento do Canal Radicular/métodos , Hipoclorito de Sódio/uso terapêutico , Adulto , Cavidade Pulpar/cirurgia , Feminino , Humanos , Técnicas In Vitro , Incisivo/cirurgia , Masculino , Pessoa de Meia-Idade
8.
Nat Commun ; 11(1): 3148, 2020 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-32561715

RESUMO

Macroautophagy ("autophagy") is the main lysosomal catabolic process that becomes activated under nutrient-depleted conditions, like amino acid (AA) starvation. The mechanistic target of rapamycin complex 1 (mTORC1) is a well-conserved negative regulator of autophagy. While leucine (Leu) is a critical mTORC1 regulator under AA-starved conditions, how Leu regulates autophagy is poorly understood. Here, we describe that in most cell types, including neurons, Leu negatively regulates autophagosome biogenesis via its metabolite, acetyl-coenzyme A (AcCoA). AcCoA inhibits autophagy by enhancing EP300-dependent acetylation of the mTORC1 component raptor, with consequent activation of mTORC1. Interestingly, in Leu deprivation conditions, the dominant effects on autophagy are mediated by decreased raptor acetylation causing mTORC1 inhibition, rather than by altered acetylation of other autophagy regulators. Thus, in most cell types we examined, Leu regulates autophagy via the impact of its metabolite AcCoA on mTORC1, suggesting that AcCoA and EP300 play pivotal roles in cell anabolism and catabolism.


Assuntos
Autofagia/fisiologia , Leucina/metabolismo , Proteína Regulatória Associada a mTOR/metabolismo , Acetilcoenzima A/metabolismo , Acetilação , Animais , Autofagossomos , Linhagem Celular , Proteína p300 Associada a E1A/metabolismo , Humanos , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Camundongos , Cultura Primária de Células , Inanição/metabolismo
9.
Nat Commun ; 11(1): 2847, 2020 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-32504036

RESUMO

The browning of white adipose tissue (WAT) has got much attention for its potential beneficial effects on metabolic disorders, however, the nutritional factors and neuronal signals involved remain largely unknown. We sought to investigate whether WAT browning is stimulated by leucine deprivation, and whether the amino acid sensor, general control non-derepressible 2 (GCN2), in amygdalar protein kinase C-δ (PKC-δ) neurons contributes to this regulation. Our results show that leucine deficiency can induce WAT browning, which is unlikely to be caused by food intake, but is largely blocked by PKC-δ neuronal inhibition and amygdalar GCN2 deletion. Furthermore, GCN2 knockdown in amygdalar PKC-δ neurons blocks WAT browning, which is reversed by over-expression of amino acid responsive gene activating transcription factor 4 (ATF4), and is mediated by the activities of amygdalar PKC-δ neurons and the sympathetic nervous system. Our data demonstrate that GCN2/ATF4 can regulate WAT browning in amygdalar PKC-δ neurons under leucine deprivation.


Assuntos
Fator 4 Ativador da Transcrição/metabolismo , Tecido Adiposo Branco/fisiologia , Tonsila do Cerebelo/fisiologia , Leucina/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Tecido Adiposo Marrom/fisiologia , Tecido Adiposo Branco/inervação , Tonsila do Cerebelo/citologia , Animais , Técnicas de Silenciamento de Genes , Lipólise/fisiologia , Masculino , Camundongos , Camundongos Knockout , Neurônios/metabolismo , Proteína Quinase C-delta/metabolismo , Proteínas Serina-Treonina Quinases/genética , Transdução de Sinais/fisiologia , Técnicas Estereotáxicas , Sistema Nervoso Simpático/fisiologia , Termogênese/fisiologia
10.
Am J Physiol Cell Physiol ; 318(6): C1284-C1293, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32320287

RESUMO

The present study aimed to elucidate the mechanisms by which leucine impacts the secretion of pancreatic enzymes, especially amylase, by studying the proteomics profiles of pancreatic acinar (PA) cells from dairy cows. PA cells, the experimental model, were treated with four concentrations of leucine (0, 0.23, 0.45, and 0.90 mM). The abundance of different proteins in the four leucine treatment groups was detected. Label-free proteomic analysis enabled the identification of 1,906 proteins in all four treatment groups, and 1,350 of these proteins showed common expression across the groups. The primary effects of leucine supplementation were increased (P < 0.05) citrate synthase and ATPase activity, which enlarged the cytosolic ATP pool, and the upregulation of secretory protein 61 (Sec61) expression, which promoted protein secretion. In summary, these results suggest that leucine increases citrate synthase in the TCA cycle and ATPase activity and promotes the Sec signaling pathway to increase the exocrine function of PA cells.


Assuntos
Células Acinares/efeitos dos fármacos , Ciclo do Ácido Cítrico/efeitos dos fármacos , Leucina/farmacologia , Pâncreas Exócrino/efeitos dos fármacos , Via Secretória/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , alfa-Amilases/metabolismo , Células Acinares/enzimologia , Trifosfato de Adenosina/metabolismo , Animais , Animais Recém-Nascidos , Bovinos , Células Cultivadas , Citrato (si)-Sintase/metabolismo , Indústria de Laticínios , Masculino , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Pâncreas Exócrino/enzimologia , Proteômica , Canais de Translocação SEC/metabolismo
11.
J Environ Manage ; 262: 110304, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32250788

RESUMO

Atrazine, is one of major concern pesticides contaminating agricultural areas and ground water. Its microbial biodegradation seems to be the most efficient in terms of economic and environmental benefits. In the present work the cometabolic biodegradation of atrazine by the fungus Metarhizum robertsii IM 6519 during 10-day batch cultures was characterized. The herbicide was transformed to several hydroxy-, dechlorinated or dealkylated metabolites with the involvement of cytochrome P450 monooxygenases. The obtained metabolomics data revealed that atrazine induced oxidative stress (increased the levels of L-proline, L-ornithine, L-arginine, GABA and L-methionine), disruptions of the carbon and nitrogen metabolism (L-aspartic acid, L-asparagine, L-tyrosine, L-threonine, L-isoleucine, L-phenylalanine, 1-methyl-L-histidine, L-tryptophan, L-valine, L-alanine, O-phospho-L-serine, L-sarcosine or L-lysine) and caused an increase in the membrane fluidity (a rise in the phosphatidylcholines/phosphatidylethanolamines (PC/PE) ratio together with the growth of the taurine level). The increased level of hydroxyl derivatives of linoleic acid (9-HODE and 13-HODE) confirmed that atrazine induced lipid peroxidation. The presented results suggesting that M. robertsii IM 6519 might be applied in atrazine biodegradation and may bring up the understanding of the process of triazine biodegradation by Metarhizum strains.


Assuntos
Atrazina , Metarhizium , Alanina , Aminoácidos , Cistina , Glutamatos , Glicina , Histidina , Leucina , Lipídeos
12.
Water Res ; 177: 115803, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32302809

RESUMO

Previous studies have focused on investigating the formation of odorous by-products during the chlorination of free amino acids (AAs). However, studies on the formation of odorous by-products during the chlorination of combined AAs, which are much more abundant in natural waters than free AAs, are very limited. In this study, the generation of odorous aldehyde, nitrile and N-chloroaldimine from short oligopeptides containing combined Leucine (Leu) (a typical precursor of odorous by-products), including glycylleucine (Gly-Leu), leucylglycine (Leu-Gly), and trileucine (Leu-Leu-Leu), was investigated. The reaction mechanisms were then proposed based on Acquity UPLC-qTOF mass spectrometer measurement and kinetic studies modelled with Kintecus. The results indicated that a series of sequential reactions, including substitution, dehydrohalogenation, ß-elimination, hydrolysis and decarboxylation reactions, occurred during the chlorination of short oligopeptides. The chlorination of Gly-Leu and Leu-Leu-Leu formed free Leu, which continued to react with chlorine, producing isovaleraldehyde, isovaleronitrile and N-chloroisovaleraldimine. Compared with Gly-Leu, Leu-Leu-Leu produced less free Leu, and therefore, a smaller amount of Leu-derived odorous by-products was generated. Leu-Gly produced free Gly, which was not a precursor of odorous by-products. Thus, neither isovaleraldehyde nor N-chloroisovaleraldimine was formed. Notably, isovaleronitriles can be formed directly from a ß-elimination reaction during chlorination of Leu-Gly and Leu-Leu-Leu, and thus high yields of isovaleronitriles were observed after chlorination. The yields of odorous by-products during chlorination of short oligopeptides increased with increasing Cl/N ratios (the molar ratio of chlorine to nitrogen in the AAs) and reached their maximum at Cl/N = 2.4, except the yield of isovaleraldehyde formed from Gly-Leu reached its maximum at Cl/N = 1.6. UV and UV/H2O2 pre-treatments decreased odorous by-product formation during subsequent chlorination through non-peptide bond breaking of short oligopeptides. This study facilitates the identification of the causes of off-flavour problems in drinking water and the development of ways to control these problems.


Assuntos
Desinfetantes , Poluentes Químicos da Água , Purificação da Água , Aldeídos , Cloro , Desinfecção , Halogenação , Peróxido de Hidrogênio , Cinética , Leucina , Nitrilos , Oligopeptídeos
13.
Anticancer Res ; 40(4): 1833-1841, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32234871

RESUMO

BACKGROUND/AIM: Time-restricted feeding (TRF) during the dark phase of the day restores metabolic homeostasis in mice. MATERIALS AND METHODS: We performed untargeted metabolomic analysis on plasma from mice subjected to TRF that attenuates high-fat diet-enhanced spontaneous metastasis of Lewis lung carcinoma (LLC). RESULTS: Twenty-four of 152 identified metabolites differed among the four dietary groups (non-LLC-bearing mice fed the AIN93G diet and LLC-bearing mice fed the AIN93G, the high-fat diet (HFD), or TRF of the HFD). Component 1 of sparse partial least squares-discriminant analysis showed a clear separation between non-LLC-bearing and LLC-bearing mice. Major metabolites responsible for the changes were elevations in α-tocopherol, docosahexaenoic acid, cholesterol, dihydrocholestrol, isoleucine, leucine, and phenylalanine and decreases in lactic acid and pyruvic acid in LLC-bearing mice particularly those fed the HFD. Time-restricted feeding shifted the metabolic profile of LLC-bearing mice towards that of non-LLC-bearing controls. CONCLUSION: Time-restricted feeding improves metabolic profile of LLC-bearing mice.


Assuntos
Carcinoma Pulmonar de Lewis/sangue , Jejum/sangue , Metabolômica , Animais , Carcinoma Pulmonar de Lewis/dietoterapia , Colestanol/sangue , Colesterol/sangue , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Ácidos Docosa-Hexaenoicos/sangue , Jejum/fisiologia , Humanos , Insulina/sangue , Isoleucina/sangue , Ácido Láctico/sangue , Leucina/sangue , Camundongos , Metástase Neoplásica , Fenilalanina/sangue , Ácido Pirúvico/sangue , alfa-Tocoferol/sangue
14.
Cell ; 181(2): 271-280.e8, 2020 04 16.
Artigo em Inglês | MEDLINE | ID: covidwho-4561

RESUMO

The recent emergence of the novel, pathogenic SARS-coronavirus 2 (SARS-CoV-2) in China and its rapid national and international spread pose a global health emergency. Cell entry of coronaviruses depends on binding of the viral spike (S) proteins to cellular receptors and on S protein priming by host cell proteases. Unravelling which cellular factors are used by SARS-CoV-2 for entry might provide insights into viral transmission and reveal therapeutic targets. Here, we demonstrate that SARS-CoV-2 uses the SARS-CoV receptor ACE2 for entry and the serine protease TMPRSS2 for S protein priming. A TMPRSS2 inhibitor approved for clinical use blocked entry and might constitute a treatment option. Finally, we show that the sera from convalescent SARS patients cross-neutralized SARS-2-S-driven entry. Our results reveal important commonalities between SARS-CoV-2 and SARS-CoV infection and identify a potential target for antiviral intervention.


Assuntos
Betacoronavirus/metabolismo , Infecções por Coronavirus/tratamento farmacológico , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/tratamento farmacológico , Inibidores de Proteases/farmacologia , Serina Endopeptidases/metabolismo , Glicoproteína da Espícula de Coronavírus/metabolismo , Internalização do Vírus/efeitos dos fármacos , Cloreto de Amônio/farmacologia , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Betacoronavirus/química , Betacoronavirus/genética , Linhagem Celular , Coronavirus/química , Coronavirus/genética , Coronavirus/fisiologia , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/terapia , Desenvolvimento de Medicamentos , Gabexato/análogos & derivados , Gabexato/farmacologia , Humanos , Imunização Passiva , Leucina/análogos & derivados , Leucina/farmacologia , Pandemias , Peptidil Dipeptidase A/química , Receptores Virais/química , Receptores Virais/metabolismo , Vírus da SARS/fisiologia , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Vesiculovirus/genética
15.
Cell ; 181(2): 271-280.e8, 2020 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-32142651

RESUMO

The recent emergence of the novel, pathogenic SARS-coronavirus 2 (SARS-CoV-2) in China and its rapid national and international spread pose a global health emergency. Cell entry of coronaviruses depends on binding of the viral spike (S) proteins to cellular receptors and on S protein priming by host cell proteases. Unravelling which cellular factors are used by SARS-CoV-2 for entry might provide insights into viral transmission and reveal therapeutic targets. Here, we demonstrate that SARS-CoV-2 uses the SARS-CoV receptor ACE2 for entry and the serine protease TMPRSS2 for S protein priming. A TMPRSS2 inhibitor approved for clinical use blocked entry and might constitute a treatment option. Finally, we show that the sera from convalescent SARS patients cross-neutralized SARS-2-S-driven entry. Our results reveal important commonalities between SARS-CoV-2 and SARS-CoV infection and identify a potential target for antiviral intervention.


Assuntos
Betacoronavirus/metabolismo , Infecções por Coronavirus/tratamento farmacológico , Peptidil Dipeptidase A/metabolismo , Pneumonia Viral/tratamento farmacológico , Inibidores de Proteases/farmacologia , Serina Endopeptidases/metabolismo , Glicoproteína da Espícula de Coronavírus/metabolismo , Internalização do Vírus/efeitos dos fármacos , Cloreto de Amônio/farmacologia , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Betacoronavirus/química , Betacoronavirus/genética , Linhagem Celular , Coronavirus/química , Coronavirus/genética , Coronavirus/fisiologia , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/terapia , Desenvolvimento de Medicamentos , Gabexato/análogos & derivados , Gabexato/farmacologia , Humanos , Imunização Passiva , Leucina/análogos & derivados , Leucina/farmacologia , Pandemias , Peptidil Dipeptidase A/química , Receptores Virais/química , Receptores Virais/metabolismo , Vírus da SARS/fisiologia , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Vesiculovirus/genética
16.
Food Chem ; 320: 126619, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32203836

RESUMO

The fermentation of mare's milk into koumiss produces many beneficial functional compounds depending on the metabolism of the initial microbial flora. In this study, metabolites found in mare's milk and resulting koumiss were identified. Major metabolic pathways in the fermentation were also identified using an UPLC-Q-TOF-MS-based metabolomics method. In total, 354 metabolites were identified: 61 were up-regulated and 105 were down-regulated. Metabolic pathway analyses revealed that c-5-branched dibasic acid metabolism, valine, leucine and isoleucine degradation, arginine and proline metabolism, valine, leucine and isoleucine biosynthesis, vascular smooth muscle contraction, aminoacyl-tRNA biosynthesis and ß-alanine metabolism showed significant increases. A hierarchical cluster analysis of metabolites indicated a clear grouping pattern in which the relative concentrations of p-pyruvate, 20-HETE, 4-aminobutanoate, uracil, acetoacetate, and γ-linolenic acid differed significantly between milk and koumiss. This study provides reference values for metabolic isolates and bioactive compounds purification in mare's milk and koumiss.


Assuntos
Kumis/análise , Metabolômica , Leite/química , Animais , Arginina/química , Arginina/metabolismo , Cromatografia Líquida de Alta Pressão , Feminino , Fermentação , Cavalos , Leucina/química , Leucina/metabolismo , Espectrometria de Massas , Leite/metabolismo , Valina/química , Valina/metabolismo
17.
Food Chem ; 319: 126514, 2020 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-32179369

RESUMO

Caseins and whey proteins are known as 'slow' and 'fast' proteins, respectively, based on their amino acid absorption rate. However, there is limited understanding of the mechanisms controlling their behaviour during gastro-intestinal transit. A protein model system (8% total protein) with varying casein:whey protein ratios (0:100, 20:80, 50:50 and 80:20) were subjected to in vitro gastro-intestinal digestion using a semi-dynamic gastric model, a static intestinal model and an ex vivo absorption model (Ussing chambers). The casein-rich (≥50%) samples showed the formation of solid coagula that were persistent throughout gastric digestion, which caused a delay in nutrient emptying, slower digestion and leucine absorption kinetics. In contrast, whey proteins formed more soluble aggregates during the gastric phase, which led to faster gastric emptying, rapid intestinal hydrolysis, and higher and faster leucine absorption. This work shows the key role of the gastric restructuring for the overall digestive mechanism and kinetics of food, in particular proteins.


Assuntos
Caseínas/química , Lipídeos/química , Proteínas do Soro do Leite/química , Animais , Digestão , Feminino , Esvaziamento Gástrico , Hidrólise , Leucina/química , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Estômago
18.
Am J Physiol Regul Integr Comp Physiol ; 318(4): R790-R798, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32160019

RESUMO

The fatty acid, lauric acid (C12), and the amino acid, leucine (Leu) stimulate gut hormones, including CCK, associated with suppression of energy intake. In our recent study, intraduodenal infusion of a combination of C12 and l-tryptophan, at loads that individually did not affect energy intake, reduced energy intake substantially, associated with much greater stimulation of CCK. We have now investigated whether combined administration of C12 and Leu would enhance the intake-suppressant effects of each nutrient, when given at loads that each suppress energy intake individually. Sixteen healthy, lean males (age: 23 ± 2 yr) received, in randomized, double-blind fashion, 90-min intraduodenal infusions of control (saline), C12 (0.4 kcal/min), Leu (0.45 kcal/min), or C12+Leu (0.85 kcal/min). Antropyloroduodenal pressures were measured continuously and plasma CCK at 15-min intervals, and energy intake from a standardized buffet-meal, consumed immediately postinfusion, was quantified. All nutrient infusions stimulated plasma CCK compared with control (P < 0.05). Moreover, C12 and C12+Leu stimulated CCK compared with Leu (P < 0.05) (mean concentration, pmol/L; control: 2.3 ± 0.3, C12: 3.8 ± 0.3, Leu: 2.7 ± 0.3, and C12+Leu: 4.0 ± 0.4). C12+Leu, but not C12 or Leu, stimulated pyloric pressures (P < 0.05). C12+Leu and C12 reduced energy intake (P < 0.05), and there was a trend for Leu to reduce (P = 0.06) energy intake compared with control, with no differences between the three nutrient treatments (kcal; control: 1398 ± 84, C12: 1226 ± 80, Leu: 1260 ± 92, and C12+Leu: 1208 ± 83). In conclusion, combination of C12 and Leu, at the loads given, did not reduce energy intake beyond their individual effects, possibly because maximal effects had been evoked.


Assuntos
Colecistocinina/sangue , Ingestão de Energia , Motilidade Gastrointestinal/efeitos dos fármacos , Ácidos Láuricos/farmacologia , Leucina/farmacologia , Adolescente , Adulto , Apetite/efeitos dos fármacos , Método Duplo-Cego , Ingestão de Alimentos/efeitos dos fármacos , Humanos , Ácidos Láuricos/administração & dosagem , Leucina/administração & dosagem , Masculino , Adulto Jovem
19.
Environ Toxicol ; 35(8): 822-830, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32170997

RESUMO

Microcystin-leucine arginine (MC-LR) is a cyclic heptapeptide hepatotoxin produced by cyanobacteria. MicroRNA-122 (miR-122) is specifically expressed in the liver. This study focuses on the role of miR-122 in MC-LR-induced dysregulation of hepatic iron homeostasis in C57BL/6 mice. The thirty mice were randomly divided into five groups (Control, 12.5 µg/kg·BW MC-LR, 25 µg/kg·BW MC-LR, Negative control agomir and 25 µg/kg·BW MC-LR + miR-122 agomir). The results show that MC-LR decreases the expressions of miR-122, Hamp, and its related regulators, while increasing the content of hepatic iron and the expressions of FPN1 and Tmprss6. Furthermore, miR-122 agomir pretreatment improves MC-LR induced dysregulation of hepatic iron homeostasis by arousing the related regulators and reducing the expression of Tmprss6. These results suggest that miR-122 agomir can prevent the accumulation of hepatic iron induced by MC-LR, which may be related to the regulation of hepcidin by BMP/SMAD and IL-6/STAT signaling pathways.


Assuntos
Microcistinas/toxicidade , Testes de Toxicidade , Animais , Arginina , Hepcidinas , Homeostase , Ferro , Leucina , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/metabolismo
20.
Int J Nanomedicine ; 15: 1397-1408, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32184594

RESUMO

Background: siRNA-mediated polo-like kinase 1 (PLK1) silencing has been proposed as a promising therapeutic method for multiple cancers. However, the clinic application of this method is still hindered by the low specific delivery of siPLK1 to desired tumor lesions. Herein, folate (FA)-modified and leucine-bearing polyethylenimine was successfully synthesized and showed excellent targeted silencing to folate receptor overexpressed cells. Materials and Methods: The condensation of siPLK1 by FA-N-Ac-L-Leu-PEI (NPF) was detected by the gel retardation assay. The targeted and silencing efficiency was evaluated by flow cytometry and confocal laser scanning microscope. The PLK1 expressions at gene or protein levels were detected by quantitative real-time PCR and Western blotting assay. Further impacts of the PLK1 silencing on cell viability, cell cycle, migration, and invasion were studied by MTT, colony formation, wound healing and transwell assays. Results: The NPF and siPLK1 could efficiently assemble to stable nanoparticles at a weight ratio of 3.0 and showed excellent condensation and protection effect. Owing to the FA-mediated targeted delivery, the uptake and silencing efficiency of NPF/siPLK1 to SGC-7901 cells was higher than that without FA modification. Moreover, NPF-mediated PLK1 silencing showed significant antitumor activity in vitro. The anti-proliferation effect of PLK1 silencing was induced via the mitochondrial-dependent apoptosis pathway with the cell cycle arrest of 45% at G2 phase and the apoptotic ratio of 28.3%. Conclusion: FA-N-Ac-L-Leu-PEI (NPF) could generate targeted delivery siPLK1 to FA receptor overexpressed cells and dramatically downregulate the expression of PLK1 expression.


Assuntos
Proteínas de Ciclo Celular/genética , Ácido Fólico/química , Técnicas de Transferência de Genes , Polietilenoimina/química , Proteínas Serina-Treonina Quinases/genética , Proteínas Proto-Oncogênicas/genética , Neoplasias Gástricas/terapia , Células A549 , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/genética , Linhagem Celular Tumoral , Sobrevivência Celular/genética , Ácido Fólico/farmacologia , Inativação Gênica , Terapia Genética/métodos , Humanos , Leucina/química , Nanopartículas/química , RNA Interferente Pequeno/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia
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