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1.
ACS Infect Dis ; 10(3): 928-937, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38334357

RESUMO

Clostridioides difficile causes life-threatening diarrhea and is one of the leading causes of nosocomial infections. During infection, C. difficile releases two gut-damaging toxins, TcdA and TcdB, which are the primary determinants of disease pathogenesis and are important therapeutic targets. Once in the cytosol of mammalian cells, TcdA and TcdB use UDP-glucose to glucosylate host Rho GTPases, which leads to cytoskeletal changes that result in a loss of intestinal integrity. Isofagomine inhibits TcdA and TcdB as a mimic of the glucocation transition state of the glucosyltransferase reaction. However, sequence variants of TcdA and TcdB across the clades of infective C. difficile continue to be identified, and therefore, evaluation of isofagomine inhibition against multiple toxin variants is required. Here, we show that isofagomine inhibits the glucosyltransferase domain of multiple TcdB variants and protects TcdB-induced cell rounding of the most common full-length toxin variants. Furthermore, we demonstrate that isofagomine protects against C. difficile-induced mortality in two murine models of C. difficile infection. Isofagomine treatment of mouse C. difficile infection also permitted the recovery of the gastrointestinal microbiota, an important barrier to preventing recurring C. difficile infection. The broad specificity of isofagomine supports its potential as a prophylactic to protect against C. difficile-induced morbidity and mortality.


Assuntos
Toxinas Bacterianas , Compostos de Boro , Clostridioides difficile , Imino Piranoses , Animais , Camundongos , Toxinas Bacterianas/genética , Enterotoxinas , Clostridioides difficile/genética , Proteínas de Bactérias/genética , Glucosiltransferases/genética , Mamíferos
2.
PLoS One ; 16(4): e0250513, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33886681

RESUMO

Fructose-6-phosphate aldolase (FSA) is an important enzyme for the C-C bond-forming reactions in organic synthesis. The present work is focused on the synthesis of a precursor of D-fagomine catalyzed by a mutant FSA. The biocatalyst has been immobilized onto several supports: magnetic nanoparticle clusters (mNC), cobalt-chelated agarose (Co-IDA), amino-functionalized agarose (MANA-agarose) and glyoxal-agarose, obtaining a 29.0%, 93.8%, 89.7% and 53.9% of retained activity, respectively. Glyoxal-agarose FSA derivative stood up as the best option for the synthesis of the precursor of D-fagomine due to the high reaction rate, conversion, yield and operational stability achieved. FSA immobilized in glyoxal-agarose could be reused up to 6 reaction cycles reaching a 4-fold improvement in biocatalyst yield compared to the non-immobilized enzyme.


Assuntos
Aldeído Liases/química , Enzimas Imobilizadas/química , Imino Piranoses/química , Nanopartículas de Magnetita/química , Aldeído Liases/metabolismo , Catálise , Cobalto/química , Enzimas Imobilizadas/metabolismo , Escherichia coli/enzimologia , Frutosefosfatos/metabolismo , Imino Piranoses/síntese química , Sefarose/química
3.
Commun Biol ; 4(1): 280, 2021 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-33664385

RESUMO

Irinotecan inhibits cell proliferation and thus is used for the primary treatment of colorectal cancer. Metabolism of irinotecan involves incorporation of ß-glucuronic acid to facilitate excretion. During transit of the glucuronidated product through the gastrointestinal tract, an induced upregulation of gut microbial ß-glucuronidase (GUS) activity may cause severe diarrhea and thus force many patients to stop treatment. We herein report the development of uronic isofagomine (UIFG) derivatives that act as general, potent inhibitors of bacterial GUSs, especially those of Escherichia coli and Clostridium perfringens. The best inhibitor, C6-nonyl UIFG, is 23,300-fold more selective for E. coli GUS than for human GUS (Ki = 0.0045 and 105 µM, respectively). Structural evidence indicated that the loss of coordinated water molecules, with the consequent increase in entropy, contributes to the high affinity and selectivity for bacterial GUSs. The inhibitors also effectively reduced irinotecan-induced diarrhea in mice without damaging intestinal epithelial cells.


Assuntos
Bactérias/efeitos dos fármacos , Colo/microbiologia , Diarreia/prevenção & controle , Inibidores Enzimáticos/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Glucuronidase/antagonistas & inibidores , Imino Piranoses/farmacologia , Irinotecano , Ácidos Urônicos/farmacologia , Animais , Bactérias/enzimologia , Linhagem Celular , Diarreia/induzido quimicamente , Diarreia/microbiologia , Modelos Animais de Doenças , Feminino , Glucuronidase/metabolismo , Humanos , Camundongos Endogâmicos BALB C
4.
N Biotechnol ; 63: 19-28, 2021 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-33640482

RESUMO

The synthesis of aldol adduct (3S,4R)-6-[(benzyloxycarbonyl)amino]-5,6-dideoxyhex-2-ulose, a precursor of the interesting dietary supplement, iminosugar d-fagomine, was studied in a cascade reaction with three enzymes starting from Cbz-N-3-aminopropanol. This system was studied previously using a statistical optimization method which enabled a 79 % yield of the aldol adduct with a 10 % yield of the undesired amino acid by-product. Here, a kinetic model of the cascade, including enzyme operational stability decay rate and the undesired overoxidation of the intermediate product, was developed. The validated model was instrumental in the optimization of the cascade reaction in the batch reactor. Simulations were carried out to determine the variables with the most significant impact on substrate conversion and product yield. As a result, process conditions were found that provided the aldol adduct in 92 % yield with only 0.7 % yield of the amino acid in a one-pot one-step reaction. Additionally, compared to previous work, this improved process outcome was achieved at lower concentrations of two enzymes used in the reaction. With this study the advantages are demonstrated of a modelling approach in developing complex biocatalytical processes. Mathematical models enable better understanding of the interactions of variables in the investigated system, reduce cost, experimental efforts in the lab and time necessary to obtain results since the simulations are carried out in silico.


Assuntos
Álcool Desidrogenase/metabolismo , Frutose-Bifosfato Aldolase/metabolismo , Imino Piranoses/metabolismo , Complexos Multienzimáticos/metabolismo , NADH NADPH Oxirredutases/metabolismo , Biocatálise , Imino Piranoses/química , Cinética , Estrutura Molecular
5.
Yakugaku Zasshi ; 141(1): 15-24, 2021.
Artigo em Japonês | MEDLINE | ID: mdl-33390442

RESUMO

Iminosugars are one of the compounds that mimic the structure of monosaccharides. Such sugar mimics have the ability to effectively and specifically inhibit various glycosidases and glycosyltransferases. After studying iminopyranose, miglitol, which has α-glucosidase inhibitory activity, was approved and used in the clinical treatment of diabetes. This study focused on l-iminofuranose derivatives to develop new anti-diabetic drug. As a result, it was found that l-iminofuranose having an alkyl group at C1 position show potent α-glucosidase inhibitory activity. Further structural-activity relationship studies were conducted, and interesting findings were obtained. This paper describes the details of those research developments.


Assuntos
1-Desoxinojirimicina/análogos & derivados , Diabetes Mellitus/tratamento farmacológico , Inibidores de Glicosídeo Hidrolases , Hipoglicemiantes , Imino Piranoses/síntese química , Imino Piranoses/farmacologia , 1-Desoxinojirimicina/síntese química , 1-Desoxinojirimicina/química , 1-Desoxinojirimicina/farmacologia , 1-Desoxinojirimicina/uso terapêutico , Animais , Humanos , Imino Piranoses/química , Imino Piranoses/uso terapêutico , Relação Estrutura-Atividade , alfa-Glucosidases
6.
Protein Expr Purif ; 177: 105752, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32949707

RESUMO

Alpha galactosidase (a-Gal) is an acidic hydrolase that plays a critical role in hydrolyzing the terminal alpha-galactoyl moiety from glycolipids and glycoproteins. There are over a hundred mutations reported for the GLA gene that encodes a-Gal that result in reduced protein synthesis, protein instability, and reduction in function. The deficiencies of a-Gal can cause Fabry disease, a rare lysosomal storage disorder (LSD) caused by the failure to catabolize alpha-d-galactoyl glycolipid moieties. The current standard of care for Fabry disease is enzyme replacement therapy (ERT) where the purified recombinant form of human a-Gal is given to patients. The manufacture of a-Gal is currently performed utilizing traditional large-scale chromatography processes. Developing an affinity resin for the purification of a-Gal would reduce the complexity of the manufacturing process, reduce costs, and potentially produce a higher quality a-Gal. After the evaluation of many small molecules, a commercially available small molecule biomimetic, N-5-Carboxypentyl-1-deoxygalactonojirimycin (N5C-DGJ), was utilized for the development of a novel small molecule biomimetic affinity resin for a-Gal. Affinity purified a-Gal demonstrated a purity greater than 90%, exhibited expected thermal stability and specific activity. Complementing this affinity purification is the development of an elution buffer system that confers an increased thermal stability to a-Gal. The N5C-DGJ affinity resin tolerated sodium hydroxide sanitization with no loss of binding capacity, making it amenable to large scale purification processes and potential use in manufacturing. This novel method for purifying the challenging a-Gal enzyme can be extended to other enzyme replacement therapies.


Assuntos
Cromatografia de Afinidade/métodos , Clonagem Molecular/métodos , Galactose/química , Imino Piranoses/química , Animais , Células CHO , Cricetulus , Estabilidade Enzimática , Expressão Gênica , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Humanos , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , alfa-Galactosidase/genética , alfa-Galactosidase/metabolismo
8.
Molecules ; 25(17)2020 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-32899288

RESUMO

Glycosidase inhibitors have shown great potential as pharmacological chaperones for lysosomal storage diseases. In light of this, a series of new cyclopentanoid ß-galactosidase inhibitors were prepared and their inhibitory and pharmacological chaperoning activities determined and compared with those of lipophilic analogs of the potent ß-d-galactosidase inhibitor 4-epi-isofagomine. Structure-activity relationships were investigated by X-ray crystallography as well as by alterations in the cyclopentane moiety such as deoxygenation and replacement by fluorine of a "strategic" hydroxyl group. New compounds have revealed highly promising activities with a range of ß-galactosidase-compromised human cell lines and may serve as leads towards new pharmacological chaperones for GM1-gangliosidosis and Morquio B disease.


Assuntos
Ciclopentanos/farmacologia , Galactosidases/metabolismo , Imino Piranoses/farmacologia , Lisossomos/enzimologia , Chaperonas Moleculares/metabolismo , Cristalização , Ciclopentanos/síntese química , Ciclopentanos/química , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Galactosidases/antagonistas & inibidores , Humanos , Imino Piranoses/síntese química , Imino Piranoses/química , Ligantes , Lisossomos/efeitos dos fármacos , Conformação Molecular , Proteínas Mutantes/metabolismo
9.
J Card Surg ; 35(8): 2047-2049, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32652625

RESUMO

Mediastinal paragangliomas are very uncommon neuroendocrine neoplasms. Due to their tissue of origin (sympathetic ganglia of the great vessels), they tend to arise deep within pericardial space and, more importantly, intimately attached to great vessels, which makes surgical resection, even with cardiopulmonary bypass, very challenging. This commentary accompanies the case report describing complex surgical management of a paraganglioma located in the anterior mediastinum that was initially thought to be a thymoma.


Assuntos
Neoplasias do Mediastino/cirurgia , Paraganglioma/cirurgia , Procedimentos Cirúrgicos Torácicos/métodos , Ponte Cardiopulmonar , Diagnóstico Diferencial , Diagnóstico por Imagem , Galactosamina/análogos & derivados , Humanos , Imino Piranoses , Neoplasias do Mediastino/diagnóstico , Mediastino/cirurgia , Paraganglioma/diagnóstico , Timoma , Neoplasias do Timo
10.
Int J Mol Sci ; 21(9)2020 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-32397443

RESUMO

Iminosugars are sugar analogues endowed with a high pharmacological potential. The wide range of biological activities exhibited by these glycomimetics associated with their excellent drug profile make them attractive therapeutic candidates for several medical interventions. The ability of iminosugars to act as inhibitors or enhancers of carbohydrate-processing enzymes suggests their potential use as therapeutics for the treatment of cystic fibrosis (CF). Herein we review the most relevant advances in the field, paying attention to both the chemical synthesis of the iminosugars and their biological evaluations, resulting from in vitro and in vivo assays. Starting from the example of the marketed drug NBDNJ (N-butyl deoxynojirimycin), a variety of iminosugars have exhibited the capacity to rescue the trafficking of F508del-CFTR (deletion of F508 residue in the CF transmembrane conductance regulator), either alone or in combination with other correctors. Interesting results have also been obtained when iminosugars were considered as anti-inflammatory agents in CF lung disease. The data herein reported demonstrate that iminosugars hold considerable potential to be applied for both therapeutic purposes.


Assuntos
Fibrose Cística/tratamento farmacológico , Compostos Heterocíclicos com 1 Anel/uso terapêutico , 1-Desoxinojirimicina/análogos & derivados , 1-Desoxinojirimicina/química , 1-Desoxinojirimicina/uso terapêutico , Anti-Inflamatórios/química , Anti-Inflamatórios/uso terapêutico , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Glicosídeo Hidrolases/antagonistas & inibidores , Glicosiltransferases/antagonistas & inibidores , Compostos Heterocíclicos com 1 Anel/síntese química , Compostos Heterocíclicos com 1 Anel/química , Humanos , Imino Piranoses/química , Imino Piranoses/uso terapêutico , Inflamação , Estrutura Molecular , Mutação , Deleção de Sequência , Tartaratos/química , Tartaratos/uso terapêutico
11.
Angew Chem Int Ed Engl ; 59(26): 10466-10469, 2020 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-32191378

RESUMO

Gaucher disease is caused by mutations in human acid ß-glucosidase or glucocerebrosidase (GCase), the enzyme responsible for hydrolysis of glucosyl ceramide in the lysosomes. Imino- and azasugars such as 1-deoxynojirimycin and isofagomine are strong inhibitors of the enzyme and are of interest in pharmacological chaperone therapy of the disease. Despite several crystal structures of the enzyme with the imino- and azasugars bound in the active site having been resolved, the actual acid-base chemistry of the binding is not known. In this study we show, using photoinduced electron transfer (PET), that 1-deoxynojirimycin and isofagomine derivatives are protonated by human acid ß-glucosidase when bound, even if they are completely unprotonated outside the enzyme. While isofagomine derivative protonation to some degree was foreshadowed by earlier crystal structures, 1-deoxynojirimycin derivatives were not believed to act as basic amines in the enzyme.


Assuntos
1-Desoxinojirimicina/análogos & derivados , Inibidores Enzimáticos/química , Glucosilceramidase/química , Imino Piranoses/química , Prótons , Ensaios Enzimáticos , Corantes Fluorescentes/química , Glucosilceramidase/antagonistas & inibidores , Humanos , Fenantrenos/química
12.
Yakugaku Zasshi ; 140(3): 443-448, 2020.
Artigo em Japonês | MEDLINE | ID: mdl-32115567

RESUMO

The consumption of health food products, such as Foods with Function Claims, has grown in Japan. Significant information, such as possible side effects or drug interactions, are expected to be described on the packaging to help consumers to make an informed choice about products. In this study, we checked the items described on the packaging of Foods with Function Claims containing eicosapentaenoic acid (EPA) and/or docosahexaenoic acid (DHA), Salacinol/Fagomine/Neokotalanol, or Varyl-Tyrosine/Lactotripeptide. We found that the label information on the package have issues that need to be addressed; for example, the description about a warning for concomitant use with antithrombotic drugs was found in only 29.7% of EPA and/or DHA containing products (44 out of 148). Providing information for safe usage of products to consumers is pivotal. Therefore, improving product labeling, and further pharmaceutical support in case of taking health foods, should be considered.


Assuntos
Rotulagem de Alimentos , Alimento Funcional , Ácidos Docosa-Hexaenoicos/análise , Ácido Eicosapentaenoico/análise , Análise de Alimentos , Imino Piranoses/análise , Álcoois Açúcares/análise , Sulfatos/análise , Inquéritos e Questionários , Tioaçúcares/análise
13.
J Exp Bot ; 71(9): 2585-2595, 2020 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-31960023

RESUMO

The double-flower phenotype has been selected by humans for its attractiveness in various plant species and it is of great commercial value for the ornamental market. In this study we investigated the genetic determinant of the dominant double-flower trait in carnation, petunia, and Rosa rugosa, and identified mutant alleles of TARGET OF EAT (TOE)-type genes characterized by a disruption of the miR172 target sequence and of the C-terminal portion of the encoded protein. Despite the phylogenetic distance between these eudicots, which diverged in the early Cretaceous, the orthologous genes carrying these mutations all belong to a single TOE-type subgroup, which we name as PETALOSA (PET). Homology searches allowed us to identify PET sequences in various other species. To confirm the results from naturally occurring mutations, we used CrispR-Cas9 to induce lesions within the miR172 target site of Nicotiana tabacum PET genes, and this resulted in the development of supernumerary petaloid structures. This study describes pet alleles in economically important ornamental species and provides evidence about the possibility of identifying and engineering PET genes to obtain the desirable double-flower trait in different plants.


Assuntos
Dianthus/genética , Flores , Regulação da Expressão Gênica de Plantas , Petunia/genética , Rosa/genética , Flores/genética , Imino Piranoses , Mutação , Fenótipo , Filogenia
14.
Mol Nutr Food Res ; 64(1): e1900564, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31657510

RESUMO

SCOPE: This study examines the long-term functional effects of d-fagomine on sucrose-induced factors of metabolic dysfunctions and explores possible molecular mechanisms behind its action. METHODS AND RESULTS: Wistar Kyoto rats are fed a 35% sucrose solution with d-fagomine (or not, for comparison) or mineral water (controls) for 24 weeks. The following are recorded: body weight; energy intake; glucose tolerance; plasma leptin concentration and lipid profile; populations of Bacteroidetes, Firmicutes, bacteroidales, clostridiales, enterobacteriales, and Escherichia coli in feces; blood pressure; urine uric acid and F2t isoprostanes (F2 -IsoPs); perigonadal fat deposition; and hepatic histology and diacylglycerols (DAGs) in liver and adipose tissue. d-Fagomine reduces sucrose-induced hypertension, urine uric acid and F2 -IsoPs (markers of oxidative stress), steatosis, and liver DAGs, without significantly affecting perigonadal fat deposition, and impaired glucose tolerance. It also promotes excretion of enterobacteriales generated by the dietary intervention. CONCLUSION: d-fagomine counteracts sucrose-induced steatosis and hypertension, presumably by reducing the postprandial levels of fructose in the liver.


Assuntos
Fagopyrum/química , Hipertensão/tratamento farmacológico , Imino Piranoses/farmacologia , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/metabolismo , Animais , Diglicerídeos/metabolismo , Ingestão de Energia/efeitos dos fármacos , Microbioma Gastrointestinal/efeitos dos fármacos , Hipertensão/induzido quimicamente , Isoprostanos/urina , Leptina/sangue , Lipídeos/sangue , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Masculino , Hepatopatia Gordurosa não Alcoólica/induzido quimicamente , Período Pós-Prandial , Ratos Endogâmicos WKY , Sacarose/toxicidade , Ácido Úrico/sangue , Ácido Úrico/urina
15.
Sci Rep ; 9(1): 16628, 2019 11 12.
Artigo em Inglês | MEDLINE | ID: mdl-31719544

RESUMO

Food contains bioactive compounds that may prevent changes in gut microbiota associated with Westernized diets. The aim of this study is to explore the possible additive effects of D-fagomine and ω-3 PUFAs (EPA/DHA 1:1) on gut microbiota and related risk factors during early stages in the development of fat-induced pre-diabetes. Male Sprague Dawley (SD) rats were fed a standard diet, or a high-fat (HF) diet supplemented with D-fagomine, EPA/DHA 1:1, a combination of both, or neither, for 24 weeks. The variables measured were fasting glucose and glucose tolerance, plasma insulin, liver inflammation, fecal/cecal gut bacterial subgroups and short-chain fatty acids (SCFAs). The animals supplemented with D-fagomine alone and in combination with ω-3 PUFAs accumulated less fat than those in the non-supplemented HF group and those given only ω-3 PUFAs. The combined supplements attenuated the high-fat-induced incipient insulin resistance (IR), and liver inflammation, while increasing the cecal content, the Bacteroidetes:Firmicutes ratio and the populations of Bifidobacteriales. The functional effects of the combination of D-fagomine and EPA/DHA 1:1 against gut dysbiosis and the very early metabolic alterations induced by a high-fat diet are mainly those of D-fagomine complemented by the anti-inflammatory action of ω-3 PUFAs.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Ácidos Graxos Ômega-3/uso terapêutico , Microbioma Gastrointestinal/efeitos dos fármacos , Imino Piranoses/uso terapêutico , Estado Pré-Diabético/etiologia , Animais , Glicemia/análise , Quimioterapia Combinada , Ácidos Graxos Ômega-3/administração & dosagem , Teste de Tolerância a Glucose , Imino Piranoses/administração & dosagem , Insulina/sangue , Leptina/sangue , Masculino , Estado Pré-Diabético/microbiologia , Estado Pré-Diabético/prevenção & controle , Ratos , Ratos Sprague-Dawley , Fatores de Risco
16.
Nutrients ; 11(11)2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31683529

RESUMO

Some functional food components may help maintain homeostasis by promoting balanced gut microbiota. Here, we explore the possible complementary effects of d-fagomine and ω-3 polyunsaturated fatty acids (ω-3 PUFAs) eicosapentaenoic acid/docosahexaenoic acid (EPA/DHA 1:1) on putatively beneficial gut bacterial strains. Male Sprague-Dawley rats were supplemented with d-fagomine, ω-3 PUFAs, or both, for 23 weeks. Bacterial subgroups were evaluated in fecal DNA by quantitative real-time polymerase chain reaction (qRT-PCR) and short-chain fatty acids were determined by gas chromatography. We found that the populations of the genus Prevotella remained stable over time in animals supplemented with d-fagomine, independently of ω-3 PUFA supplementation. Animals in these groups gained less weight than controls and rats given only ω-3 PUFAs. d-Fagomine supplementation together with ω-3 PUFAs maintained the relative populations of Bacteroides. ω-3 PUFAs alone or combined with d-fagomine reduced the amount of acetic acid and total short-chain fatty acids in feces. The plasma levels of pro-inflammatory arachidonic acid derived metabolites, triglycerides and cholesterol were lower in both groups supplemented with ω-3 PUFAs. The d-fagomine and ω-3 PUFAs combination provided the functional benefits of each supplement. Notably, it helped stabilize populations of Prevotella in the rat intestinal tract while reducing weight gain and providing the anti-inflammatory and cardiovascular benefits of ω-3 PUFAs.


Assuntos
Peso Corporal/efeitos dos fármacos , Ácidos Graxos Ômega-3/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Imino Piranoses/farmacologia , Administração Oral , Animais , Bacteroides/efeitos dos fármacos , Suplementos Nutricionais , Fagopyrum/química , Ácidos Graxos Ômega-3/administração & dosagem , Imino Piranoses/administração & dosagem , Masculino , Prevotella/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Alimentos Marinhos
17.
J Med Chem ; 62(12): 5832-5843, 2019 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-31017416

RESUMO

α-Mannosidosis (AM) results from deficient lysosomal α-mannosidase (LAMAN) activity and subsequent substrate accumulation in the lysosome, leading to severe pathology. Many of the AM-causative mutations compromise enzyme folding and could be rescued with purpose-designed pharmacological chaperones (PCs). We found that PCs combining a LAMAN glycone-binding motif based on the 5 N,6 O-oxomethylidenemannojirimycin (OMJ) glycomimetic core and different aglycones, in either mono- or multivalent displays, elicit binding modes involving glycone and nonglycone enzyme regions that reinforce the protein folding and stabilization potential. Multivalent derivatives exhibited potent enzyme inhibition that generally prevailed over the chaperone effect. On the contrary, monovalent OMJ derivatives with LAMAN aglycone binding area-fitting substituents proved effective as activity enhancers for several mutant LAMAN forms in AM patient fibroblasts and/or transfected MAN2 B1-KO cells. This translated into a significant improvement in endosomal/lysosomal function, reverting not only the primary LAMAN substrate accumulation but also the additional downstream consequences such as cholesterol accumulation.


Assuntos
Desenho de Fármacos , Imino Piranoses/química , Imino Piranoses/farmacologia , alfa-Manosidose/tratamento farmacológico , Motivos de Aminoácidos , Linhagem Celular , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Glicosídeos/química , Humanos , Imino Piranoses/uso terapêutico , alfa-Manosidase/química , alfa-Manosidase/metabolismo , alfa-Manosidose/metabolismo
18.
Molecules ; 24(2)2019 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-30669468

RESUMO

A series of simple C-alkyl pyrrolidines already known as cytotoxic inhibitors of ceramide glucosylation in melanoma cells can be converted into their corresponding 6-membered analogues by means of a simple ring expansion. This study illustrated how an isomerisation from iminosugar pyrrolidine toward piperidine could invert their targeting from glucosylceramide (GlcCer) formation toward GlcCer hydrolysis. Thus, we found that the 5-membered ring derivatives did not inhibit the hydrolysis reaction of GlcCer catalysed by lysosomal ß-glucocerebrosidase (GBA). On the other hand, the ring-expanded C-alkyl piperidine isomers, non-cytotoxic and inactive regarding ceramide glucosylation, revealed to be potent inhibitors of GBA. A molecular docking study showed that the positions of the piperidine ring of the compound 6b and its analogous 2-O-heptyl DIX 8 were similar to that of isofagomine. Furthermore, compound 6b promoted mutant GBA enhancements over 3-fold equivalent to that of the related O-Hept DIX 8 belonging to one of the most potent iminosugar-based pharmacological chaperone series reported to date.


Assuntos
Ceramidas/química , Inibidores Enzimáticos/química , Glucosilceramidase/antagonistas & inibidores , Imino Açúcares/química , Animais , Células Cultivadas , Fibroblastos/efeitos dos fármacos , Glucosilceramidase/metabolismo , Humanos , Hidrólise , Imino Piranoses/química , Isomerismo , Lisossomos , Melanoma Experimental , Camundongos , Simulação de Acoplamento Molecular , Estrutura Molecular , Piperidinas/química , Ligação Proteica , Pirrolidinas/química , Relação Estrutura-Atividade
19.
Nat Prod Res ; 33(8): 1182-1190, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29862842

RESUMO

Metabolism, transformation and dynamic changes of DNJ, 2-O-α-D-Gal-DNJ, fagomine, isofagomine and 4-O-ß-d-Glc-fagomine from mulberry leaves in silkworms at different instars were observed. UPLC-Q/TOF-MS and UPLC-TQ/MS methods were adopted for qualitative and quantitative analysis respectively. Three species mulberry leaves were used to feed the silkworm as controls. By analyzing and comparing the content changes of DNJ, fagomine and their derivatives in silkworms and silkworm excrement at different instar, we revealed the dynamic changes, confirmed the enrichment effect of the polyhydroxy alkaloids by silkworm, and inferred the conversion process behind this effect. The experimental results indicated that DNJ and its derivatives turned into some intermediate substances in the metabolic process, and finally they converted back and the content increased. Fagomine and its derivatives interconverted into each other in the process, 4-O-ß-d-Glc-fagomine transformed into fagomine, while fagomine transformed into isofagomine.


Assuntos
Alcaloides/metabolismo , Ração Animal/análise , Bombyx/metabolismo , Morus/metabolismo , Animais , Biotransformação , Bombyx/química , Bombyx/fisiologia , Cromatografia Líquida de Alta Pressão , Imino Piranoses/análise , Imino Piranoses/metabolismo , Espectrometria de Massas , Folhas de Planta/metabolismo
20.
Bioorg Med Chem ; 26(20): 5462-5469, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30270003

RESUMO

(5aR)-5a-C-pentyl-4-epi-isofagomine 1 is a powerful inhibitor of lysosomal ß-galactosidase and a remarkable chaperone for mutations associated with GM1-gangliosidosis and Morquio disease type B. We report herein an improved synthesis of this compound and analogs (5a-C-methyl, pentyl, nonyl and phenylethyl derivatives), and a crystal structure of a synthetic intermediate that confirms its configuration resulting from the addition of a Grignard reagent. These compounds were evaluated as glycosidase inhibitors and their potential as chaperones for mutant lysosomal galactosidases determined. Based on these results and on docking studies, the 5-C-pentyl derivative 1 was selected as the optimal structure for further investigations: this compound induces the maturation of mutated ß-galactosidase in fibroblasts of a GM1-gangliosidosis patient and promote the decrease of keratan sulfate and oligosaccharide load in patient cells. Compound 1 is clearly capable of restoring ß-galactosidase activity and of promoting maturation of the protein, which should result in significant clinical benefit. These properties strongly support the development of compound 1 for the treatment of GM1-gangliosidosis and Morquio disease type B patients harboring ß-galactosidase mutations sensitive to pharmacological chaperoning.


Assuntos
Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Gangliosidose GM1/tratamento farmacológico , Imino Piranoses/química , Imino Piranoses/farmacologia , Mucopolissacaridose IV/tratamento farmacológico , beta-Galactosidase/antagonistas & inibidores , Descoberta de Drogas , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/uso terapêutico , Gangliosidose GM1/enzimologia , Gangliosidose GM1/genética , Gangliosidose GM1/metabolismo , Humanos , Imino Piranoses/síntese química , Imino Piranoses/uso terapêutico , Simulação de Acoplamento Molecular , Mucopolissacaridose IV/enzimologia , Mucopolissacaridose IV/genética , Mucopolissacaridose IV/metabolismo , Mutação/efeitos dos fármacos , Relação Estrutura-Atividade , beta-Galactosidase/genética , beta-Galactosidase/metabolismo
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