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1.
Biochem J ; 480(8): 495-520, 2023 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-37022297

RESUMO

Isoprenoids, including dolichols (Dols) and polyprenols (Prens), are ubiquitous components of eukaryotic cells. In plant cells, there are two pathways that produce precursors utilized for isoprenoid biosynthesis: the mevalonate (MVA) pathway and the methylerythritol phosphate (MEP) pathway. In this work, the contribution of these two pathways to the biosynthesis of Prens and Dols was addressed using an in planta experimental model. Treatment of plants with pathway-specific inhibitors and analysis of the effects of various light conditions indicated distinct biosynthetic origin of Prens and Dols. Feeding with deuteriated, pathway-specific precursors revealed that Dols, present in leaves and roots, were derived from both MEP and MVA pathways and their relative contributions were modulated in response to precursor availability. In contrast, Prens, present in leaves, were almost exclusively synthesized via the MEP pathway. Furthermore, results obtained using a newly introduced here 'competitive' labeling method, designed so as to neutralize the imbalance of metabolic flow resulting from feeding with a single pathway-specific precursor, suggest that under these experimental conditions one fraction of Prens and Dols is synthesized solely from endogenous precursors (deoxyxylulose or mevalonate), while the other fraction is synthesized concomitantly from endogenous and exogenous precursors. Additionally, this report describes a novel methodology for quantitative separation of 2H and 13C distributions observed for isotopologues of metabolically labeled isoprenoids. Collectively, these in planta results show that Dol biosynthesis, which uses both pathways, is significantly modulated depending on pathway productivity, while Prens are consistently derived from the MEP pathway.


Assuntos
Arabidopsis , Dolicóis , Dolicóis/metabolismo , Poliprenois/metabolismo , Ácido Mevalônico/metabolismo , Arabidopsis/metabolismo , Fosfatos/metabolismo , Terpenos/metabolismo
2.
J Med Virol ; 95(11): e29271, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-38009626

RESUMO

The introduction of primary human papillomavirus (HPV) cervical cancer screening requires the implementation of an appropriate triage strategy that will be effective in detecting high-grade cervical disease without losing diagnostic specificity. From the 30.066 screening tests results, a total of 1086 with available high-risk human papillomavirus (HRHPV) with limited genotyping, cytology, and p16/Ki67 dual-stain were selected. Two triage strategies for primary HPV screening were analyzed retrospectively based on the study group. Performance characteristics for p16/Ki67 and cytology triage in the detection of cervical intraepithelial neoplasia grade 2 or worse (CIN2+) and grade 3 or worse (CIN3+) were calculated, detected in colposcopic biopsy. In HPV16/18-positive cases, primary HPV with p16/Ki67 triage was significantly more specific than cytology (53.1%/16.8% for CIN2+; p < 0.0001; 45.9%/17.0% for CIN3+; p < 0.0001), with yielded sensitivity (95.7%/84.8% for CIN2+; p = 0.0955; 100.0%/87.5% for CIN3+; p = 0.0832). In other HRHPV-positive cases (N16/N18), p16/Ki67 triage was also significantly higher specific (51.3%/15.3% for CIN2+; p < 0.0001; 44.5%/16.5% for CIN3+; p < 0.0001), with sensitivity (92.3%/74.4% for CIN2+; p = 0.0522; 90.9%/81.8% for CIN3+; p = 0.5637). Diagnostic predictive values were significantly higher for p16/Ki67 triage with the highest PPV in HPV16/18-positive cases for CIN2+ (45.4%; 95% confidence interval [CI]: 35.2-55.8; p < 0.0001) and very high NPV in all HPV-positive cases regardless of detected genotype (96.3%-100.0%). The risk (1-NPV) for CIN3+ in HRHPV16/18-positive/p16/Ki67-negative women was 0.0%. Superior diagnostic performance compared to cytology for detecting cervical cancer precursors indicates that p16/Ki67 dual-immunostain may be a highly effective tool of triage in primary HPV screening with limited HPV 16/18 genotyping in secondary cervical cancer prevention.


Assuntos
Infecções por Papillomavirus , Displasia do Colo do Útero , Neoplasias do Colo do Útero , Feminino , Humanos , Antígeno Ki-67/genética , Papillomavirus Humano 16/genética , Papillomavirus Humano , Genótipo , Detecção Precoce de Câncer/métodos , Estudos Retrospectivos , Triagem/métodos , Papillomavirus Humano 18/genética , Inibidor p16 de Quinase Dependente de Ciclina/genética
3.
Plant Cell ; 29(7): 1709-1725, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28655749

RESUMO

Plants accumulate a family of hydrophobic polymers known as polyprenols, yet how they are synthesized, where they reside in the cell, and what role they serve is largely unknown. Using Arabidopsis thaliana as a model, we present evidence for the involvement of a plastidial cis-prenyltransferase (AtCPT7) in polyprenol synthesis. Gene inactivation and RNAi-mediated knockdown of AtCPT7 eliminated leaf polyprenols, while its overexpression increased their content. Complementation tests in the polyprenol-deficient yeast ∆rer2 mutant and enzyme assays with recombinant AtCPT7 confirmed that the enzyme synthesizes polyprenols of ∼55 carbons in length using geranylgeranyl diphosphate (GGPP) and isopentenyl diphosphate as substrates. Immunodetection and in vivo localization of AtCPT7 fluorescent protein fusions showed that AtCPT7 resides in the stroma of mesophyll chloroplasts. The enzymatic products of AtCPT7 accumulate in thylakoid membranes, and in their absence, thylakoids adopt an increasingly "fluid membrane" state. Chlorophyll fluorescence measurements from the leaves of polyprenol-deficient plants revealed impaired photosystem II operating efficiency, and their thylakoids exhibited a decreased rate of electron transport. These results establish that (1) plastidial AtCPT7 extends the length of GGPP to ∼55 carbons, which then accumulate in thylakoid membranes; and (2) these polyprenols influence photosynthetic performance through their modulation of thylakoid membrane dynamics.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/fisiologia , Fotossíntese/fisiologia , Plastídeos/metabolismo , Transferases/metabolismo , Proteínas de Arabidopsis/genética , Dimetilaliltranstransferase/genética , Dimetilaliltranstransferase/metabolismo , Teste de Complementação Genética , Folhas de Planta/genética , Folhas de Planta/metabolismo , Plantas Geneticamente Modificadas , Fosfatos de Poli-Isoprenil/metabolismo , Interferência de RNA , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Especificidade por Substrato , Tilacoides/metabolismo , Transferases/genética
4.
Int J Mol Sci ; 21(4)2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-32093271

RESUMO

Clinical phenotypes of familial hypobetalipoproteinemia (FHBL) are related to a number of defective apolipoprotein B (APOB) alleles. Fatty liver disease is a typical manifestation, but serious neurological symptoms can appear. In this study, genetic analysis of the APOB gene and ophthalmological diagnostics were performed for family members with FHBL. Five relatives with FHBL, including a proband who developed neurological disorders, were examined. A sequencing analysis of the whole coding region of the APOB gene, including flanking intronic regions, was performed using the next-generation sequencing (NGS) method. Electrophysiological ophthalmological examinations were also done. In the proband and his affected relatives, NGS identified the presence of the pathogenic, rare heterozygous splicing variant c.3696+1G>T. Two known heterozygous missense variants-c.2188G>A, p.(Val730Ile) and c.8353A>C, p.(Asn2785His)-in the APOB gene were also detected. In all patients, many ophthalmologic abnormalities in electrophysiological tests were also found. The identified splicing variant c.3696+1G>T can be associated with observed autosomal, dominant FHBL with coexisting neurological symptoms, and both identified missense variants could be excluded as the main cause of observed clinical signs, according to mutation databases and the literature. Electroretinography examination is a sensitive method for the detection of early neuropathy and should therefore be recommended for the care of patients with FHBL.


Assuntos
Apolipoproteína B-100 , Hipobetalipoproteinemia Familiar por Apolipoproteína B , Mutação de Sentido Incorreto , Doenças do Sistema Nervoso , Splicing de RNA , Adulto , Idoso , Substituição de Aminoácidos , Apolipoproteína B-100/genética , Apolipoproteína B-100/metabolismo , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Hipobetalipoproteinemia Familiar por Apolipoproteína B/diagnóstico por imagem , Hipobetalipoproteinemia Familiar por Apolipoproteína B/genética , Hipobetalipoproteinemia Familiar por Apolipoproteína B/metabolismo , Masculino , Doenças do Sistema Nervoso/diagnóstico por imagem , Doenças do Sistema Nervoso/genética , Doenças do Sistema Nervoso/metabolismo
5.
Plant Physiol ; 174(2): 857-874, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28385729

RESUMO

The cooperation of the mevalonate (MVA) and methylerythritol phosphate (MEP) pathways, operating in parallel in plants to generate isoprenoid precursors, has been studied extensively. Elucidation of the isoprenoid metabolic pathways is indispensable for the rational design of plant and microbial systems for the production of industrially valuable terpenoids. Here, we describe a new method, based on numerical modeling of mass spectra of metabolically labeled dolichols (Dols), designed to quantitatively follow the cooperation of MVA and MEP reprogrammed upon osmotic stress (sorbitol treatment) in Arabidopsis (Arabidopsis thaliana). The contribution of the MEP pathway increased significantly (reaching 100%) exclusively for the dominating Dols, while for long-chain Dols, the relative input of the MEP and MVA pathways remained unchanged, suggesting divergent sites of synthesis for dominating and long-chain Dols. The analysis of numerically modeled Dol mass spectra is a novel method to follow modulation of the concomitant activity of isoprenoid-generating pathways in plant cells; additionally, it suggests an exchange of isoprenoid intermediates between plastids and peroxisomes.


Assuntos
Arabidopsis/metabolismo , Dolicóis/química , Modelos Teóricos , Espectrometria de Massas por Ionização por Electrospray/métodos , Terpenos/metabolismo , Isótopos de Carbono , Cromatografia Gasosa/métodos , Dolicóis/metabolismo , Eritritol/análogos & derivados , Eritritol/metabolismo , Marcação por Isótopo/métodos , Redes e Vias Metabólicas , Ácido Mevalônico/análogos & derivados , Ácido Mevalônico/química , Ácido Mevalônico/metabolismo , Pressão Osmótica , Fitosteróis/biossíntese , Sorbitol/metabolismo , Fosfatos Açúcares/metabolismo , Xilulose/análogos & derivados , Xilulose/química
6.
Biochim Biophys Acta ; 1861(7): 617-29, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27094351

RESUMO

Apolipophorin III (apoLp-III), an insect homologue of human apolipoprotein E (apoE), is a widely used model protein in studies on protein-lipid interactions, and anti-Legionella activity of Galleria mellonella apoLp-III has been documented. Interestingly, exogenous choline-cultured Legionella dumoffii cells are considerably more susceptible to apoLp-III than non-supplemented bacteria. In order to explain these differences, we performed, for the first time, a detailed analysis of L. dumoffii lipids and a comparative lipidomic analysis of membranes of bacteria grown without and in the presence of exogenous choline. (31)P NMR analysis of L. dumoffii phospholipids (PLs) revealed a considerable increase in the phosphatidylcholine (PC) content in bacteria cultured on choline medium and a decrease in the phosphatidylethanolamine (PE) content in approximately the same range. The interactions of G. mellonella apoLp-III with lipid bilayer membranes prepared from PLs extracted from non- and choline-supplemented L. dumoffii cells were examined in detail by means of attenuated total reflection- and linear dichroism-Fourier transform infrared spectroscopy. Furthermore, the kinetics of apoLp-III binding to liposomes formed from L. dumoffii PLs was analysed by fluorescence correlation spectroscopy and fluorescence lifetime imaging microscopy using fluorescently labelled G. mellonella apoLp-III. Our results indicated enhanced binding of apoLp-III to and deeper penetration into lipid membranes formed from PLs extracted from the choline-supplemented bacteria, i.e. characterized by an increased PC/PE ratio. This could explain, at least in part, the higher susceptibility of choline-cultured L. dumoffii to G. mellonella apoLp-III.


Assuntos
Apolipoproteínas/química , Membrana Celular/química , Proteínas de Insetos/química , Legionella/química , Mariposas/microbiologia , Animais , Apolipoproteínas/isolamento & purificação , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Colina/farmacologia , Corantes Fluorescentes/química , Interações Hospedeiro-Patógeno , Humanos , Proteínas de Insetos/isolamento & purificação , Legionella/efeitos dos fármacos , Legionella/crescimento & desenvolvimento , Legionella/metabolismo , Bicamadas Lipídicas/química , Bicamadas Lipídicas/metabolismo , Lipossomos/química , Lipossomos/metabolismo , Mariposas/química , Fosfatidilcolinas/química , Fosfatidiletanolaminas/química , Ligação Proteica , Espectrometria de Fluorescência , Espectroscopia de Infravermelho com Transformada de Fourier
7.
Biochim Biophys Acta ; 1851(10): 1296-303, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26143379

RESUMO

Dolichols are, among others, obligatory cofactors of protein glycosylation in eukaryotic cells. It is well known that yeast cells accumulate a family of dolichols with Dol-15/16 dominating while upon certain physiological conditions a second family with Dol-21 dominating is noted. In this report we identified the presence of additional short-chain length polyprenols - all-trans Pren-7 in three yeast strains (SS328, BY4741 and L5366), Pren-7 was accompanied by traces of putative Pren-6 and -8. Moreover, in two of these strains a single polyprenol mainly-cis-Pren-11 was synthesized at the stationary phase of growth. Identity of polyprenols was confirmed by HR-HPLC/MS, NMR and metabolic labeling. Additionally, simvastatin inhibited their biosynthesis.


Assuntos
Saccharomyces cerevisiae/metabolismo , Terpenos/metabolismo , Saccharomyces cerevisiae/genética
8.
Biochim Biophys Acta ; 1841(2): 240-50, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24291644

RESUMO

cis-Prenyltransferases (CPTs) comprise numerous enzymes synthesizing isoprenoid hydrocarbon skeleton with isoprenoid units in the cis (Z) configuration. The chain-length specificity of a particular plant CPT is in most cases unknown despite thecomposition of the accumulated isoprenoids in the tissue of interest being well established. In this report AtCPT6, one of the nine Arabidopsis thaliana CPTs, is shown to catalyze the synthesis of a family of very short-chain polyisoprenoid alcohols of six, seven, and eight isoprenoid units, those of seven units dominating The product specificity of AtCPT6 was established in vivo following its expression in the heterologous system of the yeast Saccharomyces cerevisiae and was confirmed by the absence of specific products in AtCPT6 T-DNA insertion mutants and their overaccumulation in AtCPT6-overexpressing plants. These observations are additionally validated in silico using an AtCPT6 model obtained by homology modeling. AtCPT6 only partially complements the function of the yeast homologue of CPT-Rer2 since it restores the growth but not protein glycosylation in rer2delta yeast.This is the first in planta characterization of specific products of a plant CPT producing polyisoprenoids. Their distribution suggests that a joint activity of several CPTs is required to produce the complex mixture of polyisoprenoid alcohols found in Arabidopsis roots.


Assuntos
Arabidopsis/enzimologia , Terpenos/metabolismo , Transferases/fisiologia , Sequência de Aminoácidos , Modelos Moleculares , Dados de Sequência Molecular , Proteínas Recombinantes/biossíntese , Saccharomyces cerevisiae/genética , Transferases/química , Transferases/genética
9.
Biochim Biophys Acta ; 1841(7): 977-86, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24747199

RESUMO

2,3-Oxidosqualene is an intermediate in cholesterol biosynthesis and 2,3:22,23-dioxidosqualene act as the substrate for an alternative pathway that produces 24(S),25-epoxycholesterol which effects cholesterol homeostasis. In light of our previous findings concerning the biological effects of certain epoxidated all-trans-polyisoprenes, the effects of squalene carrying epoxy moieties on the second and third isoprene residues were investigated here. In cultures of HepG2 cells both monoepoxides of squalene and one of their hydrolytic products inhibited cholesterol synthesis and stimulated the synthesis of coenzyme Q (CoQ). Upon prolonged treatment the cholesterol content of these cells and its labeling with [(3)H]mevalonate were reduced, while the amount and labeling of CoQ increased. Injection of the squalene monoepoxides into mice once daily for 6days elevated the level of CoQ in their blood, but did not change the cholesterol level. The same effects were observed upon treatment of apoE-deficient mice and diabetic GK-rats. This treatment increased the hepatic level of CoQ10 in mice, but the amount of CoQ9, which is the major form, was unaffected. The presence of the active compounds in the blood was supported by the finding that cholesterol synthesis in the white blood cells was inhibited. Since the ratio of CoQ9/CoQ10 varies depending on the experimental conditions, the cells were titrated with substrate and inhibitors, leading to the conclusion that the intracellular isopentenyl-PP pool is a regulator of this ratio. Our present findings indicate that oxidosqualenes may be useful for stimulating both the synthesis and level of CoQ both in vitro and in vivo.


Assuntos
Colesterol/análogos & derivados , Colesterol/biossíntese , Hemiterpenos/metabolismo , Compostos Organofosforados/metabolismo , Esqualeno/análogos & derivados , Ubiquinona/análogos & derivados , Animais , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/patologia , Ácido Etidrônico/análogos & derivados , Ácido Etidrônico/farmacologia , Células Hep G2 , Humanos , Lovastatina/farmacologia , Masculino , Ácido Mevalônico/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Ratos , Ratos Wistar , Ácido Risedrônico , Esqualeno/metabolismo , Esqualeno/farmacologia , Ácidos Tricarboxílicos/farmacologia , Ubiquinona/biossíntese
10.
J Incl Phenom Macrocycl Chem ; 83(3-4): 321-334, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26549980

RESUMO

The article presents the synthesis of novel 13- and 16-membered azobenzocrown derivatives with peripheral thiol moieties and preliminary studies assessing their possible application in plasmonic sensors based on gold nanoparticles. The effect of the length of the chain connecting the macrocycle with the thiol group and the effect of the presence of the additional functional compound, i.e. lipoic acid, on the sensor response was analyzed. Colloidal gold nanoparticles modified with a 16-membered crown with a thiol group on oxyethylene (compound 12) or oxybutylene (compound 13) linker was found to have good properties, allowing for detection of potassium ions in aqueous solutions at concentrations 8-20 mM for bifunctionalized nanogold and 4-26 mM for less stable, colloidal gold modified only with thiol derivatives of azobenzocrowns. The response towards potassium cations of bifunctionalized nanogold modified with compound 13 was more stable in time than for the system incorporating compound 12. Compound 13, obtained with the highest yield among all presented thiol derivatives of azobenzocrowns, was selected for further, more detailed, studies.

11.
Biochim Biophys Acta ; 1831(2): 438-47, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23178167

RESUMO

Sugars are recognized as signaling molecules regulating the biosynthesis of secondary metabolites in plants. Here, a modulatory effect of sugars on dolichol and phytosterol profiles was noted in the hairy roots of Arabidopsis thaliana. Arabidopsis roots contain a complex dolichol mixture comprising three groups ('families') of dolichols differing in the chain-length. These dolichols, especially the longest ones are accompanied by considerable amounts of polyprenols of the same length. The spectrum of polyisoprenoid alcohols, i.e. dolichols and polyprenols, was dependent on sugar type (glucose or sucrose) and its concentration in the medium. Among the long-chain dolichols Dol/Pren-20 (dolichol or prenol molecule composed of 20 isoprene residues) and Dol/Pren-23 were the main components at 0.5% and 2% glucose, respectively. Moreover, the ratio of polyprenols versus respective dolichols was also modulated by sugar in this group of polyisoprenoids, with polyprenols dominating at 3% sucrose and dolichols at 2% glucose. Glucose concentration affected the expression level of genes encoding cis-prenyltransferases, enzymes responsible for elongation of the polyisoprenoid chain. The most abundant phytosterols of the A. thaliana roots, ß-sitosterol, stigmasterol and campesterol, were accompanied by corresponding stanols and traces of brassicasterol, stigmast-4,22-dien-3-one and stigmast-4-en-3-one. Similar to the polyisoprenoids, sterol profile responded to the sugar present in the medium, ß-sitosterol dominating in roots grown on 3% or lower glucose concentrations and stigmasterol in 3% sucrose. These results indicate an involvement of sugar signaling in the regulation of cis-prenyltransferases and phytosterol pathway enzymes.


Assuntos
Arabidopsis/metabolismo , Metabolismo dos Carboidratos , Fitosteróis/metabolismo , Terpenos/metabolismo , Disponibilidade Biológica , Raízes de Plantas/citologia , Raízes de Plantas/metabolismo
12.
Int J Mol Sci ; 15(5): 8256-79, 2014 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-24821544

RESUMO

Phosphatidycholine (PC) is the major membrane-forming phospholipid in eukaryotes but it has been found in only a limited number of prokaryotes. Bacteria synthesize PC via the phospholipid N-methylation pathway (Pmt) or via the phosphatidylcholine synthase pathway (Pcs) or both. Here, we demonstrated that Legionella dumoffii has the ability to utilize exogenous choline for phosphatidylcholine (PC) synthesis when bacteria grow in the presence of choline. The Pcs seems to be a primary pathway for synthesis of this phospholipid in L. dumoffii. Structurally different PC species were distributed in the outer and inner membranes. As shown by the LC/ESI-MS analyses, PC15:0/15:0, PC16:0/15:0, and PC17:0/17:1 were identified in the outer membrane and PC14:0/16:0, PC16:0/17:1, and PC20:0/15:0 in the inner membrane. L. dumoffii pcsA gene encoding phosphatidylcholine synthase revealed the highest sequence identity to pcsA of L. bozemanae (82%) and L. longbeachae (81%) and lower identity to pcsA of L. drancourtii (78%) and L. pneumophila (71%). The level of TNF-α in THP1-differentiated cells induced by live and temperature-killed L. dumoffii cultured on a medium supplemented with choline was assessed. Live L. dumoffii bacteria cultured on the choline-supplemented medium induced TNF-α three-fold less efficiently than cells grown on the non-supplemented medium. There is an evident effect of PC modification, which impairs the macrophage inflammatory response.


Assuntos
Colina/metabolismo , Legionella/enzimologia , Legionella/metabolismo , Vias Biossintéticas , Linhagem Celular , Genes Bacterianos , Humanos , Legionella/química , Legionella/genética , Macrófagos/microbiologia , Espectrometria de Massas , Fosfatidilcolinas/análise , Fosfatidilcolinas/metabolismo , Transferases (Outros Grupos de Fosfato Substituídos)/genética , Transferases (Outros Grupos de Fosfato Substituídos)/metabolismo
13.
Mol Cancer Ther ; 22(7): 807-817, 2023 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-36939275

RESUMO

Pharmacologic inhibition of the controlling immunity pathway enzymes arginases 1 and 2 (ARG1 and ARG2) is a promising strategy for cancer immunotherapy. Here, we report the discovery and development of OATD-02, an orally bioavailable, potent arginases inhibitor. The unique pharmacologic properties of OATD-02 are evidenced by targeting intracellular ARG1 and ARG2, as well as long drug-target residence time, moderate to high volume of distribution, and low clearance, which may jointly provide a weapon against arginase-related tumor immunosuppression and ARG2-dependent tumor cell growth. OATD-02 monotherapy had an antitumor effect in multiple tumor models and enhanced an efficacy of the other immunomodulators. Completed nonclinical studies and human pharmacokinetic predictions indicate a feasible therapeutic window and allow for proposing a dose range for the first-in-human clinical study in patients with cancer. SIGNIFICANCE: We have developed an orally available, small-molecule intracellular arginase 1 and 2 inhibitor as a potential enhancer in cancer immunotherapy. Because of its favorable pharmacologic properties shown in nonclinical studies, OATD-02 abolishes tumor immunosuppression induced by both arginases, making it a promising drug candidate entering clinical trials.


Assuntos
Arginase , Neoplasias , Humanos , Arginase/metabolismo , Neoplasias/tratamento farmacológico , Imunoterapia
14.
Rapid Commun Mass Spectrom ; 26(15): 1705-10, 2012 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-22730090

RESUMO

RATIONALE: The aim of this study was to determine whether Atmospheric Pressure Photoionization (APPI) was better suited for the mass spectrometric (MS) analysis of polyisoprenoid alcohols than the commonly used Electrospray Ionization (ESI) method. The APPI method should make possible the use of non-polar solvents without any of the additives required by ESI, together with improved detection limits. METHODS: The liquid chromatography (LC)/APPI-MS and LC/ESI-MS spectra of polyisoprenoid alcohol standards were acquired in both positive and negative ion mode, in methanol and hexane, using a triple quadrupole/linear ion trap tandem mass spectrometer equipped with both an ESI and an APPI ion source. RESULTS: In the positive ion mode peaks corresponding to [M + H - H(2)O](+) and [M + H](+) ions were observed in the APPI-MS spectra of polyprenols and dolichols, respectively. In the negative ion mode peaks corresponding to [M + O(2)](-•) and [M + Cl](-) ions were observed for both classes of polyisoprenoid alcohols. The detection limit of polyisoprenoid alcohols was established at the level of 10 pg. CONCLUSIONS: APPI turned out to be a method of choice for the identification and quantitation of polyisoprenoid alcohols by MS using both polar and non-polar solvents. APPI also enabled greater differentiation of polyprenols and dolichols occurring together in natural samples and gave much better TIC chromatograms without the need for the post-column salt addition required by ESI.


Assuntos
Cromatografia Líquida/métodos , Álcoois Graxos/química , Espectrometria de Massas/métodos , Álcoois Graxos/análise , Hexanos/química , Metanol/química
15.
Diagnostics (Basel) ; 11(11)2021 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-34829358

RESUMO

Recently, cervical cancer rates elevation has been noted in women aged 20-39 years in regions with a very high human development index (HDI). The onset of cancer elevation rates is observed in the age range of 25-29 years, which should necessitate effective precancer screening in younger age groups, including those <25 years. From 30.066 liquid-based screening tests results (n = 30.066), 3849 liquid-based cytology, 1321 high-risk human papillomavirus (HRHPV) and 316 p16/Ki67 performed in women <30 years were selected. Performance characteristics were calculated for three screening models: primary HRHPV with p16/Ki67 triage, primary cytology with reflex HPV and primary cytology alone. Primary HRHPV with p16/Ki67 triage was significantly more sensitive in high-grade squamous intraepithelial lesion quantified with cervical intraepithelial neoplasia grade 2 or worse [HSIL(CIN2+)] detection than cytology with reflex HRHPV and cytology alone (83.3% vs. 70.8%/45.8%) and had significantly higher diagnostic predictive values (PPV:29.4%/21.3%/22.9%; NPV:91.7%/82.9%/82.2%, respectively at CIN2+ threshold). The number of colposcopies per HSIL(CIN2+) detection indices was 3.4, 4.7 and 4.4, respectively. Primary HPV testing in women <30 years with p16/Ki67 triage of HPV-positive cases might be an effective cervical cancer screening strategy for HSIL(CIN2+) detection with superior diagnostic performance when compared with primary cytology-based models. Women <25 years might also benefit from an introduction to a more sensitive screening approach.

16.
Diagnostics (Basel) ; 11(8)2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34441354

RESUMO

The baseline data from the private-based opportunistic cervical cancer screening with HRHPV14, liquid-based cytology (LBC) and p16/Ki67 testing, and its quality assessment/quality control (QA/QC) tools are lacking. The age-stratified analysis of 30,066 screening tests results in a Polish population, including the investigation of HRHPV14 status, LBC, and p16/Ki67 dual-staining reporting rates, along with immediate histopathologic correlations, was conducted. For cytopathologic QA/QC, the College of American Pathologists (CAP) benchmarks and enhanced safety protocol were used. The NILM/ASC-US/LSIL/ASC-H/HSIL/AGC reporting rates were 93.9/3.4/2.0/0.22/0.24/0.11, respectively, with correlating HRHPV14-positive rates of 8.4/48.9/77.2/84.6/90.7/26.7. The reporting rates for HSIL (CIN2+) in HRHPV-positive women with NILM/ASC-US/LSIL/ASC-H/HSIL/AGC referred for a colposcopy with biopsy were 19.1/25.8/22.5/12.4/19.1/1.1% of the total HSIL (CIN2+). In total, of the 1130 p16/Ki67 tests, 30% were positive. In NILM HRHPV14-positive women with available histology result, HSIL(CIN2+) was detected in 28.3% of cases. In the first such large-scale Polish study presenting HRHPV14, informed LBC and HSIL (CIN2+) results, the reporting rates were highly consistent with data from American and other CAP-certified laboratories, confirming the possibility of using the 2019 ASCCP risk-based guidelines as one of the screening strategies outside of the US, in conditions of proper QA/QC. The private-based screening model can be effective in cervical cancer prevention, particularly in countries with low population coverage of public funds-based systems.

17.
J Med Chem ; 63(24): 15527-15540, 2020 12 24.
Artigo em Inglês | MEDLINE | ID: mdl-33078933

RESUMO

Chitotriosidase (CHIT1) and acidic mammalian chitinase (AMCase) are the enzymatically active chitinases that have been implicated in the pathology of chronic lung diseases such as asthma and interstitial lung diseases (ILDs), including idiopathic pulmonary fibrosis (IPF) and sarcoidosis. The clinical and preclinical data suggest that pharmacological inhibition of CHIT1 might represent a novel therapeutic approach in IPF. Structural modification of an advanced lead molecule 3 led to the identification of compound 9 (OATD-01), a highly active CHIT1 inhibitor with both an excellent PK profile in multiple species and selectivity against a panel of other off-targets. OATD-01 given orally once daily in a range of doses between 30 and 100 mg/kg showed significant antifibrotic efficacy in an animal model of bleomycin-induced pulmonary fibrosis. OATD-01 is the first-in-class CHIT1 inhibitor, currently completed phase 1b of clinical trials, to be a potential treatment for IPF.


Assuntos
Quitinases/antagonistas & inibidores , Inibidores Enzimáticos/uso terapêutico , Fibrose Pulmonar Idiopática/tratamento farmacológico , Piperidinas/química , Administração Oral , Animais , Sítios de Ligação , Bleomicina/toxicidade , Domínio Catalítico , Quitinases/metabolismo , Ensaios Clínicos Fase I como Assunto , Modelos Animais de Doenças , Cães , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacocinética , Feminino , Meia-Vida , Humanos , Fibrose Pulmonar Idiopática/induzido quimicamente , Fibrose Pulmonar Idiopática/patologia , Pulmão/metabolismo , Camundongos , Simulação de Acoplamento Molecular , Piperidinas/farmacocinética , Piperidinas/uso terapêutico , Ratos , Relação Estrutura-Atividade
18.
Physiol Plant ; 135(4): 351-64, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19292825

RESUMO

Infection with avirulent pathogens, tobacco mosaic virus (TMV) or Pseudomonas syringae pv. tabaci induced accumulation of polyisoprenoid alcohols, solanesol and a family of polyprenols [from polyprenol composed of 14 isoprene units (Pren-14) to -18, with Pren-16 dominating] in the leaves of resistant tobacco plants Nicotiana tabacum cv. Samsun NN. Upon TMV infection, solanesol content was increased seven- and eight-fold in the inoculated and upper leaves, respectively, while polyprenol content was increased 2.5- and 2-fold in the inoculated and upper leaves, respectively, on the seventh day post-infection. Accumulation of polyisoprenoid alcohols was also stimulated by exogenously applied hydrogen peroxide but not by exogenous salicylic acid (SA). On the contrary, neither inoculation of the leaves of susceptible tobacco plants nor wounding of tobacco leaves caused an increase in polyisoprenoid content. Taken together, these results indicate that polyisoprenoid alcohols might be involved in plant resistance against pathogens. A putative role of accumulated polyisoprenoids in plant response to pathogen attack is discussed. Similarly, the content of plastoquinone (PQ) was increased two-fold in TMV-inoculated and upper leaves of resistant plants. Accumulation of PQ was also stimulated by hydrogen peroxide, bacteria (P. syringae) and SA. The role of PQ in antioxidant defense in cellular membranous compartments is discussed in the context of the enzymatic antioxidant machinery activated in tobacco leaves subjected to viral infection. Elevated activity of several antioxidant enzymes (ascorbate peroxidase, guaiacol peroxidase, glutathione reductase and superoxide dismutase, especially the CuZn superoxide dismutase isoform) and high, but transient elevation of catalase was found in inoculated leaves of resistant tobacco plants but not in susceptible plants.


Assuntos
Álcoois/metabolismo , Nicotiana/metabolismo , Terpenos/metabolismo , Peróxido de Hidrogênio/farmacologia , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/metabolismo , Folhas de Planta/microbiologia , Folhas de Planta/virologia , Plastoquinona/metabolismo , Pseudomonas syringae/fisiologia , Ácido Salicílico/farmacologia , Estresse Fisiológico , Nicotiana/efeitos dos fármacos , Nicotiana/microbiologia , Nicotiana/virologia , Vírus do Mosaico do Tabaco/fisiologia
19.
Otolaryngol Pol ; 63(3): 245-8, 2009.
Artigo em Polonês | MEDLINE | ID: mdl-19886530

RESUMO

AIM: The aim of this work was to assessment the role of mould fungi and the allergy on fungi in chronic rhinosinusitis. MATERIAL AND METHODS: We studied 30 patients with chronic rhinosinusitis with or without polyposis who underwent endoscopic nose and sinuses procedures. Clinical and immunological workup was performed for atopy in all patients. We performed CT of the sinuses, skin-prick testing on 15 fungal allergens, total IgE and fungal-specific IgE levels, eosinophilia level. Specimens were sent for mycology and histopathologic analysis for identification of fungi. RESULTS: Fungal culture from sinuses were negative in all patients. Bacterial culture were positive in 19 cases. There was observed elevated total immunoglobulin E level in 70% of patients. Positive skin test reactivity for fungal allergen was observed in 7 patients--3 for Aspergillus, 2 for Alternaria and 2 for Cladosporium. Fungal specific IgE levels were below 0.35 KU/L in all patients. Nasal polyps were found in 26 patients, they were associated with asthma and aspirin intollerance. No fungal hyphae were found in histopathologic analysis. CONCLUSIONS: Our preliminary study suggest, that allergy for fungi doesn't play a significant role in etiology and pathogenesis of the chronic rhinosinusitis with or without polyps. We did't find any case of the allergic fungal sinusitis in our patients.


Assuntos
Fungos/isolamento & purificação , Micoses/microbiologia , Rinite/microbiologia , Sinusite/microbiologia , Adulto , Idoso , Contagem de Colônia Microbiana , Feminino , Humanos , Imunoglobulina E/análise , Masculino , Pessoa de Meia-Idade , Mucosa Nasal/microbiologia , Polônia , Rinite/diagnóstico , Rinite/cirurgia , Sinusite/diagnóstico , Sinusite/cirurgia , Testes Cutâneos , Tomografia Computadorizada por Raios X
20.
Chem Phys Lipids ; 147(2): 103-12, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17507003

RESUMO

A novel type of polyprenols, alloprenols, with an alpha-trans-isoprenoid unit was found in the leaves of Allophylus caudatus (Sapindaceae) besides typical alpha-cis-polyprenols. The polyprenol family (Prenol-11-13, Prenol-12 dominating) was accompanied by traces of dolichols of the same chain-length. Prenol alpha-cis- and alpha-trans-isomers were chromatographically separated and their structure was analyzed by HPLC/ESI-MS, HR-ESI-MS and 1H and 13C NMR spectroscopy. Model compounds, semi-synthetic alpha-isomers of all-trans-Pren-9 and mainly-cis-Pren-11, were obtained using an oxidation-reduction procedure. Comparison of their NMR spectra confirmed the structure of the newly identified polyprenols. The observed pattern of NMR signal shifts may be applied for elucidation of isoprenoid structure.


Assuntos
Pentanóis/química , Sapindaceae/química , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Hemiterpenos , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Espectrometria de Massas por Ionização por Electrospray
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