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1.
Biomed Khim ; 65(5): 407-417, 2019 Aug.
Artigo em Russo | MEDLINE | ID: mdl-31666414

RESUMO

Isatin (indol-2,3-dione), an endogenous biofactor found in the brain, peripheral tissues and biological body fluids of humans and animals, exhibits a wide range of biological and pharmacological activities. They are realized via interaction with numerous isatin-binding proteins. Some of these proteins identified during proteomic profiling of the brain are involved in the development of neurodegenerative pathology. In the context of the neuroprotective effect, the effect of isatin is comparable to the effects of deprenyl (selegiline), a pharmacological agent used for treatment of Parkinson's disease. In this study, we have investigated the effect of a single dose administration of isatin (100 mg/kg) and deprenyl (10 mg/kg) to mice on the profile of the brain isatin-binding proteins. Comparative proteomic analysis of brain isatin-binding proteins of mice treated with isatin or deprenyl resulted in identification of a representative group of proteins (n=200) sensitive to the administration of these substances. The change in the profile of isatin-binding proteins may be obviously attributed to accumulation of isatin and deprenyl in the brain and their interaction with target proteins; this prevents protein binding to the affinity sorbent. Thus identified brain isatin-binding proteins of the control animals obviously represent specific targets that interact directly with isatin (and also with deprenyl) in vivo. Isatin or deprenyl administered to animals interact with these proteins and thus inhibit their binding to the affinity sorbent (immobilized isatin analogue).


Assuntos
Encéfalo/efeitos dos fármacos , Proteínas de Transporte/metabolismo , Isatina/farmacologia , Fármacos Neuroprotetores/farmacologia , Selegilina/farmacologia , Animais , Encéfalo/metabolismo , Camundongos , Proteômica
2.
J Agric Food Chem ; 67(46): 12685-12695, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31657923

RESUMO

The meadow moth, Loxostege sticticalis, is a typical agricultural pest that uses sex pheromones to mediate mating behavior; however, the mechanism underlying the selectivity of its pheromone-binding proteins (PBPs) remains unknown. In this study, LstiPBP1 and LstiPBP3 were cloned, expressed, and purified, and the fluorescence binding assay showed that LstiPBP1 binds to the major sex pheromone component, E-11-tetradecenol (E11-14:OH), with high affinity; moreover, E11-14:OH could evoke a significant antennal electrophysiological response and attract L. sticticalis males. After LstiPBP1 was silenced, both the antennal response and attractiveness of E11-14:OH decreased significantly. Molecular docking predicted that a hydrogen bonding site, Leu37, played key role in the binding of LstiPBP1 to E11-14:OH. After Leu37 was mutated, the E11-14:OH-binding affinity decreased drastically. These results suggest that LstiPBP1 participates in E11-14:OH recognition and could be used as a target gene to disturb the mating behavior of L. sticticalis and develop new odorants for pest control.


Assuntos
Proteínas de Transporte/química , Proteínas de Insetos/química , Mariposas/metabolismo , Atrativos Sexuais/metabolismo , Animais , Sítios de Ligação , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Feminino , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Masculino , Simulação de Acoplamento Molecular , Mariposas/química , Mariposas/genética , Atrativos Sexuais/química
3.
Cell Physiol Biochem ; 53(5): 774-793, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31647207

RESUMO

BACKGROUND/AIMS: Deregulation of the complex interaction among host genetics, gut microbiota and environmental factors on one hand and aberrant immune responses on the other hand, are known to be associated with the development of inflammatory bowel disease. Recent studies provided strong evidence that autophagy plays a key role in the etiology of Crohn's disease (CD). Probiotics may exhibit many therapeutic properties, including anti-inflammatory abilities. While successful results have been obtained in ulcerative colitis patients, probiotics remain inefficient in CD for unknown reason. It remains therefore important to better understand their molecular mechanisms of action. METHODS: The activation of autophagy was examined by stimulating bone marrow-derived dendritic cells by the bacteria, followed by confocal microscopy and western blot analysis. The impact of blocking in vitro autophagy was performed in peripheral blood mononuclear cells using 3-methyl adenine or bafilomycin followed by cytokine secretion measurement by ELISA. The role of autophagy in the anti-inflammatory capacities of the bacterial strains was evaluated in vivo using an acute trinitrobenzene sulfonic acid-induced murine model of colitis. The impact of BMDC was evaluated by adoptive transfer, notably using bone marrow cells derived from autophagy-related 16-like 1-deficient mice. RESULTS: We showed that selected lactobacilli and bifidobacteria are able to induce autophagy activation in BMDCs. Blocking in vitro autophagy abolished the capacity of the strains to induce the release of the anti-inflammatory cytokine interleukin-10, while it exacerbated the secretion of the pro-inflammatory cytokine interleukin-1ß. We confirmed in the TNBS-induced mouse model of colitis that autophagy is involved in the protective capacity of these selected strains, and showed that dendritic cells are involved in this process. CONCLUSION: We propose autophagy as a novel mechanism involved in the regulatory capacities of probiotics.


Assuntos
Autofagia , Bifidobacterium/fisiologia , Lactobacillus/fisiologia , Adenina/análogos & derivados , Adenina/farmacologia , Animais , Proteínas Relacionadas à Autofagia , Células da Medula Óssea/citologia , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Quimiocinas/genética , Quimiocinas/metabolismo , Colite/induzido quimicamente , Colite/microbiologia , Colite/patologia , Citocinas/genética , Citocinas/metabolismo , Células Dendríticas/citologia , Células Dendríticas/metabolismo , Células Dendríticas/microbiologia , Feminino , Humanos , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/metabolismo , Macrolídeos/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout
4.
Nat Cell Biol ; 21(10): 1206-1218, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31548609

RESUMO

Cholesterol activates the master growth regulator, mTORC1 kinase, by promoting its recruitment to the surface of lysosomes by the Rag guanosine triphosphatases (GTPases). The mechanisms that regulate lysosomal cholesterol content to enable mTORC1 signalling are unknown. Here, we show that oxysterol binding protein (OSBP) and its anchors at the endoplasmic reticulum (ER), VAPA and VAPB, deliver cholesterol across ER-lysosome contacts to activate mTORC1. In cells lacking OSBP, but not other VAP-interacting cholesterol carriers, the recruitment of mTORC1 by the Rag GTPases is inhibited owing to impaired transport of cholesterol to lysosomes. By contrast, OSBP-mediated cholesterol trafficking drives constitutive mTORC1 activation in a disease model caused by the loss of the lysosomal cholesterol transporter, Niemann-Pick C1 (NPC1). Chemical and genetic inactivation of OSBP suppresses aberrant mTORC1 signalling and restores autophagic function in cellular models of Niemann-Pick type C (NPC). Thus, ER-lysosome contacts are signalling hubs that enable cholesterol sensing by mTORC1, and targeting the sterol-transfer activity of these signalling hubs could be beneficial in patients with NPC.


Assuntos
Colesterol/metabolismo , Retículo Endoplasmático/metabolismo , Lisossomos/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Doenças de Niemann-Pick/metabolismo , Receptores de Esteroides/metabolismo , Animais , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Células HEK293 , Humanos , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Glicoproteínas de Membrana/genética , Glicoproteínas de Membrana/metabolismo , Camundongos , Receptores de Esteroides/genética , Transdução de Sinais , Proteínas de Transporte Vesicular/genética , Proteínas de Transporte Vesicular/metabolismo
5.
Anticancer Res ; 39(9): 4795-4803, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31519581

RESUMO

BACKGROUND/AIM: To determine the mechanism of vitamin D3-induced modulation of antioxidant-related factors in endometrial cancer, we investigated their role in apoptosis of human endometrial cancer cells exposed to vitamin D3 Materials and Methods: The survival rate of human endometrial cancer cells was estimated after treatment with activated vitamin D3 Reactive oxygen species (ROS) levels were measured using flow cytometry. The levels of VDR, Trx, TXNIP and apoptosis-related proteins were investigated using western blotting and immunocytochemistry in human tissues. RESULTS: Treatment with D3 induced apoptotic cell death and cell-cycle arrest by increasing ROS concentration. Vitamin D3 inhibited proliferation of human endometrial cancer cells. It regulated intracellular ROS concentration in endometrial cancer cells via increased TXNIP expression. CONCLUSION: Antioxidant regulation via TXNIP is an important cell death mechanism in human endometrial cancer, and occurs via induction by vitamin D3.


Assuntos
Antioxidantes/metabolismo , Proteínas de Transporte/metabolismo , Neoplasias do Endométrio/metabolismo , Tiorredoxinas/metabolismo , Vitamina D/análogos & derivados , Apoptose/efeitos dos fármacos , Biomarcadores , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Neoplasias do Endométrio/tratamento farmacológico , Neoplasias do Endométrio/patologia , Feminino , Humanos , Imuno-Histoquímica , Oxirredução/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Vitamina D/farmacologia
6.
Adv Exp Med Biol ; 1155: 163-172, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31468395

RESUMO

Taurine (2-aminoethanesulfonic acid), a sulfur-containing ß-amino acid, is a free amino acid present in high concentrations in mammalian tissues. Taurine has pivotal roles in anti-oxidation, membrane stabilization, osmoregulation, anti-inflammation, and other process. In a DNA microarray analysis, we previously found that taurine markedly increases the mRNA expression of thioredoxin interacting protein (TXNIP) in Caco-2 cells. In this study, we investigated the effect of these taurine-induced changes in TXNIP on the function of Caco-2 cells. We found that taurine decreases glucose uptake in a dose-dependent manner. The taurine-induced decrease in glucose uptake was completely abolished by transfection with siRNA against TXNIP, suggesting that TXNIP is involved in the taurine-induced down-regulation of glucose uptake. We also revealed that taurine induces AMPK activation and further increases the intracellular ATP content in Caco-2 cells. These results suggest that taurine could regulate the function of Caco-2 cells via TXNIP induction, leading to extend our understanding of the functions of taurine.


Assuntos
Proteínas de Transporte/metabolismo , Glucose/metabolismo , Taurina/farmacologia , Trifosfato de Adenosina/metabolismo , Adenilato Quinase/metabolismo , Transporte Biológico , Células CACO-2 , Regulação para Baixo , Humanos , RNA Interferente Pequeno
7.
J Cancer Res Clin Oncol ; 145(9): 2241-2250, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31342168

RESUMO

PURPOSE: The tripartite motif (TRIM)16 acts as a tumour suppressor in both squamous cell carcinoma (SCC) and melanoma. TRIM16 is known to be secreted by keratinocytes, but no studies have been reported yet to assess the relationship between TRIM16 keratinocyte expression and melanoma development. METHODS: To study the role of TRIM16 in skin cancer development, we developed a keratinocyte TRIM16-specific knockout mouse model, and used the classical two-stage skin carcinogenesis challenge method, to assess the loss of keratinocyte TRIM16 on both papilloma, SCC and melanoma development in the skin after topical carcinogen treatment. RESULTS: Heterozygous, but not homozygous, TRIM16 knockout mice exhibited an accelerated development of skin papillomas and melanomas, larger melanoma lesions and an increased potential for lymph node metastasis. CONCLUSION: This study provides the first evidence that keratinocyte loss of the putative melanoma tumour suppressor protein, TRIM16, enhances melanomagenesis. Our data also suggest that TRIM16 expression in keratinocytes is involved in cross talk between keratinocytes and melanocytes, and has a role in melanoma tumorigenesis.


Assuntos
Proteínas de Transporte/genética , Queratinócitos/metabolismo , Perda de Heterozigosidade/fisiologia , Linfonodos/metabolismo , Melanócitos/metabolismo , Melanoma/genética , Neoplasias Cutâneas/genética , Animais , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Proteínas de Transporte/metabolismo , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/patologia , Células Cultivadas , Regulação Neoplásica da Expressão Gênica , Queratinócitos/patologia , Linfonodos/patologia , Metástase Linfática , Melanócitos/patologia , Melanoma/metabolismo , Melanoma/patologia , Camundongos , Camundongos Knockout , Pele/metabolismo , Pele/patologia , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologia
8.
J Sci Food Agric ; 99(14): 6582-6588, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31328268

RESUMO

BACKGROUND: This study was conducted to investigate effects of dietary zinc methionine (Zn-Met) supplementation on laying performance, zinc (Zn) status, intestinal morphology, and Zn transporters in laying hens compared with zinc sulfate (ZnSO4 ). A total of 384 Hyline Grey laying hens (38 weeks old) with similar performance (1.42 ± 0.07 kg) were randomly allotted to four dietary treatments and fed with a basal diet (control) or the basal diet supplemented with Zn, either as Zn-Met at 40 and 80 mg Zn/kilogram diet or as ZnSO4 at 80 mg Zn/kilogram diet, for 10 weeks. RESULTS: There was no difference in egg weight, egg production, feed intake, and feed conversation ratio among all groups (P > 0.05). Compared with the control, Zn contents were increased (P < 0.05) in the liver, duodenum, and jejunum of laying hens fed diets supplemented with different Zn sources. There was no difference (P > 0.05) in Zn contents in liver, duodenum, and jejunum between diets supplemented with Zn-Met or ZnSO4 at 80 mg Zn/kilogram diet. Compared with the control and the ZnSO4 group (80 mg Zn/kilogram diet), supplementation with Zn-Met of 80 mg Zn/kilogram diet increased (P < 0.05) villus height, villus area, and villus height/crypt depth ratio but reduced (P < 0.05) crypt depth in jejunum. Expression of metallothionein messenger RNA of jejunum in the group fed a diet containing Zn-Met (80 mg Zn/kilogram diet) was higher (P < 0.05) than that in the control. CONCLUSION: These results indicated that Zn-Met has positive effects on the Zn status of liver, duodenum, and jejunum, intestinal morphology, and metallothionein messenger RNA expression in jejunum of laying hens compared with ZnSO4 . © 2019 Society of Chemical Industry.


Assuntos
Proteínas de Transporte/genética , Galinhas/crescimento & desenvolvimento , Galinhas/metabolismo , Intestinos/crescimento & desenvolvimento , Metionina/análogos & derivados , Compostos Organometálicos/administração & dosagem , Zinco/metabolismo , Ração Animal/análise , Animais , Proteínas de Transporte/metabolismo , Galinhas/genética , Suplementos Nutricionais/análise , Ovos/análise , Feminino , Intestinos/efeitos dos fármacos , Metionina/administração & dosagem , Metionina/metabolismo , Compostos Organometálicos/metabolismo , Zinco/análise
9.
Oncology ; 97(3): 180-188, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31330520

RESUMO

BACKGROUND: Hormone receptor-positive breast cancer accounts for nearly two-thirds of breast cancer cases; it ultimately acquires resistance during endocrine treatment and becomes more aggressive. This study evaluated the role of developmental endothelial locus (Del)-1 in tamoxifen-resistant (TAM-R) breast cancer. METHODS: Del-1 expression in recurrent TAM-R breast cancer tissue was evaluated and compared to that in the original tumor tissue from the same patients. Del-1 expression was also evaluated in TAM-R cells by quantitative real-time PCR, western blotting, and enzyme-linked immunosorbent assay. The effects of Del-1 knockdown on the proliferation, migration, and invasion of TAM-R cells was assessed with wound-healing and Matrigel transwell assays. RESULTS: Del-1 was more highly expressed in recurrent breast cancer as compared to the original tumor tissues before initiation of endocrine treatment. Del-1 mRNA was upregulated in TAM-R and small interfering RNA-mediated knockdown of Del-1 suppressed the migration and proliferation of TAM-R cells while partly restoring TAM sensitivity. And the TAM resistance was recovered by knockdown of Del-1. CONCLUSIONS: TAM-R breast cancer is characterized by Del-1 overexpression and tumor progression can be inhibited by Del-1 depletion, which restores TAM sensitivity. Thus, therapeutic strategies that target Del-1 may be effective for the treatment of hormone-resistant breast cancer.


Assuntos
Antineoplásicos Hormonais/farmacologia , Neoplasias da Mama/genética , Proteínas de Transporte/genética , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica , Tamoxifeno/farmacologia , Neoplasias da Mama/metabolismo , Proteínas de Transporte/metabolismo , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ensaio de Imunoadsorção Enzimática , Feminino , Técnicas de Silenciamento de Genes , Humanos , Interferência de RNA , RNA Interferente Pequeno
10.
Acta Gastroenterol Belg ; 82(2): 285-290, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31314190

RESUMO

BACKGROUND AND AIM: Intestinal barrier dysfunction has been implicated in the development of infectious complications of acute pancreatitis. Nucleotide-Binding Oligomerization DomainContaining Protein 2 (NOD2) plays an important role in the proper functioning of intestinal defense mechanisms. Here, we investigated the frequency of NOD2 variants in patients with mild and severe acute pancreatitis. MATERIALS AND METHODS: Groups 1, 2 and 3 comprised healthy participants and patients with mild and severe pancreatitis, respectively. Four NOD2 variants and serum interleukin-6 (IL-6), Tumor Necrosis Factor-a (TNF-a) and lipopolysaccharide-binding protein (LBP) levels were analyzed. RESULTS: Three patients (3/32, 9.4%) in the severe pancreatitis group were positive for the p.R702W variant. This variant was negative in other groups. One, three and three patients in the healthy (1/27, 3.7%), mild (3/36, 8.3%) and severe pancreatitis (3/32, 9.4%) groups tested positive for the 1007fs variant, respectively. No significant differences in the frequencies of NOD2 variants were evident among the groups. Serum IL-6, TNF-a and LBP levels were markedly higher in the severe pancreatitis than the healthy and mild pancreatitis groups (all p<0.001). We observed no significant correlation between cytokine levels and NOD2 variants. CONCLUSION: Our results support an association between the presence of the p.R702W variant and severe pancreatitis.


Assuntos
Proteínas de Transporte/sangue , Interleucina-6/sangue , Glicoproteínas de Membrana/sangue , Proteína Adaptadora de Sinalização NOD2/metabolismo , Pancreatite/sangue , Fator de Necrose Tumoral alfa/sangue , Doença Aguda , Proteínas da Fase Aguda/metabolismo , Proteínas de Transporte/metabolismo , Estudos de Casos e Controles , Voluntários Saudáveis , Humanos , Interleucina-6/metabolismo , Intestinos , Glicoproteínas de Membrana/metabolismo , Nucleotídeos , Pancreatite/diagnóstico , Índice de Gravidade de Doença , Fator de Necrose Tumoral alfa/metabolismo
11.
Anticancer Res ; 39(7): 3347-3351, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31262855

RESUMO

BS69 is encoded by a gene located on chromosome 10, in a region frequently deleted in human cancers and BS69 expression is often down-regulated in human cancers. In addition, BS69 acts as a transcriptional repressor via interaction with transcriptional factors associated with tumorigenesis, such as cellular homolog of the avian myeloblastosis viral oncoprotein, v-ets erythroblastosis virus E26 oncogene homolog 2 oncoprotein, MYC-associated protein X gene-associated protein. Overexpression of BS69 can suppress proliferation of osteosarcoma, breast cancer and glioma cells in vitro; and inhibits tumor growth in xenograft models. Therefore, BS69 may act as a tumor suppressor, and may be a new target for cancer therapy. However, BS69 down-regulation has been found to be involved in cellular senescence and is associated with the reversion of the malignant phenotype of breast cancer cells. Therefore, additional studies are necessary to clarify the role of BS69 in tumor development.


Assuntos
Proteínas de Transporte/metabolismo , Neoplasias/metabolismo , Animais , Senescência Celular , Humanos , Proteínas Supressoras de Tumor/metabolismo
12.
Inorg Chem ; 58(20): 13604-13618, 2019 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-31273981

RESUMO

[NiFe]-hydrogenase enzymes catalyze the reversible oxidation of hydrogen at a bimetallic cluster and are used by bacteria and archaea for anaerobic growth and pathogenesis. Maturation of the [NiFe]-hydrogenase requires several accessory proteins to assemble and insert the components of the active site. The penultimate maturation step is the delivery of nickel to a primed hydrogenase enzyme precursor protein, a process that is accomplished by two nickel metallochaperones, the accessory protein HypA and the GTPase HypB. Recent work demonstrated that nickel is rapidly transferred to HypA from GDP-loaded HypB within the context of a protein complex in a nickel selective and unidirectional process. To investigate the mechanism of metal transfer, we examined the allosteric effects of nucleotide cofactors and partner proteins on the nickel environments of HypA and HypB by using a combination of biochemical, microbiological, computational, and spectroscopic techniques. We observed that loading HypB with either GDP or a nonhydrolyzable GTP analogue resulted in a similar nickel environment. In addition, interaction with a mutant version of HypA with disrupted nickel binding, H2Q-HypA, does not induce substantial changes to the HypB G-domain nickel site. Instead, the results demonstrate that HypB modifies the acceptor site of HypA. Analysis of a peptide maquette derived from the N-terminus of HypA revealed that nickel is predominately coordinated by atoms from the N-terminal Met-His motif. Furthermore, HypA is capable of two nickel-binding modes at the N-terminus, a HypB-induced mode and a binding mode that mirrors the peptide maquette. Collectively, these results reveal that HypB brings about changes in the nickel coordination of HypA, providing a mechanism for the HypB-dependent control of the acquisition and release of nickel by HypA.


Assuntos
Proteínas de Transporte/química , Complexos de Coordenação/química , Proteínas de Escherichia coli/química , Escherichia coli/enzimologia , Níquel/química , Proteínas de Transporte/metabolismo , Complexos de Coordenação/metabolismo , Proteínas de Escherichia coli/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular , Modelos Moleculares , Níquel/metabolismo
13.
Nat Chem Biol ; 15(8): 795-802, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31308531

RESUMO

Glycosylation is a common modification reaction in natural product biosynthesis and has been known to be a post-assembly line tailoring process in glycosylated polyketide biosynthesis. Here, we show that in pactamycin biosynthesis, glycosylation can take place on an acyl carrier protein (ACP)-bound polyketide intermediate. Using in vivo gene inactivation, chemical complementation and in vitro pathway reconstitution, we demonstrate that the 3-aminoacetophenone moiety of pactamycin is derived from 3-aminobenzoic acid by a set of discrete polyketide synthase proteins via a 3-(3-aminophenyl)3-oxopropionyl-ACP intermediate. This ACP-bound intermediate is then glycosylated by an N-glycosyltransferase, PtmJ, providing a sugar precursor for the formation of the aminocyclopentitol core structure of pactamycin. This is the first example of glycosylation of a small molecule while tethered to a carrier protein. Additionally, we demonstrate that PtmO is a hydrolase that is responsible for the release of the ACP-bound product to a free ß-ketoacid that subsequently undergoes decarboxylation.


Assuntos
Proteínas de Transporte/metabolismo , Pactamicina/biossíntese , Streptomyces/metabolismo , Proteínas de Bactérias , Proteínas de Transporte/química , Clonagem Molecular , Regulação Bacteriana da Expressão Gênica , Policetídeo Sintases/genética , Policetídeo Sintases/metabolismo , Policetídeos/química , Ligação Proteica
14.
Cell Physiol Biochem ; 53(1): 200-214, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31287628

RESUMO

BACKGROUND/AIMS: Skeletal mass loss is reported in several catabolic conditions and it has been associated with a reduced intracellular L-glutamine content. We investigated the association of intracellular L-glutamine concentration with the protein content in skeletal muscle cells. METHODS: We cultivated C2C12 myotubes in the absence or presence of 2 (reference condition), 8 or 16 mM L-glutamine for 48 hours, and the variations in the contents of amino acids and proteins measured. We used an inhibitor of L-glutamine synthesis (L-methionine sulfoximine - MSO) to promote a further reduction in intracellular L-glutamine levels. Amino acids contents in cells and media were measured using LC-MS/MS. We measured changes in phosphorylated Akt, RP-S6, and 4E-BP1contents in the absence or presence of insulin by western blotting. RESULTS: Reduced intracellular L-glutamine concentration was associated with decreased protein content and increased protein breakdown. Low intracellular glutamine levels were also associated with decreased p-Akt contents in the presence of insulin. A further decrease in intracellular L-glutamine caused by glutamine synthetase inhibitor reduced protein content and levels of amino acids generated from glutamine metabolism and increased bAib still further. Cells exposed to high medium glutamine levels did not have any change in protein content but exhibited increased contents of the amino acids derived from L-glutamine metabolism. CONCLUSION: Intracellular L-glutamine levels per se play a role in the control of protein content in skeletal muscle myotubes.


Assuntos
Proteínas de Transporte/metabolismo , Glutamina/metabolismo , Insulina/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Fosfoproteínas/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteína S6 Ribossômica/metabolismo , Animais , Proteínas de Transporte/análise , Proteínas de Ciclo Celular , Linhagem Celular , Cromatografia Líquida , Fatores de Iniciação em Eucariotos , Glutamina/análise , Insulina/análise , Camundongos , Fibras Musculares Esqueléticas/química , Fosfoproteínas/análise , Fosforilação , Proteínas Proto-Oncogênicas c-akt/análise , Proteína S6 Ribossômica/análise , Espectrometria de Massas em Tandem
15.
J Clin Pathol ; 72(10): 696-704, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31331953

RESUMO

AIMS: Zinc-alpha 2-glycoprotein (AZGP1) is a promising tissue biomarker to predict outcomes in men undergoing treatment for localised prostate cancer (PCa). We aimed to examine the association between AZGP1 expression and the endpoints: risk of biochemical failure (BF), initiating castration-based treatment, developing castration-resistant PCa (CRPC) and PCa-specific mortality following radical prostatectomy (RP). METHODS: The study included a prospective cohort of 302 patients who underwent RP for PCa from 2002 to 2005. AZGP1 expression was analysed using immunohistochemistry on tissue microarray RP specimens and was scored semiquantitively as low or high expression. Risk of all endpoints was analysed using stratified cumulative incidences and cause-specific Cox regression, and validated with receiver operating curves, calibration and discrimination in competing-risk analyses. A meta-analysis was performed including previous studies investigating AZGP1 expression and risk of BF following RP. RESULTS: Median time of follow-up was 14.0 years. The cumulative incidence of all endpoints was significantly higher in patients with low AZGP1 expression compared with patients with high AZGP1 expression (p<0.001). In a multivariate analysis, low AZGP1 expression increases the risk of BF (HR 2.7; 95% CI 1.9 to 3.8; p<0.0001), castration-based treatment (HR 2.2; 95% CI 1.2 to 4.2; p=0.01) and CRPC (HR 2.3; 95% CI 1.1 to 5.0; p=0.03). Validation showed a low risk of prediction error and a high model performance for all endpoints. In a meta-analysis, low AZGP1 was associated with BF (HR 1.7; 95% CI 1.2 to 2.5). CONCLUSIONS: Low AZGP1 expression is associated with the risk of aggressive time-dependent outcomes in men undergoing RP for localised PCa.


Assuntos
Biomarcadores Tumorais/metabolismo , Proteínas de Transporte/metabolismo , Glicoproteínas/metabolismo , Neoplasias da Próstata/metabolismo , Estudos de Coortes , Humanos , Imuno-Histoquímica , Masculino , Análise Multivariada , Estudos Prospectivos , Próstata/metabolismo , Próstata/patologia , Prostatectomia , Neoplasias da Próstata/cirurgia , Análise Serial de Tecidos
16.
Toxicol Lett ; 313: 108-119, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31251971

RESUMO

Polychlorinated biphenyls (PCBs) are classic persistent organic pollutants (POPs) and are associated with the progression of many cancers, including liver cancer. The present study investigated the effect of 2,3'4,4',5-pentachlorobiphenyl (PCB118) on hepatocellular carcinoma cell proliferation and its underlying mechanisms. The results indicated that PCB118 exposure promotes the proliferation and glycolysis of hepatocellular carcinoma SMMC-7721 cells. Moreover, PCB118 exposure increased the expression level of pyruvate kinase M2 (PKM2) and its nuclear translocation, whereas treatment with PKM2 shRNA suppressed the induction of cell proliferation and glycolysis by PCB118. PCB118 stimulated reactive oxygen species (ROS) production by activating nicotinamide adenine dinucleotide phosphate (NADPH) oxidase. Treatment with the antioxidants N-acetyl-L-cysteine (NAC) and superoxide dismutase (SOD) prevented PCB118-induced effects on PKM2, cell proliferation and glycolysis. Furthermore, we found that PCB118 activated NADPH oxidase through the aryl hydrocarbon receptor (AhR) in SMMC-7721 cells. Consistently, treatment with AhR shRNA suppressed PCB118-induced effects on PKM2, cell proliferation and glycolysis. Overall, these results indicated that PCB118 promotes HCC cell proliferation via PKM2-dependent upregulation of glycolysis, which is mediated by AhR/NADPH oxidase-induced ROS production.


Assuntos
Carcinógenos Ambientais/toxicidade , Carcinoma Hepatocelular/enzimologia , Proteínas de Transporte/metabolismo , Proliferação de Células/efeitos dos fármacos , Glicólise/efeitos dos fármacos , Neoplasias Hepáticas/enzimologia , Proteínas de Membrana/metabolismo , Bifenilos Policlorados/toxicidade , Hormônios Tireóideos/metabolismo , Transporte Ativo do Núcleo Celular , Fatores de Transcrição Hélice-Alça-Hélice Básicos/agonistas , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Proteínas de Transporte/genética , Linhagem Celular Tumoral , Humanos , Neoplasias Hepáticas/patologia , Proteínas de Membrana/genética , NADPH Oxidases/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Receptores de Hidrocarboneto Arílico/agonistas , Receptores de Hidrocarboneto Arílico/genética , Receptores de Hidrocarboneto Arílico/metabolismo , Transdução de Sinais/efeitos dos fármacos , Hormônios Tireóideos/genética
17.
Life Sci ; 231: 116593, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31228512

RESUMO

Inflammasomes are the major mechanistic complexes that include members of the NOD-like receptor (NLRs) or AIM2-like receptors (ALRs) families, which are affiliated with the innate immune system. Once NLRs or ALRs are activated by pathogen-associated molecular patterns (PAMPs) or damage-associated molecular patterns (DAMPs), the caspase-1 or -11 is activated by binding with NLRs or ALRs via its own unique cytosolic domains. As a result, caspase-1 or -11 enhances the production of IL-1ß and IL-18, which results in inflammation via the recruitment of immune cells, such as macrophages, and the promotion of programmed cell death mechanisms such as pyroptosis. In addition, the consistent cascades of inflammasomes would precede both minor and severe autoimmune diseases and cancers. The clinical relevance of inflammasomes in multiple forms of cancer highlights their therapeutic promise as molecular targets. To closely analyze the physiological roles of inflammasomes in cancers, here, we describe the fundamental knowledge regarding the current issues of inflammasomes in relevant cancers, and discuss possible therapeutic values in targeting these inflammasomes for the prevention and treatment of cancer.


Assuntos
Inflamassomos/metabolismo , Inflamassomos/fisiologia , Neoplasias/terapia , Alarminas/metabolismo , Animais , Apoptose/fisiologia , Doenças Autoimunes/imunologia , Proteínas de Transporte/metabolismo , Caspase 1/metabolismo , Caspases/metabolismo , Humanos , Imunidade Inata/imunologia , Inflamação/imunologia , Interleucina-18/metabolismo , Interleucina-1beta/metabolismo , Proteínas NLR/fisiologia , Padrões Moleculares Associados a Patógenos/metabolismo , Transdução de Sinais
18.
Biochemistry (Mosc) ; 84(4): 346-357, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31228926

RESUMO

Sterols are important components of biological membranes that determine the physicochemical properties of lipid bilayer and regulate the functioning of membrane proteins. Being insoluble in water, sterols cannot diffuse between the membrane compartments separated by an aqueous phase. For this reason, distribution of sterols across cellular membranes is rather uneven. Membrane-to-membrane transport of sterols occurs mainly in a non-vesicular fashion and is provided by Lam and Osh proteins. In this review, we discuss the consequences of impairments in sterol biosynthesis and transport mostly relying on the studies performed on the model organism Saccharomyces cerevisiae. Despite the fact that molecular mechanisms underlying the functioning of Lam and Osh proteins are well established, the biological roles of these proteins are still unclear, because deletions of corresponding genes do not affect yeast phenotype. At the same time, disruptions in the biosynthesis of ergosterol, the major sterol of S. cerevisiae, lead to either cell death or reduced stress resistance. However, under certain conditions (e.g., mild salt or thermal stresses), a decrease in the ergosterol levels causes an increase in cell resistance. This suggests that the cells possess a mechanism facilitating rapid adjustment of the plasma membrane sterol content. We argue that the biological role of Lam proteins is, in particular, fast optimization of sterol composition of cell membranes.


Assuntos
Ergosterol/metabolismo , Saccharomyces cerevisiae/metabolismo , Transporte Biológico , Proteínas de Transporte/metabolismo , Membrana Celular/metabolismo , Retículo Endoplasmático/metabolismo , Ergosterol/biossíntese , Proteínas de Membrana/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Esqualeno/metabolismo , Esteróis/metabolismo
19.
Nucleic Acids Res ; 47(15): 7901-7913, 2019 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-31219592

RESUMO

Guanine-rich DNA strands can fold into non-canonical four-stranded secondary structures named G-quadruplexes (G4). Experimental evidences suggest that G4-DNA surrounding transcription start sites act as cis-regulatory elements by either stimulating or inhibiting gene transcription. Therefore, proteins able to target and regulate specific G4 formation/unfolding are crucial for G4-mediated transcriptional control. Here we present data revealing that CNBP acts in vitro as a G4-unfolding protein over a tetramolecular G4 formed by the TG4T oligonucleotide, as well as over the G4 folded in the promoters of several oncogenes. CNBP depletion in cellulo led to a reduction in the transcription of endogenous KRAS, suggesting a regulatory role of CNBP in relieving the transcriptional abrogation due to G4 formation. CNBP activity was also assayed over the evolutionary conserved G4 enhancing the transcription of NOGGIN (NOG) developmental gene. CNBP unfolded in vitro NOG G4 and experiments performed in cellulo and in vivo in developing zebrafish showed a repressive role of CNBP on the transcription of this gene by G4 unwinding. Our results shed light on the mechanisms underlying CNBP way of action, as well as reinforce the notion about the existence and function of G4s in whole living organisms.


Assuntos
DNA/química , Quadruplex G , Proteínas de Ligação a RNA/genética , Transcrição Genética , Proteínas de Peixe-Zebra/genética , Animais , Animais Geneticamente Modificados , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , DNA/genética , DNA/metabolismo , Embrião não Mamífero , Regulação da Expressão Gênica , Genes Reporter , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Células HeLa , Humanos , Regiões Promotoras Genéticas , Ligação Proteica , Proteínas de Ligação a RNA/metabolismo , Peixe-Zebra , Proteínas de Peixe-Zebra/metabolismo
20.
Nat Commun ; 10(1): 2707, 2019 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-31222004

RESUMO

Bone metastases occur in most advanced breast cancer patients and cause serious skeletal-related complications. The mechanisms by which bone metastasis seeds develop in primary tumors and specifically colonize the bone remain to be elucidated. Here, we show that forkhead box F2 (FOXF2) functions as a master transcription factor for reprogramming cancer cells into an osteomimetic phenotype by pleiotropic transactivation of the BMP4/SMAD1 signaling pathway and bone-related genes that are expressed at early stages of bone differentiation. The epithelial-to-osteomimicry transition regulated by FOXF2 confers a tendency on cancer cells to metastasize to bone which leads to osteolytic bone lesions. The BMP antagonist Noggin significantly inhibits FOXF2-driven osteolytic bone metastasis of breast cancer cells. Thus, targeting the FOXF2-BMP/SMAD axis might be a promising therapeutic strategy to manage bone metastasis. The role of FOXF2 in transactivating bone-related genes implies a biological function of FOXF2 in regulating bone development and remodeling.


Assuntos
Neoplasias Ósseas/patologia , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Fatores de Transcrição Forkhead/metabolismo , Regulação Neoplásica da Expressão Gênica , Animais , Proteína Morfogenética Óssea 4/metabolismo , Neoplasias Ósseas/genética , Neoplasias Ósseas/secundário , Neoplasias da Mama/cirurgia , Carcinoma Ductal de Mama/genética , Carcinoma Ductal de Mama/secundário , Proteínas de Transporte/metabolismo , Linhagem Celular Tumoral , Reprogramação Celular/genética , Feminino , Seguimentos , Perfilação da Expressão Gênica , Humanos , Camundongos , Camundongos Nus , Osteoblastos , Transdução de Sinais/genética , Proteína Smad1/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
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