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1.
Int J Mol Sci ; 24(15)2023 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-37569569

RESUMO

Testicular cancer is the most prevalent tumor among males aged 15 to 35, resulting in a significant number of newly diagnosed cases and fatalities annually. Non-coding RNAs (ncRNAs) have emerged as key regulators in various cellular processes and pathologies, including testicular cancer. Their involvement in gene regulation, coding, decoding, and overall gene expression control suggests their potential as targets for alternative treatment approaches for this type of cancer. Furthermore, epigenetic modifications, such as histone modifications, DNA methylation, and the regulation by microRNA (miRNA), have been implicated in testicular tumor progression and treatment response. Epigenetics may also offer critical insights for prognostic evaluation and targeted therapies in patients with testicular germ cell tumors (TGCT). This comprehensive review aims to present the latest discoveries regarding the involvement of some proteins and ncRNAs, mainly miRNAs and lncRNA, in the epigenetic aspect of testicular cancer, emphasizing their relevance in pathogenesis and their potential, given the fact that their specific expression holds promise for prognostic evaluation and targeted therapies.


Assuntos
MicroRNAs , Neoplasias Embrionárias de Células Germinativas , Neoplasias Testiculares , Masculino , Humanos , Neoplasias Testiculares/genética , RNA não Traduzido/genética , RNA não Traduzido/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Epigênese Genética , Neoplasias Embrionárias de Células Germinativas/genética
2.
Mediators Inflamm ; 2019: 9130868, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31827384

RESUMO

Major depressive disorder (MDD) has a prevalence of 5% in adolescents. Several studies have described the association between the inflammatory response and MDD, but little is known about the relationship between MDD and growth factors, such as IL-7, IL-9, IL-17A, VEGF, basic FGF, G-CSF, and GM-CSF. It must be appointed that there are scarce reports on growth factors in adolescents with MDD and even fewer with a clinical follow-up. In this work, we evaluated the levels of growth factors (IL-7, IL-9, IL-17A, VEGF, basic FGF, G-CSF, and GM-CSF) in MDD adolescents and the clinical follow-up during eight weeks of treatment with fluoxetine. Methods. All patients were diagnosed according to the DSM-IV-TR, and the severity of the symptoms was evaluated using the Hamilton Depression Rating Scale (HDRS). Growth factors IL-7, IL-9, IL-17A, VEGF, basic FGF, G-CSF, and GM-CSF were quantified by cytometric bead array using serum samples from 22 adolescents with MDD and 18 healthy volunteers. Results. All patients showed clinical improvement since the fourth week of pharmacological treatment according to the HDRS. Considerably higher levels of IL-7, IL-9, IL-17A, VEGF, basic FGF, G-CSF, and GM-CSF were detected in MDD adolescents as compared to healthy volunteers. A significant but temporal decrease was detected in basic FGF, G-CSF, and GM-CSF at week four of fluoxetine administration. Conclusions. To the best of our knowledge, this is the first report to show alterations in the levels of growth factors, such as IL-7, IL-9, IL-17A, VEGF, basic FGF, G-CSF, and GM-CSF in MDD adolescents during eight weeks of clinical follow-up. These disturbances might be involved in the physiopathology of MDD since such growth factors have been proven to participate in the neural development and correct functioning of the CNS; therefore, subtle alterations in it may contribute to MDD.


Assuntos
Transtorno Depressivo Maior/tratamento farmacológico , Fluoxetina/uso terapêutico , Adolescente , Adulto , Transtorno Depressivo Maior/sangue , Feminino , Fator 2 de Crescimento de Fibroblastos/sangue , Fator Estimulador de Colônias de Granulócitos/sangue , Fator Estimulador de Colônias de Granulócitos e Macrófagos/sangue , Humanos , Interleucina-17/sangue , Interleucina-7/sangue , Interleucina-9/sangue , Estudos Longitudinais , Masculino , Fator A de Crescimento do Endotélio Vascular/sangue , Adulto Jovem
3.
Biometals ; 32(6): 887-899, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31586273

RESUMO

Metallothioneins (MTs) have been identified in a wide variety of organisms from bacteria to humans. The biological functions of these MTs have a key role in metalloregulatory metabolism and its expression is induced in response to different stimuli, particularly by divalent metal cations. Also, the action of MTs have been implicated in the survival of pathogens in presence of microbicidal concentration of divalent cations, which allows the establishment of the infection. Trichomonas vaginalis is a protozoan parasite that adapts to the microenvironment of the male urogenital tract, where cations such as zinc (Zn2+) and cadmium (Cd2+) are present. Nevertheless, the molecular mechanisms of metal tolerance and homeostasis is not yet dilucidated in this parasite. In this study, we have identified 4 potential MT-like sequences (tvmt´s) in T. vaginalis genome. Because tvmt-2, -3, and -4 corresponds to truncated partial genes, we characterized the trichomonad tvmt-1 gene. The bioinformatic analyses and the predicted protein (TvMT-1) show similar properties to the reported in other MTs. The expression patterns of tvmt-1 in the presence of several divalent cations (Fe2+, Mn2+, Zn2+ and Cd2+) were analyzed and we demonstrated that Cd2+ induce significantly their expression. By indirect immunofluorescence assays, we corroborated this positive regulation of TvMT-1 in the cytoplasm of parasites grown in the presence of Cd2+. The tvmt-1 promoter contains putative metal responsive elements, which are probably the responsible for the Cd2+-dependent expression of this gene. Our results suggest that tvmt-1 gene encode a metallothionein that may be responsible for the homeostatis and detoxification of Cd+2 in T. vaginalis.


Assuntos
Cádmio/farmacologia , Metalotioneína/genética , Trichomonas vaginalis/efeitos dos fármacos , Trichomonas vaginalis/genética , Homeostase/efeitos dos fármacos , Metalotioneína/metabolismo , Trichomonas vaginalis/metabolismo
4.
Front Oncol ; 9: 1370, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31921634

RESUMO

During angiogenesis, new vessels emerge from existing endothelial lined vessels to promote the degradation of the vascular basement membrane and remodel the extracellular matrix (ECM), followed by endothelial cell migration, and proliferation and the new generation of matrix components. Matrix metalloproteinases (MMPs) participate in the disruption, tumor neovascularization, and subsequent metastasis while tissue inhibitors of metalloproteinases (TIMPs) downregulate the activity of these MMPs. Then, the angiogenic response can be directly or indirectly mediated by MMPs through the modulation of the balance between pro- and anti-angiogenic factors. This review analyzes recent knowledge on MMPs and their participation in angiogenesis.

5.
Mediators Inflamm ; 2018: 4074051, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30662368

RESUMO

Changes in cytokine levels in major depression and during treatment have been reported in adults. However, few studies have examined cytokine levels in an adolescent sample despite this being a common age of onset. Methods. We measured proinflammatory (IL-2, IFN-γ, IL-1ß, TNF-α, IL-6, IL-12, and IL-15) and anti-inflammatory (IL-4, IL-5, IL-13, IL-1Ra, and IL-10) cytokine serum levels in 22 adolescents with major depression and 18 healthy volunteers. Cytokines were measured by multiplex bead-based immunoassays at baseline, and 4 and 8 weeks after commencement of fluoxetine administration in the clinical group. Results. Compared to healthy volunteers, adolescents with major depression at baseline showed significant increases in all pro- and anti-inflammatory cytokines, except IL-1Ra and IL-10. Significant changes were observed in fluoxetine treatment compared to baseline: proinflammatory cytokines IFN-γ, IL-1ß, TNF-α, IL-6, IL-12, and IL-15 were decreased only at week 4 whereas IL-2 was increased only at week 8; anti-inflammatory cytokines IL-4 and IL-5 were increased at week 8 while IL-1Ra was reduced only at week 4. There were no significant correlations between cytokine levels and symptomatic improvement in HDRS. Discussion. The results suggest a significant interplay between cytokine levels, the depressive state, and the stage of treatment with an SSRI. To the best of our knowledge, this is the first report in depressed adolescents with elevated IL-12, IL-13, and IL-15 levels. Further studies are necessary to clarify the role and mechanisms of altered cytokine levels in the pathogenesis and physiopathology of major depressive disorder.


Assuntos
Antidepressivos de Segunda Geração/uso terapêutico , Transtorno Depressivo Maior/tratamento farmacológico , Fluoxetina/uso terapêutico , Adolescente , Adulto , Citocinas/sangue , Depressão/sangue , Depressão/tratamento farmacológico , Depressão/imunologia , Transtorno Depressivo Maior/sangue , Transtorno Depressivo Maior/imunologia , Feminino , Humanos , Interleucina-10/sangue , Interleucina-1beta/sangue , Masculino , Fator de Necrose Tumoral alfa/sangue , Adulto Jovem
6.
Biometals ; 30(6): 861-872, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28993928

RESUMO

The zinc fingers proteins (ZNF) are the largest family of DNA binding proteins and can act as transcriptional factors in eukaryotes. ZNF are implicated in activation in response to environmental stimulus by biometals such as Zn2+. Many of these proteins have the classical C2H2 zinc finger motifs (C2H2-ZNFm) of approximately 30 amino acids, where a Zn2+ ion is coordinated by two cysteine and two histidine residues. Trichomonas vaginalis is a protozoan parasite than responds to environmental changes including Zn2+. Until now has not been described any ZNF that could be involved in the regulation of genic expression of T. vaginalis. Here, we characterized in silico and experimentally an annoted ZNF (TvZNF1) from T. vaginalis and isolated the gene, tvznf1 encoding it. TvZNF1 have eight C2H2-ZNFm with residues that maybe involved in the structural stability of DNA binding motifs. In this work we confirmed the Zn2+ upregulation expression of tvznf1 gene. Recombinant TvZNF1 was able to bind to specific DNA sequences according to EMSA assay. Additionally, we demonstrated that recombinant TvZNF1 bind to MRE signature in vitro, which strongly suggests its role in transcriptional regulation, similar to the one observed for mammalian MTF-1. This result suggested a conserved mechanism of genic regulation mediated by ZNFs in T. vaginalis.


Assuntos
Dedos de Zinco CYS2-HIS2 , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo , Trichomonas vaginalis/genética , Sítios de Ligação , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica , Estrutura Secundária de Proteína , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Elementos de Resposta , Fatores de Transcrição/genética , Trichomonas vaginalis/química , Trichomonas vaginalis/metabolismo , Zinco/metabolismo
7.
J Neuroimmunol ; 290: 22-5, 2016 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-26711564

RESUMO

Fibromyalgia (FM) is a chronic disease that has been linked to inflammatory reactions and changes in the systemic levels of proinflammatory cytokines that modulate responses in the sympathetic nervous system and hypothalamic-pituitary-adrenal axis. We found that concentrations of IL-6 and IL-8 were elevated in FM patients. Both cytokines correlated with clinical scores, suggesting that IL-6 and IL-8 have additive or synergistic effects in perpetuating the chronic pain in FM patients. These findings indicate that IL-6 and IL-8 are two of the most constant inflammatory mediators in FM and that their levels correlate significantly with the severity of symptoms.


Assuntos
Fibromialgia/sangue , Fibromialgia/diagnóstico , Mediadores da Inflamação/sangue , Interleucina-6/sangue , Interleucina-8/sangue , Adulto , Biomarcadores/sangue , Feminino , Humanos , Inflamação/sangue , Inflamação/diagnóstico , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários
8.
J Immunol Res ; 2015: 354957, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25961058

RESUMO

Serotonin (5-HT) induces concentration-dependent metabolic effects in diverse cell types, including neurons, entherochromaffin cells, adipocytes, pancreatic beta-cells, fibroblasts, smooth muscle cells, epithelial cells, and leukocytes. Three classes of genes regulating 5-HT function are constitutively expressed or induced in these cells: (a) membrane proteins that regulate the response to 5-HT, such as SERT, 5HTR-GPCR, and the 5HT3-ion channels; (b) downstream signaling transduction proteins; and (c) enzymes controlling 5-HT metabolism, such as IDO and MAO, which can generate biologically active catabolites, including melatonin, kynurenines, and kynurenamines. This review covers the clinical and experimental mechanisms involved in 5-HT-induced immunomodulation. These mechanisms are cell-specific and depend on the expression of serotonergic components in immune cells. Consequently, 5-HT can modulate several immunological events, such as chemotaxis, leukocyte activation, proliferation, cytokine secretion, anergy, and apoptosis. The effects of 5-HT on immune cells may be relevant in the clinical outcome of pathologies with an inflammatory component. Major depression, fibromyalgia, Alzheimer disease, psoriasis, arthritis, allergies, and asthma are all associated with changes in the serotonergic system associated with leukocytes. Thus, pharmacological regulation of the serotonergic system may modulate immune function and provide therapeutic alternatives for these diseases.


Assuntos
Imunomodulação/imunologia , Leucócitos/imunologia , Receptores de Serotonina/imunologia , Serotonina/imunologia , Animais , Artrite/imunologia , Asma/imunologia , Proteínas de Transporte de Cátions/genética , Proteínas de Transporte de Cátions/metabolismo , Quimiotaxia de Leucócito/imunologia , Humanos , Camundongos , Neoplasias/imunologia , Transporte Proteico/genética , Receptores de Serotonina/metabolismo , Serotonina/metabolismo , Transdução de Sinais/imunologia
9.
J Immunol Res ; 2015: 401630, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25961060

RESUMO

The benefits of garlic to health have been proclaimed for centuries; however, only recently have Allium sativum and its derivatives been proposed as promising candidates for maintaining the homeostasis of the immune system. The complex biochemistry of garlic makes it possible for variations in processing to yield different preparations with differences in final composition and compound proportion. In this review, we assess the most recent experimental results, which indicate that garlic appears to enhance the functioning of the immune system by stimulating certain cell types, such as macrophages, lymphocytes, natural killer (NK) cells, dendritic cells, and eosinophils, by mechanisms including modulation of cytokine secretion, immunoglobulin production, phagocytosis, and macrophage activation. Finally, because immune dysfunction plays an important role in the development and progress of several diseases, we critically examined immunoregulation by garlic extracts and compounds isolated, which can contribute to the treatment and prevention of pathologies such as obesity, metabolic syndrome, cardiovascular disorders, gastric ulcer, and even cancer. We concluded that A. sativum modulates cytokine secretion and that such modulation may provide a mechanism of action for many of their therapeutic effects.


Assuntos
Alho/metabolismo , Imunomodulação/efeitos dos fármacos , Inflamação/tratamento farmacológico , Extratos Vegetais/farmacologia , Citocinas/metabolismo , Células Dendríticas/efeitos dos fármacos , Células Dendríticas/imunologia , Eosinófilos/efeitos dos fármacos , Eosinófilos/imunologia , Humanos , Inflamação/imunologia , Células Matadoras Naturais/efeitos dos fármacos , Células Matadoras Naturais/imunologia , Ativação de Macrófagos/efeitos dos fármacos , Ativação de Macrófagos/imunologia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Fagocitose/efeitos dos fármacos , Fagocitose/imunologia
10.
Insect Biochem Mol Biol ; 41(6): 400-9, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21396445

RESUMO

Triosephosphate isomerase (TIM) is an enzyme with a role in glycolysis and gluconeogenesis by catalyzing the interconversion between glyceraldehyde 3-phosphate and dihydroxyacetone phosphate. This enzyme has been used as a target in endoparasite drug development. In this work we cloned, expressed, purified and studied kinetic and structural characteristics of TIM from tick embryos, Rhipicephalus (Boophilus) microplus (BmTIM). The Km and Vmax of the recombinant BmTIM with glyceraldehyde 3-phosphate as substrate, were 0.47 mM and 6031 µmol min⁻¹ mg protein⁻¹, respectively. The resolution of the diffracted crystal was estimated to be 2.4 Å and the overall data showed that BmTIM is similar to other reported dimeric TIMs. However, we found that, in comparison to other TIMs, BmTIM has the highest content of cysteine residues (nine cysteine residues per monomer). Only two cysteines could make disulfide bonds in monomers of BmTIM. Furthermore, BmTIM was highly sensitive to the action of the thiol reagents dithionitrobenzoic acid and methyl methane thiosulfonate, suggesting that there are five cysteines exposed in each dimer and that these residues could be employed in the development of species-specific inhibitors.


Assuntos
Embrião não Mamífero/enzimologia , Proteínas Recombinantes/metabolismo , Rhipicephalus/enzimologia , Triose-Fosfato Isomerase/metabolismo , Zigoto/enzimologia , Sequência de Aminoácidos , Animais , Catálise , Clonagem Molecular , Cristalografia por Raios X , Cisteína/química , Cisteína/metabolismo , Fosfato de Di-Hidroxiacetona/metabolismo , Dimerização , Escherichia coli , Gliceraldeído 3-Fosfato/metabolismo , Humanos , Cinética , Modelos Moleculares , Dados de Sequência Molecular , Conformação Proteica/efeitos dos fármacos , Proteínas Recombinantes/genética , Rhipicephalus/embriologia , Alinhamento de Sequência , Reagentes de Sulfidrila/farmacologia , Triose-Fosfato Isomerase/antagonistas & inibidores , Triose-Fosfato Isomerase/genética , Triose-Fosfato Isomerase/isolamento & purificação
11.
J Bioenerg Biomembr ; 40(4): 359-69, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18770013

RESUMO

We studied for the first time the ATP-synthase complex from shrimp as a model to understand the basis of crustacean bioenergetics since they are exposed to endogenous processes as molting that demand high amount of energy. We analyzed the cDNA sequence of two subunits of the Fo sector from mitochondrial ATP-synthase in the white shrimp Litopenaeus vannamei. The nucleus encoded atp9 subunit presents a 773 bp sequence, containing a signal peptide sequence only observed in crustaceans, and the mitochondrial encoded atp6 subunit presents a sequence of 675 bp, and exhibits high identity with homologous sequences from invertebrate species. ATP9 and ATP6 protein structural models interaction suggest specific functional characteristics from both proteins in the mitochondrial enzyme. Differences in the steady-state mRNA levels of atp9 and atp6 from five different tissues correlate with tissue function. Moreover, significant changes in the mRNA levels of both subunits at different molt stages were detected. We discussed some insights about the enzyme structure and the regulation mechanisms from both ATP-synthase subunits related to the energy requirements of shrimp.


Assuntos
Núcleo Celular/enzimologia , Mitocôndrias/enzimologia , Modelos Químicos , Modelos Moleculares , Penaeidae/enzimologia , ATPases Translocadoras de Prótons , Sequência de Aminoácidos , Animais , Sequência de Bases , Simulação por Computador , Perfilação da Expressão Gênica , Dados de Sequência Molecular , Conformação Proteica , Subunidades Proteicas , ATPases Translocadoras de Prótons/química , ATPases Translocadoras de Prótons/genética , ATPases Translocadoras de Prótons/ultraestrutura , RNA Mensageiro/genética
12.
J Mol Biol ; 342(3): 971-85, 2004 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-15342250

RESUMO

Catalase-1, one of four catalase activities of Neurospora crassa, is associated with non-growing cells and accumulates in asexual spores. It is a large, tetrameric, highly efficient, and durable enzyme that is active even at molar concentrations of hydrogen peroxide. Catalase-1 is oxidized at the heme by singlet oxygen without significant effects on enzyme activity. Here we present the crystal structure of catalase-1 at 1.75A resolution. Compared to structures of other catalases of the large class, the main differences were found at the carboxy-terminal domain. The heme group is rotated 180 degrees around the alpha-gamma-meso carbon axis with respect to clade 3 small catalases. There is no co-ordination bond of the ferric ion at the heme distal side in catalase-1. The catalase-1 structure exhibited partial oxidation of heme b to heme d. Singlet oxygen, produced catalytically or by photosensitization, may hydroxylate C5 and C6 of pyrrole ring III with a subsequent formation of a gamma-spirolactone in C6. The modification site in catalases depends on the way dioxygen exits the protein: mainly through the central channel or the main channel in large and small catalases, respectively. The catalase-1 structure revealed an unusual covalent bond between a cysteine sulphur atom and the essential tyrosine residue of the proximal side of the active site. A peptide with the predicted theoretical mass of the two bound tryptic peptides was detected by mass spectrometry. A mechanism for the Cys-Tyr covalent bond formation is proposed. The tyrosine bound to the cysteine residue would be less prone to donate electrons to compound I to form compound II, explaining catalase-1 resistance to substrate inhibition and inactivation. An apparent constriction of the main channel at Ser198 lead us to propose a gate that opens the narrow part of the channel when there is sufficient hydrogen peroxide in the small cavity before the gate. This mechanism would explain the increase in catalytic velocity as the hydrogen peroxide concentration rises.


Assuntos
Catalase/química , Sequência de Aminoácidos , Catalase/antagonistas & inibidores , Catalase/genética , Domínio Catalítico , Cristalografia por Raios X , Inibidores Enzimáticos/farmacologia , Heme/química , Peróxido de Hidrogênio/farmacologia , Modelos Moleculares , Dados de Sequência Molecular , Neurospora crassa/enzimologia , Neurospora crassa/genética , Oxirredução , Estrutura Quaternária de Proteína , Estrutura Secundária de Proteína , Oxigênio Singlete/química , Eletricidade Estática
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