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1.
Clin Chem Lab Med ; 58(1): 11-17, 2019 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-31421036

RESUMO

The appropriate identification of bacterial infection is the basis for effective treatment and control of infective disease. Among this context, an emerging biomarker of infection is presepsin (PSP), recently described as early marker of different infections. PSP secretion has been shown to be associated with monocyte phagocytosis and plasmatic levels of PSP increase in response to bacterial infection and decrease after antibiotic treatment, therefore it can be considered a marker of activation of immune cell response towards an invading pathogen. Different methods have been developed to measure PSP and this review will briefly describe the different clinical fields of application of PSP, ranging from intensive care to neonatal infection, to orthopedic and pulmonary infection as well as fungal infections and cardiovascular infections.


Assuntos
Infecções/diagnóstico , Infecções/metabolismo , Receptores de Lipopolissacarídeos/metabolismo , Fragmentos de Peptídeos/metabolismo , Biomarcadores/metabolismo , Cuidados Críticos , Serviço Hospitalar de Emergência , Humanos
2.
J Clin Densitom ; 22(1): 86-95, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30072203

RESUMO

Aseptic loosening is a major cause of premature failure of total knee replacement (TKR). Variations in periprosthetic bone mineral density (BMD) and osteoimmunological biomarkers levels could help to quantify prosthesis osteointegration and predict early aseptic loosening. The gene expression of 5 selected osteoimmunological biomarkers was evaluated in tibial plateau bone biopsies by real-time polymerase chain reaction and changes in their serum levels after TKR were prospectively evaluated with enzyme-linked immunosorbent assay for 1 yr after surgery. These variations were correlated to changes in periprosthetic BMD. Sixteen patients were evaluated. A statistically significant decrease in serum levels of Sclerostin (p = 0.0135) was observed immediately after surgery. A specular pattern was observed between dickkopf-related protein 1 and osteoprotegerin expression. No statistically significant changes were detectable in the other study biomarkers. Periprosthetic BMD did not change significantly across the duration of the follow-up. Prosthetic knee surgery has an impact on bone remodeling, in particular on sclerostin expression. Although not showing statistically significant changes, in the patterns of dickkopf-related protein 1, osteoprotegerin, and the ligand of the receptor activator of nuclear factor kappa-B symmetries and correspondences related to the biological activities of these proteins could be identified. Variation in osteoimmunological biomarkers after TKR surgery can help in quantifying prosthesis osteointegration.


Assuntos
Artroplastia do Joelho/efeitos adversos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Osteoprotegerina/genética , Falha de Prótese , Ligante RANK/genética , Proteínas Adaptadoras de Transdução de Sinal/sangue , Proteínas Adaptadoras de Transdução de Sinal/genética , Idoso , Biomarcadores/metabolismo , Densidade Óssea , Feminino , Fêmur/metabolismo , Expressão Gênica , Humanos , Interleucina-6/genética , Prótese do Joelho , Masculino , Pessoa de Meia-Idade , Osseointegração , Estudos Prospectivos , RNA Mensageiro/metabolismo , Receptor Ativador de Fator Nuclear kappa-B/genética , Tíbia/metabolismo
3.
Immun Ageing ; 16: 7, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30984280

RESUMO

In the brain, Oxidative Stress (OS) contribute to structural and functional changes associated with vascular aging, such as endothelial dysfunction, extracellular matrix degradation, resulting in age-related reduced vasodilatation in response to agonists. For this reason, OS is considered a key factor in Alzheimer's Disease (AD) development and recent evidence correlated oxidative stress with vascular lesion in the pathogenesis of AD, but the mechanism still need to be fully clarified. The etiology of AD is still not completely understood and is influenced by several factors including Apolipoprotein E (ApoE) genotype. In particular, the Apo ε4 isoform is considered a risk factor for AD development. This study was aimed to evaluate the possible relationship between three plasmatic OS marker and Apo ε4 carrier status. Plasmatic soluble receptor for advanced glycation end products (sRAGE) levels, plasma antioxidant total defenses (by lag-time method) and plasmatic Reactive Oxygen species (ROS) levels were evaluated in 25 AD patients and in 30 matched controls. ROS were significantly higher while plasma antioxidant total defenses and sRAGE levels were significantly lower in AD patients compared to controls. In AD patients lag-time values show a significant positive linear correlation with sRAGE levels and a (even not significant) negative correlation with ROS levels. Lag-time is significantly lower in ε4 carrier (N = 13) than in ε4 non-carrier (N = 12). Our result confirms the substantial OS in AD. Lag-time levels showed a significant positive correlation with sRAGE levels and a significant association with ε4 carrier status suggesting that plasmatic lag-time evaluation can be considered as a potential useful OS risk marker in AD.

4.
Aging Male ; 21(3): 200-205, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29327639

RESUMO

Erectile dysfunction is a common disease characterized by endothelial dysfunction. The aetiology of ED is often multifactorial but evidence is being accumulated in favor of the proper function of the vascular endothelium that is essential to achieving and maintaining penile erection. Uric acid itself causes endothelial dysfunction via decreased nitric oxide production. This study aims to evaluate the serum uric acid (SUA) levels in 180 ED patients, diagnosed with the International Index of Erectile Function-5 (IIEF-5) and 30 non-ED control. Serum uric acid was analyzed with a commercially available kit using ModularEVO (Roche, Monza, Italy). Within-assay and between-assay variations were 3.0% and 6.0%, respectively. Out of the ED patients, 85 were classified as arteriogenic (A-ED) and 95 as non-arteriogenic (NA-ED) with penile-echo-color-Doppler. Uric acid levels (median and range in mg/dL) in A-ED patients (5.8, 4.3-7.5) were significantly higher (p < .001) than in NA-ED patients (4.4, 2.6-5.9) and in control group (4.6, 3.1-7.2). There was a significant difference (p < .001) between uric acid levels in patients with mild A-ED (IIEF-5 16-20) and severe/complete A-ED (IIEF-5 ≤ 10) that were 5.4 (range 4.3-6.5) mg/dL and 6.8 (range 6.4-7.2) mg/dL, respectively. There was no difference between the levels of uric acid in patients with different degree of NA-ED. Our findings reveal that SUA is a marker of ED but only of ED of arteriogenic aetiology.


Assuntos
Impotência Vasculogênica/sangue , Ácido Úrico/sangue , Adulto , Estudos de Casos e Controles , Endotélio Vascular/fisiopatologia , Humanos , Impotência Vasculogênica/diagnóstico , Impotência Vasculogênica/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Ereção Peniana/fisiologia , Inquéritos e Questionários , Ultrassonografia Doppler em Cores
5.
Org Biomol Chem ; 16(28): 5167-5177, 2018 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-29971290

RESUMO

Glyoxalase II (GlxII) is an antioxidant glutathione-dependent enzyme, which catalyzes the hydrolysis of S-d-lactoylglutathione to form d-lactic acid and glutathione (GSH). The last product is the most important thiol reducing agent present in all eukaryotic cells that have mitochondria and chloroplasts. It is generally known that GSH plays a crucial role not only in the cellular redox state but also in various cellular processes. One of them is protein S-glutathionylation, a process that can occur through an oxidation reaction of proteins' thiol groups by GSH. Changes in protein S-glutathionylation have been associated with a range of human diseases such as diabetes, cardiovascular and pulmonary diseases, neurodegenerative diseases and cancer. Within a major project aimed at elucidating the role of GlxII in the mechanism of S-glutathionylation, a reliable computational protocol consisting of a protein-protein docking approach followed by atomistic Molecular Dynamics (MD) simulations was developed and it was applied to the prediction of molecular associations between human GlxII (in the presence and absence of GSH) and some proteins that are known to be S-glutathionylated in vitro, such as actin, malate dehydrogenase (MDH) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH). The computational results show a high propensity of GlxII to interact with actin and MDH through its active site and a high stability of the GlxII-protein systems when GSH is present. Moreover, close proximities of GSH with actin and MDH cysteine residues have been found, suggesting that GlxII could be able to perform protein S-glutathionylation by using the GSH molecule present in its catalytic site.


Assuntos
Simulação de Acoplamento Molecular , Tioléster Hidrolases/metabolismo , Actinas/metabolismo , Glutationa/metabolismo , Humanos , Simulação de Dinâmica Molecular , Ligação Proteica , Conformação Proteica , Termodinâmica , Tioléster Hidrolases/química
6.
Molecules ; 23(2)2018 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-29462955

RESUMO

As a part of research project aimed to optimize antioxidant delivery, here we studied the influence of both salts and lipid matrix composition on the interaction of epigallocatechin-3-gallate (EGCG) with bilayer leaflets. Thus, we combined in silico and experimental methods to study the ability of neutral and anionic vesicles to encapsulate EGCG in the presence of Ca2+ and Mg2+ divalent salts. Experimental and in silico results show a very high correlation, thus confirming the efficiency of the developed methodology. In particular, we found out that the presence of calcium ions hinders the insertion of EGCG in the liposome bilayer in both neutral and anionic systems. On the contrary, the presence of MgCl2 improves the insertion degree of EGCG molecules respect to the liposomes without divalent salts. The best and most efficient salt concentration is that corresponding to a 5:1 molar ratio between Mg2+ and EGCG, in both neutral and anionic vesicles. Concerning the lipid matrix composition, the anionic one results in better promotion of the catechin insertion within the bilayer since experimentally we achieved 100% EGCG encapsulation in the lipid carrier in the presence of a 5:1 molar ratio of magnesium. Thus, the combination of this anionic liposomal formulation with magnesium chloride, avoids time-consuming separation steps of unentrapped active principle and appears particularly suitable for EGCG delivery applications.


Assuntos
Antioxidantes/farmacologia , Catequina/análogos & derivados , Sistemas de Liberação de Medicamentos , Lipossomos/farmacologia , Antioxidantes/química , Cálcio/química , Catequina/química , Catequina/farmacologia , Bicamadas Lipídicas/química , Bicamadas Lipídicas/farmacologia , Lipídeos/química , Lipossomos/química , Magnésio/química , Tamanho da Partícula
7.
J Cell Biochem ; 117(8): 1833-42, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26728070

RESUMO

Skeletal muscle atrophy is a well-known adverse effect of chronic treatment with glucocorticoids and it also occurs when stress conditions such as sepsis and cachexia increase the release of endogenous glucocorticoids. Although the mechanisms of action of these hormones have been elucidated, the possible molecular mechanisms causing atrophy are not yet fully understood. The involvement of the O-GlcNAcylation process has recently been reported in disuse atrophy. O-GlcNAcylation, a regulatory post-translational modification of nuclear and cytoplasmic proteins consists in the attachment of O-GlcNAc residues on cell proteins and is regulated by two enzymes: O-GlcNAc-transferase (OGT) and O-GlcNAcase (OGA). O-GlcNAcylation plays a crucial role in many cellular processes and it seems to be related to skeletal muscle physiological function. The aim of this study is to investigate the involvement of O-GlcNAcylation in glucocorticoid-induced atrophy by using an "in vitro" model, achieved by treatment of C2C12 with 10 µM dexamethasone for 48 h. In atrophic condition, we observed that O-GlcNAc levels in cell proteins increased and concomitantly protein phosphorylation on serine and threonine residues decreased. Analysis of OGA expression at mRNA and protein levels showed a reduction in this enzyme in atrophic myotubes, whereas no significant changes of OGT expression were found. Furthermore, inhibition of OGA activity by Thiamet G induced atrophy marker expression. Our current findings suggest that O-GlcNAcylation is involved in dexamethasone-induced atrophy. In particular, we propose that the decrease in OGA content causes an excessive and mostly durable level of O-GlcNAc residues on sarcomeric proteins that might modify their function and stability. J. Cell. Biochem. 117: 1833-1842, 2016. © 2016 Wiley Periodicals, Inc.


Assuntos
Acetilglucosamina/metabolismo , Dexametasona/efeitos adversos , Proteínas Musculares/metabolismo , Atrofia Muscular/induzido quimicamente , Atrofia Muscular/metabolismo , N-Acetilglucosaminiltransferases/metabolismo , Acilação/efeitos dos fármacos , Animais , Linhagem Celular , Dexametasona/farmacologia , Camundongos
8.
Cell Biochem Funct ; 34(8): 620-627, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27935136

RESUMO

Glyoxalase II, the second of 2 enzymes in the glyoxalase system, is a hydroxyacylglutathione hydrolase that catalyses the hydrolysis of S-d-lactoylglutathione to form d-lactic acid and glutathione, which is released from the active site. The tripeptide glutathione is the major sulfhydryl antioxidant and has been shown to control several functions, including S-glutathionylation of proteins. S-Glutathionylation is a way for the cells to store reduced glutathione during oxidative stress, or to protect protein thiol groups from irreversible oxidation, and few enzymes involved in protein S-glutathionylation have been found to date. In this work, the enzyme glyoxalase II and its substrate S-d-lactoylglutathione were incubated with malate dehydrogenase or with actin, resulting in a glutathionylation reaction. Glyoxalase II was also submitted to docking studies. Computational data presented a high propensity of the enzyme to interact with malate dehydrogenase or actin through its catalytic site and further in silico investigation showed a high folding stability of glyoxalase II toward its own reaction product glutathione both protonated and unprotonated. This study suggests that glyoxalase II, through a specific interaction of its catalytic site with target proteins, could be able to perform a rapid and specific protein S-glutathionylation using its natural substrate S-d-lactoylglutathione. SIGNIFICANCE: This article reports for the first time a possible additional role of Glo2 that, after interacting with a target protein, is able to promote S-glutathionylation using its natural substrate SLG, a glutathione derived compound. In this perspective, Glo2 can play a new important regulatory role inS-glutathionylation, acquiring further significance in cellular post-translational modifications of proteins.


Assuntos
Simulação por Computador , Glutationa/metabolismo , Tioléster Hidrolases/metabolismo , Actinas/metabolismo , Glutationa/química , Humanos , Malato Desidrogenase/metabolismo , Simulação de Acoplamento Molecular , Tioléster Hidrolases/química
9.
J Cell Biochem ; 114(1): 204-11, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22903576

RESUMO

The sialylation level of molecules, sialoglycoproteins and gangliosides, protruding from plasma membranes regulates multiple facets of erythrocyte function, from interaction with endothelium to cell lifespan. Our results demonstrate that: (a) Both sialidases NEU1 and NEU3 are present on erythrocyte plasma membrane; (b) NEU1 is kept on the plasma membrane in absence of the protective protein/cathepsin A (PPCA); (c) NEU1 and NEU3 are retained on the plasma membrane, as peripheral proteins, associated to the external leaflet and released by alkaline treatments; (d) NEU1 and NEU3 are segregated in Triton X-100 detergent-resistant membrane domains (DRMs); (e) NEU3 shows activity also at neutral pH; and (f) NEU1 and NEU3 are progressively lost during erythrocyte life. Interestingly, sialidase activity released from erythrocyte membranes after an alkaline treatment preserves its functionality and recognizes sialoglycoproteins and gangliosides. On the other hand, the weak anchorage of sialidases to the plasma membrane and their loss during erythrocyte life could be a tool to preserve the cellular sialic acid content in order to avoid the early ageing of erythrocyte and processes of cell aggregation in the capillaries.


Assuntos
Membrana Celular/enzimologia , Citosol/enzimologia , Eritrócitos/enzimologia , Lisossomos/enzimologia , Neuraminidase/metabolismo , Western Blotting , Fracionamento Celular , Membrana Celular/química , Senescência Celular/fisiologia , Citosol/química , Eritrócitos/química , Gangliosídeos/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Lisossomos/química , Octoxinol/química , Ácidos Siálicos/metabolismo
10.
Antioxidants (Basel) ; 11(9)2022 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-36139840

RESUMO

Molecular biomarkers consent to apply individual decisions in the complex management of both acute or chronic diseases, and their identification constitutes a fundamental phase for achieving the important object to develop personalized therapies [...].

11.
Antioxidants (Basel) ; 11(6)2022 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-35739958

RESUMO

Bone is a very dynamic tissue, subject to continuous renewal to maintain homeostasis through bone remodeling, a process promoted by two cell types: osteoblasts, of mesenchymal derivation, are responsible for the deposition of new material, and osteoclasts, which are hematopoietic cells, responsible for bone resorption. Osteomyelitis (OM) is an invasive infectious process, with several etiological agents, the most common being Staphylococcus aureus, affecting bone or bone marrow, and severely impairing bone homeostasis, resulting in osteolysis. One of the characteristic features of OM is a strong state of oxidative stress (OS) with severe consequences on the delicate balance between osteoblastogenesis and osteoclastogenesis. Here we describe this, analyzing the effects of OS in bone remodeling and discussing the need for new, easy-to-measure and widely available OS biomarkers that will provide valid support in the management of the disease.

12.
Biomolecules ; 12(6)2022 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-35740951

RESUMO

Since no definitive cure for COVID-19 is available so far, one of the challenges against the disease is understanding the clinical features and the laboratory inflammatory markers that can differentiate among different severity grades of the disease. The aim of the present study is a comprehensive and longitudinal evaluation of SCD14-ST and other new inflammatory markers, as well as cytokine storm molecules and current inflammatory parameters, in order to define a panel of biomarkers that could be useful for a better prognostic prediction of COVID-19 mortality. SCD14-ST, as well as the inflammatory markers IL-6, IL-10, SuPAR and sRAGE, were measured in plasma-EDTA of ICU COVID-19 positive patients. In this longitudinal study, SCD14-ST resulted significantly higher in patients who eventually died compared to those who were discharged from the ICU. The results suggest that the new infection biomarker SCD14-ST, in addition to new generation inflammatory biomarkers, such as SuPAR, sRAGE and the cytokines IL-6 and IL-10, can be a useful prognostic tool associated with canonical inflammatory parameters, such as CRP, to predict SARS-CoV-2 outcome in ICU patients.


Assuntos
COVID-19 , Receptores de Lipopolissacarídeos , Biomarcadores , COVID-19/diagnóstico , Humanos , Interleucina-10 , Interleucina-6 , Estudos Longitudinais , Receptores de Ativador de Plasminogênio Tipo Uroquinase , SARS-CoV-2
13.
J Clin Med ; 10(20)2021 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-34682915

RESUMO

Glycation and glycosylation are non-enzymatic and enzymatic reactions, respectively, of glucose, glucose metabolites, and other reducing sugars with different substrates, such as proteins, lipids, and nucleic acids. Increased availability of glucose is a recognized risk factor for the onset and progression of diabetes-mellitus-associated disorders, among which cardiovascular diseases have a great impact on patient mortality. Both advanced glycation end products, the result of non-enzymatic glycation of substrates, and O-linked-N-Acetylglucosaminylation, a glycosylation reaction that is controlled by O-N-AcetylGlucosamine (GlcNAc) transferase (OGT) and O-GlcNAcase (OGA), have been shown to play a role in cardiovascular remodeling. In this review, we aim (1) to summarize the most recent data regarding the role of glycation and O-linked-N-Acetylglucosaminylation as glucose-related pathogenetic factors and disease markers in cardiovascular remodeling, and (2) to discuss potential common mechanisms linking these pathways to the dysregulation and/or loss of function of different biomolecules involved in this field.

14.
Clin Chem Lab Med ; 48(2): 213-6, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20001851

RESUMO

BACKGROUND: Italian air force acrobatic pilots are occupationally susceptible to oxidative stress damage that can lead to overt signs and symptoms of hypoxia. We propose erythrocyte glycohydrolases as new, sensitive markers to assess oxidative stress. METHODS: We measured erythrocyte concentrations of beta-D-glucuronidase (GCR), hexosaminidase, O-beta-N-acetyl-D-glucosaminidase (O-GlcNAcase), plasma membrane fluidity and plasma hydroperoxides from 19 pilots and compared these to 40 matched healthy subjects. RESULTS: Plasma hydroperoxide concentrations and the erythrocyte ghosts' fluorescence anisotropy were significantly lower in the pilots. Concentrations of GCR, O-GlcNAcase and hexosaminidase in pilots were significantly different from controls, being lower, higher and higher, respectively. CONCLUSIONS: Pilots, in spite of their oxidative stress, are better protected than controls, probably as a result of their physical training and proper diet. Our results confirm that erythrocytes, with their 120-day life span, are a useful model for investigating physiopathological conditions, and glycohydrolases are good markers for monitoring oxidative stress, even in healthy people.


Assuntos
Acetilglucosaminidase/sangue , Aeronaves , Eritrócitos/enzimologia , Hexosaminidases/sangue , Peróxido de Hidrogênio/sangue , Militares , Exposição Ocupacional , Acetilglucosaminidase/metabolismo , Adulto , Biomarcadores/metabolismo , Estudos de Casos e Controles , Membrana Eritrocítica/enzimologia , Feminino , Polarização de Fluorescência , Hexosaminidases/metabolismo , Humanos , Peróxido de Hidrogênio/metabolismo , Masculino , Fluidez de Membrana , Pessoa de Meia-Idade , Estresse Oxidativo , Fatores de Tempo , Adulto Jovem
15.
Mech Ageing Dev ; 191: 111333, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32814082

RESUMO

Erythrocytes are deeply sensitive cells and important health indicators. During inflammatory response RBC, as a part of haematological system, are exposed to circulating inflammatory mediators and related oxidative stress. They present a highly specialized and organized cell membrane that interacts with inflammatory mediators and oxidative agents, leading to a variety of structural changes that promptly signal an abnormal situation. This review is aimed to provide an overview on erythrocyte involvement in physiological and pathological processes related to oxidative stress, such as aging, Down syndrome, neurodegenerative diseases, for instance Alzheimer Disease, erectile dysfunction and cardiovascular diseases. In particular this review will focus on the effects of oxidative stress on structural changes in the cell membrane and also on in the activity of erythrocyte enzymes such as membrane-bound, cytosolic glycohydrolases and RBC-eNOS. This review also underlines the potential clinical application of erythrocyte specific related parameters, which can be important tools not only for the study but also for the monitoring of several oxidative stress related diseases.


Assuntos
Doença de Alzheimer/sangue , Síndrome de Down/sangue , Disfunção Erétil/sangue , Membrana Eritrocítica/metabolismo , Estresse Oxidativo , Animais , Biomarcadores/sangue , Feminino , Humanos , Masculino
16.
Int J Biol Macromol ; 160: 1090-1100, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32485258

RESUMO

Serotonin (5-HT) receptors have been shown to homodimerize and heterodimerize with other G protein-coupled receptors (GPCRs), although the details of this process have not yet been elucidated. Here we use coarse-grained molecular dynamics on monomeric 5-HT2C receptors to predict the transmembrane (TM) helices involved in such associations. All these simulations were carried out both in 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) lipid bilayers and in mixed composition POPC-Cholesterol ones, to show whether the presence of cholesterol could directly influence and drive the dimeric association. The goal is to get insights on the self-assembly pathway leading to GPCRs 5-HT2C oligomerization, which is supposed to be the basis of its constitutional activity. From the analysis of the molecular dynamics trajectories, we observed the formation of 5-HT2C oligomers through self-assembly and we identified the main domains involved in the receptor dimerization. In particular, dimers and oligomers from the two different environments show TM4-TM5 and TM1-TM7-H8 as the preferential dimerization interfaces. Nevertheless, substantial differences arise for oligomers in POPC and in POPC-Chol membranes: in POPC-Chol the variability of dimers interfaces is strictly limited to the TM1-TM7-H8 and TM4-TM5 interfaces and the dimorphism depends on cholesterol that directly participates in its formation. These results are in agreement with both experimental evidences and other computational studies conducted on other GPCRs oligomerization.


Assuntos
Colesterol/química , Multimerização Proteica , Receptor 5-HT2C de Serotonina/química , Bicamadas Lipídicas/química , Simulação de Dinâmica Molecular , Fosfatidilcolinas/química , Domínios Proteicos , Receptor 5-HT2C de Serotonina/metabolismo
17.
J Leukoc Biol ; 108(2): 697-704, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32034807

RESUMO

Bone and the immune system are closely linked: bone regulates the hematopoietic stem cells, which are precursors of immune cells, and several immunoregulatory cytokines influence the differentiation of bone cells, thus defining the osteoimmunological system. Cytokines and growth factors produced by immune and bone cells promote tumors in bone, supporting the vicious cycle of bone metastasis. Therefore osteoimmunological molecules linking the immune and bone systems could have diagnostic and prognostic potential for bone metastases. The osteoimmunologic Wnt pathway has been recently described as an important pathway with a vital role in bone carcinogenesis and metastatic progression. We examined the Wnt inhibitor DKK-1, sclerostin and several other osteoimmunological biomarkers involved in bone metastatic progression: RANKL, OPG, OPN, matrix metalloproteinase MMP-3 and the Receptor of Advanced Glycosylated End-products sRAGE. OPN and sclerostin proved good biomarkers of metastatic bone progression; the RANKL/OPG ratio was a good indicator of bone erosion in the metastatic process, while sRAGE had a protective role against metastatic progression in bone. These results serve to define a panel of new osteoimmunological biomarkers that could be useful in assessing the progress of osteolytic bone metastases.


Assuntos
Biomarcadores/sangue , Neoplasias Ósseas/sangue , Neoplasias Ósseas/secundário , Fatores Imunológicos/sangue , Proteínas Wnt/antagonistas & inibidores , Idoso , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/patologia , Feminino , Humanos , Imunomodulação/efeitos dos fármacos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Osteólise , Curva ROC
18.
J Nephrol ; 22(5): 630-6, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19809996

RESUMO

BACKGROUND: Renal replacement therapies (RRTs) produce a partial loss of antioxidants and formation of reactive oxygen species (ROS), which are a major factor involved in alterations of plasma membrane fluidity and endothelial activation, but their role on plasma membrane fluidity in vivo is still unclear. We compared erythrocyte plasma membrane fluidity, ROS and total plasma antioxidant defenses (Lagtime) in aged patients with chronic renal failure (CRF) on conservative treatment, peritoneal dialysis (PD) and hemodialysis (HD) before (HD-pre) and after (HD-post) a treatment, to evaluate the role of different RRTs on oxidative stress and plasma membrane fluidity in aged patients. METHODS: We assessed erythrocyte plasma membrane fluidity, plasma lipid hydroperoxide levels and Lag-Time in 11 CRF patients on conservative treatment, 15 on PD, 12 on HD and 30 healthy controls. RESULTS: Hydroperoxides were higher in CRF, PD and HD-post, whereas Lag-time was significantly lower in PD, CRF and in HD-post. CRF, PD and HD-pre also had higher membrane fluidity (rsDPH), compared with HD-post and controls. CONCLUSION: These findings are in keeping with the hypothesis that the Lag-time decrease is due not only to the effect of the RRT but also to the uremic state, and that PD patients undergo a chronic, greater oxidative stress. Contrary to expectations, all patients showed greater erythrocyte membrane fluidity, which can be attributed to uremic toxicity. These observations reinforce the hypothesis that oxidative stress is an intrinsic component of this disease state and indeed is already present also in CRF not yet requiring RRT.


Assuntos
Membrana Eritrocítica/fisiologia , Falência Renal Crônica/fisiopatologia , Falência Renal Crônica/terapia , Fluidez de Membrana/fisiologia , Estresse Oxidativo/fisiologia , Terapia de Substituição Renal/métodos , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/metabolismo , Estudos de Casos e Controles , Feminino , Humanos , Peróxidos Lipídicos/sangue , Masculino , Diálise Peritoneal , Espécies Reativas de Oxigênio/metabolismo , Diálise Renal
19.
Artigo em Inglês | MEDLINE | ID: mdl-31001202

RESUMO

High Crosslink process was introduced in the development of joint prosthetic devices, in order to decrease the wear rate of ultrahigh molecular weight polyethylene (UHMWPE), but it also triggers the formation of free radicals and oxidative stress, which affects the physiological bone remodeling, leading to osteolysis. Vitamin E stabilization of UHMWPE was proposed to provide oxidation resistance without affecting mechanical properties and fatigue strength. The aim of this study is to evaluate the antioxidant effect of vitamin E added to UHMWPE on oxidative stress induced osteolysis, focusing in particular on the oxidative stress response in correlation with the production of osteoimmunological markers, Sclerostin and DKK-1, and the RANKL/OPG ratio compared to conventional UHMWPE wear debris. Human osteoblastic cell line SaOS2 were incubated for 96 h with wear particles derived from crosslinked and not crosslinked Vitamin E-stabilized, UHMWPE without Vitamin E, and growth medium as control. Cellular response to oxidative stress, compared to not treat cells, was evaluated in terms of proteins O-GlcNAcylation, cellular levels of OGA, and OGT proteins by immunoblotting. O-GlcNAcylation and its positive regulator OGT levels are increased in the presence of Vitamin E blended UHMWPE, in particular with not crosslinked Vit E stabilized UHMWPE. Conversely, the negative regulator OGA increased in the presence of UHMWPE not blended with Vitamin E. Vitamin E-stabilized UHMWPE induced a decrease of RANKL/OPG ratio compared to UHMWPE without Vitamin E, and the same effect was observed for Sclerostin, while DKK-1 was not significantly affected. In conclusion, Vitamin E stabilization of UHMWPE increased osteoblast response to oxidative stress, inducing a cellular mechanism aimed at cell survival. Vitamin E antioxidant effect influences the secretion of osteoimmunological factors, shifting the bone turnover balance toward bone protection stimuli. This suggests that Vitamin E-Stabilization of UHMWPE could contribute to reduction of oxidation-induced osteolysis and the consequent loosening of the prosthetic devices, therefore improving the longevity of total joint replacements.

20.
Exp Gerontol ; 124: 110629, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31175960

RESUMO

Permethrin is a synthetic pyrethroid extensively used as anti-woodworm agent and for indoor and outdoor pest control. The main route of human exposure is through fruit, vegetable and milk intake. Low dosage exposure to permethrin during neonatal brain development (from postnatal day 6 to postnatal day 21) leads to dopamine decrease in rat striatum nucleus, oxidative stress and behavioural changes linked to the development of Parkinson's like neurodegeneration later in life. The aim of this study was to evaluate the expression of genes involved in the dopaminergic pathway and epigenetic regulatory mechanisms in adolescent rats treated with permethrin during neonatal brain development. Furthermore, in order to shed light on the mechanisms associated with molecular impairments, in silico studies were performed. The outcomes show increased expression of genes related to the dopamine-synthesis pathway (Nurr1, Th, Snca), epigenetics (TET proteins and Mecp2) and exposure to toxicants (Pon1 and Pon2) in adolescent rats compared with control group. Furthermore, increased global 5mC and 5hmC levels were observed in the DNA extracted from striatum of early-life treated rats in comparison with controls. FAIRE-qPCR analysis shows that permethrin induces an enrichment of chromatin-free DNA at the level of Th and Nurr1 promoters, and ChIP-qPCR reveals a significant reduction in methylation levels at H3K9me3 position at both Th and Nurr1 promoter regions. In silico studies show that permethrin competes for the same two binding sites of known NURR1 agonists, with a lower binding free energy for permethrin, suggesting an important durable association of permethrin with the orphan receptor. Moreover, alpha-synuclein shows a strong affinity for NURR1, corroborating previous experimental outcomes on the interactions between them. This study focuses on an emerging role of early-life exposure to environmental pollutants in the regulation of late onset diseases through intriguing mechanisms that change crucial epigenetic patterns starting from adolescent age.


Assuntos
Corpo Estriado/efeitos dos fármacos , Dopamina/metabolismo , Epigênese Genética , Doenças Neurodegenerativas/genética , Membro 2 do Grupo A da Subfamília 4 de Receptores Nucleares/genética , Permetrina/toxicidade , Envelhecimento , Animais , Animais Recém-Nascidos , Corpo Estriado/patologia , Metilação de DNA , Metilases de Modificação do DNA/genética , Masculino , Simulação de Acoplamento Molecular , Doenças Neurodegenerativas/induzido quimicamente , Regiões Promotoras Genéticas , Multimerização Proteica , Ratos , Ratos Wistar , alfa-Sinucleína/metabolismo
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