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1.
Int J Mol Sci ; 25(13)2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-39000198

RESUMO

Breast cancer (BC) continues to pose a significant burden on global cancer-related morbidity and mortality, primarily driven by metastasis. However, the combined influence of microRNAs (miRNAs) and intratumoral microbiota on BC metastasis remains largely unexplored. In this study, we aimed to elucidate the interplay between intratumoral microbiota composition, miRNA expression profiles, and their collective influence on metastasis development in BC patients by employing 16S rRNA sequencing and qPCR methodologies. Our findings revealed an increase in the expression of miR-149-5p, miR-20b-5p, and miR-342-5p in metastatic breast cancer (Met-BC) patients. The Met-BC patients exhibited heightened microbial richness and diversity, primarily attributed to diverse pathogenic bacteria. Taxonomic analysis identified several pathogenic and pro-inflammatory species enriched in Met-BC, contrasting with non-metastatic breast cancer (NonMet-BC) patients, which displayed an enrichment in potential probiotic and anti-inflammatory species. Notably, we identified and verified a baseline prognostic signature for metastasis in BC patients, with its clinical relevance further validated by its impact on overall survival. In conclusion, the observed disparities in miRNA expression and species-level bacterial abundance suggest their involvement in BC progression. The development of a prognostic signature holds promise for metastasis risk assessment, paving the way for personalized interventions and improved clinical outcomes in BC patients.


Assuntos
Neoplasias da Mama , Progressão da Doença , MicroRNAs , Microbiota , Metástase Neoplásica , Humanos , MicroRNAs/genética , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Neoplasias da Mama/microbiologia , Feminino , Microbiota/genética , Pessoa de Meia-Idade , RNA Ribossômico 16S/genética , Regulação Neoplásica da Expressão Gênica , Prognóstico , Adulto , Idoso
2.
NPJ Breast Cancer ; 10(1): 36, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38750090

RESUMO

Early breast cancer patients often experience relapse due to residual disease after treatment. Liquid biopsy is a methodology capable of detecting tumor components in blood, but low concentrations at early stages pose challenges. To detect them, next-generation sequencing has promise but entails complex processes. Exploring larger blood volumes could overcome detection limitations. Herein, a total of 282 high-volume plasma and blood-cell samples were collected for dual ctDNA/CTCs detection using a single droplet-digital PCR assay per patient. ctDNA and/or CTCs were detected in 100% of pre-treatment samples. On the other hand, post-treatment positive samples exhibited a minimum variant allele frequency of 0.003% for ctDNA and minimum cell number of 0.069 CTCs/mL of blood, surpassing previous investigations. Accurate prediction of residual disease before surgery was achieved in patients without a complete pathological response. A model utilizing ctDNA dynamics achieved an area under the ROC curve of 0.92 for predicting response. We detected disease recurrence in blood in the three patients who experienced a relapse, anticipating clinical relapse by 34.61, 9.10, and 7.59 months. This methodology provides an easily implemented alternative for ultrasensitive residual disease detection in early breast cancer patients.

3.
Medicina (Kaunas) ; 59(4)2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-37109770

RESUMO

Background and Objectives: The global prevalence of chronic hepatitis C virus (HCV) infection is 0.8%, affecting around 58 million people worldwide. Treatment with DAAs reduces all-cause HCV mortality by 49-68%. This work aims to determine whether there is liver fibrosis regression (LFR) in patients who achieved Sustained Virological Response (SVR) after treatment with DAAs. Materials and Methods: An analytical, observational, single-center, and cohort study was carried out. The final sample consisted of 248 HCV-infected patients. All started treatment with DAAs between January 2015 and December 2017. Five measurements were performed to determine the fibrotic stage in patients (measured in kilopascals (kPa)) using transient elastography (FibroScan®, Echosens, The Netherlands). Results: Taking the baseline fibrotic stage as a reference, the distribution in subgroups was as follows: 77 F4 patients (31.0%); 55 F3 patients (22.2%); 53 F2 patients (21.4%); and 63 F0/F1 patients (25.4%). There were 40 patients (16.1%) with at least one HCV complication and 13 (5.2%) who developed hepatocellular carcinoma. The overall LFR rate was 77.8% (144 of 185 F2/F3/F4 patients, p = 0.01) at the end of the follow-up period. The highest mean FibroScan® values were observed in patients with: "male gender"; "metabolic syndrome"; "subtype 1a"; "NRP DAA"; "at least one HCV complication"; "death from HCV complications"; and "liver transplantation requirement". Conclusions: Treatment with DAAs achieved high rates of LFR and a decrease in mean FibroScan® values in all subgroups.


Assuntos
Hepatite C Crônica , Neoplasias Hepáticas , Humanos , Masculino , Antivirais/uso terapêutico , Estudos de Coortes , Hepatite C Crônica/complicações , Hepatite C Crônica/tratamento farmacológico , Cirrose Hepática/complicações , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/epidemiologia , Neoplasias Hepáticas/tratamento farmacológico
4.
Front Med (Lausanne) ; 7: 615312, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33344488

RESUMO

Background: Coronavirus disease 2019 (COVID-19), caused by Severe Acute Respiratory Syndrome-Corona Virus 2 has generated significant impact on global health worldwide. COVID-19 can cause pneumonia and organ injury. Chronic kidney disease (CKD) has been associated with increased mortality in previous epidemics, but there is a paucity of data regarding actual risks for non-dialysis CKD patients with COVID-19. Methods: Multicenter, observational cohort study including 136 non-dialysis CKD patients and 136 age- and sex-matched controls that required hospitalization due to COVID-19. Patients with end-stage renal disease, a kidney transplant or without registered baseline glomerular filtration rate prior to COVID-19 infection were excluded. CKD and acute kidney injury (AKI) were defined according to KDIGO criteria. Results: CKD patients had higher white blood cell count and D-dimer and lower lymphocyte percentage. No differences were found regarding symptoms on admission. CKD was associated with higher rate of AKI (61 vs. 24.3%) and mortality (40.4 vs. 24.3%). Patients with AKI had the highest hazard for death (AKI/non-CKD HR:7.04, 95% CI:2.87-17.29; AKI/CKD HR:5.25, 95% CI: 2.29-12.02), followed by CKD subjects without AKI (HR:3.39, 95% CI:1.36-8.46). CKD status did not condition ICU admission or length of in-hospital stay. Conclusions: CKD patients that require hospitalization due to COVID-19 are exposed to higher risk of death and AKI.

5.
Crit Care ; 24(1): 691, 2020 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-33317616

RESUMO

BACKGROUND: COVID-19 can course with respiratory and extrapulmonary disease. SARS-CoV-2 RNA is detected in respiratory samples but also in blood, stool and urine. Severe COVID-19 is characterized by a dysregulated host response to this virus. We studied whether viral RNAemia or viral RNA load in plasma is associated with severe COVID-19 and also to this dysregulated response. METHODS: A total of 250 patients with COVID-19 were recruited (50 outpatients, 100 hospitalized ward patients and 100 critically ill). Viral RNA detection and quantification in plasma was performed using droplet digital PCR, targeting the N1 and N2 regions of the SARS-CoV-2 nucleoprotein gene. The association between SARS-CoV-2 RNAemia and viral RNA load in plasma with severity was evaluated by multivariate logistic regression. Correlations between viral RNA load and biomarkers evidencing dysregulation of host response were evaluated by calculating the Spearman correlation coefficients. RESULTS: The frequency of viral RNAemia was higher in the critically ill patients (78%) compared to ward patients (27%) and outpatients (2%) (p < 0.001). Critical patients had higher viral RNA loads in plasma than non-critically ill patients, with non-survivors showing the highest values. When outpatients and ward patients were compared, viral RNAemia did not show significant associations in the multivariate analysis. In contrast, when ward patients were compared with ICU patients, both viral RNAemia and viral RNA load in plasma were associated with critical illness (OR [CI 95%], p): RNAemia (3.92 [1.183-12.968], 0.025), viral RNA load (N1) (1.962 [1.244-3.096], 0.004); viral RNA load (N2) (2.229 [1.382-3.595], 0.001). Viral RNA load in plasma correlated with higher levels of chemokines (CXCL10, CCL2), biomarkers indicative of a systemic inflammatory response (IL-6, CRP, ferritin), activation of NK cells (IL-15), endothelial dysfunction (VCAM-1, angiopoietin-2, ICAM-1), coagulation activation (D-Dimer and INR), tissue damage (LDH, GPT), neutrophil response (neutrophils counts, myeloperoxidase, GM-CSF) and immunodepression (PD-L1, IL-10, lymphopenia and monocytopenia). CONCLUSIONS: SARS-CoV-2 RNAemia and viral RNA load in plasma are associated with critical illness in COVID-19. Viral RNA load in plasma correlates with key signatures of dysregulated host responses, suggesting a major role of uncontrolled viral replication in the pathogenesis of this disease.


Assuntos
COVID-19/complicações , RNA Viral/análise , Carga Viral/imunologia , Adulto , Idoso , Biomarcadores/análise , Biomarcadores/sangue , COVID-19/sangue , Distribuição de Qui-Quadrado , Estado Terminal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Reação em Cadeia da Polimerase/métodos , RNA Viral/sangue , Estatísticas não Paramétricas
7.
Phys Chem Chem Phys ; 22(13): 6919-6927, 2020 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-32181454

RESUMO

The amino acid lysine has been shown to prevent water crystallization at low temperatures in saturated aqueous solutions [S. Cerveny and J. Swenson, Phys. Chem. Chem. Phys., 2014, 16, 22382-22390]. Here, we investigate two ratios of water and lysine (5.4 water molecules per lysine (saturated) and 11 water molecules per lysine) by means of the complementary use of computer simulations and neutron diffraction. By performing a detailed structural analysis we have been able to explain the anti-freeze properties of lysine by the strong hydrogen bond interactions of interstitial water molecules with lysine that prevent them from forming crystalline seeds. Additional water molecules beyond the 1 : 5.4 proportion are no longer tightly bonded to lysine and therefore are free to form crystals.


Assuntos
Simulação por Computador , Crioprotetores/química , Lisina/química , Modelos Moleculares , Difração de Nêutrons , Água/química , Cristalização , Ligação de Hidrogênio , Soluções/química
9.
Langmuir ; 35(32): 10601-10609, 2019 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-31335148

RESUMO

Gold nanoparticles (AuNPs) functionalized with proteins to impart desirable surface properties have been developed for many nanobiotechnology applications. A strong interaction between the protein and nanoparticle is critical to the formation of a stable conjugate to realize the potential of these emerging technologies. In this work, we examine the robustness of a protein layer adsorbed onto gold nanoparticles while under the stress of a physiological environment that could potentially lead to protein exchange on the nanoparticle surface. The adsorption interaction of common blood plasma proteins (transferrin, human serum albumin, and fibrinogen) and anti-horseradish peroxidase antibody onto AuNPs is investigated by nanoparticle tracking analysis. Our data show that a monolayer of protein is formed at saturation for each protein, and the maximum size increase for the conjugate, relative to the AuNP core, correlates with the protein size. The binding affinity of each protein to the AuNP is extracted from a best fit of the adsorption isotherm to the Hill equation. The antibody displays the greatest affinity (Kd = 15.2 ± 0.8 nM) that is ∼20-65 times stronger than the affinity of the other plasma proteins. Antibody-AuNP conjugates were prepared, purified, and suspended in solutions of blood plasma proteins to evaluate the stability of the antibody layer. An enzyme-mediated assay confirms that the antibody-AuNP interaction is irreversible, and the adsorbed antibody resists displacement by the plasma proteins. This work provides insight into the capabilities and potential limitations of antibody-AuNP-enabled technologies in biological systems.


Assuntos
Anticorpos/química , Proteínas Sanguíneas/química , Ouro/química , Nanopartículas Metálicas/química , Adsorção , Animais , Camundongos
10.
Bioconjug Chem ; 30(4): 1182-1191, 2019 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-30844256

RESUMO

Novel detection strategies that exploit the unique properties of gold nanoparticles (AuNPs) hold great promise for the advancement of diagnostic testing. Fundamental to many of these nanoparticle-enabled techniques is the immobilization of antibodies onto the AuNP surface to afford selective binding to target species. Orientation and loading density of the immobilized antibodies govern Fab accessibility and are critical to the analytical performance. Here, we use pH to systematically control the surface charge distribution on an antibody and investigate the impact of protein charge on adsorption to AuNPs. Nanoparticle tracking analysis (NTA) is used to measure the adsorption dynamics of anti-horseradish peroxidase antibody (anti-HRP) onto AuNPs at different pHs. NTA enables in situ measurement of antibody adsorption on AuNP by measuring the increase in hydrodynamic diameter ( DH) of the AuNPs as a function of antibody concentration. The adsorption affinity, protein layer thickness, and binding cooperativity at each pH are extracted from the best fit of the adsorption isotherms to the Hill-modified Langmuir equation. Our data show a monolayer of antibody is formed at saturation at pHs 7.5, 8.0, and 8.5, and no difference in anti-HRP-AuNP binding constants is observed in this pH range ( Kd ∼11 nM). However, the increase in DH of the AuNPs with adsorbed protein at monolayer coverage is pH-dependent, measuring 13.2 ± 1.1 nm, 9.8 ± 1.0 nm, and 7.4 ± 0.6 nm for pHs 7.5, 8.0, and 8.5, respectively. Moreover, results of an enzyme-mediated assay reveal the antigen-binding capacity of the immobilized anti-HRP antibody is 33 ± 2%, 23 ± 7%, and 18 ± 2% when adsorbed at pHs 7.5, 8.0, and 8.5, respectively. Our data confirm that antibody charge can be altered with pH to modulate and optimize antibody orientation on AuNP. These studies describe our continued efforts to establish design criteria to prepare conjugates with maximum antigen-binding activity that will enhance the performance of biofunctional nanomaterials.


Assuntos
Anticorpos/química , Ouro/química , Concentração de Íons de Hidrogênio , Nanopartículas Metálicas/química , Adsorção , Peroxidase do Rábano Silvestre/química
11.
Parasit Vectors ; 11(1): 434, 2018 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-30053904

RESUMO

BACKGROUND: Triatomine insects are vectors of Trypanosoma cruzi, the causal agent of Chagas disease. The insect-parasite interaction has been studied in relation to the transmission and prevalence of this disease. For most triatomines, however, several crucial aspects of the insect immune response are still unknown. For example, only for Rhodnius prolixus and Triatoma infestans has the activity of phenoloxidase (PO) and its zymogen prophenoloxidase (proPO) been reported in relation to the hemolymph and anterior midgut (AM). The aim of this study was to gain insight into the immune response to T. cruzi infection of an important triatomine in Mexico, Meccus pallidipennis. METHODS: Parasites were quantified in the rectal contents of infected M. pallidipennis groups. We examined some key factors in disease transmission, including the systemic (hemolymph) and local (gut) immune response. RESULTS: Parasites were present in the rectal contents at 4 days post-infection (pi) and reached their maximum density on day 7 pi. At 7 and 9 days pi mainly metacyclic trypomastigotes occurred. Compared to the control, the infected insects exhibited diminished PO activity in the hemolymph on days 9, 16 and 20 pi, and in the AM only on day 9. Additionally, infected insects displayed lower proPO activity in the hemolymph on day 1, but greater activity in the AM on day 28. CONCLUSIONS: The parasite strain originating from M. pallidipennis rapidly colonized the rectum of nymphs of this triatomine and developed high numbers of metacyclic trypomastigotes. Neither the changes of concentrations of PO and proPO in the hemolymph nor in the AM correlated with the changes in the population of T. cruzi.


Assuntos
Catecol Oxidase/metabolismo , Precursores Enzimáticos/metabolismo , Insetos Vetores/parasitologia , Monofenol Mono-Oxigenase/metabolismo , Reduviidae/enzimologia , Reduviidae/parasitologia , Trypanosoma cruzi/fisiologia , Animais , Catecol Oxidase/genética , Doença de Chagas/transmissão , Precursores Enzimáticos/genética , Regulação Enzimológica da Expressão Gênica , Interações Hospedeiro-Parasita , Humanos , Insetos Vetores/enzimologia , Camundongos , Monofenol Mono-Oxigenase/genética , Ninfa/enzimologia , Ninfa/parasitologia
12.
Phys Chem Chem Phys ; 20(9): 6401-6408, 2018 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-29442107

RESUMO

A DSC study of dilute glassy LiCl aqueous solutions in the water-dominated regime provides direct evidence of a glass-to-liquid transition in expanded high density amorphous (eHDA)-type solutions. Similarly, low density amorphous ice (LDA) exhibits a glass transition prior to crystallization to ice Ic. Both glass transition temperatures are independent of the salt concentration, whereas the magnitude of the heat capacity increase differs. By contrast to pure water, the glass transition endpoint for LDA can be accessed in LiCl aqueous solutions above 0.01 mole fraction. Furthermore, we also reveal the endpoint for HDA's glass transition, solving the question on the width of both glass transitions. This suggests that both equilibrated HDL and LDL can be accessed in dilute LiCl solutions, supporting the liquid-liquid transition scenario to understand water's anomalies.

13.
Mol Pharm ; 14(11): 3636-3643, 2017 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-28915351

RESUMO

With the aim of finding a correlation between the crystallization kinetics and the molecular dynamics of a substance that would allow prediction of its crystallization time as a function of temperature for a given α relaxation time, we have studied stiripentol, an anticonvulsant drug. Stiripentol has been characterized in its supercooled liquid, amorphous (glass), and crystalline states by the concurrent use of broadband dielectric spectroscopy (BDS), differential scanning calorimetry, X-ray diffraction, and optical microscopy. BDS was employed to study both the dipolar molecular dynamics and the kinetics of crystallization from the melt. Three different molecular relaxation dynamics were identified: an α relaxation corresponding to the collective reorientation of the molecules and associated with the glass transition (Tg = 246.2 ± 0.5 K), a Johari Goldstein ß relaxation that can be associated with the single-molecule precursor of the α process, and a γ relaxation arising from intramolecular motions. Isothermal crystallization of Stiripentol was studied by means of BDS well above the glass transition (between 273 and 293 K), and it was observed under optical microscope at ambient conditions. Stiripentol did not exhibit any sign of polymorphism at ambient pressure, and it recrystallized from the melt into its stable crystalline form. The crystallization kinetics did not obey the Avrami law. Stiripentol displayed a very low nucleation rate, and drops of liquid stiripentol were observed to crystallize completely from a single nucleus before the appearance of new nuclei, so that the crystallite grew according to the morphology of the liquid domains, a fact that might explain the lack of validity of the Avrami law. Possible correlations between the crystallization kinetics and the molecular dynamics have been analyzed, finding that the crystallization time has a sublinear dependence on the cooperative relaxation time, as is the case in other substances reported in the scientific literature. This could suggest a general correlation of these parameters, at least at temperatures above Tg. The low nucleation rate is an interesting feature in the quest of possible mechanisms that allow enhancing the physical stability of amorphous drugs.


Assuntos
Dioxolanos/química , Anticonvulsivantes/química , Varredura Diferencial de Calorimetria , Cristalização , Espectroscopia Dielétrica , Cinética , Simulação de Dinâmica Molecular , Temperatura , Temperatura de Transição , Difração de Raios X
14.
Sci Rep ; 7(1): 7470, 2017 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-28785030

RESUMO

Water is the most important plasticizer of biological and organic hydrophilic materials, which generally exhibit enhanced mechanical softness and molecular mobility upon hydration. The enhancement of the molecular dynamics upon mixing with water, which in glass-forming systems implies a lower glass transition temperature (T g ), is considered a universal result of hydration. In fact, even in the cases where hydration or humidification of an organic glass-forming sample result in stiffer mechanical properties, the molecular mobility of the sample almost always increases with increasing water content, and its T g decreases correspondingly. Here, we present an experimental report of a genuine antiplasticizing effect of water on the molecular dynamics of a small-molecule glass former. In detail, we show that addition of water to prilocaine, an active pharmaceutical ingredient, has the same effect as that of an applied pressure, namely, a decrease in mobility and an increase of T g . We assign the antiplasticizing effect to the formation of prilocaine-H 2 O dimers or complexes with enhanced hydrogen bonding interactions.

15.
Phys Chem Chem Phys ; 19(20): 12665-12673, 2017 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-28474037

RESUMO

The solvation of prilocaine has been investigated in pure water and in an amphiphilic methanol/water solution using a combination of neutron diffraction with isotopic substitution augmented by Empirical Potential Structure Refinement (EPSR) simulations. This combination of techniques allows for details of the solvation structure on the atomic scale to be unravelled. The hydration of prilocaine is significantly altered relative to when this molecule is in pure water (as a hydrochloride salt) or in an amphiphilic environment (as a freebase compound). Interestingly, there is not a significant change in hydration around the amine group on prilocaine hydrochloride compared with prilocaine as a freebase. Despite this group being an ammonium group in water and an amine group in methanol/water solutions, the hydration of this motif remains largely intact. The changes in hydration between prilocaine as a free base and prilocaine·HCl instead appears to arise from a change in hydration around the aromatic ring and the amide group in the prilocaine molecule.

18.
Retina ; 33(3): 522-31, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22990317

RESUMO

PURPOSE: To compare the durability of Kenalog, Trivaris, Triesence, and compounding pharmacy preservative-free triamcinolone acetonide in pigmented rabbits with syneretic vitreous using direct visualization, pharmacodynamics, and pharmacokinetics. METHODS: Twenty-five Dutch-belted rabbits were used. Pharmacokinetic experiment: Rabbits were intravitreally injected with one of four 4-mg triamcinolone acetonide formulations. Wide-field imaging was serially performed to document residual drug mass. Pharmacodynamics experiment: Four triamcinolone acetonide groups and one control group received intravitreal recombinant human vascular endothelial growth factor 165 every 2 weeks and were followed with fluorescein angiography to assess vascular endothelial growth factor retinal vasculopathy as a measure of residual steroid effect. Particle size of the formulations was measured with Mastersizer 2000. RESULTS: Remaining triamcinolone acetonide mass after 19 weeks: 12,091 ± 2,512 pixels for the Kenalog group, 1,307.36 ± 695.57 for Trivaris, 5577 ± 1477 for Triesence, and 1,535 ± 329 for compounded preservative-free triamcinolone acetonide. Kenalog suppressed recombinant human vascular endothelial growth factor-induced retinopathy more effectively than the other triamcinolone acetonide groups at Week 39, the final time point assessed. Particle size (90th percentile) was 47 µm for Kenalog, 26 µm for Triesence, and 22 µm for both compounded preservative-free triamcinolone acetonide and Trivaris. CONCLUSION: Triamcinolone acetonide formulations do not have the same pharmacokinetics/pharmacodynamics. Kenalog has the longest vitreous visibility and durability. Particle size appears to correlate with efficacy and durability.


Assuntos
Glucocorticoides/farmacologia , Glucocorticoides/farmacocinética , Neovascularização Retiniana/metabolismo , Triancinolona Acetonida/farmacologia , Triancinolona Acetonida/farmacocinética , Corpo Vítreo/metabolismo , Animais , Disponibilidade Biológica , Composição de Medicamentos , Angiofluoresceinografia , Glucocorticoides/química , Meia-Vida , Injeções Intravítreas , Tamanho da Partícula , Conservantes Farmacêuticos , Coelhos , Proteínas Recombinantes , Neovascularização Retiniana/induzido quimicamente , Neovascularização Retiniana/prevenção & controle , Solubilidade , Triancinolona Acetonida/química , Fator A de Crescimento do Endotélio Vascular/sangue , Fator A de Crescimento do Endotélio Vascular/toxicidade
19.
Invest Ophthalmol Vis Sci ; 51(2): 952-9, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19797225

RESUMO

PURPOSE: To establish the identity of a prominent protein, approximately 70 kDa, that is markedly increased in the retina of monkeys with experimental glaucoma compared with the fellow control retina, the relationship to glaucoma severity, and its localization in the retina. METHODS: Retinal extracts were subjected to 2-D gel electrophoresis to identify differentially expressed proteins. Purified peptides from the abundant 70 kDa protein were analyzed and identified by liquid chromatography/mass spectrometry/mass spectrometry (LC/MS/MS) separation, and collision-induced dissociation sequencing. Protein identity was performed on MASCOT (Matrix Science, Boston, MA) and confirmed by Western blot. The relationship between the increase in this protein and glaucoma severity was investigated by regression analyses. Protein localization in retina was evaluated by immunohistochemistry with confocal imaging. RESULTS: The abundant protein was identified as Macaca mulatta serum albumin precursor (67 kDa) from eight non-overlapping proteolytic fragments, and the identity was confirmed by Western blot. The average increase in retinal albumin content was 2.3 fold (P = 0.015). In glaucoma eyes, albumin was localized to some neurons of the inner nuclear layer, in the inner plexiform layer, and along the vitreal surface, but it was only found in blood vessels in control retinas. CONCLUSIONS: Albumin is the abundant protein found in the glaucomatous monkey retinas. The increased albumin is primarily localized to the inner retina where oxidative damage associated with experimental glaucoma is known to be prominent. Since albumin is a major antioxidant, the increase of albumin in the retinas of eyes with experimental glaucoma may serve to protect the retina against oxidative damage.


Assuntos
Modelos Animais de Doenças , Glaucoma/metabolismo , Retina/metabolismo , Albumina Sérica/metabolismo , Sequência de Aminoácidos , Animais , Western Blotting , Eletroforese em Gel Bidimensional , Eletroforese em Gel de Poliacrilamida , Feminino , Glaucoma/fisiopatologia , Pressão Intraocular , Macaca mulatta , Masculino , Microscopia Confocal , Dados de Sequência Molecular , Precursores de Proteínas/química , Precursores de Proteínas/metabolismo , Proteômica , Ratos , Ratos Wistar , Albumina Sérica/química , Espectrometria de Massas em Tandem , Tonometria Ocular
20.
PLoS One ; 3(12): e3931, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19079596

RESUMO

Glaucoma is a widespread ocular disease and major cause of blindness characterized by progressive, irreversible damage of the optic nerve. Although the degenerative loss of retinal ganglion cells (RGC) and visual deficits associated with glaucoma have been extensively studied, we hypothesize that glaucoma will also lead to alteration of the circadian timing system. Circadian and non-visual responses to light are mediated by a specialized subset of melanopsin expressing RGCs that provide photic input to mammalian endogenous clock in the suprachiasmatic nucleus (SCN). In order to explore the molecular, anatomical and functional consequences of glaucoma we used a rodent model of chronic ocular hypertension, a primary causal factor of the pathology. Quantitative analysis of retinal projections using sensitive anterograde tracing demonstrates a significant reduction (approximately 50-70%) of RGC axon terminals in all visual and non-visual structures and notably in the SCN. The capacity of glaucomatous rats to entrain to light was challenged by exposure to successive shifts of the light dark (LD) cycle associated with step-wise decreases in light intensity. Although glaucomatous rats are able to entrain their locomotor activity to the LD cycle at all light levels, they require more time to re-adjust to a shifted LD cycle and show significantly greater variability in activity onsets in comparison with normal rats. Quantitative PCR reveals the novel finding that melanopsin as well as rod and cone opsin mRNAs are significantly reduced in glaucomatous retinas. Our findings demonstrate that glaucoma impacts on all these aspects of the circadian timing system. In light of these results, the classical view of glaucoma as pathology unique to the visual system should be extended to include anatomical and functional alterations of the circadian timing system.


Assuntos
Ritmo Circadiano/fisiologia , Glaucoma/fisiopatologia , Animais , Axônios/metabolismo , Biomarcadores/metabolismo , Ritmo Circadiano/efeitos da radiação , Regulação da Expressão Gênica/efeitos da radiação , Corpos Geniculados/citologia , Corpos Geniculados/efeitos da radiação , Pressão Intraocular/fisiologia , Pressão Intraocular/efeitos da radiação , Fotocoagulação a Laser , Luz , Masculino , Atividade Motora/fisiologia , Opsinas/genética , Opsinas/metabolismo , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/genética , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Células Ganglionares da Retina/citologia , Células Ganglionares da Retina/metabolismo , Células Ganglionares da Retina/efeitos da radiação , Colículos Superiores/citologia , Colículos Superiores/efeitos da radiação , Núcleo Supraquiasmático/citologia , Núcleo Supraquiasmático/efeitos da radiação , Fatores de Tempo , Vias Visuais/fisiopatologia , Vias Visuais/efeitos da radiação
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