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1.
Gastroenterology ; 159(1): 273-288, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32169429

RESUMO

BACKGROUND & AIMS: We investigated mechanisms of hepatic stellate cell (HSC) activation, which contributes to liver fibrogenesis. We aimed to determine whether activated HSCs increase glycolysis, which is regulated by 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase-3 (PFKFB3), and whether this pathway might serve as a therapeutic target. METHODS: We performed studies with primary mouse HSCs, human LX2 HSCs, human cirrhotic liver tissues, rats and mice with liver fibrosis (due to bile duct ligation [BDL] or administration of carbon tetrachloride), and CPEB4-knockout mice. Glycolysis was inhibited in cells and mice by administration of a small molecule antagonist of PFKFB3 (3-[3-pyridinyl]-1-[4-pyridinyl]-2-propen-1-one [3PO]). Cells were transfected with small interfering RNAs that knock down PFKFB3 or CPEB4. RESULTS: Up-regulation of PFKFB3 protein and increased glycolysis were early and sustained events during HSC activation and accompanied by increased expression of markers of fibrogenesis; incubation of HSCs with 3PO or knockdown of PFKFB3 reduced their activation and proliferation. Mice with liver fibrosis after BDL had increased hepatic PFKFB3; injection of 3PO immediately after the surgery prevented HSC activation and reduced the severity of liver fibrosis compared with mice given vehicle. Levels of PFKFB3 protein were increased in fibrotic liver tissues from patients compared with non-fibrotic liver. Up-regulation of PFKFB3 in activated HSCs did not occur via increased transcription, but instead via binding of CPEB4 to cytoplasmic polyadenylation elements within the 3'-untranslated regions of PFKFB3 messenger RNA. Knockdown of CPEB4 in LX2 HSCs prevented PFKFB3 overexpression and cell activation. Livers from CPEB4-knockout had decreased PFKFB3 and fibrosis after BDL or administration of carbon tetrachloride compared with wild-type mice. CONCLUSIONS: Fibrotic liver tissues from patients and rodents (mice and rats) have increased levels of PFKFB3 and glycolysis, which are essential for activation of HSCs. Increased expression of PFKFB3 is mediated by binding of CPEB4 to its untranslated messenger RNA. Inhibition or knockdown of CPEB4 or PFKFB3 prevents HSC activation and fibrogenesis in livers of mice.


Assuntos
Células Estreladas do Fígado/patologia , Cirrose Hepática Experimental/patologia , Cirrose Hepática/patologia , Fosfofrutoquinase-2/metabolismo , Proteínas de Ligação a RNA/metabolismo , Animais , Tetracloreto de Carbono/toxicidade , Linhagem Celular , Regulação da Expressão Gênica , Técnicas de Silenciamento de Genes , Glicólise , Humanos , Fígado/citologia , Fígado/patologia , Cirrose Hepática Experimental/induzido quimicamente , Cirrose Hepática Experimental/genética , Masculino , Camundongos , Camundongos Knockout , Fosfofrutoquinase-2/genética , Cultura Primária de Células , Proteínas de Ligação a RNA/genética , Ratos , Regulação para Cima
2.
Adv Exp Med Biol ; 1122: 73-100, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30937864

RESUMO

This review chapter describes the current knowledge about the nature of pericytes in the gut, their interaction with endothelial cells in blood vessels, and their pathophysiological functions in the setting of chronic liver disease. In particular, it focuses on the role of these vascular cell types and related molecular signaling pathways in pathological angiogenesis associated with liver disease and in the establishment of the gut-vascular barrier and the potential implications in liver disease through the gut-liver axis.


Assuntos
Trato Gastrointestinal/citologia , Neovascularização Patológica , Pericitos/citologia , Transdução de Sinais , Vasos Sanguíneos/citologia , Células Endoteliais/citologia , Humanos , Hepatopatias
3.
Int J Mol Sci ; 20(15)2019 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-31344857

RESUMO

Current treatments for diabetic retinopathy (DR) target late stages when vision has already been significantly affected. Accumulating evidence suggests that neuroinflammation plays a major role in the pathogenesis of DR, resulting in the disruption of the blood-retinal barrier. Suppressors of cytokine signaling (SOCS) are cytokine-inducible proteins that function as a negative feedback loop regulating cytokine responses. On this basis, the aim of the present study was to evaluate the effect of a SOCS1-derived peptide administered by eye drops (2 weeks) on retinal neuroinflammation and early microvascular abnormalities in a db/db mouse model. In brief, we found that SOCS1-derived peptide significantly reduced glial activation and neural apoptosis induced by diabetes, as well as retinal levels of proinflammatory cytokines. Moreover, a significant improvement of electroretinogram parameters was observed, thus revealing a clear impact of the histological findings on global retinal function. Finally, SOCS1-derived peptide prevented the disruption of the blood-retinal barrier. Overall, our results suggest that topical administration of SOCS1-derived peptide is effective in preventing retinal neuroinflammation and early microvascular impairment. These findings could open up a new strategy for the treatment of early stages of DR.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Retinopatia Diabética/tratamento farmacológico , Inflamação/tratamento farmacológico , Proteína 1 Supressora da Sinalização de Citocina/farmacologia , Animais , Retinopatia Diabética/genética , Retinopatia Diabética/patologia , Modelos Animais de Doenças , Eletrorretinografia , Humanos , Inflamação/genética , Inflamação/patologia , Camundongos , Soluções Oftálmicas/farmacologia , Peptídeos/química , Peptídeos/farmacologia , Retina/efeitos dos fármacos , Retina/patologia , Proteína 1 Supressora da Sinalização de Citocina/química
4.
Int J Mol Sci ; 19(11)2018 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-30428543

RESUMO

Experimental evidence suggests that endothelin 1 (ET-1) is involved in the development of retinal microvascular abnormalities induced by diabetes. The effects of ET-1 are mediated by endothelin A- and B-receptors (ETA and ETB). Endothelin B-receptors activation mediates retinal neurodegeneration but there are no data regarding the effectiveness of ETB receptor blockage in arresting retinal neurodegeneration induced by diabetes. The main aim of the present study was to assess the usefulness of topical administration of bosentan (a dual endothelin receptor antagonist) in preventing retinal neurodegeneration in diabetic (db/db) mice. For this purpose, db/db mice aged 10 weeks were treated with one drop of bosentan (5 mg/mL, n = 6) or vehicle (n = 6) administered twice daily for 14 days. Six non-diabetic (db/+) mice matched by age were included as the control group. Glial activation was evaluated by immunofluorescence using specific antibodies against glial fibrillary acidic protein (GFAP). Apoptosis was assessed by TUNEL method. A pharmacokinetic study was performed in rabbits. We found that topical administration of bosentan resulted in a significant decrease of reactive gliosis and apoptosis. The results of the pharmacokinetic study suggested that bosentan reached the retina through the trans-scleral route. We conclude that topical administration of bosentan was effective in preventing neurodegeneration in the diabetic retina and, therefore, could be a good candidate to be tested in clinical trials.


Assuntos
Bosentana/uso terapêutico , Diabetes Mellitus Experimental/complicações , Diabetes Mellitus Experimental/tratamento farmacológico , Retinopatia Diabética/prevenção & controle , Administração Tópica , Animais , Apoptose/efeitos dos fármacos , Retinopatia Diabética/metabolismo , Endotelina-1/metabolismo , Feminino , Proteína Glial Fibrilar Ácida/metabolismo , Humanos , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Técnicas In Vitro , Masculino , Coelhos
5.
Diabetologia ; 60(11): 2285-2298, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28779212

RESUMO

AIMS/HYPOTHESIS: The main aims of the present study were: (1) to assess the expression and content of dipeptidyl peptidase IV (DPP-IV) in human and db/db mouse retinas, and in human vitreous fluid; and (2) to determine whether the topical administration of the DPP-IV inhibitors (DPP-IVi) would prevent retinal neurodegeneration and vascular leakage in db/db mice by reducing endogenous glucagon-like peptide 1 (GLP-1) degradation. METHODS: To assess the expression and content of DPP-IV, human samples of vitreous fluid and retinas were obtained from participants with type 2 diabetes (n = 8) and age-matched non-diabetic individuals (n = 8), as well as from db/db (n = 72) and db/+ (n = 28) mice. The interventional study, which included 72 db/db mice, consisted of the topical administration (eye drops) of saxagliptin, sitagliptin or vehicle for 14 days. DPP-IV mRNA levels were assessed by RT-PCR, and protein content was measured by ELISA or western blotting. GLP-1 was assessed by immunofluorescence, and its downstream effector exchange protein activated by cAMP-1 (EPAC-1) was used as a measure of GLP-1 receptor activation. Retinal analyses were performed in vivo by electroretinography and ex vivo by RT-PCR (Epac-1, Iba-1 [also known as Aif1]), western blotting (EPAC-1, glial fibrillar acidic protein [GFAP], glutamate-aspartate transporter [GLAST]) and immunofluorescence measurements (GLP-1, GFAP, ionised calcium binding adaptor molecule 1 [IBA-1], TUNEL, GLAST, albumin and collagen IV). Glutamate was quantified by HPLC. In addition, vascular leakage was examined by the Evans Blue method. RESULTS: DPP-IV was present in human vitreous fluid but in a range 100-fold less than in plasma. Both mRNA levels and protein content were much lower in the retina than in the liver or bowel, but were significantly higher in retinal pigment epithelium (RPE) from diabetic donors in comparison to non-diabetic donors (p < 0.05). Topical treatment with DPP-IVi prevented glial activation, apoptosis and vascular leakage induced by diabetes in db/db mice (p < 0.05). Moreover, it also significantly prevented diabetes-induced functional abnormalities in the electroretinogram. A significant increase of both GLP-1 and EPAC-1 was found after treatment with DPP-IVi (p < 0.05). Furthermore, GLAST downregulation induced by diabetes was prevented, resulting in a significant reduction of extracellular glutamate concentrations. All these effects were observed without any changes in blood glucose levels. CONCLUSIONS/INTERPRETATION: The topical administration of DPP-IVi is effective in preventing neurodegeneration and vascular leakage in the diabetic retina. These effects can be attributed to an enhancement of GLP-1, but other mechanisms unrelated to the prevention of GLP-1 degradation cannot be ruled out.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Inibidores da Dipeptidil Peptidase IV/uso terapêutico , Retina/efeitos dos fármacos , Retina/patologia , Adamantano/análogos & derivados , Adamantano/uso terapêutico , Animais , Diabetes Mellitus Experimental/fisiopatologia , Dipeptídeos/uso terapêutico , Eletrorretinografia , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Humanos , Imuno-Histoquímica , Masculino , Camundongos , Fosfato de Sitagliptina/uso terapêutico
6.
Mol Vis ; 23: 853-871, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29259392

RESUMO

Purpose: We investigated the link among the proinflammatory cytokine high-mobility group box 1 (HMGB1) and 8-hydroxy-2'-deoxyguanosine (8-OHdG) as a marker of oxidative DNA damage, the endothelial adhesion molecule and oxidase enzyme vascular adhesion protein-1 (VAP-1), and the inducible cytoprotective molecule heme oxygenase-1 (HO-1) in proliferative diabetic retinopathy (PDR). We correlated the levels of these molecules with clinical disease activity and studied the proinflammatory activities of HMGB1 on rat retinas and human retinal microvascular endothelial cells (HRMECs). Methods: Vitreous samples from 47 PDR and 19 non-diabetic patients, epiretinal membranes from 11 patients with PDR, human retinas (16 from diabetic patients and 16 from non-diabetic subjects), rat retinas, and HRMECs were studied by enzyme-linked immunosorbent assay, immunohistochemistry, western blot immunofluorescence, and RT-PCR analyses. In addition, we assessed the adherence of leukocytes to HMGB1-stimulated HRMECs. Results: HMGB1, 8-OHdG, and soluble VAP-1 (sVAP-1) levels were significantly higher in vitreous samples from PDR patients than in those from non-diabetics (p = 0.001, <0.0001, <0.0001, respectively). The HMGB1, 8-OHdG, sVAP-1, and HO-1 levels in PDR with active neovascularization were significantly higher than those in inactive PDR (p = 0.025, <0.0001, <0.0001, 0.012, respectively). Significant positive correlations were observed between the levels of HMGB1 and the levels of 8-OHdG (r = 0.422; p = 0.001) and sVAP-1 (r = 0.354; p = 0.004) and between the levels of 8-OHdG and the levels of sVAP-1 (r = 0.598; p<0.0001). In epiretinal membranes, VAP-1 and 8-OHdG were expressed in vascular endothelial cells and stromal cells. Significant increases in the VAP-1 mRNA and protein levels were detected in the RPE, but not in the neuroretina of diabetic patients. Treatment of HRMEC with HMGB1, diabetes induction, and an intravitreal injection of HMGB1 in normal rats induced a significant upregulation of the adhesion molecule intercellular adhesion molecule-1 (ICAM-1) in HRMECs and retinas. On the other hand, the expressions of vascular cell adhesion molecule-1 and VAP-1 were not affected. Oral administration of the HMGB1 inhibitor glycyrrhizin in rats attenuated the diabetes-induced upregulation of the retinal ICAM-1 expression. Treatment of HRMECs with HMGB1 increased leukocyte adhesion and induced the upregulation of 8-OHdG and HO-1 and the membranous translocation of VAP-1. Conclusions: Our results suggest a potential link among the proinflammatory cytokine HMGB1, VAP-1, oxidative stress, and HO-1 in the pathogenesis of PDR.


Assuntos
Amina Oxidase (contendo Cobre)/metabolismo , Moléculas de Adesão Celular/metabolismo , Desoxiguanosina/análogos & derivados , Retinopatia Diabética/metabolismo , Proteína HMGB1/metabolismo , Heme Oxigenase-1/metabolismo , Estresse Oxidativo , 8-Hidroxi-2'-Desoxiguanosina , Adulto , Idoso , Amina Oxidase (contendo Cobre)/genética , Animais , Biomarcadores/metabolismo , Western Blotting , Moléculas de Adesão Celular/genética , Dano ao DNA , Desoxiguanosina/metabolismo , Diabetes Mellitus Experimental/metabolismo , Retinopatia Diabética/patologia , Endotélio Vascular/efeitos dos fármacos , Endotélio Vascular/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Proteína HMGB1/farmacologia , Heme Oxigenase-1/genética , Humanos , Masculino , Pessoa de Meia-Idade , RNA Mensageiro/genética , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo Real , Corpo Vítreo/metabolismo
7.
Chem Biodivers ; 14(12)2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29024401

RESUMO

Three new compounds, a bicyclogermacrene (1) and two 2,3-secoaromadendrane esters (2 and 3), together with (13S)-13-hydroxylabda-8,14-diene (4), fusicogigantone B (5), 3α,14-diacetoxy-2-hydoxybicyclogermacrene (6), fusicogigantone A (7), neofuranoplagiochilal (8), plagiochiline B (9), furanoplagiochilal (10), trans-nerolidol, spathulenol, α-tocopherol, and (+)-globulol were isolated from an Argentine collection of Plagiochila diversifolia. Their structures were elucidated by extensive mono and bidimensional NMR studies. Compounds 4, 5, and 6, incorporated to the larval diet at 100 µg per g of diet, reduced the larval growth of Spodoptera frugiperda (Lepidoptera: Noctuidae) by 70 ± 25, 57 ± 23, and 33 ± 16%, respectively. Compounds 4 and 5 produced 70% and 60% larval mortality at early instars. The latter also showed antifeedant properties in the Choice Test, with a feeding ratio of 0.54 ± 0.16.


Assuntos
Hepatófitas/química , Inseticidas/química , Animais , Argentina , Hepatófitas/metabolismo , Inseticidas/toxicidade , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Espectroscopia de Ressonância Magnética , Conformação Molecular , Spodoptera/efeitos dos fármacos , Spodoptera/crescimento & desenvolvimento
8.
Anal Chem ; 88(1): 621-8, 2016 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-26639619

RESUMO

Studying the flow of chemical moieties through the complex set of metabolic reactions that happen in the cell is essential to understanding the alterations in homeostasis that occur in disease. Recently, LC/MS-based untargeted metabolomics and isotopically labeled metabolites have been used to facilitate the unbiased mapping of labeled moieties through metabolic pathways. However, due to the complexity of the resulting experimental data sets few computational tools are available for data analysis. Here we introduce geoRge, a novel computational approach capable of analyzing untargeted LC/MS data from stable isotope-labeling experiments. geoRge is written in the open language R and runs on the output structure of the XCMS package, which is in widespread use. As opposed to the few existing tools, which use labeled samples to track stable isotopes by iterating over all MS signals using the theoretical mass difference between the light and heavy isotopes, geoRge uses unlabeled and labeled biologically equivalent samples to compare isotopic distributions in the mass spectra. Isotopically enriched compounds change their isotopic distribution as compared to unlabeled compounds. This is directly reflected in a number of new m/z peaks and higher intensity peaks in the mass spectra of labeled samples relative to the unlabeled equivalents. The automated untargeted isotope annotation and relative quantification capabilities of geoRge are demonstrated by the analysis of LC/MS data from a human retinal pigment epithelium cell line (ARPE-19) grown on normal and high glucose concentrations mimicking diabetic retinopathy conditions in vitro. In addition, we compared the results of geoRge with the outcome of X(13)CMS, since both approaches rely entirely on XCMS parameters for feature selection, namely m/z and retention time values. To ensure data traceability and reproducibility, and enabling for comparison with other existing and future approaches, raw LC/MS files have been deposited in MetaboLights (MTBLS213) and geoRge is available as an R script at https://github.com/jcapelladesto/geoRge.


Assuntos
Marcação por Isótopo , Metabolômica , Software , Células Cultivadas , Cromatografia Líquida de Alta Pressão , Humanos , Espectrometria de Massas , Conformação Molecular
9.
Med Oral Patol Oral Cir Bucal ; 21(1): e95-102, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26615503

RESUMO

BACKGROUND: The aim of this study was to evaluate the clinical and microbiological impact of an antibacterial suture (Monocryl® Plus) in the surgical removal of I3M. MATERIAL AND METHODS: A "split-mouth", prospective pilot clinical study was designed involving 20 patients programmed for the surgical removal of I3M. Each side was randomly sutured with Monocryl® Plus or silk suture and removed for microbiological study 72 hours and 7 days after surgery. Presence of SSI, wound bleeding and the degree of discomfort associated with each type of suture material (scored by means of a visual analog scale) were evaluated. The level of contamination of each material was observed under the scanning electron microscope. RESULTS: Wound bleeding upon suture removing was slightly greater after 72 hours and 7 days with black silk suture, though the differences were not statistically significant (p=0.752 and p=0.113, respectively). Patient discomfort was very similar with both types of suture material (p=0.861). Only one case of SSI was recorded with black silk suture after 72 hours. Microbiologically, the antibacterial suture showed a lesser presence of microorganisms (p<0.001, at 72h and p=0.033 at 7th day, respectively). The most common bacterial species included grampositive cocci (Streptococcus viridans group, Neisseria spp., Coagulasenegative Staphylococcus and Peptostreptococcus), gramnegative cocci (Veillonella), grampositive Bacilli (Lactobacillus), and gramnegative Bacilli (Prevotella). CONCLUSIONS: The greatest antibacterial effect of Monocryl Plus suture was observed after 72 hours. According to most authors, there is no doubt that this antibacterial suture can provide little safety in the control of SSI.


Assuntos
Antibacterianos/administração & dosagem , Dioxanos , Dente Serotino/cirurgia , Poliésteres , Seda , Suturas , Adolescente , Adulto , Feminino , Humanos , Masculino , Projetos Piloto , Estudos Prospectivos , Dente Impactado , Adulto Jovem
10.
Mem Inst Oswaldo Cruz ; 109(2): 256-8, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24676660

RESUMO

Several parasitological studies carried out in El Salvador between 2000-2012 showed a higher frequency of acute cases of Chagas disease than that in other Central American countries. There is an urgent need for improved Chagas disease surveillance and vector control programs in the provinces where acute Chagas disease occurs and throughout El Salvador as a whole.


Assuntos
Doença de Chagas/epidemiologia , Doenças Negligenciadas/epidemiologia , Adolescente , Adulto , Animais , Doença de Chagas/prevenção & controle , Criança , Pré-Escolar , El Salvador/epidemiologia , Humanos , Lactente , Controle de Insetos , Trypanosoma cruzi/isolamento & purificação , Adulto Jovem
11.
Mol Vis ; 19: 47-53, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23335850

RESUMO

PURPOSE: Diabetic retinopathy (DR) has been classically considered a microcirculatory disease of the retina. However, before any microcirculatory abnormalities can be detected in ophthalmoscopic examination, retinal neurodegeneration is already present. The aim of the study was to analyze proapoptotic and survival signaling in the neuroretinas of diabetic patients at early stages of DR. METHODS: The retinas from five diabetic donors at early stages of DR were compared with the retinas from five nondiabetic donors matched by age. Glial activation was evaluated by assessing glial fibrillar acidic protein (GFAP) with western blot and immunofluorescence. Proapoptotic molecules (FasL, procaspase-8, active caspase-8, total Bid, truncated Bid, Bim, and active caspase-3), as well as antiapoptotic markers (FLIP, BclxL, and cyclooxygenase-2 [COX-2]) were assessed with western blot. RESULTS: GFAP and proapoptotic molecules (FasL, active caspase-8, truncated Bid (t-Bid), Bim, and active caspase-3) were significantly increased in the neuroretinas from diabetic patients compared to the control neuroretinas. In contrast, no significant differences in the expression of the antiapoptotic markers were found. CONCLUSIONS: An imbalance between proapoptotic and survival signaling was found in diabetic neuroretinas. Our results reveal key mechanistic pathways involved in the neurodegenerative process that occurs in the early stages of DR.


Assuntos
Apoptose/fisiologia , Sobrevivência Celular/fisiologia , Retinopatia Diabética/metabolismo , Retinopatia Diabética/patologia , Retina/metabolismo , Retina/patologia , Idoso , Proteína Agonista de Morte Celular de Domínio Interatuante com BH3/metabolismo , Biomarcadores/metabolismo , Estudos de Casos e Controles , Caspase 3/metabolismo , Caspase 8/metabolismo , Retinopatia Diabética/etiologia , Proteína Ligante Fas/metabolismo , Proteína Glial Fibrilar Ácida/metabolismo , Humanos , Pessoa de Meia-Idade , Degeneração Neural/etiologia , Degeneração Neural/metabolismo , Degeneração Neural/patologia , Transdução de Sinais/fisiologia
12.
Diabetes Metab Res Rev ; 29(6): 499-506, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23568601

RESUMO

BACKGROUND: Diabetic macular edema is the main cause of visual impairment in diabetic patients. The aim of the present study was to explore the differential proteomic pattern of the vitreous fluid from diabetic macular edema patients by means of fluorescence-based difference gel electrophoresis (DIGE). METHODS: Samples of vitreous from eight type 2 diabetic patients [four with diabetic macular edema without proliferative diabetic retinopathy and four with proliferative diabetic retinopathy without diabetic macular edema), and eight from non-diabetic subjects with idiopathic macular hole (control group) were selected from our vitreous bank for proteomic analysis. To further confirm the potential candidates identified by DIGE, 18 additional samples (six proliferative diabetic retinopathy, six diabetic macular edema and six macular hole, matched by age) were analysed by enzyme-linked immuno sorbent assay (ELISA). RESULTS: Selecting an abundance ratio of 1.5-fold, p < 0.05, as the threshold for the study, four proteins were specifically associated with diabetic macular edema. Hemopexin was significantly higher in the vitreous fluid of patients with diabetic macular edema in comparison with both control subjects and proliferative diabetic retinopathy patients. By contrast, clusterin, transthyretin and crystallin S were significantly decreased in the vitreous of patients with diabetic macular edema. The differential production of hemopexin, clusterin and transthyretin was further confirmed by ELISA. CONCLUSIONS: Proteomic analysis by DIGE was useful in identifying new potential candidates involved in the pathogenesis of diabetic macular edema. These results could open up new strategies in the treatment of diabetic macular edema.


Assuntos
Retinopatia Diabética/metabolismo , Proteínas do Olho/metabolismo , Edema Macular/metabolismo , Proteômica/métodos , Eletroforese em Gel Diferencial Bidimensional/métodos , Corpo Vítreo/química , Idoso , Estudos de Casos e Controles , Proteínas do Olho/análise , Feminino , Fluorescência , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Corpo Vítreo/metabolismo
14.
J Cell Physiol ; 227(6): 2352-62, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21826649

RESUMO

In this study, we found an imbalance between stress-mediated and survival signaling and elevated apoptotic markers in retinal pigment epithelium (RPE) from diabetic patients. Since fenofibric acid (FA) treatment reduces the progression of diabetic retinopathy (DR), we investigated the effect of hyperglycemia and hypoxia, two components of the diabetic milieu, on stress, apoptosis, and survival pathways in ARPE-19 cells (immortalized human RPE cell line) and whether FA is able to prevent the deleterious effects induced by these conditions. ARPE-19 cells cultured in high-glucose (HG) medium or under hypoxia (1% oxygen)-induced phosphorylation of the stress-activated kinases JNK and p38 MAPK. This effect was increased by the combination of both conditions. Likewise, hyperglycemia and hypoxia triggered the phosphorylation of the endoplasmic reticulum (ER) stress markers PERK and eIF2α and the induction of the pro-apoptotic transcription factor CHOP. Under these experimental conditions, reactive oxygen species (ROS) were elevated and the integrity of tight junctions was disrupted. Conversely, ARPE-19 cells treated with FA were protected against these deleterious effects induced by hyperglycemia and hypoxia. FA increased insulin-like growth factor I receptor (IGF-IR)-mediated survival signaling in cells cultured under hyperglycemia and hypoxia, thereby suppressing caspase-3 activation and down-regulation of BclxL. Moreover, FA increased LC3-II, an autophagy marker. In conclusion, our results demonstrated that FA elicits a dual protective effect in RPE by down-regulation of stress-mediated signaling and induction of autophagy and survival pathways. These molecular mechanisms could be involved in the beneficial effects of fenofibrate reported in clinical trials.


Assuntos
Retinopatia Diabética/metabolismo , Fenofibrato/farmacologia , Epitélio Pigmentado da Retina/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Estresse Fisiológico/efeitos dos fármacos , Idoso , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Biomarcadores/metabolismo , Glicemia/metabolismo , Barreira Hematorretiniana/efeitos dos fármacos , Barreira Hematorretiniana/metabolismo , Barreira Hematorretiniana/patologia , Estudos de Casos e Controles , Caspase 3/metabolismo , Hipóxia Celular , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Retinopatia Diabética/patologia , Ativação Enzimática , Fator de Iniciação 2 em Eucariotos/metabolismo , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Pessoa de Meia-Idade , Permeabilidade , Fosforilação , Espécies Reativas de Oxigênio/metabolismo , Receptor IGF Tipo 1/metabolismo , Epitélio Pigmentado da Retina/metabolismo , Epitélio Pigmentado da Retina/patologia , Fatores de Tempo , Fator de Transcrição CHOP/metabolismo , Proteína bcl-X/metabolismo , eIF-2 Quinase/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
15.
Lasers Med Sci ; 27(3): 559-66, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21617973

RESUMO

Pain, swelling, and trismus are the most common complications after surgical removal of impacted lower third molars. The aim of this study was to evaluate the analgesic and anti-inflammatory effects of a low-level laser therapy (Laser Smile™, Biolase®, San Clemente, USA) applied to the wound appeared after the surgical removal of impacted lower third molars. A prospective, randomized, and double-blind study was undertaken in 20 healthy patients with two symmetrically impacted lower third molars. The application of a low-level laser was made randomly on one of the two sides after surgery. The experimental side received 5 J/cm(2) of energy density, a wavelength of 810 nm, and an output power of 0.5 W. On the control side, a handpiece was applied intraorally, but the laser was not activated. Evaluations of postoperative pain, trismus, and swelling were made. The sample consisted of 11 women and nine men, and mean age was 23.35 years (18-37). The pain level in the first hours after surgery was lower in the experimental side than in the placebo side, although without statistically significant differences (p = 0.258). Swelling and trismus at the 2nd and 7th postoperative days were slightly higher in the control side, although not statistically significant differences were detected (p > 0.05). The application of a low-level laser with the parameters used in this study did not show beneficial affects in reducing pain, swelling, and trismus after removal of impacted lower third molars.


Assuntos
Edema/radioterapia , Lasers Semicondutores/uso terapêutico , Terapia com Luz de Baixa Intensidade , Dor Pós-Operatória/radioterapia , Extração Dentária/efeitos adversos , Trismo/radioterapia , Adolescente , Adulto , Método Duplo-Cego , Edema/etiologia , Face , Feminino , Humanos , Masculino , Dente Serotino/cirurgia , Dor Pós-Operatória/etiologia , Estudos Prospectivos , Dente Impactado/cirurgia , Trismo/etiologia , Adulto Jovem
16.
Curr Med Chem ; 29(12): 2189-2199, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34042029

RESUMO

BACKGROUND: Ezrin, radixin, and moesin (the ERM complex) interact directly with membrane proteins regulating their attachment to actin filaments. ERM protein activation modifies cytoskeleton organization and alters the endothelial barrier function, thus favoring vascular leakage. However, little is known regarding the role of ERM proteins in diabetic retinopathy (DR). OBJECTIVE: This study aimed to examine whether overexpression of the ERM complex exists in db/db mice and its main regulating factors. METHODS: 9 male db/db mice and 9 male db/+ aged 14 weeks were analyzed. ERM proteins were assessed by western blot and by immunohistochemistry. Vascular leakage was determined by the Evans blue method. To assess ERM regulation, HRECs were cultured in a medium containing 5.5 mM D-glucose (mimicking physiological conditions) and 25 mM D-glucose (mimicking hyperglycemia that occurs in diabetic patients). Moreover, treatment with TNF-α, IL-1ß, or VEGF was added to a high glucose condition. The expression of ERM proteins was quantified by RT-PCR. Cell permeability was evaluated by measuring movements of FITC-dextran. RESULTS: A significant increase of ERM in diabetic mice in comparison with non-diabetic mice was observed. A high glucose condition alone did not have any effect on ERM expression. However, TNF-α and IL-1ß induced a significant increase in ERM proteins. CONCLUSION: The increase of ERM proteins induced by diabetes could be one of the mechanisms involved in vascular leakage and could be considered as a therapeutic target. Moreover, the upregulation of the ERM complex by diabetes is induced by inflammatory mediators rather than by high glucose itself.


Assuntos
Diabetes Mellitus Experimental , Retinopatia Diabética , Animais , Diabetes Mellitus Experimental/tratamento farmacológico , Glucose , Humanos , Masculino , Camundongos , Permeabilidade , Fator de Necrose Tumoral alfa
17.
Acta Diabetol ; 59(11): 1437-1442, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35925404

RESUMO

AIMS: The response to Glucagon-like peptide-1 receptor agonists (GLP-1RAs) is highly varia-ble among patients. Thus, the identification of predictive biomarkers of therapeutic response to GLP-1 RA could help us to optimize the use of this class of drugs. GLP-1RAs increase exchange proteins directly activated by cAMP (EPAC). The aim of the present study was to assess whether the increase of EPAC1 after GLP-1RAs treatment could be a biomarker of clinical response. METHODS: After showing that GLP-1 (10 ng/mL) significantly increased the expression of EPAC1 in human endo-thelial vascular cells (HUVEC), a pilot clinical study was planned. For this purpose 49 patients with type 2 diabetes who started treatment with liraglutide were included. EPAC1 concentration was determined by ELISA before and at one month of liraglutide treatment. RESULTS: We found that serum concentration of EPAC1 increased significantly after treatment with liraglutide. Only in those patients in whom EPAC1 increased (64%), a significant decrease in HbA1c, LDL-C, body mass index (BMI), and waist circumference was shown. CONCLUSIONS: This pilot study suggests that the increase of circulating EPAC1 after GLP-1RAs treatment could be a useful biomarker to predict clinical GLP1-RAs response.


Assuntos
Diabetes Mellitus Tipo 2 , Receptor do Peptídeo Semelhante ao Glucagon 1 , Biomarcadores , LDL-Colesterol , Peptídeo 1 Semelhante ao Glucagon/uso terapêutico , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Hemoglobinas Glicadas/metabolismo , Fatores de Troca do Nucleotídeo Guanina , Humanos , Hipoglicemiantes/uso terapêutico , Liraglutida/uso terapêutico , Projetos Piloto
18.
Diabetes ; 71(2): 315-320, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34737187

RESUMO

To evaluate the effect of liraglutide, a glucagon-like peptide 1 receptor agonist, on pulmonary function and serum levels of surfactant protein D (SP-D) in type 2 diabetes. A double-blind, randomized, crossover, placebo-controlled clinical trial comprising 76 patients with a baseline forced expiratory volume in 1 s <90% of that predicted. Liraglutide was administered for 7 weeks (2 weeks of titration plus 5 weeks at 1.8 mg daily). This short duration was intentional to minimize weight loss as a potential confounding factor. Serum level of SP-D was used as a biomarker of alveolar-capillary barrier integrity. Liraglutide exerted a positive impact on forced vital capacity (FVC) in comparison with placebo (ΔFVC 5.2% of predicted [from 0.8 to 9.6]; P = 0.009). No differences in the other pulmonary variables were observed. Participants under liraglutide treatment also experienced a decrease in serum SP-D (P = 0.038). The absolute change in FVC correlated with final serum SP-D in participants receiving liraglutide (r = -0.313, P = 0.036). Stepwise multivariate regression analysis showed that final serum SP-D independently predicted changes in FVC. In conclusion, liraglutide increased FVC in patients with type 2 diabetes. This effect was associated with a significant decrease of circulating SP-D, thus pointing to a beneficial effect in the alveolar-capillary function.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Liraglutida/uso terapêutico , Pulmão/efeitos dos fármacos , Idoso , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Estudos Cross-Over , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/fisiopatologia , Método Duplo-Cego , Feminino , Controle Glicêmico , Humanos , Pulmão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Proteína D Associada a Surfactante Pulmonar/sangue , Espanha , Capacidade Vital/efeitos dos fármacos
19.
Front Neurosci ; 16: 858049, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35600617

RESUMO

Persons with type 2 diabetes born in the regions of famine exposures have disproportionally elevated risk of vision-threatening proliferative diabetic retinopathy (PDR) in adulthood. However, the underlying mechanisms are not known. In the present study, we aimed to investigate the plausible molecular factors underlying progression to PDR. To study the association of genetic variants with PDR under the intrauterine famine exposure, we analyzed single nucleotide polymorphisms (SNPs) that were previously reported to be associated with type 2 diabetes, glucose, and pharmacogenetics. Analyses were performed in the population from northern Ukraine with a history of exposure to the Great Ukrainian Holodomor famine [the Diagnostic Optimization and Treatment of Diabetes and its Complications in the Chernihiv Region (DOLCE study), n = 3,583]. A validation of the top genetic findings was performed in the Hong Kong diabetes registry (HKDR, n = 730) with a history of famine as a consequence of the Japanese invasion during WWII. In DOLCE, the genetic risk for PDR was elevated for the variants in ADRA2A, PCSK9, and CYP2C19*2 loci, but reduced at PROX1 locus. The association of ADRA2A loci with the risk of advanced diabetic retinopathy in famine-exposed group was further replicated in HKDR. The exposure of embryonic retinal cells to starvation for glucose, mimicking the perinatal exposure to famine, resulted in sustained increased expression of Adra2a and Pcsk9, but decreased Prox1. The exposure to starvation exhibited a lasting inhibitory effects on neurite outgrowth, as determined by neurite length. In conclusion, a consistent genetic findings on the famine-linked risk of ADRA2A with PDR indicate that the nerves may likely to be responsible for communicating the effects of perinatal exposure to famine on the elevated risk of advanced stages of diabetic retinopathy in adults. These results suggest the possibility of utilizing neuroprotective drugs for the prevention and treatment of PDR.

20.
Diabetes Metab Res Rev ; 26(5): 386-92, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20578202

RESUMO

BACKGROUND: To evaluate whether intensive insulin therapy leads to changes in macular biometrics (volume and thickness) in newly diagnosed diabetic patients with acute hyperglycaemia and its relationship with serum levels of vascular endothelial growth factor (VEGF) and its soluble receptor (sFlt-1). METHODS: Twenty-six newly diagnosed diabetic patients admitted to our hospital to initiate intensive insulin treatment were prospectively recruited. Examinations were performed on admission (day 1) and during follow-up (days 3, 10 and 21) and included a questionnaire regarding the presence of blurred vision, standardized refraction measurements and optical coherence tomography. Plasma VEGF and sFlt-1 were assessed by ELISA at baseline and during follow-up. RESULTS: At study entry seven patients (26.9%) complained of blurred vision and five (19.2%) developed burred vision during follow-up. Macular volume and thickness increased significantly (p = 0.008 and p = 0.04, respectively) in the group with blurred vision at day 3 and returned to the baseline value at 10 days. This pattern was present in 18 out of the 24 eyes from patients with blurred vision. By contrast, macular biometrics remained unchanged in the group without blurred vision. We did not detect any significant changes in VEGF levels during follow-up. By contrast, a significant reduction of sFlt-1 was observed in those patients with blurred vision at day 3 (p = 0.03) with normalization by day 10. CONCLUSION: Diabetic patients with blurred vision after starting insulin therapy present a significant transient increase in macular biometrics which is associated with a decrease in circulating sFlt-1.


Assuntos
Retinopatia Diabética/diagnóstico , Insulina/uso terapêutico , Macula Lutea/fisiopatologia , Edema Macular/diagnóstico , Fator A de Crescimento do Endotélio Vascular/sangue , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/sangue , Adulto , Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Retinopatia Diabética/patologia , Feminino , Humanos , Edema Macular/patologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Tomografia de Coerência Óptica , Acuidade Visual
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