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1.
J Neurosci Res ; 99(5): 1236-1252, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33634892

RESUMO

Mindfulness is a meditation practice frequently associated with changes in subjective evaluation of cognitive and sensorial experience, as well as with modifications of brain activity and morphometry. Aside from the anatomical localization of functional changes induced by mindfulness practice, little is known about changes in functional and effective functional magnetic resonance imaging (fMRI) connectivity. Here we performed a connectivity fMRI analysis in a group of healthy individuals participating in an 8-week mindfulness-based stress reduction (MBSR) training program. Data from both a "mind-wandering" and a "meditation" state were acquired before and after the MBSR course. Results highlighted decreased local connectivity after training in the right anterior putamen and insula during spontaneous mind-wandering and the right cerebellum during the meditative state. A further effective connectivity analysis revealed (a) decreased modulation by the anterior cingulate cortex over the anterior portion of the putamen, and (b) a change in left and right posterior putamen excitatory input and inhibitory output with the cerebellum, respectively. Results suggest a rearrangement of dorsal striatum functional and effective connectivity in response to mindfulness practice, with changes in cortico-subcortical-cerebellar modulatory dynamics. Findings might be relevant for the understanding of widely documented mindfulness behavioral effects, especially those related to pain perception.


Assuntos
Cerebelo/diagnóstico por imagem , Corpo Estriado/diagnóstico por imagem , Atenção Plena/métodos , Rede Nervosa/diagnóstico por imagem , Estresse Psicológico/diagnóstico por imagem , Estresse Psicológico/terapia , Adulto , Cerebelo/fisiologia , Corpo Estriado/fisiologia , Feminino , Humanos , Masculino , Meditação/métodos , Meditação/psicologia , Rede Nervosa/fisiologia , Estresse Psicológico/psicologia
2.
Liver Int ; 40(11): 2820-2827, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32666695

RESUMO

BACKGROUND AND AIMS: HCV eradication improves non-hepatic outcomes such as cardiovascular diseases, although without clearly defined mechanisms. In this study we aimed to assess whether improvement of carotid atherosclerosis may be linked to a reduction in systemic oxidative stress after viral clearance. METHODS: We studied a retrospective cohort of 105 patients (age 62.4 ± 11.2 years; 62 men) with F3/F4 fibrosis, characterized by carotid ultrasonography at baseline and at sustained virologic response (SVR) follow-up. Levels of 8-iso-prostaglandin F2α (F2 -isoprostanes) and other oxidative stress markers were measured on frozen sera. Association between change (denoted as Δ) in oxidative stress markers (exposures) and change in carotid intima-media thickness (cIMT) (outcome) was examined using multiple linear regression. RESULTS: Subclinical atherosclerosis, defined as the presence of carotid plaque and/or cIMT ≥ 0.9, was present in 72% of the cohort. All patients achieved SVR that led to reduction in cIMT (0.92 ± 0.20 vs 0.83 ± 0.21 mm, P < .001). HCV eradication markedly decreased serum levels of F2 -isoprostanes (620.5 [143.2; 1904.1] vs 119.51 [63.2; 400.6] pg/mL, P < .0001), lipid hydroperoxides (13.8 [6.3; 20.7] vs 4.9 [2.3; 9.6] nmol/µl, P < .0001) and 8-hydroxy-2'-deoxyguanosine (558.9 [321.0; 6301.2] vs 294.51 [215.31; 408.95] pg/mL, P < .0001), whereas increased serum GPx activity (10.44 [4.6; 16.3] vs 13.75 [9.42; 20.63] nmol/min/mL, P = .001). By multiple linear regression analysis ΔcIMT was independently associated with ΔF2 -isoprostanes (ß: 1.746 [0.948; 2.543]; P < .0001) after adjustment for age, baseline F2 -isoprostanes and baseline IMT. CONCLUSIONS: Besides association of lipid peroxidation with severity of liver disease, the reduction in F2 -isoprostanes may be involved in the improvement of atherosclerosis after HCV eradication.


Assuntos
Hepacivirus , Hepatite C , Idoso , Antivirais/uso terapêutico , Espessura Intima-Media Carotídea , Hepatite C/tratamento farmacológico , Humanos , Cirrose Hepática/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Estresse Oxidativo , Estudos Retrospectivos
3.
Toxicol Appl Pharmacol ; 267(1): 30-40, 2013 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-23253326

RESUMO

During the last decade, it has been shown that the activation of NRF2 and the binding to electrophile-responsive element (EpREs), stimulates the expression of a great number of genes responsible for the synthesis of phase I and phase II proteins, including antioxidants enzymes and heme oxygenase-1 (HO-1). This critical cell response occurs in cardiovascular, degenerative and chronic infective diseases aggravated by a chronic oxidative stress. In our previous reports we have shown that ozonated plasma is able to up-regulate HO-1 expression in endothelial cells. In the present work we investigated a candidate mechanism involved in this process. After treatment with increasing doses of ozonated serum (20, 40 and 80 µg/mL O(3) per mL of serum), a clear dose dependent activation of NRF2 and the subsequent induction of HO-1 and NAD(P)H quinone oxidoreductase 1(NQO1) was observed. This effect was also present when cells were treated with serum and hydrogen peroxide (H(2)O(2)) or serum and 4-hydroxynonenal (4HNE). Moreover, the treatment with ozonated serum was associated with a dose-dependent activation of extracellular-signal-regulated kinases (ERK1/2) and p38 MAP kinases (p38), not directly involved in NRF2 activation. These data, provide a new insight on the mechanism responsible for the induction of HO-1 expression by ozonated serum in the endothelium, and have a practical importance as an expedient approach to the treatment of patients with both effective orthodox drugs and ozonated autohemotherapy, targeted to the restoration of redox homeostasis.


Assuntos
Endotélio Vascular/metabolismo , Heme Oxigenase-1/biossíntese , Fator 2 Relacionado a NF-E2/fisiologia , Ozônio/toxicidade , Soro/fisiologia , Regulação para Cima/fisiologia , Linhagem Celular , Relação Dose-Resposta a Droga , Endotélio Vascular/citologia , Endotélio Vascular/efeitos dos fármacos , Heme Oxigenase-1/sangue , Homeostase/efeitos dos fármacos , Humanos , Fator 2 Relacionado a NF-E2/sangue , Oxirredução/efeitos dos fármacos , Soro/metabolismo , Regulação para Cima/efeitos dos fármacos
4.
Mediators Inflamm ; 2013: 745984, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24027357

RESUMO

The phosphodiesterase 4 inhibitor roflumilast prevents bleomycin- (BLM-) induced lung fibrosis in animal models. However, its mechanism of action remains unknown. We investigated whether roflumilast N-oxide (RNO), the active metabolite of roflumilast, can modulate in vitro the oxidative effects of BLM on human lung fibroblasts (HLF). In addition, since BLM increases the production of F2-isoprostanes that have per se fibrogenic activity, the effect of RNO on oxidative stress and fibrogenesis induced by the F2-isoprostane 8-epi-PGF2α was investigated. HLF were preincubated either with the vehicle or with RNO and exposed to either BLM or 8-epi-PGF2α. Proliferation and collagen synthesis were assessed as [(3)H]-thymidine and [(3)H]-proline incorporation. Reactive oxygen species (ROS) and F2-isoprostanes were measured. NADPH oxidase 4 (NOX4) protein and mRNA were also evaluated. BLM increased both cell proliferation and collagen synthesis and enhanced ROS and F2-isoprostane production. These effects were significantly prevented by RNO. Also, RNO significantly reduced the increase in both NOX4 mRNA and protein, induced by BLM. Finally, 8-epi-PGF2α per se stimulated HLF proliferation, collagen synthesis, and NOX4 expression and ROS generation, and RNO prevented these effects. Thus, the antifibrotic effect of RNO observed in vivo may be related to its ability to mitigate ROS generation via downregulation of NOX4.


Assuntos
Aminopiridinas/farmacologia , Benzamidas/farmacologia , Fibroblastos/metabolismo , Regulação Enzimológica da Expressão Gênica , Pulmão/citologia , NADPH Oxidases/metabolismo , Proliferação de Células , Células Cultivadas , Colágeno/química , Ciclopropanos/farmacologia , DNA/metabolismo , Dinoprosta/análogos & derivados , Dinoprosta/metabolismo , Regulação para Baixo , Inibidores Enzimáticos/farmacologia , Fibroblastos/efeitos dos fármacos , Fibrose , Humanos , Pulmão/patologia , NADPH Oxidase 4 , Estresse Oxidativo , Oxigênio/química , Espécies Reativas de Oxigênio/metabolismo
5.
Psychoneuroendocrinology ; 135: 105579, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34775250

RESUMO

OBJECTIVE: Mindfulness practice, a form of meditation, has shown benefit for psychological and physical health. In this study, we investigated the effect of an intensive period of Mindfulness practice on some biological mediators of stress and inflammation during a 3-day residential retreat. METHODS: A total of 95 healthy individuals (aged 18-67) were recruited and randomized to a Mindfulness retreat arm or an active control arm. Before (t0) and after (t1) the intervention, all the participants were assessed for salivary cortisol levels and for a panel of pro- and anti-inflammatory cytokines measured in saliva. Psychometric measures on stress, anxiety and awareness were carried out using PSS, STAI-Y and MAAS questionnaires, respectively. RESULTS: As to the within-group differences, we observed a statistically significant decrease in perceived stress (ß = -8.85, p < 0.0001), and anxiety scores (ß = -12.39, p < 0.0001), while awareness increased (ß = 15.26, p < 0.0001) between t0 to t1 in retreat participants. In the mindfulness intervention group, we also observed a statistically significant reduction in the levels of pro-inflammatory cytokines IL-6 (ß = -0.94 p = 0.001) and IL-8 (ß = -176.40, p < 0.0001), and an increase in anti-inflammatory IL-10 (ß = 0.89 p < 0.0001) levels at the end of the retreat. At t1 we observed a highly significant correlation between cortisol levels and both anxiety (r = 0.56, p < 0.0001) and perceived stress (r = 0.92, p < 0.0001) scores. CONCLUSIONS: Mindfulness retreat participants showed a significant reduction in perceived stress and anxiety levels, as well as an improved balance of some key mediators of inflammatory states. Our data provide evidence that a mindfulness retreat may be effective in improving physical and mental health. Future studies with larger numbers of subjects and follow-up periods may examine mindfulness practice as a non-pharmacological alternative to promote stress reduction and overall health and wellbeing.


Assuntos
Inflamação , Atenção Plena , Estresse Psicológico , Adolescente , Adulto , Idoso , Biomarcadores/análise , Citocinas/análise , Humanos , Hidrocortisona/análise , Inflamação/metabolismo , Inflamação/psicologia , Pessoa de Meia-Idade , Saliva/química , Estresse Psicológico/metabolismo , Estresse Psicológico/psicologia , Adulto Jovem
6.
Am J Physiol Lung Cell Mol Physiol ; 298(5): L704-13, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20154225

RESUMO

Cigarette smoke (CS) is a main risk factor in chronic obstructive pulmonary disease (COPD), but only 20% of smokers develop COPD, suggesting genetic predisposition. Animal studies have shown that C57BL/6J mice are sensitive to CS and develop emphysema, whereas Institute of Cancer Research (ICR) mice are not. To investigate the potential factors responsible for the different susceptibility of ICR and C57BL/6J mice to CS, we evaluated in alveolar macrophages (AMs) isolated from these strains of mice the possible mechanisms involved in the inflammatory and oxidative responses induced by CS. Lactate dehydrogenase (LDH) release revealed that C57BL/6J AMs were more susceptible to CS extract (CSE) toxicity than ICR. Differences were observed in inflammatory and oxidative response after CSE exposure. Proinflammatory cytokines and matrix metalloproteinases (MMPs) were increased in C57BL/6J but not ICR AMs. Control C57BL/6J AMs showed a higher baseline production of reactive oxygen species (ROS) and H(2)O(2) with lower baseline levels of GSH, nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1), and glutathione peroxidase (GPX2). This was associated with reduced histone deacetylase-2 (HDAC2) expression, activation of NF-κB, and higher basal levels of TNF-α and IL-6. CSE induced a decrease in HDAC2 protein levels in both C57BL/6J and ICR AMs; however, the level of HDAC2 was significantly lower in C57BL/6 than in ICR AMs. Furthermore, CSE enhanced NF-κB-dependent cytokine release only in C57BL/6J AMs. We suggest that an imbalance in oxidative stress decreases HDAC2 levels and facilitates NF-κB binding, resulting in a proinflammatory response in C57BL/6J but not in ICR AMs. These results could contribute in understanding the different susceptibility to CS of these strains of mice.


Assuntos
Macrófagos Alveolares/metabolismo , Nicotiana/toxicidade , Fumaça/efeitos adversos , Animais , Citocinas/metabolismo , Predisposição Genética para Doença , Glutationa/metabolismo , Histona Desacetilase 2/antagonistas & inibidores , Histona Desacetilase 2/metabolismo , Humanos , Mediadores da Inflamação/metabolismo , L-Lactato Desidrogenase/metabolismo , Masculino , Metaloproteinases da Matriz/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos ICR , Modelos Animais , NF-kappa B/metabolismo , Estresse Oxidativo , Doença Pulmonar Obstrutiva Crônica/etiologia , Doença Pulmonar Obstrutiva Crônica/genética , Doença Pulmonar Obstrutiva Crônica/metabolismo , Fatores de Risco , Fumar/efeitos adversos , Especificidade da Espécie
8.
Lab Invest ; 88(2): 124-31, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18158556

RESUMO

F2-isoprostanes are considered as the most reliable markers of oxidative stress and can be used to evaluate the oxidative status in a number of human pathologies. Besides being markers of oxidative stress, F2-isoprostanes proved to be mediators of important biological effects and would act through the activation of receptors analogous to those for thromboxane A2. In a previous work, we provided evidence that F(2)-isoprostanes, generated during carbon tetrachloride-induced hepatic fibrosis, mediate hepatic stellate cell (HSC) proliferation and collagen hyperproduction. To investigate whether TxA2 receptor (TxA2r or TPr) is involved in the effects of F2-isoprostanes on HSC, experiments on DNA synthesis were carried out in the presence of 8-epi-prostaglandin F(2alpha) (8-epi-PGF(2alpha)) or the TxA2r-specific agonist I-BOP ([1S-[1alpha,2alpha(Z),3beta(1E,3S*), 4alpha]]-7-[3-[3-hydroxy-4-(4-iodophenoxy)-1-butenyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptenoic acid). Both agonists significantly stimulated DNA synthesis, which was almost completely inhibited by the TxA2r-specific antagonist SQ29548 ([1S-[1alpha,2alpha(Z),3alpha,4alpha]]-7-[3-[[2-[(phenylamino)carbonyl] hydrazino] methyl]-7-oxabicyclo[2.2.1]hept-2-yl]-5-heptanoic acid), suggesting that much of the effect of 8-epi-PGF(2alpha) is mediated by the TxA2r. Further studies showed that increasing concentrations of SQ29548 progressively inhibit DNA synthesis, suggesting a possible competitive antagonism between the two molecules. In addition, we demonstrated that the stimulatory effect of 8-epi-PGF(2alpha) on collagen synthesis could be mediated by TxA2r. The occurrence of TxA2r on HSC was also investigated using western blotting analysis and immunocytochemistry, which reveals that TP is distributed both on plasma membranes and within the cells. Moreover, binding studies indicated the presence of a specific binding site for 3H-SQ29548 on HSC. Competition binding studies indicated that 8-epi-PGF(2alpha) and I-BOP were both able to displace 3H-SQ29548 binding with a very different affinity (K(i)=4.14+/-1.9 x 10(-6) M and K(i)=1.15+/-0.3 x 10(-9) M, respectively), suggesting the involvement of a modified form of isoprostane receptor, homologous to the classic thromboxane A2-binding site in F2-isoprostanes-evoked responses on HSC.


Assuntos
F2-Isoprostanos/metabolismo , Fígado/metabolismo , Pericitos/metabolismo , Receptores de Tromboxano A2 e Prostaglandina H2/metabolismo , Ligação Competitiva , Compostos Bicíclicos Heterocíclicos com Pontes , Células Cultivadas , Colágeno/biossíntese , DNA/biossíntese , Dinoprosta/análogos & derivados , Dinoprosta/farmacologia , Ácidos Graxos Insaturados , Humanos , Hidrazinas/farmacologia , Fígado/citologia , Receptores de Tromboxano A2 e Prostaglandina H2/agonistas , Trítio , Vasoconstritores/farmacologia
9.
Mol Aspects Med ; 29(1-2): 43-9, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18061254

RESUMO

After a brief introduction to oxidative stress, the discovery of F(2)-isoprostanes as specific and reliable markers of oxidative stress is described. Isoprostanes are also agonists of important biological effects. Since a relation between oxidative stress and collagen hyperproduction has been previously suggested and since lipid peroxidation products have been proposed as possible mediators of liver fibrosis, we investigated whether collagen synthesis is induced by F(2)-isoprostanes the most proximal products of lipid peroxidation. In a rat model of carbon tetrachloride-induced hepatic fibrosis, plasma isoprostanes were markedly elevated for the entire experimental period; hepatic collagen content was also increased. When hepatic stellate cells from normal liver were cultured up to activation (expression of alpha-smooth muscle-alpha actin) and then treated with F(2)-isoprostanes in the concentration range found in the in vivo studies (10(-9)-10(-8)M), a striking increase in DNA synthesis, in cell proliferation and in collagen synthesis was observed. Moreover, F(2)-isoprostanes increased the production of transforming growth factor-beta1 by U937 cells, assumed as a model of Kupffer cells or liver macrophages. The data suggest the possibility that F(2)-isoprostanes generated by lipid peroxidation in hepatocytes mediate hepatic stellate cell proliferation and collagen hyperproduction seen in hepatic fibrosis.


Assuntos
Isoprostanos/sangue , Cirrose Hepática/sangue , Animais , Proliferação de Células/efeitos dos fármacos , Colágeno/metabolismo , F2-Isoprostanos/metabolismo , F2-Isoprostanos/farmacologia , Humanos , Isoprostanos/metabolismo , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Estresse Oxidativo/efeitos dos fármacos
10.
Free Radic Biol Med ; 44(3): 247-56, 2008 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-17997380

RESUMO

F(2)-isoprostanes are not just markers of oxidative stress. The discovery of F(2)-isoprostanes (F(2)-IsoPs) as specific and reliable markers of oxidative stress in vivo is briefly summarized here. F(2)-IsoPs are also agonists of important biological effects, such as the vasoconstriction of renal glomerular arterioles, the retinal vessel, and the brain microcirculature. In addition to the F(2)-IsoPs, E(2)- and D(2)-IsoPs can be formed by rearrangement of H(2)-IsoP endoperoxides and can give rise to cyclopentenone IsoPs, which are very reactive alpha,beta-unsaturated aldehydes. The same type of reactivity is also shown by acyclic gamma-ketoaldehydes formed as products of the IsoP pathway. Because previous studies suggested a relation between oxidative stress and collagen hyperproduction, it was investigated whether collagen synthesis is induced by F(2)-IsoPs, the most proximal products of lipid peroxidation. In contrast to aldehydes, F(2)-IsoPs act through receptors able to elicit definite signal transduction pathways. In a rat model of carbon tetrachloride-induced hepatic fibrosis, plasma F(2)-IsoPs were markedly elevated for the entire experimental period; hepatic collagen content was also increased. When hepatic stellate cells from normal liver were cultured up to activation (expression of smooth muscle alpha-actin) and then treated with F(2)-IsoPs in the concentration range found in the in vivo studies (10(-9) to 10(-8) M), a striking increase in DNA synthesis, cell proliferation, and collagen synthesis was observed. Total collagen content was similarly increased. All these stimulatory effects were reversed by the specific antagonist of the thromboxane A(2) receptor, SQ 29 548, whereas the receptor agonist, I-BOP, also had a stimulatory effect. Therefore F(2)-IsoPs generated by lipid peroxidation in hepatocytes may mediate hepatic stellate cell proliferation and collagen hyperproduction seen in hepatic fibrosis.


Assuntos
F2-Isoprostanos/química , F2-Isoprostanos/metabolismo , Cirrose Hepática/etiologia , Fígado/metabolismo , Estresse Oxidativo , Animais , Biomarcadores/química , Biomarcadores/metabolismo , Colágeno/metabolismo , F2-Isoprostanos/farmacologia , Humanos , Peroxidação de Lipídeos , Fígado/efeitos dos fármacos , Fígado/patologia , Cirrose Hepática/metabolismo , Cirrose Hepática/patologia , Fibrose Pulmonar/etiologia , Ratos , Receptores de Prostaglandina/metabolismo
11.
Curr Med Chem ; 15(8): 803-808, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18393841

RESUMO

There is a pressing need for the development of new therapies for emphysema, particularly as no existing treatment has been shown to reduce disease progression. Compounds with a potential activity against the pathological mechanisms postulated to play a role in the development and progression of emphysema should be tested in vivo in animal models of this disease. The choice of the model is of capital importance. While models of elastase-induced emphysema are relatively easy to execute, require low personnel capacity and provide fast results, they also have a limited clinical relevance. On the other hand, models of chronic smoke exposure are time-consuming, expensive and require high personnel capacity but have a high clinical relevance. Presently, mainly two pharmacological approaches are being considered and investigated in experimental studies. The first approach consists of pharmacological interventions designed to slow down the rate at which alveolar wall is lost in emphysema. In this approach we find anti-inflammatory agents, protease inhibitors and antioxidants. The attempt to reduce lung inflammatory cell infiltration is most appealing since such an effect would also reduce the lung burden of both proteases and oxidants. The second approach is an attempt to reverse the process of alveolar loss by inducing alveolar growth. To our knowledge here only the effects of retinoids and/or retinoid receptor agonists have been investigated. This report presents a selected review of the literature of animal studies using these pharmacological approaches.


Assuntos
Anti-Inflamatórios/uso terapêutico , Antioxidantes/uso terapêutico , Modelos Animais de Doenças , Inibidores de Proteases/uso terapêutico , Enfisema Pulmonar/tratamento farmacológico , Animais
12.
Free Radic Biol Med ; 115: 1-9, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-29129520

RESUMO

F2-isoprostanes (F2-IsoPs) have been considered markers of oxidative stress in various pulmonary diseases, but little is known about their possible role in pulmonary fibrosis. In this study, we have investigated the potential key role of F2-IsoPs as markers and mediators of bleomycin (BLM)-induced pulmonary fibrosis in rats. During the in vivo study, plasma F2-IsoPs showed a peak at 7 days and remained elevated for the entire experimental period. Lung F2-IsoP content nearly tripled 7 days following the intratracheal instillation of BLM, and by 28 days, the value increased about fivefold compared to the controls. Collagen deposition correlated with F2-IsoP content in the lung. Furthermore, from day 21 onwards, lung sections from BLM-treated animals showed α-smooth muscle actin (α-SMA) positive cells, which were mostly evident at 28 days. In vitro studies performed in rat lung fibroblasts (RLF) demonstrated that either BLM or F2-IsoPs stimulated both cell proliferation and collagen synthesis. Moreover, RLF treated with F2-IsoPs showed a significant increase of α-SMA expression compared to control, indicating that F2-IsoPs can readily activate fibroblasts to myofibroblasts. Our data demonstrated that F2-IsoPs can be mediators of key events for the onset and development of lung fibrosis, such as cell proliferation, collagen synthesis and fibroblast activation. Immunocytochemistry analysis, inhibition and binding studies demonstrated the presence of the thromboxane A2 receptor (TP receptor) on lung fibroblasts and suggested that the observed effects may be elicited through the binding to this receptor. Our data added a new perspective on the role of F2-IsoPs in lung fibrosis by providing evidence of a profibrotic role for these mediators in the pathogenesis of pulmonary fibrosis.


Assuntos
Biomarcadores/metabolismo , F2-Isoprostanos/metabolismo , Fibroblastos/fisiologia , Pulmão/metabolismo , Miofibroblastos/fisiologia , Fibrose Pulmonar/diagnóstico , Actinas/metabolismo , Animais , Bleomicina/toxicidade , Diferenciação Celular , Proliferação de Células , Células Cultivadas , Colágeno/metabolismo , Modelos Animais de Doenças , Humanos , Pulmão/patologia , Masculino , Ratos , Ratos Sprague-Dawley
13.
Expert Opin Drug Discov ; 10(4): 399-410, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25704258

RESUMO

INTRODUCTION: Emphysema is characterized by an abnormal and permanent enlargement of airspaces accompanied by destruction of their walls. Up to now, there is no cure for emphysema, and animal models may be important for new drug discovery. AREAS COVERED: Herein, the authors review animal models of emphysema since the protease-antiprotease hypothesis as well as the results obtained with compounds tested in these models. Of particular importance are animal models of cigarette smoke exposure since it is the most important risk factor of emphysema. The authors also analyze two approaches to drug testing, that is, the approach aimed at preventing emphysema and the one aimed at reversing it. EXPERT OPINION: It has been suggested that early and late interventions do not have the same protective effect and that late interventions are much more likely to reveal treatments beneficial in humans. However, this is not always the case, and a compound that prevents emphysema when administered as an early intervention can also have the same protective effect when given as a late intervention. Furthermore, the fact that a compound detected by means of early intervention is now in clinical practice shows that early intervention studies can be predictive for efficacy in humans.


Assuntos
Desenho de Fármacos , Descoberta de Drogas/métodos , Enfisema/tratamento farmacológico , Animais , Modelos Animais de Doenças , Enfisema/etiologia , Enfisema/fisiopatologia , Humanos , Fatores de Risco , Fumar/efeitos adversos
14.
Autoimmunity ; 48(1): 46-56, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25046647

RESUMO

Oxidative stress (OS) is important in the pathogenesis of autoimmune diseases such as rheumatoid arthritis (RA) and its experimental model--adjuvant arthritis (AA). Antioxidants are scarcely studied in autoimmunity, and future analyses are needed to assess its effects in ameliorating these diseases. Although there are studies about antioxidants effects on the course of RA, their role in combination therapy has not yet been studied in detail, especially on extra-articular manifestations of AA. During the 28-d administration of pinosylvin (PIN) in monotherapy and in combination with methotrexate (MTX) to AA rats, we evaluated the impact of the treatment on selected parameters. The experiment included: healthy controls, untreated AA, AA administered 50 mg/kg b.w. of PIN daily p.o., AA administered 0.4 mg/kg b.w. of MTX twice weekly p.o. and AA treated with a combination of PIN+MTX. AA was monitored using: hind paw volume, C-reactive protein, monocyte chemotactic protein-1 (MCP-1), thiobarbituric acid reactive substances (TBARS) and F2-isoprostanes in plasma, γ-glutamyltransferase activity in spleen, activity of lipoxygenase (LOX) in lung, heme oxygenase-1 (HO-1) and nuclear factor kappa B (NF-κB) in liver and lung. PIN monotherapy significantly improved the activation of NF-κB in liver and lung, HO-1 expression and activity of LOX in the lung, MCP-1 levels in plasma (on 14th d) and plasmatic levels of F2-isoprostanes. An important contribution of PIN to MTX effect was the reduction of OS (an increase of HO-1 expression in lung and reduction of plasmatic TBARS) and decrease of LOX activity in the lung.


Assuntos
Antirreumáticos/farmacologia , Artrite Experimental/tratamento farmacológico , Artrite Experimental/metabolismo , Metotrexato/farmacologia , Estilbenos/farmacologia , Animais , Artrite Experimental/patologia , Biomarcadores/metabolismo , Proteína C-Reativa/metabolismo , Quimiocina CCL2/sangue , Sinergismo Farmacológico , Quimioterapia Combinada , F2-Isoprostanos/sangue , Heme Oxigenase-1/metabolismo , Membro Posterior , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Inflamação/patologia , Lipoxigenase/metabolismo , Fígado/efeitos dos fármacos , Fígado/metabolismo , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Masculino , NF-kappa B/metabolismo , Estresse Oxidativo , Ratos , Ratos Endogâmicos Lew , Baço/efeitos dos fármacos , Baço/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , gama-Glutamiltransferase/metabolismo
15.
Free Radic Biol Med ; 86: 156-65, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26006105

RESUMO

CDKL5 mutation is associated with an atypical Rett syndrome (RTT) variant. Recently, cholesterol homeostasis perturbation and oxidative-mediated loss of the high-density lipoprotein receptor SRB1 in typical RTT have been suggested. Here, we demonstrate an altered lipid serum profile also in CDKL5 patients with decreased levels of SRB1 and impaired activation of the defensive system Nrf2. In addition, CDKL5 fibroblasts showed an increase in 4-hydroxy-2-nonenal- and nitrotyrosine-SRB1 adducts that lead to its ubiquitination and probable degradation. This study highlights a possible common denominator between two different RTT variants (MECP2 and CDKL5) and a possible common future therapeutic target.


Assuntos
Lipídeos/sangue , Fator 2 Relacionado a NF-E2/metabolismo , Proteínas Serina-Treonina Quinases/genética , Síndrome de Rett/genética , Receptores Depuradores Classe B/genética , Espasmos Infantis/genética , Adolescente , Células Cultivadas , Criança , Pré-Escolar , Síndromes Epilépticas , Feminino , Fibroblastos/metabolismo , Expressão Gênica , Humanos , Masculino , Óxido Nítrico Sintase Tipo II/metabolismo , Estresse Oxidativo , Síndrome de Rett/sangue , Receptores Depuradores Classe B/metabolismo , Espasmos Infantis/sangue , Regulação para Cima
16.
Int J Biochem Cell Biol ; 35(4): 486-95, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12565710

RESUMO

The role of iron in initiating liver fibrosis in iron overload diseases is not clearly established. Partly, this is due to the lack of suitable animal models that can produce the full liver pathology seen in genetic hemochromatosis. Recent advances in this field have demonstrated that iron may be interacting with other potential liver-damaging agents. The aim of this study was to investigate if feeding with carbonyl iron (CI) facilitates the development of carbon tetrachloride (CCl4)-induced liver fibrosis in the mouse. Mice were given a diet containing 3% CI and treated with CCl4 intraperitoneally twice weekly and 5% alcohol added to the drinking water for 12 weeks. Hepatic iron content increased 15- and 22-fold in animals receiving CI and CI + CCl4. At histological examination, iron-laden hepatocytes were found in CI treated animals, whereas these were absent in animals not exposed to CI. Mice receiving iron-enriched diet alone showed a mild fibrosis. Conversely, a marked collagen deposition was observed in CCl4 and CI + CCl4 groups. In particular, in this latter group, there was evidence of liver cirrhosis. Biochemical evaluation of collagen content substantiated histologic analysis. These results demonstrate that the addition of iron facilitates the development of cirrhosis in animals exposed to subtoxic doses of CCl4. This model may be useful in exploring the pathogenesis of liver cirrhosis. Moreover, its use in genetically altered mouse strains might provide new insight on the role of iron in fibrosis.


Assuntos
Sobrecarga de Ferro/complicações , Cirrose Hepática Experimental/metabolismo , Animais , Tetracloreto de Carbono/toxicidade , Colágeno/metabolismo , Modelos Animais de Doenças , Compostos Carbonílicos de Ferro , Sobrecarga de Ferro/metabolismo , Ferro da Dieta/toxicidade , Cirrose Hepática Experimental/etiologia , Camundongos , Compostos Organometálicos/toxicidade
17.
Biochem Pharmacol ; 64(7): 1139-45, 2002 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-12234617

RESUMO

Various studies on hepatic fibrosis occurring in iron overload suggest that excess of tissue iron may be involved in the stimulation of collagen synthesis. Anyway, up to date, direct evidence on the role of iron in hepatic fibrosis is lacking. Moreover, it is not clear whether iron acts as direct initiator of fibrogenesis or as mediator of hepatocellular necrosis. In the present study, we investigated the effect of nontoxic doses of iron on collagen metabolism and proliferation, key features of liver fibrosis, by means of cultures of hepatic stellate cells, the liver cells responsible for collagen production. Iron treatment increased collagen synthesis without affecting noncollagen proteins. The maximum effect was observed at 5 microM iron (+132%). At this dose, no cell damage or proliferation was detected. Conversely, higher doses of iron (10 and 25 microM) induced cell proliferation and a lower increase in collagen synthesis, suggesting the prevalence of proliferative effect on the synthetic one. These effects occurred without the intervention of serum factors and were not mediated by lipid peroxidation. Our results strongly support the hypothesis that iron "per sé" may act as a profibrogenic agent. Finally, we provide evidence that iron plays a role also in matrix degradation, by stimulating some metalloprotease activities. Iron treatment increased metalloprotease-2 activity in hepatic stellate cells, while no changes were observed for interstitial collagenase activity suggesting that, in these conditions, a pathological accumulation of hepatic extracellular matrix may occur.


Assuntos
Colágeno/metabolismo , Hepatócitos/efeitos dos fármacos , Ferro/farmacologia , Metaloproteinase 2 da Matriz/metabolismo , Actinas/metabolismo , Animais , Divisão Celular/efeitos dos fármacos , Colágeno/efeitos dos fármacos , Compostos Férricos/farmacologia , Expressão Gênica/efeitos dos fármacos , Hepatócitos/metabolismo , Malondialdeído/metabolismo , Ratos , Ratos Sprague-Dawley
18.
PLoS One ; 9(10): e108359, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25330321

RESUMO

Several cross-sectional studies have documented neuroanatomical changes in individuals with a long history of meditation, while a few evidences are available about the interaction between neuroanatomical and psychological changes even during brief exposure to meditation. Here we analyzed several morphometric indexes at both cortical and subcortical brain level, as well as multiple psychological dimensions, before and after a brief -8 weeks- Mindfulness Based Stress Reduction (MBSR) training program, in a group of 23 meditation naïve-subjects compared to age-gender matched subjects. We found a significant cortical thickness increase in the right insula and the somatosensory cortex of MBSR trainees, coupled with a significant reduction of several psychological indices related to worry, state anxiety, depression and alexithymia. Most importantly, an interesting correlation between the increase in right insula thickness and the decrease in alexithymia levels during the MBSR training were observed. Moreover, a multivariate pattern classification approach allowed to identify a cluster of regions more responsive to MBSR training across subjects. Taken together, these findings documented the significant impact of a brief MBSR training on brain structures, as well as stressing the idea of MBSR as a valuable tool for alexithymia modulation, also originally providing a plausible neurobiological evidence of a major role of right insula into mediating the observed psychological changes.


Assuntos
Encéfalo/anatomia & histologia , Atenção Plena , Psicologia , Adulto , Encéfalo/fisiologia , Feminino , Humanos , Masculino , Meditação/psicologia , Neuroanatomia , Tamanho do Órgão
19.
Fundam Clin Pharmacol ; 28(6): 616-26, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24920394

RESUMO

Many of disease-modifying anti-rheumatic drugs often have side effects at high doses and/or during long-term administration. Increased efficacy without increased toxicity is expected for combination therapy of rheumatoid arthritis (RA). The aim of the study was to examine the effect of N-feruloylserotonin (N-f-5HT) and methotrexate (MTX) in monotherapy and in combination therapy on disease progression and inflammation in arthritic rats. Adjuvant arthritis was induced by intradermal injection of Mycobacterium butyricum in incomplete Freund's adjuvant in Lewis rats. The experiment included healthy animals, arthritic animals without any drug administration, arthritic animals with administration of N-f-5HT in the oral daily dose of 15 mg/kg b.w., arthritic animals with administration of MTX in the oral dose of 0.3 mg/kg b.w. twice a week and arthritic animals treated with the combination of N-f-5HT and MTX. N-f-5HT in monotherapy reduced only activation of NF-κB and did not have any significant effect on other parameters monitored. Low-dose treatment of MTX decreased the level of IL-1ß and MCP-1 on day 14 and activation of NF-κB in liver without significant effect on other parameters. N-f-5HT and MTX combination showed both the anti-arthritic (hind paw volume and arthritic score) and anti-inflammatory effect (plasmatic levels of IL-1ß, IL-17, MCP-1, CRP, and activation of NF-κB in liver). In combination with MTX, N-f-5HT markedly potentiated the therapeutic effect of MTX low dose, which resulted in significant improvement of all parameters measured. The findings showed that the combination therapy simultaneously decreased multiple markers of inflammation, a result crucial for future therapy of RA.


Assuntos
Artrite Experimental/tratamento farmacológico , Artrite Reumatoide/tratamento farmacológico , Metotrexato/farmacologia , Serotonina/análogos & derivados , Animais , Antirreumáticos/administração & dosagem , Antirreumáticos/farmacologia , Artrite Experimental/patologia , Artrite Reumatoide/patologia , Progressão da Doença , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Adjuvante de Freund/administração & dosagem , Inflamação/tratamento farmacológico , Inflamação/patologia , Masculino , Metotrexato/administração & dosagem , NF-kappa B/metabolismo , Ratos , Ratos Endogâmicos Lew , Serotonina/administração & dosagem , Serotonina/farmacologia
20.
Free Radic Biol Med ; 65: 201-207, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23792773

RESUMO

Despite evidence supporting a potential role for F2-isoprostanes (F2-IsoP's) in liver fibrosis, their signaling mechanisms are poorly understood. We have previously provided evidence that F2-IsoP's stimulate hepatic stellate cell (HSC) proliferation and collagen hyperproduction by activation of a modified form of isoprostane receptor homologous to the classic thromboxane receptor (TP). In this paper, we examined which signal transduction pathways are set into motion by F2-IsoP's to exert their fibrogenic effects. HSCs were isolated from rat liver, cultured to their activated myofibroblast-like phenotype, and then treated with the isoprostane 15-F2t-isoprostane (15-F2t-IsoP). Inositol trisphosphate (IP3) and adenosine 3',5'-cyclic monophosphate (cAMP) levels were determined using commercial kits. Mitogen-activated protein kinase (MAPK) and cyclin D1 expression was assessed by Western blotting. Cell proliferation and collagen synthesis were determined by measuring [(3)H]thymidine and [(3)H]proline incorporation, respectively. 15-F2t-IsoP elicited an activation of extracellular-signal-regulated kinase (ERK), p38 MAPK, and c-Jun NH2-terminal kinase (JNK), which are known to be also regulated by G-protein-coupled receptors. Preincubation with specific ERK (PD98059), p38 (SB203580), or JNK (SP600125) inhibitors prevented 15-F2t-IsoP-induced cell proliferation and collagen synthesis. 15-F2t-IsoP decreased cAMP levels within 30 min, suggesting binding to the TPß isoform and activation of Giα protein. Also, 15-F2t-IsoP increased IP3 levels within a few minutes, suggesting that the Gq protein pathway is also involved. In conclusion, the fibrogenic effects of F2-IsoP's in HSCs are mediated by downstream activation of MAPKs, through TP binding that couples via both Gqα and Giα proteins. Targeting TP receptor, or its downstream pathways, may contribute to preventing oxidative damage in liver fibrosis.


Assuntos
Células Estreladas do Fígado/metabolismo , Isoprostanos/metabolismo , Transdução de Sinais/fisiologia , Animais , Western Blotting , Células Cultivadas , Dinoprosta/análogos & derivados , Isoprostanos/farmacologia , Cirrose Hepática/metabolismo , Ratos , Receptores de Tromboxanos/metabolismo
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