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1.
Inflammopharmacology ; 32(1): 287-305, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37991660

RESUMO

Pulmonary fibrosis is a devastating disorder distinguished by redundant inflammation and matrix accumulation in the lung interstitium. The early inflammatory cascade coupled with recurring tissue injury orchestrates a set of events marked by perturbed matrix hemostasis, deposition of matrix proteins, and remodeling in lung tissue. Numerous investigations have corroborated a direct correlation between the NLR family pyrin domain-containing 3 (NLRP3) activation and the development of pulmonary fibrosis. Dysregulated activation of NLRP3 within the pulmonary microenvironment exacerbates inflammation and may incite fibrogenic responses. Nevertheless, the precise mechanisms through which the NLRP3 inflammasome elicits pro-fibrogenic responses remain inadequately defined. Contemporary findings suggest that the pro-fibrotic consequences stemming from NLRP3 signaling primarily hinge on the action of interleukin-1ß (IL-1ß). IL-1ß instigates IL-1 receptor signaling, potentiating the activity of transforming growth factor-beta (TGF-ß). This signaling cascade, in turn, exerts influence over various transcription factors, including SNAIL, TWIST, and zinc finger E-box-binding homeobox 1 (ZEB 1/2), which collectively foster myofibroblast activation and consequent lung fibrosis. Here, we have connected the dots to illustrate how the NLRP3 inflammasome orchestrates a multitude of signaling events, including the activation of transcription factors that facilitate myofibroblast activation and subsequent lung remodeling. In addition, we have highlighted the prominent role played by various cells in the formation of myofibroblasts, the primary culprit in lung fibrosis. We also provided a concise overview of various compounds that hold the potential to impede NLRP3 inflammasome signaling, thus offering a promising avenue for the treatment of pulmonary fibrosis.


Assuntos
Inflamassomos , Fibrose Pulmonar , Humanos , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Fibrose Pulmonar/tratamento farmacológico , Inflamação , Fatores de Transcrição
2.
Pharmacol Res ; 175: 106018, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34863823

RESUMO

The nuclear factor erythroid-derived 2-related factor 2 (NFE2L2/Nrf2) is a pivotal facilitator of cytoprotective responses against the oxidative/electrophilic insults. Upon activation, Nrf2 induces transcription of a wide range of cytoprotective genes having antioxidant response element (ARE) in their promoter region. Dysfunction in Nrf2 signaling has been linked to the pathogenesis of AD and several studies have suggested that boosting Nrf2 expression/activity by genetic or pharmacological approaches is beneficial in AD. Among the diverse mechanisms that regulate the Nrf2 signaling, miRNAs-mediated regulation of Nrf2 has gained much attention in recent years. Several miRNAs have been reported to directly repress the post-transcriptional expression of Nrf2 and thereby negatively regulate the Nrf2-dependent cellular cytoprotective response in AD. Moreover, several Nrf2 targeting miRNAs are misregulated in AD brains. This review is focused on the role of misregulated miRNAs that directly target Nrf2, in AD pathophysiology. Here, alongside a general description of functional interactions between miRNAs and Nrf2, we have reviewed the evidence indicating the possible role of these miRNAs in AD pathogenesis.


Assuntos
Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , MicroRNAs , Fator 2 Relacionado a NF-E2/metabolismo , Animais , Humanos , Fator 2 Relacionado a NF-E2/química , Transcrição Gênica
3.
Pharmacol Res ; 167: 105414, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33524540

RESUMO

Cardiac fibrosis is characterized by excessive deposition of extracellular matrix proteins and myofibroblast differentiation. Our previous findings have implicated resistin in cardiac fibrosis; however, the molecular mechanisms underlying this process are still unclear. Here we investigated the role of resistin in fibroblast-to-myofibroblast differentiation and elucidated the pathways involved in this process. Fibroblast-to-myofibroblast transdifferentiation was induced with resistin or TGFß1 in NIH-3T3 and adult cardiac fibroblasts. mRNA and protein expression of fibrotic markers were analyzed by qPCR and immunoblotting. Resistin-knockout mice, challenged with a high-fat diet (HFD) for 20 weeks to stimulate cardiac impairment, were analyzed for cardiac function and fibrosis using histologic and molecular methods. Cardiac fibroblasts stimulated with resistin displayed increased fibroblast-to-myofibroblast conversion, with increased levels of αSma, col1a1, Fn, Ccn2 and Mmp9, with remarkable differences in the actin network appearance. Mechanistically, resistin promotes fibroblast-to-myofibroblast transdifferentiation and fibrogenesis via JAK2/STAT3 and JNK/c-Jun signaling pathways, independent of TGFß1. Resistin-null mice challenged with HFD showed an improvement in cardiac function and a decrease in tissue fibrosis and reduced mRNA levels of fibrogenic markers. These findings are the first to delineate the role of resistin in the process of cardiac fibroblast-to-myofibroblast differentiation via JAK/STAT3 and JNK/c-Jun pathways, potentially leading to stimulation of cardiac fibrosis.


Assuntos
Transdiferenciação Celular/fisiologia , Fibroblastos/metabolismo , Sistema de Sinalização das MAP Quinases/fisiologia , Miócitos Cardíacos/metabolismo , Resistina/farmacologia , Fator de Transcrição STAT3/metabolismo , Animais , Transdiferenciação Celular/efeitos dos fármacos , Feminino , Fibroblastos/efeitos dos fármacos , Células HEK293 , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Janus Quinases/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Miócitos Cardíacos/efeitos dos fármacos , Células NIH 3T3 , Resistina/deficiência
4.
Development ; 140(4): 843-52, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23325759

RESUMO

Environmental factors can stably perturb the epigenome of exposed individuals and even that of their offspring, but the pleiotropic effects of these factors have posed a challenge for understanding the determinants of mitotic or transgenerational inheritance of the epigenetic perturbation. To tackle this problem, we manipulated the epigenetic states of various target genes using a tetracycline-dependent transcription factor. Remarkably, transient manipulation at appropriate times during embryogenesis led to aberrant epigenetic modifications in the ensuing adults regardless of the modification patterns, target gene sequences or locations, and despite lineage-specific epigenetic programming that could reverse the epigenetic perturbation, thus revealing extraordinary malleability of the fetal epigenome, which has implications for 'metastable epialleles'. However, strong transgenerational inheritance of these perturbations was observed only at transgenes integrated at the Col1a1 locus, where both activating and repressive chromatin modifications were heritable for multiple generations; such a locus is unprecedented. Thus, in our inducible animal models, mitotic inheritance of epigenetic perturbation seems critically dependent on the timing of the perturbation, whereas transgenerational inheritance additionally depends on the location of the perturbation. In contrast, other parameters examined, particularly the chromatin modification pattern and DNA sequence, appear irrelevant.


Assuntos
Cromatina/metabolismo , Colágeno Tipo I/genética , Epigênese Genética/fisiologia , Padrões de Herança/fisiologia , Modelos Biológicos , Fenótipo , Animais , Antígenos CD4/genética , Cromatina/genética , Imunoprecipitação da Cromatina , Cadeia alfa 1 do Colágeno Tipo I , Epigênese Genética/genética , Citometria de Fluxo , Proteínas de Fluorescência Verde/metabolismo , Padrões de Herança/genética , Camundongos , Camundongos Transgênicos , Transgenes/genética
5.
Life Sci ; 347: 122651, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38642844

RESUMO

Calcium ion (Ca2+) dysregulation is one of the main causes of neuronal cell death and brain damage after cerebral ischemia. During ischemic stroke, the ability of neurons to maintain Ca2+ homeostasis is compromised. Ca2+ regulates various functions of the nervous system, including neuronal activity and adenosine triphosphate (ATP) production. Disruptions in Ca2+ homeostasis can trigger a cascade of events, including activation of the unfolded protein response (UPR) pathway, which is associated with endoplasmic reticulum (ER) stress and mitochondrial dysfunction. This response occurs when the cell is unable to manage protein folding within the ER due to various stressors, such as a high influx of Ca2+. Consequently, the UPR is initiated to restore ER function and alleviate stress, but prolonged activation can lead to mitochondrial dysfunction and, ultimately, cell death. Hence, precise regulation of Ca2+ within the cell is mandatory. The ER and mitochondria are two such organelles that maintain intracellular Ca2+ homeostasis through various calcium-operating channels, including ryanodine receptors (RyRs), inositol trisphosphate receptors (IP3Rs), sarco/endoplasmic reticulum calcium ATPases (SERCAs), the mitochondrial Na+/Ca2+ exchanger (NCLX), the mitochondrial calcium uniporter (MCU) and voltage-dependent anion channels (VDACs). These channels utilize Ca2+ sequestering and release mechanisms to maintain intracellular Ca2+ homeostasis and ensure proper cellular function and survival. The present review critically evaluates the significance of Ca2+ and its physiological role in cerebral ischemia. We have compiled recent findings on calcium's role and emerging treatment strategies, particularly targeting mitochondria and the endoplasmic reticulum, to address Ca2+ overload in cerebral ischemia.


Assuntos
Cálcio , Morte Celular , AVC Isquêmico , Neurônios , Humanos , AVC Isquêmico/metabolismo , AVC Isquêmico/patologia , Animais , Cálcio/metabolismo , Neurônios/metabolismo , Neurônios/patologia , Mitocôndrias/metabolismo , Estresse do Retículo Endoplasmático/fisiologia , Retículo Endoplasmático/metabolismo , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patologia , Resposta a Proteínas não Dobradas , Sinalização do Cálcio/fisiologia , Homeostase
6.
ACS Chem Neurosci ; 15(1): 31-55, 2024 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-38118278

RESUMO

Neuroinflammation is a key pathophysiological feature of stroke-associated brain injury. A local innate immune response triggers neuroinflammation following a stroke via activating inflammasomes. The nucleotide-binding oligomerization domain leucine-rich repeat and pyrin domain-containing protein 3 (NLRP3) inflammasome has been heavily implicated in stroke pathobiology. Following a stroke, several stimuli have been suggested to trigger the assembly of the NLRP3 inflammasome. Recent studies have advanced the understanding and revealed several new players regulating NLRP3 inflammasome-mediated neuroinflammation. This article discussed recent advancements in NLRP3 assembly and highlighted stroke-induced mitochondrial dysfunction as a major checkpoint to regulating NLRP3 activation. The NLRP3 inflammasome activation leads to caspase-1-dependent maturation and release of IL-1ß, IL-18, and gasdermin D. In addition, genetic or pharmacological inhibition of the NLRP3 inflammasome activation and downstream signaling has been shown to attenuate brain infarction and improve the neurological outcome in experimental models of stroke. Several drug-like small molecules targeting the NLRP3 inflammasome are in different phases of development as novel therapeutics for various inflammatory conditions, including stroke. Understanding how these molecules interfere with NLRP3 inflammasome assembly is paramount for their better optimization and/or development of newer NLRP3 inhibitors. In this review, we summarized the assembly of the NLRP3 inflammasome and discussed the recent advances in understanding the upstream regulators of NLRP3 inflammasome-mediated neuroinflammation following stroke. Additionally, we critically examined the role of the NLRP3 inflammasome-mediated signaling in stroke pathophysiology and the development of therapeutic modalities to target the NLRP3 inflammasome-related signaling for stroke treatment.


Assuntos
Lesões Encefálicas , Acidente Vascular Cerebral , Humanos , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Doenças Neuroinflamatórias , Acidente Vascular Cerebral/tratamento farmacológico , Interleucina-1beta/metabolismo
7.
BMC Biol ; 10: 96, 2012 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-23198860

RESUMO

BACKGROUND: Conditional gene knockout (cKO) mediated by the Cre/LoxP system is indispensable for exploring gene functions in mice. However, a major limitation of this method is that gene KO is not reversible. A number of methods have been developed to overcome this, but each method has its own limitations. RESULTS: We describe a simple method we have named LOFT [LoxP-flippase (FLP) recognition target (FRT) Trap], which is capable of reversible cKO and free of the limitations associated with existing techniques. This method involves two alleles of a target gene: a standard floxed allele, and a multi-functional allele bearing an FRT-flanked gene-trap cassette, which inactivates the target gene while reporting its expression with green fluorescent protein (GFP); the trapped allele is thus a null and GFP reporter by default, but is convertible into a wild-type allele. The floxed and trapped alleles can typically be generated using a single construct bearing a gene-trap cassette doubly flanked by LoxP and FRT sites, and can be used independently to achieve conditional and constitutive gene KO, respectively. More importantly, in mice bearing both alleles and also expressing the Cre and FLP recombinases, sequential function of the two enzymes should lead to deletion of the target gene, followed by restoration of its expression, thus achieving reversible cKO. LOFT should be generally applicable to mouse genes, including the growing numbers of genes already floxed; in the latter case, only the trapped alleles need to be generated to confer reversibility to the pre-existing cKO models. LOFT has other applications, including the creation and reversal of hypomorphic mutations. In this study we proved the principle of LOFT in the context of T-cell development, at a hypomorphic allele of Baf57/Smarce1 encoding a subunit of the chromatin-remodeling Brg/Brahma-associated factor (BAF) complex. Interestingly, the FLP used in the current work caused efficient reversal in peripheral T cells but not thymocytes, which is advantageous for studying developmental epigenetic programming of T-cell functions, a fundamental issue in immunology. CONCLUSIONS: LOFT combines well-established basic genetic methods into a simple and reliable method for reversible gene targeting, with the flexibility of achieving traditional constitutive and conditional KO.


Assuntos
Técnicas de Inativação de Genes , Engenharia Genética/métodos , Alelos , Animais , Proteínas Cromossômicas não Histona/genética , Proteínas Cromossômicas não Histona/metabolismo , Regulação da Expressão Gênica/fisiologia , Marcação de Genes , Vetores Genéticos , Integrases , Camundongos , Camundongos Knockout , Subunidades Proteicas
8.
Drug Discov Today ; 28(6): 103583, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37028501

RESUMO

Sirtuin 3 (SIRT3), a mitochondrial deacetylase expressed preferentially in high-metabolic-demand tissues including the brain, requires NAD+ as a cofactor for catalytic activity. It regulates various processes such as energy homeostasis, redox balance, mitochondrial quality control, mitochondrial unfolded protein response, biogenesis, dynamics and mitophagy by altering protein acetylation status. Reduced SIRT3 expression or activity causes hyperacetylation of hundreds of mitochondrial proteins, which has been linked with neurological abnormalities, neuro-excitotoxicity and neuronal cell death. A body of evidence has suggested, SIRT3 activation as a potential therapeutic modality for age-related brain abnormalities and neurodegenerative disorders.


Assuntos
Doenças Neurodegenerativas , Sirtuína 3 , Humanos , Sirtuína 3/metabolismo , Proteínas Mitocondriais/metabolismo , Mitocôndrias/metabolismo , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/metabolismo , Biologia
9.
Drug Discov Today ; 28(5): 103555, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36931386

RESUMO

Tailoring drug products to personalized medicines poses challenges for conventional dosage forms. The prominent reason is the restricted availability of flexible dosage strengths in the market. Inappropriate dosage strengths lead to adverse drug reactions or compromised therapeutic effects. The situation worsens when the drug has a narrow therapeutic window. To overcome these challenges, data-enriched edible pharmaceuticals (DEEP) are novel concepts for designing solid oral products. DEEP have individualized doses and information embedded in quick response (QR) code form. When data are presented in a QR code, the information is printed with edible ink that contains the drug in tailored doses required for the patients.


Assuntos
Sistemas de Liberação de Medicamentos , Medicina de Precisão , Humanos , Preparações Farmacêuticas , Tecnologia Farmacêutica , Formas de Dosagem
10.
Mol Neurobiol ; 58(9): 4575-4587, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34110602

RESUMO

Severe acute respiratory syndrome coronavirus (SARS-CoV)-2 or COVID-19 has been declared as a pandemic disease by the World Health Organization (WHO). Globally, this disease affected 159 million of the population and reported ~ 3.3 million deaths to the current date (May 2021). There is no definitive treatment strategy that has been identified, although this disease has prevailed in its current form for the past 18 months. The main challenges in the (SARS-CoV)-2 infections are in identifying the heterogeneity in viral strains and the plausible mechanisms of viral infection to human tissues. In parallel to the investigations into the patho-mechanism of SARS-CoV-2 infection, understanding the fundamental processes underlying the clinical manifestations of COVID-19 is very crucial for designing effective therapies. Since neurological symptoms are very apparent in COVID-19 infected patients, here, we tried to emphasize the involvement of redox imbalance and subsequent mitochondrial dysfunction in the progression of the COVID-19 infection. It has been articulated that mitochondrial dysfunction is very apparent and also interlinked to neurological symptoms in COVID-19 infection. Overall, this article provides an in-depth overview of redox imbalance and mitochondrial dysfunction involvement in aggravating COVID-19 infection and its probable contribution to the neurological manifestation of the disease.


Assuntos
COVID-19/complicações , Mitocôndrias/fisiologia , SARS-CoV-2/patogenicidade , Animais , Antivirais/farmacologia , Antivirais/uso terapêutico , COVID-19/metabolismo , Sistema Nervoso Central/virologia , Reposicionamento de Medicamentos , Endotélio Vascular/fisiopatologia , Endotélio Vascular/virologia , Humanos , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/patologia , Modelos Biológicos , Nervo Olfatório/virologia , Especificidade de Órgãos , Oxirredução , Estresse Oxidativo/efeitos dos fármacos , Pandemias , SARS-CoV-2/fisiologia , Proteínas Virais/fisiologia , Tropismo Viral , Viremia/complicações , Virulência , Internalização do Vírus
11.
Drug News Perspect ; 23(4): 241-56, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20520853

RESUMO

Peroxisome proliferator-activated receptor gamma (PPARgamma) has already been considered as an attractive therapeutic target for the treatment of metabolic disorders. Recently, PPARgamma agonists were shown to effectively attenuate oxidative stress, inflammation and apoptosis in the central nervous system. There are several preclinical and clinical studies indicating neuroprotective potential of PPARgamma agonists in the treatment of cerebral ischemia, Parkinson's disease, Alzheimer's disease, multiple sclerosis and amyotrophic lateral sclerosis. In these disorders, apart from inhibiting oxidative stress, inflammation and apoptosis, PPARgamma agonists have the potential to modulate various signaling molecules/pathways, including matrix metalloproteinase-9, mitogen-activated protein kinases, signal transducer and activator of transcription, mitochondrial uncoupling protein 2, mitoNEET expression, amyloid precursor protein degradation, beta-site amyloid precursor protein cleaving enzyme 1 and Wnt signaling. This article discusses evidence and mechanisms supporting the neuroprotective effects of PPARgamma agonists in central nervous system disorders.


Assuntos
Fármacos Neuroprotetores/farmacologia , PPAR gama/agonistas , Doença de Alzheimer/tratamento farmacológico , Secretases da Proteína Precursora do Amiloide/genética , Animais , Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Ácido Aspártico Endopeptidases/genética , Isquemia Encefálica/tratamento farmacológico , Humanos , Inibidores de Metaloproteinases de Matriz , Esclerose Múltipla/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , PPAR gama/fisiologia , Doença de Parkinson/tratamento farmacológico
12.
Pulm Pharmacol Ther ; 22(3): 183-9, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19073273

RESUMO

Airway dysfunction and pulmonary neutrophilic inflammation are the major characteristics of inflammatory conditions of lungs like chronic obstructive pulmonary disease (COPD). Lipopolysaccharide (LPS), a constituent of cigarette smoke, has been identified as the most important risk factor for COPD development. Inhalation exposure to LPS or cigarette smoke elicits an inflammatory response accompanied by airway hyperresponsiveness, elevated proinflammatory mediators and inflammatory cells similar to COPD. In the present study, we have evaluated the effects of pioglitazone, a peroxisome proliferator-activated receptor gamma (PPAR gamma) agonist, in LPS-induced pulmonary dysfunction, inflammatory changes and oxidative stress in guinea pigs. Inhalation exposure to nebulised LPS (30 microg ml(-1)) resulted in significant increase in the breathing frequency and bronchoconstriction accompanied with a significant decrease in tidal volume. Our results demonstrated that the LPS-induced pulmonary dysfunction was temporally associated with neutrophil infiltration as evident from heavy neutrophilia, increased TNFalpha in bronchoalveolar lavage fluid (BAL), elevated myeloperoxidase (MPO) level and histology of the lung tissue. Exposure to LPS also produced significant increase in tissue malondialdehyde (MDA) level indicating underlying oxidative stress. The results also reveal that pioglitazone (3, 10 and 30 mg kg(-1), p.o.) is effective in abrogating the pulmonary dysfunction by attenuating neutrophilia, TNFalpha release and oxidative stress in LPS-induced model of acute lung inflammation. Results from the present study have added to the emergent body of evidence that PPAR gamma agonists are effective in the therapy of inflammatory disease of the lungs.


Assuntos
Lipopolissacarídeos , Pneumopatias/induzido quimicamente , Pneumopatias/tratamento farmacológico , Neutrófilos/patologia , PPAR gama/agonistas , Pneumonia/induzido quimicamente , Pneumonia/tratamento farmacológico , Tiazolidinedionas/uso terapêutico , Administração por Inalação , Animais , Líquido da Lavagem Broncoalveolar/citologia , Proteínas de Escherichia coli/toxicidade , Cobaias , Contagem de Leucócitos , Pulmão/enzimologia , Pulmão/metabolismo , Pulmão/patologia , Masculino , Malondialdeído/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Peroxidase/metabolismo , Inibidores de Fosfodiesterase/farmacologia , Pioglitazona , Pletismografia Total , Pneumonia/patologia , Rolipram/farmacologia , Fator de Necrose Tumoral alfa/metabolismo
13.
Eur J Pharmacol ; 596(1-3): 77-83, 2008 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-18768138

RESUMO

Diabetic neuropathy, a major complication of diabetes, affects more than 60% of diabetic patients. Recently, involvement of peroxynitrite has been postulated in diabetic neuropathy. In the present study, we have studied the effects of peroxynitrite decomposition catalysts (PDC's)-5,10,15,20-tetrakis(4-sulfonatophenyl) porphyrinato iron(III) [FeTPPS] and 5,10,15,20-tetrakis(N-methyl-4-pyridyl)porphyrinato iron(III) [FeTMPyP]-in experimental diabetic neuropathy. Male Sprague-Dawley rats, with six weeks of untreated diabetes were treated for two weeks with peroxynitrite decomposition catalysts. Diabetic animals showed a significant decrease in motor nerve conduction velocity and nerve blood flow, nociception as evident from decreased tail flick latency (hyperalgesia) and increased paw withdrawal pressure (mechanical allodynia) along with elevation in peroxynitrite and reduction in nerve glutathione levels. Two weeks treatment with PDC's significantly improved all the above stated functional and biochemical deficits. Aftermath of this study advocates the beneficial effects of peroxynitrite decomposition catalysts in experimental diabetic neuropathy.


Assuntos
Neuropatias Diabéticas/tratamento farmacológico , Metaloporfirinas/farmacologia , Ácido Peroxinitroso/metabolismo , Animais , Glicemia/análise , Catálise , Neuropatias Diabéticas/metabolismo , Neuropatias Diabéticas/fisiopatologia , Glutationa/metabolismo , Masculino , Metaloporfirinas/uso terapêutico , Condução Nervosa , Poli Adenosina Difosfato Ribose/metabolismo , Ratos , Ratos Sprague-Dawley , Fluxo Sanguíneo Regional , Nervo Isquiático/irrigação sanguínea , Nervo Isquiático/metabolismo , Tirosina/análogos & derivados , Tirosina/metabolismo
14.
Life Sci ; 82(11-12): 570-6, 2008 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-18262571

RESUMO

Peripheral diabetic neuropathy is a heterogeneous group of disorders, and is known to affect 50-60% of diabetic patients. Poly (ADP-ribose) polymerase (PARP) activation has been identified as one of the key components in the pathogenesis of diabetic neuropathy. In the present study we have targeted PARP overactivation in diabetic neuropathy using a known PARP inhibitor, 4 amino 1, 8-napthalimide (4-ANI). Streptozotocin induced diabetic rats developed neuropathy within 6 weeks, which was evident from significant reduction in motor nerve conduction velocity (MNCV), nerve blood flow (NBF) along with neuropathic pain and abnormal sensory perception. Six weeks after diabetes induction Sprague Dawley rats were treated with 4-ANI (3 and 10 mg/kg, p.o.) for a period of two weeks (seventh and eighth weeks). Two week treatment with 4-ANI showed improvement in nerve conduction, nerve blood flow and reduction in tail flick responses and mechanical allodynia in diabetic animals. 4-ANI also attenuated PAR immunoreactivity and NAD depletion in nerves of diabetic animals. Results of present study suggest the potential of PARP inhibitors like 4-ANI in the treatment of diabetic neuropathy.


Assuntos
1-Naftilamina/análogos & derivados , Diabetes Mellitus Experimental , Neuropatias Diabéticas/enzimologia , Naftalimidas/metabolismo , Naftalimidas/uso terapêutico , Inibidores de Poli(ADP-Ribose) Polimerases , Quinolonas/metabolismo , Quinolonas/uso terapêutico , 1-Naftilamina/química , 1-Naftilamina/metabolismo , 1-Naftilamina/farmacologia , 1-Naftilamina/uso terapêutico , Animais , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/enzimologia , Humanos , Masculino , NAD/metabolismo , Naftalimidas/química , Naftalimidas/farmacologia , Condução Nervosa/efeitos dos fármacos , Condução Nervosa/fisiologia , Medição da Dor , Poli(ADP-Ribose) Polimerases/metabolismo , Quinolonas/química , Quinolonas/farmacologia , Ratos , Ratos Sprague-Dawley , Estreptozocina
15.
Life Sci ; 80(13): 1236-44, 2007 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-17289084

RESUMO

Oxidative stress has been implicated in pathophysiology of diabetic neuropathy. All the pathways responsible for development of diabetic neuropathy are linked to oxidative stress in one way or the other. In the present study, we have targeted oxidative stress in diabetic neuropathy using resveratrol, a potent antioxidant. Eight weeks streptozotocin-diabetic rats developed neuropathy which was evident from significant reduction in motor nerve conduction velocity (MNCV), nerve blood flow (NBF) and increased thermal hyperalgesia. The 2-week treatment with resveratrol (10 and 20 mg/kg, i.p.) started 6 weeks after diabetes induction significantly ameliorated the alterations in MNCV, NBF, and hyperalgesia. Resveratrol also attenuated enhanced levels of malondialdehyde (MDA), peroxynitrite and produced increase in catalase levels in diabetic rats. There was marked reduction in DNA fragmentation observed after resveratrol treatment in diabetic rats as evident from decrease in Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) positive cells in sciatic nerve sections. Results of the present study suggest the potential of resveratrol in treatment of diabetic neuropathy and its protective effect may be mediated through reduction in oxidative stress and DNA fragmentation.


Assuntos
Antioxidantes/uso terapêutico , Fragmentação do DNA/efeitos dos fármacos , Diabetes Mellitus Experimental/tratamento farmacológico , Neuropatias Diabéticas/tratamento farmacológico , Condução Nervosa/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Nervo Isquiático/efeitos dos fármacos , Estilbenos/uso terapêutico , Animais , Apoptose/efeitos dos fármacos , Glicemia/análise , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Experimental/fisiopatologia , Neuropatias Diabéticas/metabolismo , Neuropatias Diabéticas/fisiopatologia , Relação Dose-Resposta a Droga , Humanos , Marcação In Situ das Extremidades Cortadas , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Medição da Dor , Limiar da Dor/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Fluxo Sanguíneo Regional/efeitos dos fármacos , Resveratrol , Nervo Isquiático/irrigação sanguínea , Nervo Isquiático/patologia , Nervo Isquiático/fisiopatologia
16.
Neurol Res ; 29(3): 304-9, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17509231

RESUMO

OBJECTIVES: In the present study, we have investigated the neuroprotective potential of 6hydroxy-2,5,7,8-tetramethylchroman-2-carboxylic acid (Trolox), in middle cerebral artery occlusion (MCAO) induced focal cerebral ischemia. METHODS: Sprague-Dawley rats were subjected to 2 hours of MCAO followed by 22 or 70 hours of reperfusion. After reperfusion, rats were evaluated for neurological deficits and cerebral infarction. Brain malondialdehyde (MDA) level and in situ terminal deoxynucleotidyl transferase mediated dUTP-biotin nick end labeling (TUNEL) were also estimated. RESULTS: Focal cerebral ischemia produced a significant infarct volume and neurological scores as compared with sham-operated animals. Cerebral ischemia reperfusion injury was associated with an increase in lipid peroxidation in ipsilateral and contralateral hemisphere of brain along with an increase in TUNEL positive cells in ipsilateral hemisphere of brain sections indicating oxidative stress and DNA fragmentation, respectively. Trolox (10 and 30 mg/kg, i.p.) treatment significantly decreased neurological damage which was evident from the reduction in infarct volume and neurological score. Trolox (30 mg/kg) also attenuated oxidative stress and DNA fragmentation. DISCUSSION: Oxidative stress-induced neuronal damage is implicated in the pathophysiology of cerebral ischemia. Our study suggests that Trolox is a potent neuroprotective agent in focal cerebral ischemia and its neuroprotective effects may be attributed to the reduction of lipid peroxidation and DNA fragmentation.


Assuntos
Isquemia Encefálica/prevenção & controle , Cromanos/uso terapêutico , Fármacos Neuroprotetores/uso terapêutico , Animais , Isquemia Encefálica/etiologia , Isquemia Encefálica/patologia , Fragmentação do DNA/efeitos dos fármacos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Lateralidade Funcional , Marcação In Situ das Extremidades Cortadas/métodos , Infarto da Artéria Cerebral Média/complicações , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Malondialdeído/metabolismo , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/prevenção & controle , Fatores de Tempo
17.
Life Sci ; 79(24): 2293-302, 2006 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-16935310

RESUMO

Oxidative stress induced cell injury is reported to contribute to the pathogenesis of cerebral ischemia. Reactive oxygen species such as hydrogen peroxide (H2O2) and superoxide radical along with nitric oxide and peroxynitrite generated during ischemia-reperfusion injury, causes the overactivation of poly (ADP-ribose) polymerase (PARP) leading to neuronal cell death. In the present study we have evaluated the effects of PARP inhibitor, 8-hydroxy-2 methyl-quinazolin-4-[3H]one (NU1025) in H2O2 and 3-morphilinosyndonimine (SIN-1) induced cytotoxicity in PC12 cells as well as in middle cerebral artery occlusion (MCAO) induced focal cerebral ischemia in rats. Exposure of PC12 cells to H2O2 (0.4 mM) and SIN-1 (0.8 mM) resulted in a significant decrease in cell viability after 6 h. Pretreatment with NU1025 (0.2 mM) restored cell viability to approximately 73 and 82% in H2O2 and SIN-1 injured cells, respectively. In MCAO studies, NU1025 was administered at different time points (1 h before reperfusion, immediately before reperfusion, 3 h after reperfusion and 6 h after reperfusion). NU1025 at 1 and 3 mg/kg reduced total infarct volume to 25% and 45%, respectively, when administered 1 h before reperfusion. NU1025 also produced significant improvement in neurological deficits. Neuroprotection with NU1025 was associated with reduction in PAR accumulation, reversal of brain NAD depletion and reduction in DNA fragmentation. Results of this study demonstrate the neuroprotective activity of NU1025 and suggest its potential in cerebral ischemia.


Assuntos
Apoptose/efeitos dos fármacos , Isquemia Encefálica/tratamento farmacológico , Inibidores Enzimáticos/uso terapêutico , NAD/metabolismo , Fármacos Neuroprotetores/uso terapêutico , Inibidores de Poli(ADP-Ribose) Polimerases , Quinazolinas/uso terapêutico , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patologia , Sobrevivência Celular/efeitos dos fármacos , Fragmentação do DNA , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Combinação de Medicamentos , Inibidores Enzimáticos/farmacologia , Peróxido de Hidrogênio/farmacologia , Masculino , Artéria Cerebral Média/lesões , Molsidomina/análogos & derivados , Molsidomina/farmacologia , Fármacos Neuroprotetores/farmacologia , Células PC12/efeitos dos fármacos , Células PC12/patologia , Quinazolinas/farmacologia , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologia
19.
Drug Discov Today ; 17(13-14): 793-804, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22406696

RESUMO

Increased expression of endothelin (ET) peptide and its receptors following ischemic stroke is found to regulate many critical aspects of stroke pathophysiology. Many attempts have been made to target ET receptors in various animal models of stroke, but it is very difficult to draw a definite line of conclusion, because these studies differ in many aspects, such as animal model, treatment schedule, parameters and techniques used for assessing these parameters. A meta-analysis of all studies showed a significant reduction in the lesion volume and improvement in functional outcome in focal cerebral ischemia. ET(A) receptor antagonists appear to offer an essential advantage of multiple neuroprotective mechanisms, including prevention of blood-brain barrier disruption and leukocyte infiltration.


Assuntos
Isquemia Encefálica/tratamento farmacológico , Descoberta de Drogas/métodos , Fármacos Neuroprotetores/uso terapêutico , Receptores de Endotelina/metabolismo , Acidente Vascular Cerebral/tratamento farmacológico , Animais , Isquemia Encefálica/complicações , Modelos Animais de Doenças , Descoberta de Drogas/tendências , Antagonistas dos Receptores de Endotelina , Humanos , Fármacos Neuroprotetores/administração & dosagem , Fármacos Neuroprotetores/efeitos adversos , Receptores de Endotelina/agonistas , Receptores de Endotelina/genética , Transdução de Sinais , Acidente Vascular Cerebral/etiologia
20.
Behav Brain Res ; 216(2): 606-12, 2011 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-20833208

RESUMO

Transient global cerebral ischemia results in acute neurodegeneration in selective brain areas. Global cerebral ischemic-reperfusion (IR) injury induced selective hippocampal damage results into various neurobehavioral deficits including spatial memory and learning deficiencies. In this study, we have investigated the protective effects of a nonthiazolidinedione PPARγ agonist, N-(2-benzoylphenyl)-O-[2-(methyl-2-pyridinylamino)ethyl]-l-tyrosine (GW1929), against global cerebral IR injury induced neurobehavioral deficits and brain damage in gerbils. Bilateral carotid artery occlusion induced global cerebral ischemia in gerbils resulted in neurological deficits, hyperlocomotion, reduced response latency in passive avoidance test and hippocampal damage. Hippocampal neurodegeneration after cerebral IR injury was also associated with significant increase in iNOS and MMP-9 immunoreactivity along with TNFα and IL-6 levels. Massive apoptotic DNA fragmentation as evident from increased TUNEL (terminal deoxynucleotidyl transferase mediated dUTP nick end labelling)-positive cells was also observed in the CA1 hippocampal region of IR challenged gerbils. GW1929 treatment significantly ameliorated cerebral IR induced neurological symptoms, hyperlocomotion, cognitive deficits and hippocampal neuronal damage in CA1 hippocampus region in gerbils. Significant reduction in IR injury induced iNOS and MMP-9 immunoreactivity, TNFα and IL-6 levels and apoptotic DNA fragmentation was also observed with GW1929 treatment. Pioglitazone, thiazolidinedione PPARγ agonist also exhibited similar effects on inflammatory parameters after global cerebral IR injury. In summary, this study demonstrates neuroprotective effects of GW1929 in global cerebral IR injury induced neurobehavioral deficits and brain pathology which may be attributed to reduced inflammation and apoptotic DNA fragmentation, suggesting therapeutic potential of PPARγ agonists in cerebral IR injury.


Assuntos
Benzofenonas/farmacologia , Isquemia Encefálica/tratamento farmacológico , Transtornos Cognitivos/prevenção & controle , Fármacos Neuroprotetores/farmacologia , PPAR gama/agonistas , Traumatismo por Reperfusão/tratamento farmacológico , Tirosina/análogos & derivados , Análise de Variância , Animais , Dano Encefálico Crônico/etiologia , Dano Encefálico Crônico/patologia , Dano Encefálico Crônico/prevenção & controle , Isquemia Encefálica/complicações , Isquemia Encefálica/patologia , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/patologia , Fragmentação do DNA/efeitos dos fármacos , Gerbillinae , Hipocampo/efeitos dos fármacos , Hipocampo/patologia , Masculino , Atividade Motora/efeitos dos fármacos , Traumatismo por Reperfusão/complicações , Traumatismo por Reperfusão/patologia , Tirosina/farmacologia
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