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1.
Am J Drug Alcohol Abuse ; 44(3): 310-316, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28829626

RESUMO

BACKGROUND: Opioid use disorder during pregnancy is a growing health concern. Methadone maintenance is the treatment of choice but emerging data indicate buprenorphine is a viable alternative. Due to costs and limited accessibility of methadone, pregnant women may require transition from methadone to buprenorphine for maintenance treatment. OBJECTIVES: To assess safety and effectiveness of transitioning from methadone to buprenorphine when necessary during pregnancy. METHODS: A standardized protocol using low buprenorphine doses to minimize emergent withdrawal symptoms under careful obstetric and psychiatric monitoring was implemented in 20 pregnant women. Outpatient maternal and neonatal outcomes were assessed. RESULTS: Women maintained on an average methadone dose of 44 ± 4.77 (20-100) mg/day (mean±standard error mean (SEM); range) were successfully transitioned to 12.60 ± 0.8 (8-16) mg/day (mean±SEM; range) of buprenorphine. Within 4 weeks of transition, 15% had illicit drugs detected in urine drug screens. Ninety percent of women maintained outpatient follow-up until delivery. At delivery, 38.9% of mothers were exclusively adherent to buprenorphine (without use of illicit substances and/or other psychotropic medications); this resulted in significantly lower rates of neonatal abstinence syndrome (NAS) and shorter hospital stays. DISCUSSION: Pregnant women transitioned from methadone to buprenorphine maintenance showed maternal and neonatal outcomes comparable to studies of women on buprenorphine throughout pregnancy. Infants born to buprenorphine-maintained women who abstained from illicit substances and other prescribed psychotropic medications experienced less severe NAS and shorter hospitalizations compared with women with illicit substance use and other psychotropic medications. These findings suggest women can safely be transitioned from methadone to buprenorphine during pregnancy.


Assuntos
Analgésicos Opioides/uso terapêutico , Buprenorfina/uso terapêutico , Metadona/uso terapêutico , Síndrome de Abstinência Neonatal/prevenção & controle , Tratamento de Substituição de Opiáceos/métodos , Transtornos Relacionados ao Uso de Opioides/reabilitação , Complicações na Gravidez/reabilitação , Adulto , Substituição de Medicamentos , Feminino , Humanos , Recém-Nascido , Gravidez , Resultado da Gravidez , Resultado do Tratamento
2.
Alcohol Clin Exp Res ; 40(11): 2320-2328, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27647657

RESUMO

BACKGROUND: Ethanol (EtOH) neurotoxicity can result in devastating effects on brain and behavior by disrupting homeostatic signaling cascades and inducing cell death. One such mechanism involves double-stranded RNA activated protein kinase (PKR), a primary regulator of protein translation and cell viability in the presence of a virus or other external stimuli. EtOH-mediated up-regulation of interferon-gamma (IFN-γ; the oxidative stress-inducible regulator of PKR), PKR, and its target, p53, are still being fully elucidated. METHODS: Using Western blot analysis, immunofluorescence, and linear regression analyses, changes in the IFN-γ-PKR-p53 pathway following chronic EtOH treatment in the frontal cortex of rodents were examined. The role of PKR on cell viability was also assessed in EtOH-treated cells using PKR overexpression vector and PKR inhibitor (PKRI). RESULTS: In rats chronically fed EtOH, PKR, phosphorylated PKR (p-PKR), IFN-γ, and p53 were significantly increased following chronic EtOH exposure. Linear regression revealed a significant correlation between IFN-γ and p-PKR protein levels, as well as p-PKR expression and age of EtOH exposure. Overexpression of PKR resulted in greater cell death, while use of PKRI enhanced cell viability in EtOH-treated cells. CONCLUSIONS: Chronic EtOH exposure activates the IFN-γ-PKR-p53 pathway in the frontal cortex of rodents. p-PKR expression is greater in brains of rodents exposed to EtOH at earlier ages compared to later life, suggesting a mechanism by which young brains could be more susceptible to EtOH-related brain injury. PKR and p-PKR were also colocalized in neurons and astrocytes of rats. This study provides additional insight into biochemical mechanisms underlying alcohol use disorder related neuropathology and warrants further investigation of PKR as a potential pharmacotherapeutic target to combat EtOH-related neurotoxicity, loss of protein translation and brain injury.


Assuntos
Depressores do Sistema Nervoso Central/farmacologia , Etanol/farmacologia , Interferon gama/metabolismo , Córtex Pré-Frontal/efeitos dos fármacos , Proteína Supressora de Tumor p53/metabolismo , eIF-2 Quinase/metabolismo , Idade de Início , Animais , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Humanos , Masculino , Córtex Pré-Frontal/metabolismo , Distribuição Aleatória , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos
3.
Alcohol Clin Exp Res ; 39(3): 476-84, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25704249

RESUMO

BACKGROUND: Brain cell death is a major pathological consequence of alcohol neurotoxicity. However, the molecular cascades in alcohol-induced brain tissue injury are unclear. METHODS: Using Western blot and double immunofluorescence, we examined the expression of interferon (IFN)-induced protein kinase R (PKR), phosphorylated-PKR (p-PKR), and IFN gamma (IFNγ) in the prefrontal cortex (PFC) of postmortem brains from subjects with alcohol use disorders (AUD). RESULTS: The protein levels of PKR, p-PKR, and IFNγ were significantly increased in subjects with AUD compared with control subjects without AUD, and a younger age of onset of AUD was significantly correlated with higher protein levels of p-PKR. In addition, elevated PKR- and p-PKR-IR were observed in both neurons and astrocytes in the PFC of subjects with AUD compared to subjects without AUD. CONCLUSIONS: The activation of the IFNγ-PKR pathway in PFC of humans is associated with chronic excessive ethanol use with an age of onset dependent manner, and activation of this pathway may play a pivotal role in AUD-related brain tissue injury. This study provides insight into neurodegenerative key factors related to AUD and identifies potential targets for the treatment of alcohol-induced neurotoxicity.


Assuntos
Transtornos Relacionados ao Uso de Álcool/metabolismo , Interferon gama/biossíntese , Córtex Pré-Frontal/metabolismo , Transdução de Sinais , eIF-2 Quinase/biossíntese , Adulto , Transtornos Relacionados ao Uso de Álcool/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Córtex Pré-Frontal/patologia , Transdução de Sinais/fisiologia
4.
Alcohol Clin Exp Res ; 38(1): 144-51, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23915421

RESUMO

BACKGROUND: The biochemical pathways underlying alcohol abuse and dependence are not well understood, although brain cell loss and neurotoxicity have been reported in subjects with alcohol dependence. Monoamine oxidase B (MAO B; an enzyme that catabolizes neurotransmitters such as dopamine) is consistently increased in this psychiatric illness. MAO B has been implicated in the pathogenesis of alcohol dependence and alcohol-induced brain neurotoxicity. Recently, the cell growth inhibitor protein, Kruppel-like factor 11 (KLF11), has been reported to be an MAO transcriptional activator. KLF11 is also known as TIEG2 (transforming growth factor-beta-inducible early gene 2) and mediates apoptotic cell death. This study investigates the protein expression of KLF11 and its relationship with MAO B using human postmortem prefrontal cortex from subjects with alcohol dependence. METHODS: Twelve subjects with alcohol dependence and the respective psychiatrically normal control subjects were investigated. Expression of KLF11 and MAO B proteins in the prefrontal cortex was measured by Western blot analysis. Correlation studies involving KLF11 and MAO B protein expression were performed. Localization of KLF11 in the human prefrontal cortex was also determined by immunohistochemistry. RESULTS: Levels of KLF11 protein were significantly increased by 44% (p < 0.03) in the postmortem prefrontal cortex of subjects with alcohol dependence as compared to age- and gender-matched, psychiatrically normal control subjects. Furthermore, KLF11 levels were significantly and positively correlated with both the increased MAO B protein levels and blood alcohol content in alcohol-dependent subjects. In addition, KLF11 protein expression was visualized in both neuronal and glial cells. CONCLUSIONS: This novel study shows the important role of KLF11, an MAO transcriptional activator, in human alcohol dependence. It further supports that the KLF11-MAO B cell death cascade may contribute to chronic alcohol-induced brain damage. This argues a case for KLF11-MAO B inhibition as a novel therapeutic strategy that may impact this highly prevalent illness.


Assuntos
Alcoolismo/metabolismo , Proteínas de Ciclo Celular/biossíntese , Regulação da Expressão Gênica , Monoaminoxidase/biossíntese , Córtex Pré-Frontal/metabolismo , Proteínas Repressoras/biossíntese , Ativação Transcricional/fisiologia , Alcoolismo/patologia , Proteínas Reguladoras de Apoptose , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Córtex Pré-Frontal/patologia , Estudos Retrospectivos
5.
J Biol Chem ; 287(29): 24195-206, 2012 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-22628545

RESUMO

Chronic stress is a risk factor for psychiatric illnesses, including depressive disorders, and is characterized by increased blood glucocorticoids and brain monoamine oxidase A (MAO A, which degrades monoamine neurotransmitters). This study elucidates the relationship between stress-induced MAO A and the transcription factor Kruppel-like factor 11 (KLF11, also called TIEG2, a member of the Sp/KLF- family), which inhibits cell growth. We report that 1) a glucocorticoid (dexamethasone) increases KLF11 mRNA and protein levels in cultured neuronal cells; 2) overexpressing KLF11 increases levels of MAO A mRNA and enzymatic activity, which is further enhanced by glucocorticoids; in contrast, siRNA-mediated KLF11 knockdown reduces glucocorticoid-induced MAO A expression in cultured neurons; 3) induction of KLF11 and translocation of KLF11 from the cytoplasm to the nucleus are key regulatory mechanisms leading to increased MAO A catalytic activity and mRNA levels because of direct activation of the MAO A promoter via Sp/KLF-binding sites; 4) KLF11 knockout mice show reduced MAO A mRNA and catalytic activity in the brain cortex compared with wild-type mice; and 5) exposure to chronic social defeat stress induces blood glucocorticoids and activates the KLF11 pathway in the rat brain, which results in increased MAO A mRNA and enzymatic activity. Thus, this study reveals for the first time that KLF11 is an MAO A regulator and is produced in response to neuronal stress, which transcriptionally activates MAO A. The novel glucocorticoid-KLF11-MAO A pathway may play a crucial role in modulating distinct pathophysiological steps in stress-related disorders.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Monoaminoxidase/metabolismo , Proteínas Repressoras/metabolismo , Animais , Proteínas Reguladoras de Apoptose , Western Blotting , Proteínas de Ciclo Celular/genética , Linhagem Celular Tumoral , Células Cultivadas , Imunoprecipitação da Cromatina , Cromatografia Líquida de Alta Pressão , Corticosterona/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Dexametasona/metabolismo , Imunofluorescência , Expressão Gênica/efeitos dos fármacos , Humanos , Masculino , Camundongos , Camundongos Knockout , Monoaminoxidase/genética , Radioimunoensaio , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase em Tempo Real , Proteínas Repressoras/genética , Serotonina/metabolismo , Estresse Fisiológico/genética , Estresse Fisiológico/fisiologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
6.
Neuropharmacology ; 105: 329-340, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26805422

RESUMO

Binge drinking induces several neurotoxic consequences including oxidative stress and neurodegeneration. Because of these effects, drugs which prevent ethanol-induced damage to the brain may be clinically beneficial. In this study, we investigated the ethanol-mediated KLF11-MAO cell death cascade in the frontal cortex of Sprague-Dawley rats exposed to a modified Majchowicz 4-day binge ethanol model and control rats. Moreover, MAO inhibitors (MAOIs) were investigated for neuroprotective activity against binge ethanol. Binge ethanol-treated rats demonstrated a significant increase in KLF11, both MAO isoforms, protein oxidation and caspase-3, as well as a reduction in BDNF expression in the frontal cortex compared to control rats. MAOIs prevented these binge ethanol-induced changes, suggesting a neuroprotective benefit. Neither binge ethanol nor MAOI treatment significantly affected protein expression levels of the oxidative stress enzymes, SOD2 or catalase. Furthermore, ethanol-induced antinociception was enhanced following exposure to the 4-day ethanol binge. These results demonstrate that the KLF11-MAO pathway is activated by binge ethanol exposure and MAOIs are neuroprotective by preventing the binge ethanol-induced changes associated with this cell death cascade. This study supports KLF11-MAO as a mechanism of ethanol-induced neurotoxicity and cell death that could be targeted with MAOI drug therapy to alleviate alcohol-related brain injury. Further examination of MAOIs to reduce alcohol use disorder-related brain injury could provide pivotal insight to future pharmacotherapeutic opportunities.


Assuntos
Consumo Excessivo de Bebidas Alcoólicas/enzimologia , Encefalopatias/prevenção & controle , Depressores do Sistema Nervoso Central/toxicidade , Etanol/toxicidade , Inibidores da Monoaminoxidase/uso terapêutico , Monoaminoxidase/genética , Transdução de Sinais/efeitos dos fármacos , Transativadores/efeitos dos fármacos , Transativadores/genética , Animais , Encefalopatias/induzido quimicamente , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Caspase 3/metabolismo , Morte Celular , Depressores do Sistema Nervoso Central/administração & dosagem , Depressores do Sistema Nervoso Central/antagonistas & inibidores , Etanol/administração & dosagem , Etanol/antagonistas & inibidores , Masculino , Fármacos Neuroprotetores/farmacologia , Síndromes Neurotóxicas/prevenção & controle , Estresse Oxidativo/efeitos dos fármacos , Medição da Dor/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
7.
Neuropsychopharmacology ; 40(6): 1373-82, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25502632

RESUMO

The biochemical pathways underlying major depressive disorder (MDD) and chronic stress are not well understood. However, it has been reported that monoamine oxidase A (MAO A, a major neurotransmitter-degrading enzyme) is significantly increased in the brains of human subjects affected with MDD and rats exposed to chronic social defeat (CSD) stress, which is used to model depression. In the current study, we compared the protein levels of a MAO A-transcriptional activator, Kruppel-like factor 11 (KLF11 , also recognized as transforming growth factor-beta-inducible early gene 2) between the brains of 18 human subjects with MDD and 18 control subjects. We found that, indeed, the expression of KLF11 is increased by 36% (p<0.02) in the postmortem prefrontal cortex of human subjects with MDD compared with controls. We also observed a positive correlation between KLF11 levels and those of its target gene, MAO A, both in association with MDD. KLF11 protein expression was also increased by 44% (p<0.02) in the frontal cortex of KLF11 wild-type mice (Klf11(+/+)) vs Klf11(-/-) when both exposed to CSD stress. In contrast, locomotor activities, central box duration and sucrose preference were significantly reduced in the stressed Klf11(+/+) mice, suggesting that Klf11(+/+) mice are more severely affected by the stress model compared with Klf11(-/-) mice. These results serve to assign an important role of KLF11 in upregulating MAO A in MDD and chronic social stress, suggesting that inhibition of the pathways regulated by this transcription factor may aid in the therapeutics of neuropsychiatric illnesses. Thus, the new knowledge derived from the current study extends our understanding of transcriptional mechanisms that are operational in the pathophysiology of common human diseases and thus bears significant biomedical relevance.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Proteínas de Ligação a DNA/metabolismo , Transtorno Depressivo Maior/metabolismo , Lobo Frontal/metabolismo , Monoaminoxidase/metabolismo , Proteínas Repressoras/metabolismo , Estresse Psicológico/metabolismo , Fatores de Transcrição/metabolismo , Animais , Proteínas Reguladoras de Apoptose , Doença Crônica , Proteínas de Ligação a DNA/genética , Modelos Animais de Doenças , Dominação-Subordinação , Feminino , Humanos , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Atividade Motora/fisiologia , Índice de Gravidade de Doença , Fatores de Transcrição/genética , Regulação para Cima
8.
Neurotox Res ; 28(1): 18-31, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25739536

RESUMO

Major depressive disorder and alcoholism are significant health burdens that can affect executive functioning, cognitive ability, job responsibilities, and personal relationships. Studies in animal models related to depression or alcoholism reveal that the expression of Krüppel-like factor 11 (KLF11, also called TIEG2) is elevated in frontal cortex, which suggests that KLF11 may play a role in stress- or ethanol-induced psychiatric conditions. KLF11 is a transcriptional activator of monoamine oxidase A and B, but also serves other functions in cell cycle regulation and apoptotic cell death. In the present study, immunohistochemistry was used to quantify intensity of nuclear KLF11, combined with an unbiased stereological approach to assess nuclei in fronto-limbic, limbic, and other brain regions of rats exposed chronically to social defeat or ethanol. KLF11 immunoreactivity was increased significantly in the medial prefrontal cortex, frontal cortex, and hippocampus of both stressed rats and rats fed ethanol. However, expression of KLF11 protein was not significantly affected in the thalamus, hypothalamus, or amygdala in either treatment group compared to respective control rats. Triple-label immunofluorescence revealed that KLF11 protein was localized in nuclei of neurons and astrocytes. KLF11 was also co-localized with the immunoreactivity of cleaved caspase-3. In addition, Western blot analysis revealed a significant reduction in anti-apoptotic protein, Bcl-xL, but an increase of caspase-3 expression in the frontal cortex of ethanol-treated rats compared to ethanol-preferring controls. Thus, KLF11 protein is up-regulated following chronic exposure to stress or ethanol in a region-specific manner and may contribute to pro-apoptotic signaling in ethanol-treated rats. Further investigation into the KLF11 signaling cascade as a mechanism for neurotoxicity and cell death in depression and alcoholism may provide novel pharmacological targets to lessen brain damage and maximize neuroprotection in these disorders.


Assuntos
Apoptose , Encéfalo/metabolismo , Etanol/administração & dosagem , Estresse Psicológico/metabolismo , Transativadores/metabolismo , Animais , Apoptose/efeitos dos fármacos , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Encéfalo/efeitos dos fármacos , Caspase 3/metabolismo , Dominação-Subordinação , Etanol/farmacologia , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Masculino , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Ratos , Ratos Wistar , Proteína bcl-X/metabolismo
9.
Drug Discov Ther ; 6(3): 112-22, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22890201

RESUMO

Monoamine oxidases play an integral role in brain function. Both monoamine oxidase A (MAO-A) and monoamine oxidase B (MAO-B) regulate neurochemistry by degrading monoamine neurotransmitters (serotonin, dopamine, and norepinephrine). Any alteration in MAO levels can have devastating effects on the brain and behavior by lowering or raising neurotransmitter levels and producing toxic reactive oxygen species. In this review article, MAO is examined in terms of function and genetic organization, with special focus on recent discoveries related to the transcriptional regulation of MAO. In recent studies, transcriptional regulation involves a repressor protein, R1, for MAO-A and an activator protein, KLF11 (a Krüppel-like factor; also referred to as transforming growth factor-beta early inducible gene 2, TIEG2), for both MAO-A and MAO-B, by binding to Sp/KLF sites in the core promoters of MAO and regulating MAO gene expression. Furthermore, KLF11 may influence MAO-B expression and augment glyceraldehyde-3 phosphate dehydrogenase (GAPDH) to upregulate MAO-B transcription upon exposure to ethanol. Finally, we review recent progress in MAO research and highlight the roles that MAOs play in several psychiatric conditions, including chronic stress, major depressive disorder and alcohol dependence. Further research in this area is needed to better understand MAOs, their transcription factors and signaling pathways in psychiatric illnesses in order to develop new strategies for pharmacological advancement.


Assuntos
Alcoolismo/enzimologia , Transtorno Depressivo Maior/enzimologia , Monoaminoxidase/fisiologia , Alcoolismo/etiologia , Proteínas Reguladoras de Apoptose , Proteínas de Ciclo Celular/fisiologia , Transtorno Depressivo Maior/etiologia , Humanos , Monoaminoxidase/genética , Proteínas Repressoras/fisiologia , Estresse Psicológico/enzimologia , Transcrição Gênica
10.
Neuropsychopharmacology ; 36(10): 2139-48, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21654740

RESUMO

The novel transcriptional repressor protein, R1 (JPO2/CDCA7L/RAM2), inhibits monoamine oxidase A (MAO A) gene expression and influences cell proliferation and survival. MAO A is implicated in several neuropsychiatric illnesses and highly elevated in major depressive disorder (MDD); however, whether R1 is involved in these disorders is unknown. This study evaluates the role of R1 in depressed subjects either untreated or treated with antidepressant drugs. R1 protein levels were determined in the postmortem prefrontal cortex of 18 untreated MDD subjects and 12 medicated MDD subjects compared with 18 matched psychiatrically normal control subjects. Western blot analysis showed that R1 was significantly decreased by 37.5% (p<0.005) in untreated MDD subjects. The R1 level in medicated MDD subjects was also significantly lower (by 30%; p<0.05) compared with control subjects, but was not significantly different compared with untreated MDD subjects. Interestingly, the reduction in R1 was significantly correlated with an increase (approximately 40%; p<0.05) in MAO A protein levels within the MDD groups compared with controls. Consistent with the change in MAO A protein expression, the MAO A catalytic activity was significantly greater in both MDD groups compared with controls. These results suggest that reduced R1 may lead to elevated MAO A levels in untreated and treated MDD subjects; moreover, the reduction of R1 has been implicated in apoptotic cell death and apoptosis has also been observed in the brains of MDD subjects. Therefore, modulation of R1 levels may provide a new therapeutic target in the development of more effective strategies to treat MDD.


Assuntos
Transtorno Depressivo Maior/metabolismo , Monoaminoxidase/deficiência , Monoaminoxidase/genética , Proteínas Repressoras/antagonistas & inibidores , Apoptose/genética , Apoptose/fisiologia , Transtorno Depressivo Maior/enzimologia , Transtorno Depressivo Maior/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Monoaminoxidase/biossíntese , Proteínas Repressoras/fisiologia , Estudos Retrospectivos
11.
Neurotox Res ; 19(4): 511-8, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-20204567

RESUMO

Brain cell loss has been reported in subjects with alcoholism. However, the molecular mechanisms are unclear. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and monoamine oxidase B (MAO B) reportedly play a role in cellular dysfunction with regards to ethanol exposure. We have recently reported that GAPDH protein expression was increased in the brains of rats fed with ethanol. Furthermore, GAPDH interacts with the transcriptional activator, transforming growth factor-beta-inducible early gene 2 (TIEG2), to augment TIEG2-mediated MAO B activation, resulting in neuronal cell damage due to ethanol exposure. The current study investigates whether the TIEG2-MAO B cascade is also active in the brains of rats fed with ethanol. Ten ethanol-preferring rats were fed with a liquid diet containing ethanol, with increasing amounts of ethanol up to a final concentration of 6.4% representing a final diet containing 36% of calories for 28 days. Ten control rats were fed the liquid diet without ethanol. The expression of TIEG2 protein, MAO B mRNA levels, MAO B catalytic activity, and the levels of anti-apoptotic protein Bcl 2 and apoptotic protein caspase 3 were determined in the prefrontal cortex of the rats. Ethanol significantly increased protein levels of TIEG2, active caspase 3, MAO B mRNA and enzyme activity, but significantly decreased Bcl 2 protein expression compared to control rats. In summary, ethanol increases the TIEG2-MAO B brain cell death cascade in rat brains, suggesting that the TIEG2-MAO B pathway is a novel pathway for brain cell damage resulting from ethanol exposure, and may contribute to chronic alcohol-induced brain damage.


Assuntos
Consumo de Bebidas Alcoólicas/metabolismo , Etanol/administração & dosagem , Monoaminoxidase/biossíntese , Córtex Pré-Frontal/enzimologia , Transdução de Sinais/fisiologia , Transativadores/biossíntese , Consumo de Bebidas Alcoólicas/patologia , Animais , Morte Celular/efeitos dos fármacos , Morte Celular/fisiologia , Etanol/farmacologia , Masculino , Córtex Pré-Frontal/efeitos dos fármacos , Distribuição Aleatória , Ratos , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos , Transativadores/genética
12.
Front Neurosci ; 4: 180, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21103012

RESUMO

Stress detrimentally affects the brain and body and can lead to or be accompanied by depression. Although stress and depression may contribute to each other, the exact molecular mechanism underlying the effects is unclear. However, there is a correlation between stress and an increase in glucocorticoid secretion which causes a subsequent increase in monoamine oxidase (MAO) activity during stress. Consequently, MAO inhibitors have been used as traditional antidepressant drugs. Cellular treatment with the synthetic glucocorticoid, dexamethasone (a cellular stressor), has been reported to markedly increase both MAO A and MAO B catalytic activities, as well as apoptosis. This study compares the neuroprotective abilities of M30 (a new generation inhibitor of both MAO A and MAO B) with rasagiline (Azilect(®), another new MAO B inhibitor) and selegiline (Deprenyl(®), a traditional MAO B inhibitor) in the prevention of dexamethasone-induced brain cell death and MAO activity in human neuroblastoma cells, SH-SY5Y. M30 demonstrated the highest inhibitory effect on MAO A; however, M30 showed the lowest inhibitory effect on MAO B enzymatic activity in comparison to rasagiline and selegiline. Although, M30 exhibited the greatest neuroprotective effect by decreasing cell death rates and apoptotic DNA damage compared to rasagiline and selegiline, these neuroprotective effects of M30 were, overall, similar to rasagiline. Summarily, M30 has a generally greater impact on neuroprotection than the MAO B inhibitors, selegiline and rasagiline. Our results suggest that M30 may have great potential in alleviating disorders involving increases in both MAO A and MAO B, such as stress-induced disorders.

13.
Neurotox Res ; 15(3): 284-90, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19384601

RESUMO

Stress can affect the brain and lead to depression; however, the molecular pathogenesis is unclear. An association between stress and stress-induced hypersecretion of glucocorticoids occurs during stress. Dexamethasone (a synthetic glucocorticoid steroid) has been reported to induce apoptosis and increase the activity of monoamine oxidase (MAO) (Youdim et al. 1989). MAO is an enzyme for the degradation of aminergic neurotransmitters; dopamine, noradrenaline and serotonin and dietary amines and MAO inhibitors are classical antidepressant drugs. In this study, we have compared the ability of rasagiline (Azilect) and its main metabolite, R-aminoindan with selegiline (Deprenyl) in prevention of dexamethasone-induced brain cell death employing human neuroblastoma SH-SY5Y cells and glioblastoma 1242-MG cells. Dexamethasone reduced cell viability as measured by MTT test, but rasagiline, selegiline, and 1-R-aminoindan could significantly prevent dexamethasone-induced brain cell death. Among three drugs, rasagiline had the highest neuroprotective effect. Furthermore, the inhibitory effects of these drugs on MAO B catalytic activity and on apoptotic DNA damage (TUNEL staining) were examined. Rasagiline exhibited highest inhibition on MAO B enzymatic activity and prevention on DNA damage as compared to selegiline and 1-R-aminoindan. In summary, the greater neuroprotective effect of rasagiline may be associated with the combination of the parent drug and its metabolite 1-R-aminoindan.


Assuntos
Anti-Inflamatórios/toxicidade , Apoptose/efeitos dos fármacos , Dexametasona/toxicidade , Fármacos Neuroprotetores/farmacologia , Análise de Variância , Encéfalo/citologia , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Glioblastoma , Humanos , Marcação In Situ das Extremidades Cortadas/métodos , Indanos/farmacologia , Monoaminoxidase/metabolismo , Neuroblastoma , Selegilina/farmacologia , Sais de Tetrazólio , Tiazóis
14.
Drug Discov Ther ; 2(5): 289-295, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19946577

RESUMO

Alcohol use disorders are common in the world. However, the development of novel drugs to prevent alcohol-induced brain damage is based upon an improved neurobiological understanding on the cellular changes that take place in the brain. We previously reported that ethanol exposure lowered cell proliferation and increased cell apoptosis in all cell types, but affects brain cell lines the most, while ethanol and the anti-depressant drug deprenyl, an monoamine oxidase B (MAO B) inhibitor, exposure in unison increases cell viability. Here we investigated the molecular mechanism of the neuroprotective effect of deprenyl (0.25 nM) on ethanol (75 mM)-induced harmful effect. Transforming growth factor-beta-inducible early gene 2 (TIEG2) is an activator for MAO B. MAO B levels increase has been shown to contribute to neuronal cell death. This study uses the neuronal cell line to address whether ethanol induced cell death is through the activation of TIEG2-MAO B apoptotic pathway, and whether deprenyl protects cells from the effects of alcohol through the inhibition of this pathway. We have found that ethanol exposure increases the levels of mRNA and protein/catalytic activity for both TIEG2 and MAO B, while ethanol and deprenyl exposure in unison reduce the expression of both TIEG2 and MAO B, however it increases cell viability. Additionally, TIEG2-overexpressed cells display more cellular death-induced by ethanol than control cells. In summary, this study demonstrates the role of TIEG2 in ethanol induced cell death. The inhibition of the TIEG2-MAO B pathway may be one of the mechanisms for the neuroprotective effect of deprenyl.

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