Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 70
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Front Hum Neurosci ; 18: 1415904, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38873654

RESUMO

Noninvasive brain stimulation (NIBS) techniques, including transcranial direct current stimulation (tDCS) and transcranial random noise stimulation (tRNS), are emerging as promising tools for enhancing cognitive functions by modulating brain activity and enhancing cognitive functions. Despite their potential, the specific and combined effects of tDCS and tRNS on brain functions, especially regarding functional connectivity, cortical inhibition, and memory performance, are not well-understood. This study aims to explore the distinct and combined impacts of tDCS and tRNS on these neural and cognitive parameters. Using a within-subject design, ten participants underwent four stimulation conditions: sham, tDCS, tRNS, and combined tDCS + tRNS. We assessed the impact on resting-state functional connectivity, cortical inhibition via Cortical Silent Period (CSP), and visuospatial memory performance using the Corsi Block-tapping Test (CBT). Our results indicate that while tDCS appears to induce brain lateralization, tRNS has more generalized and dispersive effects. Interestingly, the combined application of tDCS and tRNS did not amplify these effects but rather suggested a non-synergistic interaction, possibly due to divergent mechanistic pathways, as observed across fMRI, CSP, and CBT measures. These findings illuminate the complex interplay between tDCS and tRNS, highlighting their non-additive effects when used concurrently and underscoring the necessity for further research to optimize their application for cognitive enhancement.

2.
Curr Issues Mol Biol ; 45(10): 8309-8320, 2023 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-37886967

RESUMO

Glioblastoma multiforme (GBM) is the most common and deadliest primary brain tumor in adults. Despite the advances in GBM treatment, outcomes remain poor, with a 2-year survival rate of less than 5%. Hyperbaric oxygen (HBO) therapy is an intermittent, high-concentration, short-term oxygen therapy used to increase cellular oxygen content. In this study, we evaluated the effects of HBO therapy, alone or combined with other treatment modalities, on GBM in vitro and in vivo. In the in vitro analysis, we used a 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay to assess the effects of HBO therapy alone, a colony formation assay to analyze the effects of HBO therapy combined with radiotherapy and with temozolomide (TMZ), and a neurosphere assay to assess GBM stemness. In the in vivo analysis, we used immunohistochemical staining and in vivo bioluminescence imaging to assess GBM stemness and the therapeutic effect of HBO therapy alone or combined with TMZ or radiotherapy, respectively. HBO therapy did not affect GBM cell viability, but it did reduce the analyzed tumors' ability to form cancer stem cells. In addition, HBO therapy increased GBM sensitivity to TMZ and radiotherapy both in vitro and in vivo. HBO therapy did not enhance tumor growth and exhibited adjuvant effects to chemotherapy and radiotherapy through inhibiting GBM stemness. In conclusion, HBO therapy shows promise as an adjuvant treatment for GBM by reducing cancer stem cell formation and enhancing sensitivity to chemotherapy and radiotherapy.

3.
Neuropharmacology ; 214: 109140, 2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35613660

RESUMO

Anxiety is characterized by feelings of tension and worry even in the absence of threatening stimulus. Pathological condition of anxiety elicits defensive behavior and aversive reaction ultimately impacting individuals and society. The gut microbiota has been shown to contribute to the modulation of anxiety-like behavior in rodents through the gut-brain axis. Several studies observed that germ-free (GF) and the broad spectrum of antibiotic cocktail (ABX)-treated rodents display lowered anxiety-like behavior. We speculate that gut microbial short-chain fatty acids (SCFA) modulate the innate anxiety response. Herein, we administered SCFA in the drinking water in adult mice treated with ABX to deplete the microbiota and tested their anxiety-like behavior. To further augment the innate fear response, we enhanced the aversive stimulus of the anxiety-like behavior tests. Strikingly, we found that the anxiety-like behavior in ABX mice was not altered when enhanced aversive stimulus, while control and ABX mice supplemented with SCFA displayed increased anxiety-like behavior. Vagus nerve serves as a promising signaling pathway in the gut-brain axis. We determined the role of vagus nerve by subdiaphragmatic vagotomy (SDV) in ABX mice supplemented with SCFA. We found that the restored anxiety-like behavior in ABX mice by SCFA was unaffected by SDV. These findings suggest that gut microbiota can regulate anxiety-like behavior through their fermentation products SCFA.


Assuntos
Microbioma Gastrointestinal , Microbiota , Animais , Ansiedade/tratamento farmacológico , Transtornos de Ansiedade , Ácidos Graxos Voláteis/metabolismo , Camundongos , Camundongos Endogâmicos C57BL
4.
Healthcare (Basel) ; 9(9)2021 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-34574891

RESUMO

Drug-resistant epilepsy (DRE) is a chronic neurological disorder with somatic impacts and increased risk of metabolic comorbidities. Oxidative stress might play an important role in metabolic effects and as a regulator of seizure control, while coenzyme Q10 (CoQ10) could improve insulin sensitivity through antioxidant effects. We aimed to investigate the association between CoQ10 level and clinical outcome, represented by the seizure frequency and quality of life, in DRE patients. DRE patients (N = 33) had significantly higher serum insulin levels and lower scores on the physical domain of the World Health Organization Quality of Life questionnaire (WHOQoL) than gender-age matched controls. The serum CoQ10 level (2910.4 ± 1163.7 ng/mL) was much higher in DRE patients than the normal range. Moreover, the serum CoQ10 level was significantly correlated with the seizure frequency (r = -0.412, p = 0.037) and insulin level (r = 0.409, p = 0.038). Based on stratification by insulin resistance (HOMA-IR > 2.4), the subgroup analysis showed that patients with a greater HOMA-IR had higher CoQ10 levels and lower seizure frequency, and had a significantly worse quality of life. In summary, CoQ10 could be a mediator involved in the mechanism of epilepsy and serve as a biomarker of the clinical outcome in DER patients.

5.
Biomedicines ; 9(7)2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-34356837

RESUMO

After stroke, dynamic changes take place from necrotic-apoptotic continuum, inflammatory response to poststroke neurogenesis, and remodeling of the network. These changes and baseline brain pathology such as small vessel disease (SVD) and amyloid burden may be associated with the occurrence of early or late poststroke cognitive impairment (PSCI) or dementia (PSD), which affect not only stroke victims but also their families and even society. We reviewed the current concepts and understanding of the pathophysiology for PSCI/PSD and identified useful tools for the diagnosis and the prediction of PSCI in serological, CSF, and image characteristics. Then, we untangled their relationships with blood pressure (BP) and blood pressure variability (BPV), important but often overlooked risk factors for PSCI/PSD. Finally, we provided evidence for the modifying effects of BP and BPV on PSCI as well as pharmacological and non-pharmacological interventions and life style modification for PSCI/PSD prevention and treatment.

6.
Nutrients ; 12(8)2020 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-32784611

RESUMO

Observational studies have investigated the potential modulatory effect of neuronal excitability by vitamins in epilepsy. We aimed to investigate whether the addition of multivitamin therapy (B6/B9, D, E and Q) to regular antiepileptic drug therapy could ameliorate seizures in patients with refractory focal epilepsy. We conducted a prospective cohort open study to investigate the effect and tolerability of add-on multivitamin therapy (daily dose: B6 100 mg, B9 5 mg, D 1000 IU, E 400 IU and coenzyme Q10 100 mg) in patients with intractable focal epilepsy. All patients had effect and safety assessments at baseline and after one, three and six months of the supplementation. Thirty patients (11 men and 19 women) with a mean age of 42.37 ± 9.40 years were recruited and four patients discontinued. The seizure frequency significantly decreased after the six-month supplementation (9.04 ± 18.16/month and 2.06 ± 3.89/month, p = 0.045). At the final visit, 62.5% of the patients showed a ≥50% reduction in seizure frequency, and 12.5% were seizure-free. As to safety and tolerability, most patients did not experience significant adverse events, although three patients reported seizure worsening. In conclusion, this pilot study demonstrated the therapeutic potential and essentially good tolerability of add-on multivitamin therapy in patients with refractory focal epilepsy.


Assuntos
Anticonvulsivantes/administração & dosagem , Epilepsia Resistente a Medicamentos/tratamento farmacológico , Epilepsias Parciais/tratamento farmacológico , Vitaminas/administração & dosagem , Adulto , Quimioterapia Combinada , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Resultado do Tratamento
7.
Neuropharmacology ; 123: 175-185, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28601397

RESUMO

Activation of PI3K/Akt signaling, leading to upregulation of nitric oxide synthase II (NOS II)/peroxynitrite cascade in the rostral ventrolateral medulla (RVLM), the brain stem site that maintains blood pressure and sympathetic vasomotor tone, underpins cardiovascular depression induced by the organophosphate pesticide mevinphos. By exhibiting dual-specificity protein- and lipid-phosphatase activity, phosphatase and tensin homolog (PTEN) directly antagonizes the PI3K/Akt signaling by dephosphorylation of phosphatidylinositol-3,4,5-trisphosphate, the lipid product of PI3K. Based on the guiding hypothesis that PTEN may sustain brain stem cardiovascular regulation during mevinphos intoxication as a negative regulator of PI3K/Akt signaling in the RVLM, we aimed in this study to clarify the mechanistic role of PTEN in mevinphos-induced circulatory depression. Microinjection bilaterally of mevinphos (10 nmol) into the RVLM of anesthetized Sprague-Dawley rats induced a progressive hypotension and a decrease in baroreflex-mediated sympathetic vasomotor tone. There was progressive augmentation in PTEN activity as reflected by a decrease in the oxidized form of PTEN in the RVLM during mevinhpos intoxication, without significant changes in the mRNA or protein level of PTEN. Loss-of-function manipulations of PTEN in the RVLM by immunoneutralization, pharmacological blockade or siRNA pretreatment significantly potentiated the increase in Akt activity or NOS II/peroxynitrite cascade in the RVLM, enhanced the elicited hypotension and exacerbated the already reduced baroreflex-mediated sympathetic vasomotor tone. We conclude that augmented PTEN activity via a decrease of its oxidized form in the RVLM sustains brain stem cardiovascular regulation during mevinphos intoxication via downregulation of the NOS II/peroxynitrite cascade as a negative regulator of PI3K/Akt signaling.


Assuntos
Bulbo/efeitos dos fármacos , Bulbo/metabolismo , Mevinfós/toxicidade , PTEN Fosfo-Hidrolase/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Barorreflexo/efeitos dos fármacos , Barorreflexo/fisiologia , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Fármacos Cardiovasculares/toxicidade , Frequência Cardíaca/efeitos dos fármacos , Frequência Cardíaca/fisiologia , Masculino , Óxido Nítrico Sintase Tipo I/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Oxirredução , PTEN Fosfo-Hidrolase/química , PTEN Fosfo-Hidrolase/genética , Ácido Peroxinitroso/metabolismo , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley
8.
J Biomed Sci ; 23(1): 65, 2016 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-27658615

RESUMO

BACKGROUND: Small ubiquitin-related modifier (SUMO) is a group of proteins that participates in post-translational modifications. One known SUMO target is the transcription factor nuclear factor-kB (NF-kB) that plays a pivotal role in many disease processes; sumoylation inactivates NF-kB by conjugation with inhibitors of NF-kB (IkB). Our laboratory demonstrated previously that transcriptional upregulation of nitric oxide synthase II (NOS II) by NF-kB, leading to nitrosative stress by the formation of peroxynitrite in the rostral ventrolateral medulla (RVLM), underpins the defunct brain stem cardiovascular regulation that precedes brain death. Based on an experimental endotoxemia model, this study evaluated the hypothesis that sumoylation plays a pro-life role in brain death by interacting with the NF-kB/NOS II/peroxynitrite signaling pathway in the RVLM. RESULTS: In Sprague-Dawley rats, intravenous administration of Escherichia coli lipopolysaccharide (LPS; 10 mg kg-1) elicited an augmentation of SUMO-1 and ubiquitin-conjugase 9 (Ubc9) mRNA or protein levels, alongside SUMO-1-conjugated proteins in the RVLM. Immunoneutralization of SUMO-1 or Ubc9 in the RVLM significantly potentiated the already diminished sumoylation of IkBα and intensified NF-kB activation and NOS II/peroxynitrite expression in this brain stem substrate, together with exacerbated fatality, cardiovascular depression and reduction of an experimental index of a life-and-death signal detected from arterial pressure that disappears in comatose patients signifying failure of brain stem cardiovascular regulation before brain death. CONCLUSION: We conclude that sumoylation of IkB in the RVLM ameliorates the defunct brain stem cardiovascular regulation that underpins brain death in our experimental endotoxemia modal by reducing nitrosative stress via inhibition of IkB degradation that diminishes the induction of the NF-kB/NOS II/peroxynitrite signaling cascade.

9.
Oncotarget ; 7(41): 67150-67165, 2016 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-27564102

RESUMO

BACKGROUND: The aim of this study was to investigate the effects of the angiotensin II/ angiotensin II type I receptor (AT1R) and angiotensin II type II receptor (AT2R) signaling pathway in esophageal squamous cell carcinoma (ESCC). METHODS: Immunohistochemistry was performed to evaluate the expression levels of AT1R and AT2R in tissues from 152 surgically resected ESCC patients, and those expression levels were then correlated with treatment outcomes. The angiotensin II/AT1R/AT2R signaling pathway and its biological effects in the context of ESCC were investigated in vitro and in vivo. RESULTS: In human samples, AT1R overexpression was univariately associated with inferior overall survival and remained multivariately independent (hazard ratio=1.812). In vitro, angiotensin II stimulated the growth of ESCC cells in a dose-dependent manner. Treatment with irbesartan or AT1R-RNAi knockdown but not treatment with PD123319 significantly decreased the level of angiotensin II-induced ESCC cell proliferation. Angiotensin II also caused mTOR activation in a dose-dependent manner, and everolimus or mTOR-RNAi knockdown significantly suppressed the level of angiotensin II-induced ESCC cell proliferation. Furthermore, AT1R-RNAi knockdown suppressed the activation of mTOR. Clinically, AT1R expression was also correlated with phosphorylated mTOR expression. In a xenograft model, local angiotensin II injection enhanced tumor growth, and this effect could be decreased by treatment with irbesartan or everolimus. In a 4-NQO-induced-ESCC murine model, irbesartan significantly decreased the incidence of esophageal tumor. CONCLUSIONS: These findings suggest that AT1R overexpression is an independent adverse prognosticator for patients with ESCC and that angiotensin II/AT1R signaling stimulates ESCC growth, in part through mTOR activation.


Assuntos
Biomarcadores Tumorais/análise , Carcinoma de Células Escamosas/patologia , Neoplasias Esofágicas/patologia , Receptor Tipo 1 de Angiotensina/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Angiotensina II/metabolismo , Animais , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/mortalidade , Proliferação de Células , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/mortalidade , Carcinoma de Células Escamosas do Esôfago , Feminino , Xenoenxertos , Humanos , Estimativa de Kaplan-Meier , Masculino , Camundongos , Pessoa de Meia-Idade , Prognóstico
10.
Am J Physiol Heart Circ Physiol ; 311(3): H555-62, 2016 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-27371683

RESUMO

The sympathetic preganglionic neurons (SPN) in the thoracic spinal cord regulate vasomotor tone via norepinephrine released from sympathetic terminals and adrenal medulla. We assessed the hypothesis that nitric oxide synthase I (NOS I)- and NOS II-derived nitric oxide (NO) in the thoracic spinal cord differentially modulate sympathetic outflow and that the adrenal medulla may be involved in those modulatory actions. In Sprague-Dawley rats, NOS I immunoreactivity was distributed primarily in the perikaryon, proximal dendrites, or axons of SPN, and small clusters of NOS II immunoreactivity impinged mainly on the circumference of SPN. Intrathecal administration of 7-nitroindazole (7-NI), a specific NOS I antagonist, into the thoracic spinal cord significantly reduced arterial pressure, heart rate, and basal or baroreflex-mediated sympathetic vasomotor tone. On the other hand, intrathecal application of S-methylisothiourea (SMT), a specific NOS II antagonist, elevated arterial pressure with a transient reduction of heart rate, induced a surge of plasma norepinephrine, and reduced baroreflex-mediated but not basal sympathetic vasomotor tone. Bilateral adrenalectomy significantly exacerbated the cardiovascular responses to 7-NI but antagonized those to SMT. We conclude that both NOS I and NOS II are present in the thoracic spinal cord and are tonically active under physiological conditions. Furthermore, the endogenous NO generated by NOS I-containing SPN exerts a tonic excitatory action on vasomotor tone mediated by norepinephrine released from the adrenal medulla and sympathetic nerve terminals. On the other hand, NO derived from NOS II exerts a tonic inhibitory action on sympathetic outflow from the SPN that targets primarily the blood vessels.


Assuntos
Óxido Nítrico Sintase Tipo II/metabolismo , Óxido Nítrico Sintase Tipo I/metabolismo , Óxido Nítrico/metabolismo , Norepinefrina/metabolismo , Medula Espinal/metabolismo , Sistema Nervoso Simpático/metabolismo , Sistema Vasomotor/metabolismo , Medula Suprarrenal/metabolismo , Adrenalectomia , Animais , Axônios , Pressão Sanguínea/efeitos dos fármacos , Pressão Sanguínea/fisiologia , Vasos Sanguíneos/metabolismo , Vasos Sanguíneos/fisiologia , Dendritos , Inibidores Enzimáticos/farmacologia , Frequência Cardíaca/efeitos dos fármacos , Frequência Cardíaca/fisiologia , Indazóis/farmacologia , Isotiurônio/análogos & derivados , Isotiurônio/farmacologia , Masculino , Neurônios , Óxido Nítrico/biossíntese , Óxido Nítrico Sintase Tipo I/antagonistas & inibidores , Óxido Nítrico Sintase Tipo I/fisiologia , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Óxido Nítrico Sintase Tipo II/fisiologia , Ratos , Ratos Sprague-Dawley , Sistema Nervoso Simpático/efeitos dos fármacos , Sistema Nervoso Simpático/fisiologia , Vértebras Torácicas , Sistema Vasomotor/fisiologia
11.
Theranostics ; 6(6): 837-48, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27162554

RESUMO

Baroreflex is the physiological mechanism for the maintenance of blood pressure and heart rate. Impairment of baroreflex is not a disease per se. However, depending on severity, the eventuality of baroreflex dysfunction varies from inconvenience in daily existence to curtailment of mobility to death. Despite universal acceptance, neuronal traffic within the contemporary neural circuits during the execution of baroreflex has never been visualized. By enhancing signal detection and fine-tuning the scanning parameters, we have successfully implemented tractographic analysis of the medulla oblongata in mice that allowed for visualization of connectivity between key brain stem nuclei in the baroreflex circuits. When viewed in conjunction with radiotelemetric analysis of the baroreflex, we found that under pathophysiological conditions when the disrupted connectivity between key nuclei in the baroreflex circuits was reversible, the associated disease condition (e.g. neurogenic hypertension) was amenable to remedial measures. Nevertheless, fatality ensues under pathological conditions (e.g. hepatic encephalopathy) when the connectivity between key substrates in the baroreflex circuits was irreversibly severed. MRI/DTI also prompted partial re-wiring of the contemporary circuit for baroreflex-mediated sympathetic vasomotor tone, and unearthed an explanation for the time lapse between brain death and the inevitable asystole signifying cardiac death that follows.


Assuntos
Barorreflexo , Tronco Encefálico/diagnóstico por imagem , Tronco Encefálico/fisiologia , Imagem de Tensor de Difusão , Imageamento por Ressonância Magnética , Vias Neurais/diagnóstico por imagem , Animais , Camundongos , Telemetria
12.
Hypertension ; 67(6): 1298-308, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27045031

RESUMO

Loss of integrity and massive disruption of elastic fibers are key features of abdominal aortic aneurysm (AAA). Peroxisome proliferator-activated receptor γ (PPARγ) has been shown to attenuate AAA through inhibition of inflammation and proteolytic degradation. However, its involvement in elastogenesis during AAA remains unclear. PPARγ was highly expressed in human AAA within all vascular cells, including inflammatory cells and fibroblasts. In the aortas of transgenic mice expressing PPARγ at 25% normal levels (Pparg(C) (/-) mice), we observed the fragmentation of elastic fibers and reduced expression of vital elastic fiber components of elastin and fibulin-5. These were not observed in mice with 50% normal PPARγ expression (Pparg(+/-) mice). Infusion of a moderate dose of angiotensin II (500 ng/kg per minute) did not induce AAA but Pparg(+/-) aorta developed flattened elastic lamellae, whereas Pparg(C/-) aorta showed severe destruction of elastic fibers. After infusion of angiotensin II at 1000 ng/kg per minute, 73% of Pparg(C/-) mice developed atypical suprarenal aortic aneurysms: superior mesenteric arteries were dilated with extensive collagen deposition in adventitia and infiltrations of inflammatory cells. Although matrix metalloproteinase inhibition by doxycycline somewhat attenuated the dilation of aneurysm, it did not reduce the incidence nor elastic lamella deterioration in angiotensin II-infused Pparg(C/-) mice. Furthermore, PPARγ antagonism downregulated elastin and fibulin-5 in fibroblasts, but not in vascular smooth muscle cells. Chromatin immunoprecipitation assay demonstrated PPARγ binding in the genomic sequence of fibulin-5 in fibroblasts. Our results underscore the importance of PPARγ in AAA development though orchestrating proper elastogenesis and preserving elastic fiber integrity.


Assuntos
Aorta Abdominal/efeitos dos fármacos , Aneurisma da Aorta Abdominal/genética , Regulação da Expressão Gênica , Metaloproteinases da Matriz/metabolismo , PPAR gama/genética , Análise de Variância , Angiotensina II/farmacologia , Animais , Aorta Abdominal/metabolismo , Aorta Abdominal/patologia , Células Cultivadas , Modelos Animais de Doenças , Elastina/metabolismo , Humanos , Inflamação/metabolismo , Masculino , Camundongos , Camundongos Knockout , Pessoa de Meia-Idade , Músculo Liso Vascular/metabolismo
13.
Free Radic Biol Med ; 96: 116-29, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27107769

RESUMO

The advantage of using a cytoplasmic hybrid (cybrid) model to study the genetic effects of mitochondria is that the cells have the same nuclear genomic background. We previously demonstrated the independent role of mitochondria in the pathogenesis of insulin resistance (IR) and pro-inflammation in type 2 diabetes. In this study, we compared mitochondrial dynamics and related physiological functions between cybrid cells harboring diabetes-susceptible (B4) and diabetes-protective (D4) mitochondrial haplogroups, especially the responses before and after insulin stimulation. Cybrid B4 showed a more fragmented mitochondrial network, impaired mitochondrial biogenesis and bioenergetics, increased apoptosis and ineffective mitophagy and a low expression of fusion-related molecules. Upon insulin stimulation, increases in network formation, mitochondrial DNA (mtDNA) content, and ATP production were observed only in cybrid D4. Insulin promoted a pro-fusion dynamic status in both cybrids, but the trend was greater in cybrid D4. In cybrid B4, the imbalance of mitochondrial dynamics and impaired biogenesis and bioenergetics, and increased apoptosis were significantly improved in response to antioxidant treatment. We concluded that diabetes-susceptible mtDNA variants are themselves resistant to insulin.


Assuntos
Diabetes Mellitus Tipo 2/genética , Inflamação/genética , Mitocôndrias/genética , Estresse Oxidativo/genética , Trifosfato de Adenosina/metabolismo , Antioxidantes/uso terapêutico , Linhagem Celular Tumoral , DNA Mitocondrial/genética , DNA Mitocondrial/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patologia , Haplótipos/genética , Humanos , Inflamação/metabolismo , Inflamação/patologia , Insulina/metabolismo , Resistência à Insulina/genética , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Dinâmica Mitocondrial/genética , Osteossarcoma/genética , Osteossarcoma/metabolismo
14.
Thromb Haemost ; 114(6): 1230-40, 2015 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-26289958

RESUMO

Endothelial dysfunction leads to worse cognitive performance in Alzheimer's dementia (AD). While both cerebrovascular risk factors and endothelial dysfunction lead to activation of vascular cell adhesion molecule-1 (VCAM-1), intercellular adhesion molecule-1 (ICAM-1) and E-selectin, it is not known whether these biomarkers extend the diagnostic repertoire in reflecting intracerebral structural damage or cognitive performance. A total of 110 AD patients and 50 age-matched controls were enrolled. Plasma levels of VCAM-1, ICAM-1 and E-selectin were measured and correlated with the cognitive performance, white matter macro-structural changes, and major tract-specific fractional anisotropy quantification. The AD patients were further stratified by clinical dementia rating score (mild dementia, n=60; moderate-to-severe dementia, n=50). Compared with the controls, plasma levels of VCAM-1 (p< 0.001), ICAM-1 (p=0.028) and E-selectin (p=0.016) were significantly higher in the patients, but only VCAM-1 levels significantly reflected the severity of dementia (p< 0.001). In addition, only VCAM-1 levels showed an association with macro- and micro- white matter changes especially in the superior longitudinal fasciculus (p< 0.001), posterior thalamic radiation (p=0.002), stria terminalis (p=0.002) and corpus callosum (p=0.009), and were independent of, age and cortical volume. These tracts show significant association with MMSE, short term memory and visuospatial function. Meanwhile, while VCAM-1 level correlated significantly with short-term memory (p=0.026) and drawing (p=0.025) scores in the AD patients after adjusting for age and education, the significance disappeared after adjusting for global FA. Endothelial activation, especially VCAM-1, was of clinical significance in AD that reflects macro- and micro-structural changes and poor short term memory and visuospatial function.


Assuntos
Doença de Alzheimer/sangue , Molécula 1 de Adesão de Célula Vascular/sangue , Substância Branca/patologia , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/epidemiologia , Doença de Alzheimer/patologia , Apolipoproteína E4/genética , Estudos de Casos e Controles , Transtornos Cerebrovasculares/epidemiologia , Comorbidade , Diabetes Mellitus/epidemiologia , Imagem de Tensor de Difusão , Dislipidemias/epidemiologia , Selectina E/sangue , Endotélio Vascular/fisiopatologia , Feminino , Humanos , Hipertensão/epidemiologia , Molécula 1 de Adesão Intercelular/sangue , Imageamento por Ressonância Magnética , Masculino , Fatores de Risco , Índice de Gravidade de Doença , Fumar/epidemiologia
15.
J Biomed Sci ; 22: 46, 2015 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-26100815

RESUMO

BACKGROUND: Neuroinflammation with activation of microglia and production of proinflammatory cytokines in the brain plays an active role in epileptic disorders. Brain oxidative stress has also been implicated in the pathogenesis of epilepsy. Damage in the hippocampus is associated with temporal lobe epilepsy, a common form of epilepsy in human. Peripheral inflammation may exacerbate neuroinflammation and brain oxidative stress. This study examined the impact of peripheral inflammation on seizure susceptibility and the involvement of neuroinflammation and oxidative stress in the hippocampus. RESULTS: In male, adult Sprague-Dawley rats, peripheral inflammation was induced by the infusion of Escherichia coli lipopolysaccharide (LPS, 2.5 mg/kg/day) into the peritoneal cavity for 7 days via an osmotic minipump. Pharmacological agents were delivered via intracerebroventricular (i.c.v.) infusion with an osmotic minipump. The level of cytokine in plasma or hippocampus was analyzed by ELISA. Redox-related protein expression in hippocampus was evaluated by Western blot. Seizure susceptibility was tested by intraperitoneal (i.p.) injection of kainic acid (KA, 10 mg/kg). We found that i.p. infusion of LPS for 7 days induced peripheral inflammation characterized by the increases in plasma levels of interleukin-1ß (IL-1ß), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α). This is associated with a significant increase in number of the activated microglia (Iba-1(+) cells), enhanced production of proinflammatory cytokines (including IL-1ß, IL-6 and TNF-α), and tissue oxidative stress (upregulations of the NADPH oxidase subunits) in the hippocampus. These cellular and molecular responses to peripheral inflammation were notably blunted by i.c.v. infusion of a cycloxygenase-2 inhibitor, NS398 (5 µg/µl/h). The i.c.v. infusion of tempol (2.5 µg/µl/h), a reactive oxygen species scavenger, protected the hippocampus from oxidative damage with no apparent effect on microglia activation or cytokine production after peripheral inflammation. In the KA-induced seizure model, i.c.v. infusion of both NS398 and tempol ameliorated the increase in seizure susceptibility in animals succumbed to the LPS-induced peripheral inflammation. CONCLUSIONS: Together these results indicated that LPS-induced peripheral inflammation evoked neuroinflammation and the subsequent oxidative stress in the hippocampus, resulting in the increase in KA-induced seizure susceptibility. Moreover, protection from neuroinflammation and oxidative stress in the hippocampus exerted beneficial effect on seizure susceptibility following peripheral inflammation.


Assuntos
Epilepsia do Lobo Temporal/tratamento farmacológico , Hipocampo/efeitos dos fármacos , Inflamação/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Convulsões/tratamento farmacológico , Animais , Óxidos N-Cíclicos/administração & dosagem , Epilepsia do Lobo Temporal/sangue , Epilepsia do Lobo Temporal/induzido quimicamente , Epilepsia do Lobo Temporal/fisiopatologia , Hipocampo/patologia , Humanos , Inflamação/sangue , Inflamação/induzido quimicamente , Inflamação/fisiopatologia , Interleucina-1beta/sangue , Interleucina-6/sangue , Ácido Caínico/toxicidade , Lipopolissacarídeos/toxicidade , Microglia/efeitos dos fármacos , Microglia/patologia , Nitrobenzenos/administração & dosagem , Ratos , Convulsões/sangue , Convulsões/induzido quimicamente , Convulsões/fisiopatologia , Marcadores de Spin , Sulfonamidas/administração & dosagem , Fator de Necrose Tumoral alfa/sangue
16.
Mol Cancer ; 14: 83, 2015 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-25889801

RESUMO

BACKGROUND: Head and neck cancer (HNC) is a highly invasive cancer. Aurora-A has been reported for a number of malignancies. However, the identity of downstream effectors responsible for its aggressive phenotype in HNC remains underinvestigated. METHODS: The mRNA and protein expression levels of Aurora-A and FLJ10540 were assessed in HNC specimens and cell lines using RT-qPCR, western blot, Oncomine, and microarray database analysis. The downstream molecular mechanisms of Aurora-A were confirmed by RT-qPCR, western blot, luciferase reporter, confocal microscopy analyses, immunoprecipitation, colony formation, cell viability, and xenograft model. Cellular functions in response to Aurora-A-modulated downstream targets such as FLJ10540 and MMPs were examined in vitro and in vivo, including cell growth, motility and chemosensitivity. Aurora-A/FLJ10540/MMPs expression was determined in cancer and adjacent normal tissues from HNC patients by immunohistochemistry approach. RESULTS: In the current study, Aurora-A exhibited similar gene expression profiles with FLJ10540 by using accessibly public microarray and Oncomine database analysis, raising the possibility that these molecules might coordinately participate in cancer progression and metastasis of HNC. These two molecules connection were also examined in cell lines and tissues of HNC. Aurora-A overexpression could not only bind to the promoter of FLJ10540 to induce FLJ10540 expression, but also increase both mRNA and protein levels of MMP-7 and MMP-10 in HNC cells. Conversely, depletion of Aurora-A expression by using siRNA or Aurora-A kinase inhibitor, MLN8237, suppressed FLJ10540, MMP-7 and MMP-10 mRNA and protein expressions in vitro and in vivo. In addition, the FLJ10540-PI3K complex was destroyed by inhibition the Aurora-A kinase activity. Forced overexpression of FLJ10540 in Aurora-A-depleted or in MLN8237-treated HNC cells attenuated the effect on cytotoxicity to cisplatin. Elevated Aurora-A expression in HNC cells led to the characteristics of more aggressive malignancy, including enhanced chemoresistance and increased the abilities of proliferation, migration and invasion, which was required for FLJ10540/MMP-7 or FLJ10540/MMP-10 expressions. Finally, immunohistochemical analysis of human HNC specimens showed a significant positively correlation among Aurora-A, FLJ10540, MMP-7 and MMP-10 expressions. CONCLUSION: Together, our findings define a novel mechanism by which Aurora-A promotes cell malignancy, with potential implications for understanding the clinical action of Aurora-A.


Assuntos
Aurora Quinase A/genética , Proteínas de Ciclo Celular/genética , Neoplasias de Cabeça e Pescoço/genética , Proteínas Nucleares/genética , Transdução de Sinais/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Sobrevivência Celular/genética , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Metaloproteinases da Matriz/genética , Invasividade Neoplásica/genética , Fosfatidilinositol 3-Quinases/genética , RNA Mensageiro/genética
18.
Surgery ; 157(3): 570-80, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25726316

RESUMO

BACKGROUND: Although marked improvements have been made in surgical technique and chemoradiotherapy, the prognosis for patients with esophageal squamous cell carcinoma (ESCC) is still unsatisfactory. The mammalian target of rapamycin (mTOR) and its downstream signaling, p70 ribosomal S6 protein kinase (p70S6K) and eukaryotic translation initiation factor 4E (eIF4E)-binding protein 1 (4E-BP1), seem to play central roles in the regulation of cancer cell proliferation and survival. The significance of mTOR and its downstream targets, p70S6K and 4E-BP1, on the prognosis of ESCC remains uncertain, but this pathway is of particular concern because effective inhibitors are already available. METHODS: Immunohistochemistry performed to evaluate the expression of phosphorylated mTOR (p-mTOR), phosphorylated p70S6K (p-p70S6K), phosphorylated 4E-binding protein 1 (p-4E-BP1), and Ki-67 using 105 surgically resected ESCC correlated with treatment outcome. The effect of the mTOR signaling pathway inhibitor everolimus on ESCC cell lines were investigated in vitro by the 3-(4.5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and in vivo by a nude mouse xenograft model. RESULTS: Univariate analysis showed that p-mTOR overexpression (P = .022), p-p70S6K overexpression (P = .002), and Ki-67 labeling index >50% (P = .045) were associated with inferior overall survival (OS). In a multivariate comparison, p-p70S6K overexpression (P = .001; hazard ratio, 2.247) remained independently associated with worse OS. In cell lines and the xenograft model, everolimus significantly inhibited ESCC growth. CONCLUSION: Overexpression of p-p70S6K is associated independently with a poor prognosis among patients with ESCC. The mTOR signaling pathway inhibitor everolimus can inhibit ESCC growth in vitro and in vivo. Our findings suggest that inhibition of mTOR signaling pathway may be a promising novel target for ESCC.


Assuntos
Carcinoma de Células Escamosas/mortalidade , Neoplasias Esofágicas/mortalidade , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Neoplasias Esofágicas/metabolismo , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago , Everolimo , Feminino , Humanos , Masculino , Camundongos , Pessoa de Meia-Idade , Fosforilação , Prognóstico , Transdução de Sinais/fisiologia , Sirolimo/análogos & derivados , Sirolimo/farmacologia , Serina-Treonina Quinases TOR/fisiologia , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Biochem Pharmacol ; 93(1): 34-41, 2015 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-25449601

RESUMO

FLJ10540, originally identified as a microtubule-associated protein, induces cell proliferation and migration during tumorigenesis via the formation of FLJ10540-PI3K complex and enhancement of PI3K kinase activity. Interestingly, activation of PI3K/Akt cascade, leading to upregulation of nitric oxide synthase II (NOS II)/peroxynitrite signaling in the rostral ventrolateral medulla (RVLM), the brain stem site that maintains blood pressure and sympathetic vasomotor tone, mediates the impairment of brain stem cardiovascular regulation induced by the pesticide mevinphos. We evaluated the hypothesis that upregulation of FLJ10540 in the RVLM is upstream to this repertoire of signaling cascade that underpins mevinphos-induced circulatory depression. Microinjection bilaterally of mevinphos (10nmol) into the RVLM of anesthetized Sprague-Dawley rats induced a progressive hypotension that was accompanied by an increase (Phase I), followed by a decrease (Phase II) of an experimental index for baroreflex-mediated sympathetic vasomotor tone. There was augmentation in FLJ10540 mRNA in the RVLM or FLJ10540 protein in RVLM neurons, both of which were causally and temporally related to an augmentation of binding between the catalytic subunit (p110) and regulatory subunit (p85) of PI3K, phosphorylation of Akt at Thr308 site, and NOS II, superoxide or peroxynitrite level in the RVLM. Immunoneutralization of FJL10540 in the RVLM significantly antagonized those biochemical changes, and blunted the progressive hypotension and the reduced baroreflex-mediated sympathetic vasomotor tone during mevinphos intoxication. We conclude that upregulation of FLJ10540 in the RVLM elicits impairment of brain stem cardiovascular regulation that underpins circulatory depression during mevinphos intoxication via activation of PI3K/Akt/NOS II/peroxynitrite signaling cascade in the RVLM.


Assuntos
Fenômenos Fisiológicos Cardiovasculares , Proteínas de Ciclo Celular/biossíntese , Bulbo/metabolismo , Mevinfós/toxicidade , Proteínas Nucleares/biossíntese , Fosfatidilinositol 3-Quinases/biossíntese , Regulação para Cima/fisiologia , Animais , Tronco Encefálico/efeitos dos fármacos , Tronco Encefálico/metabolismo , Fenômenos Fisiológicos Cardiovasculares/efeitos dos fármacos , Masculino , Bulbo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Regulação para Cima/efeitos dos fármacos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...