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1.
World J Stem Cells ; 16(6): 708-727, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38948096

RESUMO

BACKGROUND: Pelvic organ prolapse (POP) involves pelvic organ herniation into the vagina due to pelvic floor tissue laxity, and vaginal structure is an essential factor. In POP, the vaginal walls exhibit abnormal collagen distribution and decreased fibroblast levels and functions. The intricate etiology of POP and the prohibition of transvaginal meshes in pelvic reconstruction surgery present challenges in targeted therapy development. Human umbilical cord mesenchymal stromal cells (hucMSCs) present limitations, but their exosomes (hucMSC-Exo) are promising therapeutic tools for promoting fibroblast proliferation and extracellular matrix remodeling. AIM: To investigate the effects of hucMSC-Exo on the functions of primary vaginal fibroblasts and to elucidate the underlying mechanism involved. METHODS: Human vaginal wall collagen content was assessed by Masson's trichrome and Sirius blue staining. Gene expression differences in fibroblasts from patients with and without POP were assessed via RNA sequencing (RNA-seq). The effects of hucMSC-Exo on fibroblasts were determined via functional experiments in vitro. RNA-seq data from fibroblasts exposed to hucMSC-Exo and microRNA (miRNA) sequencing data from hucMSC-Exo were jointly analyzed to identify effective molecules. RESULTS: In POP, the vaginal wall exhibited abnormal collagen distribution and reduced fibroblast 1 quality and quantity. Treatment with 4 or 6 µg/mL hucMSC-Exo suppressed inflammation in POP group fibroblasts, stimulated primary fibroblast growth, and elevated collagen I (Col1) production in vitro. High-throughput RNA-seq of fibroblasts treated with hucMSC-Exo and miRNA sequencing of hucMSC-Exo revealed that abundant exosomal miRNAs downregulated matrix metalloproteinase 11 (MMP11) expression. CONCLUSION: HucMSC-Exo normalized the growth and function of primary fibroblasts from patients with POP by promoting cell growth and Col1 expression in vitro. Abundant miRNAs in hucMSC-Exo targeted and downregulated MMP11 expression. HucMSC-Exo-based therapy may be ideal for safely and effectively treating POP.

2.
Oncol Rep ; 43(2): 447-460, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31894279

RESUMO

Endometrial cancer (EC) is a common form of cancer in women. Metastasis is the main cause of EC treatment failure. Eukaryotic translation initiation factor 4E (eIF4E) is an oncogene that is overexpressed in a variety of malignancies and their distant metastases. The present study analyzed microarray data from the Oncomine database and revealed that high eIF4E expression was associated with poor prognosis and high pathological grade of EC. The expression of eIF4E was higher in EC tissues compared with in adjacent normal tissues. In addition, microRNA (miR)­320a and miR­340­5p expression levels were downregulated in EC tissues compared with those in adjacent normal tissues, which suggested that these microRNAs may serve as EC tumor suppressor genes. miR­320a and miR­340­5p could bind to the 3'­UTR of eIF4E mRNA, thus downregulating the expression of eIF4E and phosphorylated (p)­eIF4E in EC cells. Overexpression of miR­320a or miR­340­5p effectively suppressed HEC­1A cell migration and invasion. The downregulation of eIF4E and p­eIF4E following miR­320a or miR­340­5p transfection reduced the invasiveness and metastatic capability of EC cells in a manner associated with decreased expression of matrix metallopeptidase (MMP)­3 and MMP­9. In addition, one of the effects of transforming growth factor ß1 (TGF­ß1), which is to induce the phosphorylation of eIF4E, was suppressed by miR­320a and miR­340­5p overexpression. These two microRNAs also attenuated the features of TGF­ß1­induced epithelial­mesenchymal transition (EMT). In conclusion, the results of the present study demonstrated that eIF4E was upregulated in EC, whereas miR­320a and miR­340­5p were downregulated in EC compared with adjacent normal tissues. In vitro, miR­320a and miR­340­5p inhibited the migratory capability of EC cells by downregulating MMP­3 and MMP­9 and prevented TGF­ß1­induced EMT through p­eIF4E.


Assuntos
Neoplasias do Endométrio/patologia , Fator de Iniciação 4E em Eucariotos/genética , MicroRNAs/genética , Linhagem Celular Tumoral , Neoplasias do Endométrio/genética , Neoplasias do Endométrio/metabolismo , Transição Epitelial-Mesenquimal , Fator de Iniciação 4E em Eucariotos/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Gradação de Tumores , Metástase Neoplásica , Prognóstico , Análise de Sobrevida , Fator de Crescimento Transformador beta1/metabolismo
3.
Neurosurgery ; 86(4): 524-529, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-31432068

RESUMO

BACKGROUND: Several patient and disease characteristics are thought to influence DBS outcomes; however, most previous studies have focused on long-term outcomes with only a few addressing immediate postoperative course. OBJECTIVE: To evaluate predictors of immediate outcomes (postoperative confusion and length of postoperative hospitalization) following deep brain stimulation surgery (DBS) in Parkinson disease (PD) patients. METHODS: We conducted a retrospective study of PD patients who underwent DBS at our institution from 2006 to 2011. We computed the proportion of patients with postoperative confusion and those with postoperative hospitalization longer than 2 d. To look for associations, Fisher's exact tests were used for categorical predictors and logistic regression for continuous predictors. RESULTS: We identified 130 patients [71% male, mean age: 63 ± 9.1, mean PD duration: 10.7 ± 5.1]. There were 7 cases of postoperative confusion and 19 of prolonged postoperative hospitalization. Of the 48 patients with tremors, none had postoperative confusion, whereas 10.1% of patients without tremors had confusion (P = .0425). Also, 10.2% of patients with preoperative falls/balance-dysfunction had postoperative confusion, whereas only 1.6% of patients without falls/balance-dysfunction had postoperative confusion (P = .0575). For every one-unit increase in score on the preoperative on-UPDRS III/MDS-UPDRS III score, the odds of having postoperative confusion increased by 10% (P = .0420). The following factors were noninfluential: age, disease duration, dyskinesia, gait freezing, preoperative levodopa-equivalent dose, number of intraoperative microelectrode passes, and laterality/side of surgery. CONCLUSION: Absence of tremors and higher preoperative UPDRS III predicted postoperative confusion after DBS in PD patients. Clinicians' awareness of these predictors can guide their decision making regarding patient selection and surgical planning.


Assuntos
Estimulação Encefálica Profunda/efeitos adversos , Doença de Parkinson/terapia , Complicações Pós-Operatórias/etiologia , Idoso , Delírio/etiologia , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Núcleo Subtalâmico/fisiologia , Resultado do Tratamento
4.
Cell Death Dis ; 9(2): 179, 2018 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-29415992

RESUMO

The incidence and mortality of intrahepatic cholangiocarcinoma (ICC) are increasing worldwide in recent decades. Osteopontin (OPN) plays an important role in cancer metastasis, but its functional mechanism in ICC is not clear yet. In this study, we found that OPN level was elevated both in plasma and tumor tissues of ICC patients, which was closely related to a shorter overall survival (OS) and high probability of tumor relapse after curative resection. The gain- and loss-of-function studies determined that OPN could promote ICC growth and metastasis. OPN selectively interacted with ß-Catenin and knockdown of ß-Catenin abrogated the effects induced by OPN. OPN recruited MAPK1 and activated MEK-MAPK1 pathway to mediate the S675 phosphorylation of ß-Catenin and nucleus accumulation, which induced the activation of Wnt signaling. Moreover, a significant correlation between OPN and ß-Catenin was found in ICC tissues. OPN, ß-Catenin, and their combination were independent prognostic indicator for ICC patients. In conclusion, OPN promotes ICC progression through recruiting MAPK1 and activating the Wnt/ß-Catenin pathway and can serve as a novel prognostic marker and therapeutic target for ICC.


Assuntos
Neoplasias dos Ductos Biliares/metabolismo , Colangiocarcinoma/metabolismo , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Osteopontina/metabolismo , beta Catenina/metabolismo , Animais , Neoplasias dos Ductos Biliares/patologia , Estudos de Casos e Controles , Processos de Crescimento Celular/fisiologia , Linhagem Celular Tumoral , Movimento Celular/fisiologia , Colangiocarcinoma/patologia , Células HEK293 , Xenoenxertos , Humanos , Sistema de Sinalização das MAP Quinases , Camundongos , Camundongos Nus , Metástase Neoplásica , Osteopontina/biossíntese , Fosforilação , Prognóstico , Serina/metabolismo , Via de Sinalização Wnt
5.
Cancer Sci ; 109(3): 710-723, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29285854

RESUMO

In the hepatocellular carcinoma (HCC) microenvironment, chemokine receptors play a critical role in tumorigenesis and metastasis. Our previous studies have found that osteopontin (OPN) is a promoter for HCC metastasis. However, the role of chemokine receptors in OPN-induced HCC metastasis remains unclear. In this study, we demonstrate that OPN is dramatically elevated in HCC tissues with metastasis and that high expression of OPN correlates with poorer overall survival and higher recurrence rate. OPN upregulates chemokine receptor expression, migration, invasion and pulmonary metastasis in HCC. We find that C-C chemokine receptor type 1 (CCR1) and C-X-C chemokine receptor type 6 (CXCR6) are the most upregulated chemokine receptors induced by OPN. CCR1 knockdown results in reduction of migration, invasion and pulmonary metastasis induced by OPN in vitro and in vivo, whereas CXCR6 knockdown does not reverse OPN-promoted migration and invasion. Moreover, OPN upregulates the expression of CCR1 through activating phosphoinositide 3-kinase (PI3K)/AKT and hypoxia-inducible factor 1α (HIF-1α) in HCC cells. Furthermore, blockade of OPN-CCR1 axis with CCR1 antagonist significantly restrains the promoting effects of OPN on HCC progression and metastasis. In human HCC tissues, OPN expression shows significantly positive correlation with CCR1 expression, and the patients with high levels of both OPN and CCR1 have the most dismal prognosis. Collectively, our results indicate that the OPN-CCR1 axis in HCC is important for accelerating tumor metastasis and that CCR1 is a potential therapeutic target for controlling metastasis in HCC patients with high OPN.


Assuntos
Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/patologia , Osteopontina/genética , Osteopontina/metabolismo , Receptores CCR1/metabolismo , Regulação para Cima , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Feminino , Regulação Neoplásica da Expressão Gênica , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Masculino , Metástase Neoplásica , Prognóstico , Transdução de Sinais , Análise de Sobrevida
6.
Parkinsons Dis ; 2017: 5609163, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28852579

RESUMO

OBJECTIVE: The primary objective was to evaluate predictors of quality of life (QOL) and functional outcomes following deep brain stimulation (DBS) in Parkinson's disease (PD) patients. The secondary objective was to identify predictors of global improvement. METHODS: PD patients who underwent DBS at our Center from 2006 to 2011 were evaluated by chart review and email/phone survey. Postoperative UPDRS II and EQ-5D were analyzed using simple linear regression adjusting for preoperative score. For global outcomes, we utilized the Patient Global Impression of Change Scale (PGIS) and the Clinician Global Impression of Change Scale (CGIS). RESULTS: There were 130 patients in the dataset. Preoperative and postoperative UPDRS II and EQ-5D were available for 45 patients, PGIS for 67 patients, and CGIS for 116 patients. Patients with falls/postural instability had 6-month functional scores and 1-year QOL scores that were significantly worse than patients without falls/postural instability. For every 1-point increase in preoperative UPDRS III and for every 1-unit increase in body mass index (BMI), the 6-month functional scores significantly worsened. Patients with tremors, without dyskinesia, and without gait-freezing were more likely to have "much" or "very much" improved CGIS. CONCLUSIONS: Presence of postural instability, high BMI, and worse baseline motor scores were the greatest predictors of poorer functional and QOL outcomes after DBS.

7.
J Neurol Sci ; 379: 308-311, 2017 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-28716269

RESUMO

INTRODUCTION: Dopamine agonists are a mainstay of treatment for patients with Parkinson disease (PD). However, side effects limit their use, often necessitating dose change. Upon withdrawal, patients may experience dopamine agonist withdrawal syndrome (DAWS). To date, there is no established protocol for the prevention or treatment of DAWS. METHODS: We performed a retrospective chart review of PD patients who were taking a dopamine agonist. RESULTS: In our large cohort of 313 PD patients who were on a dopamine agonist, we found that 39.5% (n=124) had a change in their dose of medication for various reasons, including 102 patients who experienced a side effect on a dopamine agonist. Twenty out of 102 patients (19.6%) developed symptoms consistent with DAWS, whereas 1 out of 22 patients (4.5%) who had medication dose changed due to any other reason (e.g. dyskinesias, DBS surgery, decreased by another provider, etc.) developed symptoms consistent with DAWS. Our DAWS population had a shorter duration of PD, less exposure to a dopamine agonist, and was on a lower dose compared to those patients who did not develop DAWS. Agitation was the most common DAWS symptom reported in our cohort. Interestingly, in terms of developing DAWS, the prevalence of DAWS (19.0% vs 16.5%; p=0.76) between partial versus total discontinuation was not significantly different whether the dopamine agonist dose was decreased (21 patients) or completely stopped (103 patients). CONCLUSION: Contrary to previous reports, we have found that other side effects besides impulse control behavioral disorders also increase risk for developing DAWS. Furthermore, the prevalence of DAWS did not differ between partial versus total discontinuation of the dopamine agonist.


Assuntos
Agonistas de Dopamina/efeitos adversos , Doença de Parkinson/tratamento farmacológico , Síndrome de Abstinência a Substâncias/epidemiologia , Centros de Atenção Terciária , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ohio/epidemiologia , Prevalência , Estudos Retrospectivos , Fatores de Risco
8.
Clin Respir J ; 11(4): 470-480, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26257384

RESUMO

BACKGROUND: Adenosine monophosphate (AMP) may reflect airway inflammation and hyperresponsiveness, but relationship between AMP and histamine (His, a conventional stimulus) bronchial provocation test (BPT) in asthma is not fully elucidated. OBJECTIVES: To compare both BPTs and determine their utility in reflecting changes of asthmatic symptoms. METHODS: BPTs were performed in a cross-over fashion, at 2-4 day intervals. Cumulative doses eliciting 20% FEV1 fall (PD20 FEV1 ), diagnostic performance and adverse events (AEs) were compared. Patients with PD20 FEV1 lower than geometric mean were defined as responders, otherwise poor responders. Patients with uncontrolled and partly controlled asthma, who maintained their original inhaled corticosteroids therapy, underwent reassessment of airway responsiveness and asthmatic symptoms 3 and 6 months after. RESULTS: Nineteen uncontrolled, 22 partly controlled and 19 controlled asthmatic patients and 24 healthy subjects were recruited. Lower PD20 FEV1 geometric means were associated with poorer asthma control in His-BPT (0.424 µmol vs 1.684 µmol vs 3.757 µmol), but not AMP-BPT (11.810 µmol vs 7.781 µmol vs 10.220 µmol). Both BPTs yielded similar overall diagnostic performance in asthma (area under curve: 0.842 in AMP-BPT vs 0.850 in His-BPT). AEs, including wheezing and tachypnea, were similar and mild. Ten patients with uncontrolled and 10 partly controlled asthma were followed-up. At months 3 and 6, we documented an increase in PD20 FEV1 -AMP and PD20 FEV1 -His, which did not correlate with reduction asthmatic symptom scores. This overall applied in responders and poor responders of AMP-BPT and His-BPT. CONCLUSION: Despite higher screening capacity of well-controlled asthma, AMP-BPT confers similar diagnostic performance and safety with His-BPT. AMP-BPT might not preferentially reflect changes asthmatic symptoms.


Assuntos
Monofosfato de Adenosina/administração & dosagem , Asma/diagnóstico , Testes de Provocação Brônquica/métodos , Histamina/administração & dosagem , Monofosfato de Adenosina/efeitos adversos , Monofosfato de Adenosina/farmacologia , Administração por Inalação , Corticosteroides/administração & dosagem , Corticosteroides/uso terapêutico , Adulto , Asma/tratamento farmacológico , Asma/fisiopatologia , Hiper-Reatividade Brônquica/diagnóstico , Estudos Transversais , Feminino , Volume Expiratório Forçado/efeitos dos fármacos , Histamina/efeitos adversos , Histamina/farmacologia , Humanos , Masculino , Pessoa de Meia-Idade
9.
Am J Cancer Res ; 6(9): 1873-1889, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27725896

RESUMO

Interleukin-6 (IL-6), one of the most important inflammatory cytokines, plays a pivotal role in metastasis and stemness of solid tumors. However, the underlying mechanisms of IL-6 in HCC metastasis remain unclear. In the present study, we demonstrated that stemness and metastatic potential of HCC cells were significantly enhanced after IL-6 stimulation. IL-6 could induce expression of osteopontin (OPN), along with other stemness-related genes, including HIF1α, BMI1, and HEY1. Block of OPN induction could significantly abrogate the effect of IL-6 on stemness and metastasis of HCC cells. Furthermore, IL-6 level was positively correlated with OPN in HCC. Patients with high plasma IL-6 or OPN level had poorer prognosis. In multivariate analysis, IL-6 and OPN were demonstrated to be independent prognostic indicators for HCC patients, and their combination had a better prognostic performance than IL-6 or OPN alone. Collectively, our findings indicate that IL-6 could enhance stemness and promote metastasis of HCC via up-regulating OPN expression, which can be a potential therapeutic target for combating HCC metastasis, and the combination of IL-6 and OPN serves as a promising prognostic predictor for HCC.

10.
Diabetologia ; 59(7): 1372-1375, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27115412

RESUMO

Glucagon plays important roles in normal glucose homeostasis and in metabolic abnormalities, particularly diabetes. Glucagon excess, rather than insulin deficiency, is essential for the development of diabetes for several reasons. Glucagon increases hepatic glucose and ketone production, the catabolic features of insulin deficiency. Hyperglucagonaemia is present in every form of diabetes. Beta cell destruction in glucagon receptor null mice does not cause diabetes unless mice are administered adenovirus encoding the glucagon receptor. In rodent studies the glucagon suppressors leptin and glucagon receptor antibody suppressed all catabolic manifestations of diabetes during insulin deficiency. Insulin prevents hyperglycaemia; however, insulin monotherapy cannot cure diabetes such that non-diabetic glucose homeostasis is achieved. Glucose-responsive beta cells normally regulate alpha cells, and diminished insulin action on alpha cells will favour hypersecretion of glucagon by the alpha cells, thus altering the insulin:glucagon ratio. Treating diabetes by suppression of glucagon, with leptin or antibody against the glucagon receptor, normalised glucose level (without glycaemic volatility) and HbA1c. Glucagon suppression also improved insulin sensitivity and glucose tolerance. If these results can be translated to humans, suppression of glucagon action will represent a step forward in the treatment of diabetes. This review summarises a presentation given at the 'Novel data on glucagon' symposium at the 2015 annual meeting of the EASD. It is accompanied by two other reviews on topics from this symposium (by Mona Abraham and Tony Lam, DOI: 10.1007/s00125-016-3950-3 , and by Russell Miller and Morris Birnbaum, DOI: 10.1007/s00125-016-3955-y ) and an overview by the Session Chair, Isabel Valverde (DOI: 10.1007/s00125-016-3946-z ).


Assuntos
Diabetes Mellitus/metabolismo , Diabetes Mellitus/patologia , Glucagon/metabolismo , Animais , Hemoglobinas Glicadas/metabolismo , Humanos , Insulina/metabolismo , Camundongos
11.
Respir Care ; 59(7): 1071-7, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24129336

RESUMO

BACKGROUND: Vibration response imaging (VRI) is a novel imaging technique and little is known about its characteristics and diagnostic value in idiopathic pulmonary fibrosis (IPF). The aim of this study was to investigate the features of VRI in subjects with IPF. METHODS: We enrolled 23 subjects with IPF (42-74 y old) and 28 healthy subjects (42-72 y old). Subjects with IPF were diagnosed by lung biopsy and underwent VRI, spirometry, lung diffusion testing, and chest x-ray or computed tomography, which entailed assessment of the value of VRI indices. RESULTS: The total VRI score correlated statistically with single-breath carbon monoxide diffusing capacity percent predicted (r = -0.30, P = .04), but not with FVC percent predicted, FEV1 percent predicted, and FEV1/FVC (r = -0.27, -0.22, and 0.19; all P > .05). Compared with healthy subjects (17.9%), 20 subjects with IPF (86.96%, P < .01) presented with significantly increased crackles. The difference in quality lung data in all lung regions was unremarkable (all P > .05), except for the upper right and lower left lobes (P < .05). Overall, VRI parameters yielded acceptable assay sensitivity and specificity. Maximum energy frame was characterized by the highest diagnostic value (sensitivity, 1.00; specificity, 0.82), followed by presence of abundant crackles (sensitivity, 0.70; specificity, 0.96). Total VRI score was not a sensitive indicator of IPF, owing to low assay sensitivity (0.70) and specificity (0.64). CONCLUSIONS: VRI may be helpful to discriminate between IPF subjects and healthy individuals. Maximum energy frame and abundant crackles might serve as a diagnostic tool for IPF.


Assuntos
Diagnóstico por Imagem/métodos , Fibrose Pulmonar Idiopática/diagnóstico , Vibração , Adulto , Idoso , Feminino , Humanos , Fibrose Pulmonar Idiopática/complicações , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Valor Preditivo dos Testes , Testes de Função Respiratória , Sons Respiratórios/diagnóstico , Sons Respiratórios/etiologia
12.
J Neurotrauma ; 30(6): 427-33, 2013 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-23102374

RESUMO

To evaluate the hypothesis that calpain 1 knockdown would reduce pathological damage and functional deficits after spinal cord injury (SCI), we developed lentiviral vectors encoding calpain 1 shRNA and eGFP as a reporter (LV-CAPN1 shRNA). The ability of LV-CAPN1 shRNA to knockdown calpain 1 was confirmed in rat NRK cells using Northern and Western blot analysis. To investigate the effects on spinal cord injury, LV-CAPN1shRNA or LV-mismatch control shRNA (LV-control shRNA) were administered by convection enhanced diffusion at spinal cord level T10 in Long-Evans female rats (200-250 g) 1 week before contusion SCI, 180 kdyn force, or sham surgery at the same thoracic level. Intraspinal administration of the lentiviral particles resulted in transgene expression, visualized by eGFP, in spinal tissue at 2 weeks after infection. Calpain 1 protein levels were reduced by 54% at T10 2 weeks after shRNA-mediated knockdown (p<0.05, compared with the LV-control group, n=3 per group) while calpain 2 levels were unchanged. Intraspinal administration of LV-CAPN1shRNA 1 week before contusion SCI resulted in a significant improvement in locomotor function over 6 weeks postinjury, compared with LV-control administration (p<0.05, n=10 per group). Histological analysis of spinal cord sections indicated that pre-injury intraspinal administration of LV-CAPN1shRNA significantly reduced spinal lesion volume and improved total tissue sparing, white matter sparing, and gray matter sparing (p<0.05, n=10 per group). Together, results support the hypothesis that calpain 1 activation contributes to the tissue damage and impaired locomotor function after SCI, and that calpain1 represents a potential therapeutic target.


Assuntos
Calpaína/deficiência , Calpaína/genética , Traumatismos da Medula Espinal/genética , Traumatismos da Medula Espinal/metabolismo , Animais , Calpaína/fisiologia , Linhagem Celular , Feminino , Técnicas de Silenciamento de Genes/métodos , Atividade Motora/genética , RNA Interferente Pequeno/genética , Ratos , Ratos Long-Evans , Traumatismos da Medula Espinal/fisiopatologia , Sobrevivência de Tecidos/genética , Resultado do Tratamento
13.
J Neurophysiol ; 96(2): 569-78, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16641376

RESUMO

Cortical dysplasia (CD) is strongly associated with epilepsy. Enhanced excitability in dysplastic neuronal networks is believed to contribute to epileptogenesis, but the underlying mechanisms for the hyperexcitability are poorly understood. Cortical GABAergic interneurons provide the principal inhibition in the neuronal networks by forming inhibitory synapses on excitatory neurons. The aim of the present study was to determine if the function of interneurons in CD is compromised. In a rat model of CD, in utero irradiation, we studied spontaneous and miniature excitatory postsynaptic currents (sEPSCs and mEPSCs) in cortical interneurons using whole cell recording techniques. Two types of interneurons, type I and type II, were identified based on their distinctive spike patterns and short-term synaptic plasticity. We found that the frequencies of sEPSCs and mEPSCs were significantly decreased in both types of interneurons in CD. However, the amplitude and kinetics of sEPSCs and mEPSCs were not different. Five-pulse, 20-Hz stimulation produced short-term depression in type I interneurons in both CD and control tissue. Type II interneurons showed a robust short-term facilitation in both CD and control tissue. Morphological analysis of biocytin-filled neurons revealed that dendritic trees of both types of interneurons were not altered in CD. Our results demonstrate that the excitatory drive, namely sEPSCs and mEPSCs, in two main types of interneuron is largely attenuated in CD, probably due to a reduction in the number of excitatory synapses on both types of interneurons in CD.


Assuntos
Córtex Cerebral/fisiopatologia , Interneurônios/fisiologia , Animais , Lesões Encefálicas/fisiopatologia , Córtex Cerebral/citologia , Interpretação Estatística de Dados , Dendritos/fisiologia , Eletrofisiologia , Epilepsia/fisiopatologia , Potenciais Pós-Sinápticos Excitadores/fisiologia , Feminino , Técnicas In Vitro , Plasticidade Neuronal/fisiologia , Técnicas de Patch-Clamp , Gravidez , Células Piramidais/fisiologia , Ratos , Ratos Sprague-Dawley
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