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1.
Nat Immunol ; 19(12): 1319-1329, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30397348

RESUMO

Many tumors evolve sophisticated strategies to evade the immune system, and these represent major obstacles for efficient antitumor immune responses. Here we explored a molecular mechanism of metabolic communication deployed by highly glycolytic tumors for immunoevasion. In contrast to colon adenocarcinomas, melanomas showed comparatively high glycolytic activity, which resulted in high acidification of the tumor microenvironment. This tumor acidosis induced Gprotein-coupled receptor-dependent expression of the transcriptional repressor ICER in tumor-associated macrophages that led to their functional polarization toward a non-inflammatory phenotype and promoted tumor growth. Collectively, our findings identify a molecular mechanism of metabolic communication between non-lymphoid tissue and the immune system that was exploited by high-glycolytic-rate tumors for evasion of the immune system.


Assuntos
Adenocarcinoma/imunologia , Macrófagos/imunologia , Melanoma/imunologia , Evasão Tumoral/imunologia , Microambiente Tumoral/imunologia , Acidose/imunologia , Adenocarcinoma/metabolismo , Animais , Neoplasias do Colo/imunologia , Neoplasias do Colo/metabolismo , Glicólise/imunologia , Humanos , Melanoma/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos
2.
Int J Mol Sci ; 23(15)2022 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-35955653

RESUMO

We previously demonstrated the marked hepatosteatosis and endothelial dysfunction in hepatocyte-specific ERK2 knockout mice (LE2KO) with a high-fat/high-sucrose diet (HFHSD), but detailed metabolic changes and the characteristics in insulin-sensitive organs were not tested. This study aimed to characterize metabolic remodeling with changes in insulin-sensitive organs, which could induce endothelial dysfunction in HFHSD-LE2KO. The serum glucose and fatty acid (FA) were modestly higher in HFHSD-LE2KO than HFHSD-Control. FA synthesis genes were up-regulated, which was associated with the decreased phosphorylation of AMPK and ACC, and with the up-regulation of SREBP-1 in the liver from HFHSD-LE2KO. In FA and amino acids fraction analysis, arachidonic acid/eicosapentaenoic acid ratio, L-ornithine/arginine ratio, asymmetric dimethylarginine and homocysteine levels were elevated in HFHSD-LE2KO. Insulin-induced phosphorylation of AKT was blunted in skeletal muscle. Serum leptin and IL-1ß were elevated, and serum adiponectin was decreased with the enlargement of epididymal adipocytes. Finally, the enhanced superoxide levels in the aorta, which were blunted with CCCP, apocynin, and tempol, were observed in HFHSD-LE2KO. A pre-incubation of aortic rings with tempol improved endothelial dysfunction in HFHSD-LE2KO. HFHSD-LE2KO revealed an acceleration of FA synthesis in the liver leading to insulin resistance in skeletal muscle and the enlargement of visceral adipocytes. Global metabolic remodeling such as changes in arginine metabolism, ω3/ω6 ratio, and adipocytokines, could affect the vascular oxidative stress and endothelial dysfunction in HFHSD-LE2KO.


Assuntos
Dieta Hiperlipídica , Fígado , Animais , Arginina/metabolismo , Dieta Hiperlipídica/efeitos adversos , Ácidos Graxos/metabolismo , Insulina/metabolismo , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Estresse Oxidativo , Fosforilação , Sacarose/metabolismo
3.
J Neurosci Res ; 99(6): 1666-1688, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33729593

RESUMO

Nervous systems are designed to become extra sensitive to afferent nociceptive stimuli under certain circumstances such as inflammation and nerve injury. How pain hypersensitivity comes about is key issue in the field since it ultimately results in chronic pain. Central sensitization represents enhanced pain sensitivity due to increased neural signaling within the central nervous system (CNS). Particularly, much evidence indicates that underlying mechanism of central sensitization is associated with the change of spinal neurons. Extracellular signal-regulated kinases have received attention as key molecules in central sensitization. Previously, we revealed the isoform-specific function of extracellular signal-regulated kinase 2 (Erk2) in spinal neurons for central sensitization using mice with Cre-loxP-mediated deletion of Erk2 in the CNS. Still, how extracellular signal-regulated kinase 5 (Erk5) in spinal neurons contributes to central sensitization has not been directly tested, nor is the functional relevance of Erk5 and Erk2 known. Here, we show that Erk5 and Erk2 in the CNS play redundant and/or distinct roles in central sensitization, depending on the plasticity context (cell types, pain types, time, etc.). We used male mice with Erk5 deletion specifically in the CNS and found that Erk5 plays important roles in central sensitization in a formalin-induced inflammatory pain model. Deletion of both Erk2 and Erk5 leads to greater attenuation of central sensitization in this model, compared to deletion of either isoform alone. Conversely, Erk2 but not Erk5 plays important roles in central sensitization in neuropathic pain, a type of chronic pain caused by nerve damage. Our results suggest the elaborate mechanisms of Erk signaling in central sensitization.


Assuntos
Hiperalgesia/genética , Sistema de Sinalização das MAP Quinases/genética , Proteína Quinase 1 Ativada por Mitógeno/genética , Proteína Quinase 7 Ativada por Mitógeno/genética , Animais , Comportamento Animal , Dor Crônica/genética , Dor Crônica/fisiopatologia , Dor Crônica/psicologia , Hiperalgesia/fisiopatologia , Hiperalgesia/psicologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína Quinase 1 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 7 Ativada por Mitógeno/antagonistas & inibidores , Neuralgia/genética , Neuralgia/fisiopatologia , Neuralgia/psicologia , Neurônios/metabolismo , Dor/fisiopatologia , Medição da Dor , Medula Espinal/citologia , Medula Espinal/metabolismo
4.
Allergy ; 76(11): 3422-3432, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33884632

RESUMO

BACKGROUND: Itch is a common cutaneous symptom in a variety of dermatological diseases, but detailed neuropathological mechanisms remain to be fully elucidated. This study aimed to assess in vivo ERK2 functions in the nervous system for itch responses. METHODS: We generated conditional knockout mice deficient in ERK2 of the central nervous system (CNS) or peripheral nervous system (PNS), respectively, and assessed chemical and mechanical itch responses in vivo. RESULTS: Chemical itch responses to histamine, but not to BAM8-22, were alleviated in CNS Erk2-deficient mice. In contrast, both histamine- and BAM8-22-induced mechanical itch (alloknesis) were alleviated in CNS Erk2-deficient mice. Neither chemical itch nor mechanical itch induced by these pruritogens was affected by PNS ERK2 deficiency. Spontaneous scratching behaviors during acute and chronic contact hypersensitivity were impaired in CNS Erk2-deficient mice, but not PNS Erk2-deficient mice. In addition, CNS ERK2 deficiency attenuated mechanical itch responses during chronic contact hypersensitivity. Again, PNS Erk2-deficient mice showed comparable responses of mechanical itch to control mice. In addition, alleviated mechanical itch in CNS Erk2-deficient mice was observed in IgE-mediated prurigo-like allergic skin inflammation. Mechanical itch induced by IL-31 was also alleviated by CNS ERK2 deficiency. Phosphorylated ERK1/2 was detected in neurokinin B-expressing cells of the spinal dorsal horn of control mice; these cells accumulated during the induction of chronic contact hypersensitivity. Notably, phosphorylated ERK1/2 was also localized in spinal urocortin3-expressing neurons that are known to transmit mechanical itch. CONCLUSIONS: Spinal cord ERK2 could be a potential therapeutic target for intractable itch in pruritic skin diseases.


Assuntos
Sistema de Sinalização das MAP Quinases , Proteína Quinase 1 Ativada por Mitógeno , Prurido , Animais , Modelos Animais de Doenças , Inflamação , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína Quinase 1 Ativada por Mitógeno/genética , Sistema Nervoso Periférico , Pele
5.
FASEB J ; 34(8): 11272-11291, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32602979

RESUMO

ICER (inducible cAMP early repressor) isoforms are transcriptional repressors encoded by the Crem (cAMP responsive element modulator) gene. They were linked to the regulation of a multitude of cellular processes and pathophysiological mechanisms. Here, we show for the first time that two independent induction patterns for CREM repressor isoforms exist in the heart, namely for ICER and smICER (small ICER), which are induced in response to ß-adrenergic stimulation in a transient- and saturation-like manner, respectively. This time-shifted induction pattern, driven by two internal promoters in the Crem gene, leads to the predominant transcription of smIcer after prolonged ß-adrenergic stimulation. Using an ICER knockout mouse model with preserved smICER induction, we show that the transient-like induction of Icer itself has minor effects on gene regulation, cardiac hypertrophy or contractile function in the heart. We conclude that the functions previously linked to ICER may be rather attributed to smICER, also beyond the cardiac background.


Assuntos
Agonistas Adrenérgicos beta/farmacologia , Modulador de Elemento de Resposta do AMP Cíclico/genética , Receptores Adrenérgicos beta/genética , Animais , Cardiomegalia/tratamento farmacológico , Linhagem Celular , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/genética , Células HEK293 , Coração/efeitos dos fármacos , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Regiões Promotoras Genéticas/efeitos dos fármacos , Regiões Promotoras Genéticas/genética , Transcrição Gênica/efeitos dos fármacos , Transcrição Gênica/genética
6.
J Clin Biochem Nutr ; 69(3): 256-264, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34857987

RESUMO

Obesity induces severe disorders such as type 2 diabetes and cardiovascular events, and the number of people with obesity is increasing all over the world. Furthermore, it is possible that obesity increases the risk of cognitive dysfunction via the acceleration of oxidative damage. Tocotrienols, which are part of the vitamin E family, have antioxidant and anti-obesity effects. However, the effects of tocotrienols on high-fat diet-treated mice have not been completely elucidated. In this study, we assessed changes in body weight, spatial reference memory acquisition, liver lipid droplet size, blood brain barrier-related protein expressions and antioxidative defense systems in high-fat diet-treated mice in the presence or absence of tocotrienols. The results showed that tocotrienols significantly inhibited body weight gain and lipid droplet synthesis. Although the amount was very small, it was confirmed that tocotrienols surely reached the brain in the perfused brain. Treatment with tocotrienols was tended to improve cognitive function in the control mice. However, tocotrienols did not modulate blood brain barrier-related protein expressions or antioxidative defense systems. These results indicate that treatment with tocotrienols could be effective for the prevention of obesity and cognitive dysfunction. Further extended research is needed to elucidate the relationship between anti-obesity and antioxidant effects of tocotrienols, especially in the brain.

7.
Biochem Biophys Res Commun ; 511(1): 141-147, 2019 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-30773263

RESUMO

We previously reported that 8-nitroguanosine 3',5'-cyclic monophosphate (8-nitro-cGMP) is endogenously produced via nitric oxide/reactive oxygen species signaling pathways and it reacts with protein thiol residues to add cGMP structure to proteins through S-guanylation. S-Guanylation occurs on synaptosomal-associated protein 25 (SNAP-25), which is a part of the soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE) complex that regulates exocytosis. However, the biological relevance of 8-nitro-cGMP in the nervous system remains unclear. Here, we investigated the effects of intracerebroventricular (icv) infusion of 8-nitro-cGMP on mouse brain functions. The results of an open-field test and fear-conditioning task revealed that icv infusion of 8-nitro-cGMP decreased the vertical activity and context-dependent fear memory of mice, which are both associated with the hippocampus. Immunohistochemical analysis revealed increased c-Fos-positive cells in the dentate gyrus in 8-nitro-cGMP-infused mice. Further, biochemical analyses showed that icv infusion of 8-nitro-cGMP increased S-guanylated proteins including SNAP-25 and SNARE complex formation as well as decreased complexes containing complexin, which regulates exocytosis by binding to the SNARE complex, in the hippocampus. These findings suggest that accumulation of 8-nitro-cGMP in the hippocampus affects its functions, including memory, via S-guanylation of hippocampal proteins such as SNAP-25.


Assuntos
GMP Cíclico/análogos & derivados , Medo , Memória , Animais , Encéfalo/fisiologia , Condicionamento Clássico , GMP Cíclico/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Óxido Nítrico/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Proteína 25 Associada a Sinaptossoma/metabolismo
8.
Arch Biochem Biophys ; 663: 120-128, 2019 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-30629958

RESUMO

BACKGROUND: Vitamin C (l-ascorbic acid, VC) and vitamin E (α-tocopherol, VE) play important physiological roles as endogenous antioxidants in many tissues and organs. However, their roles in the brain remain entirely elusive. We established senescence marker protein 30 (SMP30)/α-tocopherol transfer protein (αTTP) double knockout (DKO) mice as a novel VC and VE double-deficiency model and examined the effect of VC and VE double-deficiency on brain functions. METHODS: DKO and wild-type (WT) mice were divided into the following two groups: mice in the CE (+) group were supplied with sufficient amounts of VC and VE and mice in the CE (-) group were deficient in both VC and VE. After 8 weeks of CE (+) or CE (-) treatments, a battery of behavioral experiments was conducted to analyze cognitive functions, including memory, through the Morris water maze and Pavlovian fear conditioning tasks. RESULTS: The plasma VC and VE levels in DKO-CE (-) mice and VE level in WT-CE (-) mice were almost completely depleted after 8 weeks of the deficient treatment. The behavioral study revealed that the general behaviors, including locomotor activity and anxiety level, were not influenced by the CE (-) treatment in DKO and WT mice. However, in the Pavlovian fear conditioning task, DKO-CE (-) mice showed impaired conditioned fear memory compared with that of DKO-CE (+) mice. Furthermore, increased mRNA expression was observed in inflammatory-related genes, such as IL-6, TNFα, F4/80, and Mcp-1, in the hippocampus of DKO-CE (-) mice. CONCLUSIONS: The findings of this study provide evidence that VC and VE deficiency led to impaired conditioned fear memory possibly caused by neuroinflammation in the brain.


Assuntos
Deficiência de Ácido Ascórbico/complicações , Encéfalo/patologia , Condicionamento Clássico , Medo , Inflamação/complicações , Memória , Deficiência de Vitamina E/complicações , Animais , Ácido Ascórbico/sangue , Encéfalo/fisiopatologia , Proteínas de Ligação ao Cálcio/genética , Proteínas de Transporte/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Aprendizagem em Labirinto , Camundongos , Camundongos Knockout , Vitamina E/sangue
9.
No Shinkei Geka ; 44(7): 555-60, 2016 Jul.
Artigo em Japonês | MEDLINE | ID: mdl-27384115

RESUMO

Embosphere® was approved in Japan for embolizing intracranial arteries for the reduction of intraoperative bleeding in January 2014. Until August 2015, we performed embolization for four meningiomas using Embosphere®. We performed an initial evaluation of all the cases, including evaluation of the clinical courses, change in the maximum tumor diameters and volumes, alteration in the appearance on magnetic resonance imaging(MRI), amount of intraoperative bleeding, complications, and histopathological findings. After embolization, the maximum tumor diameters and volumes slightly decreased on MRI, whereas the signal change on diffusion-weighted imaging(DWI)or fluid-attenuated inversion recovery(FLAIR)varied in each case. One case demonstrated a partial signal change on DWI one day after the initial procedure, and another case demonstrated a decrease in perifocal edema on FLAIR. Among our patients, least bleeding was recorded at 6 days after the embolization. Histopathological analysis revealed coagulative necrotic lesions in two cases. The von Kossa stain was used to distinguish Embosphere® from the psammoma body. One case involved a thromboembolic complication of the retinocentral artery caused by an Embosphere® of 100-300 µm. Our early-stage experience suggests that an Embosphere® of 300-500 µm should be used for safe embolization before resection to avoid thromboembolic complications because an Embosphere® of 100-300 µm can pass through the dangerous anastomosis. Our present strategy was to resect the tumor approximately seven days after the embolization using Embosphere®. However, further studies and discussion on the size of Embosphere®, and the interval between pre-operative embolization and surgical removal are needed.


Assuntos
Embolização Terapêutica , Neoplasias Meníngeas/terapia , Meningioma/terapia , Idoso , Angiografia Cerebral , Imagem de Difusão por Ressonância Magnética , Embolização Terapêutica/instrumentação , Feminino , Humanos , Masculino , Neoplasias Meníngeas/diagnóstico por imagem , Meningioma/diagnóstico por imagem
10.
Neurol Neurochir Pol ; 50(6): 504-510, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27575680

RESUMO

BACKGROUND: Compared with surgical resection, endoscopic transsphenoidal surgery (TSS) for cholesterol granuloma (CG) in the petrous apex (PA) is associated with local recurrence due to obstruction of the drainage route. We present a detailed procedure of an endoscopic TSS using pedicle vascularized nasoseptal flap (PVNF). METHODS: A 40-year-old woman with a history of repeated surgery for left tympanitis was referred to our institution. Neurological examination revealed severe hearing loss in the left ear. Radiologic examination presented a round mass in the left PA and significant fluid collection in the mastoid air cells of the left temporal bone. CG was strongly suspected, and endoscopic TSS using PVNF was performed. Prior to endoscopic drainage, a PVNF was harvested from the mucosa of the ipsilateral nasal septum, with an attempt to preserve the sphenopalatine artery in the flap. Following this, puncture and adequate irrigation of the lesion was performed by endoscopic TSS, with neuro-navigation system assistance; the apex of PVNF was then placed into the lesion to prevent the obstruction of the drainage route. An absorbable polyglycolic acid sheet and fibrin glue were applied on the flap to prevent spontaneous deviation from the lesion. RESULTS: The patient was discharged without any further neurological complications. Eight-month postoperative computed tomography images showed no recurrence; the drainage route was patent and the fluid collection in the left mastoid air cells was resolved. Moreover, hearing loss was improved. CONCLUSIONS: Endoscopic TSS using PVNF may be one of available surgical options for PACG.


Assuntos
Colesterol , Endoscopia/métodos , Granuloma de Corpo Estranho/cirurgia , Septo Nasal/transplante , Osso Petroso/cirurgia , Retalhos Cirúrgicos , Adulto , Feminino , Granuloma de Corpo Estranho/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Osso Petroso/diagnóstico por imagem , Tomografia Computadorizada por Raios X
11.
No Shinkei Geka ; 43(7): 603-10, 2015 Jul.
Artigo em Japonês | MEDLINE | ID: mdl-26136324

RESUMO

BACKGROUND: In Japan, patients with malignant glioma have been treated with BCNU wafers (Gliadel®) since January 2013. Several adverse events(AEs)associated with implantation of BCNU wafers, including cerebral edema or cyst formation, are recognized. Here, we report a retrospective review of the experience with implantation of BCNU wafers in our institutions and our findings regarding the risk factors for the AEs. METHODS: We reviewed the records of patients with malignant glioma who were implanted with BCNU wafers between April 2013 and September 2014. Their AEs were examined clinically and radiologically and evaluated according to Common Terminology Criteria for Adverse Events (CTCAE) grading. For investigating the association between risk factors and incidence of AEs, histological diagnosis, extent of resection, and period of BCNU wafers implantation surgery were selected as possible risk factors. RESULTS: Twenty-one patients were included in this investigation. There were no associations among incidence of AEs and histological diagnosis or extent of tumor resection. However, regarding the period of BCNU wafers implantation, additional resection for newly diagnosed tumors and resection for recurrent tumors tended to increase the rate and severity of AEs, especially cerebral edema, compared to primary resection. CONCLUSION: In cases of BCNU wafers implantation, the incidence and degree of AEs might increase if additional resection for newly diagnosed tumors or resection for recurrent tumors is performed. Our investigation revealed that AEs associated with implantation of BCNU wafers tend to occur in the repeated glioma surgery.


Assuntos
Antineoplásicos Alquilantes/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Carmustina/uso terapêutico , Ácidos Decanoicos/uso terapêutico , Glioma/tratamento farmacológico , Poliésteres/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos Alquilantes/administração & dosagem , Antineoplásicos Alquilantes/efeitos adversos , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/cirurgia , Carmustina/administração & dosagem , Carmustina/efeitos adversos , Terapia Combinada , Ácidos Decanoicos/administração & dosagem , Ácidos Decanoicos/efeitos adversos , Progressão da Doença , Feminino , Glioma/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Poliésteres/administração & dosagem , Poliésteres/efeitos adversos , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento
12.
J Mol Cell Cardiol ; 72: 104-16, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24631771

RESUMO

Mitogen-activated protein kinases (MAPKs) are involved in the regulation of cardiac hypertrophy and myocyte survival. Extracellular signal regulated protein kinase 1 and 2 (ERK1/2) are key components in the MAPK signaling pathways. Dysfunction of ERK1/2 in congenital heart diseases (Noonan syndrome and LEOPARD syndrome) leads to cardiac hypertrophy. ERK2 contributes 70% of protein content to total ERK1/2 content in myocardium; however, the specific role of ERK2 in regulating cardiac hypertrophy is yet to be further defined. To investigate the specific role of ERK2 played in the cardiomyocytes, we generated and examined mice with cardiomyocyte-specific deletion of the erk2 gene (ERK2(cko) mice). Following short-term pathological hypertrophic stresses, the mutant mice showed attenuated hypertrophic remodeling characterized by a blunted increase in the cross-sectional area of individual myocytes, downregulation of hypertrophic foetal gene markers (ANP and BNP), and less interstitial fibrosis. However, increased cardiomyocyte apoptosis was observed. Upon prolonged stimulation, ERK2(cko) mice developed deterioration in cardiac function. However, absence of ERK2 did not affect physiological hypertrophy induced by 4weeks of swimming exercise. These results revealed an essential role for ERK2 in cardiomyocytes in the development of pathological hypertrophic remodeling and resistance to cell death.


Assuntos
Cardiomegalia/fisiopatologia , Proteína Quinase 1 Ativada por Mitógeno/deficiência , Miocárdio/patologia , Miócitos Cardíacos/metabolismo , Animais , Apoptose , Fator Natriurético Atrial/genética , Fator Natriurético Atrial/metabolismo , Cardiomegalia/metabolismo , Cardiomegalia/patologia , Fibrose , Regulação da Expressão Gênica , Masculino , Camundongos , Camundongos Knockout , Proteína Quinase 1 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Miocárdio/metabolismo , Miócitos Cardíacos/patologia , Peptídeo Natriurético Encefálico/genética , Peptídeo Natriurético Encefálico/metabolismo , Cultura Primária de Células , Estresse Fisiológico , Natação
13.
J Neurochem ; 131(5): 675-87, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25066807

RESUMO

Temporal lobe epilepsy (TLE) often becomes refractory, and patients with TLE show a high incidence of psychiatric symptoms, including anxiety and depression. Therefore, it is necessary to identify molecules that were previously unknown to contribute to epilepsy and its associated disorders. We previously found that the sialyltransferase ST3Gal IV is up-regulated within the neural circuits through which amygdala-kindling stimulation propagates epileptic seizures. In contrast, this study demonstrated that kindling stimulation failed to evoke epileptic seizures in ST3Gal IV-deficient mice. Furthermore, approximately 80% of these mice failed to show tonic-clonic seizures with stimulation, whereas all littermate wild-type mice showed tonic-clonic seizures. This indicates that the loss of ST3Gal IV does not cause TLE in mice. Meanwhile, ST3Gal IV-deficient mice exhibited decreased acclimation in the open field test, increased immobility in the forced swim test, enhanced freezing during delay auditory fear conditioning, and sleep disturbances. Thus, the loss of ST3Gal IV modulates anxiety-related behaviors. These findings indicate that ST3Gal IV is a key molecule in the mechanisms underlying anxiety - a side effect of TLE - and may therefore also be an effective target for treating epilepsy, acting through the same circuits.


Assuntos
Epilepsia do Lobo Temporal/prevenção & controle , Deleção de Sequência/genética , Sialiltransferases/deficiência , Animais , Condicionamento Psicológico/fisiologia , Modelos Animais de Doenças , Estimulação Elétrica/efeitos adversos , Eletroencefalografia , Epilepsia do Lobo Temporal/etiologia , Epilepsia do Lobo Temporal/genética , Epilepsia do Lobo Temporal/fisiopatologia , Comportamento Exploratório/fisiologia , Medo/psicologia , Elevação dos Membros Posteriores , Hipocampo/fisiopatologia , Excitação Neurológica/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Sialiltransferases/genética , Sono/genética , Natação/psicologia , beta-Galactosídeo alfa-2,3-Sialiltransferase
14.
Nucleic Acids Res ; 40(5): 1944-53, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22075994

RESUMO

The RNA binding protein HuD plays essential roles in neuronal development and plasticity. We have previously shown that HuD stimulates translation. Key for this enhancer function is the linker region and the poly(A) binding domain of HuD that are also critical for its function in neurite outgrowth. Here, we further explored the underlying molecular interactions and found that HuD but not the ubiquitously expressed HuR interacts directly with active Akt1. We identify that the linker region of HuD is required for this interaction. We also show by using chimeric mutants of HuD and HuR, which contain the reciprocal linker between RNA-binding domain 2 (RBD2) and RBD3, respectively, and by overexpressing a dominant negative mutant of Akt1 that the HuD-Akt1 interaction is functionally important, as it is required for the induction of neurite outgrowth in PC12 cells. These results suggest the model whereby RNA-bound HuD functions as an adapter to recruit Akt1 to trigger neurite outgrowth. These data might also help to explain how HuD enhances translation of mRNAs that encode proteins involved in neuronal development.


Assuntos
Proteínas ELAV/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Proteínas ELAV/química , Células HeLa , Humanos , Neuritos/enzimologia , Células PC12 , Domínios e Motivos de Interação entre Proteínas , Ratos
15.
Hum Cell ; 37(5): 1553-1558, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39052150

RESUMO

In the past few decades, the global prevalence of diabetes has provided us with a warning about future chronic complications. Diabetic nephropathy (DN) is the main cause of end-stage kidney disease. Podocytes in the glomerulus play a critical role in regulating glomerular permeability, and podocyte injury is one of the main causes of DN. Extracellular signal-regulated kinase (ERK) is a member of the mitogen-activated protein kinase family that plays critical roles in intracellular signal transduction. In human patients with DN, phosphorylated ERK (pERK), the active form of ERK, is increased in the glomeruli. However, information on the expression of pERK, specifically in podocytes in DN, is limited. Meanwhile, high glucose induces ERK activation in immortalized podocyte cell lines, suggesting the involvement of podocytic ERK in DN. We performed an immunohistochemical study using Wilms' tumor-1 (WT-1) as a podocyte-specific marker to investigate whether podocytic pERK levels are increased in patients with DN. In the glomeruli of the DN group, we observed remarkable co-staining for WT-1 and pERK. In contrast, the glomeruli of the control group contained only a few pERK-positive podocytes. Statistical analyses revealed that, relative to healthy controls, patients with DN showed significantly increased pERK expression levels in cells that were positive for WT-1 (DN: 51.3 ± 13.1% vs. control: 7.3 ± 1.6%, p = 0.0158, t-test, n = 4 for each group). This suggests that ERK activation in podocytes is involved in the pathogenesis of DN.


Assuntos
Nefropatias Diabéticas , MAP Quinases Reguladas por Sinal Extracelular , Podócitos , Humanos , Podócitos/metabolismo , Podócitos/patologia , Nefropatias Diabéticas/metabolismo , Nefropatias Diabéticas/patologia , Nefropatias Diabéticas/etiologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Masculino , Feminino , Pessoa de Meia-Idade , Proteínas WT1/metabolismo , Proteínas WT1/genética , Fosforilação , Ativação Enzimática , Idoso , Adulto , Glomérulos Renais/patologia , Glomérulos Renais/metabolismo
16.
Exp Gerontol ; 196: 112555, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39179160

RESUMO

Age-related physical and cognitive decline may be ameliorated by consuming functional foods. d-Allose, reported to have multiple health benefits, may temper aging phenotypes, particularly brain function. We investigated whether d-allose supplementation improves cognitive function. A standard battery of behavioral tests was administered to 18-month-old male mice after consuming diet containing 3 % d-allose for 6 months. Following a wire-hanging test, an open-field test, Morris water maze, fear-conditioning, and an analgesia test were sequentially performed. Bone density and strength were assessed afterwards. Possible mechanism(s) under-lying memory changes in hippocampus were also examined with a DNA microarray. d-Allose failed to influence muscle strength, locomotor activity and anxiety, fear memory, or pain sensitivity. However, d-allose improved hippocampus-dependent spatial learning and memory, and it may contribute to increase bone strength. d-Allose also changed the expression of some genes in hippocampus involved in cognitive functions. Long-term d-allose supplementation appears to modestly change aging phenotypes and improve spatial memory.


Assuntos
Envelhecimento , Densidade Óssea , Disfunção Cognitiva , Hipocampo , Animais , Masculino , Camundongos , Hipocampo/efeitos dos fármacos , Envelhecimento/fisiologia , Disfunção Cognitiva/tratamento farmacológico , Densidade Óssea/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Força Muscular/efeitos dos fármacos , Aprendizagem em Labirinto/efeitos dos fármacos , Comportamento Animal/efeitos dos fármacos , Suplementos Nutricionais
17.
Redox Biol ; 70: 103053, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38340634

RESUMO

Although reactive oxygen species (ROS) are known to have harmful effects in organisms, recent studies have demonstrated expression of ROS synthases at various parts of the organisms and the controlled ROS generation, suggesting possible involvement of ROS signaling in physiological events of individuals. However, physiological roles of ROS in the CNS, including functional roles in higher brain functions or neuronal activity-dependent ROS production, remain to be elucidated. Here, we demonstrated involvement of ROS - 8-NO2-cGMP signaling in motor learning and synaptic plasticity in the cerebellum. In the presence of inhibitors of ROS signal or ROS synthases, cerebellar motor learning was impaired, and the stimulus inducing long-term depression (LTD), cellular basis for the motor learning, failed to induce LTD but induced long-term potentiation (LTP)-like change at cerebellar synapses. Furthermore, ROS was produced by LTD-inducing stimulus in enzyme-dependent manner, and excess administration of the antioxidant vitamin E impaired cerebellar motor learning, suggesting beneficial roles of endogenous ROS in the learning. As a downstream signal, involvement of 8-NO2-cGMP in motor learning and cerebellar LTD were also revealed. These findings indicate that ROS - 8-NO2-cGMP signal is activated by neuronal activity and is essential for cerebellum-dependent motor learning and synaptic plasticity, demonstrating involvement of the signal in physiological function of brain systems.


Assuntos
GMP Cíclico/análogos & derivados , Plasticidade Neuronal , Dióxido de Nitrogênio , Humanos , Espécies Reativas de Oxigênio/metabolismo , Dióxido de Nitrogênio/metabolismo , Plasticidade Neuronal/fisiologia , Cerebelo/metabolismo , Memória de Longo Prazo
18.
BMC Genomics ; 14: 248, 2013 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-23586671

RESUMO

BACKGROUND: Senescence-accelerated mice (SAM) are a series of mouse strains originally derived from unexpected crosses between AKR/J and unknown mice, from which phenotypically distinct senescence-prone (SAMP) and -resistant (SAMR) inbred strains were subsequently established. Although SAMP strains have been widely used for aging research focusing on their short life spans and various age-related phenotypes, such as immune dysfunction, osteoporosis, and brain atrophy, the responsible gene mutations have not yet been fully elucidated. RESULTS: To identify mutations specific to SAMP strains, we performed whole exome sequencing of 6 SAMP and 3 SAMR strains. This analysis revealed 32,019 to 38,925 single-nucleotide variants in the coding region of each SAM strain. We detected Ogg1 p.R304W and Mbd4 p.D129N deleterious mutations in all 6 of the SAMP strains but not in the SAMR or AKR/J strains. Moreover, we extracted 31 SAMP-specific novel deleterious mutations. In all SAMP strains except SAMP8, we detected a p.R473W missense mutation in the Ldb3 gene, which has been associated with myofibrillar myopathy. In 3 SAMP strains (SAMP3, SAMP10, and SAMP11), we identified a p.R167C missense mutation in the Prx gene, in which mutations causing hereditary motor and sensory neuropathy (Dejerine-Sottas syndrome) have been identified. In SAMP6 we detected a p.S540fs frame-shift mutation in the Il4ra gene, a mutation potentially causative of ulcerative colitis and osteoporosis. CONCLUSIONS: Our data indicate that different combinations of mutations in disease-causing genes may be responsible for the various phenotypes of SAMP strains.


Assuntos
Envelhecimento/genética , Doença/genética , Exoma/genética , Genômica , Mutação/genética , Análise de Sequência , Sequência de Aminoácidos , Animais , Sequência de Bases , Éxons/genética , Humanos , Proteínas de Membrana/química , Proteínas de Membrana/genética , Camundongos , Dados de Sequência Molecular , Fenótipo , Especificidade da Espécie
19.
Neuropathology ; 33(2): 185-91, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22765644

RESUMO

In the CNS, primary tumors with rhabdoid components are classified as atypical teratoid/rhabdoid tumor, rhabdoid meningioma or rhabdoid glioblastoma. The authors present a young adult patient with supratentorial rhabdoid tumor incidentally found after head trauma as a small pre-existing lesion in the parahippocampal gyrus. MRI demonstrated an area of hypointensity on T1-weighted images and hyperintensity on T2-weighted and fluid attenuated inversion recovery images. A serial MR scan revealed no change 3 months after the initial examination but drastic changes at 6 months. As the tumor and accompanying intratumoral hemorrhage enlarged rapidly, resection of the tumor was performed. Histopathology revealed that the main component of the tumor was typical rhabdoid cells with some necrotic areas. There were also pathological features consistent with oligoastrocytoma. The specimen had neither vascular proliferation usually seen in high-grade glioma nor the meningothelial pattern that suggests meningioma. Immunohistochemical findings revealed that cells were strongly positive for vimentin, epithelial membrane antigen and INI-1 antibody throughout the specimen. Further, monosomy 22 was detected by fluorescence in situ hybridization. The tumor was finally thought to be an unclassifiable primitive rhabdoid tumor with oligoastrocytoma that arose in the CNS. The patient died within 5 months of detection of the tumor, regardless of surgical resection, radiotherapy and chemotherapy.


Assuntos
Glioma/diagnóstico , Tumor Rabdoide/diagnóstico , Neoplasias Supratentoriais/diagnóstico , Evolução Fatal , Glioma/terapia , Humanos , Masculino , Tumor Rabdoide/terapia , Neoplasias Supratentoriais/terapia , Adulto Jovem
20.
J Neurosci ; 31(24): 8958-66, 2011 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-21677179

RESUMO

We developed a new protocol that induces long-term adaptation of horizontal optokinetic response (HOKR) eye movement by hours of spaced training and examined the role of protein synthesis in the cerebellar cortex in the formation of memory of adaptation. Mice were trained to view 800 cycles of screen oscillation either by 1 h of massed training or by 2.5 h to 8 d of training with 0.5 h to 1 d space intervals. The HOKR gains increased similarly by 20-30% at the end of training; however, the gains increased by 1 h of massed training recovered within 24 h, whereas the gains increased by spaced training were sustained over 24 h. Bilateral floccular lidocaine microinfusions immediately after the end of training recovered the gains increased by 1 h of massed training but did not affect the gains increased by 4 h of spaced training, suggesting that the memory trace of adaptation was transferred from the flocculus to the vestibular nuclei within 4 h of spaced training. Blockade of floccular protein synthesis, examined by bilateral floccular microinfusions of anisomycin or actinomycin D 1-4 h before the training, impaired the gains increased by 4 h of spaced training but did not affect the gains increased by 1 h of massed training. These findings suggest that the transfer of the memory trace of adaptation occurs within 4 h of spaced training, and proteins synthesized in the flocculus during training period may play an important role in memory transfer.


Assuntos
Adaptação Ocular/fisiologia , Anisomicina/farmacologia , Córtex Cerebelar/efeitos dos fármacos , Cerebelo/fisiologia , Aprendizagem/fisiologia , Movimento/fisiologia , Inibidores da Síntese de Proteínas/farmacologia , Transferência de Experiência/fisiologia , Adaptação Ocular/efeitos dos fármacos , Anestésicos Locais , Animais , Córtex Cerebelar/lesões , Córtex Cerebelar/metabolismo , Movimentos Oculares/fisiologia , Lateralidade Funcional , Lidocaína/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microinjeções/métodos , Movimento/efeitos da radiação , Estimulação Luminosa , Células de Purkinje/efeitos dos fármacos , Células de Purkinje/fisiologia , Fatores de Tempo , Transferência de Experiência/efeitos dos fármacos
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