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1.
Cancers (Basel) ; 16(5)2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38473298

RESUMO

The Epstein-Barr virus (EBV) is accepted as a primary risk factor for certain nasopharyngeal carcinoma (NPC) subtypes, where the virus persists in a latent stage which is thought to contribute to tumorigenesis. Current treatments are sub-optimal, and recurrence occurs in many cases. An alternative therapeutic concept is aimed at triggering the lytic cycle of EBV selectively in tumor cells as a means to add clinical benefit. While compounds able to stimulate the lytic cascade have been identified, their clinical application so far has been limited. We are developing a novel anticancer molecule, NEO212, that was generated by covalent conjugation of the alkylating agent temozolomide (TMZ) to the naturally occurring monoterpene perillyl alcohol (POH). In the current study, we investigated its potential to trigger the lytic cycle of EBV in NPC cells in vitro and in vivo. We used the established C666.1 cell line and primary patient cells derived from the brain metastasis of a patient with NPC, both of which harbored latent EBV. Upon treatment with NEO212, there was an increase in EBV proteins Zta and Ea-D, key markers of the lytic cycle, along with increased levels of CCAAT/enhancer-binding protein homologous protein (CHOP), a marker of endoplasmic reticulum (ER) stress, followed by the activation of caspases. These effects could also be confirmed in tumor tissue from mice implanted with C666.1 cells. Towards a mechanistic understanding of these events, we used siRNA-mediated knockdown of CHOP and inclusion of anti-oxidant compounds. Both approaches blocked lytic cycle induction by NEO212. Therefore, we established a sequence of events, where NEO212 caused reactive oxygen species (ROS) production, which triggered ER stress and elevated the levels of CHOP, which was required to stimulate the lytic cascade of EBV. Inclusion of the antiviral agent ganciclovir synergistically enhanced the cytotoxic impact of NEO212, pointing to a potential combination treatment for EBV-positive cancers which should be explored further. Overall, our study establishes NEO212 as a novel agent able to stimulate EBV's lytic cycle in NPC tumors, with implications for other virus-associated cancers.

2.
Cells ; 11(14)2022 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-35883580

RESUMO

Tumor suppressor WWOX inhibits cancer growth and retards Alzheimer's disease (AD) progression. Supporting evidence shows that the more strongly WWOX binds intracellular protein partners, the weaker is cancer cell growth in vivo. Whether this correlates with retardation of AD progression is unknown. Two functional forms of WWOX exhibit opposite functions. pY33-WWOX is proapoptotic and anticancer, and is essential for maintaining normal physiology. In contrast, pS14-WWOX is accumulated in the lesions of cancers and AD brains, and suppression of WWOX phosphorylation at S14 by a short peptide Zfra abolishes cancer growth and retardation of AD progression. In parallel, synthetic Zfra4-10 or WWOX7-21 peptide strengthens the binding of endogenous WWOX with intracellular protein partners leading to cancer suppression. Indeed, Zfra4-10 is potent in restoring memory loss in triple transgenic mice for AD (3xTg) by blocking the aggregation of amyloid beta 42 (Aß42), enhancing degradation of aggregated proteins, and inhibiting activation of inflammatory NF-κB. In light of the findings, Zfra4-10-mediated suppression of cancer and AD is due, in part, to an enhanced binding of endogenous WWOX and its binding partners. In this perspective review article, we detail the molecular action of WWOX in the HYAL-2/WWOX/SMAD4 signaling for biological effects, and discuss WWOX phosphorylation forms in interacting with binding partners, leading to suppression of cancer growth and retardation of AD progression.


Assuntos
Doença de Alzheimer , Neoplasias , Oxidorredutase com Domínios WW , Proteínas Adaptadoras de Transdução de Sinal/farmacologia , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Animais , Sobrevivência Celular , Progressão da Doença , Humanos , Imunidade/genética , Imunidade/fisiologia , Camundongos , Neoplasias/metabolismo , Fragmentos de Peptídeos/farmacologia , Isoformas de Proteínas/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Oxidorredutase com Domínios WW/metabolismo
3.
J Clin Invest ; 118(1): 133-48, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18079966

RESUMO

Secretoneurin (SN), a neuropeptide derived from secretogranin II, promotes neurite outgrowth of immature cerebellar granule cells. SN also aids in the growth and repair of neuronal tissue, although the precise mechanisms underlying the promotion of brain tissue neuroprotection and plasticity by SN are not understood. Here, in a rat model of stroke and in ischemic human brain tissue, SN was markedly upregulated in both neurons and endothelial cells. SN-mediated neuroprotection rescued primary cortical cell cultures from oxygen/glucose deprivation. SN also induced expression of the antiapoptotic proteins Bcl-2 and Bcl-xL through the Jak2/Stat3 pathway and inhibited apoptosis by blocking caspase-3 activation. In addition, rats with occluded right middle cerebral arteries showed less cerebral infarction, improved motor performance, and increased brain metabolic activity following i.v. administration of SN. Furthermore, SN injection enhanced stem cell targeting to the injured brain in mice and promoted the formation of new blood vessels to increase local cortical blood flow in the ischemic hemisphere. Both in vitro and in vivo, SN not only promoted neuroprotection, but also enhanced neurogenesis and angiogenesis. Our results demonstrate that SN acts directly on neurons after hypoxia and ischemic insult to further their survival by activating the Jak2/Stat3 pathway.


Assuntos
Infarto Cerebral/metabolismo , Janus Quinase 2/metabolismo , Plasticidade Neuronal/efeitos dos fármacos , Neuropeptídeos/farmacologia , Fármacos Neuroprotetores/farmacologia , Fator de Transcrição STAT3/metabolismo , Secretogranina II/farmacologia , Animais , Apoptose/efeitos dos fármacos , Caspase 3/metabolismo , Hipóxia Celular/efeitos dos fármacos , Células Cultivadas , Córtex Cerebelar/metabolismo , Córtex Cerebelar/patologia , Infarto Cerebral/tratamento farmacológico , Infarto Cerebral/patologia , Modelos Animais de Doenças , Ativação Enzimática/efeitos dos fármacos , Feminino , Humanos , Masculino , Camundongos , Neuritos/metabolismo , Neuritos/patologia , Neuropeptídeos/metabolismo , Fármacos Neuroprotetores/metabolismo , Ratos , Ratos Sprague-Dawley , Secretogranina II/metabolismo , Células-Tronco/metabolismo , Células-Tronco/patologia , Proteína bcl-X/metabolismo
4.
Mol Genet Metab ; 103(4): 367-77, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21620749

RESUMO

Globoid cell leukodystrophy (GLD) is a devastating lysosomal storage disease caused by deficiency of the enzyme galactocerebrosidase (GALC). Currently, there is no definite cure for GLD. Several attempts with CNS-directed gene therapy in twitcher mice (a murine model of GLD) demonstrated restricted expression of GALC activity in CNS and failure of therapeutic efficacy in cerebellum and spinal cord, resulting in various degrees of correction of biochemical, pathological and clinical phenotype. More recently, twitcher mice receiving a combination of hematopoietic and viral vector gene transfer therapies were not protected from neurodegeneration and axonopathy in both cerebellum and spinal cord. This evidence indicates the requirement of sufficient and widespread GALC expression in CNS and rescue of cerebellum and spinal cord in the therapeutic intervention of murine model of GLD. In this study, we have optimized intracranial delivery of AAV2/5-GALC to the neocortex, hippocampus and cerebellum, instead of the thalamus as was previously conducted, of twitcher mice. The CNS-targeted AAV2/5 gene transfer effectively dispersed GALC transgene along the neuraxis of CNS as far as the lumbar spinal cord, and reduced the accumulation of psychosine in the CNS of twitcher mice. Most importantly, the treated twitcher mice were protected from loss of oligodendrocytes and Purkinje cells, axonopathy and marked gliosis, and had significantly improved neuromotor function and prolonged lifespan. These preclinical findings with our approach are encouraging, although a more robust response in the spinal cord would be desirable. Collectively, the information in this study validates the efficacy of this gene delivery approach to correct enzymatic deficiency, psychosine accumulation and neuropathy in CNS of GLD. Combining cell therapy such as bone marrow transplantation with treatment with the aim of reducing inflammation, replacing dead or dying oligodendrocytes and targeting PNS may provide a synergistic and more complete correction of this disease.


Assuntos
Sistema Nervoso Central/patologia , Galactosilceramidase/genética , Leucodistrofia de Células Globoides/patologia , Leucodistrofia de Células Globoides/terapia , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Calbindinas , Células Cultivadas , Sistema Nervoso Central/metabolismo , Dependovirus/genética , Modelos Animais de Doenças , Galactosilceramidase/metabolismo , Técnicas de Transferência de Genes , Terapia Genética , Vetores Genéticos , Imuno-Histoquímica , Leucodistrofia de Células Globoides/genética , Camundongos , Camundongos Transgênicos , Proteína G de Ligação ao Cálcio S100/genética , Proteína G de Ligação ao Cálcio S100/metabolismo , Medula Espinal/metabolismo , Medula Espinal/patologia
5.
Am J Med Genet A ; 155A(12): 3095-9, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22052856

RESUMO

De Barsy syndrome (DBS) is characterized by progeroid features, ophthalmological abnormalities, intrauterine growth retardation, and cutis laxa. Recently, PYCR1 mutations were identified in cutis laxa with progeroid features. Herein, we report on a DBS patient born to a nonconsanguineous Chinese family. The exceptional observation of congenital glaucoma, aortic root dilatation, and idiopathic hypertrophic pyloric stenosis in this patient widened the range of symptoms that have been noted in DBS. Mutation analysis of PYCR1 revealed compound heterozygous PYCR1 mutations, including a p.P115fsX7 null mutation allele and a second allele with two missense mutations in cis: p.G248E and p.G297R. The effect of mutation results in a reduction of PYCR1 mRNA expression and PYCR1 protein expression in skin fibroblasts from the patient. The findings presented here suggest a mutation screening of PYCR1 and cardiovascular survey in patients with DBS.


Assuntos
Opacidade da Córnea/genética , Cútis Laxa/genética , Heterozigoto , Deficiência Intelectual/genética , Mutação , Fenótipo , Pirrolina Carboxilato Redutases/genética , Anormalidades Múltiplas/genética , Sequência de Bases , Criança , Pré-Escolar , Opacidade da Córnea/diagnóstico , Cútis Laxa/diagnóstico , Éxons , Expressão Gênica , Humanos , Deficiência Intelectual/diagnóstico , Masculino , Pirrolina Carboxilato Redutases/metabolismo , delta-1-Pirrolina-5-Carboxilato Redutase
6.
J Cell Biochem ; 111(4): 872-80, 2010 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-20665543

RESUMO

The level of circulating endotoxin is related to the severity of cardiovascular disease. One of the indexes for the prognosis of cardiovascular disease is the plasma aldosterone level. Recently, the Toll-like receptors (TLRs), lipopolysaccharide (LPS)-regulated receptors, were found not only to mediate the inflammatory response but also to be important in the adrenal stress response. Whether LPS via TLRs induced aldosterone production in adrenal zona glomerulosa (ZG) cells was not clear. Our results suggest that LPS-induced aldosterone secretion in a time- and dose-dependent manner and via TLR2 and TLR4 signaling pathway. Administration of LPS can enhance steroidogenesis enzyme expression such as scavenger receptor-B1 (SR-B1), steroidogenic acute regulatory protein (StAR) and P450 side chain cleavage (P450scc) enzyme. LPS-induced SR-B1 and StAR protein expression are abolished by TLR2 blocker. Furthermore, we demonstrated that phosphorylation of Akt was elevated by LPS treatment and reduced by TLR2 blockers, TLR4 blockers, and LY294002 (PI(3)K inhibitor). Those inhibitors of PI(3)K/Akt pathways also abolish LPS-induced aldosterone secretion and SR-B1 protein level. In conclusion, LPS-induced aldosterone production and SR-B1 proteins expression are through the TLR2 and TLR4 related PI(3)K/Akt pathways in adrenal ZG cells.


Assuntos
Aldosterona/biossíntese , Lipopolissacarídeos/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo , Zona Glomerulosa/citologia , Animais , Enzima de Clivagem da Cadeia Lateral do Colesterol/metabolismo , Masculino , Modelos Biológicos , Fosfoproteínas/metabolismo , Fosforilação/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Receptores Depuradores Classe B/metabolismo , Transdução de Sinais/efeitos dos fármacos
7.
Cells ; 9(5)2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32370022

RESUMO

Impairment of the ubiquitin-proteasome-system (UPS) and autophagy causing cytoplasmic aggregation of ubiquitin andp62 have been implicated in the pathogenesis of most neurodegenerative disorders, yet, they have not been fully elucidated in leukodystrophies. The relationship among impairment of UPS, autophagy, and globoid cell leukodystrophy (GLD), one of the most common demyelinating leukodystrophies, is clarified in this study. We examined the ubiquitin and autophagy markers in the brains of twitcher mice, a murine model of infantile GLD, and in human oligodendrocytes incubated with psychosine. Immunohistochemical examinations showed spatiotemporal accumulation of ubiquitin- and p62-aggregates mainly in the white matter of brain and spinal cord at disease progression. Western blot analysis demonstrated a significant accumulation of ubiquitin, p62, and LC3-II in insoluble fraction in parallel with progressive demyelination and neuroinflammation in twitcher brains. In vitro study validated a dose- and time-dependent cytotoxicity of psychosine upon autophagy and UPS machinery. Inhibition of autophagy and UPS exacerbated the accumulation of insoluble ubiquitin, p62, and LC3-II proteins mediated by psychosine cytotoxicity as well as increased cytoplasmic deposition of ubiquitin- and p62-aggregates, and accumulation of autophagosomes and autolysosomes. Further, the subsequent accumulation of reactive oxygen species and reduction of mitochondrial respiration led to cell death. Our studies validate the impairment of proteasome and autophagy underlying the pathogenesis of GLD. These findings provide a novel insight into pathogenesis of GLD and suggest a specific pathomechanism as an ideal target for therapeutic approaches.


Assuntos
Autofagia , Leucodistrofia de Células Globoides/patologia , Complexo de Endopeptidases do Proteassoma/metabolismo , Animais , Autofagossomos/efeitos dos fármacos , Autofagossomos/metabolismo , Encéfalo/metabolismo , Encéfalo/patologia , Linhagem Celular , Respiração Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Camundongos Endogâmicos C57BL , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Degeneração Neural/patologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Oligodendroglia/efeitos dos fármacos , Oligodendroglia/metabolismo , Agregados Proteicos/efeitos dos fármacos , Psicosina/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Proteína Sequestossoma-1/metabolismo , Fatores de Tempo , Ubiquitina/metabolismo , Substância Branca/patologia
8.
Cancers (Basel) ; 12(8)2020 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-32764489

RESUMO

Synthetic Zfra4-10 and WWOX7-21 peptides strongly suppress cancer growth in vivo. Hypothetically, Zfra4-10 binds to the membrane Hyal-2 of spleen Z cells and activates the Hyal-2/WWOX/SMAD4 signaling for cytotoxic Z cell activation to kill cancer cells. Stimulation of membrane WWOX in the signaling complex by a WWOX epitope peptide, WWOX7-21, is likely to activate the signaling. Here, mice receiving Zfra4-10 or WWOX7-21 peptide alone exhibited an increased binding of endogenous tumor suppressor WWOX with ERK, C1qBP, NF-κB, Iba1, p21, CD133, JNK1, COX2, Oct4, and GFAP in the spleen, brain, and/or lung which led to cancer suppression. However, when in combination, Zfra4-10 and WWOX7-21 reduced the binding of WWOX with target proteins and allowed tumor growth in vivo. In addition to Zfra4-10 and WWOX7-21 peptides, stimulating the membrane Hyal-2/WWOX complex with Hyal-2 antibody and sonicated hyaluronan (HAson) induced Z cell activation for killing cancer cells in vivo and in vitro. Mechanistically, Zfra4-10 binds to membrane Hyal-2, induces dephosphorylation of WWOX at pY33 and pY61, and drives Z cell activation for the anticancer response. Thus, Zfra4-10 and WWOX7-21 peptides, HAson, and the Hyal-2 antibody are of therapeutic potential for cancer suppression.

9.
Cells ; 8(1)2019 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-30658448

RESUMO

Dysfunction of mitochondria causes defects in oxidative phosphorylation system (OXPHOS) and increased production of reactive oxygen species (ROS) triggering the activation of the cell death pathway that underlies the pathogenesis of aging and various diseases. The process of autophagy to degrade damaged cytoplasmic components as well as dysfunctional mitochondria is essential for ensuring cell survival. We analyzed the role of autophagy inpatient-specific induced pluripotent stem (iPS) cells generated from fibroblasts of patients with mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) with well-characterized mitochondrial DNA mutations and distinct OXPHOS defects. MELAS iPS cells recapitulated the pathogenesis of MELAS syndrome, and showed an increase of autophagy in comparison with its isogenic normal counterpart, whereas mitophagy is very scarce at the basal condition. Our results indicated that the existence of pathogenic mtDNA alone in mitochondrial disease was not sufficient to elicit the degradation of dysfunctional mitochondria. Nonetheless, oxidative insults induced bulk macroautophagy with the accumulation of autophagosomes and autolysosomes upon marked elevation of ROS, overload of intracellular calcium, and robust depolarization of mitochondrial membrane potential, while mitochondria respiratory function was impaired and widespread mitophagy compromised cell viability. Collectively, our studies provide insights into the dysfunction of autophagy and activation of mitophagy contributing to the pathological mechanism of mitochondrial disease.


Assuntos
Autofagia/genética , DNA Mitocondrial/genética , Células-Tronco Pluripotentes Induzidas/patologia , Doenças Mitocondriais/genética , Doenças Mitocondriais/patologia , Mitofagia/genética , Modelos Biológicos , Mutação/genética , Trifosfato de Adenosina/metabolismo , Autofagossomos/metabolismo , Biomarcadores/metabolismo , Cálcio/metabolismo , Membrana Celular/metabolismo , Respiração Celular , Sobrevivência Celular , Citoplasma/metabolismo , Metabolismo Energético , Fibroblastos/metabolismo , Fibroblastos/patologia , Humanos , Lisossomos/metabolismo , Síndrome MELAS/genética , Síndrome MELAS/patologia , Potencial da Membrana Mitocondrial , Oxirredução , Espécies Reativas de Oxigênio/metabolismo
11.
J Formos Med Assoc ; 107(12): 937-44, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19129054

RESUMO

BACKGROUND/PURPOSE: Detection of fever has become an essential step in identifying patients who may have severe acute respiratory syndrome (SARS) or avian influenza. This study evaluated infrared thermography (IRT) and compared the influence of different imagers, ambient temperature discrepancy, and the distance between the subject and imager. METHODS: IRT-digital infrared thermal imaging (IRT-DITI), thermoguard, and ear drum IRT were used for visitors to Municipal Wang Fang Hospital, Taipei, Taiwan. The McNemar and Chi-squared test, standard Pearson correlation, ANOVA, intraclass correlation coefficient (ICC), and receiver operating characteristic curve (ROC) analysis were used to calculate the alarm temperature for each imager. RESULTS: A total of 1032 subjects were recruited. Different distances and ambient temperature discrepancy had a significant influence on thermoguard, and lateral and frontal view DITI. By ICC analysis, a significant difference was found at 10 m distance between ear drum IRT and thermoguard (r = 0.45), lateral view DITI (r = 0.37), and frontal view DITI (r = 0.44). With ROC analysis, the optimal preset cut-off temperatures for the different imagers were: 36.05 degrees C for thermoguard (area under the curve [AUC], 0.716), 36.25 degrees C for lateral view DITI (AUC, 0.801), and 36.25 degrees C for frontal view DITI (AUC, 0.812). CONCLUSION: The temperature readings obtained by IRT may be used as a proxy for core temperature. An effective IRT system with a strict operating protocol can be rapidly implemented at the entrance of a hospital during SARS or avian influenza epidemics.


Assuntos
Temperatura Corporal/fisiologia , Febre/diagnóstico , Influenza Humana/diagnóstico , Raios Infravermelhos , Programas de Rastreamento/métodos , Síndrome Respiratória Aguda Grave/diagnóstico , Termografia/instrumentação , Diagnóstico Diferencial , Surtos de Doenças , Desenho de Equipamento , Febre/fisiopatologia , Humanos , Influenza Humana/epidemiologia , Curva ROC , Síndrome Respiratória Aguda Grave/epidemiologia , Taiwan/epidemiologia
12.
Front Neurosci ; 12: 563, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30158849

RESUMO

Homozygous null mutation of tumor suppressor WWOX/Wwox gene leads to severe neural diseases, metabolic disorders and early death in the newborns of humans, mice and rats. WWOX is frequently downregulated in the hippocampi of patients with Alzheimer's disease (AD). In vitro analysis revealed that knockdown of WWOX protein in neuroblastoma cells results in aggregation of TRAPPC6AΔ, TIAF1, amyloid ß, and Tau in a sequential manner. Indeed, TRAPPC6AΔ and TIAF1, but not tau and amyloid ß, aggregates are present in the brains of healthy mid-aged individuals. It is reasonable to assume that very slow activation of a protein aggregation cascade starts sequentially with TRAPPC6AΔ and TIAF1 aggregation at mid-ages, then caspase activation and APP de-phosphorylation and degradation, and final accumulation of amyloid ß and Tau aggregates in the brains at greater than 70 years old. WWOX binds Tau-hyperphosphorylating enzymes (e.g., GSK-3ß) and blocks their functions, thereby supporting neuronal survival and differentiation. As a neuronal protective hormone, 17ß-estradiol (E2) binds WWOX at an NSYK motif in the C-terminal SDR (short-chain alcohol dehydrogenase/reductase) domain. In this review, we discuss how WWOX and E2 block protein aggregation during neurodegeneration, and how a 31-amino-acid zinc finger-like Zfra peptide restores memory loss in mice.

13.
Aging Dis ; 9(6): 1043-1057, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30574417

RESUMO

Aging is a complex biological process. A study of pyrroline-5-carboxylate reductase 1 (PYCR1) deficiency, which causes a progeroid syndrome, may not only shed light on its genetic contribution to autosomal recessive cutis laxa (ARCL) but also help elucidate the functional mechanisms associated with aging. In this study, we used RNA-Seq technology to examine gene expression changes in primary skin fibroblasts from healthy controls and patients with PYCR1 mutations. Approximately 22 and 32 candidate genes were found to be up- and downregulated, respectively, in fibroblasts from patients. Among the downregulated candidates in fibroblasts with PYCR1 mutations, a strong reduction in the expression of 17 genes (53.1%) which protein products are localized in the extracellular space was detected. These proteins included several important ECM components, periostin (POSTN), elastin (ELN), and decorin (DCN); genetic mutations in these proteins are associated with different phenotypes of aging, such as cutis laxa and joint and dermal manifestations. The differential expression of ten selected extracellular space genes was further validated using quantitative RT-PCR. Ingenuity Pathway Analysis revealed that some of the affected genes may be associated with cardiovascular system development and function, dermatological diseases and conditions, and cardiovascular disease. POSTN, one of the most downregulated gene candidates in affected individuals, is a matricellular protein with pivotal functions in heart valvulogenesis, skin wound healing, and brain development. Perturbation of PYCR1 expression revealed that it is positively correlated with the POSTN levels. Taken together, POSTN might be one of the key molecules that deserves further investigation for its role in this progeroid neurocutaneous syndrome.

14.
J Neurosci ; 26(13): 3444-53, 2006 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-16571751

RESUMO

Although stem cell-based treatments for stroke and other neurodegenerative diseases have advanced rapidly, there are still few clinical treatments available. In this study, rats receiving intracerebral peripheral blood hematopoietic stem cell (CD34+) (PBSC) transplantation showed much more improvement in neurological function after chronic cerebral ischemia in comparison with vehicle-treated control rats. Using laser-scanning confocal microscopy, implanted PBSCs were seen to differentiate into glial cells [GFAP+ (glial fibrillary acidic protein-positive)], neurons [Nestin+, MAP-2+ (microtubule-associated protein 2-positive), Neu-N+ (neuronal nuclear antigen-positive)], and vascular endothelial cells [vWF+ (von Willebrand factor-positive)], thereby enhancing neuroplastic effects in the ischemic brain. Cortical neuronal activity, as evaluated by 1H-MRS (proton magnetic resonance spectroscopy), also increased considerably in PBSC-treated rats compared with a vehicle-treated control group. In addition, PBSC implantation promoted the formation of new vessels, thereby increasing the local cortical blood flow in the ischemic hemisphere. These observations may be explained by the involvement of stem cell-derived macrophage/microglial cells, and beta1 integrin expression, which might enhance this angiogenic architecture over the ischemic brain. Furthermore, quantitative reverse transcription-PCR analysis showed significantly increased modulation of neurotrophic factor expression in the ischemic hemisphere of the PBSC-transplanted rats compared with vehicle-treated control rats. Thus, intracerebral PBSC transplantation might have potential as a therapeutic strategy for treating cerebrovascular diseases.


Assuntos
Antígenos CD34/metabolismo , Integrina beta1/metabolismo , Neovascularização Fisiológica , Plasticidade Neuronal , Transplante de Células-Tronco/métodos , Acidente Vascular Cerebral/metabolismo , Acidente Vascular Cerebral/cirurgia , Animais , Encéfalo/metabolismo , Encéfalo/cirurgia , Diferenciação Celular , Doença Crônica , Células-Tronco Hematopoéticas/metabolismo , Células-Tronco Hematopoéticas/patologia , Masculino , Ratos , Ratos Sprague-Dawley , Acidente Vascular Cerebral/patologia , Resultado do Tratamento
15.
Oncotarget ; 8(43): 73627-73639, 2017 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-29088732

RESUMO

Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome is most commonly caused by the A3243G mutation of mitochondrial DNA. The capacity to utilize fatty acid or glucose as a fuel source and how such dynamic switches of metabolic fuel preferences and transcriptional modulation of adaptive mechanism in response to energy deficiency in MELAS syndrome have not been fully elucidated. The fibroblasts from patients with MELAS syndrome demonstrated a remarkable deficiency of electron transport chain complexes I and IV, an impaired cellular biogenesis under glucose deprivation, and a decreased ATP synthesis. In situ analysis of the bioenergetic properties of MELAS cells demonstrated an attenuated fatty acid oxidation that concomitantly occurred with impaired mitochondrial respiration, while energy production was mostly dependent on glycolysis. Furthermore, the transcriptional modulation was mediated by the AMP-activated protein kinase (AMPK) signaling pathway, which activated its downstream modulators leading to a subsequent increase in glycolytic flux through activation of pyruvate dehydrogenase. In contrast, the activities of carnitine palmitoyltransferase for fatty acid oxidation and acetyl-CoA carboxylase-1 for fatty acid synthesis were reduced and transcriptional regulation factors for biogenesis were not altered. These results provide novel information that MELAS cells lack the adaptive mechanism to switch fuel source from glucose to fatty acid, as glycolysis rates increase in response to energy deficiency. The aberrant secondary cellular responses to disrupted metabolic homeostasis mediated by AMPK signaling pathway may contribute to the development of the clinical phenotype.

16.
J Neurosci ; 25(39): 8967-77, 2005 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-16192387

RESUMO

Prion diseases are induced by pathologically misfolded prion protein (PrPSc), which recruit normal sialoglycoprotein PrPC by a template-directed process. In this study, we investigated the expression of PrPC in a rat model of cerebral ischemia to more fully understand its physiological role. Immunohistochemical analysis demonstrated that PrPC-immunoreactive cells increased significantly in the penumbra of ischemic rat brain compared with the untreated brain. Western blot analysis showed that PrPC protein expression increased in ischemic brain tissue in a time-dependent manner. In addition, PrPC protein expression was seen to colocalize with neuron, glial, and vascular endothelial cells in the penumbric region of the ischemic brain. Overexpression of PrPC by injection of rAd (replication-defective recombinant adenoviral)-PGK (phosphoglycerate kinase)-PrPC-Flag into ischemic rat brain improved neurological behavior and reduced the volume of cerebral infarction, which is supportive of a role for PrPC in the neuroprotective adaptive cellular response to ischemic lesions. Concomitant upregulation of PrPC and activated extracellular signal-regulated kinase (ERK1/2) under hypoxia-reoxygenation in primary cortical cultures was shown to be dependent on ERK1/2 phosphorylation. During hypoxia-reoxygenation, mouse neuroblastoma cell line N18 cells transfected with luciferase rat PrPC promoter reporter constructs, containing the heat shock element (HSE), expressed higher luciferase activities (3- to 10-fold) than those cells transfected with constructs not containing HSE. We propose that HSTF-1 (hypoxia-activated transcription factor), phosphorylated by ERK1/2, may in turn interact with HSE in the promoter of PrPC resulting in gene expression of the prion gene. In summary, we conclude that upregulation of PrPC expression after cerebral ischemia and hypoxia exerts a neuroprotective effect on injured neural tissue. This study suggests that PrPC has physiological relevance to cerebral ischemic injury and could be useful as a therapeutic target for the treatment of cerebral ischemia.


Assuntos
Isquemia Encefálica/patologia , Isquemia Encefálica/fisiopatologia , Marcação de Genes , Fármacos Neuroprotetores/metabolismo , Proteínas PrPC/metabolismo , Adenoviridae/genética , Animais , Apoptose , Encéfalo/metabolismo , Encéfalo/patologia , Isquemia Encefálica/complicações , Isquemia Encefálica/metabolismo , Células Cultivadas , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Infarto Cerebral/patologia , Modelos Animais de Doenças , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Marcação de Genes/métodos , Vetores Genéticos , Humanos , Hipóxia/metabolismo , Masculino , Sistema Nervoso/fisiopatologia , Oxigênio/farmacologia , Proteínas PrPC/genética , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Acidente Vascular Cerebral/etiologia , Distribuição Tecidual
17.
Surg Neurol ; 66 Suppl 2: S14-9, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17071249

RESUMO

BACKGROUND: Data pertaining to head injuries in adolescents in Taiwan are scarce. The purpose of this study was to investigate the trend and pattern of head injuries in adolescents in both urban and rural areas in Taiwan. METHODS: We collected data from major hospitals in the urban (20) and in the rural (4) areas of Taiwan for a period of 3 years. Data were obtained from the Head Injury Registry, a 10-year electronic database of head injury in Taiwan. The inpatient medical records of adolescents with head injury were thoroughly reviewed. Severity of head injury was classified by the GCS score, and patient outcome at discharge from hospital was measured by the Glasgow Outcome Scale. Differences and correlation between study groups (13-15 and 16-18 years old) in the urban and rural areas were examined using 2-tailed t and chi(2) tests. RESULTS: A total of 469 head injury cases in the urban area and 131 in the rural area were identified. Traffic accidents were the major cause of head injury, and motorcycles were the most predominant vehicles causing traffic accidents in both urban and rural areas. Intracranial hemorrhages were the most prevalent injury pattern in the study population. In both urban and rural areas, the severities of injury were not significantly different (P=.184), but the outcomes at discharge were significantly better in urban areas (P=.032). The correlation between the initial GCS and outcomes in both areas was significant (P<.001). Craniotomy was performed more frequently in the rural area than in the urban area (15.3% vs 7.2%). The mean hospital stay was shorter in the latter than in the former (P<.001). Education on helmet use, input of neurosurgical staff, and facility and emergency medical transportation service of head-injured patients following guidelines proposed by the WFNS are crucial for head injury and better control in rural areas. CONCLUSIONS: The causes, patterns, and outcomes of head injury were statistically different between the 2 age groups of adolescents in urban and rural areas. Further studies on adolescent head injury are necessary.


Assuntos
Lesões Encefálicas/epidemiologia , Saúde da População Rural/estatística & dados numéricos , Saúde da População Urbana/estatística & dados numéricos , Adolescente , Lesões Encefálicas/complicações , Lesões Encefálicas/terapia , Feminino , Escala de Coma de Glasgow , Humanos , Tempo de Internação , Masculino , Sistema de Registros , Distribuição por Sexo , Taiwan/epidemiologia , Resultado do Tratamento
18.
Surg Neurol ; 66 Suppl 2: S32-6, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17071253

RESUMO

BACKGROUND: Patients suffering head injury in remote islands of Taiwan, which have a shortage of manpower and facilities, depend on EAMS for prompt and definitive treatment. Emergency air medical services are becoming an increasingly important issue in improving the quality of primary care and avoiding medicolegal problems. The purpose of this study was to investigate the characteristics of patients with head injury and use of EAMS. METHODS: We reviewed all patients, especially head injury transported by air ambulance from a remote island, Kinmen (400 km from Taiwan Main Island), from January 2001 to December 2003. Data were collected with regard to demographics, disease classification, mechanism of injury, severity of head injury, ventilator use, and mortality rate. RESULTS: A total of 215 patients were transferred, of whom 57 (27%) had head injury. The mean age of patients was 48.6 +/- 23.8 years. Males accounted for 72% of the cases (male/female ratio, 2.6:1). Motor-vehicle accidents were the most common mechanism of injury (68%). There were 21 (37%), 20 (35%), and 16 (28%) patients in the minor, moderate, and severe head-injury groups, respectively. Nineteen patients (33%) received mechanical ventilation. The overall mortality rate was 14 % (8/57). In the severe head-injury group, the mortality rate was 44% (7/16). CONCLUSIONS: The higher incidence of head injury (26.5%) in EAMS than in ground transportation (19.8%) suggests that preflight assessment and in-flight management of patients conducted by an experienced escort team following guidelines for head injury in EAMS are a very important issue.


Assuntos
Resgate Aéreo/estatística & dados numéricos , Lesões Encefálicas/epidemiologia , Adolescente , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Lesões Encefálicas/terapia , Criança , Pré-Escolar , Feminino , Escala de Coma de Glasgow , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Distribuição por Sexo , Taiwan/epidemiologia , Resultado do Tratamento
19.
Front Cell Dev Biol ; 4: 141, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27999774

RESUMO

Hyaluronidase HYAL-2 is a membrane-anchored protein and also localizes, in part, in the lysosome. Recent study from animal models revealed that both HYAL-1 and HYAL-2 are essential for the metabolism of hyaluronan (HA). Hyal-2 deficiency is associated with chronic thrombotic microangiopathy with hemolytic anemia in mice due to over accumulation of high molecular size HA. HYAL-2 is essential for platelet generation. Membrane HYAL-2 degrades HA bound by co-receptor CD44. Also, in a non-canonical signal pathway, HYAL-2 serves as a receptor for transforming growth factor beta (TGF-ß) to signal with downstream tumor suppressors WWOX and SMAD4 to control gene transcription. When SMAD4 responsive element is overly driven by the HYAL-2-WWOX-SMAD4 signaling complex, cell death occurs. When rats are subjected to traumatic brain injury, over accumulation of a HYAL-2-WWOX complex occurs in the nucleus to cause neuronal death. HA induces the signaling of HYAL-2-WWOX-SMAD4 and relocation of the signaling complex to the nucleus. If the signaling complex is overexpressed, bubbling cell death occurs in WWOX-expressing cells. In addition, a small synthetic peptide Zfra (zinc finger-like protein that regulates apoptosis) binds membrane HYAL-2 of non-T/non-B spleen HYAL-2+ CD3- CD19- Z lymphocytes and activates the cells to generate memory anticancer response against many types of cancer cells in vivo. Whether the HYAL-2-WWOX-SMAD4 signaling complex is involved is discussed. In this review and opinion article, we have updated the current knowledge of HA, HYAL-2 and WWOX, HYAL-2-WWOX-SMAD4 signaling, bubbling cell death, and Z cell activation for memory anticancer response.

20.
Ann N Y Acad Sci ; 1042: 48-54, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15965044

RESUMO

Brain single photon emission computed tomography (SPECT) studies were conducted in three patients with A3243G mutation of the mitochondrial (mt) DNA tRNA. All were born to mothers suffering from chronic progressive external ophthalmoplegia (CPEO) with the same A3243G point mutation of the mtDNA tRNA. The first case manifested clinically with MELAS, the second case manifested with CPEO, and third case was characterized by recurrent migraine-like headache, tremor, and epilepsy. Brain SPECT of all patients, regardless of whether they had or had not suffered from stroke-like episodes, showed multiple areas of asymmetrical decreased perfusion, particularly in the posterior and lateral head regions, especially the temporal lobes. Crossed-cerebellar diaschisis may occur. Conventional brain magnetic resonance images failed to show some of the lesions. Decreased regional cerebral blood flow, rather than previously proposed hyperemia, is likely to be the cause. We conclude that mitochondrial vasculopathy with regional cerebral hypoperfusion may be seen on brain SPECT in patients with mitochondrial disorders and A3243G mutations, regardless of whether they have or have not suffered from stroke-like episodes.


Assuntos
Adenosina/genética , Encéfalo/metabolismo , Encéfalo/patologia , DNA Mitocondrial/genética , RNA de Transferência/genética , Adolescente , Adulto , Encéfalo/irrigação sanguínea , Humanos , Síndrome MELAS/diagnóstico , Síndrome MELAS/genética , Síndrome MELAS/patologia , Masculino , Transtornos de Enxaqueca/genética , Transtornos de Enxaqueca/patologia , Mutação/genética , Tomografia Computadorizada de Emissão de Fóton Único
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