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1.
Ther Adv Med Oncol ; 14: 17588359221122729, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36312814

RESUMO

Immune checkpoint inhibitors (ICIs) are the current guideline recommended treatment for many malignancies considered to be terminal. Despite considerable advances, their utility remains limited, and the field requires synergistic partners to further improve outcomes. Oncolytic viruses (OV) are emerging as contenders for the role of the synergistic agent of choice due to their multi-mechanistic effect on activating the tumor 'cold' immune microenvironment. Herpes simplex virus 1, a naturally selective OV, is the most advanced virotherapeutic compound in clinical applications for use in combination with ICI. We here present the case of a 72 year-old patient with a heavily pre-treated, advanced maxillary sinus squamous cell cancer with distant metastases who developed complete response (CR) with only three administrations of a programmed death 1 inhibitor after treatment interference by a severe herpes zoster infection, based on the related alpha-herpesvirus varicella zoster virus (VZV). This exceptional response has been followed and confirmed with imaging studies over more than 5 years. Although the patient had several favorable predictors for response to immunotherapy, we reason that the exceptional response may in part be secondary to the serendipitous VZV infection. Documented cases of cancer patients that achieved CR after few administrations of treatment with ICI are rare, with most reporting follow up of just over 1 year or less. In this case, it is conceivable that the interference of the infection with VZV, soon after the start of immunotherapy with ICI, led to a lasting antitumor immunity and sustained CR. This hypothesis is supported by the concept of 'oncolytic immunotherapy' which is reviewed in this manuscript. In addition, persistence of a TP53 mutation found in a liquid biopsy, despite clinical and radiologic remission, is discussed.

2.
Neurol Neuroimmunol Neuroinflamm ; 6(6): e631, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31611269

RESUMO

OBJECTIVE: To test the hypothesis that patients with amyotrophic lateral sclerosis (ALS) inheriting the common interleukin 6 receptor (IL6R) coding variant (Asp358Ala, rs2228145, C allele) have associated increases in interleukin 6 (IL6) and IL6R levels in serum and CSF and faster disease progression than noncarriers. METHODS: An observational, case-control study of paired serum and CSF of 47 patients with ALS, 46 healthy, and 23 neurologic disease controls from the Northeastern ALS Consortium Biofluid Repository (cohort 1) was performed to determine serum levels of IL6, sIL6R, and soluble glycoprotein 130 and compared across groups and IL6R genotype. Clinical data regarding disease progression from a separate cohort of 35 patients with ALS from the Wake Forest ALS Center (cohort 2) were used to determine change in ALSFRS-R scores by genotype. RESULTS: Patients with ALS had increased CSF IL6 levels compared with healthy (p < 0.001) and neurologic (p = 0.021) controls. Patients with ALS also had increased serum IL6 compared with healthy (p = 0.040) but not neurologic controls. Additive allelic increases in serum IL6R were observed in all groups (average increase of 52% with the presence of the IL6R C allele; p < 0.001). However, only subjects with ALS had significantly increased CSF sIL6R levels compared with controls (p < 0.001). When compared across genotypes, only patients with ALS inheriting the IL6R C allele exhibit increased CSF IL6. ALSFRS-R scores decreased more in patients with ALS with the IL6R C allele than in those without (p = 0.019). CONCLUSIONS: Theses results suggest that for individuals inheriting the IL6R C allele, the cytokine exerts a disease- and location-specific role in ALS. Follow-up, prospective studies are necessary, as this subgroup of patients may be identified as ideally responsive to IL6 receptor-blocking therapies.


Assuntos
Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/metabolismo , Esclerose Lateral Amiotrófica/fisiopatologia , Progressão da Doença , Interleucina-6/metabolismo , Receptores de Interleucina-6/genética , Receptores de Interleucina-6/metabolismo , Adulto , Idoso , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
3.
Radiat Res ; 192(2): 145-158, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31166846

RESUMO

While cutaneous radiation injury (CRI) is generally referenced as a consequence of a nuclear attack, it can also be caused by less dangerous events such as the use of dirty bombs, industrial radiological accidents, or accidental overexposure of beta (ß) particle or gamma (γ) radiation sources in medical procedures. Although the gross clinical consequences of these injuries have been well documented, relatively little is known about the molecular changes underlying the progression of pathology. Here we describe a porcine model of cutaneous radiation injury after skin was exposed to strontium-90 b particle at doses of 16-42 Gy and characterize the anatomical and molecular changes over 70 days. The results show that irradiated sites displayed dosedependent increases in erythema and moist desquamation that peaked between days 35 and 42. Dose-dependent histopathological changes were observed, with higher doses exhibiting increased inflammation and epidermal hyperplasia beyond day 35. Furthermore, immunohistochemistry showed that exposure to 37 Gy ß-particle radiation decreased epidermal cell proliferation and desmosomal junction proteins at day 70, suggesting compromised epidermal integrity. Metabolomic analysis of biopsies revealed dose- and time-dependent changes as high as 252-fold in several metabolites not previously linked to CRI. These alterations were seen in pathways reflecting protein degradation, oxidative stress, eicosanoid production, collagen matrix remodeling, mitochondrial stress, cell membrane composition and vascular disruption. Taken together, these data show that exposure to high doses of ß particle damaged the molecular processes underlying skin integrity to a greater extent and for a longer period of time than has been shown previously. These findings further understanding of radiation-induced skin injury and serve as a foundation for the development and testing of potential therapeutics to treat CRI.


Assuntos
Partículas beta/efeitos adversos , Pele/lesões , Pele/efeitos da radiação , Animais , Proliferação de Células/efeitos da radiação , Relação Dose-Resposta à Radiação , Feminino , Pele/metabolismo , Pele/patologia , Suínos , Transcriptoma/efeitos da radiação
4.
Biomed Phys Eng Express ; 6(1): 015007, 2019 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-33438595

RESUMO

PURPOSE: Radiation skin injuries are difficult to quantitatively assess. Various scoring scales exist based on visual images and can be used in quantitative form for histological scoring. As an alternative to human scoring systems, an automated, quantitative system is proposed to provide unbiased scoring of radiation skin injury biopsy samples, with comparisons to human-based scoring systems. MATERIALS AND METHODS: A unique algorithm was developed and tested on a sample pool obtained from in-vivo beta radiation experiments with a porcine model. The grading results achieved by the developed algorithm and those provided by an expert histopathologist are compared. RESULTS: The extent of the epidermal necrosis is quantified in terms of the number of dead cells and their respective distribution across the length of the samples. The accuracy of the grading performed by the automated algorithm is comparable to that of a trained histopathologist, as demonstrated by statistically significant difference between the grades. CONCLUSIONS: This study demonstrates the feasibility of the proposed method as a potential tool designed to aid in the histopathological analysis of the tissues affected by beta radiation exposure. An expanded study with a larger sample pool is recommended to further improve the accuracy of the proposed algorithm.


Assuntos
Partículas beta/efeitos adversos , Lesões Experimentais por Radiação/patologia , Pele/patologia , Pele/efeitos da radiação , Algoritmos , Animais , Automação , Estudos de Viabilidade , Feminino , Necrose , Patologistas , Suínos
5.
Leuk Lymphoma ; 59(8): 1871-1877, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29252084

RESUMO

High-dose glucocorticoids such as prednisone are combined with cytotoxic chemotherapy in the R-CHOP or dose adjusted R-EPOCH regimens used for non-Hodgkin lymphoma (NHL). In this retrospective study, our primary objective was to evaluate the incidence of hyperglycemia during first-line R-CHOP or DA-EPOCH-R. The secondary objectives were to evaluate the incidence of chemotherapy alteration and overall survival in those with and without hyperglycemia. One hundred and sixty patients were eligible. We found that 47% of all patients had at least one hyperglycemic episode and hyperglycemia was associated with chemotherapy alteration (p = .028). Multivariate analysis revealed international prognostic index (IPI) ≥ 3 (p = .045) and chemotherapy alteration (p = .001) were associated with decreased overall survival. We conclude that hyperglycemia is common during first-line NHL treatment with R-CHOP or DA-EPOCH-R, even in the absence of known diabetes and is associated with alterations of chemotherapy. Baseline pre-PET scan fasting blood glucose of 100 mg/dL or higher may predict hyperglycemia during therapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Hiperglicemia/diagnóstico , Linfoma não Hodgkin/tratamento farmacológico , Idoso , Anticorpos Monoclonais Murinos/administração & dosagem , Anticorpos Monoclonais Murinos/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Glicemia/análise , Ciclofosfamida/administração & dosagem , Ciclofosfamida/efeitos adversos , Doxorrubicina/administração & dosagem , Doxorrubicina/efeitos adversos , Etoposídeo/administração & dosagem , Etoposídeo/efeitos adversos , Feminino , Humanos , Hiperglicemia/sangue , Hiperglicemia/induzido quimicamente , Estimativa de Kaplan-Meier , Linfoma não Hodgkin/sangue , Masculino , Pessoa de Meia-Idade , Prednisona/administração & dosagem , Prednisona/efeitos adversos , Estudos Retrospectivos , Rituximab/administração & dosagem , Rituximab/efeitos adversos , Vincristina/administração & dosagem , Vincristina/efeitos adversos
6.
Theranostics ; 7(11): 2914-2923, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28824725

RESUMO

Background: Cancers related to tobacco use and African-American ancestry are under-characterized by genomics. This gap in precision oncology research represents a major challenge in the health disparities in the United States. Methods: The Precision Oncology trial at the Wake Forest Baptist Comprehensive Cancer Center enrolled 431 cancer patients from March 2015 to May 2016. The composition of these patients consists of a high representation of tobacco-related cancers (e.g., lung, colorectal, and bladder) and African-American ancestry (13.5%). Tumors were sequenced to identify mutations to gain insight into genetic alterations associated with smoking and/or African-American ancestry. Results: Tobacco-related cancers exhibit a high mutational load. These tumors are characterized by high-frequency mutations in TP53, DNA damage repair genes (BRCA2 and ATM), and chromatin remodeling genes (the lysine methyltransferases KMT2D or MLL2, and KMT2C or MLL3). These tobacco-related cancers also exhibit augmented tumor heterogeneities. Smoking related genetic mutations were validated by The Cancer Genome Atlas dataset that includes 2,821 cases with known smoking status. The Wake Forest and The Cancer Genome Atlas cohorts (431 and 7,991 cases, respectively) revealed a significantly increased mutation rate in the TP53 gene in the African-American subgroup studied. Both cohorts also revealed 5 genes (e.g. CDK8) significantly amplified in the African-American population. Conclusions: These results provide strong evidence that tobacco is a major cause of genomic instability and heterogeneity in cancer. TP53 mutations and key oncogene amplifications emerge as key factors contributing to cancer outcome disparities among different racial/ethnic groups.


Assuntos
Neoplasias Colorretais/patologia , Neoplasias Pulmonares/patologia , Mutação , Fumar Tabaco/efeitos adversos , Neoplasias da Bexiga Urinária/patologia , Negro ou Afro-Americano , Humanos , Patologia Molecular , Análise de Sequência de DNA , Proteína Supressora de Tumor p53/genética , População Branca
7.
J Hematol Oncol ; 10(1): 100, 2017 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-28472989

RESUMO

BACKGROUND: Solid tumors residing in tissues and organs leave footprints in circulation through circulating tumor cells (CTCs) and circulating tumor DNAs (ctDNA). Characterization of the ctDNA portraits and comparison with tumor DNA mutational portraits may reveal clinically actionable information on solid tumors that is traditionally achieved through more invasive approaches. METHODS: We isolated ctDNAs from plasma of patients of 103 lung cancer and 74 other solid tumors of different tissue origins. Deep sequencing using the Guardant360 test was performed to identify mutations in 73 clinically actionable genes, and the results were associated with clinical characteristics of the patient. The mutation profiles of 37 lung cancer cases with paired ctDNA and tumor genomic DNA sequencing were used to evaluate clonal representation of tumor in circulation. Five lung cancer cases with longitudinal ctDNA sampling were monitored for cancer progression or response to treatments. RESULTS: Mutations in TP53, EGFR, and KRAS genes are most prevalent in our cohort. Mutation rates of ctDNA are similar in early (I and II) and late stage (III and IV) cancers. Mutation in DNA repair genes BRCA1, BRCA2, and ATM are found in 18.1% (32/177) of cases. Patients with higher mutation rates had significantly higher mortality rates. Lung cancer of never smokers exhibited significantly higher ctDNA mutation rates as well as higher EGFR and ERBB2 mutations than ever smokers. Comparative analysis of ctDNA and tumor DNA mutation data from the same patients showed that key driver mutations could be detected in plasma even when they were present at a minor clonal population in the tumor. Mutations of key genes found in the tumor tissue could remain in circulation even after frontline radiotherapy and chemotherapy suggesting these mutations represented resistance mechanisms. Longitudinal sampling of five lung cancer cases showed distinct changes in ctDNA mutation portraits that are consistent with cancer progression or response to EGFR drug treatment. CONCLUSIONS: This study demonstrates that ctDNA mutation rates in the key tumor-associated genes are clinical parameters relevant to smoking status and mortality. Mutations in ctDNA may serve as an early detection tool for cancer. This study quantitatively confirms the hypothesis that ctDNAs in circulation is the result of dissemination of aggressive tumor clones and survival of resistant clones. This study supports the use of ctDNA profiling as a less-invasive approach to monitor cancer progression and selection of appropriate drugs during cancer evolution.


Assuntos
DNA de Neoplasias/genética , Mutação , Invasividade Neoplásica/genética , Neoplasias/genética , Células Neoplásicas Circulantes , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos/uso terapêutico , Quimiorradioterapia , Células Clonais , Progressão da Doença , Receptores ErbB/antagonistas & inibidores , Cloridrato de Erlotinib/uso terapêutico , Feminino , Perfilação da Expressão Gênica , Genes Neoplásicos , Genes erbB-1 , Genes p53 , Genes ras , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/mortalidade , Neoplasias Pulmonares/terapia , Masculino , Pessoa de Meia-Idade , Proteínas de Neoplasias/genética , Neoplasias/mortalidade , Neoplasias/patologia , Células-Tronco Neoplásicas , Inibidores de Proteínas Quinases/uso terapêutico , Estudos Retrospectivos , Análise de Sequência de DNA , Fumar/genética
8.
Am J Physiol Lung Cell Mol Physiol ; 309(2): L129-38, 2015 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-26001777

RESUMO

Genetic data suggest that IL-6 trans-signaling may have a pathogenic role in the lung; however, the effects of IL-6 trans-signaling on lung effector cells have not been investigated. In this study, human airway smooth muscle (HASM) cells were treated with IL-6 (classical) or IL-6+sIL6R (trans-signaling) for 24 h and gene expression was measured by RNAseq. Intracellular signaling and transcription factor activation were assessed by Western blotting and luciferase assay, respectively. The functional effect of IL-6 trans-signaling was determined by proliferation assay. IL-6 trans-signaling had no effect on phosphoinositide-3 kinase and Erk MAP kinase pathways in HASM cells. Both classical and IL-6 trans-signaling in HASM involves activation of Stat3. However, the kinetics of Stat3 phosphorylation by IL-6 trans-signaling was different than classical IL-6 signaling. This was further reflected in the differential gene expression profile by IL-6 trans-signaling in HASM cells. Under IL-6 trans-signaling conditions 36 genes were upregulated, including PLA2G2A, IL13RA1, MUC1, and SOD2. Four genes, including CCL11, were downregulated at least twofold. The expression of 112 genes was divergent between IL-6 classical and trans-signaling, including the genes HILPDA, NNMT, DAB2, MUC1, WWC1, and VEGFA. Pathway analysis revealed that IL-6 trans-signaling induced expression of genes involved in regulation of airway remodeling, immune response, hypoxia, and glucose metabolism. Treatment of HASM cells with IL-6+sIL6R induced proliferation in a dose-dependent fashion, suggesting a role for IL-6 trans-signaling in asthma pathogenesis. These novel findings demonstrate differential effect of IL-6 trans-signaling on airway cells and identify IL-6 trans-signaling as a potential modifier of airway inflammation and remodeling.


Assuntos
Asma/metabolismo , Biomarcadores/metabolismo , Perfilação da Expressão Gênica , Interleucina-6/farmacologia , Músculo Liso/metabolismo , Sistema Respiratório/metabolismo , Traqueia/metabolismo , Asma/genética , Asma/patologia , Western Blotting , Proliferação de Células/efeitos dos fármacos , Humanos , Músculo Liso/citologia , Músculo Liso/efeitos dos fármacos , Análise de Sequência com Séries de Oligonucleotídeos , Fosforilação/efeitos dos fármacos , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Sistema Respiratório/citologia , Sistema Respiratório/efeitos dos fármacos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Traqueia/citologia , Traqueia/efeitos dos fármacos
9.
Neurol Res Int ; 2012: 170426, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22900172

RESUMO

A prominent clinical feature of ALS is muscle weakness due to dysfunction, denervation and degeneration of motoneurons (MNs). While MN degeneration is a late stage event in the ALS mouse model, muscle denervation occurs significantly earlier in the disease. Strategies to prevent this early denervation may improve quality of life by maintaining muscle control and slowing disease progression. The precise cause of MN dysfunction and denervation is not known, but several mechanisms have been proposed that involve potentially toxic intra- and extracellular changes. Many cells confront these changes by mounting a stress response that includes increased expression of heat shock protein 70 (Hsp70). MNs do not upregulate Hsp70, and this may result in a potentially increased vulnerability. We previously reported that recombinant human hsp70 (rhHsp70) injections delayed symptom onset and increased lifespan in SOD1(G93A) mice. The exogenous rhHsp70 was localized to the muscle and not to spinal cord or brain suggesting it modulates peripheral pathophysiology. In the current study, we focused on earlier administration of Hsp70 and its effect on initial muscle denervation. Injections of the protein appeared to arrest denervation with preserved large myelinated peripheral axons, and reduced glial activation.

10.
J Allergy Clin Immunol ; 130(2): 510-5.e1, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22554704

RESUMO

BACKGROUND: The IL6R single nucleotide polymorphism (SNP) rs4129267 has recently been identified as an asthma susceptibility locus in subjects of European ancestry but has not been characterized with respect to asthma severity. The SNP rs4129267 is in linkage disequilibrium (r(2) = 1) with the IL6R coding SNP rs2228145 (Asp(358)Ala). This IL6R coding change increases IL-6 receptor (IL-6R) shedding and promotes IL-6 transsignaling. OBJECTIVES: We sought to evaluate the IL6R SNP rs2228145 with respect to asthma severity phenotypes. METHODS: The IL6R SNP rs2228145 was evaluated in subjects of European ancestry with asthma from the Severe Asthma Research Program (SARP). Lung function associations were replicated in the Collaborative Study on the Genetics of Asthma (CSGA) cohort. Serum soluble IL-6R levels were measured in subjects from SARP. Immunohistochemistry was used to qualitatively evaluate IL-6R protein expression in bronchoalveolar lavage cells and endobronchial biopsies. RESULTS: The minor C allele of IL6R SNP rs2228145 was associated with a lower percent predicted FEV(1) in the SARP cohort (P= .005), the CSGA cohort (P= .008), and in a combined cohort analysis (P= .003). Additional associations with percent predicted forced vital capacity (FVC), FEV(1)/FVC ratio, and PC(20) were observed. The rs2228145 C allele (Ala(358)) was more frequent in severe asthma phenotypic clusters. Elevated serum soluble IL-6R levels were associated with lower percent predicted FEV(1) (P= .02) and lower percent predicted FVC (P= .008) (n= 146). IL-6R protein expression was observed in bronchoalveolar lavage macrophages, airway epithelium, vascular endothelium, and airway smooth muscle. CONCLUSIONS: The IL6R coding SNP rs2228145 (Asp(358)Ala) is a potential modifier of lung function in subjects with asthma and might identify subjects at risk for more severe asthma. IL-6 transsignaling might have a pathogenic role in the lung.


Assuntos
Asma/genética , Expressão Gênica/imunologia , Polimorfismo de Nucleotídeo Único/genética , Receptores de Interleucina-6/genética , População Branca/genética , Adolescente , Adulto , Asma/imunologia , Asma/fisiopatologia , Líquido da Lavagem Broncoalveolar/química , Criança , Estudos de Coortes , Feminino , Volume Expiratório Forçado/genética , Genótipo , Humanos , Interleucina-6/genética , Interleucina-6/metabolismo , Desequilíbrio de Ligação , Pulmão/imunologia , Pulmão/patologia , Pulmão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Fenótipo , Polimorfismo de Nucleotídeo Único/imunologia , Receptores de Interleucina-6/metabolismo , Índice de Gravidade de Doença , Transdução de Sinais/genética , Transdução de Sinais/imunologia , Capacidade Vital/genética
11.
Dev Neurobiol ; 72(5): 699-712, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21834083

RESUMO

Motoneurons (MN) as well as most neuronal populations undergo a temporally and spatially specific period of programmed cell death (PCD). Several factors have been considered to regulate the survival of MNs during this period, including availability of muscle-derived trophic support and activity. The possibility that target-derived factors may also negatively regulate MN survival has been considered, but not pursued. Neurotrophin precursors, through their interaction with p75(NTR) and sortilin receptors have been shown to induce cell death during development and following injury in the CNS. In this study, we find that muscle cells produce and secrete proBDNF. ProBDNF through its interaction with p75(NTR) and sortilin, promotes a caspase-dependent death of MNs in culture. We also provide data to suggest that proBDNF regulates MN PCD during development in vivo.


Assuntos
Apoptose/fisiologia , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Neurônios Motores/metabolismo , Músculo Esquelético/embriologia , Precursores de Proteínas/metabolismo , Medula Espinal/embriologia , Proteínas Adaptadoras de Transporte Vesicular/antagonistas & inibidores , Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Animais , Astrócitos/citologia , Fator Neurotrófico Derivado do Encéfalo/antagonistas & inibidores , Fator Neurotrófico Derivado do Encéfalo/biossíntese , Caspase 3/metabolismo , Caspase 7/metabolismo , Comunicação Celular/fisiologia , Embrião de Galinha , Galinhas , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Fibras Musculares Esqueléticas/citologia , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/inervação , Músculo Esquelético/metabolismo , Cultura Primária de Células , Precursores de Proteínas/antagonistas & inibidores , Receptor de Fator de Crescimento Neural/metabolismo , Medula Espinal/citologia
12.
Dev Neurobiol ; 68(1): 1-17, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17918243

RESUMO

Proper sensing of stress and the initiation of the stress response are critical to maintaining cell viability in response to noxious stimuli. Induction of the stress response prior to the exposure of a lethal stress (preconditioning) can be protective. Heat shock proteins (Hsps), the main products of the stress response, are considered to be responsible for this protective effect. Most cells readily initiate a stress response, but some neuronal phenotypes, including motoneurons (MNs), have a diminished capacity to do so. We have found that, given a proper stimulus, MNs can execute a heat stress response; but, it does not protect them from death caused by hydrogen peroxide (H(2)O(2)) induced oxidative stress, despite inhibiting H(2)O(2)-induced caspase activation. Conversely, we demonstrate that incubation with the heat shock cognate 70 (Hsc70) protein prior to oxidative insult can protect MNs from oxidative stress. This survival promoting effect may be mediated through the substrate binding domain (SBD) of Hsc70. Our data suggest that stress preconditioning may not be beneficial to MNs, but that pharmacological interventions and alternative means of acquiring components of the stress response are an effective means of ameliorating lethal stress in MNs and may be potentially useful therapeutically in preventing pathological MN loss.


Assuntos
Proteínas de Choque Térmico HSC70/farmacologia , Hipertermia Induzida , Neurônios Motores/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Animais , Cálcio/metabolismo , Caspases/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Embrião de Galinha , Relação Dose-Resposta a Droga , Interações Medicamentosas , Inibidores Enzimáticos/farmacologia , Proteínas de Choque Térmico HSC70/química , Peróxido de Hidrogênio/toxicidade , Oligopeptídeos/farmacologia , Estrutura Terciária de Proteína/fisiologia , Medula Espinal/citologia , Fatores de Tempo
13.
J Neurosci ; 27(48): 13173-80, 2007 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-18045911

RESUMO

Amyotrophic lateral sclerosis (ALS) is a debilitating neurodegenerative disorder that results in the progressive loss of motoneurons (MNs) in the CNS. Several survival and death mechanisms of MNs have been characterized and it has been determined that MNs do not appear to mount a complete stress response, as determined by the lack of heat shock protein 70 (Hsp70) upregulation after several stress paradigms. Hsp70 has been shown to confer neuroprotection and the insufficient availability of Hsp70 may contribute to MNs' susceptibility to death in ALS mice. In this study, recombinant human Hsp70 (rhHsp70) was intraperitoneally injected three times weekly, beginning at postnatal day 50 until endstage, to G93A mutant SOD1 (G93A SOD1) mice. The administration of rhHsp70 was effective at increasing lifespan, delaying symptom onset, preserving motor function and prolonging MN survival. Interestingly, injected rhHsp70 localized to skeletal muscle and was not readily detected in the CNS. Treatment with rhHsp70 also resulted in an increased number of innervated neuromuscular junctions compared with control tissue. Together these results suggest rhHsp70 may delay disease progression in the G93A SOD1 mouse via a yet to be identified peripheral mechanism.


Assuntos
Esclerose Lateral Amiotrófica/tratamento farmacológico , Esclerose Lateral Amiotrófica/mortalidade , Modelos Animais de Doenças , Proteínas de Choque Térmico HSP70/administração & dosagem , Fármacos Neuroprotetores/uso terapêutico , Fatores Etários , Esclerose Lateral Amiotrófica/patologia , Esclerose Lateral Amiotrófica/fisiopatologia , Análise de Variância , Animais , Comportamento Animal , Proteínas de Choque Térmico HSP70/metabolismo , Membro Posterior/patologia , Camundongos , Camundongos Transgênicos , Atividade Motora/efeitos dos fármacos , Neurônios Motores/efeitos dos fármacos , Junção Neuromuscular , Riluzol/uso terapêutico , Medula Espinal/efeitos dos fármacos , Medula Espinal/patologia , Superóxido Dismutase/genética
14.
Dev Neurobiol ; 67(13): 1815-29, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17701989

RESUMO

The ability to mount a successful stress response in the face of injury is critical to the long-term viability of individual cells and to the organism in general. The stress response, characterized in part by the upregulation of heat shock proteins, is compromised in several neurodegenerative disorders and in some neuronal populations, including motoneurons (MNs). Because astrocytes have a greater capacity than neurons to survive metabolic stress, and because they are intimately associated with the regulation of neuronal function, it is important to understand their stress response, so that we may to better appreciate the impact of stress on neuronal viability during injury or disease. We show that astrocytes subjected to hyperthermia upregulate Hsp/c70 in addition to intracellular signaling components including activated forms of extracellular-signal-regulated kinase (ERK1/2), Akt, and c-jun N-terminal kinase/stress activated protein kinase (JNK/SAPK). Furthermore, astrocytes release increasing amounts of Hsp/c70 into the extracellular environment following stress, an event that is abrogated when signaling through the ERK1/2 and phosphatidylinositol-3 kinase (PI3K) pathways is compromised and enhanced by inhibition of the JNK pathway. Last, we show that the Hsp/c70 is released from astrocytes in exosomes. Together, these data illustrate the diverse regulation of stress-induced Hsp/c70 release in exosomes, and the way in which the balance of activated signal transduction pathways affects this release. These data highlight how stressful insults can alter the microenvironment of an astrocyte, which may ultimately have implications for the survival of neighboring neurons.


Assuntos
Astrócitos/metabolismo , Proteínas de Choque Térmico HSP70/metabolismo , Fosfotransferases/metabolismo , Transdução de Sinais/fisiologia , Animais , Western Blotting , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Febre/fisiopatologia , Técnicas In Vitro , MAP Quinase Quinase 4/metabolismo , Estresse Oxidativo/fisiologia , Proteínas Proto-Oncogênicas c-akt/metabolismo
15.
Nat Protoc ; 2(6): 1499-507, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17545986

RESUMO

This protocol details methods to isolate and purify astrocytes and motoneurons (MNs) from the chick lumbar spinal cord. In addition, an approach to study the influences of astrocyte secreted factors on MNs is provided. Astrocytes are isolated between embryonic days 10 and 12 (E10-12), propagated in serum (2-3 h) and differentiated in chemically defined medium (3-4 h). When prepared according to this protocol, astrocyte cultures are more than 98% pure when assessed using the astrocyte-specific markers glial fibrillary acidic protein (GFAP) and S100beta. MNs are isolated between E5.5 and 6.0 (3-4 h) using a procedure that takes selective advantage of the large size of these cells. These cultures can be maintained using individual trophic factors, target-derived factors or astrocyte-derived factors, the preparation of which is also described (5-6 h). All or part of these techniques can be used to investigate a variety of processes that occur during nervous system development and disease or after injury.


Assuntos
Astrócitos/citologia , Técnicas de Cultura de Células/métodos , Neurônios Motores/citologia , Animais , Comunicação Celular , Embrião de Galinha , Medula Espinal/citologia
16.
J Neurosci ; 27(3): 634-44, 2007 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-17234595

RESUMO

During development, motoneurons (MNs) undergo a highly stereotyped, temporally and spatially defined period of programmed cell death (PCD), the result of which is the loss of 40-50% of the original neuronal population. Those MNs that survive are thought to reflect the successful acquisition of limiting amounts of trophic factors from the target. In contrast, maturation of MNs limits the need for target-derived trophic factors, because axotomy of these neurons in adulthood results in minimal neuronal loss. It is unclear whether MNs lose their need for trophic factors altogether or whether, instead, they come to rely on other cell types for nourishment. Astrocytes are known to supply trophic factors to a variety of neuronal populations and thus may nourish MNs in the absence of target-derived factors. We investigated the survival-promoting activities of muscle- and astrocyte-derived secreted factors and found that astrocyte-conditioned media (ACM) was able to save substantially more motoneurons in vitro than muscle-conditioned media (MCM). Our results indicate that both ACM and MCM are significant sources of MN trophic support in vitro and in ovo, but only ACM can rescue MNs after unilateral limb bud removal. Furthermore, we provide evidence suggesting that MCM facilitates the death of a subpopulation of MNs in a p75(NTR) - and caspase-dependent manner; however, maturation in ACM results in MN trophic independence and reduced vulnerability to this negative, pro-apoptotic influence from the target.


Assuntos
Astrócitos/metabolismo , Neurônios Motores/fisiologia , Músculo Esquelético/metabolismo , Animais , Astrócitos/citologia , Sobrevivência Celular/fisiologia , Células Cultivadas , Embrião de Galinha , Meios de Cultivo Condicionados/farmacocinética , Neurônios Motores/citologia , Músculo Esquelético/citologia
17.
J Neurosci ; 25(42): 9735-45, 2005 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-16237177

RESUMO

The dependence of developing spinal motoneuron survival on a soluble factor(s) from their target, muscle tissue is well established both in vivo and in vitro. Considering this apparent dependence, we examined whether a specific component of the stress response mediates motoneuron survival in trophic factor-deprived environments. We demonstrate that, although endogenous expression of heat shock protein 70 (HSP70) did not change during trophic factor deprivation, application of e-rhHsp70 (exogenous recombinant human Hsp70) promoted motoneuron survival. Conversely, depletion of HSP70 from chick muscle extract (MEx) potently reduces the survival-promoting activity of MEx. Additionally, exogenous treatment with or spinal cord overexpression of Hsp70 enhances motoneuron survival in vivo during the period of naturally occurring cell death [programmed cell death (PCD)]. Hindlimb muscle cells and lumbar spinal astrocytes readily secrete HSP70 in vitro, suggesting potential physiological sources of extracellular Hsp70 for motoneurons. However, in contrast to exogenous treatment with or overexpression of Hsp70 in vivo, muscle-targeted injections of this factor in an ex vivo preparation fail to attenuate motoneuron PCD. These data (1) suggest that motoneuron survival requirements may extend beyond classical trophic factors to include HSP70, (2) indicate that the source of this factor is instrumental in determining its trophic function, and (3) may therefore influence therapeutic strategies designed to increase motoneuron Hsp70 signaling during disease or injury.


Assuntos
Sobrevivência Celular/fisiologia , Líquido Extracelular/citologia , Líquido Extracelular/fisiologia , Proteínas de Choque Térmico HSP70/fisiologia , Neurônios Motores/citologia , Neurônios Motores/fisiologia , Animais , Morte Celular/fisiologia , Células Cultivadas , Embrião de Galinha
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