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1.
Ther Adv Med Oncol ; 14: 17588359221122729, 2022.
Article in English | MEDLINE | ID: mdl-36312814

ABSTRACT

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.
Article in English | MEDLINE | ID: mdl-31611269

ABSTRACT

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.


Subject(s)
Amyotrophic Lateral Sclerosis/genetics , Amyotrophic Lateral Sclerosis/metabolism , Amyotrophic Lateral Sclerosis/physiopathology , Disease Progression , Interleukin-6/metabolism , Receptors, Interleukin-6/genetics , Receptors, Interleukin-6/metabolism , Adult , Aged , Case-Control Studies , Cohort Studies , Female , Humans , Male , Middle Aged
3.
Radiat Res ; 192(2): 145-158, 2019 08.
Article in English | MEDLINE | ID: mdl-31166846

ABSTRACT

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.


Subject(s)
Beta Particles/adverse effects , Skin/injuries , Skin/radiation effects , Animals , Cell Proliferation/radiation effects , Dose-Response Relationship, Radiation , Female , Skin/metabolism , Skin/pathology , Swine , Transcriptome/radiation effects
4.
Biomed Phys Eng Express ; 6(1): 015007, 2019 11 25.
Article in English | MEDLINE | ID: mdl-33438595

ABSTRACT

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.


Subject(s)
Beta Particles/adverse effects , Radiation Injuries, Experimental/pathology , Skin/pathology , Skin/radiation effects , Algorithms , Animals , Automation , Feasibility Studies , Female , Necrosis , Pathologists , Swine
5.
Leuk Lymphoma ; 59(8): 1871-1877, 2018 08.
Article in English | MEDLINE | ID: mdl-29252084

ABSTRACT

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.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Hyperglycemia/diagnosis , Lymphoma, Non-Hodgkin/drug therapy , Aged , Antibodies, Monoclonal, Murine-Derived/administration & dosage , Antibodies, Monoclonal, Murine-Derived/adverse effects , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Blood Glucose/analysis , Cyclophosphamide/administration & dosage , Cyclophosphamide/adverse effects , Doxorubicin/administration & dosage , Doxorubicin/adverse effects , Etoposide/administration & dosage , Etoposide/adverse effects , Female , Humans , Hyperglycemia/blood , Hyperglycemia/chemically induced , Kaplan-Meier Estimate , Lymphoma, Non-Hodgkin/blood , Male , Middle Aged , Prednisone/administration & dosage , Prednisone/adverse effects , Retrospective Studies , Rituximab/administration & dosage , Rituximab/adverse effects , Vincristine/administration & dosage , Vincristine/adverse effects
6.
Theranostics ; 7(11): 2914-2923, 2017.
Article in English | MEDLINE | ID: mdl-28824725

ABSTRACT

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.


Subject(s)
Colorectal Neoplasms/pathology , Lung Neoplasms/pathology , Mutation , Tobacco Smoking/adverse effects , Urinary Bladder Neoplasms/pathology , Black or African American , Humans , Pathology, Molecular , Sequence Analysis, DNA , Tumor Suppressor Protein p53/genetics , White People
7.
J Hematol Oncol ; 10(1): 100, 2017 05 04.
Article in English | MEDLINE | ID: mdl-28472989

ABSTRACT

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.


Subject(s)
DNA, Neoplasm/genetics , Mutation , Neoplasm Invasiveness/genetics , Neoplasms/genetics , Neoplastic Cells, Circulating , Adult , Aged , Aged, 80 and over , Antineoplastic Agents/therapeutic use , Chemoradiotherapy , Clone Cells , Disease Progression , ErbB Receptors/antagonists & inhibitors , Erlotinib Hydrochloride/therapeutic use , Female , Gene Expression Profiling , Genes, Neoplasm , Genes, erbB-1 , Genes, p53 , Genes, ras , Humans , Lung Neoplasms/genetics , Lung Neoplasms/mortality , Lung Neoplasms/therapy , Male , Middle Aged , Neoplasm Proteins/genetics , Neoplasms/mortality , Neoplasms/pathology , Neoplastic Stem Cells , Protein Kinase Inhibitors/therapeutic use , Retrospective Studies , Sequence Analysis, DNA , Smoking/genetics
8.
Am J Physiol Lung Cell Mol Physiol ; 309(2): L129-38, 2015 Jul 15.
Article in English | MEDLINE | ID: mdl-26001777

ABSTRACT

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.


Subject(s)
Asthma/metabolism , Biomarkers/metabolism , Gene Expression Profiling , Interleukin-6/pharmacology , Muscle, Smooth/metabolism , Respiratory System/metabolism , Trachea/metabolism , Asthma/genetics , Asthma/pathology , Blotting, Western , Cell Proliferation/drug effects , Humans , Muscle, Smooth/cytology , Muscle, Smooth/drug effects , Oligonucleotide Array Sequence Analysis , Phosphorylation/drug effects , RNA, Messenger/genetics , Real-Time Polymerase Chain Reaction , Respiratory System/cytology , Respiratory System/drug effects , Reverse Transcriptase Polymerase Chain Reaction , Signal Transduction , Trachea/cytology , Trachea/drug effects
9.
Neurol Res Int ; 2012: 170426, 2012.
Article in English | MEDLINE | ID: mdl-22900172

ABSTRACT

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.
Article in English | MEDLINE | ID: mdl-22554704

ABSTRACT

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.


Subject(s)
Asthma/genetics , Gene Expression/immunology , Polymorphism, Single Nucleotide/genetics , Receptors, Interleukin-6/genetics , White People/genetics , Adolescent , Adult , Asthma/immunology , Asthma/physiopathology , Bronchoalveolar Lavage Fluid/chemistry , Child , Cohort Studies , Female , Forced Expiratory Volume/genetics , Genotype , Humans , Interleukin-6/genetics , Interleukin-6/metabolism , Linkage Disequilibrium , Lung/immunology , Lung/pathology , Lung/physiopathology , Male , Middle Aged , Phenotype , Polymorphism, Single Nucleotide/immunology , Receptors, Interleukin-6/metabolism , Severity of Illness Index , Signal Transduction/genetics , Signal Transduction/immunology , Vital Capacity/genetics
11.
Dev Neurobiol ; 72(5): 699-712, 2012 May.
Article in English | MEDLINE | ID: mdl-21834083

ABSTRACT

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.


Subject(s)
Apoptosis/physiology , Brain-Derived Neurotrophic Factor/metabolism , Motor Neurons/metabolism , Muscle, Skeletal/embryology , Protein Precursors/metabolism , Spinal Cord/embryology , Adaptor Proteins, Vesicular Transport/antagonists & inhibitors , Adaptor Proteins, Vesicular Transport/metabolism , Animals , Astrocytes/cytology , Brain-Derived Neurotrophic Factor/antagonists & inhibitors , Brain-Derived Neurotrophic Factor/biosynthesis , Caspase 3/metabolism , Caspase 7/metabolism , Cell Communication/physiology , Chick Embryo , Chickens , Gene Expression Regulation, Developmental/physiology , Muscle Fibers, Skeletal/cytology , Muscle Fibers, Skeletal/metabolism , Muscle, Skeletal/innervation , Muscle, Skeletal/metabolism , Primary Cell Culture , Protein Precursors/antagonists & inhibitors , Receptor, Nerve Growth Factor/metabolism , Spinal Cord/cytology
12.
Dev Neurobiol ; 68(1): 1-17, 2008 Jan.
Article in English | MEDLINE | ID: mdl-17918243

ABSTRACT

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.


Subject(s)
HSC70 Heat-Shock Proteins/pharmacology , Hyperthermia, Induced , Motor Neurons/drug effects , Oxidative Stress/drug effects , Animals , Calcium/metabolism , Caspases/metabolism , Cell Survival/drug effects , Cells, Cultured , Chick Embryo , Dose-Response Relationship, Drug , Drug Interactions , Enzyme Inhibitors/pharmacology , HSC70 Heat-Shock Proteins/chemistry , Hydrogen Peroxide/toxicity , Oligopeptides/pharmacology , Protein Structure, Tertiary/physiology , Spinal Cord/cytology , Time Factors
13.
J Neurosci ; 27(48): 13173-80, 2007 Nov 28.
Article in English | MEDLINE | ID: mdl-18045911

ABSTRACT

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.


Subject(s)
Amyotrophic Lateral Sclerosis/drug therapy , Amyotrophic Lateral Sclerosis/mortality , Disease Models, Animal , HSP70 Heat-Shock Proteins/administration & dosage , Neuroprotective Agents/therapeutic use , Age Factors , Amyotrophic Lateral Sclerosis/pathology , Amyotrophic Lateral Sclerosis/physiopathology , Analysis of Variance , Animals , Behavior, Animal , HSP70 Heat-Shock Proteins/metabolism , Hindlimb/pathology , Mice , Mice, Transgenic , Motor Activity/drug effects , Motor Neurons/drug effects , Neuromuscular Junction , Riluzole/therapeutic use , Spinal Cord/drug effects , Spinal Cord/pathology , Superoxide Dismutase/genetics
14.
Dev Neurobiol ; 67(13): 1815-29, 2007 Nov.
Article in English | MEDLINE | ID: mdl-17701989

ABSTRACT

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.


Subject(s)
Astrocytes/metabolism , HSP70 Heat-Shock Proteins/metabolism , Phosphotransferases/metabolism , Signal Transduction/physiology , Animals , Blotting, Western , Extracellular Signal-Regulated MAP Kinases/metabolism , Fever/physiopathology , In Vitro Techniques , MAP Kinase Kinase 4/metabolism , Oxidative Stress/physiology , Proto-Oncogene Proteins c-akt/metabolism
15.
Nat Protoc ; 2(6): 1499-507, 2007.
Article in English | MEDLINE | ID: mdl-17545986

ABSTRACT

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.


Subject(s)
Astrocytes/cytology , Cell Culture Techniques/methods , Motor Neurons/cytology , Animals , Cell Communication , Chick Embryo , Spinal Cord/cytology
16.
J Neurosci ; 27(3): 634-44, 2007 Jan 17.
Article in English | MEDLINE | ID: mdl-17234595

ABSTRACT

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.


Subject(s)
Astrocytes/metabolism , Motor Neurons/physiology , Muscle, Skeletal/metabolism , Animals , Astrocytes/cytology , Cell Survival/physiology , Cells, Cultured , Chick Embryo , Culture Media, Conditioned/pharmacokinetics , Motor Neurons/cytology , Muscle, Skeletal/cytology
17.
J Neurosci ; 25(42): 9735-45, 2005 Oct 19.
Article in English | MEDLINE | ID: mdl-16237177

ABSTRACT

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.


Subject(s)
Cell Survival/physiology , Extracellular Fluid/cytology , Extracellular Fluid/physiology , HSP70 Heat-Shock Proteins/physiology , Motor Neurons/cytology , Motor Neurons/physiology , Animals , Cell Death/physiology , Cells, Cultured , Chick Embryo
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