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1.
Am Surg ; 90(6): 1250-1254, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38217436

ABSTRACT

BACKGROUND: The Rural Trauma Team Development Course (RTTDC) is designed to help rural hospitals better organize and manage trauma patients with limited resources. Although RTTDC is well-established, limited literature exists regarding improvement in the overall objectives for which the course was designed. The aim of this study was to analyze the goals of RTTDC, hypothesizing improvements in course objectives after course completion. METHODS: This was a prospective, observational study from 2015 through 2021. All hospitals completing the RTTDC led by our Level 1, academic trauma hospital were included. Our institutional database was queried for individual patient data. Cohorts were delineated before and after RTTDC was provided to the rural hospital. Basic demographics were obtained. Outcomes of interest included: Emergency Department (ED) dwell time, decision time to transfer, number of total images/computed tomography scans obtained, and mortality. Chi square and non-parametric median test were used. Significance was set at P < .05. RESULTS: Sixteen rural hospitals were included with a total of 472 patients transferred (240 before and 232 after). Patient demographics were similar before and after RTTDC. ED dwell time was significantly reduced by 64 min (P = .003) and decision to transfer time was cut by 62 min (P = .004) after RTTDC. Mean total radiographic images and CT scans were significantly reduced (P < .001 and P = .002, respectively) after RTTDC. Mortality was unaffected by RTTDC completion (P = .941). CONCLUSION: The RTTDC demonstrates decreased ED dwell time, decision time to transfer, and number of radiographic images obtained prior to transfer. More rural hospitals should be offered this course.


Subject(s)
Hospitals, Rural , Patient Care Team , Trauma Centers , Humans , Prospective Studies , Patient Care Team/organization & administration , Male , Female , Middle Aged , Adult , Emergency Service, Hospital , Wounds and Injuries/therapy , Wounds and Injuries/mortality , Patient Transfer/statistics & numerical data , Organizational Objectives
2.
Stem Cells Transl Med ; 13(3): 219-229, 2024 Mar 15.
Article in English | MEDLINE | ID: mdl-38097199

ABSTRACT

Bone marrow (BM)-derived mesenchymal stromal cells (MSCs) are promising candidates for cell-based therapy for several immune-mediated inflammatory diseases (IMIDs) due to their multiplicity of immunomodulatory and reparative properties and favorable safety profile. However, although preclinical data were encouraging, the clinical benefit demonstrated in clinical trials of autologous MSC transplantation in a number of conditions has been less robust. This may be explained by the growing body of evidence pointing to abnormalities of the bone marrow microenvironment in IMIDs, including impaired MSC function. However, it is not currently known whether these abnormalities arise as a cause or consequence of disease, the role they play in disease initiation and/or progression, or whether they themselves are targets for disease modification. Here, we review current knowledge about the function of the BM microenvironment in IMIDs including multiple sclerosis, systemic lupus erythematosus, rheumatoid arthritis, and type I diabetes, focusing on MSCs in particular. We predict that an improved understanding of disease-related changes in the bone marrow microenvironment including the role of MSCs in vivo, will yield new insights into pathophysiology and aid identification of new drug targets and optimization of cell-based therapy in IMIDs.


Subject(s)
Mesenchymal Stem Cell Transplantation , Mesenchymal Stem Cells , Bone Marrow , Bone Marrow Cells , Immunomodulating Agents , Mesenchymal Stem Cells/physiology , Transplantation, Autologous , Humans
4.
Nat Commun ; 13(1): 4655, 2022 08 09.
Article in English | MEDLINE | ID: mdl-35945193

ABSTRACT

Friedreich's ataxia (FA) is an inherited progressive neurodegenerative disease for which there is no proven disease-modifying treatment. Here we perform an open-label, pilot study of recombinant human granulocyte-colony stimulating factor (G-CSF) administration in seven people with FA (EudraCT: 2017-003084-34); each participant receiving a single course of G-CSF (Lenograstim; 1.28 million units per kg per day for 5 days). The primary outcome is peripheral blood mononuclear cell frataxin levels over a 19-day period. The secondary outcomes include safety, haematopoietic stem cell (HSC) mobilisation, antioxidant levels and mitochondrial enzyme activity. The trial meets pre-specified endpoints. We show that administration of G-CSF to people with FA is safe. Mobilisation of HSCs in response to G-CSF is comparable to that of healthy individuals. Notably, sustained increases in cellular frataxin concentrations and raised PGC-1α and Nrf2 expression are detected. Our findings show potential for G-CSF therapy to have a clinical impact in people with FA.


Subject(s)
Friedreich Ataxia , Granulocyte Colony-Stimulating Factor , Recombinant Proteins , Friedreich Ataxia/drug therapy , Granulocyte Colony-Stimulating Factor/adverse effects , Granulocytes/metabolism , Humans , Leukocytes, Mononuclear/metabolism , Pilot Projects , Recombinant Proteins/adverse effects
5.
Mult Scler ; 28(8): 1179-1188, 2022 07.
Article in English | MEDLINE | ID: mdl-34841955

ABSTRACT

BACKGROUND: Cell-based therapies for multiple sclerosis (MS), including those employing autologous bone marrow-derived mesenchymal stromal cells (MSC) are being examined in clinical trials. However, recent studies have identified abnormalities in the MS bone marrow microenvironment. OBJECTIVE: We aimed to compare the secretome of MSC isolated from control subjects (C-MSC) and people with MS (MS-MSC) and explore the functional relevance of findings. METHODS: We employed high throughput proteomic analysis, enzyme-linked immunosorbent assays and immunoblotting, as well as in vitro assays of enzyme activity and neuroprotection. RESULTS: We demonstrated that, in progressive MS, the MSC secretome has lower levels of mitochondrial fumarate hydratase (mFH). Exogenous mFH restores the in vitro neuroprotective potential of MS-MSC. Furthermore, MS-MSC expresses reduced levels of fumarate hydratase (FH) with downstream reduction in expression of master regulators of oxidative stress. CONCLUSIONS: Our findings are further evidence of dysregulation of the bone marrow microenvironment in progressive MS with respect to anti-oxidative capacity and immunoregulatory potential. Given the clinical utility of the fumaric acid ester dimethyl fumarate in relapsing-remitting MS, our findings have potential implication for understanding MS pathophysiology and personalised therapeutic intervention.


Subject(s)
Fumarate Hydratase , Mesenchymal Stem Cells , Mitochondria , Multiple Sclerosis, Chronic Progressive , Neuroprotection , Fumarate Hydratase/metabolism , Humans , Mitochondria/enzymology , Multiple Sclerosis, Chronic Progressive/metabolism , Proteomics
6.
Surg Clin North Am ; 102(1): 169-180, 2022 Feb.
Article in English | MEDLINE | ID: mdl-34800385

ABSTRACT

Mass casualty incidents are increasingly common. They are defined by large numbers of patients arriving nearly simultaneously, overwhelming available resources needed for optimal care. They require rapid mobilization of resources to provide optimal outcomes and limit disability and death. Because the mechanism of injury in a mass casualty incident is often traumatic in nature, surgeons should be aware of the critical role they play in planning and response. The coronavirus disease 2019 pandemic is a notable, resulting in a sustained surge of critically ill patients. Initial response requires local mobilization of resources; large-scale events potentially require a national response.


Subject(s)
Civil Defense , Emergency Medical Services , Health Resources , Mass Casualty Incidents , COVID-19/epidemiology , COVID-19/prevention & control , Decision Trees , Humans , Triage
7.
Brain Pathol ; 30(6): 1041-1055, 2020 11.
Article in English | MEDLINE | ID: mdl-32580238

ABSTRACT

SAFB1 is a DNA and RNA binding protein that is highly expressed in the cerebellum and hippocampus and is involved in the processing of coding and non-coding RNAs, splicing and dendritic function. We analyzed SAFB1 expression in the post-mortem brain tissue of spinocerebellar ataxia (SCA), Huntington's disease (HD), Multiple sclerosis (MS), Parkinson's disease patients and controls. In SCA cases, the expression of SAFB1 in the nucleus was increased and there was abnormal and extensive expression in the cytoplasm where it co-localized with the markers of Purkinje cell injury. Significantly, no SAFB1 expression was found in the cerebellar neurons of the dentate nucleus in control or MS patients; however, in SCA patients, SAFB1 expression was increased significantly in both the nucleus and cytoplasm of dentate neurons. In HD, we found that SAFB1 expression was increased in the nucleus and cytoplasm of striatal neurons; however, there was no SAFB1 staining in the striatal neurons of controls. In PD substantia nigra, we did not see any changes in neuronal SAFB1 expression. iCLIP analysis found that SAFB1 crosslink sites within ATXN1 RNA were adjacent to the start and within the glutamine repeat sequence. Further investigation found increased binding of SAFB1 to pathogenic ATXN1-85Q mRNA. These novel data strongly suggest SAFB1 contributes to the etiology of SCA and Huntington's chorea and that it may be a pathological marker of polyglutamine repeat expansion diseases.


Subject(s)
Brain/metabolism , Huntington Disease/metabolism , Matrix Attachment Region Binding Proteins/metabolism , Neurons/metabolism , Nuclear Matrix-Associated Proteins/metabolism , Receptors, Estrogen/metabolism , Spinocerebellar Ataxias/metabolism , Aged , Aged, 80 and over , Brain/pathology , Cerebellum/metabolism , Cerebellum/pathology , Corpus Striatum/metabolism , Corpus Striatum/pathology , Female , Humans , Huntington Disease/pathology , Male , Middle Aged , Multiple Sclerosis/metabolism , Multiple Sclerosis/pathology , Neurons/pathology , Parkinson Disease/metabolism , Parkinson Disease/pathology , Purkinje Cells/metabolism , Purkinje Cells/pathology , Spinocerebellar Ataxias/pathology
8.
J Pathol ; 247(4): 422-434, 2019 04.
Article in English | MEDLINE | ID: mdl-30565681

ABSTRACT

The overall survival for patients with primary glioblastoma is very poor. Glioblastoma contains a subpopulation of glioma stem cells (GSC) that are responsible for tumour initiation, treatment resistance and recurrence. PPARα is a transcription factor involved in the control of lipid, carbohydrate and amino acid metabolism. We have recently shown that PPARα gene and protein expression is increased in glioblastoma and has independent clinical prognostic significance in multivariate analyses. In this work, we report that PPARα is overexpressed in GSC compared to foetal neural stem cells. To investigate the role of PPARα in GSC, we knocked down its expression using lentiviral transduction with short hairpin RNA (shRNA). Transduced GSC were tagged with luciferase and stereotactically xenografted into the striatum of NOD-SCID mice. Bioluminescent and magnetic resonance imaging showed that knockdown (KD) of PPARα reduced the tumourigenicity of GSC in vivo. PPARα-expressing control GSC xenografts formed invasive histological phenocopies of human glioblastoma, whereas PPARα KD GSC xenografts failed to establish viable intracranial tumours. PPARα KD GSC showed significantly reduced proliferative capacity and clonogenic potential in vitro with an increase in cellular senescence. In addition, PPARα KD resulted in significant downregulation of the stem cell factors c-Myc, nestin and SOX2. This was accompanied by downregulation of the PPARα-target genes and key regulators of fatty acid oxygenation ACOX1 and CPT1A, with no compensatory increase in glycolytic flux. These data establish the aberrant overexpression of PPARα in GSC and demonstrate that this expression functions as an important regulator of tumourigenesis, linking self-renewal and the malignant phenotype in this aggressive cancer stem cell subpopulation. We conclude that targeting GSC PPARα expression may be a therapeutically beneficial strategy with translational potential as an adjuvant treatment. © 2018 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.


Subject(s)
Brain Neoplasms/pathology , Glioblastoma/pathology , PPAR alpha/metabolism , RNA, Small Interfering/pharmacology , Animals , Biomarkers, Tumor/metabolism , Cell Transformation, Neoplastic , Down-Regulation , Female , Gene Expression Regulation, Neoplastic/physiology , Gene Knockdown Techniques/methods , Humans , Lentivirus , Mice, Inbred NOD , Mice, SCID , Neoplastic Stem Cells/pathology , Phenotype , Signal Transduction/physiology , Transplantation, Heterologous , Tumor Cells, Cultured
9.
Antioxid Redox Signal ; 30(17): 1983-1998, 2019 06 10.
Article in English | MEDLINE | ID: mdl-29808718

ABSTRACT

Aims: Epidemiologic evidence indicates that diabetes may increase risk of breast cancer (BC) and mortality in patients with cancer. The pathophysiological relationships between diabetes and cancer are not fully understood, and personalized treatments for diabetes-associated BC are urgently needed. Results: We observed that high glucose (HG), via activation of nuclear phosphatase PP2Cδ, suppresses p53 function, and consequently promotes BC cell proliferation, migration, and invasion. PP2Cδ expression is higher in tumor tissues from BC patients with hyperglycemia than those with normoglycemia. The mechanisms underlying HG stimulation of PP2Cδ involve classical/novel protein kinase-C (PKC) activation and GSK3ß phosphorylation. Reactive oxygen species (ROS)/NF-κB pathway also mediates HG induction of PP2Cδ. Furthermore, we identified a 1,5-diheteroarylpenta-1,4-dien-3-one (Compound 23, or C23) as a novel potent PP2Cδ inhibitor with a striking cytotoxicity on MCF-7 cells through cell-based screening assay for growth inhibition and activity of a group of curcumin mimics. Beside directly inhibiting PP2Cδ activity, C23 blocks HG induction of PP2Cδ expression via heat shock protein 27 (HSP27) induction and subsequent ablation of ROS/NF-κB activation. C23 can thus significantly block HG-triggered inhibition of p53 activity, leading to the inhibition of cancer cell proliferation, migration, and invasion. In addition, hyperglycemia promotes BC development in diabetic nude mice, and C23 inhibits the xenografted BC tumor growth. Conclusions and Innovation: Our findings elucidate mechanisms that may have contributed to diabetes-associated BC progression, and provide the first evidence to support the possible alternative therapeutic approach to BC patients with diabetes. Antioxid. Redox Signal. 30, 1983-1998.


Subject(s)
Antineoplastic Agents/pharmacology , Breast Neoplasms/metabolism , Breast Neoplasms/pathology , Curcumin/pharmacology , Enzyme Inhibitors/pharmacology , Glucose/metabolism , Protein Phosphatase 2C/antagonists & inhibitors , Acetylation , Animals , Antineoplastic Agents/chemistry , Breast Neoplasms/drug therapy , Cell Line, Tumor , Curcumin/analogs & derivatives , Curcumin/chemistry , Disease Models, Animal , Disease Progression , Enzyme Inhibitors/chemistry , Female , Glycogen Synthase Kinase 3 beta/metabolism , Humans , Hyperglycemia , Mice , Models, Molecular , NF-kappa B/metabolism , Phosphorylation , Protein Phosphatase 2C/chemistry , Reactive Oxygen Species/metabolism , Tumor Suppressor Protein p53/metabolism , Xenograft Model Antitumor Assays
10.
Stem Cells Transl Med ; 7(10): 748-758, 2018 10.
Article in English | MEDLINE | ID: mdl-30063300

ABSTRACT

The potential of autologous cell-based therapies including those using multipotent mesenchymal stromal cells (MSCs) is being investigated for multiple sclerosis (MS) and other neurological conditions. However, the phenotype of MSC in neurological diseases has not been fully characterized. We have previously shown that MSC isolated from patients with progressive MS (MS-MSC) have reduced expansion potential, premature senescence, and reduced neuroprotective potential in vitro. In view of the role of antioxidants in ageing and neuroprotection, we examined the antioxidant capacity of MS-MSC demonstrating that MS-MSC secretion of antioxidants superoxide dismutase 1 (SOD1) and glutathione S-transferase P (GSTP) is reduced and correlates negatively with the duration of progressive phase of MS. We confirmed reduced expression of SOD1 and GSTP by MS-MSC along with reduced activity of SOD and GST and, to examine the antioxidant capacity of MS-MSC under conditions of nitrosative stress, we established an in vitro cell survival assay using nitric oxide-induced cell death. MS-MSC displayed differential susceptibility to nitrosative stress with accelerated senescence and greater decline in expression of SOD1 and GSTP in keeping with reduced expression of master regulators of antioxidant responses nuclear factor erythroid 2-related factor 2 and peroxisome proliferator-activated receptor gamma coactivator 1-α. Our results are compatible with dysregulation of antioxidant responses in MS-MSC and have significant implications for development of autologous MSC-based therapies for MS, optimization of which may require that these functional deficits are reversed. Furthermore, improved understanding of the underlying mechanisms may yield novel insights into MS pathophysiology and biomarker identification. Stem Cells Translational Medicine 2018;7:748-758.


Subject(s)
Antioxidants/metabolism , Mesenchymal Stem Cells/metabolism , Multiple Sclerosis/pathology , Bone Marrow Cells/cytology , Cellular Senescence/drug effects , Female , Glutathione Transferase/genetics , Glutathione Transferase/metabolism , Humans , Male , Mesenchymal Stem Cell Transplantation , Mesenchymal Stem Cells/cytology , Middle Aged , Multiple Sclerosis/therapy , NF-E2-Related Factor 2/metabolism , Nitroso Compounds/pharmacology , Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha/genetics , Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha/metabolism , Superoxide Dismutase-1/genetics , Superoxide Dismutase-1/metabolism
11.
Acta Neuropathol ; 135(6): 907-921, 2018 06.
Article in English | MEDLINE | ID: mdl-29541917

ABSTRACT

Bone marrow-derived cells are known to infiltrate the adult brain and fuse with cerebellar Purkinje cells. Histological observations that such heterotypic cell fusion events are substantially more frequent following cerebellar injury suggest they could have a role in the protection of mature brain neurons. To date, the possibility that cell fusion can preserve or restore the structure and function of adult brain neurons has not been directly addressed; indeed, though frequently suggested, the possibility of benefit has always been rather speculative. Here we report, for the first time, that fusion of a bone marrow-derived cell with a neuron in vivo, in the mature brain, results in the formation of a spontaneously firing neuron. Notably, we also provide evidence supporting the concept that heterotypic cell fusion acts as a biological mechanism to repair pathological changes in Purkinje cell structure and electrophysiology. We induced chronic central nervous system inflammation in chimeric mice expressing bone marrow cells tagged with enhanced green fluorescent protein. Subsequent in-depth histological analysis revealed significant Purkinje cell injury. In addition, there was an increased incidence of cell fusion between bone marrow-derived cells and Purkinje cells, revealed as enhanced green fluorescent protein-expressing binucleate heterokaryons. These fused cells resembled healthy Purkinje cells in their morphology, soma size, ability to synthesize the neurotransmitter gamma-aminobutyric acid, and synaptic innervation from neighbouring cells. Extracellular recording of spontaneous firing ex vivo revealed a shift in the predominant mode of firing of non-fused Purkinje cells in the context of cerebellar inflammation. By contrast, the firing patterns of fused Purkinje cells were the same as in healthy control cerebellum, indicating that fusion of bone marrow-derived cells with Purkinje cells mitigated the effects of cell injury on electrical activity. Together, our histological and electrophysiological results provide novel fundamental insights into physiological processes by which nerve cells are protected in adult life.


Subject(s)
Bone Marrow Cells/physiology , Bone Marrow Transplantation , Encephalomyelitis, Autoimmune, Experimental/physiopathology , Encephalomyelitis, Autoimmune, Experimental/therapy , Purkinje Cells/physiology , Action Potentials/physiology , Animals , Bone Marrow Cells/pathology , Cell Fusion , Chimera , Encephalomyelitis, Autoimmune, Experimental/pathology , Female , Green Fluorescent Proteins/genetics , Green Fluorescent Proteins/metabolism , Inflammation/pathology , Inflammation/physiopathology , Mice, Inbred C57BL , Mice, Transgenic , Myelin Sheath/pathology , Myelin Sheath/physiology , Neuroprotection/physiology , Purkinje Cells/pathology , Tissue Culture Techniques
12.
Ann Neurol ; 83(4): 779-793, 2018 04.
Article in English | MEDLINE | ID: mdl-29534309

ABSTRACT

OBJECTIVE: Friedreich's ataxia is an incurable inherited neurological disease caused by frataxin deficiency. Here, we report the neuroreparative effects of myeloablative allogeneic bone marrow transplantation in a humanized murine model of the disease. METHODS: Mice received a transplant of fluorescently tagged sex-mismatched bone marrow cells expressing wild-type frataxin and were assessed at monthly intervals using a range of behavioral motor performance tests. At 6 months post-transplant, mice were euthanized for protein and histological analysis. In an attempt to augment numbers of bone marrow-derived cells integrating within the nervous system and improve therapeutic efficacy, a subgroup of transplanted mice also received monthly subcutaneous infusions of the cytokines granulocyte-colony stimulating factor and stem cell factor. RESULTS: Transplantation caused improvements in several indicators of motor coordination and locomotor activity. Elevations in frataxin levels and antioxidant defenses were detected. Abrogation of disease pathology throughout the nervous system was apparent, together with extensive integration of bone marrow-derived cells in areas of nervous tissue injury that contributed genetic material to mature neurons, satellite-like cells, and myelinating Schwann cells by processes including cell fusion. Elevations in circulating bone marrow-derived cell numbers were detected after cytokine administration and were associated with increased frequencies of Purkinje cell fusion and bone marrow-derived dorsal root ganglion satellite-like cells. Further improvements in motor coordination and activity were evident. INTERPRETATION: Our data provide proof of concept of gene replacement therapy, via allogeneic bone marrow transplantation, that reverses neurological features of Friedreich's ataxia with the potential for rapid clinical translation. Ann Neurol 2018;83:779-793.


Subject(s)
Bone Marrow Transplantation/methods , Friedreich Ataxia/surgery , Animals , Body Weight/physiology , Cytokines/metabolism , Disease Models, Animal , Exploratory Behavior/physiology , Friedreich Ataxia/genetics , Ganglia, Spinal/pathology , Granulocyte Colony-Stimulating Factor/metabolism , Granulocyte Colony-Stimulating Factor/therapeutic use , Green Fluorescent Proteins/genetics , Green Fluorescent Proteins/metabolism , Iron-Binding Proteins/genetics , Leukocytes, Mononuclear/pathology , Mice , Mice, Inbred C57BL , Muscle Strength/physiology , Mutation/genetics , Nerve Tissue Proteins/metabolism , Neurons/pathology , Frataxin
13.
J Clin Pathol ; 71(8): 695-701, 2018 Aug.
Article in English | MEDLINE | ID: mdl-29463577

ABSTRACT

AIMS: Histopathological tissue samples are being increasingly used as sources of nucleic acids in molecular pathology translational research. This study investigated the suitability of glioblastoma and control central nervous system (CNS) formalin-fixed paraffin embedded (FFPE) tissue-derived RNA for gene expression analyses. METHODS: Total RNA was extracted from control (temporal lobe resection tissue) and glioblastoma FFPE tissue samples. RNA purity (260/280 ratios) was determined and RNA integrity number (RIN) analysis was performed. RNA was subsequently used for RT-qPCR for two reference genes, 18S and GAPDH. RESULTS: Reference gene expression was equivalent between control and glioblastoma tissue when using RNA extracted from FFPE tissue, which has key implications for biological normalisation for CNS gene expression studies. There was a significant difference between the mean RIN values of control and glioblastoma FFPE tissue. There was no significant correlation between 260/280 or RIN values versus total RNA yield. The age of the tissue blocks did not influence RNA yield, fragmentation or purity. There was no significant correlation between RIN or 260/280 ratios and mean qPCR cycle threshold for either reference gene. CONCLUSIONS: This study showed that routinely available CNS FFPE tissue is suitable for RNA extraction and downstream gene expression studies, even after 60 months of storage. Substantial RNA fragmentation associated with glioblastoma and control FFPE tissue blocks did not preclude downstream RT-qPCR gene expression analyses. Cross validation with both archival and prospectively collated FFPE specimens is required to further demonstrate that CNS tissue blocks can be used in novel translational molecular biomarker studies.


Subject(s)
Brain Neoplasms/genetics , Epilepsy, Temporal Lobe/genetics , Fixatives/chemistry , Formaldehyde/chemistry , Gene Expression Profiling , Glioblastoma/genetics , Paraffin Embedding , RNA Stability , RNA, Neoplasm/genetics , Tissue Fixation/methods , Brain Neoplasms/surgery , Case-Control Studies , Epilepsy, Temporal Lobe/surgery , Gene Expression Profiling/standards , Glioblastoma/surgery , Humans , Paraffin Embedding/standards , Predictive Value of Tests , Quality Control , Reproducibility of Results , Time Factors , Tissue Fixation/standards
14.
Mult Scler ; 24(7): 919-931, 2018 06.
Article in English | MEDLINE | ID: mdl-28548004

ABSTRACT

BACKGROUND: Autologous bone-marrow-derived cells are currently employed in clinical studies of cell-based therapy in multiple sclerosis (MS) although the bone marrow microenvironment and marrow-derived cells isolated from patients with MS have not been extensively characterised. OBJECTIVES: To examine the bone marrow microenvironment and assess the proliferative potential of multipotent mesenchymal stromal cells (MSCs) in progressive MS. METHODS: Comparative phenotypic analysis of bone marrow and marrow-derived MSCs isolated from patients with progressive MS and control subjects was undertaken. RESULTS: In MS marrow, there was an interstitial infiltrate of inflammatory cells with lymphoid (predominantly T-cell) nodules although total cellularity was reduced. Controlling for age, MSCs isolated from patients with MS had reduced in vitro expansion potential as determined by population doubling time, colony-forming unit assay, and expression of ß-galactosidase. MS MSCs expressed reduced levels of Stro-1 and displayed accelerated shortening of telomere terminal restriction fragments (TRF) in vitro. CONCLUSION: Our results are consistent with reduced proliferative capacity and ex vivo premature ageing of bone-marrow-derived cells, particularly MSCs, in MS. They have significant implication for MSC-based therapies for MS and suggest that accelerated cellular ageing and senescence may contribute to the pathophysiology of progressive MS.


Subject(s)
Cell Proliferation , Cellular Senescence , Mesenchymal Stem Cells/pathology , Multiple Sclerosis/pathology , Adult , Cell Proliferation/physiology , Cells, Cultured , Cellular Senescence/physiology , Female , Humans , Male , Middle Aged , Stem Cell Niche/physiology
15.
Cytotherapy ; 20(1): 21-28, 2018 01.
Article in English | MEDLINE | ID: mdl-28917625

ABSTRACT

BACKGROUND: Clinical trials using ex vivo expansion of autologous mesenchymal stromal cells (MSCs) are in progress for several neurological diseases including multiple sclerosis (MS). Given that environment alters MSC function, we examined whether in vitro expansion, increasing donor age and progressive MS affect the neuroprotective properties of the MSC secretome. METHODS: Comparative analyses of neuronal survival in the presence of MSC-conditioned medium (MSCcm) isolated from control subjects (C-MSCcm) and those with MS (MS-MSCcm) were performed following (1) trophic factor withdrawal and (2) nitric oxide-induced neurotoxicity. RESULTS: Reduced neuronal survival following trophic factor withdrawal was seen in association with increasing expansion of MSCs in vitro and MSC donor age. Controlling for these factors, there was an independent, negative effect of progressive MS. In nitric oxide neurotoxicity, MSCcm-mediated neuroprotection was reduced when C-MSCcm was isolated from higher-passage MSCs and was negatively associated with increasing MSC passage number and donor age. Furthermore, the neuroprotective effect of MSCcm was lost when MSCs were isolated from patients with MS. DISCUSSION: Our findings have significant implications for MSC-based therapy in neurodegenerative conditions, particularly for autologous MSC therapy in MS. Impaired neuroprotection mediated by the MSC secretome in progressive MS may reflect reduced reparative potential of autologous MSC-based therapy in MS and it is likely that the causes must be addressed before the full potential of MSC-based therapy is realized. Additionally, we anticipate that understanding the mechanisms responsible will contribute new insights into MS pathogenesis and may also be of wider relevance to other neurodegenerative conditions.


Subject(s)
Aging/pathology , Disease Progression , Mesenchymal Stem Cells/metabolism , Multiple Sclerosis/pathology , Multiple Sclerosis/therapy , Neuroprotective Agents/metabolism , Cell Proliferation/drug effects , Cell Survival/drug effects , Culture Media, Conditioned/pharmacology , Humans , Middle Aged , Neurons/drug effects , Neurons/metabolism , Neurons/pathology , Neuroprotection/drug effects , Nitric Oxide/metabolism
16.
Cerebellum ; 16(4): 840-851, 2017 08.
Article in English | MEDLINE | ID: mdl-28456899

ABSTRACT

Friedreich's ataxia is an inherited neurological disorder characterised by mitochondrial dysfunction and increased susceptibility to oxidative stress. At present, no therapy has been shown to reduce disease progression. Strategies being trialled to treat Friedreich's ataxia include drugs that improve mitochondrial function and reduce oxidative injury. In addition, stem cells have been investigated as a potential therapeutic approach. We have used siRNA-induced knockdown of frataxin in SH-SY5Y cells as an in vitro cellular model for Friedreich's ataxia. Knockdown of frataxin protein expression to levels detected in patients with the disorder was achieved, leading to decreased cellular viability, increased susceptibility to hydrogen peroxide-induced oxidative stress, dysregulation of key anti-oxidant molecules and deficiencies in both cell proliferation and differentiation. Bone marrow stem cells are being investigated extensively as potential treatments for a wide range of neurological disorders, including Friedreich's ataxia. The potential neuroprotective effects of bone marrow-derived mesenchymal stem cells were therefore studied using our frataxin-deficient cell model. Soluble factors secreted by mesenchymal stem cells protected against cellular changes induced by frataxin deficiency, leading to restoration in frataxin levels and anti-oxidant defences, improved survival against oxidative stress and stimulated both cell proliferation and differentiation down the Schwann cell lineage. The demonstration that mesenchymal stem cell-derived factors can restore cellular homeostasis and function to frataxin-deficient cells further suggests that they may have potential therapeutic benefits for patients with Friedreich's ataxia.


Subject(s)
Friedreich Ataxia/metabolism , Iron-Binding Proteins/metabolism , Mesenchymal Stem Cells/metabolism , Cell Differentiation/physiology , Cell Line, Tumor , Cell Proliferation/physiology , Cell Survival/physiology , Femur , Gene Knockdown Techniques , Homeostasis/physiology , Humans , Hydrogen Peroxide/metabolism , Iron-Binding Proteins/genetics , Nitric Oxide/metabolism , Oxidative Stress/physiology , RNA, Small Interfering , Schwann Cells/metabolism , Frataxin
17.
Cancer Res ; 77(6): 1383-1394, 2017 03 15.
Article in English | MEDLINE | ID: mdl-28115363

ABSTRACT

Obesity increases the risk of distant metastatic recurrence and reduces breast cancer survival. However, the mechanisms behind this pathology and identification of relevant therapeutic targets are poorly defined. Plasma free fatty acids (FFA) levels are elevated in obese individuals. Here we report that TGFß transiently activates ERK and subsequently phosphorylates SMAD4 at Thr277, which facilitates a SMAD4-USP9x interaction, SMAD4 nuclear retention, and stimulates TGFß/SMAD3-mediated transcription of Twist and Snail. USP9x inhibited the E3 ubiquitin-protein ligase TIF1γ from binding and monoubiquitinating SMAD4, hence maintaining the SMAD4 nuclear retention. FFA further facilitated TGFß-induced ERK activation, SMAD4 phosphorylation, and nuclear retention, promoting TGFß-dependent cancer progression. Inhibition of ERK and USP9x suppressed obesity-induced metastasis. In addition, clinical data indicated that phospho-ERK and -SMAD4 levels correlate with activated TGFß signaling and metastasis in overweight/obese patient breast cancer specimens. Altogether, we demonstrate the vital interaction of USP9x and SMAD4 for governing TGFß signaling and dyslipidemia-induced aberrant TGFß activation during breast cancer metastasis. Cancer Res; 77(6); 1383-94. ©2017 AACR.


Subject(s)
Biomarkers, Tumor/metabolism , Breast Neoplasms/pathology , Fatty Acids, Nonesterified/pharmacology , Lung Neoplasms/secondary , Smad4 Protein/metabolism , Transforming Growth Factor beta/metabolism , Ubiquitin Thiolesterase/metabolism , Animals , Apoptosis , Breast Neoplasms/drug therapy , Breast Neoplasms/metabolism , Cell Movement , Cell Proliferation , Female , Humans , Lung Neoplasms/drug therapy , Lung Neoplasms/metabolism , Mice , Mice, Nude , Obesity/physiopathology , Phosphorylation , Signal Transduction , Tumor Cells, Cultured , Ubiquitination
18.
Histopathology ; 70(7): 1030-1043, 2017 Jun.
Article in English | MEDLINE | ID: mdl-27926792

ABSTRACT

AIMS: PPARα agonists are in current clinical use as hypolipidaemic agents and show significant antineoplastic effects in human glioblastoma models. To date however, the expression of PPARα in large-scale glioblastoma datasets has not been examined. We aimed to investigate the expression of the transcription factor PPARα in primary glioblastoma, the relationship between PPARα expression and patients' clinicopathological features and other molecular markers associated with gliomagenesis. METHODS AND RESULTS: With protein immunoblotting techniques and reverse transcription quantitative real-time PCR, PPARα was found to be significantly overexpressed in glioblastoma compared with control brain tissue (P = 0.032 and P = 0.005). PPARA gene expression was found to be enriched in the classical glioblastoma subtype within The Cancer Genome Atlas (TCGA) dataset. Although not associated with overall survival when assessed by immunohistochemistry, cross-validation with the TCGA dataset and multivariate analyses identified PPARA gene expression as an independent prognostic marker for overall survival (P = 0.042). Finally, hierarchical clustering revealed novel, significant associations between high PPARA expression and a putative set of glioblastoma molecular mediators including EMX2, AQP4, and NTRK2. CONCLUSIONS: PPARα is overexpressed in primary glioblastoma and high PPARA expression functions as an independent prognostic marker in the glioblastoma TCGA dataset. Further studies are required to explore genetic associations with high PPARA expression and to analyse the predictive role of PPARα expression in glioblastoma models in response to PPARα agonists.


Subject(s)
Biomarkers, Tumor/analysis , Brain Neoplasms/pathology , Glioblastoma/pathology , PPAR alpha/biosynthesis , Adult , Aged , Aged, 80 and over , Brain Neoplasms/metabolism , Brain Neoplasms/mortality , Child , Female , Glioblastoma/metabolism , Glioblastoma/mortality , Humans , Isocitrate Dehydrogenase/genetics , Kaplan-Meier Estimate , Male , Middle Aged , PPAR alpha/analysis , Prognosis , Proportional Hazards Models
19.
Ann Neurol ; 81(2): 212-226, 2017 Feb.
Article in English | MEDLINE | ID: mdl-28009062

ABSTRACT

OBJECTIVES: Friedreich's ataxia is a devastating neurological disease currently lacking any proven treatment. We studied the neuroprotective effects of the cytokines, granulocyte-colony stimulating factor (G-CSF) and stem cell factor (SCF) in a humanized murine model of Friedreich's ataxia. METHODS: Mice received monthly subcutaneous infusions of cytokines while also being assessed at monthly time points using an extensive range of behavioral motor performance tests. After 6 months of treatment, neurophysiological evaluation of both sensory and motor nerve conduction was performed. Subsequently, mice were sacrificed for messenger RNA, protein, and histological analysis of the dorsal root ganglia, spinal cord, and cerebellum. RESULTS: Cytokine administration resulted in significant reversal of biochemical, neuropathological, neurophysiological, and behavioural deficits associated with Friedreich's ataxia. Both G-CSF and SCF had pronounced effects on frataxin levels (the primary molecular defect in the pathogenesis of the disease) and a regulators of frataxin expression. Sustained improvements in motor coordination and locomotor activity were observed, even after onset of neurological symptoms. Treatment also restored the duration of sensory nerve compound potentials. Improvements in peripheral nerve conduction positively correlated with cytokine-induced increases in frataxin expression, providing a link between increases in frataxin and neurophysiological function. Abrogation of disease-related pathology was also evident, with reductions in inflammation/gliosis and increased neural stem cell numbers in areas of tissue injury. INTERPRETATION: These experiments show that cytokines already clinically used in other conditions offer the prospect of a novel, rapidly translatable, disease-modifying, and neuroprotective treatment for Friedreich's ataxia. Ann Neurol 2017;81:212-226.


Subject(s)
Behavior, Animal/drug effects , Friedreich Ataxia/drug therapy , Granulocyte Colony-Stimulating Factor/pharmacology , Iron-Binding Proteins/metabolism , Neural Conduction/drug effects , Neuroprotective Agents/pharmacology , Peripheral Nerves/drug effects , Stem Cell Factor/pharmacology , Animals , Disease Models, Animal , Friedreich Ataxia/metabolism , Friedreich Ataxia/physiopathology , Granulocyte Colony-Stimulating Factor/administration & dosage , Humans , Mice , Mice, Inbred C57BL , Mice, Transgenic , Neuroprotective Agents/administration & dosage , Stem Cell Factor/administration & dosage , Frataxin
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