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1.
BMC Neurosci ; 19(1): 20, 2018 04 12.
Artículo en Inglés | MEDLINE | ID: mdl-29649974

RESUMEN

BACKGROUND: Stroke is a leading cause of death and disability worldwide, yet there are limited treatments available. Intranasal administration is a novel non-invasive strategy to deliver cell therapy into the brain. Cells delivered via the intranasal route can migrate from the nasal mucosa to the ischemic infarct and show acute neuroprotection as well as functional benefits. However, there is little information about the regenerative effects of this transplantation method in the delayed phase of stroke. We hypothesized that repeated intranasal deliveries of bone marrow stromal cells (BMSCs) would be feasible and could enhance delayed neurovascular repair and functional recovery after ischemic stroke. RESULTS: Reverse transcription polymerase chain reaction and immunocytochemistry were performed to analyze the expression of regenerative factors including SDF-1α, CXCR4, VEGF and FAK in BMSCs. Ischemic stroke targeting the somatosensory cortex was induced in adult C57BL/6 mice by permanently occluding the right middle cerebral artery and temporarily occluding both common carotid arteries. Hypoxic preconditioned (HP) BMSCs (HP-BMSCs) with increased expression of surviving factors HIF-1α and Bcl-xl (1 × 106 cells/100 µl per mouse) or cell media were administered intranasally at 3, 4, 5, and 6 days after stroke. Mice received daily BrdU (50 mg/kg) injections until sacrifice. BMSCs were prelabeled with Hoechst 33342 and detected within the peri-infarct area 6 and 24 h after transplantation. In immunohistochemical staining, significant increases in NeuN/BrdU and Glut-1/BrdU double positive cells were seen in stroke mice received HP-BMSCs compared to those received regular BMSCs. HP-BMSC transplantation significantly increased local cerebral blood flow and improved performance in the adhesive removal test. CONCLUSIONS: This study suggests that delayed and repeated intranasal deliveries of HP-treated BMSCs is an effective treatment to encourage regeneration after stroke.


Asunto(s)
Isquemia Encefálica/terapia , Precondicionamiento Isquémico , Trasplante de Células Madre Mesenquimatosas , Neurogénesis/fisiología , Recuperación de la Función/fisiología , Administración Intranasal , Animales , Células de la Médula Ósea/citología , Células Cultivadas , Células Madre Mesenquimatosas/citología , Ratones , Ratones Endogámicos C57BL , Accidente Cerebrovascular/terapia
2.
Stem Cells ; 32(12): 3075-87, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25132189

RESUMEN

Limited treatments are available for perinatal/neonatal stroke. Induced pluripotent stem cells (iPSCs) hold therapeutic promise for stroke treatment, but the benefits of iPSC transplantation in neonates are relatively unknown. We hypothesized that transplanted iPSC-derived neural progenitor cells (iPSC-NPCs) would increase regeneration after stroke. Mouse pluripotent iPSCs were differentiated into neural progenitors using a retinoic acid protocol. Differentiated neural cells were characterized by using multiple criteria and assessments. Ischemic stroke was induced in postnatal day 7 (P7) rats by occluding the right middle cerebral artery and right common carotid artery. iPSC-NPCs (400,000 in 4 µl) were transplanted into the penumbra via intracranial injection 7 days after stroke. Trophic factor expression in the peri-infarct tissue was measured using Western blot analysis. Animals received daily bromodeoxyuridine (BrdU) injections and were sacrificed 21 days after stroke for immunohistochemistry. The vibrissae-elicited forelimb placement test was used to evaluate functional recovery. Differentiated iPSCs expressed mature neuronal markers, functional sodium and potassium channels, and fired action potentials. Several angiogenic and neurogenic trophic factors were identified in iPSC-NPCs. Animals that received iPSC-NPC transplantation had greater expression of stromal cell-derived factor 1-α (SDF-1α) and vascular endothelial growth factor (VEGF) in the peri-infarct region. iPSC-NPCs stained positive for neuronal nuclei (NeuN) or glial fibrillary acidic protein (GFAP) 14 days after transplantation. iPSC-NPC-transplanted animals showed greater numbers of BrdU/NeuN and BrdU/Collagen IV colabeled cells in the peri-infarct area compared with stroke controls and performed better in a sensorimotor functional test after stroke. iPSC-NPC therapy may play multiple therapeutic roles after stroke by providing trophic factors, increasing angiogenesis and neurogenesis, and providing new cells for tissue repair.


Asunto(s)
Isquemia Encefálica/terapia , Células Madre Pluripotentes Inducidas/citología , Células-Madre Neurales/citología , Recuperación de la Función/fisiología , Accidente Cerebrovascular/terapia , Animales , Animales Recién Nacidos , Diferenciación Celular/fisiología , Células Cultivadas , Modelos Animales de Enfermedad , Células Madre Pluripotentes Inducidas/trasplante , Ratones , Neurogénesis/fisiología , Ratas , Factor A de Crecimiento Endotelial Vascular/metabolismo
3.
PLoS One ; 17(11): e0260998, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36417411

RESUMEN

Regeneration after severe peripheral nerve injury is often poor. Knowledge of human nerve regeneration and the growth microenvironment is greatly lacking. We aimed to identify the regenerative proteins in human peripheral nerve by comparing the proteome before and after a transection injury. In a unique study design, we collected closely matched samples of naïve and injured sural nerve. Naïve and injured (two weeks after injury) samples were analyzed using mass spectrometry and immunoassays. We found significantly altered levels following the nerve injury. Mass spectrometry revealed that injury samples had 568 proteins significantly upregulated and 471 significantly downregulated compared to naïve samples (q-value ≤ 0.05 and Z ≥ |2| (log2)). We used Gene Ontology (GO) pathway overrepresentation analysis to highlight groups of proteins that were significantly upregulated or downregulated with injury-induced degeneration and regeneration. Significant protein changes in key pathways were identified including growth factor levels, Schwann cell de-differentiation, myelination downregulation, epithelial-mesenchymal transition (EMT), and axonal regeneration pathways. The proteomes of the uninjured nerve compared to the degenerating/regenerating nerve may reveal biomarkers to aid in the development of repair strategies such as infusing supplemental trophic factors and in monitoring neural tissue regeneration.


Asunto(s)
Traumatismos de los Nervios Periféricos , Proteoma , Humanos , Nervio Sural , Regeneración Nerviosa/fisiología , Nervios Periféricos
4.
Cell Transplant ; 31: 9636897221123515, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36169034

RESUMEN

One promising strategy in cell therapies for Parkinson's disease (PD) is to harness a patient's own cells to provide neuroprotection in areas of the brain affected by neurodegeneration. No treatment exists to replace cells in the brain. Thus, our goal has been to support sick neurons and slow neurodegeneration by transplanting living repair tissue from the peripheral nervous system into the substantia nigra of those with PD. Our group has pioneered the transplantation of transection-activated sural nerve fascicles into the brain of human subjects with PD. Our experience in sural nerve transplantation has supported the safety and feasibility of this approach. As part of a paradigm to assess the reparative properties of human sural nerve following a transection injury, we collected nerve tissue approximately 2 weeks after sural nerve transection for immunoassays from 15 participants, and collected samples from two additional participants for single nuclei RNA sequencing. We quantified the expression of key neuroprotective and select anti-apoptotic genes along with their corresponding protein levels using immunoassays. The single nuclei data clustered into 10 distinctive groups defined on the basis of previously published cell type-specific genes. Transection-induced reparative peripheral nerve tissue showed RNA expression of neuroprotective factors and anti-apoptotic factors across multiple cell types after nerve injury induction. Key proteins of interest (BDNF, GDNF, beta-NGF, PDGFB, and VEGF) were upregulated in reparative tissue. These results provide insight on this repair tissue's utility as a neuroprotective cell therapy.


Asunto(s)
Factor de Crecimiento Nervioso , Enfermedad de Parkinson , Factor Neurotrófico Derivado del Encéfalo , Tratamiento Basado en Trasplante de Células y Tejidos , Factor Neurotrófico Derivado de la Línea Celular Glial/genética , Humanos , Enfermedad de Parkinson/terapia , Proteínas Proto-Oncogénicas c-sis , ARN , Factor A de Crecimiento Endotelial Vascular
5.
J Neurosurg ; : 1-10, 2022 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-36681977

RESUMEN

OBJECTIVE: The aims of this study were to quantify inpatient healthcare costs, describe patient demographics, and analyze variables influencing costs for pediatric and adult hydrocephalus shunt-related admissions in the US. METHODS: A cross-sectional study was performed using the 2019 Healthcare Cost and Utilization Project Kids' Inpatient Database (KID) and National Inpatient Sample (NIS), nationally representative weighted data sets of hospital discharges for pediatric and adult patients, respectively. International Classification of Diseases, 10th Revision, Clinical Modification and Procedure Coding System (ICD-10-CM/PCS) code filters for data extraction were queried for admission information. Age at admission was categorized into five groups (≤ 28 days, 29 days to < 1 year, 1-18 years, 19-64 years, and ≥ 65 years). RESULTS: In 2019, there were 36,898 shunt-related hospital admissions accounting for 495,138 hospital days and a total cost of more than $2.06 billion. Initial shunt placements accounted for 53.5% of all admissions and nearly 60% of the total cost. The median cost per admission was $22,700 and the median length of stay was 5 days. Admissions for shunt infection requiring revision had the highest median cost at $71,300 (p < 0.001) and the longest median length of stay at 25 days (p < 0.001) compared with initial shunt placements. By age, admissions that occurred in the first 28 days of life cost almost 5 times more than the median, $110,500 versus $22,700, respectively, and resulted in hospital stays that were 8 times longer than the median, 41 versus 5 days, respectively. Individuals aged ≥ 65 years accounted for 28% of the total shunt-related admissions. Almost two-thirds (65.3%) of shunt-related admissions were classified as nonelective. The median cost of nonelective procedures was double that of elective admissions, $33,900 versus $15,100, respectively (p < 0.001), and resulted in almost 5 times longer hospital stays, 9 versus 2 days, respectively (p < 0.001). Shunt-related admissions were predominantly male across all age groups (54.7%-57.4% male) except the 19- to 64-year age group. In the 19- to 64-year age group, females accounted for 51.1% of admissions. Insurance status was largely age dependent. Of all admissions, 33.1% used private insurance, 32.9% Medicare, and 27.7% Medicaid. CONCLUSIONS: This is the first study to quantify the patient demographics and cost of hydrocephalus shunt-related admissions across the entire age spectrum. Shunt-related admissions cost the US more than $2.06 billion dollars per year and represent only a fraction of the total cost of hydrocephalus care.

6.
BMJ Neurol Open ; 4(2): e000301, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35949912

RESUMEN

Objective: To evaluate the interim feasibility, safety and clinical measures data of direct delivery of regenerating peripheral nerve tissue (PNT) to the substantia nigra (SN) in participants with Parkinson's disease (PD). Methods: Eighteen (13 men/5 women) participants were unilaterally implanted with PNT to the SN, contralateral to the most affected side during the same surgery they were receiving deep brain stimulation (DBS) surgery. Autologous PNT was collected from the sural nerve. Participants were followed for safety and clinical outcomes for 2 years (including off-state Unified Parkinson's Disease Rating Scale (UPDRS) Part III assessments) with study visits every 6 months. Results: All 18 participants scheduled to receive PNT implantation received targeted delivery to the SN in addition to their DBS. All subjects were discharged the following day except for two: post-op day 2; post-op day 3. The most common study-related adverse events were hypoaesthesia and hyperaesthesias to the lateral aspect of the foot and ankle of the biopsied nerve (6 of 18 participants experienced). Clinical measures did not identify any hastening of PD measures providing evidence of safety and tolerability. Off-state UPDRS Part III mean difference scores were reduced at 12 months compared with baseline (difference=-8.1, 95% CI -2.4 to -13.9 points, p=0.005). No complications involving dyskinesias were observed. Conclusions: Targeting the SN for direct delivery of PNT was feasible with no serious adverse events related to the study intervention. Interim clinical outcomes show promising results meriting continued examination of this investigational approach. Trial registration number: NCT02369003.

7.
Acta Neurochir Suppl ; 111: 299-305, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21725772

RESUMEN

Stroke affects infants at a rate of 26/100,000 live births each year. Of these strokes, approximately 6.7 are hemorrhagic strokes. Erythropoietin (EPO) is an anti-apoptotic and neuroprotective hormone. In adult rodents, EPO attenuates inflammatory factor expression and blood-brain barrier damage after intracerebral hemorrhage (ICH). However, the effect of EPO in neonatal ICH stroke remains unexplored. This investigation aimed to elucidate the underpinnings of inflammation after ICH in postnatal day 7 (P7) rats and the effect of human recombinant EPO (hrEPO) treatment on ICH-induced inflammation. The P7 rat pups were pretreated with hrEPO (5,000 U/kg i.p.) or saline vehicle 4 h prior to the induction of ICH by blood injection into the right cerebral cortex and basal ganglia. Supplemental half doses of hrEPO treatment or saline injections were subsequently given 16 h after ICH induction. Real-time PCR done 24 h after ICH showed reductions in interleukin1-ß (IL1-ß), interleukin-6 (IL-6) and tumor necrosis factor-α (TNFα) mRNA expression in the basal ganglia of the hrEPO-treated rats compared to saline-treated rats. Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining indicated fewer dying cells in the hrEPO-treated brain. Our data suggest that hrEPO has an anti-inflammatory action in neonates after ICH. The suppression of inflammatory cascades likely contributes to hrEPO's neuroprotective effect, which may be explored as a therapeutic treatment for ICH.


Asunto(s)
Hemorragia Cerebral/complicaciones , Eritropoyetina/uso terapéutico , Inflamación/tratamiento farmacológico , Inflamación/etiología , Análisis de Varianza , Animales , Animales Recién Nacidos , Muerte Celular/efectos de los fármacos , Muerte Celular/fisiología , Citocinas/genética , Citocinas/metabolismo , Modelos Animales de Enfermedad , Eritropoyetina/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Etiquetado Corte-Fin in Situ , ARN Mensajero/metabolismo , Ratas , Ratas Wistar
8.
World Neurosurg ; 152: e617-e624, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34129978

RESUMEN

BACKGROUND: The COVID-19 pandemic has shifted the dynamics of health care and neurosurgical practice. Elective surgeries were suspended for 8 weeks in Kentucky. Our objective was to determine if telehealth (TH) visits could be sustained as an alternative to in-person visits. METHODS: Deidentified data on TH usage, in-person clinic visits, and inpatient and neurosurgical case volumes from March 2, 2020 to June 26, 2020 were obtained for retrospective analysis. RESULTS: TH use increased soon after the case suspension started and then decreased to little usage. The number of in-person visits were significantly lower during elective case suspension compared with when cases were resumed. Twenty-five percent of all visits during the suspension were conducted using TH. Thirty-nine percent of TH-visit patients were new patients, 11% were preoperative, 10% were postoperative, and 39% were other existing patients. Forty-eight percent of TH visits resulted in a later in-person clinic visit. After the suspension, in-person visits rebounded to 98% of the prepandemic numbers and TH visits were low. CONCLUSIONS: TH visits were challenging due to the need for in-person physical examinations in neurosurgery. TH temporarily accommodated patient needs during the pandemic but could not totally replace in-person visits and was not sustained after 3.5 months of use. Video TH visits worked well for nonurgent issues, such as minor visual examinations. Our findings could help guide the implementation of TH should similar circumstances arise again.


Asunto(s)
COVID-19/cirugía , Neurocirugia , Procedimientos Neuroquirúrgicos , Telemedicina , Adulto , Atención Ambulatoria/estadística & datos numéricos , Atención a la Salud/estadística & datos numéricos , Humanos , Pacientes Internos/estadística & datos numéricos , Masculino , Estudios Retrospectivos , SARS-CoV-2/patogenicidad
9.
Brain Sci ; 11(4)2021 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-33921079

RESUMEN

BACKGROUND: The efficacy of deep brain stimulation (DBS) and dopaminergic therapy is known to decrease over time. Hence, a new investigational approach combines implanting autologous injury-activated peripheral nerve grafts (APNG) at the time of bilateral DBS surgery to the globus pallidus interna. OBJECTIVES: In a study where APNG was unilaterally implanted into the substantia nigra, we explored the effects on clinical gait and balance assessments over two years in 14 individuals with Parkinson's disease. METHODS: Computerized gait and balance evaluations were performed without medication, and stimulation was in the off state for at least 12 h to best assess the role of APNG implantation alone. We hypothesized that APNG might improve gait and balance deficits associated with PD. RESULTS: While people with a degenerative movement disorder typically worsen with time, none of the gait parameters significantly changed across visits in this 24 month study. The postural stability item in the UPDRS did not worsen from baseline to the 24-month follow-up. However, we measured gait and balance improvements in the two most affected individuals, who had moderate PD. In these two individuals, we observed an increase in gait velocity and step length that persisted over 6 and 24 months. CONCLUSIONS: Participants did not show worsening of gait and balance performance in the off therapy state two years after surgery, while the two most severely affected participants showed improved performance. Further studies may better address the long-term maintanenace of these results.

10.
Cancer Epidemiol ; 60: 16-22, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30878798

RESUMEN

BACKGROUND: Meningiomas are the most common central nervous system tumor. We describe current trends in treatment and survival using the largest cancer dataset in the United States. METHODS: We analyzed the National Cancer Database from 2004 to 2014, for all patients with diagnosis of meningioma. RESULTS: 201,765 cases were analyzed. Patients were most commonly White (81.9%) females (73.2%) with a median age of 64 years. Fifty percent of patients were diagnosed by imaging. Patients were reported as grade I (24.9%), grade II (5.0%), grade III (0.7%), or unknown WHO grade (69.4%). Patients diagnosed by imaging were older, received treatment in community facilities, had higher Charlson-Deyo score, and a lower rate of private insurance. Watchful waiting was the most common treatment modality (46.7%), followed by surgery only (40%). Grade II and III patients were more likely to receive therapy. Watchful waiting increased from 35.2% in 2004 to 51.4% in 2014. Younger age, male gender, private insurance, and treatment in academic facilities were determinants for receipt of surgery and/or radiation. Median survival was 12.6 years, higher in histologically confirmed cases (13.1 years). Older patients, Blacks, males, those that received radiation plus surgery, and were treated in community facilities had an increased risk of mortality. CONCLUSIONS: Over half of patients were diagnosed by imaging, suggesting a higher role of clinical determinants over histological confirmation in treatment decisions. Watchful waiting as initial management is increasing. Our survival analysis favored histological confirmation. Patients receiving radiation and surgery had an increased risk of mortality.


Asunto(s)
Bases de Datos Factuales , Neoplasias Meníngeas/terapia , Meningioma/terapia , Espera Vigilante , Adolescente , Adulto , Anciano , Niño , Preescolar , Terapia Combinada , Manejo de la Enfermedad , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Neoplasias Meníngeas/mortalidad , Neoplasias Meníngeas/patología , Meningioma/mortalidad , Meningioma/patología , Persona de Mediana Edad , Pronóstico , Factores de Riesgo , Factores Socioeconómicos , Tasa de Supervivencia , Estados Unidos , Adulto Joven
11.
Cell Rep ; 23(6): 1651-1664, 2018 05 08.
Artículo en Inglés | MEDLINE | ID: mdl-29742423

RESUMEN

Cancer stem cells promote neoplastic growth, in part by deregulating asymmetric cell division and enhancing self-renewal. To uncover mechanisms and potential therapeutic targets in glioma stem cell (GSC) self-renewal, we performed a genetic suppressor screen for kinases to reverse the tumor phenotype of our Drosophila brain tumor model and identified dCdk5 as a critical regulator. CDK5, the human ortholog of dCdk5 (79% identity), is aberrantly activated in GBMs and tightly aligned with both chromosome 7 gains and stem cell markers affecting tumor-propagation. Our investigation revealed that pharmaceutical inhibition of CDK5 prevents GSC self-renewal in vitro and in xenografted tumors, at least partially by suppressing CREB1 activation independently of PKA/cAMP. Finally, our TCGA GBM data analysis revealed that CDK5, stem cell, and asymmetric cell division markers segregate within non-mesenchymal patient clusters, which may indicate preferential dependence on CDK5 signaling and sensitivity to its inhibition in this group.


Asunto(s)
Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Quinasa 5 Dependiente de la Ciclina/antagonistas & inhibidores , Proteínas de Drosophila/antagonistas & inhibidores , Glioma/metabolismo , Glioma/patología , Células Madre Neoplásicas/patología , Transducción de Señal , Animales , División Celular Asimétrica/efectos de los fármacos , Biomarcadores de Tumor/metabolismo , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Proliferación Celular/efectos de los fármacos , Autorrenovación de las Células/efectos de los fármacos , Quinasa 5 Dependiente de la Ciclina/genética , Quinasa 5 Dependiente de la Ciclina/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Glioma/genética , Mesodermo/efectos de los fármacos , Mesodermo/patología , Ratones , Células Madre Neoplásicas/efectos de los fármacos , Células Madre Neoplásicas/metabolismo , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Neuronas/patología , Fosforilación/efectos de los fármacos , Unión Proteica/efectos de los fármacos , Inhibidores de Proteínas Quinasas/farmacología , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto
12.
Oncotarget ; 8(57): 97537-97553, 2017 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-29228630

RESUMEN

Ischemic stroke is a leading cause of human death and disability while clinical treatments are limited. The adult brain possesses endogenous regenerative activities that may benefit tissue repair after stroke. Trophic factors such as stromal cell-derived factor 1 alpha (SDF-1α) are upregulated in the ischemic brain, which promote endogenous regeneration. The regenerative response, however, is normally insufficient. Transplantation of exogenous cells has been explored as regenerative therapies. One promising cell type for transplantation is induced pluripotent stem (iPS) cells which are cells genetically reprogrammed from adult somatic cells. We hypothesized that transplanting neural progenitor cells derived from iPS cells (iPS-NPCs) could provide cell replacement and trophic support. The trophic factor SDF-1α was overexpressed in iPS-NPCs by lentiviral transduction to test if SDF-1α could increase regeneration in the ischemic brain. These SDF-1α-iPS-NPCs were differentiated in vitro to express mature neuronal and synaptic markers. Differentiated cells expressed functional Na+ and K+ channels, and fired action potentials. In the oxygen glucose deprivation (OGD) test, SDF-1α-iPS-NPCs survived significantly better compared to control iPS-NPCs. In mice subjected to focal cerebral ischemia in the sensorimotor cortex, iPS-NPCs and SDF-1α-iPS-NPCs were intracranially transplanted into the ischemic cortex 7 days after stroke. Neuronal differentiation of transplanted cells was identified using NeuN 14 days after transplantation. Mice that received SDF-1α-iPS-NPCs had greater numbers of NeuN/BrdU and Glut-1/BrdU co-labeled cells in the peri-infarct area and improved locomotion compared to the control iPS-NPC transplantation. Thus, SDF-1α upregulation in transplanted cells may be a therapeutic strategy to enhance endogenous neurovascular repair after ischemic stroke in adult mice.

13.
Mol Oncol ; 11(3): 280-294, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28100038

RESUMEN

Glioblastoma (GBM) is the most malignant form of primary brain tumor, and GBM stem-like cells (GSCs) contribute to the rapid growth, therapeutic resistance, and clinical recurrence of these fatal tumors. STAT3 signaling supports the maintenance and proliferation of GSCs, yet regulatory mechanisms are not completely understood. Here, we report that tri-partite motif-containing protein 8 (TRIM8) activates STAT3 signaling to maintain stemness and self-renewing capabilities of GSCs. TRIM8 (also known as 'glioblastoma-expressed ring finger protein') is expressed equally in GBM and normal brain tissues, despite its hemizygous deletion in the large majority of GBMs, and its expression is highly correlated with stem cell markers. Experimental knockdown of TRIM8 reduced GSC self-renewal and expression of SOX2, NESTIN, and p-STAT3, and promoted glial differentiation. Overexpression of TRIM8 led to higher expression of p-STAT3, c-MYC, SOX2, NESTIN, and CD133, and enhanced GSC self-renewal. We found that TRIM8 activates STAT3 by suppressing the expression of PIAS3, an inhibitor of STAT3, most likely through E3-mediated ubiquitination and proteasomal degradation. Interestingly, we also found that STAT3 activation upregulates TRIM8, providing a mechanism for normalized TRIM8 expression in the setting of hemizygous gene deletion. These data demonstrate that bidirectional TRIM8-STAT3 signaling regulates stemness in GSC.


Asunto(s)
Neoplasias Encefálicas/metabolismo , Encéfalo/patología , Proteínas Portadoras/metabolismo , Glioblastoma/metabolismo , Chaperonas Moleculares/metabolismo , Células Madre Neoplásicas/patología , Proteínas del Tejido Nervioso/metabolismo , Proteínas Inhibidoras de STAT Activados/metabolismo , Factor de Transcripción STAT3/metabolismo , Encéfalo/metabolismo , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Proteínas Portadoras/genética , Línea Celular , Línea Celular Tumoral , Proliferación Celular , Regulación Neoplásica de la Expresión Génica , Glioblastoma/genética , Glioblastoma/patología , Humanos , Chaperonas Moleculares/genética , Células Madre Neoplásicas/metabolismo , Proteínas del Tejido Nervioso/genética , Proteínas Inhibidoras de STAT Activados/genética , Interferencia de ARN , ARN Interferente Pequeño/genética , Factor de Transcripción STAT3/genética , Transducción de Señal
14.
Brain Circ ; 2(2): 86-94, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-30276278

RESUMEN

Stroke is a leading cause of death and disability worldwide. However, there is only one Food and Drug Administration-approved drug for the treatment of ischemic stroke, i.e., tissue plasminogen activator, and its therapeutic window is limited to within 4.5 h after stroke. Since clinical trials for neuroprotection have failed to demonstrate efficacy, multipotent and pluripotent stem cell transplantations are viable candidates for stroke treatment by providing trophic factor support and/or cell replacement following injury. The goal of this review is to highlight the promise of stem cell transplantation as vehicles for trophic factor delivery. The beneficial effects of different stem cell types as transplants as well as ways to upregulate trophic factors in stem cells are described in this review. Stem cell transplantation has consistently shown beneficial effects in the ischemic stroke model, in part due to the beneficial factors that stem cells release around the stroke injury area, resulting in smaller infarct volumes and regeneration and functional recovery. Upregulation of beneficial factors in stem cells and neural progenitors before transplantation has been shown to be even more effective in treating the stroke injury than stem cells without upregulated factors. However, for both stem cells and genetic engineering, there remain many unanswered questions and potential for improvement. These include modifiable parameters such as the different stem cell types and different factors, as well as the various readouts for investigation, such as various in vivo effects, such as immune system modulation and enhancement of endogenous neurogenesis and angiogenesis.

15.
J Occup Environ Med ; 44(2): 168-75, 2002 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11851218

RESUMEN

We observed 42,076 men and 11,706 women first employed at the Michigan locations of The Dow Chemical Company between 1940 and 1994. Follow-up was 98% complete, and we identified 16,242 deaths. Significant deficits in standardized mortality ratios were observed for all causes, all malignant neoplasms, and more than a dozen other causes of death when compared with rates in the United States. We observed significant elevations for several causes of death among employees of a magnesium foundry. There is little modern exposure information, because the foundry was sold nearly 40 years ago. This routine surveillance activity provided a generally favorable overview of the health experience of our employees and did not suggest a need for an additional focused study.


Asunto(s)
Causas de Muerte , Industria Química , Exposición Profesional , Salud Laboral , Adulto , Anciano , Estudios de Cohortes , Femenino , Humanos , Magnesio/efectos adversos , Masculino , Michigan/epidemiología , Persona de Mediana Edad , Estudios Retrospectivos
16.
Biomed Res Int ; 2014: 384342, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25105123

RESUMEN

Subarachnoid hemorrhage (SAH) can lead to devastating neurological outcomes, and there are few pharmacologic treatments available for treating this condition. Both animal and human studies provide evidence of inflammation being a driving force behind the pathology of SAH, leading to both direct brain injury and vasospasm, which in turn leads to ischemic brain injury. Several inflammatory mediators that are elevated after SAH have been studied in detail. While there is promising data indicating that blocking these factors might benefit patients after SAH, there has been little success in clinical trials. One of the key factors that complicates clinical trials of SAH is the variability of the initial injury and subsequent inflammatory response. It is likely that both genetic and environmental factors contribute to the variability of patients' post-SAH inflammatory response and that this confounds trials of anti-inflammatory therapies. Additionally, systemic inflammation from other conditions that affect patients with SAH could contribute to brain injury and vasospasm after SAH. Continuing work on biomarkers of inflammation after SAH may lead to development of patient-specific anti-inflammatory therapies to improve outcome after SAH.


Asunto(s)
Lesiones Encefálicas , Hemorragia Subaracnoidea , Vasoespasmo Intracraneal , Biomarcadores/metabolismo , Lesiones Encefálicas/etiología , Lesiones Encefálicas/metabolismo , Lesiones Encefálicas/patología , Lesiones Encefálicas/fisiopatología , Lesiones Encefálicas/terapia , Humanos , Inflamación/metabolismo , Inflamación/patología , Inflamación/fisiopatología , Inflamación/terapia , Mediadores de Inflamación/metabolismo , Hemorragia Subaracnoidea/complicaciones , Hemorragia Subaracnoidea/metabolismo , Hemorragia Subaracnoidea/patología , Hemorragia Subaracnoidea/fisiopatología , Hemorragia Subaracnoidea/terapia , Vasoespasmo Intracraneal/etiología , Vasoespasmo Intracraneal/metabolismo , Vasoespasmo Intracraneal/patología , Vasoespasmo Intracraneal/fisiopatología , Vasoespasmo Intracraneal/terapia
17.
J Otolaryngol ; 32(4): 226-9, 2003 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-14587561

RESUMEN

It has been shown that inhibition of cyclooxygenase 2 (COX-2) may cause growth arrest and reduced tumour formation in some human cancers; however, the mechanism is not fully known. In this study, we used an oral squamous cell carcinoma cell line to study growth inhibition and changes in critical cell cycle-regulating proteins induced by the selective COX-2 inhibitor celecoxib. Using cell viability assay, we established the optimal in vitro inhibitory dose of celecoxib and showed that inhibition of COX-2 markedly induces the expression of p27kip1, p21, waf1, and the F-box protein skp2. These results add new experimental data to our knowledge of the mechanism of cyclooxygenases on neoplastic cells.


Asunto(s)
Carcinoma de Células Escamosas/tratamiento farmacológico , Proteínas de Ciclo Celular/biosíntesis , Inhibidores de la Ciclooxigenasa/farmacología , Isoenzimas/antagonistas & inhibidores , Neoplasias de la Boca/tratamiento farmacológico , Proteínas Quinasas Asociadas a Fase-S/biosíntesis , Proteínas Supresoras de Tumor/biosíntesis , Carcinoma de Células Escamosas/metabolismo , Celecoxib , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Inhibidor p27 de las Quinasas Dependientes de la Ciclina , Ciclooxigenasa 2 , Inhibidores de la Ciclooxigenasa 2 , Inhibidores de la Ciclooxigenasa/uso terapéutico , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Técnicas In Vitro , Indometacina/farmacología , Indometacina/uso terapéutico , Proteínas de la Membrana , Neoplasias de la Boca/metabolismo , Prostaglandina-Endoperóxido Sintasas , Pirazoles , Sulfonamidas/farmacología , Sulfonamidas/uso terapéutico , Proteína p53 Supresora de Tumor/biosíntesis
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