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The modern technique of epineural suture repair, along with a detailed reporting of functional restoration, came from Carl Hueter in 1873. While there is extensive information on peripheral nerve surgery throughout recorded history leading up to the 1800s, little early American scientific literature is available. While Schwann, Nissl, and Waller were publishing their work on nerve anatomy and physiology, Francis LeJau Parker was born. The South Carolina native would go on to describe one of the first American cases of peripheral nerve repair with the restoration of function. Francis Parker was born in 1836 in Abbeville, South Carolina. He gained local notoriety as one of the first American surgeons to suture a severed nerve, resulting in restored function. The case dates back to 1880, when a patient presented to his clinic with severing of the posterior interosseous nerve. The details of this case come from the archives of the South Carolina Medical Association. The authors reviewed these records in detail and provide a case description of nerve repair not previously reported in the modern literature. The history, neurological examination, and details of the case provide insight into the adroit surgical skills of Dr. Parker.
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OBJECTIVE: Currarino Syndrome (CS) is a rare autosomal dominant genetic disorder that is defined by a triad of: presacral mass, anorectal malformations, and sacral bone dysplasia. Once discovered, these lesions are often surgically treated to avoid life threatening complications such as meningitis and malignant transformation of a sacral teratoma. As this syndrome is usually diagnosed in childhood, accurate diagnosis in adults presenting with this syndrome can be challenging and delay treatment. We present a case report with diagnostic and surgical management strategies of CS presenting in an elderly patient with accompanying review of literature. METHODS: We performed a literature review by searching PubMed, Ovid Embase, and Scopus electronic databases with the predetermined inclusion criteria of cases of CS in the adult population. RESULTS: A 70-year-old male with newly diagnosed CS and meningitis successfully underwent resection of his lesion as an interdisciplinary case between neurosurgery and colorectal surgery. At six-month follow up, the patient reports resolution of constipation and urinary symptoms, no longer has signs of infection, and remains neurologically full strength in his lower extremities. A review of literature revealed only 5 previously reported cases of CS presenting in the adult population with 3 of these cases requiring surgical intervention. CONCLUSION: Currarino Syndrome (CS) is an autosomal dominant genetic disorder characterized by a presacral mass, sacral bony deformities, and anorectal malformations. It is usually diagnosed in pediatric age group. In this article, we present a case of a 70-year-old male presenting with meningitis, encephalopathy, and gastrointestinal disturbances.
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Malformações Anorretais , Anormalidades do Sistema Digestório , Meningite , Doenças da Coluna Vertebral , Masculino , Adulto , Humanos , Criança , Idoso , Anormalidades do Sistema Digestório/complicações , Anormalidades do Sistema Digestório/diagnóstico , Anormalidades do Sistema Digestório/cirurgia , Canal Anal/cirurgia , Canal Anal/anormalidades , Sacro/cirurgiaRESUMO
Spinal cord injury (SCI) causes significant mortality and morbidity. Currently, no FDA-approved pharmacotherapy is available for treating SCI. Previously, low doses of estrogen (17ß-estradiol, E2) were shown to improve the post-injury outcome in a rat SCI model. However, the range of associated side effects makes advocating its therapeutic use difficult. Therefore, this study aimed at investigating the therapeutic efficacy of Premarin (PRM) in SCI. PRM is an FDA-approved E2 (10%) formulation, which is used for hormone replacement therapy with minimal risk of serious side effects. The effects of PRM on SCI were examined by magnetic resonance imaging, immunofluorescent staining, and western blot analysis in a rat model. SCI animals treated with vehicle alone, PRM, E2 receptor antagonist (ICI), or PRM + ICI were graded in a blinded way for locomotor function by using the Basso-Beattie-Bresnahan (BBB) locomotor scale. PRM treatment for 7 days decreased post-SCI lesion volume and attenuated neuronal cell death, inflammation, and axonal damage. PRM also altered the balance of pro- and anti-apoptotic proteins in favor of cell survival and improved angiogenesis and microvascular growth. Increased expression of estrogen receptors (ERs) ERα and ERß following PRM treatment and their inhibition by ER inhibitor indicated that the neuroprotection associated with PRM treatment might be E2-receptor mediated. The attenuation of glial activation with decreased inflammation and cell death, and increased angiogenesis by PRM led to improved functional outcome as determined by the BBB locomotor scale. These results suggest that PRM treatment has significant therapeutic implications for the improvement of post-SCI outcome.
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Estrogênios Conjugados (USP)/farmacologia , Doenças Neurodegenerativas/tratamento farmacológico , Traumatismos da Medula Espinal/tratamento farmacológico , Animais , Axônios/efeitos dos fármacos , Axônios/metabolismo , Modelos Animais de Doenças , Estradiol/metabolismo , Estrogênios/metabolismo , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Locomoção/efeitos dos fármacos , Masculino , Atividade Motora/efeitos dos fármacos , Doenças Neurodegenerativas/metabolismo , Neuroproteção/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica/efeitos dos fármacos , Medula Espinal/efeitos dos fármacos , Medula Espinal/metabolismo , Traumatismos da Medula Espinal/metabolismoRESUMO
BACKGROUND: Spinal epidural lipomatosis (SEL) is the excessive accumulation of extradural adipose tissue. Severe cases could result in myelopathy, and very rarely, in syringomyelia formation. Surgery has been associated with high morbidity and mortality, and no proven long-term benefits. The objective was to provide a technical description of an efficient and cost-effective procedure for multilevel thoracic decompression without requiring spinal instrumentation. METHODS: A technique of multilevel hemilaminotomy windows is described in a patient with severe thoracic SEL causing syringomyelia. A 3-dimensional spine model was created to illustrate the technique and working angles. We performed a literature review by searching PubMed, Ovid Embase, and Scopus electronic databases with the predetermined inclusion criteria of cases with spinal lipomatosis and a fluid cavity within the spinal cord. RESULTS: The patient's deficit and syringomyelia resolved postoperatively. A review of the literature revealed only 3 cases of syringomyelia secondary to SEL. Syringomyelia expansion occurred in all cases leading to progressive neurologic decline, and surgery with removal of the excessive adipose tissue resolved the syringomyelia and improved the neurologic functioning in all cases. CONCLUSIONS: This technique of multilevel alternating hemilaminotomy "windows" allows for safe and effective decompression and resection of the excessive adipose tissue with reduced operative time and without requiring spine instrumentation. The technique maintains the integrity of the posterior column, thus reducing the risk of postdecompression deformity. Careful bipolar electrocoagulation of internal vertebral veins and meticulous hemostasis is key for minimizing the intraoperative blood loss and avoiding postoperative hematoma formation.
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Descompressão Cirúrgica/métodos , Laminectomia/métodos , Compressão da Medula Espinal/cirurgia , Siringomielia/cirurgia , Vértebras Torácicas/cirurgia , Tecido Adiposo , Adulto , Espaço Epidural , Feminino , Humanos , Imageamento Tridimensional , Lipomatose/complicações , Imageamento por Ressonância Magnética , Compressão da Medula Espinal/diagnóstico por imagem , Compressão da Medula Espinal/etiologia , Compressão da Medula Espinal/fisiopatologia , Siringomielia/diagnóstico por imagem , Siringomielia/etiologia , Siringomielia/fisiopatologiaRESUMO
Spinal cord injury (SCI) patients sustain significant functional impairments; this is causally related to restricted neuronal regeneration after injury. The ensuing reactive gliosis, inflammatory cascade, and glial scar formation impede axonal regrowth. Although systemic anti-inflammatory agents (steroids) have been previously administered to counteract this, no current therapeutic is approved for post-injury neuronal regeneration, in part because of related side effects. Likewise, therapeutic systemic estrogen levels exhibit neuroprotective properties, but dose-dependent side effects are prohibitive. The current study thus uses low-dose estrogen delivery to the spinal cord injury (SCI) site using an agarose gel patch embedded with estrogen-loaded nanoparticles. Compared to controls, spinal cords from rodents treated with nanoparticle site-directed estrogen demonstrated significantly decreased post-injury lesion size, reactive gliosis, and glial scar formation. However, axonal regeneration, vascular endothelial growth factor production, and glial-cell-derived neurotrophic factor levels were increased with estrogen administration. Concomitantly improved locomotor and bladder functional recovery were observed with estrogen administration after injury. Therefore, low-dose site-directed estrogen may provide a future approach for enhanced neuronal repair and functional recovery in SCI patients.
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Estradiol/administração & dosagem , Estrogênios/administração & dosagem , Nanopartículas , Traumatismos da Medula Espinal/tratamento farmacológico , Animais , Modelos Animais de Doenças , Gliose/etiologia , Gliose/prevenção & controle , Masculino , Regeneração Nervosa , Tecido Parenquimatoso/patologia , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica , Traumatismos da Medula Espinal/patologia , Traumatismos da Medula Espinal/fisiopatologiaRESUMO
BACKGROUND: Dural reconstruction to achieve expansion duraplasty is important in suboccipital decompression for Chiari malformation type 1 (CM1). Although various dural substitutes are available, including synthetic collagen matrix grafts and dural xenografts, they have the potential to induce an inflammatory response. In this case series, the authors present their experience and discuss the incidence and possible mechanism of aseptic meningitis after the use of bovine collagen matrix graft as a dural substitute in patients with CM1 after suboccipital decompression. OBSERVATIONS: Three consecutive adult female patients who underwent suboccipital decompression at a single institution by a single neurosurgeon were retrospectively reviewed. They all presented with signs of aseptic meningitis in a delayed fashion, responded well to steroid administration, but had recurrence of their symptoms. Bovine collagen dural substitutes are resorbed in a process that induces an inflammatory response manifesting with signs of aseptic meningitis and is only alleviated with removal of the dural substitute. LESSONS: DuraMatrix Suturable, a dural xenograft derived from bovine dermis, though a viable choice for dural repair, is a potential cause of chemical meningitis after duraplasty in Chiari decompression surgery. In patients presenting with delayed and persistent aseptic meningitis after intervention, removal of this dural substitute led to improved symptomatology.
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Temozolomide (TMZ) therapy is the standard of care for patients with glioblastoma (GBM). Clinical studies have shown that elevated levels of DNA repair protein O (6)-methylguanine-DNA methyltransferase (MGMT) or deficiency/defect of DNA mismatch repair (MMR) genes is associated with TMZ resistance in some, but not all, GBM tumors. Another reason for GBM treatment failure is signal redundancy due to coactivation of several functionally linked receptor tyrosine kinases (RTKs), including anaplastic lymphoma kinase (ALK) and c-Met (hepatocyte growth factor receptor). As such, these tyrosine kinases serve as potential targets for GBM therapy. Thus, we tested two novel drugs: INC280 (Capmatinib: a highly selective c-Met receptor tyrosine kinase-RTK inhibitor) and LDK378 (Ceritinib: a highly selective anaplastic lymphoma kinase-ALK inhibitor), aiming to overcome TMZ resistance in MGMT-unmethylated GBM cells in in vitro cell culture models. Treatments were examined using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, caspase-3 assay and western blot analysis. Results obtained from our experiments demonstrated that preconditioning with INC280 and LDK378 drugs exhibit increased MMR protein expression, specifically MMR protein MLH1 (MutL Homolog 1) and MSH6 (MutS Homolog 6) and sensitized TMZ in MGMT-unmethylated GBM cells via suppression of ALK and c-Met expression. INC280 and LDK378 plus TMZ also induced apoptosis by modulating downstream signaling of PI3K/AKT/STAT3. Taken together, this data indicates that co-inhibition of ALK and c-MET can enhance growth inhibitory effects in MGMT-unmethylated cells and enhance TMZ sensitivity in-vitro, suggesting c-Met inhibitors combined with ALK-targeting provide a therapeutic benefit in MGMT-unmethylated GBM patients.
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Neoplasias Encefálicas , Glioblastoma , Preparações Farmacêuticas , Antineoplásicos Alquilantes/farmacologia , Antineoplásicos Alquilantes/uso terapêutico , Benzamidas , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/genética , Linhagem Celular Tumoral , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Resistencia a Medicamentos Antineoplásicos/genética , Glioblastoma/tratamento farmacológico , Glioblastoma/genética , Humanos , Imidazóis , Fosfatidilinositol 3-Quinases , Pirimidinas , Sulfonas , Temozolomida/farmacologia , Temozolomida/uso terapêutico , Triazinas , Proteínas Supressoras de Tumor/genéticaRESUMO
Background: Meningiomas represent â¼30% of primary central nervous system (CNS) tumors. Although advances in surgery and radiotherapy have significantly improved survival, there remains an important subset of patients whose tumors have more aggressive behavior and are refractory to conventional therapy. Recent advances in molecular genetics and epigenetics suggest that this aggressive behavior may be due to the deletion of the DNA repair and tumor suppressor gene, CHEK2, neurofibromatosis Type 2 (NF2) mutation on chromosome 22q12, and genetic abnormalities in multiple RTKs including FGFRs. Management of higher-grade meningiomas, such as anaplastic meningiomas (AM: WHO grade III), is truly challenging and there isn't an established chemotherapy option. We investigate the effect of active multi tyrosine receptor kinase inhibitor Dovitinib at stopping AM cell growth in in vitro with either frequent codeletion or mutated CHEK2 and NF2 gene.Methods: Treatment effects were assessed using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay, western blot analysis, caspases assay, and DNA fragmentation assay.Results: Treatment of CH157MN and IOMM-Lee cells with Dovitinib suppressed multiple angiokinases-mainly FGFRs, leading to suppression of downstream signaling by RAS-RAF-MAPK molecules and PI3K-AKT molecules which are involved in cell proliferation, cell survival, and tumor invasion. Furthermore, Dovitinib induced apoptosis via downregulation of survival proteins (Bcl-XL), and over-expression of apoptotic factors (Bax and caspase-3) regardless of CHEK2 and NF2 mutation status.Conclusions: This study establishes the groundwork for the development of Dovitinib as a therapeutic agent for high-grade AM with either frequent codeletion or mutated CHEK2 and NF2, an avenue with high translational potential.
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Benzimidazóis/farmacologia , Quinase do Ponto de Checagem 2/genética , Meningioma/tratamento farmacológico , Neurofibromina 2/genética , Quinolonas/farmacologia , Apoptose/efeitos dos fármacos , Caspase 3/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Meningioma/genética , Meningioma/patologia , Mutação/genética , Estadiamento de Neoplasias , Fosfatidilinositol 3-Quinases/genética , Inibidores de Proteínas Quinases/farmacologia , Proteínas Proto-Oncogênicas c-akt/genética , Receptores de Fatores de Crescimento de Fibroblastos/antagonistas & inibidores , Receptores de Fatores de Crescimento de Fibroblastos/genética , Transdução de Sinais/efeitos dos fármacos , Proteína X Associada a bcl-2/genética , Proteína bcl-X/genéticaRESUMO
PURPOSE/INTRODUCTION: Glioblastoma (GB) remains incurable despite aggressive chemotherapy, radiotherapy, and surgical interventions; immunotherapies remain experimental in clinical practice. Relevant preclinical models that can accurately predict tumor response to therapy are equally challenging. This study aimed to validate the effect of the naturally occurring agent diallyl trisulfide (DATS) in human GB in relevant pre-clinical models. METHODS: Ex vivo slice culture, in vivo cell line derived orthotopic xenograft and patient-derived orthotopic xenograft (PDX) animal models of GB were utilized to assess efficacy of treatment with DATS. RESULTS: Our results showed 72-h treatments of 25 µM DATS induced cell death in ex vivo human GB slice culture. We treated U87MG orthotopic xenograft models (U87MGOX) and patient-derived orthotopic xenograft models (PDX) with daily intraperitoneal injections of DATS for 14 days. Magnetic resonance (MR) imaging of mice treated with DATS (10 mg/kg) demonstrated reduced tumor size at 5 weeks when compared with saline-treated U87MGOX and PDX controls. Hematoxylin (H&E) staining demonstrated dose-dependent reduction in gross tumor volume with decreased proliferation and decreased angiogenesis. Western blotting showed that DATS was associated with increases in histone acetylation (Ac-Histone H3/H4) and activated caspase-3 in this novel preclinical model. Histological assessment and enzyme assays showed that even the highest dose of DATS did not negatively impact hepatic function. CONCLUSIONS: DATS may be an effective and well-tolerated therapeutic agent in preventing tumor progression and inducing apoptosis in human GB.
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Compostos Alílicos/uso terapêutico , Glioblastoma/tratamento farmacológico , Inibidores de Histona Desacetilases/uso terapêutico , Histona Desacetilases/metabolismo , Sulfetos/uso terapêutico , Compostos Alílicos/administração & dosagem , Animais , Apoptose/efeitos dos fármacos , Astrócitos/efeitos dos fármacos , Astrócitos/patologia , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Glioblastoma/enzimologia , Glioblastoma/patologia , Inibidores de Histona Desacetilases/administração & dosagem , Humanos , Masculino , Camundongos SCID , Neurônios/efeitos dos fármacos , Neurônios/patologia , Sulfetos/administração & dosagem , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
BACKGROUND: The authors report the case of a 76-year-old woman presenting with leg pain, numbness, and weakness mimicking a lumbosacral radiculopathy. CASE DESCRIPTION: Initial lumbar spine magnetic resonance imaging demonstrated mild root compression, but lumbar decompression afforded only transient symptomatic relief. Postoperative magnetic resonance imaging of the lumbosacral plexus and sciatic nerve revealed a gluteal venous varix compressing the sciatic nerve just distal to the piriformis muscle. Neurolysis and surgical resection of the offending varix resulted in resolution of her symptoms. CONCLUSIONS: Variceal compression is a rare cause of extraspinal origin of lower extremity radicular pain. It should be considered if there is lack of correlation between radiologic findings and the clinical picture or if there is a failure of response to treatment of the assumed spinal cause.
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Síndromes de Compressão Nervosa/etiologia , Ciática/etiologia , Varizes/complicações , Idoso , Descompressão Cirúrgica , Diagnóstico Diferencial , Feminino , Humanos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Síndromes de Compressão Nervosa/diagnóstico por imagem , Síndromes de Compressão Nervosa/cirurgia , Reoperação , Nervo Isquiático/diagnóstico por imagem , Ciática/diagnóstico por imagem , Ciática/cirurgia , Varizes/diagnóstico por imagem , Varizes/cirurgiaRESUMO
Polymeric nanoparticles have been extensively studied as drug delivery vehicles both in vitro and in vivo for the last two decades. In vitro methods to assess drug release profiles usually utilize degradation of nanoparticles in aqueous medium, followed by the measurement of the concentration of the released drug. This method, however, is difficult to use for drugs that are poorly water soluble. In this study, a protocol for measuring drug release kinetic using albumin solution as the medium is described. Albumin is a major blood transport protein, which mediates transport of many lipid soluble compounds including fatty acids, hormones, and bilirubin. The use of a dialysis-based system utilizing albumin dialysate solution allows hydrophobic drug release from a diverse set of drug delivery modalities is demonstrated. The method using liposomes and PLGA nanoparticles as drug carriers, and two model hydrophobic drugs, 17ß-estradiol, and dexamethasone is validated.
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Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Nanopartículas/química , Albuminas/química , Dexametasona/química , Portadores de Fármacos/uso terapêutico , Humanos , Interações Hidrofóbicas e Hidrofílicas , Cinética , Lipídeos/química , Lipossomos/química , Nanopartículas/uso terapêutico , Polímeros/química , Soluções/química , Água/químicaRESUMO
Spinal cord injury (SCI) causes loss of neurological function and, depending upon the severity of injury, may lead to paralysis. Currently, no FDA-approved pharmacotherapy is available for SCI. High-dose methylprednisolone is widely used, but this treatment is controversial. We have previously shown that low doses of estrogen reduces inflammation, attenuates cell death, and protects axon and myelin in SCI rats, but its effectiveness in recovery of function is not known. Therefore, the goal of this study was to investigate whether low doses of estrogen in post-SCI would reduce inflammation, protect cells and axons, and improve locomotor function during the chronic phase of injury. Injury (40 g.cm force) was induced at thoracic 10 in young adult male rats. Rats were treated with 10 or 100 µg 17ß-estradiol (estrogen) for 7 days following SCI and compared with vehicle-treated injury and laminectomy (sham) controls. Histology (H&E staining), immunohistofluorescence, Doppler laser technique, and Western blotting were used to monitor tissue integrity, gliosis, blood flow, angiogenesis, the expression of angiogenic factors, axonal degeneration, and locomotor function (Basso, Beattie, and Bresnahan rating) following injury. To assess the progression of recovery, rats were sacrificed at 7, 14, or 42 days post injury. A reduction in glial reactivity, attenuation of axonal and myelin damage, protection of cells, increased expression of angiogenic factors and microvessel growth, and improved locomotor function were found following estrogen treatment compared with vehicle-treated SCI rats. These results suggest that treatment with a very low dose of estrogen has significant therapeutic implications for the improvement of locomotor function in chronic SCI. Experimental studies with low dose estrogen therapy in chronic spinal cord injury (SCI) demonstrated the potential for multi-active beneficial outcomes that could ameliorate the degenerative pathways in chronic SCI as shown in (a). Furthermore, the alterations in local spinal blood flow could be significantly alleviated with low dose estrogen therapy. This therapy led to the preservation of the structural integrity of the spinal cord (b), which in turn led to the improved functional recovery as shown (c).
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Indutores da Angiogênese/administração & dosagem , Estradiol/administração & dosagem , Locomoção/efeitos dos fármacos , Recuperação de Função Fisiológica/efeitos dos fármacos , Traumatismos da Medula Espinal/tratamento farmacológico , Animais , Doença Crônica , Estrogênios/administração & dosagem , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Inflamação/patologia , Locomoção/fisiologia , Masculino , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica/fisiologia , Traumatismos da Medula Espinal/metabolismo , Traumatismos da Medula Espinal/patologiaRESUMO
Peripheral nerve involvement may be the first sign of systemic amyloid light-chain (AL) amyloidosis, a rare disease. Physical examination and electrodiagnostic testing are the mainstays of peripheral neuropathy evaluation at presentation. Sural nerve biopsy is performed in conjunction with serum and urine protein evaluation to differentiate between focal and systemic disease. Systemic disease is treated with a combination of chemotherapy, steroids, and stem cell transplantation. Isolated peripheral nerve disease is extremely rare. The authors here report the case of an 80-year-old woman who presented with progressive right upper-extremity weakness due to right radial neuropathy discovered upon electrodiagnostic testing. Magnetic resonance neurography (MRN) revealed a focal lesion within the right radial nerve. She underwent radial nerve exploration and excision of an intraneural mass consisting of amyloid on histopathology, with mass spectrometry analysis diagnostic for AL amyloidosis. Noninvasive testing and clinical history did not suggest systemic involvement. This unique case of isolated peripheral nerve AL amyloidosis in the absence of signs and symptoms of systemic disease is described, and the literature demonstrating peripheral nerve involvement in AL amyloidosis is reviewed.
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Amiloidose de Cadeia Leve de Imunoglobulina/diagnóstico , Neuropatia Radial/diagnóstico , Idoso de 80 Anos ou mais , Feminino , HumanosRESUMO
Radiation-induced necrosis (RN) is a relatively common side effect of radiation therapy for glioblastoma. However, the molecular mechanisms involved and the ways RN mechanisms differ from regulated cell death (apoptosis) are not well understood. Here, we compare the molecular mechanism of cell death (apoptosis or necrosis) of C6 glioma cells in both in vitro and in vivo (C6 othotopically allograft) models in response to low and high doses of X-ray radiation. Lower radiation doses were used to induce apoptosis, while high-dose levels were chosen to induce radiation necrosis. Our results demonstrate that active caspase-8 in this complex I induces apoptosis in response to low-dose radiation and inhibits necrosis by cleaving RIP1 and RI. When activation of caspase-8 was reduced at high doses of X-ray radiation, the RIP1/RIP3 necrosome complex II is formed. These complexes induce necrosis through the caspase-3-independent pathway mediated by calpain, cathepsin B/D, and apoptosis-inducing factor (AIF). AIF has a dual role in apoptosis and necrosis. At high doses, AIF promotes chromatinolysis and necrosis by interacting with histone H2AX. In addition, NF-κB, STAT-3, and HIF-1 play a crucial role in radiation-induced inflammatory responses embedded in a complex inflammatory network. Analysis of inflammatory markers in matched plasma and cerebrospinal fluid (CSF) isolated from in vivo specimens demonstrated the upregulation of chemokines and cytokines during the necrosis phase. Using RIP1/RIP3 kinase specific inhibitors (Nec-1, GSK'872), we also establish that the RIP1-RIP3 complex regulates programmed necrosis after either high-dose radiation or TNF-α-induced necrosis requires RIP1 and RIP3 kinases. Overall, our data shed new light on the relationship between RIP1/RIP3-mediated programmed necrosis and AIF-mediated caspase-independent programmed necrosis in glioblastoma.
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Raios gama/efeitos adversos , Glioblastoma/radioterapia , Necrose/metabolismo , Necrose/patologia , Proteínas Serina-Treonina Quinases/metabolismo , Lesões por Radiação/metabolismo , Lesões por Radiação/patologia , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Animais , Apoptose , Biomarcadores Tumorais/metabolismo , Western Blotting , Caspases , Proliferação de Células , Glioblastoma/metabolismo , Glioblastoma/patologia , Técnicas Imunoenzimáticas , Masculino , Necrose/etiologia , Lesões por Radiação/etiologia , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Spinal cord injury (SCI) is a debilitating condition with neurological deficits and loss of motor function that, depending on the severity, may lead to paralysis. The only treatment currently available is methylprednisolone, which is widely used and renders limited efficacy in SCI. Therefore, other therapeutic agents must be developed. The neuroprotective efficacy of estrogen in SCI was studied with a pre-clinical and pro-translational perspective. Acute SCI was induced in rats that were treated with low doses of estrogen (1, 5, 10, or 100 µg/kg) and compared with vehicle-treated injured rats or laminectomy control (sham) rats at 48 h post-SCI. Changes in gliosis and other pro-inflammatory responses, expression and activity of proteolytic enzymes (e.g., calpain, caspase-3), apoptosis of neurons in SCI, and cell death were monitored via Western blotting and immunohistochemistry. Negligible pro-inflammatory responses or proteolytic events and very low levels of neuronal death were found in sham rats. In contrast, vehicle-treated SCI rats showed profound pro-inflammatory responses with reactive gliosis, elevated expression and activity of calpain and caspase-3, elevated Bax:Bcl-2 ratio, and high levels of neuronal death in lesion and caudal regions of the injured spinal cord. Estrogen treatment at each dose reduced pro-inflammatory and proteolytic activities and protected neurons in the caudal penumbra in acute SCI. Estrogen treatment at 10 µg was found to be as effective as 100 µg in ameliorating the above parameters in injured animals. Results from this investigation indicated that estrogen at a low dose could be a promising therapeutic agent for treating acute SCI. Experimental studies with low dose estrogen therapy in acute spinal cord injury (SCI) demonstrated the potential for multi-active beneficial outcomes. Estrogen has been found to ameliorate several degenerative pathways following SCI. Thus, such early protective effects may even lead to functional recovery in long term injury. Studies are underway in chronic SCI in a follow up manuscript.
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Estrogênios/administração & dosagem , Estrogênios/farmacologia , Gliose/tratamento farmacológico , Neurônios/efeitos dos fármacos , Recuperação de Função Fisiológica/efeitos dos fármacos , Traumatismos da Medula Espinal/tratamento farmacológico , Animais , Morte Celular/efeitos dos fármacos , Modelos Animais de Doenças , Gliose/patologia , Masculino , Fármacos Neuroprotetores/administração & dosagem , Fármacos Neuroprotetores/farmacologia , Ratos Sprague-Dawley , Medula Espinal/fisiopatologia , Medula Espinal/cirurgia , Traumatismos da Medula Espinal/patologiaRESUMO
Glioblastoma (GB) is the most common malignant brain tumor. Drug resistance frequently develops in these tumors during chemotherapy. Therefore, predicting drug response in these patients remains a major challenge in the clinic. Thus, to improve the clinical outcome, more effective and tolerable combination treatment strategies are needed. Robust experimental evidence has shown that the main reason for failure of treatments is signal redundancy due to coactivation of several functionally linked receptor tyrosine kinases (RTKs), including anaplastic lymphoma kinase (ALK), c-Met (hepatocyte growth factor receptor), and oncogenic c-ros oncogene1 (ROS1: RTK class orphan) fusion kinase FIG (fused in GB)-ROS1. As such, these could be attractive targets for GB therapy. The study subjects consisted of 19 patients who underwent neurosurgical resection of GB tissues. Our in vitro and ex vivo models promisingly demonstrated that treatments with crizotinib (PF-02341066: dual ALK/c-Met inhibitor) and temozolomide in combination induced synergistic antitumor activity on FIG-ROS1-positive GB cells. Our results also showed that ex vivo FIG-ROS1+ slices (obtained from GB patients) when cultured were able to preserve tissue architecture, cell viability, and global gene-expression profiles for up to 14 days. Both in vitro and ex vivo studies indicated that combination blockade of FIG, p-ROS1, p-ALK, and p-Met augmented apoptosis, which mechanistically involves activation of Bim and inhibition of survivin, p-Akt, and Mcl-1 expression. However, it is important to note that we did not see any significant synergistic effect of crizotinib and temozolomide on FIG-ROS1-negative GB cells. Thus, these ex vivo culture results will have a significant impact on patient selection for clinical trials and in predicting response to crizotinib and temozolomide therapy. Further studies in different animal models of FIG-ROS1-positive GB cells are warranted to determine useful therapies for the management of human GBs.
RESUMO
Persons with spinal cord injury (SCI) are in need of effective therapeutics. Estrogen (E2), as a steroid hormone, is a highly pleiotropic agent; with anti-inflammatory, anti-apoptotic, and neurotrophic properties, it is ideal for use in treatment of patients with SCI. Safety concerns around the use of high doses of E2 have limited clinical application, however. To address these concerns, low doses of E2 (25 µg and 2.5 µg) were focally delivered to the injured spinal cord using nanoparticles. A per-acute model (6 h after injury) was used to assess nanoparticle release of E2 into damaged spinal cord tissue; in addition, E2 was evaluated as a rapid anti-inflammatory. To assess inflammation, 27-plex cytokine/chemokine arrays were conducted in plasma, cerebrospinal fluid (CSF), and spinal cord tissue. A particular focus was placed on IL-6, GRO-KC, and MCP-1 as these have been identified from CSF in human studies as potential biomarkers in SCI. S100ß, an additional proposed biomarker, was also assessed in spinal cord tissue only. Tissue concentrations of E2 were double those found in the plasma, indicating focal release. E2 showed rapid anti-inflammatory effects, significantly reducing interleukin (IL)-6, GRO-KC, MCP-1, and S100ß in one or all compartments. Numerous additional targets of rapid E2 modulation were identified including: leptin, MIP-1α, IL-4, IL-2, IL-10, IFNγ, tumor necrosis factor-α, etc. These data further elucidate the rapid anti-inflammatory effects E2 exerts in an acute rat SCI model, have identified additional targets of estrogen efficacy, and suggest nanoparticle delivered estrogen may provide a safe and efficacious treatment option in persons with acute SCI.
Assuntos
Anti-Inflamatórios/farmacologia , Estradiol/farmacologia , Inflamação/metabolismo , Traumatismos da Medula Espinal/tratamento farmacológico , Medula Espinal/metabolismo , Animais , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/uso terapêutico , Biomarcadores/metabolismo , Quimiocinas/metabolismo , Citocinas/metabolismo , Sistemas de Liberação de Medicamentos , Estradiol/administração & dosagem , Estradiol/uso terapêutico , Inflamação/sangue , Inflamação/líquido cefalorraquidiano , Masculino , Nanopartículas , Ratos , Ratos Sprague-Dawley , Subunidade beta da Proteína Ligante de Cálcio S100/metabolismo , Medula Espinal/efeitos dos fármacosRESUMO
Recurrent meningiomas constitute an uncommon but significant problem after standard (surgery and radiation) therapy failure. Current chemotherapies (hydroxyurea, RU-486, and interferon-α) are only of marginal benefit. There is an urgent need for more effective treatments for meningioma patients who have failed surgery and radiation therapy. Limonin, Tangeritin, Zerumbone, 6-Gingerol, Ganoderic Acid A, and Ganoderic Acid DM are some of the plant derivatives that have anti-tumorgenic properties and cause cell death in meningioma cells in vitro. Due to its ease of administration, long-term tolerability, and low incidence of long-term side effects, we explored its potential as a therapeutic agent against meningiomas by examining their efficacy in vitro against meningioma cells. Treatment effects were assessed using MTT assay, Western blot analysis, caspases assay, and DNA fragmentation assay. Results indicated that treatments of IOMM-Lee and CH157MN meningioma cells with Limonin, Tangeritin, Zerumbone, 6-Gingerol, Ganoderic Acid A, and Ganoderic Acid DM induced apoptosis with enhanced phosphorylation of glycogen synthase kinase 3 ß (GSK3ß) via inhibition of the Wnt5/ß-catenin pathway. These drugs did not induce apoptosis in normal human neurons. Other events in apoptosis included downregulation of tetraspanin protein (TSPAN12), survival proteins (Bcl-XL and Mcl-1), and overexpression apoptotic factors (Bax and caspase-3). These results provide preliminary strong evidence that medicinal plants containing Limonin, Tangeritin, 6-Gingerol, Zerumbone, Ganoderic Acid A, and Ganoderic Acid DM can be applied to high-grade meningiomas as a therapeutic agent, and suggests that further in vivo studies are necessary to explore its potential as a therapeutic agent against malignant meningiomas.
Assuntos
Catecóis/administração & dosagem , Álcoois Graxos/administração & dosagem , Flavonas/administração & dosagem , Ácidos Heptanoicos/administração & dosagem , Lanosterol/análogos & derivados , Limoninas/administração & dosagem , Meningioma/tratamento farmacológico , Sesquiterpenos/administração & dosagem , Triterpenos/administração & dosagem , Apoptose/efeitos dos fármacos , Catecóis/química , Linhagem Celular Tumoral , Fragmentação do DNA/efeitos dos fármacos , Álcoois Graxos/química , Flavonas/química , Quinase 3 da Glicogênio Sintase/biossíntese , Quinase 3 da Glicogênio Sintase/genética , Glicogênio Sintase Quinase 3 beta , Ácidos Heptanoicos/química , Humanos , Lanosterol/administração & dosagem , Lanosterol/química , Limoninas/química , Meningioma/genética , Meningioma/patologia , Sesquiterpenos/química , Triterpenos/química , Via de Sinalização Wnt/efeitos dos fármacosRESUMO
Glioblastoma is the most common and deadliest of malignant primary brain tumors (Grade IV astrocytoma) in adults. Current standard treatments have been improving but patient prognosis still remains unacceptably devastating. Glioblastoma recurrence is linked to epigenetic mechanisms and cellular pathways. Thus, greater knowledge of the cellular, genetic and epigenetic origin of glioblastoma is the key for advancing glioblastoma treatment. One rapidly growing field of treatment, epigenetic modifiers; histone deacetylase inhibitors (HDACis), has now shown much promise for improving patient outcomes through regulation of the acetylation states of histone proteins (a form of epigenetic modulation) and other non-histone protein targets. HDAC inhibitors have been shown, in a pre-clinical setting, to be effective anticancer agents via multiple mechanisms, by up-regulating expression of tumor suppressor genes, inhibiting oncogenes, inhibiting tumor angiogenesis and up-regulating the immune system. There are many HDAC inhibitors that are currently in pre-clinical and clinical stages of investigation for various types of cancers. This review will explain the theory of epigenetic cancer therapy, identify HDAC inhibitors that are being investigated for glioblastoma therapy, explain the mechanisms of therapeutic effects as demonstrated by pre-clinical and clinical studies and describe the current status of development of these drugs as they pertain to glioblastoma therapy.