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1.
J Neurosurg ; : 1-11, 2019 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-31491768

RESUMO

OBJECTIVE: The authors previously demonstrated that Cerebrolysin is effective for treatment of mild closed head injury (CHI) when administered 4 hours after injury. The aim of this study was to determine Cerebrolysin's effects on functional and histological outcomes in rats subjected to moderate CHI. METHODS: In this randomized, blinded, and vehicle-controlled preclinical trial, male adult Wistar rats subjected to moderate CHI received either Cerebrolysin treatment at a dose of 2.5 ml/kg (n = 13) or vehicle (saline, n = 13) intraperitoneally administered daily for 10 days, starting at 4 hours after injury. Animals were subjected to cognitive and sensorimotor functional tests at multiple time points, and they were killed 3 months after injury. The brains were processed for analyses of neuronal cell loss, amyloid precursor protein, axonal damage, and neurogenesis. RESULTS: Compared with rats treated with vehicle (saline), rats treated with Cerebrolysin had significantly increased numbers of neuroblasts and newborn mature neurons in the dentate gyrus (DG) and attenuated amyloid precursor protein accumulation and axonal damage in various brain regions, as well as decreased neuronal loss in the DG and cornu ammonis 3 (CA3) region of the hippocampus (p < 0.05). Global testing using generalized estimating equations showed a significant beneficial effect of Cerebrolysin treatment on sensorimotor functional outcomes from 1 day to 3 months after injury compared to that of saline treatment (p < 0.05). Compared with vehicle-treated rats, Cerebrolysin-treated rats showed significantly and robustly improved long-term (up to 3 months) cognitive functional recovery, as measured by social interaction, Morris water maze, novel object recognition, and odor recognition tests. In the Cerebrolysin-treated rats there were significant correlations between multiple histological outcomes and functional recovery evident 3 months after moderate CHI, as indicated by Pearson partial correlation analyses. CONCLUSIONS: The authors' findings demonstrate that Cerebrolysin treatment significantly improves long-term functional and histological outcomes in rats with moderate CHI, with functional outcomes significantly correlated with histological indices of neuroplasticity and neuroprotection. These data indicate that Cerebrolysin may be useful for the treatment of moderate CHI.

2.
J Neurosurg ; 127(3): 660-669, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27982767

RESUMO

OBJECTIVE Meningiomas express somatostatin receptor subtype 2 (SST2), which is targeted by the somatostatin analog octreotide. However, to date, using somatostatin analog therapy for the treatment of these tumors in clinical practice has been debated. This study aims to clarify the in vitro effects of octreotide on meningiomas for precise clinical applications. METHODS The effects of octreotide were analyzed in a large series of 80 meningiomas, including 31 World Health Organization (WHO) Grade II and 4 WHO Grade III tumors, using fresh primary cell cultures to study the impact on cell viability, apoptosis, and signal transduction pathways. RESULTS SST2 mRNA was detected in 100% of the tested meningiomas at levels similar to those observed in other SST2-expressing tumors, neuroendocrine tumors, or pituitary adenomas. Octreotide significantly decreased cell proliferation in 88% of meningiomas but did not induce cell death. On average, cell proliferation was more inhibited in the meningioma group expressing a high level of SST2 than in the low-SST2 group. Moreover, octreotide response was positively correlated to the level of merlin protein and inversely correlated to the level of phosphorylated p70-S6 kinase, a downstream effector of the PI3K/Akt/mammalian target of rapamycin (mTOR) pathway. Octreotide inhibited Akt phosphorylation and activated tyrosine phosphatase without impacting the extracellular regulated kinase (ERK) pathway. CONCLUSIONS Octreotide acts exclusively as an antiproliferative agent and does not promote apoptosis in meningioma in vitro. Therefore, in vivo, octreotide is likely to limit tumor growth rather than induce tumor shrinkage. A meta-analysis of the literature reveals an interest in octreotide for the treatment of WHO Grade I tumors, particularly those in the skull base for which the 6-month progression-free survival level reached 92%. Moreover, somatostatin analogs, which are well-tolerated drugs, could be of interest for use as co-targeting therapies for aggressive meningiomas.


Assuntos
Antineoplásicos Hormonais/uso terapêutico , Meningioma/tratamento farmacológico , Octreotida/uso terapêutico , Antineoplásicos Hormonais/farmacologia , Proliferação de Células/efeitos dos fármacos , Correlação de Dados , Humanos , Técnicas In Vitro , Octreotida/farmacologia , Células Tumorais Cultivadas
3.
J Neurosurg ; 127(3): 670-678, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27982773

RESUMO

OBJECTIVE Therapeutic neovascularization is a promising strategy for treating patients after an ischemic stroke; however, single-factor therapy has limitations. Stromal cell-derived factor 1 (SDF-1) and vascular endothelial growth factor (VEGF) proteins synergistically promote angiogenesis. In this study, the authors assessed the effect of combined gene therapy with VEGF165 and SDF-1 in a rat model of cerebral infarction. METHODS An adenoviral vector expressing VEGF165 and SDF-1 connected via an internal ribosome entry site was constructed (Ad- VEGF165-SDF-1). A rat model of middle cerebral artery occlusion (MCAO) was established; either Ad- VEGF165-SDF-1 or control adenovirus Ad- LacZ was stereotactically microinjected into the lateral ventricle of 80 rats 24 hours after MCAO. Coexpression and distribution of VEGF165 and SDF-1 were examined by reverse-transcription polymerase chain reaction, Western blotting, and immunofluorescence. The neurological severity score of each rat was measured on Days 3, 7, 14, 21, and 28 after MCAO. Angiogenesis and vascular remodeling were evaluated via bromodeoxyuridine and CD34 immunofluorescence labeling. Relative cerebral infarction volumes were determined by T2-weighted MRI and triphenyltetrazolium chloride staining. Cerebral blood flow, relative cerebral blood volume, and relative mean transmit time were assessed using perfusion-weighted MRI. RESULTS The Ad- VEGF165-SDF-1 vector mediated coexpression of VEGF165 and SDF-1 in multiple sites around the ischemic core, including the cortex, corpus striatum, and hippocampal granular layer. Coexpression of VEGF165 and SDF-1 improved neural function, reduced cerebral infarction volume, increased microvascular density and promoted angiogenesis in the ischemic penumbra, and improved cerebral blood flow and perfusion. CONCLUSIONS Combined VEGF165 and SDF-1 gene therapy represents a potential strategy for improving vascular remodeling and recovery of neural function after cerebral infarction.


Assuntos
Isquemia Encefálica/genética , Isquemia Encefálica/fisiopatologia , Circulação Cerebrovascular , Quimiocina CXCL12/genética , Terapia Genética/métodos , Fator A de Crescimento do Endotélio Vascular/genética , Remodelação Vascular/genética , Animais , Modelos Animais de Doenças , Masculino , Ratos , Ratos Sprague-Dawley
4.
Neurosurg Focus ; 40(5): E3, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27132524

RESUMO

Brain radiation is a fundamental tool in neurooncology to improve local tumor control, but it leads to profound and progressive impairments in cognitive function. Increased attention to quality of life in neurooncology has accelerated efforts to understand and ameliorate radiation-induced cognitive sequelae. Such progress has coincided with a new understanding of the role of CNS progenitor cell populations in normal cognition and in their potential utility for the treatment of neurological diseases. The irradiated brain exhibits a host of biochemical and cellular derangements, including loss of endogenous neurogenesis, demyelination, and ablation of endogenous oligodendrocyte progenitor cells. These changes, in combination with a state of chronic neuroinflammation, underlie impairments in memory, attention, executive function, and acquisition of motor and language skills. Animal models of radiation-induced brain injury have demonstrated a robust capacity of both neural stem cells and oligodendrocyte progenitor cells to restore cognitive function after brain irradiation, likely through a combination of cell replacement and trophic effects. Oligodendrocyte progenitor cells exhibit a remarkable capacity to migrate, integrate, and functionally remyelinate damaged white matter tracts in a variety of preclinical models. The authors here critically address the opportunities and challenges in translating regenerative cell therapies from rodents to humans. Although valiant attempts to translate neuroprotective therapies in recent decades have almost uniformly failed, the authors make the case that harnessing human radiation-induced brain injury as a scientific tool represents a unique opportunity to both successfully translate a neuroregenerative therapy and to acquire tools to facilitate future restorative therapies for human traumatic and degenerative diseases of the central nervous system.


Assuntos
Lesões Encefálicas/etiologia , Regeneração Nervosa/fisiologia , Lesões por Radiação/complicações , Animais , Encéfalo/patologia , Encéfalo/fisiopatologia , Lesões Encefálicas/complicações , Lesões Encefálicas/psicologia , Transtornos Cognitivos/etiologia , Modelos Animais de Doenças , Humanos , Oligodendroglia/fisiologia , Qualidade de Vida , Células-Tronco/fisiologia
5.
J Neurosurg ; 123(4): 1026-35, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26186026

RESUMO

OBJECT: Human lactoferrin (HLF) is a natural protein with antitumor activity. The aim of this study was to investigate the effects of HLF alone and in combination with temozolomide (TMZ), a conventional chemotherapeutic, on human glioblastoma (GBM) cells. METHODS: The authors cultured fresh human primary cell lines NMD and FN and the continuous cell line U87MG to evaluate proliferation in the presence of HLF alone at different doses (1, 10, and 100 mg/ml, and 1 mg/ml) and in combination with TMZ. In in vivo experiments they assessed tumor size reduction in CD1 nude mice carrying an orthotopic GBM xenograft and orally treated with HLF. RESULTS: Lactoferrin causes growth inhibition in the NMD and FN primary cell lines and in the U87MG continuous cell line. This inhibition seemed to be modulated by the downregulation of cyclin D1 and D4. Western blot and fluorescence-activated cell sorting analysis showed inhibition of the cell cycle in G0/G1 and G2 phases. When administered in nude mice, HLF (60 mg/kg/day) decreased tumor size about 30%, as shown in both histological analyses and high-field brain MRI. Administration of HLF with TMZ enhanced the effect of chemotherapy both in vitro and in vivo. CONCLUSIONS: This study demonstrated that HLF can inhibit GBM cell growth, suggesting that this nontoxic substance may have a role in potentiating the effect of current TMZ treatment of GBM.


Assuntos
Antineoplásicos Alquilantes/uso terapêutico , Dacarbazina/análogos & derivados , Glioblastoma/tratamento farmacológico , Lactoferrina/uso terapêutico , Animais , Antineoplásicos Alquilantes/farmacologia , Proliferação de Células/efeitos dos fármacos , Dacarbazina/farmacologia , Dacarbazina/uso terapêutico , Quimioterapia Combinada , Glioblastoma/patologia , Humanos , Lactoferrina/farmacologia , Masculino , Camundongos , Camundongos Nus , Temozolomida , Células Tumorais Cultivadas
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