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2.
Biomedicines ; 11(8)2023 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-37626642

RESUMO

(1) Background: Inducing experimental stroke leads to biphasic immune responses, where the early activation of immune functions is followed by severe immunosuppression accompanied by spleen and thymus atrophy. Nicotinamide, a water-soluble B-group vitamin, is a known neuroprotectant against brain ischemia in animal models. We examined the effect of nicotinamide on the central and peripheral immune response in experimental stroke models. (2) Methods: Nicotinamide (500 mg/kg) or saline was intravenously administered to C57BL/6 mice during reperfusion after transiently occluding the middle cerebral artery or after LPS injection. On day 3, the animals were examined for behavioral performance and were then sacrificed to assess brain infarction, blood-brain barrier (BBB) integrity, and the composition of immune cells in the brain, thymus, spleen, and blood using flow cytometry. (3) Results: Nicotinamide reduced brain infarction and microglia/macrophage activation following MCAo (p < 0.05). Similarly, in LPS-injected mice, microglia/macrophage activation was decreased upon treatment with nicotinamide (p < 0.05), suggesting a direct inhibitory effect of nicotinamide on microglia/macrophage activation. Nicotinamide decreased the infiltration of neutrophils into the brain parenchyma and ameliorated Evans blue leakage (p < 0.05), suggesting that a decreased infiltration of neutrophils could, at least partially, be the result of a more integrated BBB structure following nicotinamide treatment. Our studies also revealed that administering nicotinamide led to retarded B-cell maturation in the spleen and subsequently decreased circulating B cells in the thymus and bloodstream (p < 0.05). (4) Conclusions: Cumulatively, nicotinamide decreased brain inflammation caused by ischemia-reperfusion injury, which was mediated by a direct anti-inflammatory effect of nicotinamide and an indirect protective effect on BBB integrity. Administering nicotinamide following brain ischemia resulted in a decrease in circulating B cells. This warrants attention with respect to future clinical applications.

3.
Neurol Res ; 44(10): 870-878, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35348035

RESUMO

OBJECTIVES: Lithium has numerous neuroplastic and neuroprotective effects in patients with stroke. Here, we evaluated whether delayed and short-term lithium treatment reduces brain infarction volume and improves electrophysiological and neurobehavioral outcomes following long-term recovery after cerebral ischemia and the possible contributions of lithium-mediated mechanisms of neuroplasticity. METHODS: Male Sprague Dawley rats were subjected to right middle cerebral artery occlusion for 90 min, followed by 28 days of recovery. Lithium chloride (1 mEq/kg) or vehicle was administered via intraperitoneal infusion once per day at 24 h after reperfusion onset. Neurobehavioral outcomes and somatosensory evoked potentials (SSEPs) were examined before and 28 days after ischemia-reperfusion. Brain infarction was assessed using Nissl staining. Primary cortical neuron cultures were exposed to oxygen-glucose deprivation (OGD) and treated with 2 or 20 µM lithium for 24 or 48 h; subsequent brain-derived neurotrophic factor (BDNF), growth-associated protein-43 (GAP-43), postsynaptic density-95 (PSD-95), and synaptosomal-associated protein-25 (SNAP-25) levels were analyzed using western blotting. RESULTS: Compared to controls, lithium significantly reduced infarction volume in the ischemic brain and improved electrophysiological and neurobehavioral outcomes at 28 days post-insult. In cultured cortical neurons, BDNF, GAP-43, and PSD-95 expression were enhanced by 24- and 48-h treatment with lithium after OGD. CONCLUSION: Lithium upregulates BDNF, GAP-43, and PSD-95, which partly accounts for its improvement of neuroplasticity and provision of long-term neuroprotection in the ischemic brain.Abbreviations: BDNF: brain-derived neurotrophic factor; ECM: extracellular matrix; EDTA: ethylenediaminetetraacetic acid; GAP-43: growth-associated protein-43; GSK-3ß: glycogen synthase kinase-3ß; HBSS: Hank's balanced salt solution; LCBF: local cortical blood perfusion; LDF: laser-Doppler flowmetry; MCAO: middle cerebral artery occlusion; MMP: matrix metalloproteinase; NMDA: N-methyl-D-aspartate; NMDAR: N-methyl-D-aspartate receptor; OCT: optimal cutting temperature compound; OGD: oxygen-glucose deprivation; PSD-95: postsynaptic density-95; SDS: sodium dodecyl sulfate; SNAP-25: synaptosomal-associated protein-25; SSEP: somatosensory evoked potential.


Assuntos
Isquemia Encefálica , Proteína 4 Homóloga a Disks-Large , Proteína GAP-43 , Lítio , Fármacos Neuroprotetores , Animais , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/metabolismo , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Proteína 4 Homóloga a Disks-Large/metabolismo , Ácido Edético , Proteína GAP-43/metabolismo , Glucose , Glicogênio Sintase Quinase 3 beta/metabolismo , Infarto da Artéria Cerebral Média/metabolismo , Lítio/farmacologia , Cloreto de Lítio/farmacologia , Masculino , N-Metilaspartato , Neurônios/metabolismo , Fármacos Neuroprotetores/farmacologia , Oxigênio , Ratos , Ratos Sprague-Dawley , Receptores de N-Metil-D-Aspartato/metabolismo , Dodecilsulfato de Sódio
4.
Neurol Res ; 44(2): 128-138, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34396932

RESUMO

OBJECTIVES: Lithium exerts a broad neuroprotective effect on the brain. This study examined whether lithium exerts therapeutic effects on stroke by restoring neural connections at the ischemic core of cortices post brain insult. METHODS: We treated rats with lithium or vehicle (saline) every 24 h for the first 72 h, starting at the beginning of reperfusion after inducing middle cerebral artery occlusion (MCAO) in rats. Somatosensory evoked potential (SSEP) recording and behavioral testing were employed to evaluate the beneficial effects of lithium treatment. To examine the effects of lithium-induced neuroplasticity, we evaluated the dendritic morphology in cortex pyramidal cells and the primary neuronal cell culture that underwent brain insults and oxygen and glucose deprivation (OGD), respectively. RESULTS: The results demonstrated that rats subjected to MCAO had prolonged N1 latency and a decreased N1/P1 amplitude at the ipsilateral cortex. Four doses of lithium reduced the brain infarction volume and enhanced the SSEP amplitude. The results of neurobehavioral tests demonstrated that lithium treatment improved sensory function, as demonstrated by improved 28-point clinical scale scores. In vitro study results showed that lithium treatment increased the dendritic lengths and branches of cultured neurons and reversed the suppressive effects of OGD. The in vivo study results indicated that lithium treatment increased cortical spine density in various layers and resulted in the development of the dendritic structure in the contralateral hemisphere. CONCLUSION: Our study confirmed that neuroplasticity in cortical neurons is crucial for lithium-induced brain function 50 recovery after brain ischemia.


Assuntos
Córtex Cerebral/efeitos dos fármacos , Potenciais Somatossensoriais Evocados/efeitos dos fármacos , Infarto da Artéria Cerebral Média/complicações , AVC Isquêmico/complicações , Compostos de Lítio/farmacologia , Plasticidade Neuronal/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Células Piramidais/efeitos dos fármacos , Traumatismo por Reperfusão/etiologia , Traumatismo por Reperfusão/prevenção & controle , Animais , Células Cultivadas , Modelos Animais de Doenças , Compostos de Lítio/administração & dosagem , Fármacos Neuroprotetores/administração & dosagem , Ratos
5.
Transl Cancer Res ; 10(9): 3906-3920, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35116690

RESUMO

BACKGROUND: Temozolomide (TMZ) has been widely used to treat glioblastoma multiforme (GBM). However, many mechanisms are known to quickly adapt GBM cells to chemotherapy with TMZ, leading to drug resistance and expansion of tumor cell populations. METHODS: We subjected human glioblastoma cell lines and an animal model of glioblastoma xenografts with TMZ-based adjuvant treatments to evaluate the synergistic effect of cinnamophilin (CINN), a free radical scavenger. RESULTS: Our results showed that the combined treatment of CINN and TMZ potentiated the anticancer effect and apoptotic cell death in glioma cell lines and enhanced antitumor action in glioma xenografts. TMZ induced reactive oxygen species (ROS) burst and elevated G2 arrest in glioma cells. The CINN-suppressed ROS burst in TMZ-treated glioma cells might be associated with increased apoptosis, as indicated by the upregulation of TUNEL-positive glioma cells. CINN-pretreated glioma cells exhibited increased cyclin B expression and reduced phosphorylation of Cdk1, suggesting reduced G2 arrest in the combined treatment group. Moreover, CINN lowered the protein level of LC3, a hallmark of autophagy, in TMZ-treated cells. CONCLUSIONS: These findings suggest that CINN may restore TMZ toxicity in glioma cancer by suppressing the ROS/G2 arrest pathway.

6.
J Neurol Surg Rep ; 81(1): e20-e27, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32257765

RESUMO

Objective Atlantoaxial fixation is technically demanding and challenging, especially in cases with anatomical abnormality. The purpose of this study is to report the effectiveness of the three-dimensional (3D)-customized guiding template for placement of C1 and C2 screws in cases with abnormalities. Method Two patients with anatomical abnormality and one without were included. The preoperative computed tomography (CT) image was analyzed using our software. The entry point, trajectory, and depth of the screws were designed based on these images. Templates with screw guiding cylinders and cervical spine model were created. In operation, guiding templates were applied directly to the laminae. Drilling, tapping, and screwing were performed through the cylinders. To evaluate the accuracy, deviation of the screw axis from the preplanned trajectory was measured on postoperative CT. A classification system was taking to evaluate the pedicle screw insertion. Results In complex cases, one of C2 screws has grade 2 deviation, and two has grade 1. There was no deviation in screws of C1. All patients achieved symptoms free after 6 months follow-up. Conclusion Although 3D-printed template for atlantoaxial fixation still has limitation in complex cases, it has been proved usefulness and makes the most difficult and dangerous spinal posterior fixation easy to achieve.

7.
Neurol Res ; 38(7): 625-33, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27264544

RESUMO

OBJECTIVES: Flow cytometry was applied to predict the biological parameters of tumor behavior based on the DNA content distribution of tumors. We used flow cytometry to determine the number of cell cycles for the characterization of intracranial gliomas and its possible prognostic role. METHODS: Flow cytometric analysis of the DNA content was performed for 37 fresh operative glioma specimens. The expression of Ki-67 in glioma specimens was detected using immunohistochemistry staining. The check points of G2/M-phase fractions, cyclin B, and pCdk1 (Y15) were analyzed using Western immunoblotting. RESULTS: Compared to low-grade (grade I/II) gliomas, significant differences in the Ki-67, cyclin B, G2/M-phase, and S+G2/M-phase expressions were found in high-grade (grade III/IV) gliomas. Furthermore, receiver operating characteristic (ROC) analysis indicated optimal cutoff points for the G2/M-phase and S+G2/M-phase fractions of 13.47 and 17.26%, respectively, which can be used to differentiate cases with low- and high-grade gliomas. Additionally, both G2/M-phase and S+G2/M-phase fractions had significant association with the expression of Ki-67 in the gliomas. The gliomas were classified by the DNA content. We found that patients with high-grade glioma had worse survival rate than patients with low-grade glioma. Meanwhile, ROC curve analysis gave cutoffs for G2/M-phase of 9.4% and for S+G2/M-phase fractions of 15.04% as best predicting survival. The patients with glioma had poor survival when the levels of G2/M-phase and S+G2/M-phase were more than 9.4 and 15.04%, respectively. In contrast, no significant association between the DNA content of glioma patients and their age, tumor recurrence, and tumor size was found. DISCUSSION: Our results indicate that flow cytometry analysis for G2/M-phase and S+G2/M-phase fractions can be used for tumor grading for rapidly differentiating low- from high-grade gliomas.


Assuntos
Neoplasias Encefálicas/patologia , Citometria de Fluxo/métodos , Glioma/patologia , Gradação de Tumores/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Neoplasias Encefálicas/metabolismo , Ciclo Celular/fisiologia , Ciclina B/metabolismo , DNA/metabolismo , Feminino , Glioma/complicações , Humanos , Antígeno Ki-67/metabolismo , Masculino , Pessoa de Meia-Idade , Curva ROC , Estudos Retrospectivos
8.
J Stroke Cerebrovasc Dis ; 24(9): e261-3, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26119279

RESUMO

Pontine hemorrhage is a life-threatening emergency which may result in high mortality and devastating disability. Trigeminal denervation is usually caused by neoplasms and trauma but rarely occurs after pontine hemorrhage. Herein, we present a patient with delayed trigeminal motor denervation who presents with progressive atrophy of the right temporalis and masseter muscles 1 year after pontine hemorrhage. Details of the pathogenesis and correlation between clinical, electrophysiological, and radiological findings are addressed.


Assuntos
Denervação , Hemorragias Intracranianas/complicações , Ponte/patologia , Doenças do Nervo Trigêmeo/etiologia , Idoso , Feminino , Humanos , Imageamento por Ressonância Magnética , Tomógrafos Computadorizados
9.
Cytometry B Clin Cytom ; 88(5): 312-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25408130

RESUMO

BACKGROUND: Meningiomas have classically been considered to include benign and atypical/anaplastic tumors. Despite the availability of clinical and pathologic parameters for prognostic prediction prognosis, the behavior of each meningioma may be difficult to predict. Here, we used DNA flow-cytometric studies to predict biological tumor behaviors of intracranial meningiomas. METHODS: The specimens were obtained from fresh tumoral tissues of 43 microsurgically resected meningiomas as approved by the institutional review board. The presence of G2/M-phase and S+G2/M-phase fractions were analyzed and correlated with the proliferation index of Ki-67 and the World Health Organization grading. The check point of G2/M-phase fraction, cyclin B, and pCdk1 (Y15), were analyzed by Western blotting. RESULTS: Our results showed that there were significant differences in Ki-67, G2/M-phase, S+G2/M-phase fractions, and cyclin B between benign and atypical/anaplastic meningiomas. The optimal cutoff point of G2/M-phase and S+G2/M-phase fractions were 5.12 and 7.52%, respectively, and this can be used to discriminate those cases with benign or atypical/anaplastic meningiomas. Besides, both the G2/M-phase and S+G2/M-phase fractions were correlated well with Ki-67 and the histopathological features such as focal necrosis, infiltration of dura mater and mitotic activity. In addition, the occurrence of tumor recurrence and patient age were correlated to the G2/M-phase and S+G2/M-phase fractions, respectively. The G2/M-phase and S+G2/M-phase fractions, however, did not correlate well with histologic invasion to adjacent bone, sinus, or brain tissues. CONCLUSIONS: The use of flow cytometry facilitates additional information for G2/M-phase and S+G2/M-phase fractions represent tumoral grading and risk of recurrence in patients with meningiomas.


Assuntos
Biomarcadores Tumorais/genética , DNA de Neoplasias/genética , Citometria de Fluxo , Pontos de Checagem da Fase G2 do Ciclo Celular , Neoplasias Meníngeas/genética , Meningioma/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/análise , Western Blotting , Proteína Quinase CDC2 , Proliferação de Células , Ciclina B/análise , Quinases Ciclina-Dependentes/análise , Feminino , Humanos , Imuno-Histoquímica , Antígeno Ki-67/análise , Masculino , Neoplasias Meníngeas/química , Neoplasias Meníngeas/patologia , Neoplasias Meníngeas/cirurgia , Meningioma/química , Meningioma/patologia , Meningioma/cirurgia , Pessoa de Meia-Idade , Gradação de Tumores , Recidiva Local de Neoplasia , Valor Preditivo dos Testes , Estudos Prospectivos , Fatores de Risco , Resultado do Tratamento
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