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1.
Dysphagia ; 37(5): 1201-1206, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-34762204

RESUMO

Aspiration after stroke is associated with pneumonia and mortality. In this study, we investigated brain structural connectivity associated with aspiration after unilateral supratentorial stroke. Patients on oral feeding after stroke were divided into liquid aspiration (22 patients) and normal (18 patients) groups based on videofluoroscopic swallowing studies. Voxel-based lesion-symptom mapping and voxel-wise group comparison of fractional anisotropy, mode of anisotropy, and mean diffusivity maps were conducted. Voxel-based lesion-symptom mapping revealed no significant lesion differences between groups. The aspiration group showed significantly increased fractional anisotropy and mode of anisotropy in the anterior limb and the genu of the internal capsule in the right hemisphere. In contrast, the normal group showed significantly increased mean diffusivity, mainly in the superior longitudinal fasciculus in the right hemisphere (P < 0.05). Degeneration of the internal capsule in the right hemisphere was found to affect aspiration after stroke.


Assuntos
Acidente Vascular Cerebral , Anisotropia , Encéfalo , Imagem de Difusão por Ressonância Magnética , Humanos , Rede Nervosa , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/patologia
2.
Neuroradiology ; 63(6): 905-912, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33037503

RESUMO

PURPOSE: To compare the image quality of brain computed tomography (CT) images reconstructed with deep learning-based image reconstruction (DLIR) and adaptive statistical iterative reconstruction-Veo (ASIR-V). METHODS: Sixty-two patients underwent routine noncontrast brain CT scans and datasets were reconstructed with 30% ASIR-V and DLIR with three selectable reconstruction strength levels (low, medium, high). Objective parameters including CT attenuation, noise, noise reduction rate, artifact index of the posterior cranial fossa, and contrast-to-noise ratio (CNR) were measured at the levels of the centrum semiovale and basal ganglia. Subjective parameters including gray matter-white matter differentiation, sharpness, and overall diagnostic quality were also assessed and compared with the interobserver agreement. RESULTS: There was a gradual reduction in the image noise and artifact index of the posterior cranial fossa as the strength levels of DLIR increased (all P < 0.001) compared with that of ASIR-V. CNR in both the centrum semiovale and basal ganglia levels also improved from the low to high strength levels of DLIR compared with that of ASIR-V (all P < 0.001). DLIR images with medium and high strength levels demonstrated the best subjective image quality scores among the reconstruction datasets. There was moderate to good interobserver agreement for the subjective image quality assessments with ASIR-V and DLIR. CONCLUSION: On routine brain CT scans, optimized protocols with DLIR allowed significant reduction of noise and artifacts with improved subjective image quality compared with ASIR-V.


Assuntos
Aprendizado Profundo , Algoritmos , Encéfalo/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador , Doses de Radiação , Interpretação de Imagem Radiográfica Assistida por Computador , Tomografia Computadorizada por Raios X
3.
Acta Radiol ; 62(6): 791-798, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32664747

RESUMO

BACKGROUND: Susceptibility-weighted imaging (SWI) is occasionally performed with intravenous gadolinium (Gd). It was reported that SWI can be performed after Gd injection without information loss or signal change. PURPOSE: To investigate the diagnostic value of contrast-enhanced SWI (CE-SWI) in the assessment of intracranial brain neoplasm. MATERIAL AND METHODS: After obtaining the approval of the local ethics committee, 35 brain neoplasm patients (24 with metastasis and 11 with glioblastoma multiforme [GBM]) were enrolled. In order to investigate the value of using CE-SWI, two neuroradiologists performed an evaluation of the frequency of the intratumoral susceptibility signals (ITSS) in SWI and CE-SWI with visual assessment using 5-grade scales. We evaluated the visibility of the tumor margins and the internal architecture of tumors on T1-weighted imaging (T1WI), contrast-enhanced T1 (CE-T1), SWI, and CE-SWI. RESULTS: The contrast-enhanced scans (CE-T1 and CE-SWI) showed statistically significant higher scores compared to non-enhanced scans (T1WI and SWI) for the analysis of the tumor margin in GBM and metastasis (P < 0.05, Wilcoxon signed rank test). Statistically significant higher scores are noted in GBMs compared to metastases in the visibility of the internal architecture of tumors on CE-SWI and the visibility of the tumor margin on CE-T1 (P < 0.05, Mann-Whitney test). CONCLUSION: Based on our results, SWI can be performed after gadolinium injection without information loss or signal change. CE-SWI is useful in evaluating intracranial neoplasm due to its ability to simultaneously demonstrate both ITSS that are not visible with conventional magnetic resonance sequences and contrast enhancement.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Meios de Contraste , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Meglumina , Compostos Organometálicos , Idoso , Idoso de 80 Anos ou mais , Encéfalo/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes
4.
Int J Mol Sci ; 22(18)2021 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-34576008

RESUMO

GBM is a high-grade cancer that originates from glial cells and has a poor prognosis. Although a combination of surgery, radiotherapy, and chemotherapy is prescribed to patients, GBM is highly resistant to therapies, and surviving cells show increased aggressiveness. In this study, we investigated the molecular mechanism underlying GBM progression after radiotherapy by establishing a GBM orthotopic xenograft mouse model. Based on transcriptomic analysis, we found that the expression of BEX1 and BEX4 was upregulated in GBM cells surviving radiotherapy. We also found that upregulated expression of BEX1 and BEX4 was involved in the formation of the filamentous cytoskeleton and altered mechanotransduction, which resulted in the activation of the YAP/TAZ signaling pathway. BEX1- and BEX4-mediated YAP/TAZ activation enhanced the tumor formation, growth, and radioresistance of GBM cells. Additionally, latrunculin B inhibited GBM progression after radiotherapy by suppressing actin polymerization in an orthotopic xenograft mouse model. Taken together, we suggest the involvement of cytoskeleton formation in radiation-induced GBM progression and latrunculin B as a GBM radiosensitizer.


Assuntos
Actinas/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Glioblastoma/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Proteínas Oncogênicas/metabolismo , Transdução de Sinais , Fatores de Transcrição/metabolismo , Actinas/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Linhagem Celular Tumoral , Glioblastoma/genética , Glioblastoma/patologia , Xenoenxertos , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteínas Associadas aos Microtúbulos/genética , Transplante de Neoplasias , Proteínas do Tecido Nervoso/genética , Proteínas Oncogênicas/genética , Fatores de Transcrição/genética , Proteínas de Sinalização YAP
5.
Int J Mol Sci ; 22(6)2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33804169

RESUMO

Glioblastoma multiforme (GBM) is a malignant primary brain tumor with poor patient prognosis. Although the standard treatment of GBM is surgery followed by chemotherapy and radiotherapy, often a small portion of surviving tumor cells acquire therapeutic resistance and become more aggressive. Recently, altered kinase expression and activity have been shown to determine metabolic flux in tumor cells and metabolic reprogramming has emerged as a tumor progression regulatory mechanism. Here we investigated novel kinase-mediated metabolic alterations that lead to acquired GBM radioresistance and malignancy. We utilized transcriptomic analyses within a radioresistant GBM orthotopic xenograft mouse model that overexpresses the dual specificity tyrosine-phosphorylation-regulated kinase 3 (DYRK3). We find that within GBM cells, radiation exposure induces DYRK3 expression and DYRK3 regulates mammalian target of rapamycin complex 1 (mTORC1) activity through phosphorylation of proline-rich AKT1 substrate 1 (PRAS40). We also find that DYRK3 knockdown inhibits dynamin-related protein 1 (DRP1)-mediated mitochondrial fission, leading to increased oxidative phosphorylation (OXPHOS) and reduced glycolysis. Importantly, enforced DYRK3 downregulation following irradiation significantly impaired GBM cell migration and invasion. Collectively, we suggest DYRK3 suppression may be a novel strategy for preventing GBM malignancy through regulating mitochondrial metabolism.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Dinaminas/genética , Glioblastoma/radioterapia , Proteínas Serina-Treonina Quinases/genética , Proteínas Tirosina Quinases/genética , Animais , Linhagem Celular Tumoral , Proliferação de Células/genética , Proliferação de Células/efeitos da radiação , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Glioblastoma/genética , Glioblastoma/patologia , Humanos , Camundongos , Mitocôndrias/genética , Mitocôndrias/patologia , Mitocôndrias/efeitos da radiação , Fosforilação Oxidativa/efeitos da radiação , Proteínas Proto-Oncogênicas c-akt/genética , Tolerância a Radiação/genética , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Int J Mol Sci ; 22(10)2021 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-34065991

RESUMO

Although there are many patients with brain tumors worldwide, there are numerous difficulties in overcoming brain tumors. Among brain tumors, glioblastoma, with a 5-year survival rate of 5.1%, is the most malignant. In addition to surgical operations, chemotherapy and radiotherapy are generally performed, but the patients have very limited options. Temozolomide is the most commonly prescribed drug for patients with glioblastoma. However, it is difficult to completely remove the tumor with this drug alone. Therefore, it is necessary to discuss the potential of anticancer drugs, other than temozolomide, against glioblastomas. Since the discovery of cisplatin, platinum-based drugs have become one of the leading chemotherapeutic drugs. Although many studies have reported the efficacy of platinum-based anticancer drugs against various carcinomas, studies on their effectiveness against brain tumors are insufficient. In this review, we elucidated the anticancer effects and advantages of platinum-based drugs used in brain tumors. In addition, the cases and limitations of the clinical application of platinum-based drugs are summarized. As a solution to overcome these obstacles, we emphasized the potential of a novel approach to increase the effectiveness of platinum-based drugs.


Assuntos
Antineoplásicos/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Glioblastoma/tratamento farmacológico , Compostos de Platina/uso terapêutico , Antineoplásicos/farmacologia , Neoplasias Encefálicas/metabolismo , Ensaios Clínicos como Assunto , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Glioblastoma/metabolismo , Humanos , Compostos de Platina/farmacologia , Análise de Sobrevida , Resultado do Tratamento
7.
Stroke ; 50(10): 2956-2959, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31545695

RESUMO

Background and Purpose- Brain areas associated with functional improvement differ between acute and chronic phases after stroke. This study investigated brain areas associated with language function, according to time after stroke. Methods- Patients with aphasia after stroke were divided into subacute (≤3 months after stroke, 17 patients) and chronic groups (>12 months after stroke, 23 patients). Voxel-wise linear regression analyses in each group were conducted by using fractional anisotropy mapping in diffusion tensor images as a dependent variable, while scores of spontaneous speech, comprehension, repetition, and naming were used as independent variables. Results- Structural connectivity in the left dorsal pathway (eg, superior temporal gyrus, inferior parietal lobule, and superior longitudinal fasciculus) was positively associated with spontaneous speech, repetition, and naming, whereas structural connectivity in the corona radiata, internal capsule, and corpus callosum of the right hemisphere was negatively associated with language function in the subacute phase. Comprehension was associated with the left superior temporal gyrus and the right corona radiata in the subacute phase and the right corpus callosum in the chronic phase (PFWE<0.05). Conclusions- More lateralized language function related to the dorsal pathway was influenced in the bilateral brain areas in the subacute phase but not in the chronic phase. Less lateralized language function related to the ventral pathway was influenced in the bilateral brain areas during both subacute and chronic phases after stroke.


Assuntos
Afasia/fisiopatologia , Encéfalo/fisiopatologia , Acidente Vascular Cerebral/fisiopatologia , Idoso , Afasia/etiologia , Doença Crônica , Imagem de Tensor de Difusão , Feminino , Humanos , Masculino , Estudos Retrospectivos , Acidente Vascular Cerebral/complicações
8.
Int J Mol Sci ; 20(8)2019 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-31027222

RESUMO

Activation of epithelial-mesenchymal transition (EMT) is thought to be an essential step for cancer metastasis. Tumor cells undergo EMT in response to a diverse range of extra- and intracellular stimulants. Recently, it was reported that metabolic shifts control EMT progression and induce tumor aggressiveness. In this review, we summarize the involvement of altered glucose, lipid, and amino acid metabolic enzyme expression and the underlying molecular mechanisms in EMT induction in tumor cells. Moreover, we propose that metabolic regulation through gene-specific or pharmacological inhibition may suppress EMT and this treatment strategy may be applied to prevent tumor progression and improve anti-tumor therapeutic efficacy. This review presents evidence for the importance of metabolic changes in tumor progression and emphasizes the need for further studies to better understand tumor metabolism.


Assuntos
Transição Epitelial-Mesenquimal , Metabolismo , Aminoácidos/metabolismo , Animais , Glucose/metabolismo , Humanos , Metabolismo dos Lipídeos , Neoplasias/metabolismo , Neoplasias/terapia
9.
Cell Physiol Biochem ; 47(6): 2233-2249, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29975946

RESUMO

BACKGROUND/AIMS: Non-alcoholic fatty liver disease (NAFLD) is an emerging metabolic disease. Although it leads to severe hepatic diseases including steatohepatitis, cirrhosis, and hepatic cancer, little is known about therapy to prevent and cure hepatic steatosis, the first step of NAFLD. We conducted this investigation to unveil the mechanism of hepatic steatosis. METHODS: We established a novel chronic NAFLD mouse model through whole body irradiation and verified the model through histological and biochemical analysis. To find molecular mechanism for hepatic steatosis, we analyzed hepatic transcriptomic profiles in this model and selected target molecule. To induce the expression of lactotransferrin (Ltf) and regulate the NAFLD, growth hormone (GH) and coumestrol was introduced to hepatocyte and mice. The universal effect of coumestrol was confirmed by administration of coumestrol to NAFLD mouse model induced by high-fructose, high-fat, and MCD diet. RESULTS: It was observed that decreased hepatic Ltf expression led to excessive hepatic lipid accumulation in NAFLD mouse. Furthermore, we found that GH was decreased in irradiated mice and functioned as an upstream regulator of Ltf expression. It was observed that GH could stimulate Ltf expression and prevent uptake of dietary lipids in hepatocytes, leading to rescue of NAFLD. Finally, we suggested that coumestrol, a kind of isoflavonoid, could be used as an inducer of hepatic Ltf expression through cooperation with the GH signaling pathway both in vitro and in vivo. CONCLUSIONS: Hepatic Ltf prevents hepatic steatosis through inhibition of dietary lipid uptake in radiation-induced NAFLD mouse model. We also suggest coumestrol as a drug candidate for prevention of NAFLD.


Assuntos
Hepatócitos/metabolismo , Lactoferrina/biossíntese , Hepatopatia Gordurosa não Alcoólica/metabolismo , Transdução de Sinais , Animais , Linhagem Celular , Doença Crônica , Gorduras na Dieta/metabolismo , Gorduras na Dieta/farmacologia , Hepatócitos/patologia , Masculino , Camundongos , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/patologia , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Lesões Experimentais por Radiação/genética , Lesões Experimentais por Radiação/metabolismo , Lesões Experimentais por Radiação/patologia , Lesões Experimentais por Radiação/prevenção & controle
10.
Int J Mol Sci ; 19(9)2018 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-30227629

RESUMO

Hyperthermia is a cancer treatment where tumor tissue is heated to around 40 °C. Hyperthermia shows both cancer cell cytotoxicity and immune response stimulation via immune cell activation. Immunogenic responses encompass the innate and adaptive immune systems, involving the activation of macrophages, natural killer cells, dendritic cells, and T cells. Moreover, hyperthermia is commonly used in combination with different treatment modalities, such as radiotherapy and chemotherapy, for better clinical outcomes. In this review, we will focus on hyperthermia-induced immunogenic effects and molecular events to improve radiotherapy efficacy. The beneficial potential of integrating radiotherapy with hyperthermia is also discussed.


Assuntos
Hipertermia Induzida/métodos , Neoplasias/terapia , Radioterapia/métodos , Animais , Terapia Combinada/métodos , Humanos , Imunidade Celular , Imunidade Inata , Imunoterapia/métodos , Neoplasias/imunologia , Neoplasias/patologia , Neoplasias/radioterapia
11.
Biomater Res ; 28: 0010, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38464469

RESUMO

The increasing prevalence of endocrine-disrupting chemicals (EDCs) in our environment is a growing concern, with numerous studies highlighting their adverse effects on the human endocrine system. Among the EDCs, estrogenic endocrine-disrupting chemicals (eEDCs) are exogenous compounds that perturb estrogenic hormone function by interfering with estrogen receptor (ER) homo (α/α, ß/ß) or hetero (α/ß) dimerization. To date, a comprehensive screening approach for eEDCs affecting all ER dimer forms in live cells is lacking. Here, we developed ER dimerization-detecting biosensors (ERDDBs), based on bioluminescence resonance energy transfer, for dimerization detection and rapid eEDC identification. To enhance the performance of these biosensors, we determined optimal donor and acceptor locations using computational analysis. Additionally, employing HaloTag as the acceptor and incorporating the P2A peptide as a linker yielded the highest sensitivity among the prototypes. We also established stable cell lines to screen potential ER dimerization inducers among estrogen analogs (EAs). The EAs were categorized through cross-comparison of ER dimer responses, utilizing EC values derived from a standard curve established with 17ß-estradiol. We successfully classified 26 of 72 EAs, identifying which ER dimerization types they induce. Overall, our study underscores the effectiveness of the optimized ERDDB for detecting ER dimerization and its applicability in screening and identifying eEDCs.

12.
Elife ; 122023 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-38131292

RESUMO

Cranial irradiation is used for prophylactic brain radiotherapy as well as the treatment of primary brain tumors. Despite its high efficiency, it often induces unexpected side effects, including cognitive dysfunction. Herein, we observed that mice exposed to cranial irradiation exhibited cognitive dysfunction, including altered spontaneous behavior, decreased spatial memory, and reduced novel object recognition. Analysis of the actin cytoskeleton revealed that ionizing radiation (IR) disrupted the filamentous/globular actin (F/G-actin) ratio and downregulated the actin turnover signaling pathway p21-activated kinase 3 (PAK3)-LIM kinase 1 (LIMK1)-cofilin. Furthermore, we found that IR could upregulate microRNA-206-3 p (miR-206-3 p) targeting PAK3. As the inhibition of miR-206-3 p through antagonist (antagomiR), IR-induced disruption of PAK3 signaling is restored. In addition, intranasal administration of antagomiR-206-3 p recovered IR-induced cognitive impairment in mice. Our results suggest that cranial irradiation-induced cognitive impairment could be ameliorated by regulating PAK3 through antagomiR-206-3 p, thereby affording a promising strategy for protecting cognitive function during cranial irradiation, and promoting quality of life in patients with radiation therapy.


Assuntos
Disfunção Cognitiva , MicroRNAs , Animais , Humanos , Camundongos , Actinas/metabolismo , Antagomirs , Disfunção Cognitiva/genética , Irradiação Craniana/efeitos adversos , Regulação para Baixo , Quinases Lim/metabolismo , MicroRNAs/genética , Quinases Ativadas por p21/genética , Quinases Ativadas por p21/metabolismo , Qualidade de Vida
13.
Biochim Biophys Acta Rev Cancer ; 1878(6): 188988, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37726064

RESUMO

The Warburg effect is a phenomenon in which cancer cells rely primarily on glycolysis rather than oxidative phosphorylation, even in the presence of oxygen. Although evidence of its involvement in cell proliferation has been discovered, the advantages of the Warburg effect in cancer cell survival under treatment have not been fully elucidated. In recent years, the metabolic characteristics of radioresistant cancer cells have been evaluated, enabling an extension of the original concept of the Warburg effect. In this review, we focused on the role of the Warburg effect in redox homeostasis and DNA damage repair, two critical factors contributing to radioresistance. In addition, we highlighted the metabolic involvement in the radioresistance of cancer stem cells, which is the root cause of tumor recurrence. Finally, we summarized radiosensitizing drugs that target the Warburg effect. Insights into the molecular mechanisms underlying the Warburg effect and radioresistance can provide valuable information for developing strategies to enhance the efficacy of radiotherapy and provide future directions for successful cancer therapy.


Assuntos
Neoplasias , Radiossensibilizantes , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/genética , Neoplasias/radioterapia , Glicólise , Fosforilação Oxidativa , Oxigênio/metabolismo
14.
Cell Rep Med ; 4(1): 100880, 2023 01 17.
Artigo em Inglês | MEDLINE | ID: mdl-36603576

RESUMO

Glioblastoma (GBM) currently has a dismal prognosis. GBM cells that survive radiotherapy contribute to tumor progression and recurrence with metabolic advantages. Here, we show that diacylglycerol kinase B (DGKB), a regulator of the intracellular concentration of diacylglycerol (DAG), is significantly downregulated in radioresistant GBM cells. The downregulation of DGKB increases DAG accumulation and decreases fatty acid oxidation, contributing to radioresistance by reducing mitochondrial lipotoxicity. Diacylglycerol acyltransferase 1 (DGAT1), which catalyzes the formation of triglycerides from DAG, is increased after ionizing radiation. Genetic inhibition of DGAT1 using short hairpin RNA (shRNA) or microRNA-3918 (miR-3918) mimic suppresses radioresistance. We discover that cladribine, a clinical drug, activates DGKB, inhibits DGAT1, and sensitizes GBM cells to radiotherapy in vitro and in vivo. Together, our study demonstrates that DGKB downregulation and DGAT1 upregulation confer radioresistance by reducing mitochondrial lipotoxicity and suggests DGKB and DGAT1 as therapeutic targets to overcome GBM radioresistance.


Assuntos
Diacilglicerol Quinase , Glioblastoma , Humanos , Diacilglicerol Quinase/genética , Diacilglicerol Quinase/metabolismo , Diacilglicerol O-Aciltransferase/genética , Diacilglicerol O-Aciltransferase/metabolismo , Glioblastoma/genética , Glioblastoma/radioterapia , Lipídeos/toxicidade , Triglicerídeos/metabolismo , Regulação para Cima
15.
Int J Biol Macromol ; 253(Pt 8): 127511, 2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-37866557

RESUMO

Glioblastoma Multiforme (GBM) is a malignant primary brain tumor. Radiotherapy, one of the standard treatments for GBM patients, could induce GBM radioresistance via rewiring cellular metabolism. However, the precise mechanism attributing to GBM radioresistance or targeting strategies to overcome GBM radioresistance are lacking. Here, we demonstrate that SLC25A22, a mitochondrial bi-directional glutamate transporter, is upregulated and showed uni-directionality from mitochondria to cytosol in radioresistant GBM cells, resulting in accumulating cytosolic glutamate. However, mitochondrial glutaminolysis-mediated TCA cycle metabolites and OCR are maintained constantly. The accumulated cytosolic glutamate enhances the glutathione (GSH) production and proline synthesis in radioresistant GBM cells. Increased GSH protects cells against ionizing radiation (IR)-induced reactive oxygen species (ROS) whereas increased proline, a rate-limiting substrate for collagen biosynthesis, induces extracellular matrix (ECM) remodeling, leading to GBM invasive phenotypes. Finally, we discover that genetic inhibition of SLC25A22 using miR-184 mimic decreases GBM radioresistance and aggressiveness both in vitro and in vivo. Collectively, our study suggests that SLC25A22 upregulation confers GBM radioresistance by rewiring glutamate metabolism, and SLC25A22 could be a significant therapeutic target to overcome GBM radioresistance.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Humanos , Glioblastoma/genética , Glioblastoma/radioterapia , Glioblastoma/metabolismo , Ácido Glutâmico , Tolerância a Radiação/genética , Linhagem Celular Tumoral , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/metabolismo , Mitocôndrias/metabolismo , Prolina , Proteínas de Transporte da Membrana Mitocondrial
16.
J Pers Med ; 12(1)2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-35055396

RESUMO

This study investigated the changes in the structural connectivity of the bilateral hemispheres over time following a middle cerebral artery infarction. Eighteen patients in the subacute group and nine patients in the chronic group with mild upper extremity motor impairment (Fugl-Meyer motor assessment score for the upper limb > 43) following middle cerebral artery infarction were retrospectively evaluated in this study. All the patients underwent T1-weighted and diffusion tensor imaging. Tract-based statistical analyses of fractional anisotropy were used to compare the changes in the bilateral structural connectivity with those of age-matched normal controls. The corticospinal tract pathway of the affected hemisphere, corpus callosum, and corona radiata of the unaffected hemisphere had decreased structural connectivity in the subacute group, while the motor association area and anterior corpus callosum in the bilateral frontal lobes had increased structural connectivity in the chronic group. The bilateral hemispheres were influenced even in patients with mild motor impairment following middle cerebral artery infarction, and the structural connectivity of the bilateral hemispheres changed according to the time following the stroke.

17.
J Clin Med ; 11(11)2022 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-35683416

RESUMO

(1) Background: The impairment of language function after a stroke is common. It is unclear how the brain reorganizes for language function after cerebral infarction. The aim of this observational study is to investigate the association of structural integrity and functional neural activity with language function in aphasic patients with middle cerebral artery infarction. (2) Methods: Magnetic resonance images and scores from the Western Aphasia Battery on 20 patients were retrieved from medical records. A Voxel-wise linear regression analysis was performed using fractional anisotropy maps or the fractional amplitude of low-frequency fluctuation maps as dependent variables and scores of oral language function as independent variables while controlling for age and time elapsed after stroke. (3) Results: Spontaneous speech was positively associated with fractional anisotropy in the left dorsal stream and the right posterior corpus callosum and with the fractional amplitude of the low-frequency fluctuation of cranial nuclei in the pontomedullary junction. Comprehension was positively associated with the left ventral stream. Naming was positively associated with the left ventral stream and the bilateral occipitofrontal fasciculus, as well as with the fractional amplitude of low-frequency fluctuation of the supramarginal gyrus in the left hemisphere. (4) Conclusions: The dorsal and ventral streams are important for articulation and meaning after the reorganization of neural circuits following stroke. Subdomains of oral language function with a visual component are dependent on the visual association areas located in the right hemisphere.

18.
Neurobiol Stress ; 16: 100423, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35028340

RESUMO

Selective serotonin reuptake inhibitors (SSRIs) are effective first line therapies for treating depression, but are plagued by undesirable side effects and are not effective in all patients. Because SSRIs effectively deplete the neuronal releasable serotonin (5-HT) pool, gaining a deeper understanding of intracellular mechanisms regulating 5-HT pools can help us understand the shortcomings of SSRIs and develop more effective therapies. In this study, we found that BAIAP3 (brain-specific angiogenesis inhibitor 1-associated protein 3) is significantly downregulated in two mouse models of depression (the IR- and CUMS-induced depressive mouse models). In BAIAP3 downregulated models (in vitro and in vivo), we discovered that trafficking of dense core vesicle (DCV), organelles that store, transport and release cargo via exocytosis, was reduced. Accordingly, 5-HT exocytosis and levels in the synapse were lowered, causing defective post-synaptic neurotransmission. In a screen of natural products, we identified eucalyptol, the active components of Eucalyptus, as uniquely capable of increasing neuronal Baiap3 expression and elevate synaptic 5-HT levels. Moreover, eucalyptol treatment relieved depressive behavioral symptoms and restored serotonin levels in mice. Mechanistically, eucalyptol restores Baiap3 expression by reducing inhibitory microRNAs (miR-329, miR-362). These findings illuminate how Baiap3 depletion propagates neurotransmission dysfunction and point to eucalyptol as a novel agent for restoring serotonin exocytosis, suggesting potential for developing eucalyptol as a therapy for treating depression.

19.
Cells ; 11(19)2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-36231065

RESUMO

Cancer cachexia is a muscle-wasting syndrome that leads to a severely compromised quality of life and increased mortality. A strong association between cachexia and poor prognosis has been demonstrated in intractable cancers, including glioblastoma (GBM). In the present study, it was demonstrated that ionizing radiation (IR), the first-line treatment for GBM, causes cancer cachexia by increasing the exosomal release of plasminogen activator inhibitor-1 (PAI-1) from glioblastoma cells. Exosomal PAI-1 delivered to the skeletal muscle is directly penetrated in the muscles and phosphorylates STAT3 to intensify muscle atrophy by activating muscle RING-finger protein-1 (MuRF1) and muscle atrophy F-box (Atrogin1); furthermore, it hampers muscle protein synthesis by inhibiting mTOR signaling. Additionally, pharmacological inhibition of PAI-1 by TM5441 inhibited muscle atrophy and rescued muscle protein synthesis, thereby providing survival benefits in a GBM orthotopic xenograft mouse model. In summary, our data delineated the role of PAI-1 in the induction of GBM cachexia associated with radiotherapy-treated GBM. Our data also indicated that targeting PAI-1 could serve as an attractive strategy for the management of GBM following radiotherapy, which would lead to a considerable improvement in the quality of life of GBM patients undergoing radiotherapy.


Assuntos
Caquexia , Glioblastoma , Animais , Caquexia/etiologia , Caquexia/metabolismo , Glioblastoma/complicações , Glioblastoma/radioterapia , Humanos , Camundongos , Proteínas Musculares/metabolismo , Atrofia Muscular/metabolismo , Inibidor 1 de Ativador de Plasminogênio , Qualidade de Vida , Radiação Ionizante , Serina-Treonina Quinases TOR
20.
Biomedicines ; 10(6)2022 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-35740330

RESUMO

Glioblastoma (GBM) is the most malignant primary brain tumor. The current standard approach in GBM is surgery, followed by treatment with radiation and temozolomide (TMZ); however, GBM is highly resistant to current therapies, and the standard of care has not been revised over the last two decades, indicating an unmet need for new therapies. GBM stem cells (GSCs) are a major cause of chemoresistance due to their ability to confer heterogeneity and tumorigenic capacity. To improve patient outcomes and survival, it is necessary to understand the properties and mechanisms underlying GSC chemoresistance. In this review, we describe the current knowledge on various resistance mechanisms of GBM to therapeutic agents, with a special focus on TMZ, and summarize the recent findings on the intrinsic and extrinsic mechanisms of chemoresistance in GSCs. We also discuss novel therapeutic strategies, including molecular targeting, autophagy inhibition, oncolytic viral therapy, drug repositioning, and targeting of GSC niches, to eliminate GSCs, from basic research findings to ongoing clinical trials. Although the development of effective therapies for GBM is still challenging, this review provides a better understanding of GSCs and offers future directions for successful GBM therapy.

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