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1.
J Pineal Res ; 76(1): e12925, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37986632

RESUMO

Stroke is the leading cause of death and disability worldwide. Novel and effective therapies for ischemic stroke are urgently needed. Here, we report that melatonin receptor 1A (MT1) agonist ramelteon is a neuroprotective drug candidate as demonstrated by comprehensive experimental models of ischemic stroke, including a middle cerebral artery occlusion (MCAO) mouse model of cerebral ischemia in vivo, organotypic hippocampal slice cultures ex vivo, and cultured neurons in vitro; the neuroprotective effects of ramelteon are diminished in MT1-knockout (KO) mice and MT1-KO cultured neurons. For the first time, we report that the MT1 receptor is significantly depleted in the brain of MCAO mice, and ramelteon treatment significantly recovers the brain MT1 losses in MCAO mice, which is further explained by the Connectivity Map L1000 bioinformatic analysis that shows gene-expression signatures of MCAO mice are negatively connected to melatonin receptor agonist like Ramelteon. We demonstrate that ramelteon improves the cerebral blood flow signals in ischemic stroke that is potentially mediated, at least, partly by mechanisms of activating endothelial nitric oxide synthase. Our results also show that the neuroprotection of ramelteon counteracts reactive oxygen species-induced oxidative stress and activates the nuclear factor erythroid 2-related factor 2/heme oxygenase-1 pathway. Ramelteon inhibits the mitochondrial and autophagic death pathways in MCAO mice and cultured neurons, consistent with gene set enrichment analysis from a bioinformatics perspective angle. Our data suggest that Ramelteon is a potential neuroprotective drug candidate, and MT1 is the neuroprotective target for ischemic stroke, which provides new insights into stroke therapy. MT1-KO mice and cultured neurons may provide animal and cellular models of accelerated ischemic damage and neuronal cell death.


Assuntos
Isquemia Encefálica , Indenos , AVC Isquêmico , Melatonina , Fármacos Neuroprotetores , Acidente Vascular Cerebral , Animais , Camundongos , AVC Isquêmico/tratamento farmacológico , Receptor MT1 de Melatonina/agonistas , Neuroproteção , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Transdução de Sinais , Melatonina/farmacologia , Isquemia Encefálica/tratamento farmacológico , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/genética , Camundongos Knockout , Infarto da Artéria Cerebral Média/tratamento farmacológico , Infarto da Artéria Cerebral Média/metabolismo
2.
J Nanobiotechnology ; 20(1): 39, 2022 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-35062946

RESUMO

BACKGROUND: Glioblastoma (GBM) is the most common and fatal primary tumor in the central nervous system (CNS). Due to the existence of blood-brain barrier (BBB), most therapeutics cannot efficiently reach tumors in the brain, and as a result, they are unable to be used for effective GBM treatment. Accumulating evidence shows that delivery of therapeutics in form of nanoparticles (NPs) may allow crossing the BBB for effective GBM treatment. METHODS: Betulinic acid NPs (BA NPs) were synthesized by the standard emulsion approach and characterized by electron microscopy and dynamic light scattering analysis. The resulting NPs were characterized for their anti-tumor effects by cell viability assay, EdU-DNA synthesis assay, cell cycle assay, mitochondrial membrane potential, and PI-FITC apoptosis assay. Further mechanistic studies were carried out through Western Blot and immunostaining analyses. Finally, we evaluated BA NPs in vivo for their pharmacokinetics and antitumor effects in intracranial xenograft GBM mouse models. RESULTS: BA NPs were successfully prepared and formed into rod shape. BA NPs could significantly suppress glioma cell proliferation, induce apoptosis, and arrest the cell cycle in the G0/G1 phase in vitro. Furthermore, BA NPs downregulated the Akt/NFκB-p65 signaling pathway in a concentration dependent manner. We found that the observed anti-tumor effect of BA NPs was dependent on the function of CB1/CB2 receptors. Moreover, in the intracranial GBM xenograft mouse models, BA NPs could effectively cross the BBB and greatly prolong the survival time of the mice. CONCLUSIONS: We successfully synthesized BA NPs, which could cross the BBB and demonstrated a strong anti-tumor effect. Therefore, BA NPs may potentially be used for effective treatment of GBM.


Assuntos
Antineoplásicos Fitogênicos , Neoplasias Encefálicas/metabolismo , Glioblastoma/metabolismo , Nanopartículas/química , Triterpenos Pentacíclicos , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Humanos , Camundongos , Triterpenos Pentacíclicos/química , Triterpenos Pentacíclicos/farmacologia , Receptores de Canabinoides/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto , Ácido Betulínico
3.
Nanomedicine ; 44: 102581, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35811067

RESUMO

Glioblastoma multiforme (GBM) is the intracranial malignancy with the highest rates of morbidity and mortality. Chemotherapy is often ineffective against GBM due to the presence of the blood-brain barrier (BBB); however, the application of nanotechnology is expected to overcome this limitation. Poly(lactic-co-glycolic acid) (PLGA) is a degradable and nontoxic functional polymer with good biocompatibility that is widely used in the pharmaceutical industry. Previous studies have shown that the ability of PLGA nanoparticles (NPs) to penetrate the BBB is largely determined by their size; however, determination of the optimal PLGA NP size requires further research. Here, we report a tandutinib-based prodrug (proTan), which responds to the GBM microenvironment, that was combined with NPs to overcome the BBB. AMD3100-PLGA NPs loaded with proTan inhibited tumor growth and effectively prolonged the survival of tumor-bearing mice.


Assuntos
Glioblastoma , Nanopartículas , Pró-Fármacos , Animais , Linhagem Celular Tumoral , Portadores de Fármacos/uso terapêutico , Sistemas de Liberação de Medicamentos , Esterases/uso terapêutico , Glioblastoma/tratamento farmacológico , Glioblastoma/patologia , Ácido Láctico , Camundongos , Ácido Poliglicólico , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Pró-Fármacos/farmacologia , Pró-Fármacos/uso terapêutico , Microambiente Tumoral
4.
Nano Lett ; 21(19): 8111-8118, 2021 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-34597054

RESUMO

Despite being promising, the clinical application of magnetic hyperthermia for brain cancer treatment is limited by the requirement of highly invasive intracranial injections. To overcome this limitation, here we report the development of gallic acid-coated magnetic nanoclovers (GA-MNCs), which allow not only for noninvasive delivery of magnetic hyperthermia but also for targeted delivery of systemic chemotherapy to brain tumors. GA-MNCs are composed of clover-shaped MNCs in the core, which can induce magnetic heat in high efficiency, and polymerized GA on the shell, which enables tumor vessel-targeting. We demonstrate that intravenous administration of GA-MNCs following alternating magnetic field exposure effectively inhibited brain cancer development and preferentially disrupted tumor vasculature, making it possible to efficiently deliver systemic chemotherapy for further improved efficacy. Due to the noninvasive nature and high efficiency in killing tumor cells and enhancing systemic drug delivery, GA-MNCs have the potential to be translated for improved treatment of brain cancer.


Assuntos
Neoplasias Encefálicas , Hipertermia Induzida , Nanopartículas de Magnetita , Neoplasias Encefálicas/tratamento farmacológico , Linhagem Celular Tumoral , Humanos , Hipertermia , Fenômenos Magnéticos
5.
Nano Lett ; 20(6): 4084-4094, 2020 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-32379462

RESUMO

Nanoparticle (NP)-based cancer immunotherapy has been extensively explored. However, the efficacy of existing strategies is often limited by the lack of effective tumor-specific antigens or the inability to present costimulatory signal or both. Here, we report a novel approach to overcoming these limitations through surface coating with dendritic-tumor fusion cell membranes, which present whole repertories of tumor-associated antigens in the presence of costimulatory molecules. Because antigen-presenting and costimulatory molecules are displayed on their surface, these NPs can efficiently penetrate immune organs and activate T cells. We show that these NPs can be utilized to prevent tumor development and regress established tumors, including tumors in the brain. We demonstrate that encapsulation of immune adjuvants further improves their efficacy. Due to their significant efficacy, the whole tumor antigen-presenting costimulatory NPs have the potential to be translated into clinical applications for treatment of various cancers.


Assuntos
Imunoterapia , Nanopartículas , Neoplasias , Antígenos de Neoplasias , Biomimética , Células Dendríticas , Humanos , Neoplasias/terapia
6.
Cancer ; 126(5): 1016-1030, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31769872

RESUMO

BACKGROUND: PLEKHA5 has previously been identified as a novel molecule implicated in melanoma brain metastasis, a disease that continues to portend a poor prognosis. The aim of this study was to further investigate the functional role of PLEKHA5 in disseminated melanoma. METHODS: The impact of PLEKHA5 on proliferation and tumor growth was examined in vitro and in melanoma xenograft models, including brain-tropic melanomas (melanomas tending to disseminate to the brain). In vitro loss- and gain-of-function studies were used to explore the underlying mechanisms of PLEKHA5-mediated tumor growth and the crosstalk between PLEKHA5 and PI3K/AKT/mTOR or MAPK/ERK signaling. The clinical relevance of PLEKHA5 dysregulation was further investigated in a cohort of matched cranial and extracranial melanoma metastases. RESULTS: PLEKHA5 stable knockdown negatively regulated cell proliferation by inhibiting the G1 -to-S cell cycle transition, which coincided with upregulation of the cell cycle regulator PDCD4. Conversely, ectopic PLEKHA5 expression exhibited the inverse effect. PLEKHA5 knockdown significantly inhibited tumor growth, whereas its overexpression upregulated the growth of tumors, which was induced by cranial and subcutaneous inoculation of cells in nude mice. PLEKHA5 modulation affected PDCD4 protein stability and was coupled with changes in PI3K/AKT/mTOR pathway signaling. High PDCD4 expression in cerebral specimens was associated with better overall survival. CONCLUSIONS: This study further supports the role of PLEKHA5 as a regulator of melanoma growth at distant sites, including the brain. Furthermore, the results highlight the significance of PDCD4 dysregulation in disseminated melanoma and implicate PDCD4 as a possible causal link between PLEKHA5 and cell proliferation and growth.


Assuntos
Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas/secundário , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Melanoma/patologia , Adulto , Idoso , Animais , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Biomarcadores Tumorais/genética , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Feminino , Seguimentos , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/genética , Masculino , Melanoma/genética , Melanoma/metabolismo , Camundongos , Camundongos Nus , Pessoa de Meia-Idade , Fosfatidilinositol 3-Quinases/genética , Fosfatidilinositol 3-Quinases/metabolismo , Prognóstico , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto , Adulto Jovem
7.
Adv Funct Mater ; 30(14)2020 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-32440263

RESUMO

Breast cancer brain metastases (BCBMs) represent a major cause of morbidity and mortality among patients with breast cancer. Chemotherapy, which is widely used to treat tumors outside of the brain, is often ineffective on BCBMs due to its inability to efficiently cross the blood-brain barrier (BBB). Although the BBB is partially disrupted in tumor lesions, it remains intact enough to prevent most therapeutics from entering the brain. Here, we report a nanotechnology approach that can overcome the BBB through synthesis of lexiscan-loaded, AMD3100-conjugated, shrinkable NPs, or LANPs. LANPs respond to neutrophil elastase-enriched tumor microenvironment by shrinking in size and disrupt the BBB in tumors through lexiscan-mediated modulation. LANPs recognize tumor cells through the interaction between AMD3100 and CXCR4, which are expressed in metastatic tumor cells. We demonstrate that the integration of tumor responsiveness, tumor targeting, and BBB penetration enables LANPs to penetrate metastatic lesions in the brain with high efficiency, and, when doxorubicin was encapsulated, LANPs effectively inhibited tumor growth and prolonged the survival of tumor-bearing mice. Due to their high efficiency in penetrating the BBB for BCBMs treatment, LANPs have the potential to be translated into clinical applications for improved treatment of patients with BCBMs.

8.
Mol Pharm ; 17(4): 1343-1351, 2020 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-32150416

RESUMO

Breast cancer is the most common type of cancer in women. About 12% of all women in the United States will be diagnosed with breast cancer over their lifetimes. At the same time, incidences of brain metastases (BMs) are increasing and represent an emerging health threat. However, there is no effective chemotherapy for breast cancer brain metastases (BCBMs), which is largely due to lack of efficient delivery of antitumor drugs or drug combinations to the brain. In this study, oleanolic acid (OA), a natural pentacyclic triterpenoid compound with excellent antitumor activity, was found to form nanoparticles (NPs) and efficiently penetrate the brain for BCBMs treatment. On the basis of these findings, we developed a synergistic combinatorial chemotherapeutic regimen by formulating paclitaxel (PTX) into OA NPs and demonstrated that the resulting PTX-OA NPs effectively inhibited primary breast cancer and BCBMs in mouse xenografts. Collectively, this study introduces a new direction to treat primary breast cancer and BCBMs through noninvasive combination chemotherapy.


Assuntos
Antineoplásicos/farmacologia , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias da Mama/tratamento farmacológico , Nanopartículas/química , Ácido Oleanólico/farmacologia , Paclitaxel/farmacologia , Animais , Encéfalo/efeitos dos fármacos , Linhagem Celular Tumoral , Sinergismo Farmacológico , Feminino , Humanos , Camundongos , Camundongos Nus
9.
Small ; 15(35): e1902011, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31290245

RESUMO

Cell membrane coating has recently emerged as a promising biomimetic approach to engineering nanoparticles (NPs) for targeted drug delivery. However, simple cell membrane coating may not meet the need for efficient drug delivery to the brain. Here, a novel molecular engineering strategy to modify the surface of NPs with a cell membrane coating for enhanced brain penetration is reported. By using poly(lactic-co-glycolic) acid NPs as a model, it is shown that delivery of NPs to the ischemic brain is enhanced through surface coating with the membrane of neural stem cells (NSCs), and the delivery efficiency can be further increased using membrane isolated from NSCs engineered for overexpression of CXCR4. It is found that this enhancement is mediated by the chemotactic interaction of CXCR4 with SDF-1, which is enriched in the ischemic microenvironment. It is demonstrated that the resulting CXCR4-overexpressing membrane-coated NPs, termed CMNPs, significantly augment the efficacy of glyburide, an anti-edema agent, for stroke treatment. The study suggests a new approach to improving drug delivery to the ischemic brain and establishes a novel formulation of glyburide that can be potentially translated into clinical applications to improve management of human patients with stroke.


Assuntos
Quimiotaxia , Sistemas de Liberação de Medicamentos , Glibureto/administração & dosagem , Nanopartículas , Células-Tronco Neurais/metabolismo , Acidente Vascular Cerebral/tratamento farmacológico , Animais , Membrana Celular/metabolismo , Quimiocina CXCL12/metabolismo , Glibureto/uso terapêutico , Humanos , Camundongos , Receptores CXCR4/metabolismo
10.
J Cell Biochem ; 119(10): 8481-8489, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29987852

RESUMO

Long noncoding RNA focally amplified lncRNA on chromosome 1 (FAL1) plays an important role in the development of several human malignancy entities. However, the expression and function of FAL1 in the carcinogenesis and development of osteosarcoma remain unknown. In this study, we detected the FAL1 levels in human osteosarcoma tissues and cell lines by quantitative real-time polymerase chain reaction and investigated its role in osteosarcoma using in vitro assays. Our results showed that FAL1 expression was significantly upregulated in human osteosarcoma tissues and cell lines compared with their normal controls. FAL1 expression level was positively correlated with the distance metastasis (P = .008) and tumor stage ( P = .013). Higher expression of FAL1 conferred a significantly poorer survival, as determined by the Kaplan-Meier method with the log-rank test. Multivariate Cox proportional hazards analysis revealed that FAL1 was probably an independent risk of overall survival. Additionally, the serum FAL1 expression level was associated with osteosarcoma status in patients. Receiver operating characteristic curve analysis demonstrated that FAL1 expression was different between patients with osteosarcoma and healthy cohorts (area under the curve, 0.839; P < .001). Furthermore, knockdown of FAL1 by small interfering RNA significantly inhibited cell proliferation via inducing G2/M arrest in osteosarcoma cells. Depletion of FAL1 also suppressed osteosarcoma cell migration and invasion, which might be mediated by inhibiting the epithelial-mesenchymal transition (EMT) program. Taken together, our study showed that lncRNA FAL1 exhibits an important pro-oncogenic effect on osteosarcoma progression by targeting EMT, which may serve as a potential therapeutic target for osteosarcoma.


Assuntos
Neoplasias Ósseas/sangue , Neoplasias Ósseas/genética , Osteossarcoma/sangue , Osteossarcoma/genética , RNA Longo não Codificante/sangue , RNA Longo não Codificante/genética , Adulto , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/genética , Neoplasias Ósseas/mortalidade , Neoplasias Ósseas/patologia , Pontos de Checagem do Ciclo Celular , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Progressão da Doença , Transição Epitelial-Mesenquimal , Feminino , Técnicas de Silenciamento de Genes , Inativação Gênica , Humanos , Estimativa de Kaplan-Meier , Masculino , Análise Multivariada , Invasividade Neoplásica , Osteossarcoma/mortalidade , Osteossarcoma/patologia , Prognóstico , Modelos de Riscos Proporcionais , Taxa de Sobrevida , Transfecção , Regulação para Cima/genética
11.
Biochem Biophys Res Commun ; 499(2): 112-119, 2018 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-29470982

RESUMO

Traumatic brain injury (TBI) is a leading cause of disability and mortality in young adults worldwide. The pathophysiology is not fully understood. Programmed necrosis (necroptosis) is a newly identified mechanism of cell death combining features of both apoptosis and necrosis. Receptor-interacting protein 3 (RIP3) plays an important role in programmed necrosis. However, the effect of RIP3-related pathway in TBI is little to be known. We attempted to explore the significance of RIP3 in regulating TBI in vivo. Significantly, TBI induced over-expression of RIP3 in the hippocampus of mice, as well as RIP1 and phosphorylated mixed lineage kinase domain-like protein (MLKL). Mice after TBI exhibited cognitive dysfunction and activation of glia cells, which were significantly attenuated by RIP3-knockout (KO). Moreover, inflammation and oxidative stress in hippocampus were markedly induced by TBI in wild type (WT) mice. Of note, the reduction of pro-inflammatory cytokines and oxidants was observed in RIP3-deficient mice, which was linked to the blockage of NLR pyrin domain containing 3 (NLRP3)/apoptosis-associated speck-like protein containing a CARD (ASC)/Caspase-1 and kelch-like ECH-associated protein 1 (Keap 1) pathways. Further, TBI induced hippocampus apoptosis, evidenced by the increase of cleaved Caspase-8/-3 and poly (ADP)-ribose polymerase (PARP) in WT mice, whereas being decreased by RIP3-knockout. In addition, RIP3 knockout led to phosphorylation of AMP-activated protein kinase α (AMPKα) in hippocampus of mice after TBI. And of note, the in vitro findings indicated that RIP3-ablation attenuated oxidative stress, inflammation and apoptosis in astrocytes, which was dependent on AMPKα activation. Together, suppressing RIP3 might be served as a therapeutic target against brain injury through inhibiting inflammation, oxidative stress and apoptosis.


Assuntos
Adenilato Quinase/metabolismo , Apoptose , Lesões Encefálicas Traumáticas/enzimologia , Lesões Encefálicas Traumáticas/prevenção & controle , Inflamação/patologia , Estresse Oxidativo , Proteína Serina-Treonina Quinases de Interação com Receptores/deficiência , Transdução de Sinais , Animais , Astrócitos/enzimologia , Astrócitos/patologia , Lesões Encefálicas Traumáticas/patologia , Lesões Encefálicas Traumáticas/fisiopatologia , Cognição , Constrição Patológica , Deleção de Genes , Hipocampo/patologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo
12.
Cell Mol Biol Lett ; 22: 30, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29270202

RESUMO

BACKGROUND: Gliomas are commonly malignant tumors that arise in the human central nervous system and have a low overall five-year survival rate. Previous studies reported that several members of Rab GTPase family are involved in the development of glioma, and abnormal expression of Rab small GTPases is known to cause aberrant tumor cell behavior. In this study, we characterized the roles of Rab21 (Rab GTPase 21), a member of Rab GTPase family, in glioma cells. METHODS: The study involved downregulation of Rab21 in two glioma cell lines (T98G and U87) through transfection with specific-siRNA. Experiments using the MTT assay, cell cycle analysis, apoptosis assay, real-time PCR and western blot were performed to establish the expression levels of related genes. RESULTS: The results show that downregulation of Rab21 can significantly inhibit cell growth and remarkably induce cell apoptosis in T98G and U87 cell lines. Silencing Rab21 resulted in significantly increased expression of apoptosis-related proteins (caspase7, Bim and Bax) in glioma cells. CONCLUSIONS: We inferred that Rab21 silencing can induce apoptosis and inhibit proliferation in human glioma cells, indicating that Rab21 might act as an oncogene and serve as a novel target for glioma therapy.


Assuntos
Apoptose , Neoplasias Encefálicas/patologia , Técnicas de Silenciamento de Genes , Glioma/patologia , Proteínas rab de Ligação ao GTP/genética , Neoplasias Encefálicas/metabolismo , Pontos de Checagem do Ciclo Celular , Linhagem Celular Tumoral , Proliferação de Células , Fase G1 , Regulação Neoplásica da Expressão Gênica , Inativação Gênica , Glioma/metabolismo , Humanos , RNA Interferente Pequeno/metabolismo , Fase de Repouso do Ciclo Celular , Transfecção , Proteínas rab de Ligação ao GTP/metabolismo
13.
J Huazhong Univ Sci Technolog Med Sci ; 35(2): 259-264, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25877362

RESUMO

Although 5-aminolevulinic acid (5-ALA)-mediated photodynamic therapy (PDT) has been demonstrated to be a novel and effective therapeutic modality for some human malignancies, its effect and mechanism on glioma are still controversial. Previous studies have reported that 5-ALA-PDT induced necrosis of C6 rat glioma cells in vitro. The aim of this study was to further investigate the effect and mechanism of 5-ALA-PDT on C6 gliomas implanted in rats in vivo. Twenty-four rats bearing similar size of subcutaneously implanted C6 rat glioma were randomly divided into 3 groups: receiving 5-ALA-PDT (group A), laser irradiation (group B), and mock procedures but without any treatment (group C), respectively. The growth, histology, microvessel density (MVD), and apoptosis of the grafts in each group were determined after the treatments. As compared with groups B and C, the volume of tumor grafts was significantly reduced (P<0.05), MVD was significantly decreased (P<0.001), and the cellular necrosis was obviously increased in group A. There was no significant difference in apoptosis among the three groups. The in vivo studies confirmed that 5-ALA-PDT may be an effective treatment for gliomas by inhibiting the tumor growth. The mechanism underlying may involve increasing the cellular necrosis but not inducing the cellular apoptosis, which may result from the destruction of the tumor microvessels.


Assuntos
Ácido Aminolevulínico/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Glioma/tratamento farmacológico , Microvasos/efeitos dos fármacos , Fotoquimioterapia , Fármacos Fotossensibilizantes/uso terapêutico , Ácido Aminolevulínico/farmacologia , Animais , Neoplasias Encefálicas/irrigação sanguínea , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Glioma/irrigação sanguínea , Glioma/patologia , Fármacos Fotossensibilizantes/farmacologia , Ratos , Ratos Wistar , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Front Genet ; 15: 1380696, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38841721

RESUMO

Studies have indicated that the preservation of joint health and the facilitation of damage recovery are predominantly contingent upon the joint's microenvironment, including cell-cell interactions, the extracellular matrix's composition, and the existence of local growth factors. Mesenchymal stem cells (MSCs), which possess the capacity to self-renew and specialize in many directions, respond to cues from the microenvironment, and aid in the regeneration of bone and cartilage, are crucial to this process. Changes in the microenvironment (such as an increase in inflammatory mediators or the breakdown of the extracellular matrix) in the pathological context of arthritis might interfere with stem cell activation and reduce their ability to regenerate. This paper investigates the potential role of joint microenvironmental variables in promoting or inhibiting the development of arthritis by influencing stem cells' ability to regenerate. The present status of research on stem cell activity in the joint microenvironment is also outlined, and potential directions for developing new treatments for arthritis that make use of these intervention techniques to boost stem cell regenerative potential through altering the intra-articular environment are also investigated. This review's objectives are to investigate these processes, offer fresh perspectives, and offer a solid scientific foundation for the creation of arthritic treatment plans in the future.

15.
Front Cell Infect Microbiol ; 14: 1380136, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38633744

RESUMO

Osteoporosis, arthritis, and fractures are examples of orthopedic illnesses that not only significantly impair patients' quality of life but also complicate and raise the expense of therapy. It has been discovered in recent years that the pathophysiology of orthopedic disorders is significantly influenced by the microbiota. By employing machine learning and deep learning techniques to conduct a thorough analysis of the disease-causing microbiome, we can enhance our comprehension of the pathophysiology of many illnesses and expedite the creation of novel treatment approaches. Today's science is undergoing a revolution because to the introduction of machine learning and deep learning technologies, and the field of biomedical research is no exception. The genesis, course, and management of orthopedic disorders are significantly influenced by pathogenic microbes. Orthopedic infection diagnosis and treatment are made more difficult by the lengthy and imprecise nature of traditional microbial detection and characterization techniques. These cutting-edge analytical techniques are offering previously unheard-of insights into the intricate relationships between orthopedic health and pathogenic microbes, opening up previously unimaginable possibilities for illness diagnosis, treatment, and prevention. The goal of biomedical research has always been to improve diagnostic and treatment methods while also gaining a deeper knowledge of the processes behind the onset and development of disease. Although traditional biomedical research methodologies have demonstrated certain limits throughout time, they nevertheless rely heavily on experimental data and expertise. This is the area in which deep learning and machine learning approaches excel. The advancements in machine learning (ML) and deep learning (DL) methodologies have enabled us to examine vast quantities of data and unveil intricate connections between microorganisms and orthopedic disorders. The importance of ML and DL in detecting, categorizing, and forecasting harmful microorganisms in orthopedic infectious illnesses is reviewed in this work.


Assuntos
Aprendizado Profundo , Microbiota , Doenças Musculoesqueléticas , Humanos , Qualidade de Vida , Aprendizado de Máquina
16.
J Neurosurg ; : 1-11, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38608304

RESUMO

OBJECTIVE: Circulating tumor cell (CTC) detection is a promising noninvasive technique that can be used to diagnose cancer, monitor progression, and predict prognosis. In this study, the authors aimed to investigate the clinical utility of CTCs in the management of diffuse glioma. METHODS: Sixty-three patients with newly diagnosed diffuse glioma were included in this multicenter clinical cohort. The authors used a platform based on isolation by size of epithelial tumor cells (ISET) to detect and analyze CTCs and circulating tumor microemboli (CTMs) in the peripheral blood of patients both before and after surgery. Least absolute shrinkage and selector operation (LASSO) and Cox regression analyses were used to verify whether CTCs and CTMs are independent prognostic factors for diffuse glioma. RESULTS: CTC levels were closely related to the degree of malignancy, WHO grade, and pathological subtypes. Receiver operating characteristic curve analysis revealed that a high CTC level was a predictor for glioblastoma. The results also showed that CTMs originate from the parental tumor rather than from the circulation and are an independent prognostic factor for diffuse glioma. The postoperative CTC level is related to the peripheral immune system and patient survival. Cox regression analysis showed that postoperative CTC levels and CTM status are independent prognostic factors for diffuse glioma, and CTC- and CTM-based survival models had high accuracy in internal validation. CONCLUSIONS: The authors revealed a correlation between CTCs and clinical characteristics and demonstrated that CTCs and CTMs are independent predictors for the diagnosis and prognosis of diffuse glioma. Their CTC- and CTM-based survival models can enable clinicians to evaluate patients' response to surgery as well as their outcomes.

17.
J Exp Med ; 221(4)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38442272

RESUMO

Meningeal lymphatic vessels (MLVs) promote tissue clearance and immune surveillance in the central nervous system (CNS). Vascular endothelial growth factor-C (VEGF-C) regulates MLV development and maintenance and has therapeutic potential for treating neurological disorders. Herein, we investigated the effects of VEGF-C overexpression on brain fluid drainage and ischemic stroke outcomes in mice. Intracerebrospinal administration of an adeno-associated virus expressing mouse full-length VEGF-C (AAV-mVEGF-C) increased CSF drainage to the deep cervical lymph nodes (dCLNs) by enhancing lymphatic growth and upregulated neuroprotective signaling pathways identified by single nuclei RNA sequencing of brain cells. In a mouse model of ischemic stroke, AAV-mVEGF-C pretreatment reduced stroke injury and ameliorated motor performances in the subacute stage, associated with mitigated microglia-mediated inflammation and increased BDNF signaling in brain cells. Neuroprotective effects of VEGF-C were lost upon cauterization of the dCLN afferent lymphatics and not mimicked by acute post-stroke VEGF-C injection. We conclude that VEGF-C prophylaxis promotes multiple vascular, immune, and neural responses that culminate in a protection against neurological damage in acute ischemic stroke.


Assuntos
AVC Isquêmico , Acidente Vascular Cerebral , Animais , Camundongos , Fator C de Crescimento do Endotélio Vascular , Doenças Neuroinflamatórias , Drenagem
18.
Transl Stroke Res ; 2023 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-37140808

RESUMO

Ischemic stroke, a disease with high mortality and disability rate worldwide, currently has no effective treatment. The systemic inflammation response to the ischemic stroke, followed by immunosuppression in focal neurologic deficits and other inflammatory damage, reduces the circulating immune cell counts and multiorgan infectious complications such as intestinal and gut dysfunction dysbiosis. Evidence showed that microbiota dysbiosis plays a role in neuroinflammation and peripheral immune response after stroke, changing the lymphocyte populations. Multiple immune cells, including lymphocytes, engage in complex and dynamic immune responses in all stages of stroke and may be a pivotal moderator in the bidirectional immunomodulation between ischemic stroke and gut microbiota. This review discusses the role of lymphocytes and other immune cells, the immunological processes in the bidirectional immunomodulation between gut microbiota and ischemic stroke, and its potential as a therapeutic strategy for ischemic stroke.

19.
Quant Imaging Med Surg ; 13(1): 293-308, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36620177

RESUMO

Background: Moyamoya disease (MMD) is a teratogenic and lethal disease. However, existing studies do not sufficiently indicate the impact factors. Therefore, we investigated the different impact factors on cerebral hemodynamics after revascularization in patients with MMD. Methods: We retrospectively collected the clinical data of 233 adult patients with MMD who underwent revascularization surgery in the Department of Neurosurgery, Renmin Hospital of Wuhan University, from January 2015 to June 2021 for this retrospective cohort study. We analyzed the effects on hemodynamic improvement of age, sex, stroke type, early symptoms, Suzuki stage, history of hypertension, history of diabetes, and history of hyperlipidemia in patients with MMD. We also evaluated the efficacy of different revascularization strategies and we verified the effect of computed tomography perfusion (CTP) in evaluating cerebral hemodynamics. Results: The CTP values demonstrated that δ cerebral blood volume (CBV) values were significantly higher in the combined group [1.01 (0.87-1.75)] relative to those in the indirect group [1.34 (1.01-1.63); P=0.027]. There was no statistical significance in the improvement of clinical symptoms and clinical prognosis between the indirect and combined groups. Patients with MMD with diabetes [δ mean transit time (MTT), 0.49 (0.35-0.70) vs. 0.72 (0.52-0.87); P<0.001] or calcium channel blocker (CCB) [δCBV, 1.46 (1.10-1.83) vs. 1.12 (0.93-1.54); P=0.001] had better cerebral hemodynamics than patients in non-diabetic group or non-CCB group after revascularization. Conclusions: We didn't find differences in clinical outcome between indirect and combined revascularization in patients with MMD. we demonstrated that CTP values can be used as a way to detect postoperative cerebral hemodynamic changes in MMD patients. Interestingly, we found that MMD patients with diabetes or CCB showed better cerebral perfusion after revascularization.

20.
Front Cardiovasc Med ; 10: 1096662, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36776247

RESUMO

Background: Serum calcium (Ca), vitamin D (VD), and vitamin K (VK) levels are key determinants of vascular calcification, which itself impacts cardiovascular disease (CVD) risk. The specific relationships between the levels of these different compounds and particular forms of CVD, however, remain to be fully defined. Objective: This study was designed to explore the associations between these serum levels and CVDs with the goal of identifying natural interventions capable of controlling vascular calcification and thereby protecting against CVD pathogenesis, extending the healthy lifespan of at-risk individuals. Methods: Linkage disequilibrium score (LDSC) regression and a two-sample Mendelian randomization (MR) framework were leveraged to systematically examine the causal interplay between these serum levels and nine forms of CVD, as well as longevity through the use of large publically accessible Genome-Wide Association Studies (GWAS) datasets. The optimal concentrations of serum Ca and VD to lower CVD risk were examined through a restrictive cubic spline (RCS) approach. Results: After Bonferroni correction, the positive genetic correlations were observed between serum Ca levels and myocardial infarction (MI) (p = 1.356E-04), as well as coronary artery disease (CAD) (p = 3.601E-04). Negative genetic correlations were detected between levels of VD and CAD (p = 0.035), while elevated VK1 concentrations were causally associated with heart failure (HF) [odds ratios (OR) per 1-standard deviation (SD) increase: 1.044], large artery stroke (LAS) (OR per 1-SD increase: 1.172), and all stroke (AS) (OR per 1-SD increase: 1.041). Higher serum Ca concentrations (OR per 1-SD increase: 0.865) and VD levels (OR per 1-SD increase: 0.777) were causally associated with reduced odds of longevity. These findings remained consistent in sensitivity analyses, and serum Ca and VD concentrations of 2.376 mmol/L and 46.8 nmol/L, respectively, were associated with a lower CVD risk (p < 0.001). Conclusion: Our findings support a genetic correlation between serum Ca and VD and CVD risk, and a causal relationship between VK1 levels and CVD risk. The optimal serum Ca (2.376 mmol/L) and VD levels (46.8 nmol/L) can reduce cardiovascular risk.

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