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2.
Sci Rep ; 14(1): 4699, 2024 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-38409583

RESUMO

Deregulation of lipid composition in adipose tissue adjacent to breast tumour is observed in ex vivo and animal models. Novel non-invasive magnetic resonance imaging (MRI) allows rapid lipid mapping of the human whole breast. We set out to elucidate the spatial heterogeneity of peri-tumoural lipid composition in postmenopausal patients with oestrogen receptor positive (ER +) breast cancer. Thirteen participants (mean age, 62 ± [SD] 6 years) with ER + breast cancer and 13 age-matched postmenopausal healthy controls were scanned on MRI. The number of double bonds in triglycerides was computed from MRI images to derive lipid composition maps of monounsaturated, polyunsaturated, and saturated fatty acids (MUFA, PUFA, SFA). The spatial heterogeneity measures (mean, median, skewness, entropy and kurtosis) of lipid composition in the peri-tumoural region and the whole breast of participants and in the whole breast of controls were computed. The Ki-67 proliferative activity marker and CD163 antibody on tumour-associated macrophages were assessed histologically. Mann Whitney U or Wilcoxon tests and Spearman's coefficients were used to assess group differences and correlations, respectively. For comparison against the whole breast in participants, peri-tumoural MUFA had a lower mean (median (IQR), 0.40 (0.02), p < .001), lower median (0.42 (0.02), p < .001), a negative skewness with lower magnitude (- 1.65 (0.77), p = .001), higher entropy (4.35 (0.64), p = .007) and lower kurtosis (5.13 (3.99), p = .001). Peri-tumoural PUFA had a lower mean (p < .001), lower median (p < .001), a positive skewness with higher magnitude (p = .005) and lower entropy (p = .002). Peri-tumoural SFA had a higher mean (p < .001), higher median (p < .001), a positive skewness with lower magnitude (p < .001) and lower entropy (p = .012). For comparison against the whole breast in controls, peri-tumoural MUFA had a negative skewness with lower magnitude (p = .01) and lower kurtosis (p = .009), however there was no difference in PUFA or SFA. CD163 moderately correlated with peri-tumoural MUFA skewness (rs = - .64), PUFA entropy (rs = .63) and SFA skewness (rs = .59). There was a lower MUFA and PUFA while a higher SFA, and a higher heterogeneity of MUFA while a lower heterogeneity of PUFA and SFA, in the peri-tumoural region in comparison with the whole breast tissue. The degree of lipid deregulation was associated with inflammation as indicated by CD163 antibody on macrophages, serving as potential marker for early diagnosis and response to therapy.


Assuntos
Neoplasias da Mama , Animais , Humanos , Pessoa de Meia-Idade , Feminino , Neoplasias da Mama/diagnóstico por imagem , Ácidos Graxos Monoinsaturados , Pós-Menopausa , Ácidos Graxos , Receptores de Estrogênio
3.
Molecules ; 28(14)2023 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-37513399

RESUMO

Parkinson's disease (PD) is an age-related, progressive neurodegenerative disease characterized by the gradual and massive loss of dopaminergic neurons in the substantia nigra pars compacta (SNc). We have recently reported that artemisinin, an FDA-approved first-line antimalarial drug, possesses a neuroprotective effect. However, the effects and underlying mechanisms of artemisinin on Parkinson's disease remain to be elucidated. In this study, we investigated the neuroprotective effects of artemisinin on 6-OHDA and MPP+ in neuronal cells and animal models, as well as the underlying mechanisms. Our results showed that artemisinin significantly attenuated the loss of cell viability, LDH release, elevated levels of reactive oxygen species (ROS), the collapse of the mitochondria trans-membrane potential and cell apoptosis in PC12 cells. Western blot results showed that artemisinin stimulated the phosphorylation of ERK1/2, its upstream signaling proteins c-Raf and MEK and its downstream target CREB in PC12 cells in a time- and concentration-dependent manner. In addition, the protective effect of artemisinin was significantly reduced when the ERK pathway was blocked using the ERK pathway inhibitor PD98059 or when the expression of ERK was knocked down using sgRNA. These results indicate the essential role of ERK in the protective effect of artemisinin. Similar results were obtained in SH-SY5Y cells and primary cultured neurons treated with 6-OHDA, as well as in cellular models of MPP+ injury. More interestingly, artemisinin attenuated PD-like behavior deficit in mice injected with 6-OHDA evaluated by behavioral tests including swimming test, pole-test, open field exploration and rotarod tests. Moreover, artemisinin also stimulated the phosphorylation of ERK1/2, inhibited apoptosis, and rescued dopaminergic neurons in SNc of these animals. Application of ERK pathway inhibitor PD98059 blocked the protective effect of artemisinin in mice during testing. Taking these results together, it was indicated that artemisinin preserves neuroprotective effects against 6-OHDA and MPP+ induced injury both in vitro and in vivo by the stimulation of the ERK1/2 signaling pathway. Our findings support the potential therapeutic effect of artemisinin in the prevention and treatment of Parkinson's disease.


Assuntos
Artemisininas , Neuroblastoma , Doenças Neurodegenerativas , Fármacos Neuroprotetores , Doença de Parkinson , Ratos , Humanos , Camundongos , Animais , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/metabolismo , Sistema de Sinalização das MAP Quinases , Oxidopamina/efeitos adversos , Fármacos Neuroprotetores/uso terapêutico , Neuroproteção , Doenças Neurodegenerativas/tratamento farmacológico , RNA Guia de Sistemas CRISPR-Cas , Neuroblastoma/tratamento farmacológico , Apoptose , Artemisininas/metabolismo , Neurônios Dopaminérgicos
4.
Am J Chin Med ; 51(3): 595-622, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36999542

RESUMO

Oxidative stress is an important contributor to the pathogenesis of Alzheimer's disease (AD). The overproduction of reactive oxygen species observed in AD patients results in the loss of mitochondrial function, altered metal ion homeostasis, lipopolysaccharide metabolism disorder, reduced anti-oxidant defense, increased release of inflammatory factors, and the aggravation and accumulation of amyloid-beta and tau hyper-phosphorylation, which directly cause synaptic and neuronal loss and lead to cognitive dysfunction. Thus, oxidative stress proves to be a fundamental part of AD development and progression, suggesting the potential benefits of anti-oxidant-based therapies for AD. In this study, we found that a water-soluble extract of Artemisia annua (WSEAA), a traditional Chinese herbal medicine, has a strong anti-oxidant function. We also found that WSEAA is able to improve the cognitive function of 3xTg AD mice. However, the mechanisms and molecular targets underlying WSEAA action are still not known. In order to uncover the potential molecular mechanisms involved, we used a combination of network pharmacology and different experimental approaches. Obtained results revealed key genes (such as AKT1, BCL2, IL-6, TNF-[Formula: see text] and BAX) and signaling pathways (like PI3K-AKT and BCL2/BAX) are closely associated with the biological processes responding to oxidative stress. Further verification of the survival/anti-oxidant effects of WSEAA in vitro and in vivo showed that the extract has anti-oxidatant/neuronal survival action against H2O2-induced damage, and is thus able to prevent the cognitive decline and pathological changes of 3xTg transgenic (3xTg) mice via the regulation of key target-genes and pathways, such as PI3K-AKT and BCL2/BAX, related to survival/apoptosis. Our findings strongly indicate the potential of WSEAA for the prevention and treatment of AD.


Assuntos
Doença de Alzheimer , Artemisia annua , Camundongos , Animais , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Artemisia annua/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Farmacologia em Rede , Antioxidantes/farmacologia , Fosfatidilinositol 3-Quinases , Peróxido de Hidrogênio , Proteína X Associada a bcl-2 , Camundongos Transgênicos
5.
Oxid Med Cell Longev ; 2021: 5574932, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34567410

RESUMO

Glucocorticoids are the most common cause of secondary osteoporosis, which affects both women (pre- and postmenopausal) and men. In cases of prolonged treatment, glucocorticoids promote the loss and inactivation of the differentiational function of bone marrow mesenchymal stromal cells (BMSCs), risking the development of skeletal system diseases such as osteoporosis. This study reports for the first time the protective effect of the antimalarial artemisinin against glucocorticoid-induced insults on primary cultured rat BMSCs. At relatively low concentrations, artemisinin treatment improved BMSC survival by promoting a decline of reactive oxygen species (ROS) production that correlated with the decrease of caspase-3 activation, LDH release, mitochondrial membrane potential (Δψm) loss, and apoptosis induced by dexamethasone (DEXA). In addition, artemisinin improved the osteogenic differentiation of DEXA-damaged cells. DEXA inhibited extracellular-signal-regulated kinase 1/2 (ERK1/2) and cAMP response element binding protein (CREB) phosphorylation, and artemisinin treatment promoted their activation in a concentration-dependent manner. PD98059, the specific inhibitor of the ERK1/2 pathway, blocked ERK1/2 phosphorylation and artemisinin protection. Similarly, siCREB attenuated the protective effect of artemisinin, strongly suggesting the involvement of the ERK1/2-CREB pathway in the protective action of artemisinin against DEXA-induced damage in BMSCs. In addition, we found that the expression of antiapoptotic protein B-cell lymphoma 2 protein (BCL-2) was also upregulated by artemisinin. These studies demonstrate the therapeutic potential of artemisinin in the survival improvement of BMSCs exposed to glucocorticoid-induced apoptosis and suggest that artemisinin-mediated protection may occur via the activation of ERK1/2-CREB signaling pathway.


Assuntos
Artemisininas/farmacologia , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Glucocorticoides/metabolismo , Células-Tronco Mesenquimais/efeitos dos fármacos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Anti-Infecciosos/farmacologia , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Humanos , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/patologia , Proteína Quinase 1 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/genética
6.
Stem Cell Res Ther ; 12(1): 174, 2021 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-33712072

RESUMO

BACKGROUND: Spinal cord injury (SCI) is a debilitating medical condition that can result in the irreversible loss of sensorimotor function. Current therapies fail to provide an effective recovery being crucial to develop more effective approaches. Mesenchymal stem cell (MSC) exosomes have been shown to be able to facilitate axonal growth and act as mediators to regulate neurogenesis and neuroprotection, holding great therapeutic potential in SCI conditions. This study aimed to assess the potential of human placental MSC (hpMSC)-derived exosomes on the functional recovery and reactivation of endogenous neurogenesis in an experimental animal model of SCI and to explore the possible mechanisms involved. METHODS: The hpMSC-derived exosomes were extracted and transplanted in an experimental animal model of SCI with complete transection of the thoracic segment. Functional recovery, the expression of neural stem/progenitor cell markers and the occurrence of neurogenesis, was assessed 60 days after the treatment. In vitro, neural stem cells (NSCs) were incubated with the isolated exosomes for 24 h, and the phosphorylation levels of mitogen-activated protein kinase kinase (MEK), extracellular signal-regulated kinases (ERK), and cAMP response element binding (CREB) proteins were assessed by western blot. RESULTS: Exosomes were successfully isolated and purified from hpMSCs. Intravenous injections of these purified exosomes significantly improved the locomotor activity and bladder dysfunction of SCI animals. Further study of the exosomes' therapeutic action revealed that hpMSC-derived exosomes promoted the activation of proliferating endogenous neural stem/progenitor cells as denoted by the significant increase of spinal SOX2+GFAP+, PAX6+Nestin+, and SOX1+KI67+ cells. Moreover, animals treated with exosomes exhibited a significative higher neurogenesis, as indicated by the higher percentage of DCX+MAP 2+ neurons. In vitro, hpMSC-derived exosomes promoted the proliferation of NSCs and the increase of the phosphorylated levels of MEK, ERK, and CREB. CONCLUSIONS: This study provides evidence that the use of hpMSC-derived exosomes may constitute a promising therapeutic strategy for the treatment of SCI.


Assuntos
Exossomos , Células-Tronco Mesenquimais , Traumatismos da Medula Espinal , Animais , Feminino , Humanos , Neurogênese , Placenta , Gravidez , Recuperação de Função Fisiológica , Medula Espinal , Traumatismos da Medula Espinal/terapia
7.
Food Chem ; 192: 351-7, 2016 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-26304358

RESUMO

In this paper, L-cysteine/graphene-CS/GCE (L-cys/GR-CS/GCE) was prepared successfully, and its electrochemical properties were characterized by cyclic voltammetry (CV) and electrochemical AC impedance. Moreover, the electrochemical behaviors of Cd(2+) and Pb(2+) on the proposed electrode were studied by differential pulse anodic stripping voltammetry (DPASV). Experimental parameters, such as the deposition potential and time, the pH value of buffer solution, were optimized. Under the optimized conditions, the linear equations of the DPASV response current with Cd(2+) and Pb(2+) concentration were I (µA) = 0.745 C (µg/L)+4.539 (R = 0.9986), I (µA) = 0.437 C (µg/L)+2.842 (R = 0.9983), respectively, and the detection limit was 0.45 and 0.12 µg/L, respectively. Finally, L-cys/GR-CS/GCE was used to detect Cd(2+) and Pb(2+) in practical samples, and the results were compared with ICP-AES. This idea and method will provide a new approach for food security evaluation.


Assuntos
Cádmio/análise , Cisteína/química , Técnicas Eletroquímicas/métodos , Grafite/química , Chumbo/análise , Eletrodos , Limite de Detecção , Microscopia Eletrônica de Transmissão , Propriedades de Superfície
8.
J Photochem Photobiol B ; 123: 32-40, 2013 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-23608671

RESUMO

Polycyclic aromatic hydrocarbons derivatives (PAHs) have been confirmed to be carcinogenic, teratogenic and mutagenic, and have the potential to cause human malignant diseases. In this work, interactions of two selected amino-PAHs (aminopyrene derivatives) and human tumor-related DNA were evaluated using spectroscopic and polyacrylamide gel electrophoresis (PAGE) methods. Spectroscopic results demonstrated that there were remarkable interactions between PAHs and the targeted DNA with the order of the binding ability as 1-AP>1-PBA. The binding constants of 1-AP with the targeted DNA were at the level of about 10(6) L/mol, while that of 1-PBA only to about 10(3) L/mol. 1-AP with a short side-chain acted mainly as an intercalator, and its interactions with DNA were strengthened with electrostatic forces. As for 1-PBA with a flexible long side-chain, the intercalation mode was dominated with an auxiliary role of Van der Wals forces and hydrogen bonds. Besides, the binding abilities of amino-PAHs to p53 DNA seemed stronger than that for C-myc DNA. PAGE results showed that the binding of amino-PAHs could further change the conformation of DNA sequences from the duplex to the antiparallel G-quadruplex.


Assuntos
Butilaminas/química , DNA/química , Genes myc , Substâncias Intercalantes/química , Pirenos/química , Proteína Supressora de Tumor p53/genética , Carcinógenos , Dicroísmo Circular , Eletroforese em Gel de Poliacrilamida , Humanos , Mutagênicos , Conformação de Ácido Nucleico/efeitos dos fármacos , Concentração Osmolar , Hidrocarbonetos Policíclicos Aromáticos/química , Iodeto de Potássio/química , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Termodinâmica
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