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1.
Life Sci ; 296: 120435, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35247437

RESUMO

AIMS: Glioblastoma (GBM) is the most common and deadliest type of brain cancer, and the current therapeutic options are not curative, imposing the need for novel strategies. Asiatic acid (AA) is a natural compound and has been explored due to its anti-glioma activity and lower toxicity to healthy tissues compared with conventional chemotherapeutic agents. However, its poor water-solubility is an obstacle for clinical application. Poly(lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) were proposed in this work for Asiatic acid (AA) delivery. MAIN METHODS: A central composite design was implemented to optimize the NPs, and their surface was further modified with transferrin (Tf), for targeted delivery to GBM cells. The anti-glioma activity of the NPs was studied in vitro using human GBM cells and immortalized human astrocytes. KEY FINDINGS: The NPs exhibited a mean size smaller than 200 nm, with low polydispersity and negative zeta potential, indicating their suitability for brain tumor delivery. The NPs also exhibited high encapsulation efficiency and maintained a slow and controlled release of AA for 20 days. In vitro cell studies showed that NPs were able to maintain the anti-glioma activity of the natural compound and that the surface modification with Tf molecules was able to increase the cellular uptake in GBM cells, enhancing their selectivity and decreasing toxicity in healthy cells. SIGNIFICANCE: Overall, this work provided guidance for designing brain-targeting delivery systems of natural compounds.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Glioblastoma/tratamento farmacológico , Nanopartículas/administração & dosagem , Triterpenos Pentacíclicos/administração & dosagem , Transferrina/química , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/farmacocinética , Antineoplásicos Fitogênicos/farmacologia , Astrócitos/efeitos dos fármacos , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Glioblastoma/patologia , Humanos , Nanopartículas/química , Triterpenos Pentacíclicos/farmacocinética , Triterpenos Pentacíclicos/farmacologia , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Receptores da Transferrina/metabolismo
2.
Eur J Pharm Biopharm ; 173: 121-131, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35283304

RESUMO

The blood-brain barrier (BBB) is a strong barrier against the entrance of drugs, which has made brain cancer treatment a major challenge. We have previously shown that targeting transferrin receptors using aptamers increased brain drug delivery. To get a better understanding of this phenomenon, in the present article, a mathematical model based on the finite element method was developed accounting for the fluid flow and mass transport of the aptamer molecule inside an 8 µm capillary vessel across a 14 µm blood-brain barrier domain. The fluid flow and mass transport equations were coupled to calculate the blood velocity and aptamer concentration profiles across the BBB. It was identified that the thickness of the astrocyte and endothelial cell layers are key parameters affecting the concentration of the aptamer delivered to the last neuron dendrites in the BBB. The predicted efficacy of the drug delivery (Capt/Cin) of 10.9% to 13.8% was calculated at a porosity of 0.5 to 0.9, respectively, at a blood velocity of 0.38 mm/s, which was independent of the inlet concentration of the aptamer. This low efficacy was attributed to the mass transfer resistance across endothelial cells, astrocyte and pericyte layers, which decreased the concentration by 6.7%. It was also identified that the main mechanism of drug delivery is switched from convective mass transport in the capillary layer (with Peclet number > 50) to mixed convection mass transport (1 < Peclet number < 5) in the porous layers and to diffusion only once aptamer reached the brain parenchyma (Peclet number < 1).


Assuntos
Barreira Hematoencefálica , Neoplasias Encefálicas , Transporte Biológico , Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Neoplasias Encefálicas/tratamento farmacológico , Células Endoteliais/metabolismo , Humanos , Receptores da Transferrina/metabolismo , Receptores da Transferrina/uso terapêutico
3.
Oncogene ; 41(18): 2587-2596, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35338344

RESUMO

Diffuse-type gastric cancer (DGC) is a highly invasive subtype of gastric adenocarcinoma that frequently exhibits scattered peritoneal metastasis. Previous studies have shown that the genes of receptor tyrosine kinases (RTKs), such as fibroblast growth factor receptor 2 (FGFR2) or Met, are amplified in some DGC cell lines, leading to the constitutive activation of corresponding RTKs. In these cell lines, the survival of cancer cells appears to be dependent on the activation of RTKs. To gain novel insights into the downstream signaling pathways of RTKs specific to DGC, phosphotyrosine-containing proteins associated with activated FGFR2 were purified through two sequential rounds of immunoprecipitation from the lysates of two DGC cell lines. As a result, transferrin receptor 1 (TfR1) was identified as the binding partner of FGFR2. Biochemical analysis confirmed that TfR1 protein binds to FGFR2 and is phosphorylated at tyrosine 20 (Tyr20) in an FGFR2 kinase activity-dependent manner. The knockdown of TfR1 and treatment with an inhibitor of FGFR2 caused significant impairment in iron uptake and suppression of cellular proliferation in vitro. Moreover, the suppression of expression levels of TfR1 in the DGC cells significantly reduced their tumorigenicity and potency of peritoneal dissemination. It was indicated that TfR1, when phosphorylated by the binding partner FGFR2 in DGC cells, promotes proliferation and tumorigenicity of these cancer cells. These results suggest that the control of TfR1 function may serve as a therapeutic target in DGC with activated FGFR2.


Assuntos
Neoplasias Gástricas , Linhagem Celular Tumoral , Humanos , Fosforilação , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos , Receptores da Transferrina/genética , Receptores da Transferrina/metabolismo , Neoplasias Gástricas/patologia , Tirosina/metabolismo
4.
J Exp Med ; 219(3)2022 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-35226042

RESUMO

Delivery of biotherapeutics across the blood-brain barrier (BBB) is a challenge. Many approaches fuse biotherapeutics to platforms that bind the transferrin receptor (TfR), a brain endothelial cell target, to facilitate receptor-mediated transcytosis across the BBB. Here, we characterized the pharmacological behavior of two distinct TfR-targeted platforms fused to iduronate 2-sulfatase (IDS), a lysosomal enzyme deficient in mucopolysaccharidosis type II (MPS II), and compared the relative brain exposures and functional activities of both approaches in mouse models. IDS fused to a moderate-affinity, monovalent TfR-binding enzyme transport vehicle (ETV:IDS) resulted in widespread brain exposure, internalization by parenchymal cells, and significant substrate reduction in the CNS of an MPS II mouse model. In contrast, IDS fused to a standard high-affinity bivalent antibody (IgG:IDS) resulted in lower brain uptake, limited biodistribution beyond brain endothelial cells, and reduced brain substrate reduction. These results highlight important features likely to impact the clinical development of TfR-targeting platforms in MPS II and potentially other CNS diseases.


Assuntos
Iduronato Sulfatase , Mucopolissacaridose II , Receptores da Transferrina , Proteínas Recombinantes de Fusão , Animais , Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Modelos Animais de Doenças , Células Endoteliais/metabolismo , Iduronato Sulfatase/metabolismo , Iduronato Sulfatase/farmacologia , Lisossomos/metabolismo , Camundongos , Mucopolissacaridose II/metabolismo , Receptores da Transferrina/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Recombinantes de Fusão/farmacologia , Distribuição Tecidual
5.
Int J Mol Sci ; 23(3)2022 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-35163558

RESUMO

A subpopulation of neurons is less vulnerable against iron-induced oxidative stress and neurodegeneration. A key feature of these neurons is a special extracellular matrix composition that forms a perineuronal net (PN). The PN has a high affinity to iron, which suggests an adapted iron sequestration and metabolism of the ensheathed neurons. Highly active, fast-firing neurons-which are often ensheathed by a PN-have a particular high metabolic demand, and therefore may have a higher need in iron. We hypothesize that PN-ensheathed neurons have a higher intracellular iron concentration and increased levels of iron proteins. Thus, analyses of cellular and regional iron and the iron proteins transferrin (Tf), Tf receptor 1 (TfR), ferritin H/L (FtH/FtL), metal transport protein 1 (MTP1 aka ferroportin), and divalent metal transporter 1 (DMT1) were performed on Wistar rats in the parietal cortex (PC), subiculum (SUB), red nucleus (RN), and substantia nigra (SNpr/SNpc). Neurons with a PN (PN+) have higher iron concentrations than neurons without a PN: PC 0.69 mM vs. 0.51 mM, SUB 0.84 mM vs. 0.69 mM, SN 0.71 mM vs. 0.63 mM (SNpr)/0.45 mM (SNpc). Intracellular Tf, TfR and MTP1 contents of PN+ neurons were consistently increased. The iron concentration of the PN itself is not increased. We also determined the percentage of PN+ neurons: PC 4%, SUB 5%, SNpr 45%, RN 86%. We conclude that PN+ neurons constitute a subpopulation of resilient pacemaker neurons characterized by a bustling iron metabolism and outstanding iron handling capabilities. These properties could contribute to the low vulnerability of PN+ neurons against iron-induced oxidative stress and degeneration.


Assuntos
Proteínas de Ligação ao Ferro/metabolismo , Ferro/metabolismo , Nervos Periféricos/metabolismo , Animais , Apoferritinas/metabolismo , Proteínas de Transporte de Cátions/metabolismo , Metabolismo Energético , Regulação da Expressão Gênica , Masculino , Ratos , Ratos Wistar , Receptores da Transferrina/metabolismo , Transferrina/metabolismo
6.
Fluids Barriers CNS ; 19(1): 1, 2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-34983574

RESUMO

BACKGROUND: Brain capillary endothelial cells (BCECs) experience hypoxic conditions during early brain development. The newly formed capillaries are tight and functional before astrocytes and pericytes join the capillaries and establish the neurovascular unit. Brain endothelial cell phenotype markers P-gp (ABCB1), LAT-1(SLC7A5), GLUT-1(SLC2A1), and TFR(TFRC) have all been described to be hypoxia sensitive. Therefore, we hypothesized that monolayers of BCECs, cultured under hypoxic conditions, would show an increase in LAT-1, GLUT-1 and TFR expression and display tight endothelial barriers. METHODS AND RESULTS: Primary bovine BCECs were cultured under normoxic and hypoxic conditions. Chronic hypoxia induced HIF-1α stabilization and translocation to the nucleus, as judged by immunocytochemistry and confocal laser scanning imaging. Endothelial cell morphology, claudin-5 and ZO-1 localization and barrier integrity were unaffected by hypoxia, indicating that the tight junctions in the BBB model were not compromised. SLC7A5, SLC2A1, and TFRC-mRNA levels were increased in hypoxic cultures, while ABCB1 remained unchanged as shown by real-time qPCR. P-gp, TfR and GLUT-1 were found to be significantly increased at protein levels. An increase in uptake of [3H]-glucose was demonstrated, while a non-significant increase in the efflux ratio of the P-gp substrate [3H]-digoxin was observed in hypoxic cells. No changes were observed in functional LAT-1 as judged by uptake studies of [3H]-leucine. Stabilization of HIF-1α under normoxic conditions with desferrioxamine (DFO) mimicked the effects of hypoxia on endothelial cells. Furthermore, low concentrations of DFO caused an increase in transendothelial electrical resistance (TEER), suggesting that a slight activation of the HIF-1α system may actually increase brain endothelial monolayer tightness. Moreover, exposure of confluent monolayers to hypoxia resulted in markedly increase in TEER after 24 and 48 h, which corresponded to a higher transcript level of CLDN5. CONCLUSIONS: Our findings collectively suggest that hypoxic conditions increase some BBB transporters' expression via HIF-1α stabilization, without compromising monolayer integrity. This may in part explain why brain capillaries show early maturation, in terms of barrier tightness and protein expression, during embryogenesis, and provides a novel methodological tool for optimal brain endothelial culture.


Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Barreira Hematoencefálica/metabolismo , Células Endoteliais/metabolismo , Endotélio Vascular/metabolismo , Transportador 2 de Aminoácido Excitatório/metabolismo , Hipóxia/metabolismo , Transportador 1 de Aminoácidos Neutros Grandes/metabolismo , Receptores da Transferrina/metabolismo , Animais , Bovinos , Células Cultivadas
7.
Nat Commun ; 13(1): 558, 2022 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-35091550

RESUMO

Five New World mammarenaviruses (NWMs) cause life-threatening hemorrhagic fever (HF). Cellular entry by these viruses is mediated by human transferrin receptor 1 (hTfR1). Here, we demonstrate that an antibody (ch128.1/IgG1) which binds the apical domain of hTfR1, potently inhibits infection of attenuated and pathogenic NWMs in vitro. Computational docking of the antibody Fab crystal structure onto the known structure of hTfR1 shows an overlapping receptor-binding region shared by the Fab and the viral envelope glycoprotein GP1 subunit that binds hTfR1, and we demonstrate competitive inhibition of NWM GP1 binding by ch128.1/IgG1 as the principal mechanism of action. Importantly, ch128.1/IgG1 protects hTfR1-expressing transgenic mice against lethal NWM challenge. Additionally, the antibody is well-tolerated and only partially reduces ferritin uptake. Our findings provide the basis for the development of a novel, host receptor-targeted antibody therapeutic broadly applicable to the treatment of HF of NWM etiology.


Assuntos
Antígenos CD/metabolismo , Arenaviridae/metabolismo , Febre Hemorrágica Americana/metabolismo , Receptores da Transferrina/metabolismo , Proteínas do Envelope Viral/metabolismo , Células A549 , Animais , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/metabolismo , Anticorpos Monoclonais/farmacologia , Antígenos CD/imunologia , Arenaviridae/efeitos dos fármacos , Arenaviridae/fisiologia , Chlorocebus aethiops , Febre Hemorrágica Americana/prevenção & controle , Febre Hemorrágica Americana/virologia , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Humanos , Vírus Junin/efeitos dos fármacos , Vírus Junin/fisiologia , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Simulação de Acoplamento Molecular , Ligação Proteica/efeitos dos fármacos , Receptores da Transferrina/antagonistas & inibidores , Receptores da Transferrina/imunologia , Células Vero
8.
Exp Eye Res ; 216: 108947, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35074344

RESUMO

Zebrafish possess the ability to completely regenerate the retina following injury, however little is understood about the damage signals that contribute to inducing Müller glia reprogramming and proliferation to regenerate lost neurons. Multiple studies demonstrated that iron contributes to various retinal injuries, however no link has been shown between iron and zebrafish retinal regeneration. Here we demonstrate that Müller glia exhibit transcriptional changes following injury to regulate iron levels within the retina, allowing for increased iron uptake and decreased export. The response of the zebrafish retina to intravitreal iron injection was then characterized, showing that ferrous, and not ferric, iron induces retinal cell death. Additionally, iron chelation resulted in decreased numbers of TUNEL-positive photoreceptors and fewer proliferating Müller glia. Despite the contribution of iron to retinal cell death, inhibition of ferroptosis did not significantly reduce cell death following light treatment. Finally, we demonstrate that both the anti-ferroptotic protein Glutathione peroxidase 4b and the Transferrin receptor 1b are required for Müller glia proliferation following light damage. Together these findings show that iron contributes to cell death in the light-damaged retina and is essential for inducing the Müller glia regeneration response.


Assuntos
Proliferação de Células/efeitos dos fármacos , Células Ependimogliais/efeitos dos fármacos , Compostos Ferrosos/toxicidade , Células Fotorreceptoras/efeitos dos fármacos , Lesões Experimentais por Radiação/etiologia , Degeneração Retiniana/induzido quimicamente , Animais , Animais Geneticamente Modificados , Apoptose , Deferiprona/farmacologia , Células Ependimogliais/metabolismo , Marcação In Situ das Extremidades Cortadas , Injeções Intravítreas , Luz , Fosfolipídeo Hidroperóxido Glutationa Peroxidase/metabolismo , Células Fotorreceptoras/efeitos da radiação , Lesões Experimentais por Radiação/metabolismo , Receptores da Transferrina/metabolismo , Degeneração Retiniana/metabolismo , Peixe-Zebra , Proteínas de Peixe-Zebra/metabolismo
9.
Sci Rep ; 12(1): 1297, 2022 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-35079042

RESUMO

Δ9-tetrahydrocannabinol (Δ9-THC) is known for its antitumor activity and palliative effects. However, its unfavorable physicochemical and biopharmaceutical properties, including low bioavailability, psychotropic side effects and resistance mechanisms associated to dosing make mandatory the development of successful drug delivery systems. In this work, transferring (Tf) surface-modified Δ9-THC-loaded poly(lactide-co-glycolic) nanoparticles (Tf-THC-PLGA NPs) were proposed and evaluated as novel THC-based anticancer therapy. Furthermore, in order to assess the interaction of both the nanocarrier and the loaded drug with cancer cells, a double-fluorescent strategy was applied, including the chemical conjugation of a dye to the nanoparticle polymer along with the encapsulation of either a lipophilic or a hydrophilic dye. Tf-THC PLGA NPs exerted a cell viability decreased down to 17% vs. 88% of plain nanoparticles, while their internalization was significantly slower than plain nanoparticles. Uptake studies in the presence of inhibitors indicated that the nanoparticles were internalized through cholesterol-associated and clathrin-mediated mechanisms. Overall, Tf-modification of PLGA NPs showed to be a highly promising approach for Δ9-THC-based antitumor therapies, potentially maximizing the amount of drug released in a sustained manner at the surface of cells bearing cannabinoid receptors.


Assuntos
Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Neoplasias do Colo/metabolismo , Dronabinol/metabolismo , Dronabinol/farmacologia , Liberação Controlada de Fármacos , Nanopartículas/química , Receptores de Canabinoides/metabolismo , Células CACO-2 , Cápsulas , Sobrevivência Celular/efeitos dos fármacos , Neoplasias do Colo/patologia , Humanos , Ligantes , Tamanho da Partícula , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Receptores da Transferrina/metabolismo , Transferrina/química , Transferrina/metabolismo
10.
Am J Physiol Renal Physiol ; 322(1): F89-F103, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34843656

RESUMO

Chronic kidney disease involves disturbances in iron metabolism including anemia caused by insufficient erythropoietin (EPO) production. However, underlying mechanisms responsible for the dysregulation of cellular iron metabolism are incompletely defined. Using the unilateral ureteral obstruction (UUO) model in Irp1+/+ and Irp1-/- mice, we asked if iron regulatory proteins (IRPs), the central regulators of cellular iron metabolism and suppressors of EPO production, contribute to the etiology of anemia in kidney failure. We identified a significant reduction in IRP protein level and RNA binding activity that associates with a loss of the iron uptake protein transferrin receptor 1 (TfR1), increased expression of the iron storage protein subunits H- and L-ferritin, and a low but overall variable level of stainable iron in the obstructed kidney. This reduction in IRP RNA binding activity and ferritin RNA levels suggests the concomitant rise in ferritin expression and iron content in kidney failure is IRP dependent. In contrast, the reduction in the Epo mRNA level in the obstructed kidney was not rescued by genetic ablation of IRP1, suggesting disruption of normal hypoxia-inducible factor (HIF)-2α regulation. Furthermore, reduced expression of some HIF-α target genes in UUO occurred in the face of increased expression of HIF-α proteins and prolyl hydroxylases 2 and 1, the latter of which is not known to be HIF-α mediated. Our results suggest that the IRP system drives changes in cellular iron metabolism that are associated with kidney failure in UUO but that the impact of IRPs on EPO production is overridden by disrupted hypoxia signaling.NEW & NOTEWORTHY This study demonstrates that iron metabolism and hypoxia signaling are dysregulated in unilateral obstructive nephropathy. Expression of iron regulatory proteins (IRPs), central regulators of cellular iron metabolism, and the iron uptake (transferrin receptor 1) and storage (ferritins) proteins they target is strongly altered. This suggests a role of IRPs in previously observed changes in iron metabolism in progressive renal disease. Hypoxia signaling is disrupted and appeared to dominate the action of IRP1 in controlling erythropoietin expression.


Assuntos
Anemia/etiologia , Ferro/metabolismo , Rim/metabolismo , Insuficiência Renal/etiologia , Obstrução Ureteral/complicações , Anemia/metabolismo , Anemia/patologia , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Hipóxia Celular , Modelos Animais de Doenças , Eritropoetina/genética , Eritropoetina/metabolismo , Ferritinas/genética , Ferritinas/metabolismo , Fibrose , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Prolina Dioxigenases do Fator Induzível por Hipóxia/genética , Prolina Dioxigenases do Fator Induzível por Hipóxia/metabolismo , Proteína 1 Reguladora do Ferro/genética , Proteína 1 Reguladora do Ferro/metabolismo , Rim/patologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pró-Colágeno-Prolina Dioxigenase/genética , Pró-Colágeno-Prolina Dioxigenase/metabolismo , Receptores da Transferrina/genética , Receptores da Transferrina/metabolismo , Insuficiência Renal/metabolismo , Insuficiência Renal/patologia , Obstrução Ureteral/metabolismo , Obstrução Ureteral/patologia
11.
Leuk Res ; 112: 106755, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34844140

RESUMO

Iron deficiency (ID) and iron deficiency anemia (IDA) have many adverse effects on human health. Also, iron deficiency anemia and anemia in general are linked with an increased risk of various cancers, particularly blood cancers. It is known that subjects with IDA as well as smokers have elevated blood levels of toxic divalent cations, particularly cadmium (Cd2+) and lead (Pb2+). Cadmium is a proven carcinogen. Most of the circulating cadmium is bound to transferrin and apart from the target organs of cadmium accumulation, kidney and liver, tissues (cells) which highly express transferrin receptor 1 (TfR1) may also accumulate high levels of circulating cadmium. Density of TfR1, glycoprotein that is expressed on cell surface, is not uniform in bone marrow cells. Namely, megakaryocyte/erythrocyte progenitors and pro-erythroblasts express TfR1 incomparably more than other cell lines within the bone marrow and we hypothesize that the mentioned cell lines will uptake most of the circulating cadmium and lead, and will consequently be most suitable for malignant transformation. In this review, we discuss in detail the mechanisms involved in accumulation of cadmium in particular cell lines of the bone marrow and the consequent occurrence of acute myeloid leukemia (AML).


Assuntos
Anemia Ferropriva/sangue , Cádmio/sangue , Transformação Celular Neoplásica , Chumbo/sangue , Leucemia Mieloide/sangue , Metais Pesados/sangue , Doença Aguda , Anemia Ferropriva/complicações , Anemia Ferropriva/metabolismo , Antígenos CD/metabolismo , Células da Medula Óssea/metabolismo , Cádmio/metabolismo , Eritroblastos/metabolismo , Humanos , Chumbo/metabolismo , Leucemia Mieloide/etiologia , Leucemia Mieloide/metabolismo , Metais Pesados/metabolismo , Modelos Biológicos , Receptores da Transferrina/metabolismo
12.
Sci China Life Sci ; 65(2): 328-340, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34482518

RESUMO

Engineered nanocarriers have been widely developed for tumor theranostics. However, the delivery of imaging probes or therapeutic drugs to the tumor pre-formation site for early and accurate detection and therapy remains a major challenge. Here, by using tailor-functionalized human H-ferritin (HFn), we developed a triple-modality nanoprobe IRdye800-M-HFn and achieved the early imaging of tumor cells before the formation of solid tumor tissues. Then, we developed an HFn-doxorubicin (Dox) drug delivery system by loading Dox into the HFn protein cage and achieved early-stage tumor therapy. The intravenous injection of HFn nanoprobes enabled the imaging of tumor cells as early as two days after tumor implantation, and the triple-modality imaging techniques, namely, near-infrared fluorescence molecular imaging (NIR-FMI), magnetic resonance imaging (MRI), and photoacoustic imaging (PAI), ensured the accuracy of detection. Further exploration indicated that HFn could specifically penetrate into pre-solid tumor sites by tumor-associated inflammation-mediated blood vessel leakage, followed by effective accumulation in tumor cells by the specific targeting property of HFn to transferrin receptor 1. Thus, the HFn-Dox drug delivery system delivered Dox into the tumor pre-formation site and effectively killed tumor cells at early stage. IRDye800-M-HFn nanoprobes and HFn-Dox provide promising strategies for early-stage tumor diagnosis and constructive implications for early-stage tumor treatment.


Assuntos
Ferritinas/administração & dosagem , Nanopartículas de Magnetita/administração & dosagem , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Medicina de Precisão/métodos , Animais , Antígenos CD/metabolismo , Doxorrubicina/administração & dosagem , Doxorrubicina/química , Sistemas de Liberação de Medicamentos , Detecção Precoce de Câncer , Ferritinas/química , Ferritinas/metabolismo , Células Hep G2 , Humanos , Indóis/administração & dosagem , Indóis/química , Inflamação , Imageamento por Ressonância Magnética , Nanopartículas de Magnetita/química , Camundongos , Imagem Multimodal , Neoplasias/metabolismo , Técnicas Fotoacústicas , Ligação Proteica , Receptores da Transferrina/metabolismo , Espectroscopia de Luz Próxima ao Infravermelho , Ensaios Antitumorais Modelo de Xenoenxerto
14.
ACS Appl Mater Interfaces ; 14(1): 32-40, 2022 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-34928139

RESUMO

Uveal melanoma (UM) is the most common primary intraocular malignancy among adults. Despite significant advances in diagnosis and treatment, the general mortality of UM remains alarmingly high. This calls for the development of new approaches for the treatment of UM, such as targeted cancer therapy. CD71, also known as transferrin receptor 1, is overexpressed in UM cell lines and tissues. Herein, we report the development of a CD71-specific aptamer targeting the XQ-2d-MMAE conjugate that can distinguish UM cells from normal human uveal melanocytes. The cytotoxic drug monomethyl auristatin E (MMAE) could be easily coupled onto XQ-2d, a DNA aptamer that specifically targets CD71, to achieve efficiently targeted cancer growth inhibition in a mouse xenograft model, thus implying that XQ-2d-MMAE might be developed into a promising novel anti-tumor agent for the treatment of UM. Collectively, our results demonstrated that CD71 is a reliable target for drug delivery in UM and could be utilized as a model to explore aptamer-mediated targeted UM treatment strategies.


Assuntos
Antineoplásicos/uso terapêutico , Aptâmeros de Nucleotídeos/uso terapêutico , Melanoma/tratamento farmacológico , Oligopeptídeos/uso terapêutico , Neoplasias Uveais/tratamento farmacológico , Animais , Antígenos CD/metabolismo , Antineoplásicos/metabolismo , Aptâmeros de Nucleotídeos/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Melanoma/metabolismo , Camundongos Nus , Receptores da Transferrina/metabolismo , Neoplasias Uveais/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Commun Biol ; 4(1): 1384, 2021 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-34893694

RESUMO

CD71+ erythroid cells (CECs) have been recently recognized in both neonates and cancer patients as potent immunoregulatory cells. Here, we show that in mice early-stage CECs expand in anemia, have high levels of arginase 2 (ARG2) and reactive oxygen species (ROS). In the spleens of anemic mice, CECs expansion-induced L-arginine depletion suppresses T-cell responses. In humans with anemia, CECs expand and express ARG1 and ARG2 that suppress T-cells IFN-γ production. Moreover, bone marrow CECs from healthy human donors suppress T-cells proliferation. CECs differentiated from peripheral blood mononuclear cells potently suppress T-cell activation, proliferation, and IFN-γ production in an ARG- and ROS-dependent manner. These effects are the most prominent for early-stage CECs (CD71highCD235adim cells). The suppressive properties disappear during erythroid differentiation as more differentiated CECs and mature erythrocytes lack significant immunoregulatory properties. Our studies provide a novel insight into the role of CECs in the immune response regulation.


Assuntos
Células Eritroides/imunologia , Tolerância Imunológica , Linfócitos T/imunologia , Adulto , Animais , Antígenos CD/metabolismo , Linhagem Celular , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Receptores da Transferrina/metabolismo , Adulto Jovem
16.
Nat Commun ; 12(1): 7334, 2021 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-34921133

RESUMO

The erythroid terminal differentiation program couples sequential cell divisions with progressive reductions in cell size. The erythropoietin receptor (EpoR) is essential for erythroblast survival, but its other functions are not well characterized. Here we use Epor-/- mouse erythroblasts endowed with survival signaling to identify novel non-redundant EpoR functions. We find that, paradoxically, EpoR signaling increases red cell size while also increasing the number and speed of erythroblast cell cycles. EpoR-regulation of cell size is independent of established red cell size regulation by iron. High erythropoietin (Epo) increases red cell size in wild-type mice and in human volunteers. The increase in mean corpuscular volume (MCV) outlasts the duration of Epo treatment and is not the result of increased reticulocyte number. Our work shows that EpoR signaling alters the relationship between cycling and cell size. Further, diagnostic interpretations of increased MCV should now include high Epo levels and hypoxic stress.


Assuntos
Ciclo Celular , Tamanho Celular , Eritrócitos/citologia , Eritrócitos/metabolismo , Eritropoese , Receptores da Eritropoetina/metabolismo , Adulto , Animais , Antígenos CD/metabolismo , Antígenos CD4/metabolismo , Diferenciação Celular , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Sobrevivência Celular , Inibidor de Quinase Dependente de Ciclina p27/metabolismo , Embrião de Mamíferos/metabolismo , Eritroblastos/citologia , Eritroblastos/efeitos dos fármacos , Eritroblastos/metabolismo , Eritropoetina/administração & dosagem , Eritropoetina/farmacologia , Feminino , Feto/metabolismo , Voluntários Saudáveis , Humanos , Ferro/metabolismo , Fígado/embriologia , Fígado/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Modelos Biológicos , Receptores da Transferrina/metabolismo , Reticulócitos/citologia , Reticulócitos/efeitos dos fármacos , Reticulócitos/metabolismo , Transdução de Sinais , Proteína bcl-X/metabolismo
17.
Genes (Basel) ; 12(12)2021 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-34946929

RESUMO

Hereditary hemochromatosis (HH) is an iron metabolism disease clinically characterized by excessive iron deposition in parenchymal organs such as liver, heart, pancreas, and joints. It is caused by mutations in at least five different genes. HFE hemochromatosis is the most common type of hemochromatosis, while non-HFE related hemochromatosis are rare cases. Here, we describe six new patients of non-HFE related HH from five different families. Two families (Family 1 and 2) have novel nonsense mutations in the HFE2 gene have novel nonsense mutations (p.Arg63Ter and Asp36ThrfsTer96). Three families have mutations in the TFR2 gene, one case has one previously unreported mutation (Family A-p.Asp680Tyr) and two cases have known pathogenic mutations (Family B and D-p.Trp781Ter and p.Gln672Ter respectively). Clinical, biochemical, and genetic data are discussed in all these cases. These rare cases of non-HFE related hereditary hemochromatosis highlight the importance of an earlier molecular diagnosis in a specialized center to prevent serious clinical complications.


Assuntos
Proteínas Ligadas por GPI/genética , Proteína da Hemocromatose/genética , Hemocromatose/genética , Receptores da Transferrina/genética , Adulto , Códon sem Sentido/genética , Feminino , Proteínas Ligadas por GPI/metabolismo , Hemocromatose/fisiopatologia , Proteína da Hemocromatose/metabolismo , Antígenos de Histocompatibilidade Classe I/metabolismo , Humanos , Ferro/metabolismo , Fígado/metabolismo , Masculino , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Linhagem , Receptores da Transferrina/metabolismo
18.
Sci Rep ; 11(1): 22121, 2021 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-34764389

RESUMO

Arsenic exposure poses numerous threats to human health. Our previous work in mice has shown that arsenic causes anemia by inhibiting erythropoiesis. However, the impacts of arsenic exposure on human erythropoiesis remain largely unclear. We report here that low-dose arsenic exposure inhibits the erythroid differentiation of human hematopoietic progenitor cells (HPCs). The impacts of arsenic (in the form of arsenite; As3+) on red blood cell (RBC) development was evaluated using a long-term culture of normal human bone marrow CD34+-HPCs stimulated in vitro to undergo erythropoiesis. Over the time course studied, we analyzed the expression of the cell surface antigens CD34, CD71 and CD235a, which are markers commonly used to monitor the progression of HPCs through the stages of erythropoiesis. Simultaneously, we measured hemoglobin content, which is an important criterion used clinically for diagnosing anemia. As compared to control, low-dose As3+ exposure (100 nM and 500 nM) inhibited the expansion of CD34+-HPCs over the time course investigated; decreased the number of committed erythroid progenitors (BFU-E and CFU-E) and erythroblast differentiation in the subsequent stages; and caused a reduction of hemoglobin content. These findings demonstrate that low-dose arsenic exposure impairs human erythropoiesis, likely by combined effects on various stages of RBC formation.


Assuntos
Antígenos CD34/metabolismo , Arsenitos/efeitos adversos , Diferenciação Celular/efeitos dos fármacos , Células Precursoras Eritroides/efeitos dos fármacos , Células-Tronco Hematopoéticas/efeitos dos fármacos , Hemoglobinas/metabolismo , Anemia/induzido quimicamente , Anemia/metabolismo , Antígenos CD/metabolismo , Células Cultivadas , Eritroblastos/efeitos dos fármacos , Eritroblastos/metabolismo , Células Precursoras Eritroides/metabolismo , Eritropoese/efeitos dos fármacos , Glicoforinas/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Humanos , Receptores da Transferrina/metabolismo
19.
Int J Mol Sci ; 22(22)2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34830326

RESUMO

Iron is an essential trace metal for almost all organisms, including human; however, oxidative stress can easily be caused when iron is in excess, producing toxicity to the human body due to its capability to be both an electron donor and an electron acceptor. Although there is a strict regulation mechanism for iron homeostasis in the human body and brain, it is usually inevitably disturbed by genetic and environmental factors, or disordered with aging, which leads to iron metabolism diseases, including many neurodegenerative diseases such as Alzheimer's disease (AD). AD is one of the most common degenerative diseases of the central nervous system (CNS) threatening human health. However, the precise pathogenesis of AD is still unclear, which seriously restricts the design of interventions and treatment drugs based on the pathogenesis of AD. Many studies have observed abnormal iron accumulation in different regions of the AD brain, resulting in cognitive, memory, motor and other nerve damages. Understanding the metabolic balance mechanism of iron in the brain is crucial for the treatment of AD, which would provide new cures for the disease. This paper reviews the recent progress in the relationship between iron and AD from the aspects of iron absorption in intestinal cells, storage and regulation of iron in cells and organs, especially for the regulation of iron homeostasis in the human brain and prospects the future directions for AD treatments.


Assuntos
Doença de Alzheimer/metabolismo , Encéfalo/metabolismo , Homeostase/genética , Sobrecarga de Ferro/metabolismo , Ferro/metabolismo , Macrófagos/metabolismo , Doença de Alzheimer/complicações , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/genética , Peptídeos beta-Amiloides/metabolismo , Antígenos CD/genética , Antígenos CD/metabolismo , Encéfalo/patologia , Proteínas de Transporte de Cátions/genética , Proteínas de Transporte de Cátions/metabolismo , Regulação da Expressão Gênica , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Absorção Intestinal , Sobrecarga de Ferro/complicações , Sobrecarga de Ferro/etiologia , Sobrecarga de Ferro/genética , Fígado/metabolismo , Fígado/patologia , Macrófagos/patologia , Receptores da Transferrina/genética , Receptores da Transferrina/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transferrina/genética , Transferrina/metabolismo , Reação Transfusional/complicações
20.
Cell Rep ; 37(7): 110008, 2021 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-34788623

RESUMO

Clathrin-mediated endocytosis (CME) is critical for cellular signal transduction, receptor recycling, and membrane homeostasis in mammalian cells. Acute depletion of cholesterol disrupts CME, motivating analysis of CME dynamics in the context of human disorders of cholesterol metabolism. We report that inhibition of post-squalene cholesterol biosynthesis impairs CME. Imaging of membrane bending dynamics and the CME pit ultrastructure reveals prolonged clathrin pit lifetimes and shallow clathrin-coated structures, suggesting progressive impairment of curvature generation correlates with diminishing sterol abundance. Sterol structural requirements for efficient CME include 3' polar head group and B-ring conformation, resembling the sterol structural prerequisites for tight lipid packing and polarity. Furthermore, Smith-Lemli-Opitz fibroblasts with low cholesterol abundance exhibit deficits in CME-mediated transferrin internalization. We conclude that sterols lower the energetic costs of membrane bending during pit formation and vesicular scission during CME and suggest that reduced CME activity may contribute to cellular phenotypes observed within disorders of cholesterol metabolism.


Assuntos
Vesículas Revestidas por Clatrina/metabolismo , Endocitose/fisiologia , Esteróis/farmacologia , Extensões da Superfície Celular/metabolismo , Extensões da Superfície Celular/fisiologia , Colesterol/metabolismo , Clatrina/metabolismo , Fibroblastos/metabolismo , Células HEK293 , Humanos , Metabolismo dos Lipídeos/fisiologia , Lipídeos/fisiologia , Proteínas de Membrana/metabolismo , Receptores da Transferrina/metabolismo , Esteróis/metabolismo
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