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1.
PLoS One ; 15(7): e0235904, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32663208

RESUMO

Pancreatic ductal adenocarcinoma is one of the most aggressive types of cancer. Certain proteins in the tumor microenvironment have attracted considerable attention owing to their association with tumor invasion and metastasis. Here, we used proteomics to identify proteins associated with lymph-node metastasis, which is one of the prognostic factors. We selected lymph node metastasis-positive and -negative patients (n = 5 each) who underwent pancreatectomy between 2005 and 2015 and subjected to comprehensive proteomic profiling of tumor stroma. A total of 490 proteins were detected by mass spectrometry. Software analysis revealed that nine of these proteins were differentially expressed between the two patient groups. We focused on hemopexin and ferritin light chain based on immunohistochemistry results. We assessed the clinicopathological data of 163 patients and found that hemopexin expression was associated with UICC N2 (p = 0.0399), lymph node ratio (p = 0.0252), venous invasion (p = 0.0096), and lymphatic invasion (p = 0.0232). Notably, in vitro assays showed that hemopexin promotes invasion of the pancreatic cancer cells. Our findings suggest that hemopexin is a lymph node metastasis-associated protein that could potentially serve as a useful therapeutic target or biomarker of pancreatic ductal adenocarcinoma.


Assuntos
Carcinoma Ductal Pancreático/patologia , Hemopexina/metabolismo , Neoplasias Pancreáticas/patologia , Idoso , Apoferritinas/metabolismo , Carcinoma Ductal Pancreático/metabolismo , Linhagem Celular Tumoral , Movimento Celular , Cromatografia Líquida de Alta Pressão , Feminino , Humanos , Imuno-Histoquímica , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Neoplasias Pancreáticas/metabolismo , Prognóstico , Proteoma/análise , Proteômica/métodos , Espectrometria de Massas em Tandem
2.
Chemistry ; 26(26): 5770-5773, 2020 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-32027764

RESUMO

X-ray structures of homopolymeric human L-ferritin and horse spleen ferritin were solved by freezing protein crystals at different time intervals after exposure to a ferric salt and revealed the growth of an octa-nuclear iron cluster on the inner surface of the protein cage with a key role played by some glutamate residues. An atomic resolution view of how the cluster formation develops starting from a (µ3 -oxo)tris[(µ2 -glutamato-κO:κO')](glutamato-κO)(diaquo)triiron(III) seed is provided. The results support the idea that iron biomineralization in ferritin is a process initiating at the level of the protein surface, capable of contributing coordination bonds and electrostatic guidance.


Assuntos
Apoferritinas/química , Ferritinas/química , Ferro/química , Animais , Apoferritinas/metabolismo , Fenômenos Biológicos , Cavalos , Humanos
3.
Int J Nanomedicine ; 14: 9525-9534, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31824148

RESUMO

Introduction: Advancement of novel anticancer drugs into clinical use is frequently halted by their lack of solubility, reduced stability under physiological conditions, and non-specific uptake by normal tissues, causing systemic toxicity. Their progress to use in the clinic could be accelerated by the development of new formulations employing suitable and complementary drug delivery vehicles. Methods: A robust method for apoferritin (AFt)-encapsulation of antitumour benzothiazoles has been developed for enhanced activity against and drug delivery to benzothiazole-sensitive cancers. Results: More than 70 molecules of benzothiazole 5F 203 were encapsulated per AFt cage. Post-encapsulation, the size and integrity of the protein cages were retained as evidenced by dynamic light scattering. ToF-SIMS depth profiling using an argon cluster beam confirmed 5F 203 exclusively within the AFt cavity. Improved encapsulation of benzothiazole lysyl-amide prodrugs was achieved (~130 molecules of Phortress per AFt cage). Transferrin receptor 1, TfR1, was detected in lysates prepared from most cancer cell lines studied, contributing to enhanced anticancer potency of the AFt-encapsulated benzothiazoles (5F 203, Phortress, GW 610, GW 608-Lys). Nanomolar activity was demonstrated by AFt-formulations in breast, ovarian, renal and gastric carcinoma cell lines, whereas GI50 >50 µM was observed in non-tumourigenic MRC-5 fibroblasts. Intracellular 5F 203, a potent aryl hydrocarbon receptor (AhR) ligand, and inducible expression of cytochrome P450 (CYP) 1A1 were detected following exposure of sensitive cells to AFt-5F 203, confirming that the activity of benzothiazoles was not compromised following encapsulation. Conclusion: Our results show enhanced potency and selectivity of AFt-encapsulated 5F 203 against carcinomas derived from breast, ovarian, renal, colorectal as well as gastric cancer models, and offer realistic prospects for potential refinement of tumour-targeting and treatment, and merit further in vivo investigations.


Assuntos
Antineoplásicos/farmacologia , Apoferritinas/metabolismo , Sistemas de Liberação de Medicamentos , Tiazóis/farmacologia , Linhagem Celular Tumoral , Sistema Enzimático do Citocromo P-450/metabolismo , Feminino , Humanos , Receptores de Hidrocarboneto Arílico/metabolismo , Tiazóis/química
4.
Oxid Med Cell Longev ; 2019: 3461251, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31781333

RESUMO

Reactive oxygen species (ROS) mediates cisplatin-induced cytotoxicity in tumor cells. However, when cisplatin-induced ROS do not reach cytotoxic levels, cancer cells may develop chemoresistance. This phenomenon can be attributed to the inherited high expression of antioxidant protein network. H-Ferritin is an important member of the antioxidant system due to its ability to store iron in a nontoxic form. Altered expression of H-Ferritin has been described in ovarian cancers; however, its functional role in cisplatin-based chemoresistance of this cancer type has never been explored. Here, we investigated whether the modulation of H-Ferritin might affect cisplatin-induced cytotoxicity in ovarian cancer cells. First, we characterized OVCAR3 and OVCAR8 cells for their relative ROS and H-Ferritin baseline amounts. OVCAR3 exhibited lower ROS levels compared to OVCAR8 and greater expression of H-Ferritin. In addition, OVCAR3 showed pronounced growth potential and survival accompanied by the strong activation of pERK/pAKT and overexpression of c-Myc and cyclin E1. When exposed to different concentrations of cisplatin, OVCAR3 were less sensitive than OVCAR8. At the lowest concentration of cisplatin (6 µM), OVCAR8 underwent a consistent apoptosis along with a downregulation of H-Ferritin and a consistent increase of ROS levels; on the other hand, OVCAR3 cells were totally unresponsive, H-Ferritin was almost unaffected, and ROS amounts met a slight increase. Thus, we assessed whether the modulation of H-Ferritin levels was able to affect the cisplatin-mediated cytotoxicity in both the cell lines. H-Ferritin knockdown strengthened cisplatin-mediated ROS increase and significantly restored sensitivity to 6 µM cisplatin in resistant OVCAR3 cells. Conversely, forced overexpression of H-Ferritin significantly suppressed the cisplatin-mediated elevation of intracellular ROS subsequently leading to a reduced responsiveness in OVCAR8 cells. Overall, our findings suggest that H-Ferritin might be a key protein in cisplatin-based chemoresistance and that its inhibition may represent a potential approach for enhancing cisplatin sensitivity of resistant ovarian cancer cells.


Assuntos
Apoferritinas/metabolismo , Cisplatino/farmacologia , Citotoxinas/farmacologia , Resistencia a Medicamentos Antineoplásicos , Proteínas de Neoplasias/metabolismo , Neoplasias Ovarianas/tratamento farmacológico , Espécies Reativas de Oxigênio/metabolismo , Adulto , Idoso , Linhagem Celular Tumoral , Intervalo Livre de Doença , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/mortalidade , Neoplasias Ovarianas/patologia , Taxa de Sobrevida
5.
PLoS Genet ; 15(9): e1008396, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31568497

RESUMO

The interplay between signalling pathways and metabolism is crucial for tissue growth. Yet, it remains poorly understood. Here, we studied the consequences of modulating iron metabolism on the growth of Drosophila imaginal discs. We find that reducing the levels of the ferritin heavy chain in the larval wing discs leads to drastic growth defects, whereas light chain depletion causes only minor defects. Mutant cell clones for the heavy chain lack the ability to compete against Minute mutant cells. Reactive oxygen species (ROS) accumulate in wing discs with reduced heavy chain levels, causing severe mitochondrial defects and ferroptosis. Preventing ROS accumulation alleviates some of the growth defects. We propose that the increased expression of ferritin in hippo mutant cells may protect against ROS accumulation.


Assuntos
Apoferritinas/metabolismo , Ferro/metabolismo , Asas de Animais/metabolismo , Animais , Apoferritinas/fisiologia , Morte Celular , Células Cultivadas , Drosophila/genética , Drosophila/metabolismo , Proteínas de Drosophila/metabolismo , Ferroptose/fisiologia , Discos Imaginais/metabolismo , Mitocôndrias/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Asas de Animais/crescimento & desenvolvimento
6.
Photosynth Res ; 142(2): 169-180, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31522365

RESUMO

Inspired by the bioinorganic structure of natural [FeFe]-hydrogenase ([FeFe]-H2ase) that possesses iron sulfur clusters to catalyze proton reduction to hydrogen (H2), we design a supramolecular photosystem by sequentially integrating hydrophobic ruthenium complex (as a photosensitizer) and diiron dithiolate complex (as a photocatalyst) into the inner surface or cavity of apoferritin via noncovalent interactions. This platform allows photosensitizer and catalyst to localize in a close proximity and short-distance electron transfer process to occur within a confined space. The resulted uniform core-shell nanocomposites were stable and well dispersed in water, and showed enhanced H2 generation activity in acidic solution as compared to the homogenous system without apoferritin participation.


Assuntos
Apoferritinas/metabolismo , Fármacos Fotossensibilizantes/farmacologia , Fotossíntese , Catálise/efeitos dos fármacos , Transporte de Elétrons/efeitos dos fármacos , Hidrogênio/metabolismo , Concentração de Íons de Hidrogênio , Luminescência , Nanocompostos/química , Fotossíntese/efeitos dos fármacos , Rutênio/química , Espectrofotometria Ultravioleta
7.
Arch Insect Biochem Physiol ; 102(1): e21592, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31276235

RESUMO

Ferritin, which is ubiquitous among all living organisms, plays a crucial role in maintaining iron homeostasis, immune response, and detoxification. In the present research, we identified an iron-binding protein, ferritin heavy chain subunit, from Papilio xuthus and named PxFerHCH. The complete complementary DNA of PxFerHCH was 1,252 bp encoding a sequence of 211 amino acids, which includes an iron-responsive element. Phylogenetic analysis showed that PxFerHCH is clustered with Manduca sexta and Galleria mellonella ferritin heavy chain subunits. Expression levels of PxFerHCH in various tissues were analyzed by reverse transcription quantitative polymerase chain reaction, and the results exhibited that PxFerHCH was expressed in all tissues with the highest expression in the fat body. The relative expression level of PxFerHCH in response to bacterial (Escherichia coli and Staphylococcus aureus) challenges sharply increased by about 12 hr postinfection (hpi) and then decreased at 24 hpi. In addition, the iron-binding capacity and antioxidation activity of recombinant PxFerHCH protein were also investigated. These results reveal that PxFerHCH might play an important role in defense against bacterial infection.


Assuntos
Apoferritinas/metabolismo , Borboletas/metabolismo , Ferro/metabolismo , Sequência de Aminoácidos , Animais , Apoferritinas/genética , Apoferritinas/isolamento & purificação , Sequência de Bases , Borboletas/genética , Borboletas/imunologia , Escherichia coli , Proteínas de Insetos/genética , Proteínas de Insetos/metabolismo , Staphylococcus aureus
8.
eNeuro ; 6(4)2019.
Artigo em Inglês | MEDLINE | ID: mdl-31300544

RESUMO

HIV-associated neurocognitive disorders (HAND) remain prevalent and are aggravated by µ-opioid use. We have previously shown that morphine and other µ-opioids may contribute to HAND by inhibiting the homeostatic and neuroprotective chemokine receptor CXCR4 in cortical neurons, and this novel mechanism depends on upregulation of the protein ferritin heavy chain (FHC). Here, we examined the cellular events and potential mechanisms involved in morphine-mediated FHC upregulation using rat cortical neurons of either sex in vitro and in vivo. Morphine dose dependently increased FHC protein levels in primary neurons through µ-opioid receptor (µOR) and Gαi-protein signaling. Cytoplasmic FHC levels were significantly elevated, but nuclear FHC levels and FHC gene expression were unchanged. Morphine-treated rats also displayed increased FHC levels in layer 2/3 neurons of the prefrontal cortex. Importantly, both in vitro and in vivo FHC upregulation was accompanied by loss of mature dendritic spines, which was also dependent on µOR and Gαi-protein signaling. Moreover, morphine upregulated ferritin light chain (FLC), a component of the ferritin iron storage complex, suggesting that morphine altered neuronal iron metabolism. Indeed, prior to FHC upregulation, morphine increased cytoplasmic labile iron levels as a function of decreased endolysosomal iron. In line with this, chelation of endolysosomal iron (but not extracellular iron) blocked morphine-induced FHC upregulation and dendritic spine reduction, whereas iron overloading mimicked the effect of morphine on FHC and dendritic spines. Overall, these data demonstrate that iron mediates morphine-induced FHC upregulation and consequent dendritic spine deficits and implicate endolysosomal iron efflux to the cytoplasm in these effects.


Assuntos
Analgésicos Opioides/administração & dosagem , Apoferritinas/metabolismo , Córtex Cerebral/efeitos dos fármacos , Endossomos/metabolismo , Ferro/metabolismo , Lisossomos/metabolismo , Morfina/administração & dosagem , Neurônios/efeitos dos fármacos , Animais , Córtex Cerebral/metabolismo , Espinhas Dendríticas/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Masculino , Neurônios/citologia , Neurônios/metabolismo , Cultura Primária de Células , Ratos Sprague-Dawley , Receptores Opioides mu/metabolismo , Regulação para Cima
9.
Gene ; 710: 399-405, 2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31200088

RESUMO

Iron-responsive elements (IREs) are ~35-nucleotide (nt) stem-loop RNA structures located in 5' or 3' untranslated regions (UTRs) of mRNAs that mediate post-transcriptional regulation by their association with IRE-binding proteins (IRPs). IREs are characterized by their apical 6-nt loop motif 5'-CAGWGH-3' (W = A or U and H = A, C or U), the so-called pseudotriloop, of which the loop nts C1 and G5 are paired, and the none-paired C between the two stem regions. In this study, the yeast three-hybrid (Y3H) system was used to investigate the relevance of the pseudotriloop structure of ferritin light chain (FTL) for the IRE-IRP interaction and the binding affinities between variant IRE(-like) structures and the two IRP isoforms, IRP1 and 2. Destabilization of the pseudotriloop structure by a G5-to-A mutation reduced binding of IRP1 and 2, while restoring the pseudotriloop conformation by the compensatory C1-to-U mutation, restored binding to both IRPs. In particular, IRP1 showed even stronger binding to the C1U-G5A mutant than to the wildtype FTL IRE. On the other hand, deletion of the bulged-out U6 of the pseudotriloop did not significantly affect its binding to either IRP1 or 2, but substitution with C particularly enhanced the binding to IRP1. In comparison to FTL IRE, IRE-like structures of 5'-aminolevulinate synthase 2 (ALAS2) and SLC40A1 (also known as ferroportin-1) showed similar or, in the case of endothelial PAS domain protein 1 (EPAS1) IRE, slightly weaker binding affinity to IRPs. SLC11A2 (a.k.a. divalent metal transporter-1) IRE exhibited relatively weak binding to IRP1 and medium binding to IRP2. Notably, the IRE-like structure of α-synuclein showed no detectable binding to either IRP under the conditions used in this Y3H assay. Our results indicate that Y3H can be used to characterize binding between IRPs and various IRE-like structures in vivo.


Assuntos
Apoferritinas/química , Apoferritinas/genética , Proteína 1 Reguladora do Ferro/metabolismo , Proteína 2 Reguladora do Ferro/metabolismo , 5-Aminolevulinato Sintetase/química , 5-Aminolevulinato Sintetase/genética , 5-Aminolevulinato Sintetase/metabolismo , Animais , Apoferritinas/metabolismo , Fatores de Transcrição Hélice-Alça-Hélice Básicos/química , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Proteínas de Transporte de Cátions/química , Proteínas de Transporte de Cátions/genética , Proteínas de Transporte de Cátions/metabolismo , Proteína 1 Reguladora do Ferro/genética , Proteína 2 Reguladora do Ferro/genética , Mutação , Conformação de Ácido Nucleico , Técnicas do Sistema de Duplo-Híbrido , Regiões não Traduzidas
10.
Med Sci Monit ; 25: 3700-3715, 2019 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-31104064

RESUMO

BACKGROUND Serum ferritin is a useful tumor marker for renal cell carcinoma (RCC). However, the expression of ferritin heavy chain (FTH1), the main subunit of ferritin, is unclear in primary RCC tissues. In this study, we investigated FTH1 mRNA expression and its diagnostic and prognostic value in RCC. MATERIAL AND METHODS The mRNA expression of FTH1 was analyzed using including Oncomine, Gene Expression Omnibus, and Cancer Genome Atlas datasets, while the protein level of FTH1 was analyzed using the Human Protein Atlas database. The associations between FTH1 and clinicopathologic characteristics and survival time and Cox multivariate survival analysis were analyzed using SPSS 22.0 software. A meta-analysis was performed to assess consistency of FTH1 expression. GO, KEGG, and PPI analyses were used to predict biological functions. RESULTS According to TCGA data, overexpression of FTH1 was detected in 890 RCC tissues (15.2904±0.63157) compared to 129 normal kidney tissues (14.4502±0.51523, p<0.001). Among the clinicopathological characteristics evaluated, patients with increased pathologic T staging, lymph node metastasis, and distant metastasis were significantly associated with higher expression of FTH1. Elevated FTH1 mRNA levels were correlated with worse prognosis of RCC patients. Cox multivariate survival analysis indicated that age, stage, and M stage were predictors of poor prognosis in patients with RCC. CONCLUSIONS Our data suggest that FTH1 expression is an effective prognostic and diagnosis biomarker for RCC.


Assuntos
Carcinoma de Células Renais/metabolismo , Ferritinas/biossíntese , Neoplasias Renais/metabolismo , Adulto , Idoso , Apoferritinas/genética , Apoferritinas/metabolismo , Biomarcadores Tumorais/biossíntese , Biomarcadores Tumorais/genética , Carcinoma de Células Renais/genética , Carcinoma de Células Renais/patologia , Feminino , Ferritinas/genética , Ferritinas/metabolismo , Humanos , Neoplasias Renais/genética , Neoplasias Renais/patologia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Prognóstico , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transcriptoma
11.
Int J Mol Sci ; 20(10)2019 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-31100837

RESUMO

Ferritin is a spherical iron storage protein composed of 24 subunits and an iron core. Using biomimetic mineralization, magnetic iron oxide can be synthesized in the cavity of ferritin to form magnetoferritin (MFt). MFt, also known as a superparamagnetic protein, is a novel magnetic nanomaterial with good biocompatibility and flexibility for biomedical applications. Recently, it has been demonstrated that MFt had tumor targetability and a peroxidase-like catalytic activity. Thus, MFt, with its many unique properties, provides a powerful platform for tumor diagnosis and therapy. In this review, we discuss the biomimetic synthesis and biomedical applications of MFt.


Assuntos
Apoferritinas/metabolismo , Apoferritinas/uso terapêutico , Ferro/metabolismo , Ferro/uso terapêutico , Óxidos/metabolismo , Óxidos/uso terapêutico , Animais , Fenômenos Biomecânicos , Meios de Contraste , Sistemas de Liberação de Medicamentos , Compostos Férricos , Ferritinas , Humanos , Imagem por Ressonância Magnética , Nanopartículas de Magnetita , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Neoplasias/patologia
12.
Biochemistry ; 58(18): 2318-2325, 2019 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-30986045

RESUMO

Neuroferritinopathy is a rare, adult-onset, dominantly inherited movement disorder caused by mutations in the ferritin gene. A ferritin light-chain variant related to neuroferritinopathy, in which alanine 96 is replaced with threonine (A96T), was expressed in Escherichia coli, purified, and characterized. The circular dichroism, analytical ultracentrifugation, and small-angle X-ray scattering studies have shown that both the subunit structure and the assembly of A96T are the same as those of wild-type human ferritin light chain (HuFTL). The iron-incorporation ability was also comparable to that of HuFTL. Although the structural stability against heat, acid, and denaturant was reduced, the structure was sufficiently stable under physiological conditions. The most remarkable defects observed for A96T were a lower refolding efficiency and a stronger propensity to aggregate. The possible relationship between folding deficiency and disease is discussed.


Assuntos
Apoferritinas/química , Ferritinas/química , Distúrbios do Metabolismo do Ferro/metabolismo , Distrofias Neuroaxonais/metabolismo , Agregação Patológica de Proteínas , Dobramento de Proteína , Apoferritinas/genética , Apoferritinas/metabolismo , Dicroísmo Circular , Ferritinas/genética , Ferritinas/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Distúrbios do Metabolismo do Ferro/genética , Distúrbios do Metabolismo do Ferro/patologia , Microscopia Eletrônica de Transmissão , Mutação de Sentido Incorreto , Distrofias Neuroaxonais/genética , Distrofias Neuroaxonais/patologia , Estabilidade Proteica , Espalhamento a Baixo Ângulo , Temperatura , Difração de Raios X
13.
Fertil Steril ; 111(6): 1226-1235.e1, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30922653

RESUMO

OBJECTIVE: To identify the genetic cause of a pedigree with four patients with 46,XY pure gonadal dysgenesis (PGD). DESIGN: Genetic mutation study. SETTING: Academic medical center. PATIENT(S): Four first cousins, from three households of a Chinese pedigree, affected by 46,XY PGD. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): The patients were studied from clinical and genetic perspectives. Whole-genome sequencing was conducted in family members. RESULT(S): Four first cousins in the third generation were affected by 46,XY PGD. A specific familial characteristic was the prevalence of as high as 100% of gonadal tumors in patients. Whole-genome sequencing identified a new ferritin heavy chain-like 17 (FTHL17) mutation, c.GA442_443TT (p.E148L), which has the potential to interfere with protein function and cause 46,XY PGD. Moreover, the location (Xp21.2) of the FTHL17 gene proves that the family is X-linked recessive. In vitro functional study revealed that the perturbation of FTHL17 caused the decrease of protein expression and cell proliferation. CONCLUSION(S): We describe the first 46,XY PGD pedigree that may be attributed to mutations of the FTHL17 gene. We speculated that the FTHL17 gene is involved in the testis-determining pathway and tumorigenesis.


Assuntos
Apoferritinas/genética , Disgenesia Gonadal 46 XY/genética , Mutação , Neoplasias de Tecido Gonadal/genética , Adolescente , Adulto , Apoferritinas/metabolismo , Proliferação de Células , Análise Mutacional de DNA , Feminino , Predisposição Genética para Doença , Disgenesia Gonadal 46 XY/diagnóstico , Disgenesia Gonadal 46 XY/metabolismo , Disgenesia Gonadal 46 XY/cirurgia , Células HEK293 , Hereditariedade , Humanos , Neoplasias de Tecido Gonadal/diagnóstico , Neoplasias de Tecido Gonadal/metabolismo , Neoplasias de Tecido Gonadal/cirurgia , Linhagem , Fenótipo
14.
Proc Natl Acad Sci U S A ; 116(12): 5681-5686, 2019 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-30833408

RESUMO

Malaria, the disease caused by Plasmodium spp. infection, remains a major global cause of morbidity and mortality. Host protection from malaria relies on immune-driven resistance mechanisms that kill Plasmodium However, these mechanisms are not sufficient per se to avoid the development of severe forms of disease. This is accomplished instead via the establishment of disease tolerance to malaria, a defense strategy that does not target Plasmodium directly. Here we demonstrate that the establishment of disease tolerance to malaria relies on a tissue damage-control mechanism that operates specifically in renal proximal tubule epithelial cells (RPTEC). This protective response relies on the induction of heme oxygenase-1 (HMOX1; HO-1) and ferritin H chain (FTH) via a mechanism that involves the transcription-factor nuclear-factor E2-related factor-2 (NRF2). As it accumulates in plasma and urine during the blood stage of Plasmodium infection, labile heme is detoxified in RPTEC by HO-1 and FTH, preventing the development of acute kidney injury, a clinical hallmark of severe malaria.


Assuntos
Heme/metabolismo , Rim/metabolismo , Malária/fisiopatologia , Animais , Apoferritinas/metabolismo , Linhagem Celular , Progressão da Doença , Células Epiteliais/metabolismo , Ferritinas/metabolismo , Ferritinas/fisiologia , Heme Oxigenase-1/metabolismo , Heme Oxigenase-1/fisiologia , Humanos , Tolerância Imunológica/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Fator 2 Relacionado a NF-E2/metabolismo , Fator 2 Relacionado a NF-E2/fisiologia , Plasmodium berghei/metabolismo , Plasmodium berghei/parasitologia , Regulação para Cima
15.
Nat Commun ; 10(1): 1121, 2019 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-30850661

RESUMO

Human transferrin receptor 1 (CD71) guarantees iron supply by endocytosis upon binding of iron-loaded transferrin and ferritin. Arenaviruses and the malaria parasite exploit CD71 for cell invasion and epitopes on CD71 for interaction with transferrin and pathogenic hosts were identified. Here, we provide the molecular basis of the CD71 ectodomain-human ferritin interaction by determining the 3.9 Å resolution single-particle cryo-electron microscopy structure of their complex and by validating our structural findings in a cellular context. The contact surfaces between the heavy-chain ferritin and CD71 largely overlap with arenaviruses and Plasmodium vivax binding regions in the apical part of the receptor ectodomain. Our data account for transferrin-independent binding of ferritin to CD71 and suggest that select pathogens may have adapted to enter cells by mimicking the ferritin access gate.


Assuntos
Antígenos CD/química , Apoferritinas/química , Proteínas de Protozoários/química , Receptores da Transferrina/química , Receptores Virais/química , Transferrina/química , Proteínas do Envelope Viral/química , Antígenos CD/genética , Antígenos CD/metabolismo , Apoferritinas/genética , Apoferritinas/metabolismo , Arenavirus do Novo Mundo/genética , Arenavirus do Novo Mundo/metabolismo , Sítios de Ligação , Clonagem Molecular , Microscopia Crioeletrônica , Escherichia coli/genética , Escherichia coli/metabolismo , Expressão Gênica , Vetores Genéticos/química , Vetores Genéticos/metabolismo , Células HeLa , Proteína da Hemocromatose/química , Proteína da Hemocromatose/genética , Proteína da Hemocromatose/metabolismo , Humanos , Plasmodium vivax/genética , Plasmodium vivax/metabolismo , Ligação Proteica , Conformação Proteica em alfa-Hélice , Conformação Proteica em Folha beta , Domínios e Motivos de Interação entre Proteínas , Proteínas de Protozoários/genética , Proteínas de Protozoários/metabolismo , Receptores da Transferrina/genética , Receptores da Transferrina/metabolismo , Receptores Virais/genética , Receptores Virais/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Especificidade por Substrato , Transferrina/genética , Transferrina/metabolismo , Proteínas do Envelope Viral/genética , Proteínas do Envelope Viral/metabolismo
16.
Biometals ; 32(2): 251-264, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30756217

RESUMO

Rimicaris exoculata (Decapoda: Bresiliidae) is one of the dominant species among hydrothermal vent communities along the Mid-Atlantic Ridge. This shrimp can tolerate high concentrations of heavy metals such as iron, but the mechanisms used for detoxification and utilization of excess metals remain largely unknown. Ferritin is a major iron storage protein in most living organisms. The central heavy subunit of ferritin (H-ferritin) possesses ferroxidase activity and converts iron from Fe2+ to Fe3+, the non-toxic form used for storage. In the present study, the H-ferritin RexFrtH was identified in the hydrothermal vent shrimp R. exoculata, and found to be highly expressed in the gill, the main organ involved in bioaccumulation of metals, at both RNA and protein levels. Accumulation of RexFrtH decreased from efferent to afferent vessels, coinciding with the direction of water flow through the gills. Fe3+ was localized with RexFrtH, and in vitro iron-binding and ferroxidase assays using recombinant RexFrtH confirmed the high affinity for iron. Based on these results, we propose a model of iron metabolism in R. exoculata gills; ferrous iron from ambient hydrothermal water accumulates and is converted and stored in ferric form by RexFrtH as an iron reservoir when needed for metabolism, or excreted as an intermediate to prevent iron overload. The findings expand our understanding of the adaptation strategies used by shrimps inhabiting extreme hydrothermal vents to cope with extremely high heavy metal concentrations.


Assuntos
Apoferritinas/metabolismo , Decápodes/metabolismo , Fontes Hidrotermais , Ferro/metabolismo , Animais
17.
Semin Nephrol ; 39(1): 76-84, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30606409

RESUMO

Iron is required for key aspects of cellular physiology including mitochondrial function and DNA synthesis and repair. However, free iron is an aberration because of its ability to donate electrons, reduce oxygen, and generate reactive oxygen species. Iron-mediated cell injury or ferroptosis is a central player in the pathogenesis of acute kidney injury. There are several homeostatic proteins and pathways that maintain critical balance in iron homeostasis to allow iron's biologic functions yet avoid ferroptosis. Hepcidin serves as the master regulator of iron homeostasis through its ability to regulate ferroportin-mediated iron export and intracellular H-ferritin levels. Hepcidin is a protective molecule in acute kidney injury. Drugs targeting hepcidin, H-ferritin, and ferroptosis pathways hold great promise to prevent or treat kidney injury. In this review we discuss iron homeostasis under physiological and pathologic conditions and highlight its importance in acute kidney injury.


Assuntos
Lesão Renal Aguda/fisiopatologia , Hepcidinas , Homeostase , Ferro/sangue , Rim/metabolismo , Lesão Renal Aguda/sangue , Animais , Apoferritinas/metabolismo , Heme Oxigenase-1/metabolismo , Hepcidinas/uso terapêutico , Hepcidinas/urina , Humanos , Ferro/metabolismo , Rim/fisiologia , Lipocalina-2/metabolismo
18.
Free Radic Biol Med ; 131: 356-369, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30557609

RESUMO

Dihydroartemisinin (DHA) has been shown to be capable of inhibiting cancer growth, whereas it remains largely elusive that the underlying molecular mechanism of DHA induced acute myeloid leukemia (AML) cell death. In the present study, we examined the effects of DHA on the proliferation and ferroptosis of AML cells as well as to elucidate the underlying molecular mechanisms. We found that DHA strongly inhibited the viability of AML cell lines and arrest cell cycle at G0/G1 phase. Further studies found that DHA effectively induced AML cells ferroptosis, which was iron-dependent and accompanied by mitochondrial dysfunction. Mechanistically, DHA induced autophagy by regulating the activity of AMPK/mTOR/p70S6k signaling pathway, which accelerated the degradation of ferritin, increased the labile iron pool, promoted the accumulation of cellular ROS and eventually led to ferroptotic cell death. Over expression of ISCU (Iron-sulfur cluster assembly enzyme, a mitochondrial protein) significantly attenuated DHA induced ferroptosis by regulating iron metabolism, rescuing the mitochondrial function and increasing the level of GSH. Meanwhile, FTH reconstituted AML cells also exhibited the reduced lipid peroxides content and restored the DHA-induced ferroptosis. In summary, these results provide experimental evidences on the detailed mechanism of DHA-induced ferroptosis and reveal that DHA might represent a promising therapeutic agent to preferentially target AML cells.


Assuntos
Antineoplásicos/farmacologia , Apoferritinas/genética , Artemisininas/farmacologia , Ferroptose/efeitos dos fármacos , Regulação Leucêmica da Expressão Gênica , Leucemia Mieloide Aguda/tratamento farmacológico , Proteínas Quinases Ativadas por AMP/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Antimaláricos/farmacologia , Apoferritinas/metabolismo , Autofagia/efeitos dos fármacos , Autofagia/genética , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ferroptose/genética , Células HL-60 , Humanos , Proteínas com Ferro-Enxofre/genética , Proteínas com Ferro-Enxofre/metabolismo , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Camundongos Nus , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Proteólise , Espécies Reativas de Oxigênio/agonistas , Espécies Reativas de Oxigênio/metabolismo , Proteínas Quinases S6 Ribossômicas 70-kDa/genética , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Transdução de Sinais , Células THP-1 , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Clin Sci (Lond) ; 133(1): 135-148, 2019 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-30552136

RESUMO

OBJECTIVE: Ferritin, an iron-binding protein, is ubiquitous and highly conserved; it plays a crucial role in inflammation, which is the main symptom of periodontitis. Full-length cDNA library analyses have demonstrated abundant expression of ferritin in human periodontal ligament. The aims of the present study were to explore how ferritin is regulated by local inflammation, and to investigate its functions and mechanisms of action in the process of periodontitis. METHODS: Human gingival tissues were collected from periodontitis patients and healthy individuals. Experimental periodontitis was induced by ligature of second molars in mice. The expression of ferritin light polypeptide (FTL) and ferritin heavy polypeptide (FTH) were assessed by immunohistochemistry. Meanwhile, after stimulating human periodontal ligament cells (HPDLCs) with P. gingivalis-lipopolysaccharide (LPS), interleukin (IL)-6, and tumor necrosis factor-α (TNF-α), the expression of FTH and FTL were measured. Then, IL-6 and IL-8 were measured after incubation with different concentrations of apoferritin (iron-free ferritin) and several intracellular signaling pathway inhibitors, or after knockdown of the transferrin receptor. RESULTS: Both FTH and FTL were substantially higher in inflamed periodontal tissues than in healthy tissues. The location of the elevated expression correlated well with the extent of inflammatory infiltration. Moreover, expression of FTH and FTL were enhanced after stimulation with P. gingivalis-LPS, IL-6, TNF-α. Apoferritin induced the production of IL-6 and IL-8 in a dose-dependent manner partly through binding to the transferrin receptor and activating ERK/P38 signaling pathways in HPDLCs. CONCLUSIONS: Ferritin is up-regulated by inflammation and exhibits cytokine-like activity in HPDLCs inducing a signaling cascade that promotes expression of pro-inflammatory cytokines associated with periodontitis.


Assuntos
Antígenos CD/metabolismo , Apoferritinas/metabolismo , Citocinas/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Ferritinas/metabolismo , Mediadores da Inflamação/metabolismo , Ligamento Periodontal/enzimologia , Periodontite/enzimologia , Receptores da Transferrina/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Animais , Antígenos CD/genética , Apoferritinas/genética , Estudos de Casos e Controles , Células Cultivadas , Modelos Animais de Doenças , Ferritinas/genética , Humanos , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Ligamento Periodontal/patologia , Periodontite/genética , Periodontite/patologia , Receptores da Transferrina/genética , Transdução de Sinais , Fator de Necrose Tumoral alfa/metabolismo , Regulação para Cima
20.
J Clin Endocrinol Metab ; 104(3): 688-696, 2019 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-30260393

RESUMO

Context: Iron overload has been associated with greater adipose tissue (AT) depots. We retrospectively studied the potential interactions between iron and AT during an experimental overfeeding in participants without obesity. Methods: Twenty-six participants (mean body mass index ± SD, 24.7 ± 3.1 kg/m2) underwent a 56-day overfeeding (+760 kcal/d). Serum iron biomarkers (ELISA), subcutaneous AT (SAT) gene expression, and abdominal AT distribution assessed by MRI were analyzed at the beginning and the end of the intervention. Results: Before intervention: SAT mRNA expression of the iron transporter transferrin (Tf) was positively correlated with the expression of genes related to lipogenesis (lipin 1, ACSL1) and lipid storage (SCD). SAT expression of the ferritin light chain (FTL) gene, encoding ferritin (FT), an intracellular iron storage protein, was negatively correlated to SREBF1, a gene related to lipogenesis. Serum FT (mean, 92 ± 57 ng/mL) was negatively correlated with the expression of SAT genes linked to lipid storage (SCD, DGAT2) and to lipogenesis (SREBF1, ACSL1). After intervention: Overfeeding led to a 2.3 ± 1.3-kg weight gain. In parallel to increased expression of lipid storage-related genes (mitoNEET, SCD, DGAT2, SREBF1), SAT Tf, SLC40A1 (encoding ferroportin 1, a membrane iron export channel) and hephaestin mRNA levels increased, whereas SAT FTL mRNA decreased, suggesting increased AT iron requirement. Serum FT decreased to 67 ± 43 ng/mL. However, no significant associations between serum iron biomarkers and AT distribution or expansion were observed. Conclusion: In healthy men, iron metabolism gene expression in SAT is associated with lipid storage and lipogenesis genes expression and is modulated during a 56-day overfeeding diet.


Assuntos
Adiposidade/fisiologia , Ferro/metabolismo , Lipogênese/fisiologia , Hipernutrição/fisiopatologia , Gordura Subcutânea/metabolismo , Adulto , Apoferritinas/sangue , Apoferritinas/metabolismo , Biomarcadores/sangue , Proteínas de Transporte de Cátions/metabolismo , Regulação da Expressão Gênica/fisiologia , Voluntários Saudáveis , Humanos , Imagem por Ressonância Magnética , Masculino , Proteínas de Membrana/metabolismo , Hipernutrição/etiologia , Estudos Retrospectivos , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Gordura Subcutânea/diagnóstico por imagem , Ganho de Peso/fisiologia , Adulto Jovem
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