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1.
Plant Mol Biol ; 102(3): 323-337, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31900819

RESUMO

KEY MESSAGE: There is a link between PAP/SAL retrograde pathway, ethylene signaling and Fe metabolism in Arabidopsis. Nuclear gene expression is regulated by a diversity of retrograde signals that travel from organelles to the nucleus in a lineal or classical model. One such signal molecule is 3'-phosphoadenisine-5'-phosphate (PAP) and it's in vivo levels are regulated by SAL1/FRY1, a phosphatase enzyme located in chloroplast and mitochondria. This metabolite inhibits the action of a group of exorribonucleases which participate in post-transcriptional gene expression regulation. Transcriptome analysis of Arabidopsis thaliana mutant plants in PAP-SAL1 pathway revealed that the ferritin genes AtFER1, AtFER3, and AtFER4 are up-regulated. In this work we studied Fe metabolism in three different mutants of the PAP/SAL1 retrograde pathway. Mutant plants showed increased Fe accumulation in roots, shoots and seeds when grown in Fe-sufficient condition, and a constitutive activation of the Strategy I Fe uptake genes. As a consequence, they grew more vigorously than wild type plants in Fe-deficient medium. However, when mutant plants grown in Fe-deficient conditions were sprayed with Fe in their leaves, they were unable to deactivate root Fe uptake. Ethylene synthesis inhibition revert the constitutive Fe uptake phenotype. We propose that there is a link between PAP/SAL pathway, ethylene signaling and Fe metabolism.


Assuntos
Difosfato de Adenosina/metabolismo , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Ferro/metabolismo , Monoéster Fosfórico Hidrolases/metabolismo , Transdução de Sinais , Difosfato de Adenosina/genética , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/genética , Clorofila , Cloroplastos/metabolismo , Ferritinas/genética , Ferritinas/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Genes de Plantas/genética , Homeostase , Mitocôndrias/metabolismo , Mutação , Monoéster Fosfórico Hidrolases/genética , Folhas de Planta/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo
2.
Inorg Chem ; 59(1): 629-641, 2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31820939

RESUMO

Ferritins are supramolecular nanocage proteins, which synthesize hydrated ferric oxyhydroxide mineral via protein mediated rapid Fe2+ sequestration and ferroxidase reactions. Ferritin minerals are also associated with a significant amount of phosphate, which contribute toward their structure and reactivity. Like iron, phosphate also regulates the pathogenesis of Mycobacterium tuberculosis (Mtb), which expresses two types of ferritin: heme binding bacterioferritin A (BfrA) and nonheme binding bacterioferritin B (BfrB). Unlike Mtb BfrA, the rapid kinetics and mechanism of ferroxidase activity, and the mineral core formation/dissolution in Mtb BfrB are not well explored. Moreover, the effect of physiological levels of phosphate (0-10 mM) on the synthesis, structure, and reactivity of ferritin mineral core also require investigation in detail. Therefore, the stopped-flow rapid kinetics of ferroxidase activity (ΔA650/Δt) of Mtb BfrB was carried out, which detected a transient intermediate similar to diferric peroxo species as observed in frog and human ferritins. Increasing phosphate concentration increased the initial rate of iron mineralization (ΔA350/Δt) and dissolved O2 consumption (both ∼1.5-2-fold). Phosphate not only decreased the amount of iron loading and size of the BfrB mineral core (both up to 2-fold) but also decreased its crystallinity, resembling the variations observed in the core morphology of different native ferritins. In addition, phosphate inhibited the kinetics of reductive iron mobilization (∼6-8-fold) indicating its influence on the stability of the iron mineral core. Hence, the current work provides the kinetic/mechanistic insight toward the ferroxidase activity in Mtb BfrB, apart from demonstrating the role of phosphate toward the structure/reactivity of its iron mineral.


Assuntos
Proteínas de Bactérias/metabolismo , Grupo dos Citocromos b/metabolismo , Ferritinas/metabolismo , Ferro/metabolismo , Mycobacterium tuberculosis/química , Fosfatos/metabolismo , Animais , Anuros , Proteínas de Bactérias/química , Proteínas de Bactérias/isolamento & purificação , Grupo dos Citocromos b/química , Grupo dos Citocromos b/isolamento & purificação , Ferritinas/química , Ferritinas/isolamento & purificação , Humanos , Ferro/química , Cinética , Mycobacterium tuberculosis/metabolismo , Fosfatos/química
3.
Adv Exp Med Biol ; 1174: 313-329, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31713204

RESUMO

Protein cages are normally formed by the self-assembly of multiple protein subunits and ferritin is a typical example of a protein cage structure. Ferritin is a ubiquitous multi-subunit iron storage protein formed by 24 polypeptide chains that self-assemble into a hollow, roughly spherical protein cage. Ferritin has external and internal diameters of approximately 12 nm and 8 nm, respectively. Functionally, ferritin performs iron sequestration and is highly conserved in evolution. The interior cavity of ferritin provides a unique reaction vessel to carry out reactions separated from the exterior environment. In nature, the cavity is utilized for sequestration of iron and bio-mineralization as a mechanism to render iron inert and safe from the external environment. Material scientists have been inspired by this system and exploited a range of ferritin superfamily proteins as supramolecular templates to encapsulate different carrier molecules ranging from cancer drugs to therapeutic proteins, in addition to using ferritin proteins as well-defined building blocks for fabrication. Besides the interior cavity, the exterior surface and sub-unit interface of ferritin can be modified without affecting ferritin assembly.


Assuntos
Ferritinas , Nanotecnologia , Ferritinas/química , Ferritinas/metabolismo , Ferro/química , Nanotecnologia/tendências , Relação Estrutura-Atividade
4.
Invest Ophthalmol Vis Sci ; 60(13): 4378-4387, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31634395

RESUMO

Purpose: Iron supplementation therapy is used for iron-deficiency anemia but has been associated with macular degeneration in a 43-year-old patient. Iron entry into the neurosensory retina (NSR) can be toxic. It is important to determine conditions under which serum iron might cross the blood retinal barrier (BRB) into the NSR. Herein, an established mouse model of systemic iron overload using high-dose intraperitoneal iron dextran (IP FeDex) was studied. In addition, because the NSR expresses the iron regulatory hormone hepcidin, which could limit iron influx into the NSR, we gave retina-specific hepcidin knockout (RS-HepcKO) mice IP FeDex to test this possibility. Methods: Wild-type (WT) and RS-HepcKO mice were given IP FeDex. In vivo retina imaging was performed. Blood and tissues were analyzed for iron levels. Quantitative PCR was used to measure levels of mRNAs encoding iron regulatory and photoreceptor-specific genes. Ferritin and albumin were localized in the retina by immunofluorescence. Results: IP FeDex in both WT and RS-HepcKO mice induced high levels of iron in the liver, serum, retinal vascular endothelial cells (rVECs), and RPE, but not the NSR. The BRB remained intact. Retinal degeneration did not occur. Conclusions: Following injection of high-dose IP FeDex, iron accumulated in the BRB, but not the NSR. Thus, the BRB can shield the NSR from iron delivered in this manner. This ability is not dependent on NSR hepcidin production.


Assuntos
Barreira Hematorretiniana/metabolismo , Células Endoteliais/metabolismo , Sobrecarga de Ferro/metabolismo , Complexo Ferro-Dextran/administração & dosagem , Ferro/metabolismo , Vasos Retinianos/metabolismo , Albuminas/metabolismo , Animais , Modelos Animais de Doenças , Ferritinas/metabolismo , Técnica Indireta de Fluorescência para Anticorpo , Hepcidinas/farmacologia , Injeções Intraperitoneais , Fígado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Transferrina/metabolismo
5.
J Insect Sci ; 19(5)2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31606748

RESUMO

Dengue, yellow fever, and Zika are viruses transmitted by yellow fever mosquito, Aedes aegypti [Linnaeus (Diptera: Culicidae)], to thousands of people each year. Mosquitoes transmit these viruses while consuming a blood meal that is required for oogenesis. Iron, an essential nutrient from the blood meal, is required for egg development. Mosquitoes receive a high iron load in the meal; although iron can be toxic, these animals have developed mechanisms for dealing with this load. Our previous research has shown iron from the blood meal is absorbed in the gut and transported by ferritin, the main iron transport and storage protein, to the ovaries. We now report the distribution of iron and ferritin in ovarian tissues before blood feeding and 24 and 72 h post-blood meal. Ovarian iron is observed in specific locations. Timing post-blood feeding influences the location and distribution of the ferritin heavy-chain homolog, light-chain homolog 1, and light-chain homolog 2 in ovaries. Understanding iron deposition in ovarian tissues is important to the potential use of interference in iron metabolism as a vector control strategy for reducing mosquito fecundity, decreasing mosquito populations, and thereby reducing transmission rates of vector-borne diseases.


Assuntos
Aedes/metabolismo , Ferritinas/metabolismo , Ferro/metabolismo , Ovário/metabolismo , Animais , Sangue/metabolismo , Feminino , Ferritinas/química , Suínos
6.
Sheng Li Xue Bao ; 71(5): 689-697, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31646322

RESUMO

The aim of the present study was to investigate the role of ferroptosis in acute lung injury (ALI) mouse model induced by oleic acid (OA). ALI was induced in the mice via the lateral tail vein injection of pure OA. The histopathological score of lung, lung wet-dry weight ratio and the protein content of bronchoalveolar lavage fluid (BALF) were used as the evaluation indexes of ALI. Iron concentration, glutathione (GSH) and malondialdehyde (MDA) contents in the lung tissues were measured using corresponding assay kits. The ultrastructure of pulmonary cells was observed by transmission electron microscope (TEM), and the expression level of prostaglandin-endoperoxide synthase 2 (PTGS2) mRNA was detected by quantitative polymerase chain reaction (q-PCR). Protein expression levels of glutathione peroxidase 4 (GPX4), ferritin and transferrin receptor 1 (TfR1) in lung tissues were determined by Western blot. The results showed that histopathological scores of lung tissues, lung wet-dry weight ratio and protein in BALF in the OA group were higher than those of the control group. In the OA group, the mitochondria of pulmonary cells were shrunken, and the mitochondrial membrane was ruptured. The expression level of PTGS2 mRNA in the OA group was seven folds over that in the control group. Iron overload, GSH depletion and accumulation of MDA were observed in the OA group. Compared with the control group, the protein expression levels of GPX4 and ferritin in lung tissue were down-regulated in the OA group. These results suggest that ferroptosis plays a potential role in the pathogenesis of ALI in our mouse model, which may provide new insights for development of new drugs for ALI.


Assuntos
Lesão Pulmonar Aguda/patologia , Apoptose , Ácido Oleico , Lesão Pulmonar Aguda/induzido quimicamente , Animais , Líquido da Lavagem Broncoalveolar/química , Ciclo-Oxigenase 2/metabolismo , Ferritinas/metabolismo , Glutationa/análise , Glutationa Peroxidase/metabolismo , Ferro/análise , Sobrecarga de Ferro/fisiopatologia , Pulmão/citologia , Pulmão/patologia , Malondialdeído/análise , Camundongos , Microscopia Eletrônica de Transmissão , Membranas Mitocondriais/ultraestrutura
7.
Complement Ther Med ; 46: 24-28, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31519283

RESUMO

OBJECTIVES: The aim of this study was to determine whether quercetin can reduce iron overload and inflammation in thalassemic patients. METHODS: Eighty four patients were recruited to this study and randomly assigned to two groups: 42 patients received a 500 mg/day quercetin tablet and 42 others took a 500 mg/day starch placebo for 12 weeks. Demographic, anthropometric and biochemical evaluation were performed. RESULTS: ANCOVA analysis revealed that compared to the control group, quercetin could reduce high sensitivity C-reactive protein (hs-CRP) (P = 0.046), iron (p = 0.036), ferritin (p = 0.043), and transferrin saturation (TS) (p = 0.008) and increase transferrin (p = 0.045) significantly, but it had no significant effect on total iron binding capacity (TIBC) (p = 0.734) and tumor necrosis factor α (TNF-α) (p = 0.310). CONCLUSIONS: Quercetin could ameliorate the iron status in thalassemia major, but its effect on inflammation is indistinctive.


Assuntos
Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Sobrecarga de Ferro/tratamento farmacológico , Ferro/efeitos adversos , Ferro/uso terapêutico , Quercetina/uso terapêutico , Talassemia beta/tratamento farmacológico , Adulto , Proteína C-Reativa/metabolismo , Método Duplo-Cego , Feminino , Ferritinas/metabolismo , Humanos , Inflamação/metabolismo , Sobrecarga de Ferro/induzido quimicamente , Sobrecarga de Ferro/metabolismo , Masculino , Transferrina/metabolismo , Talassemia beta/metabolismo
8.
Eur J Histochem ; 63(3)2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31505926

RESUMO

Ferritin, an iron-binding protein, is composed of two subunits, a heavy chain and a light chain. It regulates many biological functions, such as proliferation, angiogenesis, and immunosuppression. The objective of this study was to determine the expression and distribution of ferritin in the periodontal tissuesof primates.First, we assessed the expression of ferritin in primary cultured cells isolated from human periodontal tissues using the polymerase chain reaction and immunofluorescent staining. Second, we investigated the expression and distribution of ferritin in the periodontal tissues of Macaca fascicularis, human gingival tissues, and human gingival carcinoma tissues using immunohistochemistry.Both protein and mRNA of ferritin were constitutively present in human primary cultured cells, including those from the dental apical papilla, periodontal ligament, dental pulp, and gingival epithelium, as well as gingival fibroblasts. In M. fascicularistissues, the immunohistochemical staining was particularly strong in blood vessel and mineralizing areas of the dental pulp and periodontal ligament. Ferritin heavy chain exhibited specific immunopositivity in in the stratum basale of the epithelium in human gingival tissue and strong immunostaining was found in peripheral regions of gingival carcinoma sites. Ferritin is constitutivelypresent andwidelydistributed in the periodontal tissues of primates. Ferritin may play roles in epithelial proliferation, vascular angiogenesis, and mineralization in these tissues.


Assuntos
Ferritinas/metabolismo , Periodonto/metabolismo , Animais , Células Cultivadas , Gengiva/metabolismo , Neoplasias Gengivais/metabolismo , Humanos , Macaca fascicularis , Masculino , Periodonto/citologia
9.
Food Chem ; 301: 125292, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31394334

RESUMO

It is estimated that over 30% of the global population is anaemic, half of which is due to iron deficiency. The bioavailability of iron from vegetables is low and variable, and influenced by food composition and matrix. We have therefore determined the relative bioavailability of iron in five types of green vegetable, spinach, broccoli, savoy cabbage, curly kale and green pepper, by measuring the ferritin response in a simulated digestion/Caco-2 cell model. Savoy cabbage gave the highest ferritin response and analysis of the digest showed that the iron was present in low molecular weight fractions which contained glucose, fructose, organic acids and amino acids. The addition of fructose 1,6-biphosphate to the Caco-2 cells increased iron uptake 2-fold. These results demonstrate that cabbage was the best source of bioavailable iron out of the vegetables studied and suggest that the formation of complexes with fructose derivatives contribute to increase the iron bioavailability.


Assuntos
Ferro/farmacocinética , Verduras/química , Disponibilidade Biológica , Células CACO-2 , Digestão , Ferritinas/metabolismo , Humanos , Ferro/análise , Peso Molecular , Verduras/metabolismo
10.
Elife ; 82019 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-31373554

RESUMO

The palette of tools for perturbation of neural activity is continually expanding. On the forefront of this expansion is magnetogenetics, where ion channels are genetically engineered to be closely coupled to the iron-storage protein ferritin. Initial reports on magnetogenetics have sparked a vigorous debate on the plausibility of physical mechanisms of ion channel activation by means of external magnetic fields. The criticism leveled against magnetogenetics as being physically implausible is based on the specific assumptions about the magnetic spin configurations of iron in ferritin. I consider here a wider range of possible spin configurations of iron in ferritin and the consequences these might have in magnetogenetics. I propose several new magneto-mechanical and magneto-thermal mechanisms of ion channel activation that may clarify some of the mysteries that presently challenge our understanding of the reported biological experiments. Finally, I present some additional puzzles that will require further theoretical and experimental investigation.


Assuntos
Ativação Enzimática/efeitos da radiação , Ferritinas/metabolismo , Canais Iônicos/metabolismo , Campos Magnéticos , Proteínas Recombinantes/metabolismo , Temperatura Ambiente , Ferritinas/genética , Canais Iônicos/genética , Biologia Molecular/métodos , Engenharia de Proteínas/métodos , Proteínas Recombinantes/genética
11.
Nutrients ; 11(8)2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31374868

RESUMO

The common dry bean (Phaseolus vulgaris L.) is a globally produced pulse crop and an important source of micronutrients for millions of people across Latin America and Africa. Many of the preferred black and red seed types in these regions have seed coat polyphenols that inhibit the absorption of iron. Yellow beans are distinct from other market classes because they accumulate the antioxidant kaempferol 3-glucoside in their seed coats. Due to their fast cooking tendencies, yellow beans are often marketed at premium prices in the same geographical regions where dietary iron deficiency is a major health concern. Hence, this study compared the iron bioavailability of three faster cooking yellow beans with contrasting seed coat colors from Africa (Manteca, Amarillo, and Njano) to slower cooking white and red kidney commercial varieties. Iron status and iron bioavailability was assessed by the capacity of a bean based diet to generate and maintain total body hemoglobin iron (Hb-Fe) during a 6 week in vivo (Gallus gallus) feeding trial. Over the course of the experiment, animals fed yellow bean diets had significantly (p ≤ 0.05) higher Hb-Fe than animals fed the white or red kidney bean diet. This study shows that the Manteca yellow bean possess a rare combination of biochemical traits that result in faster cooking times and improved iron bioavailability. The Manteca yellow bean is worthy of germplasm enhancement to address iron deficiency in regions where beans are consumed as a dietary staple.


Assuntos
Ração Animal , Galinhas/sangue , Culinária , Hemoglobinas/metabolismo , Ferro na Dieta/sangue , Ferro na Dieta/metabolismo , Valor Nutritivo , Phaseolus/metabolismo , Sementes/metabolismo , Animais , Disponibilidade Biológica , Células CACO-2 , Proteínas de Transporte de Cátions/metabolismo , Galinhas/crescimento & desenvolvimento , Ferritinas/metabolismo , Temperatura Alta , Humanos , Absorção Intestinal , Mucosa Intestinal/metabolismo , Fatores de Tempo , Ganho de Peso
12.
BMC Genomics ; 20(1): 682, 2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31464583

RESUMO

BACKGROUND: The brown plant hopper (BPH), Nilaparvata lugens, is one of the major pest of rice (Oryza sativa). Plant defenses against insect herbivores have been extensively studied, but our understanding of insect responses to host plants' resistance mechanisms is still limited. The purpose of this study is to characterize transcripts of BPH and reveal the responses of BPH insects to resistant rice at transcription level by using the advanced molecular techniques, the next-generation sequencing (NGS) and the single-molecule, real-time (SMRT) sequencing. RESULTS: The current study obtained 24,891 collapsed isoforms of full-length transcripts, and 20,662 were mapped to known annotated genes, including 17,175 novel transcripts. The current study also identified 915 fusion genes, 1794 novel genes, 2435 long non-coding RNAs (lncRNAs), and 20,356 alternative splicing events. Moreover, analysis of differentially expressed genes (DEGs) revealed that genes involved in metabolic and cell proliferation processes were significantly enriched in up-regulated and down-regulated sets, respectively, in BPH fed on resistant rice relative to BPH fed on susceptible wild type rice. Furthermore, the FoxO signaling pathway was involved and genes related to BPH starvation response (Nlbmm), apoptosis and autophagy (caspase 8, ATG13, BNIP3 and IAP), active oxygen elimination (catalase, MSR, ferritin) and detoxification (GST, CarE) were up-regulated in BPH responses to resistant rice. CONCLUSIONS: The current study provides the first demonstrations of the full diversity and complexity of the BPH transcriptome, and indicates that BPH responses to rice resistance, might be related to starvation stress responses, nutrient transformation, oxidative decomposition, and detoxification. The current result findings will facilitate further exploration of molecular mechanisms of interaction between BPH insects and host rice.


Assuntos
Hemípteros/genética , Oryza/genética , Animais , Proteínas Relacionadas à Autofagia/metabolismo , Caspase 8/metabolismo , Catalase/metabolismo , Feminino , Ferritinas/metabolismo , Proteína Forkhead Box O1/metabolismo , Regulação da Expressão Gênica , Genótipo , Glutationa Transferase/metabolismo , Hemípteros/metabolismo , Herbivoria , Oryza/metabolismo , RNA Longo não Codificante/metabolismo , Transdução de Sinais , Transaminases/metabolismo , Transcriptoma
13.
Adv Exp Med Biol ; 1173: 21-32, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31456203

RESUMO

Iron is an essential trace element in the human body, but excess iron is toxic as it contributes to oxidative damage. To keep iron concentration within the optimal physiologic range, iron metabolism at the cellular level and the whole systemic level are tightly regulated. Balance of iron homeostasis depends on the expression levels and activities of iron carriers, iron transporters, and iron regulatory and storage proteins. Divalent metal transporter 1 (DMT1) at the apical membrane of intestinal enterocyte brings in non-heme iron from the diet, whereas ferroportin 1 (FPN1) at the basal membrane exports iron into the circulation. Plasma transferrin (Tf) then carries iron to various tissues and cells. After binding to transferrin receptor 1 (TfR1), the complex is endocytosed into the cell, where iron enters the cytoplasm via DMT1 on the endosomal membrane. Free iron is either utilized in metabolic processes, such as synthesis of hemoglobin and Fe-S cluster, or sequestered in the cytosolic ferritin, serving as a cellular iron store. Excess iron can be exported from the cell via FPN1. The liver-derived peptide hepcidin plays a major regulatory role in controlling FPN1 level in the enterocyte, and thus controls the whole-body iron absorption. Inside the cells, iron regulatory proteins (IRPs) modulate the expressions of DMT1, TfR1, ferritin, and FPN1 via binding to the iron-responsive element (IRE) in their mRNAs. Both the release of hepcidin and the IRP-IRE interaction are coordinated with the fluctuation of the cellular iron level. Therefore, an adequate and steady iron supplement is warranted for the utilization of cells around the body. Investigations on the molecular mechanisms of cellular iron metabolism and regulation could advance the fields of iron physiology and pathophysiology.


Assuntos
Ferro/metabolismo , Proteínas de Transporte de Cátions/metabolismo , Enterócitos/metabolismo , Ferritinas/metabolismo , Homeostase , Humanos , Sobrecarga de Ferro , Receptores da Transferrina/metabolismo , Fatores de Transcrição/metabolismo , Transferrina/metabolismo
14.
Oxid Med Cell Longev ; 2019: 8753413, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31320987

RESUMO

Epithelial-mesenchymal transition (EMT) contributes to metastasis and drug resistance; inhibition of EMT may attenuate metastasis and drug resistance. It has been demonstrated that ferritinophagy involves the process of many diseases; however, the relationship between EMT and ferritinophagy was not fully established. Some iron chelators show the ability to inhibit EMT, but whether ferritinophagy plays a role in EMT is largely unknown. To this end, we investigated the effect of a novel iron chelator, DpdtpA (2,2 '-di-pyridylketone dithiocarbamate propionic acid), on EMT in the CT26 cell line. The DpdtpA displayed excellent antitumor (IC50 = 1.5 ± 0.2 µM), leading to ROS production and apoptosis occurrence. Moreover, the ROS production correlated with ferritin degradation. The upregulation of LC3-II and NCOA4 from immunofluorescence and Western blotting analysis revealed that the occurrence of ferritinophagy contributed to ROS production. Furthermore, DpdtpA could induce an alteration both in morphology and in epithelial-mesenchymal markers, displaying significant EMT inhibition. The correlation analysis revealed that DpdtpA-induced ferritinophagy contributed to the EMT inhibition, implying that NCOA4 involved EMT process, which was firstly reported. To reinforce this concept, the ferritinophagic flux (NCOA4/ferritin) in either treated by TGF-ß1 or combined with DpdtpA was determined. The results indicated that activating ferritinophagic flux would enhance ROS production which accordingly suppressed EMT or implementing the EMT suppression seemed to be through "fighting fire with fire" strategy. Taken together, our data demonstrated that ferritinophagic flux was a dominating driving force in EMT proceeding, and the new finding definitely will enrich our knowledge of ferritinophagy in EMT process.


Assuntos
Ferritinas/metabolismo , Quelantes de Ferro/uso terapêutico , Transição Epitelial-Mesenquimal , Humanos , Quelantes de Ferro/farmacologia
15.
Folia Med (Plovdiv) ; 61(2): 223-230, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31301666

RESUMO

AIM: Iron deficiency anemia (IDA) is a common medical condition, yet there is still some diagnostic uncertainty in this respect. The aim of this study was to compare the clinical significance of biomarkers of iron deficiency (ID) in diagnosing IDA and iron-deficient erythropoiesis in anemic patients. MATERIALS AND METHODS: A total of 103 untreated patients with non-hemolytic anemia were included. Blood count, reticulocyte hemoglobin content (CHr), iron, transferrin saturation (TSAT), ferritin (Ferr), soluble transferrin receptor (sTfR) and sTfR/logFerr index (sTfR-F index) were determined in the patients. RESULTS: TSAT<16% diagnosed 79 patients with IDA (76.6%), Ferr<30 µg/l - 50 patients with IDA (48.5%). Thomas-plot analysis found 76 patients with ID (73.8%) and 56 of them were with iron-restricted erythropoiesis and IDA (54.4%). Biomarkers of ID were significantly different in anemic patients with iron-deficient erythropoiesis (CHr<28 pg) compared with patients with normal hemoglobinisation (p<0.001). With regard to the predictive value of the parameters of ID for iron-deficient erythropoiesis in anemia, their mutually controlled influence proved sTfR-F index only as independent statistically significant (p=0.011). The optimal cut-off value of sTfR-F index from the ROC curve analysis for detecting iron-deficient erythropoiesis in anemia (CHr<28 pg) was 1.35, with sensitivity of 82.1% and specificity of 80.9% (AUC 0.866; p<0.001). CONCLUSIONS: Diagnosis of IDA depends on the applied biomarkers of ID, and TSAT or ferritin when used alone may lead to diagnostic difficulties. Combining sTfR-F index and CHr to evaluate iron-deficient erythropoiesis in patients with anemia in addition to ferritin and TSAT could contribute to improving the diagnosis of IDA in clinical practice.


Assuntos
Anemia Ferropriva/diagnóstico , Ferritinas/metabolismo , Hemoglobinas/metabolismo , Ferro/metabolismo , Receptores da Transferrina/metabolismo , Reticulócitos/metabolismo , Transferrina/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Anemia Ferropriva/metabolismo , Biomarcadores/metabolismo , Eritropoese , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
16.
Exp Eye Res ; 187: 107728, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31323276

RESUMO

Retinal iron accumulation has been implicated in the pathogenesis of age-related macular degeneration (AMD) and other neurodegenerative diseases. The retina and the brain are protected from the systemic circulation by the blood retinal barrier (BRB) and blood brain barrier (BBB), respectively. Iron levels within the retina and brain need to be tightly regulated to prevent oxidative injury. The method of iron entry through the retina and brain vascular endothelial cells (r&bVECs), an essential component of the BRB and BBB, is not fully understood. However, localization of the cellular iron exporter, ferroportin (Fpn), to the abluminal membrane of these cells, leads to the hypothesis that Fpn may play an important role in the import of iron across the BRB and BBB. To test this hypothesis, a mouse model with deletion of Fpn within the VECs in both the retina and the brain was developed through tail vein injection of AAV9-Ple261(CLDN5)-icre to both experimental Fpnf/f, and control Fpn+/+ mice at P21. Mice were aged to 9 mo and changes in retinal and brain iron distribution were observed. In vivo fundus imaging and quantitative serum iron detection were used for model validation. Eyes and brains were collected for immunofluorescence. Deletion of Fpn from the retinal and brain VECs leads to ferritin-L accumulation, an indicator of elevated iron levels, in the retinal and brain VECs. This occurred despite lower serum iron levels in the experimental mice. This result suggests that Fpn normally transfers iron from retinal and brain VECs into the retina and brain. These results help to better define the method of retina and brain iron import and will increase understanding of neurodegenerative diseases involving iron accumulation.


Assuntos
Proteínas de Transporte de Cátions/metabolismo , Circulação Cerebrovascular/fisiologia , Células Endoteliais/metabolismo , Ferritinas/metabolismo , Vasos Retinianos/metabolismo , Animais , Transporte Biológico , Barreira Hematoencefálica , Barreira Hematorretiniana , Claudina-5/genética , Dependovirus/genética , Técnica Indireta de Fluorescência para Anticorpo , Ferro/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos , Reação em Cadeia da Polimerase em Tempo Real
17.
Adv Pharmacol ; 84: 123-145, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31229168

RESUMO

Iron transport to the brain is a critically important and highly regulated process necessary for proper brain function. This review aims to summarize iron uptake mechanisms in the brain and the importance of sex and genotype on this uptake. In restless legs syndrome (RLS), brain iron uptake has been hypothesized to be dysregulated, leading to the clinically observed brain iron deficiency, so this review specifically comments on this disorder. The review covers transferrin-bound transport and the more recently discovered role of ferritin in brain iron delivery. Studies on the impact of sex, MEIS1 (associated with RLS), and H63D gene variants have revealed critical regulatory mechanisms and driving factors that significantly impact iron transport that may considerably affect the clinical treatment of RLS. RLS has provided insights into the gaps in knowledge underlying brain iron uptake mechanisms and their regulation, which in turn have provided insights into the pathophysiology of RLS.


Assuntos
Barreira Hematoencefálica/metabolismo , Ferro/metabolismo , Caracteres Sexuais , Feminino , Ferritinas/metabolismo , Genótipo , Humanos , Masculino , Síndrome das Pernas Inquietas/genética
18.
Biochim Biophys Acta Mol Cell Res ; 1866(9): 1487-1497, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31229649

RESUMO

Drosophila ZIP13 (dZIP13, CG7816/ZIP99C) belongs to the SLC39A family and is connected to iron homeostasis in the fruit fly. In this study, we show that dZIP13 level is strongly regulated by iron. In addition to a mild response to iron at the mRNA level, dZIP13 is strongly regulated at the protein level. This posttranslational regulation by iron also happens when dZIP13 is expressed in the yeast Saccharomyces cerevisiae. Iron functions to stabilize dZIP13. Domain-swapping experiments between dZIP7 (CG10449/ Catsup) and dZIP13 suggest that the N-terminus of dZIP13 is necessary to mediate this iron regulatory process. Phylogenetic sequence comparison and structural modeling reveal potential iron-binding residues, confirmed by in vitro iron binding assays. Mutations of these potential iron binding sites at the N-terminus, as well as a likely iron binding site at the C-terminus of dZIP13, completely abolish the iron-dependent upregulation in the yeast and the fruit fly. Iron-responsiveness of dZIP13 is consistent with its key role in iron homeostasis. We speculate that this process of dZIP13 regulation, and that of IRE/IRP-controlled ferritin production, work together to better cope with iron repletion in the fly.


Assuntos
Proteínas de Transporte de Cátions/metabolismo , Proteínas de Drosophila/metabolismo , Ferro/metabolismo , Animais , Animais Geneticamente Modificados , Sítios de Ligação , Proteínas de Transporte de Cátions/genética , Drosophila , Proteínas de Drosophila/genética , Ferritinas/metabolismo , Homeostase , Proteínas de Ligação ao Ferro/metabolismo , Modelos Moleculares , Filogenia , RNA Mensageiro , Saccharomyces cerevisiae/genética , Análise de Sequência de Proteína , Regulação para Cima
19.
Toxicol Lett ; 313: 50-59, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31238089

RESUMO

Iron overload causes osteoporosis by enhancing osteoclastic bone resorption. During differentiation, osteoclasts demand high energy and contain abundant mitochondria. In mitochondria, iron is used for the synthesis of Fe-S clusters to support mitochondria biogenesis and electron transport chain. Moreover, mitochondrial reactive oxygen species (ROS) play an important role in osteoclastogenesis. Activation of MAPKs (ERK1/2, JNK, and p38) by ROS is essential and contribute to osteoclast differentiation. How iron chelation impairs electron transport chain and ROS dependent MAPKs activation during osteoclast differentiation is unknown. This study aimed to determine the direct effects of iron chelation on osteoclast differentiation, electron transport chain and MAPKs activation. In the present study, we found that when iron chelator, deferoxamine (DFO), was added, a dose-dependent inhibition of osteoclast differentiation and bone resorption was observed. Supplementation of transferrin-bound iron recovered osteoclastogenesis. Iron chelation resulted in a marked decrease in ferritin level, and increased expression of transferrin receptor 1 and ferroportin. As an iron chelator, DFO negatively affected mitochondrial function through decreasing activities of all the complexes. Expressions of mitochondrial subunits encoded both by mitochondrial and nuclear DNA were decreased. DFO augmented production of mitochondrial ROS, but inhibited the phosphorylation of ERK1/2, JNK, and p38, even in the presence of hydrogen peroxide. These results suggest that iron chelation directly inhibits iron-uptake stimulated osteoclast differentiation and suppresses electron transport chain. Iron chelation negatively regulates MAPKs activation, and this negative regulation is independent on ROS stimulation.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Desferroxamina/farmacologia , Complexo de Proteínas da Cadeia de Transporte de Elétrons/metabolismo , Quelantes de Ferro/farmacologia , Ferro/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Osteoclastos/efeitos dos fármacos , Animais , Reabsorção Óssea , Proteínas de Transporte de Cátions/metabolismo , Células Cultivadas , Relação Dose-Resposta a Droga , Ferritinas/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Osteoclastos/enzimologia , Fosforilação , Espécies Reativas de Oxigênio/metabolismo , Receptores da Transferrina/metabolismo , Transdução de Sinais/efeitos dos fármacos
20.
Chem Commun (Camb) ; 55(52): 7510-7513, 2019 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-31187817

RESUMO

Self-assembly of protein nanocages into two-dimensional superlattices can be achieved by disulfide-mediated modular interactions, which can be carried out by introducing single point mutation on the exterior surfaces of the protein nanocages nearby the symmetry rotation axes. As designed, the protein cages arrange in an on-axis alignment pattern.


Assuntos
Dissulfetos/química , Nanoestruturas/química , Proteínas/metabolismo , Cisteína/química , Ferritinas/genética , Ferritinas/metabolismo , Humanos , Oxirredução , Mutação Puntual , Proteínas/genética
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