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Electron. j. biotechnol ; 52: 45-51, July. 2021. ilus, tab, graf
Article in English | LILACS | ID: biblio-1283499


BACKGROUND: Acidithiobacillus ferrooxidans is a facultative anaerobe that depends on ferrous ion oxidation as well as reduced sulfur oxidation to obtain energy and is widely applied in metallurgy, environmental protection, and soil remediation. With the accumulation of experimental data, metabolic mechanisms, kinetic models, and several databases have been established. However, scattered data are not conducive to understanding A. ferrooxidans that necessitates updated information informed by systems biology. RESULTS: Here, we constructed a knowledgebase of iron metabolism of A. ferrooxidans (KIMAf) system by integrating public databases and reviewing the literature, including the database of bioleaching substrates (DBS), the database of bioleaching metallic ion-related proteins (MIRP), the A. ferrooxidans bioinformation database (Af-info), and the database for dynamics model of bioleaching (DDMB). The DBS and MIRP incorporate common bioleaching substrates and metal ion-related proteins. Af-info and DDMB integrate nucleotide, gene, protein, and kinetic model information. Statistical analysis was performed to elucidate the distribution of isolated A. ferrooxidans strains, evolutionary and metabolic advances, and the development of bioleaching models. CONCLUSIONS: This comprehensive system provides researchers with a platform of available iron metabolism-related resources of A. ferrooxidans and facilitates its application.

Acidithiobacillus/metabolism , Iron/metabolism , Kinetics , Knowledge Bases
Article in Chinese | WPRIM | ID: wpr-879516


β-thalassemia is a type of inherited hemolytic anemia caused by decreased globin production due to defect of the HBB gene. The pathogenesis of the disease is imbalance of α/β globin chains. The excess of α-globin chains will form hemichromes which can damage red blood cell membranes and lead to hemolysis, ineffective erythropoiesis, and secondary iron overload. Iron overload in turn can cause complications such as growth retardation, liver cirrhosis, cardiac insufficiency, and aggravate the disease phenotype. In recent decades, genes participating in iron metabolism have been discovered, and the mechanism of iron metabolism in the development of thalassemia has gradually been elucidated. Subsequently, by manipulating the expression of key genes in iron metabolism such as hepcidin and transferrin receptor, researchers have revealed that iron restriction can improve ineffective hematopoiesis and iron overload, which may provide a potential approach for the treatment of thalassemia. This article reviews the progress of research on iron metabolism-related genes and related pathways in β-thalassemia.

Humans , Iron/metabolism , Iron Overload/genetics , Phenotype , Research/trends , beta-Thalassemia/physiopathology
Acta Physiologica Sinica ; (6): 244-252, 2021.
Article in Chinese | WPRIM | ID: wpr-878253


The aim of this study was to investigate the effects of polarization program on the ability of macrophages to regulate iron metabolism. M1 and M2 macrophages were propagated in vitro from porcine alveolar macrophages 3D4/2 and polarized by cytokines. The 3D4/2 macrophages were treated with 20 ng/mL interferon gamma (IFN-γ) and 10 ng/mL interleukin-4 (IL-4) combined with 10 ng/mL macrophage colony-stimulating factor (M-CSF) to induce polarization to M1 and M2, respectively. After incubation for 24 h, the expression levels of inflammatory factors and iron-metabolism genes were determined using real-time qPCR, Western bot and immunofluorescence. The M1/M2 macrophages culture media supernatant was collected and used to treat porcine intestinal epithelial cells IPEC-J2. The proliferation ability of IPEC-J2 was detected using CCK-8 assay kit. Following exogenous addition of ammonium ferric citrate (FAC) to M1/M2 macrophages, the phagocytic function of macrophages was detected using fluorescein isothiocyanate-dextran (FITC-dextran) and flow cytometry. The results showed that, compared with control, M1 macrophages had higher mRNA levels of iron storage proteins (ferritin heavy and light polypeptide, i.e. FtH and FtL), hepcidin and lipocalin-2, as well as iron content. Moreover, iron enhanced the ability of M1 macrophages to phagocytize FITC-dextran. There was no significant change in these mRNA expression levels in M2 macrophages, but the mRNA expression levels of ferroportin and transferrin receptor were up-regulated. In addition, the conditioned media supernatant from M2 macrophages promoted cell proliferation of IPEC-J2. These findings indicate that M1 macrophages tend to lock iron in the cell and reduce extracellular iron content, thereby inhibiting the proliferation of extracellular bacteria. While M2 macrophages tend to excrete iron, which contributes to the proliferation of surrounding cells and thus promotes tissue repair.

Animals , Cytokines , Ferritins , Iron/metabolism , Macrophages/metabolism , Macrophages, Alveolar/metabolism , Swine
Article in Chinese | WPRIM | ID: wpr-880056


OBJECTIVE@#To detect serum hepcidin and erythroferrone levels in child-bearing women with iron deficiency anemia (IDA), and to investigate the association between them and iron status parameters.@*METHODS@#The study consisted of 65 child-bearing women (35 with iron deficiency anemia and 30 age-matched healthy women). The levels of serum iron were detected by using automated chemistry analyzer, the contents of serum ferritin were detected by electrochemiluminescence immunoassay, and the levels of serum erythroferrone and hepcidin were detected by specific enzyme-linked immunosorbent assay (ELISA) kit. The quantitative variables between two groups were compared and analyzed by SPSS22.0 software. Spearman correlation was used to detect correlation between the parameters.@*RESULTS@#The levels of Hb, serum iron, ferritin and transferrin saturation were significantly decreased in IDA patients as compared with in control group (P0.05). In IDA patients, serum hepcidin concentrations were positively correlated with hemoglobin concentration, serum iron, serum ferritin and transferrin saturation (r=0.448, r=0.496, r=0.754, r=0.491). But, serum erythroferrone concentrations showed no correlation with hemoglobin concentration, serum iron, serum ferritin, transferrin saturation and hepcidin (P>0.05).@*CONCLUSION@#Serum hepcidin levels were significantly decreased in child-bearing women with IDA, but the serum erythroferrone levels were not obviously different between two groups, suggesting that serum erythroferrone may be not involved in the regulation of iron metabolism in child-bearing women with mild and moderate IDA.

Anemia, Iron-Deficiency , Child , Enzyme-Linked Immunosorbent Assay , Female , Ferritins , Hepcidins , Humans , Iron/metabolism
Braz. j. microbiol ; 49(supl.1): 40-46, 2018. tab
Article in English | LILACS | ID: biblio-974339


Abstract Bacterial endophytes are considered to have a beneficial effect on host plants, improving their growth by different mechanisms. The objective of this study was to investigate the capacity of four endophytic Bacillus strains to solubilize iron phosphate (Fe-P), produce siderophores and indole-acetic acid (IAA) in vitro, and to evaluate their plant growth promotion ability in greenhouse conditions by inoculation into pearl millet cultivated in a P-deficient soils without P fertilization, with Araxá rock phosphate or soluble triple superphosphate. All strains solubilized Fe-P and three of them produced carboxylate-type siderophores and high levels of IAA in the presence of tryptophan. Positive effect of inoculation of some of these strains on shoot and root dry weight and the N P K content of plants cultivated in soil with no P fertilization might result from the synergistic combination of multiple plant growth promoting (PGP) traits. Specifically, while B1923 enhanced shoot and root dry weight and root N P content of plants cultivated with no P added, B2084 and B2088 strains showed positive performance on biomass production and accumulation of N P K in the shoot, indicating that they have higher potential to be microbial biofertilizer candidates for commercial applications in the absence of fertilization.

Bacillus/metabolism , Food/metabolism , Pennisetum/growth & development , Pennisetum/microbiology , Endophytes/metabolism , Indoleacetic Acids/metabolism , Phosphates/analysis , Phosphates/metabolism , Bacillus/genetics , Siderophores/metabolism , Plant Roots/growth & development , Plant Roots/metabolism , Plant Roots/microbiology , Pennisetum/metabolism , Endophytes/genetics , Iron/metabolism
Braz. j. microbiol ; 49(supl.1): 269-275, 2018. tab, graf
Article in English | LILACS | ID: biblio-974344


ABSTRACT Fusarium oxysporum f. sp. lycopersici is a phytopathogenic fungus that causes vascular wilt in tomato plants. In this work we analyze the influence of metal salts such as iron and copper sulphate, as well as that of bathophenanthrolinedisulfonic acid (iron chelator) and bathocuproinedisulfonic acid (copper chelator) on the activity of laccases in the intra (IF) and extracellular fractions (EF) of the wild-type and the non-pathogenic mutant strain (rho1::hyg) of F. oxysporum. The results show that laccase activity in the IF fraction of the wild and mutant strain increased with the addition of iron chelator (53.4 and 114.32%; respectively). With copper, it is observed that there is an inhibition of the activity with the addition of CuSO4 for the EF of the wild and mutant strain (reduction of 82 and 62.6%; respectively) and for the IF of the mutant strain (54.8%). With the copper chelator a less laccase activity in the IF of the mutant strain was observed (reduction of 53.9%). The results obtained suggest a different regulation of intracellular laccases in the mutant strain compared with the wild type in presence of CuSO4 and copper chelator which may be due to the mutation in the rho gene.

Fungal Proteins/metabolism , Copper/metabolism , Laccase/metabolism , Fusarium/enzymology , Iron/metabolism , Plant Diseases/microbiology , Fungal Proteins/genetics , Fungal Proteins/chemistry , Lycopersicon esculentum/microbiology , Laccase/genetics , Laccase/chemistry , Fusarium/genetics , Fusarium/chemistry
Braz. j. microbiol ; 48(4): 656-670, Oct.-Dec. 2017. tab, graf
Article in English | LILACS | ID: biblio-889178


ABSTRACT This study aimed to explore the effects of two siderophore-producing bacterial strains on iron absorption and plant growth of peanut in calcareous soil. Two siderophore-producing bacterial strains, namely, YZ29 and DZ13, isolated from the rhizosphere soil of peanut, were identified as Paenibacillus illinoisensis and Bacillus sp., respectively. In potted experiments, YZ29 and DZ13 enhanced root activity, chlorophyll and active iron content in leaves, total nitrogen, phosphorus and potassium accumulation of plants and increased the quality of peanut kernels and plant biomass over control. In the field trial, the inoculated treatments performed better than the controls, and the pod yields of the three treatments inoculated with YZ29, DZ13, and YZ29 + DZ13 (1:1) increased by 37.05%, 13.80% and 13.57%, respectively, compared with the control. Based on terminal restriction fragment length polymorphism analysis, YZ29 and DZ13 improved the bacterial community richness and species diversity of soil surrounding the peanut roots. Therefore, YZ29 and DZ13 can be used as candidate bacterial strains to relieve chlorosis of peanut and promote peanut growth. The present study is the first to explore the effect of siderophores produced by P. illinoisensis on iron absorption.

Arachis/growth & development , Arachis/microbiology , Bacillus/metabolism , Paenibacillus/metabolism , Iron/metabolism , Arachis/metabolism , Arachis/chemistry , Seeds/growth & development , Seeds/metabolism , Seeds/microbiology , Seeds/chemistry , Soil/chemistry , Soil Microbiology , Bacillus/isolation & purification , Bacillus/classification , Bacillus/genetics , Biological Transport , Siderophores/metabolism , Plant Roots/microbiology , Paenibacillus/isolation & purification , Paenibacillus/classification , Paenibacillus/genetics , Rhizosphere , Agricultural Inoculants/metabolism
Acta bioquím. clín. latinoam ; 51(3): 375-378, set. 2017.
Article in Spanish | LILACS | ID: biblio-886132


En las últimas décadas se ha avanzado en el conocimiento de la regulación del metabolismo del Hierro (Fe). La Hepcidina (Hp), producida por los hepatocitos, regula la absorción de hierro desde el tubo digestivo y la liberación desde los depósitos del sistema macrofágico y del hígado. En caso de deficiencia de Fe, la Hp está disminuida entregando Fe a la transferrina (Tf). El aumento de Fe y de las citoquinas de la inflamación estimulan la producción de Hp. El ejecutor de la Hp es la Ferroportina (FP), único exportador de Fe. Hay reguladores naturales de la Hp, como la Matriptasa 2. Las mutaciones que limitan su expresión inducen dificultades en la disponibilidad de Fe (IRIDA, sobrecarga de Fe). En los últimos años se ha identificado la Eritroferrona, producida por los eritroblastos activos en la eritropoyesis. Inhibe la síntesis de Hp, permitiendo la liberación del hierro de los depósitos y su absorción por el tubo digestivo, para facilitar la disponibilidad de Fe para la eritropoyesis. Aún no está definido cómo se podrán utilizar estos elementos en el campo diagnóstico, su estandarización y su aplicación terapéutica, pero es probable que resulten de gran utilidad.

In the last decades, a lot of progress has been made on the knowledge of iron (Fe) metabolism regulation. Hepcidin (Hp) is produced by hepatocytes and it regulates the iron absorption from the duodenum and the liberation from macrophages and from the liver. When there is iron deficiency, Hp, which delivers iron to transferrin (Tf), is low. Iron overload and inflammation cytokines stimulate Hp production. The Hp natural executor is Ferroportin (FP), which is the only iron exporter from the cells. One of the natural regulators of Hp is Matriptasa 2, which down regulates Hp. Mutations that limit their expression induce iron overload and anemia (IRIDA). In the last few years, Erythroferrone (ERFE) was discovered. ERFE is produced by active erythroblasts: it inhibits Hp synthesis, allowing the iron liberation from deposits and its duodenal absorption, and also the iron release from macrophages facilitating the erythroid production. The erythroblastic activity, even ineffective, acts as a stimulus of ERFE synthesis. Until now, it has not been defined yethow these different variables could be used for diagnosis, its standardization, or for therapeutic applications, but it is highly probable that they will improve our knowledge and managements kills in this field.

Nas últimas décadas háavanços no conhecimento da regulação do metabolismo do Ferro (Fe). A Hepcidina (Hp), produzida pelos hepatócitos, regula a absorção do ferro desde o tubo digestivo e a liberação desde os depósitos do sistema macrofágico e do fígado. Em caso de deficiência de Fe, a Hp está diminuída entregando Fe à transferrina (Tf). O aumento de Fe e as citoquinas da inflamação estimulam a produção de Hp. O executor da Hp é a Ferroportina (Fp), único exportador de Fe. Há reguladores naturais da Hp, como a Matriptase 2. As mutações que limitam sua expressão induzem dificultades na disponibilidade de Fe (IRIDA, sobrecarga de Fe). Nos últimos anos se identificou que a Eritroferrona, produzida pelos eritroblastosativos na eritropoiese inibe a síntese de Hp, permitindo a liberação de ferro dos depósitos e a absorção pelo tubo digestivo, para facilitar a disponibilidade de Fe para a eritropoiese. Ain da não sedefiniu como poderãoser utilizadosestes elementos no campo diagnóstico, sua padronização e sua aplicação terapêutica, mas é provável que sejam de grande utilidade.

Humans , Iron Metabolism Disorders/diagnosis , Hepcidins , Iron/metabolism , Anemia , Iron
Pesqui. vet. bras ; 37(6): 598-602, jun. 2017. tab, ilus
Article in English | LILACS, VETINDEX | ID: biblio-895458


Chronic anaemia is one of the most severe complications of chronic kidney disease, contributing to morbidity and mortality caused by the disease; therefore, bone marrow cytological evaluation is needed to monitor the progression of anaemia. This study aimed to correlate the anaemia in dogs at different stages of chronic kidney disease with their serum biochemistry, myelogram results and serum erythropoietin findings. Sixty-three dogs were grouped according to International Renal Interest Society (IRIS) classification in stages 1, 2, 3 and 4. Haematologic, serum and urinary biochemistry and serum erythropoietin were performed for comparison with the findings of bone marrow cytology obtained by aspiration of the manubrium. Cytological findings for erythroid hypoplasia were described in 93.65% of dogs, and the anaemia was observed in 84.1% of them. The haematological findings were correlated with azotaemia (p<0.05). It was concluded that the erythroid hypoplasia has correlation with persistent anaemia in dogs at all stages of chronic kidney disease, with iron deficiency in dogs in the early stages and with peripheral destruction of erythrocytes caused by azotaemia.(AU)

A anemia crônica é umas das complicações mais graves da doença renal crônica, contribuindo para a morbidade e mortalidade causada pela doença; Portanto, a avaliação citológica da medula óssea é necessária para monitorar a progressão da anemia. Assim, esse estudo objetivou correlacionar a anemia em cães em diferentes estágios da doença renal crônica aos achados de bioquímica sérica, mielograma e concentração sérica de eritropoietina. Sessenta e três cães foram agrupados de acordo com a classificação da International Renal Interest Society (IRIS) em estágios 1, 2, 3 e 4. Foram realizadas análises hematológicas, bioquímicas séricas e urinárias, e dosagem sérica de eritropoetina para comparação com os achados medulares obtidos por citologia aspirativa do manúbrio. Os achados citológicos de hipoplasia eritróide foram descritos em 93,65% dos cães, e a anemia foi observada em 84,1% dos cães. Os resultados hematológicos foram correlacionados com azotemia (p<0,05). Concluiu-se que a hipoplasia eritróide teve associação com a anemia persistente em cães em todas as fases de doença renal crônica, com deficiência de ferro em cães em fases iniciais e com a destruição periférica dos eritrócitos causada pela azotemia.(AU)

Animals , Dogs , Bone Marrow , Erythropoietin/blood , Renal Insufficiency, Chronic/veterinary , Anemia/complications , Myeloid Cells , Erythrocytes , Iron/metabolism
Electron. j. biotechnol ; 25: 50-57, ene. 2017. tab, ilus, graf
Article in English | LILACS | ID: biblio-1008584


Background: Traditional methods of obtaining arsenic have disadvantages such as high cost and high energy consumption. Realgar is one of the most abundant arsenic sulphide minerals and usually treated as waste in industry. The aim of the present study was to screen an arsenic tolerant bacterium used for bioleaching arsenic from realgar. Results: An acidophilic iron-oxidizing bacterium BYQ-12 was isolated from Wudalianchi volcanic lake in northeast China. BYQ-12 was a motile, rod-shaped gram-negative bacterium with an optimum growth at 30°C and pH 2.5. 16S rDNA phylogeny showed that BYQ-12 was a new strain of Acidithiobacillus ferrooxidans. The inhibitory concentrations (ICs) of arsenite and arsenate were 32 and 64 mM, respectively. A significant second-order model was established using a Box­Behnken design of response surface methodology (BBD-RSM) and it estimated that a maximum arsenic bioleaching rate (73.97%) could be obtained when the pulp concentration, pH and initial ferrous ion concentration were set at optimized values of 0.95% w/v, 1.74 and 3.68 g/L, respectively. SEM, EDS and XRD analyses also revealed that there was direct bioleaching besides indirect electrochemical leaching in the arsenic bioleaching system. Conclusion: From this work we were successful in isolating an acidophilic, arsenic tolerant ferrous iron-oxidizing bacterium. The BBD-RSM analysis showed that maximum arsenic bioleaching rate obtained under optimum conditions, and the most effective factor for arsenic leaching was initial ferrous ion concentration. These revealed that BYQ-12 could be used for bioleaching of arsenic from arsenical minerals.

Arsenic/metabolism , Arsenic/chemistry , Acidithiobacillus/isolation & purification , Oxidation-Reduction , Hydrogen-Ion Concentration , Iron/metabolism
Rev. argent. microbiol ; 48(4): 342-346, dic. 2016. ilus, tab
Article in Spanish | LILACS | ID: biblio-1041771


Arthrobacter agilis UMCV2 es una bacteria rizosférica que promueve el crecimiento vegetal de plantas leguminosas proveyéndoles hierro soluble. Un segundo mecanismo de promoción se da a través de la producción de compuestos volátiles que estimulan los mecanismos de absorción de hierro. Adicionalmente, A. agilis UMCV2 tiene la capacidad de inhibir el crecimiento de organismos fitopatógenos. En el presente trabajo se emplea una combinación de las técnicas de reacción en cadena de la polimerasa cuantitativa e hibridación in situ con fluorescencia para detectar y cuantificar la presencia de la bacteria en los tejidos internos de la planta leguminosa Medicago truncatula. Nuestros resultados demuestran que A. agilis UMCV2 se comporta como una bacteria endófita de M. truncatula especialmente en medios donde el hierro está disponible.

Arthrobacter agilis UMCV2 is a rhizosphere bacterium that promotes legume growth by solubilization of iron, which is supplied to the plant. A second growth promotion mechanism produces volatile compounds that stimulate iron uptake activities. Additionally, A. agilis UMCV2 is capable of inhibiting the growth of phytopathogens. A combination of quantitative polymerase chain reaction and fluorescence in situ hybridization techniques were used here to detect and quantify the presence of the bacterium in the internal tissues of the legume Medicago truncatula. Our results demonstrate that A. agilis UMCV2 behaves as an endophytic bacterium of M. truncatula, particularly in environments where iron is available.

Arthrobacter/growth & development , Medicago truncatula/growth & development , Medicago truncatula/microbiology , Iron/metabolism , Polymerase Chain Reaction/methods , In Situ Hybridization/methods , Rhizosphere , Endophytes/growth & development
J. bras. nefrol ; 38(3): 351-355, July-Sept. 2016.
Article in English | LILACS | ID: lil-796207


Abstract Anemia is a common complication and its impact on morbimortality in patients with chronic kidney disease (CKD) is well known. The discovery of hepcidin and its functions has contributed to a better understanding of iron metabolism disorders in CKD anemia. Hepcidin is a peptide mainly produced by hepatocytes and, through a connection with ferroportin, it regulates iron absorption in the duodenum and its release of stock cells. High hepcidin concentrations described in patients with CKD, especially in more advanced stages are attributed to decreased renal excretion and increased production. The elevation of hepcidin has been associated with infection, inflammation, atherosclerosis, insulin resistance and oxidative stress. Some strategies were tested to reduce the effects of hepcidin in patients with CKD, however more studies are necessary to assess the impact of its modulation in the management of anemia in this population.

Resumo Anemia é uma complicação frequente e seu impacto na morbimortalidade é bem conhecido em pacientes com doença renal crônica (DRC). A descoberta da hepcidina e de suas funções contribuíram para melhor compreensão dos distúrbios do metabolismo de ferro na anemia da DRC. Hepcidina é um peptídeo produzido principalmente pelos hepatócitos, e através de sua ligação com a ferroportina, regula a absorção de ferro no duodeno e sua liberação das células de estoque. Altas concentrações de hepcidina descritas em pacientes com DRC, principalmente em estádios mais avançados, são atribuídas à diminuição da excreção renal e ao aumento de sua produção. Elevação de hepcidina tem sido associada à ocorrência de infecção, inflamação, aterosclerose, resistência à insulina e estresse oxidativo. Algumas estratégias foram testadas para diminuir os efeitos da hepcidina em pacientes com DRC, entretanto, serão necessários mais estudos para avaliar o impacto de sua modulação no manejo da anemia nessa população.

Humans , Renal Insufficiency, Chronic/metabolism , Hepcidins/physiology , Iron/metabolism
Rev. cuba. hematol. inmunol. hemoter ; 32(1): 4-14, ene.-mar. 2016. ilus
Article in Spanish | LILACS | ID: lil-794142


La existencia humana está indisolublemente unida al hierro, que es parte de una amplia variedad de enzimas claves como catalasas, aconitasas, ribonucleótido reductasa, peroxidasas y citocromos, que explotan la flexibilidad de su química redox para ejecutar un elevado número de reacciones esenciales para la vida. El cuerpo humano ha evolucionado para conservar el hierro en diferentes formas, incluido su reciclaje después de la ruptura de los eritrocitos y la retención en ausencia de un mecanismo de excreción. El metabolismo del hierro está balanceado por dos sistemas regulatorios: uno sistémico basado en la hormona hepcidina y la proteína exportadora ferroportina, y el otro que controla el metabolismo celular través de las proteínas reguladoras de hierro (IRP) que se unen a los elementos de respuesta al hierro (IRE) de los ARNm regulados. Estos sistemas funcionan de modo coordinado lo que evita, tanto la deficiencia como el exceso del mineral(AU)

Human existence is indissolubly linked to iron, which is part of a wide variety of key enzymes such as catalase, aconitases, ribonucleotide reductase, peroxidases and cytochromes, exploiting the flexibility of its redox chemistry to run a large number of reactions essential for life. Human body has evolved to keep iron in different forms, including recycling after rupture of erythrocytes and the retention without excretion mechanism. Iron metabolism is balanced by two regulatory systems: one based on systemic hormone hepcidin protein export and ferroportin, and the other, which controls cell metabolism through the iron regulatory protein (IRP) binding to the mRNAs regulated iron regulatory elements (IRE). These systems work in a coordinated manner avoiding both deficiency and excess(AU)

Humans , Male , Female , Iron/metabolism , Heme , Hepcidins/metabolism
Belo Horizonte; s.n; 2016. 60 p.
Thesis in Portuguese | ColecionaSUS, LILACS, ColecionaSUS | ID: biblio-942654


A malária é uma doença parasitária prevalente principalmente em regiões tropicais e subtropicais do mundo. Indivíduos infectados com Plasmodium vivax, mais prevalente espécie do parasito no Brasil, apresentam dentre outras características, a anemia como uma das principais complicações. Além disso, essa espécie é capaz de desenvolver hipnozoítos que podem levar ao reaparecimento dos sintomas em episódios denominados recaídas. No entanto, os mecanismos responsáveis pela ativação desses hipnozoítos ainda são desconhecidos. O metabolismo do ferro tem sido associado com o desenvolvimento de diversos organismos, inclusive Plasmodium, além de estar envolvido em distúrbios hematológicos, como a anemia. Assim, a hipótese investigada neste trabalho é que as moléculas envolvidas na homeostase do ferro podem ser utilizadas como biomarcadores de recaída e/ou de anemia através da análise dos polimorfismos C282Y e H63D no gene da hemocromatose (HFE) e C326Y/S no gene da ferroportina (FPN).

Os indivíduos analisados foram divididos segundo os dois grandes temas desse estudo: (1)indivíduos que tiveram uma ou múltiplas recaídas por P. vivax e (2) indivíduos anêmicos e não anêmicos infectados por P. vivax. A frequência do polimorfismo H63D identificada no grupo de múltiplas recaídas foi de 17%, enquanto que no grupo de uma recaída foi de apenas 2%. Não foi observada diferença significativa entre indivíduos anêmicos e não anêmicos para os polimorfismos HFE H63D e C282Y. Tanto no grupo de anemia quanto no grupo de recaída não foram encontrados os polimorfismos C326Y e C326S no gene da ferroportina. Os resultados obtidos nesse estudo evidenciam que o polimorfismo HFE H63D pode estar relacionado ao acúmulo de ferro nos indivíduos com múltiplas recaídas, sugerindo que esse polimorfismo pode ser considerado um biomarcador de múltiplas recaídas. Além disso, esses resultados abrem a perspectiva de realização de novos estudos que contribuam para a elucidação dos mecanismos que desencadeiam as múltiplas recaídas. Esses resultados podem inclusive contribuir para novas estratégias nos programas de eliminação da malária, como projetos de monitoramento de indivíduos que possuam predisposição ao acúmulo de ferro, e também resistência ao tratamento, principalmente nas áreas endêmicas.

Male , Female , Humans , Anemia/complications , Hemochromatosis/genetics , Iron/metabolism , Malaria, Vivax/genetics , Plasmodium vivax/pathogenicity , Recurrence
Electron. j. biotechnol ; 18(5): 333-337, Sept. 2015. ilus, graf, tab
Article in English | LILACS | ID: lil-764017


Background Ethylene is capable of promoting seed germination in some plant species. Mobilization of metals such as Fe, Cu, Mn, and Zn in mature seeds takes place when seeds are germinating. However, whether ethylene is involved in the regulation of soybean seed germination and metal element mobilization during early seed germination stage remains unknown. In the present study, seeds were treated with ethylene synthesis inhibitor aminoethoxyvinylglycine (AVG) and ethylene precursor 1-aminocyclopropane-1-carboxylic acid (ACC), and double distilled H2O (ddH(2)0) treatment was used as control. Ethylene emission, ACC synthase (ACS) expression, ACS enzyme activity and Ca, Zn, Mn, Cu and Fe content in hypocotyls were qualified to analyze the relationship between ethylene and mobilization of these elements. Results The results showed that ACS expression, ACS enzyme activity and ethylene emission peaked at 1 and 7 d after sowing. AVG inhibited ethylene production, promoted the hypocotyls length, ACS expression and its activity, concentrations of total and HCl-extractable Zn, and HCl-extractable Fe in hypocotyls, while ACC caused opposite effects. AVG and ACC treatment had no significantly effects on total and HCl-extractable Ca, Cu and HCl-extractable Mn. Total Mn concentration was promoted by AVG at 1, 3, and 5 d significantly, while ACC treatment tended to have no significantly effects on Mn concentration. Conclusion These findings suggested that ethylene is at least partly involved in the regulation of soybean seed germination. Remobilization of Zn and Fe may be negatively regulated by ethylene.

Seeds , Soybeans , Germination , Ethylenes , Lyases/metabolism , Metals/metabolism , Zinc/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Iron/metabolism
Braz. j. microbiol ; 46(1): 195-200, 05/2015. tab, graf
Article in English | LILACS | ID: lil-748254


Pleurotus ostreatus is able to bioaccumulate several metals in its cell structures; however, there are no reports on its capacity to bioaccumulate iron. The objective of this study was to evaluate cultivation variables to increase iron bioaccumulation in P. ostreatus mycelium. A full factorial design and a central composite design were utilized to evaluate the effect of the following variables: nitrogen and carbon sources, pH and iron concentration in the solid culture medium to produce iron bioaccumulated in mycelial biomass. The maximum production of P. ostreatus mycelial biomass was obtained with yeast extract at 2.96 g of nitrogen L−1 and glucose at 28.45 g L−1. The most important variable to bioaccumulation was the iron concentration in the cultivation medium. Iron concentration at 175 mg L−1 or higher in the culture medium strongly inhibits the mycelial growth. The highest iron concentration in the mycelium was 3500 mg kg−1 produced with iron addition of 300 mg L−1. The highest iron bioaccumulation in the mycelium was obtained in culture medium with 150 mg L−1 of iron. Iron bioaccumulation in P. ostreatus mycelium is a potential alternative to produce non-animal food sources of iron.

Iron/metabolism , Mycelium/metabolism , Pleurotus/metabolism , Biomass , Carbon/metabolism , Culture Media/chemistry , Hydrogen-Ion Concentration , Mycelium/growth & development , Nitrogen/metabolism , Pleurotus/growth & development
Article in English | WPRIM | ID: wpr-19167


Cryptosporidium andersoni ATP-binding cassette (CaABC) is an important membrane protein involved in substrate transport across the membrane. In this research, the nucleotide binding domain (NBD) of CaABC gene was amplified by PCR, and the eukaryotic expression vector of pEGFP-C1-CaNBD was reconstructed. Then, the recombinant plasmid of pEGFP-C1-CaNBD was transformed into the mouse intestinal epithelial cells (IECs) to study the iron transportation function of CaABC. The results indicated that NBD region of CaABC gene can significantly elevate the transport efficiency of Ca2+, Mg2+, K+, and HCO3 - in IECs (P<0.05). The significance of this study is to find the ATPase inhibitors for NBD region of CaABC gene and to inhibit ATP binding and nutrient transport of CaABC transporter. Thus, C. andersoni will be killed by inhibition of nutrient uptake. This will open up a new way for treatment of cryptosporidiosis.

ATP-Binding Cassette Transporters/chemistry , Adenosine Triphosphate/metabolism , Amino Acid Sequence , Animals , Calcium/metabolism , Cloning, Molecular , Cryptosporidiosis/parasitology , Cryptosporidium/chemistry , Humans , Iron/metabolism , Mice , Molecular Sequence Data , Protein Structure, Tertiary , Protozoan Proteins/chemistry , Sequence Alignment
Biol. Res ; 48: 1-8, 2015. graf
Article in English | LILACS | ID: biblio-950787


BACKGROUND: Hepcidin, encoding by HAMP gene, is the pivotal regulator of iron metabolism, controlling the systemic absorption and transportation of irons from intracellular stores. Abnormal levels of HAMP expression alter plasma iron parameters and lead to iron metabolism disorders. Therefore,itis animportant goal to understand the mechanisms controlling HAMP gene expression. RESULTS: Overexpression of Sox2 decrease basal expression of HAMP or induced by IL-6 or BMP-2, whereas, knockdown of Sox2 can increase HAMP expression, furthermore, two potential Sox2-binding sites were identified within the human HAMP promoter. Indeed, luciferase experiments demonstrated that deletion of any Sox2-binding site impaired the negative regulation of Sox2 on HAMP promoter transcriptional activity in basal conditions. ChIP experiments showed that Sox2 could directly bind to these sites. Finally, we verified the role of Sox2 to negatively regulate HAMP expression in human primary hepatocytes. CONCLUSION: We found that Sox2 as a novel factor to bind with HAMP promoter to negatively regulate HAMP expression, which may be further implicated as a therapeutic option for the amelioration of HAMP-overexpression-related diseases, including iron deficiency anemia.

Humans , Gene Expression Regulation, Neoplastic/genetics , Hepatocytes/metabolism , SOXB1 Transcription Factors/genetics , Hepcidins/genetics , Plasmids/genetics , Binding Sites , Interleukin-6/metabolism , Promoter Regions, Genetic/genetics , Bone Morphogenetic Protein 2/metabolism , SOXB1 Transcription Factors/metabolism , Gene Knockdown Techniques , Hep G2 Cells , Hepcidins/metabolism , Genetic Vectors , Anemia/genetics , Anemia/metabolism , Iron/metabolism , Luciferases
Article in English | IMSEAR | ID: sea-157687


A substantial body of epidemiological and experimental data suggests the significance of serum iron as an important cardiovascular risk factor. There are many conflicting reports on the hypothesis that body iron stores are associated with risk of coronary heart disease. The likely mechanism by which iron may play a pathogenic role in cardiovascular disease has been postulated. The recent discovery of the HFE C282Y mutation commonly seen in hereditary hemochromatosis and its reported association with increased risk of coronary heart disease has increased the need to evaluate its role in the development of cardiovascular disease. Overall, understanding the role of iron in relation to cardiovascular health may be an important tool to help stratify risk for cardiovascular disease.

Cardiovascular Diseases/epidemiology , Cardiovascular Diseases/genetics , Ferritins/blood , Ferritins/metabolism , Hemochromatosis/genetics , Histocompatibility Antigens Class I/genetics , Humans , Iron/blood , Iron/metabolism , Membrane Proteins/analogs & derivatives , Membrane Proteins/genetics , Mutation , Risk