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1.
Ann Hematol ; 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38763941

RESUMO

REHem-AR was created in 2013. The progressive implementation of neonatal screening for haemoglobinopathies in Spanish autonomous communities where the registry had not been implemented, as well as the addition of new centres during this period, has considerably increased the sample of patients covered. In this study, we update our previous publication in this area, after a follow-up of more than 5 years. An observational, descriptive, multicentre and ambispective study of adult and paediatric patients with haemoglobinopathies and rare anaemias registered in REHem was performed. The data are from a cross-sectional analysis performed on 1 June, 2023. The study population comprised 1,756 patients, of whom 1,317 had SCD, 214 had thalassaemia and 224 were diagnosed with another condition. Slightly more than one third of SCD patients (37%) were diagnosed based on neonatal bloodspot screening, and the mean age at diagnosis was 2.5 years; 71% of thalassaemia patients were diagnosed based on the presence of anaemia. Vaso-occlusive crisis and acute chest syndrome continue to be the most frequent complications in SCD. HSCT was performed in 83 patients with SCD and in 50 patients with thalassaemia. Since the previous publication, REHem-AR has grown in size by more than 500 cases. SCD and TM are less frequent in Spain than in other European countries, although the data show that rare anaemias are frequent within rare diseases. REHem-AR constitutes an important structure for following the natural history of rare anaemias and enables us to calculate investment needs for current and future treatments.

2.
Biochem J ; 476(1): 85-99, 2019 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-30523059

RESUMO

Macrophage classical M1 activation via TLR4 triggers a variety of responses to achieve the elimination of foreign pathogens. During this process, there is also an increase in lipid droplets which contain large quantities of triacylglycerol (TAG) and phospholipid (PL). The functional consequences of this increment in lipid mass are poorly understood. Here, we studied the contribution of glycerolipid synthesis to lipid accumulation, focusing specifically on the first and rate-limiting enzyme of the pathway: glycerol-3-phosphate acyltransferase (GPAT). Using bone marrow-derived macrophages (BMDMs) treated with Kdo2-lipid A, we showed that glycerolipid synthesis is induced during macrophage activation. GPAT4 protein level and GPAT3/GPAT4 enzymatic activity increase during this process, and these two isoforms were required for the accumulation of cell TAG and PL. The phagocytic capacity of Gpat3-/- and Gpat4-/- BMDM was impaired. Additionally, inhibiting fatty acid ß-oxidation reduced phagocytosis only partially, suggesting that lipid accumulation is not necessary for the energy requirements for phagocytosis. Finally, Gpat4-/- BMDM expressed and released more pro-inflammatory cytokines and chemokines after macrophage activation, suggesting a role for GPAT4 in suppressing inflammatory responses. Together, these results provide evidence that glycerolipid synthesis directed by GPAT4 is important for the attenuation of the inflammatory response in activated macrophages.


Assuntos
1-Acilglicerol-3-Fosfato O-Aciltransferase/metabolismo , Glicerol-3-Fosfato O-Aciltransferase/metabolismo , Lipogênese , Macrófagos/enzimologia , Fosfolipídeos/biossíntese , Triglicerídeos/biossíntese , 1-Acilglicerol-3-Fosfato O-Aciltransferase/genética , Animais , Glicerol-3-Fosfato O-Aciltransferase/genética , Inflamação/enzimologia , Inflamação/genética , Inflamação/patologia , Ativação de Macrófagos/genética , Macrófagos/patologia , Camundongos , Camundongos Knockout , Fosfolipídeos/genética , Triglicerídeos/genética
4.
Small ; 14(15): e1703963, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29479814

RESUMO

Although cubic rock salt-CoO has been extensively studied, the magnetic properties of the main nanoscale CoO polymorphs (hexagonal wurtzite and cubic zinc blende structures) are rather poorly understood. Here, a detailed magnetic and neutron diffraction study on zinc blende and wurtzite CoO nanoparticles is presented. The zinc blende-CoO phase is antiferromagnetic with a 3rd type structure in a face-centered cubic lattice and a Néel temperature of TN (zinc-blende) ≈225 K. Wurtzite-CoO also presents an antiferromagnetic order, TN (wurtzite) ≈109 K, although much more complex, with a 2nd type order along the c-axis but an incommensurate order along the y-axis. Importantly, the overall magnetic properties are overwhelmed by the uncompensated spins, which confer the system a ferromagnetic-like behavior even at room temperature.

5.
Small ; 14(21): e1704396, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29667302

RESUMO

Voltage-driven manipulation of magnetism in electrodeposited 200 nm thick nanoporous single-phase solid solution Cu20 Ni80 (at%) alloy films (with sub 10 nm pore size) is accomplished by controlled reduction-oxidation (i.e., redox) processes in a protic solvent, namely 1 m NaOH aqueous solution. Owing to the selectivity of the electrochemical processes, the oxidation of the CuNi film mainly occurs on the Cu counterpart of the solid solution, resulting in a Ni-enriched alloy. As a consequence, the magnetic moment at saturation significantly increases (up to 33% enhancement with respect to the as-prepared sample), while only slight changes in coercivity are observed. Conversely, the reduction process brings Cu back to its metallic state and, remarkably, it becomes alloyed to Ni again. The reported phenomenon is fully reversible, thus allowing for the precise adjustment of the magnetic properties of this system through the sign and amplitude of the applied voltage.

6.
Biochem J ; 474(18): 3093-3107, 2017 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-28729426

RESUMO

Glycerol-3-phosphate acyltransferases (GPATs) catalyze the first and rate-limiting step in the de novo glycerolipid synthesis. The GPAT2 isoform differs from the other isoforms because its expression is restricted to male germ cells and cancer cells. It has been recently reported that GPAT2 expression in mouse testis fluctuates during sexual maturation and that it is regulated by epigenetic mechanisms in combination with vitamin A derivatives. Despite progress made in this field, information about GPAT2 role in the developing male germ cells remains unclear. The aim of the present study was to confirm the hypothesis that GPAT2 is required for the normal physiology of testes and male germ cell maturation. The gene was silenced in vivo by inoculating lentiviral particles carrying the sequence of a short-hairpin RNA targeting Gpat2 mRNA into mouse testis. Histological and gene expression analysis showed impaired spermatogenesis and arrest at the pachytene stage. Defects in reproductive fitness were also observed, and the analysis of apoptosis-related gene expression demonstrated the activation of apoptosis in Gpat2-silenced germ cells. These findings indicate that GPAT2 protein is necessary for the normal development of male gonocytes, and that its absence triggers apoptotic mechanisms, thereby decreasing the number of dividing germ cells.


Assuntos
Glicerol-3-Fosfato O-Aciltransferase/metabolismo , Túbulos Seminíferos/metabolismo , Espermatogênese , Espermatozoides/enzimologia , Animais , Apoptose , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Glicerol-3-Fosfato O-Aciltransferase/antagonistas & inibidores , Glicerol-3-Fosfato O-Aciltransferase/genética , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Células HEK293 , Humanos , Masculino , Camundongos Endogâmicos BALB C , Microscopia de Fluorescência , Estágio Paquíteno , Interferência de RNA , RNA Mensageiro/metabolismo , RNA Interferente Pequeno , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Túbulos Seminíferos/citologia , Túbulos Seminíferos/crescimento & desenvolvimento , Espermatozoides/citologia , Espermatozoides/metabolismo
7.
Artigo em Inglês | MEDLINE | ID: mdl-27377347

RESUMO

Our understanding of the synthesis and remodeling of mitochondrial phospholipids remains incomplete. Two isoforms of glycerol-3-phosphate acyltransferase (GPAT1 and 2) and two isoforms of acylglycerol-3-phosphate acyltransferase (AGPAT4 and 5) are located on the outer mitochondrial membrane, suggesting that both lysophosphatidic acid and phosphatidic acid are synthesized in situ for de novo glycerolipid biosynthesis. However, it is believed that the phosphatidic acid substrate for cardiolipin and phosphatidylethanolamine biosynthesis is produced at the endoplasmic reticulum whereas the phosphatidic acid synthesized in the mitochondria must be transferred to the endoplasmic reticulum before it undergoes additional steps to form the mature phospholipids that are trafficked back to the mitochondria. It is unclear whether mitochondrial phospholipids are remodeled by mitochondrial acyltransferases or whether lysophospholipids must return to the endoplasmic reticulum or to the mitochondrial associated membrane for reesterification. In this review we will focus on the few glycerolipid acyltransferases that are known to be mitochondrial. This article is part of a Special Issue entitled: Lipids of Mitochondria edited by Guenther Daum.


Assuntos
Aciltransferases/metabolismo , Glicerofosfolipídeos/metabolismo , Mitocôndrias/metabolismo , Animais , Retículo Endoplasmático/metabolismo , Glicerol-3-Fosfato O-Aciltransferase , Humanos , Metabolismo dos Lipídeos/fisiologia , Transporte Proteico/fisiologia
8.
Biochem J ; 471(2): 211-20, 2015 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-26268560

RESUMO

Spermatogenesis is a highly regulated process that involves both mitotic and meiotic divisions, as well as cellular differentiation to yield mature spermatozoa from undifferentiated germinal stem cells. Although Gpat2 was originally annotated as encoding a glycerol-3-phosphate acyltransferase by sequence homology to Gpat1, GPAT2 is highly expressed in testis but not in lipogenic tissues and is not up-regulated during adipocyte differentiation. New data show that GPAT2 is required for the synthesis of piRNAs (piwi-interacting RNAs), a group of small RNAs that protect the germ cell genome from retrotransposable elements. In order to understand the relationship between GPAT2 and its role in the testis, we focused on Gpat2 expression during the first wave of mouse spermatogenesis. Gpat2 expression was analysed by qPCR (quantitative real-time PCR), in situ hybridization, immunohistochemistry and Western blotting. Gpat2 mRNA content and protein expression were maximal at 15 dpp (days post-partum) and were restricted to pachytene spermatocytes. To achieve this transient expression, both epigenetic mechanisms and trans-acting factors are involved. In vitro assays showed that Gpat2 expression correlates with DNA demethylation and histone acetylation and that it is up-regulated by retinoic acid. Epigenetic regulation by DNA methylation was confirmed in vivo in germ cells by bisulfite sequencing of the Gpat2 promoter. Consistent with the initiation of meiosis at 11 dpp, methylation decreased dramatically. Thus, Gpat2 is expressed at a specific stage of spermatogenesis, consistent with piRNA synthesis and meiosis I prophase, and its on-off expression pattern responds predominantly to epigenetic modifications.


Assuntos
Metilação de DNA/fisiologia , Epigênese Genética/fisiologia , Glicerol-3-Fosfato O-Aciltransferase/metabolismo , Prófase Meiótica I/fisiologia , Estágio Paquíteno/fisiologia , Regiões Promotoras Genéticas/fisiologia , Espermatócitos/metabolismo , Espermatogênese/fisiologia , Animais , Glicerol-3-Fosfato O-Aciltransferase/genética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Espermatócitos/citologia
9.
Sci Technol Adv Mater ; 17(1): 177-187, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27877868

RESUMO

A facile synthetic approach to prepare porous ZnO@CuNi hybrid films is presented. Initially, magnetic CuNi porous layers (consisting of phase separated CuNi alloys) are successfully grown by electrodeposition at different current densities using H2 bubbles as a dynamic template to generate the porosity. The porous CuNi alloys serve as parent scaffolds to be subsequently filled with a solution containing ZnO nanoparticles previously synthesized by sol-gel. The dispersed nanoparticles are deposited dropwise onto the CuNi frameworks and the solvent is left to evaporate while the nanoparticles impregnate the interior of the pores, rendering ZnO-coated CuNi 3D porous structures. No thermal annealing is required to obtain the porous films. The synthesized hybrid porous layers exhibit an interesting combination of tunable ferromagnetic and photoluminescent properties. In addition, the aqueous photocatalytic activity of the composite is studied under UV-visible light irradiation for the degradation of Rhodamine B. The proposed method represents a fast and inexpensive approach towards the implementation of devices based on metal-semiconductor porous systems, avoiding the use of post-synthesis heat treatment steps which could cause deleterious oxidation of the metallic counterpart, as well as collapse of the porous structure and loss of the ferromagnetic properties.

10.
Microsc Microanal ; 20(3): 698-705, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24750576

RESUMO

Physicochemical properties of transition metal oxides are directly determined by the oxidation state of the metallic cations. To address the increasing need to accurately evaluate the oxidation states of transition metal oxide systems at the nanoscale, here we present "Oxide Wizard." This script for Digital Micrograph characterizes the energy-loss near-edge structure and the position of the transition metal edges in the electron energy-loss spectrum. These characteristics of the edges can be linked to the oxidation states of transition metals with high spatial resolution. The power of the script is demonstrated by mapping manganese oxidation states in Fe3O4/Mn3O4 core/shell nanoparticles with sub-nanometer resolution in real space.

11.
Sci Technol Adv Mater ; 15(3): 035015, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27877691

RESUMO

The microstructure and mechanical properties of Zr48Cu48 - x Al4M x (M ≡ Fe or Co, x = 0, 0.5, 1 at.%) metallic glass (MG) composites are highly dependent on the amount of Fe or Co added as microalloying elements in the parent Zr48Cu48Al4 material. Addition of Fe and Co promotes the transformation from austenite to martensite during the course of nanoindentation or compression experiments, resulting in an enhancement of plasticity. However, the presence of Fe or Co also reduces the glass forming ability, ultimately causing a worsening of the mechanical properties. Owing to the interplay between these two effects, the compressive plasticity for alloys with x = 0.5 (5.5% in Zr48Cu47.5Al4Co0.5 and 6.2% in Zr48Cu47.5Al4Fe0.5) is considerably larger than for Zr48Cu48Al4 or the alloys with x = 1. Slight variations in the Young's modulus (around 5-10%) and significant changes in the yield stress (up to 25%) are also observed depending on the composition. The different microstructural factors that have an influence on the mechanical behavior of these composites are investigated in detail: (i) co-existence of amorphous and crystalline phases in the as-cast state, (ii) nature of the crystalline phases (austenite versus martensite content), and (iii) propensity for the austenite to undergo a mechanically-driven martensitic transformation during plastic deformation. Evidence for intragranular nanotwins likely generated in the course of the austenite-martensite transformation is provided by transmission electron microscopy. Our results reveal that fine-tuning of the composition of the Zr-Cu-Al-(Fe,Co) system is crucial in order to optimize the mechanical performance of these bulk MG composites, to make them suitable materials for structural applications.

12.
Mol Cell Biochem ; 377(1-2): 197-205, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23456478

RESUMO

Reverse cholesterol transport is a process of high antiatherogenic relevance in which apolipoprotein AI (apoA-I) plays an important role. The interaction of apoA-I with peripheral cells produces through mechanisms that are still poorly understood the mobilization of intracellular cholesterol depots toward plasma membrane. In macrophages, these mechanisms seem to be related to the modulation of the activity of acyl-CoA cholesterol acyltransferase (ACAT), the enzyme responsible for the intracellular cholesterol ester biosynthesis that is stored in lipid droplets. The activation of ACAT and the accumulation of lipid droplets play a key role in the transformation of macrophages into foam cells, leading to the formation of atheroma or atherosclerotic plaque. ApoA-I Helsinki (or ∆K107) is a natural apoA-I variant with a lysine deletion in the central protein region, carriers of which have increased atherosclerosis risk. We herein show that treatment of cultured RAW macrophages or CHOK1 cells with ∆K107, but not with wild-type apoA-I or a variant containing a similar deletion at the C-terminal region (∆K226), lead to a marked increase (more than 10 times) in the intracellular ACAT1 protein level as detected by western blot analysis. However, we could only detect a slight increase in cholesteryl ester produced by ∆K107 mainly when Chol loading was supplied by low-density lipoprotein (LDL). Although a similar choline-phospholipid efflux is evoked by these apoA-I variants, the change in phosphatidylcholine/sphyngomyelin distribution produced by wild-type apoA-I is not observed with either ∆K107 or ∆K226.


Assuntos
Acetil-CoA C-Acetiltransferase/metabolismo , Apolipoproteína A-I/fisiologia , Acetil-CoA C-Acetiltransferase/genética , Animais , Linhagem Celular , Membrana Celular/metabolismo , Sobrevivência Celular , Colesterol/metabolismo , Ésteres do Colesterol/metabolismo , LDL-Colesterol/fisiologia , Expressão Gênica , Humanos , Camundongos , Fosfolipídeos/metabolismo , Triglicerídeos/metabolismo
13.
Acta Odontol Latinoam ; 26(2): 97-103, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24303733

RESUMO

The potential for bone repair is influenced by various biochemical, biomechanical, hormonal, and pathological mechanisms and factors such as diet and its components, all of which govern the behavior and function of the cells responsible for forming new bone. Several authors suggest that a high sucrose diet could change the calcium balance and bone composition in animals, altering hard tissue mineralization. The mechanism by which it occurs is unclear. Alveolar healing following tooth extraction has certain characteristics making this type of wound unique, in both animals and humans. The general aim of this study was to evaluate and quantify the biological response during alveolar healing following tooth extraction in rats fed on high sucrose diets, by means of osteocyte lacunae histomorphometry, counting empty lacunae and measuring areas of bone quiescence, formation and resorption. Forty-two Wistar rats of both sexes were divided into two groups: an experimental group fed on modified Stephan Harris diet (43% sucrose) and a control group fed on standard balanced diet. The animals were anesthetized and their left and right lower molars extracted. They were killed at 0 hours, 14, 28, 60 and 120 days. Samples were fixed, decalcified in EDTA and embedded in paraffin to prepare sections for optical microscopy which were stained with hematoxylin/eosin. Histomorphometric analysis showed significant differences in the size of osteocyte lacunae between groups at 28 and 60 days, with the experimental group having larger lacunae. There were more empty lacunae in the experimental group at 14 days, and no significant difference in the areas of bone activity. A high sucrose diet could modify the morphology and quality of bone tissue formed in the alveolus following tooth extraction.


Assuntos
Processo Alveolar , Sacarose Alimentar/administração & dosagem , Extração Dentária , Cicatrização , Animais , Dieta , Feminino , Masculino , Ratos , Ratos Wistar
14.
Small ; 8(10): 1498-502, 2012 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-22411925

RESUMO

Hybrid magnetic phospholipidic-based tubular and helical microagents are wirelessly manipulated by means of a 5-DOF electromagnetic system. Two different strategies are used to manipulate these nanostructures in simulated biologic capillaries. Tubules are pulled by applying magnetic field gradients and oriented by magnetic fields. Helices exhibit a cork-screw motion similar to the swimming strategy used by motile bacteria such as E. coli.


Assuntos
Ligas/química , Galvanoplastia/métodos , Lipídeos/química , Magnetismo/métodos , Metais/química , Tecnologia sem Fio , Magnetometria , Microscopia Eletrônica de Varredura , Vibração
15.
Org Biomol Chem ; 10(9): 1807-19, 2012 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-22249177

RESUMO

ß-Carbolines (ßCs) are a group of alkaloids present in many plants and animals. It has been suggested that these alkaloids participate in a variety of significant photosensitized processes. Despite their well-established natural occurrence, the main biological role of these alkaloids and the mechanisms involved are, to date, poorly understood. In the present work, we examined the capability of three important ßCs (norharmane, harmane and harmine) and two of its derivatives (N-methyl-norharmane and N-methyl-harmane) to induce DNA damage upon UV-A excitation, correlating the type and extent of the damage with the photophysical characteristics and DNA binding properties of the compounds. The results indicate that DNA damage is mostly mediated by a direct type-I photoreaction of the protonated ßCs after non-intercalative electrostatic binding. Reactive oxygen species such as singlet oxygen and superoxide are not involved to a major extent, as indicated by the only small influence of D(2)O and of superoxide dismutase on damage generation. An analysis with repair enzymes revealed that oxidative purine modifications such as 8-oxo-7,8-dihydroguanine, sites of base loss and single-strand breaks (SSB) are generated by all ßCs, while only photoexcited harmine gives rise to the formation of cyclobutane pyrimidine dimers as well.


Assuntos
Carbolinas/química , DNA/química , Fármacos Fotossensibilizantes/química , Cinética , Estrutura Molecular , Processos Fotoquímicos , Espécies Reativas de Oxigênio , Timidina/química
16.
Front Endocrinol (Lausanne) ; 13: 849279, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35574033

RESUMO

Gliomas are the most frequent solid tumors in children. Among these, high-grade gliomas are less common in children than in adults, though they are similar in their aggressive clinical behavior. In adults, glioblastoma is the most lethal tumor of the central nervous system. Insulin-like growth factor 1 receptor (IGF1R) plays an important role in cancer biology, and its nuclear localization has been described as an adverse prognostic factor in different tumors. Previously, we have demonstrated that, in pediatric gliomas, IGF1R nuclear localization is significantly associated with high-grade tumors, worst clinical outcome, and increased risk of death. Herein we explore the role of IGF1R intracellular localization by comparing two glioblastoma cell lines that differ only in their IGF1R capacity to translocate to the nucleus. In vitro, IGF1R nuclear localization enhances glioblastoma cell motility and metabolism without affecting their proliferation. In vivo, IGF1R has the capacity to translocate to the nucleus and allows not only a higher proliferation rate and the earlier development of tumors but also renders the cells sensitive to OSI906 therapy. With this work, we provide evidence supporting the implications of the presence of IGF1R in the nucleus of glioma cells and a potential therapeutic opportunity for patients harboring gliomas with IGF1R nuclear localization.


Assuntos
Glioblastoma , Glioma , Adulto , Carcinogênese/metabolismo , Núcleo Celular/metabolismo , Criança , Glioblastoma/metabolismo , Glioma/metabolismo , Humanos , Receptores de Somatomedina/metabolismo
17.
J Am Chem Soc ; 133(42): 16738-41, 2011 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-21973012

RESUMO

Magnetic multilayered, onion-like, heterostructured nanoparticles are interesting model systems for studying magnetic exchange coupling phenomena. In this work, we synthesized heterostructured magnetic nanoparticles composed of two, three, or four components using iron oxide seeds for the subsequent deposition of manganese oxide. The MnO layer was allowed either to passivate fully in air to form an outer layer of Mn(3)O(4) or to oxidize partially to form MnO|Mn(3)O(4) double layers. Through control of the degree of passivation of the seeds, particles with up to four different magnetic layers can be obtained (i.e., FeO|Fe(3)O(4)|MnO|Mn(3)O(4)). Magnetic characterization of the samples confirmed the presence of the different magnetic layers.

18.
Atherosclerosis ; 316: 1-7, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33260006

RESUMO

BACKGROUND AND AIMS: The transition of macrophage to foam cells is a major hallmark of early stage atherosclerotic lesions. This process is characterized by the accumulation of large cytoplasmic lipid droplets containing large quantities of cholesterol esters (CE), triacylglycerol (TAG) and phospholipid (PL). Although cholesterol and CE metabolism during foam cell formation has been broadly studied, little is known about the role of the glycerolipids (TAG and PL) in this context. Here we studied the contribution of glycerolipid synthesis to lipid accumulation, focusing specifically on the first and rate-limiting enzyme of the pathway: glycerol-3-phosphate acyltransferase (GPAT). METHODS: We used RAW 264.7 cells and bone marrow derived macrophages (BMDM) treated with oxidized LDL (oxLDL). RESULTS: We showed that TAG synthesis is induced during the macrophage to foam cell transition. The expression and activity of GPAT3 and GPAT4 also increased during this process, and these two isoforms were required for the accumulation of cell TAG and PL. Compared to cells from wildtype mice after macrophage to foam cell transition, Gpat4-/- BMDM released more pro-inflammatory cytokines and chemokines, suggesting that the activity of GPAT4 could be associated with a decrease in the inflammatory response, probably by sequestering signaling precursors into lipid droplets. CONCLUSIONS: Our results provide evidence that TAG synthesis directed by GPAT3 and GPAT4 is required for lipid droplet formation and the modulation of the inflammatory response during the macrophage-foam cell transition.


Assuntos
Células Espumosas , Gotículas Lipídicas , 1-Acilglicerol-3-Fosfato O-Aciltransferase/genética , Animais , Glicerol , Glicerol-3-Fosfato O-Aciltransferase/genética , Lipoproteínas LDL , Macrófagos , Camundongos , Fosfatos , Triglicerídeos
19.
Biochimie ; 186: 43-50, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33865903

RESUMO

Metal ions and metal complexes are important components of nucleic acid biochemistry, participating both in regulation of gene expression and as therapeutic agents. Three new transition metal complexes of copper(II), zinc(II) and oxidovanadium(IV) with a ligand derived from o-vanillin and thiophene were previously synthesized and their antitumor properties were studied in our laboratory. To elucidate some molecular mechanisms tending to explain the cytotoxic effects observed over tumor cells, we investigated the interaction of these complexes with DNA by gel electrophoresis, UV-Vis spectroscopy, docking studies and molecular dynamics simulations. Our spectroscopy and computational results have shown that all of them were able to bind to DNA, Cu(II) complex is located in the minor groove while Zn(II) and oxidovanadium(IV) complexes act as major groove binding molecules. Interestingly, only the Cu(II) complex caused double-strand DNA nicks, consistent with its higher cytotoxic activities previously observed in tumor cell lines. We propose that the DNA-complex interaction destabilize the molecule either disrupting the phosphodiester bonds or impairing DNA replication, giving those complexes strong antitumor potential.


Assuntos
Cobre/química , DNA/química , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Vanadatos/química , Zinco/química , Bases de Schiff
20.
J Am Chem Soc ; 132(27): 9398-407, 2010 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-20568759

RESUMO

The magnetic properties of bimagnetic core/shell nanoparticles consisting of an antiferromagnetic MnO core and a ferrimagnetic passivation shell have been investigated. It is found that the phase of the passivation shell (gamma-Mn(2)O(3) or Mn(3)O(4)) depends on the size of the nanoparticles. Structural and magnetic characterizations concur that while the smallest nanoparticles have a predominantly gamma-Mn(2)O(3) shell, larger ones have increasing amounts of Mn(3)O(4). A considerable enhancement of the Néel temperature, T(N), and the magnetic anisotropy of the MnO core for decreasing core sizes has been observed. The size reduction also leads to other phenomena such as persistent magnetic moment in MnO up to high temperatures and an unusual temperature behavior of the magnetic domains.

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