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1.
Int J Mol Sci ; 25(17)2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39273113

RESUMO

Sodium tungstate (Na2WO4) normalizes glucose metabolism in the liver and muscle, activating the Mitogen-activated protein kinase/extracellular signal-regulated kinase (MAPK/ERK) pathway. Because this pathway controls neuronal survival and differentiation, we investigated the effects of Na2WO4 in mouse Neuro2a and human SH-SY5Y neuroblastoma monolayer cell cultures. Na2WO4 promotes differentiation to cholinergic neurites via an increased G1/G0 cell cycle in response to the synergic activation of the Phosphatidylinositol 3-kinase (PI3K/Akt) and ERK1/2 signaling pathways. In Neuro2a cells, Na2WO4 increases protein synthesis by activating the mechanistic target of rapamycin (mTOR) and S6K kinases and GLUT3-mediated glucose uptake, providing the energy and protein synthesis needed for neurite outgrowth. Furthermore, Na2WO4 increased the expression of myocyte enhancer factor 2D (MEF2D), a member of a family of transcription factors involved in neuronal survival and plasticity, through a post-translational mechanism that increases its half-life. Site-directed mutations of residues involved in the sumoylation of the protein abrogated the positive effects of Na2WO4 on the MEF2D-dependent transcriptional activity. In addition, the neuroprotective effects of Na2WO4 were evaluated in the presence of advanced glycation end products (AGEs). AGEs diminished neurite differentiation owing to a reduction in the G1/G0 cell cycle, concomitant with lower expression of MEF2D and the GLUT3 transporter. These negative effects were corrected in both cell lines after incubation with Na2WO4. These findings support the role of Na2WO4 in neuronal plasticity, albeit further experiments using 3D cultures, and animal models will be needed to validate the therapeutic potential of the compound.


Assuntos
Crescimento Neuronal , Fármacos Neuroprotetores , Compostos de Tungstênio , Humanos , Crescimento Neuronal/efeitos dos fármacos , Animais , Linhagem Celular Tumoral , Compostos de Tungstênio/farmacologia , Camundongos , Fármacos Neuroprotetores/farmacologia , Neuroproteção/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/metabolismo , Neuritos/metabolismo , Neuritos/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/efeitos dos fármacos
2.
Photochem Photobiol Sci ; 22(3): 487-501, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36402936

RESUMO

Harmaline (1) and harmalol (2) represent two 3,4-dihydro-ß-carboline (DHßCs) most frequently reported in a vast number of living systems. Fundamental aspects including the photosensitizing properties, cellular uptake, as well as the cyto- and phototoxicity of 1 and 2 were investigated herein. The molecular basis underlying the investigated processes are elucidated. Data reveal that both alkaloids show a distinctive pattern of extracellular DNA photodamage. Compound 1 induces a DNA photodamage profile dominated by oxidised purines and sites of base loss (AP sites), whereas 2 mostly induces single-strand breaks (SSBs) in addition to a small extent of purine oxidative damage. In both cases, DNA oxidative damage would occur through type I mechanism. In addition, a concerted hydrolytic attack is suggested as an extra mechanism accounting for the SSBs formation photoinduced by 2. Subcellular internalisation, cyto- and phototoxicity of 1 and 2 and the corresponding full-aromatic derivatives harmine (3) and harmol (4) also showed quite distinctive patterns in a structure-dependent manner. These results are discussed in the framework of the potential biological, biomedical and/or pharmacological roles reported for these alkaloids. The subtle structural difference (i.e., the exchange of a methoxy group for a hydroxyl substituent at C(7)) between harmaline and harmalol, gives rise to distinctive photosensitizing and subcellular localisation patterns.


Assuntos
Alcaloides , Harmalina , Harmalina/farmacologia , Harmalina/química , Carbolinas/farmacologia , Carbolinas/química , DNA
3.
Mar Drugs ; 19(1)2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33401388

RESUMO

Although Psychrobacter strain M9-54-1 had been previously isolated from the microbiota of holothurians and shown to degrade quorum sensing (QS) signal molecules C6 and C10-homoserine lactone (HSL), little was known about the gene responsible for this activity. In this study, we determined the whole genome sequence of this strain and found that the full 16S rRNA sequence shares 99.78-99.66% identity with Psychrobacter pulmonis CECT 5989T and P. faecalis ISO-46T. M9-54-1, evaluated using the agar well diffusion assay method, showed high quorum quenching (QQ) activity against a wide range of synthetic N-acylhomoserine lactone (AHLs) at 4, 15, and 28 °C. High-performance liquid chromatography-mass-spectrometry (HPLC-MS) confirmed that QQ activity was due to an AHL-acylase. The gene encoding for QQ activity in strain M9-54-1 was identified from its genome sequence whose gene product was named AhaP. Purified AhaP degraded substituted and unsubstituted AHLs from C4- to C14-HSL. Furthermore, heterologous expression of ahaP in the opportunistic pathogen Pseudomonas aeruginosa PAO1 reduced the expression of the QS-controlled gene lecA, encoding for a cytotoxic galactophilic lectin and swarming motility protein. Strain M9-54-1 also reduced brine shrimp mortality caused by Vibrio coralliilyticus VibC-Oc-193, showing potential as a biocontrol agent in aquaculture.


Assuntos
Amidoidrolases/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/patogenicidade , Psychrobacter/química , Percepção de Quorum/efeitos dos fármacos , Vibrio/efeitos dos fármacos , Vibrio/patogenicidade , Virulência/efeitos dos fármacos , 4-Butirolactona/análogos & derivados , 4-Butirolactona/metabolismo , Acil-Butirolactonas/metabolismo , Animais , Artemia , Genoma Bacteriano/genética , Estrutura Molecular , Psychrobacter/genética , RNA Ribossômico 16S
4.
Org Biomol Chem ; 18(33): 6519-6530, 2020 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-32628228

RESUMO

N-Methyl-ß-carboline (ßC) alkaloids, including normelinonine F (1b) and melinonine F (2b), have been found in a vast range of living species playing different biological, biomedical and/or pharmacological roles. Despite this, molecular bases of the mechanisms through which these alkaloids would exert their effect still remain unknown. Fundamental aspects including the photosensitizing properties and intracellular internalization of a selected group of N-methyl-ßC alkaloids were investigated herein. Data reveal that methylation of the ßC main ring enhances its photosensitizing properties either by increasing its binding affinity with DNA as a biomolecular target and/or by increasing its oxidation potential, in a structure-dependent manner. As a general rule, N(9)-substituted ßCs showed the highest photosensitizing efficiency. With the exception of 2-methyl-harminium, all the N-methyl-ßCs investigated herein induce a similar DNA photodamage profile, dominated largely by oxidized purines. This fact represents a distinctive behavior when comparing with N-unsubstituted-ßCs. On the other hand, although all the investigated compounds might accumulate mainly into the mitochondria of HeLa cells, methylation provides a distinctive dynamic pattern for mitochondrial uptake. While rapid (passive) diffusion is most probably reponsible for the prompt uptake/release of neutral ßCs, an active transport appears to mediate the (reatively slow) uptake of the quaternary cationic ßCs. This might be a consequence of a distinctive subcellular localization (mitochondrial membrane and/or matrix) or interaction with intracellular components. Biomedical and biotechnological implications are also discussed herein.


Assuntos
Carbolinas
5.
Int J Mol Sci ; 21(14)2020 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-32708806

RESUMO

In recent years, the prevalence of amyloid neurodegenerative diseases such as Alzheimer's disease (AD) has significantly increased in developed countries due to increased life expectancy. This amyloid disease is characterized by the presence of accumulations and deposits of ß-amyloid peptide (Aß) in neuronal tissue, leading to the formation of oligomers, fibers, and plaques. First, oligomeric intermediates that arise during the aggregation process are currently thought to be primarily responsible for cytotoxicity in cells. This work aims to provide further insights into the mechanisms of cytotoxicity by studying the interaction of Aß aggregates with Neuro-2a (N2a) neuronal cells and the effects caused by this interaction. For this purpose, we have exploited the advantages of advanced, multidimensional fluorescence microscopy techniques to determine whether different types of Aß are involved in higher rates of cellular toxicity, and we measured the cellular stress caused by such aggregates by using a fluorogenic intracellular biothiol sensor. Stress provoked by the peptide is evident by N2a cells generating high levels of biothiols as a defense mechanism. In our study, we demonstrate that Aß aggregates act as seeds for aggregate growth upon interacting with the cellular membrane, which results in cell permeability and damage and induces lysis. In parallel, these damaged cells undergo a significant increase in intracellular biothiol levels.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Membrana Celular/metabolismo , Neurônios/metabolismo , Agregação Patológica de Proteínas/metabolismo , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Animais , Linhagem Celular , Membrana Celular/patologia , Permeabilidade da Membrana Celular , Camundongos , Neurônios/patologia , Agregados Proteicos , Agregação Patológica de Proteínas/patologia
6.
Sensors (Basel) ; 18(1)2018 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-29315248

RESUMO

The development of new fluorescent probes for cellular imaging is currently a very active field because of the large potential in understanding cell physiology, especially targeting anomalous behaviours due to disease. In particular, red-emitting dyes are keenly sought, as the light in this spectral region presents lower interferences and a deeper depth of penetration in tissues. In this work, we have synthesized a red-emitting, dual probe for the multiplexed intracellular detection of biothiols and phosphate ions. We have prepared a fluorogenic construct involving a silicon-substituted fluorescein for red emission. The fluorogenic reaction is selectively started by the presence of biothiols. In addition, the released fluorescent moiety undergoes an excited-state proton transfer reaction promoted by the presence of phosphate ions, which modulates its fluorescence lifetime, τ, with the total phosphate concentration. Therefore, in a multidimensional approach, the intracellular levels of biothiols and phosphate can be detected simultaneously using a single fluorophore and with spectral clearing of cell autofluorescence interferences. We have applied this concept to different cell lines, including photoreceptor cells, whose levels of biothiols are importantly altered by light irradiation and other oxidants.


Assuntos
Fosfatos/análise , Fluoresceína , Corantes Fluorescentes , Prótons , Espectrometria de Fluorescência
7.
Chemistry ; 21(42): 14772-9, 2015 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-26374264

RESUMO

The simultaneous detection of relevant metabolites in living organisms by using one molecule introduces an approach to understanding the relationships between these metabolites in healthy and deregulated cells. Fluorescent probes of low toxicity are remarkable tools for this type of analysis of biological systems in vivo. As a proof of concept, different naturally occurring compounds, such as biothiols and phosphate anions, were the focus for this work. The 2,4-dinitrobenzenesulfinate (DNBS) derivative of 9-[1-(4-tert-butyl-2-methoxyphenyl)]-6-hydroxy-3H-xanthen-3-one (Granada Green; GG) were designed and synthesized. This new sulfinyl xanthene derivative can act as a dual sensor for the aforementioned analytes simultaneously. The mechanism of action of this derivative implies thiolysis of the sulfinyl group of the weakly fluorescent DNBS-GG by biological thiols at near-neutral pH values, thus releasing the fluorescent GG moiety, which simultaneously responds to phosphate anions through its fluorescence-decay time. The new dual probe was tested in solution by using steady-state and time-resolved fluorescence and intracellularly by using fluorescence-lifetime imaging microscopy (FLIM) in human epithelioid cervix carcinoma (HeLa) cells.


Assuntos
Corantes Fluorescentes/química , Nitrocompostos/química , Fosfatos/química , Compostos de Sulfidrila/química , Compostos de Sulfônio/química , Neoplasias do Colo do Útero/química , Xantenos/química , Xantinas/química , Feminino , Fluorescência , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Microscopia de Fluorescência , Estrutura Molecular , Fosfatos/análise , Compostos de Sulfidrila/análise
8.
Biosensors (Basel) ; 14(9)2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39329799

RESUMO

This research explores the use of the pepN activity fluorescent sensor DCM-Ala in bacterial biofilms, emphasizing its significance due to the critical role of biofilms in various biological processes. Advanced imaging techniques were employed to visualize pepN activity, introducing a novel approach to examining biofilm maturity. We found that the overexpression of pepN increases the ability of E. coli to form biofilm. The findings demonstrate varying levels of pepN activity throughout biofilm development, suggesting potential applications in biofilm research and management. The results indicate that the fluorescent emission from this sensor could serve as a reliable indicator of biofilm maturity, and the imaging techniques developed could enhance our understanding and control of biofilm-related processes. This work highlights the importance of innovative methods in biofilm study and opens new avenues for utilizing chemical emissions in biofilm management.


Assuntos
Biofilmes , Técnicas Biossensoriais , Escherichia coli , Corantes Fluorescentes
9.
Nutrients ; 15(22)2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-38004100

RESUMO

Skeletal muscle is the key tissue for maintaining protein and glucose homeostasis, having a profound impact on the development of diabetes. Diabetes causes deleterious changes in terms of loss of muscle mass, which will contribute to reduced glucose uptake and therefore progression of the disease. Nutritional approaches in diabetes have been directed to increase muscle glucose uptake, and improving protein turnover has been at least partially an oversight. In muscle, ß-hydroxy ß-methyl butyrate (HMB) promotes net protein synthesis, while arginine and lysine increase glucose uptake, albeit their effects on promoting protein synthesis are limited. This study evaluates if the combination of HMB, lysine, and arginine could prevent the loss of muscle mass and function, reducing the progression of diabetes. Therefore, the combination of these ingredients was tested in vitro and in vivo. In muscle cell cultures, the supplementation enhances glucose uptake and net protein synthesis due to an increase in the amount of GLUT4 transporter and stimulation of the insulin-dependent signaling pathway involving IRS-1 and Akt. In vivo, using a rat model of diabetes, the supplementation increases lean body mass and insulin sensitivity and decreases blood glucose and serum glycosylated hemoglobin. In treated animals, an increase in GLUT4, creatine kinase, and Akt phosphorylation was detected, demonstrating the synergic effects of the three ingredients. Our findings showed that nutritional formulations based on the combination of HMB, lysine, and arginine are effective, not only to control blood glucose levels but also to prevent skeletal muscle atrophy associated with the progression of diabetes.


Assuntos
Diabetes Mellitus , Lisina , Ratos , Animais , Lisina/farmacologia , Lisina/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Glicemia/metabolismo , Arginina/farmacologia , Arginina/metabolismo , Músculo Esquelético/metabolismo , Diabetes Mellitus/metabolismo , Glucose/metabolismo , Insulina/metabolismo , Suplementos Nutricionais
10.
Nutrients ; 14(7)2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-35406056

RESUMO

Extracellular vesicles are membrane-enclosed secreted vesicles involved in cell-to-cell communication processes, identified in virtually all body fluids. Among extracellular vesicles, exosomes have gained increasing attention in recent years as they have unique biological origins and deliver different cargos, such as nucleic acids, proteins, and lipids, which might mediate various health processes. In particular, milk-derived exosomes are proposed as bioactive compounds of breast milk, which have been reported to resist gastric digestion and reach systemic circulation, thus being bioavailable after oral intake. In the present manuscript, we critically discuss the available evidence on the health benefits attributed to milk exosomes, and we provide an outlook for the potential future uses of these compounds. The use of milk exosomes as bioactive ingredients represents a novel avenue to explore in the context of human nutrition, and they might exert important beneficial effects at multiple levels, including but not limited to intestinal health, bone and muscle metabolism, immunity, modulation of the microbiota, growth, and development.


Assuntos
Exossomos , Vesículas Extracelulares , MicroRNAs , Microbiota , Animais , Exossomos/metabolismo , Vesículas Extracelulares/metabolismo , Feminino , Humanos , MicroRNAs/metabolismo , Leite/metabolismo , Leite Humano/metabolismo
11.
Front Nutr ; 9: 992682, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36532542

RESUMO

Introduction: The main cause of insulin resistance in childhood is obesity, which contributes to future comorbidities as in adults. Although high-calorie diets and lack of exercise contribute to metabolic disease development, food quality rather than the quantity of macronutrients is more important than food density. The purpose of the present study was to examine the effects of changing the quality of carbohydrates from rapidly to slowly digestible carbohydrates on the composition of the gut microbiota and the profiles of the functional pathways in growing rats with obesity due to a high-fat diet (HFD). Methods: During the course of 4 weeks, rats growing on an HFD-containing carbohydrates with different digestive rates were fed either HFD-containing carbohydrates with a rapid digestion rate (OBE group) or HFD-containing carbohydrates with a slow digestion rate (OBE-ISR group). A non-obese group (NOB) was included as a reference, and rats were fed on a rodent standard diet (AIN93G). An analysis of gut microbiota was conducted using 16S rRNA-based metagenomics; a linear mixed-effects model (LMM) was used to determine changes in abundance between baseline and 4 weeks of treatment, and functional pathways were identified. Gut microbiota composition at bacterial diversity and relative abundance, at phylum and genus levels, and functional profiles were analyzed by integrating the Integrated Microbial Genomes (IMG) database. Results: The groups showed comparable gut microbiota at baseline. At the end of the treatment, animals from the ISR group exhibited differences at the phylum levels by decreasing the diversity of Fisher's index and Firmicutes (newly named as Bacillota), and increasing the Pielou's evenness and Bacteroidetes (newly named as Bacteroidota); at the genus level by increasing Alistipes, Bifidobacterium, Bacteroides, Butyricimonas, Lachnoclostridium, Flavonifractor, Ruminiclostridium 5, and Faecalibaculum and decreasing Muribaculum, Blautia, and Ruminiclostridium 9. Remarkably, relative abundances of genera Tyzzerella and Angelakisella were higher in the OBE group compared to NOB and OBE-ISR groups. In addition, some microbiota carbohydrate metabolism pathways such as glycolysis, glucuronic acid degradation, pentose phosphate pathway, methanogenesis, and fatty acid biosynthesis exhibited increased activity in the OBE-ISR group after the treatment. Higher levels of acetate and propionate were found in the feces of the ISR group compared with the NOB and OBE groups. Conclusion: The results of this study demonstrate that replacing rapidly digestible carbohydrates with slowly digestible carbohydrates within an HFD improve the composition of the gut microbiota. Consequently, metabolic disturbances associated with obesity may be prevented.

12.
Front Nutr ; 9: 809865, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35425792

RESUMO

Childhood obesity prevention is important to avoid obesity and its comorbidities into adulthood. Although the energy density of food has been considered a main obesogenic factor, a focus on food quality rather that the quantity of the different macronutrients is needed. Therefore, this study investigates the effects of changing the quality of carbohydrates from rapidly to slowly digestible carbohydrates on metabolic abnormalities and its impact on obesity in growing rats fed a high-fat diet (HFD). Growing rats were fed on HFD containing carbohydrates with different digestion rates: a HFD containing rapid-digesting carbohydrates (OBE group) or slow-digesting carbohydrates (ISR group), for 4 weeks and the effect on the metabolism and signaling pathways were analyzed in different tissues. Animals from OBE group presented an overweight/obese phenotype with a higher body weight gain and greater accumulation of fat in adipose tissue and liver. This state was associated with an increase of HOMA index, serum diacylglycerols and triacylglycerides, insulin, leptin, and pro-inflammatory cytokines. In contrast, the change of carbohydrate profile in the diet to one based on slow digestible prevented the obesity-related adverse effects. In adipose tissue, GLUT4 was increased and UCPs and PPARγ were decreased in ISR group respect to OBE group. In liver, GLUT2, FAS, and SRBP1 were lower in ISR group than OBE group. In muscle, an increase of glycogen, GLUT4, AMPK, and Akt were observed in comparison to OBE group. In conclusion, this study demonstrates that the replacement of rapidly digestible carbohydrates for slowly digestible carbohydrates within a high-fat diet promoted a protective effect against the development of obesity and its associated comorbidities.

13.
ACS Sens ; 6(7): 2563-2573, 2021 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-34148347

RESUMO

A new chloride-sensitive red fluorescent protein derived from Entacmaea quadricolor is described. We found that mBeRFP exhibited moderate sensitivity to chloride and, via site-directed mutagenesis (S94V and R205Y), we increased the chloride affinity by more than an order of magnitude (kd = 106 ± 6 mM) at physiological pH. In addition, cis-trans isomerization of the chromophore produces a dual emission band with different chloride sensitivities, which allowed us to develop a ratiometric methodology to measure intracellular chloride concentrations.


Assuntos
Cloretos , Concentração de Íons de Hidrogênio , Proteínas Luminescentes/genética , Mutagênese Sítio-Dirigida , Proteína Vermelha Fluorescente
14.
Eur J Med Chem ; 220: 113470, 2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-33940464

RESUMO

We have recently reported on the development and trypanocidal activity of a class of inhibitors of Trypanosome Alternative Oxidase (TAO) that are targeted to the mitochondrial matrix by coupling to lipophilic cations via C14 linkers to enable optimal interaction with the enzyme's active site. This strategy resulted in a much-enhanced anti-parasite effect, which we ascribed to the greater accumulation of the compound at the location of the target protein, i.e. the mitochondrion, but to date this localization has not been formally established. We therefore synthesized a series of fluorescent analogues to visualize accumulation and distribution within the cell. The fluorophore chosen, julolidine, has the remarkable extra feature of being able to function as a viscosity sensor and might thus additionally act as a probe of the cellular glycerol that is expected to be produced when TAO is inhibited. Two series of fluorescent inhibitor conjugates incorporating a cationic julolidine-based viscosity sensor were synthesized and their photophysical and biological properties were studied. These probes display a red emission, with a high signal-to-noise ratio (SNR), using both single- and two-photon excitation. Upon incubation with T. brucei and mammalian cells, the fluorescent inhibitors 1a and 2a were taken up selectively in the mitochondria as shown by live-cell imaging. Efficient partition of 1a in functional isolated (rat liver) mitochondria was estimated to 66 ± 20% of the total. The compounds inhibited recombinant TAO enzyme in the submicromolar (1a, 2c, 2d) to low nanomolar range (2a) and were effective against WT and multidrug-resistant trypanosome strains (B48, AQP1-3 KO) in the submicromolar range. Good selectivity (SI > 29) over mammalian HEK cells was observed. However, no viscosity-related shift could be detected, presumably because the glycerol was produced cytosolically, and released through aquaglyceroporins, whereas the probe was located, virtually exclusively, in the trypanosome's mitochondrion.


Assuntos
Inibidores Enzimáticos/farmacologia , Corantes Fluorescentes/farmacologia , Proteínas Mitocondriais/antagonistas & inibidores , Oxirredutases/antagonistas & inibidores , Proteínas de Plantas/antagonistas & inibidores , Trypanosoma brucei brucei/efeitos dos fármacos , Trypanosoma/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Teoria da Densidade Funcional , Relação Dose-Resposta a Droga , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/química , Células HEK293 , Humanos , Microscopia de Fluorescência , Proteínas Mitocondriais/metabolismo , Estrutura Molecular , Imagem Óptica , Oxirredutases/metabolismo , Proteínas de Plantas/metabolismo , Relação Estrutura-Atividade , Trypanosoma/enzimologia , Trypanosoma brucei brucei/enzimologia
15.
Nutrients ; 12(9)2020 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-32854204

RESUMO

A nutritional growth retardation study, which closely resembles the nutritional observations in children who consumed insufficient total energy to maintain normal growth, was conducted. In this study, a nutritional stress in weanling rats placed on restricted balanced diet for 4 weeks is produced, followed by a food recovery period of 4 weeks using two enriched diets that differ mainly in the slow (SDC) or fast (RDC) digestibility and complexity of their carbohydrates. After re-feeding with the RDC diet, animals showed the negative effects of an early caloric restriction: an increase in adiposity combined with poorer muscle performance, insulin resistance and, metabolic inflexibility. These effects were avoided by the SDC diet, as was evidenced by a lower adiposity associated with a decrease in fatty acid synthase expression in adipose tissue. The improved muscle performance of the SDC group was based on an increase in myocyte enhancer factor 2D (MEF2D) and creatine kinase as markers of muscle differentiation as well as better insulin sensitivity, enhanced glucose uptake, and increased metabolic flexibility. In the liver, the SDC diet promoted glycogen storage and decreased fatty acid synthesis. Therefore, the SDC diet prevents the catch-up fat phenotype through synergistic metabolic adaptations in adipose tissue, muscle, and liver. These coordinated adaptations lead to better muscle performance and a decrease in the fat/lean ratio in animals, which could prevent long-term negative metabolic alterations such as obesity, insulin resistance, dyslipidemia, and liver fat deposits later in life.


Assuntos
Tecido Adiposo/metabolismo , Adiposidade , Carboidratos da Dieta/administração & dosagem , Fígado/metabolismo , Músculo Esquelético/metabolismo , Animais , Digestão , Metabolismo Energético , Glucose/metabolismo , Crescimento , Resistência à Insulina , Masculino , Distúrbios Nutricionais , Ratos Wistar , Aumento de Peso
16.
Nutrients ; 12(2)2020 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-32092940

RESUMO

Skeletal muscle plays a relevant role in metabolic flexibility and fuel usage and the associated muscle metabolic inflexibility due to high-fat diets contributing to obesity and type 2 diabetes. Previous research from our group indicates that a high-fat and rapid-digesting carbohydrate diet during pregnancy promotes an excessive adipogenesis and also increases the risk of non-alcoholic fatty liver disease in the offspring. This effect can be counteracted by diets containing carbohydrates with similar glycemic load but lower digestion rates. To address the role of the skeletal muscle in these experimental settings, pregnant rats were fed high-fat diets containing carbohydrates with similar glycemic load but different digestion rates, a high fat containing rapid-digesting carbohydrates diet (HF/RD diet) or a high fat containing slow-digesting carbohydrates diet (HF/SD diet). After weaning, male offspring were fed a standard diet for 3 weeks (weaning) or 10 weeks (adolescence) and the impact of the maternal HF/RD and HF/SD diets on the metabolism, signaling pathways and muscle transcriptome was analyzed. The HF/SD offspring displayed better muscle features compared with the HF/RD group, showing a higher muscle mass, myosin content and differentiation markers that translated into a greater grip strength. In the HF/SD group, metabolic changes such as a higher expression of fatty acids (FAT/CD36) and glucose (GLUT4) transporters, an enhanced glycogen content, as well as changes in regulatory enzymes such as muscle pyruvate kinase and pyruvate dehydrogenase kinase 4 were found, supporting an increased muscle metabolic flexibility and improved muscle performance. The analysis of signaling pathways was consistent with a better insulin sensitivity in the muscle of the HF/SD group. Furthermore, increased expression of genes involved in pathways leading to muscle differentiation, muscle mass regulation, extracellular matrix content and insulin sensitivity were detected in the HF/SD group when compared with HF/RD animals. In the HF/SD group, the upregulation of the ElaV1/HuR gene could be one of the main regulators in the positive effects of the diet in early programming on the offspring. The long-lasting programming effects of the HF/SD diet during pregnancy may depend on a coordinated gene regulation, modulation of signaling pathways and metabolic flexibility that lead to an improved muscle functionality. The dietary early programming associated to HF/SD diet has synergic and positive crosstalk effects in several tissues, mainly muscle, liver and adipose tissue, contributing to maintain the whole body homeostasis in the offspring.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Carboidratos da Dieta/farmacologia , Fenômenos Fisiológicos da Nutrição Materna , Músculo Esquelético/metabolismo , Maleabilidade , Tecido Adiposo/metabolismo , Animais , Dieta Hiperlipídica/métodos , Digestão , Feminino , Perfilação da Expressão Gênica , Carga Glicêmica , Fígado/metabolismo , Masculino , Gravidez , Ratos , Ratos Sprague-Dawley , Transdução de Sinais
17.
Org Biomol Chem ; 7(13): 2681-4, 2009 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-19532982

RESUMO

Gene delivery systems based on the beta-cyclodextrin scaffold have been synthesized by combining the copper(I)-catalyzed azide-alkyne coupling ("click chemistry") and an efficient acylation method of the secondary hydroxyls; molecular flexibility, charge density and hydrophobic-hydrophilic balance are critical parameters that can be fine-tuned by the click approach.


Assuntos
Técnicas de Transferência de Genes , Substâncias Macromoleculares/química , beta-Ciclodextrinas/química , Alcinos/química , Animais , Azidas/química , Células CHO , Catálise , Cobre/química , Cricetinae , Cricetulus , DNA/química , DNA/metabolismo , Substâncias Macromoleculares/síntese química , Substâncias Macromoleculares/metabolismo , Estrutura Molecular , Nanopartículas/química , Estereoisomerismo , beta-Ciclodextrinas/síntese química , beta-Ciclodextrinas/metabolismo
18.
Nutrients ; 11(4)2019 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-31013988

RESUMO

High-fat (HF) and rapid digestive (RD) carbohydrate diets during pregnancy promote excessive adipogenesis in offspring. This effect can be corrected by diets with similar glycemic loads, but low rates of carbohydrate digestion. However, the effects of these diets on metabolic programming in the livers of offspring, and the liver metabolism contributions to adipogenesis, remain to be addressed. In this study, pregnant insulin-resistant rats were fed high-fat diets with similar glycemic loads but different rates of carbohydrate digestion, High Fat-Rapid Digestive (HF-RD) diet or High Fat-Slow Digestive (HF-SD) diet. Offspring were fed a standard diet for 10 weeks, and the impact of these diets on the metabolic and signaling pathways involved in liver fat synthesis and storage of offspring were analyzed, including liver lipidomics, glycogen and carbohydrate and lipid metabolism key enzymes and signaling pathways. Livers from animals whose mothers were fed an HF-RD diet showed higher saturated triacylglycerol deposits with lower carbon numbers and double bond contents compared with the HF-SD group. Moreover, the HF-RD group exhibited enhanced glucose transporter 2, pyruvate kinase (PK), acetyl coenzyme A carboxylase (ACC) and fatty acid (FA) synthase expression, and a decrease in pyruvate carboxylase (PyC) expression leading to an altered liver lipid profile. These parameters were normalized in the HF-SD group. The changes in lipogenic enzyme expression were parallel to changes in AktPKB phosphorylation status and nuclear expression in carbohydrate-response element and sterol regulatory element binding proteins. In conclusion, an HF-RD diet during pregnancy translates to changes in liver signaling and metabolic pathways in offspring, enhancing liver lipid storage and synthesis, and therefore non-alcoholic fatty liver disease (NAFLD) risk. These changes can be corrected by feeding an HF-SD diet during pregnancy.


Assuntos
Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Metabolismo dos Carboidratos , Carboidratos da Dieta/metabolismo , Transportador de Glucose Tipo 2/metabolismo , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Animais , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/genética , Dieta Hiperlipídica , Digestão , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Transportador de Glucose Tipo 2/genética , Gravidez , Efeitos Tardios da Exposição Pré-Natal , Ratos , Ratos Sprague-Dawley , Fatores de Risco , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 2/genética , Proteína de Ligação a Elemento Regulador de Esterol 2/metabolismo
19.
Sci Rep ; 9(1): 1659, 2019 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-30733499

RESUMO

A xanthene derivative, Granada Green dinitrobenzene sulfonate (GGDNBS), has been synthesized to assay cellular oxidative stress based on changes in the concentration of biothiols. The dye is able to react with biological thiols by a thiolysis reaction that promotes a change in fluorescence intensity. To demonstrate the usefulness of GGDNBS for in vivo oxidative stress measurements, 661 W photoreceptor-derived cells were exposed to light to induce ROS generation, and changes in GGDNBS fluorescence were measured. In these cells, GGDNBS fluorescence was correlated with the biothiol levels measured by an enzymatic method. Therefore, GGDNBS allows us to monitor changes in the levels of biothiols associated with ROS generation via single-cell bioimaging.


Assuntos
Corantes Fluorescentes/química , Glutationa/metabolismo , Estresse Oxidativo , Espécies Reativas de Oxigênio/análise , Compostos de Sulfidrila/química , Células Hep G2 , Humanos , Oxirredução , Espécies Reativas de Oxigênio/metabolismo
20.
J Nutr Biochem ; 61: 183-196, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30253280

RESUMO

An obesogenic environment during pregnancy has been shown to increase the risk of dysregulation on adipogenesis and insulin resistance in the offspring. Being essential for the growing fetus, glucose supply is guaranteed by a number of modifications in the mother's metabolism, and thus, glucose control during pregnancy especially among obese or diabetic women is paramount to prevent adverse consequences in their children. Besides the election of low-glycemic-index carbohydrates, the rate of carbohydrate digestion could be relevant to keep a good glucose control. In the present study, we compared the effects of two high-fat diets with similar glycemic load but different rates of carbohydrate digestion given to pregnant insulin-resistant rats. After birth, all animals were fed a standard diet until age 14 weeks. We analyzed offspring body composition, plasma and adipocyte lipidomics, lipid metabolism in adipose tissue and insulin sensitivity. Those animals whose mothers were fed the rapid-digesting carbohydrate diet exhibited an excessive adipogenesis. Thus, these animals showed a marked lipidemia, increased lipid synthesis in the adipose tissue and reduced glucose transporter amount in the adipose. On the contrary, those animals whose mothers were fed the slow-digesting carbohydrate diet showed a profile in the measured parameters closer to that of the offspring of healthy mothers. These results support the hypothesis that not only glycemic index but the rate of carbohydrate digestion during gestation may be critical to regulate the programming of adipogenesis in the offspring.


Assuntos
Adipogenia/fisiologia , Carboidratos/farmacocinética , Resistência à Insulina , Metabolismo dos Lipídeos , Fenômenos Fisiológicos da Nutrição Materna , Adipogenia/efeitos dos fármacos , Tecido Adiposo/metabolismo , Ração Animal , Animais , Composição Corporal/efeitos dos fármacos , Composição Corporal/fisiologia , Peso Corporal , Feminino , Lipídeos/sangue , Masculino , Gravidez , Ratos Sprague-Dawley
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