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1.
Endocr Connect ; 9(2): 90-100, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31905163

RESUMEN

OBJECTIVE: Insulin resistance is a major pathophysiological link between obesity and its metabolic complications. Weight loss (WL) is an effective tool to prevent obesity-related diseases; however, the mechanisms of an improvement in insulin sensitivity (IS) after weight-reducing interventions are not completely understood. The aim of the present study was to analyze the relationships between IS and adipose tissue (AT) expression of the genes involved in the regulation of lipolysis in obese subjects after WL. METHODS: Fifty-two obese subjects underwent weight-reducing dietary intervention program. The control group comprised 20 normal-weight subjects, examined at baseline only. Hyperinsulinemic-euglycemic clamp and s.c. AT biopsy with subsequent gene expression analysis were performed before and after the program. RESULTS: AT expression of genes encoding lipases (PNPLA2, LIPE and MGLL) and lipid-droplet proteins enhancing (ABHD5) and inhibiting lipolysis (PLIN1 and CIDEA) were decreased in obese individuals in comparison with normal-weight individuals. The group of 38 obese participants completed dietary intervention program and clamp studies, which resulted in a significant WL and an improvement in mean IS. However, in nine subjects from this group IS did not improve in response to WL. AT expression of PNPLA2, LIPE and PLIN1 increased only in the group without IS improvement. CONCLUSIONS: Excessive lipolysis may prevent an improvement in IS during WL. The change in AT PNPLA2 and LIPE expression was a negative predictor of the change in IS after WL.

2.
J Clin Endocrinol Metab ; 103(7): 2563-2570, 2018 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-29860500

RESUMEN

Context: We previously demonstrated that insulin infusion altered metabolite concentrations in cerebral tissues assessed with proton magnetic resonance spectroscopy (1H-MRS) in young subjects with high insulin sensitivity, but not in those with low insulin sensitivity. Fat overload is an important factor leading to insulin resistance. Objective: The purpose of the current study was to examine the effect of elevated circulating free fatty acid (FFA) levels on metabolites in cerebral tissues assessed with 1H-MRS. Design: The study group comprised 10 young, healthy male subjects. 1H-MRS was performed at baseline and after 4-hour Intralipid (Fresenius Kabi)/heparin or saline infusions administered in random order. Voxels were positioned in the left frontal lobe, left temporal lobe, and hippocampus. The ratios of N-acetylaspartate (NAA), choline (Cho)-containing compounds, myo-inositol (mI), and glutamate/glutamine/γ-aminobutyric acid complex (Glx) to creatine (Cr) and nonsuppressed water signal were determined. Results: Intralipid/heparin infusion resulted in a significant increase in circulating FFAs (P < 0.0001). Significant changes in brain neurometabolite concentrations in response to Intralipid/heparin infusion were increases in frontal mI/Cr (P = 0.041) and mI/H2O (P = 0.037), decreases in frontal and hippocampal Glx/Cr (P = 0.018 and P = 0.015, respectively) and Glx/H2O (P = 0.03 and P = 0.067, respectively), and a decrease in hippocampal NAA/Cr (P = 0.007) and NAA/H2O (P = 0.019). No changes in neurometabolites were observed during the saline infusion. Conclusions: Acute circulating FFA elevation influenced cerebral metabolites in healthy humans and lipid-induced insulin resistance could be partly responsible for these effects.


Asunto(s)
Anticoagulantes/administración & dosificación , Encéfalo/metabolismo , Emulsiones Grasas Intravenosas/administración & dosificación , Ácidos Grasos no Esterificados/metabolismo , Heparina/administración & dosificación , Fosfolípidos/administración & dosificación , Espectroscopía de Protones por Resonancia Magnética/métodos , Aceite de Soja/administración & dosificación , Adulto , Ácido Aspártico/análogos & derivados , Ácido Aspártico/análisis , Ácido Aspártico/metabolismo , Colina/análisis , Colina/metabolismo , Creatina/análisis , Creatina/metabolismo , Emulsiones/administración & dosificación , Ácidos Grasos no Esterificados/análisis , Lóbulo Frontal/metabolismo , Ácido Glutámico/análisis , Ácido Glutámico/metabolismo , Glutamina/análisis , Glutamina/metabolismo , Voluntarios Sanos , Hipocampo/metabolismo , Humanos , Inositol/análisis , Inositol/metabolismo , Masculino , Ácido gamma-Aminobutírico/análisis , Ácido gamma-Aminobutírico/metabolismo
3.
Endocrine ; 61(2): 275-284, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29737494

RESUMEN

PURPOSE: Obesity is characterized by insulin resistance and low-grade systemic and adipose tissue (AT) inflammation. It remains unclear whether beneficial effects of weight loss are related to AT inflammation. We aimed to assess the effect of weight loss during low-calorie diet on insulin sensitivity, AT expression of genes associated with inflammation in young subjects with obesity. Furthermore, we estimated the effects of immunomodulatory (1, 3)(1, 6)-ß-glucan (BG) on the above parameters. METHODS: The study group comprised 52 subjects with obesity. Twelve-week dietary intervention was applied, with randomization to receive or not 500 mg BG daily. Euglycemic hyperinsulinemic clamp, subcutaneous AT biopsy were performed before and after the program. Twenty normal-weight subjects, examined at baseline, served as a control group. RESULTS: At baseline, obese subjects had lower insulin sensitivity, lower AT ADIPOQ, JAK1, and JAK2 expression and higher AT expression of LEP, IL6ST, STAT3, MIF, CCL2, MMP9, and IL18. Forty obese subjects completed dietary intervention program, which resulted in 11.3% weight loss and 27% increase in insulin sensitivity (both p < 0.0001). AT IL6R, IL6ST, JAK1, and JAK2 expression increased, whereas MIF, CCL2, MMP9, and IL18 gene expression did not change in response to weight loss. BG addition had no effect on any of the parameters studied. CONCLUSIONS: Our data indicate that reduction in AT inflammation is not required for an improvement in insulin action during weight loss in subjects with uncomplicated obesity. BG does not have effects during dietary intervention.


Asunto(s)
Restricción Calórica , Expresión Génica , Inflamación/genética , Obesidad/dietoterapia , Grasa Subcutánea/metabolismo , Pérdida de Peso/fisiología , beta-Glucanos/administración & dosificación , Adulto , Femenino , Expresión Génica/efectos de los fármacos , Humanos , Inflamación/complicaciones , Inflamación/metabolismo , Inflamación/patología , Resistencia a la Insulina/genética , Masculino , Obesidad/complicaciones , Obesidad/genética , Obesidad/patología , Grasa Subcutánea/efectos de los fármacos , Grasa Subcutánea/patología , Adulto Joven , beta-Glucanos/farmacología
4.
Rocz Panstw Zakl Hig ; 63(1): 73-81, 2012.
Artículo en Polaco | MEDLINE | ID: mdl-22642073

RESUMEN

BACKGROUND: Changes in the structure and functioning of the body occur with age. Also nutrition is continually modified. Eating habits may affect favorably or unfavorably on the process of aging and the functioning of various tissues, organs and the whole body. OBJECTIVES: The purpose of the study was to evaluate dietary habits and food preferences of patients in different age groups. In the studied groups also body mass index (BMI) and body fat content were analyzed. MATERIAL AND METHOD: 237 people (133 women and 104 men, age 18-79 years) were examined. The participants completed questionnaires of the frequency of food consumption and food preferences. The height, weight, body mass index (BMI), the percentage of body fat (BIA) were also measured. For statistical analysis the assessment of correlation Spearman's rank order and nonparametric ANOVA rank Kruskal-Wallis were used. RESULTS: With age, the frequency of milk (p < 0,05) and cheese (p < 0,05) consumption decreased whereas consumption of cottage cheese increased (p < 0,05). Increased consumption of offal (p < 0,05), salt (p < 0,05) and coffee (p< 0, 05) was also noted. With age, the respondents preferred animal fats (p < 0.05) and vegetable fats (p < 0.05). The frequency of butter consumption decreased (p < 0.05) and consumption of vegetable fats increased (p < 0,05). The consumption of brown rice (p < 0,05), whole wheat pasta (p < 0,05) and cereals (p < 0,05) was reduced whereas the consumption of groats (p < 0,05) potatos (p < 0,05) and fruits (p < 0,05) increased. The decreased desire (p < 0,05) and frequency of nuts / almonds consumption (p < 0,05) were noted. With age, the BMI and percentage of body fat were increasing (p < 0,05, R = 0,39, p < 0,05, R = 0,31, respectively). CONCLUSIONS: Taste preferences and dietary habits vary depending on age and may be one of the elements affecting the increase in BMI, body fat content, bone mass loss and increased risk of metabolic disorders. The observed changes in dietary habits can contribute to the development of dyslipidemia, glucose dysmetabolism and arterial hypertension, especially in the presence of overweight and obesity.


Asunto(s)
Actitud Frente a la Salud , Dieta/estadística & datos numéricos , Conducta Alimentaria , Preferencias Alimentarias , Estado Nutricional , Adulto , Distribución por Edad , Factores de Edad , Anciano , Índice de Masa Corporal , Carbohidratos de la Dieta/administración & dosificación , Grasas de la Dieta/administración & dosificación , Fibras de la Dieta/administración & dosificación , Proteínas en la Dieta/administración & dosificación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores Socioeconómicos , Adulto Joven
5.
Monatsh Chem ; 142(11): 1121-1129, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-26166853

RESUMEN

ABSTRACT: In this work, the synthesis of various thiol-functionalized anthraquinone compounds is presented. The studied compounds were characterized by mass spectrometry and the main fragmentation pathways are discussed. The compounds studied formed stable self-assembled monolayers (SAMs) in the gold surface. The parameters for the reduction processes in the gold surface of the studied new anthraquinones were determined by cyclic voltamperometry tests.

6.
J Pept Sci ; 14(8): 911-6, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18351708

RESUMEN

With only 14 amino acid residues, the trypsin inhibitor SFTI-1 is the smallest naturally occurring serine proteinase inhibitor. It consists of two cyclic fragments (with head-to-tail cyclization and a disulfide bridge). In our previous paper, we showed that the removal of the disulfide bridge produced 2.4-fold lower activity. Here, we present the total conformational analysis of the [Abu(3, 11)]-SFTI-1 analog by means of 2D NMR spectroscopy in conjunction with theoretical methods. The peptide was synthesized by Fmoc SPPS. It was cyclized with PyBop and DIPEA in DMF. The NMR studies were performed in DMSO-d(6) at 303 K. Conformations of the peptide studied were calculated by the following three approaches: distance geometry (DG), molecular dynamics (MD) and determination of the statistical weights of conformations. The first two algorithms use a CHARMM force field, whereas the last uses an ECEPP/3 force field. Our calculations resulted in three sets of conformers with 7, 9 and 6 representatives, respectively. All our results were compared with published ones. It was found that the peptide has an ill-defined structure. Despite its conformational flexibility, the binding loop (3-11 fragment) displayed geometry similar to the corresponding fragments of the other SFTI-1 analogs and to the inhibitor itself. Furthermore, the peptide bond between the Ile7 and Pro8 residues adopts cis geometry, which is essential for inhibitory activity.


Asunto(s)
Aminobutiratos/química , Helianthus/química , Péptidos Cíclicos/química , Semillas/química , Inhibidores de Tripsina/química , Algoritmos , Simulación por Computador , Espectroscopía de Resonancia Magnética/métodos , Modelos Químicos , Modelos Moleculares , Peso Molecular , Péptidos Cíclicos/síntesis química , Péptidos Cíclicos/farmacología , Conformación Proteica , Tripsina/efectos de los fármacos , Inhibidores de Tripsina/síntesis química , Inhibidores de Tripsina/farmacología
7.
Photochem Photobiol ; 81(3): 697-704, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15691226

RESUMEN

Photophysical properties of tyrosine and its derivatives with free and blocked functional groups were studied by steady state and time-resolved fluorescence spectroscopy and global analysis in organic solvents, such as methanol, 2-propanol, tetrahydrofuran (THF), and dimethylsulfoxide (DMSO). The mono-exponential fluorescence intensity decays were observed for all tyrosine derivatives in THF and DMSO solutions, whereas in alcohols some derivatives have bi-exponential decays. The rotamer population calculated from 1H nuclear magnetic resonance spectroscopy in DMSO does not correspond to the pre-exponential factors obtained from fluorescence spectroscopy. Moreover in the case of DMSO, the strong interaction of this solvent with the hydroxyl group of the fluorophore's phenol ring causes substantial changes in the fluorescence and nonradiative rate constants of tyrosine derivatives compared with those of tyrosine with a blocked hydroxyl group, Tyr(Me). The steady state and time-resolved fluorescence measurements in pure organic solvents and water-organic solvent mixtures indicate that the fluorescence quenching of the phenol chromophore of tyrosine by an acetyl or amide group or both depends on the polarity of the solvent used as well as the ability of the solvent to form hydrogen bonds with functional groups of tyrosine.

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