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1.
Artigo em Inglês | MEDLINE | ID: mdl-31436047

RESUMO

BACKGROUND: A poor fat-soluble micronutrient (FMN) and a high oxidative stress status are associated with frailty. Our aim was to determine the cross-sectional association of FMNs and oxidative stress biomarkers [protein carbonyls (PrCarb) and 3-nitrotyrosine] with the frailty status in participants older than 65 years. METHODS: Plasma levels of vitamins A (retinol), D3 , E (α-tocopherol and γ-tocopherol) and carotenoids (α-carotene and ß-carotene, lycopene, lutein/zeaxanthin, and ß-cryptoxanthin), PrCarb, and 3-nitrotyrosine were measured in 1450 individuals of the FRAILOMIC initiative. Participants were classified into robust, pre-frail, and frail using Fried's frailty criteria. Associations between biomarkers and frailty status were assessed by general linear and logistic regression models, both adjusted for cohort, season of blood sampling, gender, age, height, weight, and smoking. RESULTS: Robust participants had significantly higher vitamin D3 and lutein/zeaxanthin concentrations than pre-frail and frail subjects; had significantly higher γ-tocopherol, α-carotene, ß-carotene, lycopene, and ß-cryptoxanthin concentrations than frail subjects, and had significantly lower PrCarb concentrations than frail participants in multivariate linear models. Frail subjects were more likely to be in the lowest than in the highest tertile for vitamin D3 (adjusted odds ratio: 2.15; 95% confidence interval: 1.42-3.26), α-tocopherol (2.12; 1.39-3.24), α-carotene (1.69; 1.00-2.88), ß-carotene (1.84; 1.13-2.99), lycopene (1.94; 1.24-3.05), lutein/zeaxanthin (3.60; 2.34-5.53), and ß-cryptoxanthin (3.02; 1.95-4.69) and were more likely to be in the highest than in the lowest tertile for PrCarb (2.86; 1.82-4.49) than robust subjects in multivariate regression models. CONCLUSIONS: Our study indicates that both low FMN and high PrCarb concentrations are associated with pre-frailty and frailty.

2.
Curr Opin Clin Nutr Metab Care ; 22(5): 355-362, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31145123

RESUMO

PURPOSE OF REVIEW: In addition to the currently available lysosomotropic drugs and autophagy whole-body knockout mouse models, we provide alternative methods that enable the modulation and detection of autophagic flux in vivo, discussing advantages and disadvantages of each method. RECENT FINDINGS: With the autophagosome-lysosome fusion inhibitor colchicine in skeletal muscle and temporal downregulation of autophagy using a novel Autophagy related 5-short hairpin RNA (Atg5-shRNA) mouse model we mention two models that directly modulate autophagy flux in vivo. Furthermore, methods to quantify autophagy flux, such as mitophagy transgenic reporters, in situ immunofluorescent staining and multispectral imaging flow cytometry, in mature skeletal muscle and cells are addressed. SUMMARY: To achieve clinical benefit, less toxic, temporary and cell-type-specific modulation of autophagy should be pursued further. A temporary knockdown as described for the Atg5-shRNA mice could provide a first insight into possible implications of autophagy inhibition. However, it is also important to take a closer look into the methods to evaluate autophagy after harvesting the tissue. In particular caution is required when experimental conditions can influence the final measurement and this should be pretested carefully.

3.
Redox Biol ; 24: 101204, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31022674

RESUMO

Recently, Weber et al. published a thorough investigation of the age-dependency of oxidative stress (OS) determined by the steady state concentrations of different compounds - oxidation products and antioxidants - that are in common use as biomarkers of OS in 2207 healthy individuals of the cross-sectional MARK-AGE Project. The correlations among biomarkers were significant but weak. These findings may indicate different manifestations of OS and must further be evaluated. Here, we report a refined analysis of OS based on the above-mentioned original data. We show that malondialdehyde (MDA) appears to be sensitive to both gender and age. It is significantly lower and shows a greater age-dependence in women than in men. The age-dependency of MDA in women arises in a stepwise fashion. The age-dependent slope of the steady state concentration is maximal at the age between 50 and 55 years, indicating that it may be attributed to the change of metabolism in the post-menopause. Interestingly, total glutathione (GSH) decreased with age simultaneously with the increase in MDA. Different biomarkers yield different gender- and age-dependencies. Unlike the concentration of MDA, the concentrations of the other two oxidation products, i.e. protein carbonyls and 3-nitrotyrosine were similar in men and women and appeared to be independent of age in the healthy study population. The analyzed antioxidants exhibited different gender- and age-dependencies. In conclusion, it appears that all the biomarkers assessed here reflect different types of OS and that MDA and GSH reflect the same type of OS.

4.
Cardiovasc Ultrasound ; 17(1): 7, 2019 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-31010431

RESUMO

Echocardiography is the most commonly applied technique for non-invasive assessment of cardiac function in small animals. Manual tracing of endocardial borders is time consuming and varies with operator experience. Therefore, we aimed to evaluate a novel automated two-dimensional software algorithm (Auto2DE) for small animals and compare it to the standard use of manual 2D-echocardiographic assessment (2DE). We hypothesized that novel Auto2DE will provide rapid and robust data sets, which are in agreement with manually assessed data of animals.2DE and Auto2DE were carried out using a high-resolution imaging-system for small animals. First, validation cohorts of mouse and rat cine loops were used to compare Auto2DE against 2DE. These data were stratified for image quality by a blinded expert in small animal imaging. Second, we evaluated 2DE and Auto2DE in four mouse models and four rat models with different cardiac pathologies.Automated assessment of LV function by 2DE was faster than conventional 2DE analysis and independent of operator experience levels. The accuracy of Auto2DE-assessed data in healthy mice was dependent on cine loop quality, with excellent agreement between Auto2DE and 2DE in cine loops with adequate quality. Auto2DE allowed for valid detection of impaired cardiac function in animal models with pronounced cardiac phenotypes, but yielded poor performance in diabetic animal models independent of image quality.Auto2DE represents a novel automated analysis tool for rapid assessment of LV function, which is suitable for data acquisition in studies with good and very good echocardiographic image quality, but presents systematic problems in specific pathologies.

5.
Nutrients ; 11(3)2019 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-30866427

RESUMO

For centuries, Amaranthus sp. were used as food, ornamentals, and medication. Molecular mechanisms, explaining the health beneficial properties of amaranth, are not yet understood, but have been attributed to secondary metabolites, such as phenolic compounds. One of the most abundant phenolic compounds in amaranth leaves is 2-caffeoylisocitric acid (C-IA) and regarding food occurrence, C-IA is exclusively found in various amaranth species. In the present study, the anti-inflammatory activity of C-IA, chlorogenic acid, and caffeic acid in LPS-challenged macrophages (RAW 264.7) has been investigated and cellular contents of the caffeic acid derivatives (CADs) were quantified in the cells and media. The CADs were quantified in the cell lysates in nanomolar concentrations, indicating a cellular uptake. Treatment of LPS-challenged RAW 264.7 cells with 10 µM of CADs counteracted the LPS effects and led to significantly lower mRNA and protein levels of inducible nitric oxide synthase, tumor necrosis factor alpha, and interleukin 6, by directly decreasing the translocation of the nuclear factor κB/Rel-like containing protein 65 into the nucleus. This work provides new insights into the molecular mechanisms that attribute to amaranth's anti-inflammatory properties and highlights C-IA's potential as a health-beneficial compound for future research.


Assuntos
Amaranthus/química , Anti-Inflamatórios/farmacologia , Ácidos Cafeicos/farmacologia , Isocitratos/farmacologia , NF-kappa B/metabolismo , Animais , Ácidos Cafeicos/química , Citocinas/metabolismo , Isocitratos/química , Lipopolissacarídeos/efeitos adversos , Camundongos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Células RAW 264.7 , Transdução de Sinais/efeitos dos fármacos
6.
Nutr Diabetes ; 9(1): 9, 2019 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-30858378

RESUMO

Diet-induced hyperglycemia is described as one major contributor to the formation of advanced glycation end products (AGEs) under inflammatory conditions, crucial in type 2 diabetes progression. Previous studies have indicated high postprandial plasma AGE-levels in diabetic patients and after long-term carbohydrate feeding in animal models. Pancreatic islets play a key role in glucose metabolism; thus, their susceptibility to glycation reactions due to high amounts of dietary carbohydrates is of special interest. Therefore, diabetes-prone New Zealand Obese (NZO) mice received either a carbohydrate-free, high-fat diet (CFD) for 11 weeks or were additionally fed with a carbohydrate-rich diet (CRD) for 7 days. In the CRD group, hyperglycemia and hyperinsulinemia were induced accompanied by increasing plasma 3-nitrotyrosine (3-NT) levels, higher amounts of 3-NT and inducible nitric oxide synthase (iNOS) within pancreatic islets. Furthermore, N-ε-carboxymethyllysine (CML) was increased in the plasma of CRD-fed NZO mice and substantially higher amounts of arg-pyrimidine, pentosidine and the receptor for advanced glycation end products (RAGE) were observed in pancreatic islets. These findings indicate that a short-term intervention with carbohydrates is sufficient to form endogenous AGEs in plasma and pancreatic islets of NZO mice under hyperglycemic and inflammatory conditions.

7.
FASEB J ; 33(6): 7092-7102, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30841758

RESUMO

Dietary methionine restriction (MR) is well known to reduce body weight by increasing energy expenditure (EE) and insulin sensitivity. An elevated concentration of circulating fibroblast growth factor 21 (FGF21) has been implicated as a potential underlying mechanism. The aims of our study were to test whether dietary MR in the context of a high-fat regimen protects against type 2 diabetes in mice and to investigate whether vegan and vegetarian diets, which have naturally low methionine levels, modulate circulating FGF21 in humans. New Zealand obese (NZO) mice, a model for polygenic obesity and type 2 diabetes, were placed on isocaloric high-fat diets (protein, 16 kcal%; carbohydrate, 52 kcal%; fat, 32 kcal%) that provided methionine at control (Con; 0.86% methionine) or low levels (0.17%) for 9 wk. Markers of glucose homeostasis and insulin sensitivity were analyzed. Among humans, low methionine intake and circulating FGF21 levels were investigated by comparing a vegan and a vegetarian diet to an omnivore diet and evaluating the effect of a short-term vegetarian diet on FGF21 induction. In comparison with the Con group, MR led to elevated plasma FGF21 levels and prevented the onset of hyperglycemia in NZO mice. MR-fed mice exhibited increased insulin sensitivity, higher plasma adiponectin levels, increased EE, and up-regulated expression of thermogenic genes in subcutaneous white adipose tissue. Food intake and fat mass did not change. Plasma FGF21 levels were markedly higher in vegan humans compared with omnivores, and circulating FGF21 levels increased significantly in omnivores after 4 d on a vegetarian diet. These data suggest that MR induces FGF21 and protects NZO mice from high-fat diet-induced glucose intolerance and type 2 diabetes. The normoglycemic phenotype in vegans and vegetarians may be caused by induced FGF21. MR akin to vegan and vegetarian diets in humans may offer metabolic benefits via increased circulating levels of FGF21 and merits further investigation.-Castaño-Martinez, T., Schumacher, F., Schumacher, S., Kochlik, B., Weber, D., Grune, T., Biemann, R., McCann, A., Abraham, K., Weikert, C., Kleuser, B., Schürmann, A., Laeger, T. Methionine restriction prevents onset of type 2 diabetes in NZO mice.

8.
Graefes Arch Clin Exp Ophthalmol ; 257(5): 931-952, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30693383

RESUMO

PURPOSE: To examine the reaction of microglial cells (MG) when incubated with lipofuscin (LP) in vitro with emphasis on the immunological reaction of the MG toward LP and the suppression of this reaction by immunomodulatory agents. MG are involved in the pathogenesis of degenerative eye disorders such as age-related macular degeneration (AMD). LP is a heterogeneous waste material that accumulates in the retinal pigment epithelium (RPE) cells with advancing age. LP is known to have toxic effects on RPE cells and therefore an elevated LP-derived fundus autofluorescence is a risk factor for AMD development. MG in the subretinal space have been reported in eyes affected by AMD. Moreover, in senescent mice, subretinal MG were found, which display an autofluorescence that may be derived from LP uptake. METHODS: In this study, we incubated MG (BV-2 cell line and primary cells from murine brain) in vitro with LP isolated from the human RPE. We observed phagocytosis, studied cell morphologies, and analyzed the cell culture supernatants. We also investigated the effect of the immunomodulatory agents hydrocortisone (HC), minocycline, and the tripeptide TKP. RESULTS: The MG phagocytosed the LP quickly and completely. We detected highly elevated levels of pro-inflammatory cytokines (especially of IL-6, IL-23p19, TNF-α, KC, RANTES, and IL-1α) in the cell culture supernatants. Furthermore, levels of vascular endothelial growth factor (VEGF) were raised in BV-2 cells. Anti-inflammatory agents added to the cell cultures inhibited the inflammatory reaction, in particular hydrocortisone (HC). Minocycline and TKP had less impact on the cytokine release. CONCLUSION: The interaction of MG and LP could play a role in the development of retinal degeneration by triggering an inflammatory reaction and angiogenesis.


Assuntos
Lipofuscina/farmacologia , Degeneração Macular/diagnóstico , Microglia/ultraestrutura , Epitélio Pigmentado da Retina/ultraestrutura , Idoso , Animais , Células Cultivadas , Citocinas/metabolismo , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Humanos , Degeneração Macular/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Microglia/efeitos dos fármacos , Microscopia Eletrônica , Epitélio Pigmentado da Retina/efeitos dos fármacos
9.
Redox Biol ; 21: 101108, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30660959

RESUMO

Aging is accompanied by the accumulation of oxidized proteins. To remove them, cells employ the proteasomal and autophagy-lysosomal systems; however, if the clearance rate is inferior to its formation, protein aggregates form as a hallmark of proteostasis loss. In cells, during stress conditions, actin aggregates accumulate leading to impaired proliferation and reduced proteasomal activity, as observed in cellular senescence. The heat shock protein 90 (Hsp90) is a molecular chaperone that binds and protects the proteasome from oxidative inactivation. We hypothesized that in oxidative stress conditions a malfunction of Hsp90 occurs resulting in the aforementioned protein aggregates. Here, we demonstrate that upon oxidative stress Hsp90 loses its function in a highly specific non-enzymatic iron-catalyzed oxidation event and its breakdown product, a cleaved form of Hsp90 (Hsp90cl), acquires a new function in mediating the accumulation of actin aggregates. Moreover, the prevention of Hsp90 cleavage reduces oxidized actin accumulation, whereas transfection of the cleaved form of Hsp90 leads to an enhanced accumulation of oxidized actin. This indicates a clear role of the Hsp90cl in the aggregation of oxidized proteins.


Assuntos
Actinas/metabolismo , Proteínas de Choque Térmico HSP90/metabolismo , Estresse Oxidativo , Actinas/genética , Linhagem Celular , Mutação com Ganho de Função , Proteínas de Choque Térmico HSP90/genética , Humanos , Ferro/metabolismo , Modelos Biológicos , Estresse Oxidativo/genética , Complexo de Endopeptidases do Proteassoma/metabolismo , Agregados Proteicos , Agregação Patológica de Proteínas , Proteólise
10.
Am J Clin Nutr ; 108(6): 1209-1219, 2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30541098

RESUMO

Background: A diet in which fat is mainly eaten in the morning and carbohydrates mainly in the evening (compared with the reverse order) was recently shown to worsen glycemic control in people with prediabetes. Objective: We investigated the effects of these dietary patterns on energy metabolism, and on the daily profiles of circulating lipids, adipokines, and inflammatory markers. Design: In a randomized controlled crossover trial, 29 nonobese men (with normal glucose tolerance, n = 18; or impaired fasting glucose/glucose tolerance, n = 11) underwent 2 isocaloric 4-wk diets: 1) carbohydrate-rich meals until 1330 and fat-rich meals between 1630 and 2200 (HC/HF); or 2) the inverse sequence of meals (HF/HC). During a 12-h clinical investigation day after each intervention period, 2 meal tolerance tests were performed, at 0900 and 1540, respectively. Substrate oxidation and concentrations of circulating lipids, adipokines, and cytokines were assessed pre- and postprandially. The postprandial inflammatory response in leukocytes was analyzed ex vivo. Results: Fasting carbohydrate oxidation decreased (P = 0.004) and lipid oxidation increased (P = 0.012) after the HC/HF diet. Fasting concentrations of blood markers did not differ between diets. The diets modulated the daily profiles of carbohydrate oxidation, lipid oxidation, and ß-hydroxybutyrate, although the average daily values of these parameters showed no difference between the diets, and no interaction between diet and glucose tolerance status. Diurnal patterns of triglycerides, low-density lipoprotein cholesterol, leptin, visfatin, and of LPS-induced cytokine secretion in blood leukocytes were also modulated by the diets. Average daily concentrations of leptin (P = 0.017) and visfatin (P = 0.041) were lower on the HF/HC diet than on the HC/HF diet. Conclusions: Diurnal distribution of carbohydrates and fat affects the daily profiles of substrate oxidation, circulating lipids, and cytokine secretion, and alters the average daily concentrations of adipokine secretion in nonobese nondiabetic humans. The study was registered at clinicaltrials.gov as NCT02487576.


Assuntos
Adipocinas/metabolismo , Ritmo Circadiano/fisiologia , Carboidratos da Dieta/administração & dosagem , Gorduras na Dieta/administração & dosagem , Metabolismo Energético/efeitos dos fármacos , Adulto , Biomarcadores/sangue , Índice de Massa Corporal , Estudos Cross-Over , Citocinas/sangue , Carboidratos da Dieta/metabolismo , Gorduras na Dieta/metabolismo , Jejum , Intolerância à Glucose/metabolismo , Humanos , Inflamação/sangue , Leptina/sangue , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Nicotinamida Fosforribosiltransferase/sangue , Oxirredução , Período Pós-Prandial
11.
Sci Rep ; 8(1): 16318, 2018 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-30397214

RESUMO

The proteasomal system is responsible for the turnover of damaged proteins. Because of its important functions in oncogenesis, inhibiting the proteasomal system is a promising therapeutic approach for cancer treatment. Bortezomib (BTZ) is the first proteasome inhibitor approved by FDA for clinical applications. However neuropathic side effects are dose limiting for BTZ as many other chemotherapeutic agents. Therefore second-generation proteasome inhibitors have been developed including carfilzomib (CFZ). Aim of the present work was investigating the mechanisms of peripheral neuropathy triggered by the proteasome inhibitor BTZ and comparing the pathways affected by BTZ and CFZ, respectively. Neural stem cells, isolated from the cortex of E14 mouse embryos, were treated with BTZ and CFZ and mass spectrometry was used to compare the global protein pool of treated cells. BTZ was shown to cause more severe cytoskeletal damage, which is crucial in neural cell integrity. Excessive protein carbonylation and actin filament destabilization were also detected following BTZ treatment that was lower following CFZ treatment. Our data on cytoskeletal proteins, chaperone system, and protein oxidation may explain the milder neurotoxic effects of CFZ in clinical applications.

12.
AIDS ; 2018 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-30325781

RESUMO

OBJECTIVES: Despite successful antiretroviral (ARV) therapy, people living with HIV (PLWH) may show signs of premature/accentuated aging. We compared established biomarkers of aging in PLWH, appropriately-chosen HIV-negative individuals, and blood donors, and explored factors associated with biological age advancement. DESIGN: Cross-sectional analysis of 134 PLWH on suppressive ARV therapy, 79 lifestyle-comparable HIV-negative controls aged ≥45 years from the Co-morBidity in Relation to AIDS (COBRA) cohort, and 35 age-matched blood donors (BD). METHODS: Biological age was estimated using a validated algorithm based on ten biomarkers. Associations between 'age advancement' (biological minus chronological age) and HIV status/parameters, lifestyle, cytomegalovirus (CMV), hepatitis B (HBV) and hepatitis C virus (HCV) infections were investigated using linear regression. RESULTS: The average (95% CI) age advancement was greater in both HIV-positive [13.2 (11.6, 14.9) years] and HIV-negative [5.5 (3.8, 7.2) years] COBRA participants compared to BD [-7.0 (-4.1, -9.9) years, both p's < 0.001)], but also in HIV-positive compared to HIV-negative participants (p < 0.001). Chronic HBV, higher anti-CMV IgG titer and CD8 T-cell count were each associated with increased age advancement, independently of HIV-status/group. Among HIV-positive participants, age advancement was increased by 3.5 (0.1, 6.8) years among those with nadir CD4 < 200 cells/µL and by 0.1 (0.06, 0.2) years for each additional month of exposure to saquinavir. CONCLUSIONS: Both treated PLWH and lifestyle-comparable HIV-negative individuals show signs of age advancement compared to BD, to which persistent CMV, HBV co-infection and CD8 T-cell activation may have contributed. Age advancement remained greatest in PLWH and was related to prior immunodeficiency and cumulative saquinavir exposure.This is an open access article distributed under the terms of the Creative Commons Attribution-Non Commercial-No Derivatives License 4.0 (CCBY-NC-ND), where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially without permission from the journal. http://creativecommons.org/licenses/by-nc-nd/4.0.

13.
Exp Gerontol ; 2018 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-30367978

RESUMO

The skeletal muscle is a crucial tissue for maintaining whole body homeostasis. Aging seems to have a disruptive effect on skeletal muscle homeostasis including proteostasis. However, how aging specifically impacts slow and fast twitch fiber types remains elusive. Muscle proteostasis is largely maintained by the proteasomal system. Here we characterized the proteasomal system in two different fiber types, using a non-sarcopenic aging model. By analyzing the proteasomal activity and amount, as well as the polyubiquitinated proteins and the level of protein oxidation in Musculus soleus (Sol) and Musculus extensor digitorum longus (EDL), we found that the slow twitch Sol muscle shows an overall higher respiratory and proteasomal activity in young and old animals. However, especially during aging the fast twitch EDL muscle reduces protein oxidation by an increase of antioxidant capacity. Thus, under adaptive non-sarcopenic conditions, the two fibers types seem to have different strategies to avoid age-related changes.

14.
Free Radic Biol Med ; 2018 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-30194981

RESUMO

Aging is a complex phenomenon that has detrimental effects on tissue homeostasis. The skeletal muscle is one of the earliest tissues to be affected and to manifest age-related changes such as functional impairment and the loss of mass. Common to these alterations and to most of tissues during aging is the disruption of the proteostasis network by detrimental changes in the ubiquitin-proteasomal system (UPS) and the autophagy-lysosomal system (ALS). In fact, during aging the accumulation of protein aggregates, a process mainly driven by increased levels of oxidative stress, has been observed, clearly demonstrating UPS and ALS dysregulation. Since the UPS and ALS are the two most important pathways for the removal of misfolded and aggregated proteins and also of damaged organelles, we provide here an overview on the current knowledge regarding the connection between the loss of proteostasis and skeletal muscle functional impairment and also how redox regulation can play a role during aging. Therefore, this review serves for a better understanding of skeletal muscle aging in regard to the loss of proteostasis and how redox regulation can impact its function and maintenance.

16.
Ageing Res Rev ; 47: 55-66, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29969676

RESUMO

Due to their bioactivity and harmful potential, advanced glycation end products (AGEs) are discussed to affect human health. AGEs are compounds formed endogenously in the human body andexogenously, especially, in foods while thermal processing. In contrast to endogenous AGEs, dietary AGEs are formed in much higher extent. However, their risk potential is also depending on absorption, distribution, metabolism and elimination. For over 10 years an intense debate on the risk of dietary AGEs on human health is going on. On the one hand, studies provided evidence that dietary AGEs contribute to clinical outcomes. On the other hand, human studies failed to observe any association. Because it was not possible to draw a final conclusion, the call for new interdisciplinary approaches arose. In this review, we will give an overview on the current state of scientific knowledge in this field. In particular, we focus on (I) the occurrence of AGEs in foods and the daily uptake of AGEs, (II) contribution to endogenous levels and (III) the effect on health-/disease-related biomarkers in humans.

17.
Cardiovasc Ultrasound ; 16(1): 10, 2018 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-29966517

RESUMO

BACKGROUND: The assessment of ventricular volumes using conventional echocardiography methods is limited with regards to the need of geometrical assumptions. In the present study, we aimed to evaluate a novel commercial system for three-dimensional echocardiography (3DE) in preclinical models by direct comparison with conventional 1D- and 2D-echocardiography (1DE; 2DE) and the gold-standard technique magnetic resonance imaging (MRI). Further, we provide a standard operating protocol for image acquisition and analysis with 3DE. METHODS: 3DE was carried out using a 30 MHz center frequency transducer coupled to a Vevo®3100 Imaging System. We evaluated under different experimental conditions: 1) in vitro phantom measurements served as controlled setting in which boundaries were clearly delineated; 2) a validation cohort composed of healthy C57BL/6 J mice and New Zealand Obese (NZO) mice was used in order to validate 3DE against cardiac MRI; 3) a standard mouse model of pressure overload induced-heart failure was investigated to estimate the value of 3DE. RESULTS: First, in vitro volumetry revealed good agreement between 3DE assessed volumes and the MRI-assessed volumes. Second, cardiac volume determination with 3DE showed smaller mean differences compared to cardiac MRI than conventional 1DE and 2DE. Third, 3DE was suitable to detect reduced ejection fractions in heart failure mice. Fourth, inter- and intra-observer variability of 3DE showed good to excellent agreement regarding absolute volumes in healthy mice, whereas agreement rates for the relative metrics ejection fraction and stroke volume demonstrated good to moderate observer variabilities. CONCLUSIONS: 3DE provides a novel method for accurate volumetry in small animals without the need for spatial assumptions, demonstrating a technique for an improved analysis of ventricular function. Further validation work and highly standardized image analyses are required to increase reproducibility of this approach.


Assuntos
Ecocardiografia Tridimensional , Insuficiência Cardíaca/diagnóstico por imagem , Volume Sistólico , Animais , Modelos Animais de Doenças , Ecocardiografia , Interpretação de Imagem Assistida por Computador , Processamento de Imagem Assistida por Computador , Imagem por Ressonância Magnética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Obesos , Variações Dependentes do Observador , Reprodutibilidade dos Testes
18.
Sci Rep ; 8(1): 11382, 2018 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-30038285

RESUMO

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.

19.
Mech Ageing Dev ; 2018 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-29719199

RESUMO

Frailty among elderly people leads to an increased risk for negative health outcomes. To prevent frailty, we need a better understanding of the underlying mechanisms and early detection of individuals at risk. Both may be served by identifying candidate (bio)markers, i.e. biomarkers and markers, for the physical, cognitive, and psychological frailty domains. We used univariate (Rank-ANOVA) and multivariate (elastic net) approaches on the RASIG study population (age range: 35-74 years, n = 2220) of the MARK-AGE study to study up to 331 (bio)markers between individuals with and without frailty for each domain. Biomarkers and markers identified by both approaches were studied further regarding their association with frailty using logistic regression. Univariately, we found lower levels of antioxidants, including ß-cryptoxanthin and zeaxanthin, in those who were physically, cognitively or psychologically frail. Additionally, self-reported health was worse in these three frail groups. Multivariately, we observed lower levels of ß-cryptoxanthin and zeaxanthin in the cognitively frail. Levels of these carotenoids were inversely associated with the risk of being cognitively frail after adjusting for confounders. Antioxidants and self-reported health are potential (bio)markers to detect persons at risk of becoming frail. The biomarkers identified may indicate the involvement of inflammation in frailty, especially for physical and cognitive frailty.

20.
Redox Biol ; 17: 236-245, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29727801

RESUMO

A new fluorometric assay is presented for the ultrasensitive quantification of total protein carbonyls, and is based on their specific reaction with rhodamine B hydrazide (RBH), and the production of a protein carbonyl-RBH hydrazone the fluorescence of which (at ex/em 560/585 nm) is greatly enhanced by guanidine-HCl. Compared to the fluorescein-5-thiosemicarbazide (FTC)-based fluorometric assay, the RBH assay uses a 24-fold shorter reaction incubation time (1 h) and at least 1000-fold lower protein quantity (2.5 µg), and produces very reliable data that were verified by extensive standardization experiments. The protein carbonyl group detection sensitivity limit of the RBH assay, based on its standard curve, can be as low as 0.4 pmol, and even lower. Counting the very low protein limit of the RBH assay, its cumulative and functional sensitivity is 8500- and 800-fold higher than the corresponding ones for the FTC assay. Neither heme proteins hemoglobin and cytochrome c nor DNA interfere with the RBH assay.


Assuntos
Fluorometria/métodos , Hidrazinas/química , Carbonilação Proteica , Rodaminas/química , Fluoresceínas/química , Corantes Fluorescentes/química , Guanidina/química , Hemoglobinas
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