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1.
Artigo em Inglês | MEDLINE | ID: mdl-39402854

RESUMO

Background: This study investigated the prognostic importance of the hemoglobin glycation index (HGI) for macrovascular and microvascular outcomes, mortality, and hypoglycemia occurrence in a type 2 diabetes cohort and compared it to glycated hemoglobin (HbA1c). Methods: Baseline and mean first-year HGI and HbA1c, and the variability thereof, were assessed in 687 individuals with type 2 diabetes (median follow-up, 10.6 years). Multivariable Cox regression was conducted to evaluate the associations of HGI and HbA1c parameters with macrovascular (total and major cardiovascular events) and microvascular outcomes (microalbuminuria, advanced renal failure, retinopathy, and peripheral neuropathy), mortality (all-cause and cardiovascular), and moderate/severe hypoglycemia occurrence. Results: During follow-up, there were 215 total cardiovascular events (176 major) and 269 all-cause deaths (131 cardiovascular). Microalbuminuria developed in 126 patients, renal failure in 104, retinopathy in 161, and neuropathy in 177. There were 90 hypoglycemia episodes. Both HGI and HbA1c predicted all adverse outcomes, except microalbuminuria and hypoglycemia. Their adjusted risks were roughly equivalent for all outcomes. For example, the adjusted hazard ratios (HRs) with 95% confidence intervals (CIs), estimated for 1 standard deviation increments, of mean first-year HGI were 1.23 (1.05 to 1.44), 1.20 (1.03 to 1.38), 1.36 (1.11 to 1.67), 1.28 (1.09 to 1.67), and 1.29 (1.09 to 1.54), respectively, for cardiovascular events, all-cause mortality, renal failure, retinopathy, and neuropathy; whereas the respective HRs (95% CIs) of mean HbA1c were 1.31 (1.12 to 1.53), 1.28 (1.11 to 1.48), 1.36 (1.11 to 1.67), 1.33 (1.14 to 1.55), and 1.29 (1.09 to 1.53). Conclusion: HGI was no better than HbA1c as a predictor of adverse outcomes in individuals with type 2 diabetes, and its clinical use cannot be currently advised.

2.
Pharmaceuticals (Basel) ; 17(9)2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39338363

RESUMO

Bixin (C25H30O4; 394.51 g/mol) is the main apocarotenoid found in annatto seeds. It has a 25-carbon open chain structure with a methyl ester group and carboxylic acid. Bixin increases the expression of antioxidant enzymes, which may be interesting for counteracting oxidative stress. This study investigated whether bixin-rich annatto extract combined with metformin was able to improve the disturbances observed in high-fat diet (HFD)-induced obesity in mice, with an emphasis on markers of oxidative damage and antioxidant defenses. HFD-fed mice were treated for 8 weeks with metformin (50 mg/kg) plus bixin-rich annatto extract (5.5 and 11 mg/kg). This study assessed glucose tolerance, insulin sensitivity, lipid profile and paraoxonase 1 (PON-1) activity in plasma, fluorescent AGEs (advanced glycation end products), TBARSs (thiobarbituric acid-reactive substances), and the activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) in the liver and kidneys. Treatment with bixin plus metformin decreased body weight gain, improved insulin sensitivity, and decreased AGEs and TBARSs in the plasma, liver, and kidneys. Bixin plus metformin increased the activities of PON-1, SOD, CAT, and GSH-Px. Bixin combined with metformin improved the endogenous antioxidant defenses in the obese mice, showing that this combined therapy may have the potential to contrast the metabolic complications resulting from oxidative stress.

3.
Food Chem ; 463(Pt 1): 141085, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39243619

RESUMO

The influence of oxygen on the thermal treatment (TT) of secondary metabolite-enriched extracts (SMEEs) from Tórtola beans and procyanidin C1 (PC1) on the inhibition of advanced glycation end products (AGEs) generation in proteins was investigated. SMEE was incubated at 4 °C (control) or thermally treated at 60 °C for 2 h, at either 0 % O2 (I) or 20 % O2 (II). Treatments I and II increased the content of procyanidin dimers B2. Treatment II was more effective than the control or treatment I in preventing homocysteine oxidation and AGEs generation. TT of PC1 at 0 % or 20 % O2 generated procyanidin dimers and tetramers. PC1 TT at 20 % O2 exhibited higher oxidation potentials and lower IC50 values of fluorescent AGEs than those of controls or TT at 0 % O2. These findings indicate that SMEE from Tórtola beans after treatment II changes the degree of polymerization and oxidation procyanidins, thereby increasing their antiglycation activity.

4.
Int J Mol Sci ; 25(15)2024 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-39125811

RESUMO

Advanced glycated end products (AGEs) are cytotoxic compounds that are mainly increased in diabetes mellitus (DM), kidney failure, inflammation, and in response to the ingestion of AGE-rich diets. AGEs can also impair glycemic homeostasis by decreasing the expression of the Slc2a4 (solute carrier family 2 member 4) gene and its GLUT4 (solute carrier family 2, facilitated glucose transporter member 4) protein in muscle. However, the mechanisms underlying AGE's effect on adipocytes have not been demonstrated yet. This study investigated the effects of AGEs upon Slc2a4/GLUT4 expression in 3T3-L1 adipocytes, as well as the potential role of NFKB (nuclear factor NF-kappa-B) activity in the effects observed. Adipocytes were cultured in the presence of control albumin (CA) or advanced glycated albumin (GA) at concentrations of 0.4, 3.6, and 5.4 mg/mL for 24 h or 72 h. Slc2a4, Rela, and Nfkb1mRNAs were measured by RT-qPCR, GLUT4, IKKA/B, and p50/p65 NFKB subunits using Western blotting, and p50/p65 binding into the Slc2a4 promoter was analyzed by chromatin immunoprecipitation (ChIP) assay. GA at 0.4 mg/mL increased Slc2a4/GLUT4 expression after 24 h and 72 h (from 50% to 100%), but at 5.4 mg/mL, Slc2a4/GLUT4 expression decreased at 72 h (by 50%). Rela and Nfkb1 expression increased after 24 h at all concentrations, but this effect was not observed at 72 h. Furthermore, 5.4 mg/mL of GA increased the p50/p65 nuclear content and binding into Slc2a4 at 72 h. In summary, this study reveals AGE-induced and NFKB-mediated repression of Slc2a4/GLUT4 expression. This can compromise the adipocyte glucose utilization, contributing not only to the worsening of glycemic control in DM subjects but also the impairment of glycemic homeostasis in non-DM subjects under the high intake of AGE-rich foods.


Assuntos
Células 3T3-L1 , Adipócitos , Transportador de Glucose Tipo 4 , Produtos Finais de Glicação Avançada , Fator de Transcrição RelA , Animais , Camundongos , Adipócitos/metabolismo , Adipócitos/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Transportador de Glucose Tipo 4/metabolismo , Transportador de Glucose Tipo 4/genética , Produtos Finais de Glicação Avançada/metabolismo , Produtos Finais de Glicação Avançada/farmacologia , NF-kappa B/metabolismo , Subunidade p50 de NF-kappa B/metabolismo , Subunidade p50 de NF-kappa B/genética , Regiões Promotoras Genéticas , Fator de Transcrição RelA/metabolismo , Fator de Transcrição RelA/genética
5.
Vitam Horm ; 125: 183-229, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38997164

RESUMO

Hemoglobin (Hb) is a hemeprotein found inside erythrocytes and is crucial in transporting oxygen and carbon dioxide in our bodies. In erythrocytes (Ery), the main energy source is glucose metabolized through glycolysis. However, a fraction of Hb can undergo glycation, in which a free amine group from the protein spontaneously binds to the carbonyl of glucose in the bloodstream, resulting in the formation of glycated hemoglobin (HbA1c), widely used as a marker for diabetes. Glycation leads to structural and conformational changes, compromising the function of proteins, and is intensified in the event of hyperglycemia. The main changes in Hb include structural alterations to the heme group, compromising its main function (oxygen transport). In addition, amyloid aggregates can form, which are strongly related to diabetic complications and neurodegenerative diseases. Therefore, this chapter discusses in vitro protocols for producing glycated Hb, as well as the main techniques and biophysical assays used to assess changes in the protein's structure before and after the glycation process. This more complete understanding of the effects of glycation on Hb is fundamental for understanding the complications associated with hyperglycemia and for developing more effective prevention and treatment strategies.


Assuntos
Hemoglobinas , Humanos , Glicosilação , Hemoglobinas/metabolismo , Hemoglobinas/química , Hemoglobinas Glicadas/metabolismo , Conformação Proteica , Animais
6.
Nutr Rev ; 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38719207

RESUMO

CONTEXT: Consumption of the Mediterranean diet (MedDiet) has beneficial effects on cardiometabolic health and aging. OBJECTIVE: This systematic review aimed to critically investigate the effect of the MedDiet on glycation markers in healthy or overweight individuals with type 2 diabetes or cardiovascular disease. DATA SOURCES: MEDLINE, EMBASE, Web of Science, and the Cochrane Library were searched, using the terms "Mediterranean diet" AND "glycation end products, advanced". DATA EXTRACTION: Three randomized and 3 nonrandomized clinical trials, containing data on 2935 adult and elderly individuals with normal weight or overweight, were included. All extracted data were compiled, compared, and critically analyzed. DATA ANALYSIS: The authors of most of the studies demonstrated a reduction in serum concentrations of advanced glycation end products (AGEs), such as εN-carboxymethyllysine and methylglyoxal, and in skin autofluorescence levels after at least 4 weeks of adherence to the MedDiet. The MedDiet also led to positive effects on gene expression of receptors for AGEs, as RAGE and AGER1, and an enzyme involved in detoxification (glyoxalase I). There is no evidence that short-term adherence affects glycation markers. CONCLUSIONS: Glycation markers improved in response to the MedDiet. The possible mechanisms involved may be related to the low AGE and refined sugars content of the diet, as well as its high monounsaturated fatty acid, phenolic compound, and dietary fiber contents. SYSTEMATIC REVIEW REGISTRATION: PROSPERO registration no. CRD42021284006.

7.
Heliyon ; 10(7): e28675, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38571598

RESUMO

The receptor for advanced glycation end products (RAGE) and its gene (AGER) have been related to lung injury and inflammatory diseases, including chronic obstructive pulmonary disease (COPD). We aimed to evaluate the association of rs2071288, rs3134940, rs184003, and rs2070600 AGER single-nucleotide variants and the soluble-RAGE plasma and sputum levels with COPD secondary to biomass-burning smoke (BBS) and tobacco smoking. Four groups, including 2189 subjects, were analyzed: COPD secondary to BBS exposure (COPD-BBS, n = 342), BBS-exposed subjects without COPD (BBES, n = 774), tobacco smoking-induced COPD (COPD-TS, n = 434), and smokers without COPD (SWOC, n = 639). Allelic discrimination assays determined the AGER variants. The sRAGE was quantified in plasma (n = 240) and induced-sputum (n = 72) samples from a subgroup of patients using the ELISA technique. In addition, a meta-analysis was performed for the association of rs2070600 with COPD susceptibility. None of the studied genetic variants were found to be associated with COPD-BBS or COPD-TS. A marginal association was observed for the rs3134940 with COPD-BBS (p = 0.066). The results from the meta-analysis, including six case-control studies (n = 4149 subjects), showed a lack of association of rs2070600 with COPD susceptibility (p = 0.681), probably due to interethnic differences. The sRAGE plasma levels were lower in COPD-BBS compared to BBS and in COPD-TS compared to SWOC. The sRAGE levels were also lower in sputum samples from COPD-BBS than BBES. Subjects with rs3134940-TC genotypes exhibit lower sRAGE plasma levels than TT subjects, mainly from the COPD-BBS and SWOC groups. The AGER variants were not associated with COPD-BBS nor COPD-TS, but the sRAGE plasma and sputum levels are related to both COPD-BBS and COPD-TS and are influenced by the rs3134940 variant.

8.
Endocr Regul ; 58(1): 57-67, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38563294

RESUMO

Advanced glycation end products (AGEs) are a diverse group of compounds that are formed as a result of the non-enzymatic reaction between a reducing sugar such as glucose and the free NH2 groups of an amino acid in a protein or other biomolecule. The chemical reaction, by which these products are generated, is known as the Maillard reaction and occurs as a part of the body's normal metabolism. Such a reaction is enhanced during diabetes due to hyperglycemia, but it can also occur during the preparation, processing, and preservation of certain foods. Therefore, AGEs can also be obtained from the diet (d-AGE) and contribute to an increase of the total serum pool of these compounds. They have been implicated in a wide variety of pathological processes, mainly because of their ability to induce inflammatory responses and oxidative stress increase. They are extensively accumulated as a part of the normal aging, especially in tissues rich in long half-life proteins, which can compromise the physiology of these tissues. d-AGEs are abundant in diets rich in processed fats and sugars. This review is addressed to the current knowledge on these products and their impact on the immunomodulation of various mechanisms that may contribute to exacerbation of the diabetes pathophysiology.


Assuntos
Diabetes Mellitus , Produtos Finais de Glicação Avançada , Humanos , Produtos Finais de Glicação Avançada/metabolismo , Dieta/efeitos adversos , Reação de Maillard , Inflamação
9.
Biomolecules ; 14(4)2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38672429

RESUMO

In 1992, a transcendental report suggested that the receptor of advanced glycation end-products (RAGE) functions as a cell surface receptor for a wide and diverse group of compounds, commonly referred to as advanced glycation end-products (AGEs), resulting from the non-enzymatic glycation of lipids and proteins in response to hyperglycemia. The interaction of these compounds with RAGE represents an essential element in triggering the cellular response to proteins or lipids that become glycated. Although initially demonstrated for diabetes complications, a growing body of evidence clearly supports RAGE's role in human diseases. Moreover, the recognizing capacities of this receptor have been extended to a plethora of structurally diverse ligands. As a result, it has been acknowledged as a pattern recognition receptor (PRR) and functionally categorized as the RAGE axis. The ligation to RAGE leads the initiation of a complex signaling cascade and thus triggering crucial cellular events in the pathophysiology of many human diseases. In the present review, we intend to summarize basic features of the RAGE axis biology as well as its contribution to some relevant human diseases such as metabolic diseases, neurodegenerative, cardiovascular, autoimmune, and chronic airways diseases, and cancer as a result of exposure to AGEs, as well as many other ligands.


Assuntos
Produtos Finais de Glicação Avançada , Inflamação , Receptor para Produtos Finais de Glicação Avançada , Humanos , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Produtos Finais de Glicação Avançada/metabolismo , Inflamação/metabolismo , Transdução de Sinais , Neoplasias/metabolismo , Animais , Doenças Cardiovasculares/metabolismo , Doenças Neurodegenerativas/metabolismo , Doenças Metabólicas/metabolismo , Doenças Autoimunes/metabolismo
10.
J. pediatr. (Rio J.) ; J. pediatr. (Rio J.);100(supl.1): S65-S73, Mar.-Apr. 2024. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1558334

RESUMO

Abstract Objectives To review and discuss the role of an elimination diet in food-allergic children, emphasizing nutritional aspects for a better practical approach. Sources Non-systematic review of the literature. Findings Under an elimination diet, food-allergic patients may suffer from growth impairment or obesity and compromised quality of life. Disease phenotype, age, type, number of foods excluded, comorbidities, eating difficulties, economic status, and food availability must be considered for an appropriate diet prescription. Diet quality encompasses diversity and degree of food processing, which may alter immune regulation. Conclusions A friendly food elimination diet prescription depends on a multidisciplinary approach beyond macro and micronutrients.

11.
Respir Res ; 25(1): 129, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38500106

RESUMO

BACKGROUND: Acute respiratory distress syndrome (ARDS) is a common cause of respiratory failure in critically ill patients, and diffuse alveolar damage (DAD) is considered its histological hallmark. Sepsis is one of the most common aetiology of ARDS with the highest case-fatality rate. Identifying ARDS patients and differentiate them from other causes of acute respiratory failure remains a challenge. To address this, many studies have focused on identifying biomarkers that can help assess lung epithelial injury. However, there is scarce information available regarding the tissue expression of these markers. Evaluating the expression of elafin, RAGE, and SP-D in lung tissue offers a potential bridge between serological markers and the underlying histopathological changes. Therefore, we hypothesize that the expression of epithelial injury markers varies between sepsis and ARDS as well as according to its severity. METHODS: We compared the post-mortem lung tissue expression of the epithelial injury markers RAGE, SP-D, and elafin of patients that died of sepsis, ARDS, and controls that died from non-pulmonary causes. Lung tissue was collected during routine autopsy and protein expression was assessed by immunohistochemistry. We also assessed the lung injury by a semi-quantitative analysis. RESULTS: We observed that all features of DAD were milder in septic group compared to ARDS group. Elafin tissue expression was increased and SP-D was decreased in the sepsis and ARDS groups. Severe ARDS expressed higher levels of elafin and RAGE, and they were negatively correlated with PaO2/FiO2 ratio, and positively correlated with bronchopneumonia percentage and hyaline membrane score. RAGE tissue expression was negatively correlated with mechanical ventilation duration in both ARDS and septic groups. In septic patients, elafin was positively correlated with ICU admission length, SP-D was positively correlated with serum lactate and RAGE was correlated with C-reactive protein. CONCLUSIONS: Lung tissue expression of elafin and RAGE, but not SP-D, is associated with ARDS severity, but does not discriminate sepsis patients from ARDS patients.


Assuntos
Lesão Pulmonar Aguda , Síndrome do Desconforto Respiratório , Sepse , Humanos , Elafina , Proteína D Associada a Surfactante Pulmonar , Pulmão , Síndrome do Desconforto Respiratório/diagnóstico , Sepse/diagnóstico , Sepse/complicações
12.
Int J Mol Sci ; 25(5)2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38473959

RESUMO

Advanced glycation end products (AGEs) prime macrophages for lipopolysaccharide (LPS)-induced inflammation. We investigated the persistence of cellular AGE-sensitization to LPS, considering the nuclear content of p50 and p65 nuclear factor kappa B (NFKB) subunits and the expression of inflammatory genes. Macrophages treated with control (C) or AGE-albumin were rested for varying intervals in medium alone before being incubated with LPS. Comparisons were made using one-way ANOVA or Student t-test (n = 6). AGE-albumin primed macrophages for increased responsiveness to LPS, resulting in elevated levels of TNF, IL-6, and IL-1beta (1.5%, 9.4%, and 5.6%, respectively), compared to C-albumin. TNF, IL-6, and IL-1 beta secretion persisted for up to 24 h even after the removal of AGE-albumin (area under the curve greater by 1.6, 16, and 5.2 times, respectively). The expressions of Il6 and RelA were higher 8 h after albumin removal, and Il6 and Abca1 were higher 24 h after albumin removal. The nuclear content of p50 remained similar, but p65 showed a sustained increase (2.9 times) for up to 24 h in AGE-albumin-treated cells. The prolonged activation of the p65 subunit of NFKB contributes to the persistent effect of AGEs on macrophage inflammatory priming, which could be targeted for therapies to prevent complications based on the AGE-RAGE-NFKB axis.


Assuntos
Interleucina-6 , NF-kappa B , NF-kappa B/metabolismo , Interleucina-6/metabolismo , Lipopolissacarídeos/farmacologia , Macrófagos/metabolismo , Produtos Finais de Glicação Avançada/metabolismo , Albuminas/metabolismo
13.
Clinics (Sao Paulo) ; 79: 100320, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38301537

RESUMO

INTRODUCTION: Advanced Glycation End-Products (AGEs) are a diverse group of highly reactive molecules that play a vital role in the development of neurodegenerative disorders, such as Parkinson's Disease (PD), leading to a decline in functional and cognitive capacity. The objective of this study was to assess the intake and quantification of AGEs in individuals with PD and to correlate them with their functional and cognitive abilities. METHODS: This was a cross-sectional study involving 20 PD patients and 20 non-PD individuals as the Control group (C). The autofluorescence reader was used to evaluate skin AGEs, while food recall was used to quantify AGEs consumed for three different days. The Montreal Cognitive Assessment, Short Physical Performance Battery, and handgrip tests were used. PD patients demonstrated greater impairment in functional capacity compared to the control group. RESULTS: Dominant Handgrip (p = 0.02) and motor performance, in the sit and stand test (p = 0.01) and Short Physical Performance Battery (SPPB) (p = 0.01) were inferior in PD patients than the control group. Although PD patients tended to consume less AGEs than the control group, AGE intake was negatively correlated with handgrip strength in individuals with PD (r = -0.59; p < 0.05). CONCLUSION: PD patients had lower strength and functional capacity, suggesting that the effects of AGEs might be exacerbated during chronic diseases like Parkinson's.


Assuntos
Disfunção Cognitiva , Doença de Parkinson , Humanos , Estudos Transversais , Força da Mão , Cognição , Produtos Finais de Glicação Avançada
14.
J Pediatr (Rio J) ; 100 Suppl 1: S65-S73, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37918813

RESUMO

OBJECTIVES: To review and discuss the role of an elimination diet in food-allergic children, emphasizing nutritional aspects for a better practical approach. SOURCES: Non-systematic review of the literature. FINDINGS: Under an elimination diet, food-allergic patients may suffer from growth impairment or obesity and compromised quality of life. Disease phenotype, age, type, number of foods excluded, comorbidities, eating difficulties, economic status, and food availability must be considered for an appropriate diet prescription. Diet quality encompasses diversity and degree of food processing, which may alter immune regulation. CONCLUSIONS: A friendly food elimination diet prescription depends on a multidisciplinary approach beyond macro and micronutrients.


Assuntos
Hipersensibilidade Alimentar , Qualidade de Vida , Criança , Humanos , Hipersensibilidade Alimentar/prevenção & controle , Dieta , Alimentos , Dieta de Eliminação , Alérgenos
15.
Clinics ; Clinics;79: 100320, 2024. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1534238

RESUMO

Abstract Introduction Advanced Glycation End-Products (AGEs) are a diverse group of highly reactive molecules that play a vital role in the development of neurodegenerative disorders, such as Parkinson's Disease (PD), leading to a decline in functional and cognitive capacity. The objective of this study was to assess the intake and quantification of AGEs in individuals with PD and to correlate them with their functional and cognitive abilities. Methods This was a cross-sectional study involving 20 PD patients and 20 non-PD individuals as the Control group (C). The autofluorescence reader was used to evaluate skin AGEs, while food recall was used to quantify AGEs consumed for three different days. The Montreal Cognitive Assessment, Short Physical Performance Battery, and handgrip tests were used. PD patients demonstrated greater impairment in functional capacity compared to the control group. Results Dominant Handgrip (p = 0.02) and motor performance, in the sit and stand test (p = 0.01) and Short Physical Performance Battery (SPPB) (p = 0.01) were inferior in PD patients than the control group. Although PD patients tended to consume less AGEs than the control group, AGE intake was negatively correlated with handgrip strength in individuals with PD (r = -0.59; p < 0.05). Conclusion PD patients had lower strength and functional capacity, suggesting that the effects of AGEs might be exacerbated during chronic diseases like Parkinson's.

16.
Acta bioquím. clín. latinoam ; Acta bioquím. clín. latinoam;57(4): 6-6, dic. 2023. graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1556644

RESUMO

Resumen El aumento de la resistencia a los antibióticos por parte de bacterias patógenas ha motivado la búsqueda de alternativas para disminuir su utilización. Dentro de las opciones propuestas se encuentra la terapia de antiadherencia, en la cual se utilizan moléculas análogas a los glicoepítopes que son reconocidos por las bacterias para impedir la unión de éstas al tejido celular. En este estudio se llevó a cabo la obtención de glicoconjugados por medio de la reacción de Maillard partiendo de albúmina sérica bovina (BSA) y oligosacáridos de quitosano (oligosacáridos sin ultrafiltrar, ultrafiltrados y ultrafiltrados acetilados), en proporción 1:1 (p/p) a tres temperaturas de incubación (50, 60 y 70 °C) por 30 min. La caracterización de los conjugados sintetizados se realizó utilizando electroforesis (SDS-PAGE), espectroscopía de infrarrojo y espectroscopía de fluorescencia. Se realizaron ensayos de reconocimiento usando aglutinina de germen de trigo (WGA) y bacterias [Escherichia coli (K88ac y K88+)]. La caracterización por medio de electroforesis y espectroscopía de infrarrojo evidenció la unión de los oligosacáridos de quitosano a la estructura de la BSA. Además, los ensayos evidenciaron el reconocimiento de las moléculas sintetizadas tanto por la lectina WGA como por las bacterias. Los glicoconjugados sintetizados sin ultrafiltrar ni acetilar mostraron resultados muy favorables en el reconocimiento por ambas bacterias, lo que constituye una ventaja práctica, ya que su implementación a mayor escala reduciría costos de producción


Abstract The increase in antibiotic resistance by pathogenic bacteria has motivated the search for alternatives to reduce the use of antibiotics. Among these alternatives is anti-adhesion therapy, in which molecules that mimic the glycoepitopes that recognise bacteria are used to prevent their binding to cellular tissue. In this study, glycoconjugates were obtained by means of the Maillard reaction starting from bovine serum albumin (BSA) and chitosan oligosaccharides (unfiltered oligosaccharides, ultrafiltered and acetylated ultrafiltered), in a ratio of 1:1 (w/w) at three incubation temperatures (50, 60 and 70 °C) per 30 min. The characterisation was performed using the techniques of electrophoresis (SDS-PAGE), infrared spectroscopy and fluorescence spectroscopy. Recognition assays were performed using wheat germ agglutinin (WGA) and Escherichia coli bacteria (K88ac and K88+). Characterisation by electrophoresis and infrared spectroscopy demonstrated the binding of chitosan oligosaccharides to the structure of BSA. In addition, the tests showed the recognition of the molecules synthesised by both the WGA lectin and the E. coli bacteria. The glycoconjugates synthesised without ultrafiltration or acetylation showed very favourable results in recognition with both bacteria, which is an advantage, since its implementation on a larger scale would reduce production costs.


Resumo O aumento da resistência aos antibióticos por bactérias patogênicas tem motivado a busca de alterna­tivas para reduzir seu uso. Entre essas alternativas está a terapia anti-adesão, na qual são utilizadas moléculas análogas aos glicoepítopos que são reconhecidas pelas bactérias para impedir sua união ao tecido celular. Neste estudo, os glicoconjugados foram obtidos por meio da reação de Maillard a partir de albumina sérica bovina (BSA) e oligossacarídeos de quitosana (oligossacarídeos não ultra­filtrados, ultrafiltrados e acetilados ultrafiltrados), na proporção de 1:1 (p/p) em três temperaturas de incubação (50, 60 e 70 °C) durante 30 min. A caracterização dos conjugados sintetizados foi realizada utilizando a eletroforese (SDS-PAGE), espectroscopia de infravermelho e espectroscopia de fluorescência. Os ensaios de reconhecimento foram realizados utilizando aglutinina de germe de trigo (WGA) e bactérias [Escherichia coli (K88ac e K88+)]. A caracterização por meio de eletroforese e espectroscopia de infravermelho demonstrou a união dos oligossacarídeos de quitosana à estrutura da BSA. Além disso, os testes evidenciaram o reconhecimento das moléculas sintetizadas tanto pela lectina WGA quanto pelas bactérias. Os glicoconjugados sintetizados sem ultrafiltração ou acetilação apresentaram resultados muito favoráveis no reconhecimento por ambas as bactérias, o que é uma vantagem, visto que sua implementação em maior escala reduziria custos de produção.

17.
Elife ; 122023 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-37889153

RESUMO

A molecular pathway involving compounds found in processed foods and biogenic amines increases food intake and aging in the roundworm C. elegans.


Assuntos
Caenorhabditis elegans , Nematoides , Animais , Caenorhabditis elegans/metabolismo , Aminas Biogênicas/metabolismo , Hiperfagia
18.
J Neurochem ; 2023 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-37661637

RESUMO

The receptor for advanced glycation end products (RAGE) is a protein of the immunoglobulin superfamily capable of regulating inflammation. Considering the role of this receptor in the initiation and establishment of neuroinflammation, and the limited understanding of the function of RAGE in the maintenance of this condition, this study describes the effects of RAGE inhibition in the brain, through an intranasal treatment with the antagonist FPS-ZM1, in an animal model of chronic neuroinflammation induced by acute intraperitoneal injection of lipopolysaccharide (LPS). Seventy days after LPS administration (2 mg/kg, i.p.), Wistar rats received, intranasally, 1.2 mg of FPS-ZM1 over 14 days. On days 88 and 89, the animals were submitted to the open-field test and were killed on day 90 after the intraperitoneal injection of LPS. Our results indicate that blockade of encephalic RAGE attenuates LPS-induced chronic neuroinflammation in different brain regions. Furthermore, we found that intranasal FPS-ZM1 administration reduced levels of gliosis markers, RAGE ligands, and α-synuclein in the substantia nigra pars compacta. Additionally, the treatment also reversed the increase in S100 calcium-binding protein B (RAGE ligand) in the cerebrospinal fluid and the cognitive-behavioral deficits promoted by LPS-less time spent in the central zone of the open-field arena (more time in the lateral zones), decreased total distance traveled, and increased number of freezing episodes. In summary, our study demonstrates the prominent role of RAGE in the maintenance of a chronic neuroinflammatory state triggered by a single episode of systemic inflammation and also points to possible future RAGE-based therapeutic approaches to treat conditions in which chronic neuroinflammation and increased α-synuclein levels could play a relevant role, such as in Parkinson's disease.

19.
Crit Rev Food Sci Nutr ; : 1-11, 2023 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-37632425

RESUMO

Ultra-high temperature (UHT) treatments are of high economic relevance for food industries because they contribute to extending the shelf life of food products and facilitating their distribution. In the dairy segment, UHT treatments are applied to a wide range of products containing variable protein amounts. In this sense, the changes in the molecular structure of milk proteins induced by the severity of UHT treatments may lead to fouling in equipment during processing or sedimentation and/or gelation during storage. Nowadays, these concerns are even more relevant due to the increasing demand for UHT-treated high-protein beverages. This review will discuss the two main strategies used by industries to increase the stability of milk proteins during and/or after UHT treatments: (i) addition of chelating agents and (ii) use of polysaccharides. Moreover, the challenges and opportunities associated with promising strategies to improve the stability of milk proteins during and/or after UHT treatments will be covered in this review. The information compiled will be useful to guide researchers and industries in developing more stable UHT dairy products in harmony with consumers' demands.

20.
World J Diabetes ; 14(7): 977-994, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37547586

RESUMO

Obesity and type 2 diabetes mellitus (T2DM) are chronic pathologies with a high incidence worldwide. They share some pathological mechanisms, including hyperinsulinemia, the production and release of hormones, and hyperglycemia. The above, over time, affects other systems of the human body by causing tissue hypoxia, low-grade inflammation, and oxidative stress, which lay the pathophysiological groundwork for cancer. The leading causes of death globally are T2DM and cancer. Other main alterations of this pathological triad include the accumulation of advanced glycation end products and the release of endogenous alarmins due to cell death (i.e., damage-associated molecular patterns) such as the intracellular proteins high-mobility group box protein 1 and protein S100 that bind to the receptor for advanced glycation products (RAGE) - a multiligand receptor involved in inflammatory and metabolic and neoplastic processes. This review analyzes the latest advanced reports on the role of RAGE in the development of obesity, T2DM, and cancer, with an aim to understand the intracellular signaling mechanisms linked with cancer initiation. This review also explores inflammation, oxidative stress, hypoxia, cellular senescence, RAGE ligands, tumor microenvironment changes, and the "cancer hallmarks" of the leading tumors associated with T2DM. The assimilation of this information could aid in the development of diagnostic and therapeutic approaches to lower the morbidity and mortality associated with these diseases.

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