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1.
Pure Appl Geophys ; 179(1): 105-123, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35068593

RESUMO

The phase-velocity dispersion curve (DC) is an important characteristic of the propagation of surface waves in sedimentary environments. Although the procedure for DC estimation in onshore environments using ambient vibration recordings is well established, the DC estimation in offshore environments using Ocean Bottom Seismometers (OBS) array recordings of ambient vibrations presents three additional challenges: (1) the localization of sensors, (2) the orientation of the OBS horizontal components, and (3) the clock error. Here, we address these challenges in an inherent preprocessing workflow to ultimately extract the Love and Scholte wave DC from small aperture OBS array measurements performed between 2018 and 2020 in Lake Lucerne (Switzerland). The arrays have a maximum aperture of 679 m and a maximum deployment water depth of 81 m. The challenges related to the OBS location on the lake floor are addressed by combining the multibeam bathymetry map and the backscatter image for the investigated site with the differential GPS coordinates of the OBS at recovery. The OBS measurements are complemented by airgun surveys. Airgun data are first used to estimate the misorientation of the horizontal components of the OBS and second to estimate the clock error. To assess the robustness of the preprocessing workflow, we use two array processing methods, namely the three-component high-resolution frequency-wavenumber and the interferometric multichannel analysis of surface waves, to estimate the dispersion characteristics of the propagating Scholte and Love waves for one of the OBS array sites. The results show the effectiveness of the preprocessing workflow. We observe the phase-velocity dispersion curve branches in the frequency range between 1.2 and 3.2 Hz for both array processing techniques. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s00024-021-02923-8.

2.
Anal Biochem ; 592: 113584, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31953047

RESUMO

Celiac disease (CD) is a chronic immune-mediated disease in which gluten ingestion leads to damage of the small intestinal mucosa in genetically susceptible individuals. The enteropathy is mainly induced by the production of IFN-γ from intestinal CD4+T cells that recognise gliadin peptides following deamidation by tissue transglutaminase. The only available therapy is a strict, lifelong gluten-free diet (GFD). This diet is strongly demanding for patients, which justifies the search for alternative strategies. The enzyme approach is one promising strategy to address this issue. In particular, transamidation of wheat gliadin by microbial transglutaminase (mTG) was fully effective at inhibiting gliadin-specific IFN-γ secretion in intestinal T cells from CD patients. Furthermore, transamidated gliadin induced higher levels of the anti-inflammatory IL-10 than native gliadin in different in vitro models. These data suggest that a more balanced immune response could be induced by mTG-treated gliadin in the small intestine of celiac patients. Furthermore, the highlighted biological property of mTG-treated gliadin could be exploited to induce tolerance to native gliadin in at-risk individuals.


Assuntos
Linfócitos T CD4-Positivos/efeitos dos fármacos , Doença Celíaca/tratamento farmacológico , Gliadina/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Transglutaminases , Triticum , Bactérias/enzimologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/patologia , Farinha , Humanos , Interleucina-10/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Transglutaminases/farmacologia , Transglutaminases/uso terapêutico , Triticum/efeitos dos fármacos , Triticum/metabolismo
3.
Nutr Neurosci ; 23(4): 309-320, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30039750

RESUMO

Objectives: A strong rise of the fructose content in the human diet occurred in the last decade, as corn syrup is widely used as a sweetener for beverages and processed food. Since young people make a widespread consumption of added sugars, we evaluated the effects of a two weeks fructose-rich diet on brain redox homeostasis, autophagy and synaptic plasticity in the cortex of young and adults rats, in order to highlight the early risks to which brain is exposed.Methods and Results: Short-term fructose feeding was associated with an imbalance of redox homeostasis, as lower amount of Nuclear factor (erythroid derived 2)-like 2, lower activity of Glucose 6-phosphate dehydrogenase and Glutathione reductase, together with lower Glutathione/Oxidized Glutathione ratio, were found in fructose-fed young and adult rats. Fructose-rich diet was also associated with the activation of autophagy, as higher levels of Beclin, LC3 II and P62 were detected in cortex of fructose-fed rats. A diet associated decrease of synaptophysin, synapsin I, and synaptotagmin I, was found in fructose-fed young and adult rats. Interestingly, BDNF amount was significantly lower only in fructose-fed adult rats, while the level of its receptor TrkB decreased in both groups of treated rats. A further marker of brain functioning, Acetylcholinesterase activity, was found increased only in fructose-fed young animals.Conclusion: Overall, our findings suggest that young rats may severely suffer from the deleterious influence of fructose on brain health as the adults and provide experimental data suggesting the need of targeted nutritional strategies to reduce its amount in foods.


Assuntos
Autofagia/efeitos dos fármacos , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Frutose/administração & dosagem , Fator 2 Relacionado a NF-E2/metabolismo , Sinapses/efeitos dos fármacos , Sinapses/metabolismo , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Masculino , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Estresse Oxidativo , Ratos Sprague-Dawley , Receptor trkB/metabolismo , Transdução de Sinais/efeitos dos fármacos
4.
Nutr Res Rev ; 33(1): 90-101, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31615587

RESUMO

Mitochondria play an important role in a number of fundamental cellular processes, including energy production, biosynthetic pathways and cellular oxidoreductive homeostasis (redox status), and their dysfunction can lead to numerous pathophysiological consequences. As the biochemical mechanisms orchestrating mitochondrial metabolism and redox homeostasis are functionally linked, mitochondria have been identified as a potential therapeutic target. Consequently, considerable effort has been made to evaluate the efficacy of natural compounds that modulate mitochondrial function. Molecules produced by plants (for example, polyphenols and isothiocyanates) have been shown to modulate mitochondrial metabolism/biogenesis and redox status; however, despite the existence of a functional link, few studies have considered the combined efficacy of these mitochondrial functions. The present review provides a complete overview of the molecular pathways involved in modulating mitochondrial metabolism/biogenesis and redox status. Crosstalk between these critical mechanisms is also discussed, whilst major data from the literature regarding their antioxidant abilities are described and critically analysed. We also provide a summary of recent evidence regarding the ability of several plant-derived compounds to target these mitochondrial functions. An in-depth understanding of the functional link between mitochondrial metabolism/biogenesis and redox status could facilitate the analysis of the biological effects of natural compounds as well as the development of new therapeutic approaches.


Assuntos
Mitocôndrias , Polifenóis , Homeostase , Humanos , Mitocôndrias/metabolismo , Oxirredução , Estresse Oxidativo , Polifenóis/metabolismo , Polifenóis/farmacologia , Espécies Reativas de Oxigênio/metabolismo
5.
J Lipid Res ; 59(1): 48-57, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29167408

RESUMO

Oxidative stress is a key mediator of autoimmune/neurodegenerative disorders. The antioxidant/anti-inflammatory effect of a synthetic conjugated linoleic acid (CLA) mixture in MRL/MpJ-Fas lpr mice (MRL/lpr), an animal model of neuropsychiatric lupus, was previously associated with the improvement of nuclear factor-E2-related factor 2 (Nrf2) defenses in the spleen and liver. However, little is known about the neuroprotective ability of a CLA mixture. This study investigated the age-dependent progression of oxidative stress and the hyperactivation of redox-sensitive compensatory pathways (macroautophagy, Nrf2) in old/diseased MRL/lpr mice brains and examines the effect produced by dietary CLA supplementation. Disrupted redox homeostasis was evidenced in the blood, liver, and brain of 21- to 22-week-old MRL/lpr (Old) mice compared with 8- to 10-week-old MRL/lpr (Young) animals. This alteration was associated with significant hyperactivation of compensatory mechanisms (macroautophagy, Nrf2, and astrocyte activation) in the brains of Old mice. Five-week daily supplementation with CLA (650 mg/kg-1 body weight) of 16-week-old (CLA+Old) mice diminished all the pathological hallmarks at a level comparable to Young mice or healthy controls (BALB/c). Such data demonstrated that MRL/lpr mice can serve as a valuable model for the evaluation of the effectiveness of neuroprotective drugs. Notably, the preventive effect provided by CLA supplementation against age-associated neuronal damage and hyperactivation of compensatory mechanisms suggests that the activation of an adaptive response is at least in part accountable for its neuroprotective ability.


Assuntos
Modelos Animais de Doenças , Ácidos Linoleicos Conjugados/farmacologia , Lúpus Eritematoso Sistêmico/prevenção & controle , Administração Oral , Fatores Etários , Animais , Feminino , Ácidos Linoleicos Conjugados/administração & dosagem , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Degeneração Neural/metabolismo , Estresse Oxidativo/efeitos dos fármacos
6.
Cytokine ; 90: 80-87, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27863334

RESUMO

Enterocytes are actively involved in the defense against pathogens and they limit penetration of commensal microbes into tissues. They also have an important role in gut immunity as enterocytes confer mucosal dendritic cell specialisation. On the other hand, the microbiota is directly involved in the development and modulation of the intestinal immune system. Particularly, lactobacilli and bifidobacteria play a primary role in shaping the immune response. We further explored this issue by evaluating whether functional differences in Caco-2 cells could characterise faecal populations of lactobacilli (155 samples) and bifidobacteria (110 samples) isolated from three dietary cohorts (omnivores, ovo-lacto-vegetarians and vegans) recruited at four Italian centres (Turin, Parma, Bologna and Bari). According to our findings, tested bacteria were unable to modulate expression of IL-8, IL-10, TGF-ß or thymic stromal lymphopoietin (TSLP) cytokines in unstimulated Caco-2 cells. Conversely, in phorbol 12-myristate 13-acetate and ionomycin (PMA/Io) stimulated Caco-2 cells, lactobacilli from the omnivorous group and all bifidobacteria significantly down-regulated IL-8. Notably, both genera also lowered the TSLP expression in stimulated Caco-2 cells, regardless of the diet regimen. By further examining these data on the basis of geographical origin, we found that lactobacilli from the vegetarian group recruited in Bari, significantly up-regulated this cytokine. In conclusion, we highlighted a peculiar immune-modulatory activity profile for lactobacilli on enterocytes undergoing a stimulatory signal, which was associated with a specific dietary habit. Furthermore, the geographical area had a significant impact on the inflammatory potential of members of the Lactobacillus genus.


Assuntos
Bifidobacterium/imunologia , Citocinas/imunologia , Comportamento Alimentar , Preferências Alimentares , Interleucina-8/imunologia , Lactobacillus/imunologia , Adolescente , Adulto , Bifidobacterium/isolamento & purificação , Células CACO-2 , Feminino , Humanos , Lactobacillus/isolamento & purificação , Masculino , Pessoa de Meia-Idade , Acetato de Tetradecanoilforbol/farmacologia , Linfopoietina do Estroma do Timo
7.
J Biol Chem ; 290(5): 2902-18, 2015 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-25505251

RESUMO

Gut microbial metabolites of polyunsaturated fatty acids have attracted much attention because of their various physiological properties. Dysfunction of tight junction (TJ) in the intestine contributes to the pathogenesis of many disorders such as inflammatory bowel disease. We evaluated the effects of five novel gut microbial metabolites on tumor necrosis factor (TNF)-α-induced barrier impairment in Caco-2 cells and dextran sulfate sodium-induced colitis in mice. 10-Hydroxy-cis-12-octadecenoic acid (HYA), a gut microbial metabolite of linoleic acid, suppressed TNF-α and dextran sulfate sodium-induced changes in the expression of TJ-related molecules, occludin, zonula occludens-1, and myosin light chain kinase. HYA also suppressed the expression of TNF receptor 2 (TNFR2) mRNA and protein expression in Caco-2 cells and colonic tissue. In addition, HYA suppressed the protein expression of TNFR2 in murine intestinal epithelial cells. Furthermore, HYA significantly up-regulated G protein-coupled receptor (GPR) 40 expression in Caco-2 cells. It also induced [Ca(2+)]i responses in HEK293 cells expressing human GPR40 with higher sensitivity than linoleic acid, its metabolic precursor. The barrier-recovering effects of HYA were abrogated by a GPR40 antagonist and MEK inhibitor in Caco-2 cells. Conversely, 10-hydroxyoctadacanoic acid, which is a gut microbial metabolite of oleic acid and lacks a carbon-carbon double bond at Δ12 position, did not show these TJ-restoring activities and down-regulated GPR40 expression. Therefore, HYA modulates TNFR2 expression, at least partially, via the GPR40-MEK-ERK pathway and may be useful in the treatment of TJ-related disorders such as inflammatory bowel disease.


Assuntos
Células Epiteliais/metabolismo , Intestinos/citologia , Ácido Linoleico/metabolismo , Ácidos Oleicos/metabolismo , Animais , Células CACO-2 , Colite/metabolismo , Células Epiteliais/citologia , Feminino , Citometria de Fluxo , Humanos , Imuno-Histoquímica , Sistema de Sinalização das MAP Quinases/fisiologia , Camundongos , Camundongos Endogâmicos BALB C , Receptores Acoplados a Proteínas G/metabolismo
8.
Eur J Nutr ; 55(2): 729-740, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25840667

RESUMO

PURPOSE: The beneficial effects of conjugated linoleic acid (CLA) mixture (cis9, trans11, c9; trans10, cis12, t10) against gliadin-induced toxicity in HLA-DQ8-transgenic mice (DQ8) have been associated with improved duodenal cytoprotective mechanisms [nuclear factor-E2-related factor-2, Nrf2; acylpeptide hydrolase (APEH)/proteasome]. The present study was aimed at investigating the ability of individual CLA isomers to improve the efficacy of these defensive mechanisms and to protect against duodenal injury caused by the combined administration of gliadin and indomethacin (GI). METHODS: Gluten-mediated enteropathy was induced in DQ8 mice by three intra-gastric administration of gliadin (20 mg kg(-1)/bw) and indomethacin (15 mg L(-1)) in drinking water for 10 days (GI). C9 or t10 CLA (520 mg kg(-1)/bw/day) were orally administered for 2 weeks. Pro-oxidant and toxic effects associated with GI treatment, anti-oxidant/detoxifying ability of c9 or t10-CLA and the protective effect induced by c9 pre-treatment (c9 + GI) were evaluated in DQ8 mice duodenum by combining enzymatic, immunoblotting, histological evaluation and quantitative real-time PCR assays. RESULTS: GI treatment produces the time-dependent decline of the considered detoxifying mechanisms thus leading to pro-apoptotic and pro-oxidant effects. APEH/proteasome pathway was not markedly affected by individual CLA isomers, but duodenal redox status and activity/mRNA levels of Nrf2-activated enzymes were significantly improved by c9 administration. c9 pre-treatment protects against GI-mediated accumulation of oxidative stress markers, and histological examination reveals the increase of goblet cells number in mouse duodenum but induces only a partial recovery of APEH/proteasome activity. CONCLUSIONS: The activation of and adaptive response by low doses of c9 supplementation prevents distinct signs of gliadin-induced enteropathy in DQ8 mice.


Assuntos
Doença Celíaca/tratamento farmacológico , Gliadina/efeitos adversos , Ácidos Linoleicos Conjugados/administração & dosagem , Animais , Doença Celíaca/induzido quimicamente , Relação Dose-Resposta a Droga , Indometacina/efeitos adversos , Camundongos , Camundongos Transgênicos , NAD(P)H Desidrogenase (Quinona)/genética , NAD(P)H Desidrogenase (Quinona)/metabolismo , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Peptídeo Hidrolases/genética , Peptídeo Hidrolases/metabolismo , Espécies Reativas de Oxigênio/metabolismo
9.
J Lipid Res ; 55(5): 837-49, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24634500

RESUMO

Oxidative stress, hepatic steatosis, and mitochondrial dysfunction are key pathophysiological features of nonalcoholic fatty liver disease. A conjugated linoleic acid (CLA) mixture of cis9,trans11 (9,11-CLA) and trans10,cis12 (10,12-CLA) isomers enhanced the antioxidant/detoxifying mechanism via the activation of nuclear factor E2-related factor-2 (Nrf2) and improved mitochondrial function, but less is known about the actions of specific isomers. The differential ability of individual CLA isomers to modulate these pathways was explored in Wistar rats fed for 4 weeks with a lard-based high-fat diet (L) or with control diet (CD), and, within each dietary treatment, two subgroups were daily administered with 9,11-CLA or 10,12-CLA (30 mg/day). The 9,11-CLA, but not 10,12-CLA, supplementation to CD rats improves the GSH/GSSG ratio in the liver, mitochondrial functions, and Nrf2 activity. Histological examination reveals a reduction of steatosis in L-fed rats supplemented with both CLA isomers, but 9,11-CLA downregulated plasma concentrations of proinflammatory markers, mitochondrial dysfunction, and oxidative stress markers in liver more efficiently than in 10,12-CLA treatment. The present study demonstrates the higher protective effect of 9,11-CLA against diet-induced pro-oxidant and proinflammatory signs and suggests that these effects are determined, at least in part, by its ability to activate the Nrf2 pathway and to improve the mitochondrial functioning and biogenesis.


Assuntos
Canais Iônicos/metabolismo , Ácidos Linoleicos Conjugados/farmacologia , Proteínas Mitocondriais/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Animais , Biomarcadores/metabolismo , Citocinas/metabolismo , Citoproteção/efeitos dos fármacos , Dieta Hiperlipídica/efeitos adversos , Suplementos Nutricionais , Regulação da Expressão Gênica/efeitos dos fármacos , Ácidos Linoleicos Conjugados/química , Ácidos Linoleicos Conjugados/uso terapêutico , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Hepatopatia Gordurosa não Alcoólica/induzido quimicamente , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Oxirredução/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos , Proteína Desacopladora 1
10.
Biochim Biophys Acta ; 1830(11): 5166-74, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23891939

RESUMO

BACKGROUND: Celiac disease (CD) is an immune-mediated disorder caused by the ingestion of wheat gluten. A lifelong, gluten-free diet is required to normalize the intestinal mucosa. We previously found that transamidation by microbial transglutaminase (mTGase) suppressed the gliadin-specific immune response in intestinal T-cell lines from CD patients and in models of gluten sensitivity. METHODS: SDS-PAGE, Western blot, ELISA, tissue transglutaminase (tTGase) assay and nano-HPLC-ESI-MS/MS experiments were used to analyze prolamins isolated from treated wheat flour. RESULTS: Gliadin and glutenin yields decreased to 7.6±0.5% and 7.5±0.3%, respectively, after a two-step transamidation reaction that produced a water-soluble protein fraction (spf). SDS-PAGE, Western blot and ELISA analyses confirmed the loss of immune cross-reactivity with anti-native gliadin antibodies in residual transamidated gliadins (K-gliadins) and spf as well as the occurrence of neo-epitopes. Nano-HPLC-ESI-MS/MS experiments identified some native and transamidated forms of celiacogenic peptides including p31-49 and confirmed that mTGase had similar stereo-specificity of tTGase. Those peptides resulted to be 100% and 57% modified in spf and K-gliadins, respectively. In particular, following transamidation p31-49 lost its ability to increase tTGase activity in Caco-2 cells. Finally, bread manufactured with transamidated flour had only minor changes in baking characteristics. CONCLUSIONS: The two-step transamidation reaction modified the analyzed gliadin peptides, which are known to trigger CD, without influencing main technological properties. GENERAL SIGNIFICANCE: Our data shed further light on a detoxification strategy alternative to the gluten free diet and may have important implications for the management of CD patients.


Assuntos
Farinha , Gliadina/metabolismo , Transglutaminases/metabolismo , Triticum/metabolismo , Sequência de Aminoácidos , Células CACO-2 , Linhagem Celular Tumoral , Gliadina/química , Glutens/metabolismo , Humanos , Dados de Sequência Molecular , Peptídeos/metabolismo , Transglutaminases/química
11.
Am J Physiol Gastrointest Liver Physiol ; 307(3): G302-12, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-24924747

RESUMO

Celiac disease (CD) is an enteropathy caused by the ingestion of wheat gluten in genetically susceptible individuals. A complete understanding of the pathogenic mechanisms in CD has been hindered because of the lack of adequate in vivo models. In the present study, we explored the events after the intragastric administration of gliadin and of the albumin/globulin fraction from wheat in human leukocyte antigen-DQ8 transgenic mice (DQ8 mice) treated with indomethacin, an inhibitor of cyclooxygenases (COXs). After 10 days of treatment, mice showed a significant reduction of villus height, increased crypt depth, increased number of lamina propria-activated macrophages, and high basal interferon-γ secretion in mesenteric lymph nodes, all of which were specifically related to gliadin intake, whereas the albumin/globulin fraction of wheat was unable to induce similar changes. Cotreatment with NS-398, a specific inhibitor of COX-2, also induced the intestinal lesion. Enteropathy onset was further characterized by high levels of oxidative stress markers, similar to CD. Biochemical assessment of the small intestine revealed the specific activation of matrix metalloproteinases 2 and 9, high caspase-3 activity, and a significant increase of tissue transglutaminase protein levels associated with the intestinal lesion. Notably, after 30 days of treatment, enteropathic mice developed serum antibodies toward gliadin (IgA) and tissue transglutaminase (IgG). We concluded that gliadin intake in combination with COX inhibition caused a basal inflammatory status and an oxidative stress condition in the small intestine of DQ8 mice, thus triggering the mucosal lesion and, subsequently, an antigen-specific immunity.


Assuntos
Doença Celíaca/induzido quimicamente , Inibidores de Ciclo-Oxigenase 2/toxicidade , Ciclo-Oxigenase 2/metabolismo , Gliadina , Antígenos HLA-DQ/metabolismo , Indometacina/toxicidade , Mucosa Intestinal/efeitos dos fármacos , Intestino Delgado/efeitos dos fármacos , Animais , Apoptose , Caspase 3/metabolismo , Doença Celíaca/genética , Doença Celíaca/imunologia , Doença Celíaca/metabolismo , Doença Celíaca/patologia , Modelos Animais de Doenças , Proteínas de Ligação ao GTP/imunologia , Proteínas de Ligação ao GTP/metabolismo , Gliadina/imunologia , Antígenos HLA-DQ/genética , Humanos , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Mucosa Intestinal/imunologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Intestino Delgado/imunologia , Intestino Delgado/metabolismo , Intestino Delgado/patologia , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Camundongos Transgênicos , Nitrobenzenos/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Proteína 2 Glutamina gama-Glutamiltransferase , Sulfonamidas/toxicidade , Fatores de Tempo , Transglutaminases/imunologia , Transglutaminases/metabolismo
12.
BMC Microbiol ; 13: 298, 2013 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-24365457

RESUMO

BACKGROUND: Probiotics species appear to differentially regulate the intestinal immune response. Moreover, we have shown that different immune-modulatory abilities can be found among probiotic strains belonging to the same species. In this study, we further addressed this issue while studying L. gasseri, a species that induces relevant immune activities in human patients. RESULTS: We determined the ability of two strains of L. gasseri, OLL2809 and L13-Ia, to alter cell surface antigen expression, cytokine production and nuclear erythroid 2-related factor 2 (Nrf2)-mediated cytoprotection in murine bone marrow-derived dendritic cells (DCs) and MODE-K cells, which represent an enterocyte model. Differential effects of L. gasseri strains were observed on the expression of surface markers in mature DCs; nevertheless, both strains dramatically induced production of IL-12, TNF-α and IL-10. Distinctive responses to OLL2809 and L13-Ia were also shown in MODE-K cells by analyzing the expression of MHC II molecules and the secretion of IL-6; however, both L. gasseri strains raised intracellular glutathione. Treatment of immature DCs with culture medium from MODE-K monolayers improved cytoprotection and modified the process of DC maturation by down-regulating the expression of co-stimulatory markers and by altering the cytokine profile. Notably, bacteria-conditioned MODE-K cell medium suppressed the expression of the examined cytokines, whereas cytoprotective defenses were significantly enhanced only in DCs exposed to OLL2809-conditioned medium. These effects were essentially mediated by secreted bacterial metabolites. CONCLUSIONS: We have demonstrated that L. gasseri strains possess distinctive abilities to modulate in vitro DCs and enterocytes. In particular, our results highlight the potential of metabolites secreted by L. gasseri to influence enterocyte-DC crosstalk. Regulation of cellular mechanisms of innate immunity by selected probiotic strains may contribute to the beneficial effects of these bacteria in gut homeostasis.


Assuntos
Imunidade Inata , Fatores Imunológicos/farmacologia , Lactobacillus/imunologia , Probióticos/farmacologia , Animais , Antígenos de Superfície/metabolismo , Células Cultivadas , Citocinas/metabolismo , Células Dendríticas/imunologia , Células Dendríticas/microbiologia , Enterócitos/imunologia , Enterócitos/microbiologia , Camundongos , Fator 2 Relacionado a NF-E2/metabolismo
13.
Antioxidants (Basel) ; 12(5)2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37237938

RESUMO

The maintenance of redox homeostasis is associated with a healthy status while the disruption of this mechanism leads to the development of various pathological conditions. Bioactive molecules such as carbohydrates accessible to the microbiota (MACs), polyphenols, and polyunsaturated fatty acids (PUFAs) are food components best characterized for their beneficial effect on human health. In particular, increasing evidence suggests that their antioxidant ability is involved in the prevention of several human diseases. Some experimental data indicate that the activation of the nuclear factor 2-related erythroid 2 (Nrf2) pathway-the key mechanism in the maintenance of redox homeostasis-is involved in the beneficial effects exerted by the intake of PUFAs and polyphenols. However, it is known that the latter must be metabolized before becoming active and that the intestinal microbiota play a key role in the biotransformation of some ingested food components. In addition, recent studies, indicating the efficacy of the MACs, polyphenols, and PUFAs in increasing the microbial population with the ability to yield biologically active metabolites (e.g., polyphenol metabolites, short-chain fatty acids (SCFAs)), support the hypothesis that these factors are responsible for the antioxidant action on the physiology of the host. The underlying mechanisms through which MACs, polyphenols, and PUFAs might influence the redox status have not been fully elucidated, but based on the efficacy of SCFAs as Nrf2 activators, their contribution to the antioxidant efficacy of dietary bioactives cannot be excluded. In this review, we aimed to summarize the main mechanisms through which MACs, polyphenols, and PUFAs can modulate the host's redox homeostasis through their ability to directly or indirectly activate the Nrf2 pathway. We discuss their probiotic effects and the role played by the alteration of the metabolism/composition of the gut microbiota in the generation of potential Nrf2-ligands (e.g., SCFAs) in the host's redox homeostasis.

14.
Clin Dev Immunol ; 2012: 329150, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22899947

RESUMO

A lifelong gluten-free diet (GFD) is mandatory for celiac disease (CD) but has poor compliance, justifying novel strategies. We found that wheat flour transamidation inhibited IFN-γ secretion by intestinal T cells from CD patients. Herein, the primary endpoint was to evaluate the ability of transamidated gluten to maintain GFD CD patients in clinical remission. Secondary endpoints were efficacy in prevention of the inflammatory response and safety at the kidney level, where reaction products are metabolized. In a randomized single blinded, controlled 90-day trial, 47 GFD CD patients received 3.7 g/day of gluten from nontransamidated (12) or transamidated (35) flour. On day 15, 75% and 37% of patients in the control and experimental groups, respectively, showed clinical relapse (P = 0.04) whereas intestinal permeability was mainly altered in the control group (50% versus 20%, P = 0.06). On day 90, 0 controls and 14 patients in the experimental group completed the challenge with no variation of antitransglutaminase IgA (P = 0.63), Marsh-Oberhuber grading (P = 0.08), or intestinal IFN-γ mRNA (P > 0.05). Creatinine clearance did not vary after 90 days of treatment (P = 0.46). In conclusion, transamidated gluten reduced the number of clinical relapses in challenged patients with no changes of baseline values for serological/mucosal CD markers and an unaltered kidney function.


Assuntos
Doença Celíaca/dietoterapia , Dieta Livre de Glúten , Proteínas Alimentares/administração & dosagem , Farinha , Glutens/administração & dosagem , Triticum/metabolismo , Adolescente , Adulto , Amidinotransferases/imunologia , Autoanticorpos/sangue , Doença Celíaca/imunologia , Ingestão de Alimentos , Feminino , Humanos , Interferon gama/metabolismo , Mucosa Intestinal/imunologia , Masculino , Pessoa de Meia-Idade , Cooperação do Paciente , Método Simples-Cego , Transglutaminases/metabolismo , Triticum/química , Adulto Jovem
15.
Nat Hazards (Dordr) ; 113(1): 475-505, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35915597

RESUMO

Tsunamis occur not only in marine settings but also in lacustrine environments. Most of the lacustrine tsunamis are caused by seismically- or aseismically-triggered mass movements. Therefore, an assessment of the stability of subaqueous slopes is crucial for tsunami hazard assessment in a lake. We selected Lake Lucerne (Switzerland) as a natural laboratory to perform an in-depth geotechnical characterization of its subaqueous slopes. This lake experienced documented tsunamis in 1601 and 1687. Some of its slopes still bear sediment volumes with a potential for tsunamigenic failure. To identify such slopes, we interpreted available reflection seismic data and analyzed the bathymetric map. Then, we performed 152 dynamic Cone Penetration Tests with pore pressure measurement (CPTu) and retrieved 49 sediment cores at different locations in the lake. These data were used to characterize the failure-prone sediments and to evaluate the present-day static stability of subaqueous slopes. Obtained results allowed the definition of three classes of slopes in terms of static stability: unstable slopes, stable slopes close to the unstable state, and stable areas. Non-deltaic slopes with thicker unconsolidated fine-grained sediment drape and moderate-to-high slope gradients (> 5-10°) have the lowest Factor of Safety. In agreement with previous studies, the failure plane for the non-deltaic slopes is embedded within the fine-grained glaciolacustrine sediments. Deltaic slopes with prevailing coarse-grained sediments mostly appear statically stable. Finally, we generalized the measured undrained shear strength profiles s u ( z ) into the depth-dependent power-law models. These models define the s u of Lake Lucerne's sediments and can be applied to other lakes with similar sedimentation history. Supplementary Information: The online version contains supplementary material available at 10.1007/s11069-022-05310-1.

16.
Eur Urol Focus ; 8(1): 351-359, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33579652

RESUMO

BACKGROUND: Human semen quality is affected by lifestyle and environmental factors. OBJECTIVE: To evaluate the short-term effects of a diet and physical activity intervention on semen quality of healthy young men living in highly polluted areas of Italy. DESIGN, SETTING, AND PARTICIPANTS: A randomized controlled trial was conducted. Healthy young men were assigned to an intervention or a control group. INTERVENTION: A 4-mo Mediterranean diet and moderate physical activity program. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary outcomes were sperm concentration, motility and morphology, concentration of round cells, and semen total antioxidant capacity. Secondary outcomes were adherence to Mediterranean diet and physical activity. All outcomes were measured twice, at the enrollment (t0) and at the end of the intervention (t4). RESULTS AND LIMITATIONS: A total of 263 individuals attended all visits, and underwent examinations and laboratory analyses: 137 in the intervention group and 126 in the control group. The adherence to Mediterranean diet and physical activity level increased more in the intervention group than in the control group from t0 to t4. Sperm concentration, total and progressive motility, and proportion of normal morphology cells increased in the intervention group but decreased in the control group, with statistically significant differences between the two groups at t4. The total antioxidant capacity increased in the intervention group but decreased in the control group, from t0 to t4. CONCLUSIONS: Study results showed that an intervention based on Mediterranean diet and regular physical activity can determine an improvement of semen quality in healthy young men. PATIENT SUMMARY: Our study aimed to evaluate the effect of a lifestyle intervention on semen quality of healthy young men. We assigned the 263 enrolled individuals to an intervention or a control group. The intervention group followed a 4-mo Mediterranean diet and moderate physical activity program, at the end of which the participants showed an improvement of semen quality parameters.


Assuntos
Dieta Mediterrânea , Análise do Sêmen , Antioxidantes , Humanos , Estilo de Vida , Masculino , Contagem de Espermatozoides
17.
Nutrients ; 13(4)2021 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-33800688

RESUMO

Milk contains several important nutrients that are beneficial for human health. This review considers the nutritional qualities of essential fatty acids (FAs), especially omega-3 (ω-3) and omega-6 (ω-6) polyunsaturated fatty acids (PUFAs) present in milk from ruminant and non-ruminant species. In particular, the impact of milk fatty acids on metabolism is discussed, including its effects on the central nervous system. In addition, we presented data indicating how animal feeding-the main way to modify milk fat composition-may have a potential impact on human health, and how rearing and feeding systems strongly affect milk quality within the same animal species. Finally, we have presented the results of in vivo studies aimed at supporting the beneficial effects of milk FA intake in animal models, and the factors limiting their transferability to humans were discussed.


Assuntos
Ácidos Graxos Essenciais/análise , Ácidos Graxos Ômega-3/análise , Ácidos Graxos Ômega-6/análise , Leite/química , Ração Animal , Animais , Encéfalo/metabolismo , Comportamento Alimentar/fisiologia , Humanos , Fenômenos Fisiológicos da Nutrição/fisiologia
18.
Antioxidants (Basel) ; 10(11)2021 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-34829678

RESUMO

The biological mechanisms linking nutrition and antioxidants content of the diet with cardiovascular protection are subject of intense investigation. It has been demonstrated that dietary supplementation with cow, donkey or human milk, characterized by distinct nutritional properties, triggers significant differences in the metabolic and inflammatory status through the modulation of hepatic and skeletal muscle mitochondrial functions. Cardiac mitochondria play a key role for energy-demanding heart functions, and their disfunctions is leading to pathologies. Indeed, an altered heart mitochondrial function and the consequent increased reactive oxygen species (ROS) production and inflammatory state, is linked to several cardiac diseases such as hypertension and heart failure. In this work it was investigated the impact of the milk consumption on heart mitochondrial functions, inflammation and oxidative stress. In addition, it was underlined the crosstalk between mitochondrial metabolic flexibility, lipid storage and redox status as control mechanisms for the maintenance of cardiovascular health.

19.
Food Funct ; 12(13): 5903-5912, 2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34028481

RESUMO

Alternative or complementary treatments to a gluten-free diet are urgently needed for Celiac Disease. By exploiting the health-promoting properties of polyphenols on a transgenic mouse model of Celiac Disease enteropathy, this study provides the first in vivo evidence regarding the ability of 1 mg day-1 doses of green tea catechins and grape seed procyanidins to ameliorate some of the most characteristic histological changes of gliadin-treated DQ8 mice, including villus flattening, crypt hyperplasia, and infiltration of intraepithelial lymphocytes. Mechanistically, polyphenols were found to increase the intestinal nucleophilic tone of DQ8 mice by orchestrating an adaptive antioxidant response characterized by enhanced GSR enzyme activity and GSH content. Taken together, this work constitutes a highly relevant breakthrough as it provides the fundamental basis concerning the significance of natural polyphenols to be used in, for instance, the development of innovative functional foods aimed at CD individuals.


Assuntos
Biflavonoides/uso terapêutico , Catequina/uso terapêutico , Doença Celíaca/tratamento farmacológico , Enteropatias/tratamento farmacológico , Proantocianidinas/uso terapêutico , Sementes/química , Chá/química , Vitis/química , Animais , Antioxidantes/uso terapêutico , Biflavonoides/química , Catequina/química , Modelos Animais de Doenças , Gliadina/uso terapêutico , Mucosa Intestinal , Masculino , Camundongos , Camundongos Transgênicos , Proantocianidinas/química
20.
Eur J Immunol ; 39(12): 3552-61, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19795413

RESUMO

Celiac disease (CD) is an enteropathy triggered by gluten and mediated by CD4+ T cells. A complete understanding of CD immunopathogenesis has been hindered due to the lack of adequate in vivo models. Here, we explored the effect of the inhibition of COX by indomethacin in wheat gliadin-sensitized transgenic mice expressing the HLA-DQ8 heterodimer, a molecule associated with CD. Treated mice showed a gliadin-specific immune response with a significant reduction of villus height, not linked to crypt hyperplasia and to expansion of intraepithelial T cells. Notably, treated mice showed increased numbers of CD25+ and apoptotic cells in the lamina propria, whereas high basal levels of IFN-gamma secretion, along with a reduced gliadin-specific IL-2 expression were detected in MLN. Biochemical assessment of the lesion revealed increased mRNA of Lamb3 and Adamts2, encoding for ECM proteins, and enhanced activities of metalloproteinases MMP1, 2 and 7. We conclude that an intestinal sensitivity to gliadin, in connection with COX inhibition, caused a decreased villus height in DQ8 tg mice. The lesion was induced by a deregulated mucosal cell immunity to gliadin, thus triggering activation of a specific ECM protein pathway responsible for lamina propria remodeling.


Assuntos
Doença Celíaca/imunologia , Gliadina/imunologia , Antígenos HLA-DQ/imunologia , Mucosa Intestinal/imunologia , Proteínas ADAM/genética , Proteínas ADAMTS , Proteína ADAMTS4 , Animais , Apoptose , Complexo CD3/metabolismo , Doença Celíaca/genética , Doença Celíaca/metabolismo , Moléculas de Adesão Celular/genética , Inibidores de Ciclo-Oxigenase/farmacologia , Fatores de Transcrição Forkhead/metabolismo , Antígenos HLA-DQ/genética , Humanos , Imuno-Histoquímica , Indometacina/farmacologia , Interferon gama/metabolismo , Interleucina-2/metabolismo , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Metaloproteinase 13 da Matriz/metabolismo , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 7 da Matriz/metabolismo , Camundongos , Camundongos Transgênicos , Pró-Colágeno N-Endopeptidase/genética , Prostaglandina-Endoperóxido Sintases/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Linfócitos T/imunologia , Linfócitos T/metabolismo , Linfócitos T/patologia , Calinina
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