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1.
Nutr Res Pract ; 17(4): 616-630, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37529264

RESUMO

BACKGROUND/OBJECTIVES: Indole-3-propionic acid (IPA) is a tryptophan-derived microbial metabolite that has been associated with protective effects against inflammatory and metabolic diseases. However, there is a lack of knowledge regarding the effects of IPA under physiological conditions and at the intestinal level. MATERIALS/METHODS: Human intestinal epithelial Caco-2 cells were treated for 2, 24, and/or 72 h with IPA or its precursors - indole, tryptophan, and propionate - at 1, 10, 100, 250, or 500 µM to assess cell viability, integrity, differentiation, and proliferation. RESULTS: IPA induced cell proliferation and this effect was associated with a higher expression of extracellular signal-regulated kinase 2 (ERK2) and a lower expression of c-Jun. Although indole and propionate also induced cell proliferation, this involved ERK2 and c-Jun independent mechanisms. On the other hand, both tryptophan and propionate increased cell integrity and reduced the expression of claudin-1, whereas propionate decreased cell differentiation. CONCLUSIONS: In conclusion, these findings suggested that IPA and its precursors distinctly contribute to the proliferation, differentiation, and barrier function properties of human intestinal epithelial cells. Moreover, the pro-proliferative effect of IPA in intestinal epithelial cells was not explained by its precursors and is rather related to its whole chemical structure. Maintaining IPA at physiological levels, e.g., through IPA-producing commensal bacteria, may be important to preserve the integrity of the intestinal barrier and play an integral role in maintaining metabolic homeostasis.

2.
J Clin Med ; 12(5)2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36902512

RESUMO

BACKGROUND: Irritable bowel syndrome (IBS) is a prevalent gastrointestinal disease with no effective treatment. Altered microbiota composition seems implicated in disease etiology and therefore fecal microbial transplantation (FMT) has emerged as a possible treatment therapy. To clarify the clinical parameters impacting FMT efficacy, we conducted a systematic review with subgroup analysis. METHODS: A literature search was performed identifying randomized controlled trials (RCTs) comparing FMT with placebo in IBS adult patients (8-week follow-up) with a reported improvement in global IBS symptoms. RESULTS: Seven RCTs (489 participants) met the eligibility requirements. Although FMT seems not to be effective in global improvement of IBS symptoms, subgroup analysis shows that FMT through gastroscopy or nasojejunal tube are effective IBS treatments (RR 3.03; 95% CI 1.94-4.73; I2 = 10%, p < 0.00001). When considering non-oral ingestion routes, IBS patients with constipation symptoms are more likely to benefit from FMT administration (p = 0.003 for the difference between IBS subtypes regarding constipation). Fresh fecal transplant and bowel preparation seem also to have impact on FMT efficacy (p = 0.03 and p = 0.01, respectively). CONCLUSION: Our meta-analysis revealed a set of critical steps that could affect the efficacy of FMT as clinical procedure to treat IBS, nevertheless more RCTs are needed.

3.
Front Microbiol ; 12: 705020, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34349747

RESUMO

The risk factors for coronavirus disease 2019 (COVID-19) severity are still poorly understood. Considering the pivotal role of the gut microbiota on host immune and inflammatory functions, we investigated the association between changes in the gut microbiota composition and the clinical severity of COVID-19. We conducted a multicenter cross-sectional study prospectively enrolling 115 COVID-19 patients categorized according to: (1) the WHO Clinical Progression Scale-mild, 19 (16.5%); moderate, 37 (32.2%); or severe, 59 (51.3%), and (2) the location of recovery from COVID-19-ambulatory, 14 (household isolation, 12.2%); hospitalized in ward, 40 (34.8%); or hospitalized in the intensive care unit, 61 (53.0%). Gut microbiota analysis was performed through 16S rRNA gene sequencing, and the data obtained were further related to the clinical parameters of COVID-19 patients. The risk factors for COVID-19 severity were identified by univariate and multivariable logistic regression models. In comparison to mild COVID-19 patients, the gut microbiota of moderate and severe patients have: (a) lower Firmicutes/Bacteroidetes ratio; (b) higher abundance of Proteobacteria; and (c) lower abundance of beneficial butyrate-producing bacteria such as the genera Roseburia and Lachnospira. Multivariable regression analysis showed that the Shannon diversity index [odds ratio (OR) = 2.85, 95% CI = 1.09-7.41, p = 0.032) and C-reactive protein (OR = 3.45, 95% CI = 1.33-8.91, p = 0.011) are risk factors for severe COVID-19 (a score of 6 or higher in the WHO Clinical Progression Scale). In conclusion, our results demonstrated that hospitalized patients with moderate and severe COVID-19 have microbial signatures of gut dysbiosis; for the first time, the gut microbiota diversity is pointed out as a prognostic biomarker of COVID-19 severity.

4.
Biochimie ; 178: 124-136, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32949677

RESUMO

Although the jejunum is the main intestinal compartment responsible for lipid digestion and absorption, most of the studies assessing the impact of dietary lipids on the intestinal microbiota have been performed in the ileum, colon and faeces. This lack of interest in the jejunum is due to the much lower number of microbes present in this intestinal region and to the difficulty in accessing its lumen, which requires invasive methods. Recently, several recent publications highlighted that the whole jejunal microbiota or specific bacterial members are able to modulate lipid absorption and metabolism in enterocytes. This information reveals new strategies in the development of bacterial- and metabolite-based therapeutic interventions or nutraceutical recommendations to treat or prevent metabolic-related disorders, including obesity, cardiovascular diseases and malnutrition. This review is strictly focused on the following triad: dietary lipids, the jejunal epithelium and the jejunal microbiota. First, we will describe each member of the triad: the structure and functions of the jejunum, the composition of the jejunal microbiota, and dietary lipid handling by enterocytes and by microorganisms. Then, we will present the mechanisms leading to lipid malabsorption in small intestinal bacterial overgrowth (SIBO), a disease in which the jejunal microbiota is altered and which highlights the strong interactions among this triad. We will finally review the recent literature about the interactions among members of the triad, which should encourage research teams to further explore the mechanisms by which specific microbial strains or metabolites, alone or in concert, can mediate, control or modulate lipid absorption in the jejunum.


Assuntos
Gorduras na Dieta/metabolismo , Microbioma Gastrointestinal , Mucosa Intestinal/metabolismo , Mucosa Intestinal/fisiologia , Jejuno/metabolismo , Jejuno/microbiologia , Animais , Humanos , Absorção Intestinal/fisiologia , Enteropatias/complicações , Enteropatias/microbiologia , Jejuno/anatomia & histologia , Jejuno/fisiologia
5.
mBio ; 9(5)2018 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-30181250

RESUMO

The gut microbiota contributes to nutrients absorption and metabolism by enterocytes, but the molecular mechanisms involved remain poorly understood, and most conclusions are inferred from studies comparing germfree and conventional animals colonized with diverse bacterial species. We selected two model commensal microorganisms, Escherichia coli and Lactobacillus paracasei, to assess the role of the small-intestinal microbiota in modulating lipid absorption and metabolism by the epithelium. Using an integrated approach encompassing cellular and murine models and combining metabolic parameters measurement, lipid droplet imaging, and gene expression analysis, we demonstrated that under homeostatic conditions, L. paracasei promotes fat storage in enterocytes, whereas E. coli enhances lipid catabolism and reduces chylomicron circulating levels. The Akt/mammalian target of sirolimus (mTOR) pathway is inhibited by both bacterial species in vitro, indicating that several regulatory pathways are involved in the distinct intracellular lipid outcomes associated with each bacterial species. Moreover, soluble bacterial factors partially reproduce the effects observed with live microorganisms. However, reduction of chylomicron circulating levels in E. coli-colonized animals is lost under high-fat-diet conditions, whereas it is potentiated by L. paracasei colonization accompanied by resistance to hypercholesterolemia and excess body weight gain.IMPORTANCE The specific contribution of each bacterial species within a complex microbiota to the regulation of host lipid metabolism remains largely unknown. Using two model commensal microorganisms, L. paracasei and E. coli, we demonstrated that both bacterial species impacted host lipid metabolism in a diet-dependent manner and, notably, that L. paracasei-colonized mice but not E. coli-colonized mice resisted high-fat-diet-induced body weight gain. In addition, we set up cellular models of fatty acid absorption and secretion by enterocytes cocultured with bacteria and showed that, in vitro, both L. paracasei and E. coli inhibited lipid secretion, through increased intracellular fat storage and enhanced lipid catabolism, respectively.


Assuntos
Enterócitos/metabolismo , Escherichia coli/fisiologia , Interações entre Hospedeiro e Microrganismos , Lacticaseibacillus paracasei/fisiologia , Metabolismo dos Lipídeos , Animais , Quilomícrons/sangue , Dieta Hiperlipídica , Feminino , Microbioma Gastrointestinal , Lipídeos/biossíntese , Redes e Vias Metabólicas , Camundongos , Camundongos Endogâmicos C57BL , Simbiose , Serina-Treonina Quinases TOR/fisiologia , Aumento de Peso
6.
Inflamm Bowel Dis ; 24(3): 558-572, 2018 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-29462379

RESUMO

Gut microbiota has a fundamental role in the energy homeostasis of the host and is essential for proper "education" of the immune system. Intestinal microbial communities are able to ferment dietary fiber releasing short-chain fatty acids (SCFAs). The SCFAs, particularly butyrate (BT), regulate innate and adaptive immune cell generation, trafficing, and function. For example, BT has an anti-inflammatory effect by inhibiting the recruitment and proinflammatory activity of neutrophils, macrophages, dendritic cells, and effector T cells and by increasing the number and activity of regulatory T cells. Gut microbial dysbiosis, ie, a microbial community imbalance, has been suggested to play a role in the development of inflammatory bowel disease (IBD). The relationship between dysbiosis and IBD has been difficult to prove, especially in humans, and is probably complex and dynamic, rather than one of a simple cause and effect relationship. However, IBD patients have dysbiosis with reduced numbers of SCFAs-producing bacteria and reduced BT concentration that is linked to a marked increase in the number of proinflammatory immune cells in the gut mucosa of these patients. Thus, microbial dysbiosis and reduced BT concentration may be a factor in the emergence and severity of IBD. Understanding the relationship between microbial dysbiosis and reduced BT concentration to IBD may lead to novel therapeutic interventions.


Assuntos
Ácidos Graxos Voláteis/metabolismo , Microbioma Gastrointestinal , Imunidade nas Mucosas , Doenças Inflamatórias Intestinais/imunologia , Doenças Inflamatórias Intestinais/fisiopatologia , Mucosa Intestinal/imunologia , Animais , Butiratos , Disbiose/complicações , Ácidos Graxos Voláteis/uso terapêutico , Homeostase , Humanos , Doenças Inflamatórias Intestinais/microbiologia , Mucosa Intestinal/metabolismo , Intestinos/microbiologia , Receptores Acoplados a Proteínas G/metabolismo
7.
Biochimie ; 141: 97-106, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28571979

RESUMO

The modulation of the intestinal microbiota by high-fat diet (HFD) has a major impact on both immunological and metabolic functions of the host. Taking this into consideration, the aim of this contribution is to review the impact of HFD on microbiota profile and small intestinal physiology before and after the onset of obesity and its metabolic complications. Evidence from animal studies suggest that before the onset of obesity and its metabolic complications, HFD induces intestinal dysbiosis - encompassing changes in composition balance and massive redistribution with bacteria occupying intervillous spaces and crypts - associated with early physiopathological changes, predominantly in the ileum, such as low-grade inflammation, decreased antimicrobial peptides expression, impaired mucus production, secretion and layer's thickness, and decreased expression of tight junction proteins. With time, major inflammatory signals (e.g. toll-like receptor-4 dependent) become activated, thereby stimulating proinflammatory cytokines secretion in the small intestine. This inflammatory state might subsequently exacerbate disruption of the mucus layer barrier and increase epithelial permeability of the small intestine, thereby creating an environment that facilitates the passage of bacterial components (e.g. lipopolysaccharide, peptidoglycan and flagellin) and metabolites from the intestinal lumen (e.g. secondary bile acids) to the circulation and peripheral tissues (i.e. leaky gut), eventually promoting the development of systemic inflammation, obesity, adiposity, insulin resistance and glucose intolerance preceding hyperglycemia. Although the mechanisms are still not completely understood, prebiotics, probiotics, polyphenols, peroxisome proliferator-activated receptor-γ agonists (such as rosiglitazone) and exercise have been shown to reverse HFD-induced intestinal phenotype and to attenuate the severity of obesity and its associated metabolic complications.


Assuntos
Gorduras na Dieta/efeitos adversos , Microbioma Gastrointestinal/imunologia , Intestino Delgado/microbiologia , Obesidade/microbiologia , Animais , Gorduras na Dieta/imunologia , Humanos , Intestino Delgado/imunologia , Obesidade/imunologia , Receptor 4 Toll-Like/imunologia
8.
Ageing Res Rev ; 22: 9-19, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25939915

RESUMO

In almost all tissues, including the brain, folates are required for one-carbon transfer reactions, which are essential for the synthesis of DNA and RNA nucleotides, the metabolism of amino acids and the occurrence of methylation reactions. The aim of this paper is to review the impact of folate status on the risk of development of neuropsychiatric disorders in older individuals. The prevalence of folate deficiency is high among individuals aged ≥ 65 years mainly due to reduced dietary intake and intestinal malabsorption. Population-based studies have demonstrated that a low folate status is associated with mild cognitive impairment, dementia (particularly Alzheimer's disease) and depression in healthy and neuropsychiatric diseased older individuals. The proposed mechanisms underlying that association include hyperhomocysteinemia, lower methylation reactions and tetrahydrobiopterin levels, and excessive misincorporation of uracil into DNA. However, currently, there is no consistent evidence demonstrating that folic acid supplementation improves cognitive function or slows cognitive decline in healthy or cognitively impaired older individuals. In conclusion, folate deficiency seems to be an important contributor for the onset and progression of neuropsychiatric diseases in the geriatric population but additional studies are needed in order to increase the knowledge of this promising, but still largely unexplored, area of research.


Assuntos
Envelhecimento , Disfunção Cognitiva , Demência , Depressão , Deficiência de Ácido Fólico/complicações , Ácido Fólico , Idoso , Envelhecimento/fisiologia , Envelhecimento/psicologia , Encéfalo/metabolismo , Cognição/efeitos dos fármacos , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/prevenção & controle , Demência/etiologia , Demência/metabolismo , Demência/prevenção & controle , Depressão/etiologia , Depressão/metabolismo , Progressão da Doença , Ácido Fólico/metabolismo , Ácido Fólico/farmacologia , Deficiência de Ácido Fólico/metabolismo , Humanos , Absorção Intestinal , Complexo Vitamínico B/metabolismo , Complexo Vitamínico B/farmacologia
9.
J Nutr Biochem ; 26(5): 563-70, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25727966

RESUMO

Catecholamines (CA) play an important role in cardiovascular (CDV) disease risk. Namely, noradrenaline (NA) levels positively correlate whereas adrenaline (AD) levels negatively correlate with obesity and/or CDV disease. Western diets, which are tipically rich in Ω-6 fatty acids (FAs) and deficient in Ω-3 FAs, may contribute to the development of obesity, type 2 diabetes and/or coronary artery disease. Taking this into consideration and the fact that our group has already described that saturated FAs affect catecholamine handling by adrenal chromaffin cells, this work aimed to investigate the effect of unsaturated FAs upon catecholamine handling in the same model. Our results showed that chronic exposure to unsaturated FAs differently modulated CA cellular content and release, regardless of both FA series and number of carbon atoms. Namely, the Ω-6 arachidonic and linoleic acids, based on their effect on CA release and cellular content, seemed to impair NA and AD vesicular transport, whereas γ-linolenic acid selectively impaired AD synthesis and release. Within the Ω-9 FAs, oleic acid was devoid of effect, and elaidic acid behaved similarly to γ-linolenic acid. Eicosapentaenoic and docosahexaenoic acids (Ω-3 series) impaired the synthesis and release of both NA and AD. These results deserve attention and future development, namely, in what concerns the mechanisms involved and correlative effects in vivo.


Assuntos
Catecolaminas/metabolismo , Células Cromafins/efeitos dos fármacos , Gorduras na Dieta/farmacologia , Ácidos Graxos Insaturados/farmacologia , Animais , Bovinos , Células Cromafins/metabolismo
10.
Curr Diab Rep ; 15(2): 569, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25620402

RESUMO

Gestational diabetes mellitus (GDM) is a metabolic disorder prevalent among pregnant women. This disease increases the risk of adverse perinatal outcomes and diseases in the offspring later in life. The human placenta, the main interface between the maternal and fetal blood circulations, is responsible for the maternal-to-fetal transfer of nutrients essential for fetal growth and development. In this context, the aim of this article is to review the latest advances in the placental transport of macro and micronutrients and how they are affected by GDM and its associated conditions, such as elevated levels of glucose, insulin, leptin, inflammation, and oxidative stress. Data analyzed in this article suggest that GDM and its associated conditions, particularly high levels of glucose, leptin, and oxidative stress, disturb placental nutrient transport and, consequently, fetal nutrient supply. As a consequence, this disturbance may contribute to the fetal and postnatal adverse health outcomes associated with GDM.


Assuntos
Aminoácidos/metabolismo , Diabetes Gestacional/etiologia , Glucose/metabolismo , Troca Materno-Fetal/fisiologia , Micronutrientes/metabolismo , Circulação Placentária/fisiologia , Diabetes Gestacional/metabolismo , Feminino , Humanos , Estresse Oxidativo , Gravidez
11.
Eur Neuropsychopharmacol ; 25(1): 1-16, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25523882

RESUMO

The use of antipsychotic drugs for the treatment of mood disorders and psychosis has increased dramatically over the last decade. Despite its consumption being associated with beneficial neuropsychiatric effects in patients, atypical antipsychotics (which are the most frequently prescribed antipsychotics) use is accompanied by some secondary adverse metabolic effects such as weight gain, dyslipidemia and glucose intolerance. The molecular mechanisms underlying these adverse effects are not fully understood but have been suggested to involve a dysregulation of adipose tissue homeostasis. As such, the aim of this paper is to review and discuss the role of adipose tissue in the development of secondary adverse metabolic effects induced by atypical antipsychotics. Data analyzed in this article suggest that atypical antipsychotics may increase adipose tissue (particularly visceral adipose tissue) lipogenesis, differentiation/hyperplasia, pro-inflammatory mediator secretion and insulin resistance and decrease adipose tissue lipolysis. Consequently, patients receiving antipsychotic medication could be at risk of developing obesity, type 2 diabetes and cardiovascular disease. A better knowledge of the impact of these drugs on adipose tissue homeostasis may unveil strategies to develop novel antipsychotic drugs with less adverse metabolic effects and to develop adjuvant therapies (e.g. behavioral and nutritional therapies) to neuropsychiatric patients receiving antipsychotic medication.


Assuntos
Tecido Adiposo/patologia , Antipsicóticos/efeitos adversos , Resistência à Insulina/fisiologia , Doenças Metabólicas/induzido quimicamente , Animais , Homeostase/efeitos dos fármacos , Humanos , Aumento de Peso/efeitos dos fármacos
12.
Reprod Toxicol ; 49: 196-201, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25263228

RESUMO

The nutritional environment during embryonic, fetal and neonatal development plays a crucial role in the offspring's risk of developing diseases later in life. Although non-nutritive sweeteners (NNS) provide sweet taste without contributing to energy intake, animal studies showed that long-term consumption of NSS, particularly aspartame, starting during the perigestational period may predispose the offspring to develop obesity and metabolic syndrome later in life. In this paper, we review the impact of NNS exposure during the perigestational period on the long-term disease risk of the offspring, with a particular focus on metabolic diseases. Some mechanisms underlying NNS adverse metabolic effects have been proposed, such as an increase in intestinal glucose absorption, alterations in intestinal microbiota, induction of oxidative stress and a dysregulation of appetite and reward responses. The data reviewed herein suggest that NNS consumption by pregnant and lactating women should be looked with particular caution and requires further research.


Assuntos
Lactação/efeitos dos fármacos , Doenças Metabólicas/induzido quimicamente , Adoçantes não Calóricos/efeitos adversos , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Aspartame/efeitos adversos , Feminino , Humanos , Masculino , Gravidez/efeitos dos fármacos
13.
Int J Endocrinol ; 2014: 384583, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24672546

RESUMO

The Metabolic Syndrome increases the risk for atherosclerotic cardiovascular disease and type 2 Diabetes Mellitus. Increased fructose consumption and/or mineral deficiency have been associated with Metabolic Syndrome development. This study aimed to investigate the effects of 8 weeks consumption of a hypersaline sodium-rich naturally sparkling mineral water on 10% fructose-fed Sprague-Dawley rats (Metabolic Syndrome animal model). The ingestion of the mineral water (rich in sodium bicarbonate and with higher potassium, calcium, and magnesium content than the tap water used as control) reduced/prevented not only the fructose-induced increase of heart rate, plasma triacylglycerols, insulin and leptin levels, hepatic catalase activity, and organ weight to body weight ratios (for liver and both kidneys) but also the decrease of hepatic glutathione peroxidase activity and oxidized glutathione content. This mineral-rich water seems to have potential to prevent Metabolic Syndrome induction by fructose. We hypothesize that its regular intake in the context of modern diets, which have a general acidic character interfering with mineral homeostasis and are poor in micronutrients, namely potassium, calcium, and magnesium, could add surplus value and attenuate imbalances, thus contributing to metabolic and redox health and, consequently, decreasing the risk for atherosclerotic cardiovascular disease.

14.
Magnes Res ; 27(3): 131-41, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25560240

RESUMO

Catechol-O-methyltransferase (COMT) is a magnesium-dependent, catecholamine-metabolizing enzyme, whose impaired activity has been positively associated with cardiovascular diseases, particularly hypertension. Consumption of some natural mineral-rich waters has been shown to exert protective effects on cardiovascular risk factors, eg. by decreasing arterial blood pressure and blood lipids. However, the molecular mechanisms underlying these effects are still poorly understood. So, the aim of this work was to investigate the effect of natural mineral-rich water ingestion upon liver and adrenal glands COMT expression and activity in Wistar Han rats. Over a seven-week period, animals had access to one of the following three drinking solutions: 1) tap water (control group; TW), 2) tap water with added Na(+) (to make the same concentration as in the MW group (TWNaCl group), or 3) natural mineral-rich water [Pedras Salgadas(®), which is very rich in bicarbonate, and with higher sodium, calcium and magnesium content than control tap water (MW group)]. COMT expression and activity were determined by RT-PCR and HPLC-ED, respectively. A higher hepatic COMT activity was found in the MW group compared with the TW and TWNaCl groups. On the other hand, adrenal gland COMT mRNA expression decreased in the MW group compared to TW group. In conclusion, the ability of natural mineral-rich waters to increase hepatic COMT activity may eventually explain the positive cardiovascular effects associated with the consumption of some natural mineral-rich waters.


Assuntos
Glândulas Suprarrenais/enzimologia , Catecol O-Metiltransferase/análise , Fígado/enzimologia , Águas Minerais , Cloreto de Sódio/farmacologia , Água/farmacologia , Ácido 3,4-Di-Hidroxifenilacético/metabolismo , Glândulas Suprarrenais/efeitos dos fármacos , Animais , Doenças Cardiovasculares/prevenção & controle , Catecol O-Metiltransferase/biossíntese , Catecol O-Metiltransferase/genética , Catecolaminas/sangue , Cromatografia Líquida de Alta Pressão , Ingestão de Líquidos , Indução Enzimática/efeitos dos fármacos , Epinefrina/metabolismo , Fígado/efeitos dos fármacos , Masculino , Águas Minerais/análise , Neoplasias/prevenção & controle , Ratos , Ratos Wistar
15.
Reprod Toxicol ; 40: 76-81, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23806338

RESUMO

Increased oxidative stress (OS) is implicated in the pathophysiology of several pregnancy disorders. We aimed to investigate the effect of tert-butylhydroperoxide (TBHP)-induced OS upon the placental transport of the neutral amino acids L-methionine (L-Met) and L-alanine (L-Ala), by using a human trophoblast cell model (BeWo cells). TBHP reduced both total and Na(+)-independent (14)C-L-Met intracellular steady-state accumulation over time (Amax), by reducing non-system L-mediated uptake - most probably system y(+) - while having no effect on system L. Moreover, TBHP reduced total (14)C-L-Ala Amax through an inhibition of system A. The effect of TBHP upon total, but not system A-mediated, (14)C-L-Ala uptake was dependent upon phosphoinositide 3-kinase (PI3K) and protein kinase C (PKC) activation, and was completely prevented by the polyphenol quercetin. In conclusion, a reduction in placental uptake of neutral amino acids may contribute to the deleterious effects of pregnancy disorders associated with OS.


Assuntos
Alanina/metabolismo , Aminoácidos Neutros/metabolismo , Placenta/metabolismo , terc-Butil Hidroperóxido/toxicidade , Linhagem Celular , Feminino , Humanos , Estresse Oxidativo , Fosfatidilinositol 3-Quinases/metabolismo , Placenta/citologia , Gravidez , Proteína Quinase C/metabolismo , Quercetina/farmacologia
16.
Ciênc. rural ; 43(2): 338-341, Feb. 2013. ilus, tab
Artigo em Inglês | LILACS | ID: lil-665880

RESUMO

We report exogenous pigmentation in sheep grazing in native pastures in northeastern Brazil. The sheep carcasses from a farm were condemned at the slaughterhouse due to pigmentation of the carcasses and viscera. In visits to the farm, bluish-purple pigmentation of the mucosa was observed in the sheep. In two necropsied sheep, a bluish-purple pigment was observed in the skin, subcutaneous tissue, fat, muscles, cartilage, bones, serous membranes of the forestomachs, kidneys, adrenal glands, and the mucosa of the uterus, urinary bladder, urethra, vagina, trachea, bronchi, and bronchioles. Some bone surfaces, the intima of large arteries, tendons, muscle insertions, and ligaments had a yellow-brown or light brown pigment. However, the pigment was not observed upon histologic examination of tissues, suggesting that the pigmentation is caused by a plant. Two plants, Rhamnidium molle and Pereskia bahiensis, were fed to experimental sheep and rabbits, but did not cause pigmentation.


Descreve-se pigmentação exógena em ovinos, pastejando numa área de pastagem nativa da região nordeste do Brasil. Os ovinos de uma fazenda, destinados ao abate, tiveram as carcaças rejeitadas pelo frigorífico em virtude da pigmentação apresentada nos tecidos. Em visitas à fazenda, foi observada pigmentação azul-violeta nas mucosas de ovelhas. Em dois ovinos necropsiados, pigmento azul-violeta foi observado na pele, tecido subcutâneo, gordura, músculos, cartilagens, ossos, serosa dos pré-estômagos, rins, glândulas adrenais, mucosa do útero, bexiga urinária, uretra, vagina, traqueia, brônquios e bronquíolos. Algumas superfícies ósseas, íntima de grandes artérias, tendões, inserções musculares e ligamentos tinham pigmento castanho-amarelo ou castanho claro. No entanto, o pigmento não foi observado nos tecidos após processamento para o exame histológico, o que sugere que a pigmentação é causada por uma substância exógena, provavelmente presente em uma planta consumida. Duas plantas, Rhamnidium molle e Pereskia bahiensis, foram fornecidas experimentalmente a ovinos e coelhos, mas não causaram pigmentação.

17.
Naunyn Schmiedebergs Arch Pharmacol ; 379(4): 325-36, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19023563

RESUMO

The aim of this study was to investigate the putative influence of some pharmacological agents and drugs of abuse upon the apical uptake of butyrate (BT) into Caco-2 cells. The apical uptake of (14)C-BT by Caco-2 cells was (1) time and concentration dependent, (2) pH dependent, (3) Na(+) independent and Cl(-) dependent, (4) energy dependent, (5) inhibited by several BT structural analogues (acetate, propionate, alpha-ketobutyrate, pyruvate, lactate), (6) insensitive to the anion exchange inhibitors DIDS and SITS and (7) inhibited by the monocarboxylate transport (MCT) inhibitors NPPB and pCMB. These characteristics are compatible with an involvement of MCT1-mediated transport. Acutely, uptake of a low concentration of (14)C-BT (10 microM) was reduced by acetaldehyde, acetylsalicylic acid, indomethacin, caffeine and theophylline and increased by MDMA. Chronically, uptake was increased by caffeine and decreased by tetrahydrocannabinol and MDMA; reverse transcription quantitative real-time PCR analysis showed that these three compounds decreased the mRNA levels of MCT1. Acutely, acetaldehyde, indomethacin and MDMA reduced the uptake of a high concentration of (14)C-BT (20 mM), and acetylsalicylic acid increased it. Chronically, none of the compounds affected uptake. Acetaldehyde, indomethacin and propionate seem to be competitive inhibitors of (14)C-BT uptake. Acetylsalicylic acid simultaneously increased the K (m) and the V (max) of (14)C-BT uptake. In conclusion, MCT1-mediated transport of (14)C-BT in Caco-2 cells is modulated by either acute or chronic exposure to some pharmacological agents and drugs of abuse (acetaldehyde, acetylsalicylic acid, indomethacin, caffeine, theophylline and the drugs of abuse tetrahydrocannabinol and MDMA).


Assuntos
Butiratos/metabolismo , 2,4-Dinitrofenol/farmacologia , Ácido 4,4'-Di-Isotiocianoestilbeno-2,2'-Dissulfônico/farmacologia , Ácido 4-Acetamido-4'-isotiocianatostilbeno-2,2'-dissulfônico/farmacologia , Acetaldeído/farmacologia , Ácidos Acíclicos/farmacologia , Aspirina/farmacologia , Transporte Biológico Ativo/efeitos dos fármacos , Células CACO-2 , Cafeína/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Dronabinol/farmacologia , Expressão Gênica/efeitos dos fármacos , Expressão Gênica/genética , Humanos , Concentração de Íons de Hidrogênio , Indometacina/farmacologia , Íons/farmacologia , Cinética , Transportadores de Ácidos Monocarboxílicos/antagonistas & inibidores , Transportadores de Ácidos Monocarboxílicos/genética , N-Metil-3,4-Metilenodioxianfetamina/farmacologia , Azida Sódica/farmacologia , Simportadores/antagonistas & inibidores , Simportadores/genética , Teofilina/farmacologia
18.
Pharmacology ; 82(1): 30-7, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18431074

RESUMO

The endogenous cannabinoid system plays a role in the regulation of energy homeostasis acting through central pathways, and its dysregulation may be implicated in the pathogenesis of obesity. Recent evidence is accumulating showing that the endogenous cannabinoid system is also present in peripheral tissues. The aim of this work was to investigate the effect of cannabinoids upon the intestinal absorption of glucose. For this, we investigated the effect of some cannabinoid receptor agonists and antagonists upon the apical uptake of 3H-2-deoxy-D-glucose by the human intestinal epithelial Caco-2 cells. Uptake of a low concentration of 3H-2-deoxy-D-glucose (1 micromol/l) was both cytochalasin B- and phloridzin-sensitive. The maximal inhibition obtained with each of these inhibitors was 50%, and their effect was not cumulative. On the other hand, uptake of a high concentration of 3H-2-deoxy-D-glucose (20 mmol/l) was partially inhibited by cytochalasin B (+/-20%) and phloridzin had no effect. We verified that neither the cannabinoid receptor agonists [tetrahydrocannabinol (1-10 micromol/l), anandamide (0.1-10 micromol/l) and CP 55,940 (5 nmol/l to 1 micromol/l)], nor the specific CB1 and CB2 antagonists [AM251 (10-500 nmol/l) and AM630 (50 nmol/l to 1 micromol/l), respectively] had a significant effect upon 3H-2-deoxy-D-glucose uptake by Caco-2 cells. This was true for both the uptake of a low (1 micromol/l) and of a high (20 mmol/l) concentration of 3H-2-deoxy-D-glucose. From these results, we may hypothesize that cannabinoids do not interfere with the intestinal GLUT2-mediated apical uptake of glucose.


Assuntos
Agonistas de Receptores de Canabinoides , Antagonistas de Receptores de Canabinoides , Canabinoides/farmacologia , Desoxiglucose/metabolismo , Absorção Intestinal , Ácidos Araquidônicos/farmacologia , Células CACO-2 , Canabinoides/metabolismo , Cicloexanóis/farmacologia , Dronabinol/farmacologia , Endocanabinoides , Humanos , Indóis/farmacologia , Piperidinas/farmacologia , Alcamidas Poli-Insaturadas/farmacologia , Pirazóis/farmacologia
19.
Pesqui. bras. odontopediatria clín. integr ; 6(1): 65-70, jan.-abr. 2006. tab
Artigo em Português | LILACS, BBO - Odontologia | ID: lil-437405

RESUMO

Objetivo: Verificar a ocorrência de maus tratos na infância eadolescência (0 a 18 anos) registrados no Conselho Tutelar domunicípio de Caruaru/PE no período de 2002 a 2004. Método:Para isso, foi solicitado ao Conselho Tutelar dados referentesaos registros de denúncias no período citado. Resultados: Aocorrência de maus tratos foi de 798 casos e o tipo maisdetectado foi a negligência (49,24 porcento), seguida da violênciapsicológica (28,94 porcento). A violência física e a violência sexualalcançaram percentuais de 17,6 porcento e 4,66 porcento, respectivamente.De uma maneira geral, o sexo masculino foi o que apresentou omaior percentual de registros (55,3porcento). Conclusão:De acordocom a literatura consultada a localização mais freqüente daslesões é a área orofacial evidenciando-se a responsabilidadeética e legal do cirurgião-dentista neste contexto e, pelos dadosapresentados, há a necessidade emergente de criarmecanismos de proteção a criança e ao adolescente, comotambém da realização de campanhas educativas preventivasenfocando a necessidade de denúncia e prevenção de todo equalquer tipo de maus tratos.


Assuntos
Humanos , Masculino , Feminino , Criança , Adolescente , Maus-Tratos Infantis/psicologia , Abuso Sexual na Infância/psicologia , Violência Doméstica/psicologia , Ética Odontológica/educação
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