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2.
Nutr Metab Cardiovasc Dis ; 31(12): 3407-3414, 2021 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-34663538

RESUMO

BACKGROUND AND AIMS: Information regarding inflammation and cardiovascular disease (CVD) risk in type 1 diabetes (T1D) or preeclampsia (PE) is scarce. We assessed differences in inflammation markers according to the presence of both conditions and their association with atherosclerosis. METHODS AND RESULTS: We recruited 112 women without CVD and last pregnancy ≥5 years previously (n = 28 per group): a)T1D and PE; b)T1D without PE; c)PE without T1D; and d)Controls (without T1D or PE). Groups were matched by several CVD risk factors, and diabetes duration and retinopathy in T1D. Carotid intima-media thickness (IMT) and plaque presence (IMT ≥1.5 mm) were assessed by ultrasonography. Inflammatory markers included classical variables (leucocytes and high-sensitivity C-reactive protein [hsCRP]) and glycoproteins by nuclear magnetic resonance (1H-NMR) spectroscopy (GlycA, GlycB, GlycF and the height/width [H/W] ratios of GlycA and GlycB). The age of the participants was 44.9 ± 7.8 years, and 20.5% harbored plaque. There were no differences in inflammatory markers among the four study groups. Overall, in multivariate-adjusted models, all 1H-NMR-glycoproteins (except GlycB) were positively associated with IMT measures (IMT of bulb and maximum-IMT of any carotid segment; p < 0.05). After dividing the sample according to PE status, previous findings remained largely unchanged. Furthermore, GlycF was independently associated with carotid plaque only in PE group (OR 5.08 [1.03-25.01] per 0.1 log-increments, p = 0.046). Neither leucocytes nor hsCRP were related to atherosclerosis. Regarding T1D status, non-uniform results were observed. CONCLUSIONS: High 1H-NMR-glycoprotein concentrations have a negative impact on carotid atherosclerosis among women with preeclampsia, regardless of T1D status.


Assuntos
Aterosclerose , Glicoproteínas , Pré-Eclâmpsia , Adulto , Aterosclerose/sangue , Aterosclerose/diagnóstico , Biomarcadores/sangue , Diabetes Mellitus Tipo 1/epidemiologia , Feminino , Glicoproteínas/sangue , Humanos , Pessoa de Meia-Idade , Pré-Eclâmpsia/epidemiologia , Gravidez
3.
J Neurochem ; 156(2): 182-199, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32936929

RESUMO

In the adult hypothalamus, the neuronal precursor role is attributed to the radial glia-like cells that line the third-ventricle (3V) wall called tanycytes. Under nutritional cues, including hypercaloric diets, tanycytes proliferate and differentiate into mature neurons that moderate body weight, suggesting that hypothalamic neurogenesis is an adaptive mechanism in response to metabolic changes. Previous studies have shown that the tanycyte glucosensing mechanism depends on connexin-43 hemichannels (Cx43 HCs), purine release, and increased intracellular free calcium ion concentration [(Ca2+ )i ] mediated by purinergic P2Y receptors. Since, Fibroblast Growth Factor 2 (FGF2) causes similar purinergic events in other cell types, we hypothesize that this pathway can be also activated by FGF2 in tanycytes to promote their proliferation. Here, we used bromodeoxyuridine (BrdU) incorporation to evaluate if FGF2-induced tanycyte cell division is sensitive to Cx43 HC inhibition in vitro and in vivo. Immunocytochemical analyses showed that cultured tanycytes maintain the expression of in situ markers. After FGF2 exposure, tanycytic Cx43 HCs opened, enabling release of ATP to the extracellular milieu. Moreover, application of external ATP was enough to induce their cell division, which could be suppressed by Cx43 HC or P2Y1-receptor inhibitors. Similarly, in vivo experiments performed on rats by continuous infusion of FGF2 and a Cx43 HC inhibitor into the 3V, demonstrated that FGF2-induced ß-tanycyte proliferation is sensitive to Cx43 HC blockade. Thus, FGF2 induced Cx43 HC opening, triggered purinergic signaling, and increased ß-tanycytes proliferation, highlighting some of the molecular mechanisms involved in the cell division response of tanycyte. This article has an Editorial Highlight see https://doi.org/10.1111/jnc.15218.


Assuntos
Conexina 43/metabolismo , Células Ependimogliais/fisiologia , Fator 2 de Crescimento de Fibroblastos/metabolismo , Canais Iônicos/metabolismo , Neurogênese/fisiologia , Animais , Proliferação de Células/fisiologia , Masculino , Células-Tronco Neurais/fisiologia , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/fisiologia
4.
Diabetes Metab Res Rev ; 37(1): e3362, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32515046

RESUMO

AIMS: Persistence of lipoprotein abnormalities in type 1 diabetes (T1D) and/or pre-eclampsia could be associated with cardiovascular disease (CVD). We assessed differences in the advanced lipoprotein profiles according to the presence of both conditions and their differential association with atherosclerosis. MATERIAL AND METHODS: We recruited 112 women without CVD and last pregnancy ≥5 years previously, divided into four groups (n = 28 per group): (a) T1D and previous pre-eclampsia; (b) T1D without pre-eclampsia; (c) pre-eclampsia without T1D; and (d) controls (without T1D/pre-eclampsia). Groups were matched by several risk factors, and diabetes duration and retinopathy in T1D. Carotid intima-media thickness (IMT) and the presence of plaque (IMT ≥1.5 mm) were assessed by ultrasonography. The lipoprotein profile was evaluated by nuclear magnetic resonance (NMR) spectroscopy. RESULTS: The participants were 44.9 ± 7.8 years old. Carotid plaque presence was 20.5%, with a higher prevalence in T1D and/or pre-eclampsia vs controls (P < .05). High-density lipoprotein (HDL)-related variables differed among groups, mainly driven by an increase in T1D (P < .05), whereas triglyceride-related variables were increased in pre-eclampsia [medium very low-density lipoprotein (VLDL) particles and triglyceride enrichment in HDL and low-density lipoprotein (LDL)]. Overall, in multivariate-adjusted models, LDL-related variables were the most strongly associated with atherosclerosis (P < .05). In age- and statin-adjusted models, previous pre-eclampsia showed an independent association with triglyceride-related variables (plaque: medium-VLDL-particles, OR 1.550 [1.013-2.374]; HDL-cholesterol/HDL-triglycerides ratio, OR 0.411 [0.175-0.967]). Regarding T1D, HDL-parameters were also differentially associated (maximum-IMT: HDL-cholesterol/HDL-particles ratio, ß = -.258, P = .036). CONCLUSIONS: NMR lipoproteins were differentially and independently associated with atherosclerosis in T1D/pre-eclampsia. Further studies are needed to ascertain the role of NMR parameters as CVD biomarkers in this high-risk population.


Assuntos
Doenças das Artérias Carótidas , Diabetes Mellitus Tipo 1 , Lipoproteínas , Pré-Eclâmpsia , Adulto , Biomarcadores/sangue , Doenças das Artérias Carótidas/sangue , Doenças das Artérias Carótidas/epidemiologia , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/epidemiologia , Feminino , Humanos , Lipoproteínas/sangue , Pessoa de Meia-Idade , Ressonância Magnética Nuclear Biomolecular , Pré-Eclâmpsia/sangue , Pré-Eclâmpsia/epidemiologia , Gravidez
5.
J Tissue Eng Regen Med ; 15(2): 129-138, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33197151

RESUMO

3D Printing has become a mainstay of industry, with several applications in the medical field. One area that could benefit from 3D printing is intestinal failure due to injury or genetic malformations. We bioprinted cylindrical tubes from rat vascular cells that were sized to form biopatches. 2 mm enterotomies were made in the small intestine of male Sprague-Dawley rats, and sealed with biopatches. These intestinal segments were connected to an ex vivo perfusion device that provided independent extraluminal and intraluminal perfusion. The fluorescence signal of fluorescein isothiocyanate (FITC)-inulin in the intraluminal perfusate, a non-absorbable fluorescent marker of intestinal integrity, was measured every 15 min over 90 min, and used to assess the integrity of the segments under both continuous perfusion and alternate-flow perfusion. Enterotomies were made an inch away from the ileocecal junction in male Wistar rats and sealed with biopatches. The animals were monitored daily and euthanized at post-operative days 7, 14, 21, and 30. Blinded histopathological analysis was conducted to compare the patch segments to native intestine. Biopatch-sealed intestinal segments withstood both continuous and pulsatile flow rates without leakage of FITC-inulin above the control baseline. 21 of 26 animals survived with normal activity, weight gain, and stool output. Histopathology of the explanted segments showed progressive villi and crypt formation over the enterotomies, with complete restoration of the epithelium by 30 days. This study presents a novel application of 3D bioprinting to develop a universal repair patch that can seal lesions in vivo, and fully integrate into the native intestine.


Assuntos
Bioimpressão , Hidrogéis , Mucosa Intestinal , Intestino Delgado , Impressão Tridimensional , Animais , Hidrogéis/química , Hidrogéis/farmacologia , Mucosa Intestinal/lesões , Mucosa Intestinal/metabolismo , Mucosa Intestinal/cirurgia , Intestino Delgado/lesões , Intestino Delgado/metabolismo , Intestino Delgado/cirurgia , Masculino , Ratos , Ratos Wistar
6.
Diabetes Res Clin Pract ; 171: 108548, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33238177

RESUMO

AIMS: Evaluate the role of plasma metabolomics in atherosclerosis according to the presence of type 1 diabetes (T1D) or previous preeclampsia. METHODS: We recruited 105 women without cardiovascular disease and last pregnancy ≥5 years previously, divided according to the presence of T1D or previous preeclampsia. Preclinical atherosclerosis was defined as the presence of carotid plaque (intima-media thickness ≥1.5 mm) assessed by ultrasonography. Metabolomics were evaluated by nuclear magnetic resonance (NMR). Bivariate and multivariate-adjusted differences in NMR-metabolomics were evaluated. RESULTS: The participants were 44.9 ± 8.1 years-old; 20% harbored plaques. There were significant differences in lipidic-, energetic- and nitrogen-related metabolites according to the presence of T1D/preeclampsia (p < 0.05). In multivariate-adjusted models (by age, statins, blood pressure and T1D/preeclampsia), only lipidomic-related metabolites were associated with atherosclerosis in the whole sample. However, stronger associations were observed in women with previous preeclampsia (vs. without; per 0.5 mmol/L increments); phosphatidylcholine, OR 4.08 (1.32-27.22); free cholesterol, 5.18 (1.22-21.97); saturated fatty acids, OR 2.99 (1.37-6.48); w-7, OR 2.29 (1.15-4.56); and w-9 fatty acids, OR 1.49 (1.00-2.23). CONCLUSIONS: NMR-metabolomics showed a differential pattern according to the presence of T1D/preeclampsia in relation to preclinical atherosclerosis. Since most of these metabolites mirror lifestyle factors, they could help tailor dietetic advice in high-risk women.


Assuntos
Aterosclerose/diagnóstico , Diabetes Mellitus Tipo 1/complicações , Espectroscopia de Ressonância Magnética/métodos , Metabolômica/métodos , Placa Aterosclerótica/diagnóstico , Pré-Eclâmpsia/diagnóstico , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Placa Aterosclerótica/diagnóstico por imagem , Gravidez , Fatores de Risco
7.
Front Behav Neurosci ; 14: 591204, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33335480

RESUMO

Stereotactic surgery is a widely used procedure in neuroscience research to study the brain's regulation of feeding behavior. In line with this notion, this study aims to assess how food consumption and feeding patterns are affected in response to the use of auditory bars that preserve or damage the tympanic membrane during stereotactic surgery. Our previous observations led us to hypothesize that the traumatic tympanic membrane rupture affects food intake and feeding patterns in rats undergoing stereotactic procedures. Thereby, female and male rats were cannulated in the third ventricle (3V) using both types of auditory bars. Post-surgical pain was assessed using the grimace scale. Food intake, meal patterns and weight gain or loss were analyzed for 5-7 consecutive days after surgery. Normal food intake, increased body weight and regular meal patterns were observed from postoperative day 2 when the stereotactic procedure was performed using auditory bars that maintain the integrity of the tympanic membrane. However, tympanic membrane rupture prevented the expected recovery of food intake and body weight. This effect was accompanied by an alteration in eating patterns, which was persistent over 7 days of recovery. Thus, tympanic membrane preservation during surgery is necessary to evaluate short-term feeding patterns. This study demonstrates auditory bars that do not damage the tympanic membrane should be used when performing stereotactic surgery for subsequent analysis of rat behavior.

8.
Cell Physiol Biochem ; 54(6): 1132-1142, 2020 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-33175479

RESUMO

BACKGROUND/AIMS: The colonic H+, K+ ATPase (HKA2) is a heterodimeric membrane protein that exchanges luminal K+ for intracellular H+ and is involved in maintaining potassium homeostasis. Under homeostatic conditions, the colonic HKA2 remains inactive, since most of the potassium is absorbed by the small intestine. In diarrheal states, potassium is secreted and compensatory potassium absorption becomes necessary. This study proposes a novel mechanism whereby the addition of penicillin G sodium salt (penG) to colonic crypts stimulates potassium uptake in the presence of intracellular nitric oxide (NO), under sodium-free (0-Na+) conditions. METHODS: Sprague Dawley rat colonic crypts were isolated and pHi changes were monitored through the ammonium prepulse technique. Increased proton extrusion in 0-Na+ conditions reflected heightened H+, K+ ATPase activity. Colonic crypts were exposed to penG, L-arginine (a NO precursor), and N-nitro l-arginine methyl ester (L-NAME, a NO synthase inhibitor). RESULTS: Isolated administration of penG significantly increased H+, K+ ATPase activity from baseline, p 0.0067. Co-administration of arginine and penG in 0-Na+ conditions further upregulated H+, K+ ATPase activity, p <0.0001. Crypt perfusion with L-NAME and penG demonstrated a significant reduction in H+, K+ ATPase activity, p 0.0058. CONCLUSION: Overall, acute exposure of colonic crypts to penG activates the H+, K+ ATPase in the presence of NO. This study provides new insights into colonic potassium homeostasis.


Assuntos
Colo/enzimologia , ATPase Trocadora de Hidrogênio-Potássio/metabolismo , Óxido Nítrico/metabolismo , Penicilina G/farmacologia , Animais , Arginina/farmacologia , Masculino , NG-Nitroarginina Metil Éster/farmacologia , Ratos , Ratos Sprague-Dawley
9.
J Clin Endocrinol Metab ; 105(1)2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31529047

RESUMO

PURPOSE: Although preeclampsia (PE) is a well-established cardiovascular risk factor (CVRF) in the general population, its role in type 1 diabetes (T1D) has been scarcely studied. We assessed the association between PE and preclinical atherosclerosis in T1D. METHODS: We recruited 112 women without cardiovascular disease and last pregnancy ≥5 years before: (1) T1D and previous PE (T1D+/PE+; n = 28); (2) T1D without preeclampsia (T1D+/PE-; n = 28); (3) previous PE without T1D (T1D-/PE+; n = 28); and (4) controls (without T1D or PE; T1D-/PE-; n = 28). Groups were matched by age, several CVRFs, and diabetes duration and retinopathy (in T1D participants). Carotid intima-media thickness (IMT) and the presence of plaque (IMT ≥ 1.5 mm) were assessed by standardized ultrasonography protocol. RESULTS: Mean age of the participants was 44.9 ± 7.8 years (14.3% hypertension and 21.4% active smokers). Groups including T1D (T1D+/PE+ and T1D+/PE-) more frequently presented hypertension and statin treatment (23.2% vs 5.4% and 37.5% vs 8.9%; respectively; P < 0.01), without differences in other CVRFs. Carotid plaques were observed in 20.5%. In multivariate models adjusted for age, CVRF, and statins, both T1D and PE showed a similar impact on the presence of plaque, with odds ratios (95% confidence interval), 5.45 (1.36-21.9) and 4.24 (1.04-17.3), respectively. Both entities showed an additive effect when combined, both in common carotid-IMT (T1D+/PE- or T1D-/PE+, ß = 0.198; T1D+/PE+, ß = 0.297) and in the presence of plaque (8.53 [1.07-68.2] and 28.1 [2.67-296.4], respectively). CONCLUSIONS: Previous PE was independently associated with preclinical atherosclerosis in T1D. Further studies are needed to ascertain its usefulness for stratifying risk in T1D women.


Assuntos
Biomarcadores/análise , Doenças das Artérias Carótidas/etiologia , Diabetes Mellitus Tipo 1/fisiopatologia , Pré-Eclâmpsia/fisiopatologia , Adulto , Doenças das Artérias Carótidas/metabolismo , Doenças das Artérias Carótidas/patologia , Espessura Intima-Media Carotídea , Estudos de Casos e Controles , Estudos Transversais , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Gravidez , Prognóstico , Fatores de Risco
10.
Front Physiol ; 10: 439, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31130866

RESUMO

BACKGROUND: The calcium-sensing receptor (CaSR) has been localized and characterized in numerous tissues throughout the body. In the mammalian gastrointestinal tract, the CaSR is known to act as a nutrient sensor and has recently been found to play a role in intestinal fluid and electrolyte balance. This study aims to demonstrate the functionality of the CaSR as a modulator of fluid secretion and absorption along the small intestine. METHODS: Small intestine regions (proximal, middle, and distal) were isolated from Sprague Dawley rats and loaded into an ex vivo intestinal perfusion device that provides independent intraluminal and extraluminal (serosa/basolateral) perfusion. The regions were perfused with 5 and 7 mM of Ca2+, both in the presence and absence of forskolin (FSK), a potent secretagogue. Control experiments were conducted with intraluminal perfusate containing standard Ringer-HEPES buffer with a physiological concentration of Ca2+ (1 mM). A second set of comparison experiments was performed with intraluminal perfusates containing AC-265347, a CaSR activator and agonist, in the presence of FSK. In all experimental conditions, the intraluminal perfusate contained fluorescein isothiocyanate (FITC)-inulin, a nonabsorbable fluorescent marker of secretion and/or absorption. Intraluminal fluorescence signal was utilized as a measure of water movement at the start of the experiment and every 15 min for 90 min. RESULTS: Under physiological conditions, increasing the concentration of Ca2+ in the luminal perfusate reduced intestinal fluid secretion in all regions. At a Ca2+ concentration of 7 mM, net fluid absorption was observed in all regions. In the presence of FSK, 5 mM Ca2+ significantly decreased fluid secretion and 7 mM Ca2+ abolished FSK-induced fluid secretion. Intraluminal perfusion with 5 mM Ca2+ was as effective as AC-265347, in reducing secretagogue-induced fluid hypersecretion in the proximal and middle regions. CONCLUSION: This study concludes that apical CaSR is active along the small intestine. Its activation by Ca2+ and/or calcimimetics reduces fluid secretion in a dose-dependent manner, with higher Ca2+ concentrations, or application of a calcimimetic, leading to fluid absorption. We furthermore show that, in the presence of FSK, receptor activation abates FSK secretagogue-induced fluid secretion. This presents a new therapeutic target to address secretory diarrheal illnesses.

11.
Future Med Chem ; 11(8): 847-855, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30994367

RESUMO

Gastrointestinal illnesses pose a significant worldwide disease burden and are associated with an array of medicinal and surgical therapies. Standard pharmaceutical options have adverse effects, prompting the rise of nutraceutical or food-derivative therapies. Here, we present an overview of the current nutraceutical therapies in gastrointestinal disease. We then introduce the calcium-sensing receptor (CaSR) as a novel therapeutic target. A G-protein-coupled receptor found in apical and basal intestinal cells, the CaSR modulates intestinal fluid secretion and mucosal integrity. Applying nutraceuticals that upregulate the CaSR may alleviate symptoms seen across a spectrum of illnesses. At last, we discuss how nanoparticle technology can be implemented to effectively deliver nutraceuticals to diseased regions of the intestine, thereby minimizing systemic side effects.


Assuntos
Suplementos Nutricionais , Gastroenteropatias/terapia , Animais , Suplementos Nutricionais/análise , Gastroenteropatias/metabolismo , Gastroenteropatias/patologia , Humanos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Modelos Moleculares , Nanopartículas/uso terapêutico , Receptores de Detecção de Cálcio/metabolismo
12.
Innov Surg Sci ; 3(3): 203-213, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31579784

RESUMO

Vascular disease - including coronary artery disease, carotid artery disease, and peripheral vascular disease - is a leading cause of morbidity and mortality worldwide. The standard of care for restoring patency or bypassing occluded vessels involves using autologous grafts, typically the saphenous veins or internal mammary arteries. Yet, many patients who need life- or limb-saving procedures have poor outcomes, and a third of patients who need vascular intervention have multivessel disease and therefore lack appropriate vasculature to harvest autologous grafts from. Given the steady increase in the prevalence of vascular disease, there is great need for grafts with the biological and mechanical properties of native vessels that can be used as vascular conduits. In this review, we present an overview of methods that have been employed to generate suitable vascular conduits, focusing on the advances in tissue engineering methods and current three-dimensional (3D) bioprinting methods. Tissue-engineered vascular grafts have been fabricated using a variety of approaches such as using preexisting scaffolds and acellular organic compounds. We also give an extensive overview of the novel use of 3D bioprinting as means of generating new vascular conduits. Different strategies have been employed in bioprinting, and the use of cell-based inks to create de novo structures offers a promising solution to bridge the gap of paucity of optimal donor grafts. Lastly, we provide a glimpse of our work to create scaffold-free, bioreactor-free, 3D bioprinted vessels from a combination of rat vascular smooth muscle cells and fibroblasts that remain patent and retain the tensile and mechanical strength of native vessels.

13.
Glia ; 66(3): 592-605, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29178321

RESUMO

Glucose is a key modulator of feeding behavior. By acting in peripheral tissues and in the central nervous system, it directly controls the secretion of hormones and neuropeptides and modulates the activity of the autonomic nervous system. GLUT2 is required for several glucoregulatory responses in the brain, including feeding behavior, and is localized in the hypothalamus and brainstem, which are the main centers that control this behavior. In the hypothalamus, GLUT2 has been detected in glial cells, known as tanycytes, which line the basal walls of the third ventricle (3V). This study aimed to clarify the role of GLUT2 expression in tanycytes in feeding behavior using 3V injections of an adenovirus encoding a shRNA against GLUT2 and the reporter EGFP (Ad-shGLUT2). Efficient in vivo GLUT2 knockdown in rat hypothalamic tissue was demonstrated by qPCR and Western blot analyses. Specificity of cell transduction in the hypothalamus and brainstem was evaluated by EGFP-fluorescence and immunohistochemistry, which showed EGFP expression specifically in ependymal cells, including tanycytes. The altered mRNA levels of both orexigenic and anorexigenic neuropeptides suggested a loss of response to increased glucose in the 3V. Feeding behavior analysis in the fasting-feeding transition revealed that GLUT2-knockdown rats had increased food intake and body weight, suggesting an inhibitory effect on satiety. Taken together, suppression of GLUT2 expression in tanycytes disrupted the hypothalamic glucosensing mechanism, which altered the feeding behavior.


Assuntos
Comportamento Alimentar/fisiologia , Transportador de Glucose Tipo 2/metabolismo , Hipotálamo/metabolismo , Neuroglia/metabolismo , Saciação/fisiologia , Animais , Peso Corporal , Tronco Encefálico/citologia , Tronco Encefálico/metabolismo , Células Cultivadas , Jejum/metabolismo , Técnicas de Silenciamento de Genes , Transportador de Glucose Tipo 2/genética , Hipotálamo/citologia , Masculino , Neuroglia/citologia , Neuropeptídeos/metabolismo , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley
14.
Vet Microbiol ; 180(1-2): 136-41, 2015 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-26345258

RESUMO

Coxiella burnetii is the etiological agent of Q fever or Coxiellosis, a zoonosis mainly affecting domestic ruminants. Information on the population structure and epidemiology of C. burnetii in animals is scarce in Portugal. Evidence of C. burnetti infection was sought in domestic, wild and captive animals based on the detection of bacterial DNA. Tissue samples from 152 domestic animals (cattle=24, goats=51, sheep=76 and swine=1), 55 wild carnivores (Egyptian mongoose=45, red fox=4, common genet=3, weasel=2 and European badger=1) and 22 zoo animals (antelopes=15, impala=1; rhinoceros=1, deer=2, zebras=2 and giraffe=1) were screened by nested-touchdown PCR. Cloacae swabs from 19 griffon vultures were also analysed. Among the domestic ruminants, goats presented the highest prevalence of infection (23.53%), followed by cattle, (20.83%) and sheep (10.53%). C. burnetii DNA was also detected in five Egyptian mongooses and two antelopes and one giraffe. Using a 6-locus multiple-locus variable-number tandem repeat analysis (MLVA-6) six complete genotypes, T, I and CM and the first reported CN, CO and CP, were identified, respectively, in small ruminants and Egyptian mongooses. Clustering analysis of genotypes exposed four distinct groups, according to detection source, enlightening an apparent association between C. burnetii genotype and host.


Assuntos
Doenças dos Bovinos/microbiologia , Coxiella burnetii/genética , DNA Bacteriano/genética , Doenças das Cabras/microbiologia , Febre Q/veterinária , Doenças dos Ovinos/microbiologia , Animais , Animais Selvagens/microbiologia , Antílopes , Bovinos , Doenças dos Bovinos/epidemiologia , Cervos/genética , Genótipo , Doenças das Cabras/epidemiologia , Cabras/microbiologia , Repetições Minissatélites , Portugal , Febre Q/epidemiologia , Febre Q/microbiologia , Ovinos , Doenças dos Ovinos/epidemiologia , Suínos
15.
J Cell Mol Med ; 19(7): 1471-82, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26081217

RESUMO

Tanycytes are elongated hypothalamic glial cells that cover the basal walls of the third ventricle; their apical regions contact the cerebrospinal fluid (CSF), and their processes reach hypothalamic neuronal nuclei that control the energy status of an organism. These nuclei maintain the balance between energy expenditure and intake, integrating several peripheral signals and triggering cellular responses that modify the feeding behaviour and peripheral glucose homeostasis. One of the most important and well-studied signals that control this process is glucose; however, the mechanism by which this molecule is sensed remains unknown. We along with others have proposed that tanycytes play a key role in this process, transducing changes in CSF glucose concentration to the neurons that control energy status. Recent studies have demonstrated the expression and function of monocarboxylate transporters and canonical pancreatic ß cell glucose sensing molecules, including glucose transporter 2 and glucokinase, in tanycytes. These and other data, which will be discussed in this review, suggest that hypothalamic glucosensing is mediated through a metabolic interaction between tanycytes and neurons through lactate. This article will summarize the recent evidence that supports the importance of tanycytes in hypothalamic glucosensing, and discuss the possible mechanisms involved in this process. Finally, it is important to highlight that a detailed analysis of this mechanism could represent an opportunity to understand the evolution of associated pathologies, including diabetes and obesity, and identify new candidates for therapeutic intervention.


Assuntos
Células Ependimogliais/metabolismo , Glucose/metabolismo , Hipotálamo/citologia , Animais , Comunicação Celular , Glucoquinase/metabolismo , Proteínas Facilitadoras de Transporte de Glucose/metabolismo , Humanos
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