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1.
Int J Pharm ; 646: 123502, 2023 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-37827392

RESUMO

The increasing prevalence of non-healing infected wounds has become a serious concern in the clinical practice, being associated to population aging and to the rising prevalence of several chronic conditions such as diabetes. Herein, the evaluation of the bactericidal and antibiofilm effects of the natural antiseptic terpenes thymol and farnesol standing alone or in combination with the standard care antiseptic chlorhexidine was carried out both in vitro and in vivo. The in vitro combinatorial treatment of chlorhexidine associated with those terpenes against Staphylococcus aureus in its planktonic and sessile forms demonstrated a superior antibacterial activity than that of chlorhexidine alone. Real-time in vivo monitoring of infection progression and antimicrobial treatment outcomes were evaluated using the bioluminescent S. aureus strain Xen36. In vivo studies on infected wound splinting murine models corroborated the superior bactericidal effects of the combinatorial treatments here proposed. Moreover, the encapsulation of thymol in electrospun Eudragit® S100 (i.e., a synthetic anionic copolymer of methacrylic acid and ethyl acrylate)-based wound dressings was also carried out in order to design efficient antimicrobial wound dressings.


Assuntos
Anti-Infecciosos Locais , Anti-Infecciosos , Infecção dos Ferimentos , Humanos , Animais , Camundongos , Clorexidina/farmacologia , Staphylococcus aureus , Timol/farmacologia , Anti-Infecciosos Locais/farmacologia , Antibacterianos , Anti-Infecciosos/farmacologia , Infecção dos Ferimentos/tratamento farmacológico
2.
Plant Cell Environ ; 45(4): 1315-1332, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35064681

RESUMO

The dynamic behaviour of seeds in soil seed banks depends on their ability to act as sophisticated environmental sensors to adjust their sensitivity thresholds for germination by dormancy mechanisms. Here we show that prolonged incubation of sugar beet fruits at low temperature (chilling at 5°C, generally known to release seed dormancy of many species) can induce secondary nondeep physiological dormancy of an apparently nondormant crop species. The physiological and biophysical mechanisms underpinning this cold-induced secondary dormancy include the chilling-induced accumulation of abscisic acid in the seeds, a reduction in the embryo growth potential and a block in weakening of the endosperm covering the embryonic root. Transcriptome analysis revealed distinct gene expression patterns in the different temperature regimes and upon secondary dormancy induction and maintenance. The chilling caused reduced expression of cell wall remodelling protein genes required for embryo cell elongation growth and endosperm weakening, as well as increased expression of seed maturation genes, such as for late embryogenesis abundant proteins. A model integrating the hormonal signalling and master regulator expression with the temperature-control of seed dormancy and maturation programmes is proposed. The revealed mechanisms of the cold-induced secondary dormancy are important for climate-smart agriculture and food security.


Assuntos
Beta vulgaris , Ácido Abscísico/metabolismo , Beta vulgaris/genética , Germinação/fisiologia , Dormência de Plantas/genética , Sementes/fisiologia
3.
Minerva Med ; 111(5): 427-442, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32955823

RESUMO

Mutations in the FMS-like tyrosine kinase 3 (FLT3) gene arise in 25-30% of all acute myeloid leukemia (AML) patients. These mutations lead to constitutive activation of the protein product and are divided in two broad types: internal tandem duplication (ITD) of the juxtamembrane domain (25% of cases) and point mutations in the tyrosine kinase domain (TKD). Patients with FLT3 ITD mutations have a high relapse risk and inferior cure rates, whereas the role of FLT3 TKD mutations still remains to be clarified. Additionally, growing research indicates that FLT3 status evolves through a disease continuum (clonal evolution), where AML cases can acquire FLT3 mutations at relapse - not present in the moment of diagnosis. Several FLT3 inhibitors have been tested in patients with FLT3-mutated AML. These drugs exhibit different kinase inhibitory profiles, pharmacokinetics and adverse events. First-generation multi-kinase inhibitors (sorafenib, midostaurin, lestaurtinib) are characterized by a broad-spectrum of drug targets, whereas second-generation inhibitors (quizartinib, crenolanib, gilteritinib) show more potent and specific FLT3 inhibition, and are thereby accompanied by less toxic effects. Notwithstanding, all FLT3 inhibitors face primary and acquired mechanisms of resistance, and therefore the combinations with other drugs (standard chemotherapy, hypomethylating agents, checkpoint inhibitors) and its application in different clinical settings (upfront therapy, maintenance, relapsed or refractory disease) are under study in a myriad of clinical trials. This review focuses on the role of FLT3 mutations in AML, pharmacological features of FLT3 inhibitors, known mechanisms of drug resistance and accumulated evidence for the use of FLT3 inhibitors in different clinical settings.


Assuntos
Antineoplásicos/farmacologia , Leucemia Mieloide Aguda/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Sorafenibe/farmacologia , Tirosina Quinase 3 Semelhante a fms/antagonistas & inibidores , Tirosina Quinase 3 Semelhante a fms/genética , Compostos de Anilina/farmacologia , Benzimidazóis/farmacologia , Benzotiazóis/farmacologia , Carbazóis/farmacologia , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Previsões , Furanos , Transplante de Células-Tronco Hematopoéticas , Humanos , Imidazóis/farmacologia , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/terapia , Quimioterapia de Manutenção/métodos , Mutação , Compostos de Fenilureia/farmacologia , Piperidinas/farmacologia , Mutação Puntual , Pirazinas/farmacologia , Piridazinas/farmacologia , Recidiva , Estaurosporina/análogos & derivados , Estaurosporina/farmacologia
4.
Nat Prod Commun ; 12(5): 679-682, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-30496674

RESUMO

Two new fluvirucin aglycones, named fluvirucinins C, and C2 (1-2), have been isolated from the ethyl acetate mycelial cake extract of the fermentation broth of.a marine sponge-associated actinomycete. Fluvirucinins C, (1) and C2 (2) represent a new type of 14-membered macrolactam aglycon, structurally related with the common aglycon of the known fluvirucins. Their structures were elucidated on the basis of ID and 2D NMR analyses, as well as HRESIMS experiments. The antimicrobial and cytotoxic activities of compounds 1 and 2 have been evaluated, but no significant activities found for fluvirucinins C, and C2.


Assuntos
Actinobacteria/metabolismo , Antibacterianos/química , Desoxiaçúcares/química , Lactamas/química , Antibacterianos/isolamento & purificação , Organismos Aquáticos/metabolismo , Desoxiaçúcares/isolamento & purificação , Lactamas/isolamento & purificação , Estrutura Molecular
5.
Gen Comp Endocrinol ; 228: 33-39, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26828819

RESUMO

We aimed to elucidate in rainbow trout (Oncorhynchus mykiss) the effects of central ghrelin (GHRL) treatment on the regulation of liver lipid metabolism, and the possible modulatory effect of central GHRL treatment on the simultaneous effects of raised levels of oleate. Thus, we injected intracerebroventricularly (ICV) rainbow trout GHRL in the presence or absence of oleate and evaluated in liver variables related to lipid metabolism. Oleate treatment elicited in liver of rainbow trout decreased lipogenesis and increased oxidative capacity in agreement with previous studies. Moreover, as demonstrated for the first time in fish in the present study, GHRL also acts centrally modulating lipid metabolism in liver, resulting in increased potential for lipogenesis and decreased potential for fatty acid oxidation, i.e. the converse effects to those elicited by central oleate treatment. The simultaneous treatment of GHRL and oleate confirmed these counteractive effects. Thus, the nutrient sensing mechanisms present in hypothalamus, particularly those involved in sensing of fatty acid, are involved in the control of liver energy metabolism in fish, and this control is modulated by the central action of GHRL. These results give support to the notion of hypothalamus as an integrative place for the regulation of peripheral energy metabolism in fish.


Assuntos
Grelina/farmacologia , Hipotálamo/metabolismo , Metabolismo dos Lipídeos/efeitos dos fármacos , Lipogênese/fisiologia , Fígado/metabolismo , Oncorhynchus mykiss/metabolismo , Animais , Metabolismo Energético/efeitos dos fármacos , Grelina/administração & dosagem , Hipotálamo/efeitos dos fármacos , Infusões Intraventriculares , Lipogênese/efeitos dos fármacos , Fígado/efeitos dos fármacos , Oncorhynchus mykiss/crescimento & desenvolvimento , Oxirredução
6.
J Endocrinol ; 228(1): 25-37, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26459641

RESUMO

There is no information available on fish as far as the possible effects of ghrelin on hypothalamic fatty acid metabolism and the response of fatty acid-sensing systems, which are involved in the control of food intake. Therefore, we assessed in rainbow trout the response of food intake, hypothalamic fatty acid-sensing mechanisms and expression of neuropeptides involved in the control of food intake to the central treatment of ghrelin in the presence or absence of a long-chain fatty acid such as oleate. We observed that the orexigenic actions of ghrelin in rainbow trout are associated with changes in fatty acid metabolism in the hypothalamus and an inhibition of fatty acid-sensing mechanisms, which ultimately lead to changes in the expression of anorexigenic and orexigenic peptides resulting in increased orexigenic potential and food intake. Moreover, the response to increased levels of oleate of hypothalamic fatty acid-sensing systems (activation), expression of neuropeptides (enhanced anorexigenic potential) and food intake (decrease) were counteracted by the simultaneous treatment with ghrelin. These changes provide evidence for the first time in fish of a possible modulatory role of ghrelin on the metabolic regulation by fatty acid of food intake occurring in the hypothalamus.


Assuntos
Ingestão de Alimentos/efeitos dos fármacos , Ácidos Graxos/metabolismo , Grelina/farmacologia , Hipotálamo/efeitos dos fármacos , Oncorhynchus mykiss/fisiologia , Animais , Ingestão de Alimentos/fisiologia , Ácidos Graxos/administração & dosagem , Ácidos Graxos/análise , Expressão Gênica/efeitos dos fármacos , Homeostase/fisiologia , Hipotálamo/fisiologia , Neuropeptídeos/análise , Neuropeptídeos/genética , Ácido Oleico/administração & dosagem , Ácido Oleico/análise , Ácido Oleico/metabolismo , RNA Mensageiro/análise , Reação em Cadeia da Polimerase em Tempo Real/veterinária
7.
J Clin Microbiol ; 53(12): 3766-72, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26378278

RESUMO

Prosthetic joint infection (PJI) is an increasingly important health concern in the Western world due to the rising number of joint arthroplasties. Although most infections are considered to be monomicrobial, the introduction of sonication procedures has led to an increase in the detection of polymicrobial infections. To date, no published studies have investigated the presence of different clones of the same species in the infected patient. The objective of this study was to analyze whether the phenomenon of polyclonality, or the appearance of different clones in the same sample, occurs in PJI. Bacteria isolated by sonication of the retrieved implant from patients with theoretically monomicrobial PJI were included in the study. Two techniques (random amplified polymorphic DNA [RAPD] and matrix-assisted laser desorption ionization-time of flight [MALDI-TOF] mass spectrometry) were used to determine the presence of several clones in the same sample. Results were analyzed to determine bacterial species and infection type (acute versus chronic). RAPD showed a predominance of polyclonal cases (16 of 19). However, when performing the analysis with MALDI-TOF, all cases were shown to be polyclonal. We were unable to establish any relationship between the two methodologies. Polyclonality is a common phenomenon in acute and chronic PJI. Further studies are needed to establish the potential implications of this phenomenon on patient outcomes.


Assuntos
Artrite/microbiologia , Bactérias/classificação , Coinfecção/microbiologia , Infecções Relacionadas à Prótese/microbiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Bactérias/química , Bactérias/genética , Bactérias/isolamento & purificação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Técnica de Amplificação ao Acaso de DNA Polimórfico , Estudos Retrospectivos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
8.
J Exp Biol ; 218(Pt 16): 2610-9, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26089527

RESUMO

Using rainbow trout fed with low-fat or high-fat diets, we aimed to determine whether the response of food intake, mRNA abundance of hypothalamic neuropeptides involved in the metabolic regulation of food intake and fatty acid sensing systems in the hypothalamus and liver are similar to results previously observed when levels of specific fatty acids were raised by injection. Moreover, we also aimed to determine if the phosphorylation state of intracellular energy sensor 5'-AMP-activated protein kinase (AMPK), and proteins involved in cellular signaling such as protein kinase B (Akt) and target of rapamycin (mTOR) display changes that could be related to fatty acid sensing and the control of food intake. The increased levels of fatty acids in the hypothalamus and liver of rainbow trout fed with a high-fat diet only partially activated fatty acid sensing systems and did not elicit changes in food intake, suggesting that the fatty acid sensing response in fish is more dependent on the presence of specific fatty acids, such as oleate or octanoate, rather than to the global increase in fatty acids. We also obtained, for the first time in fish, evidence for the presence and function of energy sensors such as AMPK and proteins involved in cellular signaling, like mTOR and Akt, in the hypothalamus. These proteins in the hypothalamus and liver were generally activated in fish fed the high-fat versus low-fat diet, suggesting that cellular signaling pathways are activated in response to the increased availability of fatty acids.


Assuntos
Gorduras na Dieta/metabolismo , Ingestão de Alimentos/fisiologia , Oncorhynchus mykiss/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Ácidos Graxos/metabolismo , Proteínas de Peixes/metabolismo , Hipotálamo/metabolismo , Fígado/química , Fígado/metabolismo , Neuropeptídeos/metabolismo , RNA Mensageiro/metabolismo
9.
PLoS One ; 10(5): e0128603, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25996158

RESUMO

We hypothesize that glucosensor mechanisms other than that mediated by glucokinase (GK) operate in hypothalamus and hindbrain of the carnivorous fish species rainbow trout and stress affected them. Therefore, we evaluated in these areas changes in parameters which could be related to putative glucosensor mechanisms based on liver X receptor (LXR), mitochondrial activity, sweet taste receptor, and sodium/glucose co-transporter 1 (SGLT-1) 6 h after intraperitoneal injection of 5 mL x Kg(-1) of saline solution alone (normoglycaemic treatment) or containing insulin (hypoglycaemic treatment, 4 mg bovine insulin x Kg(-1) body mass), or D-glucose (hyperglycaemic treatment, 500 mg x Kg(-1) body mass). Half of tanks were kept at a 10 Kg fish mass x m(-3) and denoted as fish under normal stocking density (NSD) whereas the remaining tanks were kept at a stressful high stocking density (70 kg fish mass x m(-3)) denoted as HSD. The results obtained in non-stressed rainbow trout provide evidence, for the first time in fish, that manipulation of glucose levels induce changes in parameters which could be related to putative glucosensor systems based on LXR, mitochondrial activity and sweet taste receptor in hypothalamus, and a system based on SGLT-1 in hindbrain. Stress altered the response of parameters related to these systems to changes in glycaemia.


Assuntos
Glicemia/metabolismo , Glucoquinase/metabolismo , Hipotálamo/metabolismo , Rombencéfalo/metabolismo , Animais , Glucose/farmacologia , Hipoglicemiantes/farmacologia , Hipotálamo/efeitos dos fármacos , Insulina/farmacologia , Receptores X do Fígado , Oncorhynchus mykiss , Receptores Nucleares Órfãos/metabolismo , Rombencéfalo/efeitos dos fármacos , Transportador 1 de Glucose-Sódio/metabolismo , Paladar/fisiologia
10.
Mini Rev Med Chem ; 15(8): 648-58, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25694076

RESUMO

This paper describes our preliminary results on the ADMET, synthesis, biochemical evaluation, and molecular modeling of racemic HuperTacrines (HT), new hybrids resulting from the juxtaposition of huperzine A and tacrine for the potential treatment of Alzheimer's disease (AD). The synthesis of these HT was executed by Friedländer-type reactions of 2-amino-6-oxo-1,6-dihydropyridine-3-carbonitriles, or 7-amino-2-oxo-1,2,3,4-tetrahydro-1,6-naphthyridine- 8-carbonitriles, with cyclohexanone. In the biochemical evaluation, initial and particular attention was devoted to test their toxicity on human hepatoma cells, followed by the in vitro inhibition of human cholinesterases (hAChE, and hBuChE), and the kinetics/mechanism of the inhibition of the most potent HT; simultaneous molecular modeling on the best HT provided the key binding interactions with the human cholinesterases. >From these analyses, (±)-5-amino-3-methyl- 3,4,6,7,8,9-hexahydrobenzo[b][1,8]naphthyridin-2(1H)-one (HT1) and (±)-5-amino-3-(2,6-dichlorophenyl)-3,4,6,7,8,9- hexahydrobenzo[b][1,8]naphthyridin-2(1H)-one (HT3) have emerged as characterized by extremely low liver toxicity reversible mixed-type, selective hAChE and, quite selective irreversible hBuChEIs, respectively, showing also good druglike properties for AD-targeted drugs.


Assuntos
Alcaloides/química , Alcaloides/farmacologia , Doença de Alzheimer/tratamento farmacológico , Inibidores da Colinesterase/química , Inibidores da Colinesterase/farmacologia , Sesquiterpenos/química , Sesquiterpenos/farmacologia , Tacrina/química , Tacrina/farmacologia , Acetilcolinesterase/metabolismo , Alcaloides/toxicidade , Doença de Alzheimer/enzimologia , Inibidores da Colinesterase/toxicidade , Colinesterases/metabolismo , Descoberta de Drogas , Células Hep G2 , Humanos , Modelos Moleculares , Nootrópicos/química , Nootrópicos/farmacologia , Nootrópicos/toxicidade , Sesquiterpenos/toxicidade , Tacrina/toxicidade
11.
Physiol Behav ; 129: 272-9, 2014 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-24631300

RESUMO

If levels of fatty acids like oleate and octanoate are directly sensed through different fatty acid (FA) sensing systems in hypothalamus of rainbow trout, intracerebroventricular (ICV) administration of FA should elicit effects similar to those previously observed after intraperitoneal (IP) treatment. Accordingly, we observed after ICV treatment with oleate or octanoate decreased food intake accompanied in hypothalamus by reduced potential of lipogenesis and FA oxidation, and decreased potential of ATP-dependent inward rectifier potassium channel (K(+)ATP). Those changes support direct FA sensing through mechanisms related to FA metabolism and mitochondrial activity. The FA sensing through binding to FAT/CD36 and subsequent expression of transcription factors appears to be also direct but an interaction with peripheral hormones cannot be rejected. Moreover, decreased expression of NPY and increased expression of POMC were observed in parallel with the activation of FA sensing systems and decreased food intake. These results allow us to suggest the involvement of at least these peptides in controlling the decreased food intake noted after oleate and octanoate treatment in rainbow trout.


Assuntos
Depressores do Apetite/farmacologia , Caprilatos/farmacologia , Ingestão de Alimentos/efeitos dos fármacos , Hipotálamo/efeitos dos fármacos , Ácido Oleico/farmacologia , Oncorhynchus mykiss/metabolismo , Animais , Antígenos CD36/metabolismo , Ingestão de Alimentos/fisiologia , Ácidos Graxos/metabolismo , Proteínas de Peixes/metabolismo , Hipotálamo/metabolismo , Canais KATP/metabolismo , Lipogênese/efeitos dos fármacos , Neuropeptídeo Y/metabolismo , Oxirredução/efeitos dos fármacos , Pró-Opiomelanocortina/metabolismo , RNA Mensageiro/metabolismo , Fatores de Transcrição/metabolismo
12.
PLoS One ; 8(3): e59507, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23533628

RESUMO

In a previous study, we provided evidence for the presence in hypothalamus and Brockmann bodies (BB) of rainbow trout Oncorhynchus mykiss of sensing systems responding to changes in levels of oleic acid (long-chain fatty acid, LCFA) or octanoic acid (medium-chain fatty acid, MCFA). Since those effects could be attributed to an indirect effect, in the present study, we evaluated in vitro if hypothalamus and BB respond to changes in FA in a way similar to that observed in vivo. In a first set of experiments, we evaluated in hypothalamus and BB exposed to increased oleic acic or octanoic acid concentrations changes in parameters related to FA metabolism, FA transport, nuclear receptors and transcription factors, reactive oxygen species (ROS) effectors, components of the KATP channel, and (in hypothalamus) neuropeptides related to food intake. In a second set of experiments, we evaluated in hypothalamus the response of those parameters to oleic acid or octanoic acid in the presence of inhibitors of fatty acid sensing components. The responses observed in vitro in hypothalamus are comparable to those previously observed in vivo and specific inhibitors counteracted in many cases the effects of FA. These results support the capacity of rainbow trout hypothalamus to directly sense changes in MCFA or LCFA levels. In BB increased concentrations of oleic acid or octanoic acid induced changes that in general were comparable to those observed in hypothalamus supporting direct FA sensing in this tissue. However, those changes were not coincident with those observed in vivo allowing us to suggest that the FA sensing capacity of BB previously characterized in vivo is influenced by other neuroendocrine systems.


Assuntos
Caprilatos/farmacologia , Hipotálamo/efeitos dos fármacos , Hipotálamo/metabolismo , Ácido Oleico/farmacologia , Oncorhynchus mykiss/metabolismo , Animais , Ácidos Graxos/metabolismo
13.
Gen Comp Endocrinol ; 178(1): 131-8, 2012 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-22569117

RESUMO

As demonstrated in previous studies, the functioning of brain glucosensing systems in rainbow trout is altered under stress conditions in a way that they are unable to respond properly to changes in glucose levels. Melatonin has been postulated as necessary for homeostatic control of energy metabolism in several vertebrate groups, and in fish it has been suggested as an anti-stress molecule. To evaluate the possible effects of melatonin on glucosensing, we have incubated hypothalamus and hindbrains of rainbow trout at different glucose concentrations in the presence of increased doses (0.01, 1, and 100nM) of melatonin assessing whether or not the responses to changes in glucose levels of parameters related to glucosensing (glucose, glycogen and glucose 6-phosphate levels, activities of GK, GSase and PK, and mRNA content of GK, GLUT2, Kir6.x-like, and SUR-like) are modified in the presence of melatonin. While no effects of melatonin were observed in hindbrain, in hypothalamus melatonin treatment up-regulated glucosensing parameters, especially under hypo- and normo-glycaemic conditions. The effects of melatonin in hypothalamus occurred apparently through MT(1) receptors since most effects were counteracted by the presence of luzindole but not by the presence of 4-P-PDOT. Moreover, melatonin treatment induced in hypothalamus increased mRNA expression levels of NPY and decreased mRNA levels of POMC, CART, and CRF. A role of the hormone in daily re-adjustment of hypothalamic glucosensor machinery is discussed.


Assuntos
Ingestão de Alimentos/efeitos dos fármacos , Hipotálamo/efeitos dos fármacos , Hipotálamo/metabolismo , Melatonina/farmacologia , Peptídeos/genética , Animais , Glucoquinase/genética , Glucose/metabolismo , Glicogênio/metabolismo , Oncorhynchus mykiss , RNA Mensageiro/genética
14.
Am J Physiol Regul Integr Comp Physiol ; 302(11): R1340-50, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22496361

RESUMO

Enhanced lipid levels inhibit food intake in fish but no studies have characterized the possible mechanisms involved. We hypothesize that the presence of fatty acid (FA)-sensing mechanisms could be related to the control of food intake. Accordingly, we evaluated in the hypothalamus, hindbrain, and Brockmann bodies (BB) of rainbow trout changes in parameters related to fatty acid metabolism, transport of FA, nuclear receptors, and transcription factors involved in lipid metabolism, and components of the K(ATP) channel after intraperitoneal administration of different doses of oleic acid (long-chain fatty acid, LCFA) or octanoic acid (medium-chain fatty acid, MCFA). The increase in circulating LCFA or MCFA levels elicited an inhibition in food intake and induced in the hypothalamus a response compatible with fatty acid sensing in which fatty acid metabolism, binding to cluster of differentiation 36 (CD36), and mitochondrial activity are apparently involved, which is similar to that suggested in mammals except for the apparent capacity of rainbow trout to detect changes in MCFA levels. Changes in those hypothalamic pathways can be related to the control of food intake, since food intake was inhibited when FA metabolism was perturbed (using fatty acid synthase or acetyl-CoA carboxylase inhibitors) and changes in mRNA levels of specific neuropeptides such as neuropeptide Y and proopiomelancortin were also noticed. This response seems to be exclusive for the hypothalamus, since the other center controlling food intake (hindbrain) was unaffected by treatments. The results obtained in BB suggest that at least two of the components of a putative fatty acid-sensing system (based on fatty acid metabolism and binding to CD36) could be present. Therefore, the present study provides, for the first time in fish, evidence for a specific role for FA (MCFA and LCFA) as metabolic signals in hypothalamus and BB, where the detection of those FA can be associated with the control of food intake and hormone release.


Assuntos
Regulação do Apetite/efeitos dos fármacos , Glicemia/metabolismo , Ácidos Graxos/metabolismo , Hipotálamo/metabolismo , Oncorhynchus mykiss/metabolismo , Rombencéfalo/metabolismo , Animais , Regulação do Apetite/fisiologia , Caprilatos/farmacologia , Hipotálamo/fisiologia , Ácido Oleico/farmacologia , Oncorhynchus mykiss/fisiologia , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Rombencéfalo/fisiologia
15.
Am J Physiol Lung Cell Mol Physiol ; 302(6): L595-603, 2012 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-22198909

RESUMO

In the pulmonary vasculature, cGMP levels are regulated by soluble guanylate cyclase (sGC) and phosphodiesterase 5 (PDE5). We previously reported that lambs with persistent pulmonary hypertension of the newborn (PPHN) demonstrate increased reactive oxygen species (ROS) and altered sGC and PDE5 activity, with resultant decreased cGMP. The objective of this study was to evaluate the effects of hydrocortisone on pulmonary vascular function, ROS, and cGMP in the ovine ductal ligation model of PPHN. PPHN lambs were ventilated with 100% O(2) for 24 h. Six lambs received 5 mg/kg hydrocortisone every 8 h times three doses (PPHN-hiHC), five lambs received 3 mg/kg hydrocortisone followed by 1 mg·kg(-1)·dose(-1) times two doses (PPHN-loHC), and six lambs were ventilated with O(2) alone (PPHN). All groups were compared with healthy 1-day spontaneously breathing lambs (1DSB). O(2) ventilation of PPHN lambs decreased sGC activity, increased PDE5 activity, and increased ROS vs. 1DSB lambs. Both hydrocortisone doses significantly improved arterial-to-alveolar ratios relative to PPHN lambs, decreased PDE5 activity, and increased cGMP relative to PPHN lambs. High-dose hydrocortisone also increased sGC activity, decreased PDE5 expression, decreased ROS, and increased total vascular SOD activity vs. PPHN lambs. These data suggest that hydrocortisone treatment in clinically relevant doses improves oxygenation and decreases hyperoxia-induced changes in sGC and PDE5 activity, increasing cGMP levels. Hydrocortisone reduces ROS levels in part by increasing SOD activity in PPHN lambs ventilated with 100% O(2.) We speculate that hydrocortisone increases cGMP by direct effects on sGC and PDE5 expression and by attenuating abnormalities induced by oxidant stress.


Assuntos
GMP Cíclico/metabolismo , Hidrocortisona/farmacologia , Oxigênio/metabolismo , Síndrome da Persistência do Padrão de Circulação Fetal/tratamento farmacológico , Síndrome da Persistência do Padrão de Circulação Fetal/metabolismo , Artéria Pulmonar/efeitos dos fármacos , Animais , Animais Recém-Nascidos , Nucleotídeo Cíclico Fosfodiesterase do Tipo 5/genética , Nucleotídeo Cíclico Fosfodiesterase do Tipo 5/metabolismo , Guanilato Ciclase/metabolismo , Humanos , Hiperóxia/tratamento farmacológico , Hiperóxia/genética , Hiperóxia/metabolismo , Hiperóxia/fisiopatologia , Recém-Nascido , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/genética , Síndrome da Persistência do Padrão de Circulação Fetal/genética , Síndrome da Persistência do Padrão de Circulação Fetal/fisiopatologia , Artéria Pulmonar/metabolismo , Artéria Pulmonar/fisiopatologia , Espécies Reativas de Oxigênio/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Ovinos , Guanilil Ciclase Solúvel , Superóxido Dismutase/metabolismo
16.
J Exp Biol ; 214(Pt 22): 3887-94, 2011 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-22031754

RESUMO

Stress conditions induced in rainbow trout a readjustment in the glucosensing response of the hypothalamus and hindbrain such that those sensors did not respond properly to changes in glucose levels, as demonstrated in previous studies. To evaluate the hypothesis that corticotropin-releasing factor (CRF) could be involved in that response, we have incubated the hypothalamus and hindbrain of rainbow trout at different glucose concentrations in the presence of different concentrations of CRF. Under those conditions, we evaluated whether parameters related to glucosensing [the levels of glucose, glycogen and glucose 6-phosphate, the activities of glucokinase (GK), glycogen synthase (GSase) and pyruvate kinase (PK), and mRNA abundance of transcripts for GK, Glut2, Kir.6-like and sulfonylurea receptor (SUR)-like] are modified in the presence of CRF in a way comparable to that observed under stress conditions. We obtained evidence allowing us to suggest that CRF could be involved in the interaction between stress and glucosensing as CRF treatment of the hypothalamus and hindbrain in vitro induced a readjustment in glucosensing parameters similar to that previously observed under stress conditions in vivo. We had also previously demonstrated that stress elicits alterations in food intake in parallel with the readjustment of glucosensing systems. Here, we provide evidence that the mRNA abundance of several of the neuropeptides involved in the regulation of food intake, such as neuropeptide Y (NPY) or cocaine and amphetamine-regulated transcript (CART), is affected by CRF treatment, in such a way that their expression does not respond to changes in glucose levels in the same way as controls, allowing us to suggest that the food intake response that is integrated by changes in those peptides and known to be reduced by stress could be also mediated by CRF action in glucosensing areas.


Assuntos
Hormônio Liberador da Corticotropina/metabolismo , Proteínas de Peixes/metabolismo , Glucose/metabolismo , Hipotálamo/metabolismo , Oncorhynchus mykiss/metabolismo , Animais , Rombencéfalo/metabolismo
17.
Mar Pollut Bull ; 56(5): 869-79, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18334257

RESUMO

The development of aquaculture along the Mediterranean coastline degrades the marine environment, in particular Posidonia oceanica meadows, which, in extreme cases, show high mortality. Here we studied the effects of organic matter and nutrient input from the effluents of three fish farms, located along the Mediterranean coast, on P. oceanica physiology. For this purpose, we measured physiological variables such as total nitrogen (N) content, free amino acid (FAA) concentration and composition, N stable isotope ratio (delta 15N), total phosphorus (P) content and total non-structural carbohydrate (TNC) content in plant tissues and epiphytes affected by organic discharges (highly impacted stations: HI, and less impacted stations: LI) and compared these results with those obtained in references sites (control stations: C). For all the descriptors analyzed in P. oceanica epiphytes, the values recorded in the vicinity of cages were, in general, much higher than those in C. Leaves did not respond consistently in any case. Total N content and delta 15N in epiphytes together with the total P content in rhizomes and epiphytes were the physiological descriptors that showed the most consistent responses to fish farm effluents. On the basis of these observations, we conclude that fish farm activities strongly affect the physiological parameters of nearby P. oceanica meadows. We propose that changes in these physiological parameters may be useful indicators of marine environmental degradation in studies that monitor the effects of fish farming.


Assuntos
Alismatales/metabolismo , Aquicultura , Monitoramento Ambiental , Eliminação de Resíduos Líquidos , Aminoácidos/metabolismo , Animais , Peixes , Grécia , Itália , Nitrogênio/metabolismo , Isótopos de Nitrogênio/metabolismo , Fósforo/metabolismo , Folhas de Planta/metabolismo , Raízes de Plantas/metabolismo , Rizoma/metabolismo , Espanha
18.
Mar Pollut Bull ; 55(1-6): 196-204, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17045301

RESUMO

We propose here a multivariate index based on structural and functional attributes of the Posidonia oceanica ecosystem (Posidonia oceanica multivariate index: POMI) to assess the ecological status of coastal waters following WFD requirements. POMI is based on the combination, through principal component analysis, of physiological, morphological, structural and community level seagrass descriptors (or metrics), univocally related to environmental quality. Scores on the first axis are normalised to a 0-1 scale (EQR) using reference and worst sites. The index was tested by sampling 22 seagrass beds in the Catalan coast (ca. 500 km, NW Mediterranean). The results show a clustering of variables on both sides of the first axis of the PCA, indicating a common relation of all metrics with ecological status. Moreover, the values (EQR) obtained reflect human pressure levels. The proposed index allows a practical and relatively simple assessment of the ecological status of coastal waters, and contains a considerable amount of ecological information, which can be useful for managing purposes.


Assuntos
Alismatales/crescimento & desenvolvimento , Ecossistema , Monitoramento Ambiental/métodos , Monitoramento Ambiental/normas , Alismatales/química , Cooperação Internacional/legislação & jurisprudência , Mar Mediterrâneo , Metais Pesados/análise , Modelos Teóricos , Análise Multivariada , Nitrogênio/análise , Fósforo/análise , Densidade Demográfica , Análise de Componente Principal , Padrões de Referência , Espanha , Enxofre/análise
19.
Cir Esp ; 80(6): 403-5, 2006 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-17192226

RESUMO

The antegrade continent enema procedure was first described in 1990 by Malone for the treatment of severe fecal neurogenic incontinence in children. Since then, this technique has been successfully carried out in adults, as well as in patients with refractory constipation. The procedure provides a continent and catheterizable channel, generally an appendicostomy, through which antegrade washouts are given to produce colonic emptying. We describe the case of a 23-year-old man with severe constipation and overflow fecal incontinence who underwent an appendicostomy. There were no immediate postoperative complications and saline washouts were started on the fourth day. Since then, the patient has had a bowel movement between 1 and 3 hours after each washout, has recovered continence, and no longer wears an absorbent pad.


Assuntos
Apêndice/cirurgia , Constipação Intestinal/terapia , Enema/métodos , Adulto , Cateterismo , Cecostomia , Doença Crônica , Incontinência Fecal/terapia , Humanos , Masculino , Fatores de Tempo , Resultado do Tratamento
20.
Cir. Esp. (Ed. impr.) ; 80(6): 403-405, dic. 2006. ilus
Artigo em Es | IBECS | ID: ibc-049483

RESUMO

La técnica del enema anterógrado continente fue descrita por primera vez por Malone en 1990 para el tratamiento de la incontinencia fecal grave de origen neurogénico en niños, y posteriormente se ha utilizado con éxito también en adultos y en pacientes con estreñimiento que no responde al tratamiento médico. El procedimiento consiste en la formación de un conducto continente, generalmente una apendicostomía, que permita la cateterización intermitente para la irrigación y la limpieza rápida y controlada del colon. Presentamos el caso de un paciente de 23 años con estreñimiento grave y encopresis al que se le practicó una apendicostomía. No hubo complicaciones postoperatorias inmediatas y las irrigaciones se iniciaron con suero salino el cuarto día después de la intervención. Desde entonces, el paciente realiza deposiciones entre 1 y 3 h después del lavado, ha recuperado la continencia y ha dejado de llevar pañales (AU)


The antegrade continent enema procedure was first described in 1990 by Malone for the treatment of severe fecal neurogenic incontinence in children. Since then, this technique has been successfully carried out in adults, as well as in patients with refractory constipation. The procedure provides a continent and catheterizable channel, generally an appendicostomy, through which antegrade washouts are given to produce colonic emptying. We describe the case of a 23-year-old man with severe constipation and overflow fecal incontinence who underwent an appendicostomy. There were no immediate postoperative complications and saline washouts were started on the fourth day. Since then, the patient has had a bowel movement between 1 and 3 hours after each washout, has recovered continence, and no longer wears an absorbent pad (AU)


Assuntos
Masculino , Adulto , Humanos , Constipação Intestinal/cirurgia , Enema/métodos , Incontinência Fecal/cirurgia , Estomas Cirúrgicos , Síndrome do Cromossomo X Frágil/complicações
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