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1.
Br J Nutr ; 127(5): 739-751, 2022 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-33958009

RESUMO

The objective was to establish new diagnostic criteria for undernutrition for the French population, concordant for children aged <18 years and adults aged <70 years, easy to use by health professionals and applicable whatever the situation (in and outpatients). A multi-disciplinary working and a reading group were involved. The procedure was divided into four phases: (1) systematic review and synthesis of the literature; (2) writing of the initial version of the guidelines; (3) reading and (4) finalisation. The literature search included international guidelines, meta-analyses, systematic reviews and randomised control trials from January 2007 to 31 July 2018. A two-step approach was selected: diagnosing undernutrition and then grading its severity. For diagnosis at least one phenotypic criterion associated with at least one aetiologic criterion were required for both children and adults. Phenotypic criteria for children were weight loss, Body Mass Index (BMI) < International Obesity Task Force curve 18·5, weight stagnation, reduction of muscle mass/function; for adults: weight loss, BMI < 18·5 and reduction of muscle mass/function. Aetiological criteria for children and adults were reduction in dietary intake, reduced absorption and hypercatabolism. Phenotypic metrics were used in both children and adults for grading severity (moderate or severe). These new French recommendations integrate the proposals of recent international recommendations combining aetiologic with phenotypic criteria, but for the first time, they are concordant for children and adults. The WHO threshold of 18·5 for BMI was kept as phenotypic criteria because epidemiological data show an increased mortality for that threshold.


Assuntos
Desnutrição , Adulto , Índice de Massa Corporal , Criança , Guias como Assunto , Humanos , Desnutrição/diagnóstico , Desnutrição/epidemiologia , Estado Nutricional , Obesidade , Redução de Peso
2.
Crit Care ; 26(1): 138, 2022 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-35578303

RESUMO

BACKGROUND: Stress hyperglycemia can persist during an intensive care unit (ICU) stay and result in prolonged requirement for insulin (PRI). The impact of PRI on ICU patient outcomes is not known. We evaluated the relationship between PRI and Day 90 mortality in ICU patients without previous diabetic treatments. METHODS: This is a post hoc analysis of the CONTROLING trial, involving 12 French ICUs. Patients in the personalized glucose control arm with an ICU length of stay ≥ 5 days and who had never previously received diabetic treatments (oral drugs or insulin) were included. Personalized blood glucose targets were estimated on their preadmission usual glycemia as estimated by their glycated A1c hemoglobin (HbA1C). PRI was defined by insulin requirement. The relationship between PRI on Day 5 and 90-day mortality was assessed by Cox survival models with inverse probability of treatment weighting (IPTW). Glycemic control was defined as at least one blood glucose value below the blood glucose target value on Day 5. RESULTS: A total of 476 patients were included, of whom 62.4% were male, with a median age of 66 (54-76) years. Median values for SAPS II and HbA1C were 50 (37.5-64) and 5.7 (5.4-6.1)%, respectively. PRI was observed in 364/476 (72.5%) patients on Day 5. 90-day mortality was 23.1% in the whole cohort, 25.3% in the PRI group and 16.1% in the non-PRI group (p < 0.01). IPTW analysis showed that PRI on Day 5 was not associated with Day 90 mortality (IPTWHR = 1.22; CI 95% 0.84-1.75; p = 0.29), whereas PRI without glycemic control was associated with an increased risk of death at Day 90 (IPTWHR = 3.34; CI 95% 1.26-8.83; p < 0.01). CONCLUSION: In ICU patients without previous diabetic treatments, only PRI without glycemic control on Day 5 was associated with an increased risk of death. Additional studies are required to determine the factors contributing to these results.


Assuntos
Estado Terminal , Hiperglicemia , Insulina , Idoso , Glicemia/metabolismo , Estado Terminal/mortalidade , Estado Terminal/terapia , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Hiperglicemia/sangue , Hiperglicemia/tratamento farmacológico , Hiperglicemia/mortalidade , Insulina/administração & dosagem , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto
3.
BMC Biol ; 19(1): 228, 2021 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-34674701

RESUMO

BACKGROUND: Mitochondrial nucleoside diphosphate kinase (NDPK-D, NME4, NM23-H4) is a multifunctional enzyme mainly localized in the intermembrane space, bound to the inner membrane. RESULTS: We constructed loss-of-function mutants of NDPK-D, lacking either NDP kinase activity or membrane interaction and expressed mutants or wild-type protein in cancer cells. In a complementary approach, we performed depletion of NDPK-D by RNA interference. Both loss-of-function mutations and NDPK-D depletion promoted epithelial-mesenchymal transition and increased migratory and invasive potential. Immunocompromised mice developed more metastases when injected with cells expressing mutant NDPK-D as compared to wild-type. This metastatic reprogramming is a consequence of mitochondrial alterations, including fragmentation and loss of mitochondria, a metabolic switch from respiration to glycolysis, increased ROS generation, and further metabolic changes in mitochondria, all of which can trigger pro-metastatic protein expression and signaling cascades. In human cancer, NME4 expression is negatively associated with markers of epithelial-mesenchymal transition and tumor aggressiveness and a good prognosis factor for beneficial clinical outcome. CONCLUSIONS: These data demonstrate NME4 as a novel metastasis suppressor gene, the first localizing to mitochondria, pointing to a role of mitochondria in metastatic dissemination.


Assuntos
Neoplasias , Núcleosídeo-Difosfato Quinase , Animais , Membranas Intracelulares , Camundongos , Mitocôndrias , Nucleosídeo NM23 Difosfato Quinases/genética , Nucleosídeo NM23 Difosfato Quinases/metabolismo , Neoplasias/genética , Neoplasias/metabolismo , Nucleosídeo Difosfato Quinase D/metabolismo , Núcleosídeo-Difosfato Quinase/genética , Núcleosídeo-Difosfato Quinase/metabolismo
4.
Diabetes Obes Metab ; 23(3): 664-673, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33269554

RESUMO

Imeglimin is an investigational first-in-class novel oral agent for the treatment of type 2 diabetes (T2D). Several pivotal phase III trials have been completed with evidence of statistically significant glucose lowering and a generally favourable safety and tolerability profile, including the lack of severe hypoglycaemia. Imeglimin's mechanism of action involves dual effects: (a) amplification of glucose-stimulated insulin secretion (GSIS) and preservation of ß-cell mass; and (b) enhanced insulin action, including the potential for inhibition of hepatic glucose output and improvement in insulin signalling in both liver and skeletal muscle. At a cellular and molecular level, Imeglimin's underlying mechanism may involve correction of mitochondrial dysfunction, a common underlying element of T2D pathogenesis. It has been observed to rebalance respiratory chain activity (partial inhibition of Complex I and correction of deficient Complex III activity), resulting in reduced reactive oxygen species formation (decreasing oxidative stress) and prevention of mitochondrial permeability transition pore opening (implicated in preventing cell death). In islets derived from diseased rodents with T2D, Imeglimin also enhances glucose-stimulated ATP generation and induces the synthesis of nicotinamide adenine dinucleotide (NAD+ ) via the 'salvage pathway'. In addition to playing a key role as a mitochondrial co-factor, NAD+ metabolites may contribute to the increase in GSIS (via enhanced Ca++ mobilization). Imeglimin has also been shown to preserve ß-cell mass in rodents with T2D. Overall, Imeglimin appears to target a key root cause of T2D: defective cellular energy metabolism. This potential mode of action is unique and has been shown to differ from that of other major therapeutic classes, including biguanides, sulphonylureas and glucagon-like peptide-1 receptor agonists.


Assuntos
Diabetes Mellitus Tipo 2 , Células Secretoras de Insulina , Diabetes Mellitus Tipo 2/tratamento farmacológico , Glucose , Humanos , Hipoglicemiantes/uso terapêutico , Insulina , Triazinas
5.
J Exp Biol ; 222(Pt 10)2019 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-31019067

RESUMO

It is now well established that the intrauterine environment is of major importance for offspring health during later life. Endurance training during pregnancy is associated with positive metabolic adjustments and beneficial effects on the balance between pro-oxidants and antioxidants (redox state) in the offspring. Our hypothesis was that these changes could rely on mitochondrial adaptations in the offspring due to modifications of the fetal environment induced by maternal endurance training. Therefore, we compared the liver and skeletal muscle mitochondrial function and the redox status of young rats whose mothers underwent moderate endurance training (treadmill running) before and during gestation (T) with those of young rats from untrained mothers (C). Our results show a significant reduction in the spontaneous H2O2 release by liver and muscle mitochondria in the T versus C offspring (P<0.05). These changes were accompanied by alterations in oxygen consumption. Moreover, the percentage of short-chain fatty acids increased significantly in liver mitochondria from T offspring. This may lead to improvements in the fluidity and the flexibility of the membrane. In plasma, glutathione peroxidase activity and protein oxidation were significantly higher in T offspring than in C offspring (P<0.05). Such changes in plasma could represent an adaptive signal transmitted from mothers to their offspring. We thus demonstrated for the first time, to our knowledge, that it is possible to act on bioenergetic function including alterations of mitochondrial function in offspring by modifying maternal physical activity before and during pregnancy. These changes could be crucial for the future health of the offspring.


Assuntos
Fígado/metabolismo , Mitocôndrias/metabolismo , Mães , Músculo Esquelético/metabolismo , Condicionamento Físico Animal , Animais , Feminino , Membro Posterior/fisiologia , Masculino , Mitocôndrias Hepáticas/metabolismo , Gravidez , Ratos , Ratos Wistar
6.
Eur Arch Otorhinolaryngol ; 275(5): 1049-1058, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29569135

RESUMO

PURPOSE: The goal of this review is to raise awareness about refeeding syndrome (RFS) and to give a comprehensive presentation of recent guidelines and latest scientific data about nutritional management among head and neck cancer (HNC) patients while focusing on RFS prevention. METHODS: A review of literature for nutritional assessment and RFS management was conducted. Electronic searches of Medline, Cochrane, PubMed and Embase databases for articles published in peer-reviewed journals were conducted from February to September 2017 using the keywords: "nutrition assessment", "head and neck cancer", "refeeding syndrome" and "guidelines". Articles, reviews, book references as well as national and international guidelines in English and French were included. RESULTS: The prevalence of malnutrition is high in HNC patients and a large number of them will need artificial nutritional support or refeeding intervention. RFS is characterized by fluid and electrolyte imbalance associated with clinical manifestations induced by rapid refeeding after a period of malnutrition or starvation. Regarding risk factors for malnutrition and RFS, HNC patients are particularly vulnerable. However, RFS remains unrecognized among head and neck surgeons and medical teams. Practical data are summarized to help organizing nutritional assessment and refeeding interventions. It also summarizes preventive measures to reduce RFS incidence and morbidity in HNC population. CONCLUSION: Nutritional assessment and early refeeding interventions are crucial for HNC patients care. As prevention is the key for RFS management, early identification of patients with high risks is crucial and successful nutritional management requires a multidisciplinary approach.


Assuntos
Neoplasias de Cabeça e Pescoço/complicações , Síndrome da Realimentação/etiologia , Síndrome da Realimentação/prevenção & controle , Humanos , Desnutrição/diagnóstico , Desnutrição/epidemiologia , Desnutrição/etiologia , Desnutrição/terapia , Avaliação Nutricional , Apoio Nutricional/efeitos adversos , Apoio Nutricional/métodos , Prevalência , Síndrome da Realimentação/diagnóstico , Síndrome da Realimentação/epidemiologia , Fatores de Risco
7.
J Physiol ; 595(23): 7049-7062, 2017 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-28971475

RESUMO

KEY POINTS: Maternal training during gestation enhances offspring body composition and energy substrates handling in early adulthood. Offspring nutrition also plays a role as some beneficial effects of maternal training during gestation disappear after consumption of a high-fat diet. ABSTRACT: Maternal exercise during gestation has been reported to modify offspring metabolism and health. Whether these effects are exacerbated when offspring are receiving a high-fat diet remains unclear. Our purpose was to evaluate the effect of maternal exercise before and during gestation on the offspring fed a high-fat/high-sucrose diet (HF) by assessing its body composition, pancreatic function and energy substrates handling by two major glucose-utilizing tissues: liver and muscle. Fifteen-week-old nulliparous female Wistar rats exercised 4 weeks before as well as during gestation at a constant submaximal intensity (TR) or remained sedentary (CT). At weaning, pups from each group were fed either a standard diet (TRCD or CTCD) or a high-fat/high-sucrose diet (TRHF or CTHF) for 10 weeks. Offspring from TR dams gained less weight compared to those from CT dams. Selected fat depots were larger with the HF diet compared to control diet (CD) but significantly smaller in TRHF compared to CTHF. Surprisingly, the insulin secretion index was higher in islets from HF offspring compared to CD. TR offspring showed a higher muscle insulin sensitivity estimated by the ratio of phosphorylated protein kinase B to total protein kinase B compared with CT offspring (+48%, P < 0.05). With CD, permeabilized isolated muscle fibres from TR rats displayed a lower apparent affinity constant (Km ) for pyruvate and palmitoyl coenzyme A as substrates compared to the CT group (-46% and -58%, respectively, P < 0.05). These results suggest that maternal exercise has positive effects on young adult offspring body composition and on muscle carbohydrate and lipid metabolism depending on the nutritional status.


Assuntos
Composição Corporal , Dieta Hiperlipídica/efeitos adversos , Sacarose Alimentar/efeitos adversos , Metabolismo Energético , Condicionamento Físico Animal , Animais , Células Cultivadas , Sacarose Alimentar/administração & dosagem , Feminino , Insulina/metabolismo , Secreção de Insulina , Células Secretoras de Insulina/metabolismo , Metabolismo dos Lipídeos , Masculino , Músculo Esquelético/metabolismo , Gravidez , Ratos , Ratos Wistar
8.
Clin Sci (Lond) ; 131(8): 775-790, 2017 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-28250083

RESUMO

Background: Exercise and citrulline (CIT) are both regulators of muscle protein metabolism. However, the combination of both has been under-studied yet may have synergistic effects on muscle metabolism and performance. Methods: Three-month-old healthy male rats were randomly assigned to be fed ad libitum for 4 weeks with either a citrulline-enriched diet (1 g·kg-1·day-1) (CIT) or an isonitrogenous standard diet (by addition of nonessential amino acid) (Ctrl) and trained (running on treadmill 5 days·week-1) (ex) or not. Maximal endurance activity and body composition were assessed, and muscle protein metabolism (protein synthesis, proteomic approach) and energy metabolism [energy expenditure, mitochondrial metabolism] were explored. Results: Body composition was affected by exercise but not by CIT supplementation. Endurance training was associated with a higher maximal endurance capacity than sedentary groups (P<0.001), and running time was 14% higher in the CITex group than the Ctrlex group (139±4 min versus 122±6 min, P<0.05). Both endurance training and CIT supplementation alone increased muscle protein synthesis (by +27% and +33%, respectively, versus Ctrl, P<0.05) with an additive effect (+48% versus Ctrl, P<0.05). Mitochondrial metabolism was modulated by exercise but not directly by CIT supplementation. However, the proteomic approach demonstrated that CIT supplementation was able to affect energy metabolism, probably due to activation of pathways generating acetyl-CoA. Conclusion: CIT supplementation and endurance training in healthy male rats modulates both muscle protein and energy metabolisms, with synergic effects on an array of parameters, including performance and protein synthesis.


Assuntos
Citrulina/farmacologia , Suplementos Nutricionais , Metabolismo Energético/fisiologia , Proteínas Musculares/metabolismo , Condicionamento Físico Animal , Animais , Composição Corporal , Citrulina/administração & dosagem , Metabolismo Energético/efeitos dos fármacos , Mediadores da Inflamação/metabolismo , Masculino , Mitocôndrias Musculares/metabolismo , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Resistência Física/efeitos dos fármacos , Resistência Física/fisiologia , Proteômica/métodos , Distribuição Aleatória , Ratos Wistar
10.
Biochim Biophys Acta ; 1847(6-7): 629-39, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25868875

RESUMO

Deficit in oxygen and energetic substrates delivery is a key factor in islet loss during islet transplantation. Permeability transition pore (PTP) is a mitochondrial channel involved in cell death. We have studied the respective effects of oxygen and energy substrate deprivation on beta cell viability as well as the involvement of oxidative stress and PTP opening. Energy substrate deprivation for 1h followed by incubation in normal conditions led to a cyclosporin A (CsA)-sensitive-PTP-opening in INS-1 cells and human islets. Such a procedure dramatically decreased INS-1 cells viability except when transient removal of energy substrates was performed in anoxia, in the presence of antioxidant N-acetylcysteine (NAC) or when CsA or metformin inhibited PTP opening. Superoxide production increased during removal of energy substrates and increased again when normal energy substrates were restored. NAC, anoxia or metformin prevented the two phases of oxidative stress while CsA prevented the second one only. Hypoxia or anoxia alone did not induce oxidative stress, PTP opening or cell death. In conclusion, energy substrate deprivation leads to an oxidative stress followed by PTP opening, triggering beta cell death. Pharmacological prevention of PTP opening during islet transplantation may be a suitable option to improve islet survival and graft success.


Assuntos
Apoptose/efeitos dos fármacos , Ilhotas Pancreáticas/efeitos dos fármacos , Ilhotas Pancreáticas/metabolismo , Mitocôndrias/efeitos dos fármacos , Proteínas de Transporte da Membrana Mitocondrial/efeitos dos fármacos , Oxigênio/farmacologia , Acetilcisteína/farmacologia , Animais , Células Cultivadas , Metabolismo Energético/efeitos dos fármacos , Citometria de Fluxo , Sequestradores de Radicais Livres/farmacologia , Humanos , Hipoglicemiantes/farmacologia , Hipóxia , Ilhotas Pancreáticas/patologia , Metformina/farmacologia , Microscopia Confocal , Mitocôndrias/metabolismo , Poro de Transição de Permeabilidade Mitocondrial , Estresse Oxidativo/efeitos dos fármacos , Ratos , Espécies Reativas de Oxigênio/metabolismo
11.
Am J Physiol Endocrinol Metab ; 311(2): E508-18, 2016 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-27382034

RESUMO

Only a few studies have explored the effects of maternal exercise during gestation on adult offspring metabolism. We set out to test whether maternal controlled submaximal exercise maintained troughout all gestational periods induces persistant metabolic changes in the offspring. We used a model of 15-wk-old nulliparous female Wistar rats that exercised (trained group) before and during gestation at a submaximal intensity or remained sedentary (control group). At weaning, male offspring from trained dams showed reduced basal glycemia (119.7 ± 2.4 vs. 130.5 ± 4.1 mg/dl, P < 0.05), pancreas relative weight (3.96 ± 0.18 vs. 4.54 ± 0.14 g/kg body wt, P < 0.05), and islet mean area (22,822 ± 4,036 vs. 44,669 ± 6,761 µm(2), P < 0.05) compared with pups from control dams. Additionally, they had better insulin secretory capacity when stimulated by 2.8 mM glucose + 20 mM arginine compared with offspring from control dams (+96%, P < 0.05). At 7 mo of age, offspring from trained mothers displayed altered glucose tolerance (AUC = 15,285 ± 527 vs. 11,898 ± 988 mg·dl(-1)·120 min, P < 0.05) and decreased muscle insulin sensitivity estimated by the phosphorylated PKB/total PKB ratio (-32%, P < 0.05) and tended to have a reduced islet insulin secretory capacity compared with rats from control dams. These results suggest that submaximal maternal exercise modifies short-term male offspring pancreatic function and appears to have rather negative long-term consequences on sedentary adult offspring glucose handling.


Assuntos
Glicemia/metabolismo , Resistência à Insulina , Ilhotas Pancreáticas/patologia , Músculo Esquelético/metabolismo , Condicionamento Físico Animal , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Animais , Western Blotting , Feminino , Glucose/metabolismo , Teste de Tolerância a Glucose , Homeostase , Insulina/metabolismo , Secreção de Insulina , Ilhotas Pancreáticas/metabolismo , Fígado/metabolismo , Masculino , Tamanho do Órgão , Pâncreas/patologia , Fosfoproteínas/metabolismo , Gravidez , Efeitos Tardios da Exposição Pré-Natal/patologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos Wistar , Desmame
12.
Environ Microbiol ; 17(12): 4954-64, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26235304

RESUMO

Gut microbiota richness and stability are important parameters in host-microbe symbiosis. Diet modification, notably using dietary fibres, might be a way to restore a high richness and stability in the gut microbiota. In this work, during a 6-week nutritional trial, 19 healthy adults consumed a basal diet supplemented with 10 or 40 g dietary fibre per day for 5 days, followed by 15-day washout periods. Fecal samples were analysed by a combination of 16S rRNA gene pyrosequencing, intestinal cell genotoxicity assay, metatranscriptomics sequencing approach and short-chain fatty analysis. This short-term change in the dietary fibre level did not have the same impact for all individuals but remained significant within each individual gut microbiota at genus level. Higher microbiota richness was associated with higher microbiota stability upon increased dietary fibre intake. Increasing fibre modulated the expression of numerous microbiota metabolic pathways such as glycan metabolism, with genes encoding carbohydrate-active enzymes active on fibre or host glycans. High microbial richness was also associated with high proportions of Prevotella and Coprococcus species and high levels of caproate and valerate. This study provides new insights on the role of gut microbial richness in healthy adults upon dietary changes and host microbes' interaction.


Assuntos
Dieta/métodos , Fibras na Dieta/administração & dosagem , Ácidos Graxos/análise , Fezes/microbiologia , Microbioma Gastrointestinal/genética , Adulto , Clostridiales/genética , Clostridiales/isolamento & purificação , Suplementos Nutricionais , Feminino , Humanos , Masculino , Prevotella/genética , Prevotella/isolamento & purificação , RNA Ribossômico 16S/genética , Simbiose , Adulto Jovem
13.
Biochem J ; 463(3): e3-5, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-25301073

RESUMO

Metformin is the most widely prescribed drug used to treat patients affected by Type 2 diabetes. Metformin has also been shown to prevent some forms of cell death; however, evidence suggests that it may have anti-neoplastic properties. All of these effects have been attributed to complex I inhibition, but the mechanism by which metformin leads to complex I inhibition is not fully understood. Although it has been reported that the incubation of functionally isolated complex I in the presence of high concentrations of metformin led to its inhibition, much lower concentrations of metformin have been shown to inhibit complex I in intact cells. In a recent issue of the Biochemical Journal, Bridges, Jones, Pollak and Hirst [(2014) Biochem. J. 462, 475-487] studied for the first time the effect of metformin on purified complex I. They report that millimolar concentrations of metformin directly inhibit complex I activity in a non-competitive manner. They also specify that the binding of metformin to complex I depends on its conformation. To explain the difference in concentration required to inhibit complex I in intact cells and on isolated enzyme, Bridges et al. (2014) propose that metformin concentrates within mitochondria in intact cells. Albeit theoretically plausible, this attractive hypothesis is not directly tested by Bridges et al. (2014) Moreover, although sparse, the current literature does not support this hypothesis.


Assuntos
Biguanidas/farmacologia , Complexo I de Transporte de Elétrons/efeitos dos fármacos , Metformina/farmacologia , Mitocôndrias Cardíacas/efeitos dos fármacos , Mitocôndrias Hepáticas/efeitos dos fármacos , Fosforilação Oxidativa/efeitos dos fármacos , Animais , Humanos
14.
J Neurochem ; 131(3): 314-22, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24989320

RESUMO

Since emotional stress elicits brain activation, mitochondria should be a key component of stressed brain response. However, few studies have focused on mitochondria functioning in these conditions. In this work, we aimed to determine the effects of an acute restraint stress on rat brain mitochondrial functions, with a focus on permeability transition pore (PTP) functioning. Rats were divided into two groups, submitted or not to an acute 30-min restraint stress (Stress, S-group, vs. Control, C-group). Brain was removed immediately after stress. Mitochondrial respiration and enzymatic activities (complex I, complex II, hexokinase) were measured. Changes in PTP opening were assessed by the Ca(2+) retention capacity. Cell signaling pathways relevant to the coupling between mitochondria and cell function (adenosine monophosphate-activated protein kinase, phosphatidylinositol 3-kinase, glycogen synthase kinase 3 beta, MAPK, and cGMP/NO) were measured. The effect of glucocorticoids was also assessed in vitro. Stress delayed (43%) the opening of PTP and resulted in a mild inhibition of complex I respiratory chain. This inhibition was associated with significant stress-induced changes in adenosine monophosphate-activated protein kinase signaling pathway without changes in brain cGMP level. In contrast, glucocorticoids did not modify PTP opening. These data suggest a rapid adaptive mechanism of brain mitochondria in stressed conditions, with a special focus on PTP regulation. In a rat model of acute restraint stress, we observed substantial changes in brain mitochondria functioning. Stress significantly (i) delays (43%) the opening of permeability transition pore (PTP) by the calcium (Ca(2+) ), its main inductor and (ii) results in an inhibition of complex I in electron transport chain associated with change in AMPK signaling pathway. These data suggest an adaptive mechanism of brain mitochondria in stressed condition, with a special focus on PTP regulation.


Assuntos
Encéfalo/patologia , Proteínas de Transporte da Membrana Mitocondrial/fisiologia , Estresse Psicológico/patologia , Animais , Encéfalo/efeitos dos fármacos , Cálcio/metabolismo , GMP Cíclico/metabolismo , Glucocorticoides/farmacologia , Masculino , Poro de Transição de Permeabilidade Mitocondrial , Consumo de Oxigênio/efeitos dos fármacos , Permeabilidade , Ratos , Ratos Wistar , Transdução de Sinais/efeitos dos fármacos
15.
Microcirculation ; 21(1): 84-92, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23952930

RESUMO

OBJECTIVE: Several works highlight the role of CsA in the prevention of IRI, but none focus on isolated lungs. Our objective was to evaluate the effects of CsA on IRI on ex vivo reperfused pig lungs. METHODS: Thirty-two pairs of pig lungs were collected and stored for 30 minutes at 4 °C. The study was performed in four groups. First, a control group and then three groups receiving different concentrations of CsA (1, 10, and 30 µM) at two different times: once at the moment of lung procurement and another during the reperfusion procedure. The ex vivo lung preparation was set up using an extracorporeal perfusion circuit. Gas exchange parameters, pulmonary hemodynamics, and biological markers of lung injury were collected for the evaluation. RESULTS: CsA improved the PaO2 /FiO2 ratio, but it also increased PAP, Pcap, and pulmonary vascular resistances with dose-dependent effects. Lungs treated with high doses of CsA displayed higher capillary-alveolar permeability to proteins, lower AFC capacities, and elevated concentrations of pro-inflammatory cytokines. CONCLUSIONS: These data suggest a possible deleterious imbalance between the beneficial cell properties of CsA in IRI and its hemodynamic effects on microvascularization.


Assuntos
Permeabilidade Capilar/efeitos dos fármacos , Ciclosporina/farmacologia , Imunossupressores/farmacologia , Lesão Pulmonar , Alvéolos Pulmonares , Troca Gasosa Pulmonar/efeitos dos fármacos , Animais , Citocinas/metabolismo , Lesão Pulmonar/metabolismo , Lesão Pulmonar/patologia , Lesão Pulmonar/fisiopatologia , Perfusão , Alvéolos Pulmonares/metabolismo , Alvéolos Pulmonares/patologia , Alvéolos Pulmonares/fisiopatologia , Suínos
16.
Crit Care ; 18(4): 163, 2014 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-25043707

RESUMO

In a recent issue of Critical Care, 0.5 M sodium lactate infusion for 24 hours was reported to increase cardiac output in patients with acute heart failure. This effect was associated with a concomitant metabolic alkalosis and a negative water balance. Growing data strongly support the role of lactate as a preferential oxidizable substrate to supply energy metabolism leading to improved organ function (heart and brain especially) in ischemic conditions. Due to its sodium/chloride imbalance, this solution prevents hyperchloremic acidosis and limits fluid overload despite the obligatory high sodium load. Sodium lactate solution therefore shows many advantages and appears a very promising means for resuscitation of critically ill patients. Further studies are needed to establish the most appropriate dose and indications for sodium lactate infusion in order to prevent the occurrence of severe hypernatremia and metabolic alkalosis.


Assuntos
Desequilíbrio Ácido-Base/prevenção & controle , Hidratação/métodos , Insuficiência Cardíaca/tratamento farmacológico , Lactato de Sódio/uso terapêutico , Desequilíbrio Hidroeletrolítico/induzido quimicamente , Desequilíbrio Ácido-Base/etiologia , Acidose/etiologia , Acidose/prevenção & controle , Alcalose/prevenção & controle , Biomarcadores , Débito Cardíaco/efeitos dos fármacos , Humanos , Hiperlactatemia/induzido quimicamente , Hiperlactatemia/prevenção & controle , Hipernatremia/induzido quimicamente , Hipernatremia/prevenção & controle , Hipopotassemia/induzido quimicamente , Hipopotassemia/prevenção & controle , Prognóstico , Lactato de Sódio/administração & dosagem , Lactato de Sódio/efeitos adversos , Volume Sistólico/efeitos dos fármacos , Equilíbrio Hidroeletrolítico/efeitos dos fármacos , Desequilíbrio Hidroeletrolítico/prevenção & controle
17.
Crit Care ; 18(6): 599, 2014 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-25673151

RESUMO

Hyperosmolar lactate-based solutions have been used for fluid resuscitation in ICU patients. The positive effects observed with these fluids have been attributed to both lactate metabolism and the hypertonic nature of the solutions. In a recent issue of Critical Care, Duburcq and colleagues studied three types of fluid infused at the same volume in a porcine model of endotoxic shock. The control group was resuscitated with 0.9% NaCl, and the two other groups received either hypertonic sodium-lactate or hypertonic sodium-bicarbonate. The two hypertonic fluids proved to be more effective than 0.9% NaCl for resuscitation in this model. However, some parameters were more effectively corrected by hypertonic sodium-lactate than by hypertonic sodium-bicarbonate, suggesting that lactate metabolism was beneficial in these cases.


Assuntos
Hidratação , Hemodinâmica/efeitos dos fármacos , Microcirculação/efeitos dos fármacos , Choque Séptico/tratamento farmacológico , Lactato de Sódio/uso terapêutico , Equilíbrio Hidroeletrolítico/efeitos dos fármacos , Animais , Feminino
18.
Crit Care ; 18(5): 466, 2014 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-25189175

RESUMO

INTRODUCTION: Dengue shock syndrome (DSS) fluid resuscitation by following the World Health Organization (WHO) guideline usually required large volumes of Ringer lactate (RL) that might induce secondary fluid overload. Our objective was to compare the effectiveness of the recommended volume of RL versus a smaller volume of a hypertonic sodium lactate solution (HSL) in children with DSS. The primary end point was to evaluate the effect of HSL on endothelial cell inflammation, assessed by soluble vascular cell adhesion molecule-1 (sVCAM-1) measurements. Secondarily, we considered the effectiveness of HSL in restoring hemodynamic fluid balance, acid-base status, and sodium and chloride balances, as well as in-hospital survival. METHODS: A prospective randomized single-blind clinical trial including 50 DSS children was conducted in the Pediatrics Department of Hasan Sadikin Hospital, Bandung, Indonesia. Only pediatric patients (2 to 14 years old) fulfilling the WHO criteria for DSS and new to resuscitation treatments were eligible. Patients were resuscitated with either HSL (5 ml/kg/BW in 15 minutes followed by 1 ml/kg/BW/h for 12 hours), or RL (20 ml/kg/BW in 15 minutes followed by decreasing doses of 10, 7, 5, and 3 ml/kg BW/h for 12 hours). RESULTS: In total, 50 patients were randomized and included in outcome and adverse-event analysis; 46 patients (8.2 ± 0.5 years; 24.9 ± 1.9 kg; mean ± SEM) completed the protocol and were fully analyzed (24 and 22 subjects in the HSL and RL groups, respectively). Baseline (prebolus) data were similar in both groups. Hemodynamic recovery, plasma expansion, clinical outcome, and survival rate were not significantly different in the two groups, whereas fluid accumulation was one third lower in the HSL than in the RL group. Moreover, HSL was responsible for a partial recovery from endothelial dysfunction, as indicated by the significant decrease in sVCAM-1. CONCLUSION: Similar hemodynamic shock recovery and plasma expansion were achieved in both groups despite much lower fluid intake and fluid accumulation in the HSL group. TRIAL REGISTRATION: ClinicalTrials.gov NCT00966628. Registered 26 August 2009.


Assuntos
Hidratação , Ressuscitação , Dengue Grave/terapia , Lactato de Sódio/uso terapêutico , Adolescente , Criança , Pré-Escolar , Feminino , Hidratação/métodos , Humanos , Indonésia , Soluções Isotônicas/uso terapêutico , Masculino , Estudos Prospectivos , Lactato de Ringer , Método Simples-Cego , Resultado do Tratamento , Molécula 1 de Adesão de Célula Vascular/sangue
19.
Angew Chem Int Ed Engl ; 53(26): 6655-8, 2014 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-24854602

RESUMO

Mitochondria consume oxygen in the respiratory chain and convert redox energy into ATP. As a side process, they produce reactive oxygen species (ROS), whose physiological activities are still not understood. However, current analytical methods cannot be used to monitor mitochondrial ROS quantitatively and unambiguously. We have developed electrochemical biosensors based on peroxidase-redox polymer-modified electrodes, providing selective detection of H2O2 with nanomolar sensitivity, linear response over five concentration decades, and fast response time. The release of H2O2 by mitochondria was then monitored under phosphorylating or inhibited respiration conditions. We report the detection of two concomitant regimes of H2O2 release: large fluxes (hundreds of nM) under complex III inhibition, and bursts of a few nM immediately following mitochondria activation. These unprecedented bursts of H2O2 are assigned to the role of mitochondria as the hub of redox signaling in cells.


Assuntos
Técnicas Eletroquímicas , Peróxido de Hidrogênio/análise , Mitocôndrias/metabolismo , Técnicas Biossensoriais , Carbono/química , Eletrodos , Peroxidase do Rábano Silvestre/metabolismo , Peróxido de Hidrogênio/metabolismo , Oxirredução , Polímeros/química , Saccharomyces cerevisiae/metabolismo
20.
Fr J Urol ; 34(3): 102582, 2024 Feb 15.
Artigo em Francês | MEDLINE | ID: mdl-38364362

RESUMO

INTRODUCTION: A voiding diary (VD) is a key element in the evaluation of patients with overactive bladder (OAB) at initial presentation and during treatment to assess its effectiveness. In order to be clinically relevant, it must be performed over 3 days according to the International Continence Society (ICS). Unfortunately, some patients find it cumbersome. We aimed to evaluate the reliability and patient satisfaction when using a connected tank device. MATERIAL AND METHOD: We conducted a single-center prospective study including 41 patients. Each patient completed a paper voiding diary and then a diary with Diary Pod® (DP) or inversely depending on the study arm. Data from 34 patients were collected. After completion of both diaries, patients completed a satisfaction questionnaire sent by email via GoogleForm. Study statistics were performed with Jamovi® and Excel® software. RESULT: Data from 34 patients were analyzed. There was a statically significant difference (P=0.046) between the mean volume calculated from the paper VD and that calculated from the connected VD (DP). There was no statistically significant difference (P=0.112) between the mean number of daytime voids, mean number of nighttime voids (P=0.156), mean water intake (P=0.183) reported on the paper VD and the connected VD. Thirteen (42%) paper VD and 1 connected VD did not include documentation of the presence or absence of urine leakage or urgency. There was no statistically significant difference between the two calendars regarding the presence or absence of urine leakage (P=0.180) and urinary urgency (P=0.564). Eighty-four percent (26/31) preferred the connected tank to the usual method (paper/pen), while 55% (17/31) and 29% (9/31) of the participants respectively answered that the DP was "very definitely" or "definitely" an aid for performing VD. Nevertheless, 39% (12/31) and 55% (17/31) considered its price to be high or fair and only 22% (7/31) were inclined to buy it. CONCLUSION: This study showed that the Diary connected reservoir Pod® is a reliable and innovative tool for voiding schedules. It facilitates data collection for the majority of patients (83%) and could, through better patient compliance, provide better quality data and help their interpretation by the physician. These factors could encourage the implementation of the connected voiding diary as a diagnostic tool. It would also be used for the assessment of treatment effectiveness in daily clinical practice as well as in research. Its cost remains a major obstacle, judged by 39% of patients to be too high, and could therefore be proposed in specific situations requiring precise data.

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