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1.
Cell Death Dis ; 15(5): 311, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38697987

RESUMO

Cancer cells are highly dependent on bioenergetic processes to support their growth and survival. Disruption of metabolic pathways, particularly by targeting the mitochondrial electron transport chain complexes (ETC-I to V) has become an attractive therapeutic strategy. As a result, the search for clinically effective new respiratory chain inhibitors with minimized adverse effects is a major goal. Here, we characterize a new OXPHOS inhibitor compound called MS-L6, which behaves as an inhibitor of ETC-I, combining inhibition of NADH oxidation and uncoupling effect. MS-L6 is effective on both intact and sub-mitochondrial particles, indicating that its efficacy does not depend on its accumulation within the mitochondria. MS-L6 reduces ATP synthesis and induces a metabolic shift with increased glucose consumption and lactate production in cancer cell lines. MS-L6 either dose-dependently inhibits cell proliferation or induces cell death in a variety of cancer cell lines, including B-cell and T-cell lymphomas as well as pediatric sarcoma. Ectopic expression of Saccharomyces cerevisiae NADH dehydrogenase (NDI-1) partially restores the viability of B-lymphoma cells treated with MS-L6, demonstrating that the inhibition of NADH oxidation is functionally linked to its cytotoxic effect. Furthermore, MS-L6 administration induces robust inhibition of lymphoma tumor growth in two murine xenograft models without toxicity. Thus, our data present MS-L6 as an inhibitor of OXPHOS, with a dual mechanism of action on the respiratory chain and with potent antitumor properties in preclinical models, positioning it as the pioneering member of a promising drug class to be evaluated for cancer therapy. MS-L6 exerts dual mitochondrial effects: ETC-I inhibition and uncoupling of OXPHOS. In cancer cells, MS-L6 inhibited ETC-I at least 5 times more than in isolated rat hepatocytes. These mitochondrial effects lead to energy collapse in cancer cells, resulting in proliferation arrest and cell death. In contrast, hepatocytes which completely and rapidly inactivated this molecule, restored their energy status and survived exposure to MS-L6 without apparent toxicity.


Assuntos
Antineoplásicos , Proliferação de Células , Complexo I de Transporte de Elétrons , Mitocôndrias , Proteínas de Saccharomyces cerevisiae , Animais , Humanos , Complexo I de Transporte de Elétrons/metabolismo , Complexo I de Transporte de Elétrons/antagonistas & inibidores , Antineoplásicos/farmacologia , Camundongos , Linhagem Celular Tumoral , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Desacopladores/farmacologia , Fosforilação Oxidativa/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/efeitos dos fármacos , Ratos , NADH Desidrogenase/metabolismo , NADH Desidrogenase/antagonistas & inibidores
2.
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.

3.
Med Phys ; 50(8): 4973-4980, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36724170

RESUMO

BACKGROUND: Measurement of cross-sectional muscle area (CSMA) at the mid third lumbar vertebra (L3) level from computed tomography (CT) images is becoming one of the reference methods for sarcopenia diagnosis. However, manual skeletal muscle segmentation is tedious and is thus restricted to research. Automated solutions are required for use in clinical practice. PURPOSE: The aim of this study was to compare the reliability of two automated solutions for the measurement of CSMA. METHODS: We conducted a retrospective analysis of CT images in our hospital database. We included consecutive individuals hospitalized at the Grenoble University Hospital in France between January and May 2018 with abdominal CT images and sagittal reconstruction. We used two types of software to automatically segment skeletal muscle: ABACS, a module of the SliceOmatic software solution "ABACS-SliceOmatic," and a deep learning-based solution called "AutoMATiCA." Manual segmentation was performed by a medical expert to generate reference data using "SliceOmatic." The Dice similarity coefficient (DSC) was used to measure overlap between the results of the manual and the automated segmentations. The DSC value for each method was compared with the Mann-Whitney U test. RESULTS: A total of 676 hospitalized individuals was retrospectively included (365 males [53.8%] and 312 females [46.2%]). The median DSC for SliceOmatic vs AutoMATiCA (0.969 [5th percentile: 0.909]) was greater than the median DSC for SliceOmatic vs. ABACS-SliceOmatic (0.949 [5th percentile: 0.836]) (p < 0.001). CONCLUSIONS: AutoMATiCA, which used artificial intelligence, was more reliable than ABACS-SliceOmatic for skeletal muscle segmentation at the L3 level in a cohort of hospitalized individuals. The next step is to develop and validate a neural network that can identify L3 slices, which is currently a fastidious process.


Assuntos
Inteligência Artificial , Tomografia Computadorizada por Raios X , Masculino , Feminino , Humanos , Estudos Retrospectivos , Reprodutibilidade dos Testes , Estudos Transversais , Tomografia Computadorizada por Raios X/métodos , Músculo Esquelético/diagnóstico por imagem
4.
Arch Physiol Biochem ; 129(2): 505-518, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33171059

RESUMO

The objective of this study is to investigate the relationship between altered plasma trace elements, particularly selenium (Se), with Hyper-homocysteinemia (HhCys) as a predictive factor of insulin secretion dysfunction. The study is carried out on adult Psammomys obesus, divided in 4 experimental groups: (I) Normoglycemic/Normoinsulinemic; (II) Normoglycemic/Hyperinsulinemic; (III) Hyperglycaemic/Hyperinsulinemic and (IV) Hyperglycaemic/Insulin deficiency with ketoacidosis. The data showed that a drastic depletion of Se plasma levels is positively correlated with HhCys (>15 µmol/L; p < .001), concomitantly with decreased GPx activity, GSH levels, and GSH/GSSG ratio in group IV both in plasma and liver. In contrast, SOD activity is increased (p ≤ .001) in group IV both in plasma and liver. However, plasma Cu and Mn levels increased, while plasma Zn levels decreased in group IV (p < .001). Our study confirms the increase of plasma hCys levels seemed to be a major contributing factor to antioxidant capacities and alters the availability of selenium metabolism by interference with homocysteine synthesis in the insulin secretion deficiency stage.


Assuntos
Diabetes Mellitus Tipo 2 , Hiperglicemia , Hiper-Homocisteinemia , Selênio , Oligoelementos , Animais , Secreção de Insulina , Gerbillinae/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Insulina , Estresse Oxidativo , Hiperglicemia/metabolismo
8.
Biochim Biophys Acta Mol Cell Biol Lipids ; 1867(12): 159223, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35987325

RESUMO

The perinatal exposome can modify offspring metabolism and health later in life. Within this concept, maternal exercise during gestation has been reported modifying offspring glucose sensing and homeostasis, while the impact of such exercise during lactation is little-known. We thus aimed at evaluating short- and long-term effects of it on offspring pancreatic function, assuming a link with changes in breast milk composition. Fifteen-week-old primiparous female Wistar rats exercised during lactation at a constant submaximal intensity (TR) or remained sedentary (CT). Male offspring were studied at weaning and at 7 months of age for growth, pancreas weight, glycemia and insulin responses. Milk protein content was determined by the bicinchoninic acid assay (BCA colorimetric method), and lipid content and fatty acid composition by gas chromatography. Mature milk from TR rats contained significantly less saturated (-7 %) and more monounsaturated (+18 %) and polyunsaturated (PUFA +12 %) fatty acids compared to CT rats, with no difference in total lipid and protein concentrations. In offspring from TR vs CT mothers, fasting glycemia was lower, pancreas weight was higher with a lower insulin content (-37 %) at weaning. Such outcomes were correlated with milk PUFA levels and indices of desaturase or elongase activities. These effects were no longer present at 7 months, whereas a more efficient muscle insulin sensitivity was observed. Maternal training during lactation led to a specific milk phenotype that was associated with a short-term impact on glucose homeostasis and pancreatic function of the male offspring.


Assuntos
Ácidos Graxos , Leite , Condicionamento Físico Animal , Animais , Glicemia/metabolismo , Ácidos Graxos Dessaturases , Elongases de Ácidos Graxos , Ácidos Graxos/análise , Feminino , Homeostase , Insulina/metabolismo , Lactação , Masculino , Leite/química , Proteínas do Leite/análise , Gravidez , Ratos , Ratos Wistar
9.
Nutrients ; 14(15)2022 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-35893898

RESUMO

3,5-Diiodothyronine (3,5-T2) has been shown to exert pleiotropic beneficial effects. In this study we investigated whether 3,5-T2 prevent several energy metabolism disorders related to type 2 diabetes mellitus (T2DM) in gerbils diabetes-prone P. obesus. 157 male gerbils were randomly to Natural Diet (ND-controlled) or a HED (High-Energy Diet) divided in: HED- controlled, HED-3,5-T2 and HED- Placebo groups. 3,5-T2 has been tested at 25 µg dose and was administered under subcutaneous pellet implant during 10 weeks. Isolated hepatocytes were shortly incubated with 3,5-T2 at 10-6 M and 10-9 M dose in the presence energetic substrates. 3,5-T2 treatment reduce visceral adipose tissue, prevent the insulin resistance, attenuated hyperglycemia, dyslipidemia, and reversed liver steatosis in diabetes P. obesus. 3,5-T2 decreased gluconeogenesis, increased ketogenesis and enhanced respiration capacity. 3,5-T2 potentiates redox and phosphate potential both in cytosol and mitochondrial compartment. The use of 3,5-T2 as a natural therapeutic means to regulate cellular energy metabolism. We suggest that 3,5-T2 may help improve the deleterious course of obesity and T2DM, but cannot replace medical treatment.


Assuntos
Diabetes Mellitus Tipo 2 , Animais , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Di-Iodotironinas , Modelos Animais de Doenças , Gerbillinae , Insulina/uso terapêutico , Masculino , Obesidade/tratamento farmacológico , Obesidade/metabolismo , Hormônios Tireóideos
10.
Stud Health Technol Inform ; 290: 1068-1069, 2022 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-35673209

RESUMO

Big Data and Deep Learning approaches offer new opportunities for medical data analysis. With these technologies, PREDIMED, the clinical data warehouse of Grenoble Alps University Hospital, sets up first clinical studies on retrospective data. In particular, ODIASP study, aims to develop and evaluate deep learning-based tools for automatic sarcopenia diagnosis, while using data collected via PREDIMED, in particular, medical images. Here we describe a methodology of data preparation for a clinical study via PREDIMED.


Assuntos
Sarcopenia , Big Data , Data Warehousing , Humanos , Processamento de Imagem Assistida por Computador , Estudos Retrospectivos , Sarcopenia/diagnóstico por imagem
11.
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
12.
Physiol Rep ; 10(5): e15151, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35274817

RESUMO

The global prevalence of type 2 diabetes (T2D) is expected to exceed 642 million people by 2040. Metformin is a widely used biguanide T2D therapy, associated with rare but serious events of lactic acidosis, in particular with predisposing conditions (e.g., renal failure or major surgery). Imeglimin, a recently approved drug, is the first in a new class (novel mode of action) of T2D medicines. Although not a biguanide, Imeglimin shares a chemical moiety with Metformin and also modulates mitochondrial complex I activity, a potential mechanism for Metformin-mediated lactate accumulation. We interrogated the potential for Imeglimin to induce lacticacidosis in relevant animal models and further assessed differences in key mechanisms known for Metformin's effects. In a dog model of major surgery, Metformin or Imeglimin (30-1000 mg/kg) was acutely administered, only Metformin-induced lactate accumulation and pH decrease leading to lactic acidosis with fatality at the highest dose. Rats with gentamycin-induced renal insufficiency received Metformin or Imeglimin (50-100 mg/kg/h), only Metformin increased lactatemia and H+ concentrations with mortality at higher doses. Plasma levels of Metformin and Imeglimin were similar in both models. Mice were chronically treated with Metformin or Imeglimin 200 mg/kg bid. Only Metformin produced hyperlactatemia after acute intraperitoneal glucose loading. Ex vivo measurements revealed higher mitochondrial complex I inhibition with Metformin versus slight effects with Imeglimin. Another mechanism implicated in Metformin's effects on lactate production was assessed: in isolated rat, liver mitochondria exposed to Imeglimin or Metformin, only Metformin (50-250 µM) inhibited the mitochondrial glycerol-3-phosphate dehydrogenase (mGPDH). In liver samples from chronically treated mice, measured mGPDH activity was lower with Metformin versus Imeglimin. These data indicate that the risk of lactic acidosis with Imeglimin treatment may be lower than with Metformin and confirm that the underlying mechanisms of action are distinct, supporting its potential utility for patients with predisposing conditions.


Assuntos
Acidose Láctica , Diabetes Mellitus Tipo 2 , Metformina , Insuficiência Renal , Acidose Láctica/induzido quimicamente , Animais , Diabetes Mellitus Tipo 2/tratamento farmacológico , Cães , Humanos , Hipoglicemiantes/efeitos adversos , Hipoglicemiantes/uso terapêutico , Ácido Láctico , Metformina/efeitos adversos , Metformina/uso terapêutico , Camundongos , Ratos , Triazinas
14.
Biofactors ; 48(1): 181-189, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34882863

RESUMO

Intensive care unit patients and chronic airway inflammatory disease are characterized by chronic systemic hypoxia and inflammation inducing a decrease in nitric oxide release due to impaired l-arginine (ARG) homeostasis. As ARG is synthesized from circulating l-citrulline (CIT), an alteration of CIT production in small intestine by ornithine carbamoyltransferase could be involved. Here, we posit that hypoxia and/or inflammation has effects on ornithine carbamoyltransferase regulation in enterocytes. A duodenal explant incubation model was used. Biopsy specimens taken from 25 selected patients were incubated for 6 h in 4 groups: control, inflammation, hypoxia, and hypoxia + inflammation. At the end of the incubation period, we measured CIT concentration in culture media, ornithine carbamoyltransferase activity, ornithine carbamoyltransferase protein and gene expression, protein expression of enzymes involved in the CIT production pathway, and expression of energy status proteins. Inflammation and/or hypoxia conditions did not affect CIT production. Ornithine carbamoyltransferase activity was increased in hypoxia conditions (p = 0.023). Expression of enzymes implicated in the CIT crossroads pathway and enzymes reflecting energy status variation was not affected by inflammation and hypoxia. Data sets were pooled to evaluate the variability of the four quartiles for each parameter. CIT production was found to increase over the quartiles whereas other parameters remained stable. Our results showed that intestinal CIT production is preserved during inflammation and/or hypoxia, thus confirming the significance of this metabolic pathway. This suggests that the CIT deficiency observed in clinical hypercatabolic states could be a consequence of high utilization for ARG synthesis.


Assuntos
Citrulina , Enterócitos , Arginina/metabolismo , Arginina/farmacologia , Citrulina/metabolismo , Citrulina/farmacologia , Enterócitos/metabolismo , Humanos , Hipóxia/genética , Inflamação/genética
15.
Nutrition ; 93: 111433, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34482098

RESUMO

OBJECTIVES: NutriCoviD30 is a longitudinal multicenter cohort study that aimed to provide nutritional objective data of inpatients during COVID-19 infection. The aims of this study were to describe the nutritional effects of COVID-19 infection on adult inpatients on the short- to mid-term (≤30 d after hospital discharge), using food intake and weight measurements and to identify factors associated with a decrease in food intake and weight. METHODS: Food intake and weight trajectories, as well as clinical signs of the disease, preexisting chronic diseases, and nutritional strategies were collected and analyzed during the course of the disease. Their association was estimated using mixed-effect regression modeling. Patients were recruited from French university hospitals from May to July 2020. For the 403 included patients (mean 62.2 ± 14.2 y of age; 63% men), median (interquartile range [IQR]) hospital length of stay was 13 d (IQR = 8, 20), and 30% of patients were admitted to the intensive care unit. RESULTS: Patients declared a median 70% food intake decrease in the acute phase, and the disease resulted in an average loss of 8% of predisease weight (corresponding to -6.5 kg). Although most patients recovered their usual food intake 1 month after hospital discharge, they only regained half of their weight loss, such that malnutrition, which affected 67% of patients during hospitalization, persisted in 41%. Patients with overweight, obesity, and diabetes reported an additional weight loss of >1.5% of their initial bodyweight during hospitalization and recovery phase. CONCLUSIONS: To prevent malnutrition and its long-term effects, mainly combined with a rapid weight loss predominantly affecting lean body mass, implementation of nutritional support is needed for COVID-19 inpatients. It should be started early in the course of the infection, and be extended up to the recovery phase.


Assuntos
COVID-19 , Ingestão de Alimentos , Pacientes Internados , Redução de Peso , Adulto , Feminino , Humanos , Estudos Longitudinais , Masculino , SARS-CoV-2
16.
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
17.
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
18.
Endocrinol Diabetes Metab ; 4(2): e00211, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33855213

RESUMO

Aims: To understand the mechanism by which imeglimin (a new oral hypoglycemic agent whose phase 3 development program in Japan has now been completed) decreases hepatic glucose production. Materials and methods: We compared the effect of imeglimin and metformin on glucose production, ATP/ADP ratio, oxygen consumption rate, mitochondrial redox potential and membrane potential in primary rat hepatocytes. Results: We found that both imeglimin and metformin dose-dependently decreased glucose production and the ATP/ADP ratio. Moreover, they both increased mitochondrial redox potential (assessed by mitochondrial NAD(P)H fluorescence) and decreased membrane potential (assessed by TMRM fluorescence). However, contrary to metformin, which inhibits mitochondrial Complex I, imeglimin did not decrease the oxygen consumption rate in intact cells. By measuring the oxygen consumption of in situ respiratory chain as a function of the concentration of NADH, we observed that imeglimin decreased the affinity of NADH for the respiratory chain but did not affect its Vmax (ie competitive inhibition) whereas metformin decreased both the Vmax and the affinity (ie uncompetitive inhibition). Conclusions: We conclude that imeglimin induces a kinetic constraint on the respiratory chain that does not affect its maximal activity. This kinetic constraint is offset by a decrease in the mitochondrial membrane potential, which induces a thermodynamic constraint on the ATPase responsible for a decrease in the ATP/ADP ratio.


Assuntos
Gluconeogênese/efeitos dos fármacos , Hepatócitos/metabolismo , Hipoglicemiantes/farmacologia , Triazinas/farmacologia , Difosfato de Adenosina/metabolismo , Adenosina Trifosfatases/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Células Cultivadas , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Metformina/farmacologia , Mitocôndrias Hepáticas/metabolismo , Oxirredução/efeitos dos fármacos , Consumo de Oxigênio/efeitos dos fármacos , Ratos Wistar
19.
Clin Nutr ; 40(4): 1893-1896, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-32788089

RESUMO

Muscle protein synthesis (MPS) is a complex and finely-regulated mechanism that plays a key role in muscle homeostasis. Amino acid bioavailability is widely considered a major driver of MPS regulation via mTOR pathway activation. However, recent results suggest that amino acid bioavailability affects cellular energy status. Whatever the tool used to modulate energy status (amino acid depletion or mild mitochondrial uncoupling), a decrease in cellular energy status decreases MPS, without necessarily involving the mTOR pathway. Here we propose that energy status directly regulates one or several energy-consuming step(s) during MPS. This new paradigm modifies our vision of protein metabolism and raises prospects for new advances in therapeutics.


Assuntos
Metabolismo Energético/fisiologia , Proteínas Musculares/metabolismo , Biossíntese de Proteínas/fisiologia , Humanos
20.
Clin Nutr ; 40(3): 690-701, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33279311

RESUMO

BACKGROUND & AIMS: The year 2019 marked the centenary of the publication of the Harris and Benedict equations for estimation of energy expenditure. In October 2019 a Scientific Symposium was organized by the European Society for Clinical Nutrition and Metabolism (ESPEN) in Vienna, Austria, to celebrate this historical landmark, looking at what is currently known about the estimation and measurement of energy expenditure. METHODS: Current evidence was discussed during the symposium, including the scientific basis and clinical knowledge, and is summarized here to assist with the estimation and measurement of energy requirements that later translate into energy prescription. RESULTS: In most clinical settings, the majority of predictive equations have low to moderate performance, with the best generally reaching an accuracy of no more than 70%, and often lead to large errors in estimating the true needs of patients. Generally speaking, the addition of body composition measurements did not add to the accuracy of predictive equations. Indirect calorimetry is the most reliable method to measure energy expenditure and guide energy prescription, but carries inherent limitations, greatly restricting its use in real life clinical practice. CONCLUSIONS: While the limitations of predictive equations are clear, their use is still the mainstay in clinical practice. It is imperative to recognize specific patient populations for whom a specific equation should be preferred. When available, the use of indirect calorimetry is advised in a variety of clinical settings, aiming to avoid under-as well as overfeeding.


Assuntos
Ingestão de Energia , Metabolismo Energético , Política Nutricional , Necessidades Nutricionais , Idoso , Metabolismo Basal , Constituição Corporal , Peso Corporal , Calorimetria Indireta , Estado Terminal , Feminino , Humanos , Masculino , Neoplasias/fisiopatologia , Obesidade/fisiopatologia , Consumo de Oxigênio , Procedimentos Cirúrgicos Operatórios
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