Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 69
Filtrar
1.
World J Gastroenterol ; 22(2): 681-703, 2016 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-26811617

RESUMO

Obesity plays relevant pathophysiological role in the development of health problems, arising as result of complex interaction of genetic, nutritional, and metabolic factors. Due to the role of adipose tissue in lipid and glucose metabolism, and low grade inflammation, it is necessary to classify obesity on the basis of body fat composition and distribution, rather than the simply increase of body weight, and the Body Mass Index. The new term of adiposopathy (''sick fat'') clearly defines the pathogenic role of adipose tissue. Four phenotypes of obese individuals have been described: (1) normal weight obese (NWO); (2) metabolically obese normal weight; (3) metabolically healthy obese; and (4) metabolically unhealthy obese or "at risk" obese. Moreover, sarcopenic obesity has been related to all the phenotypes. The category of normal weight lean, represented by metabolically healthy normal weight has been classified to distinguish from NWO. It is crucial to recommend a bariatric surgery taking into account adiposopathy and sick fat that occurs with the expansion of fat mass, changing the inflammatory and metabolic profile of the patient. Body fat percentage and genetic polymorphism have to be evaluated to personalize the best bariatric surgery intervention.


Assuntos
Tecido Adiposo/fisiopatologia , Adiposidade , Cirurgia Bariátrica , Técnicas de Apoio para a Decisão , Obesidade/diagnóstico , Obesidade/cirurgia , Seleção de Pacientes , Adipocinas/metabolismo , Tecido Adiposo/metabolismo , Adiposidade/etnologia , Antropometria , Cirurgia Bariátrica/efeitos adversos , Peso Corporal , Metabolismo Energético , Feminino , Humanos , Mediadores da Inflamação/metabolismo , Masculino , Obesidade/classificação , Obesidade/fisiopatologia , Obesidade Metabolicamente Benigna/diagnóstico , Obesidade Metabolicamente Benigna/fisiopatologia , Obesidade Metabolicamente Benigna/cirurgia , Fenótipo , Valor Preditivo dos Testes , Fatores de Risco , Sarcopenia/diagnóstico , Sarcopenia/fisiopatologia , Fatores Sexuais , Terminologia como Assunto
2.
Expert Rev Neurother ; 13(8): 925-36, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23965166

RESUMO

Acetyl-L-carnitine (ALC) is a molecule derived from acetylation of carnitine in the mitochondria. Carnitine acetylation enables the function of CoA and facilitates elimination of oxidative products. Beyond this metabolic activity, ALC provides acetyl groups for acetylcholine synthesis, exerts a cholinergic effect and optimizes the balance of energy processes. Acetylcarnitine supplementation induces neuroprotective, neurotrophic and analgesic effects in the peripheral nervous system. In the recent studies, ALC, by acting as a donor of acetyl groups to NF-kb p65/RelA, enhanced the transcription of the GRM2 gene encoding the mGLU2 receptors, inducing long-term upregulation of the mGluR2, evidencing therefore that its long-term analgesic effects are dependent on epigenetic modifications. Several studies, including double-blind, placebo-controlled, parallel group studies and few open studies showed the effect of ALC in diseases characterized by neuropathies and neuropathic pain: the studies included diabetic neuropathy, HIV and antiretroviral therapy-induced neuropathies, neuropathies due to compression and chemotherapeutic agents. Double-blinded studies involved 1773 patients. Statistical evaluations evidenced reduction of pain, improvements of nerve function and trophism. In conclusion, ALC represents a consistent therapeutic option for peripheral neuropathies, and its complex effects, neurotrophic and analgesic, based on epigenetic mechanism, open new pathways in the study of peripheral nerve disease management.


Assuntos
Acetilcarnitina/farmacologia , Nootrópicos/farmacologia , Doenças do Sistema Nervoso Periférico/tratamento farmacológico , Doenças do Sistema Nervoso Periférico/fisiopatologia , Animais , Humanos , Neuralgia/tratamento farmacológico , Neuralgia/fisiopatologia
3.
J Natl Cancer Inst ; 105(7): 489-98, 2013 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-23486551

RESUMO

BACKGROUND: The metabolic alterations of cancer cells represent an opportunity for developing selective antineoplastic treatments. We investigated the therapeutic potential of ST1326, an inhibitor of carnitine-palmitoyl transferase 1A (CPT1A), the rate-limiting enzyme for fatty acid (FA) import into mitochondria. METHODS: ST1326 was tested on in vitro and in vivo models of Burkitt's lymphoma, in which c-myc, which drives cellular demand for FA metabolism, is highly overexpressed. We performed assays to evaluate the effect of ST1326 on proliferation, FA oxidation, and FA mitochondrial channeling in Raji cells. The therapeutic efficacy of ST1326 was tested by treating Eµ-myc mice (control: n = 29; treatment: n = 24 per group), an established model of c-myc-mediated lymphomagenesis. Experiments were performed on spleen-derived c-myc-overexpressing B cells to clarify the role of c-myc in conferring sensitivity to ST1326. Survival was evaluated with Kaplan-Meier analyses. All statistical tests were two-sided. RESULTS: ST1326 blocked both long- and short-chain FA oxidation and showed a strong cytotoxic effect on Burkitt's lymphoma cells (on Raji cells at 72 hours: half maximal inhibitory concentration = 8.6 µM). ST1326 treatment induced massive cytoplasmic lipid accumulation, impairment of proper mitochondrial FA channeling, and reduced availability of cytosolic acetyl coenzyme A, a fundamental substrate for de novo lipogenesis. Moreover, treatment with ST1326 in Eµ-myc transgenic mice prevented tumor formation (P = .01), by selectively impairing the growth of spleen-derived primary B cells overexpressing c-myc (wild-type cells + ST1326 vs. Eµ-myc cells + ST1326: 99.75% vs. 57.5%, difference = 42.25, 95% confidence interval of difference = 14% to 70%; P = .01). CONCLUSIONS: Our data indicate that it is possible to tackle c-myc-driven tumorigenesis by altering lipid metabolism and exploiting the neoplastic cell addiction to FA oxidation.


Assuntos
Anticarcinógenos/farmacologia , Apoptose/efeitos dos fármacos , Linfoma de Burkitt/enzimologia , Linfoma de Burkitt/prevenção & controle , Carnitina O-Palmitoiltransferase/antagonistas & inibidores , Carnitina O-Palmitoiltransferase/metabolismo , Carnitina/análogos & derivados , Metabolismo dos Lipídeos/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-myc/metabolismo , Animais , Linfócitos B/efeitos dos fármacos , Linfócitos B/metabolismo , Western Blotting , Linfoma de Burkitt/metabolismo , Linfoma de Burkitt/patologia , Carnitina/farmacologia , Carnitina Aciltransferases/antagonistas & inibidores , Carnitina Aciltransferases/metabolismo , Linhagem Celular Tumoral , Ácidos Graxos/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Estimativa de Kaplan-Meier , Camundongos , Oxirredução , Proteínas Proto-Oncogênicas c-myc/efeitos dos fármacos , Reação em Cadeia da Polimerase em Tempo Real , Resultado do Tratamento , Regulação para Cima
4.
J Gastrointest Cancer ; 43(3): 508-11, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21727995

RESUMO

PURPOSE: Fatty acid synthase is a common phenotype to various human cancers including those of prostate, colon, lung, endometrium, and stomach. Increased fatty acid synthase levels have been detected in serum from patients with breast and pancreatic cancer. In this study, serum levels of fatty acid synthase were measured in colorectal cancer patients at different stages of disease. METHODS: Consecutive 67 patients with colorectal cancer were enrolled in the study. Serum levels of fatty acid synthase were examined by ELISA test. The Kruskal-Wallis test and the χ (2) method for trend have been used to analyze data. RESULTS: Serum fatty acid synthase levels of patients belonging to three groups of stage disease are statistically different. The patients with stage III and IV have significantly higher serum levels of fatty acid synthase than patients with stage I-II. There is a positive trend in serum fatty acid synthase levels from stage I-II to stage III and IV of disease. CONCLUSIONS: Fatty acid synthase levels are associated with the stage of disease in patients with colorectal cancer.


Assuntos
Biomarcadores Tumorais/sangue , Neoplasias Colorretais/sangue , Neoplasias Colorretais/patologia , Ácido Graxo Sintase Tipo I/sangue , Neoplasias Colorretais/enzimologia , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Estadiamento de Neoplasias , Prognóstico
5.
J Proteomics ; 74(11): 2536-47, 2011 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-21672642

RESUMO

Oxidative stress has a central role in aging and in several age-linked diseases such as neurodegenerative diseases, diabetes and cancer. Mitochondria, as the main cellular source and target of reactive oxygen species (ROS) in aging, are recognized as very important players in the above reported diseases. Impaired mitochondrial oxidative phosphorylation has been reported in several aging tissues. Defective mitochondria are not only responsible of bioenergetically less efficient cells but also increase ROS production further contributing to tissues oxidative stress. Acetyl-L-carnitine (ALCAR) is a biomolecule able to limit age-linked mitochondrial decay in brain, liver, heart and skeletal muscles by increasing mitochondrial efficiency. Here the global changes induced by aging and by ALCAR supplementation to old rat on the mitochondrial proteome of rat liver has been analyzed by means of the two-dimensional polyacrylamide gel electrophoresis. Mass spectrometry has been used to identify the differentially expressed proteins. A significant age-related change occurred in 31 proteins involved in several metabolisms. ALCAR supplementation altered the levels of 26 proteins. In particular, ALCAR reversed the age-related alterations of 10 mitochondrial proteins relative to mitochondrial cristae morphology, to the oxidative phosphorylation and antioxidant systems, to urea cycle, to purine biosynthesis.


Assuntos
Acetilcarnitina/farmacologia , Envelhecimento/metabolismo , Mitocôndrias Hepáticas/metabolismo , Proteínas Mitocondriais/metabolismo , Proteoma/efeitos dos fármacos , Fatores Etários , Envelhecimento/fisiologia , Animais , Eletroforese em Gel Bidimensional , Masculino , Redes e Vias Metabólicas/efeitos dos fármacos , Mitocôndrias Hepáticas/efeitos dos fármacos , Proteínas Mitocondriais/análise , Proteínas Mitocondriais/efeitos dos fármacos , Fosforilação Oxidativa/efeitos dos fármacos , Proteoma/análise , Proteoma/metabolismo , Ratos , Ratos Endogâmicos F344 , Espécies Reativas de Oxigênio/metabolismo , Espectrometria de Massas por Ionização por Electrospray
6.
Aging Cell ; 9(4): 570-9, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20550520

RESUMO

In this work we report that carnitines, in particular acetyl-l-carnitine (ALC), are able to prolong the chronological aging of yeast cells during the stationary phase. Lifespan extension is significantly reduced in yca1 mutants as well in rho(0) strains, suggesting that the protective effects pass through the Yca1 caspase and mitochondrial functions. ALC can also prevent apoptosis in pro-apoptotic mutants, pointing to the importance of mitochondrial functions in regulating yeast apoptosis and aging. We also demonstrate that ALC attenuates mitochondrial fission in aged yeast cells, indicating a correlation between its protective effect and this process. Our findings suggest that ALC, used as therapeutic for stroke, myocardial infarction and neurodegenerative diseases, besides the well-known anti-oxidant effects, might exert protective effects also acting on mitochondrial morphology.


Assuntos
Acetilcarnitina/farmacologia , Apoptose/efeitos dos fármacos , Citoproteção/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/crescimento & desenvolvimento , Ácido Acético/farmacologia , Cafeína/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Modelos Biológicos , Mutação/genética , Estresse Oxidativo/efeitos dos fármacos , Consumo de Oxigênio/efeitos dos fármacos , Fenótipo , Ribonucleoproteína Nuclear Pequena U4-U6/genética , Saccharomyces cerevisiae/efeitos dos fármacos , Proteínas de Saccharomyces cerevisiae/genética , Fatores de Tempo
7.
Biofactors ; 36(1): 70-7, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20091799

RESUMO

The effect of acetyl-L-carnitine (ALCAR) supplementation to 3-month-old rats in normal-loading and unloading conditions has been here investigated by a combined morphological, biochemical and transcriptional approach to test whether ALCAR might cause a remodeling of the metabolic/contractile phenotype of soleus muscle. Morphological assessment demonstrated an increase of type I oxidative fiber content and cross-sectional area in ALCAR-treated animals both in normal-loading and in unloading conditions. ALCAR prevented loss of mitochondrial mass in unloaded animals whereas no ALCAR-dependent increase of mitochondrial mass occurred in normal-loaded muscle. Validated microarray analysis delineated an ALCAR-induced maintenance of a slow-oxidative expression program only in unloaded soleus muscle. Indeed, the muscle adjustment of the expression profile of factors underlying mitochondrial oxidative metabolism, protein turnover, fiber type differentiation and an adaptation of voltage-gated ion channel expression was distinguishable with respect to the loading status. This selectivity may suggest a key role of muscle loading status in the manifestation of ALCAR effects. The results extend to a broader level of biological informations the previous notion on ALCAR positive effect in rat soleus muscle during unloading and point to a role of ALCAR for the maintenance of its slow-oxidative fiber character.


Assuntos
Acetilcarnitina/farmacologia , Elevação dos Membros Posteriores/fisiologia , Músculo Esquelético/fisiologia , Animais , Citrato (si)-Sintase/biossíntese , Feminino , Perfilação da Expressão Gênica , Mitocôndrias Musculares/efeitos dos fármacos , Contração Muscular/efeitos dos fármacos , Fibras Musculares Esqueléticas/fisiologia , Músculo Esquelético/efeitos dos fármacos , Análise de Sequência com Séries de Oligonucleotídeos , Ratos , Ratos Wistar
8.
Biochim Biophys Acta ; 1787(7): 890-6, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19272351

RESUMO

Overoxidation and subsequent inactivation of Peroxiredoxin III (PrxIII), a mitochondrial H(2)O(2) scavenging enzyme, have been reported in oxidative stress conditions. No data are available in the literature about the presence of overoxidized forms of PrxIII in aged tissues. Liver mitochondria from 12-month-old rats and 28-month-old rats were here analyzed by two-dimensional gel electrophoresis. A spot corresponding to the native form of PrxIII was present in adult and old rats with the same volume, whereas an additional, more acidic spot, of the same molecular weight of the native form, accumulated only in old rats. The acidic spot was identified, by MALDI-MS analysis, as a form of PrxIII bearing the cysteine of the catalytic site overoxidized to sulphonic acid. This modified PrxIII form corresponds to the irreversibly inactivated enzyme, here reported, for the first time, in aging. Three groups of 28-month-old rats treated with acetyl-l-carnitine were also examined. Reduced accumulation of the overoxidized PrxIII form was found in all ALCAR-treated groups.


Assuntos
Mitocôndrias Hepáticas/metabolismo , Peroxirredoxinas/química , Peroxirredoxinas/metabolismo , Acetilcarnitina/farmacologia , Envelhecimento , Animais , Cisteína/química , Cisteína/metabolismo , Eletroforese em Gel Bidimensional , Masculino , Espectrometria de Massas , Peso Molecular , Nootrópicos/farmacologia , Oxirredução , Peroxirredoxinas/genética , Ratos , Ratos Endogâmicos F344 , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
9.
Clin Neuropharmacol ; 32(1): 35-40, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-18978503

RESUMO

INTRODUCTION: This study was designed to determine the short-term effect of acetyl-l-carnitine (ALC) on symptoms of withdrawal in opiate-dependent subjects and animals and, in particular, on pain, given the efficacy of ALC in other typologies of pain. The study consists of 2 branches: a clinical study and a preclinical one, both with a randomized placebo-controlled design. METHODS: Thirty subjects meeting clinical criteria for methadone dependence were consecutively recruited and treated with ALC 2 g/d or placebo for a 3-week detoxification period. Withdrawal symptoms and pain were evaluated through the Short Opiate Withdrawal Syndrome scale, and the Huskisson's analogue scale for pain. In the preclinical study, mice previously received a pretreatment (saline solution or morphine), and subsequently, each group was randomly divided in 4 subgroups that received a treatment of saline, methadone, ALC, or amitriptyline, respectively. Hot plate test and Writhing test were used to evaluate pain intensity. RESULTS: Average Short Opiate Withdrawal Syndrome total scores during the first 5 days of treatment resulted significantly higher in controls than in the ALC group (P < 0.05). Pain scores in the Huskisson's analogue scale were considerably lower in the group of patients taking ALC than in the control group after 1 week of ALC treatment until the end of the study. Results of the preclinical study show that the administration of methadone for 7 days in morphine-tolerant mice did not produce any modification of the pain threshold. By contrast, the 7-day coadministration of methadone and ALC in morphine-tolerant mice induced an analgesic effect evaluated 3 hours after the last injection. DISCUSSION: Acetyl-L-carnitine acted as an effective antihyperalgesic agent for relieving opiate-withdrawal hyperalgesia in animals and displayed clinical efficacy on other withdrawal symptoms such as muscular tension, muscular cramps, and insomnia. Considering its tolerability, the excellent side effect profile, the absence of significant interactions, and the lack of abuse potential, ALC can be considered as a useful pharmacological adjunct in the treatment of opiate withdrawal.


Assuntos
Acetilcarnitina/uso terapêutico , Analgésicos Opioides/efeitos adversos , Metadona/efeitos adversos , Nootrópicos/uso terapêutico , Dor/tratamento farmacológico , Dor/etiologia , Síndrome de Abstinência a Substâncias/complicações , Adulto , Amitriptilina/uso terapêutico , Analgésicos não Narcóticos/uso terapêutico , Analgésicos Opioides/administração & dosagem , Animais , Modelos Animais de Doenças , Esquema de Medicação , Feminino , Humanos , Masculino , Metadona/administração & dosagem , Camundongos , Morfina/administração & dosagem , Transtornos Relacionados ao Uso de Opioides/complicações , Transtornos Relacionados ao Uso de Opioides/tratamento farmacológico , Medição da Dor , Fatores de Tempo , Adulto Jovem
10.
J Neurosci Res ; 87(1): 200-7, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18709658

RESUMO

Several pathologies related to nervous tissue alterations are characterized by a chronic pain syndrome defined by persistent or paroxysmal pain independent or dependent on a stimulus. Pathophysiological mechanisms related to neuropathic disease are associated with mitochondrial dysfunctions that lead to an activation of the apoptotic cascade. In a model of peripheral neuropathy obtained by the loose ligation of the rat sciatic nerve, acetyl-L-Carnitine (ALCAR; 100 mg/kg intraperitoneally [i.p.] twice daily for 14 days) was able to reduce hyperalgesia and apoptosis. In the present study, different mechanisms for the analgesic and the antineuropathic effect of ALCAR are described. The muscarinic blocker atropine (5 mg/kg i.p.) injected simultaneously with ALCAR did not antagonize the ALCAR antihyperalgesic effect on the paw-pressure test but significantly reduced the analgesic effect of ALCAR. Conversely, the antineuropathic effect of ALCAR was prevented by cotreatment with the nicotinic antagonist mecamylamine (2 mg/kg i.p. twice daily for 14 days). A pharmacological silencing of the nicotinic receptors significantly reduced the X-linked inhibitor of apoptosis protein-related protective effect of ALCAR on the apoptosis induced by ligation of the sciatic nerve. Taken together, these data highlight the relevance of nicotinic modulation in neuropathy treatment.


Assuntos
Acetilcarnitina/uso terapêutico , Apoptose/efeitos dos fármacos , Fármacos Neuroprotetores/uso terapêutico , Receptores Nicotínicos/metabolismo , Ciática , Animais , Atropina/farmacologia , Caspase 3/metabolismo , Citocromos c/metabolismo , Modelos Animais de Doenças , Marcação In Situ das Extremidades Cortadas/métodos , Masculino , Mecamilamina/farmacologia , Antagonistas Muscarínicos/farmacologia , Antagonistas Nicotínicos/farmacologia , Medição da Dor/efeitos dos fármacos , Medição da Dor/métodos , Poli(ADP-Ribose) Polimerase-1 , Poli(ADP-Ribose) Polimerases/metabolismo , Ratos , Ratos Sprague-Dawley , Ciática/tratamento farmacológico , Ciática/patologia , Ciática/fisiopatologia , Fatores de Tempo , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/metabolismo
11.
Eur J Pharmacol ; 597(1-3): 51-6, 2008 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-18801359

RESUMO

Alzheimer Disease is the most common chronic neurodegenerative disorder associated with aging. Nevertheless, its pharmacological therapy is still an unresolved issue. In double-blind controlled studies, acetyl-L-carnitine (ALC) demonstrated beneficial effects on Alzheimer's disease. However, the mechanisms behind its neuroprotective ability remain to be fully established. In this study, the effect of acetyl-L-carnitine on amyloid precursor protein (APP) metabolism was investigated by in vitro models, both in a neuroblastoma cell line and in primary hippocampal cultures. We found that ALC treatment stimulates alpha-secretase activity and physiological APP metabolism. In particular, ALC favors the delivery of ADAM10 (a disintegrin and metalloproteinase 10, the most accredited candidate for alpha-secretase) to the post-synaptic compartment, and consequently positively modulates its enzymatic activity towards APP. Our findings suggest that the benefits of ALC reported in previous clinical studies are underscored by the specific biological mechanism of this compound on APP metabolism. In fact, ALC can directly influence the primary event in Alzheimer's disease pathogenesis, i.e. the Amyloid beta cascade, promoting alpha-secretase activity and directly affecting the release of the non amyloidogenic metabolite.


Assuntos
Acetilcarnitina/farmacologia , Precursor de Proteína beta-Amiloide/metabolismo , Hipocampo/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Proteínas ADAM/metabolismo , Secretases da Proteína Precursora do Amiloide/metabolismo , Animais , Linhagem Celular Tumoral , Células Cultivadas , Relação Dose-Resposta a Droga , Hipocampo/embriologia , Hipocampo/enzimologia , Hipocampo/metabolismo , Humanos , Neurônios/enzimologia , Neurônios/metabolismo , Transporte Proteico , Ratos , Fatores de Tempo
12.
Obesity (Silver Spring) ; 16(8): 1831-7, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18535540

RESUMO

BACKGROUND: Hyperprolactinemia is associated with obesity. Furthermore, in human adipose tissue cultured in vitro, prolactin (PRL) inhibited lipoprotein lipase (LPL) activity via functional PRL receptors. OBJECTIVE: To study PRL and insulin ultradian rhythm and subcutaneous adipose tissue LPL mRNA and protein expressions in severely obese women before and after malabsorptive bariatric surgery. METHODS AND PROCEDURES: Seven severely obese, fertile women were studied twice, once before and the second time 1 year after bilio-pancreatic diversion (BPD), when the weight was stable for at least 3 months. Metabolizable energy intake and 24-h energy expenditure (EE) were measured. Fourier and PULSEFIT analyses were applied to 24-h hormonal time-series to study daily fluctuations and hormonal clearance. Insulin sensitivity was assessed by euglycemic-hyperinsulinemic clamp. Quantitative-competitive reverse transcriptase-PCR and western blot analysis were used to measure LPL gene expression. RESULTS: Spontaneous 24-h PRL secretion was significantly reduced after BPD (mean-daily release, 128.4 +/- 28.1 microg/l vs. 67.2 +/- 9.2 microg/l distribution volume (Vd/l.24 h), P = 0.02); insulin secretion also was significantly reduced (499.9 +/- 204.0 microg/Vd/l.24 h vs. 85.6 +/- 21.0 microg/Vd/l.24 h, P = 0.0001). Metabolizable energy/kg(FFM) did not change significantly after BPD. Twenty-four-hour EE, but not 24-h EE/FFM, was significantly decreased after BPD (P < 0.05). Insulin sensitivity significantly (P < 0.0001) increased after BPD from 21.41 +/- 1.92 to 68.62 +/- 5.03 micromol/kg(FFM)/min. LPL mRNA concentration (from 42.63 +/- 4.21% to 19.00 +/- 2.74% of cyclophilin mRNA, P = 0.001) as well as LPL protein level (from 8.94 +/- 2.73 to 3.16 +/- 1.05 as ratios of protein of interest vs. housekeeping protein, P = 0.038) significantly decreased after BPD. The major determinant of PRL secretion was insulin secretion, whereas the best predictors of LPL expression were insulin and PRL secretion rates. DISCUSSION: The restriction of lipid metabolizable energy rather than weight loss seems to be responsible for both reduction in PRL circulating levels and normalization of its secretion rhythm after bariatric surgery. Furthermore, the reduced adipose tissue LPL expression, being significantly correlated with the decrease in insulin and PRL, suggests a role of hyperinsulinemia and hyperprolactinemia in inducing and sustaining obesity.


Assuntos
Tecido Adiposo/enzimologia , Ritmo Circadiano/fisiologia , Insulina/metabolismo , Lipase Lipoproteica/metabolismo , Obesidade Mórbida/metabolismo , Obesidade Mórbida/cirurgia , Prolactina/metabolismo , Tecido Adiposo/patologia , Adulto , Cirurgia Bariátrica , Biópsia , Metabolismo Energético/fisiologia , Estradiol/sangue , Feminino , Hormônio Foliculoestimulante/sangue , Seguimentos , Análise de Fourier , Humanos , Insulina/sangue , Resistência à Insulina/fisiologia , Secreção de Insulina , Lipase Lipoproteica/genética , Prolactina/sangue , RNA Mensageiro/metabolismo , Globulina de Ligação a Hormônio Sexual/metabolismo
13.
J Biochem Mol Toxicol ; 22(1): 8-14, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18273902

RESUMO

The interaction of mildronate [3-(2,2,2-trimethylhydrazine) propionate] with the purified mitochondrial carnitine/acylcarnitine transporter reconstituted in liposomes has been studied. Mildronate, externally added to the proteoliposomes, strongly inhibited the carnitine/carnitine antiport catalyzed by the reconstituted transporter with an IC(50) of 560 muM. A kinetic analysis revealed that the inhibition is completely competitive, that is, mildronate interacts with the substrate-binding site. The half-saturation constant of the transporter for external mildronate (K(i)) is 530 muM. Carnitine/mildronate antiport has been measured as [(3)H]carnitine uptake into proteoliposomes containing internal mildronate or as [(3)H]carnitine efflux from proteoliposomes in the presence of external mildronate, indicating that mildronate is transported by the carnitine/acylcarnitine transporter and that the inhibition observed was due to the transport of mildronate in the place of carnitine. The intraliposomal half-saturation constant for mildronate transport (K(m)) has been determined. Its value, 18 mM, is much higher than the external half-saturation constant (K(i)) in agreement with the asymmetric properties of the transporter. In vivo, the antiport reaction between cytosolic (administered) mildronate and matrix carnitine may cause intramitochondrial carnitine depletion. This effect, together with the inhibition of the physiological transport, will lead to impairment of fatty acid utilization.


Assuntos
Carnitina/análogos & derivados , Carnitina/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Metilidrazinas/metabolismo , Mitocôndrias Hepáticas/metabolismo , Animais , Antiporters/antagonistas & inibidores , Transporte Biológico/efeitos dos fármacos , Carnitina/química , Relação Dose-Resposta a Droga , Cinética , Lipossomos , Metilidrazinas/farmacologia , Mitocôndrias Hepáticas/efeitos dos fármacos , Ligação Proteica , Ratos , Fatores de Tempo
14.
Am J Med Genet A ; 146A(7): 803-12, 2008 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-18286595

RESUMO

Attention deficit hyperactivity disorder (ADHD) is a frequent behavioral problem in young boys with fragile X syndrome (FXS), and its treatment is critical for improving social ability. The short-term efficacy of stimulant medications like methylphenidate (MPH) is well established in children with ADHD. FXS boys treated with MPH have improved attention span and socialization skills; however their mood becomes unstable at higher doses. Therefore, alternative pharmacological treatment of ADHD symptoms is desirable. A recent study showed that carnitine has a beneficial effect on the hyperactive-impulsive behavior in boys with ADHD without side effects. Our previous placebo-controlled trial indicated that L-acetylcarnitine (LAC) reduces hyperactivity in FXS boys. The objective of this study was to determine the efficacy of LAC in a larger sample of FXS boys with ADHD. The study design was randomized, double blind placebo controlled, parallel, and multicenter (with eight centers involved in Italy, France, and Spain). Sixty-three FXS males with ADHD (aged 6-13 years) were enrolled; 7 patients dropped out, 56 completed the one-year treatment, and 51 were included in the statistical analysis. Both groups improved their behavior, showing that psychosocial intervention has a significant therapeutic effect. However, we observed a stronger reduction of hyperactivity and improvement of social behavior in patients treated with LAC, compared with the placebo group, as determined by the Conners' Global Index Parents and the Vineland Adaptive Behavior Scale. Our results show that LAC (20-50 mg/kg/day) represents a safe alternative to the use of stimulant drugs for the treatment of ADHD in FXS children.


Assuntos
Acetilcarnitina/uso terapêutico , Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Síndrome do Cromossomo X Frágil/complicações , Adolescente , Transtorno do Deficit de Atenção com Hiperatividade/complicações , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Criança , Método Duplo-Cego , Síndrome do Cromossomo X Frágil/genética , Síndrome do Cromossomo X Frágil/psicologia , Humanos , Masculino , Testes Neuropsicológicos , Placebos , Resultado do Tratamento
15.
Diabetes Care ; 31(1): 3-8, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17959863

RESUMO

OBJECTIVE: To clarify the pathogenesis of diabetes associated with mutations of the hemochromatosis (HFE) gene, 17 carriers, 9 normal glucose tolerant (NGT) and 8 diabetic, were evaluated in an interventional trial. RESEARCH DESIGN AND METHODS: At enrollment and after a 2-year bloodletting period, euglycemic-hyperinsulinemic clamp, oral glucose tolerance test (OGTT), liver histology (nonalcoholic fatty liver disease activity score [NAS]), and liver iron content (LIC) were assessed. RESULTS: NGT subjects had significantly higher baseline insulin sensitivity (P

Assuntos
Antígenos de Histocompatibilidade Classe I/genética , Insulina/metabolismo , Ferro/metabolismo , Fígado/metabolismo , Proteínas de Membrana/genética , Mutação , Flebotomia , Adulto , Substituição de Aminoácidos , Portador Sadio , Triagem de Portadores Genéticos , Hemocromatose/genética , Proteína da Hemocromatose , Homozigoto , Humanos , Secreção de Insulina , Masculino , Pessoa de Meia-Idade , Seleção de Pacientes
16.
Nat Rev Neurosci ; 8(10): 766-75, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17882254

RESUMO

At the end of the 1980s, it was clearly demonstrated that cells produce nitric oxide and that this gaseous molecule is involved in the regulation of the cardiovascular, immune and nervous systems, rather than simply being a toxic pollutant. In the CNS, nitric oxide has an array of functions, such as the regulation of synaptic plasticity, the sleep-wake cycle and hormone secretion. Particularly interesting is the role of nitric oxide as a Janus molecule in the cell death or survival mechanisms in brain cells. In fact, physiological amounts of this gas are neuroprotective, whereas higher concentrations are clearly neurotoxic.


Assuntos
Sistema Nervoso Central/fisiologia , Doenças Neurodegenerativas/metabolismo , Fármacos Neuroprotetores/metabolismo , Óxido Nítrico/fisiologia , Animais , Sistema Nervoso Central/patologia , Humanos , Doenças Neurodegenerativas/prevenção & controle , Fármacos Neuroprotetores/uso terapêutico , Síndromes Neurotóxicas/metabolismo , Síndromes Neurotóxicas/prevenção & controle , Óxido Nítrico/uso terapêutico , Óxido Nítrico/toxicidade
17.
Obesity (Silver Spring) ; 15(8): 2012-8, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17712119

RESUMO

OBJECTIVE: The objective was to evaluate ghrelin and growth hormone (GH) interactions and responses to a growth hormone-releasing hormone (GHRH)/arginine test in severe obesity before and after surgically-induced weight loss. RESEARCH METHODS AND PROCEDURES: Our study population included 11 severely obese women 39 +/- 12 years of age, with a mean BMI of 48.6 +/- 2.4 kg/m2, re-studied in a phase of stabilized body weight, with a BMI of 33.4 +/- 1.2 kg/m2, 18 months after having successfully undergone biliopancreatic diversion (BPD). A GHRH/arginine test was performed before and 18 months after BPD to evaluate ghrelin and GH interactions. Active ghrelin, measured by radioimmunoassay (RIA), and GH, measured by chemiluminescence assay, were assayed before and after the GHRH/arginine test. RESULTS: Fasting serum GH levels and GH area under the curve (AUC) significantly increased from 0.2 +/- 0.05 ng/mL to 1 +/- 0.3 ng/mL (p < 0.05) and from 514.76 +/- 98.7 ng/mL for 120 minutes to 1957.3 +/- 665.1 ng/mL for 120 minutes after bariatric surgery (p < 0.05), respectively. Although no significant change in fasting ghrelin levels was observed (573 +/- 77.9 before BPD vs. 574.1 +/- 32.7 after BPD), ghrelin AUC significantly increased from -3253.9 +/- 2180.9 pg/mL for 120 minutes to 1142.3 +/- 916.4 pg/mL for 120 minutes after BPD (p < 0.05). Fasting serum insulin-like growth factor (IGF)-1 concentration did not change significantly (133.6 +/- 9.9 ng/mL before vs. 153.3 +/- 25.2 ng/mL after BPD). DISCUSSION: Our study demonstrates that the mechanisms involved in ghrelin and GH secretion after the secretagogue stimulus (GHRH/arginine) are consistent with patterns observed in other populations.


Assuntos
Desvio Biliopancreático/métodos , Hormônio do Crescimento/metabolismo , Obesidade Mórbida/fisiopatologia , Obesidade Mórbida/cirurgia , Hormônios Peptídicos/metabolismo , Redução de Peso/fisiologia , Adulto , Arginina/administração & dosagem , Glicemia/metabolismo , Feminino , Grelina , Hormônio do Crescimento/sangue , Hormônio Liberador de Hormônio do Crescimento/administração & dosagem , Humanos , Insulina/sangue , Fator de Crescimento Insulin-Like I/metabolismo , Leptina/sangue , Pessoa de Meia-Idade , Obesidade Mórbida/sangue , Hormônios Peptídicos/sangue
18.
Diabetes Care ; 30(6): 1494-500, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17526821

RESUMO

OBJECTIVE: Obesity, insulin resistance, and weight loss have been associated with changes in hypothalamic-pituitary-adrenal (HPA) axis. So far, no conclusive data relating to this association are available. In this study, we aim to investigate the effects of massive weight loss on cortisol suppressibility, cortisol-binding globulin (CBG), and free cortisol index (FCI) in formerly obese women. RESEARCH DESIGN AND METHODS: Ten glucose-normotolerant, fertile, obese women (BMI >40 kg/m2, aged 38.66 +/- 13.35 years) were studied before and 2 years after biliopancreatic diversion (BPD) when stable weight was achieved and were compared with age-matched healthy volunteers. Cortisol suppression was evaluated by a 4-mg intravenous dexamethasone suppression test (DEX-ST). FCI was calculated as the cortisol-to-CBG ratio. Insulin sensitivity was measured by an euglycemic-hyperinsulinemic clamp, and insulin secretion was measured by a C-peptide deconvolution method. RESULTS: No difference was found in cortisol suppression after DEX-ST before or after weight loss. A decrease in ACTH was significantly greater in control subjects than in obese (P = 0.05) and postobese women (P < or = 0.01) as was the decrease in dehydroepiandrosterone (P < or = 0.05 and P < or = 0.01, respectively). CBG decreased from 51.50 +/- 12.76 to 34.33 +/- 7.24 mg/l (P < or = 0.01) following BPD. FCI increased from 11.15 +/- 2.85 to 18.16 +/- 6.82 (P < or = 0.05). Insulin secretion decreased (52.04 +/- 16.71 vs. 30.62 +/- 16.32 nmol/m(-2); P < or = 0.05), and insulin sensitivity increased by 163% (P < or = 0.0001). Serum CBG was related to BMI (r(0) = 0.708; P = 0.0001), body weight (r(0) = 0.643; P = 0.0001), body fat percent (r(0) = 0.462; P = 0.001), C-reactive protein (r(0) = 0.619; P = 0.004), and leptin (r(0) = 0.579; P = 0.007) and negatively to M value (r(0) = -0.603; P = 0.005). CONCLUSIONS: After massive weight loss in morbidly obese subjects, an increase of free cortisol was associated with a simultaneous decrease in CBG levels, which might be an adaptive phenomenon relating to environmental changes. This topic, not addressed before, adds new insight into the complex mechanisms linking HPA activity to obesity.


Assuntos
Cirurgia Bariátrica , Hidrocortisona/sangue , Obesidade/sangue , Transcortina/metabolismo , Redução de Peso , Tecido Adiposo/anatomia & histologia , Adulto , Glicemia/metabolismo , Pressão Sanguínea , Tamanho Corporal , Colesterol/sangue , Dexametasona , Hormônio do Crescimento Humano/sangue , Humanos , Leptina/sangue , Pessoa de Meia-Idade , Obesidade/cirurgia , Valores de Referência
20.
Neurochem Res ; 32(4-5): 555-67, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-16915364

RESUMO

Since its definition Alzheimer's disease has been at the centre of consideration for neurologists, psychiatrists, and pathologists. With John P. Blass it has been disclosed a different approach Alzheimer's disease neurodegeneration understanding not only by the means of neurochemistry but also biochemistry opening new scenarios in the direction of a metabolic system degeneration. Nowadays, the understanding of the role of cholesterol, insulin, and adipokines among the others in Alzheimer's disease etiopathogenesis is clarifying approaches valuable not only in preventing the disease but also for its therapy.


Assuntos
Doença de Alzheimer/história , Doença de Alzheimer/metabolismo , Química Encefálica/fisiologia , Doenças Metabólicas/metabolismo , Adiponectina/metabolismo , Doença de Alzheimer/psicologia , Apolipoproteínas E/metabolismo , Colesterol/metabolismo , Feminino , Grelina , História do Século XX , Humanos , Insulina/metabolismo , Fator de Crescimento Insulin-Like I/metabolismo , Leptina/metabolismo , Pessoa de Meia-Idade , Hormônios Peptídicos/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...