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1.
Ann Ig ; 34(4): 421-424, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35700031

Asunto(s)
Salud Pública , Humanos
2.
Ann Ig ; 27(4): 609-12, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26241105

RESUMEN

On this occasion I am very grateful to the Academic Authorities for having asked me to illustrate the life of Giovanni Berlinguer as a Researcher, a Professor and a Doctor of Public Health. I will try to fulfill this duty, perhaps with some reservations, because I find it almost impossible to think of Giovanni as a researcher and a professor separately from his complex personality and his role as a politician and a brilliant and prolific writer. This is because Giovanni was an inextricable combination of all these roles, which cannot be described separately.


Asunto(s)
Libros/historia , Docentes Médicos/historia , Política , Salud Pública/historia , Bioética/historia , Unión Europea , Historia del Siglo XX , Historia del Siglo XXI , Humanos , Italia , Liderazgo , Parasitología/historia , Filosofía Médica/historia , Medicina Preventiva/historia , Naciones Unidas/historia , Organización Mundial de la Salud/historia
3.
IJTLD Open ; 1(1): 11-19, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38799089

RESUMEN

BACKGROUND: TB preventive treatment (TPT) reduces morbidity and mortality among people living with HIV (PLHIV). Despite the successful scale-up of TPT in Malawi, monitoring and evaluation have been suboptimal. We utilized the Malawi Population-Based HIV Impact Assessment (MPHIA) 2020-2021 survey data to estimate TPT uptake and completion among self-reported HIV-positive persons. METHODS: We estimated the proportion of HIV-positive respondents who had ever undergone TPT, and determined the percentage of those currently on TPT who had completed more than 6 months of treatment. Bivariate and multivariable logistic regression were performed to calculate the odds ratios for factors associated with ever-taking TPT. All variables were self-reported, and the analysis was weighted and accounted for in the survey design. RESULTS: Of the HIV+ respondents, 38.8% (95% CI 36.4-41.3) had ever taken TPT. The adjusted odds of ever taking TPT were 8.0 and 5.2 times as high in the Central and Southern regions, respectively, compared to the Northern region; 1.9 times higher among those in the highest wealth quintile, and 2.1 times higher for those on antiretroviral therapy >10 years. Of those currently taking TPT, 56.2% completed >6 months of TPT. CONCLUSION: These results suggest low TPT uptake and >6 months' completion rates among self-reported HIV+ persons. Initiatives to create demand and strengthen adherence would improve TPT uptake.


CONTEXTE: Le traitement préventif de la TB (TPT) réduit la morbidité et la mortalité chez les personnes vivant avec le VIH (PVVIH). Malgré l'extension réussie du TPT au Malawi, le suivi et l'évaluation n'ont pas été optimaux. Nous avons utilisé les données de l'enquête MPHIA (Malawi Population-Based HIV Impact Assessment) 2020­2021 pour estimer l'adoption et l'achèvement du TPT parmi les personnes se déclarant séropositives. MÉTHODES: Nous avons estimé la proportion de répondants séropositifs qui avaient déjà subi un TPT et déterminé le pourcentage de ceux qui sont actuellement sous TPT et qui ont terminé plus de 6 mois de traitement. Une régression logistique bivariée et multivariable a été effectuée pour calculer les rapports de cotes des facteurs associés au fait d'avoir déjà pris un TPT. Toutes les variables étaient autodéclarées et l'analyse a été pondérée et prise en compte dans la conception de l'enquête. RÉSULTATS: Parmi les répondants séropositifs, 38,8% (IC 95% 36,4­41,3) avaient déjà pris du TPT. Les probabilités ajustées de prise de TPT étaient 8,0 et 5,2 fois plus élevées dans les régions du centre et du sud, respectivement, que dans la région du nord ; 1,9 fois plus élevées chez les personnes appartenant au quintile de richesse le plus élevé, et 2,1 fois plus élevées chez les personnes suivant une thérapie antirétrovirale depuis plus de 10 ans. Parmi ceux qui prennent actuellement un TPT, 56,2% ont terminé >6 mois de TPT. CONCLUSION: Ces résultats suggèrent un faible taux d'utilisation du TPT et des taux d'achèvement de >6 mois parmi les personnes déclarées séropositives. Des initiatives visant à créer une demande et à renforcer l'adhésion permettraient d'améliorer l'utilisation du TPT.

4.
Diabetologia ; 54(2): 339-49, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-20972533

RESUMEN

AIMS/HYPOTHESIS: Metformin is widely used for the treatment of type 2 diabetes. Although it reduces hepatic glucose production, clinical studies show that metformin may reduce plasma dipeptidyl peptidase-4 activity and increase circulating levels of glucagon-like peptide 1 (GLP-1). We examined whether metformin exerts glucoregulatory actions via modulation of the incretin axis. METHODS: Metformin action was assessed in Glp1r(-/-), Gipr(-/-), Glp1r:Gipr(-/-), Pparα (also known as Ppara)(-/-) and hyperglycaemic obese wild-type mice with or without the GLP-1 receptor (GLP1R) antagonist exendin(9-39). Experimental endpoints included glucose tolerance, plasma insulin levels, gastric emptying and food intake. Incretin receptor expression was assessed in isolated islets from metformin-treated wild-type and Pparα(-/-) mice, and in INS-1 832/3 beta cells with or without peroxisome proliferator-activated receptor (PPAR)-α or AMP-activated protein kinase (AMPK) antagonists. RESULTS: In wild-type mice, metformin acutely increased plasma levels of GLP-1, but not those of gastric inhibitory polypeptide or peptide YY; it also improved oral glucose tolerance and reduced gastric emptying. Metformin significantly improved oral glucose tolerance despite loss of incretin action in Glp1r(-/-), Gipr(-/-) and Glp1r(-/-) :Gipr(-/-) mice, and in wild-type mice fed a high-fat diet and treated with exendin(9-39). Levels of mRNA transcripts for Glp1r, Gipr and Pparα were significantly increased in islets from metformin-treated mice. Metformin directly increased Glp1r expression in INS-1 beta cells via a PPAR-α-dependent, AMPK-independent mechanism. Metformin failed to induce incretin receptor gene expression in islets from Pparα(-/-) mice. CONCLUSIONS/INTERPRETATION: As metformin modulates multiple components of the incretin axis, and enhances expression of the Glp1r and related insulinotropic islet receptors through a mechanism requiring PPAR-α, metformin may be mechanistically well suited for combination with incretin-based therapies.


Asunto(s)
Hipoglucemiantes/farmacología , Metformina/farmacología , PPAR alfa/metabolismo , Receptores de la Hormona Gastrointestinal/metabolismo , Animales , Línea Celular , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Dipeptidil Peptidasa 4/sangre , Ingestión de Alimentos/efectos de los fármacos , Polipéptido Inhibidor Gástrico/sangre , Péptido 1 Similar al Glucagón/sangre , Receptor del Péptido 1 Similar al Glucagón , Hipoglucemiantes/uso terapéutico , Masculino , Metformina/uso terapéutico , Ratones , Ratones Endogámicos C57BL , Ratones Mutantes , PPAR alfa/genética , Fragmentos de Péptidos/uso terapéutico , Receptores de la Hormona Gastrointestinal/genética , Receptores de Glucagón/antagonistas & inhibidores , Receptores de Glucagón/sangre , Transducción de Señal/efectos de los fármacos
5.
Ann Ig ; 22(1): 19-27, 2010.
Artículo en Italiano | MEDLINE | ID: mdl-20476660

RESUMEN

In recent years, physical-chemical, chemical and microbiological testing systems to water's control was matched by the use of "biomarkers" such as algae, nematodes, Anellidi, Porifera, molluscs and arthropods (crustaceans), although these are phylogenetically distant from humans and they differ in methods of recruitment, toxico-kinetics and metabolism of xenobiotics. That is why today the predatory fishes (tuna, mackerel, sea bream, sea bass and swordfish) are among the most widely used in biomonitoring studies. In particular Sparus aurata and Dicentrarchus labrax (sea bream and sea bass) are appropriate in warning of environmental pollution. Moreover since the two species are precious and particularly present in food, they could represent a potential vehicle for the transport of contaminants to humans. To this end, the aim of this note, part of a complex research project launched in line with the provisions of the ministry for the environment, land and sea, is to evaluate the quality of coastal waters by using of Sparus aurata and Dicentrarchus labrax. The results obtained show that the area concerned, at present, is not affected by serious pollution processes, as the human pressure is highlighted by the presence of phenols in sea water and heavy metals (Cd and Hg) in the bioindicators. The detection of these toxic elements in fish species, could also not be directly attributable to any condition of impairment of the environment. However given the accumulation of these contaminants in the parts are edible, the consumption of fish could be a source of exposure particularly for those most exposed to health risks (children, elderly, sick and pregnant women).


Asunto(s)
Lubina , Monitoreo del Ambiente/métodos , Dorada , Agua de Mar , Contaminación del Agua , Animales , Italia
6.
J Prev Med Hyg ; 47(2): 49-55, 2006 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17066903

RESUMEN

INTRODUCTION: The aims of this study are to assess the quality of the coastal waters of central-northern Sardinia through data from a monitoring network and to outline maps and experimental models of environmental risk correlated to the presence of chemical and microbiological contaminants. The area studied is the coast between Capo Falcone and the mouth of the river Coghinas, in the northwestern part of the island. METHODS: In a first phase, 7 sampling stations of sea water and 1 sampling station of bivalve molluscs (Mytilus galloprovincialis Lam.) were identified. For each transept 3 different collection points at respectively 500, 1000, and 3000 meters from the coast for a total 21 sampling sites were identified. In a second phase, another 7 transepts were identified, 2 of which on the island of Asinara. RESULTS: As regards the microbiological monitoring of the sea water, very low concentrations of Total coliforms, Faecal coliforms and Faecal Streptococci were found and no Salmonella were isolated. Chemical analysis of the waters showed a high constant presence of phenols. In the bivalves we found rather high concentrations of Faecal coliforms without any clear seasonal variation, while no Salmonella was isolated in any of the examined samples. DISCUSSION: The results show that the considered area is not affected by serious pollution processes, thus allowing to express a completely satisfactory judgement on its state of health. However anthropic pressure in the considered territory is testified by the presence in the water of high concentrations of phenols. CONCLUSIONS: The results point out to the necessity of targeted and rational preventive action by means of control and protection measures for environmental ecosytems.


Asunto(s)
Enterobacteriaceae/aislamiento & purificación , Agua de Mar/química , Agua de Mar/microbiología , Contaminación del Agua/análisis , Animales , Monitoreo del Ambiente , Italia , Mytilus/microbiología , Fenoles/análisis , Microbiología del Agua
7.
Ann Ig ; 17(3): 209-17, 2005.
Artículo en Italiano | MEDLINE | ID: mdl-16041923

RESUMEN

The study reports the prevalence of cigarette smoking among 11401 high school Sardinian students. The prevalence of smokers (40.2%) significantly differs between gender (41.1% males and 38.4% females). Males have an early initiation of smoking with an evident addictive effect by age. 54.3% are daily smokers and 21.4% smoke 15 or more cigarettes per day. More than 50% smoke to look grown-up and to be accepted by the group. Besides age (OR=1.10; 95%CI: 1.06-1.15), other factors are associated with smoke: low education level of father (OR=1.08; 95%CI: 1.02-1.15), no maternal support (OR = 1.73; 95%CI: 1.17-2.54), to have at least one smoker cohabitant (OR=1.66; 95%CI: 1.54-1.80) and alcohol drinking (OR=3.46; 95%CI: 3.04-3.93). The smokers' knowledge on smoke topics significantly differ from non smokers. Our results suggest the need of community preventive interventions, diversified for specific target populations, to modify the students' behaviours so that they respect their own health and that of their fellow citizens.


Asunto(s)
Fumar/epidemiología , Estudiantes/estadística & datos numéricos , Encuestas y Cuestionarios , Adolescente , Adulto , Áreas de Influencia de Salud , Estudios Transversales , Femenino , Humanos , Italia/epidemiología , Masculino , Distribución por Sexo
8.
Aliment Pharmacol Ther ; 12(7): 635-9, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9701526

RESUMEN

BACKGROUND: The efficacy of omeprazole and amoxycillin dual therapy to treat Helicobacter pylori infection has been inconsistent, suggesting the presence of host or bacterial factors influencing treatment success. The aim of this study was to assess the role of pre-treatment amoxycillin resistance in the efficacy of omeprazole and amoxycillin dual therapy. METHODS: We studied 43 consecutive dyspeptic patients with H. pylori infection. Pre-treatment H. pylori infection was established by the combination of positive rapid urease test, culture and histology. Amoxycillin susceptibility testing was performed by an Epsilometer test (E-test) method and amoxycillin resistance was defined as minimum inhibitory concentration greater than 8 microg/mL. Patients received 20 mg omeprazole twice daily for 28 days and amoxycillin 1000 mg twice daily for 2 weeks. Adverse effects were documented using a questionnaire. H. pylori status was reassessed 6-8 weeks after the end of treatment by rapid urease testing and histological examination of gastric biopsies. RESULTS: Forty-two dyspeptic patients completed the study, and one patient dropped out. H. pylori infection was cured in 2 3 of 42 patients (55%). The cure rate was higher in patients harbouring amoxycillin-sensitive organisms than in those with resistant strains: 66% (19/29) vs. 31% (4/13), respectively (P = 0.049). No significant differences in cure rates were evident in relation to age, sex, smoking habits or compliance. CONCLUSIONS: The effectiveness of amoxycillin-omeprazole dual therapy was greatly reduced in the presence of pre-treatment amoxycillin-resistant H. pylori. The success rate in patients with amoxycillin-sensitive H. pylori was only 66%, suggesting the presence of additional factors affecting the efficacy of this therapy.


Asunto(s)
Amoxicilina/uso terapéutico , Antiulcerosos/uso terapéutico , Infecciones por Helicobacter/tratamiento farmacológico , Helicobacter pylori/efectos de los fármacos , Omeprazol/uso terapéutico , Resistencia a las Penicilinas , Penicilinas/uso terapéutico , Adulto , Anciano , Amoxicilina/efectos adversos , Antiulcerosos/efectos adversos , Quimioterapia Combinada , Femenino , Infecciones por Helicobacter/patología , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Omeprazol/efectos adversos , Cooperación del Paciente , Penicilinas/efectos adversos , Estudios Prospectivos , Encuestas y Cuestionarios
9.
J Chemother ; 6 Suppl 3: 19-22, 1994 Aug.
Artículo en Italiano | MEDLINE | ID: mdl-7861204

RESUMEN

Through the introduction of a 7-mercapto-1,3-thiazole chain at position 3' of the dihydrothiazine ring, cefodizime, which is structurally similar to cefotaxime, has acquired a number of remarkable immunomodulatory properties while retaining a potent antimicrobial spectrum of activity. Cefodizime penetrates in fact readily through the bacterial cell wall and interacts with its molecular targets in such a way that at high concentrations cell death and lysis are rapidly induced. Its spectrum of action encompasses the Enterobacteria, Neisseriae, Haemophilus, Moraxella catarrhalis, methicillin-susceptible staphylococci and streptococci, with pneumococci included. Cefodizime is devoid of useful potency against Pseudomonas, Acinetobacter and enterococci. Given the wide occurrence of strains synthesizing beta-lactamases in several primary pathogens of community-acquired and nosocomial infections, the complete stability of cefodizime towards the most prevalent of these hydrolytic enzymes (TEM-1, TEM-2, SHV-1, BRO-1 and the staphylococcal penicillinases) seems reassuring. Only a few chromosomally-coded and extended spectrum beta-lactamases produced by gram-negative microorganisms inactivate the new cephalosporin. Since the distribution of pathogens carrying these enzymes depends on the local trends of antibacterial consumption and cannot be easily predicted, a large multicenter study in Italy has recently assessed the antibacterial potency of cefodizime, in comparison with suitable drugs, on 1985 selected nosocomial strains. In this survey cefodizime was more effective in vitro than amoxicillin-clavulanate, gentamicin and piperacillin while being substantially similar in the rates of eradication of gram-negative and gram-positive organisms to other third generation cephalosporins like ceftazidime and ceftriaxone.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Adyuvantes Inmunológicos , Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Antibacterianos/uso terapéutico , Bacterias/aislamiento & purificación , Infecciones Bacterianas/tratamiento farmacológico , Infecciones Bacterianas/microbiología , Cefotaxima/análogos & derivados , Cefotaxima/farmacología , Cefotaxima/uso terapéutico , Cefalosporinas/farmacología , Cefalosporinas/uso terapéutico , Farmacorresistencia Microbiana , Humanos , Estudios Multicéntricos como Asunto
10.
J Chemother ; 2(5): 295-9, 1990 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1965317

RESUMEN

The authors evaluated the in-vitro antibacterial activity of piperacillin alone and of piperacillin combined with tazobactam, a new beta-lactamase inhibitor, on 398 clinical isolates, both Gram-positive and Gram-negative. The piperacillin/tazobactam combination was evaluated in the fixed ratio 8:1. The vast majority of the microorganisms tested had reduced susceptibility to piperacillin (minimum inhibitory concentration (MIC) range 0.12- greater than 256 mg/l) due to beta-lactamase production. The following results were obtained: against Haemophilus influenzae, tazobactam was effective in reducing the MICs of piperacillin by 512 fold. The activity of piperacillin/tazobactam was lower against Pseudomonas sp., while some activity was demonstrated against some strains of Klebsiella. Good activity was seen not only against methicillin-susceptible (MS) staphylococci but also against some methicillin-resistant (MR) strains. In the latter, the combination of piperacillin/tazobactam was active only if the strains showed beta-lactamase production. These findings are interesting above all in regard to the synergistic effect demonstrated against MR beta-lactamase producing staphylococci and the Klebsiella-Enterobacter-Serratia (KES) group.


Asunto(s)
Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Ácido Penicilánico/farmacología , Piperacilina/farmacología , beta-Lactamasas/biosíntesis , Sinergismo Farmacológico , Quimioterapia Combinada/farmacología , Bacterias Gramnegativas/enzimología , Bacterias Grampositivas/enzimología , Pruebas de Sensibilidad Microbiana , Tazobactam , Inhibidores de beta-Lactamasas
11.
Parassitologia ; 46(4): 371-3, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16044693

RESUMEN

Cystic echinococcosis is endemic in certain parts of the world, including Sardinia, Italy. It was performed a study in the province of Sassari in order to evaluate the incidence of the infection in man and the effects of control programs since 1964 to 2002. Data obtained by surgical records, hospital discharge forms, radiological and pathological files were collected using a case report form. During the years 1964-2002, 2702 new cases were identified (average annual incidence: 17 per 100,000) and 1981 (73.3%) were submitted to surgical treatment. In 57.3% municipalities no cases were observed during the years 1998-2002. Males are more affected (56.2%), mostly farmers-shepherdess (68.6 per 100,000) and pensioners (59.6 per 100,000). Control measures led to a significant decline in the incidence rate of hydatidosis during the period 1964-2002, dropping by 27.6 per 100,000. The mean age of surgical patients increased during the years of surveillance, such as the surgical liver/lung ratio as a consequence of a cohort effect. The durability of control programs is the corner stone for obtaining a significant decrease of this infection.


Asunto(s)
Equinococosis/epidemiología , Enfermedades Endémicas , Adulto , Anciano , Equinococosis/prevención & control , Equinococosis/cirugía , Femenino , Humanos , Incidencia , Italia/epidemiología , Masculino , Persona de Mediana Edad , Ocupaciones , Recurrencia
12.
New Microbiol ; 26(4): 375-81, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-14596348

RESUMEN

Anti-Mycobacterium tuberculosis drug-resistance, mainly multi-drug resistance (MDR-TB), represents an important public health problem in several countries. Aim of our study is to identify the presence of these mutations in M. tuberculosis isoniazid- and rifampin-resistant strains isolated in our Institute; to evaluate linkage between type of mutation and level of resistance; to determine the usefulness of easy molecular techniques for rapid detection of such mutations on body specimens. Isoniazid- and rifampin-resistance was tested on 67 M. tuberculosis strains by Single-Strand Conformation Polymorphism (SSCP) and Polymerase Chain Reaction-Restriction Fragment Length Polymorphism (PCR-RFLP) assays, using HaeIII, PstuI, BsteII, BstuI enzymes. Drug-resistance of control strains was determined by cultural techniques (fluorimetry- BACTEC 9120). Cultural assay showed isoniazid- and rifampin-resistance in 6.12 and 2%, respectively (data confirmed by SSCP assay). Mutation of katG, linked to isoniazid resistance, was detected using BstuI enzyme, and mutation of rpoB, expression of reduced sensitivity to rifampin, using HaeIII. 15 body specimens, M. tuberculosis-positive to conventional assays, were tested by SSCP technique. Epidemiologic reports of numerous cases of tuberculosis due to MDR strains induce to detect quickly both Mycobacteria and drug-resistance, in order to start prompt effective therapy. On this basis, molecular assays are useful for a rapid therapeutic decision.


Asunto(s)
Antituberculosos/farmacología , Isoniazida/farmacología , Mycobacterium tuberculosis/efectos de los fármacos , Mycobacterium tuberculosis/genética , Rifampin/farmacología , Farmacorresistencia Bacteriana , Humanos , Mutación Puntual , Polimorfismo de Longitud del Fragmento de Restricción , Polimorfismo Conformacional Retorcido-Simple , Sensibilidad y Especificidad
13.
Ann Ig ; 14(6 Suppl 7): 1-5, 2002.
Artículo en Italiano | MEDLINE | ID: mdl-12638358

RESUMEN

Since the introduction of the conjugate vaccine PnC-7, for the prevention of invasive pneumococcal infections for at-risk children, a controversy has arisen about the need for a universal vaccination under the age of two years. This article reviews the pathogenesis and the changing epidemiological pattern of pneumococcal diseases, the emergence of drug resistant S. pneumoniae and the costs and benefits of vaccination. Furthermore, the recommendations of various European countries and an up to date of the Italian ones are illustrated. It concludes with the public health perspective on the adoption of this pneumococcal vaccine and future recommendations for vaccination.


Asunto(s)
Meningitis Neumocócica/prevención & control , Vacunas Neumococicas/administración & dosificación , Vacunas Neumococicas/inmunología , Servicios Preventivos de Salud/organización & administración , Niño , Protección a la Infancia , Europa (Continente) , Humanos , Lactante , Italia , Vacunación Masiva , Vacunas Conjugadas/inmunología
19.
Diabetologia ; 49(1): 183-90, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16341686

RESUMEN

AIMS/HYPOTHESIS: Debate exists regarding the role of resistin in the pathophysiology of insulin resistance. The aim of this study was to directly assess the effects of resistin (0-24 h) on basal and insulin-stimulated glucose uptake and metabolism in skeletal muscle cells and to investigate the mechanisms responsible for the effects of resistin. METHODS: We used L6 rat skeletal muscle cells and examined [(3)H]2-deoxyglucose uptake, GLUT4 translocation and GLUT protein content. We assessed glucose metabolism by measuring the incorporation of D-[U-(14)C]glucose into glycogen, (14)CO(2) and lactate production, as well as the phosphorylation level and total protein content of insulin signalling proteins, including insulin receptor beta-subunit (IRbeta), insulin receptor substrate (IRS), Akt and glycogen synthase kinase-3beta (GSK-3beta). RESULTS: Treatment of L6 rat skeletal muscle cells with recombinant resistin (50 nmol/l, 0-24 h) reduced levels of basal and insulin-stimulated 2-deoxyglucose uptake and decreased insulin-stimulated GLUT4myc content at the cell surface, with no alteration in the production of GLUT4 or GLUT1. Resistin also decreased glycogen synthesis and GSK-3beta phosphorylation. Insulin-stimulated oxidation of glucose via the Krebs cycle was reduced by resistin, whereas lactate production was unaltered. Although insulin receptor protein level and phosphorylation were unaltered by resistin, production of IRS-1, but not IRS-2, was downregulated and a decreased tyrosine phosphorylation of IRS-1 was detected. Reduced phosphorylation of Akt on T308 and S473 was observed, while total Akt and Akt1, but not Akt2 or Akt3, production was decreased. CONCLUSIONS/INTERPRETATION: Our data show that resistin regulates the function of IRS-1 and Akt1 and decreases GLUT4 translocation and glucose uptake in response to insulin. Selective decreases in insulin-stimulated glucose metabolism via oxidation and conversion to glycogen were also induced by resistin. These observations highlight the potential role of resistin in the pathophysiology of type 2 diabetes in obesity.


Asunto(s)
Glucosa/metabolismo , Insulina/fisiología , Músculo Esquelético/fisiología , Resistina/farmacología , Animales , Línea Celular , Desoxiglucosa/metabolismo , Glucógeno/biosíntesis , Glucólisis/efectos de los fármacos , Homeostasis , Cinética , Músculo Esquelético/efectos de los fármacos , Mioblastos/efectos de los fármacos , Mioblastos/fisiología , Ratas , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiología
20.
Diabetologia ; 48(1): 132-9, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15619075

RESUMEN

AIMS/HYPOTHESIS: The aim of this study was to determine whether adiponectin elicits glucose uptake via increased GLUT4 translocation and to investigate the metabolic fate of glucose in skeletal muscle cells treated with globular adiponectin. MATERIALS AND METHODS: Basal and insulin-stimulated 2-deoxy-D: -[(3)H]glucose uptake, cell surface myc-tagged GLUT4 content, production of (14)CO(2) by oxidation of D: -[U-(14)C]glucose and [1-(14)C]oleate, and incorporation of D: -[U-(14)C]glucose into glycogen and lactate were measured in the presence and absence of globular adiponectin. RESULTS: RT-PCR and Western blot analysis revealed that L6 cells and rat skeletal muscle cells express AdipoR1 mRNA and protein. Globular adiponectin increased both GLUT4 translocation and glucose uptake by increasing the transport V(max) of glucose without altering the K(m). Interestingly, the incorporation of D: -[U-(14)C]glucose into glycogen under basal and insulin-stimulated conditions was significantly decreased by globular adiponectin, whereas lactate production was increased. Furthermore, globular adiponectin did not affect glucose oxidation, but enhanced phosphorylation of AMP kinase and acetyl-CoA carboxylase, and fatty acid oxidation. CONCLUSIONS/INTERPRETATION: The present study is the first to show that globular adiponectin increases glucose uptake in skeletal muscle cells via GLUT4 translocation and subsequently reduces the rate of glycogen synthesis and shifts glucose metabolism toward lactate production. These effects are consistent with the increased phosphorylation of AMP kinase and acetyl-CoA carboxylase and oxidation of fatty acids induced by globular adiponectin.


Asunto(s)
Glucógeno/biosíntesis , Péptidos y Proteínas de Señalización Intercelular/farmacología , Proteínas de Transporte de Monosacáridos/metabolismo , Proteínas Musculares/metabolismo , Músculo Esquelético/metabolismo , Adenilato Quinasa/metabolismo , Adiponectina , Animales , Línea Celular , Células Cultivadas , Glucosa/metabolismo , Transportador de Glucosa de Tipo 4 , Insulina/farmacología , Lactatos/metabolismo , Músculo Esquelético/efectos de los fármacos , Ácido Oléico/metabolismo , Transporte de Proteínas , Ratas , Receptores de Adiponectina , Receptores de Superficie Celular/genética , Receptores de Superficie Celular/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
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