Artículos y presentaciones en Congresos



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  • VMP1- Related autophagy induced by fructose rich diet in β-cells: its prevention by incretins
    ( 2017) Maiztegui, Bárbara ; Boggio, Verónica ; Román, Carolina Lisi ; Flores, Luis Emilio ; Del Zotto, Héctor ; Ropolo, Alejandro ; Grasso, Daniel ; Vaccaro, María I. ; Gagliardino, Juan José
    To demonstrate the role of autophagy and incretins on fructose‐induced alteration in β‐cell mass and function. Methods: Normal Wistar rats were fed (3 weeks) with commercial diet without (C) or with 10% fructose in drinking water (F) alone or plus sitagliptin (CS and FS) or exendin‐4 (CE and FE). Serum levels of metabolic/endocrine parameters, β‐cell mass, morphology/ultrastructure and apoptosis, VMP1 expression and glucose‐stimulated insulin secretion (GSIS) were studied. Complementary, islets isolated from normal rats were cultured (3 days) without (C) or with F and F plus exendin‐4 (FE) or chloroquine (FCQ). Expression of autophagy related‐proteins (VMP1 and LC3), apoptotic/antiapoptotic markers (caspase‐3 and Bcl‐2), GSIS and insulin mRNA levels were measured. Results: F rats developed impaired glucose tolerance (IGT) and a significant increase in plasma triglyceride, TBARS, insulin levels, HOMAIR and HOMA‐β indexes. Significant β‐cell mass reduction was associated to an increased apoptotic rate and morphological/ultrastructural changes indicative of autophagic activity. All these changes were prevented by either sitagliptin or exendin‐4. In cultured islets, F significantly enhanced insulin mRNA and GSIS, decreased Bcl‐2 mRNA levels and increased caspase‐3 expression. Chloroquine reduced these changes suggesting autophagy participation in this process. Indeed, F induced the increase of both, VMP1 expression and LC3‐II, suggesting that VMP1‐related autophagy is activated in injured β‐cell. Exendin‐4 prevented islet‐cell damage and autophagy development. Conclusions: VMP1‐related autophagy is a reactive process against Finduced islet dysfunction, being prevented by exendin‐4 treatment. This knowledge could help to use autophagy as potential target for preventing progression from IGT toT2DM.
  • Estudio exploratorio de la oferta de bebidas sin alcohol en comercios mayoristas y minoristas de ciudad de La Plata
    ( 2017) Papalardo, Brenda ; García, Silvia ; Prestes, Mariana ; Fasano, María Victoria ; Olmedo, Luciana ; Henning, María Florencia ; Malpeli, Agustina ; Bisceglia, María Gabriela ; Pellon Maison, Magali
    Los hábitos de consumo alimentario actuales promueven el sobrepeso y la obesidad. Se consiguen alimentos a menores precios, particularmente aquellos con una alta densidad energética y con mayor grado de procesamiento, como las bebidas endulzadas con edulcorantes calóricos. La Argentina se posiciona como uno de los líderes del mercado y como uno de los mayores consumidores a nivel mundial de este tipo de bebidas. Los objetivos de este trabajo fueron: -Explorar el contenido total de hidratos de carbono y tipo de edulcorante de las bebidas sin alcohol ofrecidas a la venta en comercios de La Plata. -Comparar la oferta de bebidas sin alcohol y su contenido en edulcorantes calóricos y no calóricos en comercios de centros comunales de diferente nivel socioeconómico.
  • Effect of Pioglitazone on the Fructose-Induced Abdominal Adipose Tissue Dysfunction
    (Hindawi Publishing Corporation, 2012) Alzamendi, Ana ; Giovambattista, Andrés ; Garcia, María Elisa ; Rebolledo, Oscar R. ; Gagliardino, Juan José ; Spinedi, Eduardo
    Aim. To test the potential role of PPARγ in the endocrine abdominal tissue dysfunction induced by feeding normal rats with a fructose rich diet (FRD) during three weeks. Methodology. Adult normal male rats received a standard commercial diet (CD) or FRD, (10% in drinking water) without or with pioglitazone (PIO) (i.p. 0.25mg/Kg BW/day; CD-PIO and FRD-PIO). Thereafter, we measured circulating metabolic, endocrine, and oxidative stress (OS) markers, abdominal adipose tissue (AAT) mass, leptin (LEP) and plasminogen activator inhibitor-1 (PAI-1) tissue content/expression, and leptin release by isolated adipocytes incubated with different concentrations of insulin. Results. Plasma glucose, insulin, triglyceride, TBARS, LEP, and PAI-1 levels were higher in FRD rats; PIO coadministration fully prevented all these increments. AAT adipocytes from FRD rats were larger, secreted a higher amount of LEP, and displayed decreased sensitivity to insulin stimulation; these effects were significantly ameliorated by PIO. Whereas AAT LEP and PAI-1 (mRNA) concentrations increased significantly in FRD rats, those of insulin-receptor-substrate- (IRS-) 1 and IRS-2 were reduced. PIO coadministration prevented FRD effects on LEP, PAI-1, and IRS-2 (fully) and IRS-1 (partially) mRNAs in AAT. Conclusion. PPARγ would play a relevant role in the development of the FRD-induced metabolicendocrine dysfunction.
  • Oral Metformin Treatment Prevents Enhanced Insulin Demand and Placental Dysfunction in the Pregnant Rat Fed a Fructose-Rich Diet
    (Hindawi Publishing Corporation, 2012) Alzamendi, Ana ; Del Zotto, Héctor ; Castrogiovanni, Daniel ; Romero, José ; Giovambattista, Andrés ; Spinedi, Eduardo
    The intake of a fructose-rich diet (FRD) in the normal female rat induces features similar to those observed in the human metabolic syndrome phenotype. We studied the impact of FRD administration to mothers on pregnancy outcome. On gestational day (Gd) zero rats were assigned to either group: ad libitum drinking tap water alone (normal diet, ND) or containing fructose (10% w/vol; FRD) through pregnancy; all rats were fed a Purina chow diet ad libitum ND and FRD rats were daily cotreated or not with metformin (60 mg/Kg/day oral; ND + MF and FRD + MF) and submitted to a high glucose load test on Gd 14. Additionally, placentas from different groups were studied on Gd 20. Data indicated that: (1) although FRD rats well tolerated glucose overload, their circulating levels of insulin were significantly higher than in ND rats; (2) the mesometrial triangle blood vessel area was significantly lower in placentas from FRD than ND dams; (3) the detrimental effects of FRD administration to mothers were ameliorated by metformin cotreatment. Our study suggests that excessive intake of fructose during pregnancy enhanced the risk for developing gestational diabetes and subsequent preeclampsia, and that metformin prevented the poor pregnancy outcome induced by FRD.
  • Relationship between the Balance of Hypertrophic/Hyperplastic Adipose Tissue Expansion and the Metabolic Profile in a High Glucocorticoids Model
    ( 2016) Zubiría, Guillermina ; Alzamendi, Ana ; Moreno, Griselda ; Portales, Andrea Estefanía ; Castrogiovanni, Daniel ; Spinedi, Eduardo ; Giovambattista, Andrés
    Adipose tissue (AT) expansion is the result of two processes: hyperplasia and hypertrophy; and both, directly or indirectly, depend on the adipogenic potential of adipocyte precursor cells (APCs). Glucocorticoids (GCs) have a potent stimulatory effect on terminal adipogenesis; while their effects on early stages of adipogenesis are largely unknown. In the present work, we study, in a model of high GC levels, the adipogenic potential of APCs from retroperitoneal AT (RPAT) and its relationship with RPAT mass expansion. We employed a model of hyper-adiposity (30- and 60-day-old rats) due to high endogenous GC levels induced by neonatal treatment with L-monosodium glutamate (MSG).We found that the RPAT APCs from 30-day-old MSG rats showed an increased adipogenic capacity, depending on the APCs’ competency, but not in their number. Analyses of RPAT adipocyte diameter revealed an increase in cell size, regardless of the rat age, indicating the prevalence of a hypertrophic process. Moreover, functional RPAT alterations worsened in 60-day-old rats, suggesting that the hyperplastic AT expansion found in 30-day-old animals might have a protective role. We conclude that GCs chronic excess affects APCs’ adipogenic capacity, modifying their competency. This change would modulate the hyperplastic/hypertrophic balance determining healthy or unhealthy RPAT expansion and, therefore, its functionality.