Searchable abstracts of presentations at key conferences in endocrinology

ea0029p1112 | Neuroendocrinology | ICEECE2012

Crf type 2 receptor mediates estradiol-induced increase in hypothalamic leptin sensitivity

Marangon P. , Antunes-Rodrigues J. , Elias L.

Energy homeostasis is controlled by neural, endocrine and adipocyte factors and CNS plays a key role in this control. We have previously observed that ovariectomized (OVX) rats treated with estradiol have lower body weight gain associated with an increased hypothalamic CRF mRNA expression. We investigated the role of CRF on activation of hypothalamic CART neurons by leptin in estradiol-treated OVX rats. Female Wistar rats (200–250 g) were subjected to both OVX and cannula...

ea0029p834 | Endocrine tumours and neoplasia | ICEECE2012

Expression of MAPK7 and CCNL1 in corticotrophinomas and functional analysis of miR-143 and miR-145 in corticotrophic tumoral lineage AtT20

Camargo R. , Paixao B. , Colli L. , Varanda W. , Rodrigues J. , Elias L. , Castro M.

Introduction: miR143 and 145 seem to be involved in the pathogenesis of cortitotrophinomas by modulating the expression of MAPK7 and CCNL1 genes, which protein products are involved in cell proliferation, differentiation, and cell cycle progression. Objective: To analyze the modulation of miR-143 and -145 in the expression of MAPK7 and CCNL1 genes in corticotrophinomas and corticotrophic tumoral lineage (AtT20).Material and Methods: The expression of MAP...

ea0029p1131 | Neuroendocrinology | ICEECE2012

Estradiol effects on hypothalamic stat3 phosphorylation induced by leptin

Goncalves G. , Borges B. , Marangon P. , Melo C. , Elias L. , Antunes-Rodrigues J.

Besides its critical functions as a reproductive hormone, 17β-estradiol (E2), plays an important role in the control of energy homeostasis. In experimental animals, reduction of circulating estrogen levels by bilateral ovariectomy leads to the development of obesity, which can be reversed or prevented by E2 treatment. E2 effects on energy balance resemble many similarities to the actions of leptin, key molecule involved in the control of e...

ea0029p1136 | Neuroendocrinology | ICEECE2012

Leptin resistance and desensitization of hypophagia during prolonged inflammatory challenge are associated with high ptp1b expression in the hypothalamus

Borges B. , Rorato R. , Marangon P. , Uchoa E. , Antunes-Rodrigues J. , Elias L.

Repeated exposure to lipopolysaccharide (LPS) leads to endotoxin tolerance. Desensitization of hypophagia in response to repeated exposure to endotoxin is related to an inability of leptin to phosphorylate STAT-3 protein. Protein tyrosine phosphatase 1B (PTP1B) activity is known to contribute to leptin resistance by inhibiting leptin signaling. In this study, we induced endotoxin tolerance, injecting repeated LPS doses (6LPS) (100 μg/kg, i.p.) in comparison with single (1...