Searchable abstracts of presentations at key conferences in endocrinology

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...