Emerging evidence has suggested that leptin, an adipokine related to energy homeostasis, plays a role in cancer growth and metastasis. However, its impact on pancreatic cancer is rarely studied. In this study, we found that leptin's functional receptor Ob-Rb was expressed in pancreatic cancer cell lines. Treatment with leptin enhanced the migration and invasion of pancreatic cancer cells but di...

Mercer, Julian G., Kim M. Moar, Alexander W. Ross, Nigel Hoggard, and Peter J. Morgan. Photoperiod regulates arcuate nucleus POMC, AGRP, and leptin receptor mRNA in Siberian hamster hypothalamus. Am. J. Physiol. Regulatory Integrative Comp. Physiol. 278: R271–R281, 2000.—Siberian hamsters decreased body weight by 30% during 18 wk in short day (SD) vs. long day (LD) controls. Subsequent imposed ...

In obese Zucker diabetic fatty (ZDF) rats with mutant leptin receptors, pancreatic islets have an approximately 50-fold increase in fat (TG), overproduce nitric oxide (NO), and lack a normal proinsulin mRNA response to fatty acids. We overexpressed the wild-type full-length "b" isoform of the leptin receptor (OB-Rb) in ZDF islets by perfusing ZDF pancreata with recombinant adenovirus containing...

Leptin is a polypeptide hormone produced predominantly in adipocytes. It has been found to be implicated in the regulation of satiety and energy homeostasis. A role for leptin in reproduction was later suggested by findings that this hormone may be involved in the regulation of the hypothalamic-pituitary-gonadal axis via endocrine, paracrine and/or autocrine pathways. The objective of the study...

Because leptin has recently been shown to induce proliferation and/or differentiation of different cell types through different pathways, the aim of the present study was to investigate, in vitro, the influence of leptin on adipogenesis in rat preadipocytes. A prerequisite to this study was to identify leptin receptors (Ob-Ra and Ob-Rb) in preadipocytes from femoral subcutaneous fat. We observe...

Leptin, encoded for by the mouse ob gene, regulates feeding behavior and energy metabolism. Its receptor (Ob-R) is encoded by the mouse diabetic (db) gene and is mutated in the db/db mouse so that it lacks the cytoplasmic domain. We show that the full-length leptin receptor (Ob-Rb), which is believed to transmit the leptin signal, is expressed in pancreatic islets of ob/ob and wild-type mice, a...

Besides its role in body weight control leptin may also act as a vasoactive hormone. This study was designed to investigate whether leptin modifies angiotensin II (ANG II)-induced vascular responses. The expression of functional leptin receptors (OB-Rb) was detected in vascular smooth muscle cells (VSMCs) from adult Wistar rats by RT-PCR. Immunocytochemistry and Western blot analysis further sh...

It is in general agreement that proteins with high molecular weights do not cross the blood-brain barrier (BBB), because of the tight junctions between endothelial cells that characterize the cerebral microvasculature. The tight junctions are indeed essential features of the cerebrovascular system, which filtrates water-soluble molecules and protects parenchymal elements of the brain against po...