Food restriction and weight loss result in reduced plasma leptin, which is associated with a pleiotropic biologic response. However, because weight loss itself is also associated with changes in numerous other humoral and metabolic signals, it can be difficult to determine the precise features of the biologic response to acute leptin deficiency. To study this response in the absence of changes ...

The identification of spontaneous mutations in the leptin- and leptin receptor (ObR)-encoding ob and db gene, respectively, opened up a new field in obesity research. Leptin, an adipocyte-derived hormone, mirrors the body's fat stores and thereby informs the brain about the body's energy status. In the hypothalamus, leptin triggers specific neuronal subpopulations, like POMC and AgRP/NPY neuron...

Leptin is vital for maintaining energy homeostasis, by controlling food intake and regulating expenditure (fatty acids). It also participates in glycemic thyroid activity, reproductive immune functions. resistance a phenomenon that appears gradually does not simultaneously affect all organs tissues equally. In models of obesity induced high-fat diet, leptin initially manifests the hypothalamus....

OBJECTIVE Leptin resistance is a common hallmark of obesity. Rats on a free-choice high-fat high-sugar (fcHFHS) diet are resistant to peripherally administered leptin. The aim of this study was to investigate feeding responses to central leptin as well as the associated changes in mRNA levels in hypothalamic and mesolimbic brain areas. DESIGN AND METHODS Rats on a CHOW or fcHFHS diet for 8 da...

The positive correlation between leptin and body fat mass has caused some investigators to speculate that leptin resistance contributes to obesity. Loss of ovarian function in human and rat is associated with increased fat mass gain and increased circulating leptin levels. To study whether ovariectomy produces leptin resistance, Sprague-Dawley female rats were ovariectomized or sham operated an...

background obesity is a medical problem in survivors of childhood acute lymphoblastic leukemia. obesity is associated with many complications, so it is important to investigate the respective etiology. leptin is a protein synthesized in the fatty tissue and is effective in the control of obesity. survey of leptin in acute lymphoblastic leukemia (all) survivors could be helpful in controlling ob...

The consumption of diets rich in saturated fat largely contributes to the development of obesity in modern societies. A diet high in saturated fats can induce inflammation and impair leptin signaling in the hypothalamus. However, the role of saturated fatty acids on hypothalamic leptin signaling, and hepatic glucose and lipid metabolism remains largely undiscovered. In this study, we investigat...

Ingestion of high-fat, high-calorie diets is associated with hyperphagia, increased body fat, and obesity. The mechanisms responsible are currently unclear; however, altered leptin signaling may be an important factor. Vagal afferent neurons (VAN) integrate signals from the gut in response to ingestion of nutrients and express leptin receptors. Therefore, we tested the hypothesis that leptin re...

Madiehe, Abram M., Tiffany D. Mitchell, and Ruth B. S. Harris. Hyperleptinemia and reduced TNFsecretion cause resistance of db/db mice to endotoxin. Am J Physiol Regul Integr Comp Physiol 284: R763–R770, 2003; 10.1152/ ajpregu.00610.2002.—Leptin deficiency in ob/ob mice increases susceptibility to endotoxic shock, whereas leptin pretreatment protects them against LPS-induced lethality. Lack of ...

In 1969, Douglas Coleman joined the bodies of an obese and a normal mouse by a procedure called parabiosis. Days later, the normal mouse starved. Something had taken away its desire to eat [1]. It was not until almost 25 years later that the true nature of what Coleman then called "satiety factor" was revealed. In 1994, Jeffrey Friedman identified the adipocytic hormone leptin [2,3] and it was ...