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...

Numerous studies have focused on the regulation of leptin signalling and the functions of leptin in energy homoeostasis; however, little is known about how leptin secretion is regulated. In the present study we studied leptin storage and secretion regulation in 3T3-L1 and primary adipocytes. Leptin is stored in membrane-bound vesicles that are localized predominantly in the ER (endoplasmic reti...

Leptin is a hormone that is secreted by adipose cells in proportion to adipose mass, and therefore a low leptin level signifies depletion of energy stores. It has been proposed that leptin is one of the signals controlling sexual maturation. For example, humans and rodents lacking leptin fail to undergo complete puberty, while overexpression of leptin in mice causes early puberty. The placenta ...

Leptin is an adipose tissue derived hormone, which has a crucial role in regulating food intake and energy expenditure. Leptin is also an important metabolic regulator, which maintains glucose and lipid homeostasis. After identification of its influences on body weight and fat mass in leptin deficient obese rodent models, leptin supplementation was used for the treatment of obesity in human. Ho...

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....

THE CONCEPT OF LEPTIN RESISTANCE appeared in the literature almost as soon as the hormone itself was discovered. For purposes of our discussion, leptin resistance will be defined as, “reduced or absent responsiveness to the feeding and body weight inhibitory effects of the hormone in obese individuals in comparison with normal (lean) controls.” Two early reports, demonstrating significant corre...

BACKGROUND AND AIM The circulating peptide leptin produced by fat cells acts on central receptors to control food intake and body weight homeostasis. Contrary to initial reports, leptin expression has also been detected in the human placenta, muscles, and recently, in rat gastric chief cells. Here we investigate the possible presence of leptin and leptin receptor in the human stomach. METHODS...

Leptin is a hormone which functions in the regulation of energy homeostasis via suppression appetite. In zebrafish, there are two paralogous genes encoding leptin, called lepa and lepb . gene expression study, we found that gene, not , was significantly downregulated under state insulin-resistance zebrafish larvae, suggesting plays role glucose homeostasis. current characterised -deficient ( −/...

Leptin is an adipocyte-secreted hormone that has effects on appetite and energy expenditure. Several studies have shown that end-stage renal disease results in elevated plasma leptin concentrations and that the kidney is responsible for most of leptin elimination in rodents. Leptin metabolism was investigated in rats that underwent unilateral nephrectomy to experimentally limit renal eliminatio...

Leptin exerts its action by binding to and activating the long form of leptin receptors (LEPRb). LEPRb activates JAK2 that subsequently phosphorylates and activates STAT3. The JAK2/STAT3 pathway is required for leptin control of energy balance and body weight. Defects in leptin signaling lead to leptin resistance, a primary risk factor for obesity. Body weight is also regulated by nutrients, in...