The transition to puberty and adult fertility both require a minimum level of energy availability. The adipocyte-derived hormone leptin signals the long-term status of peripheral energy stores and serves as a key metabolic messenger to the neuroendocrine reproductive axis. Humans and mice lacking leptin or its receptor fail to complete puberty and are infertile. Restoration of leptin levels in ...

BACKGROUND Several studies suggest that changes in estrogens and androgens during menopause play a role in the regulation of leptin production. Some authors present hypothesis that sex hormone replacement therapy can modulate leptin levels but up to date evidence shows that the influence of endogenous estrogens, androgens levels and sex hormone therapy on leptin concentration remains uncertain....

Objective(s) Plasma leptin exists in protein-bound and free forms, which may affect its hormonal bioactivity. The free and bound forms are changed by the body weight. The purpose of this study was to evaluate the effect of metformin on bound and free plasma leptin concentration. Materials and Methods Subjects recruited from Yazd Diabetes Research Centre, Yazd University of Medical Sciences. ...

Leptin is a hormone secreted primarily by adipose tissue and its blood levels depend on the amount of fat stored in adipocytes. Leptin has a wide range of physiological effects. Acting directly or through the sympathetic nervous system it participates in the regulation of energy metabolism. Leptin inhibits synthesis of triacylglycerols in the liver, adipose tissue and skeletal muscles, thus red...

Unravelling the diverse hormonal and neuroendocrine systems which regulate energy balance and body fat has been a long-standing challenge in biology, with obesity as an increasingly important public health focus. A major development in energy balance regulation has come with the discovery in 1994 of a 'new' hormone, leptin, the protein product of the ob (obese) gene (Zhang et al. 1994). The ini...

objective(s) plasma leptin exists in protein-bound and free forms, which may affect its hormonal bioactivity. the free and bound forms are changed by the body weight. the purpose of this study was to evaluate the effect of metformin on bound and free plasma leptin concentration. materials and methods subjects recruited from yazd diabetes research centre, yazd university of medical sciences. the...

Leptin is an adipocyte-derived hormone that plays an important role in the regulation of energy homeostasis through its action in the central nervous system. Leptin decreases body weight by promoting satiety and increasing thermogenesis via increasing sympathetic nerve activity (SNA) to brown adipose tissue. Leptin also increases renal SNA and arterial pressure. The arcuate nucleus is considere...

Leptin-deficient obese mice (ob/ob) have decreased circulating growth hormone (GH) and pituitary GH and ghrelin receptor (GHS-R) mRNA levels, whereas hypothalamic GH-releasing hormone (GHRH) and somatostatin (SST) expression do not differ from lean controls. Given the fact that GH is suppressed in diet-induced obesity (a state of hyperleptinemia), it remains to be determined whether the absence...