The remarkable development and refinement of the Cre-loxP system coupled with the nonstop production of new mouse models and virus vectors have impelled the growth of various fields of investigation. In this article, I will discuss the data collected using these genetic tools in our area of interest, giving specific emphasis to the identification of the neuronal populations that relay leptin ac...

Leptin, the product of the ob gene, is involved in the control of ovarian functions. Leptin transcripts and OB proteins were localized in the porcine corpus luteum, but the regulatory mechanism of leptin mRNA expression and leptin secretion in porcine luteal cells remains unexplained. The aim of the present study was to: 1) determine level of leptin and long form of leptin receptor (OB-Rb) tran...

INTRODUCTION Clinical studies have shown either positive or in some other cases negative correlations between leptinemia and bone mineral density (BMD) or bone mineral content (BMC). OBJECTIVES The aim of the present study was to assess whether these discrepancies might be associated with the effect of G(-2548)A leptin or A326G and A668G leptin receptor gene polymorphisms on serum leptin conc...

This study was undertaken to investigate the changes in obesity (OB) gene expression and production of leptin in response to insulin in vitro and in vivo under euglycemic and hyperglycemic conditions in humans. Three protocols were used: 1) euglycemic clamp with insulin infusion rates at 40, 120, 300, and 1,200 mU / m / min carried out for up to 5 h performed in 16 normal lean individuals, 30 o...

Leptin and hypoxia are pro-fibrotic factors involved in fibrogenesis, however, the gene expression profiles remain to be fully elucidated. The aim of the present study was to investigate the regulatory roles of leptin and hypoxia on the L929 mouse fibroblast cell line. The cells were assigned to a normoxia, normoxia with leptin, hypoxia, and hypoxia with leptin group. The cDNA expression was de...

Correction of the obese state induced by genetic leptin deficiency reduces elevated levels of both blood glucose and hypothalamic neuropeptide Y (NPY) mRNA in ob/ob mice. To determine whether these responses are due to a specific action of leptin or to the reversal of the obese state, we investigated the specificity of the effect of systemic leptin administration to ob/ob mice (n = 8) on levels...

Leptin, the 16-kDa product of the obese (ob) gene, primarily secreted from adipose tissue, has been implicated to play an important role in the regulation of food intake and energy expenditure. This study investigated protective effect of leptin on trichostatin A-induced apoptotic on in vitro maturation ratio of buffalo oocytes. Ovaries were collected from abattoir and were transported...

Sympathetic stimulation has long been recognized to mobilise fatty acids from white adipose tissue. However, it is now apparent that adipose tissue is not only concerned with energy storage as fat, but is a major endocrine and secretory organ. This change has resulted from the identification of leptin as a hormone of energy balance secreted by white adipose tissue. The sympathetic system is a k...

Food restriction (FR) and refeeding (Re) have been suggested to impair body mass regulation and thereby making it easier to regain the lost weight and develop over-weight when FR ends. However, it is unclear if this is the case in small mammals showing seasonal forging behaviors. In the present study, energy budget, body fat and serum leptin level were measured in striped hamsters that were exp...

Leptin, an adipokine predominantly produced from adipose tissue, is well known to induce tumor growth. However, underlying molecular mechanisms are not established yet. While p53 has long been well recognized as a potent tumor suppressor gene, accumulating evidence has also indicated its potential role in growth and survival of cancer cells depending on experimental environments. In the present...