Leptin or obesity receptor (Ob-R) is a member of class I cytokine receptor family. Ob-R, expressed in six isoforms, is the product of alternative RNA splicing of db gene. According to its structural differences, the receptor's isoforms are divided into three classes: long, short, and secretory isoforms. A long, fully active isoform of Ob-Rb is expressed mainly in the hypothalamus, where it take...

Leptin, the product of the Ob(Lep) gene, is a peptide hormone that plays a major role in maintaining the balance between food intake and energy expenditure. In the brain, leptin receptors are expressed by hypothalamic cells but also in the olfactory bulb, the first central structure coding for odors, suggesting a precise function of this hormone in odor-evoked activities. Although olfaction pla...

The risk of obesity (OB) in adulthood is strongly influenced by maternal body composition. Here we examined the hypothesis that maternal OB influences white adipose tissue (WAT) transcriptome and increases propensity for adipogenesis in the offspring, prior to the development of OB, using an established model of long-term metabolic programming. Employing an overfeeding-based rat model, in which...

Obesity and sleep fragmentation (SF) are often co-occurring pro-inflammatory conditions in patients with obstructive sleep apnea. Leptin is a peptide hormone produced by adipocytes that has anorexigenic effects upon appetite while regulating immunity. The role of leptin in mediating inflammatory responses to SF is incompletely understood. Male C57BL/6j (lean) and ob/ob mice (leptin-deficient mi...

Melanocortin-4 receptors (MC4Rs) are involved in the regulation of food intake, sympathetic nervous activity, and adrenal and thyroid function by leptin. The role of MC4Rs in regulating energy balance by leptin was investigated using double heterozygote or homozygous leptin (Lep(ob)) and Mc4r gene mutant mice. Double heterozygous or homozygous mutants were generated by crossing MC4R knockout (M...

Reduction in the activity of the a-melanocyte-stimulating hormone (a-MSH) system causes obesity, and infusions of a-MSH can produce satiety, raising the possibility that a-MSH may mediate physiological satiety signals. Since a-MSH is coded for by the pro-opiomelanocortin (POMC) gene, we examined if POMC gene expression would be inhibited by fasting in normal mice or in models of obesity charact...

Tumor necrosis factor (TNF) is a central mediator of a number of important pathologies such as the systemic inflammatory response syndrome. Administration of high TNF doses induces acute anorexia, metabolic derangement, inflammation, and eventually shock and death. The in vivo effects of TNF are largely mediated by a complex network of TNF-induced cytokines and hormones acting together or antag...

We previously demonstrated that polymorphisms in the carnosinase-1 gene (CNDP1) determine the risk of nephropathy in type 2 diabetic patients. Carnosine, the substrate of the enzyme encoded by this gene, is considered renoprotective and could possibly be used to treat diabetic nephropathy (DN). In this study, we examined the effect of carnosine treatment in vivo in BTBR (Black and Tan, BRachyur...

This study sought to determine the role of physical training (PT) on body weight (BW), energy balance, histological markers of nonalcoholic fatty liver disease (NAFLD) and metabolic gene expression in the liver of ob/ob mice. Adult male ob/ob mice were assigned into groups sedentary (S; n = 8) and trained (T; n = 9). PT consisted in running sessions of 60 min at 60% of maximal speed conducted f...

Apolipoprotein A-IV (apo A-IV) is a satiety factor involved in the control of food intake and body weight. Our previous studies demonstrated that apo A-IV is present in areas of the hypothalamus where leptin acts to influence energy homeostasis. In the present studies, we found that leptin-deficient obese (ob/ob) mice have significantly reduced hypothalamic apo A-IV mRNA levels. Intragastric in...