Leptin is a polypeptide that plays a key role in the regulation of energy homeostasis and is also linked, among others, to mechanisms controlling reproductive processes. Data concerning the involvement of leptin in controlling reproductive functions at the level of hypothalamus and pituitary in the pig are limited. Therefore, in the present study, an expression of genes coding for leptin and lo...

Leptin receptors are constitutively endocytosed in a ligand-independent manner. To study their endocytosis, leptin receptors OB-Ra and OB-Rb were expressed in HeLa cells. Both receptor isoforms were ubiquitylated, internalized by clathrin-mediated endocytosis and transported to Hrs-positive endosomes after their internalization. Proteasome inhibitors inhibited OB-Ra but not OB-Rb internalizatio...

INTRODUCTION Leptin is a peptide hormone with a role in bone metabolism and rheumatic diseases. The subchondral bone tissue plays a prominent role in the pathophysiology of osteoarthritis (OA), related to abnormal osteoblast (Ob) differentiation. Although leptin promotes the differentiation of Ob under normal conditions, a role for leptin in OA Ob has not been demonstrated. Here we determined i...

Adiponectin is protective against hepatic fibrosis, whereas leptin promotes fibrosis. In HSCs (hepatic stellate cells), leptin signals via a JAK2 (Janus kinase 2)/STAT3 (signal transducer and activator of transcription 3) pathway, producing effects that enhance ECM (extracellular matrix) deposition. SOCS-3 (suppressor of cytokine signalling-3) and PTP1B (protein tyrosine phosphatase 1B) are bot...

Body weight and fat mass vary distinctly between German Holstein (dairy cattle) and Charolais (beef cattle). The aim of this study was to determine whether the expression of the obese (Ob) gene and lipoprotein lipase (LPL) gene in fat tissues and expression of the long isoform leptin receptor (Ob-Rb) gene in the hypothalamus were different between these two cattle breeds. Body weight and the ar...

Ob-Rb: Long isoform of leptin receptor. Ob-Ra, Ob-RcÖOb-Rf: Short isoforms of leptin receptor. FSH: Follicle stimulating hormone. IGF-I: Insulin-like growth factor type 1. BCL-2: B-cell lymphoma 2. Bax: Bcl-2-associated X protein. DMEM: Dulbecco’s Modified Eagle Medium. ER: Estrogen receptor alpha. ER: Estrogen receptor beta. AR: Androgen receptor. LHR: Luteinizing hormone receptor. FSHR: Folli...

Plasma leptin levels are elevated in obesity suggesting a pathophysiologic role of this hormone in obesity and related disorders, such as hypertension. Furthermore, despite excess leptin levels, leptin satiety action is blunted in obesity suggesting the occurrence of central leptin resistance. As leptin acts on the kidney to induce natriuresis, renal leptin receptor alterations could lead to a ...

OBJECTIVE To characterize the psychometric properties of a novel Obstetric Communication Assessment Tool (OCAT) in a pilot study of standardized difficult OB communication scenarios appropriate for undergraduate medical evaluation. METHODS We developed and piloted four challenging OB Standardized Patient (SP) scenarios in a sample of twenty-one third year OB/GYN clerkship students: Religious ...

Leptin, the adipocyte-produced hormone that plays a key role in body weight homeostasis, has recently been found to be involved in the regulation of the hypothalamic-pituitary-adrenal axis. Moreover, reciprocal interactions between leptin and glucocorticoids have been described. In the present communication, two different strategies were undertaken to explore the mode of action of leptin in the...

Three experiments were performed to investigate the hypothesis that leptin action within the caudal brain stem (CBS) contributes to its intake inhibitory effects. The first experiment evaluated the anatomical distribution of leptin receptor mRNA in rat CBS using a sensitive fluorescence in situ hybridization method with a riboprobe specific for the long form of the leptin receptor (Ob-Rb). An O...