Search results for "Leptin receptor"

Notch-1 decreased expression contributes to leptin receptor downregulation in nasal epithelium from allergic turbinates

2019

Abstract BACKGROUND: Allergic rhinitis is characterized by a remodeling of nasal epithelium. Since the Notch and TGF-β signaling pathways are known to be involved in cell differentiation and remodeling processes and leptin adipokine has already been identified as a marker for homeostasis in human bronchial and nasal epithelial cells of asthmatics, roles played by these pathways have been investigated for chronic allergic rhinitis. METHODS: The leptin/leptin receptor expression has been investigated in a study with 40 biopsies from allergic (AR, n = 18) and non-allergic (C, n = 22) inferior turbinates, using immunohistochemistry, immunofluorescence staining and RT-PCR. In addition, extracts …

Resistin, visfatin, leptin and omentin are differently related to hormonal and metabolic parameters in growth hormone-deficient children

2016

PURPOSE: The effect of growth hormone (GH) on adipose tissue and the role of adipokines in modulating metabolism are documented, but with discordant data. Our aim was to evaluate the impact of GH treatment on a series of selected adipokines known to have a metabolic role and poorly investigated in this setting. METHODS: This is a prospective study. Thirty-one prepubertal children (25 M, 6 F; aged 8.5 ± 1.6 years) with isolated GH deficiency treated with GH for at least 12 months and 30 matched controls were evaluated. Auxological and metabolic parameters, insulin sensitivity indexes, leptin, soluble leptin receptor, adiponectin, visfatin, resistin, omentin, adipocyte fatty acid-binding prot…

Genome-wide association study of non-alcoholic fatty liver and steatohepatitis in a histologically characterised cohort☆

2020

Background & Aims: Genetic factors associated with nonalcoholic fatty liver disease (NAFLD) remain incompletely understood. To date, most genome-wide association studies (GWASs) have adopted radiologically assessed hepatic triglyceride content as the reference phenotype and so cannot address steatohepatitis or fibrosis. We describe a GWAS encompassing the full spectrum of histologically characterised NAFLD. Methods: The GWAS involved 1,483 European NAFLD cases and 17,781 genetically matched controls. A replication cohort of 559 NAFLD cases and 945 controls was genotyped to confirm signals showing genome-wide or close to genome-wide significance. Results: Case-control analysis identified…

Differential Impact of Ad Libitum or Intermittent High-Fat Diets on Bingeing Ethanol-Mediated Behaviors

2019

Background: Dietary factors have significant effects on the brain, modulating mood, anxiety, motivation and cognition. To date, no attention has been paid to the consequences that the combination of ethanol (EtOH) and a high-fat diet (HFD) have on learning and mood disorders during adolescence. The aim of the present work was to evaluate the biochemical and behavioral consequences of ethanol binge drinking and an HFD consumption in adolescent mice. Methods: Animals received either a standard diet or an HFD (ad libitum vs. binge pattern) in combination with ethanol binge drinking and were evaluated in anxiety and memory. The metabolic profile and gene expression of leptin receptors and clock…

2021

The mechanisms underlying the transport of leptin into the brain are still largely unclear. While the leptin receptor has been implicated in the transport process, recent evidence has suggested an additional role of LRP2 (megalin). To evaluate the function of LRP2 for leptin transport across the blood-brain barrier (BBB), we developed a novel leptin-luciferase fusion protein (pLG), which stimulated leptin signaling and was transported in an in vitro BBB model based on porcine endothelial cells. The LRP inhibitor RAP did not affect leptin transport, arguing against a role of LRP2. In line with this, the selective deletion of LRP2 in brain endothelial cells and epithelial cells of the choroid…

Insulin sensitivity and secretion and adipokine profile in patients with Cushing’s disease treated with pasireotide

2018

Purpose: To evaluate the effect of pasireotide on β-cell and adipose function in patients with Cushing’s disease (CD). Methods: Clinical and hormonal parameters, insulin secretion evaluated by HOMA-β and by the area under the curve (AUC2h) of C-peptide during a mixed meal tolerance test and insulin sensitivity, evaluated by the euglycaemic hyperinsulinaemic clamp, were evaluated in 12 patients with active CD, before and after 6 and 12 months of pasireotide. In addition, a panel of adipokines including leptin (Ob), leptin/leptin receptor ratio (Ob/Ob-R ratio), adiponectin, resistin, visfatin, adipocyte fatty acid binding protein (AFABP) and non-esterified fatty acids (NEFAs) was evaluated at…

Effects of leptin on lipopolysaccharide-induced myometrial apoptosis in an in vitro human model of chorioamnionitis.

2011

Objective This study was aimed at assessing the role of leptin on human myometrium, by studying its receptor expression in pregnant myometrium and the interaction of leptin with inflammation-induced apoptosis. Study Design Myometrial samples were obtained from women with uncomplicated pregnancies who underwent cesarean delivery at term before labor onset. The effect of leptin on apoptosis was assessed by the incubation of myometrial strips with leptin (10 –10 to 10 –8 mol/L; 48 hours) before lipopolysaccharide treatment (10 μg/mL; 48 hours). Results Long and short leptin receptor isoforms were expressed in myometrial cells of pregnant women. Leptin prevented lipopolysaccharide-induced apopt…

Expression of the obesity hormone leptin and its receptor correlates with hypoxia-inducible factor-1 alpha in human colorectal cancer.

2007

Background: The obesity hormone, leptin, has been found to play a role in development and proliferation of normal and malignant tissues. Leptin activity is mediated through the leptin receptor (ObR) that is often expressed in different human cancer cells. Previously, we found that the expression of leptin and ObR can be stimulated by hypoxia-mimetic agents. The aim of this study was to analyze the abundance of and relationships among leptin, ObR and hypoxia-inducible factor-1α (HIF-1α, transcriptional regulator) in human colorectal cancer. Materials and methods: We investigated the expression of leptin, ObR and HIF-1 a in colorectal cancer specimens from 135 patients who underwent curative …

Serum visfatin levels in acromegaly: Correlation with disease activity and metabolic alterations

2015

Objective: The studies that have extensively evaluated the relation between adipokines and metabolic parameters in acromegaly treatment are quite discordant. We aimed to evaluate and correlate a set of selected adipokines, known to have a metabolic role, with the disease activity, metabolic status and treatment modalities. Design: Data of 56 consecutive acromegalic patients (31 M and 25 F; aged 54 ± 12 years), admitted to the section of Endocrinology of the University of Palermo during the years 2005-2014, including 16 newly diagnosed untreated (ND), 21 during therapy with somatostatin analogues (SA), 12 with pegvisomant (PE) and 7 after surgical treatment (SU), grouped into uncontrolled (g…

Leptin and leptin receptor expression in asthma.

2009

Background The adipokine leptin is a potential new mediator for bronchial epithelial homeostasis. Asthma is a chronic inflammatory disease characterized by airway remodeling that might affect disease chronicity and severity. TGF-β is a tissue growth factor the dysregulation of which is associated with airway remodeling. Objective We sought to determine whether a bronchial epithelial dysfunction of the leptin/leptin receptor pathway contributes to asthma pathogenesis and severity. Methods We investigated in vitro the presence of leptin/leptin receptor on human bronchial epithelial cells. Then we studied the effect of TGF-β and fluticasone propionate on leptin receptor expression. Finally, th…