Loss of LEPR function (LOF) in mammals leads to diverse phenotypes including morbid obesity and infertility while zebrafish show relatively minor phenotypes. This however allows the study of LEPR LOF in the absence of the detrimental effects of hyperglycemia or obesity. Here, we show evidence that leptin plays a role in the central as well as peripheral regulation of the hypothalamic-pituitary-gonadal (HPG) axis in zebrafish. Animals with a Lepr LOF show dysregulated pituitary HPG genes as well as evidence that oocytes mature slower and/or exhibit an increased rate of atresia. In culture, Lepr LOF attenuates the effect of 17α-20β-dihydroxy-4 pregnen-3-one in promoting germinal vesicle breakdown (GVBD) and increases the rate of GVBD as well as attenuates the rate of oocyte atresia.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1530/JOE-22-0026 | DOI Listing |
Expert Rev Endocrinol Metab
March 2023
Rhythm Pharmaceuticals, Inc, Boston, MA, USA.
Objective: Hyperphagia and early-onset, severe obesity are clinical characteristics of rare melanocortin-4 receptor (MC4R) pathway diseases due to loss-of-function (LOF) variants in genes comprising the MC4R pathway. In vitro functional characterization of 12,879 possible exonic missense variants from single-nucleotide variants (SNVs) of , and was performed to determine the impact of these variants on protein function.
Methods: SNVs of the three genes were transiently transfected into cell lines, and each variant was subsequently classified according to functional impact.
J Endocrinol
May 2022
Institute of Zoology, University of Cologne, Cologne, Germany.
Loss of LEPR function (LOF) in mammals leads to diverse phenotypes including morbid obesity and infertility while zebrafish show relatively minor phenotypes. This however allows the study of LEPR LOF in the absence of the detrimental effects of hyperglycemia or obesity. Here, we show evidence that leptin plays a role in the central as well as peripheral regulation of the hypothalamic-pituitary-gonadal (HPG) axis in zebrafish.
View Article and Find Full Text PDFJ Endocrinol
August 2021
Institute of Zoology, University of Cologne, Cologne, Germany.
The leptin system plays a crucial role in the regulation of appetite and energy homeostasis in vertebrates. While the phenotype of morbid obesity due to leptin (Lep) or leptin receptor (LEPR) loss of function is well established in mammals, evidence in fish is controversial, questioning the role of leptin as the vertebrate adipostat. Here we report on three (Lepr) loss of function (LOF) and one leptin loss of function alleles in zebrafish.
View Article and Find Full Text PDFFront Cardiovasc Med
May 2021
Berlin Institute of Health at Charité - Universitätmedizin Berlin, BIH Center for Regenerative Therapies (BCRT), Berlin, Germany.
Mesenchymal stromal cells (MSCs) are an attractive cell type for cell therapy given their immunomodulatory, anti-fibrotic, and endothelial-protective features. The heparin sulfate proteoglycan, syndecan-2/CD362, has been identified as a functional marker for MSC isolation, allowing one to obtain a homogeneous cell product that meets regulatory requirements for clinical use. We previously assessed the impact of wild-type (WT), CD362, and CD362 MSCs on local changes in protein distribution in left ventricular (LV) tissue and on LV function in an experimental model of early-onset diabetic cardiomyopathy.
View Article and Find Full Text PDFJ Clin Endocrinol Metab
July 2018
Rhythm Pharmaceuticals, Boston, Massachusetts.
Context: The hypothalamic melanocortin 4 receptor (MC4R) pathway serves a critical role in regulating body weight. Loss of function (LoF) mutations in the MC4R pathway, including mutations in the pro-opiomelanocortin (POMC), prohormone convertase 1 (PCSK1), leptin receptor (LEPR), or MC4R genes, have been shown to cause early-onset severe obesity.
Methods: Through a comprehensive epidemiological analysis of known and predicted LoF variants in the POMC, PCSK1, and LEPR genes, we sought to estimate the number of US individuals with biallelic MC4R pathway LoF variants.
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!