Home FOR AUTHORS Endocrine Regulations 2009 Endocrine Regulations Vol.43, No.3, p.99-106, 2009

Journal info

Quarterly, 50 pp. per issue 
Founded: 1967
ISSN 1210-0668
E-ISSN 1336-0329

Published in English

Aims and Scope
Editorial Info
Submission Guidelines

Select Journal







Webshop Cart

Your Cart is currently empty.

Info: Your browser does not accept cookies. To put products into your cart and purchase them you need to enable cookies.

Endocrine Regulations Vol.43, No.3, p.99-106, 2009

Title: ACTIVATION OF HYPOTHALAMIC NPY, AgRP, MC4R, AND IL-6 mRNA LEVELS IN YOUNG LEWIS RATS WITH EARLY-LIFE DIET-INDUCED OBESITY
Author: A. Stofkova, M. Skurlova, A. Kiss, B. Zelezna, S. Zorad, J. Jurcovicova

Abstract: Objective. Obesity represents a low-grade inflammatory disease and appears a risk factor for insulin resistance, but little is known on whether this may contribute to the development of autoimmune inflammatory diseases. The aim of this work was to study the early-life diet-induced obesity in Lewis rats which are known to be highly susceptible to autoimmunity.
Methods. Obesity was induced by reduced litter size (4 pups per litter) followed by high-fat diet (SHF rats). Control rats (8 pups per litter) were fed with standard diet (CN rats). Oral glucose tolerance test (3 g glucose per kg b.w.) was performed by intra-gastric tube in conscious rats after 12 h fast. Adipocyte size was assessed by light microscope after collagenase digestion. Hypothalamic arcuate (ARC) and paraventricular nuclei (PVN) were isolated by the punching technique. Target mRNAs were quantified by real-time PCR with the use of TaqMan probes and primers. Serum hormones (leptin, ghrelin, adiponectin, visfatin and insulin) were assayed by specific RIAs .
Results. During the experimental period SHF rats had the same body weight gain and caloric intake as CN rats. At the age of 8 weeks SHF rats showed increased epididymal fat mass and adipocyte volume, impaired glucose tolerance, normal basal fasting insulin, visfatin, and ghrelin level, but decreased adiponectin and high leptin level. In the ARC, the SHF rats showed increased expression of mRNA for orexigenic neuropeptide Y (NPY), agouti-related protein (AgRP) and anorexigenic pro-inflammatory cytokine IL-6. In the PVN, the SHF rats showed increased expression of mRNA for anorexigenic melanocortin 4 receptor (MC4R) and IL-6.
Conclusion. Overexpression of orexigenic NPY and AgRP in the ARC indicates leptin resistance in SHF rats. The increased expression of MC4R in PVN points to the activation of melanocortin anorexigenic system which, along with increased hypothalamic IL-6, might prevent the animals from overfeeding. Higher adiposity in these rats results from the high fat-diet composition and not from increased caloric intake. Furthermore, enhanced leptin production appears the main factor indicating the predisposition to autoimmunity in these overfed rats.

Keywords: Overnutrition – Glucose intolerance – Adiponectin – Leptin – Visfatin – Ghrelin – Hypothalamus – Orexigens
Year: 2009, Volume: 43, Issue: 3 Page From: 99, Page To: 106
doi:10.4149/endo_2009_03_99


download file



© AEPress s.r.o
Copyright notice: For any permission to reproduce, archive or otherwise use the documents in the ELiS, please contact AEP.