Photoperiodic changes in adiposity increase sensitivity of female Siberian hamsters to systemic VGF derived peptide TLQP-21

Lisci, C. et al. (2019) Photoperiodic changes in adiposity increase sensitivity of female Siberian hamsters to systemic VGF derived peptide TLQP-21. PLoS ONE, 14(8), e0221517. (doi: 10.1371/journal.pone.0221517) (PMID:31465472) (PMCID:PMC6715173)

Abstract

TLQP-21, a peptide encoded by the highly conserved vgf gene, is expressed in neuroendocrine cells and has been the most prominent VGF-derived peptide studied in relation to control of energy balance. The recent discovery that TLQP-21 is the natural agonist for the complement 3a receptor 1 (C3aR1) has revived interest in this peptide as a potential drug target for obesity. We have investigated its function in Siberian hamsters (Phodopus sungorus), a rodent that displays natural seasonal changes in body weight and adiposity as an adaptation to survive winter. We have previously shown that intracerebroventricular administration of TLQP-21 reduced food intake and body weight in hamsters in their long-day fat state. The aim of our current study was to determine the systemic actions of TLQP-21 on food intake, energy expenditure and body weight, and to establish whether adiposity affected these responses. Peripheral infusion of TLQP-21 (1mg/kg/day for 7 days) in lean hamsters exposed to short photoperiods (SP) reduced cumulative food intake in the home cage (p<0.05), and intake when measured in metabolic cages (P<0.01). Energy expenditure was significantly increased (p<0.001) by TLQP-21 infusion, this was associated with a significant increase in uncoupling protein 1 mRNA in brown adipose tissue (BAT) (p<0.05), and body weight was significantly reduced (p<0.05). These effects of systemic TLQP-21 treatment were not observed in hamsters exposed to long photoperiod (LP) with a fat phenotype. C3aR1 mRNA and protein were abundantly expressed in the hypothalamus, brown and white adipose tissue in hamsters, but changes in expression cannot explain the differential response to TLQP-21 in lean and fat hamsters.

• Item Type: Articles
• Additional Information: Funding: This work was supported by the British Society of Neuroendocrinology (PHJ; https://www. neuroendo.org.uk/)and Regione Sardegna (RAS) basic research funds CRP-26206 (GLF; https:// www.researchitaly.it/en/home/).
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Stevenson, Professor Tyler
• Authors: Lisci, C., Lewis, J. E., Daniel, Z. C. T. R., Stevenson, T. J., Monnier, C., Marshall, H. J., Fowler, M., Ebling, F. J. P., Ferri, G.-L., Cocco, C., and Jethwa, P. H.
• College/School: College of Medical Veterinary and Life Sciences > School of Biodiversity, One Health & Veterinary Medicine
• Journal Name: PLoS ONE
• Publisher: Public Library of Science
• ISSN: 1932-6203
• ISSN (Online): 1932-6203
• Published Online: 29 August 2019
• Copyright Holders: Copyright © 2019 Lisci et al.
• First Published: First published in PLoS ONE 14(8):e0221517
• Publisher Policy: Reproduced under a Creative Commons license