Growing in Antarctica, a challenge for white adipose tissue development in Adelie penguin chicks (Pygoscelis adeliae).

• Published in: American Journal of Physiology-Regulatory, Integrative and Comparative Physiology
• Main Authors: Raccurt, Mireille, Baudimont, Fannie, Tirard, Julien, Rey, Benjamin, Moureaux, Elodie, Géloën, Alain, Duchamp, Claude
• Other Authors: Physiologie intégrative, cellulaire et moléculaire (PICM), Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS), Régulations métaboliques, nutrition et diabètes - UM55 (RMND UM55), Institut National de la Recherche Agronomique (INRA)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National des Sciences Appliquées de Lyon (INSA Lyon), Université de Lyon-Institut National des Sciences Appliquées (INSA)-Institut National des Sciences Appliquées (INSA)-Hospices Civils de Lyon (HCL)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), This work was funded by a grant from the French polar institute (program 131). BR was in receipt of a fellowship from the french Ministère de l'Enseignement Supérieur et de la Recherche.
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2008
• Subjects: adipogenesis; growth; adipocyte; gene expression; white adipose tissue; Adelie penguin; MESH: Adipocytes; MESH: Adipose Tissue; White; MESH: Animals; MESH: Antarctic Regions; MESH: Body Temperature Regulation; MESH: Body Weight; MESH: Cell Differentiation; MESH: DNA Primers; MESH: GATA Transcription Factors; MESH: Gene Expression Profiling; MESH: Organ Size; MESH: RNA; Messenger; MESH: Reverse Transcriptase Polymerase Chain Reaction; MESH: Spheniscidae; MESH: Transcription Factors; MESH: Triiodothyronine; MESH: Aging; [SDV.AEN]Life Sciences [q-bio]/Food and Nutrition; Antarctic; Gata; Antarc*; Antarctica; Pygoscelis adeliae
• Online Access: https://www.hal.inserm.fr/inserm-00322663; https://www.hal.inserm.fr/inserm-00322663/document; https://www.hal.inserm.fr/inserm-00322663/file/Am_J_physiol.pdf; https://doi.org/10.1152/ajpregu.90371.2008

International audience Rapid growth is of crucial importance for Adélie penguin chicks reared during the short Antarctic summer. It partly depends on the rapid ontogenesis of fat stores that are virtually null at hatching but then develop considerably (x40) within a month to constitute both an isolative layer against cold and an energy store to fuel thermogenic and growth processes. The present study was aimed at identifying by RT-PCR the major transcriptional events that chronologically underlie the morphological transformation of adipocyte precursors into mature adipocytes from hatching to 30 days of age. The peak expression of GATA binding protein 3, a marker of preadipocytes, at day 7 posthatch indicates a key proliferation step, possibly in relation to the expression of C/EBPalpha (C/EBPalpha). High plasma total 3,5,3'-triiodo-l-thyronine (T(3)) levels and high levels of growth hormone receptor transcripts at hatching suggested that growth hormone and T(3) play early activating roles to favor proliferation of preadipocyte precursors. Differentiation and growth of preadipocytes may occur around day 15 in connection with increased abundance of transcripts encoding IGF-1, proliferator-activated receptor-gamma, and C/EBPbeta, gradually leading to functional maturation of metabolic features of adipocytes including lipid uptake and storage (lipoprotein lipase, fatty-acid synthase) and late endocrine functions (adiponectin) by day 30. Present results show a close correlation between adipose tissue development and chick biology and a difference in the scheduled expression of regulatory factors controlling adipogenesis compared with in vitro studies using cell lines emphasizing the importance of in vivo approaches.