title: Energy metabolism in human renin-gene transgenic rats: does renin contribute to obesity?
abstract: Renin initiates angiotensin II formation and has no other known functions. We observed that transgenic rats (TGR) overexpressing the human renin gene (hREN) developed moderate obesity with increased body fat mass and glucose intolerance compared with nontransgenic Sprague-Dawley (SD) rats. The metabolic changes were not reversed by an angiotensin-converting enzyme inhibitor, a direct renin inhibitor, or by (pro)renin receptor blocker treatment. The obese phenotype in TGR(hREN) originated from higher food intake, which was partly compensated by increases in resting energy expenditure, total thermogenesis (postprandial and exercise activity), and lipid oxidation during the first 8 weeks of life. Once established, the difference in body weight between TGR(hREN) and SD rats remained constant over time. When restricted to the caloric intake of SD, TGR(hREN) developed an even lower body weight than nontransgenic controls. We did not observe significant changes in the cocaine and amphetamine-regulated transcript, pro-opiomelanocortin, both anorexigenic, or neuropeptide Y, orexigenic, mRNA levels in TGR(hREN) versus SD controls. However, the mRNA level of the agouti-related peptide, orexigenic, was significantly reduced in TGR(hREN) versus SD controls at the end of the study, which indicates a compensatory mechanism. We suggest that the human renin transgene initiates a process leading to increased and early appetite, obesity, and metabolic changes not related to angiotensin II. The mechanisms are independent of any currently known renin-related effects.
authors.affiliation: Franz Volhard Clinical Research Center, HELIOS Klinikum Berlin-Buch, Berlin-Buch, Germany.
authors.forename: Petra
authors.initials: P
authors.lastname: Gratze
authors.forename: Michael
authors.initials: M
authors.lastname: Boschmann
authors.forename: Ralf
authors.initials: R
authors.lastname: Dechend
authors.forename: Fatimunnisa
authors.initials: F
authors.lastname: Qadri
authors.forename: Jeanette
authors.initials: J
authors.lastname: Malchow
authors.forename: Sabine
authors.initials: S
authors.lastname: Graeske
authors.forename: Stefan
authors.initials: S
authors.lastname: Engeli
authors.forename: Jürgen
authors.initials: J
authors.lastname: Janke
authors.forename: Jochen
authors.initials: J
authors.lastname: Springer
authors.forename: Aurelie
authors.initials: A
authors.lastname: Contrepas
authors.forename: Ralph
authors.initials: R
authors.lastname: Plehm
authors.forename: Susanne
authors.initials: S
authors.lastname: Klaus
authors.forename: Genevieve
authors.initials: G
authors.lastname: Nguyen
authors.forename: Friedrich C
authors.initials: FC
authors.lastname: Luft
authors.forename: Dominik N
authors.initials: DN
authors.lastname: Muller
mesh_terms: D017667:Adipocytes / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D000577:Amides / Q000494:pharmacology; D000804:Angiotensin II / Q000378:metabolism*; D000818:Animals; D002478:Cells, Cultured; D004195:Disease Models, Animal; D004734:Energy Metabolism / Q000502:physiology*; D005650:Fumarates / Q000494:pharmacology; D006801:Humans; D020738:Leptin / Q000097:blood; D050356:Lipid Metabolism / Q000502:physiology; D008297:Male; D009765:Obesity / Q000378:metabolism*; D010641:Phenotype; D051381:Rats; D017207:Rats, Sprague-Dawley; D055647:Rats, Transgenic; D012083:Renin / Q000235:genetics / Q000378:metabolism*; D022722:Thermogenesis / Q000502:physiology; D000092502:Renin Inhibitors
chemical_list: D000577:Amides; D000804:Angiotensin II; D005650:Fumarates; D020738:Leptin; D012083:Renin; D000092502:Renin Inhibitors; C446481:aliskiren