| Autor: |
McAllan L; Department of Pediatrics, University of Tennessee Health Science Center , Memphis, Tennessee.; Children's Foundation Research Institute, Le Bonheur Children's Hospital , Memphis, Tennessee., Maynard KR; Lieber Institute for Brain Development, Johns Hopkins Medical Campus, Baltimore, Maryland., Kardian AS; Lieber Institute for Brain Development, Johns Hopkins Medical Campus, Baltimore, Maryland., Stayton AS; Department of Pediatrics, University of Tennessee Health Science Center , Memphis, Tennessee.; Children's Foundation Research Institute, Le Bonheur Children's Hospital , Memphis, Tennessee., Fox SL; Department of Pediatrics, University of Tennessee Health Science Center , Memphis, Tennessee.; Children's Foundation Research Institute, Le Bonheur Children's Hospital , Memphis, Tennessee., Stephenson EJ; Department of Pediatrics, University of Tennessee Health Science Center , Memphis, Tennessee.; Children's Foundation Research Institute, Le Bonheur Children's Hospital , Memphis, Tennessee., Kinney CE; Department of Pediatrics, University of Tennessee Health Science Center , Memphis, Tennessee.; Children's Foundation Research Institute, Le Bonheur Children's Hospital , Memphis, Tennessee., Alshibli NK; Department of Pediatrics, University of Tennessee Health Science Center , Memphis, Tennessee., Gomes CK; Department of Pediatrics, University of Tennessee Health Science Center , Memphis, Tennessee.; Children's Foundation Research Institute, Le Bonheur Children's Hospital , Memphis, Tennessee., Pierre JF; Department of Pediatrics, University of Tennessee Health Science Center , Memphis, Tennessee.; Children's Foundation Research Institute, Le Bonheur Children's Hospital , Memphis, Tennessee., Puchowicz MA; Department of Pediatrics, University of Tennessee Health Science Center , Memphis, Tennessee.; Children's Foundation Research Institute, Le Bonheur Children's Hospital , Memphis, Tennessee., Bridges D; Department of Pediatrics, University of Tennessee Health Science Center , Memphis, Tennessee.; Children's Foundation Research Institute, Le Bonheur Children's Hospital , Memphis, Tennessee.; Department of Physiology, University of Tennessee Health Science Center , Memphis, Tennessee., Martinowich K; Lieber Institute for Brain Development, Johns Hopkins Medical Campus, Baltimore, Maryland.; Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine , Baltimore, Maryland.; Department of Neuroscience, Johns Hopkins University School of Medicine , Baltimore, Maryland., Han JC; Department of Pediatrics, University of Tennessee Health Science Center , Memphis, Tennessee.; Children's Foundation Research Institute, Le Bonheur Children's Hospital , Memphis, Tennessee.; Department of Physiology, University of Tennessee Health Science Center , Memphis, Tennessee. |
| Abstrakt: |
Brain-derived neurotrophic factor (BDNF) is a key neuropeptide in the central regulation of energy balance. The Bdnf gene contains nine promoters, each producing specific mRNA transcripts that encode a common protein. We sought to assess the phenotypic outcomes of disrupting BDNF production from individual Bdnf promoters. Mice with an intact coding region but selective disruption of BDNF production from Bdnf promoters I, II, IV, or VI (Bdnf-e1 -/- , -e2 -/- , -e4 -/- , and -e6 -/- ) were created by inserting an enhanced green fluorescent protein-STOP cassette upstream of the targeted promoter splice donor site. Body composition was measured by MRI weekly from age 4 to 22 wk. Energy expenditure was measured by indirect calorimetry at 18 wk. Food intake was measured in Bdnf-e1 -/- and Bdnf-e2 -/- mice, and pair feeding was conducted. Weight gain, lean mass, fat mass, and percent fat of Bdnf-e1 -/- and Bdnf-e2 -/- mice (both sexes) were significantly increased compared with wild-type littermates. For Bdnf-e4 -/- and Bdnf-e6 -/- mice, obesity was not observed with either chow or high-fat diet. Food intake was increased in Bdnf-e1 -/- and Bdnf-e2 -/- mice, and pair feeding prevented obesity. Mutant and wild-type littermates for each strain (both sexes) had similar total energy expenditure after adjustment for body composition. These findings suggest that the obesity phenotype observed in Bdnf-e1 -/- and Bdnf-e2 -/- mice is attributable to hyperphagia and not altered energy expenditure. Our findings show that disruption of BDNF from specific promoters leads to distinct body composition effects, with disruption from promoters I or II, but not IV or VI, inducing obesity. |
