Central leptin versus ghrelin: effects on bone marrow adiposity and gene expression.
This study compared the central effects of ghrelin and leptin on body and bone marrow adiposity and gene expression in adipose tissue and bone marrow. Male Sprague-Dawley rats were injected intracerebroventricular (ICV) twice daily with control, 66 ng ghrelin (G66), 330 ng ghrelin (G330), or 5 μg leptin (L5) for 5 days. Food intake (FI) and body weight (BW) were measured daily. Gene expression in adipose tissue and bone marrow was assessed using RT-PCR. Leptin reduced FI (P < 0.05) and BW (P < 0.05), whereas ghrelin increased BW (P < 0.05) without affecting FI. Leptin decreased fat pad weights, whereas ghrelin (G330) increased fat pad weights (P < 0.05). In epididymal adipose tissue, leptin increased expression of lipolysis marker ADRB2 and thermogenesis marker MFN2 and decreased expression of adipogenic markers, FASN, SLC2A4, and SCD1, whereas ghrelin increased expression of FASN and SCD1. Leptin decreased bone marrow adipocyte size and number; however, ghrelin had no effect on these parameters. In whole bone marrow, leptin decreased expression of FASN and SCD1 and increased expression of DLK1, whereas ghrelin (G330) decreased expression of COL1A1. Thus, leptin induces similar changes in bone marrow and adipose tissue gene expression, reflecting the decreased adiposity in both compartments.
Ambati
Suresh
S
Department of Animal & Dairy Science, University of Georgia, 444 Animal Science Complex, Athens, GA 30602-2771, USA.
Li
Qiang
Q
Rayalam
Srujana
S
Hartzell
Diane L
DL
Della-Fera
Mary Anne
MA
Hamrick
Mark W
MW
Baile
Clifton A
CA
D050156:Adipogenesis; D052436:Adipose Tissue, White / Q000166:cytology / Q000378:metabolism*; D050154:Adiposity; D000818:Animals; D015415:Biomarkers; D001835:Body Weight; D001853:Bone Marrow / Q000378:metabolism*; D001854:Bone Marrow Cells / Q000166:cytology / Q000378:metabolism; D002478:Cells, Cultured; D004032:Diet; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D054439:Ghrelin / Q000008:administration & dosage / Q000502:physiology*; D007276:Injections, Intraventricular; D020738:Leptin / Q000008:administration & dosage / Q000502:physiology*; D008066:Lipolysis; D008297:Male; D012333:RNA, Messenger / Q000378:metabolism; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D022722:Thermogenesis
D015415:Biomarkers; D054439:Ghrelin; D020738:Leptin; D012333:RNA, Messenger