Effects of dietary fat types on body fatness, leptin, and ARC leptin receptor, NPY, and AgRP mRNA expression.
Some, but not all, fats are obesogenic. The aim of the present studies was to investigate the effects of changing type and amount of dietary fats on energy balance, fat deposition, leptin, and leptin-related neural peptides: leptin receptor, neuropeptide Y (NPY), agouti-related peptide (AgRP), and proopiomelanocortin (POMC), in C57Bl/6J mice. One week of feeding with a highly saturated fat diet resulted in ~50 and 20% reduction in hypothalamic arcuate NPY and AgRP mRNA levels, respectively, compared with a low-fat or an n-3 or n-6 polyunsaturated high-fat (PUFA) diet without change in energy intake, fat mass, plasma leptin levels, and leptin receptor or POMC mRNA. Similar neuropeptide results were seen at 7 wk, but by then epididymal fat mass and plasma leptin levels were significantly elevated in the saturated fat group compared with low-fat controls. In contrast, fat and leptin levels were reduced in the n-3 PUFA group compared with all other groups. At 7 wk, changing the saturated fat group to n-3 PUFA for 4 wk completely reversed the hyperleptinemia and increased adiposity and neuropeptide changes induced by saturated fat. Changing to a low-fat diet was much less effective. In summary, a highly saturated fat diet induces obesity without hyperphagia. A regulatory reduction in NPY and AgRP mRNA levels is unable to effectively counteract this obesogenic drive. Equally high fat diets emphasizing PUFAs may even protect against obesity.
Wang
Hongqin
H
Metabolic Research Center, Department of Biomedical Science, University of Wollongong, Wollongong, New South Wales 2522, Australia.
Storlien
Len H
LH
Huang
Xu-Feng
XF
D000273:Adipose Tissue; D054369:Agouti-Related Protein; D000818:Animals; D001111:Arcuate Nucleus of Hypothalamus / Q000737:chemistry; D001823:Body Composition; D002352:Carrier Proteins / Q000235:genetics*; D004041:Dietary Fats / Q000008:administration & dosage*; D002149:Energy Intake; D015525:Fatty Acids, Omega-3 / Q000008:administration & dosage; D043371:Fatty Acids, Omega-6; D005231:Fatty Acids, Unsaturated / Q000008:administration & dosage; D015870:Gene Expression; D017403:In Situ Hybridization; D036341:Intercellular Signaling Peptides and Proteins; D020738:Leptin / Q000097:blood*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009478:Neuropeptide Y / Q000235:genetics*; D011333:Pro-Opiomelanocortin / Q000235:genetics; D011506:Proteins / Q000235:genetics*; D012333:RNA, Messenger / Q000032:analysis; D011956:Receptors, Cell Surface; D054411:Receptors, Leptin
D054369:Agouti-Related Protein; D002352:Carrier Proteins; D004041:Dietary Fats; D015525:Fatty Acids, Omega-3; D043371:Fatty Acids, Omega-6; D005231:Fatty Acids, Unsaturated; D036341:Intercellular Signaling Peptides and Proteins; D020738:Leptin; D009478:Neuropeptide Y; D011506:Proteins; D012333:RNA, Messenger; D011956:Receptors, Cell Surface; D054411:Receptors, Leptin; C515447:leptin receptor, mouse; D011333:Pro-Opiomelanocortin