title: Astrocytic leptin-receptor knockout mice show partial rescue of leptin resistance in diet-induced obesity.
abstract: To determine how astrocytic leptin signaling regulates the physiological response of mice to diet-induced obesity (DIO), we performed metabolic analyses and hypothalamic leptin signaling assays on astrocytic leptin-receptor knockout (ALKO) mice in which astrocytes lack functional leptin receptor (ObR) signaling. ALKO mice and wild-type (WT) littermate controls were studied at different stages of DIO with measurement of body wt, percent fat, metabolic activity, and biochemical parameters. When fed regular chow, the ALKO mice had similar body wt, percent fat, food intake, heat dissipation, respiratory exchange ratio, and activity as their WT littermates. There was no change in blood concentrations of triglyceride, soluble leptin receptor (sObR), mRNA for leptin and uncoupling protein 1 (UCP1) in adipose tissue, and insulin sensitivity. Unexpectedly, in response to a high-fat diet the ALKO mice had attenuated hyperleptinemia and sObR, a lower level of leptin mRNA in subcutaneous fat, and a paradoxical increase in UCP1 mRNA. Thus, ALKO mice did not show the worsening of obesity that occurs with normal WT mice and the neuronal ObR mutation that results in morbid obesity. The findings are consistent with a competing, counterregulatory model between neuronal and astrocytic leptin signaling.
authors: Pennington Biomedical Research Center, Baton Rouge, Louisiana 70808, USA.
authors: Bhavaani
authors: B
authors: Jayaram
authors: Weihong
authors: W
authors: Pan
authors: Yuping
authors: Y
authors: Wang
authors: Hung
authors: H
authors: Hsuchou
authors: Aurelien
authors: A
authors: Mace
authors: Germaine G
authors: GG
authors: Cornelissen-Guillaume
authors: Pramod K
authors: PK
authors: Mishra
authors: Robert A
authors: RA
authors: Koza
authors: Abba J
authors: AJ
authors: Kastin
mesh_terms: D050154:Adiposity; D000818:Animals; D001253:Astrocytes / Q000378:metabolism*; D015415:Biomarkers / Q000097:blood; D001786:Blood Glucose / Q000378:metabolism; D001835:Body Weight; D059305:Diet, High-Fat; D004195:Disease Models, Animal; D004734:Energy Metabolism; D005838:Genotype; D007031:Hypothalamus / Q000378:metabolism*; D007328:Insulin / Q000097:blood; D007473:Ion Channels / Q000235:genetics / Q000378:metabolism; D020738:Leptin / Q000097:blood / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D018345:Mice, Knockout; D024101:Mitochondrial Proteins / Q000235:genetics / Q000378:metabolism; D009043:Motor Activity; D009765:Obesity / Q000097:blood / Q000235:genetics / Q000517:prevention & control*; D010641:Phenotype; D012333:RNA, Messenger / Q000097:blood; D054411:Receptors, Leptin / Q000097:blood / Q000172:deficiency* / Q000235:genetics; D015398:Signal Transduction; D050151:Subcutaneous Fat / Q000378:metabolism; D013997:Time Factors; D014280:Triglycerides / Q000097:blood; D000071256:Uncoupling Protein 1
chemical_list: D015415:Biomarkers; D001786:Blood Glucose; D007328:Insulin; D007473:Ion Channels; D020738:Leptin; D024101:Mitochondrial Proteins; D012333:RNA, Messenger; D054411:Receptors, Leptin; D014280:Triglycerides; C000604372:Ucp1 protein, mouse; D000071256:Uncoupling Protein 1; C515447:leptin receptor, mouse