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Wildtype Mouse Hypothalamus Cerebellum Fed Fast

ABSTRACT: The hypothalamus is a key site for the integration of the response to nutrient deprivation in higher organisms. Transcripts that are dynamically regulated in the hypothalamus by feeding and fasting are likely to play a regulatory role in energy balance. In order to identify hypothalamic genes whose expression is altered by fasting, we compared the transcriptomes of hypothalamic blocks from freely feeding vs overnight fasted mice using whole genome oligonucleotide arrays. In order to exclude changes due to non-specific neuronal stress responses to energy deprivation we simultaneously profiled the cerebellum, a brain site with no known regulatory role in energy balance. The power of this approach was illustrated by the fact that while we confirmed previous observations that the Sulfotransferase family 1A gene is upregulated by fasting in the hypothalamus, we showed that it was similarly upregulated in the cerebellum and is therefore unlikely to be specifically involved in the regulation of energy balance. In contrast, using three different methods of pathway enrichment analysis, multiple genes involved in mitochondrial oxidative phosphorylation were found to be co-ordinately downregulated by fasting in the hypothalamus but not in the cerebellum. These findings suggest that a switch from oxidative to non-oxidative metabolism in the hypothalamus may be an important element of the homeostatic response to nutrient deprivation. Keywords: hypothalamus, cerebellum, fasting, appetite, obesity

ORGANISM(S): Mus musculus

PROVIDER: GSE4221 | GEO | 2007/02/09

SECONDARY ACCESSION(S): PRJNA94863

REPOSITORIES: GEO

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Wildtype Mouse Hypothalamus Cerebellum Fed Fast

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