Dietary effects of arachidonate-rich fungal oil and fish oil on murine hepatic and hippocampal gene expression

Lipids in Health and Disease

Matthew A Roberts³  J Bruce German⁴  David M Mutch¹  Alvin Berger² 

[1] Institut de Biologie Animale, Université de Lausanne, CH-1015 Lausanne, Switzerland;Current Address: Cytochroma, Inc., Manager Lipidomics™, 330 Cochrane Drive, Markham, Ontario, Canada;Metabolic and Genomic Regulation, Nestlé Research Center, Vers-chez-les-Blanc, CH-1000 Lausanne 26, Switzerland;Department of Food Science, University of California, Davis, CA 95616, USA

关键词: transcription;    SREBP;    PPAR;    microarray;    mice;    liver;    hippocampus;    fatty acid;    docosahexaenoic acid;    arachidonic acid;   

Others  :  1213332
DOI  :  10.1186/1476-511X-1-2

 received in 2002-10-10, accepted in 2002-10-21,  发布年份 2002

【 摘 要 】

Background

The functions, actions, and regulation of tissue metabolism affected by the consumption of long chain polyunsaturated fatty acids (LC-PUFA) from fish oil and other sources remain poorly understood; particularly how LC-PUFAs affect transcription of genes involved in regulating metabolism. In the present work, mice were fed diets containing fish oil rich in eicosapentaenoic acid and docosahexaenoic acid, fungal oil rich in arachidonic acid, or the combination of both. Liver and hippocampus tissue were then analyzed through a combined gene expression- and lipid- profiling strategy in order to annotate the molecular functions and targets of dietary LC-PUFA.

Results

Using microarray technology, 329 and 356 dietary regulated transcripts were identified in the liver and hippocampus, respectively. All genes selected as differentially expressed were grouped by expression patterns through a combined k-means/hierarchical clustering approach, and annotated using gene ontology classifications. In the liver, groups of genes were linked to the transcription factors PPARα, HNFα, and SREBP-1; transcription factors known to control lipid metabolism. The pattern of differentially regulated genes, further supported with quantitative lipid profiling, suggested that the experimental diets increased hepatic β-oxidation and gluconeogenesis while decreasing fatty acid synthesis. Lastly, novel hippocampal gene changes were identified.

Conclusions

Examining the broad transcriptional effects of LC-PUFAs confirmed previously identified PUFA-mediated gene expression changes and identified novel gene targets. Gene expression profiling displayed a complex and diverse gene pattern underlying the biological response to dietary LC-PUFAs. The results of the studied dietary changes highlighted broad-spectrum effects on the major eukaryotic lipid metabolism transcription factors. Further focused studies, stemming from such transcriptomic data, will need to dissect the transcription factor signaling pathways to fully explain how fish oils and arachidonic acid achieve their specific effects on health.

【 授权许可】

   
2002 Berger et al; licensee BioMed Central Ltd. This is an Open Access article: verbatim copying and redistribution of this article are permitted in all media for any purpose, provided this notice is preserved along with the article's original URL.

【 图 表 】

Figure 1.

Figure 2.

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