Mice With a Deletion in the Gene for CCAAT/Enhancer-Binding Protein β Are Protected Against Diet-Induced Obesity

Department of Nutrition, Case Western Reserve University, Cleveland, OH 44106, USA.
Diabetes (Impact Factor: 8.1). 02/2007; 56(1):161-7. DOI: 10.2337/db06-0310
Source: PubMed


The CCAAT/enhancer-binding protein beta (C/EBPbeta) is required for adipocyte differentiation and maturation. We have studied the role of the transcription factor, C/EBPbeta, in the development of diet-induced obesity. Mice with a deletion in the gene for C/EBPbeta (C/EBPbeta(-/-)) and wild-type mice were fed a high-fat diet (60% fat) for 12 weeks. The C/EBPbeta(-/-) mice lost body fat, whereas the wild-type mice increased their total body fat on a high-fat diet. The C/EBPbeta(-/-) mice had lower levels of blood triglycerides, free fatty acids, cholesterol, and hepatic triglyceride accumulation compared with the wild-type mice, thus protecting them from diet-induced obesity and fatty liver on a high-fat diet. Deletion of C/EBPbeta gene resulted in greatly reducing hepatic lipogenic genes, acetyl CoA carboxylase, and fatty acid synthase and increasing the expression of beta-oxidation genes in the brown adipose tissue. CO(2) production was significantly higher in the C/EBPbeta(-/-) mice as was the level of uncoupling protein (UCP)-1 and UCP-3 in the muscle. In conclusion, the transcription factor C/EBPbeta is an important regulator in controlling lipid metabolism and in the development of diet-induced obesity.

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    • "Phenotype/influence Transcription factors Signaling factors/receptors Growth fac- tors/hormones/cytokines Metabolism/apolipoproteins Adipose tissue development C/EBP˛, -ˇ, -ı (Arch, 2002; Bluher, 2005; Millward et al., 2007 "
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