Differences in adipose tissue inflammation and oxidative status in C57BL/6 and ApoE-/- mice fed high fat diet.

Atherosclerosis and Nutritional Biochemistry Laboratory, Biochemistry and Immunology Department - Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil.
Animal Science Journal (Impact Factor: 1.04). 07/2012; 83(7):549-55. DOI: 10.1111/j.1740-0929.2011.00982.x
Source: PubMed

ABSTRACT Apolipoprotein E deficient (Apo E-/-) mice are more resistant to the development of obesity compared to C57BL/6 wild type mice. They also hold a high basal oxidative status due to the loss of antioxidant action of apolipoprotein E. Since obesity is also an inducer of inflammation, we studied the effect of high-fat diet on obesity and oxidative stress in C57BL/6 and Apo E-/- mice for 9 weeks. The results confirmed that Apo E-/- mice fed high-fat diet are more resistant to the increase of both body weight and adiposity compared to C57BL/6 mice. Despite this, Apo E-/- mice presented a higher basal oxidative stress that was enhanced by high-fat diet. Macrophage infiltration, macrophage forming crown-like structures and proinflammatory adipokines (interleukin 6 and tumor necrosis factor alpha) were all higher in adipose tissue from Apo E-/- compared to C57BL/6 mice, regardless of diet type. In conclusion, although Apo E-/- mice are more resistant to becoming obese, they develop more severe adipose tissue inflammation companied by its consequences.

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