High fat diets enriched in n‐3 polyunsaturated fatty acids do not suppress B cell activation but increase spleen size and accumulation of adipose tissue and lower liver triglycerides

• Published in: The FASEB Journal
• Main Authors: Shaikh, Saame Raza, Carraway, Kristen, Rockett, Benjamin Drew
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2010
• Subjects: eskimo*
• Online Access: http://dx.doi.org/10.1096/fasebj.24.1_supplement.723.7

N‐3 polyunsaturated fatty acids (PUFA) suppress T cell activation; however far less is known about the effects of the fatty acids on activation of B cells. Here we tested the hypothesis that n‐3 PUFAs could suppress B220 B cell activation in response to LPS in vitro and ex vivo. In vitro, eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids did not suppress B cell activation, although DHA did lower IL‐6 levels. In addition, EPA and DHA prevented palmitate induced lipid overload which was driven by accumulation of the fatty acids into the membranes of B cells. Ex vivo, a high fat diet enriched in n‐3 PUFAs, which modeled intake of n‐3 PUFAs in Eskimos, had no effect on mouse splenic B cell activation. During the course of the study, unexpectedly, n‐3 PUFAs increased spleen size and body weight gain compared to low fat and other high fat diets. The increase in body weight was due to accumulation of brown, inguinal, and epididymal fat. The high fat n‐3 PUFA diet did lower triglyceride accumulation in the liver, consistent with the in vitro studies. Taken together, our data show that n‐3 PUFAs do not suppress B cell activation. More importantly, a high fat diet in n‐3 PUFAs can increase body fat but lower liver triglycerides.