White Pulp Expansion of the Spleen is correlated with Plasma IL‐6 and Glucose in Mice Fed High‐Fat, High‐Sugar Diet

Abstract

We previously identified significant splenomegaly in mice fed a diet high in fat and sugar (HFSD) in comparison to mice fed a standard diet. Mice fed HFSD also exhibited elevated blood plasma levels of glucose and the proinflammatory cytokine IL‐6. However, the relationship between these markers and the proliferation of immune tissue in the spleen is unclear. The white pulp of the spleen is a site of immune response and may expand when exposed to proinflammatory signaling molecules. In this study, we investigated the correlations among splenic white pulp area, plasma glucose, and plasma IL‐6. Female C57BL/6 mice aged 6 weeks were randomly divided into lean control (n=4) and HFSD (n=4) groups. HFSD consisted of chow with 60% fat content and drinking water with 42 g/L sugar (55% sucrose, 45% fructose). Treatment was administered for 12 weeks. White pulp area of the spleen was measure from histological sections stained with H&E. Mice in the HFSD group became significantly obese and hyperglycemic by the end of the study (P < 0.05). Mice fed HFSD also had significantly larger splenic white pulps than lean mice (P < 0.05). Splenic white pulp area was positively correlated with blood plasma levels of IL‐6 (r = 0.725, P < 0.05) and glucose (r = 0.686, P < 0.05). Plasma Il‐6 was also positively correlated with plasma glucose levels (r = 0.887, P < 0.01). These data support the hypothesis that HFSD is associated with histological expansion of the white pulp of the spleen that correlates with diet‐induced hyperglycemia and the expression of proinflammatory cytokines.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.