Intrinsic Properties of Brown and White Adipocytes Have Differential Effects on Macrophage Inflammatory Responses

Figure 2

Differential effects of brown and white adipocytes on IL-6 secretion. Preadipocytes were cultured for 24 hours prior to differentiation for 10 days as described in Section 2. Differentiated adipocytes grown on transwell inserts were then cocultured for an additional 24 hours with differentiated macrophages grown on transwell plates. After 12 days, IL-6 secretion was measured from conditioned media from adipocytes. (a) White adipocyte shows significantly more IL-6 secretion than brown adipocytes. Bar graphs represent mean + SEM of biological replicates of the same adipocyte clone cultured in a separate well. Student’s t-test, . After macrophages were differentiated, cells were either left untreated (resting state) or treated with LPS/IFNγ or IL-4 for 24 hours. Media with stimuli were removed and cells were then washed prior to coculture with or without adipocytes that were differentiated as described in Section 2. ((b) and (c)) Coculture of macrophages with white adipocytes significantly increases IL-6 secretion compared to monoculture of macrophage alone and when cocultured with brown adipocyte in both U937 (b) and THP-1 (c) macrophages in culture conditions of macrophages that were previously at rest or stimulated with LPS/IFNγ and IL-4 for 24 hours. Bar graphs represent mean + SEM of biological replicates of cultures grown in separate wells. for macrophage monoculture, for macrophages cocultured with white adipocytes of the same clone, and for macrophages cocultured with brown adipocytes of the same clone. Two-way ANOVA followed by Tukey’s post hoc test for multiple comparisons. , , and compared to monoculture. ⁺⁺ and ⁺⁺⁺⁺ white versus brown coculture.

(a)

(b)

(c)