Developmental and Functional Heterogeneity of White Adipocytes within a Single Fat Depot (2018)
Figure 4

Figure 4. Adipocyte subtypes exhibit differential phenotypic characteristics and signaling in response to exogenous stimuli.

A) Triglyceride content of cell cultures after six days of differentiation using the protocol described in Methods. Data are shown as mean ± SEM of 3-7 samples, and the entire experiment was repeated twice.

B) [3H]-labeled 2-deoxyglucose uptake in preadipocyte cell lines in the basal state and after pretreatment for 20 minutes with 100 nM insulin. Uptake was measured for one hour, and data are shown as mean ± SEM of 3-7 samples and repeated twice.

C) [3H]-labeled 2-deoxyglucose uptake in adipocytes after six days of adipogenic differentiation in the basal state and after stimulation for 20 minutes with 100 nM insulin. Uptake was measured for one hour, and data are shown as mean ± SEM of 3-7 samples. The experiment was repeated twice.

D) [14C] D-glucose incorporation into lipids in adipocytes after six days of adipogenic differentiation in the basal state and after stimulation for 20 minutes with 100 nM insulin. [14C] D-glucose incorporation was measured after three hours, and data are shown as mean ± SEM of 3-7 samples. The experiment was repeated twice.

E) Lipolysis rates after stimulation with 1 nM isoproterenol as measured by glycerol release from adipocytes after six days of adipogenic differentiation. Data are shown as mean ± SEM of 3-7 replicates and normalized by lipid content of the cells. The entire experiment was repeated twice.

F) Extracellular acidification rate (ECAR) of preadipocytes and adipocytes after 4 days of in vitro differentiation was determined by calculating the area under the curve (AUC) during measurements of basal respiration. The whole experiment was repeated three times. Data are shown as mean ± SEM of 3-7 cell lines per group.

G) Basal respiration of preadipocytes and adipocytes after 4 days of in vitro differentiation was determined by calculating the area under the curve (AUC) during measurements of oxygen consumption rate (OCR). The whole experiment was repeated three times. Data are shown as mean ± SEM of 3-7 cell lines per group.

H) Ratio of oxygen consumption rate (OCR) to extracellular acidification rate (ECAR) of preadipocytes and adipocytes after 4 days of in vitro differentiation. Data are shown as mean ± SEM of 3-7 cell lines per group.

I) Representative Western blot analysis of three independent adipocyte cell lines after 6 days of in vitro differentiation for: pJnk T183/Y185 and total Jnk after treatment with 10 nM TNFα for 15 minutes (Inflammation); pAkt S473 and total Akt after treatment with 100 nM insulin for 15 minutes (Insulin Signaling); pStat5 Y694 and total Stat5 after treatment with 500 nM GH for 20 minutes (Growth Hormone).

Data information: Bars indicate significant differences between groups (p<0.05; two‐way ANOVA) in all panels. In panels (C-E) asterisks indicate significant differences between basal and treated samples (p<0.05; Student's t‐test). In panels (F-H) asterisks indicate significant differences between preadipocytes and adipocytes (p<0.05; Student's t‐test).