Figure 3.

Heparan sulfate deficiency during adipogenesis promotes fatty acid oxidation. A, WT cells produce a greater amount of lactate than Ndst1^−/− adipocytes or adipocytes treated with heparin (100 μg/ml) during differentiation, as observed by discoloration of the phenol red indicator on day 6 of the differentiation over a 48-h period. B, YSI measurement of lactate in spent media collected on the final day (day 6) of adipogenesis. Fresh media have a concentration of 1.5 mmol/L lactate on day 6 of the differentiation over a 48-h period. (two-way ANOVA, n = 2, one representative experiment out of 3). C, YSI measurement of glucose in spent media collected on the final day (day 6) of adipogenesis over a 48-h period, with fresh media at a concentration of 19 mmol/L glucose (two-way ANOVA, n = 2, one representative experiment out of three). D, palmitate abundance relative to control WT cells from saponified lipids measured using mass spectroscopy, indicating total intracellular palmitate is higher in WT control cells (two-way ANOVA, n = 3). E, intracellular [U-¹³C₁₆] palmitate levels indicate that HSPG-inhibited conditions present with increased palmitate uptake compared to control WT adipocytes (two-way ANOVA, n = 3). F, tracing of [U-¹³C₁₆] palmitate metabolism indicates that palmitate is being increasingly converted to citrate in HSPG-inhibited adipocytes compared to control WT controls (Two-way ANOVA, n = 3). Data are presented as mean ± SD, ∗∗∗p < 0.001, ∗∗∗∗p <0.0001. HSPG, HS proteoglycan; Ndst1, N-deacetylase-N-sulfotransferase 1.