Figure 5: Putative Role of Thyroid Receptor Beta Antagonism in Dust Extract-Induced Adipogenic Activity.
Putative interrogation of thyroid receptor beta (TRβ) antagonism as a molecular mechanism promoting triglyceride accumulation. (A) Normalized triglyceride accumulation per cell relative to maximal intra-assay response for rosiglitazone (normalized to DNA content) for 1–850, a TR antagonist. 3T3-L1 cells were induced to differentiate as described in Methods and assessed for degree of adipocyte differentiation after ten days of differentiation. * denotes the lowest concentration at which a significant increase above baseline values (differentiated DMSO control) was observed. (B) Spearman’s correlation comparing normalized triglyceride accumulation per cell relative to maximal intra-assay response for rosiglitazone (normalized to DNA content) versus TRβ antagonism as measured via GeneBLAzer TRβ FRET reporter assay (Invitrogen) (Kollitz et al. 2018). Significant correlations were determined with p < 0.05 using GraphPad Prism 7.0. (C) Box and whisker plots depicting normalized triglyceride accumulation per cell (normalized to DNA content) in each tertile of maximal TRβ antagonism (low/medium/high antagonist activities). **denotes significant differences between groups as per Kruskal-Wallis test, p<0.001, using GraphPad Prism 7.0.