Fig. 1.

(A) Weight is increased on a high-fat diet by 13 weeks on diet. Mice were started on a high-fat diet at weaning at 3 weeks of age. Overall groups were significantly different (^*** p < 0.001 by two-way ANOVA), subgroups were different at 13 to 15 weeks and 21 to 24 weeks of age (Sidak’s multiple comparison posttests, ^*** p < 0.001 for each). (B) Relative Cyp2r1 liver mRNA abundance is decreased on high-fat diet. Relative abundance of Cyp2r1 mRNA and Nono mRNA were determined by digital droplet quantitative PCR, and Cyp2r1 was normalized to Nono abundance in each sample. Overall groups were different (^*** p < 0.001 by two-way ANOVA), subgroups were different at 6, 13 to 15, and 21 to 24 weeks of age (Sidak’s multiple comparison post-tests, * p < 0.05 at 6 weeks, ^*** p < 0.001 at 13 to 15 and 21 to 24 weeks). (C) Serum 25(OH)D is decreased in parallel with Cyp2R1 mRNA abundance on high-fat diet. Serum 25(OH)D was determined by LC/MS/MS. Overall groups were different (* p < 0.01 by two-way ANOVA), subgroups were different at 13 to 15 and 21 to 24 weeks of age (Sidak’s multiple comparison post-tests, * p < 0.05 at 6 weeks, 13 to 15 weeks, and 21 to 24 weeks). (D) Relative liver Cyp3a11 abundance was not decreased on a high-fat diet. mRNA abundance was determined by digital droplet quantitative PCR and normalized to Nono. Transcript levels did not differ significantly between chow and high-fat diet fat groups (p > 0.05 by t test). (E) Relative liver Cyp27a1 abundance was not decreased on a high-fat diet. mRNA abundance was determined by digital droplet quantitative PCR and normalized to Nono. Transcript levels did not differ significantly between chow and high-fat diet fat groups (p > 0.05 by t test). (F) Relative liver Cyp24a1 abundance was not decreased on a high-fat diet. mRNA abundance was determined by digital droplet quantitative PCR and normalized to Nono. Transcript levels did not differ significantly between chow and high-fat diet fat groups (p > 0.05 by t test).