Serum and inguinal white adipose tissue levels of β-carotene, retinoids and apocarotenoids.

(A, B) β-carotene -15, 15′-monoxygenase (Bcmo1) and β-carotene 9′, 10′-dioxygenase (Bcdo2) mRNA levels in inguinal white adipose tissue (iWAT) of wild-type (WT) and Bcmo1-null (Bcmo1^-/-) mice after 14 weeks on a control diet (open bars) or a β-carotene-enriched diet (black bars). Quantitative real-time PCR was used to determine normalized gene expression levels. (C-G) β-carotene, retinol and 10′ β-apocarotenol levels in serum and iWAT of WT and Bcmo1^-/- mice after 14 weeks on a control diet (open bars) or a β-carotene-enriched diet (black bars). β-carotene, retinol and β-10′-apocarotenol were determined by HPLC (see Materials and Methods). Total retinol refers to free retinol plus retinyl esters. Data in (A to G) are the mean ± SEM of 6 animals per group; n.d. non-detectable; GxD, interaction between genotype and diet in two-way ANOVA analysis (p<0.05); G, genotype effect in two-way ANOVA analysis (p<0.05); *, p<0.05 in Student's t test, BC diet versus control diet.