Abstract Objectives The objective of this work was to investigate the effects of dietary supplementation of purified lycopene (LYC) or a source of LYC as in tomato powder (TP) on live hen performance, egg yolk cholesterol concentrations as well as the gene expressions related to mechanism and regulation of cholesterol, namely Niemann-Pick C1-like 1 protein (NPC1L1), acyl-CoA: cholesterol acyltransferase 2 (ACAT2), microsomal triacylglycerol transport protein (MTP), ATP binding cassette transporters sub-family G member 5 and 8 (ABCG5/8), ATP citrate lyase (ACLY), liver X receptor alpha (LXRα) and sterol regulatory element-binding proteins (SREBP1c). Methods A total of 150 20-week-old white laying hens were divided into one of 3 treatments, with 10 replicates of 5 hens per cage, totaling 50 hens per treatment. The birds were fed either a basal diet (Control) or basal diet supplemented with 20 mg purified lycopene/kg diet (LYC) or an equal amount of lycopene-containing tomato powder (TP) for 12 weeks. Results Feed intake, egg production and feed conversion ratio remained similar among treatments (P ≥ 0.27). However, egg weights from hens fed a diet supplemented with lycopene particularly the purified form were greater (P = 0.036). Supplementing lycopene either purified or as in TP increased the concentrations of serum and egg yolk lycopene but decreased serum and egg yolk cholesterol concentrations (P < 0.001). Supplementing LYC purified or as in TP decreased the gene expression of intestinal NPC1L1, MTP, ACAT2, hepatic SREBP1c, ACLY, and LXRα but increased hepatic ABCG5 and ABCG8 (P < 0.001). The gene expressions were more pronounced with TP supplements compared with that of the LYC supplements. Conclusions The results of the present work revealed that egg yolk cholesterol metabolism is downregulated through decreased activities of intestinal NPC1L1, MTP, ACAT2, hepatic SREBP1c, ACLY, and LXRα but upregulated with increased hepatic activities of ABCG5 and ABCG8. Funding Sources Small and Medium Enterprises Development Organization of Turkey (KOSGEB) Turkish Academy of Sciences.
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