Short term consumption of lycopene and phytofluene decreases PPARα and PPARγ expression in selected rat tissues

Abstract

Peroxisome proliferator‐activated receptor γ (PPARγ) is a nuclear hormone receptor that plays a key role in adipocyte differentiation. PPARα belongs to the same nuclear receptor family and regulates genes involved in fatty acid oxidation. Previously, we had shown that lycopene (LYC) feeding decreased expression of PPARγ and its target gene, fatty acid binding protein 3 (FABP3), in selected rat tissues. To evaluate the effects of phytofluene (PF), LYC or tomato powder (TP) consumption and androgen status on PPARγ and PPARα expression, 8 wk old male Fisher 344 rats were castrated or sham‐operated and subsequently provided with oral supplementation of PF or LYC (~0.7 mg/d) or fed a 10% tomato powder or control diet (AIN‐93G) for 4 days. In the liver of intact rats, PF and LYC decreased expression of PPARα and its target gene CYP 4A2. PF, LYC, and TP also reduced PPARγ expression in the adipose tissue of intact rats. Carotenoid monooxygenase I (CMO I), a PPARγ target gene, followed PPARγ expression patterns in various tissues. CMO II appeared to remain constitutively active. These results suggest a possible role of phytofluene and lycopene in lipid metabolism via modulation of PPARγ and PPARα expression. (Funded in part by NIH/NCI CA 112649‐01A1)