Aim: To investigate whether lycopene can modulate adiponectin levels and SIRT1 and FoxO1 gene expression in the adipose tissue of diet-induced obese rats. Methods: Male Wistar rats were first fed with hypercaloric diet (HD, n = 12) for 6 weeks, and afterward, these rats were randomly assigned to receive HD ( n = 6) or HD with lycopene-rich tomato oleoresin (equivalent to lycopene 10 mg/kg body weight (BW)/day, HD + L, n = 6) by gavage for additional 6 weeks. Plasma lycopene and adiponectin levels were analyzed by high-performance liquid chromatography and immunoassay, respectively. The messenger RNA (mRNA) expressions of adiponectin, Sirtuin 1 (SIRT1), Forkhead box O 1 (FoxO1), fatty acid translocase/cluster of differentiation 36 (FAT/CD36), and PPARγ in adipose tissues were determined by quantitative polymerase chain reaction. Results: Lycopene was detected in the plasma of rats in HD + L group but not in the HD group. Although both BW and adiposity were not different between the two groups, there was a significant increase in both plasma concentration and mRNA expression of adiponectin in the adipose tissue of the HD + L group. In addition, the lycopene supplementation upregulated mRNA expressions of SIRT1, FoxO1, and FAT/CD36 but downregulated PPARγ in adipose tissue of obese rats. Conclusion: These data suggest that lycopene, in the concentration used, is not toxic and also its health benefits in adipose tissue may play a role against obesity-related complications.

ObjectiveTo evaluate the effect of lycopene supplementation on inflammation in adipose tissue of obese rats.MethodsMale Wistar rats were first fed control diet (C, n=6) or hypercaloric diet (HD, n=12) for 6 wks. Afterwards, the HD rats were randomized into two groups: HD [placebo (corn oil)] or HD+L [lycopene (10 mg/Kg BW/day in corn oil)] by gavage for 6 wks. Plasma lycopene concentration was analyzed by a HPLC system. The mRNA expressions of SIRT1, FoxO1, adiponectin, PPARγ, MCP‐1 and IL‐6 in adipose tissue were determined by real time PCR.ResultsLycopene was detected in plasma (24 nmol/L) from HD+L group only. The mRNA expressions of adiponectin, SIRT1 and FoxO1 decreased significantly but PPARγ, MCP‐1 and IL‐6 increased significantly in adipose tissue from HD group, as compared with those of C group. Although there was no difference in adiposity index between the HD and HD+L group, lycopene supplementation restored the reduced expressions of SIRT1 and FoxO1 to the levels of the C group and inhibited the up‐regulations of PPARγ, MCP‐1 and IL‐6 mRNA expressions in the HD+L group.ConclusionLycopene modulates several key inflammatory genes in adipose tissue indicating its potential protective effect against obesity‐related inflammation.Financial Support: FAPESP (2010/06100–9; 2010/19746–4; 2011/22786–0)