Scope: Several studies have linked the high intake of lycopene or tomatoes products with lower risk for metabolic diseases. The aim of the present study was to evaluate and to compare the effect of lycopene and tomato powder on obesity associated disorders. Methods and results:Male C57BL/J6 mice were assigned into 4 groups to receive: control diet (CD), high fat diet (HFD), high fat diet supplemented with lycopene or with tomato powder (TP) for 12 weeks. In HFD condition, lycopene and TP supplementation significantly reduced adiposity index, organ and relative organ weights, serum triglycerides, free fatty acids, 8-iso-prostaglandin GF2α and improved glucose homeostasis, but did not affect total body weight. Lycopene and TP supplementation prevented HFD-induced hepatosteatosis and hypertrophy of adipocytes. Lycopene and TP decreased HFD-induced pro-inflammatory cytokine mRNA expression in the liver and in the epididymal adipose tissue. The antiinflammatory effect of lycopene and TP was related to a reduction in the phosphorylation levels of IκB, and p65, and resulted in a decrease of inflammatory proteins in adipose tissue Conclusion:These results suggest that lycopene or TP supplementation display similar beneficial health effects that could be particularly relevant in the context of nutritional approaches to fight obesity-associated pathologies.

Scope Although about 90% of lycopene in dietary sources occurs in the linear all‐trans conformation, a large proportion of the lycopene found in human tissues is of the cis‐isomer type, notably (5Z)‐lycopene. The biological effects of this (5Z) isomer have been under‐researched. The aim of this study is to evaluate some biological functions of (5Z)‐lycopene in adipocytes and to compare them with those of (all‐E)‐lycopene. Methods and results (all‐E)‐ and (5Z)‐Lycopene displayed strong similarities in global gene expression profile and biological pathways impacted. Peroxisome proliferator‐activated receptor (PPAR) signaling is identified as a major actor mediating the effects of lycopene isomers. Transactivation assays confirmed the ability of both isomers to transactivate PPARγ. In addition, the TNFα‐induced proinflammatory cytokine mRNA expression in 3T3‐L1 adipocytes is reduced by both isomers via a reduction in the phosphorylation levels of p65. Finally, lycopene isomers restore the TNF‐α‐blunted uptake of glucose by adipocytes via a modulation of AKT phosphorylation. Conclusion These results show that lycopene isomers exert similar biological functions in adipocytes, linked to their ability to transactivate PPARγ. These findings add to our knowledge of lycopene effects in adipocyte biology and point to the possible use of lycopene in the prevention of obesity‐related disorders.

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