Caenorhabditis elegans as a model to study the effectiveness and metabolic targets of dietary supplements used for obesity treatment: the specific case of a conjugated linoleic acid mixture (Tonalin).

The antiobesity effect of conjugated linoleic acid (CLA) has previously been described in different animal models. The aim of the present study was to investigate the effect of a commercial mixture (Tonalin) on Caenorhabditis elegans to assess their potential use for functional ingredient screenings. Body-fat reduction with Tonalin was demonstrated in wild-type strain N2. The 1 μg/mL dose was the most effective, either alone or added to a food matrix, and also significantly decreased triglyceride content in nematodes fed on the CLA mixture. Furthermore, the antiobesity effect was related to the CLA isomer trans-10, cis-12. Finally, the transcriptional study showed C. elegans fed with Tonalin (1 μg/mL) underwent an upregulation of energy metabolism, reproduction, protein metabolism and oxidative stress processes. In conclusion, the results presented here clearly correlate well with other animal studies, demonstrating the value of C. elegans as a useful model to evaluate antiobesity compounds/ingredients.