The impact of some carotenoids has been documented in adipogenesis (
Figure 2), which could help obesity management via a limitation of lipid accumulation in adipocytes. Most of the reported effects inhibited adipocyte differentiation
[56][89] by interfering with nuclear receptors such as RAR, RXR or PPAR. β-Carotene inhibited adipogenesis through the production of β-apo-14′-carotenal and repression of PPARα, PPARγ and RXR activation
[57][90], but also through the production of all-trans retinoic acid
[18][34]. Similarly, β-cryptoxanthin suppressed adipogenesis via activation of RAR
[58][91], and astaxanthin inhibited rosiglitazone-induced adipocyte differentiation by antagonizing transcriptional activity of PPARγ
[59][92]. Zeaxanthin
[60][44] and fucoxanthin
[61][62][93,94] exhibited anti-adipogenic effects via a down-regulation of adipogenic transcription factors C/EBPα and PPARγ, which blunted lipid accumulation. Conversely, lycopene (unpublished personal data) and apo-10′-lycopenoic acid
[51][84] showed no effect on adipogenesis. Besides these effects, there is evidence that some effects of provitamin A carotenoids are mediated through retinol and its metabolite production, which are known to regulate adipogenesis
[45][50].