**Crocetin Isolated from the Natural Food Colorant Sa**ff**ron Reduces Intracellular Fat in 3T3-L1 Adipocytes**

### **Elena Jiménez-Ortega 1, Aitana Braza-Boïls 2, Miguel Burgos 3, Natalia Moratalla-López 4, Manuel Vicente 5, Gonzalo L. Alonso 4, Eduardo Nava 5 and Sílvia Llorens 5,\***


**\*** Correspondence: silvia.llorens@uclm.es

Received: 7 October 2020; Accepted: 10 November 2020; Published: 12 November 2020

**Abstract:** Saffron, as a food colorant, has been displaced by low-cost synthetic dyes. These have unhealthy properties; thus, their replacement with natural food colorants is an emerging trend. Obesity is a worldwide health problem due to its associated comorbidities. Crocetin esters (crocins) are responsible for the red saffron color. Crocetin (CCT) exhibits healthful properties. We aimed to broaden the existing knowledge on the health properties of CCT isolated from saffron, to facilitate its consideration as a healthy natural food colorant in the future. We evaluated the ability of CCT (1 and 5 μM) to reduce lipid accumulation during the differentiation of 3T3-L1 preadipocytes. Intracellular fat was quantified by Oil Red O staining. CTT cytotoxicity was measured using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The number and size of lipid droplets were analyzed using WimLipid software. The expression of adipogenic genes (CCAAT/enhancer-binding protein (C/EBPβ, C/EBPδ, C/EBPα), and peroxisome proliferator-activated receptor γ (PPARγ)) was analyzed using quantitative real-time PCR (qRT-PCR). CCT 5 μM decreased intracellular fat by 22.6%, without affecting viability or lipid droplet generation, via a decrease in C/EBPα expression, implicated in lipid accumulation. Thus, CCT is a potential candidate to be included in dietary therapies aimed at reversing adipose tissue accumulation in obesity.

**Keywords:** saffron; crocetin; obesity
