Effect of quercetin nanoemulsion on high-fat diet-induced adipose tissue inflammation in mice; 퀘르세틴 나노에멀젼의 고지방 식이 유도 마우스 지방조직 염증에 대한 효과

Abstract

Purpose: This study aimed to investigate the effects of quercetin nanoemulsion (QN) on white adipose tissue (WAT) inflammation in mice fed a high-fat diet (HFD). Methods: Male C57BL/6J mice were randomly divided into 4 groups (n = 6/group) and fed a normal chow diet, a 45 kcal% HFD, or an HFD supplemented with 0.025% QN (QN-L) or 0.05% QN (QN-H) for 11 weeks. Body weight, tissue weight, serum lipid and inflammatory marker levels, and gene expression levels in WAT were analyzed. Results: The QN-L and QN-H groups showed significantly reduced weight gain and WAT mass compared to the HFD group, despite no significant differences in food intake among the groups. Serum levels of triglycerides, total cholesterol, and low-density lipoprotein cholesterol were significantly lower in QN-supplemented groups compared to the HFD group. Serum levels of pro-inflammatory cytokines, including tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6), and chemokine (C-C motif) ligand 2 (CCL2) were significantly reduced in the QN-H group compared to the HFD group. There was a marked suppression of Tnf, Il6, and Ccl2 mRNA expression in the WAT QN-supplemented groups compared to the HFD group. Histological analysis of F4/80 immunostaining showed a marked reduction in crown-like structures, which are indicative of macrophage infiltration, in the QN-treated groups. The mRNA levels of inflammatory macrophage markers including adhesion G protein-coupled receptor E1, cluster of differentiation 68, and integrin alpha X were significantly downregulated, while the anti-inflammatory marker arginase 1 was upregulated in the QN-supplemented groups compared to the HFD group. Furthermore, nuclear factor kappa B (NF-κB) activity was significantly suppressed in the QN-H group compared to the HFD group. Conclusion: These results suggest that QN alleviates HFD-induced adipose tissue inflammation by modulating pro-inflammatory cytokines and macrophage polarization and inhibiting NF-κB activation. © 2025 Elsevier B.V., All rights reserved.