Korean J Obes 2014; 23(3): 170-178
Published online September 30, 2014
Copyright © Korean Society for the Study of Obesity.
Chu-Sook Kim*, Rina Yu
Department of Food Science and Nutrition, University of Ulsan, Ulsan, Korea
This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
Background: Obesity-induced adipose inflammation contributes to the development of metabolic disorders such as insulin resistance and type 2 diabetes. In this study, we investigated whether quercetin, a naturally occurring phytochemical, can attenuate adipose tissue inflammation in obese mice.
Methods: Male C57BL/6 mice were randomly assigned into either control (RD, N=6), high fat diet (HFD, N=6), or HFD supplemented with 0.05% quercetin (HFD+Que, N=6) groups and treated with their respective diets for 9 weeks. The inflammatory cytokine proteins were measured by ELISA, and macrophage populations were determined by immunohistochemistry. The inflammatory receptors and downstream signaling molecules were measured by qPCR and western blot, respectively.
Results: We show here that in an HFD-fed mice model, quercetin supplementation reduced adipose tissue weight without affecting HFD-induced body weight gain. Quercetin supplementation reduced expression of inflammatory cytokines (TNF-α, MCP-1, MIP-1α) and macrophage accumulation (F4/80) in adipose tissue of an HFD-fed mice. Quercetin also suppressed the expression of inflammatory receptors (CCR2, TLR4, TNFRSF9) and the activation of downstream inflammatory signaling molecules (JNK, NF-κB) in adipose tissue.
Conclusion: These findings indicate that quercetin can reduce adipose inflammatory responses in mice exposed to HFD by inhibiting inflammatory cytokines production, inflammatory receptor expression and their signaling pathway. Quercetin may be useful for preventing HFD-induced adipose tissue inflammation.
Keywords: Quercetin, Inflammatory receptor, Adipose tissue, Inflammation, Obesity