Curcumin attenuates inflammatory responses by suppressing TLR4-mediated NF-κB signaling pathway in lipopolysaccharide-induced mastitis in mice

Curcumin, the main constituent of the spice turmeric, has been reported to have potent anti-inflammatory properties. However, the effect of curcumin on lipopolysaccharide (LPS)-induced mice mastitis has not been investigated. The aim of this study was to investigate whether curcumin could ameliorate the inflammation response in LPS-induced mice mastitis and to clarify the possible mechanism. The mouse model of mastitis was induced by injection of LPS through the duct of the mammary gland. Curcumin was applied 1 h before and 12 h after LPS treatment. The results showed that curcumin attenuated the infiltration of inflammatory cells, the activity of myeloperoxidase (MPO), and the expression of tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6) and interleukin-1 beta (IL-1 beta) in a dose-dependent manner. Additionally, Western blotting results showed that curcumin inhibited the phosphorylation of I kappa B-alpha. and NF-kappa B p65 and the expression of TLR4. These results indicated that curcumin has protective effect on mice mastitis and the anti-inflammatory mechanism of curcumin on LPS-induced mastitis in mice may be due to its ability to inhibit TLR4-mediated NF-kappa B signaling pathways. Curcumin may be a potential therapeutic agent against mastitis. 2014 Elsevier B.V. All rights reserved.