Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China.
Inflammation. 2018 Mar;41(2):437-448. doi: 10.1007/s10753-017-0700-8.
Rosmarinic acid (RA), a type of food additives mainly extracted from rosemary, has been reported to possess anti-inflammatory activities in some previous studies. However, the effects of RA on lipopolysaccharide (LPS)-induced mastitis have not been reported. Here, we investigated the anti-inflammatory effects of RA on LPS-induced mastitis in mice and elucidated the potential mechanisms in mouse mammary epithelial cells (mMECs). RA treatment significantly ameliorated the mammary structural damage, and reduced the activity of myeloperoxidase. ELISA and qPCR results indicated that RA dose-dependently decreased the expression of TNF-α, IL-1β, and IL-6 both in tissues and mMECs. Furthermore, RA remarkably suppressed the protein levels of TLR4, MyD88, IRAK1, TRAF6, and p-IKKβ. In addition, RA was also found to inhibit LPS-induced NF-κB signaling pathway activation. These results suggest that RA effectively attenuates LPS-induced mastitis by inhibiting the TLR4/MyD88/NF-κB signaling pathway.
迷迭香酸（RA）是一种主要从迷迭香中提取的食品添加剂，已有研究报道其具有抗炎活性。然而，RA 对脂多糖（LPS）诱导的乳腺炎的影响尚未见报道。在这里，我们研究了 RA 对 LPS 诱导的乳腺炎的抗炎作用，并在小鼠乳腺上皮细胞（mMEC）中阐明了潜在的机制。RA 处理显著改善了乳腺结构损伤，降低了髓过氧化物酶的活性。ELISA 和 qPCR 结果表明，RA 呈剂量依赖性地降低了组织和 mMEC 中 TNF-α、IL-1β 和 IL-6 的表达。此外，RA 还显著抑制了 TLR4、MyD88、IRAK1、TRAF6 和 p-IKKβ 的蛋白水平。此外，还发现 RA 抑制 LPS 诱导的 NF-κB 信号通路的激活。这些结果表明，RA 通过抑制 TLR4/MyD88/NF-κB 信号通路有效减轻 LPS 诱导的乳腺炎。
