Baicalein attenuates inflammatory responses by suppressing TLR4 mediated NF-κB and MAPK signaling pathways in LPS-induced mastitis in mice

Int Immunopharmacol. 2015 Sep;28(1):470-6. doi: 10.1016/j.intimp.2015.07.012. Epub 2015 Jul 18.

Abstract

Baicalein is a phenolic flavonoid presented in the dry roots of Scutellaria baicalensis Georgi. It has been reported that baicalein possesses a number of biological properties, such as antiviral, antioxidative, anti-inflammatory, antithrombotic, and anticancer properties. However, the effect of baicalein on mastitis has not yet been reported. This research aims to detect the effect of baicalein on lipopolysaccharide (LPS)-induced mastitis in mice and to investigate the molecular mechanisms. Baicalein was administered intraperitoneally 1h before and 12h after LPS treatment. The results indicated that baicalein treatment markedly attenuated the damage of the mammary gland induced by LPS, suppressed the activity of myeloperoxidase (MPO) and the levels of tumor necrosis factor (TNF-α) and interleukin (IL-1β) in mice with LPS-induced mastitis. Besides, baicalein blocked the expression of Toll-like receptor 4 (TLR4) and then suppressed the phosphorylation of nuclear transcription factor-kappaB (NF-κB) p65 and degradation inhibitor of NF-κBα (IκBα) and, and inhibited the phosphorylation of p38, extracellular signal-regulated kinase (ERK) and c-jun NH2-terminal kinase (JNK) in mitogen-activated protein kinase (MAPK) signal pathway. These findings suggested that baicalein may have a potential prospect against mastitis.

Keywords: Baicalein; Lipopolysaccharide; MAPKs; Mastitis; NF-κB; TLR4.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Anti-Inflammatory Agents / pharmacology*
  • Anti-Inflammatory Agents / therapeutic use*
  • Female
  • Flavanones / pharmacology*
  • Flavanones / therapeutic use*
  • Interleukin-1beta / metabolism
  • Lipopolysaccharides
  • MAP Kinase Signaling System / drug effects
  • Male
  • Mammary Glands, Animal / drug effects
  • Mammary Glands, Animal / pathology
  • Mastitis / chemically induced
  • Mastitis / drug therapy*
  • Mastitis / metabolism*
  • Mastitis / pathology
  • Mice, Inbred BALB C
  • Mitogen-Activated Protein Kinases / metabolism
  • NF-kappa B / metabolism
  • Peroxidase / metabolism
  • Signal Transduction / drug effects
  • Toll-Like Receptor 4 / metabolism
  • Tumor Necrosis Factor-alpha / metabolism

Substances

  • Anti-Inflammatory Agents
  • Flavanones
  • IL1B protein, mouse
  • Interleukin-1beta
  • Lipopolysaccharides
  • NF-kappa B
  • Tlr4 protein, mouse
  • Toll-Like Receptor 4
  • Tumor Necrosis Factor-alpha
  • baicalein
  • Peroxidase
  • Mitogen-Activated Protein Kinases