Suppressive effect of glycyrrhizic acid against lipopolysaccharideinduced neuroinflammation and cognitive impairment in C57 mice via toll-like receptor 4 signaling pathway

  • Wenfeng Liu
  • Shun Huang
  • Yonglian Li
  • Kun Zhang
  • Xi Zheng
Keywords: glycyrrhizinic acid; LPS; neuroinflammation; memory impairments; Toll-like receptor (TLR4)


Background: Glycyrrhizinic acid (GA), a major active ingredient enriched in the roots of licorice, possesses well-confirmed anti-inflammatory effects.

Objective: To evaluate the underlying mechanisms of GA against lipopolysaccharide (LPS)-induced chronic neuroinflammation and memory impairment.

Design: We explored to investigate the effects of GA on neuroinflammation and memory impairment in an LPS-induced Alzheimer’s mouse model.

Results: Data of micro-PET/CT imaging and morris water maze test suggested that GA, when administrated orally, could reverse LPS-induced abnormalized glucose intake and metabolism in the brain and alleviate LPS-induced memory loss and cognitive defects in mice. Histological and immunohistochemical staining results revealed that GA treatment suppressed overexpressions of pro-inflammatory cytokines of IL-1 β and TNF-α in the brain of C57 mice by inhibiting toll-like receptor 4 (TLR4) signaling pathway activation.

Conclusion: Our findings suggest that GA may be a therapeutic agent for the treatment of neuroinflammation and cognitive impairment.


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How to Cite
Liu W, Huang S, Li Y, Zhang K, Zheng X. Suppressive effect of glycyrrhizic acid against lipopolysaccharideinduced neuroinflammation and cognitive impairment in C57 mice via toll-like receptor 4 signaling pathway. fnr [Internet]. 2019Apr.29 [cited 2019May19];630. Available from:
Original Articles