7-methoxyflavanone alleviates neuroinflammation in lipopolysaccharide-stimulated microglial cells by inhibiting TLR4/MyD88/MAPK signalling and activating the Nrf2/NQO-1 pathway. (22nd December 2019)

• Record Type: Journal Article
• Authors: Qu, Zhao; Chen, Yan; Luo, Zhuo-Hui; Shen, Xiao-Ling; Hu, Ying-Jie
• Is Part Of: Journal of pharmacy and pharmacology. Volume 72:Number 3(2020)
• Page Start: 385
• Page End: 395
• Publication Date: 2019-12-22
• Subjects: 7-methoxyflavanone -- lipopolysaccharide-induced microglia overactivation -- neuroinflammation -- Nrf2/NQO-1 signalling -- TLR4/MyD88/MAPK signalling; Pharmacy -- Periodicals; Pharmacology -- Periodicals; 615.1
• DOI: 10.1111/jphp.13219
• Languages: English
• ISSNs: 0022-3573

Abstract

Abstract: Objectives: Neuroprotective potential of 7-methoxyflavanone (7MF) and its underlying mechanism was investigated. Methods: Inhibitory effects of 7MF on microglial activation and neuroinflammation were evaluated by employment of lipopolysaccharide (LPS)-induced BV2 microglial cells. Changes in expression of genes and proteins of interest were investigated by RT-qPCR analysis and Western blot analysis. Inhibitory effects of 7MF on microglial overactivation were verified in LPS-treated C57BL/6J mice using ionized calcium-binding adaptor molecule-1 (Iba1) in the brain and interleukin-6 (IL-6) in serum as indicators. Key findings: In BV2 cells, pretreatment with 7MF antagonized LPS-induced production of inflammatory factors IL-6, tumour necrosis factor-α (TNF-α), cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), intercellular adhesion molecule-1 (ICAM-1) and monocyte chemoattractant protein-1 (MCP-1). Mechanistic studies revealed reduced expression of Toll-like receptor 4 (TLR4), myeloid differentiation factor-88 (MyD88), phosphorylated forms of c-Jun N-terminal kinase (p-JNK) and extracellular signal-regulated kinases 1/2 (p-ERK) but increased nuclear accumulation of nuclear factor erythroid 2-related factor 2 (Nrf2) and cellular expression of NAD(P)H quinone dehydrogenase-1 (NQO-1) by 7MF. In LPS-treated mice, pretreatment with 7MF reduced the brain level of Iba1 and serum level of IL-6. Conclusions: 7-methoxyflavanone inhibited LPS-stimulated TLR4/MyD88/MAPK signalling and activated Nrf2-mediated transcription of antioxidant protein NQO-1, showing antineuroinflammatory effect, so it is a potential neuroprotective agent.