Soyasaponins reduce inflammation by downregulating MyD88 expression and suppressing the recruitments of TLR4 and MyD88 into lipid rafts.

ABSTRACT: BACKGROUND:Previous studies indicate that soyasaponins may reduce inflammation via modulating toll-like receptor 4 (TLR4)/myeloid differentiation factor 88 (MyD88) signaling. However, its underlying mechanisms are still not fully understood. METHODS:Lipopolysaccharide (LPS)-challenged inflamed male ICR mice were intervened by intragastrical administration with 10 and 20??mol/kg·BW of soyasaponin A1, A2 or I for 8?weeks. The serum inflammatory markers were determined by commercial kits and the expression of molecules in TLR4/MyD88 signaling pathway in liver by real-time PCR and western blotting. The recruitments of TLR4 and MyD88 into lipid rafts of live tissue lysates were detected by sucrose gradient ultracentrifugation and western blotting. LPS-stimulated RAW264.7 macrophages were treated with 10, 20 and 40??mol/L of soyasaponin A1, A2 or I for 2?h. MyD88-overexpressed HEK293T cells were treated with 20 and 40??mol/L of soyasaponins (A1, A2 or I) or 20??mol/L of ST2825 (a MyD88 inhibitor) for 6?h. The expression of molecules in TLR4/MyD88 signaling pathway were determined by western blotting. Data were analyzed by using one way analysis of variance or t-test by SPSS 20.0 statistical software. RESULTS:Soyasaponins A1, A2 or I significantly reduced the levels of tumor necrosis factor alpha (TNF?), interleukin (IL)-6 and nitric oxide (NO) in serum (p?

SUBMITTER: Chen J 

PROVIDER: S-EPMC7268359 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature