Effects of propolis flavonoids on activation of NLRP3 inflammasome in monocytes

ZHANG Xiao-hui; ZENG Wei; CHEN Peng; YAO Shu-tong

doi:10.3969/j.issn.1002-266X.2015.39.004

Abstract：Objective To explore the effects of propolis flavonoids on the activation of oxidized low-density lipoprotein (ox-LDL) induced nucleotide-binding oligomerization domain-like receptor containing protein 3 (NLRP3) inflammasome in mononuclear cells .Methods The monocytes THP1 were cultured and divided into five groups .The experimental groups 1, 2, 3 and the model group were treated with 100 μg/mL ox-LDL to produce mononuclear inflammatory reaction models . The monocytes of the experimental groups 1, 2 and 3 were treated with 5, 10 and 15μg/mL propolis flavonoids before ox-LDL, and the monocytes of the control group was treated by ox-LDL in the absence of propo1is flavonoids.After 24 h, the expression of NLRP3 was measured by Western blotting .The levels of IL-1βand IL-18 were measured by ELISA .Results The levels of NLRP3 protein in the control group , model group and the experimental groups 1, 2 and 3 were 0.26 ± 0.04, 1.12 ±0.15, 0.98 ±0.11, 0.65 ±0.07 and 0.52 ±0.06, respectively.The expression of NLRP3 protein was sig-nificantly increased in the model group as compared with that in the control group (all P<0.05).The expression of NL-RP3 protein in the experimental groups 2 and 3 was significantly decreased as compared with that of the model group ( all P<0.05).The levels of IL-1βand IL-18 was significantly higher in the model group as compared with those of the control group, and the levels of IL-1βand IL-18 in the experimental groups 2 and 3 was significantly decreased as compared with those of the model group (all P<0.05).Conclusion Propolis flavonoids may down-regulate the expression of NLRP3 protein in the ox-LDL induced inflammatory response of the mononuclear cells , decrease the levels of IL-1βand IL-18 and inhibit the activation of NLRP 3 inflammasome .