Lycopene suppresses LPS-induced NO and IL-6 production by inhibiting the activation of ERK, p38MAPK, and NF-κB in macrophages
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Lycopene has antioxidant, anticancer, and anti-inflammatory effects with molecular mechanisms not fully identified.
Aim and methods
We investigated the effects of lycopene on the inflammatory responses to lipopolysaccharide (LPS) in RAW264.7 cells and the signal transduction pathways involved.
Lycopene inhibited LPS-induced production of nitric oxide (NO) and interleukin-6 (IL-6) with decreased mRNAs of inducible nitric oxide synthase and IL-6 but had no effect on TNF-α. Further study showed that lycopene also inhibited LPS-induced IκB phosphorylation, IκB degradation, and NF-κB translocation. Moreover, lycopene blocked the phosphorylation of ERK1/2 and p38 MAP kinase but not c-Jun NH2-terminal kinase. To confirm the causal link between MAP kinase inhibition and its anti-inflammatory effects, we treated the cells with SB 203580 and U0126. These inhibitors significantly inhibited LPS-induced NO and IL-6 formation.
Lycopene inhibits the inflammatory response of RAW 264.7 cells to LPS through inhibiting ERK/p38 MAP kinase and the NF-κB pathway.
KeywordsLycopene Interleukin-6 Nitric oxide p38 MAP kinase ERK1/2
This work was supported by research grants from the National Basic Research Program (973, No. 2006CB503902), China, the eleventh “five year” national research program of China (2008BAI58B06, 2009–2010), and by a research grant from the Swedish Nutrition Foundation and Lund University Hospital, Lund, Sweden.
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