Aaby, Kjersti

Bergum, Silje

Borge, Grethe Iren Andersen

Rønning, Sissel Beate

Voldvik, Vibeke

NOFIMA Repository

Nofima AS, P. O. Box 210, Osloveien 1, NO-1431 Ås, Norway, Tel: +47 02140, www.nofima.no, post@nofima.no - Norwegian Institute of Food, Fisheries and Aquaculture ResearchNBS’ contact meeting, 19th – 22nd of January 2017, Storefjell, NorwayPolyphenol metabolites display immune inhibiting effects onacute inflammation in human monocyte and macrophage cellsSissel B. Rønning, Vibeke Voldvik, Silje Bergum, Kjersti Aaby, Grethe Iren Andersen Borge Nofima AS, The Norwegian Institute of Food, Fisheries and Aquaculture Research, Ås, NorwayBackground: The dietary polyphenols ellagitannins, present in strawberry, raspberry and pomegranate, are catabolized toellagic acid and further to urolithins by the colonic microbiota. Urolithin A is one of the main metabolites found in plasma.Ellagic acid is only found in minor amounts. Many studies support the positive effect on the immune system of polyphenols;however, usually the effects are of polyphenols only found in foods, and not of the metabolites present in circulation.Results 1. Ellagic acid and urolithin A decreased NF-κB activity during acute inflammationAim: To examine and compare immune inhibitingeffects on acute inflammation of ellagic acid and itscatabolite urolithin A, which are both present in thecirculation after consumption of certain fruits andberries.Conclusion:Both ellagic acid and urolithin A displayed immuneinhibiting effects on acute inflammation, however,urolithin A had a stronger effect than ellagic acid. Thereason for this might be different regulation of NF-κB.Figure 1: Ellagitannins are converted to ellagic acid which is converted to among others urolithin A during digestion. Both urolithin A and ellagic acid are present in the blood and affect the immune system. Figure 2: Bars show NF-κB activity relative to control w/ LPS only during acute inflammation in U937cells. Asterisk denote significant differences between metabolites compared with cells incubatedwith LPS only. Bars presented are mean of minimum three independent experiments ±SEM.2. Urolithin A reduced the mRNA expression and cytokine secretion of both IL-6 and TNF-α, while ellagic acid only reduced the TNF-α cytokine secretion. ***020406080100120control w/o LPS control w/ LPS ellagic acid 30 µM urolithin A 30 µM% of control w/ LPSNF-κB activityFigure 4: Bars show the relative gene expression of the immunereceptor TLR-4 during acuteinflammation in U937 cells. No significant differences between metabolites compared with cellsincubated LPS only were found. Bars presented are mean of minimum three independent experiments ±SEM.Figure 3a) Bars show the relative gene expression of IL-6 and TNF-α in U937 cells during acute inflammation. b) Bars show cytokinesecretion level of IL-6 and TNF-α relative to control w/ LPS only during acute inflammation in THP-1 cells. Asterisk denote significantdifferences between metabolites compared with cells incubated with LPS only. Bars presented are mean of minimum threeindependent experiments ±SEM.00,20,40,60,811,21,41,6control w/o LPS control w/ LPS ellagic acid 30 µM urolithin A 30µMFold changemRNA expression3. Ellagic acid and urolithin A did not affect the relative gene expression of the immune receptor TLR-44. Urolithin A reduced the nuclear localisation of phosphorylated NF-κB units p65 andp50, while ellagic acid only reduced the nuclear localisation of p65****-0,200,20,40,60,811,21,41,6IL-6 TNF-αFold changemRNA expressionMethodsUrolithin A, that was kindly provided by partners in the EU-project ‘BACCHUS’ (FP7, no. 312090), and ellagic acid were examined for their effects on acute inflammation responses caused by the bacterialendotoxin LPS in human monocyte and macrophage cells. U937 3xκB-LUC cells and differentiated THP-1 cells were stimulated with 30 µM metabolites for 6 or up to 24 hours during acute inflammationinduced by LPS. To measure the immune inhibiting effects, U937 was used to measure NF-κB activity with luminescence, and mRNA expression of the pro-inflammatory cytokines IL-6 and TNF-α, and theimmune receptor TLR-4 using RT-PCR. In addition, THP-1 cells were measured for secretion of the pro-inflammatory cytokines IL-6 and TNF-α using sandwich ELISA, and for nuclear localisation of p50 and p65using immunostaining. Dunnett’s Multiple Comparisons with a control was performed using the Minitab 17 software for calculation of significant difference between samples.Figure 5: Immunostaining of the phosphorylated NF-κB subunits p65 and p50 during actue inflammation in THP-1 cellsdemonstrate a nuclear localisation in control cells, and a reduced expression in cells treated with urolithin A. No reduction in nuclear localisation or expression of p50 was observed when treated with ellagic acid.* *** *-20020406080100120IL-6 TNF-α% ofcontrolw/LPScytokine secretioncontrol w/o LPScontrol w/ LPSellagic acid 30 µMurolithin A 30 µMa bPlease contact  vibeke.voldvik@nofima.nofor more informationAcknowledgmentsThe research leading to these results has received funding from the European Union Seventh Framework Programme (FP7/2007-2013) under grant agreement no 312090, and Norwegian Levy on Agricultural Products under grant agreement no 224892.

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Polyphenol metabolites display immune inhibiting effects on acute inflammation in human monocyte and macrophage cells

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NORA - Norwegian Open Research Archives

https://nofima.brage.unit.no/nofima-xmlui/bitstream/11250/2431280/2/Poster%2bBacchus%2bNBS%2527%2bvinterm%25C3%25B8te2017.pdf

Polyphenol metabolites display immune inhibiting effects on acute inflammation in human monocyte and macrophage cells

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