Abstract
Background: Exaggerated Toll-like receptor (TLR)-mediated immune and inflammatory responses play a role in inflammatory bowel diseases. This report deals with the ability of a mixture of oxysterols widely present in cholesterol-rich foods to induce in vitro intestinal inflammation through TLR up-regulation. The anti-inflammatory action of four cocoa bean shell (CBS) extracts with different polyphenol content, was tested. Methods: Differentiated intestinal CaCo-2 cells were treated with a dietary oxysterol mixture (Oxy-mix) (60 µM). The expression and activation of TLR2 and TLR4, as well as the production of their downstream signaling effectors IL-8, IFNβ and TNFα were analyzed in the presence or absence of TLR antibodies. Honduras CBS extracts were characterized for their polyphenol contents; their anti-inflammatory action was analyzed in CaCo-2 cells treated with Oxy-mix. Results: Oxysterol-dependent TLR-2 and TLR4 over-expression and activation together with cytokine induction were abolished by blocking TLRs with specific antibodies. Polyphenol-rich CBS extracts consisting of high quantities of (−)-epicatechin and tannins also prevented TLR induction. Conclusions: TLR2 and TLR4 mainly contribute to inducing oxysterol-dependent intestinal inflammation. The fractionation method of CBS allowed the recovery of fractions rich in (−)-epicatechin and tannins able to counteract oxysterol-induced inflammation, thus highlighting the beneficial biological potential of specific CBS extracts.
Highlights
Toll-like receptors (TLRs) are the main pattern recognition receptors, which mediate innate immunity and inflammatory responses against pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs)
Differentiated CaCo-2 cells were treated with 60 μM oxysterol mixture (Oxy-mix) in order to provide evidence of the potential ability of oxysterol to increase TLR2 and/or TLR4 expression
A time-dependent induction of TLR mRNA was detected by incubating cells with the Oxy-mix for
Summary
Toll-like receptors (TLRs) are the main pattern recognition receptors, which mediate innate immunity and inflammatory responses against pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs). The altered activation of these receptors plays a role in the pathogenesis of inflammatory intestinal diseases such as inflammatory bowel diseases (IBDs) [1]. Exaggerated Toll-like receptor (TLR)-mediated immune and inflammatory responses play a role in inflammatory bowel diseases. Honduras CBS extracts were characterized for their polyphenol contents; their anti-inflammatory action was analyzed in CaCo-2 cells treated with Oxy-mix. Polyphenol-rich CBS extracts consisting of high quantities of (−)-epicatechin and tannins prevented TLR induction. The fractionation method of CBS allowed the recovery of fractions rich in (−)-epicatechin and tannins able to counteract oxysterol-induced inflammation, highlighting the beneficial biological potential of specific
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
