1. A Xanthohumol-Rich Hop Extract Diminishes Endotoxin-Induced Activation of TLR4 Signaling in Human Peripheral Blood Mononuclear Cells: A Study in Healthy Women
- Author
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Jung, Finn, Staltner, Raphaela, Baumann, Anja, Burger, Katharina, Halilbasic, Emina, Hellerbrand, Claus, and Bergheim, Ina
- Subjects
Lipopolysaccharides ,Flavonoids ,Propiophenones ,Plant Extracts ,Organic Chemistry ,Lipopolysaccharide Receptors ,Anti-Inflammatory Agents ,General Medicine ,Catalysis ,Computer Science Applications ,Inorganic Chemistry ,Toll-Like Receptor 4 ,Endotoxins ,HEK293 Cells ,Chalcones ,Leukocytes, Mononuclear ,CD14 ,LPS ,hop ,TLR4 ,inflammation ,Humans ,Cytokines ,Female ,ddc:610 ,Physical and Theoretical Chemistry ,Humulus ,Molecular Biology ,Spectroscopy - Abstract
Infections with Gram-negative bacteria are still among the leading causes of infection-related deaths. Several studies suggest that the chalcone xanthohumol (XN) found in hop (Humulus lupulus) possesses anti-inflammatory effects. In a single-blinded, placebo controlled randomized cross-over design study we assessed if the oral intake of a single low dose of 0.125 mg of a XN derived through a XN-rich hop extract (75% XN) affects lipopolysaccharide (LPS)-induced immune responses in peripheral blood mononuclear cells (PBMCs) ex vivo in normal weight healthy women (n = 9) (clinicaltrials.gov: NCT04847193) and determined associated molecular mechanisms. LPS-stimulation of PBMCs isolated from participants 1 h after the intake of the placebo for 2 h resulted in a significant induction of pro-inflammatory cytokine release which was significantly attenuated when participants had consumed XN. The XN-dependent attenuation of proinflammatory cytokine release was less pronounced 6 h after the LPS stimulation while the release of sCD14 was significantly reduced at this timepoint. The LPS-dependent activation of hTLR4 transfected HEK293 cells was significantly and dose-dependently suppressed by the XN-rich hop extract which was attenuated when cells were co-challenged with sCD14. Taken together, our results suggest even a one-time intake of low doses of XN consumed in a XN-rich hop extract can suppress LPS-dependent stimulation of PBMCs and that this is related to the interaction of the hop compound with the CD14/TLR4 signaling cascade.
- Published
- 2022