Session Chair:
Carsten Zufall (Head of Technology and Innovation, Cervecería Polar, VE)
Synergistic protective effects of iso-alpha-acids and xanthohumol against pathological mechanisms of liver injury
By Claus Hellerbrand and Ina Bergheim, Universität Erlangen
Iso-alpha-acids (IAA) and xanthohumol (XN) are hop derived compounds in beer. We previously demonstrated beneficial effects of IAA and XN in different models of liver disease and showed that beer causes less liver injury than pure alcohol. However, the concentrations of IAA and XN in beer are too low to fully explain the beneficial effects of moderate beer doses leading to the hypothesis that their combination may be more potent. Within the Joint ERAB EBC project grant 2018 we analyzed the combined effect IAA and xanthohumol in cell culture experiments with human liver cells called hepatic stellate cells (HSC), which play a critical role in hepatic inflammation and fibrosis, i.e. the scaring of the liver in response to injury. Low doses of IAA and XN alone showed no effects, however, the combination of the same low dosese significantly inhibited the proliferation and production of pro-inflammatory and pro-fibrogenic proteins in HSC from 12 different human donors. These data indicate a synergistic inhibitory effect IAA and XN on critical pathological mechanisms of liver injury, and thus, could be an explanation for beneficial health effect of moderate beer consumption.
Effect of xanthohumol on lipoteichoic acid-induced immune response in human peripheral mononuclear blood cells
By Ina Bergheim et al., Universität Vienna
Results of studies in rodents and in-vitro studies suggest that xanthohumol (XN), a polyphenol derived from hops, exhibits anti-inflammatory properties. Studies assessing the effect of XN in humans are limited. The aim of this placebo-controlled crossover study was to determine the effect of low doses of XN on peripheral blood mononuclear cells in humans. Subjects either randomly received orally XN or a placebo together with a standardized breakfast in a cross-over design. Before and after ingestion blood was drawn and peripheral mononuclear blood cells (PBMCs) were isolated and then stimulated with lipoteichoic acid (LTA), a bacterial toxin derived from gram positive bacteria. In the placebo group, stimulation of PBMCs with the bacterial toxin resulted in a significant increase in cytokine release. In contrast, in cells isolated after the ingestion of XN, LTA-dependent cytokine release was significantly attenuated. Taken together our data so far suggest that the intake of low doses of XN can module the LTA-induced immune response of blood cells. Acknowledgement: This project is funded within the Joint ERAB EBC project grant 2018.
Specific hop compounds inhibit the SARS-CoV-2 replication in human cells
By Sascha Venturelli et al., Universität Hohenheim
The current events in connection with the Covid 19 pandemic have made it evident that, in addition to direct vaccination protection, the targeted prevention of infectious diseases should be given a particularly high priority. Therefore, there is a search for lead structures that prevent the infection or the replication cycle of the SARS-CoV-2 virus in humans and thus impede the spread of the virus. In the investigation of natural substances, two natural constituents of hops could be identified (HI-I and HI-II), which can even be found in beer in small quantities. They minimise the replication of the SARS-CoV-2 virus in human Caco-2 cells and, for HI-I in higher concentrations, even completely prevent it. Molecular analyses were able to show an interaction of the SARS-CoV-2 virus Papain-Like Protease (PLpro) with these two hop active substances both in the computer model and in experiments with the purified enzymes. These interesting results currently serve as a basis for further investigation into the extent to which the hop constituents are suitable for the treatment of SARS-CoV-2 virus infections, either directly or as a lead structure for target specific therapeutics.