Iso-α-acids in Nonalcoholic and Alcoholic Beer Stimulate Growth of Neuron-like SH-SY5Y Cells and Neuroepithelial Stem Cells.

With the increasing popularity of nonalcoholic beer, the association between beer drinking and alcohol intake is lost. In the present study, we show that nonalcoholic beer can stimulate the expansion of neuron-like cell lines and neuroepithelial stem cells in culture, yielding an effect comparable to that of alcoholic beer. One ingredient in beer is hops, which is derived from the flower of hop plants. The female flower contains humulones, which are transformed into iso-α-acids during wort boiling and give beer its bitter taste. In this study, we tested the effects of these iso-α-acids and/or alcohol on the proliferation of neuron-like cells and neuroepithelial stem cells in culture. Iso-α-acids enhanced cell expansion, showing a bimodal dose-response curve with peaks around 2-30 nM and 2-5 µM, of which nanomolar concentrations are relevant in beer drinking. The more lipophilic trans-iso-α-acids, found to a greater extent in beer foam, are even more potent. Our results indicate that iso-α-acids, acting via peroxisome proliferator-activated receptors could be responsible for the observed effects. Altogether, our results indicate that nonalcoholic beer with ingredients such as iso-α-acids stimulate the proliferation of neuroepithelial stem cells.