Health gut microbiota mediated effects of mushrooms: potential in neuroprotection

Gut microbiota dysbiosis has been directly connected with several clinical conditions, including neurodegenerative disorders[1-4]. Many neuroactive molecules produced by intestinal flora such as short-chain fatty acids (SCFAs), gamma-aminobutyric acid (GABA), and serotonin, have been shown to contribute to healthy brain function[2,3]. Alzheimer’s disease (AD) has been connected with these metabolite reductions[1,3,4]. The intestinal microbiota dysregulation and aging have been associated with increased permeability of the gastrointestinal tract epithelium and blood-brain barrier. This result in transport mechanisms alteration[3,4]. Gut microbiota modulation has been suggested as a potential tool for AD and diet is believed to be a powerful driver in this modulation[2-4]. Numerous studies showed the prebiotic potential of mushrooms or mushroom polysaccharide extracts. β-glucans and other mushroom prebiotic molecules strongly stimulate the production of neuroactive metabolites by gut microbiota[4]. In this work, we aimed to assess the state-of-the-art of mushroom prebiotic potential and their gut microbiota-mediated effects. In our literature review, we reobserved that most research in the field studied the prebiotic capacity through in vitro human fecal fermentation experiments, a key approach to assessing the impact on gut bacteria and SCFA production. Typically, the data suggested an ability to modulate human intestinal microbiota and SCFA increase. Specific gut microbiota-mediated effects are also reported, mainly through animal studies. Some recent studies showed the potential of some mushroom species (e.g. Agaricus spp. and Sparassis crispa) in neurotransmitter level modulation and/or brain oxidative stress markers reduction, probably through the gut-brain axis. However, more research is needed to fully understand the underlying mechanisms.