A review of the effects of mushrooms on mood and neurocognitive health across the lifespan

Mushrooms contain bioactive compounds with documented antioxidant and anti-inflammatory actions. Here, we present a systematic evaluation of epidemiological and clinical studies that investigate the role of mushrooms, either as a separate or integral dietary component, on neurocognition and mood. Following a search of four databases, a total of 34 human studies examining the effect of different mushrooms across varying age cohorts and health statuses were selected for inclusion. Epidemiological studies included in this review (n = 24) revealed a significant benefit of dietary patterns that included mushrooms of any species on cognition and mood in both healthy and compromised populations. However, the results obtained from intervention studies (n = 10) were mixed. Studies mainly investigated Lion's Mane (Hericium erinaceus), showing some enhancement of mood and cognitive function in middle-aged and older adults. Further acute and chronic human intervention studies are needed, using adequate sample sizes, employing appropriately sensitive neurocognitive tests, and investigating a range of dietary mushrooms, to confirm the effects of mushroom supplementation on neurocognition and mood in humans.

Dietary phytochemical and metabolic disease prevention: Focus on plant proteins

Plant-based functional foods have attracted increasing research interest to validate their use in preventing metabolic disease. Since it is increasingly recognized that inflammation, oxidative stress, and circadian rhythm play vital roles in various metabolic diseases, including diabetes, obesity and non-alcoholic liver disease, plant proteins, protein hydrolysates, and food extracts that intervene in these biological processes are promising dietary supplements to prevent metabolic diseases. Here, we reviewed the recent research on plant-based foods used for metabolic disease prevention and provided new perspectives regarding the current study gaps and future directions in this field.

Oak extracts modulate circadian rhythms of clock gene expression in vitro and wheel-running activity in mice

Introduction

In mammals, the central circadian clock is located in the suprachiasmatic nucleus (SCN) of the hypothalamus, which coordinates the circadian rhythm and controls locomotor activity rhythms. In addition to SCN cells, the peripheral tissues and embryonic fibroblasts also have clock genes, such as Per1/2 and Bmal1, which generate the transcriptional-translational feedback loop to produce an approximately 24-h cycle. Aging adversely affects the circadian clock system and locomotor functions. Oak extract has been reported to improve age-related physiological changes. However, no study has examined the effect of oak extract on the circadian clock system.

Methods

We examined the effects of oak extract and its metabolites (urolithin A [ULT] and ellagic acid [EA]) on clock gene expression rhythms in mouse embryonic fibroblasts (MEFs) and SCN. Furthermore, locomotor activity rhythm was assessed in young and aged mice.

Results

Chronic treatment with EA and ULT delayed the phase of PER2::LUC rhythms in SCN explants, and ULT prolonged the period of PER2::LUC rhythms in MEFs in a dose-dependent manner and increased the amplitude of PER2::LUC rhythms in MEFs, though only at low concentrations. Acute treatment with ULT affected the phase of PER2::LUC rhythms in MEFs depending on the concentration and timing of the treatment. In addition, oak extract prolonged the activity time of behavioral rhythms in old mice and tended to increase daily wheel-running revolutions in both young and old mice.

Conclusions

These results suggest that oak extract is a novel modulator of the circadian clock in vitro and in vivo.

Supplementary Information

The online version contains supplementary material available at 10.1007/s41105-021-00365-2.

Erinacine A and related cyathane diterpenoids: Molecular diversity and mechanisms underlying their neuroprotection and anticancer activities

The presence of a fused 5/6/7 tricyclic core characterizes the group of cyathane diterpene natural products, that include more than 170 compounds, isolated from fungi such as Cyathus africanus and Hericium erinaceus. These compounds have a common biosynthetic precursor (cyatha-3,12-diene) and can be produced bio- or hemi-synthetically, or via total syntheses. Cyathane diterpenes display a range of pharmacological properties, including anti-inflammatory (possibly through binding to the iNOS protein) and neuroprotective effects. Many cyathanes like cyahookerin C, cyathin Q and cyafranines B and G can stimulate neurite outgrowth in cells, whereas conversely a few molecules (such as scabronine M) inhibit NGF-stimulated neurite outgrowth. The main anticancer cyathanes are erinacine A and cyathins Q and R, with a capacity to trigger cancer cell death dependent on the production of reactive oxygen species (ROS). These compounds, active both in vitro and in vivo, activate different signaling pathways in tumor cells to induce apoptosis (and autophagy) and to upregulate the expression of several proteins implicated in the organization and functioning of the actin cytoskeleton. An analysis of the functional analogy between erinacine A and other natural products known to interfere with the actin network in a ROS-dependent manner (notably cucurbitacin B) further supports the idea that erinacine A functions as a perturbator of the cytoskeleton organization. Collectively, we provide an overview of the molecular diversity of cyathane diterpenes and the main mechanisms of action of the lead compounds, with the objective to encourage further research with these fungal products. The anticancer potential of erinacine A deserves further attention but it will be necessary to better characterize the implicated targets and signaling pathways.

Docking Studies and Biological Evaluation of a Potential β-Secretase Inhibitor of 3-Hydroxyhericenone F from Hericium erinaceus

Alzheimer’s disease (AD) is the most common neurodegenerative disorder, affecting approximately more than 5% of the population worldwide over the age 65, annually. The incidence of AD is expected to be higher in the next 10 years. AD patients experience poor prognosis and as a consequence new drugs and therapeutic strategies are required in order to improve the clinical responses and outcomes of AD. The purpose of the present study was to screen a certain number of potential compounds from herbal sources and investigate their corresponding mode of action. In the present study, the learning and memory effects of ethanol:water (8:2) extracts from Hericium erinaceus were evaluated on a dementia rat model. The model was established by intraperitoneal injection of 100 mg/kg/d D-galactose in rats. The results indicated that the extracts can significantly ameliorate the learning and memory abilities. Specific active ingredients were screened in vivo assays and the results were combined with molecular docking studies. Potential receptor–ligand interactions on the BACE1-inhibitor namely, 3-Hydroxyhericenone F (3HF) were investigated. The isolation of a limited amount of 3HF from the fruit body of H. erinaceus by chemical separation was conducted, and the mode of action of this compound was verified in NaN₃-induced PC12 cells. The cell-based assays demonstrated that 3HF can significantly down-regulate the expression of BACE1 (p < 0.01), while additional AD intracellular markers namely, p-Tau and Aβ_1-42 were further down-regulated (p < 0.05). The data further indicate that 3HF can ameliorate certain mitochondrial dysfunction conditions by the reversal of the decreasing level of mitochondrial respiratory chain complexes, the calcium ion levels ([Ca²⁺]), the inhibiton in the production of ROS, the increase in the mitochondrial membrane potential and ATP levels, and the regulation of the expression levels of the genes encoding for the p21, COX I, COX II, PARP1, and NF-κB proteins. The observations suggest the use of H. erinaceus in traditional medicine for the treatment of various neurological diseases and render 3HF as a promising naturally occurring chemical constituent for the treatment of AD via the inhibition of the β-secretase enzyme.