Antidepressant-like effect of Ganoderma lucidum spore polysaccharide-peptide mediated by upregulation of prefrontal cortex brain-derived neurotrophic factor

A scoping review of the effects of mushroom and fungus extracts in rodent models of depression and tests of antidepressant activity

One of the most important developments in psychopharmacology in the past decade has been the emergence of novel treatments for mood disorders, such as psilocybin for treatment-resistant depression. Psilocybin is most commonly found in different species of mushroom; however, the literature on mushroom and fungus extracts with potential antidepressant activity extends well beyond just psilocybin-containing mushrooms, and includes both psychedelic and non-psychedelic species. In the current review, we systematically review the preclinical literature on mushroom and fungus extracts, and their effects of animal models of depression and tests of antidepressant activity. The PICO structure, PRISMA checklist and the Cochrane Handbook for systematic reviews of intervention were used to guide the search strategy. A scoping search was conducted in electronic databases PubMed, CINAHL, Embase and Web of Science. The literature search identified 50 relevant and suitable published studies. These included 19 different species of mushrooms, as well as seven different species of other fungi. Nearly all studies reported antidepressant-like effects of treatment with extracts. Treatments were most commonly delivered orally, in both acute and chronically administered studies to predominantly male rodents. Multiple animal models of depression were used, the most common being unpredictable chronic mild stress, while the tail suspension test and forced swim test were most frequently used as standalone antidepressant screens. Details on each experiment with mushroom and fungus species are discussed in detail, while an evaluation is provided of the strengths and weaknesses of these studies.

Ganoderma lucidum spores-derived particulate β-glucan treatment improves antitumor response by regulating myeloid-derived suppressor cells in triple-negative breast cancer

Granular β-1,3-glucan extracted from the wall of Ganoderma lucidum spores, named GPG, is a bioregulator. In this study, we investigated the structural, thermal, and other physical properties of GPG. We determined whether GPG ameliorated immunosuppression caused by Gemcitabine (GEM) chemotherapy. Triple-negative breast cancer mice with GPG combined with GEM treatment had reduced tumor burdens. In addition, GEM treatment alone altered the tumor microenvironment(TME), including a reduction in antitumor T cells and a rise in myeloid-derived suppressor cells (MDSC) and regulatory T cells (Tregs). However, combined GPG treatment reversed the tumor immunosuppressive microenvironment induced by GEM. GPG inhibited bone marrow (BM)-derived MDSC differentiation and reversed MDSC expansion induced by conditioned medium (CM) in GEM-treated E0771 cells through a Dectin-1 pathway. In addition, GPG downgraded PD-L1 and IDO1 expression on MDSC while boosting MHC-II, CD86, TNF-α, and IL-6 expression. In conclusion, this study demonstrated that GPG could alleviate the adverse effects induced by GEM chemotherapy by regulating TME.

A review of the pharmacological action and mechanism of natural plant polysaccharides in depression

Depression is a prevalent mental disorder. However, clinical treatment options primarily based on chemical drugs have demonstrated varying degrees of adverse reactions and drug resistance, including somnolence, nausea, and cognitive impairment. Therefore, the development of novel antidepressant medications that effectively reduce suffering and side effects has become a prominent area of research. Polysaccharides are bioactive compounds extracted from natural plants that possess diverse pharmacological activities and medicinal values. It has been discovered that polysaccharides can effectively mitigate depression symptoms. This paper provides an overview of the pharmacological action and mechanisms, intervention approaches, and experimental models regarding the antidepressant effects of polysaccharides derived from various natural sources. Additionally, we summarize the roles and potential mechanisms through which these polysaccharides prevent depression by regulating neurotransmitters, HPA axis, neurotrophic factors, neuroinflammation, oxidative stress, tryptophan metabolism, and gut microbiota. Natural plant polysaccharides hold promise as adjunctive antidepressants for prevention, reduction, and treatment of depression by exerting their therapeutic effects through multiple pathways and targets. Therefore, this review aims to provide scientific evidence for developing polysaccharide resources as effective antidepressant drugs.

The molecular mechanism of polysaccharides in combating major depressive disorder: A comprehensive review

Major depressive disorder (MDD) is a complex psychiatric condition with diverse etiological factors. Typical pathological features include decreased cerebral cortex, subcortical structures, and grey matter volumes, as well as monoamine transmitter dysregulation. Although medications exist to treat MDD, unmet needs persist due to limited efficacy, induced side effects, and relapse upon drug withdrawal. Polysaccharides offer promising new therapies for MDD, demonstrating antidepressant effects with minimal side effects and multiple targets. These include neurotransmitter, neurotrophin, neuroinflammation, hypothalamic-pituitary-adrenal axis, mitochondrial function, oxidative stress, and intestinal flora regulation. This review explores the latest advancements in understanding the pharmacological actions and mechanisms of polysaccharides in treating major depression. We discuss the impact of polysaccharides' diverse structures and properties on their pharmacological actions, aiming to inspire new research directions and facilitate the discovery of novel anti-depressive drugs.

A Neutral Polysaccharide from Spores of Ophiocordyceps gracilis Regulates Oxidative Stress via NRF2/FNIP1 Pathway

Ophiocordyceps gracilis (O. gracilis) is a parasitic fungus used in traditional Chinese medicine and functional foods. In this study, a neutral heteropolysaccharide (GSP-1a) was isolated from spores of O. gracilis, and its structure and antioxidant capacities were investigated. GSP-1a was found to have a molecular weight of 72.8 kDa and primarily consisted of mannose (42.28%), galactose (35.7%), and glucose (22.02%). The backbone of GSP-1a was composed of various sugar residues, including →6)-α-D-Manp-(1→, →2,6)-α-D-Manp-(1→, →2,4,6)-α-D-Manp-(1→, →6)-α-D-Glcp-(1→, and →3,6)-α-D-Glcp-(1→, with some branches consisting of →6)-α-D-Manp-(1→ and α-D-Gal-(1→. In vitro, antioxidant activity assays demonstrated that GSP-1a exhibited scavenging effects on hydroxyl radical (•OH), 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid radical cation (ABTS•+), and 2,2-diphenyl-1-picrylhydrazyl radical (DPPH•). Moreover, GSP-1a was found to alleviate H2O2-induced oxidative stress in HepG2 cells by reducing the levels of reactive oxygen species (ROS) and malondialdehyde (MDA), while enhancing the activities of superoxide dismutase (SOD). Furthermore, GSP-1a upregulated the mRNA expression of antioxidant enzymes such as Ho-1, Gclm, and Nqo1, and regulated the NRF2/KEAP1 and FNIP1/FEM1B pathways. The findings elucidated the structural types of GSP-1a and provided a reliable theoretical basis for its usage as a natural antioxidant in functional foods or medicine.

Antioxidant activity and cytotoxicity of exopolysaccharide from mushroom Hericium coralloides in submerged fermentation

Mushrooms of the genus Hericium spp. represent a series of delicious edible mushrooms with medicinal value. Here, for the first time, the species native to Iran, the mushroom Hericium coralloides, was collected in Mazandaran province, identified, and registered with the NCBI under accession number MW136052. The production of exopolysaccharides (EPS) in submerged culture was optimized using the response surface method. Among the physicochemical and culture medium conditions tested, rotation speed and concentration of maltose and peptone of soybean significantly affected the production of EPS. The proposed model predicts maximum EPS production (0.13 g/L) at 50 g/L maltose, 3 g/L soy peptone, and 1 g/L yeast extract, pH = 6.5, 200 rpm, inoculum at 5% v/v, and 22 °C. The molecular weight of the EPS chains was 413 and 1578 Da. EPS has antioxidant action (EC50 = 6.59 mg/mL) and cytotoxic activity against cancer cells. The viability of AGS and MKN-45 cancer cell lines declined to 20 and 30% after 48 h of the EPS treatment. H. coralloides EPS could be considered a natural dietary anti-cancer supplement. Further studies are necessary to understand the mechanism of the H. coralloides EPS activity on the cell cycle of cancer cells and to prove its action in vivo.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13399-022-03386-0.

Edible Mushrooms as a Potential Component of Dietary Interventions for Major Depressive Disorder

Dietary interventions for people suffering from major depressive disorder (MDD) are an ongoing field of research. In this article, we present a comprehensive background for understanding the possibility of using edible medicinal mushrooms as an adjunctive treatment for MDD. We start with a brief history of MDD, its diagnosis, epidemiology and treatment, and the effects of diet on depression symptoms, followed by a review of neurobiological, behavioral, and clinical studies of medicinal mushrooms. We specifically highlight the results of preclinical and clinical studies on dietary supplementation with three selected mushroom species: Lion’s mane (Hericium erinaceus), Caterpillar mushroom (Cordyceps militaris), and Lingzhi/Reishi (Ganoderma lucidum). Preliminary small-sample clinical studies suggest that Lion’s mane can influence well-being of humans. In the case of Reishi, the results of clinical studies are equivocal, while in the case of Caterpillar Mushroom, such studies are underway. Edible mushrooms contain 5-hydroxy-L-tryptophan (5-HTP), which is a direct precursor of serotonin—a neurotransmitter targeted in pharmacotherapy of MDD. Therefore, in light of the well-recognized role of stress as a pathogenic factor of MDD, we also describe the neurobiological mechanisms of the interaction between stress and serotonergic neurotransmission; and summarize the current state of knowledge on dietary supplementation with 5-HTP in MDD.