Shingled Hedgehog

Metadata

Regulatory Status

European Union

• Food use: S. imbricatus is a traditional wild-harvested edible mushroom in northern and central Europe, particularly Scandinavia. Widely consumed fresh and dried. In Nordic countries (Norway, Sweden, Finland), it has been part of traditional foraging culture for centuries.
• Novel food: The whole fruiting body has a history of consumption. Concentrated extracts or isolated compounds would likely require novel food authorization.
• Conservation concern: In some European regions, the species has declined due to nitrogen deposition and habitat loss. Listed as endangered or near-threatened in some national Red Lists.

United States

• Food use: Consumed as a wild edible in North America, though less commonly than in Europe.
• Dietary supplement: Not marketed as a dietary supplement. Not established as a supplement ingredient.

China and Japan

• China: S. imbricatus and related species (S. aspratus, S. scabrosus) are consumed as food and studied for medicinal properties. Not listed in the Chinese Pharmacopoeia.
• Japan: S. aspratus (kurokawa) is consumed in Japan. S. imbricatus itself is not a significant commercial species in Japan.
• Korea: Known and consumed as a wild edible.

Conditions & Indications

Primary: Antioxidant and Anti-fatigue Effects (Preclinical Evidence)

• Antioxidant capacity: Administration of powdered S. imbricatus fruiting bodies to mice suppressed levels of malondialdehyde (MDA) and reactive oxygen species (ROS), while increasing levels of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), demonstrating significant antioxidant capacity in vivo.
• Anti-fatigue: S. imbricatus extract exhibited antifatigue activity in both acute exercise-treated and chronic fatigue syndrome mouse models via regulation of the Nrf2-mediated oxidative stress pathway.

Secondary: Antiviral Activity (Preclinical Evidence)

• Coronavirus inhibition: Four novel 26-carboxylated ergostane sterols (sarcodonols A—D) isolated from S. imbricatus demonstrated antiviral activity. Sarcodonol D potently blocked HCoV-OC43 virus infection at low-micromolar concentration (IC50 = 2.26 microM; CC50 > 100 microM; selectivity index > 44.2), reducing virus-induced apoptosis through mitochondrial stress regulation.

Emerging/Preclinical

• Neurotrophic activity: Sarcodonin derivatives (sarcodonins G and A) at 25 microM showed significant neurite outgrowth-promoting activity in PC12 cells in the presence of NGF after 24 hours of treatment. This suggests potential for supporting nerve growth and repair, though data are from related Sarcodon species (S. scabrosus) rather than S. imbricatus specifically.
• Hematopoietic support: Polysaccharides from S. imbricatus activate the JAK2/STAT3 signaling pathway and enhance expression of proteins related to hematopoiesis, suggesting potential for supporting blood cell production.
• Anti-inflammatory: Cyathane diterpenoids from Sarcodon species inhibited TPA-induced ear inflammation in mouse models.
• Hypoglycemic potential: Some Sarcodon secondary metabolites have demonstrated hypoglycemic activity in preclinical models.
• Antimicrobial: Various compounds from Sarcodon species exhibit antimicrobial activity against a range of pathogenic bacteria.

Mechanism of Action

Primary Mechanisms

1. Nrf2-mediated antioxidant pathway activation: S. imbricatus extracts upregulate nuclear factor erythroid 2-related factor 2 (Nrf2), a master regulator of the antioxidant response. Nrf2 activation leads to transcription of cytoprotective genes including SOD, GSH-Px, and heme oxygenase-1 (HO-1), resulting in enhanced cellular defense against oxidative stress. This mechanism underlies both the antioxidant and anti-fatigue effects observed in mouse models.

2. Sarcodonol D antiviral mechanism: Sarcodonol D inhibits HCoV-OC43 infection by reducing virus-induced apoptosis through mitochondrial stress regulation. The compound appears to stabilize mitochondrial membrane potential and prevent cytochrome c release, blocking the intrinsic apoptotic cascade triggered by viral infection.

3. JAK2/STAT3 hematopoietic signaling: S. imbricatus polysaccharides activate the Janus kinase 2 / signal transducer and activator of transcription 3 (JAK2/STAT3) pathway, which is a critical signaling cascade for hematopoietic stem cell proliferation and differentiation. This mechanism supports blood cell production and may be relevant to recovery from myelosuppressive therapies.

Secondary Mechanisms

• NGF-enhanced neurite outgrowth: Cyathane diterpenoids (sarcodonins) from Sarcodon species modulate NGF signaling in neuronal cells, enhancing neurite extension. Sarcodonin G derivatives exhibit distinctive effects on neurite morphology by modulating specific NGF-activated signaling pathways in PC12 cells.
• NF-kB-mediated anti-inflammatory activity: Cyathane diterpenoids inhibit NF-kB signaling, reducing expression of pro-inflammatory mediators (COX-2, iNOS, TNF-alpha). This has been demonstrated for sarcodonins from S. scabrosus.
• Direct free radical scavenging: Phenolic compounds and polysaccharides in S. imbricatus directly scavenge DPPH, superoxide, and hydroxyl radicals, complementing the enzyme-mediated antioxidant effects.

Clinical Evidence Summary

No human clinical trials have been conducted specifically with S. imbricatus or its isolated compounds.

Preclinical Evidence (Selected)

Evidence Limitations

• No human clinical trials for any indication.
• The most potent compound-specific data (sarcodonols, neurite outgrowth) are from recent studies requiring replication.
• Some neurotrophic data come from related species (S. scabrosus, S. cyrneus) rather than S. imbricatus directly, though the cyathane diterpenoid skeleton is shared across the genus.
• The relationship between consuming the whole mushroom and achieving pharmacologically active concentrations of specific compounds is unknown.
• The species is mycorrhizal (forming associations with coniferous tree roots), making cultivation extremely difficult and limiting material supply for research and potential supplementation.
• Species delineation within the Sarcodon genus is complex, and some studies may not clearly distinguish between closely related species.

Safety Profile

General Assessment

S. imbricatus has a centuries-long history of safe consumption as a food mushroom across Europe and Asia. It is considered a choice edible, particularly prized in Scandinavian cuisine. No adverse effects from dietary consumption have been reported in the literature. The safety profile of concentrated extracts or isolated compounds is unknown.

Contraindications

• Fungal allergy: Individuals with known allergies to basidiomycete fungi should exercise caution.
• Pregnancy and lactation: Insufficient safety data for concentrated extracts. The whole mushroom has been consumed as food during pregnancy historically without reported issues, but concentrated preparations have not been evaluated.

Drug Interactions

• No established drug interactions. Theoretical considerations:
  • Antiviral medications: Sarcodonol D’s antiviral mechanism could theoretically interact with other antiviral agents, but this has not been studied.
  • Anticoagulants: Some mushroom polysaccharides have mild antiplatelet effects; clinical significance for S. imbricatus is unknown.

Side Effects

• As food: No documented side effects from dietary consumption of properly identified and prepared S. imbricatus.
• As extract: No side effect data from human use of concentrated extracts.

Toxicology

• No formal toxicological studies specific to S. imbricatus extracts or isolated compounds have been published.
• The mushroom is classified as edible with no reported toxicity at dietary consumption levels.
• Some Sarcodon species (particularly S. scabrosus) can be bitter; S. imbricatus is generally considered mild to slightly bitter when young.

Identification Caution

Wild-harvested S. imbricatus must be carefully identified, as it can be confused with other Sarcodon and Hydnellum species, some of which are inedible or have unknown safety profiles. Key identification features include large brown scales on the cap and spore-bearing teeth (spines) underneath rather than gills.

Clinical Dosage

No Established Clinical Dosage

No human clinical dosage recommendations exist for S. imbricatus as a medicinal preparation.

Dietary Consumption

• Fresh: Consumed cooked in various European cuisines; typical portion 100—200 g fresh weight
• Dried: Used in soups and stews in Scandinavian and Eastern European cooking traditions
• Preparation note: Young specimens are preferred for culinary use; older specimens may develop bitter taste

Preclinical Reference

• Sarcodonol D antiviral activity: IC50 = 2.26 microM in cell culture. Translation to oral dosing in humans has not been determined.
• Anti-fatigue mouse study: Dosing regimen used powdered dried fruiting bodies administered orally to mice. Human-equivalent dosing has not been established.

Sources

• Wang J, Zhang Y, Yuan Y, Yue T. Immunomodulatory of polysaccharide from Sarcodon imbricatus on cyclophosphamide-induced immunosuppressed mice. Food Sci Technol. 2014;42:33-42
• Wang M, Gao J, Shen F, Zhang X, Wang Q, Zhang M. Antifatigue potential activity of Sarcodon imbricatus in acute exercise-treated and chronic fatigue syndrome in mice via regulation of Nrf2-mediated oxidative stress. Oxid Med Cell Longev. 2018;2018:9140896
• Kim JY, Kim DH, Lee YR, Lee HJ, Jang MJ, et al. Sarcodonol A-D from fruiting bodies of Sarcodon imbricatus inhibits HCoV-OC43 induced apoptosis in MRC-5 cells. Biomed Pharmacother. 2024;170:116076
• Marcotullio MC, Oball-Mond Mwankie GN, Cossignani L, Tirillini B, Pagiotti R. Phytochemical analysis and antiradical properties of Sarcodon imbricatus (L.:Fr) Karsten. Nat Prod Commun. 2008;3(11):1907-1910
• Ma BJ, Shen JW, Yu HY, Ruan Y, Wu TT, Zhao X. Hericenones and erinacines: stimulators of nerve growth factor (NGF) biosynthesis in Hericium erinaceus. Mycology. 2010;1(2):92-98
• Ohta T, Kita T, Kobayashi N, Obara Y, Nakahata N, Ohizumi Y. Anti-inflammatory and neurite outgrowth activities of sarcodonin G derivatives from Sarcodon scabrosus. Biol Pharm Bull. 2008;31(5):953-957
• Ma K, Bao L, Han J, Jin T, Yang X, Zhao F, et al. Exploring the molecular tapestry of Sarcodon secondary metabolites: chemical structures, activities, and biosynthesis. Mycosphere. 2024;15:4190-4240
• Dong Z, Liu Y, Xu G, Zhang J, Chen Z, Xu N. Polysaccharides from Sarcodon imbricatus activate the JAK2/STAT3 signalling pathway. J Funct Foods. 2018;49:251-260
• Kolundric V. Sarcodon imbricatus (L.) P. Karst. In: Medicinal Mushrooms. Springer; 2023:651-662

Connections

• Lion’s Mane (Hericium erinaceus): Lion’s Mane shares the neurite outgrowth-promoting activity through distinct compounds (hericenones and erinacines vs. sarcodonins). Both genera produce cyathane-type diterpenoids, placing them in a select group of fungi with demonstrated neurotrophic potential. A complementary pairing for neurocognitive support.
• Chaga (Inonotus obliquus): Chaga shares the antioxidant emphasis through complementary mechanisms (betulinic acid and melanin vs. Nrf2-mediated enzyme upregulation). Both are forest-dwelling fungi prized in northern cultures.
• Shiitake (Lentinula edodes): Shiitake is another widely consumed edible mushroom with established immunomodulatory polysaccharide pharmacology (lentinan), providing a comparison point for S. imbricatus polysaccharide research.
• Maitake (Grifola frondosa): Maitake polysaccharides share the JAK/STAT signaling activation mechanism relevant to immune and hematopoietic support.
• Turkey Tail (Trametes versicolor): Turkey Tail provides complementary beta-glucan immune activation and represents the clinical evidence benchmark for mushroom-derived immunomodulatory therapy.
• Reishi (Ganoderma lucidum): Reishi offers complementary triterpenoid-based anti-inflammatory activity alongside the diterpenoid pharmacology of S. imbricatus.