Memorize that Mushroom

Mushrooms are nutritious and offer a panoply of potent medicinal and immune boosting compounds as well as tastes and textures to satisfy even the pickiest palate.1

According to a 2014 review article of research on over 20 different culinary medicinal mushrooms with a reputation for enhancing cognition, mushrooms can reduce beta amyloid-induced toxicity, help stimulate nerve growth factor (NGF), are neuroprotective and antioxidant.2 “Mushrooms offer great potential,” the researchers conclude, “because of the complexity of their chemical contents and different varieties of bioactivities. Available evidence suggests that mushrooms exhibit antioxidant, anti-tumor, antivirus, anti-cancer, anti-inflammatory, immune modulating, anti-microbial, and anti-diabetic activities.”2

One mushroom in particular is known for its ability to regenerate neurons and improve learning and memory. It is called Lion’s mane (Hericium erinaceus), and is very popular in China and Japan. When eaten, is usually often served browned and crisp after sautéing in butter or olive oil.

In a study of 30 clinically healthy Japanese men and women with mild cognitive impairment, Lion's mane offered a significant memory boost.

Lion’s mane has been a staple of Chinese medicine for a thousand years. It contains two novel nerve growth factors (NGF)—known as hericenones (aromatic compounds found in the fruit body) and erinacines (found in the mycelium)—that are neuroregenerative, stimulating the growth and re-myelination of neurons.3 Myelin is the protective sheath that surrounds a neuron, and can degenerate with age or neurodegenerative illness. Both hericenones and erinacines easily cross the blood-brain barrier.4

In 1991, Dr. Hirozaku Kawagishi of Shizuoka University in Japan first identified these two nerve growth factors, and found that they stimulated mouse astroglial cells (astroglial cells are specialized non-neuronal cells that form myelin, and provide support and protection for neurons5) to produce NGF.6 Since that time, he writes, “We have been engaged in a study to search for NGF synthesis-promoting agents in medicinal mushrooms… bioactive substances…that induce the synthesis of NGF…” The enhancement of NGF production, he notes, would be beneficial for disorders of the central and peripheral nervous system.7

Back in 1994, Kawagishi found that erinacines significantly induced the synthesis of NGF in vitro.8 As recently as 2015, his work has been confirmed. Both H. erinaceus and another mushroom, Lignosus rhinocerotis (Tiger milk mushroom), stimulate neurite outgrowth in brain, spinal cord, and retina cells, resulting in neuronal differentiation and neuronal elongation.9 In animal studies, H. erinaceus led to functional recovery of nerve injury by stimulating neuron regrowth, and improved the myelination process in the rat brain.10,11 It was also neuroprotective and stimulated NGF biosynthesis in a stroke model in mice.12

A 2011 study of an Alzheimer’s model in mice produced remarkable results. Mice were injected with neurotoxic peptides, which led to amyloid plaque formation similar to that seen in Alzheimer’s patients. The mice were challenged by a maze designed for testing memory. Mice that developed plaque could no longer memorize the maze. But when they were fed a diet containing 5 percent dried lion’s mane mushrooms for 3 weeks, the mice performed significantly better and spent more time exploring new objects in their environment.13 Finally, in a 2015 study, H. erinaceus enhanced nerve regeneration and accelerated functional recovery after crush injury in rats. The researchers conclude that “the neurotherapeutic effects of the polysaccharide [in the mushroom] was comparable to those elicited by mecobalamin, a drug used in peripheral nerve disorders.”14

Research in humans is equally tantalizing. In 2009, a double-blind, placebo controlled study on 30 clinically healthy Japanese men and women, aged 50 to 80 years old, found that H. erinaceus significantly boosted memory. The men and women took four tablets three times a day, containing either placebo or 250 mg each of lion’s mane dry powder. The study lasted for 22 weeks—2 weeks of initial examination, 16 weeks taking the tablet, and 4 weeks of follow-up. At weeks 8, 12 and 16 of the trial, those on H. erinaceus showed significantly increased scores on a cognitive function scale compared with the placebo group. The effect diminished within four weeks of the conclusion of the intake period. The results obtained in this study suggest that H. erinaceus is effective in improving mild cognitive impairment.15

A study in a rehabilitative hospital in Japan looked at the effect of 5 grams of dried lion’s mane daily for six months. The mushroom was added to their daily soup. Six out of seven showed improvements in perceptual ability, and all seven showed improvements in their overall functional independence score.10 Hericium erinaceus may even boost mood and memory in healthy individuals. A 2010 double-blind, placebo-controlled study of thirty post-menopausal women found that concentration improved, while depression and anxiety declined.16

Altogether, lion’s mane is a remarkable functional food, one with a long history of culinary and medical use. As summed up in a 2015 study from researchers at Henan Agricultural University in China: “Hericium erinaceus and its components could be useful as potent protective agents for neurodegenerative disorders.”17 Lion’s mane, it seems, is a powerful superfood for the brain.

References

  1. Stamets, P., Notes on nutritional properties of culinary-medicinal mushrooms. International Journal of Medicinal Mushrooms. 2005; 7:109-116.
  2. Phan CW, David P, Naidu M, Wong KH, Sabaratnam V. Therapeutic potential of culinary-medicinal mushrooms for the management of neurodegenerative diseases: diversity, metabolite, and mechanism. Crit Rev Biotechnol. 2015;35(3):355-68. PMID: 24654802 View Abstract
  3. Ma, Bing-Ji , Jin-Wen Shen, Hai-You Yu, Yuan Ruan, Ting-Ting Wu & Xu Zhao, 2010. Hericenones and erinacines: stimulators of nerve growth factor (NGF) biosynthesis in Hericium erinaceus. Mycology: An International Journal on Fungal Biology. 1(2): 92-98.
  4. Ma BJ, Shen JW, Yu HY, Wu TT, Ruan Y, Wu TT, Zhao X. Hericenones and erinacines: stimulators of nerve growth factor (NGF) biosynthesis in Hericium erinaceus. Mycology: An International Journal on Fungal Biology. 1:2, 92-98 (2010).
    66 Belanger M & Magistretti P. The role of astroglia in neuroprotection. Dialogues Clin Neurosci. 2009 Sep; 11(3): 281–295. PMCID: PMC3181926 View Abstract
  5. Belanger M & Magistretti P. The role of astroglia in neuroprotection. Dialogues Clin Neurosci. 2009 Sep; 11(3): 281–295. PMCID: PMC3181926
  6. Kawagishi, H., Ando, M., Sakamoto, H., Yoshida S., Ojima, F., Ishiguro, Y., Ukai, N., Fukukawa, S. 1991. Hericenone C, D and E, stimulators of nerve growth factor (NGF) synthesis from the mushroom Hericium erinaceum. Tetrahedron Lett 32, 4561-4564.
  7. Kawagishi H, Lion’s Mane: the anti-dementia effect of lion’s mane (Hericium erinaceum) and its clinical application. Townsend Letter for Doctors and Patients, April 2004.
  8. Kawagishi H, Shimada A, Shirai R, et al. (1994). Erinacines A, B and C, strong stimulators of nerve growth factor (NGF)-synthesis, from the mycelia of Hericium erinaceum. Tetrahedron Lett, 35, 1569–72.
  9. Samberkar S, Gandhi S, Naidu M, Wong KH, Raman J, Sabaratnam V.Lion’s Mane, Hericium erinaceus and Tiger Milk, Lignosus rhinocerotis (Higher Basidiomycetes) medicinal mushrooms stimulate neurite outgrowth in dissociated cells of brain, spinal cord, and retina: an in vitro study. Int J Med Mushrooms. 2015;17(11):1047-54. PMID: 26853959 View Abstract
  10. Wong KH, Naidu M, David RP, et al. (2009). Functional recovery enhancement following injury to rodent peroneal nerve by lions mane mushroom, Hericium erinaceus (Bull.: Fr.) Pers. (Aphyllophoromycetideae). Int J Med Mushrooms, 11, 225–36.
  11. Moldavan M, Grygansky AP, Kolotushkina OV, et al. Neurotropic and trophic action of Lion’s Mane Mushroom Hericium erinaceus (Bull.: Fr.) Pers. (Aphyllophoromycetideae) extracts on nerve cells in vitro. Int J Med Mushrooms. (2007) 9, 15–28.
  12. Hazekawa M, Kataoka A, Hayakawa K, Uchimasu T, Furuta R, Irie Y, Akitake Y, Yoshida M, Fujioka T, Egashira N, Oishi R, Mishima K, Mishima T, Iwasaki K, Fujiwara M. Neuroprotective effect of repeated treatment with Hericium erinaceumin mice subjected to middle cerebral artery occlusion, J. Health Sci., 2010, 56, 296–303.
  13. Mori, K., Obara, Y., Moriya, T., Inatomi, S., Nakahata, N. 2011. Effects of Hericium erinaceus on amyloid β(25-35) peptide-induced learning and memory deficits in mice. Biomed Res. 32(1):67-72. PMID: 21383512 View Abstract
  14. Wong KH, Kanagasabapathy G, Bakar R, Phan CW. Restoration of sensory dysfunction following peripheral nerve injury by the polysaccharide from culinary and medicinal mushroom, Hericium erinaceus (Bull.: Fr.) Pers. Through its neuroregenerative action. Food Sci. Technol. 2015.
  15. K, Inatomi S, Ouchi K, Azumi Y, Tuchida T. Improving effects of the mushroom Yamabushitake (Hericium erinaceus) on mild cognitive impairment: a double-blind placebo-controlled clinical trial. 2012 Phytother Res. 2009 Mar;23(3):367-72. PMID: 1884432 View Abstract
  16. Nagano, M., Shimizu, K., Kondo, R., Hayashi, C., Sato, D., Kitagawa, K., Ohnuki, K. 2010. “Reduction of depression and anxiety by 4 weeks Hericium erinaceus intake.” Biomed Res. 31(4):231-7. PMID: 20834180 View Abstract
  17. Phan CW, Lee GS, Long SL, Wong YT, Brkljača R, Urban S, Malek SNA, Sabaratnam V. Hericium erinaceus (Bull.: Fr) Pers. cultivated under tropical conditions: isolation of hericenones and demonstration of NGF-mediated neurite outgrowth in PC12 cells via MEK/ERK and PI3K-Akt signaling pathways Food Funct. 2014 Dec;5(12):3160-9. PMID: 25288148 View Abstract