Medicinal Mushrooms have become a hot item in the mass media in the last few years but the information being disseminated about them is not always scientifically accurate. Most of the studies on the efficacy of medicinal mushrooms that are available to the public are based on animal studies (usually in mice) or cultured cells. In these cases, the bioactivity of the mushroom extracts cannot always be correlated to their activity when ingested by humans--either orally or by injection.
Our research on components of Lion's Mane mushroom (Hericium erinaceum) and their biological activities in cell culture is a case where positive antidementia results in the laboratory have been confirmed by analogous results in human use. In this article, we will introduce both the results from the laboratory and their clinical application.
Conventional Treatments of Alzheimer's Disease
Alzheimer's disease is primarily a disorder of aging in which individuals become agitated and uncomprehending, with profound loss of cognitive function, ultimately requiring institutionalization. About 1 in 10 people over the age of 65 and as many as 5 out of 10 people over the age of 85 are affected. This disease is characterized biologically by the death of neurons in the forebrain, hippocampus, and cerebral cortex.
The most conventional approach to treatment of Alzheimer's disease currently in practice is to treat the symptoms caused by the death of cholinergic neurons. Four pharma-ceutical products approved by the FDA that are presently on the market work by potentiating neurotransmission at cholinergic synapses. These drugs are: Aricept[R] by Pfizer, Exelon[R] by Novartis, Reminyl[R] by Janssen, and Cognex[R] by First Horizon. None of these products, however, reverses the damage done to cognitive functioning. They simply delay further deterioration. Recently, a new drug called memantine, produced by Forest Laboratories, was approved for use by the FDA. Memantine works by blocking the receptor for the glutamate neurotransmitter whose overactivity may be responsible for the neurotoxicity of Alzheimer's disease. Likewise, its beneficial effect is only temporary.
Inducers of Nerve Growth Factor Synthesis in vitro
One of the major new approaches to the study of treatments for Alzheimer's disease concerns the search for agents that stimulate Nerve Growth Factor (NGF) production in the brain. NGF is part of a family of proteins that play a role in the maintenance, survival and regeneration of neurons during adult life. Its absence in the adult brain of mice leads to a condition resembling Alzheimer's disease.
Nerve Growth Factor itself cannot be used as an orally administered drug to regenerate brain tissue because it does not cross the blood-brain barrier. If bioactive substances with low molecular weight can be found that penetrate the barrier and induce the synthesis of NGF inside the brain, such substances may be applied as oral agents to prevent this disease. Even if these substances cannot go through the barrier, the enhancement of...