Reishi and The Nervous System
Eshed Haklai

​

Reishi and Neurodegenerative Diseases:

Neurodegenerative diseases of the nervous system include Alzheimer’s disease, Parkinson’s disease, multiple sclerosis, Huntington’s disease, and others. These conditions share several pathological features: oxidative stress, mitochondrial dysfunction in neurons, and protein aggregation and deposition. Polysaccharides from Reishi, ganoderic acids, and additional compounds found in the mushroom have been shown to reduce oxidative damage and may promote processes that improve neuronal function. Most of the evidence comes from cell culture and animal studies, and clinical studies in humans are still lacking. Below are findings related to three well-studied conditions: multiple sclerosis, Alzheimer’s disease, and Parkinson’s disease.

Multiple Sclerosis (MS)
Brief overview of the disease:
In multiple sclerosis, the immune system attacks myelin, the insulating layer that surrounds neuronal axons and enables rapid signal transmission. When myelin is damaged, electrical signaling in neurons is impaired, and in some cases the axons themselves and even entire neurons may be damaged. Disrupted signal conduction leads to weakness, numbness, difficulty walking, and progressive functional decline. In addition, MS involves neuroinflammation, characterized by activation of immune cells within the nervous system that secrete inflammatory mediators (pro-inflammatory cytokines). This inflammation causes further neuronal damage. These immune cells include microglia (resident immune cells of the brain and spinal cord) and other glial cells, which support neurons, maintain homeostasis, and assist in myelin repair.

Example studies on Reishi and MS:

1. A 2020 mouse study examined the effects of Reishi capsules in mice with MS. Researchers assessed disease symptoms, nervous system damage, microglial activation, the degree of myelin destruction (demyelination), inflammatory mediator expression, and related proteins. The results showed that Reishi reduced disease progression, decreased inflammation, suppressed microglial activation, supported glial cells, and improved myelin integrity.
The study concluded that Reishi has neuroprotective potential in MS, acting as an immunomodulatory mushroom that supports the nervous system.

2. A microglial cell culture study examined the effects of an alcoholic extract of Reishi on inflammatory development. The cells were first stimulated with a pro-inflammatory agent and then treated with the extract. The results showed that Reishi reduced inflammatory mediators and inhibited inflammatory pathways in neural cells.
The conclusion was that Reishi suppresses microglial inflammatory activity and supports a healthier neural environment, potentially reducing neural damage in MS.

Important note:

• All current evidence regarding Reishi and MS comes from cell culture and animal studies. There are no significant clinical trials in humans yet.

• The findings suggest that Reishi may:
  Reduce neuroinflammation by inhibiting microglial activation
  Support glial cells and myelin repair
  Slow neuronal damage in multiple sclerosis

​

Alzheimer’s Disease (AD)
Brief overview of the disease:
Alzheimer’s disease is characterized by the accumulation of β-amyloid and tau proteins in the brain. These aggregates damage neurons and impair brain regions involved in memory and learning.
In addition, the disease involves neuroinflammation, increased oxidative stress (generation of harmful free radicals), and mitochondrial dysfunction (impairment of the cell’s energy center).
Together, these processes lead to memory decline, cognitive impairment, and eventually deterioration of daily functioning.

Example studies on Reishi and Alzheimer’s disease:

1. A study in Alzheimer’s mice and neuronal cell cultures examined the effects of Reishi polysaccharides on cognitive performance, neural progenitor cell proliferation and survival, and activation of the FGFR1/ERK/AKT pathway.
The FGFR1/ERK/AKT pathway is a molecular signaling pathway in neurons that supports cell survival, proliferation, and neuronal regeneration. Its activation promotes neurogenesis and maintenance of existing neurons.
The researchers found that Reishi improved cognitive performance, increased the number of neural progenitor cells, and activated survival and regeneration pathways.
The conclusion was that Reishi has potential to support neurogenesis and neuroprotection in Alzheimer’s disease.

2. An April 2025 study examined the effects of Reishi polysaccharides in Alzheimer’s mouse models. Measurements included β-amyloid and tau protein levels, antioxidant activity, and mitochondrial function. The results showed that Reishi polysaccharides reduced β-amyloid and tau levels, enhanced antioxidant activity, and helped restore mitochondrial balance.
The study concluded that Reishi may contribute to reducing oxidative damage and improving mitochondrial function in Alzheimer’s disease.

Summary - Alzheimer’s disease:

• Studies suggest that Reishi protects against Alzheimer’s pathology through reduction of inflammation and oxidative damage, and by promoting neurogenesis

• Reishi activates the FGFR1/ERK/AKT signaling pathway

• Reishi reduces β-amyloid and tau protein levels, thereby protecting neurons

• Animal studies show improvements in learning and memory, but clinical human studies are still lacking
   

Parkinson’s Disease (PD)
Brief overview of the disease:
In Parkinson’s disease, dopaminergic neurons in a brain region known as the basal ganglia progressively degenerate. The basal ganglia are a group of deep brain nuclei located beneath the cerebral cortex. They do not directly activate muscles but are responsible for planning, refining, and regulating movement through dopaminergic signaling. Neuronal damage in Parkinson’s disease involves microglial inflammation, oxidative stress, mitochondrial dysfunction, and aggregation of proteins such as α-synuclein.
Clinically, this leads to tremor, slowed movement, rigidity, and balance disturbances.

Example studies on Reishi and Parkinson’s disease:

1. Cell culture studies involving microglia and dopaminergic neurons examined the effects of Reishi extract under inflammatory conditions. The findings showed that Reishi reduced inflammatory cytokines, inhibited microglial activity, and protected dopaminergic neurons.
The conclusion was that Reishi can suppress microglial inflammation and support dopaminergic neurons, potentially slowing Parkinson’s disease progression.

2. An animal study using MPTP-induced Parkinsonism (a toxin that selectively damages dopaminergic neurons) treated mice with Reishi extract.
Researchers assessed motor function, expression of tyrosine hydroxylase (TH), a key enzyme in dopamine synthesis, and mitochondrial markers. The results showed improved motor performance, preservation of TH expression, enhanced mitochondrial function, and reduced dopaminergic cell death. The researchers concluded that Reishi demonstrated clear neuroprotective effects in a Parkinson’s disease model.

Summary - Parkinson’s disease

• Reishi reduces dopaminergic neuron loss, primarily by decreasing oxidative stress and neuroinflammation

• Reishi modulates microglial activity

• Several animal studies show improved motor function and survival of dopaminergic neurons​