Parkinson disease (PD) is considered a multisystemic neurodegenerative disorder, together with the classic motor disability, and a number of non-motor symptoms (NMS).NMS have a significant negative relation with patients' quality of life. In general, both medicinal and nonmedicinal therapies are often advised for PD patients with NMS, but robust evidences for underpinning the clinical effects are limited. Recently, the search for small preventative neurotrophic compounds that are responsible for the maintenance, survival of neurons has attracted much attention. Erinacine A, which is extracted from Hericium erinaceus is the one showed prominent beneficial effects in the central nervous system. It can increase NGF and catecholamine content in the locus coeruleus and hippocampus of rats. This markedly increases neuronal survival in different brain areas and substantially improve behavioral outcomes in various animal models. In a MPTP-induced Parkinsonism model, treatment with Hericium erinaceus mycelium reduced the loss of dopaminergic cell, eliminated neuronal apoptosis and reversed MPTP-associated motor deficits. Thus, this project intends to hold a randomized, controlled trial to assess the effect of Hericium erinaceus mycelium, which is enriched of Erinacine A, in NMS of PD. This project will enroll 80 patients with PD. Subjects will be randomly allocated into study or placebo group. Subjects will take Hericium erinaceus mycelium for 2 years (one capsule per meal per day) and their treatments for PD will not be altered.

Inclusion criteria:

1. PD patients aged 50-79 years diagnosed by neurologist (should exclude vascular parkinsonism, secondary parkinsonism( including toxin, drug, heavy metal, CO intoxication), normal pressure hydrocephalus, multiple system atrophy, progressive supranuclear palsy, cortical basal degeneration, dementia with Lewy Body, hereditary parkinson's disease with genetic mutation, Huntington's disease, Wilson disease, spinal cerebellar ataxia with extrapyramidal syndrome, essential tremor, dystonia)
2. PD at Hoehn and Yahr stage 2-2.5
3. without cognitive decline

Exclusion criteria:

1. with diabetes mellitus (DM)
2. with nephropathy (GFR < 30ml/min)
3. with significant neurological deficits caused by vascular insults

Measurement parameters:

1. At recruitment: blood sugar, AST, ALT, BUN, Crea, Ca, Na, K and peripheral blood cell (for the expression levels of KATP)
2. every 6 months: motor symptoms: UPDRS, evaluate with UDYSRS if presence with dyskinesia Non motor symptoms: self-report: PDQ39, QUIP, PDSS Rated by neurologist: NMSS, HAM-D, BPRS
3. every 1 year: CASI, tilting table, AST, ALT, BUN, crea, Na, K, Ca

Protocol:

0 month (initial baseline):

1. blood sugar, AST, ALT, BUN, Crea, Ca, Na, K and peripheral blood cell
2. Tilting table test (autonomic function)
3. CASI cognitive test
4. UPDRS, evaluate with UDYSRS if presence with dyskinesia Non motor symptoms: self-report: PDQ39, QUIP, PDSS Rated by neurologist: NMSS, HAM-D, BPRS
5. stool microbiota

6 months: UPDRS, evaluate with UDYSRS if presence with dyskinesia Non motor symptoms: self-report: PDQ39, QUIP, PDSS Rated by neurologist: NMSS, HAM-D, BPRS

12 months:

1. UPDRS, evaluate with UDYSRS if presence with dyskinesia Non motor symptoms: self-report: PDQ39, QUIP, PDSS Rated by neurologist: NMSS, HAM-D, BPRS
2. CASI cognitive test, tilting table, AST, ALT, BUN, crea, Na, K, Ca

18 months: UPDRS, evaluate with UDYSRS if presence with dyskinesia Non motor symptoms: self-report: PDQ39, QUIP, PDSS Rated by neurologist: NMSS, HAM-D, BPRS

24 months:

1. UPDRS, evaluate with UDYSRS if presence with dyskinesia Non motor symptoms: self-report: PDQ39, QUIP, PDSS Rated by neurologist: NMSS, HAM-D, BPRS
2. CASI cognitive test, tilting table, AST, ALT, BUN, crea, Na, K, Ca
3. stool microbiota

Inclusion Criteria:

• idiopathic PD patients, aged 50-79 years
• modified Hoehn & Yahr stage 2-2.5
• Without subjective and objective cognitive decline (objective cognitive decline will be determined by CASI)

Exclusion Criteria:

• With diabetes
• With end stage renal disease under hemodialysis
• With significant vascular insults that resulted in significant neurological deficits