Parkinson's disease (PD), also known as parkinsonism, is a complex neurodegenerative disease (also known as cognitive disorder) second only to Alzheimer's disease , which mainly affects the neurons of dopamine production (dopaminergic) in specific areas of the brain (substantia nigra). The disease can cause progressive dyskinesia and non-dyskinesia. Clinical symptoms are bradykinesia, trembling at rest or stiffness .
3. Pathogenesis of Parkinson's Disease
There are several theories:
- Mitochondrial dysfunction;
- Oxidative stress;
- Abnormal aggregation of proteins;
- Immunoinflammatory mechanisms.
In conclusion, multiple factors in the above pathogenesis synergize, mutually cause and effect each other, and the vicious cycle leads to selective destruction of substantia nigra neurons, neurobiochemical changes such as dopamine synthesis and secretion reduction, as well as a series of changes in basal ganglia loop, and eventually a variety of clinical manifestations of Parkinson's disease.
3.1 Parkinson's Disease Causes
Although the etiology of Parkinson's disease is still under investigation and has not been fully established, the absence of neurotransmitter dopamine is the main cause. It is also related to genetic factors, environmental factors, patient factors and so on.
Figure 3 The main cause of Parkinson's disease
Pathogenic mutations of autosomal dominant Parkinson's disease genes SNCA, LRRK2 and VPS35 account for about 0.1% to 30% of Parkinson’s disease, which depends on family history, age of onset and population background  .
Autosomal recessive inheritance: PARK7, PINK1, PRKN.
Mutations in the gene encoding glucocerebrosidase are the strongest genetic risk factors for this disease .
The enrichment of rare inherited variation in the pathway controlling mitochondrial DNA replication and repair influences the risk of PD，Most mutations in genes that cause familial PD, including SNCA , LRRK2, PINK1, PRKN, and VPS35, have been shown to disrupt mitochondrial quality control. The induction of Parkinson phenotype in zebrafish larvae supports the contribution of mitochondrial superoxide generation to PD development .
Nervous system problems: supranuclear palsy, Wilson's disease, Huntington's disease, Haller Walden-Spartz syndrome, and Alzheimer's disease can also cause Parkinson's disease.
Brain injury: traumatic brain injury, which causes changes in consciousness levels, increases the risk of PD in the years following injury .
Living area: there are differences in the geographical distribution of PD. This may be due to differences in environmental and genetic risk factors.
Occupations: certain occupational categories or titles are associated with higher rates of PD. Stress at work increases the risk of Parkinson's disease.
Pesticide exposure: Pesticides (including cypermethrin and hexachlorocyclohexane) have been reported most consistently in all chemical exposures associated with Parkinson's disease.
Contact with metals: Occupational exposure to various metals is considered to be related to the development of PD.
Age: is the biggest risk factor for Parkinson's disease. Parkinson's disease mainly affects the elderly, especially those between the ages of 55 and 65.
Gender: men are more likely than women to develop Parkinson's disease.
6. Parkinson's Disease Treatment
Treatment can be divided into non-drug treatment and drug treatment, surgical treatment.
6.1 Medical Treatment
Parkinson's disease medications list:
- Anticholinergic drugs
- Compound levodopa
- DR agonist
- MAO - B inhibitors
- COMT inhibitors
6.2 Surgical Treatment
Such as deep brain stimulation or tissue resection.
6.3 Non - Pharmacological Treatments
Non - pharmacological treatments includes awareness and understanding of the disease, nutritional supplements, exercise enhancement, confidence in combating the disease, and understanding, care and support from society and family.
Natural Treatment of Parkinson's Disease
A healthy and balanced diet can improve overall health. Many people with Parkinson's disease, including the famous advocate Michael J. Fox, say that a healthy diet helps to alleviate symptoms.
Parkinson's disease diet: The ketogenic diet may even be beneficial for diabetes, cancer, epilepsy and Alzheimer's disease  ; Green tea may have a protective effect on neurons; people who drink coffee  are at a much lower risk of developing Parkinson's disease.
Supplements: Certain supplements may help reduce Parkinson's symptoms, including:
- Vitamins C, E and D
- Coenzyme 10
- Ω - 3 fatty acids
- Antioxidant supplements
- Essential oils
- Increase fiber intake to reduce constipation.
Reduce toxicity and chemical exposure: Studies have shown that rural living, well water exposure, pesticide and herbicide exposure are all linked to Parkinson's disease, so eating more or all organic food is very beneficial and protective. Chelation also helps reduce the accumulation of heavy metals and the presence of other toxins.
Exercise therapy may be helpful in improving the symptoms of Parkinson's disease and even delaying the progression of the disease . Patients with Parkinson's disease often have gait freezing, posture balance disorder, language and/or dysphagia, and can perform rehabilitation or exercise training according to different mobility disorders. Perform language barrier training, gait training, posture balance training, etc. Exercise and physical therapy are key to gait and balance symptoms that cannot be improved with medication.
Patients with Parkinson's disease often have psychological disorders such as depression, which is one of the main risk factors affecting the quality of life of patients. Therefore, effective psychological counseling and antidepressant medication for patients with Parkinson's disease can achieve a more satisfactory therapeutic effect.
In addition, there are music therapy  and speech therapy for Parkinson's disease .
Future Directions for Parkinson's Treatment
Gene therapy may be a promising PD treatment strategy. In recent years, several gene therapy methods for PD have entered clinical trials. Some gene therapy methods for PD include:
- AADC-TH-GCH gene therapy
- Viral vector-mediated gene delivery
- RNA interference therapy
- CRISPRS-CAS9 gene editing system
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