Parkinson's Disease: Most Effective Supplements

Parkinson's disease is a degenerative disease of the central nervous system, primarily affecting people over 50. It is characterized by the progressive loss of dopaminergic neurons in the substantia nigra of the midbrain, an essential region for coordinating movements. It is the second most common neurodegenerative disease after Alzheimer's disease. Chronic, progressive, and currently incurable, it leads to various symptoms, both motor and non-motor, which gradually impair patients' quality of life.

Origin and Pathophysiology

Parkinson's disease results from the degeneration of neurons producing dopamine, a key neurotransmitter for movement regulation. These neurons, normally numbering 500,000 in the substantia nigra (or locus niger), drastically reduce as the disease progresses. When their number falls below the critical threshold of 100,000, dopaminergic transmission is no longer sufficient to suppress the excessive activity of cholinergic neurons. This cholinergic hyperactivity stimulates areas like the thalamus, globus pallidus, and cortex, causing characteristic motor disorders. The causes of this degeneration include several biological mechanisms: oxidative stress, mitochondrial anomalies, glutamate excitotoxicity, disturbance of trophic factors, and chronic inflammation. Additionally, the abnormal accumulation of the protein α-synuclein in neurons, forming Lewy bodies, is a key marker of the disease. These pathological aggregates disrupt the functioning of dopaminergic neurons and other neural systems, such as those involving acetylcholine, serotonin, and noradrenaline.

Etiology and Risk Factors

Parkinson's disease is of multifactorial origin, combining genetic and environmental factors. Mutations in certain genes (notably involved in juvenile or early-onset forms) play a role, as do environmental exposures to pesticides, herbicides, or heavy metals. Repeated head trauma, such as that seen in boxers, are also risk factors. Some dietary behaviors, such as excessive consumption of iron-rich meats or animal fats, also increase risks. Conversely, studies suggest a protective effect of substances like caffeine, though these results are not yet fully confirmed.

Clinical Symptoms

Parkinson's disease manifests through motor and non-motor symptoms that evolve over time. The motor symptoms include: • Resting tremors: Primarily affect hands and feet, often unilateral at first. These tremors disappear during purposeful movements and while sleeping, but worsen with stress or fatigue. • Muscular hypertonia: Muscle rigidity manifests, often described as a "cogwheel" sensation during passive movements. • Bradykinesia: Movements become slow and clumsy, with a loss of precision, such as in writing. • Akinesia: Difficulty initiating movements, loss of automatic movements (e.g., arm swing while walking), and a fixed facial expression. The non-motor symptoms include: These symptoms, sometimes present several years before motor manifestations, include: • Olfactory disturbances. • Sleep disorders (insomnia, periodic leg movements). • Gastrointestinal problems (constipation), urinary issues, and orthostatic hypotension. • Cognitive and psychiatric symptoms: depression, anxiety, irritability, and in advanced stages, dementia.

Diagnosis

Diagnosis is primarily based on clinical examination, focusing on characteristic motor symptoms (resting tremor, bradykinesia, hypertonia). Asymmetry of symptoms and a favorable response to levodopa strengthen the diagnosis. Imaging exams, such as dopamine transporter scintigraphy, may be used to resolve doubts. Scales like the UPDRS (Unified Parkinson’s Disease Rating Scale) help evaluate clinical status and treatment efficacy.

Treatments

The treatment of Parkinson's disease aims to alleviate symptoms and improve quality of life. Current approaches include: • Levodopa: Converted to dopamine in the brain, it is the reference treatment. • Dopaminergic agonists: Directly stimulate dopamine receptors. • Monoamine oxidase B inhibitors: Prolong the effect of dopamine by reducing its breakdown. • Non-motor symptom treatment: Medications for constipation, insomnia, or mood disorders. • Deep brain stimulation: A technique reserved for advanced cases, where electrodes implanted in the brain reduce tremors and rigidity. There are complementary measures: • Physiotherapy and rehabilitation to improve mobility. • Adapted physical activity to maintain flexibility and reduce posture issues. • A balanced diet, rich in antioxidants, to combat oxidative stress.

Prevention and Outlooks

No effective preventive measures have been recognized to date, but certain habits could reduce risks: adopting a diet rich in B vitamins and antioxidants, and avoiding prolonged exposure to pesticides or heavy metals. Current research explores new therapeutic avenues, notably on inflammatory mechanisms, trophic factors, and gene therapies, offering hope for treatments that modify the disease's progression in the near future.