15.5: Parkinson’s Disease: Overview

Neurodegenerative disorders are progressive diseases that cause irreversible damage and loss to neurons in specific brain areas. Examples of these disorders include Parkinson's disease, Alzheimer's disease, Multiple Sclerosis (MS), and Amyotrophic Lateral Sclerosis (ALS). These disorders share characteristics such as proteinopathies, selective neuronal vulnerability, and a complex interplay between genetic and environmental factors. The primary therapeutic goal for these conditions is to alleviate symptoms and slow the progression of the underlying neurodegenerative process, even though a cure remains elusive.

Parkinsonism is a clinical syndrome involving bradykinesia, muscular rigidity, resting tremor, and impaired postural balance. The most predominant Parkinsonism is idiopathic Parkinson's disease, featuring degeneration of dopaminergic neurons in the substantia nigra region of the brain. Pseudoparkinsonism, on the other hand, mimics the symptoms of Parkinson's but is usually caused by certain dopamine-disrupting medications like haloperidol and phenothiazine or other health conditions. The pathophysiology of Parkinson's disease involves basal ganglia dysfunction and an imbalance between direct and indirect neural pathways. This disease's primary pathological feature includes Lewy bodies and intracellular inclusions containing aggregated α-synuclein proteins.

Treatment for Parkinsonism primarily uses levodopa (L-DOPA), a dopamine precursor that increases its levels in the brain, helping to manage the symptoms. It may be used in conjunction with carbidopa (Lodosyn). Ongoing research focuses on developing newer and better therapeutic strategies, such as immunization against α-synuclein and gene therapy. Despite the challenges, understanding the mechanisms behind these disorders offers hope for future breakthroughs in their management and potential cure.

Neurodegenerative disorders are progressive conditions characterized by the irreversible loss of neurons in specific brain regions.

The primary therapeutic goal is alleviating symptoms and slowing down the neurodegenerative process, although a cure remains elusive.

Parkinsonism is a clinical syndrome characterized by bradykinesia, muscular rigidity, resting tremor, and impaired postural balance.

The most common form is idiopathic Parkinson's disease, involving dopaminergic neuron degeneration in the substantia nigra of the brain.

Notably, certain dopamine-blocking drugs like haloperidol and phenothiazines can also induce Parkinson-like symptoms, referred to as pseudoparkinsonism.

The pathophysiology of Parkinson's disease involves basal ganglia dysfunction and an imbalance between the direct and indirect neuronal pathways.

A key pathological feature of this disease is the presence of intracellular inclusions containing aggregated α-synuclein proteins, known as Lewy bodies, in the brain.

The primary treatment for parkinsonism relies on levodopa, a dopamine precursor that increases its levels in the brain.