Biochemical and Molecular Pathogenetic Mechanisms behind Causation of Parkinson’s Disease

Parkinson’s disease (PD) is an age-related neurodegenerative disorder that affects approximately 1
million persons in the United States. It is characterized by resting tremor, rigidity, bradykinesia, gait
disturbance and postural instability. Its pathological features include degeneration of dopaminergic
neurons in the substantia nigra pars compacta coupled with intracytoplasmic inclusions known as
Lewy bodies. Neurodegeneration and Lewy bodies can also be found in locus ceruleus, nucleus
basalis, hypothalamus, cerebral cortex, cranial nerve motor nuclei, and central & peripheral
components of autonomic nervous system. The appearance of Lewy-body-like inclusions in nigrostriatal
terminals might be followed by retrograde degeneration, further accumulation of aggregated
proteins in nigral cell bodies and, finally, reactive gliosis and cell death. In familial forms of Parkinson’s
disease, linked to mutations in α-synuclein, it is proposed that a loss of normal function of this protein,
as well as a toxic effect of altered forms of the mutant protein, promote the accumulation of dopamine
in cytoplasm. This would result in oxidative stress, leading to the onset of neurodegenerative changes
mentioned above. Finally, we review evidence for a role of α-synuclein in synaptic vesicle recycling&
suggest that impaired function of this protein might lead to accumulation of dopamine in cytoplasm.
This could be the final deleterious event that triggers the death of nigral dopaminergic neurons in PD.
In addition to prevailing pharmacologic therapies and surgical procedures,Yoga can be one of the
most beneficial complementary therapies for PD patients, which canact at molecular level to reduce
oxidative stress, improve neuro-cognition, boost their mood, enhance sensory-motor performance,
increase dopamine & serotonin secretion and reduce cortisol secretion, thereby collectively enhancing
quality of life of PD patients & their care-takers.