Parkinson's disease: a short story of 200 years.

After Alzheimer's disease, Parkinson's disease (PD) is the second most prevalent and incidental neurodegenerative disorder, affecting more than 2% of the population older than 65 years old. Since it was first described 200 years ago by Dr James Parkinson, great steps have been made in the understanding of the pathology. However, the cause(s) that initiates and perpetuates the neurodegenerative process is (are) still not clear. Thus, early diagnosis is not available, nor are there efficient therapies that can stop neurodegeneration. PD clinical features are defined by motor (like bradykinesia, resting tremor, gait impairment) and non-motor symptoms (like constipation, apathy, fathigue, olfactory dysfunction, depression and cognitive decline) that get more severe as the disease advances. Neuropathological hallmarks comprise selective loss of dopaminergic neurons in the Substantia Nigra pars compacta (SNpc) and Lewy bodies (LB) in different nuclei of the nervous system. Numerous studies have shown that these pathological features are aggravated by the confluence of other contributing factors, such as a genetic component, exposure to environmental toxins, mitochondrial dysfunction, increase of oxidative stress, calcium imbalance and chronic neuroinflammation, among others. Here, we provide a summary of the actual state of PD's pathology, the most studied molecular mechanisms, classic and novel therapeutic strategies and diagnosis methods, especially highlighting recent advances in these 200 years.