Neurodegenerative and Neuropsychiatric Disorders: Present Clinical Drug Research and Future Perspectives

Neurodegenerative disorders are elucidated as genetic and intermittent diseases which are described by progressive nervous system dysfunctions. These disorders have often being correlated with the degeneration of nerve cells. Most prevalent diseases are Alzheimer’s disease (AD) and related dementias, Encephalitis, Epilepsy, Parkinson’s disease (PD), Multiple sclerosis, Amyotrophic lateral sclerosis, Huntington’s disease, Schizophrenia and Prion diseases. All neurodegenerative diseases are disastrous and impact social as well as economic wellbeing. However, the majority of neuropatients are affected by AD, PD and together they cost the health care system almost billions of dollars per year. Besides, Schizophrenia is a severe mystery with no effective medical treatment. Therefore, AD, PD and Schizophrenia have been discussed at length in the present chapter. The AD is characterized by two neuropathological lesions, senile plaques composed of Aβ peptide and neurofibrillary tangles (NFTs) containing aggregated hyperphosphorylated Tau protein. The importance of Tau dysfunction in neurodegeneration is further supported by the enrichment of Tau genetic variants in cohorts of patients suffering from frontotemporal lobar degeneration disorder (FTLD). Memory loss, trouble sleeping, language problems, thinking and reasoning skills are the most common symptoms of AD. The PD is the second most common neurodegenerative disease which involves the breakdown and death of neurons in the brain. The core symptoms of PD are tremor, rigidity, bradykinesia and balance difficulties. Schizophrenia is a genetic brain disorder. Delusions, hallucinations, social withdrawal and disturbed thinking are some of its key symptoms. The genes causing these neurodegenerative disorders have been identified for more than two decades. Key researchers in this field have revealed numerous events at molecular and cellular levels, thus playing an important role in these fatal disorders. Many associated pathological events and therapeutic correlations are not clearly understood and therefore, there is no known cure for these chronic and progressive neurological disorders. This chapter aims to address AD, PD and Schizophrenia researches that may divulge novel mechanisms and targets for therapeutic intervention. It collates the significant findings of various experts in studying these degenerative diseases and stimulates novel perception to the campaign against devastating neurodegenerative diseases.