Etiology of Neurodegenerative Diseases

What is the correct statement about the etiology of neurodegenerative diseases ... 

Besides the role of EAA in physiological actions, an excitotoxic etiology of neurodegenerative diseases has been proposed in the last few years (see also the chapter by Zorumski and Olney in this volume). A lot of investigations show a noxious effect of EAA, which is mediated by Ca + influx into the cytoplasm (Monaghan et al. 1989 Mayer and Miller, 1991). Endogenous and envi-... 

Alterations in the ubiquitin-proteasome pathway have been connected to several neurodegenerative diseases (Table 9). In some instances, mutations in specific genes have been linked to the etiology of the disease. Although the perturbations in ubiquitin-proteasome-mediated proteolysis lead to pleiotropic effects on neurons including cell death or degeneration, one of the early effects is believed to be synaptic malfunction. 

Neurodegenerative processes can involve diverse areas of the CNS. The initial etiology of such disturbances is mostly unknown. Nevertheless, we can distinguish between an idiopathic and a symptomatic form of neurodegenerative disease. A close examination of the latter enables one to make valuable conclusions about the nature of the former. Thus, we can amplify our knowledge by examining function, structure and biochemistry of the CNS in symptomatic cases and by looking for comparable alterations in idiopathic forms. 

Youdim MBH, Amit T, Bar-Am O, Weinreb O, Yogev-Falach M. Implications of co-morbidity for etiology and treatment of neurodegenerative diseases with multifunctional neuroprotective-neurorescue drugs Ladostigil. Neurotox. Res. 2006 10(3,4) 181-192. 

Despite differences in disease etiology and cellular properties of affected neurons in various forms of neurodegenerative disorders, loss of acetylation homeostasis appears to represent a critical and decisive mechanism commonly underlying... 

The etiologies of the neurodegenerative diseases are still largely unknown but, especially for AD and PD, postmortem studies have shown clear links between the disease and a deficiency of neurotransmitters in some parts of the brain. Thus, in PD there is a chronic shortage of dopamine... 

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