Studies on homocysteine and dehydroepiandrosterone sulphate plasma levels in alzheimer’s disease patients and in Parkinson’s disease patients

Abstract

Homocysteine (HC) and dehydroepiandrosterone sulphate (DHEAS) plasma levels have been evaluated in groups of male and female patients with Parkinson's disease (PD) and in a group of female patients with Alzheimer's disease (AD) and compared with the corresponding plasma levels observed in a group of age-matched subjects. It has been confirmed that HC plasma levels are enhanced in both PD and AD patients. As far as the DHEAS plasma levels are concerned no changes have been observed in PD patients while a marked decrease has been observed in AD patients. These results support the view that while the pro-oxidant effects of HC and its agonist action at NMDA receptors can play a role in both neurodegenerative diseases, the role of DHEAS is more complex and may be an important factor only in certain neurodegenerative diseases. Thus, according to the present study DHEAS is likely to be involved in AD but not in PD.

Role of Cooperativity in Protein Folding and Protein Mosaic Assemblage Relevance for Protein Conformational Diseases

“…Such a view has great clinical relevance and may be a new target for therapeutic intervention in AD. In fact, it should be mentioned that high plasma levels of Hcy have been demonstrated as a risk factor for Alzheimer's disease [56] and Hcy plasma levels steadily increase with age reaching high values in Alzheimer and Parkinson patients [57]. Thus, our own findings and data in the literature support the hypothesis that Hcy by interacting with A causes a conformational change in the monomer favouring the -sheet conformation.…”

Homocysteine and asymmetric dimethylarginine concentrations in the plasma of Alzheimer’s disease patients with varying degrees of dementia

“…The proteins most probably induce oxydative stress [15,16]. As indicated in reports on the subject [17], also elevated levels of homocysteine (Hcy), in degenerative diseases, might be responsible for increased oxydative stress. It has been also suggested that the pro-oxidative activity of Hcy in AD most probably involves direct interaction of Hcy with NMDA receptors.…”

Neuroprotection and mechanisms of atractylenolide III in preventing learning and memory impairment induced by chronic high-dose homocysteine administration in rats

“…Clinical investigations have shown that elevated Hcy plasma levels has been identified in patients with neurodegenerative diseases such as Alzheimer's disease (AD), Parkinson's disease (PD) and multiple sclerosis (MS) (Clarke et al, 1998;Kuhn et al, 1998;Genedani et al, 2004;Agnati et al, 2005;Russo et al, 2008), and that there was a tight correlation between the elevated Hcy plasma levels and cognitive impairment in the elderly, AD patients and MS patients by the retrospective and prospective studies (Prins et al, 2002;Seshadri et al, 2002;Russo et al, 2008). Elevated Hcy plasma levels have been recognized as an important risk factor for cognitive dysfunction (Miller, 2003).…”