Anti-Parkinsonian agents have anti-amyloidogenic activity for Alzheimer's beta-amyloid fibrils in vitro
Ono K, Hasegawa K, Naiki H, Yamada M.
Department of Neurology and Neurobiology of Aging,
Kanazawa University Graduate School of Medical Science, Kanazawa, Japan.
Neurochem Int. 2005 Dec 9;
ABSTRACTInhibition of the accumulation of amyloid beta-peptide (Abeta) and the formation of beta-amyloid fibrils (fAbeta) from Abeta, as well as the destabilization of preformed fAbeta in the central nervous system would be attractive therapeutic targets for the treatment of Alzheimer's disease (AD). Many studies have demonstrated that oxidative damage plays a central role in AD pathogenesis, as well as Parkinson disease (PD). Among the antioxidant strategies proposed, increasing evidence points to the possibility of achieving neuroprotection by dopamine agonists, as well as monoamine oxidase B (MAO-B) inhibitors. Actually, the beneficial effect of selegiline, a MAO-B inhibitor, in AD has been noted in several clinical studies. On the reverse, antimuscarinic agents have been reported to accelerate beta-amyloidosis and senile plaque formation in PD. Using fluorescence spectroscopic analysis with thioflavin T and electron microscopic studies, we examined the effects of anti-Parkinsonian agents, dopamine, levodopa, pergolide, bromocriptine, selegiline, and trihexyphenidyl on the formation, extension, and destabilization of fAbeta(1-40) and fAbeta(1-42) at pH 7.5 at 37 degrees C in vitro. The anti-Parkinsonian agents other than trihexyphenidyl dose-dependently inhibited fAbeta formation from Abeta(1-40) and Abeta(1-42), as well as their extension. Moreover, these agents dose-dependently destabilized preformed fAbetas. The overall activity of the molecules examined was in the order of: dopamine>selegiline>levodopa=pergolide>bromocriptine. Although the exact mechanism of the anti-amyloidogenic activity of these agents is unclear, these and other structurally related compounds could be key molecules for the development of therapeutics for AD and other conformational diseases.
Selegiline plus phenylalanine
Selegiline and life-expectancy
Selegiline for longer-lived flies
Selegiline as an immunostimulant
Selegiline for cocaine-dependence
Selegiline and Parkinson's disease
Selegiline, NO and Alzheimer's disease
Antidepressant/dopamine D1 receptors
Transdermal selegiline as an antidepressant
Somerset's new transdermal selegiline patch
and further reading
The Abolitionist Project
The Hedonistic Imperative
The Reproductive Revolution
Critique of Huxley's Brave New World
The Good Drug Guide
The Responsible Parent's Guide
To Healthy Mood Boosters For All The Family