Catecholaldehyde hypothesis

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Chemical structure of DOPAL. Dihydroxyphenylacetaldehyde.png
Chemical structure of DOPAL.

The catecholaldehyde hypothesis is a scientific theory positing that neurotoxic aldehyde metabolites of the catecholamine neurotransmitters dopamine and norepinephrine are responsible for neurodegenerative diseases involving loss of catecholaminergic neurons, for instance Parkinson's disease. [1] [2] The specific metabolites thought to be involved include 3,4-dihydroxyphenylacetaldehyde (DOPAL) and 3,4-dihydroxyphenylglycolaldehyde (DOPEGAL), which are formed from dopamine and norepinephrine by monoamine oxidase, respectively. [1] [2] These metabolites are subsequently inactivated and detoxified by aldehyde dehydrogenase (ALDH). [1] [2] DOPAL and DOPEGAL are monoaminergic neurotoxins in preclinical models and inhibition of and polymorphisms in ALDH are associated with Parkinson's disease. [1] [2] [3] [4] The catecholaldehyde hypothesis additionally posits that DOPAL oligomerizes with α-synuclein resulting in accumulation of oligomerized α-synuclein (i.e., synucleinopathy) and that this contributes to cytotoxicity. [1] [2] [5] [3]

See also

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References

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