Cat’s Claw (Uncaria rhynchophylla) as a Monoamine Oxidase Inhibitor

weight lossMonoamines are a group of chemical neurotransmitters in the brain that include serotonin, noradrenaline and dopamine. Monoamine oxidase (MAO) is an enzyme that is responsible for the breakdown of monoamines in the brain and the peripheral nervous system. Monoamine oxidases exists in two forms, MAO A and MAO B, and these have slightly different but overlapping affinities for various monoamines. Ageing causes an increase in MAO activity which might explain the increased risk of depression and anxiety with age. Some herbs are excellent MAO inhibitors. For example, extracts of the hooks of the Uncaria rhynchophylla (cat’s claw) plant has been shown to inhibit MAO B. Cat’s claw hooks contain epicatechin and catechin, and these flavonoids may be responsible at least in part for the inhibitory effect of MAO B. By inhibiting MAO B. Green tea is also an excellent source of epicatechin and catechin, which may explain the mood elevating effects of green tea.

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Monoamine oxidase B is tasked mainly with metabolising dopamine. Whereas Monoamine oxidase A metabolises dopamine, serotonin and noradrenaline. Inhibition of monoamine oxidase B therefore might be expected to raise levels of dopamine in certain parts of the brain. Image shows the hooks of the cat’s claw vine which contain the flavonoids epicatechin and catechin. Image from: By keisotyo – 自分で撮影, CC BY-SA 4.0, https:// w/ index.php?curid=9466954.

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Hou, W. C., Lin, R. D., Chen, C. T. and Lee, M. H. 2005. Monoamine oxidase B (MAO-B) inhibition by active principles from Uncaria rhynchophylla. Journal of Ethnopharmacology. 100(1-2): 216-220

About Robert Barrington

Robert Barrington is a writer, nutritionist, lecturer and philosopher.
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