Dopamine is a neurotransmitter that promotes feelings of pleasure and reward, supports memory, attention, and more.¹

As we age, increased activity of an enzyme called monoamine oxidase B (MAO-B) degrades dopamine, causing levels to fall.²

Lower dopamine levels can contribute to reduced motivation and decreased enthusiasm for things that would excite most people.

A solution is to ingest compounds that inhibit the MAO-B enzyme.

Scientists have found that components of phellodendron tree bark accomplish this in lab studies^3,4 and have neuroprotective effects in animals.^5-7

Preclinical research also shows that a specific form of vitamin B12 may protect neurons and help prevent a decline in dopamine levels.⁸

These compounds may help maintain motivation and feelings of pleasure, while reducing risk for neurodegenerative illnesses.

What is Dopamine?

Dopamine is often referred to as the “feel-good hormone” due to its role in regulating mood.¹

The brain releases dopamine during pleasurable activities. Low dopamine levels are associated with depression and a lack of motivation and pleasure.⁹

But the brain uses dopamine for more than mood elevation.

This neurotransmitter also influences movement, learning, cognition, and memory.¹⁰

Dopamine enables youthful cognitive performance and body coordination.^11,12

Dopamine depletion plays a role in certain neuro-degenerative diseases, while increasing dopamine has been shown to prolong lifespan in animals.^1,13,14

In a region of the brain that plays a role in cognitive and motor function, levels of dopamine decline by about 13% each decade after age 45.¹⁵

This decline coincides with an increase in the brain levels of monoamine oxidase B (MAO-B), an enzyme that degrades neurotransmitters such as dopamine.²

Low dopamine levels are associated with depression, lack of motivation, and pleasure.⁹ These mood and motivational changes also may be seen with normal aging in some people.

Rising MAO-B levels pose even more of a threat.

MAO-B activity is higher in dementia patients than in non-impaired individuals the same age,¹⁶ suggesting a role in neurodegeneration.

One reason may be that increased MAO-B activity results in formation of potentially damaging by-products^2,17,18 that can contribute to neurodegenerative diseases such as Parkinson’ and Alzheimer’s Disease.

Doctors frequently prescribe MAO-B inhibitors such as deprenyl (also called selegiline) to stop MAO-B degradation of dopamine in patients with Parkinson’s disease.¹⁹

Inhibiting MAO-B activity helps decrease the breakdown of dopamine and the potential harm that can be done by too much enzyme activity. This helps protect our aging brains.

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