Dopamine may improve memory in Alzheimer’s patients, study suggests: What you need to know

The main line

Researchers have found that increasing dopamine production in mice with Alzheimer’s disease improves their memory, a process they hope can be replicated in humans, although more testing is needed for a better human alternative.

The woman hugging her older mother.

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Key facts

A research team from Japan’s RIKEN Center for Brain Science tested the new treatment method, increasing dopamine production in the brains of Alzheimer’s mice in hopes of increasing levels of an enzyme called neprilysin.

Previous research has shown that neprilysin can reduce the production of protein fragments called beta-amyloid, which causes plaque to form around brain neurons – one of the earliest indicators of Alzheimer’s disease – and the research team previously found that the neurotransmitter dopamine increases neprilysin levels.

Scientists were able to continuously activate neurons in the brains of mice that produce dopamine, and after eight weeks the mice had significantly fewer plaques in their brains, according to a new study published Tuesday in Science Signaling.

Next, levodopa – a Parkinson’s drug used as a dopamine replacement – was given to some of the mice because, although the drug has severe side effects, increasing dopamine production in humans with a drug is a more feasible treatment method than genetic manipulation of growth as. researchers did with mice.

The drug was given for three months and led to an increase in neprilysin and a subsequent decrease in beta-amyloid, and mice given this treatment performed better on memory tests than the placebo group that was not treated with the drug.

What side effects does Levodopa have?

Researchers believe that levodopa – also known as L-DOPA – is a good starting point to begin research into human treatment of increased dopamine production in Alzheimer’s patients, but it may not be the best option in the long term because has “serious side effects. In some Parkinson’s patients. Some of the more common side effects include dizziness, nausea, confusion, hallucinations, psychosis, low blood pressure, agitation and delusions, according to StatPearls research. Long-term use can lead to in complications such as irreversible changes in motor function, which affect approximately 50% of patients who take the drug for five to 10 years. Because of these side effects, “our next step is to investigate how dopamine regulates neprilysin in the brain , which should provide a new preventive approach that can be started at the preclinical stage of Alzheimer’s disease,” Dr. Watamura Naoto, first author of the study and researcher with the RIKEN Center for Brain Science, said in a statement.

What is dopamine?

Dopamine—also known as the “feel good neurotransmitter”—is a hormone and a type of neurotransmitter in the brain that is used by the nervous system to send messages to nerves, according to the Cleveland Clinic. It plays an important role in the brain’s reward system because it is released from the brain when a person does something that is pleasurable. This dopamine rush causes a person to seek more of that feeling, which can lead to behaviors like drug and alcohol addiction and overeating, according to the Cleveland Clinic. Research has shown that the hormone can play a big role in dementia, because low levels of dopamine can indicate early signs of Alzheimer’s disease and other forms of dementia.

Big number

6.7 million. That’s how many Americans age 65 and older will have Alzheimer’s in 2023, according to the Alzheimer’s Association. About one in nine people age 65 and older have Alzheimer’s.

tangential

Erectile dysfunction drugs like Viagra may also be key Alzheimer’s treatments, according to a Neurology study published in February. The researchers found that participants who were given erectile dysfunction drugs were 18% less likely to develop Alzheimer’s than their counterparts who were not. The types of drugs used in the study are called phosphodiesterase type-5 inhibitors, and researchers believe that PDE5I may reduce the risk of Alzheimer’s because some forms of the drug can improve brain health by increasing blood flow to the brain and reducing the amount of neurons. of energy. consumed in the brain.