Appetite suppressant can also control anxiety: study

Photo: Remi Yuan

A study by University of Ottawa researchers at the Ottawa Hospital Research Institute has found a link between obesity and anxiety—and they may have also found a drug that helps with both.

Dr. Hsiao-Huei Chen, an associate professor in the department of medicine at the University of Ottawa, and her colleagues made the discovery while conducting tests on mice in their lab.

The project

Over the last three years of observation, one of Dr. Chen’s students, Zhaohong Qin, discovered that some of the mice were behaving abnormally and later becoming obese and diabetic. The researchers determined they were feeling anxious.

“These mice had late-onset obesity and diabetes, and an early onset of anxiety, so we asked the simple question of if the cause for this similar pathway is shared between both diseases,” Dr. Chen said.

She and her team had started using a drug that is an inhibitor for the enzyme PTP1B, called Trodusquemine, on the obese mice. After learning that the drug was able to help regulate appetite in these mice, they were curious to see if it could help with anxiety as well.

The result

The researchers found that the enzyme’s activity can cause a resistance to insulin, which resulted in obesity and Type 2 diabetes. This activity can also affect the brain’s production of its own cannabis-like chemical, which regulates neuron activity. Drugs that are commonly prescribed for anxiety, such as Xanax, are called benzodiazepines, and they help shut down the overactive neuron activity in the brain.

Dr. Chen said that “when you take this drug orally, it will reach every part of your brain.” This presents a problem because it not only calms the necessary activity, but can also affect your memory and concentration. This could be a challenge for students who are trying to cope with anxiety, but don’t want to see their grades suffer as a side effect.

Trodusquemine, the subject of the study, “lets the brain fix itself,” said Dr. Chen, because it focuses its effects on one area of the brain. Dr. Chen said she believes this makes it “quite safe,” and hopes these studies will help Trodusquemine become the drug of choice for patients with anxiety.

What’s next?

Mental health issues, including anxiety, have become a pressing issue on university campuses in recent years. The Canadian Alliance of Students Associations released a report last summer calling for better mental health services on Canadian campuses.

The drug is currently in clinical trials for appetite control, weight loss, and its possible effect on breast cancer. With the recently discovered link between obesity and anxiety, Dr. Chen said she hopes its effects on anxiety will be tested separately soon.