Drug might treat anxiety, weight- loss disorders, study shows
OTTAWA A study by Ottawa researchers has found a possible new treatment for anxiety and obesity disorders that enables the brain’s ability to “fix” itself by regulating the body’s natural production of cannabinoids.
Early results from the study suggest that by using Trodusquemine, a drug undergoing clinical trials for the treatment of weight- loss disorders and breast cancer, cannabinoids can be produced by the brain on its own that allow the patient to become calmer and more relaxed.
The study also suggests that the drug can be used to treat patients with anxiety and weight- loss disorders at the same time.
The study, published in the online neuroscience journal Neuron, has only been conducted on lab mice at this point, but the researchers are hoping that by publishing the results then interest can be generated in order to begin clinical trials.
The three- year- long study was originally an investigation into the effects of the gene LMO4 on brain development and regeneration, before the scientists noticed that mice who lacked this gene displayed anxiety- related behaviours and also became obese.
The mice were given small doses of Trodusquemine and after an hour the mice displayed less anx- ious behaviours that lasted for almost a week. The drug also seemed to have the effect of regulating the weight of the mice.
Dr. Hsiao- Huei Chen, who led the study, says the results are encouraging for doctors treating patients with these disorders. Chen is the associate professor of medicine at the University of Ottawa and a senior scientist at the Ottawa Hospital Research Institute.
“Anxiety and obesity are growing problems in society,” she said. “Not only have we found a new biological pathway that regulates these two conditions, but we also found that they may be amenable to treatment with the same drug.”
Trodusquemine t arg ets t he high levels of neural activity tak- ing place in specific regions of the brain by inhibiting the PTP1B enzyme, which regulates insulin levels and leptin levels and can indirectly regulate the amount of cannabinoids the body produces.
The drug was also found in a 2010 study to cause rapid weight loss and appetite suppression in mice.
“We gave them doses so low that we did not see significant weight loss, but with a larger dose it would have an effect,” she said. “However, this compound would only have an effect on fatter mice.”
As well, the drug only seemed to affect the mice exhibiting severe obesity or anxiety- related behaviours, and not mice displaying “normal” behaviours.
The drug blocks the PTP1B enzyme activity, so the brain creates its own cannabinoids and “fixes” itself, thereby moderating the patients’ anxiety.
Cannabinoids, along with cannabinoid- receptors, are part of the larger endocannabinoid system, which according to Vanderbilt University “regulates anxiety and the response to stress by dampening excitatory signals, meaning it slows down the firing of neurons in the brain. They are linked to physiological processes such as appetite, memory, and mood.
A recent study by Vanderbilt University discovered cannabinoid-receptors in a central part of the amygdala that regulates anxiety and the fight- or- flight response.