Diabetes drug may help with memory loss in dementia
"Diabetes drug significantly reverses memory loss in Alzheimer's patients," The Sun reports. What the headline failed to make clear is that the "patients" were in fact mice, which had been genetically engineered to develop Alzheimer's-like symptoms.
This new mouse study investigated whether a new drug developed for the treatment of diabetes, known as a triple receptor agonist (TA), could also be used to improve symptoms of Alzheimer's, such as memory loss.
Previous animal research has shown TA, which targets biologic pathways in the brain to regulate blood sugar levels, may also protect against Alzheimer's.
They found that mice given the modified version of TA appeared to have reduced memory loss, which was assessed by way of a water maze test.
Although an interesting study with promising results, this is just early-stage animal research. Further trials in the laboratory and then in humans would be needed to see whether this drug is a safe and effective treatment for Alzheimer's.
For now, maintaining a healthy and balanced lifestyle is recommended through healthy eating and exercise. This can help lower both the risk of type 2 diabetes and Alzheimer's disease.
Where did the story come from?
The study was carried out by a small team of researchers from Shanxi Medical University and Shaoyang University in China, and Lancaster University in England. It was funded by the Ministry of Human Resources and Social Security, a Shanxi Scholarship Council of China and a grant from the Alzheimer's Society UK.
The study was published in the peer-reviewed medical journal Brain Research. It is available on an open-access basis and is free to read online.
Generally, aside from its misleading headline, The Sun's coverage and the rest of the UK media's coverage was balanced. The reporting highlighted that the drug showed promise without getting too optimistic about the immediate use of it as a treatment for Alzheimer's.
What kind of research was this?
This was a mouse study that aimed to look into whether a new drug developed for the treatment of diabetes could also be used to improve symptoms of Alzheimer's disease.
The drug, known as a triple receptor agonist (TA), has similar properties to an established group of drugs used in the treatment of type 2 diabetes, called glucagon-like peptide-1 (GLP-1) analogues. These drugs are given by injection and mimic the effect of a group of hormones called "incretins" which help the body produce more insulin and less glucose.
Previous animal research has found that the same incretin hormones may have protective effects against Alzheimer's. However, the new drug has not yet been investigated in this capacity, so the researchers wanted to look into this further.
Animal studies like this one are useful early-stage research for finding out more about the potential effects of a drug, specifically regarding safety and effectiveness, before trialling in humans. But while mice have many genetic similarities to humans, they obviously aren't identical.
What did the research involve?
The researchers tested the effects of the new drug in a group of mice that were genetically bred to develop a neurological disease similar to human Alzheimer's disease.
The researchers had 3 groups of mice:
- "Alzheimer's mice" given TA mixed with saline
- "Alzheimer's mice" given saline only
- normal non-Alzheimer's mice given saline only that acted as the control group
The mice were given their respective treatments via a daily injection for 2 months.
Following treatment, the researchers analysed the mice for memory formation, inflammation, behavioural changes and damage to nerve cells. As part of this analysis, mice were required to take part in the Morris water maze test, which assesses learning and memory in animals. Findings were compared between the 3 groups.
What were the basic results?
The following findings were noted:
- treatment with TA was found to significantly reverse memory loss in the Alzheimer's mice in the water maze test
- tests showed that TA altered the levels of certain proteins, which may help preserve connection and communication between nerve cells in the brain
- there was also a reduction in the amount of beta-amyloid, inflammation and oxidative stress (damage that occurs at the cellular level) in the brain
How did the researchers interpret the results?
The researchers concluded that: "the results demonstrate for the first time that the novel GLP-1/GIP/Gcg receptor agonist has clear neuroprotective effects in the mouse model of Alzheimer’s disease."
Conclusion
This mouse study investigated whether a modified version of a drug developed for the treatment of diabetes could also be used to improve symptoms of Alzheimer's disease.
The researchers found suggestions that the mice given the drug had reduced memory loss in the water maze test, preserved brain function and less build-up of beta-amyloid plaques that are characteristic of Alzheimer's.
This is an interesting study with promising results. It furthers understanding of how drugs like GLP-1 analogues that target incretin hormones could also give protection against Alzheimer's. This could pave the way for potential use of drugs of this class to treat Alzheimer's in the future, as the researchers suggest.
However, the current study tests a new drug and data is limited to animal models.
With further testing and trials it remains uncertain whether it would be both safe and effective in humans. As Professor John Hardy (an independent expert not involved in the study) reminded The Independent: "several other drugs have shown positive results in mice models of Alzheimer's disease and then failed in human trials".
It's also worth noting that the new drug is still not available for the treatment of diabetes, the condition it was originally developed to treat.
While there is no guaranteed method of preventing Alzheimer's disease, you can help reduce your risk (as well as your risk of diabetes) through regular exercise and healthy eating.
