Researchers find benefits in how metformin works that could improve blood sugar levels.
Researchers at Newcastle University have found that the way a drug regularly prescribed for people with type 2 diabetes works could have health benefits for people with type 1 diabetes.
Metformin is an inexpensive treatment and is often prescribed for people with type 2 diabetes to help lower blood sugar levels as it reduced glucose production in the liver. The drug is not regularly given to people with type 1 diabetes.
However, a DRWF-funded study has found that the treatment could also prevent heart disease in patients with type 1 diabetes – and could lead to the development of new treatments.
A clinical trial found that metformin could promote a patient's ability to repair their own damaged blood vessels by decreasing the presence of microRNAs (miRs) which increases the growth of blood vessels - in addition to improving glucose levels.
These microRNAs are messenger molecules which regulate different genes in different cells.
The results of the study were recently published in the International Journal of Molecular Sciences.
Dr Jolanta Weaver, Senior Lecturer in Diabetes Medicine at Newcastle University and Honorary Consultant Diabetologist at Queen Elizabeth Hospital, Gateshead, led the clinical trial at the Gateshead hospital and study lead author said: “This is an exciting development as understanding this underlying mechanism opens up the possibility of new forms of treatment which will lower the chances of patients with type 1 diabetes developing heart disease.
“As the outcomes of heart disease are worse in people with diabetes compared to people who don’t have the condition, there is a need to identify additional treatment options.
“Our previous study showed that the vascular stem cells were improved by metformin so this was the first example of how metformin improved heart disease as well as lowering glucose levels.
“Now we know that the drug metformin was able to do this by lowering the presence of microRNAs.”
A previous study had already shown the potential of metformin to slow the development or delay heart disease. However, this new study was the first time that the potential of miRs in preventing heart disease had been identified.
The MERIT study was the first to test the heart protective effects of metformin in people with type 1 diabetes. For the study 23 people, aged between 19 and 65, with type 1 diabetes who were free of cardiovascular disease, were treated with metformin for 8 weeks.
Patients in the treatment group were matched with a standard group of nine people with type 1 diabetes taking standard insulin. There was a further 23 participants in the "healthy" control group without diabetes.
At the start of the study, several anti-angiogenic microRNAs were detected to be higher in people with type 1 diabetes compared to the control group. However, metformin treatment successfully reduced the levels of microRNAs.
Moreover, as the levels of microRNAs went down, there was a corresponding decrease in the amount of circulating endothelial cells, which indicates an improvement in vascular repair.
Dr Weaver added: “These results confirm that as well as improving a patient’s blood sugar control, metformin is working to protect the heart.”
The team will now be working to further the work with the goal of developing new treatments based on regulating the levels of microRNAs.
The study was funded by DRWF and the Diabetes Research Fund at the Queen Elizabeth Hospital, Gateshead.
Alex Laws took part in the study
Alex Laws was part of the Newcastle University clinical trial and is delighted with the progress in the study.
The 33-year-old, of Gateshead, was diagnosed with type 1 diabetes when she was seven and has good control of her condition. She was enrolled on the clinical trial in the summer of 2013.
Alex said: “I previously worked in medical research so I know how important studies like this can be in helping people, like me, with type 1 diabetes.
“Type 1 diabetes can lead to a number of complications, especially in the long-term, so it's important as much as possible is done to limit serious problems.
“Heart disease is a concern for people with type 1 diabetes so understanding how treatments can help and improve the condition for patients is a good thing.”
Dr Eleanor Kennedy, Research Manager at DRWF, said the study was a good example of how a small amount of Pump Priming money can impact research in diabetes.
Dr Kennedy said: “The DRWF’s Pump Priming funding scheme allows researchers to apply for relatively small amounts of money. The programme is designed to help obtain pilot data that could, if positive, lead to a much bigger study and this is a great example of how this works.
“By funding perhaps some equipment or some salary costs, DRWF can help to leverage in more substantial funding allowing bigger piece of important research to be conducted. Dr Weaver’s study on the uses of metformin in type 1 diabetes is an important finding that may open new avenues in the growing field of microRNA research.”