A common rheumatoid arthritis treatment may offer an effective new therapy for lowering the blood glucose levels of patients with type 2 diabetes, a study has found.
The anti-inflammatory drug Leflunomide lowered blood glucose levels and reversed insulin resistance in mouse models of type 2 diabetes, which suggests that this therapy could be re-purposed as an effective antidiabetic treatment, researchers said.
They said it would be particularly suitable for patients with both diabetes and rheumatoid arthritis.
Rheumatoid arthritis is a chronic condition that causes pain, swelling and stiffness in the joints and affects around 1% of the worldwide population.
Leflunomide has long been approved to treat the condition and previous clinical studies have noted that patients taking the drug tended to have lower blood glucose levels and that obese patients lost weight.
Type 2 diabetes is a lifelong condition that causes a person’s blood sugar level to become too high and is linked to a poor diet, obesity and an inactive lifestyle. There are almost 3.7 million people diagnosed with diabetes in the UK.
In addition to controlling lifestyle factors, many patients require drug therapy to correct their blood glucose levels.
Researchers at Yangzhou University in China said that although previous findings have indicated that Leflunomide may help treat type 2 diabetes, the mechanisms behind these observations had never been fully investigated, nor its effectiveness tested.
Their study, which is published in the Journal of Endocrinology, investigated its effects on the blood sugar levels of two different type 2 diabetes mouse models.
In both models Leflunomide not only normalised blood glucose levels, but also caused cells to start responding to insulin again.
Professor Xiulong Xu, who led the study, said: “We studied how Leflunomide works at a molecular level, and found that it targets a protein involved in desensitising the insulin receptor, which is responsible for instructing the cells to start absorbing sugar from the bloodstream.”
However the drug also acted on other molecular targets in the body, suggesting that more studies are needed to confirm that the antidiabetic effects observed are solely caused by Leflunomide’s effect on the insulin receptor.
“We know some inflammatory factors can also desensitise the insulin receptor, and Leflunomide is an anti-inflammatory, so it may be that it controls blood sugar partly by its anti-inflammatory effect,” Professor Xu added.