London, Feb 14 (IANS): Long-term use of liraglutide -- a drug used to lower blood sugar levels in type 2 diabetes patients -- can have a deteriorating effect on insulin-producing cells, leading to an increase in blood sugar levels, warns a study.

Researchers at Karolinska Institutet in Sweden worked with humanised mice, generated by transplanting human insulin-producing cells into the mice to understand the effect of liraglutide therapy.

The findings revealed an initial improvement in the insulin-producing cells, followed by a gradual exhaustion, with reduced secretion of insulin as a response to glucose, the research showed.

Blood-sugar suppressors in the form of analogues of the incretin hormone GLP-1 are commonly used in the treatment of type 2 diabetes, since they stimulate the glucose response of the pancreatic beta cells to make them secrete more insulin, the researchers said.

To study the long-term effects of liraglutide therapy, which has never previously been assayed, researchers worked with humanised mice.

The mice were given daily doses of liraglutide for more than 250 days, during which time the researchers were able to monitor how the pancreatic beta cells were affected.

"We also need to take these results into account before prescribing blood-sugar suppressing GLP-1 analogues when planning long-term treatment regimens for patients," said Per-Olof Berggren, professor at Karolinska Institutet.

The findings will be detailed in the forthcoming issue in the journal, Cell Metabolism.