A breakthrough treatment for diabetic heart and vascular disease

Breakthrough research by the Heart Research Institute (HRI) has the capacity to drastically improve the life expectancy and outcomes of people with diabetes, which affects around 1.7 million Australians.

Diabetics are twice as likely to suffer heart disease or a stroke and tend to develop these complications at an earlier age. Around 50% of diabetics will die of heart disease or stroke as a result of their inability to make or repair blood vessels. 

By identifying a critical link between high blood sugar levels and the damage it causes arteries, HRI researchers have been able to directly target and reverse the gene, which hinders blood vessel growth in diabetics.

“High glucose levels directly stimulate a gene called Thioredoxin Interacting Protein (TXNIP), causing vascular damage in diabetics,” HRI scientist, Dr Louise Dunn said.

“By directly targeting TXNIP and preventing the stimulation caused by glucose, we were able to create a striking reversal of the highly damaging effects of hyperglycaemia and diabetes and increase the growth of blood vessels.

To prevent TXNIP induction by diabetes, the study used a technology called small interfering RNA (siRNA) that works by targeted interruption of TXNIP protein expression. The siRNA dramatically reduced TXNIP levels to rescue impaired vascular cell function and new blood vessel growth in diabetic mice to levels seen in healthy non-diabetic controls.

“Diabetics have poor ability to heal and recover and many lose limbs or have multiple and often fatal heart attacks and strokes,” Dr Dunn said.

“These findings lead us to believe that we will eventually have a new class of drugs to treat diabetes by targeting TXNIP which has the potential to prevent diabetic heart disease as well as increasing a diabetic patient’s capacity to recover and significantly improving their quality of life.

“Our next step will be to develop and test a drug that specifically targets TXNIP.”

Dr Dunn’s ground-breaking work was completed in late 2009 and was ‘top rated’ at the 2009 American Heart Association’s Scientific Sessions, the world’s premier cardiovascular conference.