At the heart of it

Posted: 01st July 2019

The relationship between type 2 diabetes and heart disease is complex.
Dr Kim Loh, Head of the Diabetes and Metabolic Disease Laboratory in SVI’s Protein Chemistry and Metabolism Unit says that a unifying feature of these often-intertwined conditions is the involvement of an enzyme called AMP-activated protein kinase (AMPK).
AMPK, he says, plays a central role in controlling the balance between energy production and energy storage. When AMPK is active, energy production is increased and less energy is stored as fat.
Kim says, “New drugs that are in clinical trials now make the AMPK enzyme work harder. It is believed that turning the enzyme on in people with type 2 diabetes and heart disease will have beneficial effects.”
In 2018, Kim received support from the L.E.W. Carty Charitable Fund and subsequently from the National Health and Medical Research Council (NHMRC) to look at the role that AMPK plays in heart disease.
“Heart disease is primarily caused by atherosclerosis: a process in which fat, including cholesterol, accumulates on the inside of arteries. These fatty deposits can progress to block blood flow, causing heart attacks, stroke, or heart failure.”
One of the hallmarks of the early stages of atherosclerosis is the accumulation of specialised immune cells called macrophages in the blood vessels. Their job is to locate and engulf unwanted particles, such as cellular debris and foreign substances.
“It is thought that the macrophages arrive to deal with inflammation and the fat build up and then themselves contribute to the formation of the plaque and its consequences. There is some evidence that AMPK is involved in this process.”
Kim has developed a sophisticated suite of research tools to determine the role that AMPK plays. He has access to drugs that specifically turn the AMPK enzyme on and off, mice that are prone to the development of atherosclerosis, and others that carry mutations in specific parts of the AMPK enzyme.
Kim’s aim is to clarify the exact contribution that AMPK makes to the development of heart disease, in order to find new, more effective, ways of treating it.

For more information please see: Diabetes & metabolic disease