Associate Professor Alexander Tups and Associate Professor Rajesh Katare
Investigating how to prevent heart disease and treat diabetes so people do not lose limbs are the focus of two School of Biomedical Sciences academics who received HRC Explorer Grants.
Associate Professor Rajesh Katare is researching whether saliva tests can pinpoint the risk of developing heart disease and Associate Professor Alexander Tups how the hormone leptin controls both body weight and glucose levels, to help tissue regenerate and prevent both limb loss and severe heart disease.
Both academics are elated to be among six University of Otago recipients and to each receive $150,000, which they need to continue their health research.
Associate Professor Katare also says it is great to be “recognised by the HRC as having the potential to improve health outcomes in New Zealand.”
Heart disease and molecules
He plans to test a small level of molecules in the saliva because previous studies have shown that these molecules acting in an irregular way (dysregulation) plays a crucial role in the development of heart disease.
This research will test salivary samples from a variety of diverse participants from across New Zealand to determine if the risk of heart disease can be identified using saliva.
Associate Professor Katare's interest in these molecules began in 2012 when, despite the remarkable advances in treatments, he realised the number of people diagnosed with heart disease kept rising.
“Heart disease is the major cause of mortality across the globe and the best way to reduce this is to prevent the development of disease at much earlier stage,” he says.
“However, as of now, it is impossible to identify the disease in its early stages which is why our research is so important because, if we are successful, we will be able to identify those at risk simply and efficiently, having a significant impact on the health outcomes.”
A tissue repair hormone for diabetes
Associate Professor Tups' vision for improved health services involves focussing on how the hormone leptin – produced by fat cells in the human body – works to control body weight and glucose levels.
By studying this hormone's function in zebrafish, he made the novel discovery this hormone facilitates tissue repair in that species.
“It is well known that individuals with obesity or type 2 diabetes have severely impaired tissue repair and wound healing, but the underlying mechanisms are largely unknown,” Associate Professor Tups says.
“Based on the zebrafish finding, we believe that leptin is the missing link in the puzzle of appendage regeneration research (replacing lost or damaged fingers, toes, limbs etc).”
So while impaired tissue regeneration is often thought to be a complication of type 2 diabetes, he now believes it is caused by losing leptin function.
Leptin regulates the long-term balance between hunger and energy use – preventing people feeling hungry when they do not need food, to help maintain their weight over time – so if leptin stops functioning as people become obese, that could directly explain the onset of type 2 diabetes as well as impaired tissue repair and wound healing.
If Associate Professor Tups' hypothesis proves to be correct, then one mechanism could treat both type 2 diabetes and wound healing.
“Type 2 diabetes and prediabetes affects the lives of many New Zealanders, particularly Māori and Pacific Peoples, with one of the major complications of the disease being impairments in tissue repair that can lead to limb amputations or severe heart disease,” he says.
“By studying the mechanism of how this is caused we can then develop treatments that target this specific mechanism, potentially bringing relief to the many people affected by this disease.”