INSIGHT Research #2: Professor Robyn Guymer talking cutting-edge science with Dr Hitesh Peshavariya
In the second episode of Insight Research, Professor Robyn Guymer talks with Principal Investigator Dr Hitesh Peshavariya, Head, Oxidant Signalling.
Dr Peshavariya is a biochemist in the field of oxidative stress and redox signalling pathways. His research interest includes ocular fibrosis and age-related macular degeneration (AMD).
One of the important questions Dr Peshavariya and his team is looking to solve is how oxidative stress, caused by oxygen-free radicals, impacts on eye disease.
“The over-supply of oxygen-free radicals tends to occur from diseased cells that are constantly exposed to UV light, radiation, trauma, chemicals, toxins or microbes, which trigger oxidative stress in the eye,” says Dr Peshavariya.
“Antioxidant vitamin tablets are not as effective as they should be as they are only present for a short period and do not block the source of the oxidant-producing enzymes,” he adds.
Dr Peshavariya’s approach is to probe the function of a naturally occurring enzyme in the body, NADPH oxidase, which overproduces oxygen-free radicals when diseased. The goal is to block the production of free radicals and reduce oxidative stress.
Dr Peshavariya is testing his hypothesis using patient cells grown from cells harvested during glaucoma surgery as well as in preclinical models. The results so far, he says, are encouraging.
“We have shown if you can block the enzyme involved in the formation of scar tissue then you can block scars forming in the eye,” he says.
AMD shares many common risk factors with cardiovascular diseases, including inflammation and dietary fat intake. High density lipoprotein (HDL), the ‘good cholesterol’ removes excess fat and inhibits inflammation in cardiovascular diseases. Inflammation is known to modify HDL and make it defective.
Dr Peshavariya and his collaborator Prof Guymer found that defective HDL increased in a number of AMD patients and its beneficial functions may be impaired in AMD.
Infusion of functional HDL reversed earlier changes of AMD in the pre-clinical model.