Gemma Moir-Mayer addressed her topic “Iron and Anaemia: A Careful Balancing Act Between Health and Disease” with sufficient detail and explanation for the average Rotarian to grasp.
Anaemia is a reduction in the blood's oxygen carrying capacity. It affects up to 800 million women and children worldwide, with the majority of this burden falling in low income countries. However, anaemia also affects 4.5 per cent of Australians. Iron deficiency is one of the most common causes of anaemia.
At Pasricha Laboratory they seek to discover new therapies to prevent and treat anaemia by making fundamental discoveries into how the body regulates its iron stores. The Lab also undertakes field studies in sub-Saharan Africa and South Asia to test new solutions and influence policy to address anaemia in babies and pregnant mothers.
Gemma explained the process of erythropoiesis, how red blood cells are created - 2 to 3 million cells per second, and they only have a life of 120 days. She detailed how iron is carried in the complex molecule of haemoglobin, which is essential in carrying oxygen from the lungs to the body. We need 24 mgm of iron per day, and 95% of this is recycled when the red blood cells age and break down. The body absorbs iron in the duodenum, and is exported by ferroportin, governed by the hormone Hepcidin. Iron is also excreted by bleeding.
Gemma compared the conditions of iron deficiency and iron overload, and she described how the body tries to maintain a balance.
In her work as a molecular geneticist at Pasricha Laboratory she is studying Erythroferrone, which is a protein hormone encoded in humans by the ERFE gene. Erythroferrone is produced by erythroblasts, inhibits the production of hepcidin in the liver, and so increases the amount of iron available for hemoglobin synthesis.
Her colleague Dr Cavan Bennett has mooted a new treatment for Polycythaemia Vera, a condition of excessive red blood cells with a poor prognosis. An anti-TMPRSS6 drug raises hepcidin levels and reduces red cell production. It manages to reduce blood iron levels without reducing body stores. Patents have been applied for, and clinical trials for its use in treating Polycythaemia Vera have been started.
Gemma skilfully fielded questions from the floor on the topics of bone marrow banks, platelets, haemochromatosis, thalassaemia and malaria. It is clear that the metabolism of iron is extremely complex, and that treating anaemia in some conditions there are caveats to be aware of, as anaemia is sometimes protective. Gemma touched on the genetic differences of some communities that affect iron metabolism, before M.C. Tilak Dissanayake thanked her for her informative dissertation.
Gemma Moir-Mayer is a fifth year PhD student working in the Pasricha Lab with Professor Sant-Rayn Pasricha who heads the WHO Collaborating Centre for Anaemia Detection and Control at the Walter and Eliza Hall Institute.
Before moving to Melbourne to join his laboratory, Gemma met Sant-Rayn during her time as a Research Assistant at Oxford University where her work contributed to the understanding of rare anaemias.
Nowadays, instead of studying how iron deficiency gives rise to anaemia, she is characterising a hormone that causes iron overload in anaemias.
Iron overload can lead to organ damage, particularly in the heart, liver and endocrine system, but current therapies are limited and poorly tolerated.
Gemma's work aims to contribute new insights into drug targets for iron-loading anaemias.