October 7, 2019

Nobel Prize in Physiology or Medicine: how our cells adapt to oxygen or lack thereof.

Announcement of the Nobel Prize in Physiology or Medicine 2019

How our cells sense and respond to oxygen levels. Hypoxia Inducible Factor. Hypoxia is when there is too little oxygen. The Nobel Prize in Physiology or Medicine 2019 was awarded jointly to William G. Kaelin Jr, Sir Peter J. Ratcliffe and Gregg L. Semenza "for their discoveries of how cells sense and adapt to oxygen availability." This fundamental system regulates how our bodies respond to the level of oxygen available. It is also important in cancer tumor tissue because the system is used by tumor cells to help provide the blood supply the tumor needs to grow. Also, genes like EPO, Erythropoetin. EPO, is that the factor that Tour de France bikers were using to increase their levels of red blood cells for more oxygen? Yes. Same one. How does HIF work?

HIF is a transcription factor. Transcription factors are proteins that turn genes on or off in our cells. In this case, HIF is a transcription factor that provides the link between oxygen levels and the expression of various genes in our cells and tissues to adjust their metabolism for the available oxygen. When you need more oxygen, HIF will help to increase the expression of genes to make proteins and enzymes you need to get more oxygen into your cells and organs. Like EPO. 

In my research lab, we study the effects of increased amounts of members of the VEGFA family of proteins  (Vascular Endothelial Growth Factor-A) in the retina. VEGFA increases when retinal tissue is feeling starved of oxygen, which happens in diabetic retinopathy and retinopathy of prematurity and vascular blockages in the retina. HIF also helps to regulate the expression of the VEGFA gene. VEGFA proteins can cause new blood vessels to grow, and tumors also make use of this growth factor. Of course, HIF is very important for normal growth and development too. We could not develop in the womb nor grow into adulthood without it. 

Watch the Nobel Prize announcement here, posted on th Nobel foundation's youtube site: 


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