For the second time in a week Dr. Jayakrishna Ambati, University of Kentucky (UK) HealthCare physician and associate professor and vice chair of the Department of Ophthalmology and Visual Sciences, announced a discovery from his lab that will affect the future of macular degeneration treatment and research.
Vascular endothelial growth factor (VEGF) is a substance that promotes angiogenesis, which is the formation of new blood vessels from pre-existing vessels. In macular degeneration, vessels grow through angiogenesis, destroying the cells that are required for vision. Scientists have long believed that turning off the source of VEGF would lead to halting angiogenesis and disease progression.
Ambati’s lab found that while withdrawing VEGF could halt angiogenesis in some areas, it actually encouraged it in others. Upon further investigation Ambati found that this previously undiscovered process that stopped the growth of new blood vessels was mediated by activating VEGF receptor 1 and deactivating VEGF receptor 2. A receptor is a molecular structure or site on the surface or interior of a cell that binds with substances such as hormones, drugs, or neurotransmitters, for example).
Additionally, his lab found that a compound known as SPARC could influence and switch the routing of VEGF away from VEGF receptor 1. Thus, controlling SPARC levels appears to be key to controlling angiogenesis in macular degeneration.
These surprising findings have far-reaching implications beyond ophthalmology and into all areas of medicine because new blood vessel growth is also the process by which other growths spread in the body, including malignant tumors.
Ambati’s work has opened the door into methods of controlling angiogenesis and its effects. Ambati’s paper can be found in the February 2006 issue of the Journal of Clinical Investigation.
Adapted from the following source: University of Kentucky