The study, published in the Journal of Pharmacology and Experimental Therapeutics, shows researchers used a common blood pressure-lowering medication to identify factors in the brain that help it recover following a stroke. Although candesartan protects the brain after a stroke, it is avoided because low blood pressure soon after a stroke can decrease oxygen to the brain during a critical recovery period.
"The really unique thing we found is that candesartan can increase the secretion of brain derived neurotrophic factor, and the effect is separate from the blood pressure lowering effect," said Ahmed Alhusban, co-author of the study and a doctoral candidate at the University of Georgia. "This will support a new area for treatments of stroke and other brain injury."
The research shows that candesartan blocks the angiotensin II type 1 receptor in the brain, which lowers blood pressure, stimulates the AT2 receptor, and increases the secretion of brain derived neurotrophic factor (BDNF). BDNF is associated with blood vessel growth in the brain, and the AT2 receptor has been tied to the growth of new blood vessels from already existing vessels.
"BDNF is a key player in learning and memory," said Susan Fagan, research lead and assistant dean for clinical programs at University of Georgia's College of Pharmacy. "A reduction of BDNF in the brain has been associated with Alzheimer's disease and depression, so increasing this growth factor with a common medication is exciting."