Hypoxia Inducible Factor (HIF) 1-Α dan Vascular Endothelial Growth Factor (VEGF) pada Stroke Iskemik Fase Akut

Ischemic stroke is one of the most common causes of stroke, caused by cerebral vascular occlusion and the third cause of death. When the onset of an ischemic stroke occurs, the area of the brain bleeding by blood vessels will lack oxygen and nutrients so that brain cells, especially neurons, are at risk, these neurons can still function known as penumbra. Hypoxic, one of the characteristics of penumbra is the main stimulus for regulation of HIF-1α protein. Hypoxia itself is the main stimulus of ischemic precondition. The ischemic precondition will produce a hypoxic-resistant phenotype namely protein hypoxia inducible factor (HIF) -1α. HIF-1αis the only substance released by tissue that experiences hypoxia. HIF-1α acts as a signaling protein that can regulate other protein genes. Effectors of HIF-1αinclude erythropoitin and vascular endothelial growth factor (VEGF). Growth, differentiation and endurance of endothelial cells are regulated by VEGF stimulated from HIF-1α. During cerebral ischemia, damaged tissue tries to increase oxygen delivery through induction of angiogenesis through VEGF production. This is characterized by an increase in the number of micro blood vessels in the infarct area. VEGF and its receptors are regulated by HIF-1α in the first day of ischemia.