FIZZ1 could enhance the angiogenic ability of rat aortic endothelial cells

Found in inflammatory zone (FIZZ1), also known as hypoxia-induced mitogenic factor (HIMF), is a secreted protein formed by 111 amino acid residues. FIZZ1 is mainly located in alveolar epithelial cells, white adipose tissue and the heart. This study aimed to explore the effects of FIZZ1 on the angiogenic ability of cultured rat aortic endothelial cells (RAECs) and the potential mechanism. The RAECs were cultured in the extracellular matrix (ECM) supplemented with 10% fetal bovine serum (FBS). Matrigel assay was used to detect the angiogenic ability of the RAECs and Agilent Rat Microarray containing 41,000 genes/ESTs was used to screen the differentially expressed genes of the RAECs after they were treated with FIZZ1 (5 x 10(-9)~2 x 10(-8) mol/L). The results were verified using RT-PCR method. We found that FIZZ1 markedly enhanced the angiogenic ability of RAECs (22.6 ± 2.94 vs. 19.7 ± 2.57, P < 0.01; 28.5 ± 3.32 vs. 19.7 ± 2.57, P < 0.01; 36.9 ± 5.01 vs. 19.7 ± 2.57, P < 0.01) in a dose-dependent manner (5 x 10(-9)~2 x 10(-8) mol/L). 440 genes (Gng8, Atg9a, Gdf6, etc.) were found to be up-regulated and 497 genes (Hbb-b1, Camk1g, etc.) down-regulated in the experimental group. Changes in Gng8 and Atg9a were revealed by RT-PCR. FIZZ1 could enhance angiogenesis of RAECs by up-regulating Gng8 and Atg9a.