Fig. 1From: Hypoxia exposure blunts angiogenic signaling and upregulates the antioxidant system in endothelial cells derived from elephant sealsPrimary elephant seal arterial endothelial cells express canonical endothelial markers and modulate cellular respiration in response to hypoxia/reoxygenation. A Top: PECAM-1 (CD31; green) staining in seal and human endothelial cells. Middle: DiI-acetylated LDL (red) uptake by seal and human cells. Nuclei (blue) in the top and middle panels are stained with Hoechst 33342. Lower: Seal and human endothelial cells spontaneously form tubes when cultured in a 3D gel matrix. B Relative mRNA expression levels of the endothelial markers VE-cadherin (CD144) and PECAM-1 (CD31) in seal endothelial (purple) compared to placental trophoblast (red) cells, n = 3–5 replicates per group. Individual points are shown as white circles with gray borders. *p < 0.05. C Mitochondrial function at baseline and after hypoxia/reoxygenation in seal and human cells. Values are normalized to protein content per well. hxrx, hypoxia/reoxygenation. *p < 0.05 between species at baseline. †p < 0.05 between species after hypoxia/reoxygenation. Lettering indicates intraspecific changes between baseline and hypoxia/reoxygenation, n = 9 per group. D Extracellular acidification rate (ECAR) in seal and human endothelial cells at baseline and after hypoxia/reoxygenation, n = 9 per group. E, F Mitochondrial footprint (E) and mean mitochondrial network branch length (F) in seal and human endothelial cells after hypoxia/reoxygenation. Hypoxia exposure occurred for 1 or 6 h, followed by 30 min reoxygenation. Lettering indicates intraspecific changes between baseline and hypoxia/reoxygenation, n = 13–28 cells per group. G Representative images of human (top) and seal (bottom) endothelial cells stained with MitoTracker Red CMXRos after 0, 1, and 6 h hypoxia followed by 30 min reoxygenation. See Additional file 1: Fig. S1 for additional representative images. Scale bar in all images is 50 µmBack to article page