Quantitative study of age-related endothelial phenotype change in the human vortex vein system

• Age-related increase in endothelial cell area throughout vortex vein system
• Regional specific endothelial heterogeneity was present in both age groups.
• Age-related changes in cell width, length and nucleus position was identified.
• Relationship between phenotype change and endothelial function needs investigation.
• Relationship between endothelial senescence and pathologic mechanism requires study.

PurposeWe have previously reported significant phenotype heterogeneity in the vortex vein system. This study is to quantify the age-related change of such endothelial phenotype heterogeneity.MethodThe inferior temporal vortex vein system of 10 eyes from 7 young donors (30 ± 4.1 years) and 9 eyes from 6 aged (72 ± 4.7 years) donors were dissected after perfusion fixation and labeled for f-actin and nucleic acid. Confocal images of endothelial cells were obtained from nine anatomic regions and measurements made of the cell and nucleus sizes. The results were compared between the two age groups.ResultsSimilar regional endothelial heterogeneity was observed in both age groups through the different regions of the vortex vein system. Age-related increase in endothelial cell area was observed in all the study regions. Age-associated regional differences were also observed in the endothelial length, width, and nucleus parameters. Endothelial nuclei were also found to be located further downstream within the cell in aged donor eyes.ConclusionAge related enlarged endothelial cells have been identified in this venous system, a likely indicator of senescence. The relationship between the endothelial senescence, regional endothelial phenotype change and endothelial dysfunction in possible pathological changes needs to be further defined.