Abstract
Purpose :
Angiopoietin-1 (Ang-1) is expressed by cells in the perivascular wall and some mesenchymal cells, and regulates vascular structural stability and angiogenesis via Tie2 receptors. Reactive oxygen species (ROS) play an important role in cell apoptosis induced by mechanical stretch stimuli. In this study, we measured and evaluated the expression of Ang-1 in a human Müller cell line in response to a mechanical stretch stimulus, and discussed its relationship to ROS.
Methods :
The human Müller cell line, MIO-M1, was cultured in collagen I-coated 6-well plates and subjected to mechanical stretch mimicking the cardiac cycle using a Flexcell cell stretching device. Diphenyleneiodonium (DPI) and N-acetyl-L-cysteine (NAC) were added, and Ang-1 expression levels were measured by the real-time polymerase chain reaction and compared with and without these treatments.
Results :
The expression of Ang-1 decreased 0.72 ± 0.04-fold (p = 0.001), 0.62 ± 0.08-fold (p = 0.001), and 0.58 ± 0.03-fold (p = 0.001) with prolonged mechanical stretch stimulation at 10%/60 cpm, the physiological stretch frequency, for 1, 3, and 6 h, respectively. This decrease in Ang-1 expression was reversed by DPI, an NADPH oxidase inhibitor, and NAC, an ROS scavenger.
Conclusions :
The stretch stimulus-dependent decrease in Ang-1 expression in Müller cells may be due to increased intracellular oxidative stress caused by activation of intracellular NADPH oxidase.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.