Characterization of TGF-β by Induced Oxidative Stress in Human Trabecular Meshwork Cells

• Main Authors: Hsin-Yi Chen (Author), Hsiu-Chuan Chou (Author), Yi-Jung Ho (Author), Shing-Jyh Chang (Author), En-Chi Liao (Author), Yu-Shan Wei (Author), Meng-Wei Lin (Author), Yi-Shiuan Wang (Author), Yu-An Chien (Author), Xin-Ru Yu (Author), Hsiang-Yu Kung (Author), Chu-Chun Yang (Author), Jia-Yu Chen (Author), Hong-Lin Chan (Author), Mei-Lan Ko (Author)
• Format: Book
• Published: MDPI AG, 2021-01-01T00:00:00Z.
• Subjects: article
• Online Access: Connect to this object online.

Summary

Oxidative stress generated by reactive oxygen species (ROS) plays a critical role in the pathomechanism of glaucoma, which is a multifactorial blinding disease that may cause irreversible damage within human trabecular meshwork cells (HTMCs). It is known that the transforming growth factor-β (TGF-β) signaling pathway is an important component of oxidative stress-induced damage related to extracellular matrix (ECM) fibrosis and activates cell antioxidative mechanisms. To elucidate the dual potential roles and regulatory mechanisms of TGF-β in effects on HTMCs, we established an in vitro oxidative model using hydrogen peroxide (H₂O₂) and further focused on TGF-β-related oxidative stress pathways and the related signal transduction. Via a series of cell functional qualitative analyses to detect related protein level alterations and cell fibrosis status, we illustrated the role of TGF-β1 and TGF-β2 in oxidative stress-induced injury by shTGF-β1 and shTGF-β2 knockdown or added recombinant human TGF-β1 protein (rhTGF-β1). The results of protein level showed that p38 MAPK, TGF-β, and its related SMAD family were activated after H₂O₂ stimulation. Cell functional assays showed that HTMCs with H₂O₂ exposure duration had a more irregular actin architecture compared to normal TM cells. Data with rhTGF-β1 (1 ng/mL) pretreatment reduced the cell apoptosis rate and amount of reactive oxygen species (ROS), while it also enhanced survival. Furthermore, TGF-β1 and TGF-β2 in terms of antioxidant signaling were related to the activation of collagen I and laminin, which are fibrosis-response proteins. Succinctly, our study demonstrated that low concentrations of TGF-β1 (1 ng/mL) preserves HTMCs from free radical-mediated injury by p-p38 MAPK level and p-AKT signaling balance, presenting a signaling transduction mechanism of TGF-β1 in HTMC oxidative stress-related therapies.

Item Description

10.3390/antiox10010107
2076-3921