Reactive Oxygen Species and p38MAPK Have a Role in the Smad2 Linker Region Phosphorylation Induced by TGF-β
Journal Title: Iranian Journal of Medical Sciences - Year 2018, Vol 43, Issue 4
Abstract
Background: Transforming growth factor-β (TGF-β) in addition to the C-terminal region can phosphorylate receptor-regulated Smads (R-Smads) in their linker region. The aim of the present study was to evaluate the role of signaling mediators such as NAD(P)H oxidases (reactive oxygen species [ROS] generators), ROS, and ROS-sensitive p38 mitogen-activated protein kinase (p38MAPK) in this signaling pathway in cultured human vascular smooth muscle cells (VSMCs). Methods: The present in vitro study was performed on human VSMCs. Proteins were detected by western blotting utilizing an anti-phospho-Smad2 (Ser245/250/255) rabbit polyclonal antibody and a horseradish peroxidase-labeled secondary antibody. Glyceraldehyde-3-phosphate dehydrogenase was used as a loading control. The phospho-Smad2 linker region (pSmad2L) was detected in all the experimental groups: a control group (untreated group), a group treated with TGF-β (2 ng/mL), and a group treated with TGF-β plus different inhibitors. The data were normalized and presented as mean±SEM. The statistical analyses were performed using SPSS, version 16.0, and the nonparametric Kruskal–Wallis test. A P value smaller than 0.05 was considered statistically significant. Results: The VSMCs treated with TGF-β (2 ng/mL) showed a time-dependent increase in the pSmad2L level. The highest level was observed at 15 minutes (P=0.03). The inhibitors of NAD(P)H oxidases (diphenyleneiodonium and apocynin) (P=0.04), ROS scavenger (N-acetylcysteine) (P=0.04), and p38MAPK inhibitor (SB-202190) (P=0.04) were able to reduce the increased level of the pSmad2L by TGF-β. Conclusion: Our results suggested that NAD(P)H oxidases played an important role in the Smad2L phosphorylation in the human VSMCs. Furthermore, our results confirmed that ROS and p38MAPK were involved in this signaling pathway. Thus, TGF-β via a ROS-dependent mechanism can transmit its signals to the pSmad2L.
Authors and Affiliations
Reyhaneh Niayesh Mehr, Alireza Kheirollah, Faezeh Seif, Parisa Dayati, Hossein Babaahmadi Rezaei
Keywords
Related Articles
- EP ID EP355509
- DOI -
- Views 78
- Downloads 0
Optimization of the Static Human Osteoblast/Osteoclast Co-culture System
Osteoblasts (OBs) and osteoclasts (OCs) are 2 major groups of bone cells. Their cell-to-cell interactions are important to ensure the continuity of the bone-remodeling process. Therefore, the present study was carried ou...
Bilateral Hyperplasia of Bartholin’s Gland: A Case Report
A 37-year-old woman underwent surgery to remove bilateral vulvar masses. The masses were firm, non-tender, and immobile. Pathologic finding was a well-delineated creamy grayish mass with a homogenous grayish solid surfac...
Assessment of Speech Sound Production by Story-retelling in Persian Speaking Children: Introducing a New Instrument
Background: Speech and language pathologists should include connected speech assessment as part of their evaluation for children with speech sound disorders. The purpose of the present study was to design and validate an...
Adherence to the CONSORT Statement in the Reporting of Randomized Controlled Trials on Pharmacological Interventions Published in Iranian Medical Journals
Background: Among manuscripts submitted to biomedical journals, randomized controlled trials (RCTs) form the backbone of evidence-based medicine. Hence, their protocol should be designed rigorously and their results shou...
Impact of the Polymorphism of the PACRG and CD80 Genes on the Development of the Different Stages of Tuberculosis Infection
Background: Tuberculosis (TB) is one of the most significant health-care problems worldwide. The host’s genetics play an important role in the development of TB in humans. The disease progresses through several stages, e...