Premium
Tannic acid attenuates TGF‐β1‐induced epithelial‐to‐mesenchymal transition by effectively intervening TGF‐β signaling in lung epithelial cells
Author(s) -
Pattarayan Dhamotharan,
Sivanantham Ayyanar,
Krishnaswami Venkateshwaran,
Loganathan Lakshmanan,
Palanichamy Rajaguru,
Natesan Subramanian,
Muthusamy Karthikeyan,
Rajasekaran Subbiah
Publication year - 2018
Publication title -
journal of cellular physiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.529
H-Index - 174
eISSN - 1097-4652
pISSN - 0021-9541
DOI - 10.1002/jcp.26127
Subject(s) - epithelial–mesenchymal transition , transforming growth factor , a549 cell , fibronectin , myofibroblast , cancer research , vimentin , microbiology and biotechnology , chemistry , protein kinase b , pulmonary fibrosis , smad , signal transduction , extracellular matrix , biology , fibrosis , medicine , cell , immunology , downregulation and upregulation , biochemistry , immunohistochemistry , gene
Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive, and an irreversible lung disorder characterized by the accumulation of fibroblasts and myofibroblasts in the extracellular matrix. The transforming growth factor‐β1 (TGF‐β1)‐induced epithelial‐to‐mesenchymal transition (EMT) is thought to be one of the possible sources for a substantial increase in the number of fibroblasts/myofibroblasts in IPF lungs. Tannic acid (TA), a natural dietary polyphenolic compound has been shown to possess diverse pharmacological effects. However, whether TA can inhibit TGF‐β1‐mediated EMT in lung epithelial cells remains enigmatic. Both the human adenocarcinomic alveolar epithelial (A549) and normal bronchial epithelial (BEAS‐2B) cells were treated with TGF‐β1 with or without TA. Results showed that TA addition, markedly inhibited TGF‐β1‐induced EMT as assessed by reduced expression of N‐cadherin, type‐1‐collagen, fibronectin, and vimentin. Furthermore, TA inhibited TGF‐β1‐induced cell proliferation through inducing cell cycle arrest at G0/G1 phase. TGF‐β1‐induced increase in the phosphorylation of Smad (Smad2 and 3), Akt as well as that of mitogen activated protein kinase (ERK1/2, JNK1/2, and p38) mediators was effectively inhibited by TA. On the other hand, TA reduced the TGF‐β1‐induced increase in TGF‐β receptors expression. Using molecular docking approach, FTIR, HPLC and Western blot analyses, we further identified the direct binding of TA to TGF‐β1. Finally, we conclude that TA might directly interact with TGF‐β1, thereby repressing TGF‐β signaling and subsequent EMT process in lung epithelial cells. Further animal studies are needed to clarify its potential therapeutic benefit in pulmonary fibrosis.