eRF3b-37 inhibits the TGF-β1-induced activation of hepatic stellate cells by regulating cell proliferation, G0/G1 arrest, apoptosis and migration

Abstract

The therapeutic management of liver fibrosis remains an unresolved clinical problem. The activation of hepatic stellate cells (HScs) serves a pivotal role in the formation of liver fibrosis. In our previous study, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALdI-TOF MS) was employed to identify potential serum markers for liver cirrhosis, such as eukaryotic peptide chain releasing factor 3b polypeptide (eRF3b-37), which was initially confirmed by our group to serve a protective role in liver tissues in a c-c motif chemokine ligand 4-induced liver cirrhosis mouse model. Therefore, eRF3b-37 was hypothesized to affect the activation state of HScs, which was determined by the expression of pro-fibrogenic associated factors in HSCs. In the present study, peptide synthesis technology was employed to elucidate the role of eRF3b-37 in the expression of pro-fibrogenic factors induced by transforming growth factor-β1 (TGF-β1) in LX-2 cells that were treated with either control, TGF-β1 and TGF-β1+eRF3b-37. 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyltetrazolium bromide and flow cytometric assays, and fluorescent microscope examinations were performed to evaluate the effects of eRF3b-37 on proliferation viability, G 0 /G 1 arrest, apoptosis and cell migration. The results of the present study indicated that eRF3b-37 inhibited the activation of HScs. The increased mRNA and protein expression of the pro-fibrogenic factors collagen I, connective tissue growth factor and α-smooth muscle actin (SMA) stimulated by TGF-β1 were reduced by eRF3b-37 via the following mechanisms: i) Inhibiting LX-2 cell proliferation, leading to G 0 /G 1 cell cycle arrest and inhibition of dNA synthesis by downregulating the mRNA expressions of cyclin d1 and cyclin dependent kinase-4, and upregulating the levels of P21; ii) increasing cell apoptosis by upregulating the mRNA level of B-cell lymphoma-2 (Bcl-2)-associated X protein (Bax) and Fas, and downregulating the expression of Bcl-2; and iii) reducing cell migration by downregulating the mRNA and protein expression of α-SMA. In addition, eRF3b-37 is thought to serve a role in HScs by inhibiting TGF-β signaling. Therefore, eRF3b-37 may be a novel therapeutic agent for targeting HScs for hepatic fibrosis.

Mitochondria-targeted reactive oxygen species blockor SS-31 blocks hepatic stellate cell activation and alleviates hepatic fibrosis by regulating NLRP3 inflammasomes

“…A well-known fact is that activated HSCs are the main source of stroma-secreting myofibroblasts that cause liver fibrosis [29]. In an activated state, the proliferation capacity of HSCs is promoted, and apoptosis is reduced [30]. Our results showed that SS-31 could block the proliferation of TGF-β1-activated LX2 cells and promote cell apoptosis, suggesting that SS-31 could effec-tively block HSC activation.…”

Forsythiaside A Regulates Activation of Hepatic Stellate Cells by Inhibiting NOX4-Dependent ROS

“…As we all know, activated HSCs are the major cellular source of matrix protein-secreting myofibroblasts which are the major driver of liver fibrogenesis [ 5 ]. When TGF- β 1 induced HSCs activation, the proliferation and migration ability were significantly upregulated, and cell apoptosis was decreased [ 35 ]. Our results showed that FA at a safe dose could significantly inhibit the proliferation and migration of LX2 cells induced by TGF- β 1, indicating that FA could effectively inhibit the activation of HSCs.…”

Hydroxycamptothecin Prevents Fibrotic Pathways in Fibroblasts In Vitro

“…It proves to promote the differentiation of fibroblasts into α‐SMA‐positive myofibroblasts and myofibroblasts proliferation by mediating different signaling pathways, including canonical Smad2/3 pathway and noncanonical pathways . In addition, several researchers pointed out that TGF‐β1 could regulate cell cycle and promote cell proliferation . Herein, TGF‐β1 appears to play an important role in the development of tendon fibrosis.…”