Basic Study
Copyright ©The Author(s) 2023. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. May 14, 2023; 29(18): 2798-2817
Published online May 14, 2023. doi: 10.3748/wjg.v29.i18.2798
Calcitriol attenuates liver fibrosis through hepatitis C virus nonstructural protein 3-transactivated protein 1-mediated TGF β1/Smad3 and NF-κB signaling pathways
Liu Shi, Li Zhou, Ming Han, Yu Zhang, Yang Zhang, Xiao-Xue Yuan, Hong-Ping Lu, Yun Wang, Xue-Liang Yang, Chen Liu, Jun Wang, Pu Liang, Shun-Ai Liu, Xiao-Jing Liu, Jun Cheng, Shu-Mei Lin
Liu Shi, Xiao-Jing Liu, Shu-Mei Lin, Department of Infectious Disease Medicine, The First Hospital Affiliated to Xi’an Jiaotong University, Xi’an 710061, Shaanxi Province, China
Li Zhou, China-Japan Friendship Hospital, Department of Infectious Disease China-Japan Friendship Hospital, Beijing 100029, China
Ming Han, Yang Zhang, Xiao-Xue Yuan, Chen Liu, Pu Liang, Shun-Ai Liu, Jun Cheng, Institute of Infectious Diseases, Beijing Ditan Hospital, Capital Medical University, Beijing 100015, China
Yu Zhang, Yun Wang, The Division of Liver Diseases, Beijing Ditan Hospital, Capital Medical University, Beijing 100015, China
Hong-Ping Lu, Institute of Liver Diseases, Beijing Pan-Asia Tongze Institute of Biomedicine Co., Ltd, Beijing 100015, China
Xue-Liang Yang, Department of Rehabilitation Medicine, The First Affiliated Hospital of Xi’an Jiaotong University, Xi’an 710061, Shaanxi Province, China
Jun Wang, Beijing Key Laboratory of Emerging Infectious Diseases, Peking University Ditan Teaching Hospital, Beijing 100015, China
Author contributions: Shi L, Zhou L, Han M, Zhang Y, Zhang Y, Yuan XX, Lu HP, Wang Y, Yang XL, Liu C, Wang J, Liang P, Liu SA, Liu XJ, Cheng J, and Lin SM contributed to the study conception and design; Liu S, Li Z, Ming H, Yu Z, Yang Z, Xue YX, Ping LH, Yun W, Liang YX, Chen L, Jun W, and Jing LX participated in the design and completion of the experiment; Liu S wrote the original draft; Liu S, Jun C, and Mei LS reviewed and edited the manuscript; Pu L and Ai LS finished the project administration; Jun C and Mei LS have the same contribution to the article; all authors approved the final version of the article.
Supported by the National Key Research and Development Program of China, No. 2017YFC0908104; and National Science and Technology Projects, No. 2017ZX10203201, No. 2017ZX10201201, and No. 2017ZX10202202.
Institutional animal care and use committee statement: All procedures involving animals were reviewed and approved by the Institutional Animal Care and Use Committee at Xi’an Jiaotong University Medical Science Center (approval No. 2020-1739).
Conflict-of-interest statement: The authors declare that they have no competing interests.
Data sharing statement: No additional data are available.
ARRIVE guidelines statement: The authors have read the ARRIVE guidelines, and the manuscript was prepared and revised according to the ARRIVE guidelines.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See:
Corresponding author: Shu-Mei Lin, Doctor, MD, PhD, Doctor, Professor, Teacher, Department of Infectious Disease Medicine, The First Hospital Affiliated to Xi’an Jiaotong University, No. 277 Yanta West Road, Yanta, Xi’an 710061, Shaanxi Province, China.
Received: December 13, 2022
Peer-review started: December 13, 2022
First decision: February 23, 2023
Revised: March 8, 2023
Accepted: April 10, 2023
Article in press: April 10, 2023
Published online: May 14, 2023

Hepatic fibrosis is a serious condition, and the development of hepatic fibrosis can lead to a series of complications. However, the pathogenesis of hepatic fibrosis remains unclear, and effective therapy options are still lacking. Our group identified hepatitis C virus nonstructural protein 3-transactivated protein 1 (NS3TP1) by suppressive subtractive hybridization and bioinformatics analysis, but its role in diseases including hepatic fibrosis remains undefined. Therefore, additional studies on the function of NS3TP1 in hepatic fibrosis are urgently needed to provide new targets for treatment.


To elucidate the mechanism of NS3TP1 in hepatic fibrosis and the regulatory effects of calcitriol on NS3TP1.


Twenty-four male C57BL/6 mice were randomized and separated into three groups, comprising the normal, fibrosis, and calcitriol treatment groups, and liver fibrosis was modeled by carbon tetrachloride (CCl4). To evaluate the level of hepatic fibrosis in every group, serological and pathological examinations of the liver were conducted. TGF-β1 was administered to boost the in vitro cultivation of LX-2 cells. NS3TP1, α-smooth muscle actin (α-SMA), collagen I, and collagen III in every group were examined using a Western blot and real-time quantitative polymerase chain reaction. The activity of the transforming growth factor beta 1 (TGFβ1)/Smad3 and NF-κB signaling pathways in each group of cells transfected with pcDNA-NS3TP1 or siRNA-NS3TP1 was detected. The statistical analysis of the data was performed using the Student’s t test.


NS3TP1 promoted the activation, proliferation, and differentiation of hepatic stellate cells (HSCs) and enhanced hepatic fibrosis via the TGFβ1/Smad3 and NF-κB signaling pathways, as evidenced by the presence of α-SMA, collagen I, collagen III, p-smad3, and p-p65 in LX-2 cells, which were upregulated after NS3TP1 overexpression and downregulated after NS3TP1 interference. The proliferation of HSCs was lowered after NS3TP1 interference and elevated after NS3TP1 overexpression, as shown by the luciferase assay. NS3TP1 inhibited the apoptosis of HSCs. Moreover, both Smad3 and p65 could bind to NS3TP1, and p65 increased the promoter activity of NS3TP1, while NS3TP1 increased the promoter activity of TGFβ1 receptor I, as indicated by coimmunoprecipitation and luciferase assay results. Both in vivo and in vitro, treatment with calcitriol dramatically reduced the expression of NS3TP1. Calcitriol therapy-controlled HSCs activation, proliferation, and differentiation and substantially suppressed CCl4-induced hepatic fibrosis in mice. Furthermore, calcitriol modulated the activities of the above signaling pathways via downregulation of NS3TP1.


Our results suggest that calcitriol may be employed as an adjuvant therapy for hepatic fibrosis and that NS3TP1 is a unique, prospective therapeutic target in hepatic fibrosis.

Keywords: Nonstructural protein 3-transactivated protein 1, Calcitriol, Liver fibrosis, Hepatic stellate cells, Mouse model, TGFβ1/Smad3, NF-κB, Signaling pathway

Core Tip: We proved that hepatitis C virus nonstructural protein 3-transactivated protein 1 (NS3TP1) promoted hepatic fibrosis via the transforming growth factor beta 1/Smad3 and NF-κB signaling pathways. Calcitriol attenuates liver fibrosis through NS3TP1-mediated above both signaling pathways. These novel findings profoundly expand our knowledge about the mechanisms underlying the role and function of NS3TP1 in hepatic fibrosis. The relationship between NS3TP1 and liver fibrosis was discussed for the first time and provided a foundation for research related to liver fibrosis by targeting NS3TP1. We first showed that calcitriol alleviated hepatic fibrosis through the above signaling pathways via NS3TP1.