A bioinformatic and mechanistic study elicits the antifibrotic effect of ursolic acid through the attenuation of oxidative stress with the involvement of ERK, PI3K/Akt, and p38 MAPK signaling pathways in human hepatic stellate cells and rat liver.
NADPH oxidases (NOXs) are a predominant mediator of redox homeostasis in hepatic stellate cells (HSCs), and oxidative stress plays an important role in the pathogenesis of liver fibrosis. Ursolic acid (UA) is a pentacyclic triterpenoid with various pharmacological activities, but the molecular targets and underlying mechanisms for its antifibrotic effect in the liver remain elusive. This study aimed to computationally predict the molecular interactome and mechanistically investigate the antifibrotic effect of UA on oxidative stress, with a focus on NOX4 activity and cross-linked signaling pathways in human HSCs and rat liver. Drug-drug interaction via chemical-protein interactome tool, a server that can predict drug-drug interaction via chemical-protein interactome, was used to predict the molecular targets of UA, and Database for Annotation, Visualization, and Integrated Discovery was employed to analyze the signaling pathways of the predicted targets of UA. The bioinformatic data showed that there were 611 molecular proteins possibly interacting with UA and that there were over 49 functional clusters responding to UA. The subsequential benchmarking data showed that UA significantly reduced the accumulation of type I collagen in HSCs in rat liver, increased the expression level of MMP-1, but decreased the expression level of TIMP-1 in HSC-T6 cells. UA also remarkably reduced the gene expression level of type I collagen in HSC-T6 cells. Furthermore, UA remarkably attenuated oxidative stress via negative regulation of NOX4 activity and expression in HSC-T6 cells. The employment of specific chemical inhibitors, SB203580, LY294002, PD98059, and AG490, demonstrated the involvement of ERK, PI3K/Akt, and p38 MAPK signaling pathways in the regulatory effect of UA on NOX4 activity and expression. Collectively, the antifibrotic effect of UA is partially due to the oxidative stress attenuating effect through manipulating NOX4 activity and expression. The results suggest that UA may act as a promising antifibrotic agent. More studies are warranted to evaluate the safety and efficacy of UA in the treatment of liver fibrosis.
Department of Gastroenterology, the First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, People's Republic of China.
Wenhua
W
He
Department of Gastroenterology, the First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, People's Republic of China.
Feng
F
Shi
Department of Pharmaceutical Sciences, College of Pharmacy, University of South Florida, Tampa, FL, USA.
Zhi-Wei
ZW
Zhou
Department of Gastroenterology, the First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, People's Republic of China.
Bimin
B
Li
Department of Gastroenterology, the First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, People's Republic of China.
Kunhe
K
Zhang
Department of Gastroenterology, the First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, People's Republic of China.
Xinhua
X
Zhang
Department of Gastroenterology, the First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, People's Republic of China.
Canhui
C
Ouyang
Department of Pharmaceutical Sciences, College of Pharmacy, University of South Florida, Tampa, FL, USA.
Shu-Feng
SF
Zhou
Department of Gastroenterology, the First Affiliated Hospital of Nanchang University, Nanchang, Jiangxi, People's Republic of China.
Xuan
X
Zhu
D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects; D024042:Collagen Type I / Q000235:genetics / Q000378:metabolism; D019295:Computational Biology; D004128:Dimethylnitrosamine; D004305:Dose-Response Relationship, Drug; D048049:Extracellular Signal-Regulated MAP Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D005786:Gene Expression Regulation; D055166:Hepatic Stellate Cells / Q000187:drug effects* / Q000201:enzymology / Q000473:pathology; D006801:Humans; D008099:Liver / Q000187:drug effects* / Q000201:enzymology / Q000473:pathology; D008106:Liver Cirrhosis, Experimental / Q000139:chemically induced / Q000188:drug therapy* / Q000201:enzymology / Q000473:pathology; D008297:Male; D020781:Matrix Metalloproteinase 1 / Q000378:metabolism; D000074663:NADPH Oxidase 4; D019255:NADPH Oxidases / Q000378:metabolism; D018384:Oxidative Stress / Q000187:drug effects*; D058539:Phosphatidylinositol 3-Kinase / Q000378:metabolism*; D000081082:Phosphoinositide-3 Kinase Inhibitors; D060066:Protein Interaction Maps; D047428:Protein Kinase Inhibitors / Q000494:pharmacology; D051057:Proto-Oncogene Proteins c-akt / Q000037:antagonists & inhibitors / Q000378:metabolism; D017207:Rats, Sprague-Dawley; D015398:Signal Transduction / Q000187:drug effects; D013997:Time Factors; D019715:Tissue Inhibitor of Metalloproteinase-1 / Q000378:metabolism; D014315:Triterpenes / Q000494:pharmacology*; D048051:p38 Mitogen-Activated Protein Kinases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D000097245:Ursolic Acid
D000975:Antioxidants; D024042:Collagen Type I; D004128:Dimethylnitrosamine; D048049:Extracellular Signal-Regulated MAP Kinases; D020781:Matrix Metalloproteinase 1; D000074663:NADPH Oxidase 4; D019255:NADPH Oxidases; D058539:Phosphatidylinositol 3-Kinase; D000081082:Phosphoinositide-3 Kinase Inhibitors; D047428:Protein Kinase Inhibitors; D051057:Proto-Oncogene Proteins c-akt; D019715:Tissue Inhibitor of Metalloproteinase-1; D014315:Triterpenes; D048051:p38 Mitogen-Activated Protein Kinases; D000097245:Ursolic Acid; C576839:TIMP1 protein, rat; C498910:NOX4 protein, human; C498911:Nox4 protein, rat; C576840:MMP1 protein, rat
DAVID; DDI-CPI; NADPH oxidase; ROS; liver fibrosis; ursolic acid