Aucubin ameliorates liver fibrosis and hepatic stellate cells activation in diabetic mice via inhibiting ER stress-mediated IRE1α/TXNIP/NLRP3 inflammasome through NOX4/ROS pathway.

Abstract

Type 2 diabetes (T2DM) is closely associated with hepatic injury, which could promote/exacerbate hepatic inflammation, steatosis, and accelerate liver fibrosis progression. Aucubin (AU), as an active ingredient isolated from Eucommia ulmoides, exists a nutritional value in hepatoprotective effect and diabetic complications. However, whether it possesses more outstanding features on improving liver injury in diabetic conditions and the underlying mechanism is unclear. Our research investigated the treatment of AU on liver fibrosis and potential mechanisms on high-fat diet/streptozotocin-induced diabetic mice and high glucose (HG)&TGF-β1-induced LX-2 cells. Results showed that AU restored hepatic function without affecting blood sugar levels in diabetic mice. Meanwhile, the enhanced levels of total cholesterol, triglycerides, and LDL-c were reversed in hepatic tissue after AU treatment. Histomorphology assays including H&E, Masson, PAS, Oil red and Sirius red staining showed that AU treatment reduced liver swelling, steatosis and fibrosis. Mechanistic studies showed that AU alleviated NLRP3 inflammasome activation and inflammatory responses via inhibiting ER stress-mediated IRE1α/TXNIP signaling pathway, which could postpone the development of T2DM induced hepatic fibrosis. In addition, the ROS generation and the up-regulated expression of NADHP oxidase 4 (NOX4) in the liver tissue were suppressed by AU treatment. Moreover, in vitro model, NOX4 activation was prominently enhanced and AU treatment blocked HG&TGF-β1-induced NOX4 derived superoxide generation and thereby ameliorating hepatic stellate cell activation, which can be abrogated in the overexpression of NOX4 LX-2 cells. In addition, inhibition effects on ER stress-mediated IRE1α/TXNIP/NLRP3 inflammasome by AU treatment also were abolished in the overexpression of NOX4 LX-2 cells. Meanwhile, molecular docking results indicated that AU and NOX4 protein have a higher affinity. Taken together, AU might be a potential nutraceutical or therapeutic drug to ameliorate hepatic impairment and fibrosis in T2DM.

• Authors: Xiaowen Bao, Jiaqi Li, Chaoxing Ren, Jingxun Wei, Xuanzhao Lu, Xiaoxuan Wang, Wei Du, Xin Jin, Beiting Ma, Qi Zhang, Bo Ma
• Journal: Chemico-biological interactions (Chem Biol Interact) Vol. 365 Pg. 110074 (Sep 25 2022) ISSN: 1872-7786 [Electronic] Ireland
• PMID: 35961541 (Publication Type: Journal Article)
• Copyright: Copyright © 2022 Elsevier B.V. All rights reserved.

Chemical References

• Carrier Proteins
• Inflammasomes
• Iridoid Glucosides
• NLR Family, Pyrin Domain-Containing 3 Protein
• Nitrosamines
• Nlrp3 protein, mouse
• Reactive Oxygen Species
• Transforming Growth Factor beta1
• Txnip protein, mouse
• aucubin
• Thioredoxins
• N-nitrosoallyl-2,3-dihydroxypropylamine
• Oxidoreductases
• NADPH Oxidase 4
• Nox4 protein, mouse
• Protein Serine-Threonine Kinases
• Endoribonucleases

Topics

• Animals
• Carrier Proteins
• Diabetes Mellitus, Experimental (drug therapy, metabolism)
• Diabetes Mellitus, Type 2 (metabolism)
• Endoribonucleases (metabolism)
• Fibrosis
• Hepatic Stellate Cells (metabolism)
• Inflammasomes (metabolism)
• Iridoid Glucosides
• Liver Cirrhosis (chemically induced, drug therapy, metabolism)
• Mice
• Molecular Docking Simulation
• NADPH Oxidase 4 (metabolism)
• NLR Family, Pyrin Domain-Containing 3 Protein (metabolism)
• Nitrosamines
• Oxidoreductases (metabolism)
• Protein Serine-Threonine Kinases
• Reactive Oxygen Species (metabolism)
• Thioredoxins
• Transforming Growth Factor beta1 (metabolism)