Chunwei Cheng1, Jun Tan1, Wei Qian1, Lei Zhang2, Xiaohua Hou3. 1. Division of Gastroenterology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China. 2. Division of Gastroenterology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China. Electronic address: zhanglei2017@hust.edu.cn. 3. Division of Gastroenterology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 430022, China. Electronic address: houxh@hust.edu.cn.
Abstract
AIMS: Gut inflammation has been put forward to be associated with hepatic injury in the clinical practice. The dismantled intestinal barrier was highly concerned, however, largely unknown about the role of gut-vascular barrier (GVB) in this process. This study aimed to investigate if inflamed gut directly contributes to the progression of non-alcoholic steatohepatitis (NASH), especially attention to the GVB dysfunction. MAIN METHODS: Male C57bl/6 mice were fed with a high-fat diet (HFD) and 1% DSS for 12 weeks. The colonic inflammatory injury as well as hepatic injury were evaluated. The GVB function was assessed via measuring the permeability to fluorescently-labeled dextran (70 kDa) and the expression of plasmalemma vesicle-associated protein-1 (PV1). Furthermore, the plasma endotoxin level and hepatic TLR4/TLR9 mRNA expression were detected. KEY FINDINGS: There were evident colitis in DSS-exposed mice, which trend to be more apparent in HFD ones. The HFD + DSS mice exhibited more serious hepatic steatosis, inflammation and fibrosis than HFD groups. The downregulated tight junction protein in HFD + DSS mice indicated loss of epithelial barrier. The GVB disruption were also confirmed with increased permeability to macromolecules and high expression of endothelial PV1 in HFD + DSS mice. Accordingly, potentially elevated plasma endotoxin levels and markedly increased TLR4/TLR9 mRNA expression were demonstrated in HFD + DSS mice rather than HFD groups. SIGNIFICANCE: Gut inflammation exacerbates liver injury and fibrosis in HFD mice, which may contribute to the development of NASH. Beyond the damaged intestinal epithelial barrier, GVB disruption with bacterial translocation into may play a key role in the pathogenesis of NASH.
AIMS: Gut inflammation has been put forward to be associated with hepatic injury in the clinical practice. The dismantled intestinal barrier was highly concerned, however, largely unknown about the role of gut-vascular barrier (GVB) in this process. This study aimed to investigate if inflamed gut directly contributes to the progression of non-alcoholic steatohepatitis (NASH), especially attention to the GVB dysfunction. MAIN METHODS: Male C57bl/6 mice were fed with a high-fat diet (HFD) and 1% DSS for 12 weeks. The colonic inflammatory injury as well as hepatic injury were evaluated. The GVB function was assessed via measuring the permeability to fluorescently-labeled dextran (70 kDa) and the expression of plasmalemma vesicle-associated protein-1 (PV1). Furthermore, the plasma endotoxin level and hepatic TLR4/TLR9 mRNA expression were detected. KEY FINDINGS: There were evident colitis in DSS-exposed mice, which trend to be more apparent in HFD ones. The HFD + DSS mice exhibited more serious hepatic steatosis, inflammation and fibrosis than HFD groups. The downregulated tight junction protein in HFD + DSS mice indicated loss of epithelial barrier. The GVB disruption were also confirmed with increased permeability to macromolecules and high expression of endothelial PV1 in HFD + DSS mice. Accordingly, potentially elevated plasma endotoxin levels and markedly increased TLR4/TLR9 mRNA expression were demonstrated in HFD + DSS mice rather than HFD groups. SIGNIFICANCE: Gut inflammation exacerbates liver injury and fibrosis in HFD mice, which may contribute to the development of NASH. Beyond the damaged intestinal epithelial barrier, GVB disruption with bacterial translocation into may play a key role in the pathogenesis of NASH.
Authors: Piero Portincasa; Leonilde Bonfrate; Mohamad Khalil; Maria De Angelis; Francesco Maria Calabrese; Mauro D'Amato; David Q-H Wang; Agostino Di Ciaula Journal: Biomedicines Date: 2021-12-31
Authors: Agostino Di Ciaula; Jacek Baj; Gabriella Garruti; Giuseppe Celano; Maria De Angelis; Helen H Wang; Domenica Maria Di Palo; Leonilde Bonfrate; David Q-H Wang; Piero Portincasa Journal: J Clin Med Date: 2020-08-14 Impact factor: 4.241