Hepatology Commons^™

Orp2 Regulates Free Cholesterol Accumulation In Hepatocytes During Mash, Jin Wu, Yudi Zhao, Liwen Qiu, Qiaoli Chen, Xiaowei Wang, Jingwen Gu, Yan Liang, Yingjie Zhang, Hong-Yu Wang, Yang Liu, Xiaoqin Wu, Shuai Chen, Feng-Jung Chen, Mingming Gao, Hongyuan Yang

Faculty, Staff and Student Publications

Background: Cholesterol crystals in hepatocytes are known to strongly associate with human metabolic dysfunction-associated steatohepatitis. However, it remains unclear which molecular pathway(s) regulates free cholesterol accumulation and the formation of cholesterol crystals in hepatocytes. In cultured cell lines, oxysterol-binding protein-related protein 2 (ORP2) functions to deliver cholesterol to the plasma membrane from endosomal compartments.

Methods: Here, we generated liver-specific ORP2 knockout (ORP2-LKO) mice and characterized their metabolic phenotypes on chow and high-fat diet.

Results: The ORP2-LKO mice developed much more severe hepatic steatosis than floxed control mice after high-fat diet feeding. They also demonstrated more severe liver inflammation and damage. …

Novel Il-4/Hb-Egf-Dependent Crosstalk Between Eosinophils And Macrophages Controls Liver Regeneration After Ischaemia And Reperfusion Injury, Yang Yang, Long Xu, Constance Atkins, Lily Kuhlman, Jie Zhao, Jong-Min Jeong, Yankai Wen, Nicolas Moreno, Kang Ho Kim, Yu A An, Fenfen Wang, Steve Bynon, Vincenzo Villani, Bin Gao, Frank Brombacher, Raymond Harris, Holger K Eltzschig, Elizabeth Jacobsen, Cynthia Ju

Faculty, Staff and Student Publications

OBJECTIVE: Previous studies indicate that eosinophils are recruited into the allograft following orthotopic liver transplantation and protect from ischaemia reperfusion (IR) injury. In the current studies, we aim to explore whether their protective function could outlast during liver repair.

DESIGN: Eosinophil-deficient mice and adoptive transfer of bone marrow-derived eosinophils (bmEos) were employed to investigate the effects of eosinophils on tissue repair and regeneration after hepatic IR injury. Aside from exogenous cytokine or neutralising antibody treatments, mechanistic studies made use of a panel of mouse models of eosinophil-specific IL-4/IL-13-deletion, cell-specific IL-4rα-deletion in liver macrophages and hepatocytes and macrophage-specific deletion of heparin-binding …

Protection Against Fibrosis By A Bacterial Consortium In Metabolic Dysfunction-Associated Steatohepatitis And The Role Of Amino Acid Metabolism, Suet-Ying Kwan, Kristyn A Gonzales, Mohamed A Jamal, Heather L Stevenson, Lin Tan, Philip L Lorenzi, P Andrew Futreal, Ernest T Hawk, Joseph B Mccormick, Susan P Fisher-Hoch, Robert R Jenq, Laura Beretta

Faculty, Staff and Student Publications

The gut microbiota drives progression to liver fibrosis, the main determinant of mortality in metabolic dysfunction-associated steatohepatitis (MASH). In this study, we aimed to identify bacterial species associated with protection against liver fibrosis in a high-risk population, and test their potential to protect against liver fibrosis in vivo. Based on stool shotgun metagenomic sequencing of 340 subjects from a population cohort disproportionally affected by MASH, we identified bacterial species from the Bacteroidales and Clostridiales orders associated with reduced risk of liver fibrosis. A bacterial consortium was subsequently tested in a mouse model of MASH, which demonstrated protective effects against …

Heterozygous Midnolin Knockout Attenuates Severity Of Nonalcoholic Fatty Liver Disease In Mice Fed A Western-Style Diet High In Fat, Cholesterol, And Fructose, Soo-Mi Kweon, Jose Irimia-Dominguez, Gayeoun Kim, Patrick T Fueger, Kinji Asahina, Keith K Lai, Daniela S Allende, Quincy R Lai, Chih-Hong Lou, Walter M Tsark, Ju Dong Yang, Dominic S Ng, Ju-Seog Lee, Patrick Tso, Wendong Huang, Keane K Y Lai

Faculty, Staff and Student Publications

Although midnolin has been studied for over 20 years, its biological roles in vivo remain largely unknown, especially due to the lack of a functional animal model. Indeed, given our recent discovery that the knockdown of midnolin suppresses liver cancer cell tumorigenicity and that this antitumorigenic effect is associated with modulation of lipid metabolism, we hypothesized that knockout of midnolin in vivo could potentially protect from nonalcoholic fatty liver disease (NAFLD) which has become the most common cause of chronic liver disease in the Western world. Accordingly, in the present study, we have developed and now report on the first …

Interleukin-33 Facilitates Liver Regeneration Through Serotonin-Involved Gut-Liver Axis, Yankai Wen, Christoph Emontzpohl, Long Xu, Constance L Atkins, Jong-Min Jeong, Yang Yang, Kangho Kim, Chuan Wu, Shizuo Akira, Cynthia Ju

Faculty, Staff and Student Publications

BACKGROUND AND AIMS: Insufficient liver regeneration causes post-hepatectomy liver failure and small-for-size syndrome. Identifying therapeutic targets to enhance hepatic regenerative capacity remains urgent. Recently, increased IL-33 was observed in patients undergoing liver resection and in mice after partial hepatectomy (PHx). The present study aims to investigate the role of IL-33 in liver regeneration after PHx and to elucidate its underlying mechanisms.

APPROACH AND RESULTS: We performed PHx in IL-33 -/- , suppression of tumorigenicity 2 (ST2) -/- , and wild-type control mice, and found deficiency of IL-33 or its receptor ST2 delayed liver regeneration. The insufficient liver regeneration could be …

Macrophage-Derived Mlkl In Alcohol-Associated Liver Disease: Regulation Of Phagocytosis, Xiaoqin Wu, Xiude Fan, Megan R Mcmullen, Tatsunori Miyata, Adam Kim, Vai Pathak, Jianguo Wu, Le Z Day, Josiah E Hardesty, Nicole Welch, Jaividhya Dasarathy, Daniela S Allende, Arthur J Mccullough, Jon M Jacobs, Daniel M Rotroff, Srinivasan Dasarathy, Laura E Nagy

Faculty, Staff and Student Publications

BACKGROUND AND AIMS: Mixed lineage kinase domain-like pseudokinase (MLKL), a key terminal effector of necroptosis, also plays a role in intracellular vesicle trafficking that is critical for regulating liver inflammation and injury in alcohol-associated liver disease (ALD). Although receptor interacting protein kinase 3 (Rip3)-/- mice are completely protected from ethanol-induced liver injury, Mlkl-/- mice are only partially protected. Therefore, we hypothesized that cell-specific functions of MLKL may contribute to ethanol-induced injury.

APPROACH AND RESULTS: Bone marrow transplants between Mlkl-/- mice and littermates were conducted to distinguish the role of myeloid versus nonmyeloid Mlkl in the Gao-binge model of ALD. Ethanol-induced …

Eosinophils Protect Against Acetaminophen-Induced Liver Injury Through Cyclooxygenase-Mediated Il-4/Il-13 Production, Long Xu, Yang Yang, Jiali Jiang, Yankai Wen, Jong-Min Jeong, Christoph Emontzpohl, Constance L Atkins, Kangho Kim, Elizabeth A Jacobsen, Hua Wang, Cynthia Ju

Faculty, Staff and Student Publications

BACKGROUND AND AIMS: A better understanding of the underlying mechanism of acetaminophen (APAP)-induced liver injury (AILI) remains an important endeavor to develop therapeutic approaches. Eosinophils have been detected in liver biopsies of patients with APAP overdose. We recently demonstrated a profound protective role of eosinophils against AILI; however, the molecular mechanism had not been elucidated.

APPROACH AND RESULTS: In agreement with our previous data from experiments using genetic deletion of eosinophils, we found that depletion of eosinophils in wild-type (WT) mice by an anti-IL-15 antibody resulted in exacerbated AILI. Moreover, adoptive transfer of eosinophils significantly reduced liver injury and mortality …

Crosstalk Between Beta-Adrenergic And Insulin Signaling Mediates Mechanistic Target Of Rapamycin Hyperactivation In Liver Of High-Fat Diet-Fed Male Mice, Sadia Ashraf, Nadia Ashraf, Gizem Yilmaz, Romain Harmancey

Faculty, Staff and Student Publications

Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease. While increased nutrient intake and sympathetic activity have been associated with the disease, the pathogenesis of NAFLD remains incompletely understood. We investigated the impact of the interaction of high dietary fat and sugar intake with increased beta-adrenergic receptor (β-AR) signaling on the activity of nutrient-sensing pathways and fuel storage in the liver. C57BL/6J mice were fed a standard rodent diet (STD), a high-fat diet (HFD), a high-fat/high-sugar Western diet (WD), a high-sugar diet with mixed carbohydrates (HCD), or a high-sucrose diet (HSD). After 6 week on …

Crosstalk Between Beta-Adrenergic And Insulin Signaling Mediates Mechanistic Target Of Rapamycin Hyperactivation In Liver Of High-Fat Diet-Fed Male Mice, Sadia Ashraf, Nadia Ashraf, Gizem Yilmaz, Romain Harmancey

Faculty, Staff and Student Publications

Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver disease. While increased nutrient intake and sympathetic activity have been associated with the disease, the pathogenesis of NAFLD remains incompletely understood. We investigated the impact of the interaction of high dietary fat and sugar intake with increased beta-adrenergic receptor (β-AR) signaling on the activity of nutrient-sensing pathways and fuel storage in the liver. C57BL/6J mice were fed a standard rodent diet (STD), a high-fat diet (HFD), a high-fat/high-sugar Western diet (WD), a high-sugar diet with mixed carbohydrates (HCD), or a high-sucrose diet (HSD). After 6 week on …

Sirt3 Is Required For Liver Regeneration But Not For The Beneficial Effect Of Nicotinamide Riboside, Sarmistha Mukherjee, James Mo, Lauren M Paolella, Caroline E Perry, Jade Toth, Mindy M Hugo, Qingwei Chu, Qiang Tong, Karthikeyani Chellappa, Joseph A Baur

Children’s Nutrition Research Center Staff Publications

Liver regeneration is critical to survival after traumatic injuries, exposure to hepatotoxins, or surgical interventions, yet the underlying signaling and metabolic pathways remain unclear. In this study, we show that hepatocyte-specific loss of the mitochondrial deacetylase SIRT3 drastically impairs regeneration and worsens mitochondrial function after partial hepatectomy. Sirtuins, including SIRT3, require NAD as a cosubstrate. We previously showed that the NAD precursor nicotinamide riboside (NR) promotes liver regeneration, but whether this involves sirtuins has not been tested. Here, we show that despite their NAD dependence and critical roles in regeneration, neither SIRT3 nor its nuclear counterpart SIRT1 is required for …

Identification Of Novel Regulatory Genes In Apap Induced Hepatocyte Toxicity By A Genome-Wide Crispr-Cas9 Screen., Katherine Shortt, Daniel P. Heruth, Nini Zhang, Weibin Wu, Shipra Singh, Ding-You Li, Li Qin Zhang, Gerald J. Wyckoff, Lei S Qi, Craig A. Friesen, Shui Qing Ye

Manuscripts, Articles, Book Chapters and Other Papers

Acetaminophen (APAP) is a commonly used analgesic responsible for more than half of acute liver failure cases. Identification of previously unknown genetic risk factors would provide mechanistic insights and novel therapeutic targets for APAP-induced liver injury. This study used a genome-wide CRISPR-Cas9 screen to evaluate genes that are protective against, or cause susceptibility to, APAP-induced liver injury. HuH7 human hepatocellular carcinoma cells containing CRISPR-Cas9 gene knockouts were treated with 15 mM APAP for 30 minutes to 4 days. A gene expression profile was developed based on the 1) top screening hits, 2) overlap of expression data from APAP overdose studies, …

Complement Factor D Protects Mice From Ethanol-Induced Inflammation And Liver Injury., Rebecca L Mccullough, Megan R Mcmullen, Megan M Sheehan, Kyle L Poulsen, Sanjoy Roychowdhury, Dian J Chiang, Michele T Pritchard, Juan Caballeria, Laura E Nagy

Articles, Abstracts, and Reports

Complement plays a crucial role in microbial defense and clearance of apoptotic cells. Emerging evidence suggests complement is an important contributor to alcoholic liver disease. While complement component 1, Q subcomponent (C1q)-dependent complement activation contributes to ethanol-induced liver injury, the role of the alternative pathway in ethanol-induced injury is unknown. Activation of complement via the classical and alternative pathways was detected in alcoholic hepatitis patients. Female C57BL/6J [wild type (WT)], C1q-deficient ( C1qa