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Chopyk DM, Dedhia PH. Pandemic impact: Decline in endocrine operations hits vulnerable populations harder. Am J Surg 2024; 228:20-21. [PMID: 37806891 DOI: 10.1016/j.amjsurg.2023.10.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2023] [Revised: 10/02/2023] [Accepted: 10/02/2023] [Indexed: 10/10/2023]
Affiliation(s)
- Daniel M Chopyk
- Department of Surgery, The Ohio State University Wexner Medical Center and James Cancer Hospital and Solove Research Institute, 395 W. 12Th Avenue, Suite 670, Columbus, OH, USA
| | - Priya H Dedhia
- Division of Surgical Oncology, The Ohio State University and Arthur G. James Comprehensive Cancer Center, Columbus, OH, USA; Translational Therapeutics Program, The Ohio State University and Arthur G. James Comprehensive Cancer Center, Columbus, OH, USA.
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2
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Thapa M, Kumari A, Chin CY, Choby JE, Jin F, Bogati B, Chopyk DM, Koduri N, Pahnke A, Elrod EJ, Burd EM, Weiss DS, Grakoui A. Translocation of gut commensal bacteria to the brain. bioRxiv 2023:2023.08.30.555630. [PMID: 37693595 PMCID: PMC10491268 DOI: 10.1101/2023.08.30.555630] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/12/2023]
Abstract
The gut-brain axis, a bidirectional signaling network between the intestine and the central nervous system, is crucial to the regulation of host physiology and inflammation. Recent advances suggest a strong correlation between gut dysbiosis and neurological diseases, however, relatively little is known about how gut bacteria impact the brain. Here, we reveal that gut commensal bacteria can translocate directly to the brain when mice are fed an altered diet that causes dysbiosis and intestinal permeability, and that this also occurs without diet alteration in distinct murine models of neurological disease. The bacteria were not found in other systemic sites or the blood, but were detected in the vagus nerve. Unilateral cervical vagotomy significantly reduced the number of bacteria in the brain, implicating the vagus nerve as a conduit for translocation. The presence of bacteria in the brain correlated with microglial activation, a marker of neuroinflammation, and with neural protein aggregation, a hallmark of several neurodegenerative diseases. In at least one model, the presence of bacteria in the brain was reversible as a switch from high-fat to standard diet resulted in amelioration of intestinal permeability, led to a gradual loss of detectable bacteria in the brain, and reduced the number of neural protein aggregates. Further, in murine models of Alzheimer's disease, Parkinson's disease, and autism spectrum disorder, we observed gut dysbiosis, gut leakiness, bacterial translocation to the brain, and microglial activation. These data reveal a commensal bacterial translocation axis to the brain in models of diverse neurological diseases.
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Affiliation(s)
- Manoj Thapa
- Emory Vaccine Center, Division of Microbiology and Immunology, Emory National Primate Research Center, Emory University, Atlanta, Georgia
| | - Anuradha Kumari
- Emory Vaccine Center, Division of Microbiology and Immunology, Emory National Primate Research Center, Emory University, Atlanta, Georgia
| | - Chui-Yoke Chin
- Emory Vaccine Center, Division of Microbiology and Immunology, Emory National Primate Research Center, Emory University, Atlanta, Georgia
| | - Jacob E. Choby
- Emory Vaccine Center, Division of Microbiology and Immunology, Emory National Primate Research Center, Emory University, Atlanta, Georgia
| | - Fengzhi Jin
- Emory Vaccine Center, Division of Microbiology and Immunology, Emory National Primate Research Center, Emory University, Atlanta, Georgia
| | - Bikash Bogati
- Emory Vaccine Center, Division of Microbiology and Immunology, Emory National Primate Research Center, Emory University, Atlanta, Georgia
| | - Daniel M. Chopyk
- Emory Vaccine Center, Division of Microbiology and Immunology, Emory National Primate Research Center, Emory University, Atlanta, Georgia
| | - Nitya Koduri
- Emory Vaccine Center, Division of Microbiology and Immunology, Emory National Primate Research Center, Emory University, Atlanta, Georgia
| | - Andrew Pahnke
- Emory Vaccine Center, Division of Microbiology and Immunology, Emory National Primate Research Center, Emory University, Atlanta, Georgia
| | - Elizabeth J. Elrod
- Emory Vaccine Center, Division of Microbiology and Immunology, Emory National Primate Research Center, Emory University, Atlanta, Georgia
| | - Eileen M. Burd
- Division of Infectious Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia
- Emory Antibiotic Resistance Center, Emory University School of Medicine, Atlanta, Georgia
- Department of Pathology and Laboratory Medicine, Emory University, Atlanta, Georgia
| | - David S. Weiss
- Emory Vaccine Center, Division of Microbiology and Immunology, Emory National Primate Research Center, Emory University, Atlanta, Georgia
- Division of Infectious Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia
- Emory Antibiotic Resistance Center, Emory University School of Medicine, Atlanta, Georgia
| | - Arash Grakoui
- Emory Vaccine Center, Division of Microbiology and Immunology, Emory National Primate Research Center, Emory University, Atlanta, Georgia
- Division of Infectious Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia
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Chopyk DM, Grakoui A. Contribution of the Intestinal Microbiome and Gut Barrier to Hepatic Disorders. Gastroenterology 2020; 159:849-863. [PMID: 32569766 PMCID: PMC7502510 DOI: 10.1053/j.gastro.2020.04.077] [Citation(s) in RCA: 192] [Impact Index Per Article: 48.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/06/2020] [Revised: 04/16/2020] [Accepted: 04/29/2020] [Indexed: 02/07/2023]
Abstract
Intestinal barrier dysfunction and dysbiosis contribute to development of diseases in liver and other organs. Physical, immunologic, and microbiologic (bacterial, fungal, archaeal, viral, and protozoal) features of the intestine separate its nearly 100 trillion microbes from the rest of the human body. Failure of any aspect of this barrier can result in translocation of microbes into the blood and sustained inflammatory response that promote liver injury, fibrosis, cirrhosis, and oncogenic transformation. Alterations in intestinal microbial populations or their functions can also affect health. We review the mechanisms that regulate intestinal permeability and how changes in the intestinal microbiome contribute to development of acute and chronic liver diseases. We discuss individual components of the intestinal barrier and how these are disrupted during development of different liver diseases. Learning more about these processes will increase our understanding of the interactions among the liver, intestine, and its flora.
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Affiliation(s)
- Daniel M. Chopyk
- Emory Vaccine Center, Division of Microbiology and Immunology, Yerkes National Primate Research Center, Emory University School of Medicine, Atlanta, GA
| | - Arash Grakoui
- Emory Vaccine Center, Division of Microbiology and Immunology, Yerkes National Primate Research Center, Emory University School of Medicine, Atlanta, Georgia; Division of Infectious Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia.
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Pearson L, Chopyk DM, Rosen SA. Case report of surgical management of a locally invasive colostomy adenocarcinoma. Int J Surg Case Rep 2020; 72:603-607. [PMID: 32698298 PMCID: PMC7332502 DOI: 10.1016/j.ijscr.2020.06.064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Accepted: 06/15/2020] [Indexed: 02/07/2023] Open
Abstract
INTRODUCTION This case report involves the presentation and management of a locally invasive adenocarcinoma at the site of a colostomy in a patient with multiple comorbidities and anatomic constraints. PRESENTATION OF CASE 63 year-old woman with a complicated medical and surgical history, including imperforate anus and permanent colostomy, who presented with a fungating mass at the site of her colostomy. Evaluation revealed a locally invasive adenocarcinoma requiring surgical management for symptom control and oncologic treatment. DISCUSSION Due to the patient's medical comorbidities, body habitus, prior surgery, prior radiation and locally invasive cancer, there were numerous physiologic and anatomic issues that required a multi-disciplinary approach. Specifically, consideration of the patient's prior radiation to the left chest, history of cystectomy and ileal conduit, history of prior colon resection, as well as her short stature and severe kyphosis required input from urology, plastic surgery and colorectal surgery for operative planning. The patient's chronic renal insufficiency, recurrent urinary tract infections and history of thromboembolic disease further complicated her perioperative management. Oncologic resection with wide local excision at the skin and abdominal wall were performed with mass closure of the midline and peristomal abdominoplasty, using mesh underlay. The patient's postoperative course was complicated by gastric outlet obstruction and recurrent urosepsis. CONCLUSIONS Patients with chronic colostomies require colon cancer screening similar to their non-stoma peers, in accordance with national guidelines. Oncologic resection of cancers involving colostomies is feasible, but may require multi-disciplinary planning to manage complicated anatomic concerns.
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Affiliation(s)
- Lindsay Pearson
- Division of Colorectal Surgery, Department of Surgery, Emory University School of Medicine, Room B206, 1364 Clifton Road, NE, Atlanta, GA 30322, United States
| | - Daniel M Chopyk
- Emory University School of Medicine, James B Williams Medical Education Bldg, 100 Woodruff Circle, Atlanta, GA 30322, United States
| | - Seth A Rosen
- Division of Colorectal Surgery, Department of Surgery, Emory University School of Medicine, Room B206, 1364 Clifton Road, NE, Atlanta, GA 30322, United States.
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Gupta B, Liu Y, Chopyk DM, Rai RP, Desai C, Kumar P, Farris AB, Nusrat A, Parkos CA, Anania FA, Raeman R. Western diet-induced increase in colonic bile acids compromises epithelial barrier in nonalcoholic steatohepatitis. FASEB J 2020; 34:7089-7102. [PMID: 32275114 DOI: 10.1096/fj.201902687r] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2019] [Revised: 02/24/2020] [Accepted: 03/19/2020] [Indexed: 12/13/2022]
Abstract
There is compelling evidence implicating intestinal permeability in the pathogenesis of nonalcoholic steatohepatitis (NASH), but the underlying mechanisms remain poorly understood. Here we examined the role of bile acids (BA) in western diet (WD)-induced loss of colonic epithelial barrier (CEB) function in mice with a genetic impairment in intestinal epithelial barrier function, junctional adhesion molecule A knockout mice, F11r-/- . WD-fed knockout mice developed severe NASH, which was associated with increased BA concentration in the cecum and loss of CEB function. Analysis of cecal BA composition revealed selective increases in primary unconjugated BAs in the WD-fed mice, which correlated with increased abundance of microbial taxa linked to BA metabolism. In vitro permeability assays revealed that chenodeoxycholic acid (CDCA), which was elevated in the cecum of WD-fed mice, increased paracellular permeability, while the BA-binding resin sevelamer hydrochloride protected against CDCA-induced loss of barrier function. Sequestration of intestinal BAs by in vivo delivery of sevelamer to WD-fed knockout mice attenuated colonic mucosal inflammation and improved CEB. Sevelamer also reduced hepatic inflammation and fibrosis, and improved metabolic derangements associated with NASH. Collectively, these findings highlight a hitherto unappreciated role for BAs in WD-induced impairment of the intestinal epithelial barrier in NASH.
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Affiliation(s)
- Biki Gupta
- Division of Experimental Pathology, Department of Pathology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Yunshan Liu
- Division of Digestive Diseases, Department of Medicine, Emory University, Atlanta, GA, USA
| | - Daniel M Chopyk
- Division of Digestive Diseases, Department of Medicine, Emory University, Atlanta, GA, USA
| | - Ravi P Rai
- Division of Experimental Pathology, Department of Pathology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Chirayu Desai
- Department of Microbiology and Immunology, P. D. Patel Institute of Applied Sciences, Charotar University of Science and Technology, Gujarat, India
| | - Pradeep Kumar
- Division of Digestive Diseases, Department of Medicine, Emory University, Atlanta, GA, USA
| | - Alton B Farris
- Department of Pathology and Laboratory Medicine, Emory University, Atlanta, GA, USA
| | - Asma Nusrat
- Department of Pathology, University of Michigan, Ann Arbor, MI, USA
| | - Charles A Parkos
- Department of Pathology, University of Michigan, Ann Arbor, MI, USA
| | - Frank A Anania
- Division of Gastroenterology and Inborn Error Products, Food and Drug Administration, Silver Spring, MD, USA
| | - Reben Raeman
- Division of Experimental Pathology, Department of Pathology, University of Pittsburgh, Pittsburgh, PA, USA.,Pittsburgh Liver Research Center, University of Pittsburgh Medical Center, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
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Chopyk DM, Stuart JD, Zimmerman MG, Wen J, Gumber S, Suthar MS, Thapa M, Czaja MJ, Grakoui A. Acetaminophen Intoxication Rapidly Induces Apoptosis of Intestinal Crypt Stem Cells and Enhances Intestinal Permeability. Hepatol Commun 2019; 3:1435-1449. [PMID: 31701068 PMCID: PMC6824060 DOI: 10.1002/hep4.1406] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Accepted: 06/24/2019] [Indexed: 12/16/2022] Open
Abstract
Acetaminophen (APAP)‐induced liver injury is the most common cause of acute liver failure (ALF) in the Western world. APAP toxicity progresses to multiorgan dysfunction and thus has broader whole‐body implications. Importantly, greater 30‐day mortality has been observed in liver transplant recipients following ALF due to APAP‐related versus non‐APAP‐related causes. Reasons for this discrepancy have yet to be determined. Extrahepatic toxicities of APAP overdose may represent underappreciated and unaddressed comorbidities within this patient population. In the present study, rapid induction of apoptosis following APAP overdose was observed in the intestine, an organ that greatly influences the physiology of the liver. Strikingly, apoptotic cells appeared to be strictly restricted to the intestinal crypts. The use of leucine‐rich repeat‐containing G protein–coupled receptor 5 (LGR5) reporter mice confirmed that the LGR5‐positive (+) crypt base stem cells were disproportionately affected by APAP‐induced cell death. Although the apoptotic cells were cleared within 24 hours after APAP treatment, potentially long‐lived consequences on the intestine due to APAP exposure were indicated by prolonged deficits in gut barrier function. Moreover, small intestinal cell death was found to be independent of tumor necrosis factor receptor signaling and may represent a direct toxic insult to the intestine by exposure to high concentrations of APAP. Conclusion: APAP induces intestinal injury through a regulated process of apoptotic cell death that disproportionately affects LGR5+ stem cells. This work advances our understanding of the consequences of APAP toxicity in a novel organ that was not previously considered as a significant site of injury and thus presents potential new considerations for patient management.
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Affiliation(s)
- Daniel M Chopyk
- Emory Vaccine Center, Division of Microbiology and Immunology Yerkes National Primate Research Center, Emory University School of Medicine Atlanta GA
| | - Johnasha D Stuart
- Emory Vaccine Center, Division of Microbiology and Immunology Yerkes National Primate Research Center, Emory University School of Medicine Atlanta GA
| | - Matthew G Zimmerman
- Division of Infectious Diseases, Department of Pediatrics Emory University School of Medicine Atlanta GA.,Emory Vaccine Center Yerkes National Primate Research Center, Emory University School of Medicine Atlanta GA
| | - Jing Wen
- Division of Digestive Diseases, Department of Medicine Emory University School of Medicine Atlanta GA
| | - Sanjeev Gumber
- Division of Pathology and Laboratory Medicine Yerkes National Primate Research Center, Emory University School of Medicine Atlanta GA
| | - Mehul S Suthar
- Division of Infectious Diseases, Department of Pediatrics Emory University School of Medicine Atlanta GA.,Emory Vaccine Center Yerkes National Primate Research Center, Emory University School of Medicine Atlanta GA
| | - Manoj Thapa
- Emory Vaccine Center, Division of Microbiology and Immunology Yerkes National Primate Research Center, Emory University School of Medicine Atlanta GA
| | - Mark J Czaja
- Division of Digestive Diseases, Department of Medicine Emory University School of Medicine Atlanta GA
| | - Arash Grakoui
- Emory Vaccine Center, Division of Microbiology and Immunology Yerkes National Primate Research Center, Emory University School of Medicine Atlanta GA.,Division of Infectious Diseases, Department of Medicine Emory University School of Medicine Atlanta GA
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Forrest OA, Chopyk DM, Gernez Y, Brown MR, Conrad CK, Moss RB, Tangpricha V, Peng L, Tirouvanziam R. Resistin is elevated in cystic fibrosis sputum and correlates negatively with lung function. J Cyst Fibros 2019; 18:64-70. [DOI: 10.1016/j.jcf.2018.05.018] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2018] [Revised: 05/30/2018] [Accepted: 05/31/2018] [Indexed: 01/04/2023]
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8
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Kumar P, Raeman R, Chopyk DM, Smith T, Verma K, Liu Y, Anania FA. Adiponectin inhibits hepatic stellate cell activation by targeting the PTEN/AKT pathway. Biochim Biophys Acta Mol Basis Dis 2018; 1864:3537-3545. [PMID: 30293572 PMCID: PMC6529190 DOI: 10.1016/j.bbadis.2018.08.012] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Revised: 08/05/2018] [Accepted: 08/07/2018] [Indexed: 02/08/2023]
Abstract
Adiponectin inhibits hepatic stellate cell (HSC) activation and subsequent development of liver fibrosis via multiple mechanisms. Phosphatase and tensin homolog deletion 10 (PTEN) plays a crucial role in suppression of HSC activation, but its regulation by adiponectin is not fully understood. Here, we investigated the effect of adiponectin on PTEN in LX-2 cells, a human cell line and examined the underlying molecular mechanisms involved in adiponectin-mediated upregulation of PTEN activity during fibrosis. PTEN expression was found to be significantly reduced in the livers of mice treated with CCl4, whereas its expression was rescued by adiponectin treatment. The DNA methylation proteins DNMT1, DNMT3A, and DNMT3B are all highly expressed in activated primary HSCs compared to quiescent HSCs, and thus represent additional regulatory targets during liver fibrogenesis. Expression of DNMT proteins was significantly induced in the presence of fibrotic stimuli; however, only DNMT3B expression was reduced in the presence of adiponectin. Adiponectin-induced suppression of DNMT3B was found to be mediated by enhanced miR-29b expression. Furthermore, PTEN expression was significantly increased by overexpression of miR-29b, whereas its expression was markedly reduced by a miR-29b inhibitor in LX-2 cells. These findings suggest that adiponectin-induced upregulation of miR-29b can suppress DNMT3B transcription in LX-2 cells, thus resulting in reduced methylation of PTEN CpG islands and ultimately suppressing the PI3K/AKT pathway. Together, these data suggest a possible new explanation for the inhibitory effect of adiponectin on HSC activation and liver fibrogenesis.
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Affiliation(s)
- Pradeep Kumar
- Division of Digestive Diseases, Department of Medicine, Emory University, Atlanta, GA, USA.
| | - Reben Raeman
- Department of Pathology, University of Pittsburgh, Pittsburgh, PA, USA
| | - Daniel M Chopyk
- Division of Digestive Diseases, Department of Medicine, Emory University, Atlanta, GA, USA
| | - Tekla Smith
- Division of Digestive Diseases, Department of Medicine, Emory University, Atlanta, GA, USA
| | - Kiran Verma
- Labratory of Biochemical Pharmacology, Department of Pediatrics, Emory University, Atlanta, GA, USA
| | - Yunshan Liu
- Division of Digestive Diseases, Department of Medicine, Emory University, Atlanta, GA, USA
| | - Frank A Anania
- Division of Digestive Diseases, Department of Medicine, Emory University, Atlanta, GA, USA
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Chopyk DM, Kumar P, Raeman R, Liu Y, Smith T, Anania FA. Dysregulation of junctional adhesion molecule-A contributes to ethanol-induced barrier disruption in intestinal epithelial cell monolayers. Physiol Rep 2018; 5. [PMID: 29208693 PMCID: PMC5727288 DOI: 10.14814/phy2.13541] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Accepted: 11/05/2017] [Indexed: 12/15/2022] Open
Abstract
Alcohol consumption promotes loss of intestinal barrier function. However, mechanisms by which ethanol affects the tight junction (TJ), the cellular structure responsible for maintaining the gut epithelial barrier, are not well understood. Three classes of transmembrane proteins comprise TJs: occludin, claudins, and junctional adhesion molecules (JAMs). It has recently been postulated that JAM‐A (F11R), the most abundant JAM expressed in intestinal epithelium, regulates “leak” pathway flux, a paracellular route for the nonselective permeation of large solutes. Since transluminal flux of many gut‐derived antigens occurs through this pathway, we investigated the role of JAM‐A in ethanol‐induced disruption of the intestinal epithelial barrier. Using Caco‐2 and SK‐CO15 monolayers, we found that ethanol induced a dose‐ and time‐dependent decrease in JAM‐A protein expression to about 70% of baseline levels. Alcohol also reduced Ras‐related protein 2 (Rap2) activity, and enhanced myosin light chain kinase (MLCK) activity, changes consistent with impaired JAM‐A signaling. Stable overexpression and shRNA‐mediated knockdown of JAM‐A were employed to investigate the role of JAM‐A in paracellular‐mediated flux following alcohol exposure. The paracellular flux of 40‐kDa fluorescein isothiocynate (FITC)‐dextran following ethanol treatment was decreased by the overexpression of JAM‐A; conversely, flux was enhanced by JAM‐A knockdown. Thus, we conclude that ethanol‐mediated control of JAM‐A expression and function contributes to mechanisms by which this chemical induces intestinal epithelial leakiness.
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Affiliation(s)
- Daniel M Chopyk
- Division of Digestive Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia
| | - Pradeep Kumar
- Division of Digestive Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia
| | - Reben Raeman
- Division of Digestive Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia
| | - Yunshan Liu
- Division of Digestive Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia
| | - Tekla Smith
- Division of Digestive Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia
| | - Frank A Anania
- Division of Digestive Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia
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Kumar P, Smith T, Raeman R, Chopyk DM, Brink H, Liu Y, Sulchek T, Anania FA. Periostin promotes liver fibrogenesis by activating lysyl oxidase in hepatic stellate cells. J Biol Chem 2018; 293:12781-12792. [PMID: 29941453 DOI: 10.1074/jbc.ra117.001601] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Revised: 06/20/2018] [Indexed: 12/29/2022] Open
Abstract
Liver fibrosis arises from dysregulated wound healing due to persistent inflammatory hepatic injury. Periostin is a nonstructural extracellular matrix protein that promotes organ fibrosis in adults. Here, we sought to identify the molecular mechanisms in periostin-mediated hepatic fibrosis. Hepatic fibrosis in periostin-/- mice was attenuated as evidenced by significantly reduced collagen fibril density and liver stiffness compared with those in WT controls. A single dose of carbon tetrachloride caused similar acute liver injury in periostin-/- and WT littermates, and we did not detect significant differences in transaminases and major fibrosis-related hepatic gene expression between these two genotypes. Activated hepatic stellate cells (HSCs) are the major periostin-producing liver cell type. We found that in primary rat HSCs in vitro, periostin significantly increases the expression levels and activities of lysyl oxidase (LOX) and lysyl oxidase-like (LOXL) isoforms 1-3. Periostin also induced expression of intra- and extracellular collagen type 1 and fibronectin in HSCs. Interestingly, periostin stimulated phosphorylation of SMAD2/3, which was sustained despite short hairpin RNA-mediated knockdown of transforming growth factor β (TGFβ) receptor I and II, indicating that periostin-mediated SMAD2/3 phosphorylation is independent of TGFβ receptors. Moreover, periostin induced the phosphorylation of focal adhesion kinase (FAK) and AKT in HSCs. Notably, siRNA-mediated FAK knockdown failed to block periostin-induced SMAD2/3 phosphorylation. These results suggest that periostin promotes enhanced matrix stiffness in chronic liver disease by activating LOX and LOXL, independently of TGFβ receptors. Hence, targeting periostin may be of therapeutic benefit in combating hepatic fibrosis.
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Affiliation(s)
- Pradeep Kumar
- Division of Digestive Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia 30322.
| | - Tekla Smith
- Division of Digestive Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia 30322
| | - Reben Raeman
- Department of Pathology, University of Pittsburgh, Pittsburgh, Pennsylvania 15261
| | - Daniel M Chopyk
- Division of Digestive Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia 30322
| | - Hannah Brink
- Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332
| | - Yunshan Liu
- Division of Digestive Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia 30322
| | - Todd Sulchek
- Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332
| | - Frank A Anania
- Division of Digestive Diseases, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia 30322
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11
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Chopyk DM, Robinson J, Trueblood K, Dubyak GR. Expression of P2X7 receptor splice variants is differentially regulated in macrophages versus T lymphocytes and is modulated by inflammatory cytokines. FASEB J 2011. [DOI: 10.1096/fasebj.25.1_supplement.562.3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Daniel M Chopyk
- Physiology and BiophysicsCase Western Reserve UniversityClevelandOH
| | - Jason Robinson
- Physiology and BiophysicsCase Western Reserve UniversityClevelandOH
| | | | - George R Dubyak
- Physiology and BiophysicsCase Western Reserve UniversityClevelandOH
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