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Kakimoto T, Hosokawa M, Ichimura-Shimizu M, Ogawa H, Miyakami Y, Sumida S, Tsuneyama K. Accumulation of α-synuclein in hepatocytes in nonalcoholic steatohepatitis and its usefulness in pathological diagnosis. Pathol Res Pract 2023; 247:154525. [PMID: 37209576 DOI: 10.1016/j.prp.2023.154525] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2023] [Revised: 05/04/2023] [Accepted: 05/08/2023] [Indexed: 05/22/2023]
Abstract
BACKGROUNDS Nonalcoholic steatohepatitis (NASH) is characterized by fat deposition, inflammation, and hepatocellular damage. The diagnosis of NASH is confirmed pathologically, and hepatocyte ballooning is an important finding for definite diagnosis. Recently, α-synuclein deposition in multiple organs was reported in Parkinson's disease. Since it was reported that α-synuclein is taken up by hepatocytes via connexin 32, the expression of α-synuclein in the liver in NASH is of interest. The accumulation of α-synuclein in the liver in NASH was investigated. Immunostaining for p62, ubiquitin, and α-synuclein was performed, and the usefulness of immunostaining in pathological diagnosis was examined. METHODS Liver biopsy tissue specimens from 20 patients were evaluated. Several antibodies against α-synuclein, as well as antibodies against connexin 32, p62, and ubiquitin were used for immunohistochemical analyses. Staining results were evaluated by several pathologists with varying experience, and the diagnostic accuracy of ballooning was compared. RESULTS Polyclonal α-synuclein antibody, not the monoclonal antibody, reacted with eosinophilic aggregates in ballooning cells. Expression of connexin 32 in degenerating cells was also demonstrated. Antibodies against p62 and ubiquitin also reacted with some of the ballooning cells. In the pathologists' evaluations, the highest interobserver agreement was obtained with hematoxylin and eosin (H&E)-stained slides, followed by slides immunostained for p62 and α-synuclein, and there were cases with different results between H&E staining and immunostaining CONCLUSION: These results indicate the incorporation of degenerated α-synuclein into ballooning cells, suggesting the involvement of α-synuclein in the pathogenesis of NASH. The combination of immunostaining including polyclonal α-synuclein may contribute to improving the diagnosis of NASH.
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Affiliation(s)
- Takumi Kakimoto
- Department of Pathology and Laboratory Medicine, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan; Department of Pathology, Tokushima University Hospital, Tokushima, Japan
| | - Masato Hosokawa
- Department of Immunological and Molecular Pharmacology, Fukuoka University Faculty of Pharmaceutical Sciences, Fukuoka, Japan
| | - Mayuko Ichimura-Shimizu
- Department of Pathology and Laboratory Medicine, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan
| | - Hirohisa Ogawa
- Department of Pathology and Laboratory Medicine, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan
| | - Yuko Miyakami
- Department of Pathology and Laboratory Medicine, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan; Department of Pathology, Tokushima University Hospital, Tokushima, Japan
| | - Satoshi Sumida
- Department of Pathology and Laboratory Medicine, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan; Department of Pathology, Tokushima University Hospital, Tokushima, Japan
| | - Koichi Tsuneyama
- Department of Pathology and Laboratory Medicine, Institute of Biomedical Sciences, Tokushima University Graduate School, Tokushima, Japan.
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Mizdrak I, Mizdrak M, Racetin A, Bošković B, Benzon B, Durdov MG, Vukojević K, Filipović N. Expression of Connexins 37, 40 and 45, Pannexin 1 and Vimentin in Laryngeal Squamous Cell Carcinomas. Genes (Basel) 2023; 14:446. [PMID: 36833374 PMCID: PMC9956287 DOI: 10.3390/genes14020446] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Revised: 02/03/2023] [Accepted: 02/06/2023] [Indexed: 02/12/2023] Open
Abstract
Approximately 60% of patients with squamous cell carcinoma (LSCC) have regional occult metastatic disease/distant metastases at the time of diagnosis, putting them at higher risk for disease progression. Therefore, biomarkers are needed for early prognostic purpose. The aim of this study was to analyze the expression pattern of connexins (Cx) 37, 40 and 45, pannexin1 (Panx1) and vimentin in LSCC and correlate with tumor grade (G) and outcome. METHODS Thirty-four patients who underwent (hemi-)laryngectomy and regional lymphadenectomy due to LSCC from 2017 to 2018 in University Hospital Split, Croatia, were studied. Samples of tumor tissue and adjacent normal mucosa embedded in paraffin blocks were stained using the immunofluorescence method and were semi-quantitatively analyzed. RESULTS The expression of Cx37, Cx40, and Panx1 differed between cancer and adjacent normal mucosa and between histological grades, being the highest in well-differentiated (G1) cancer and low/absent in poorly differentiated (G3) cancer (all p < 0.05). The expression of vimentin was the highest in G3 cancer. Expression of Cx45 was generally weak/absent, with no significant difference between cancer and the controls or between grades. Lower Panx1 and higher vimentin expression were found to be prognostic factors for regional metastatic disease. Lower Cx37 and 40 expressions were present in patients with disease recurrence after the three-year follow-up period. CONCLUSION Cx37 and Cx40, Panx1, and vimentin have the potential to be used as prognostic biomarkers for LSCC.
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Affiliation(s)
- Ivan Mizdrak
- Department of Otorhinolaryngology, Head and Neck Surgery, University Hospital of Split, Spinčićeva 1, 21000 Split, Croatia
| | - Maja Mizdrak
- Department of Nephrology and Hemodialysis, University Hospital of Split, Šoltanska 1, 21000 Split, Croatia
| | - Anita Racetin
- Department of Anatomy, Histology and Embryology, University of Split School of Medicine, Šoltanska 2, 21000 Split, Croatia
| | - Braco Bošković
- Department of Otorhinolaryngology, Head and Neck Surgery, University Hospital of Split, Spinčićeva 1, 21000 Split, Croatia
| | - Benjamin Benzon
- Department of Anatomy, Histology and Embryology, University of Split School of Medicine, Šoltanska 2, 21000 Split, Croatia
| | - Merica Glavina Durdov
- Department of Pathology, Forensic Medicine and Cytology, University Hospital of Split, University of Split School of Medicine, Spinčićeva 1, 21000 Split, Croatia
| | - Katarina Vukojević
- Department of Anatomy, Histology and Embryology, University of Split School of Medicine, Šoltanska 2, 21000 Split, Croatia
| | - Natalija Filipović
- Department of Anatomy, Histology and Embryology, University of Split School of Medicine, Šoltanska 2, 21000 Split, Croatia
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Yu F, Yan L, Sun J, Zhao Y, Yuan Y, Gu J, Bian J, Zou H, Liu Z. Gap junction intercellular communication mediates cadmium-induced apoptosis in hepatocytes via the Fas/FasL pathway. ENVIRONMENTAL TOXICOLOGY 2022; 37:2692-2702. [PMID: 35920667 DOI: 10.1002/tox.23629] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Revised: 07/14/2022] [Accepted: 07/15/2022] [Indexed: 06/15/2023]
Abstract
As a common environmental pollutant, cadmium (Cd) causes damage to many organs of the body. Gap junction intercellular communication (GJIC) represents one of the most important routes of rapid signaling between cells. However, the mechanisms underlying GJIC's role in hepatotoxicity induced by Cd remain unknown. We established a Cd poisoning model in vitro by co-culturing Cd-exposed and unexposed hepatocytes and found that 18β-glycyrrhetinic acid (GA), a GJIC inhibitor, can effectively reduce the apoptosis rate of healthy cells co-cultured with apoptotic cells treated with Cd. We also found that anti-FasL antibody had the same effect. However, in mono-cultured cells, GA treatment in combination with Cd was found to aggravate the damage induced by Cd exposure, increase the level of oxidative stress and protein expression of HO-1, decrease the mitochondrial membrane potential, incur more serious morphological damage to mitochondria than Cd treatment alone. Moreover, compared with Cd-only exposure, GA and Cd co-treatment further increased the expression levels of the apoptosis-related proteins Fas, FasL, FADD and the ratio of Bax/Bcl-2, inhibited the protein expression of ASK1 and Daxx. We also found that the protein expression of Daxx in siFADD + Cd hepatocytes was significantly higher than in Cd-treated cells. Thus, our study suggests that gap junction inhibition may play a dual role in Cd-induced cell damage by inhibiting the transmission of death signals from damaged cells to healthy cells but also aggravating the transmission of death signals between damaged cells, and that the Fas/FasL-mediated death receptor pathway may play an important role in this process.
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Affiliation(s)
- Fan Yu
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, People's Republic of China
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, School of Horticulture and Plant Protection, Yangzhou University, Yangzhou, Jiangsu, People's Republic of China
- Jiangsu Coinnovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, People's Republic of China
| | - Lianqi Yan
- Department of Orthopedics, The Second Xiangya Hospital of Central South University, Changsha, Hunan, People's Republic of China
- Department of Orthopedics, Clinical Medical College of Yangzhou University, Subei People's Hospital, Yangzhou, Jiangsu, People's Republic of China
| | - Jian Sun
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, People's Republic of China
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, School of Horticulture and Plant Protection, Yangzhou University, Yangzhou, Jiangsu, People's Republic of China
- Jiangsu Coinnovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, People's Republic of China
| | - Yumeng Zhao
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, People's Republic of China
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, School of Horticulture and Plant Protection, Yangzhou University, Yangzhou, Jiangsu, People's Republic of China
- Jiangsu Coinnovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, People's Republic of China
| | - Yan Yuan
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, People's Republic of China
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, School of Horticulture and Plant Protection, Yangzhou University, Yangzhou, Jiangsu, People's Republic of China
- Jiangsu Coinnovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, People's Republic of China
| | - Jianhong Gu
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, People's Republic of China
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, School of Horticulture and Plant Protection, Yangzhou University, Yangzhou, Jiangsu, People's Republic of China
- Jiangsu Coinnovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, People's Republic of China
| | - Jianchun Bian
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, People's Republic of China
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, School of Horticulture and Plant Protection, Yangzhou University, Yangzhou, Jiangsu, People's Republic of China
- Jiangsu Coinnovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, People's Republic of China
| | - Hui Zou
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, People's Republic of China
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, School of Horticulture and Plant Protection, Yangzhou University, Yangzhou, Jiangsu, People's Republic of China
- Jiangsu Coinnovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, People's Republic of China
| | - Zongping Liu
- College of Veterinary Medicine, Yangzhou University, Yangzhou, Jiangsu, People's Republic of China
- Joint International Research Laboratory of Agriculture and Agri-Product Safety, School of Horticulture and Plant Protection, Yangzhou University, Yangzhou, Jiangsu, People's Republic of China
- Jiangsu Coinnovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu, People's Republic of China
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Intercellular communication in the tumour microecosystem: Mediators and therapeutic approaches for hepatocellular carcinoma. Biochim Biophys Acta Mol Basis Dis 2022; 1868:166528. [PMID: 36007784 DOI: 10.1016/j.bbadis.2022.166528] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2022] [Revised: 08/10/2022] [Accepted: 08/18/2022] [Indexed: 11/24/2022]
Abstract
Hepatocellular carcinoma (HCC), one of the most common tumours worldwide, is one of the main causes of mortality in cancer patients. There are still numerous problems hindering its early diagnosis, which lead to late patients receiving treatment, and these problems need to be solved urgently. The tumour microecosystem is a complex network system comprising seven parts: the hypoxia niche, immune microenvironment, metabolic microenvironment, acidic niche, innervated niche, mechanical microenvironment, and microbial microenvironment. Intercellular communication is divided into direct contact and indirect communication. Direct contact communication includes gap junctions, tunneling nanotubes, and receptor-ligand interactions, whereas indirect communication includes exosomes, apoptotic vesicles, and soluble factors. Mechanical communication and cytoplasmic exchange are further means of intercellular communication. Intercellular communication mediates the crosstalk between the tumour microecosystem and the host as well as that between cells and cell-free components in the tumour microecosystem, causing changes in the tumour hallmarks of the HCC microecosystem such as changes in tumour proliferation, invasion, apoptosis, angiogenesis, metastasis, inflammatory response, gene mutation, immune escape, metabolic reprogramming, and therapeutic resistance. Here, we review the role of the above-mentioned intercellular communication in the HCC microecosystem and discuss the advantages of targeted intercellular communication in the clinical diagnosis and treatment of HCC. Finally, the current problems and prospects are discussed.
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Connexin Expression Is Altered in Liver Development of Yotari ( dab1 -/-) Mice. Int J Mol Sci 2021; 22:ijms221910712. [PMID: 34639052 PMCID: PMC8509723 DOI: 10.3390/ijms221910712] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 09/26/2021] [Accepted: 09/29/2021] [Indexed: 01/05/2023] Open
Abstract
Disabled-1 (Dab1) protein is an intracellular adaptor of reelin signaling required for prenatal neuronal migration, as well as postnatal neurotransmission, memory formation and synaptic plasticity. Yotari, an autosomal recessive mutant of the mouse Dab1 gene is recognizable by its premature death, unstable gait and tremor. Previous findings are mostly based on neuronal abnormalities caused by Dab1 deficiency, but the role of the reelin signaling pathway in nonneuronal tissues and organs has not been studied until recently. Hepatocytes, the most abundant cells in the liver, communicate via gap junctions (GJ) are composed of connexins. Cell communication disruption in yotari mice was examined by analyzing the expression of connexins (Cxs): Cx26, Cx32, Cx37, Cx40, Cx43 and Cx45 during liver development at 13.5 and 15.5 gestation days (E13.5 and E15.5). Analyses were performed using immunohistochemistry and fluorescent microscopy, followed by quantification of area percentage covered by positive signal. Data are expressed as a mean ± SD and analyzed by one-way ANOVA. All Cxs examined displayed a significant decrease in yotari compared to wild type (wt) individuals at E13.5. Looking at E15.5 we have similar results with exception of Cx37 showing negligible expression in wt. Channels formation triggered by pathological stimuli, as well as propensity to apoptosis, was studied by measuring the expression of Pannexin1 (Panx1) and Apoptosis-inducing factor (AIF) through developmental stages mentioned above. An increase in Panx1 expression of E15.5 yotari mice, as well as a strong jump of AIF in both phases suggesting that yotari mice are more prone to apoptosis. Our results emphasize the importance of gap junction intercellular communication (GJIC) during liver development and their possible involvement in liver pathology and diagnostics where they can serve as potential biomarkers and drug targets.
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Tirosh A, Tuncman G, Calay ES, Rathaus M, Ron I, Tirosh A, Yalcin A, Lee YG, Livne R, Ron S, Minsky N, Arruda AP, Hotamisligil GS. Intercellular Transmission of Hepatic ER Stress in Obesity Disrupts Systemic Metabolism. Cell Metab 2021; 33:319-333.e6. [PMID: 33340456 PMCID: PMC7858244 DOI: 10.1016/j.cmet.2020.11.009] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Revised: 07/30/2020] [Accepted: 11/12/2020] [Indexed: 12/22/2022]
Abstract
Endoplasmic reticulum stress (ERS) has a pathophysiological role in obesity-associated insulin resistance. Yet, the coordinated tissue response to ERS remains unclear. Increased connexin 43 (Cx43)-mediated intercellular communication has been implicated in tissue-adaptive and -maladaptive response to various chronic stresses. Here, we demonstrate that in hepatocytes, ERS results in increased Cx43 expression and cell-cell coupling. Co-culture of ER-stressed "donor" cells resulted in intercellular transmission of ERS and dysfunction to ERS-naive "recipient" cells ("bystander response"), which could be prevented by genetic or pharmacologic suppression of Cx43. Hepatocytes from obese mice were able to transmit ERS to hepatocytes from lean mice, and mice lacking liver Cx43 were protected from diet-induced ERS, insulin resistance, and hepatosteatosis. Taken together, our results indicate that in obesity, the increased Cx43-mediated cell-cell coupling allows intercellular propagation of ERS. This novel maladaptive response to over-nutrition exacerbates the tissue ERS burden, promoting hepatosteatosis and impairing whole-body glucose metabolism.
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Affiliation(s)
- Amir Tirosh
- Sabri Ülker Center for Metabolic Research, Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA; Division of Endocrinology, Diabetes and Hypertension, Brigham and Women's Hospital, Boston, MA 02115, USA; Division of Endocrinology, Diabetes and Metabolism, Sheba Medical Center, 52621 Tel-HaShomer, Israel; Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel; Harvard Medical School, Boston, MA 02115, USA.
| | - Gurol Tuncman
- Sabri Ülker Center for Metabolic Research, Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA
| | - Ediz S Calay
- Sabri Ülker Center for Metabolic Research, Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA
| | - Moran Rathaus
- Division of Endocrinology, Diabetes and Metabolism, Sheba Medical Center, 52621 Tel-HaShomer, Israel; Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Idit Ron
- Division of Endocrinology, Diabetes and Metabolism, Sheba Medical Center, 52621 Tel-HaShomer, Israel; Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Amit Tirosh
- Division of Endocrinology, Diabetes and Metabolism, Sheba Medical Center, 52621 Tel-HaShomer, Israel; Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Abdullah Yalcin
- Sabri Ülker Center for Metabolic Research, Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA; Adnan Menderes Üniversitesi Medical School, Department of Medical Biology, 09100 Aydin, Turkey
| | - Yankun G Lee
- Sabri Ülker Center for Metabolic Research, Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA
| | - Rinat Livne
- Division of Endocrinology, Diabetes and Metabolism, Sheba Medical Center, 52621 Tel-HaShomer, Israel; Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Sophie Ron
- Division of Endocrinology, Diabetes and Metabolism, Sheba Medical Center, 52621 Tel-HaShomer, Israel; Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Neri Minsky
- Division of Endocrinology, Diabetes and Metabolism, Sheba Medical Center, 52621 Tel-HaShomer, Israel; Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Ana Paula Arruda
- Sabri Ülker Center for Metabolic Research, Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA
| | - Gökhan S Hotamisligil
- Sabri Ülker Center for Metabolic Research, Molecular Metabolism, Harvard T.H. Chan School of Public Health, Boston, MA 02115, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA.
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Structure-Dependent Effects of Phthalates on Intercellular and Intracellular Communication in Liver Oval Cells. Int J Mol Sci 2020; 21:ijms21176069. [PMID: 32842520 PMCID: PMC7504421 DOI: 10.3390/ijms21176069] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Revised: 08/17/2020] [Accepted: 08/20/2020] [Indexed: 02/07/2023] Open
Abstract
Humans are exposed to phthalates released from plastics, cosmetics, or food on a daily basis. Phthalates have low acute liver toxicity, but their chronic exposures could induce molecular and cellular effects linked to adverse health outcomes, such as liver tumor promotion or chronic liver diseases. The alternation of gap junctional intercellular communication (GJIC) and MAPK-Erk1/2 pathways in liver progenitor or oval cells can disrupt liver tissue homeostatic mechanisms and affect the development and severity of these adverse outcomes. Our study with 20 different phthalates revealed their structurally dependent effects on liver GJIC and MAPK-Erk1/2 signaling in rat liver WB-F344 cell line with characteristics of liver oval cells. The phthalates with a medium-length side chain (3–6 C) were the most potent dysregulators of GJIC and activators of MAPK-Erk1/2. The effects occurred rapidly, suggesting the activation of non-genomic (non-transcriptional) mechanisms directly by the parental compounds. Short-chain phthalates (1–2 C) did not dysregulate GJIC even after longer exposures and did not activate MAPK-Erk1/2. Longer chain (≥7 C) phthalates, such as DEHP or DINP, moderately activated MAPK-Erk1/2, but inhibited GJIC only after prolonged exposures (>12 h), suggesting that GJIC dysregulation occurs via genomic mechanisms, or (bio)transformation. Overall, medium-chain phthalates rapidly affected the key tissue homeostatic mechanisms in the liver oval cell population via non-genomic pathways, which might contribute to the development of chronic liver toxicity and diseases.
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Wu S, Yao W, Chen C, Chen H, Huang F, Liu Y, Cai J, Yuan D, Hei Z. Connexin 32 deficiency protects the liver against ischemia/reperfusion injury. Eur J Pharmacol 2020; 876:173056. [PMID: 32147436 DOI: 10.1016/j.ejphar.2020.173056] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2019] [Revised: 02/28/2020] [Accepted: 02/28/2020] [Indexed: 12/11/2022]
Abstract
Hepatic ischemia/reperfusion (I/R) injury is a common complication in the clinical setting. Our previous study has shown that connexin 32 (Cx32) plays a major role in renal I/R injury; however, the role of Cx32 in hepatic I/R injury remains unknown. Liver tissue and serum samples from patients undergoing orthotopic liver transplantation (OLT) were used to evaluate the function of Cx32 in OLT post-reperfusion injury. Then, partial hepatic ischemia was established in global Cx32 knockout mice and wild-type mice followed by reperfusion. Hepatic injury markers were examined. Cx32 small interfering RNA and the p53 inhibitor, pifithrin-α, tenovin-1 were used to examine the relationship between Cx32 and the p53/puma pathways in the BRL-3A and murine primary hepatocytes hypoxia/reoxygenation (H/R) model. Corresponding to liver damage, Cx32 was significantly induced both during OLT in human patients and partial hepatic I/R in mice. Cx32 KO mice exhibited less liver injury than controls. Cx32 deficiency significantly suppressed the p53/puma pathways and hepatocyte apoptosis. Similar results were observed in the BRL-3A and murine primary hepatocytes H/R model. Propofol protected against OLT post-reperfusion injury and hepatocyte apoptosis by inhibiting Cx32. In conclusion Cx32 is a novel regulator of hepatic I/R injury through the modulation of hepatocyte apoptosis and damage, largely via the p53/puma signaling pathway.
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Affiliation(s)
- Shan Wu
- Department of Anesthesiology, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, 510630, China
| | - Weifeng Yao
- Department of Anesthesiology, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, 510630, China
| | - Chaojin Chen
- Department of Anesthesiology, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, 510630, China
| | - Huixin Chen
- Department of Anesthesiology, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, 510630, China
| | - Fei Huang
- Department of Anesthesiology, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, 510630, China
| | - Yiqian Liu
- Southern Medical University, Guangzhou, 510515, China
| | - Jun Cai
- Department of Anesthesiology, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, 510630, China.
| | - Dongdong Yuan
- Department of Anesthesiology, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, 510630, China.
| | - Ziqing Hei
- Department of Anesthesiology, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou, 510630, China.
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Yeo JH, Choi EJ, Lee J. Inhibition of gap junctional intercellular communication by an anti-migraine agent, flunarizine. PLoS One 2019; 14:e0222326. [PMID: 31513635 PMCID: PMC6742374 DOI: 10.1371/journal.pone.0222326] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Accepted: 08/27/2019] [Indexed: 02/08/2023] Open
Abstract
Gap junctions (GJs), which consist of proteins called connexins, are intercellular channels that allow the passage of ions, second messengers, and small molecules. GJs and connexins are considered as emerging therapeutic targets for various diseases. Previously, we screened numerous compounds using our recently developed iodide yellow fluorescent protein gap junctional intercellular communication (I-YFP GJIC) assay and found that flunarizine (FNZ), used for migraine prophylaxis and as an add-on therapy for epilepsy, inhibits GJIC in LN215 human glioma cells. In this study, we confirmed that FNZ inhibits GJIC using the I-YFP GJIC assay. We demonstrated that FNZ inhibits GJ activities via a mechanism that is independent of calcium channels and dopaminergic D2, histaminergic H1, or 5-HT receptors. In addition, we showed that FNZ significantly increases connexin 43 (Cx43) phosphorylation on the cell surface, but does not alter the total amount of Cx43. The beneficial effects of FNZ on migraines and epilepsy might be related to GJ inhibition.
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Affiliation(s)
- Joo Hye Yeo
- College of Pharmacy, Yonsei Institute of Pharmaceutical Sciences, Yonsei University, Songdogwahak-ro, Yeonsu-gu, Korea
| | - Eun Ju Choi
- College of Pharmacy, Yonsei Institute of Pharmaceutical Sciences, Yonsei University, Songdogwahak-ro, Yeonsu-gu, Korea
| | - Jinu Lee
- College of Pharmacy, Yonsei Institute of Pharmaceutical Sciences, Yonsei University, Songdogwahak-ro, Yeonsu-gu, Korea
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Hernández-Guerra M, Hadjihambi A, Jalan R. Gap junctions in liver disease: Implications for pathogenesis and therapy. J Hepatol 2019; 70:759-772. [PMID: 30599172 DOI: 10.1016/j.jhep.2018.12.023] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2018] [Revised: 12/03/2018] [Accepted: 12/12/2018] [Indexed: 02/07/2023]
Abstract
In the normal liver, cells interact closely through gap junctions. By providing a pathway for the trafficking of low molecular mass molecules, these channels contribute to tissue homeostasis and maintenance of hepatic function. Thus, dysfunction of gap junctions affects a wide variety of liver processes, such as differentiation, cell death, inflammation and fibrosis. In fact, dysfunctional gap junctions have been implicated, for more than a decade, in cholestatic disease, hepatic cancer and cirrhosis. Additionally, in recent years there is an increasing body of evidence that these channels are also involved in other relevant and prevalent liver pathological processes, such as non-alcoholic fatty liver disease, acute liver injury and portal hypertension. In parallel to these new clinical implications the available data include controversial observations. Thus, a comprehensive overview is required to better understand the functional complexity of these pores. This paper will review the most recent knowledge concerning gap junction dysfunction, with a special focus on the role of these channels in the pathogenesis of relevant clinical entities and on potential therapeutic targets that are amenable to modification by drugs.
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Affiliation(s)
| | | | - Rajiv Jalan
- UCL Institute for Liver and Digestive Health, Royal Free Medical School, London, UK
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Tarzemany R, Jiang G, Jiang JX, Larjava H, Häkkinen L. Connexin 43 Hemichannels Regulate the Expression of Wound Healing-Associated Genes in Human Gingival Fibroblasts. Sci Rep 2017; 7:14157. [PMID: 29074845 PMCID: PMC5658368 DOI: 10.1038/s41598-017-12672-1] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Accepted: 09/18/2017] [Indexed: 02/01/2023] Open
Abstract
Connexin 43 (Cx43) is the most ubiquitous connexin in various cells, and presents as hemichannels (HCs) and gap junctions (GJs) on the cell membrane. We have recently shown that Cx43 abundance was strongly reduced in fibroblasts of human gingival wounds, and blocking Cx43 function in cultured human gingival fibroblasts (GFBLs) strongly regulated the expression of wound healing-related genes. However, it is not known whether these responses involved Cx43 HCs or GJs. Here we show that Cx43 assembled into distinct GJ and HC plaques in GFBLs both in vivo and in vitro. Specific blockage of Cx43 HC function by TAT-Gap19, a Cx43 mimetic peptide, significantly upregulated the expression of several MMPs, TGF-β signaling molecules, Tenascin-C, and VEGF-A, while pro-fibrotic molecules, including several extracellular matrix proteins and myofibroblast and cell contractility-related molecules, were significantly downregulated. These changes were linked with TAT-Gap19-induced suppression of ATP signaling and activation of the ERK1/2 signaling pathway. Collectively, our data suggest that reduced Cx43 HC function could promote fast and scarless gingival wound healing. Thus, selective suppression of Cx43 HCs may provide a novel target to modulate wound healing.
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Affiliation(s)
- Rana Tarzemany
- Department of Oral Biological and Medical Sciences, Faculty of Dentistry, The University of British Columbia, Vancouver, BC, V6T 1Z3, Canada
| | - Guoqiao Jiang
- Department of Oral Biological and Medical Sciences, Faculty of Dentistry, The University of British Columbia, Vancouver, BC, V6T 1Z3, Canada
| | - Jean X Jiang
- Department of Biochemistry, University of Texas Health Science Center, San Antonio, Texas, 78229-3900, USA
| | - Hannu Larjava
- Department of Oral Biological and Medical Sciences, Faculty of Dentistry, The University of British Columbia, Vancouver, BC, V6T 1Z3, Canada
| | - Lari Häkkinen
- Department of Oral Biological and Medical Sciences, Faculty of Dentistry, The University of British Columbia, Vancouver, BC, V6T 1Z3, Canada.
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12
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Willebrords J, Cogliati B, Pereira IVA, da Silva TC, Crespo Yanguas S, Maes M, Govoni VM, Lima A, Felisbino DA, Decrock E, Nogueira MS, de Castro IA, Leclercq I, Leybaert L, Rodrigues RM, Vinken M. Inhibition of connexin hemichannels alleviates non-alcoholic steatohepatitis in mice. Sci Rep 2017; 7:8268. [PMID: 28811572 PMCID: PMC5557827 DOI: 10.1038/s41598-017-08583-w] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Accepted: 07/27/2017] [Indexed: 12/26/2022] Open
Abstract
While gap junctions mediate intercellular communication and support liver homeostasis, connexin hemichannels are preferentially opened by pathological stimuli, including inflammation and oxidative stress. The latter are essential features of non-alcoholic steatohepatitis. In this study, it was investigated whether connexin32 and connexin43 hemichannels play a role in non-alcoholic steatohepatitis. Mice were fed a choline-deficient high-fat diet or normal diet for 8 weeks. Thereafter, TAT-Gap24 or TAT-Gap19, specific inhibitors of hemichannels composed of connexin32 and connexin43, respectively, were administered for 2 weeks. Subsequently, histopathological examination was carried out and various indicators of inflammation, liver damage and oxidative stress were tested. In addition, whole transcriptome microarray analysis of liver tissue was performed. Channel specificity of TAT-Gap24 and TAT-Gap19 was examined in vitro by fluorescence recovery after photobleaching analysis and measurement of extracellular release of adenosine triphosphate. TAT-Gap24 and TAT-Gap19 were shown to be hemichannel-specific in cultured primary hepatocytes. Diet-fed animals treated with TAT-Gap24 or TAT-Gap19 displayed decreased amounts of liver lipids and inflammatory markers, and augmented levels of superoxide dismutase, which was supported by the microarray results. These findings show the involvement of connexin32 and connexin43 hemichannels in non-alcoholic steatohepatitis and, simultaneously, suggest a role as potential drug targets in non-alcoholic steatohepatitis.
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Affiliation(s)
- Joost Willebrords
- Department of In Vitro Toxicology and Dermato-Cosmetology, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090, Brussels, Belgium
| | - Bruno Cogliati
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of São Paulo, Av. Prof. Dr. Orlando Marques de Paiva 87, 05508-270, São Paulo, Brazil
| | - Isabel Veloso Alves Pereira
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of São Paulo, Av. Prof. Dr. Orlando Marques de Paiva 87, 05508-270, São Paulo, Brazil
| | - Tereza Cristina da Silva
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of São Paulo, Av. Prof. Dr. Orlando Marques de Paiva 87, 05508-270, São Paulo, Brazil
| | - Sara Crespo Yanguas
- Department of In Vitro Toxicology and Dermato-Cosmetology, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090, Brussels, Belgium
| | - Michaël Maes
- Department of In Vitro Toxicology and Dermato-Cosmetology, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090, Brussels, Belgium
| | - Veronica Mollica Govoni
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of São Paulo, Av. Prof. Dr. Orlando Marques de Paiva 87, 05508-270, São Paulo, Brazil
| | - Andressa Lima
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of São Paulo, Av. Prof. Dr. Orlando Marques de Paiva 87, 05508-270, São Paulo, Brazil
| | - Daniele Aparecida Felisbino
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of São Paulo, Av. Prof. Dr. Orlando Marques de Paiva 87, 05508-270, São Paulo, Brazil
| | - Elke Decrock
- Department of Basic Medical Sciences, Physiology Group, Ghent University, De Pintelaan 185, 9000, Ghent, Belgium
| | - Marina Sayuri Nogueira
- Department of Food and Experimental Nutrition, Faculty of Pharmaceutical Sciences, University of São Paulo, Av. Prof. Lineu Prestes 580, 05508-270, São Paulo, Brazil
| | - Inar Alves de Castro
- Department of Food and Experimental Nutrition, Faculty of Pharmaceutical Sciences, University of São Paulo, Av. Prof. Lineu Prestes 580, 05508-270, São Paulo, Brazil
| | - Isabelle Leclercq
- Laboratory of hepatogastroenterology, Institut de Recherche Expérimentale et clinique, Université catholique de Louvain, Avenue Mounier 53, 1200, Brussels, Belgium
| | - Luc Leybaert
- Department of Basic Medical Sciences, Physiology Group, Ghent University, De Pintelaan 185, 9000, Ghent, Belgium
| | - Robim Marcelino Rodrigues
- Department of In Vitro Toxicology and Dermato-Cosmetology, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090, Brussels, Belgium
| | - Mathieu Vinken
- Department of In Vitro Toxicology and Dermato-Cosmetology, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090, Brussels, Belgium.
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13
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Maes M, Crespo Yanguas S, Willebrords J, Weemhoff JL, da Silva TC, Decrock E, Lebofsky M, Pereira IVA, Leybaert L, Farhood A, Jaeschke H, Cogliati B, Vinken M. Connexin hemichannel inhibition reduces acetaminophen-induced liver injury in mice. Toxicol Lett 2017; 278:30-37. [PMID: 28687253 PMCID: PMC5800489 DOI: 10.1016/j.toxlet.2017.07.007] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Revised: 06/27/2017] [Accepted: 07/01/2017] [Indexed: 02/07/2023]
Abstract
Historically, connexin hemichannels have been considered as structural precursors of gap junctions. However, accumulating evidence points to independent roles for connexin hemichannels in cellular signaling by connecting the intracellular compartment with the extracellular environment. Unlike gap junctions, connexin hemichannels seem to be mainly activated in pathological processes. The present study was set up to test the potential involvement of hemichannels composed of connexin32 and connexin43 in acute hepatotoxicity induced by acetaminophen. Prior to this, in vitro testing was performed to confirm the specificity and efficacy of TAT-Gap24 and TAT-Gap19 in blocking connexin32 and connexin43 hemichannels, respectively. Subsequently, mice were overdosed with acetaminophen followed by treatment with TAT-Gap24 or TAT-Gap19 or a combination of both after 1.5h. Sampling was performed 3, 6, 24 and 48h following acetaminophen administration. Evaluation of the effects of connexin hemichannel inhibition was based on a series of clinically relevant read-outs, measurement of inflammatory cytokines and oxidative stress. Subsequent treatment of acetaminophen-overdosed mice with TAT-Gap19 only marginally affected liver injury. In contrast, a significant reduction in serum alanine aminotransferase activity was found upon administration of TAT-Gap24 to intoxicated animals. Furthermore, co-treatment of acetaminophen-overdosed mice with both peptides revealed an additive effect as even lower serum alanine aminotransferase activity was observed. Blocking of connexin32 or connexin43 hemichannels individually was found to decrease serum quantities of pro-inflammatory cytokines, while no effects were observed on the occurrence of hepatic oxidative stress. This study shows for the first time a role for connexin hemichannels in acetaminophen-induced acute liver failure.
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Affiliation(s)
- Michaël Maes
- Department of In Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel, Brussels, Belgium.
| | - Sara Crespo Yanguas
- Department of In Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel, Brussels, Belgium.
| | - Joost Willebrords
- Department of In Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel, Brussels, Belgium.
| | - James L Weemhoff
- Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, United States.
| | - Tereza Cristina da Silva
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of São Paulo, São Paulo, Brazil.
| | - Elke Decrock
- Department of Basic Medical Sciences, Physiology Group, Ghent University, Ghent, Belgium.
| | - Margitta Lebofsky
- Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, United States.
| | - Isabel Veloso Alves Pereira
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of São Paulo, São Paulo, Brazil.
| | - Luc Leybaert
- Department of Basic Medical Sciences, Physiology Group, Ghent University, Ghent, Belgium.
| | - Anwar Farhood
- Department of Pathology, St. David's North Austin Medical Center, Austin, United States.
| | - Hartmut Jaeschke
- Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, United States.
| | - Bruno Cogliati
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of São Paulo, São Paulo, Brazil.
| | - Mathieu Vinken
- Department of In Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel, Brussels, Belgium.
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14
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Ramachandran A, Jaeschke H. Mechanisms of acetaminophen hepatotoxicity and their translation to the human pathophysiology. J Clin Transl Res 2017; 3:157-169. [PMID: 28670625 PMCID: PMC5489132 DOI: 10.18053/jctres.03.2017s1.002] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Acetaminophen (APAP) overdose is the most common cause of acute liver failure in the United States and mechanisms of liver injury induced by APAP overdose have been the focus of extensive investigation. Studies in the mouse model, which closely reproduces the human condition, have shown that hepatotoxicity is initiated by formation of a reactive metabolite N-acetyl-p-benzoquinone imine (NAPQI), which depletes cellular glutathione and forms protein adducts on mitochondrial proteins. This leads to mitochondrial oxidative and nitrosative stress, accompanied by activation of c-jun N-terminal kinase (JNK) and its translocation to the mitochondria. This then amplifies the mitochondrial oxidant stress, resulting in translocation of Bax and dynamin related protein 1 (Drp1) to the mitochondria, which induces mitochondrial fission, and ultimately induction of the mitochondrial membrane permeability transition (MPT). The induction of MPT triggers release of intermembrane proteins such as apoptosis inducing factor (AIF) and endonuclease G into the cytosol and their translocation to the nucleus, causing nuclear DNA fragmentation and activation of regulated necrosis. Though these cascades of events were primarily identified in the mouse model, studies on human hepatocytes and analysis of circulating biomarkers from patients after APAP overdose, indicate that a number of mechanistic events are identical in mice and humans. Circulating biomarkers also seem to be useful in predicting the course of liver injury after APAP overdose in humans and hold promise for significant clinical use in the near future. Relevance for patients: This review focuses on the mechanisms behind APAP-induced hepatotoxicity and the relevance of these to the human pathophysiology. Current investigations on various biomarkers which may be useful in clinical management of APAP overdose patients are also discussed.
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Affiliation(s)
- Anup Ramachandran
- Department of Pharmacology, Toxicology & Therapeutics, University of Kansas Medical Center, Kansas City, KS 66160, USA
| | - Hartmut Jaeschke
- Department of Pharmacology, Toxicology & Therapeutics, University of Kansas Medical Center, Kansas City, KS 66160, USA
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15
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Abstract
Being critical mediators of liver homeostasis, connexins and their channels are frequently involved in liver toxicity. In the current paper, specific attention is paid to actions of hepatotoxic drugs on these communicative structures. In a first part, an overview is provided on the structural, regulatory and functional properties of connexin-based channels in the liver. In the second part, documented effects of acetaminophen, hypolipidemic drugs, phenobarbital and methapyriline on connexin signaling are discussed. Furthermore, the relevance of this subject for the fields of clinical and in vitro toxicology is demonstrated. Relevance for patients: The role of connexin signaling in drug-induced hepatotoxicity may be of high clinical relevance, as it offers perspectives for the therapeutic treatment of such insults by interfering with connexin channel opening.
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Affiliation(s)
- Michaël Maes
- Department of In Vitro Toxicology and Dermato-Cosmetology, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, Brussels, Belgium
| | - Mathieu Vinken
- Department of In Vitro Toxicology and Dermato-Cosmetology, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, Brussels, Belgium
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16
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Tiburcio TC, Willebrords J, da Silva TC, Alves Pereira IV, Nogueira MS, Crespo Yanguas S, Maes M, dos Anjos Silva E, Zaidan Dagli ML, Alves de Castro I, Pinto Oliveira C, Vinken M, Cogliati B. Connexin32 deficiency is associated with liver injury, inflammation and oxidative stress in experimental non-alcoholic steatohepatitis. Clin Exp Pharmacol Physiol 2017; 44:197-206. [PMID: 27859493 PMCID: PMC5689377 DOI: 10.1111/1440-1681.12701] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2016] [Revised: 11/11/2016] [Accepted: 11/15/2016] [Indexed: 01/09/2023]
Abstract
Non-alcoholic steatohepatitis is a highly prevalent liver pathology featured by hepatocellular fat deposition and inflammation. Connexin32, which is the major building block of hepatocellular gap junctions, has a protective role in hepatocarcinogenesis and is downregulated in chronic liver diseases. However, the role of connexin32 in non-alcoholic steatohepatitis remains unclear. Connexin32-/- mice and their wild-type littermates were fed a choline-deficient high-fat diet. The manifestation of non-alcoholic steatohepatitis was evaluated based on a battery of clinically relevant read-outs, including histopathological examination, diverse indicators of inflammation and liver damage, in-depth lipid analysis, assessment of oxidative stress, insulin and glucose tolerance, liver regeneration and lipid-related biomarkers. Overall, more pronounced liver damage, inflammation and oxidative stress were observed in connexin32-/- mice compared to wild-type animals. No differences were found in insulin and glucose tolerance measurements and liver regeneration. However, two lipid-related genes, srebf1 and fabp3, were upregulated in Cx32-/- mice in comparison with wild-type animals. These findings suggest that connexin32-based signalling is not directly involved in steatosis as such, but rather in the sequelae of this process, which underlie progression of non-alcoholic steatohepatitis.
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Affiliation(s)
- Taynã Cristina Tiburcio
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of São Paulo, Av. Prof. Dr. Orlando Marques de Paiva 87, 05508-270 São Paulo, Brazil
| | - Joost Willebrords
- Department of In Vitro Toxicology and Dermato-Cosmetology, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels, Belgium
| | - Tereza Cristina da Silva
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of São Paulo, Av. Prof. Dr. Orlando Marques de Paiva 87, 05508-270 São Paulo, Brazil
| | - Isabel Veloso Alves Pereira
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of São Paulo, Av. Prof. Dr. Orlando Marques de Paiva 87, 05508-270 São Paulo, Brazil
| | - Marina Sayuri Nogueira
- Department of Food and Experimental Nutrition, Faculty of Pharmaceutical Sciences, University of São Paulo, Av. Prof. Lineu Prestes 580, São Paulo, Brazil
| | - Sara Crespo Yanguas
- Department of In Vitro Toxicology and Dermato-Cosmetology, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels, Belgium
| | - Michaël Maes
- Department of In Vitro Toxicology and Dermato-Cosmetology, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels, Belgium
| | - Elisangela dos Anjos Silva
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of São Paulo, Av. Prof. Dr. Orlando Marques de Paiva 87, 05508-270 São Paulo, Brazil
| | - Maria Lucia Zaidan Dagli
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of São Paulo, Av. Prof. Dr. Orlando Marques de Paiva 87, 05508-270 São Paulo, Brazil
| | - Inar Alves de Castro
- Department of Food and Experimental Nutrition, Faculty of Pharmaceutical Sciences, University of São Paulo, Av. Prof. Lineu Prestes 580, São Paulo, Brazil
| | - Cláudia Pinto Oliveira
- Department of Gastroenterology, Clinical Division, Hepatology Branch, University of São Paulo School of Medicine, Av. Dr. Arnaldo 455, São Paulo, Brazil
| | - Mathieu Vinken
- Department of In Vitro Toxicology and Dermato-Cosmetology, Faculty of Medicine and Pharmacy, Vrije Universiteit Brussel, Laarbeeklaan 103, 1090 Brussels, Belgium
| | - Bruno Cogliati
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of São Paulo, Av. Prof. Dr. Orlando Marques de Paiva 87, 05508-270 São Paulo, Brazil
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17
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Qin J, Chang M, Wang S, Liu Z, Zhu W, Wang Y, Yan F, Li J, Zhang B, Dou G, Liu J, Pei X, Wang Y. Connexin 32-mediated cell-cell communication is essential for hepatic differentiation from human embryonic stem cells. Sci Rep 2016; 6:37388. [PMID: 27874032 PMCID: PMC5118817 DOI: 10.1038/srep37388] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2016] [Accepted: 10/28/2016] [Indexed: 12/13/2022] Open
Abstract
Gap junction-mediated cell-cell interactions are highly conserved and play essential roles in cell survival, proliferation, differentiation and patterning. We report that Connexin 32 (Cx32)-mediated gap junctional intercellular communication (GJIC) is necessary for human embryonic stem cell-derived hepatocytes (hESC-Heps) during step-wise hepatic lineage restriction and maturation. Vitamin K2, previously shown to promote Cx32 expression in mature hepatocytes, up-regulated Cx32 expression and GJIC activation during hepatic differentiation and maturation, resulting in significant increases of hepatic markers expression and hepatocyte functions. In contrast, negative Cx32 regulator 2-aminoethoxydiphenyl borate blocked hESC-to-hepatocyte maturation and muted hepatocyte functions through disruption of GJIC activities. Dynamic gap junction organization and internalization are phosphorylation-dependent and the p38 mitogen-activated protein kinases pathway (MAPK) can negatively regulate Cxs through phosphorylation-dependent degradation of Cxs. We found that p38 MAPK inhibitor SB203580 improved maturation of hESC-Heps correlating with up-regulation of Cx32; by contrast, the p38 MAPK activator, anisomycin, blocked hESC-Heps maturation correlating with down-regulation of Cx32. These results suggested that Cx32 is essential for cell-cell interactions that facilitate driving hESCs through hepatic-lineage maturation. Regulators of both Cx32 and other members of its pathways maybe used as a promising approach on regulating hepatic lineage restriction of pluripotent stem cells and optimizing their functional maturation.
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Affiliation(s)
- Jinhua Qin
- Stem Cell and Regenerative Medicine Lab, Beijing Institute of Transfusion Medicine, Beijing 100850, China
- Tissue Engineering Lab, Beijing Institute of Transfusion Medicine, Beijing 100850, China
- South China Research Center for Stem Cell and Regenerative Medicine, South China Institute of Biomedicine, Guangzhou 510005, China
| | - Mingyang Chang
- Tissue Engineering Lab, Beijing Institute of Transfusion Medicine, Beijing 100850, China
| | - Shuyong Wang
- Stem Cell and Regenerative Medicine Lab, Beijing Institute of Transfusion Medicine, Beijing 100850, China
- Tissue Engineering Lab, Beijing Institute of Transfusion Medicine, Beijing 100850, China
- South China Research Center for Stem Cell and Regenerative Medicine, South China Institute of Biomedicine, Guangzhou 510005, China
| | - Zhenbo Liu
- CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100101, China
| | - Wei Zhu
- CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100101, China
| | - Yi Wang
- Tissue Engineering Lab, Beijing Institute of Transfusion Medicine, Beijing 100850, China
| | - Fang Yan
- Tissue Engineering Lab, Beijing Institute of Transfusion Medicine, Beijing 100850, China
| | - Jian Li
- Laboratory of Hematological Pharmacology, Beijing Institute of Transfusion Medicine, Beijing 100850, China
| | - Bowen Zhang
- Stem Cell and Regenerative Medicine Lab, Beijing Institute of Transfusion Medicine, Beijing 100850, China
- South China Research Center for Stem Cell and Regenerative Medicine, South China Institute of Biomedicine, Guangzhou 510005, China
| | - Guifang Dou
- Laboratory of Hematological Pharmacology, Beijing Institute of Transfusion Medicine, Beijing 100850, China
| | - Jiang Liu
- CAS Key Laboratory of Genome Sciences and Information, Beijing Institute of Genomics, Chinese Academy of Sciences, Beijing 100101, China
| | - Xuetao Pei
- Stem Cell and Regenerative Medicine Lab, Beijing Institute of Transfusion Medicine, Beijing 100850, China
- South China Research Center for Stem Cell and Regenerative Medicine, South China Institute of Biomedicine, Guangzhou 510005, China
| | - Yunfang Wang
- Tissue Engineering Lab, Beijing Institute of Transfusion Medicine, Beijing 100850, China
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18
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Cogliati B, Crespo Yanguas S, da Silva TC, Aloia TP, Nogueira MS, Real-Lima MA, Chaible LM, Sanches DS, Willebrords J, Maes M, Pereira IV, de Castro IA, Vinken M, Dagli ML. Connexin32 deficiency exacerbates carbon tetrachloride-induced hepatocellular injury and liver fibrosis in mice. Toxicol Mech Methods 2016; 26:362-370. [PMID: 27268753 PMCID: PMC5417356 DOI: 10.1080/15376516.2016.1190991] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
OBJECTIVE Liver fibrosis results from the perpetuation of the normal wound healing response to several types of injury. Despite the wealth of knowledge regarding the involvement of intracellular and extracellular signaling pathways in liver fibrogenesis, information about the role of intercellular communication mediated by gap junctions is scarce. METHODS In this study, liver fibrosis was chemically induced by carbon tetrachloride in mice lacking connexin32, the major liver gap junction constituent. The manifestation of liver fibrosis was evaluated based on a series of read-outs, including collagen morphometric and mRNA analysis, oxidative stress, apoptotic, proliferative and inflammatory markers. RESULTS More pronounced liver damage and enhanced collagen deposition were observed in connexin32 knockout mice compared to wild-type animals in experimentally triggered induced liver fibrosis. No differences between both groups were noticed in apoptotic signaling nor in inflammation markers. However, connexin32 deficient mice displayed decreased catalase activity and increased malondialdehyde levels. CONCLUSION These findings could suggest that connexin32-based signaling mediates tissue resistance against liver damage by the modulation of the antioxidant capacity. In turn, this could point to a role for connexin32 signaling as a therapeutic target in the treatment of liver fibrosis.
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Affiliation(s)
- Bruno Cogliati
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of Sao Paulo, Sao Paulo, Brazil
| | - Sara Crespo Yanguas
- Department of In Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel, Brussels, Belgium
| | - Tereza C. da Silva
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of Sao Paulo, Sao Paulo, Brazil
| | - Thiago P.A. Aloia
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of Sao Paulo, Sao Paulo, Brazil
| | - Marina S. Nogueira
- Department of Food and Experimental Nutrition, Faculty of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | - Mirela A. Real-Lima
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of Sao Paulo, Sao Paulo, Brazil
| | - Lucas M. Chaible
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of Sao Paulo, Sao Paulo, Brazil
| | - Daniel S. Sanches
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of Sao Paulo, Sao Paulo, Brazil
| | - Joost Willebrords
- Department of In Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel, Brussels, Belgium
| | - Michaël Maes
- Department of In Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel, Brussels, Belgium
| | - Isabel V.A. Pereira
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of Sao Paulo, Sao Paulo, Brazil
| | - Inar A. de Castro
- Department of Food and Experimental Nutrition, Faculty of Pharmaceutical Sciences, University of São Paulo, São Paulo, Brazil
| | - Mathieu Vinken
- Department of In Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel, Brussels, Belgium
| | - Maria L.Z. Dagli
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of Sao Paulo, Sao Paulo, Brazil
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19
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Maes M, McGill MR, da Silva TC, Abels C, Lebofsky M, Maria Monteiro de Araújo C, Tiburcio T, Veloso Alves Pereira I, Willebrords J, Crespo Yanguas S, Farhood A, Beschin A, Van Ginderachter JA, Zaidan Dagli ML, Jaeschke H, Cogliati B, Vinken M. Involvement of connexin43 in acetaminophen-induced liver injury. Biochim Biophys Acta Mol Basis Dis 2016; 1862:1111-21. [PMID: 26912412 DOI: 10.1016/j.bbadis.2016.02.007] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2015] [Revised: 02/06/2016] [Accepted: 02/17/2016] [Indexed: 01/17/2023]
Abstract
BACKGROUND AND AIMS Being goalkeepers of liver homeostasis, gap junctions are also involved in hepatotoxicity. However, their role in this process is ambiguous, as gap junctions can act as both targets and effectors of liver toxicity. This particularly holds true for drug-induced liver insults. In the present study, the involvement of connexin26, connexin32 and connexin43, the building blocks of liver gap junctions, was investigated in acetaminophen-induced hepatotoxicity. METHODS C57BL/6 mice were overdosed with 300mg/kg body weight acetaminophen followed by analysis of the expression and localization of connexins as well as monitoring of hepatic gap junction functionality. Furthermore, acetaminophen-induced liver injury was compared between mice genetically deficient in connexin43 and wild type littermates. Evaluation of the toxicological response was based on a set of clinically relevant parameters, including protein adduct formation, measurement of alanine aminotransferase activity, cytokines and glutathione. RESULTS It was found that gap junction communication deteriorates upon acetaminophen intoxication in wild type mice, which is associated with a switch in mRNA and protein production from connexin32 and connexin26 to connexin43. The upregulation of connexin43 expression is due, at least in part, to de novo production by hepatocytes. Connexin43-deficient animals tended to show increased liver cell death, inflammation and oxidative stress in comparison with wild type counterparts. CONCLUSION These results suggest that hepatic connexin43-based signaling may protect against acetaminophen-induced liver toxicity.
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Affiliation(s)
- Michaël Maes
- Department of In Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel, Brussels, Belgium
| | - Mitchell R McGill
- Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, United States
| | - Tereza Cristina da Silva
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of São Paulo, São Paulo, Brazil
| | - Chloé Abels
- Myeloid Cell Immunology Lab, VIB Inflammation Research Center, Ghent, Belgium; Lab of Cellular and Molecular Immunology, Vrije Universiteit Brussel, Brussels, Belgium
| | - Margitta Lebofsky
- Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, United States
| | | | - Taynã Tiburcio
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of São Paulo, São Paulo, Brazil
| | - Isabel Veloso Alves Pereira
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of São Paulo, São Paulo, Brazil
| | - Joost Willebrords
- Department of In Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel, Brussels, Belgium
| | - Sara Crespo Yanguas
- Department of In Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel, Brussels, Belgium
| | - Anwar Farhood
- Department of Pathology, St. David's North Austin Medical Center, Austin, United States
| | - Alain Beschin
- Myeloid Cell Immunology Lab, VIB Inflammation Research Center, Ghent, Belgium; Lab of Cellular and Molecular Immunology, Vrije Universiteit Brussel, Brussels, Belgium
| | - Jo A Van Ginderachter
- Myeloid Cell Immunology Lab, VIB Inflammation Research Center, Ghent, Belgium; Lab of Cellular and Molecular Immunology, Vrije Universiteit Brussel, Brussels, Belgium
| | - Maria Lucia Zaidan Dagli
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of São Paulo, São Paulo, Brazil
| | - Hartmut Jaeschke
- Department of Pharmacology, Toxicology and Therapeutics, University of Kansas Medical Center, Kansas City, United States
| | - Bruno Cogliati
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of São Paulo, São Paulo, Brazil
| | - Mathieu Vinken
- Department of In Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel, Brussels, Belgium.
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20
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Maes M, Yanguas SC, Willebrords J, Vinken M. Models and methods for in vitro testing of hepatic gap junctional communication. Toxicol In Vitro 2015; 30:569-577. [PMID: 26420514 PMCID: PMC4685743 DOI: 10.1016/j.tiv.2015.09.024] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Revised: 08/11/2015] [Accepted: 09/24/2015] [Indexed: 12/17/2022]
Abstract
Inherent to their pivotal roles in controlling all aspects of the liver cell life cycle, hepatocellular gap junctions are frequently disrupted upon impairment of the homeostatic balance, as occurs during liver toxicity. Hepatic gap junctions, which are mainly built up by connexin32, are specifically targeted by tumor promoters and epigenetic carcinogens. This renders inhibition of gap junction functionality a suitable indicator for the in vitro detection of nongenotoxic hepatocarcinogenicity. The establishment of a reliable liver gap junction inhibition assay for routine in vitro testing purposes requires a cellular system in which gap junctions are expressed at an in vivo-like level as well as an appropriate technique to probe gap junction activity. Both these models and methods are discussed in the current paper, thereby focusing on connexin32-based gap junctions.
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Affiliation(s)
- Michaël Maes
- Department of In Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel, Laarbeeklaan 103, B-1090 Brussels, Belgium
| | - Sara Crespo Yanguas
- Department of In Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel, Laarbeeklaan 103, B-1090 Brussels, Belgium
| | - Joost Willebrords
- Department of In Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel, Laarbeeklaan 103, B-1090 Brussels, Belgium
| | - Mathieu Vinken
- Department of In Vitro Toxicology and Dermato-Cosmetology, Vrije Universiteit Brussel, Laarbeeklaan 103, B-1090 Brussels, Belgium
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21
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Sala G, Badalamenti S, Ponticelli C. The Renal Connexome and Possible Roles of Connexins in Kidney Diseases. Am J Kidney Dis 2015; 67:677-87. [PMID: 26613807 DOI: 10.1053/j.ajkd.2015.09.030] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2015] [Accepted: 09/30/2015] [Indexed: 12/21/2022]
Abstract
Connexins are membrane-spanning proteins that allow for the formation of cell-to-cell channels and cell-to-extracellular space hemichannels. Many connexin subtypes are expressed in kidney cells. Some mutations in connexin genes have been linked to various human pathologies, including cardiovascular, neurodegenerative, lung, and skin diseases, but the exact role of connexins in kidney disease remains unclear. Some hypotheses about a connection between genetic mutations, endoplasmic reticulum (ER) stress, and the unfolded protein response (UPR) in kidney pathology have been explored. The potential relationship of kidney disease to abnormal production of connexin proteins, mutations in their genes together with ER stress, or the UPR is still a matter of debate. In this scenario, it is tantalizing to speculate about a possible role of connexins in the setting of kidney pathologies that are thought to be caused by a deregulated podocyte protein expression, the so-called podocytopathies. In this article, we give examples of the roles of connexins in kidney (patho)physiology and propose avenues for further research concerning connexins, ER stress, and UPR in podocytopathies that may ultimately help refine drug treatment.
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Affiliation(s)
- Gabriele Sala
- Nephrology and Dialysis Unit, Humanitas Clinical Research Center, Rozzano (Milano), Italy.
| | - Salvatore Badalamenti
- Nephrology and Dialysis Unit, Humanitas Clinical Research Center, Rozzano (Milano), Italy
| | - Claudio Ponticelli
- Nephrology and Dialysis Unit, Humanitas Clinical Research Center, Rozzano (Milano), Italy
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22
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Santos T, Cancian G, Neodini DNR, Mano DRS, Capucho C, Predes FS, Barbieri R, Oliveira CA, Pigoso AA, Dolder H, Severi-Aguiar GDC. Toxicological evaluation of ametryn effects in Wistar rats. ACTA ACUST UNITED AC 2015; 67:525-32. [PMID: 26310382 DOI: 10.1016/j.etp.2015.08.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Revised: 06/25/2015] [Accepted: 08/04/2015] [Indexed: 10/25/2022]
Abstract
São Paulo state, Brazil, is one of the main areas of sugar cane planting in the world. Extensive use of ametryn, a triazine herbicide, in sugar cane agriculture and the properties of this herbicide suggest it could be present in the environment as a potential contaminant of soil, surface water, groundwater, and river sediment. In order to clarify the mechanism through which ametryn could be toxic, an in vivo study with Wistar rats was conducted using hematological, biochemical, molecular, morphological and genotoxic approaches. For this purpose, two sub-lethal ametryn concentrations (15 mg and 30 mg/kg/day) were administered to 42 rats divided into three groups (n=12) by gavage during 56 days, whereupon blood, liver and bone marrow were collected. The results showed ametryn genotoxic activity by in vivo micronuclei testing. This event probably occurred as consequence of oxidative stress induction demonstrated by GSTM1 transcript levels increase (indicating complexation between ametryn and/or metabolites with GSH) and by SOD activity decrease. Also, Mn-SOD transcripts were increased, probably avoiding mtDNA damage caused by EROS. These mechanisms displayed hepatic stellate cell (HSCs) activation because two major biomarkers were regulated, connexin and cadherin. N-cad transcripts were increased on both exposed groups while E-cad decreased in the T1 group, indicating epithelial-to-mesenchymal transition. In addition, Cx43 transcripts were decreased suggesting an increase in collagen content. Volumetric proportion of sinusoids was significantly decreased in T1 group and no significant alteration in hepatocyte volume was observed, indicating an increase in the space of Disse, due to fibrosis. Hepatocyte nuclei showed significant decrease in diameter and volume. Few hematological alterations were found. We emphasize the importance of other approaches, such as cell death and proliferation assays, so that ametryn toxicity can better be understood.
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Affiliation(s)
- Tamires Santos
- Programa de Pós-Graduação em Ciências Biomédicas, Centro Universitário Hermínio Ometto, UNIARARAS, Avenida Dr. Maximiliano Barutto, n° 500, Jd. Universitário, Araras, São Paulo, Brazil, CEP 13607-339
| | - Graziela Cancian
- NUCISA - Núcleo de Ciências da Saúde, Centro Universitário Hermínio Ometto, UNIARARAS, Avenida Dr. Maximiliano Barutto, n° 500, Jd. Universitário, Araras, São Paulo, Brazil, CEP 13607-339
| | - Daniella N R Neodini
- NUCISA - Núcleo de Ciências da Saúde, Centro Universitário Hermínio Ometto, UNIARARAS, Avenida Dr. Maximiliano Barutto, n° 500, Jd. Universitário, Araras, São Paulo, Brazil, CEP 13607-339
| | - Deiviston R S Mano
- NUCISA - Núcleo de Ciências da Saúde, Centro Universitário Hermínio Ometto, UNIARARAS, Avenida Dr. Maximiliano Barutto, n° 500, Jd. Universitário, Araras, São Paulo, Brazil, CEP 13607-339
| | - Cristina Capucho
- NUCISA - Núcleo de Ciências da Saúde, Centro Universitário Hermínio Ometto, UNIARARAS, Avenida Dr. Maximiliano Barutto, n° 500, Jd. Universitário, Araras, São Paulo, Brazil, CEP 13607-339
| | - Fabrícia S Predes
- Universidade Estadual do Paraná- UNESPAR/Campus Paranaguá, Rua Comendador Correa Junior, 117, Centro, Paranaguá, Paraná, Brazil, CEP 83203-560
| | - Renata Barbieri
- NUCISA - Núcleo de Ciências da Saúde, Centro Universitário Hermínio Ometto, UNIARARAS, Avenida Dr. Maximiliano Barutto, n° 500, Jd. Universitário, Araras, São Paulo, Brazil, CEP 13607-339
| | - Camila A Oliveira
- Programa de Pós-Graduação em Ciências Biomédicas, Centro Universitário Hermínio Ometto, UNIARARAS, Avenida Dr. Maximiliano Barutto, n° 500, Jd. Universitário, Araras, São Paulo, Brazil, CEP 13607-339
| | - Acácio A Pigoso
- NUCISA - Núcleo de Ciências da Saúde, Centro Universitário Hermínio Ometto, UNIARARAS, Avenida Dr. Maximiliano Barutto, n° 500, Jd. Universitário, Araras, São Paulo, Brazil, CEP 13607-339
| | - Heidi Dolder
- Laboratório de Biologia da Reprodução, Departamento de Biologia Estrutural e Funcional, Universidade Estadual de Campinas - UNICAMP,CP. 6109, Campinas, São Paulo, Brasil, CEP 13083-863
| | - Grasiela D C Severi-Aguiar
- Programa de Pós-Graduação em Ciências Biomédicas, Centro Universitário Hermínio Ometto, UNIARARAS, Avenida Dr. Maximiliano Barutto, n° 500, Jd. Universitário, Araras, São Paulo, Brazil, CEP 13607-339; Laboratório de Biologia da Reprodução, Departamento de Biologia Estrutural e Funcional, Universidade Estadual de Campinas - UNICAMP,CP. 6109, Campinas, São Paulo, Brasil, CEP 13083-863.
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23
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Wang R, Huang F, Chen Z, Li S. Downregulation of connexin 32 attenuates hypoxia/reoxygenation injury in liver cells. J Biochem Mol Toxicol 2015; 29:189-97. [PMID: 25530438 DOI: 10.1002/jbt.21684] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2014] [Revised: 11/10/2014] [Accepted: 11/15/2014] [Indexed: 01/02/2023]
Abstract
Gap junction intercellular communication is involved in ischemia-reperfusion (IR) injury of organs. Connexins are proteins that are critical to the function of gap junctions. To clarify the role of gap junctions in IR injury in liver cells, the function of gap junctions was modulated in an in vitro hypoxia/reoxygenation (H/R) model. BRL-3A rat liver cells, endogenously expressing connexins Cx32 and Cx43, were used to model the process of hepatic IR injury. Suppression of gap junction activity was achieved genetically, using Cx32-specific small interfering RNA (siRNA), or chemically, with pharmacological inhibitors, oleamide, and 18-α-GA. BRL-3A cells subjected to H/R exhibited reduced cell survival and pathologies indicative of IR injury. Cx32-specific siRNA, oleamide, and 18-α-GA, respectively, decreased gap junction permeability, as assessed by the parachute assay. Pretreatment with Cx32-specific siRNA increased cell survival. Pretreatment with oleamide or 18-α-GA did not improve cell survival. Modulating gap junction by Cx32 gene silencing protected BRL-3A liver cells from H/R.
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Affiliation(s)
- Ren Wang
- Department of Anaesthesiology, The Third Affiliated Hospital, Sun Yat-Sen University, Guangzhou, People's Republic of China.
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24
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Hernández-Guerra M, González-Méndez Y, de Ganzo ZA, Salido E, García-Pagán JC, Abrante B, Malagón AM, Bosch J, Quintero E. Role of gap junctions modulating hepatic vascular tone in cirrhosis. Liver Int 2014; 34:859-68. [PMID: 24350605 DOI: 10.1111/liv.12446] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/06/2013] [Accepted: 12/11/2013] [Indexed: 02/06/2023]
Abstract
BACKGROUND & AIMS Gap junctions are formed by connexins (Cx), a family of proteins that couple endothelial and smooth muscle cells in systemic vessels. In this context, Cx allow the transmission of signals modulating vascular tone. Recently, vascular Cx have been observed in liver cells implicated in liver blood flow regulation. Here, we investigated the role of Cx in the regulation of intrahepatic vascular tone in cirrhosis. METHODS Livers of Sprague-Dawley control and cirrhotic (common bile duct ligation-CBDL and CCl4 ) rats were perfused, and concentration-effect curves in response to acetylcholine (ACh) precontracted with methoxamine were obtained in the presence of the specific Cx inhibitor 18-alpha-glycyrrhetinic acid or vehicle. Cx expression was assessed by immunofluorescence, western blot and reverse-transcription polymerase chain reaction in liver tissue, hepatic stellate cells, sinusoidal endothelial cells and hepatocytes isolated from control and cirrhotic rat livers. Cx protein expression was also determined in cirrhotic human tissue. RESULTS Gap junction blockade markedly attenuated relaxation of hepatic vasculature in response to ACh in control (maximal relaxation, -55 ± 10.5% vs. -95.3 ± 10% with vehicle; P < 0.01) and CBDL rats (50.9 ± 18.5% vs. -18.7 ± 5.5% with vehicle; P = 0.01). Livers from CBDL rats and patients with cirrhosis exhibited Cx overexpression. By contrast, CCl4 -cirrhotic rats did not show attenuated relaxation of hepatic vasculature after blockade and Cx expression was significantly lower than in controls. CONCLUSIONS Gap junctions may contribute to modulating portal pressure and intrahepatic vascular relaxation. Liver gap junctions may represent a new therapeutic target in cirrhotic portal hypertension.
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Affiliation(s)
- Manuel Hernández-Guerra
- Liver Unit, University Hospital of the Canary Islands, Tenerife, Spain; Department of Internal Medicine, University of La Laguna, Tenerife, Spain
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25
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Maes M, Decrock E, Cogliati B, Oliveira AG, Marques PE, Dagli MLZ, Menezes GB, Mennecier G, Leybaert L, Vanhaecke T, Rogiers V, Vinken M. Connexin and pannexin (hemi)channels in the liver. Front Physiol 2014; 4:405. [PMID: 24454290 PMCID: PMC3887319 DOI: 10.3389/fphys.2013.00405] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2013] [Accepted: 12/23/2013] [Indexed: 01/14/2023] Open
Abstract
The liver was among the first organs in which connexin proteins have been identified. Hepatocytes harbor connexin32 and connexin26, while non-parenchymal liver cells typically express connexin43. Connexins give rise to hemichannels, which dock with counterparts on adjacent cells to form gap junctions. Both hemichannels and gap junctions provide pathways for communication, via paracrine signaling or direct intercellular coupling, respectively. Over the years, hepatocellular gap junctions have been shown to regulate a number of liver-specific functions and to drive liver cell growth. In the last few years, it has become clear that connexin hemichannels are involved in liver cell death, particularly in hepatocyte apoptosis. This also holds true for hemichannels composed of pannexin1, a connexin-like protein recently identified in the liver. Moreover, pannexin1 hemichannels are key players in the regulation of hepatic inflammatory processes. The current paper provides a concise overview of the features of connexins, pannexins and their channels in the liver.
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Affiliation(s)
- Michaël Maes
- Department of Toxicology, Center for Pharmaceutical Research, Vrije Universiteit Brussel Brussels, Belgium
| | - Elke Decrock
- Physiology Group, Department of Basic Medical Sciences, Ghent University Ghent, Belgium
| | - Bruno Cogliati
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of Sao Paulo Sao Paulo, Brazil
| | - André G Oliveira
- Department of Morphology, Institute of Biological Sciences, Universidade Federal de Minas Gerais Belo Horizonte, Brazil
| | - Pedro E Marques
- Department of Morphology, Institute of Biological Sciences, Universidade Federal de Minas Gerais Belo Horizonte, Brazil
| | - Maria L Z Dagli
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of Sao Paulo Sao Paulo, Brazil
| | - Gustavo B Menezes
- Department of Morphology, Institute of Biological Sciences, Universidade Federal de Minas Gerais Belo Horizonte, Brazil
| | - Gregory Mennecier
- Department of Pathology, School of Veterinary Medicine and Animal Science, University of Sao Paulo Sao Paulo, Brazil
| | - Luc Leybaert
- Physiology Group, Department of Basic Medical Sciences, Ghent University Ghent, Belgium
| | - Tamara Vanhaecke
- Department of Toxicology, Center for Pharmaceutical Research, Vrije Universiteit Brussel Brussels, Belgium
| | - Vera Rogiers
- Department of Toxicology, Center for Pharmaceutical Research, Vrije Universiteit Brussel Brussels, Belgium
| | - Mathieu Vinken
- Department of Toxicology, Center for Pharmaceutical Research, Vrije Universiteit Brussel Brussels, Belgium
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26
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Inoshita A, Karasawa K, Funakubo M, Miwa A, Ikeda K, Kamiya K. Dominant negative connexin26 mutation R75W causing severe hearing loss influences normal programmed cell death in postnatal organ of Corti. BMC Genet 2014; 15:1. [PMID: 24387126 PMCID: PMC3893426 DOI: 10.1186/1471-2156-15-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2013] [Accepted: 12/30/2013] [Indexed: 12/22/2022] Open
Abstract
Background The greater epithelial ridge (GER) is a developmental structure in the maturation of the organ of Corti. Situated near the inner hair cells of neonatal mice, the GER undergoes a wave of apoptosis after postnatal day 8 (P8). We evaluated the GER from P8 to P12 in transgenic mice that carry the R75W + mutation, a dominant-negative mutation of human gap junction protein, beta 2, 26 kDa (GJB2) (also known as connexin 26 or CX26). Cx26 facilitate intercellular communication within the mammalian auditory organ. Results In both non-transgenic (non-Tg) and R75W + mice, some GER cells exhibited apoptotic characteristics at P8. In the GER of non-Tg mice, both the total number of cells and the number of apoptotic cells decreased from P8 to P12. In contrast, apoptotic cells were still clearly evident in the GER of R75W + mice at P12. In R75W + mice, therefore, apoptosis in the GER persisted until a later stage of cochlear development. In addition, the GER of R75W + mice exhibited morphological signs of retention, which may have resulted from diminished levels of apoptosis and/or promotion of cell proliferation during embryogenesis and early postnatal stages of development. Conclusions Here we demonstrate that Cx26 dysfunction is associated with delayed apoptosis of GER cells and GER retention. This is the first demonstration that Cx26 may regulate cell proliferation and apoptosis during development of the cochlea.
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Affiliation(s)
| | | | | | | | | | - Kazusaku Kamiya
- Department of Otorhinolaryngology, Juntendo University Faculty of Medicine, Hongo 2-1-1, Bunkyo-ku, Tokyo 113-8431, Japan.
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Oliveira AG, Marques PE, Amaral SS, Quintão JLD, Cogliati B, Dagli MLZ, Rogiers V, Vanhaecke T, Vinken M, Menezes GB. Purinergic signalling during sterile liver injury. Liver Int 2013; 33:353-61. [PMID: 23402607 DOI: 10.1111/liv.12109] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2012] [Accepted: 12/28/2012] [Indexed: 12/23/2022]
Abstract
The liver plays a vital role in the organism, and thousands of patients suffer and even die from hepatic complications every year. Viral hepatitis is one of the most important causes of liver-related pathological processes. However, sterile liver diseases, such as drug-induced liver injury, cirrhosis and fibrosis, are still a worldwide concern and contribute significantly to liver transplantation statistics. During hepatocyte death, several genuine intracellular contents are released to the interstitium, where they will trigger inflammatory responses that may boost organ injury. Intracellular purines are key molecules to several metabolic pathways and regulate cell bioenergetics. However, seminal studies in early 70s revealed that purines may also participate in cell-to-cell communication, and more recent data have unequivocally demonstrated that the purinergic signalling plays a key role in the recognition of cell functionality by neighbouring cells and also by the immune system. This new body of knowledge has pointed out that several promising therapeutic opportunities may rely on the modulation of purine release and sensing during diseases. Here, we review the most recent data on the physiological roles of purinergic signalling and how its imbalance may contribute to injury progression during sterile liver injury.
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Affiliation(s)
- André G Oliveira
- Immunobiophotonics Lab, Biological Sciences Institute, Federal University of Minas Gerais, Minas Gerais, Brazil
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28
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Vera-Ramirez L, Pérez-Lopez P, Varela-Lopez A, Ramirez-Tortosa M, Battino M, Quiles JL. Curcumin and liver disease. Biofactors 2013; 39:88-100. [PMID: 23303639 DOI: 10.1002/biof.1057] [Citation(s) in RCA: 90] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/30/2012] [Accepted: 09/13/2012] [Indexed: 12/12/2022]
Abstract
Liver diseases pose a major medical problem worldwide and a wide variety of herbs have been studied for the management of liver-related diseases. In this respect, curcumin has long been used in traditional medicine, and in recent years it has been the object of increasing research interest. In combating liver diseases, it seems clear that curcumin exerts a hypolipidic effect, which prevents the fatty acid accumulation in the hepatocytes that may result from metabolic imbalances, and which may cause nonalcoholic steatohepatitis. Another crucial protective activity of curcumin, not only in the context of chronic liver diseases but also regarding carcinogenesis and other age-related processes, is its potent antioxidant activity, which affects multiple processes and signaling pathways. The effects of curcumin on NF-κβ are crucial to our understanding of the potent hepatoprotective role of this herb-derived micronutrient. Because curcumin is a micronutrient that is closely related to cellular redox balance, its properties and activity give rise to a series of molecular reactions that in every case and biological situation affect the mitochondria.
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Affiliation(s)
- Laura Vera-Ramirez
- GENyO Center Pfizer-University of Granada & Andalusian Government Centre for Genomics & Oncology, Granada, Spain
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