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Helzberg JH, Parish A, Niedzwiecki D, Kim CY, Patel YA, Wilder JM, Muir AJ. Racial disparities in transjugular intrahepatic portosystemic shunt procedure outcomes. BMJ Open Gastroenterol 2022; 9:bmjgast-2021-000747. [PMID: 35086849 PMCID: PMC8796249 DOI: 10.1136/bmjgast-2021-000747] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2021] [Accepted: 12/29/2021] [Indexed: 12/24/2022] Open
Abstract
Objective The transjugular intrahepatic portosystemic shunt (TIPS) procedure is an important intervention for management of complications of portal hypertension. The objective of this study was to identify predictors of mortality from the TIPS procedure with a focus on race and ethnicity. Design TIPS procedures from 2012 to 2014 in the National Inpatient Sample were identified. Weighting was applied to generate nationally representative results. In-hospital mortality was the primary outcome of interest. χ2 and Student’s t-tests were performed for categorical and continuous variables, respectively. Predictors of mortality following TIPS were assessed by survey-weighted logistic regression. Results 17 175 (95% CI 16 254 to 18 096) TIPS cases were identified. Approximately 71% were non-Hispanic (NH) white, 6% were NH black, 16% were Hispanic and 7% were other. NH black patients undergoing TIPS had an in-hospital mortality rate of 20.1%, nearly double the in-hospital mortality of any other racial or ethnic group. NH black patients also had significantly longer median postprocedure and total lengths of stay (p=0.03 and p<0.001, respectively). The interaction of race by clinical indication was a significant predictor of in-hospital mortality (p<0.001). NH black patients had increased mortality compared with other racial/ethnic groups when presenting with bleeding oesophageal varices (OR 3.85, 95% CI 2.14 to 6.95). Conclusion This cohort study presents important findings in end-stage liver disease care, with clear racial disparities in in-hospital outcomes following the TIPS procedure. Specifically, black patients had significantly higher in-hospital mortality and longer lengths of stay. Further research is needed to understand how we can better care for black patients with liver disease.
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Affiliation(s)
- James H Helzberg
- Department of Medicine, Duke University School of Medicine, Durham, North Carolina, USA
| | - Alice Parish
- Department of Biostatistics and Bioinformatics, Duke University School of Medicine, Durham, North Carolina, USA
| | - Donna Niedzwiecki
- Department of Biostatistics and Bioinformatics, Duke University School of Medicine, Durham, North Carolina, USA
| | - Charles Y Kim
- Department of Radiology, Division of Interventional Radiology, Duke University School of Medicine, Durham, North Carolina, USA
| | - Yuval A Patel
- Department of Medicine, Division of Gastroenterology, Duke University School of Medicine, Durham, North Carolina, USA
| | - Julius M Wilder
- Department of Medicine, Division of Gastroenterology, Duke University School of Medicine, Durham, North Carolina, USA.,Duke Clinical Research Institute, Duke University School of Medicine, Durham, North Carolina, USA
| | - Andrew J Muir
- Department of Medicine, Division of Gastroenterology, Duke University School of Medicine, Durham, North Carolina, USA .,Duke Clinical Research Institute, Duke University School of Medicine, Durham, North Carolina, USA
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Li W, Ehrich M. Effects of chlorpyrifos on transient receptor potential channels. Toxicol Lett 2022; 358:100-104. [DOI: 10.1016/j.toxlet.2022.01.016] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 01/19/2022] [Accepted: 01/27/2022] [Indexed: 01/15/2023]
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Quantitative real-time measurement of endothelin-1-induced contraction in single non-activated hepatic stellate cells. PLoS One 2021; 16:e0255656. [PMID: 34343209 PMCID: PMC8330899 DOI: 10.1371/journal.pone.0255656] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2020] [Accepted: 07/21/2021] [Indexed: 12/13/2022] Open
Abstract
Although quiescent hepatic stellate cells (HSCs) have been suggested to regulate hepatic blood flow, there is no direct evidence that quiescent HSCs display contractile abilities. Here, we developed a new method to quantitatively measure the contraction of single isolated HSCs and evaluated whether endothelin-1 (ET-1) induced contraction of HSCs in a non-activated state. HSCs isolated from mice were seeded on collagen gel containing fluorescent beads. The beads around a single HSC were observed gravitating toward the cell upon contraction. By recording the movement of each bead by fluorescent microscopy, the real-time contraction of HSCs was quantitatively evaluated. ET-1 induced a slow contraction of non-activated HSCs, which was inhibited by the non-muscle myosin II inhibitor blebbistatin, the calmodulin inhibitor W-7, and the ETA receptor antagonist ambrisentan. ET-1-induced contraction was also largely reduced in Ca2+-free conditions, but sustained contraction still remained. The tonic contraction was further diminished by the Rho-kinase inhibitor H-1152. The mRNA expression of P/Q-type voltage-dependent Ca2+ channels (VDCC), as well as STIM and Orai, constituents of store-operated channels (SOCs), was observed in mouse non-activated HSCs. ET-1-induced contraction was not affected by amlodipine, a VDCC blocker, whereas it was partly reduced by Gd3+ and amiloride, non-selective cation channel blockers. However, neither YM-58483 nor SKF-96365, which inhibit SOCs, had any effects on the contraction. These results suggest that ET-1 leads to Ca2+-influx through cation channels other than SOCs and produces myosin II-mediated contraction of non-activated HSCs via ETA receptors, as well as via mechanisms involving Ca2+-calmodulin and Rho kinase.
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Orai1 Channel Regulates Human-Activated Pancreatic Stellate Cell Proliferation and TGF β1 Secretion through the AKT Signaling Pathway. Cancers (Basel) 2021; 13:cancers13102395. [PMID: 34063470 PMCID: PMC8156432 DOI: 10.3390/cancers13102395] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 05/04/2021] [Accepted: 05/12/2021] [Indexed: 12/24/2022] Open
Abstract
Simple Summary Activated pancreatic stellate cells (aPSCs), the main source of cancer-associated fibroblasts in pancreatic ductal adenocarcinoma (PDAC), are well known as the key actor of the abundant fibrotic stroma development surrounding the tumor cells. In permanent communication with the tumor cells, they enhance PDAC early spreading and limit the drug delivery. However, the understanding of PSC activation mechanisms and the associated signaling pathways is still incomplete. In this study, we aimed to evaluate the role of Ca2+, and Orai1 Ca2+ channels, in two main PSC activation processes: cell proliferation and cytokine secretion. Indeed, Ca2+ is a versatile second messenger implicated in the regulation of numerous biological processes. We believe that a better comprehension of PSC Ca2+ -dependent activation mechanisms will bring up new crucial PDAC early prognostic markers or new targeting approaches in PDAC treatment. Abstract Activated pancreatic stellate cells (aPSCs), the crucial mediator of pancreatic desmoplasia, are characterized, among others, by high proliferative potential and abundant transforming growth factor β1 (TGFβ1) secretion. Over the past years, the involvement of Ca2+ channels in PSC pathophysiology has attracted great interest in pancreatic cancer research. We, thus, aimed to investigate the role of the Orai1 Ca2+ channel in these two PSC activation processes. Using the siRNA approach, we invalided Orai1 expression and assessed the channel functionality by Ca2+ imaging, the effect on aPSC proliferation, and TGFβ1 secretion. We demonstrated the functional expression of the Orai1 channel in human aPSCs and its implication in the store-operated Ca2+ entry (SOCE). Orai1 silencing led to a decrease in aPSC proliferation, TGFβ1 secretion, and AKT activation. Interestingly, TGFβ1 induced a higher SOCE response by increasing Orai1 mRNAs and proteins and promoted both AKT phosphorylation and cell proliferation, abolished by Orai1 silencing. Together, our results highlight the role of Orai1-mediated Ca2+ entry in human aPSC pathophysiology by controlling cell proliferation and TGFβ1 secretion through the AKT signaling pathway. Moreover, we showed a TGFβ1-induced autocrine positive feedback loop by promoting the Orai1/AKT-dependent proliferation via the stimulation of Orai1 expression and function.
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Li J, Kong L, Huang H, Luan S, Jin R, Wu F. ASIC1a inhibits cell pyroptosis induced by acid-induced activation of rat hepatic stellate cells. FEBS Open Bio 2020; 10:1044-1055. [PMID: 32237041 PMCID: PMC7262943 DOI: 10.1002/2211-5463.12850] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2020] [Revised: 03/11/2020] [Accepted: 03/25/2020] [Indexed: 12/19/2022] Open
Abstract
The activation of hepatic stellate cells (HSCs) is associated with liver fibrosis, the pathological feature of most forms of chronic hepatic damage, and is accompanied by abnormal deposition of the extracellular matrix (ECM). During the pathological process, acid-sensing ion channel 1a (ASIC1a), which is responsible for Ca2+ transportation, is involved in the activation of HSCs. It has previously been identified that ASIC1a is related to pyroptosis in articular chondrocytes. However, it remains unclear whether ASIC1a restrains pyroptosis during liver fibrosis. Here, we determined that the levels of pyroptosis-associated speck-like protein, gasdermin D, caspase-1, nucleotide-binding oligomerization domain (NOD)-like receptor 3, and apoptosis-associated speck-like protein (ASC) decreased, while the level of α-smooth muscle actin and collagen-I increased upon introduction of ASIC1a into an acid-induced model. Inhibition or silencing of ASIC1a and the use of Ca2+ -free medium were able to promote the pyroptosis of activated HSCs, which reduced their deposition. In summary, our study indicates that ASIC1a inhibits pyroptosis of HSCs and that inhibition of ASIC1a may be able to promote pyroptosis to relieve liver fibrosis.
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Affiliation(s)
- Jun Li
- School of PharmacyAnhui Medical UniversityHefeiChina
| | - Lingjin Kong
- School of PharmacyAnhui Medical UniversityHefeiChina
| | - Huiping Huang
- School of PharmacyAnhui Medical UniversityHefeiChina
| | - Shaohua Luan
- School of PharmacyAnhui Medical UniversityHefeiChina
| | - Rui Jin
- School of PharmacyAnhui Medical UniversityHefeiChina
| | - Fanrong Wu
- School of PharmacyAnhui Medical UniversityHefeiChina
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Ali ES, Rychkov GY, Barritt GJ. Deranged hepatocyte intracellular Ca 2+ homeostasis and the progression of non-alcoholic fatty liver disease to hepatocellular carcinoma. Cell Calcium 2019; 82:102057. [PMID: 31401389 DOI: 10.1016/j.ceca.2019.102057] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 06/29/2019] [Accepted: 07/01/2019] [Indexed: 12/12/2022]
Abstract
Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related deaths in men, and the sixth in women. Non-alcoholic fatty liver disease (NAFLD) is now one of the major risk factors for HCC. NAFLD, which involves the accumulation of excess lipid in cytoplasmic lipid droplets in hepatocytes, can progress to non-alcoholic steatosis, fibrosis, and HCC. Changes in intracellular Ca2+ constitute important signaling pathways for the regulation of lipid and carbohydrate metabolism in normal hepatocytes. Recent studies of steatotic hepatocytes have identified lipid-induced changes in intracellular Ca2+, and have provided evidence that altered Ca2+ signaling exacerbates lipid accumulation and may promote HCC. The aims of this review are to summarise current knowledge of the lipid-induced changes in hepatocyte Ca2+ homeostasis, to comment on the mechanisms involved, and discuss the pathways leading from altered Ca2+ homeostasis to enhanced lipid accumulation and the potential promotion of HCC. In steatotic hepatocytes, lipid inhibits store-operated Ca2+ entry and SERCA2b, and activates Ca2+ efflux from the endoplasmic reticulum (ER) and its transfer to mitochondria. These changes are associated with changes in Ca2+ concentrations in the ER (decreased), cytoplasmic space (increased) and mitochondria (likely increased). They lead to: inhibition of lipolysis, lipid autophagy, lipid oxidation, and lipid secretion; activation of lipogenesis; increased lipid; ER stress, generation of reactive oxygen species (ROS), activation of Ca2+/calmodulin-dependent kinases and activation of transcription factor Nrf2. These all can potentially mediate the transition of NAFLD to HCC. It is concluded that lipid-induced changes in hepatocyte Ca2+ homeostasis are important in the initiation and progression of HCC. Further research is desirable to better understand the cause and effect relationships, the time courses and mechanisms involved, and the potential of Ca2+ transporters, channels, and binding proteins as targets for pharmacological intervention.
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Affiliation(s)
- Eunus S Ali
- Department of Medical Biochemistry, College of Medicine and Public Health, Flinders University, Adelaide, South Australia, 5001, Australia
| | - Grigori Y Rychkov
- School of Medicine, The University of Adelaide, and South Australian Health and Medical Research Institute, Adelaide, South Australia, 5005, Australia
| | - Greg J Barritt
- Department of Medical Biochemistry, College of Medicine and Public Health, Flinders University, Adelaide, South Australia, 5001, Australia.
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Chung CC, Lin YK, Chen YC, Kao YH, Yeh YH, Chen YJ. Factor Xa inhibition by rivaroxaban regulates fibrogenesis in human atrial fibroblasts with modulation of nitric oxide synthesis and calcium homeostasis. J Mol Cell Cardiol 2018; 123:128-138. [PMID: 30213724 DOI: 10.1016/j.yjmcc.2018.09.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Revised: 08/19/2018] [Accepted: 09/07/2018] [Indexed: 02/07/2023]
Abstract
BACKGROUND Rivaroxaban, a widely used factor Xa inhibitor in reducing stroke in atrial fibrillation (AF) patients has multiple biological effects with activation of protease-activated receptor (PAR) signaling. Atrial fibrosis plays a critical role in the pathophysiology of AF. In this study, we evaluated whether rivaroxaban regulates atrial fibroblast activity and its underlying mechanisms. METHODS AND RESULTS Migration, proliferation analyses, nitric oxide (NO) production assay, calcium fluorescence imaging, and western blots were conducted in human atrial fibroblasts with or without rivaroxaban (100 nmol/L or 300 nmol/L) and co-administration of L-NAME (L-NG-nitro arginine methyl ester, 100 μmol/L), EGTA (Ethylene glycol tetra-acetic acid, 1 mmol/L), thrombin (0.5 U/mL), PAR1 agonist peptide (TFLLR-NH2, 100 μmol/L), PAR1 inhibitor (SCH79797, 0.5 μmol/L) and PAR2 inhibitor (GB83, 10 μmol/L). Atrial fibrosis was examined in isoproterenol (100 mg/kg, subcutaneous injection)-treated rats with or without rivaroxaban (10 mg/kg/day orally for 14 consecutive days). Rivaroxaban reduced the migration, pro-collagen type I production, and proliferation of atrial fibroblasts. Rivaroxaban decreased phosphorylated endothelial NO synthase (eNOS) (Thr 495, an inhibitory phosphorylated site of eNOS), and calcium (Ca2+) entry, and increased NO production. Moreover, L-NAME blocked the effects of rivaroxaban on fibroblast collagen and NO production. In the presence of EGTA, the migratory capability was similarly decreased in atrial fibroblasts with and without treatment with rivaroxaban (100 nmol/L), which suggests that rivaroxaban decreases migratory capability of atrial fibroblasts by inhibiting Ca2+ entry. Additionally, rivaroxaban significantly attenuated the effects of thrombin, and TFLLR-NH2 on migratory, proliferative, and pro-collagen type I production capability in atrial fibroblasts. SCH79797 or GB83 decreased pro-collagen type I production, migration, and proliferation capability in fibroblasts, but combined SCH79797 or GB83 with and without rivaroxaban had similar fibroblast activity. Moreover, rivaroxaban significantly decreased atrial fibrosis in isoproterenol-treated rats. CONCLUSIONS Rivaroxaban (100-300 nmol/L) regulates atrial fibroblast activity and atrial fibrosis by increasing NO production and decreasing Ca2+ entry through inhibition of PAR signaling.
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Affiliation(s)
- Cheng-Chih Chung
- Division of Cardiology, Department of Internal Medicine, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan; Division of Cardiovascular Medicine, Department of Internal Medicine, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan
| | - Yung-Kuo Lin
- Division of Cardiology, Department of Internal Medicine, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan; Division of Cardiovascular Medicine, Department of Internal Medicine, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan
| | - Yao-Chang Chen
- Department of Biomedical Engineering, National Defense Medical Center, Taipei, Taiwan
| | - Yu-Hsun Kao
- Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan; Department of Medical Education and Research, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan
| | - Yung-Hsin Yeh
- Cardiovascular Department, Chang Gung Memorial Hospital, Linkou, Taiwan; College of Medicine, Chang Gung University, Taoyuan, Taiwan
| | - Yi-Jen Chen
- Division of Cardiology, Department of Internal Medicine, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan; Division of Cardiovascular Medicine, Department of Internal Medicine, Wan Fang Hospital, Taipei Medical University, Taipei, Taiwan; Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan.
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Zhang Y, Zhao X, Chang Y, Zhang Y, Chu X, Zhang X, Liu Z, Guo H, Wang N, Gao Y, Zhang J, Chu L. Calcium channel blockers ameliorate iron overload-associated hepatic fibrosis by altering iron transport and stellate cell apoptosis. Toxicol Appl Pharmacol 2016; 301:50-60. [PMID: 27095094 DOI: 10.1016/j.taap.2016.04.008] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2015] [Revised: 03/24/2016] [Accepted: 04/07/2016] [Indexed: 02/07/2023]
Abstract
Liver fibrosis is the principal cause of morbidity and mortality in patients with iron overload. Calcium channel blockers (CCBs) can antagonize divalent cation entry into renal and myocardial cells and inhibit fibrogenic gene expression. We investigated the potential of CCBs to resolve iron overload-associated hepatic fibrosis. Kunming mice were assigned to nine groups (n=8 per group): control, iron overload, deferoxamine, high and low dose verapamil, high and low dose nimodipine, and high and low dose diltiazem. Iron deposition and hepatic fibrosis were measured in mouse livers. Expression levels of molecules associated with transmembrane iron transport were determined by molecular biology approaches. In vitro HSC-T6 cells were randomized into nine groups (the same groups as the mice). Changes in proliferation, apoptosis, and metalloproteinase expression in cells were detected to assess the anti-fibrotic effects of CCBs during iron overload conditions. We found that CCBs reduced hepatic iron content, intracellular iron deposition, the number of hepatic fibrotic areas, collagen expression levels, and hydroxyproline content. CCBs rescued abnormal expression of α1C protein in L-type voltage-dependent calcium channel (LVDCC) and down-regulated divalent metal transporter-1 (DMT-1) expression in mouse livers. In iron-overloaded HSC-T6 cells, CCBs reduced iron deposition, inhibited proliferation, induced apoptosis, and elevated expression of matrix metalloproteinase-13 (MMP-13) and tissue inhibitor of metalloproteinase-1 (TIMP-1). CCBs are potential therapeutic agents that can be used to address hepatic fibrosis during iron overload. They resolve hepatic fibrosis probably correlated with regulating transmembrane iron transport and inhibiting HSC growth.
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Affiliation(s)
- Ying Zhang
- Department of Pharmacology, Hebei University of Chinese Medicine, Shijiazhuang 050200, Hebei, People's Republic of China; Department of Pathology, Hebei University of Chinese Medicine, Shijiazhuang 050200, Hebei, People's Republic of China; Hebei Key Laboratory of Chinese Medicine Research on Cardio-Cerebrovascular Disease, Shijiazhuang 050200, Hebei, People's Republic of China
| | - Xin Zhao
- Department of Hepatobiliary Surgery, The Third Hospital of Hebei Medical University, Shijiazhuang 050051, Hebei, People's Republic of China
| | - Yanzhong Chang
- Laboratory of Molecular Iron Metabolism, College of Life Science, Hebei Normal University, Shijiazhuang 050024, Hebei, People's Republic of China
| | - Yuanyuan Zhang
- Department of Pharmacology, Hebei University of Chinese Medicine, Shijiazhuang 050200, Hebei, People's Republic of China
| | - Xi Chu
- Department of Pharmacy, The Forth Hospital of Hebei Medical University, Shijiazhuang 050011, Hebei, People's Republic of China
| | - Xuan Zhang
- Department of Pharmacology, Hebei University of Chinese Medicine, Shijiazhuang 050200, Hebei, People's Republic of China
| | - Zhenyi Liu
- Department of Medicinal Chemistry, Hebei University of Chinese Medicine, Shijiazhuang 050200, Hebei, People's Republic of China
| | - Hui Guo
- Department of Medicinal Chemistry, Hebei University of Chinese Medicine, Shijiazhuang 050200, Hebei, People's Republic of China
| | - Na Wang
- Department of Physiology, Hebei University of Chinese Medicine, Shijiazhuang 050200, Hebei, People's Republic of China
| | - Yonggang Gao
- Department of Pharmacology, Hebei University of Chinese Medicine, Shijiazhuang 050200, Hebei, People's Republic of China
| | - Jianping Zhang
- Department of Pharmacology, Hebei University of Chinese Medicine, Shijiazhuang 050200, Hebei, People's Republic of China.
| | - Li Chu
- Department of Pharmacology, Hebei University of Chinese Medicine, Shijiazhuang 050200, Hebei, People's Republic of China; Hebei Key Laboratory of Integrative Medicine on Liver-Kidney Patterns, Shijiazhuang 050200, Hebei, People's Republic of China.
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Sassoli C, Chellini F, Squecco R, Tani A, Idrizaj E, Nosi D, Giannelli M, Zecchi-Orlandini S. Low intensity 635 nm diode laser irradiation inhibits fibroblast-myofibroblast transition reducing TRPC1 channel expression/activity: New perspectives for tissue fibrosis treatment. Lasers Surg Med 2015; 48:318-32. [PMID: 26660509 DOI: 10.1002/lsm.22441] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/28/2015] [Indexed: 12/14/2022]
Abstract
BACKGROUND AND OBJECTIVE Low-level laser therapy (LLLT) or photobiomodulation therapy is emerging as a promising new therapeutic option for fibrosis in different damaged and/or diseased organs. However, the anti-fibrotic potential of this treatment needs to be elucidated and the cellular and molecular targets of the laser clarified. Here, we investigated the effects of a low intensity 635 ± 5 nm diode laser irradiation on fibroblast-myofibroblast transition, a key event in the onset of fibrosis, and elucidated some of the underlying molecular mechanisms. MATERIALS AND METHODS NIH/3T3 fibroblasts were cultured in a low serum medium in the presence of transforming growth factor (TGF)-β1 and irradiated with a 635 ± 5 nm diode laser (continuous wave, 89 mW, 0.3 J/cm(2) ). Fibroblast-myofibroblast differentiation was assayed by morphological, biochemical, and electrophysiological approaches. Expression of matrix metalloproteinase (MMP)-2 and MMP-9 and of Tissue inhibitor of MMPs, namely TIMP-1 and TIMP-2, after laser exposure was also evaluated by confocal immunofluorescence analyses. Moreover, the effect of the diode laser on transient receptor potential canonical channel (TRPC) 1/stretch-activated channel (SAC) expression and activity and on TGF-β1/Smad3 signaling was investigated. RESULTS Diode laser treatment inhibited TGF-β1-induced fibroblast-myofibroblast transition as judged by reduction of stress fibers formation, α-smooth muscle actin (sma) and type-1 collagen expression and by changes in electrophysiological properties such as resting membrane potential, cell capacitance and inwardly rectifying K(+) currents. In addition, the irradiation up-regulated the expression of MMP-2 and MMP-9 and downregulated that of TIMP-1 and TIMP-2 in TGF-β1-treated cells. This laser effect was shown to involve TRPC1/SAC channel functionality. Finally, diode laser stimulation and TRPC1 functionality negatively affected fibroblast-myofibroblast transition by interfering with TGF-β1 signaling, namely reducing the expression of Smad3, the TGF-β1 downstream signaling molecule. CONCLUSION Low intensity irradiation with 635 ± 5 nm diode laser inhibited TGF-β1/Smad3-mediated fibroblast-myofibroblast transition and this effect involved the modulation of TRPC1 ion channels. These data contribute to support the potential anti-fibrotic effect of LLLT and may offer further informations for considering this therapy as a promising therapeutic tool for the treatment of tissue fibrosis.
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Affiliation(s)
- Chiara Sassoli
- Section of Anatomy and Histology, Department of Experimental and Clinical Medicine, University of Florence, Largo Brambilla 3, 50134, Florence, Italy
| | - Flaminia Chellini
- Section of Anatomy and Histology, Department of Experimental and Clinical Medicine, University of Florence, Largo Brambilla 3, 50134, Florence, Italy
| | - Roberta Squecco
- Section of Physiological Sciences, Department of Experimental and Clinical Medicine, University of Florence, Viale GB Morgagni 63, 50134, Florence, Italy
| | - Alessia Tani
- Section of Anatomy and Histology, Department of Experimental and Clinical Medicine, University of Florence, Largo Brambilla 3, 50134, Florence, Italy
| | - Eglantina Idrizaj
- Section of Physiological Sciences, Department of Experimental and Clinical Medicine, University of Florence, Viale GB Morgagni 63, 50134, Florence, Italy
| | - Daniele Nosi
- Section of Anatomy and Histology, Department of Experimental and Clinical Medicine, University of Florence, Largo Brambilla 3, 50134, Florence, Italy
| | - Marco Giannelli
- Odontostomatologic Laser Therapy Center, Via dell' Olivuzzo 162, 50143, Florence, Italy
| | - Sandra Zecchi-Orlandini
- Section of Anatomy and Histology, Department of Experimental and Clinical Medicine, University of Florence, Largo Brambilla 3, 50134, Florence, Italy
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Inhibition of acid-sensing ion channel 1a in hepatic stellate cells attenuates PDGF-induced activation of HSCs through MAPK pathway. Mol Cell Biochem 2014; 395:199-209. [PMID: 24939363 DOI: 10.1007/s11010-014-2125-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2014] [Accepted: 06/02/2014] [Indexed: 12/11/2022]
Abstract
Acid-sensing ion channels (ASICs), a group of Na(+)-selective and Ca(2+)-permeant ligand-gated cation channels, can be transiently activated by extracellular acid. Among seven subunits of ASICs, acid-sensing ion channel 1a (ASIC1a), which is responsible for Ca(2+) transportation, is elevated in response to inflammation, tumor, and ischemic injury in central nervous system and non-neuronal tissues. In this study, we demonstrated for the first time the presence of ASIC1a in rat liver and hepatic stellate cells (HSCs). Furthermore, the expression of ASIC1a was increased in primary HSCs and liver tissues of CCl4-treated rats, suggesting that ASIC1a may play certain role in liver fibrosis. Interestingly, we identified that the level of ASIC1a was significantly elevated in response to platelet-derived growth factor (PDGF) induction in a time- and dose-dependent manner. It was also established that Ca(2+)-transporting ASIC1a was involved in acid-induced injury of different cell types. Moreover, inhibition or silencing of ASIC1a was able to inhibit PDGF-induced pro-fibrogenic effects of activated rat HSCs, including cell activation, de novo synthesis of extracellular matrix components through mitogen-activated protein kinase signaling pathway. Collectively, our studies identified that ASIC1a was expressed in rat liver and HSCs and provided a strong evidence for the involvement of the ASIC1a in the progression of hepatic fibrosis.
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Roles of transient receptor potential canonical (TRPC) channels and reverse-mode Na+/Ca2+ exchanger on cell proliferation in human cardiac fibroblasts: effects of transforming growth factor β1. Cell Calcium 2013; 54:213-25. [PMID: 23827314 DOI: 10.1016/j.ceca.2013.06.005] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2013] [Revised: 06/11/2013] [Accepted: 06/15/2013] [Indexed: 01/27/2023]
Abstract
Expression of transient receptor potential canonical channels (TRPC) and the effects of transforming growth factor-β1 (TGF-β1) on Ca2+ signals and fibroblast proliferation were investigated in human cardiac fibroblasts. The conventional and quantitative real-time RT-PCR, western blot, immunocytochemical analysis, and intracellular Ca2+ concentration [Ca2+]i measurement were applied. Cell proliferation and cell cycle progression were assessed using MTT assays and fluorescence activated cell sorting. Human cardiac fibroblasts have the expression of TRPC1,3,4,6 mRNA and proteins. 1-oleoyl-2-acetyl-sn-glycerol (OAG) and thapsigargin induced extracellular Ca(2+)-mediated [Ca2+]i rise. siRNA for knock down of TRPC6 reduced OAG-induced Ca2+ entry. Hyperforin as well as angiotensin II (Ang II) induced Ca2+ entry. KB-R7943, a reverse-mode Na+/Ca2+ exchanger (NCX) inhibitor, and/or replacement of Na+ with NMDG+ inhibited thapsigargin-, OAG- and Ang II-induced Ca2+ entry. Treatment with TGF-β1 increased thapsigargin-, OAG- and Ang II-induced Ca2+ entry with an enhancement of TRPC1,6 protein expression, suppressed by KB-R7943. TGF-β1 and AngII promoted cell cycle progression from G0/G1 to S/G2/M and cell proliferation. A decrease of the extracellular Ca2+ and KB-R7943 suppressed it. Human cardiac fibroblasts contain several TRPC-mediated Ca2+ influx pathways, which activate the reverse-mode NCX. TGF-β1 enhances the Ca2+ influx pathways requiring Ca2+ signals for its effect on fibroblast proliferation.
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An P, Tian Y, Chen M, Luo H. Ca(2+) /calmodulin- dependent protein kinase II mediates transforming growth factor-β-induced hepatic stellate cells proliferation but not in collagen α1(I) production. Hepatol Res 2012; 42:806-18. [PMID: 22414022 DOI: 10.1111/j.1872-034x.2012.00983.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
AIM Hepatic stellate cells (HSC) are the major players in hepatic fibrosis. As a most potent mitogen, transforming growth factor-β (TGF-β) strongly activates HSC and increases intracellular Ca(2+) concentration. Here, we assessed the potential role of Ca(2+) /calmodulin-dependent protein kinase II (CaMKII), a main downstream effector of the Ca(2+) signal in liver fibrogenesis cascade. METHODS A human immortal HSC cell line, LX-2, and primary rat hepatic stellate cells were used in current study. CaMKII blockage and Akt inhibition were performed by KN-93/CaMKIIα siRNA and LY294002, respectively. HSC proliferation was detected by 5-bromodeoxyuridine incorporation assay. Real-time polymerase chain reaction, western blot and enzyme-linked immunosorbent assay were used to measure mRNA, cellular protein and protein in medium, respectively. Procollagen α1(I) expression was detected by immunocytochemistry. The role of CaMKII on TGF-β/Smad-induced collagen α1(I) expression was determined by (CAGA)(12) -MLP luciferase activity assay. RESULTS TGF-β dramatically increased CaMKII mRNA, and total and phosphorylated CaMKII expression. KN-93 and CaMKIIα siRNA suppressed TGF-β-mediated HSC proliferation. CaMKII interruption blocked TGF-β-elicited Akt activation. LY294002 arrested HSC proliferation and collagen α1(I) production but had no effect on CaMKII. Furthermore, CaMKII led to increased p21 and p27 expression. KN-93 and CaMKIIα siRNA inhibited TGF-β-induced and basal collagen α1(I) production but had no effect on the activity of (CAGA)(12) -MLP luciferase in response to TGF-β stimulation. CONCLUSION CaMKII is a pivotal signal in TGF-β-induced fibrogenic cascades by means of stimulating HSC proliferation, and involved in a basal collagen production. Therefore, CaMKII will be a potentially effective target in the development of therapeutic intervention strategies to attenuate hepatic fibrosis.
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Affiliation(s)
- Ping An
- Division of Gastroenterology, Renmin Hospital of Wuhan University Department of Anatomy and Embryology, Wuhan University School of Medicine, Wuhan, China
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Ohyama T, Sato K, Kishimoto K, Yamazaki Y, Horiguchi N, Ichikawa T, Kakizaki S, Takagi H, Izumi T, Mori M. Azelnidipine is a calcium blocker that attenuates liver fibrosis and may increase antioxidant defence. Br J Pharmacol 2012; 165:1173-87. [PMID: 21790536 DOI: 10.1111/j.1476-5381.2011.01599.x] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND AND PURPOSE Oxidative stress plays a critical role in liver fibrogenesis. Reactive oxygen species (ROS) stimulate hepatic stellate cells (HSCs), and ROS-mediated increases in calcium influx further increase ROS production. Azelnidipine is a calcium blocker that has been shown to have antioxidant effects in endothelial cells and cardiomyocytes. Therefore, we evaluated the anti-fibrotic and antioxidative effects of azelnidipine on liver fibrosis. EXPERIMENTAL APPROACH We used TGF-β1-activated LX-2 cells (a human HSC line) and mouse models of fibrosis induced by treatment with either carbon tetrachloride (CCl(4) ) or thioacetamide (TAA). KEY RESULTS Azelnidipine inhibited TGF-β1 and angiotensin II (Ang II)-activated α1(I) collagen mRNA expression in HSCs. Furthermore, TGF-β1- and Ang II-induced oxidative stress and TGF-β1-induced p38 and JNK phosphorylation were reduced in HSCs treated with azelnidipine. Azelnidipine significantly decreased inflammatory cell infiltration, pro-fibrotic gene expressions, HSC activation, lipid peroxidation, oxidative DNA damage and fibrosis in the livers of CCl(4) - or TAA-treated mice. Finally, azelnidipine prevented a decrease in the expression of some antioxidant enzymes and accelerated regression of liver fibrosis in CCl(4) -treated mice. CONCLUSIONS AND IMPLICATIONS Azelnidipine inhibited TGF-β1- and Ang II-induced HSC activation in vitro and attenuated CCl(4) - and TAA-induced liver fibrosis, and it accelerated regression of CCl(4) -induced liver fibrosis in mice. The anti-fibrotic mechanism of azelnidipine against CCl(4) -induced liver fibrosis in mice may have been due an increased level of antioxidant defence. As azelnidipine is widely used in clinical practice without serious adverse effects, it may provide an effective new strategy for anti-fibrotic therapy.
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Affiliation(s)
- T Ohyama
- Departments of Medicine and Molecular Science Biochemistry, Gunma University Graduate School of Medicine, Maebashi, Gunma, Japan
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14
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Abstract
PURPOSE This study examined the expression and function of inward rectifier K(+) channels in cultured rat hepatic stellate cells (HSC). MATERIALS AND METHODS The expression of inward rectifier K(+) channels was measured using real-time RT-PCR, and electrophysiological properties were determined using the gramicidin-perforated patch-clamp technique. RESULTS The dominant inward rectifier K(+) channel subtypes were K(ir)2.1 and K(ir)6.1. These dominant K(+) channel subtypes decreased significantly during the primary culture throughout activation process. HSC can be classified into two subgroups: one with an inward-rectifying K(+) current (type 1) and the other without (type 2). The inward current was blocked by Ba(2+) (100 microM) and enhanced by high K(+) (140 mM), more prominently in type 1 HSC. There was a correlation between the amplitude of the Ba(2+)-sensitive current and the membrane potential. In addition, Ba(2+) (300 microM) depolarized the membrane potential. After the culture period, the amplitude of the inward current decreased and the membrane potential became depolarized. CONCLUSION HSC express inward rectifier K(+) channels, which physiologically regulate membrane potential and decrease during the activation process. These results will potentially help determine properties of the inward rectifier K(+) channels in HSC as well as their roles in the activation process.
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Affiliation(s)
- Dong Hyeon Lee
- Department of Physiology, College of Medicine, Pochon CHA University, Seongnam, Gyeonggi-do, Korea
| | - In Deok Kong
- Department of Physiology and Institute of Lifelong Health, Yonsei University Wonju College of Medicine, Wonju, Gangwon-do, Korea
| | - Joong-Woo Lee
- Department of Physiology and Institute of Lifelong Health, Yonsei University Wonju College of Medicine, Wonju, Gangwon-do, Korea
| | - Kyu-Sang Park
- Department of Physiology and Institute of Lifelong Health, Yonsei University Wonju College of Medicine, Wonju, Gangwon-do, Korea
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15
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Abstract
The hepatic stellate cell has surprised and engaged physiologists, pathologists, and hepatologists for over 130 years, yet clear evidence of its role in hepatic injury and fibrosis only emerged following the refinement of methods for its isolation and characterization. The paradigm in liver injury of activation of quiescent vitamin A-rich stellate cells into proliferative, contractile, and fibrogenic myofibroblasts has launched an era of astonishing progress in understanding the mechanistic basis of hepatic fibrosis progression and regression. But this simple paradigm has now yielded to a remarkably broad appreciation of the cell's functions not only in liver injury, but also in hepatic development, regeneration, xenobiotic responses, intermediary metabolism, and immunoregulation. Among the most exciting prospects is that stellate cells are essential for hepatic progenitor cell amplification and differentiation. Equally intriguing is the remarkable plasticity of stellate cells, not only in their variable intermediate filament phenotype, but also in their functions. Stellate cells can be viewed as the nexus in a complex sinusoidal milieu that requires tightly regulated autocrine and paracrine cross-talk, rapid responses to evolving extracellular matrix content, and exquisite responsiveness to the metabolic needs imposed by liver growth and repair. Moreover, roles vital to systemic homeostasis include their storage and mobilization of retinoids, their emerging capacity for antigen presentation and induction of tolerance, as well as their emerging relationship to bone marrow-derived cells. As interest in this cell type intensifies, more surprises and mysteries are sure to unfold that will ultimately benefit our understanding of liver physiology and the diagnosis and treatment of liver disease.
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Affiliation(s)
- Scott L Friedman
- Division of Liver Diseases, Mount Sinai School of Medicine, New York, New York 10029-6574, USA.
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16
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Garcia-Tsao G, Sanyal AJ, Grace ND, Carey WD. Prevention and management of gastroesophageal varices and variceal hemorrhage in cirrhosis. Am J Gastroenterol 2007; 102:2086-102. [PMID: 17727436 DOI: 10.1111/j.1572-0241.2007.01481.x] [Citation(s) in RCA: 240] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Guadalupe Garcia-Tsao
- Section of Digestive Diseases, Yale University School of Medicine and VA-CT Healthcare System, New Haven, Connecticut 06520, USA
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17
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Kojima N, Hori M, Murata T, Morizane Y, Ozaki H. Different profiles of Ca2+ responses to endothelin-1 and PDGF in liver myofibroblasts during the process of cell differentiation. Br J Pharmacol 2007; 151:816-27. [PMID: 17533428 PMCID: PMC2014126 DOI: 10.1038/sj.bjp.0707269] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND AND PURPOSE Hepatic stellate cells play an important role in liver fibrosis but little is known about liver myofibroblasts located around the central vein and in the portal area. In this study, intracellular Ca(2+) concentration ([Ca(2+)](i)) was measured to assess the response to endothelin-1 (ET-1), platelet derived growth factor (PDGF) and ATP in rat liver myofibroblasts. EXPERIMENTAL APPROACH Rat liver myofibroblasts were compared in 'quiescent' (cultured on Matrigel-coated dishes) and 'activated' (cultured on non-coated plastic dishes) conditions. [Ca(2+)](i) was measured with the fluorescent dye fura-2 and mRNA for ET-1, PDGF and their receptors by RT-PCR. KEY RESULTS ET-1 increased [Ca(2+)](i) in quiescent cells but not in activated cells, whereas PDGF-BB increased [Ca(2+)](i) in activated cells but not in quiescent cells. However, there was no difference between responses to ATP in quiescent or activated cells. ET-1 (in quiescent cells), PDGF-BB (in activated cells) and ATP (in both cells) all induced transient increases in [Ca(2+)](i) in the absence of extracellular Ca(2+) (with EGTA), indicating the involvement of Ca(2+) release from intracellular Ca(2+) stores. The sustained increase in [Ca(2+)](i) in the presence of external Ca(2+) in activated cells (ATP and PDGF) was significantly reduced by nicardipine, a L-type Ca(2+) channel blocker, but not in quiescent cells (ATP and ET-1). CONCLUSIONS AND IMPLICATIONS The different pharmacological profiles of [Ca(2+)](i)-response in quiescent and activated myofibroblasts suggest that ET-1 and PDGF contribute differently to myofibroblast activation during the process of liver fibrosis.
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Affiliation(s)
- N Kojima
- Department of Veterinary Pharmacology, Graduate School of Agriculture and Life Sciences, The University of Tokyo Bunkyo-ku, Tokyo, Japan
| | - M Hori
- Department of Veterinary Pharmacology, Graduate School of Agriculture and Life Sciences, The University of Tokyo Bunkyo-ku, Tokyo, Japan
| | - T Murata
- Department of Veterinary Pharmacology, Graduate School of Agriculture and Life Sciences, The University of Tokyo Bunkyo-ku, Tokyo, Japan
| | - Y Morizane
- Department of Veterinary Pharmacology, Graduate School of Agriculture and Life Sciences, The University of Tokyo Bunkyo-ku, Tokyo, Japan
| | - H Ozaki
- Department of Veterinary Pharmacology, Graduate School of Agriculture and Life Sciences, The University of Tokyo Bunkyo-ku, Tokyo, Japan
- Author for correspondence:
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18
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Fasulakis S, Rerksuppaphol S, Hardikar W, Vrazas J, Brooks M. Alternative technique for transjugular intrahepatic portosystemic shunt in a young child. ACTA ACUST UNITED AC 2006; 50:447-50. [PMID: 16981941 DOI: 10.1111/j.1440-1673.2006.01621.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Liver transplantation is safer, more readily available and is increasingly being carried out in younger patients. Therapeutic bridging procedures such as transjugular intrahepatic portosystemic shunt have therefore become more relevant to paediatrics, especially in the group of patients who are too unstable for surgery or in whom a liver graft is not available. We describe a transjugular intrahepatic portosystemic shunt procedure in a 4-year-old child with life-threatening variceal bleeding in whom the conventional procedure had failed. This technique may provide an alternative to conventional transjugular intrahepatic portosystemic shunt in this group.
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Affiliation(s)
- S Fasulakis
- Department of Radiology, Royal Children's Hospital, Parkville, Vic, Australia.
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19
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Abstract
Cardiac function is determined by the dynamic interaction of various cell types and the extracellular matrix that composes the heart. This interaction varies with the stage of development and the degree and duration of mechanical, chemical, and electrical signals between the various cell types and the ECM. Understanding how these complex signals interact at the molecular, cellular, and organ levels is critical to understanding the function of the heart under a variety of physiological and pathophysiological conditions. Quantitative approaches, both in vivo and in vitro, are essential to understand the dynamic interaction of mechanical, chemical, and electrical stimuli that govern cardiac function. The fibroblast can thus be a friend in normal function or a foe in pathophysiological conditions.
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Affiliation(s)
- Troy A Baudino
- Department of Cell and Developmental Biology and Anatomy, School of Medicine, University of South Carolina, Columbia, SC 29208, USA
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20
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Melton AC, Datta A, Yee HF. [Ca2+]i-independent contractile force generation by rat hepatic stellate cells in response to endothelin-1. Am J Physiol Gastrointest Liver Physiol 2006; 290:G7-13. [PMID: 16123199 DOI: 10.1152/ajpgi.00337.2005] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The contractile force generated by hepatic stellate cells in response to endothelin-1 contributes to sinusoidal blood flow regulation and hepatic fibrosis. This study's aim was to directly test the widely held view that changes in cytosolic Ca2+ concentration ([Ca2+]i) mediate stellate cell force generation. Contractile force generation by primary cultures of rat hepatic stellate cells grown in three-dimensional collagen gels was directly and quantitatively measured using a force transducer. Stellate cell [Ca2+]i, myosin activation, and migration were quantified using standard techniques. [Ca2+]i was modulated using ionomycin, BAPTA, KCl, and removal of extracellular Ca2+. Removal of extracellular Ca2+ did not alter endothelin-1-stimulated force development or [Ca2+]i. Ionomycin, a Ca2+ ionophore, triggered an increase in [Ca2+]i that was three times greater than that stimulated by endothelin-1, but only induced 16% of the force and 38% of the myosin regulatory light chain (MLC) phosphorylation induced by endothelin-1. Physiological increases in [Ca2+]i induced by hyperkalemia had no effect on contractile force. Loading BAPTA, a Ca2+ chelator, in stellate cells completely blocked endothelin-1-induced increases in [Ca2+]i but had no effect on endothelin-1-stimulated force generation or MLC phosphorylation. In contrast, Y-27632, a selective rho-associated kinase inhibitor, inhibited endothelin-1-stimulated force generation by at least 70% and MLC phosphorylation by at least 80%. Taken together, these observations indicate that changes in [Ca2+]i are neither necessary nor sufficient for contractile force generation by rat stellate cells. Our results challenge the current model of contractile regulation in hepatic stellate cells and have important implications for our understanding of hepatic pathophysiology.
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Affiliation(s)
- Andrew C Melton
- Liver Center and Department of Medicine, University of San Francisco, San Francisco General Hospital, Bldg. 40, Rm. 4102, 1001 Potrero Ave., San Francisco, CA 94110, USA
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Membreno F, Baez AL, Pandula R, Walser E, Lau DTY. Differences in long-term survival after transjugular intrahepatic portosystemic shunt for refractory ascites and variceal bleed. J Gastroenterol Hepatol 2005; 20:474-81. [PMID: 15740494 DOI: 10.1111/j.1440-1746.2005.03601.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
OBJECTIVE To compare the survival after transjugular intrahepatic portosystemic shunt (TIPS) for refractory ascites and variceal bleed, and to identify the factors predictive of survival. METHODS Single tertiary center, retrospective-prospective study. Chart review was performed on all patients who underwent TIPS between 1993 and 2000 and prospective follow-up to determine survival. Pre- and post-TIPS clinical parameters were compared and Kaplan-Meier analysis was applied to compare the survival of both groups. Cox regression was used to identify predictors of survival after TIPS. RESULTS A total of 163 patients were included, 62 with refractory ascites and 101 with variceal bleed. Both groups had similar age (48.2 vs 48.9 year; P = 0.65) and consisted of predominantly Caucasians (51%) and Mexican-Americans (39%). More than 75% had chronic hepatitis C, alcoholic liver disease or both. Overall, the median survival was significantly better for variceal bleed (2 years) compared with refractory ascites (6 months) (P < 0.001). This survival advantage persisted in patients with Mayo risk score greater than 1.17. Transjugular intrahepatic portosystemic shunt improved severe ascites in 45% of patients (P = 0.03). Mayo risk score was highly predictive of survival after TIPS with a hazard ratio of 2.3, followed by Child-Pugh score, creatinine, albumin and ethnicity, with better survival among Mexican-Americans. Shunt dysfunction (31%) and hepatic encephalopathy (27%) were the most common complications of TIPS. CONCLUSIONS Patients who received TIPS for variceal bleed had significantly longer survival compared with those for refractory ascites. Mexican-Americans had an improved long-term survival compared with Caucasians. The reason for this ethnic difference in survival is unclear and warrants further prospective evaluation.
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Affiliation(s)
- Fernando Membreno
- Department of Internal Medicine, The University of Texas Medical Branch of Galveston, Texas, USA
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22
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Abstract
Hepatic cirrhosis is a common disease that poses a serious threat to public health, and is characterized by chronic, progressive and diffuse hepatic lesions preceded by hepatic fibrosis regardless of the exact etiologies. In recent years, considerable achievements have been made in China in research of the etiopathogenesis, diagnosis and especially the treatment of hepatic fibrosis, resulting in much improved prognosis of hepatic fibrosis and cirrhosis. In this paper, the authors review the current status of research in hepatic fibrosis, cirrhosis and their major complications.
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Affiliation(s)
- Xi-Xian Yao
- Department of Gastroenterology of Internal Medicine, Second Hospital, Hebei Medical University, Shijiazhuang 050000, Hebei Province, China.
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23
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Abstract
BACKGROUND Secondary prophylaxis for esophageal variceal hemorrhage (VH) is recommended, but there has never been a cost-utility analysis of its implementation. OBJECTIVE The objective was to compare the cost utility of various strategies for the secondary prophylaxis of VH including (a) observation alone, (b) medical therapy (MED), (c) endoscopic band ligation (EBL), (d) endoscopic band ligation plus medical therapy (EBL + M), and (e) transjugular intrahepatic portosystemic shunt (TIPS), and to examine the effect of adherence on these strategies. METHODS A Markov model was developed for all five strategies, and included surveillance, risk of hepatic encephalopathy, complications, and nonadherence. DATA SOURCES Published literature and the Health Care Financing Administration. TARGET POPULATION People with cirrhosis and a history of controlled VH. TIME HORIZON Three years. PERSPECTIVE Third-party payer. OUTCOME MEASURES Incremental cost-effectiveness ratios for quality-adjusted life-years (QALYs) gained. RESULTS OF BASE-CASE ANALYSIS Combination EBL + M was the optimal strategy, dominating all other strategies including observation, meaning that it was more effective and less expensive than the others. In addition, EBL alone dominated observation and TIPS in terms of QALYs, and MED alone dominated the strategy of observation in terms of QALYs. RESULTS OF SENSITIVITY ANALYSIS Important variables affecting the optimal strategy were the odds ratio (OR) of VH with EBL compared to MED, the OR of VH with EBL + M compared to EBL, and patients' preferences regarding taking the medication as reflected in the associated toll exacted on the health state utility. Variations in these parameters within the range of clinical plausibility allowed EBL or MED to become the optimal strategy. TIPS was the optimal strategy only if adherence rates for all strategies were less than 12%. RESULTS OF MONTE CARLO ANALYSIS: Neither observation nor TIPS was ever the optimal strategy, and EBL + M was optimal in 62% of cases. If the variables identified in the sensitivity analysis were controlled, then EBL + M was optimal in 95% of cases. CONCLUSIONS TIPS should be reserved only for patients with very poor adherence. Otherwise, patients are best served by medications, EBL, or a combination of both, depending on the comparative rates of rebleeding with each and patients' preferences regarding medical therapy. The redundancy of combination band ligation plus medical therapy can improve outcomes, particularly in the setting of poor patient adherence.
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Affiliation(s)
- Joel H Rubenstein
- Division of Gastroenterology, University of Michigan Health System, Ann Arbor, Michigan 48109-0362, USA
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Schepke M, Roth F, Fimmers R, Brensing KA, Sudhop T, Schild HH, Sauerbruch T. Comparison of MELD, Child-Pugh, and Emory model for the prediction of survival in patients undergoing transjugular intrahepatic portosystemic shunting. Am J Gastroenterol 2003; 98:1167-74. [PMID: 12809844 DOI: 10.1111/j.1572-0241.2003.07515.x] [Citation(s) in RCA: 141] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVES Recently, new prognostic models (Model for End-Stage Liver Disease [MELD model] and Emory score) were proposed for the prediction of survival in transjugular intrahepatic portosystemic shunt (TIPS) patients. Although the MELD model is considered to be superior and has consecutively been applied to priority listing for liver transplantation, these models have never been directly compared in terms of long-term prognosis. We therefore compared the prognostic accuracy of the different models, including the Child-Pugh score, in an unselected cohort of TIPS patients followed long-term. METHODS Baseline risk scores for 162 unselected consecutive TIPS patients followed until death (n = 81), liver transplantation, or end of observation (n = 81) (mean follow-up 30.7 +/- 26.4 months) were calculated, and respective concordance- (c-)statistics for the predictive accuracy of 3-, 12-, and 36-month survival for the three models were compared statistically. RESULTS All three models predicted short-term (3-month) survival with similar accuracy. The MELD model generated the best c-statistics for both 12-month (c-statistic 0.73, 95% CI = 0.64-0.82) and 36-month survival (c-statistic 0.74, 95% CI = 0.64-0.84). The predictive accuracy of the Emory score was significantly lower (c-statistic for 12-month survival: 0.60, 95% CI = 0.52-0.68, p = 0.012 vs MELD). In the statistical comparison of the MELD and the Child-Pugh model, only a trend favoring MELD for the prediction of 1-yr survival in patients with intestinal bleeding could be observed (MELD: c-statistic 0.78, 95% CI = 0.67-0.89; Child-Pugh: c-statistic 0.67, 95% CI = 0.55-0.80, p = 0.059). CONCLUSIONS The MELD model is superior to the Emory score but only slightly superior to the Child-Pugh classification for the prediction of long-term survival in TIPS patients.
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Affiliation(s)
- Michael Schepke
- Department of Internal Medicine I, University of Bonn, Bonn, Germany
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25
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Yang WL, Tripathi D, Therapondos G, Todd A, Hayes PC. Endoscopic use of human thrombin in bleeding gastric varices. Am J Gastroenterol 2002; 97:1381-5. [PMID: 12094854 DOI: 10.1111/j.1572-0241.2002.05776.x] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVE The management of gastric variceal hemorrhage remains a clinical challenge. Bovine thrombin has been reported to be effective in two small series. We report our experience with human thrombin in the treatment of bleeding gastric varices. METHODS We reviewed the case records of 12 patients presenting over a 2-yr period with gastric variceal bleeding requiring endoscopic injection of human thrombin. Ten were male and the mean age was 52 yr (range = 26-83). The underlying diagnoses were cirrhosis in nine, portal vein thrombosis in two, and liver metastasis in one. The majority had fundal gastric varices, and none were thought to have bled from their esophageal varices. Eight received thrombin as primary treatment, whereas four had thrombin only after failing transjugular intrahepatic portosystemic shunts. Patients received one to four sessions (mean = 1.9) of thrombin with a mean total dose of 1833 U (range = 800-4000). Mean follow-up was 17.8 months for those still alive (range = 7-33). RESULTS Hemostasis in the acute setting was successful in nine patients all of whom received thrombin within 48 hours of the bleed. In the longer term, nine of the 12 had no further bleeding. Of these, five patients did well with thrombin alone, one died of cancer, and the other three went on electively to more definitive shunt procedures. Three patients rebled from their gastric varices of which one was successfully retreated with thrombin. Only one death was related to variceal bleeding (8%). No adverse reactions were noted. CONCLUSION Our experience demonstrates that endoscopic therapy with thrombin appears safe and can be effective in the management of gastric variceal bleeding.
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Affiliation(s)
- Wei Lyn Yang
- Centre for Liver and Digestive Disorders, Department of Medicine, Royal Infirmary of Edinburgh, United Kingdom
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26
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Abstract
Important advances have been made in the management of variceal bleeding. Despite these advances, bleeding in the patient with cirrhosis remains one of the most demanding clinical challenges that a gastroenterologist or gastrointestinal surgeon may face. The aim is to identify the source of bleeding, control active bleeding and prevent rebleeding. This requires a multidisciplinary team, and the optimal management algorithm depends on the clinical circumstance of the patient and the local availability of endoscopic, radiological and surgical expertise. Injection sclerotherapy is effective in stopping acute variceal bleeding, but has the drawback of a high incidence of complications. Endoscopic variceal ligation is just as effective, and is associated with fewer complications. An overtube allows repeated introductions of the endoscope to be more tolerable for the patient and protects the airway against aspiration of blood; its use should be encouraged in patients with massive bleeding. Newer ligators can deliver multiple bands without removal of the scope but the high cost of these disposable devices limits their widespread use. Bleeding from gastric varices is even more challenging; the treatment of choice is injection with cyanoacrylate glue. To prevent rebleeding, beta-blockers are recommended for all patients with large varices (including those which have never bled). Injection sclerotherapy or band ligation, conducted at weekly intervals after the initial control of bleeding, is equally effective at obliterating varices and decreasing the risk of further hemorrhage; band ligation results in fewer complications. Other newer treatment modalities for variceal bleeding, such as somatostatin analogs, transjugular intrahepatic portasystemic shunt and liver transplantation, offer more optimal approaches to control bleeding and prevent rebleeding, but may be prohibitively expensive. Even for the most affluent communities, affordability, cost-effectiveness, and resource rationing are important considerations in management of patients with cirrhosis complicated by gastrointestinal bleeding.
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Affiliation(s)
- Sydney Chung
- Endoscopy Centre, The Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong, China.
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27
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Singh P, Pooran N, Indaram A, Bank S. Combined ligation and sclerotherapy versus ligation alone for secondary prophylaxis of esophageal variceal bleeding: a meta-analysis. Am J Gastroenterol 2002; 97:623-9. [PMID: 11922557 DOI: 10.1111/j.1572-0241.2002.05540.x] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVES Variceal ligation has been shown to be superior to sclerotherapy in prevention of rebleeding and improving survival in patients with cirrhosis. However, 25% of patients will rebleed before completion of treatment. A number of trials have compared the combination of ligation and sclerotherapy to ligation alone in achieving rapid and complete eradication of esophageal varices, with conflicting results. METHODS Two reviewers independently identified seven randomized, controlled trials that compared endoscopic variceal ligation with the combination of sclerotherapy and ligation for the treatment of esophageal varices. Studies were identified by searching MEDLINE, reviewing references from retrieved articles, and scanning abstracts from conference proceedings. For each outcome, odds ratios (ORs) were calculated using fixed-effects and random-effects models. The Mantel-Haenszel test for statistical heterogeneity was used to assess the validity of combining results from individual studies. RESULTS No significant difference was seen in cessation of actively bleeding varices (OR = 1.01, 95% CI = 0.43-2.36), variceal rebleeding (OR = 1.12, CI = 0.69-1.81), and mortality (OR = 1.1, CI = 0.70-1.74) in patients with variceal ligation versus patients receiving the combination treatment of ligation and sclerotherapy. Treatment sessions required to achieve complete variceal eradication were similar in the two treatment arms. A significantly higher incidence of esophageal stricture was seen in combination therapy (p < 0.001). CONCLUSIONS The combination of ligation and sclerotherapy offers no advantage over ligation alone in prevention of rebleeding and in reduction of mortality. It is also associated with a higher complication rate of esophageal stricture.
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Affiliation(s)
- Pankaj Singh
- Division of Biostatistics, Mailman School of Public Health, Columbia University, New York, New York, USA
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Delhaye M, Le Moine O, Degraef C, Devière J, Galand P. Prognostic value of hepatocyte proliferative activity after transjugular intrahepatic portosystemic shunt. Am J Gastroenterol 2001; 96:1866-71. [PMID: 11419841 DOI: 10.1111/j.1572-0241.2001.03885.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVES Previous data indicated that the proliferating cell nuclear antigen-labeling index (PCNA-LI) reflects the liver functional reserve in human liver cirrhosis. The aim of the study was to evaluate the hepatocyte proliferative activity as a marker for the outcome of patients after transjugular intrahepatic portosystemic shunt (TIPS). METHODS Twenty-eight consecutive patients were electively treated with TIPS for recurrent variceal bleeding (n = 14), refractory ascites (n = 12), or hydrothorax (n = 2). PCNA immunostaining was analyzed on methanol-fixed, paraffin-embedded liver biopsies. RESULTS After TIPS, six patients died within the first 3 months, eight other patients died later, two were transplanted, and 12 were alive at the time of analysis. Early death occurred in patients with refractory ascites (5/12) and/or in Child C patients (3/6). Among the evaluated variables, there was a statistical trend for the PCNA-LI to be lower in patients who died early after TIPS than in those having long term survival (1.55% vs 2.65%, p = 0.07). After TIPS insertion, the probability of remaining alive during the first 6 months of follow-up was significantly higher in patients with a preprocedural PCNA-LI > 2.9%. CONCLUSIONS The PCNA-LI measured on liver biopsy before the TIPS procedure might be a pre-TIPS marker to discriminate those patients for whom TIPS is likely to be beneficial.
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Affiliation(s)
- M Delhaye
- Department of Gastroenterology, Erasme Hospital, Brussels, Belgium
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Bouillier H, Samain E, Miserey S, Perret C, Renaud JF, Safar M, Dagher G. Transforming growth factor-beta1 modulates angiotensin II-induced calcium release in vascular smooth muscle cells from spontaneously hypertensive rats. J Hypertens 2000; 18:733-42. [PMID: 10872558 DOI: 10.1097/00004872-200018060-00011] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVES To investigate the role of transforming growth factor-beta1 (TGF-beta1) on Ca2+-dependent mechanisms elicited by angiotensin II in aortic vascular smooth muscle cells (VSMC) of Wistar- Kyoto (WKY) rats and spontaneously hypertensive rats (SHR). METHODS Cai2+ release induced by angiotensin II (1 micromol/ l) was studied in cultured VSMC isolated from the aortas of 6-week-old WKY rats and SHR. Intracellular Ca2+ (Cai2+) was assessed in Fura-2 loaded cells using fluorescent imaging microscopy. Angiotensin II receptors were analysed by binding studies. RESULTS Pretreatment of VSMC for 24 h with TGF-beta1 significantly increased angiotensin II-induced Cai2+ mobilization from internal stores in SHR, while Ca2+ influx was not altered. This effect involves tyrosine kinase and is not due to an increase in angiotensin II binding sites, or a change in the affinity of the receptors. By contrast, TGF-beta1 did not modify the response of VSMC from WKY rats to angiotensin II. CONCLUSIONS These results help our understanding of the interactions between the pathways activated by TGF-beta1 and the G protein-coupled receptor signalling pathway, and their role in genetic hypertension.
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Affiliation(s)
- H Bouillier
- INSERM U337, Facultè Broussais-Hotel Dieu, Paris, France
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