45 results on '"Lawless MW"'
Search Results
2. Early viral and peripheral blood mononuclear cell responses to pegylated interferon and ribavirin treatment: the first 24 h.
- Author
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Devitt E, Lawless MW, Sadlier D, Browne JA, Walsh C, Crowe J, Devitt, Emma, Lawless, Matthew W, Sadlier, Denise, Browne, John A, Walsh, Caroline, and Crowe, John
- Published
- 2010
- Full Text
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3. Z alpha1-antitrypsin polymerizes in the lung and acts as a neutrophil chemoattractant.
- Author
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Mulgrew AT, Taggart CC, Lawless MW, Greene CM, Brantly ML, O'Neill SJ, McElvaney NG, Mulgrew, Alan T, Taggart, Clifford C, Lawless, Matthew W, Greene, Catherine M, Brantly, Mark L, O'Neill, Shane J, and McElvaney, Noel G
- Abstract
Background: Alpha1-antitrypsin (A1AT) is an abundant protein that is synthesized in the liver and is secreted into the plasma. From the plasma, A1AT diffuses into various body compartments, including the lung where it provides much of the antiprotease protection. The current understanding of the pathogenesis of emphysema in A1AT-deficient individuals focuses on the polymerization of mutant protein within the liver, which results in a deficiency of circulating A1AT and a protease-antiprotease imbalance in the lungs.Methods and Results: In this study, we evaluated BAL fluid samples from five healthy volunteers, five individuals with ZA1AT deficiency, and an individual with the PiZZ phenotype who had received a liver transplant. We show that the lung itself is a source of A1AT. In addition, the Z protein formed in the lung polymerizes, and these polymers are detectable in lung epithelial lining fluid by enzyme-linked immunosorbent assay and Western blot analysis. Finally, we show that polymeric ZA1AT is a potent neutrophil chemoattractant that is similar to polymerized MA1AT.Conclusions: Our findings suggest that the polymerization of locally produced ZA1AT is a contributory factor to the lung inflammation experienced by those with A1AT deficiency and that standard antiprotease therapies may not address this problem. [ABSTRACT FROM AUTHOR]- Published
- 2004
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4. Massive pelvis injuries treated with amputations: case reports and literature review.
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Lawless MW, Laughlin RT, Wright DG, Lemmon GW, and Rigano WC
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- 1997
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5. Unmasking the pathological and therapeutic potential of histone deacetylases for liver cancer.
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Zhao J, Gray SG, Greene CM, and Lawless MW
- Subjects
- Acetylation, Animals, Antineoplastic Agents therapeutic use, Carcinoma, Hepatocellular drug therapy, Carcinoma, Hepatocellular genetics, Carcinoma, Hepatocellular pathology, Epigenesis, Genetic, Gene Expression Regulation, Neoplastic, Histone Deacetylase Inhibitors therapeutic use, Histone Deacetylases genetics, Humans, Liver Neoplasms drug therapy, Liver Neoplasms genetics, Liver Neoplasms pathology, Protein Processing, Post-Translational, RNA, Untranslated genetics, RNA, Untranslated metabolism, Signal Transduction, Carcinoma, Hepatocellular enzymology, Histone Deacetylases metabolism, Histones metabolism, Liver Neoplasms enzymology
- Abstract
Introduction: Hepatocellular carcinoma (HCC) is the most common form of primary liver cancer, currently ranking as one of the highest neoplastic-related mortalities in the world. Due to the difficulty in early diagnosis and lack of effective treatment options, the 5-year survival rate of HCC remains extremely low. Histone deacetylation is one of the most important epigenetic mechanisms, regulating cellular events such as differentiation, proliferation and cell cycle. Histone deacetylases (HDACs), the chief mediators of this epigenetic mechanism, are often aberrantly expressed in various tumours including HCC. Areas covered: This review focuses on the most up-to-date findings of HDACs and their associated molecular mechanisms in HCC onset and progression. In addition, a potential network between HDACs and non-coding RNAs including microRNAs and long noncoding RNAs underlying hepatocarcinogenesis is considered. Expert opinion: Unmasking the role of HDACs and their association with HCC pathogenesis could have implications for future personalized therapeutic and diagnostic targeting.
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- 2019
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6. Antiviral activity of bone morphogenetic proteins and activins.
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Eddowes LA, Al-Hourani K, Ramamurthy N, Frankish J, Baddock HT, Sandor C, Ryan JD, Fusco DN, Arezes J, Giannoulatou E, Boninsegna S, Chevaliez S, Owens BMJ, Sun CC, Fabris P, Giordani MT, Martines D, Vukicevic S, Crowe J, Lin HY, Rehwinkel J, McHugh PJ, Binder M, Babitt JL, Chung RT, Lawless MW, Armitage AE, Webber C, Klenerman P, and Drakesmith H
- Subjects
- Antiviral Agents metabolism, Cells, Cultured, Endopeptidases genetics, Hepacivirus drug effects, Hepatitis C drug therapy, Hepatitis C metabolism, Hepcidins genetics, Humans, Interferon Regulatory Factors genetics, Interferon-alpha pharmacology, Interferon-alpha therapeutic use, RNA, Viral metabolism, Signal Transduction genetics, Smad1 Protein genetics, Ubiquitin Thiolesterase, Virus Replication drug effects, Zika Virus drug effects, Activins pharmacology, Antiviral Agents pharmacology, Bone Morphogenetic Protein 6 pharmacology, Gene Expression Regulation drug effects, Signal Transduction drug effects
- Abstract
Understanding the control of viral infections is of broad importance. Chronic hepatitis C virus (HCV) infection causes decreased expression of the iron hormone hepcidin, which is regulated by hepatic bone morphogenetic protein (BMP)/SMAD signalling. We found that HCV infection and the BMP/SMAD pathway are mutually antagonistic. HCV blunted induction of hepcidin expression by BMP6, probably via tumour necrosis factor (TNF)-mediated downregulation of the BMP co-receptor haemojuvelin. In HCV-infected patients, disruption of the BMP6/hepcidin axis and genetic variation associated with the BMP/SMAD pathway predicted the outcome of infection, suggesting that BMP/SMAD activity influences antiviral immunity. Correspondingly, BMP6 regulated a gene repertoire reminiscent of type I interferon (IFN) signalling, including upregulating interferon regulatory factors (IRFs) and downregulating an inhibitor of IFN signalling, USP18. Moreover, in BMP-stimulated cells, SMAD1 occupied loci across the genome, similar to those bound by IRF1 in IFN-stimulated cells. Functionally, BMP6 enhanced the transcriptional and antiviral response to IFN, but BMP6 and related activin proteins also potently blocked HCV replication independently of IFN. Furthermore, BMP6 and activin A suppressed growth of HBV in cell culture, and activin A inhibited Zika virus replication alone and in combination with IFN. The data establish an unappreciated important role for BMPs and activins in cellular antiviral immunity, which acts independently of, and modulates, IFN.
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- 2019
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7. Improved Early Postoperative Range of Motion in Total Knee Arthroplasty Using Tranexamic Acid: A Retrospective Analysis.
- Author
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Dorweiler MA, Boin MA, Froehle AW, Lawless MW, and May JH
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- Blood Loss, Surgical prevention & control, Case-Control Studies, Edema prevention & control, Female, Hemarthrosis prevention & control, Humans, Male, Middle Aged, Postoperative Complications prevention & control, Postoperative Period, Retrospective Studies, Antifibrinolytic Agents therapeutic use, Arthroplasty, Replacement, Knee, Range of Motion, Articular, Tranexamic Acid therapeutic use
- Abstract
The use of tranexamic acid (TXA) in total knee arthroplasty (TKA) has become common practice. Recent literature has demonstrated a reduction in postoperative knee swelling and drain output while using TXA. Our purpose is to analyze the range of motion (ROM) following TKA in patients who received TXA compared with a control group. We hypothesize that patients treated with TXA will have improved early postoperative ROM when compared with controls. A retrospective chart review was performed for patients who underwent TKA from 2010 to 2012 performed by a single orthopaedic surgeon. Patients were stratified into three cohorts by route of TXA administration including intravenous (IV), topical, and a control group. Dependent variables analyzed included extension, flexion, and total arc ROM on each postoperative day (POD), average ROM across all three postoperative days, as well as pre-to-postoperative differences in ROM. Demographic data were recorded for each patient. A total of 174 patients were included for analysis, 75 controls and 99 receiving TXA. A significant difference was found between the treatment groups and the control for all variables (for each, p ≤ 0.002). There were no significant differences in ROM between the IV and topical TXA treatment groups (for each, p ≥ 0.558). A multivariate analysis demonstrated no significant difference between the groups in complication rate or demographic variables. The use of TXA may improve early postoperative ROM following TKA., Competing Interests: None., (Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.)
- Published
- 2019
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8. The therapeutic properties of resminostat for hepatocellular carcinoma.
- Author
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Zhao J, Gray SG, Wabitsch M, Greene CM, and Lawless MW
- Abstract
Hepatocellular carcinoma (HCC) is the most common form of primary liver cancer with increases in new cases being reported annually. Histopathologists have identified hepatic steatosis as a characteristic of a broad range of chronic liver diseases that are associated with the onset and development of HCC. In this context, epigenetic modifications may serve as precancerous factors predisposing normal cells to the initiation of carcinogenesis. This study demonstrated that hepatic tumorigenesis and differentiated adipocytes may modulate both global histone deacetylase (HDAC) expression and specific class I HDAC genes in the tumour microenvironment. The novel class I HDAC inhibitor Resminostat was shown to reduce the proliferation of HCC cells along with its specificity in targeting class I HDACs and oncogenes. The combined effect of Resminostat with several pharmaceutical agents such as Sorafenib, Cisplatin and Doxorubicin was also demonstrated. The inhibition of heat shock protein 90 (HSP90) has been demonstrated as a potential therapeutic option for HCC. In line with this, the specific HSP90 inhibitor 17-(allylamino)-17-demethoxygeldanamycin (17-AAG) was selected and it was found that the combination of Resminostat and 17-AAG may provide a "smart" clinical strategy for HCC patients by targeting cellular communication within the tumour microenvironment. This study provides an insight into the use of Resminostat as an epigenetic based therapeutic for HCC along with other pharmaceutical options, in particular by targeting the cell-to-cell communication that occurs between hepatoma and adipocytes., Competing Interests: CONFLICTS OF INTEREST The authors declare no potential conflicts of interest.
- Published
- 2018
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9. The Assessment of Blood Loss During Total Knee Arthroplasty When Comparing Intravenous vs Intracapsular Administration of Tranexamic Acid.
- Author
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May JH, Rieser GR, Williams CG, Markert RJ, Bauman RD, and Lawless MW
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- Administration, Intravenous, Aged, Arthroplasty, Replacement, Knee statistics & numerical data, Blood Loss, Surgical statistics & numerical data, Blood Transfusion statistics & numerical data, Female, Humans, Injections, Intra-Articular, Length of Stay, Male, Middle Aged, Postoperative Hemorrhage etiology, Postoperative Period, Antifibrinolytic Agents administration & dosage, Arthroplasty, Replacement, Knee adverse effects, Blood Loss, Surgical prevention & control, Postoperative Hemorrhage prevention & control, Tranexamic Acid administration & dosage
- Abstract
Background: Administration of tranexamic acid topically and intravenously has demonstrated effectiveness in decreasing blood loss and transfusion rates., Methods: We randomized 131 patients undergoing primary total knee arthroplasty to receive either intracapsular (69) or intravenous tranexamic acid (62). Postoperative blood loss was calculated using the formula derived by Nadler et al. The number of units transfused was recorded, as well as length of hospital stay., Results: We found no statistically significant difference on calculated blood loss (postoperative day [POD] 1: 624 ± 326 vs 644 ± 292; P = .71, POD 2: 806 ± 368 vs 835 ± 319; P = .64, and POD 3: 1076 ± 419 vs 978 ± 343; P = .55). There was no difference in number of blood transfusions, length of stay, or complications., Conclusion: Intracapsular tranexamic acid is not inferior to intravenous tranexamic acid in decreasing blood loss and blood transfusion rate in primary total knee arthroplasty., (Copyright © 2016 Elsevier Inc. All rights reserved.)
- Published
- 2016
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10. Resminostat: Opening the door to epigenetic treatments for liver cancer.
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Zhao J and Lawless MW
- Subjects
- Humans, Disease Management, Epigenomics trends, Liver Diseases genetics, Liver Diseases therapy
- Published
- 2016
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11. Long noncoding RNAs in liver cancer: what we know in 2014.
- Author
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Zhao J, Greene CM, Gray SG, and Lawless MW
- Subjects
- Animals, Carcinoma, Hepatocellular pathology, Carcinoma, Hepatocellular therapy, Computer Simulation, Disease Progression, Epigenesis, Genetic, Humans, Liver Neoplasms pathology, Liver Neoplasms therapy, Survival Rate, Carcinoma, Hepatocellular genetics, Liver Neoplasms genetics, RNA, Long Noncoding genetics
- Abstract
Introduction: Hepatocellular carcinoma (HCC) is the most common form of primary liver cancer with an estimated over half a million new cases diagnosed annually. Due to the difficulty in early diagnosis and lack of effective treatment options, HCC is currently ranked as the second highest neoplastic-related mortality in the world, with an extremely low 5-year survival rate of between 6 and 11%. Long noncoding RNAs (lncRNAs), are genes lacking protein coding ability, have recently emerged as pivotal participants in biological processes, often dysregulated in a range of cancers, including HCC., Areas Covered: In this review, we highlight the recent findings of lncRNAs in HCC pathogenesis, with particular attention on epigenetic events. In silico analysis was utilized to emphasize intrinsic linkages within the ncRNA families associated with hepatocarcinogenesis., Expert Opinion: While our understanding of lncRNAs in the onset and progression of HCC is still in its infancy, there is no doubt that understanding the activities of ncRNAs will certainly secure strong biomarkers and improve treatment options for HCC patients.
- Published
- 2014
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12. Greater trochanteric hip pain.
- Author
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Kimpel DM, Garner CC, Magone KM, May JH, and Lawless MW
- Subjects
- Adult, Chronic Disease, Female, Humans, Middle Aged, Femur physiopathology, Hip physiopathology
- Abstract
In the patient with lateral hip pain, there is a broad differential diagnosis, making appropriate evaluation and management challenging. Greater trochanteric pain syndrome is a term used to denote chronic lateral hip pain and encompasses several painful soft tissue diagnoses including coxa saltans, trochanteric bursitis, and gluteus minimus and medius tendon tears. An overview of these common causes is presented through a series of cases that encompass the anatomic associations, classic presentations, diagnostic tests, and management strategies unique to each disorder. By reviewing this information, we hope to provide clinicians with the tools to evaluate greater trochanteric pain syndrome efficiently and effectively.
- Published
- 2014
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13. Stop feeding cancer: pro-inflammatory role of visceral adiposity in liver cancer.
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Zhao J and Lawless MW
- Subjects
- Humans, Interleukin-6 metabolism, Liver metabolism, Liver pathology, Models, Biological, Obesity metabolism, Tumor Necrosis Factor-alpha metabolism, Adiposity, Carcinoma, Hepatocellular metabolism, Intra-Abdominal Fat metabolism, Liver Neoplasms metabolism
- Abstract
Liver cancer is the fifth most common cancer in the world with an estimated over half a million new cases diagnosed every year. Due to the difficulty in early diagnosis and lack of treatment options, the prevalence of liver cancer continues to climb with a 5-year survival rate of between 6% and 11%. Coinciding with the rise of liver cancer, the prevalence of obesity has rapidly increased over the past two decades. Evidence from epidemiological studies demonstrates a higher risk of hepatocellular carcinoma (HCC) in obese individuals. Obesity is recognised as a low-grade inflammatory disease, this is of particular relevance as inflammation has been proposed as the seventh hallmark of cancer development with abdominal visceral adiposity considered as an important source of pro-inflammatory stimuli. Emerging evidence points towards the direct role of visceral adipose tissue rather than generalised body fat in carcinogenesis. Cytokines such as IL-6 and TNF-α secreted from visceral adipose tissue have been demonstrated to induce a chronic inflammatory condition predisposing the liver to a protumourigenic milieu. This review focuses on excess visceral adiposity rather than simple obesity; particularly adipokines and their implications for chronic inflammation, lipid accumulation, insulin resistance, Endoplasmic Reticulum (ER) stress and angiogenesis. Evidence of molecular signalling pathways that may give rise to the onset and progression of HCC in this context are depicted. Delineation of the pro-inflammatory role of visceral adiposity in liver cancer and its targeting will provide better rational and therapeutic approaches for HCC prevention and elimination. The concept of a central role for metabolism in cancer is the culmination of an effort that began with one of the 20th century's leading biochemists and Nobel laureate of 1931, Otto Warburg., (Copyright © 2013 Elsevier Ltd. All rights reserved.)
- Published
- 2013
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14. MicroRNAs and liver cancer associated with iron overload: therapeutic targets unravelled.
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Greene CM, Varley RB, and Lawless MW
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- Animals, Apoptosis, Carcinoma, Hepatocellular etiology, Carcinoma, Hepatocellular genetics, Carcinoma, Hepatocellular secondary, Carcinoma, Hepatocellular therapy, Disease Progression, Genetic Testing, Genetic Therapy, Humans, Iron Overload complications, Iron Overload genetics, Liver pathology, Liver Neoplasms etiology, Liver Neoplasms genetics, Liver Neoplasms pathology, Liver Neoplasms therapy, MicroRNAs therapeutic use, Neoplasm Invasiveness, Predictive Value of Tests, Carcinoma, Hepatocellular metabolism, Iron Overload metabolism, Liver metabolism, Liver Neoplasms metabolism, MicroRNAs metabolism
- Abstract
Primary liver cancer is a global disease that is on the increase. Hepatocellular carcinoma (HCC) accounts for most primary liver cancers and has a notably low survival rate, largely attributable to late diagnosis, resistance to treatment, tumour recurrence and metastasis. MicroRNAs (miRNAs/miRs) are regulatory RNAs that modulate protein synthesis. miRNAs are involved in several biological and pathological processes including the development and progression of HCC. Given the poor outcomes with current HCC treatments, miRNAs represent an important new target for therapeutic intervention. Several studies have demonstrated their role in HCC development and progression. While many risk factors underlie the development of HCC, one process commonly altered is iron homeostasis. Iron overload occurs in several liver diseases associated with the development of HCC including Hepatitis C infection and the importance of miRNAs in iron homeostasis and hepatic iron overload is well characterised. Aberrant miRNA expression in hepatic fibrosis and injury response have been reported, as have dysregulated miRNA expression patterns affecting cell cycle progression, evasion of apoptosis, invasion and metastasis. In 2009, miR-26a delivery was shown to prevent HCC progression, highlighting its therapeutic potential. Several studies have since investigated the clinical potential of other miRNAs with one drug, Miravirsen, currently in phase II clinical trials. miRNAs also have potential as biomarkers for the diagnosis of HCC and to evaluate treatment efficacy. Ongoing studies and clinical trials suggest miRNA-based treatments and diagnostic methods will have novel clinical applications for HCC in the coming years, yielding improved HCC survival rates and patient outcomes.
- Published
- 2013
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15. Semitendinosus muscle fatty infiltration following tendon harvest in rabbits.
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Vourazeris JD, Lawless MW, Markert RJ, Stills HF, and Boivin GP
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- Animals, Disease Models, Animal, Female, Postoperative Complications, Rabbits, Stifle pathology, Stifle surgery, Tendons surgery, Adipose Tissue pathology, Muscle, Skeletal pathology, Regeneration physiology, Tendons pathology, Tissue and Organ Harvesting adverse effects
- Abstract
The hamstring tendon autograft is one of the most commonly used graft choices in Anterior cruciate ligament (ACL) reconstruction. There are conflicting results regarding postoperative hamstring strength deficits in patients who have had a hamstring graft. The semitendinosus tendon has been shown to regenerate after harvesting for ACL autograft, suggesting that the muscle has the potential to regain normal function. However, no studies have been performed to define the microstructural changes that occur in the semitendinosus muscle after tendon resection. In this study, we hypothesized that fatty infiltration of the semitendinosus muscle after tendon harvest in New Zealand White rabbits increases postoperatively and remains constant or increases during the first year of repair. The semitendinosus tendon was unilaterally detached and harvested from 15 rabbits. Five rabbits were sacrificed at 3-, 6-, and 12-month intervals, and the semitendinosus muscle-tendon units were analyzed. The contralateral unoperated limb served as the control. The gross tendon and muscle dimensions and histologic percentage of fatty infiltration were measured. We found no significant difference in fatty infiltration at any time point between the control muscle and test specimens and that there was no progression of fatty infiltration over time. If these results hold true in humans, natural repair of the hamstring muscle following tendon harvest during ACL autograft reconstruction is not inhibited by fatty infiltration., (Copyright © 2013 Orthopaedic Research Society.)
- Published
- 2013
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16. Long noncoding RNAs and their role in the liver cancer axis.
- Author
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Zhao J and Lawless MW
- Published
- 2013
- Full Text
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17. Pegylated interferon-α induced hypoferremia is associated with the immediate response to treatment in hepatitis C.
- Author
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Ryan JD, Altamura S, Devitt E, Mullins S, Lawless MW, Muckenthaler MU, and Crowe J
- Subjects
- Adult, Aged, Antimicrobial Cationic Peptides genetics, Antiviral Agents therapeutic use, Carcinoma, Hepatocellular, Cell Line, Tumor, Cohort Studies, Drug Therapy, Combination, Female, Genotype, Hemochromatosis Protein, Hepcidins, Histocompatibility Antigens Class I genetics, Humans, Interferons, Interleukins genetics, Iron blood, Liver Neoplasms, Male, Membrane Proteins genetics, Middle Aged, Recombinant Proteins therapeutic use, STAT3 Transcription Factor metabolism, Viral Load drug effects, Antimicrobial Cationic Peptides blood, Drug Monitoring methods, Hepatitis C drug therapy, Interferon-alpha therapeutic use, Iron Deficiencies, Polyethylene Glycols therapeutic use, Ribavirin therapeutic use
- Abstract
Unlabelled: Pegylated interferon-α (PEG-IFN-α) forms an integral part of the current treatment for hepatitis C virus (HCV) infection. PEG-IFN-α suppresses HCV production by augmenting the innate antiviral immune response. Recent studies have reported the induction of hepcidin, the iron regulatory hormone, by IFN-α in vitro. As hepcidin plays an important role in innate immunity, we hypothesized that this finding may be of clinical relevance to HCV and investigated the changes in iron homeostasis during the first 24 hours of treatment. Blood samples were obtained from HCV patients immediately prior to and 6, 12, and 24 hours following the first dose of PEG-IFN-α/ribavirin (RBV). Samples were analyzed for hepcidin, cytokine, iron levels, and HCV viral load, and hepcidin messenger RNA (mRNA) expression was quantified in peripheral blood mononuclear cells. Hepcidin induction by IFN-α was further analyzed in cell culture. In HCV patients a single dose of PEG-IFN-α/RBV resulted in a significant increase in serum hepcidin, peaking at 12 hours, coinciding with a 50% reduction in serum iron and transferrin saturation over the 24-hour period. Patients with a ≥ 2 log decline in HCV viral load over the first 24 hours had significantly lower SI and TS levels at 12 and 24 hours. Moreover, 24-hour SI levels were an independent predictor of the immediate HCV viral decline, an indicator of ultimate treatment outcome. In cell culture, a direct induction of hepcidin by IFN-α was seen, controlled by the STAT3 transcription factor., Conclusion: Hepcidin induction occurs following the initiation of PEG-IFN-α treatment for HCV, and is mediated by way of STAT3 signaling. The subsequent hypoferremia was greatest in those with the most significant decline in viral load, identifying systemic iron withdrawal as a marker of immediate interferon-α efficacy in HCV patients., (Copyright © 2012 American Association for the Study of Liver Diseases.)
- Published
- 2012
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18. Toll-like receptor signalling in liver disease: ER stress the missing link?
- Author
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Lawless MW and Greene CM
- Subjects
- Animals, Humans, Models, Biological, Protein Transport, Endoplasmic Reticulum Stress immunology, Liver Diseases immunology, Signal Transduction immunology, Toll-Like Receptors metabolism
- Abstract
Toll-like receptors induce a complex inflammatory response that can function to alert the body to infection, neutralize pathogens and repair damaged tissues. Toll-like receptors are expressed on kupffer, endothelial, dendritic, biliary epithelial, hepatic stellate cells, and hepatocytes in the liver. The endoplasmic reticulum (ER) is a central organelle of eukaryotic cells that exists as a place of lipid synthesis, protein folding and protein maturation. The ER is a major signal transduction organelle that senses and responds to changes in homeostasis. Conditions interfering with the function of the ER are collectively known as ER stress and can be induced by accumulation of unfolded protein aggregates or by excessive protein traffic as can occur during viral infection. The ability of ER stress to induce an inflammatory response is considered to play a role in disease pathogenesis. Importantly, ER stress is viewed as a contributor to the pathogenesis of liver diseases with evidence linking components of ER homeostasis as requirements for optimal Toll-like receptor function. In this context this review discusses the association of Toll-like receptors with ER stress. This is an emerging paradigm in the understanding of Toll-like receptor signalling which may have an underlying role in the pathogenesis of liver disease., (Copyright © 2012 Elsevier Ltd. All rights reserved.)
- Published
- 2012
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19. Correlation between patella and patellar tendon width: An anatomic study.
- Author
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Dundon JM, Markert RJ, and Lawless MW
- Subjects
- Adult, Aged, Aged, 80 and over, Cadaver, Female, Humans, Male, Middle Aged, Patella anatomy & histology, Patellar Ligament anatomy & histology
- Abstract
Anterior cruciate ligament (ACL) rupture is a common injury among orthopaedic patients with many different treatment modalities including bone-patella-bone autograft (BPBA) ACL reconstruction. Patella tendon width has been reported to be a predictor of recovery speed and success following BPBA repair. This study reports on the strength of the relationship between patella width and patella tendon width. Twenty fresh frozen cadavers were included in the study. Patella and patellar tendon measurements were recorded at the midpoint of the patellar tendon. Pearson correlation and linear regression were used to determine the relationship between patella width and patellar tendon width. Bivariate correlations with 95% confidence intervals and coefficients of determination (R(2) ) are reported. The study used 20 cadavers, 12 men and 8 women with a mean age of 72 (standard deviation [SD] = 12; range = 44 to 87). The mean patella width was 49.24mm (SD = 4.11; range 42.33mm-56.33mm) while the mean patellar tendon width was 26.10mm (SD = 3.31; range 18.33mm-33.33mm). The correlation between patella width and patellar tendon width was 0.67 (95% confidence interval = 0.45 - 0.81). R(2), the percent of variance in patellar tendon width accounted for by patella width, was 0.45. The regression equation for predicting patellar tendon width (y) yielded a formula of y = 0.536 + -0.316 × patella width. A moderate correlation exists between patella width and patellar tendon width. Our data suggests that this correlation is strongest with wider patellas and is more loosely associated with smaller patellas., (Copyright © 2011 Wiley Periodicals, Inc.)
- Published
- 2012
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20. Hospital-acquired pneumonia after lung resection surgery is associated with characteristic cytokine gene expression.
- Author
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White M, Martin-Loeches I, Lawless MW, O'Dwyer MJ, Doherty DG, Young V, Kelleher D, McManus R, and Ryan T
- Subjects
- Aged, Algorithms, Biomarkers metabolism, Cross Infection metabolism, Cytokines metabolism, Disease Susceptibility, Female, Humans, Interferon-gamma genetics, Interferon-gamma metabolism, Interleukin-23 genetics, Interleukin-23 metabolism, Interleukin-6 genetics, Interleukin-6 metabolism, Male, Middle Aged, Pneumonia metabolism, Postoperative Complications metabolism, Prevalence, Prospective Studies, RNA, Messenger metabolism, Retrospective Studies, Tumor Necrosis Factor-alpha genetics, Tumor Necrosis Factor-alpha metabolism, Cross Infection epidemiology, Cytokines genetics, Gene Expression Regulation physiology, Lung physiopathology, Lung surgery, Pneumonia epidemiology, Postoperative Complications epidemiology
- Abstract
Background: Infection in humans has been linked with altered cytokine gene transcription. It is unclear whether this phenomenon is a consequence of an established disease process or precedes the infective process. The primary end point of this study was to determine whether hospital-acquired pneumonia (HAP) was associated with differential gene expression of interferon (IFN)-γ, tumor necrosis factor (TNF)-α, and IL-23p19. The secondary end point was to identify whether alteration in gene expression preceded the clinical onset of infection., Methods: Sixty consecutive patients undergoing elective thoracic surgery were recruited. HAP was diagnosed as per National Nosocomial Infection Surveillance guidelines. Messenger RNA (mRNA) and protein levels were analyzed preoperatively and 24 h and 5 days postoperatively., Results: Forty-one patients had an uncomplicated recovery. Nineteen patients developed HAP. IL-6, IL-10, IL-12p35, IL-23p19, IL-27p28, TNF-α, and IFN-γ mRNA and protein levels of IL-6, IL-23, and IFN-γ in peripheral blood leukocytes were analyzed before surgery and 24 h and 5 days postsurgery. IL-23p19 mRNA levels were reduced in the pneumonia group (median, 4.19; 10th-90th centile range, 3.90-4.71) compared with the nonpneumonia group (4.50; 3.85-5.32) day 1 postsurgery (P=02). IFN-γ mRNA levels were reduced in the pneumonia group (2.48; 1.20-3.20) compared with nonpneumonia group (2.81; 2.10-3.26) (P=03) day 5 postsurgery. Results are expressed as log to base 10 copy numbers of cytokine mRNA per 10 million β-actin mRNA copy numbers. All values are given as median and 10th to 90th centile range., Conclusions: Cytokine gene expression is altered immediately following surgery in patients with postoperative HAP.
- Published
- 2011
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21. Early proteomic analysis may allow noninvasive identification of hepatitis C response to treatment with pegylated interferon α-2b and ribavirin.
- Author
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Devitt EJ, Power KA, Lawless MW, Browne JA, Gaora PO, Gallagher WM, and Crowe J
- Subjects
- Adult, Antiviral Agents therapeutic use, Biomarkers blood, Drug Therapy, Combination, Female, Hepatitis C, Chronic metabolism, Humans, Interferon alpha-2, Male, Middle Aged, Prospective Studies, Recombinant Proteins, Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization, Drug Monitoring methods, Hepatitis C, Chronic drug therapy, Interferon-alpha therapeutic use, Polyethylene Glycols therapeutic use, Proteomics, Ribavirin therapeutic use
- Abstract
Background and Aim: Chronic hepatitis C virus (HCV) infection represents a significant disease burden worldwide. Approximately 170 million people are chronically infected. HCV can lead to liver fibrosis, cirrhosis and hepatocellular carcinoma. Current standard treatment with pegylated interferon and ribavirin is suboptimal and up to 60% of patients fail to respond. Week 4 and 12 HCV RNA is used as a marker of response with nonresponders at 12 weeks discontinuing treatment. Earlier identification of nonresponders using novel biomarkers would be beneficial in preventing unnecessary toxicities and cost. This study profiled the proteomic response to treatment in HCV patients within the first 24 h using surface-enhanced laser desorption-ionization time-of-flight mass spectrometry (SELDI-TOF MS)., Methods: Serum from 25 HCV infected individuals during the initial 24 h of treatment was profiled using SELDI-TOF MS. Arrays were analyzed on the ProteinChip Reader and time-of-flight spectra were generated. Peak detection was performed by Biomarker Wizard software and analyzed using BioConductor packages., Results: Significant differences were seen between the proteomic profiles of responders and nonresponders to treatment. Overall 70 peaks differentiated responders from nonresponders. A random forest classifier identified a panel of 20 peaks, which differentiated responders from nonresponders with 87.4% accuracy. The CM10 chip revealed 16 peaks identifying genotype 1 responders from nonresponders., Conclusion: This study identifies early proteomic spectra as potential predictors of HCV treatment response using SELDI-TOF MS. This illustrates the importance of early biomarkers in the prediction of response within the first 24 h, which may aid in tailoring HCV treatment regimens.
- Published
- 2011
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22. Targeting oxidative stress in cancer.
- Author
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Lawless MW, O'Byrne KJ, and Gray SG
- Subjects
- Acetylation drug effects, Animals, Anticarcinogenic Agents pharmacology, Anticarcinogenic Agents therapeutic use, Antineoplastic Agents therapeutic use, Carcinoma, Hepatocellular drug therapy, Carcinoma, Hepatocellular metabolism, Carcinoma, Non-Small-Cell Lung drug therapy, Carcinoma, Non-Small-Cell Lung metabolism, Epigenesis, Genetic drug effects, Histone Deacetylase Inhibitors therapeutic use, Histones metabolism, Humans, Liver Neoplasms drug therapy, Liver Neoplasms metabolism, Protein Processing, Post-Translational drug effects, Antineoplastic Agents pharmacology, Drug Design, Histone Acetyltransferases physiology, Histone Deacetylase Inhibitors pharmacology, Histone Deacetylases physiology, Oxidative Stress drug effects
- Abstract
Importance of the Field: Reactive oxygen species (ROS) occur as natural by-products of oxygen metabolism and have important cellular functions. Normally, the cell is able to maintain an adequate balance between the formation and removal of ROS either via anti-oxidants or through the use specific enzymatic pathways. However, if this balance is disturbed, oxidative stress may occur in the cell, a situation linked to the pathogenesis of many diseases, including cancer., Areas Covered in This Review: HDACs are important regulators of many oxidative stress pathways including those involved with both sensing and coordinating the cellular response to oxidative stress. In particular aberrant regulation of these pathways by histone deacetylases may play critical roles in cancer progression., What the Reader Will Gain: In this review we discuss the notion that targeting HDACs may be a useful therapeutic avenue in the treatment of oxidative stress in cancer, using chronic obstructive pulmonary disease (COPD), NSCLC and hepatocellular carcinoma (HCC) as examples to illustrate this possibility., Take Home Message: Epigenetic mechanisms may be an important new therapeutic avenue for targeting oxidative stress in cancer.
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- 2010
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23. Defective bone morphogenic protein signaling underlies hepcidin deficiency in HFE hereditary hemochromatosis.
- Author
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Ryan JD, Ryan E, Fabre A, Lawless MW, and Crowe J
- Subjects
- Adult, Hemochromatosis genetics, Hemochromatosis Protein, Hepcidins, Histocompatibility Antigens Class I genetics, Humans, Iron Overload genetics, Male, Membrane Proteins genetics, Middle Aged, Smad8 Protein genetics, Up-Regulation, Antimicrobial Cationic Peptides deficiency, Bone Morphogenetic Protein 6 physiology, Signal Transduction physiology, Smad6 Protein biosynthesis, Smad7 Protein biosynthesis
- Abstract
Unlabelled: Hereditary hemochromatosis (HH) is a common inherited iron overload disorder. The vast majority of patients carry the missense Cys282Tyr mutation of the HFE gene. Hepcidin, the central regulator of iron homeostasis, is deficient in HH, leading to unchecked iron absorption and subsequent iron overload. The bone morphogenic protein (BMP)/small mothers against decapentaplegic (Smad) signaling cascade is central to the regulation of hepcidin. Recent data from HH mice models indicate that this pathway may be defective in the absence of the HFE protein. Hepatic BMP/Smad signaling has not been characterized in a human HFE-HH cohort to date. Hepatic expression of BMP/Smad-related genes was examined in 20 HFE-HH males with significant iron overload, and compared to seven male HFE wild-type controls using quantitative real-time reverse transcription polymerase chain reaction. Hepatic expression of BMP6 was appropriately elevated in HFE-HH compared to controls (P = 0.02), likely related to iron overload. Despite this, no increased expression of the BMP target genes hepcidin and Id1 was observed, and diminished phosphorylation of Smad1/Smad5/Smad8 protein relative to iron burden was found upon immunohistochemical analysis, suggesting that impaired BMP signaling occurs in HFE-HH. Furthermore, Smad6 and Smad7, inhibitors of BMP signaling, were up-regulated in HFE-HH compared to controls (P = 0.001 and P = 0.018, respectively)., Conclusion: New data arising from this study suggest that impaired BMP signaling underlies the hepcidin deficiency of HFE-HH. Moreover, the inhibitory Smads, Smad6, and Smad7 are identified as potential disruptors of this signal and, hence, contributors to the pathogenesis of this disease.
- Published
- 2010
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24. Variant in CD209 promoter is associated with severity of liver disease in chronic hepatitis C virus infection.
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Ryan EJ, Dring M, Ryan CM, McNulty C, Stevenson NJ, Lawless MW, Crowe J, Nolan N, Hegarty JE, and O'Farrelly C
- Subjects
- Alleles, Drug Contamination, Female, Gene Frequency, Genetic Predisposition to Disease, Genotype, Hepacivirus genetics, Hepatitis C, Chronic virology, Humans, Linkage Disequilibrium, Liver Cirrhosis complications, Liver Cirrhosis genetics, Liver Cirrhosis pathology, Liver Diseases complications, Liver Diseases pathology, RNA, Viral genetics, Reverse Transcriptase Polymerase Chain Reaction, Rho(D) Immune Globulin immunology, Severity of Illness Index, Cell Adhesion Molecules genetics, Hepatitis C, Chronic complications, Lectins, C-Type genetics, Liver Diseases genetics, Polymorphism, Single Nucleotide, Promoter Regions, Genetic genetics, Receptors, Cell Surface genetics
- Abstract
CD209, a c-type lectin expressed by dendritic cells (DCs), acts as a pathogen recognition receptor. A single nucleotide polymorphism (SNP) in the promoter region of CD209 (-336 A/G; rs4804803) affects transcription and is associated with the severity of tuberculosis and dengue fever. Because CD209 binds hepatitis C virus (HCV) glycoprotein-E2, we investigated this SNP in the context of chronic HCV infection. A total of 131 Irish women who had received HCV-contaminated anti-D-immunoglobulin and 79 healthy control subjects were genotyped. We found no association between rs4804803 and the risk of HCV chronicity. However, of those with chronic infection, possession of at least one g-allele was associated with more advanced liver disease, with significantly higher liver fibrosis scores and levels of alanine transaminase (ALT) observed. We conclude that rs4804803, an SNP in the CD209 promoter, contributes to severity of liver disease in chronic HCV infection., (Copyright 2010 American Society for Histocompatibility and Immunogenetics. Published by Elsevier Inc. All rights reserved.)
- Published
- 2010
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25. Hemochromatosis protein HFE C282Y conformational considerations.
- Author
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Lawless MW
- Subjects
- Amino Acid Substitution, Cysteine genetics, Hemochromatosis genetics, Hemochromatosis Protein, Histocompatibility Antigens Class I chemistry, Humans, Membrane Proteins chemistry, Mutation, Protein Conformation, Protein Folding, Protein Transport, Tyrosine genetics, Hemochromatosis metabolism, Histocompatibility Antigens Class I genetics, Histocompatibility Antigens Class I metabolism, Membrane Proteins genetics, Membrane Proteins metabolism
- Published
- 2010
- Full Text
- View/download PDF
26. Transforming growth factor beta-1 and interleukin-17 gene transcription in peripheral blood mononuclear cells and the human response to infection.
- Author
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White M, Lawless MW, O'Dwyer MJ, Grealy R, Connell BO, Stordeur P, Kelleher D, McManus R, and Ryan T
- Subjects
- Adrenal Cortex Hormones therapeutic use, Aged, Aged, 80 and over, Bacteremia genetics, Bacteremia immunology, Case-Control Studies, Demography, Enzyme-Linked Immunosorbent Assay, Female, Gene Dosage genetics, Gene Expression Regulation, Humans, Male, RNA, Messenger genetics, RNA, Messenger metabolism, Sepsis drug therapy, Interleukin-17 blood, Interleukin-17 genetics, Leukocytes, Mononuclear metabolism, Sepsis genetics, Transcription, Genetic, Transforming Growth Factor beta1 blood, Transforming Growth Factor beta1 genetics
- Abstract
Introduction: The occurrence of severe sepsis may be associated with deficient pro-inflammatory cytokine production. Transforming growth factor beta-1 (TGFbeta-1) predominantly inhibits inflammation and may simultaneously promote IL-17 production. Interleukin-17 (IL-17) is a recently described pro-inflammatory cytokine, which may be important in auto-immunity and infection. We investigated the hypothesis that the onset of sepsis is related to differential TGFbeta-1 and IL-17 gene expression., Methods: A prospective observational study in a mixed intensive care unit (ICU) and hospital wards in a university hospital. Patients (59) with severe sepsis; 15 patients with gram-negative bacteraemia but without critical illness and 10 healthy controls were assayed for TGFbeta-1, IL-17a, IL-17f, IL-6 and IL-1beta mRNA in peripheral blood mononuclear cells (PBMC) by quantitative real-time PCR and serum protein levels by ELISA., Results: TGFbeta-1 mRNA levels are reduced in patients with bacteraemia and sepsis compared with controls (p=0.02). IL-6 mRNA levels were reduced in bacteraemic patients compared with septic patients and controls (p=0.008). IL-1beta mRNA levels were similar in all groups, IL-17a and IL-17f mRNA levels are not detectable in peripheral blood mononuclear cells. IL-6 protein levels were greater in patients with sepsis than bacteraemic and control patients (p<0.0001). Activated TGFbeta-1 and IL-17 protein levels were similar in all groups. IL-1beta protein was not detectable in the majority of patients., Conclusions: Down regulation of TGFbeta-1 gene transcription was related to the occurrence of infection but not the onset of sepsis. Interleukin-17 production in PBMC may not be significant in the human host response to infection., (Copyright 2010 Elsevier Ltd. All rights reserved.)
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- 2010
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27. Highly sensitivity adhesion molecules detection in hereditary haemochromatosis patients reveals altered expression.
- Author
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Norris S, White M, Mankan AK, and Lawless MW
- Subjects
- Adult, Aged, E-Selectin blood, Female, Flow Cytometry, Gene Frequency, Genotype, Hemochromatosis Protein, Humans, Intercellular Adhesion Molecule-1 blood, Iron metabolism, L-Selectin blood, Male, Middle Aged, Mutation, P-Selectin blood, Vascular Cell Adhesion Molecule-1 blood, Young Adult, Cell Adhesion Molecules blood, Hemochromatosis blood, Hemochromatosis genetics, Histocompatibility Antigens Class I genetics, Membrane Proteins genetics
- Abstract
Several abnormalities in the immune status of patients with hereditary haemochromatosis (HH) have been reported, suggesting an imbalance in their immune function. This may include persistent production of, or exposure to, altered immune signalling contributing to the pathogenesis of this disorder. Adhesion molecules L-, E- and P-Selectin, intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) are some of the major regulators of the immune processes and altered levels of these proteins have been found in pathological states including cardiovascular diseases, arthritis and liver cancer. The aim of this study was to assess L-, E- and P-Selectin, ICAM-1 and VCAM-1 expression in patients with HH and correlate these results with HFE mutation status and iron indexes. A total of 139 subjects were diagnosed with HH (C282Y homozygotes = 87, C282Y/H63D = 26 heterozygotes, H63D homozygotes = 26), 27 healthy control subjects with no HFE mutation (N/N), 18 normal subjects heterozygous for the H63D mutation served as age-sex-matched controls. We observed a significant decrease in L-selectin (P = 0.0002) and increased E-selectin and ICAM-1 (P = 0.0006 and P = 0.0059) expression in HH patients compared with healthy controls. This study observes for the first time that an altered adhesion molecules profile occurs in patients with HH that is associated with specific HFE genetic component for iron overload, suggesting that differential expression of adhesion molecules may play a role in the pathogenesis of HH.
- Published
- 2010
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28. Hemochromatosis: as a conformational disorder.
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Gray SG, Crowe J, and Lawless MW
- Subjects
- Animals, Endoplasmic Reticulum metabolism, Endoplasmic Reticulum pathology, Hemochromatosis therapy, Hemochromatosis Protein, Histocompatibility Antigens Class I metabolism, Humans, Membrane Proteins metabolism, Protein Conformation, Hemochromatosis metabolism, Hemochromatosis pathology, Histocompatibility Antigens Class I chemistry, Membrane Proteins chemistry
- Abstract
Hereditary hemochromatosis (HH) refers to a unique clinicopathologic subset of iron overload syndromes that includes the disorder related to C282Y homozygous mutation of the hemochromatosis protein (HFE), the most common form of hereditary hemochromatosis. Recent reports have highlighted analogies with the class of disorders, known as the conformational diseases whereby HFE C282Y mutant protein forms aggregates and is subsequently retained in the endoplasmic reticulum (ER). In conformational disorders, accumulation of unfolded or misfolded proteins in the ER can activate a complex cascade linked to the regulation of diverse physiologic processes, disease onset and progression. To-date, reviews on HFE C282Y HH have largely dealt with the end-stage consequence of this disorder (iron overload). However, our review focuses on upstream molecular events resulting from the mislocalization of the aggregation-prone HFE C282Y protein leading to potential advances in treatment and diagnosis.
- Published
- 2009
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29. Oxidative stress induced lung cancer and COPD: opportunities for epigenetic therapy.
- Author
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Lawless MW, O'Byrne KJ, and Gray SG
- Subjects
- Animals, Histone Deacetylase Inhibitors pharmacology, Humans, Lung Neoplasms pathology, Oxidative Stress drug effects, Pulmonary Disease, Chronic Obstructive pathology, Signal Transduction drug effects, Signal Transduction genetics, Epigenesis, Genetic drug effects, Lung Neoplasms genetics, Lung Neoplasms therapy, Oxidative Stress genetics, Pulmonary Disease, Chronic Obstructive genetics, Pulmonary Disease, Chronic Obstructive therapy
- Abstract
Reactive oxygen species (ROS) form as a natural by-product of the normal metabolism of oxygen and play important roles within the cell. Under normal circumstances the cell is able to maintain an adequate homeostasis between the formation of ROS and its removal through particular enzymatic pathways or via antioxidants. If however, this balance is disturbed a situation called oxidative stress occurs. Critically, oxidative stress plays important roles in the pathogenesis of many diseases, including cancer. Epigenetics is a process where gene expression is regulated by heritable mechanisms that do not cause any direct changes to the DNA sequence itself, and disruption of epigenetic mechanisms has important implications in disease. Evidence is emerging that histone deacetylases (HDACs) play decisive roles in regulating important cellular oxidative stress pathways including those involved with sensing oxidative stress and those involved with regulating the cellular response to oxidative stress. In particular aberrant regulation of these pathways by HDACs may play critical roles in cancer progression. In this review we discuss the current evidence linking epigenetics and oxidative stress and cancer, using chronic obstructive pulmonary disease and non-small cell lung cancer to illustrate the importance of epigenetics on these pathways within these disease settings.
- Published
- 2009
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30. Histone deacetylase inhibitors target diabetes via chromatin remodeling or as chemical chaperones?
- Author
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Lawless MW, O'Byrne KJ, and Gray SG
- Subjects
- Acetyltransferases metabolism, Chromatin Assembly and Disassembly, Drug Delivery Systems, Endoplasmic Reticulum metabolism, Enzyme Inhibitors therapeutic use, Gene Expression Regulation, Enzymologic, Humans, Hypoglycemic Agents therapeutic use, Molecular Chaperones pharmacology, Obesity complications, Obesity enzymology, Phenylbutyrates pharmacology, Diabetes Mellitus, Type 2 drug therapy, Diabetes Mellitus, Type 2 enzymology, Enzyme Inhibitors pharmacology, Histone Deacetylase Inhibitors, Histone Deacetylases metabolism, Hypoglycemic Agents pharmacology
- Abstract
Globally, obesity and diabetes (particularly type 2 diabetes) represents a major challenge to world health. Despite decades of intense research efforts, the genetic basis involved in diabetes pathogenesis & conditions associated with obesity are still poorly understood. Recent advances have led to exciting new developments implicating epigenetics as an important mechanism underpinning diabetes and obesity related disease. One epigenetic mechanism known as the "histone code" describes the idea that specific patterns of post-translational modifications to histones act like a molecular "code" recognised and used by non-histone proteins to regulate specific chromatin functions. One modification which has received significant attention is that of histone acetylation. The enzymes which regulate this modification are described as lysine acetyltransferases or KATs and histone deacetylases or HDACs. Due to their conserved catalytic domain HDACs have been actively targeted as a therapeutic target. Some of the known inhibitors of HDACs (HDACi) have also been shown to act as "chemical chaperones" to alleviate diabetic symptoms. In this review, we discuss the available evidence concerning the roles of HDACs in regulating chaperone function and how this may have implications in the management of diabetes.
- Published
- 2009
- Full Text
- View/download PDF
31. Targeting histone deacetylases for the treatment of disease.
- Author
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Lawless MW, Norris S, O'Byrne KJ, and Gray SG
- Subjects
- Acetylation, Animals, Anti-Inflammatory Agents, Non-Steroidal pharmacology, Anti-Inflammatory Agents, Non-Steroidal therapeutic use, Antineoplastic Agents pharmacology, Antineoplastic Agents therapeutic use, Diabetes Mellitus drug therapy, Endoplasmic Reticulum metabolism, Histone Acetyltransferases metabolism, Humans, Hypoglycemic Agents pharmacology, Hypoglycemic Agents therapeutic use, Neoplasms drug therapy, Protein Processing, Post-Translational, Diabetes Mellitus enzymology, Histone Deacetylase Inhibitors, Histone Deacetylases metabolism, Neoplasms enzymology
- Abstract
The 'histone code' is a well-established hypothesis describing the idea that specific patterns of post-translational modifications to histones act like a molecular 'code' recognized and used by non-histone proteins to regulate specific chromatin functions. One modification, which has received significant attention, is that of histone acetylation. The enzymes that regulate this modification are described as lysine acetyltransferases or KATs, and histone deacetylases or HDACs. Due to their conserved catalytic domain HDACs have been actively targeted as a therapeutic target. The pro-inflammatory environment is increasingly being recognized as a critical element for both degenerative diseases and cancer. The present review will discuss the current knowledge surrounding the clinical potential and current development of histone deacetylases for the treatment of diseases for which a pro-inflammatory environment plays important roles, and the molecular mechanisms by which such inhibitors may play important functions in modulating the pro-inflammatory environment.
- Published
- 2009
- Full Text
- View/download PDF
32. NF-kappaB regulation: the nuclear response.
- Author
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Mankan AK, Lawless MW, Gray SG, Kelleher D, and McManus R
- Subjects
- Animals, Humans, Molecular Chaperones metabolism, Protein Processing, Post-Translational, Cell Nucleus metabolism, NF-kappa B metabolism
- Abstract
Nuclear factor kappaB (NF-kappaB) is an inducible transcription factor that tightly regulates the expression of a large cohort of genes. As a key component of the cellular machinery NF-kappaB is involved in a wide range of biological processes including innate and adaptive immunity, inflammation, cellular stress responses, cell adhesion, apoptosis and proliferation. Appropriate regulation of NF-kappaB is critical for the proper function and survival of the cell. Aberrant NF-kappaB activity has now been implicated in the pathogenesis of several diseases ranging from inflammatory bowel disease to autoimmune conditions such as rheumatoid arthritis. Systems governing NF-kappaB activity are complex and there is an increased understanding of the importance of nuclear events in regulating NF-kappaB's activities as a transcription factor. A number of novel nuclear regulators of NF-kappaB such as IkappaB-zeta and PDZ and LIM domain 2 (PDLIM2) have now been identified, adding another layer to the mechanics of NF-kappaB regulation. Further insight into the functions of these molecules raises the prospect for better understanding and rational design of therapeutics for several important diseases.
- Published
- 2009
- Full Text
- View/download PDF
33. Targeting histone deacetylases for the treatment of immune, endocrine & metabolic disorders.
- Author
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Lawless MW, Norris S, O'Byrne KJ, and Gray SG
- Subjects
- Animals, Endoplasmic Reticulum metabolism, Humans, NF-kappa B physiology, Breast Neoplasms drug therapy, Diabetes Mellitus drug therapy, Enzyme Inhibitors therapeutic use, Histone Deacetylase Inhibitors, Lupus Erythematosus, Systemic drug therapy, Multiple Sclerosis drug therapy, Pancreatic Neoplasms drug therapy
- Abstract
The 'histone code' is a well-established hypothesis describing the idea that specific patterns of post-translational modifications to histones act like a molecular "code" recognised and used by non-histone proteins to regulate specific chromatin functions. One modification which has received significant attention is that of histone acetylation. The enzymes which regulate this modification are described as histone acetyltransferases or HATs, and histone deacetylases or HDACs [1]. Due to their conserved catalytic domain HDACs have been actively targeted as a therapeutic target. The pro-inflammatory environment is increasingly being recognised as a critical element for both degenerative diseases and cancer. The present review will discuss the current knowledge surrounding the clinical potential & current development of histone deacetylases for the treatment of diseases for which a proinflammatory environment plays important roles, and the molecular mechanisms by which such inhibitors may play important functions in modulating the proinflammatory environment.
- Published
- 2009
- Full Text
- View/download PDF
34. Characterization of tumour necrosis factor-alpha genetic variants and mRNA expression in patients with severe sepsis.
- Author
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O'Dwyer MJ, Mankan AK, Ryan AW, Lawless MW, Stordeur P, Kelleher D, McManus R, and Ryan T
- Subjects
- Adult, Aged, Aged, 80 and over, Alleles, Female, Gene Frequency, Haplotypes, Humans, Male, Middle Aged, Young Adult, Gene Expression Regulation, Genetic Variation, RNA, Messenger metabolism, Sepsis genetics, Sepsis metabolism, Tumor Necrosis Factor-alpha genetics, Tumor Necrosis Factor-alpha metabolism
- Abstract
Tumour necrosis factor-alpha (TNFalpha) has been implicated in the pathogenicity of severe sepsis by both genetic association studies and animal models. Conflicting functional data have emerged in relation to genetic variants and TNFalpha protein production. Therefore, we assessed the functionality of TNFalpha genetic variants in terms of mRNA production and their potential influence on outcome in the setting of severe sepsis. Sixty-two Irish Caucasian patients presenting with severe sepsis were recruited and TNFalpha mRNA and protein levels were quantified. Patient DNA was analysed for the presence of common promoter polymorphisms and haplotypes were inferred. An A allele at position -863 was associated with more TNFalpha mRNA on day 1 compared to C homozygotes (P = 0.037). There was a trend for G homozygotes at position -308 to produce more TNFalpha mRNA on day 1 than those carrying an A allele (P = 0.059). The presence of an A allele at -863 was associated with greater levels of TNFalpha mRNA in comparison with patients carrying the A allele at -308 on day 1 (P = 0.02). Patients homozygous for the A allele at position -308 had a higher mortality than those carrying the G allele (P = 0.01). Our data are consistent with recent reports suggesting that a deficient proinflammatory response may be harmful in human sepsis. This deficient inflammatory response may be mediated in part by polymorphisms in the TNFalpha promoter.
- Published
- 2008
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35. Mortality in humans with pneumonia and sepsis is related to an uncompensated anti-inflammatory response to infection.
- Author
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White M, Mankan A, Lawless MW, O'Dwyer MJ, McManus R, and Ryan T
- Subjects
- Animals, Bacteremia microbiology, Community-Acquired Infections microbiology, Community-Acquired Infections mortality, Disease Progression, Female, Humans, Inflammation diagnosis, Inflammation Mediators analysis, Interleukin-6 analysis, Male, Mice, Risk Assessment, Sensitivity and Specificity, Severity of Illness Index, Survival Analysis, Tumor Necrosis Factor-alpha analysis, Bacteremia mortality, Cause of Death, Cytokines analysis, Pneumonia microbiology, Pneumonia mortality
- Published
- 2008
- Full Text
- View/download PDF
36. Tauroursodeoxycholic acid: relieving the pathogenesis of HFE C282Y hereditary hemochromatosis.
- Author
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Lawless MW, Mankan AK, Ryan AW, and Norris S
- Subjects
- Cysteine, Endoplasmic Reticulum metabolism, Hemochromatosis metabolism, Hemochromatosis Protein, Homozygote, Humans, Mutation, Reactive Oxygen Species metabolism, Tyrosine, Antioxidants therapeutic use, Hemochromatosis drug therapy, Hemochromatosis genetics, Histocompatibility Antigens Class I genetics, Membrane Proteins genetics, Taurochenodeoxycholic Acid therapeutic use
- Published
- 2008
- Full Text
- View/download PDF
37. The human response to infection is associated with distinct patterns of interleukin 23 and interleukin 27 expression.
- Author
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O'Dwyer MJ, Mankan AK, White M, Lawless MW, Stordeur P, O'Connell B, Kelleher DP, McManus R, and Ryan T
- Subjects
- Adult, Aged, Aged, 80 and over, Bacteremia immunology, Case-Control Studies, Disease Progression, Female, Gene Expression Regulation, Humans, Interferon-gamma genetics, Interferon-gamma immunology, Interleukin-17 genetics, Interleukin-18 genetics, Interleukin-23 genetics, Male, Middle Aged, Prospective Studies, RNA, Messenger blood, Reverse Transcriptase Polymerase Chain Reaction, Survival Analysis, Interferon-gamma deficiency, Interleukin-17 blood, Interleukin-18 blood, Interleukin-23 blood, Systemic Inflammatory Response Syndrome immunology
- Abstract
Objective: The development and progression of severe sepsis is related to a deficiency in pro-inflammatory cytokine production, characterised by lesser IFNgamma levels, which are not explained by variations in levels of the main putative regulator of IFNgamma, namely IL-12. As alternative regulators of IFNgamma may be of greater importance in human sepsis, we investigated the hypothesis that the development of severe sepsis is related to variations in IL-18, IL-23 and IL-27 gene expression., Design and Setting: A prospective observational trial in a mixed intensive care unit (ICU) and hospital wards in a university teaching hospital., Patients and Participants: Sixty-two ICU patients with severe sepsis, 13 bacteraemic patients with no acute critical illness, and 10 healthy controls., Measurements and Results: All subjects were assayed for IL-18, IL-23 and IL-27 mRNA levels in peripheral blood. IL-27 mRNA levels distinguished between the three groups, with levels highest in the ICU group, intermediate in the bacteraemic group and lowest in the control group. IL-23 distinguished between the groups, with levels lowest in the ICU group. In late sepsis IL-23 and TNFalpha mRNA levels were directly related. IL-18 mRNA levels did not distinguish between the patient groups., Conclusions: We conclude that the deficient pro-inflammatory response in patients with sepsis is expansive and includes deficient IL-23 and excessive IL-27 gene expression. This provides further evidence that upregulation of a cytokine-based immune response is beneficial in sepsis.
- Published
- 2008
- Full Text
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38. Alpha-1 antitrypsin deficiency: a conformational disease associated with lung and liver manifestations.
- Author
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Greene CM, Miller SD, Carroll T, McLean C, O'Mahony M, Lawless MW, O'Neill SJ, Taggart CC, and McElvaney NG
- Subjects
- Animals, Autophagy physiology, Humans, Liver Diseases genetics, Liver Diseases therapy, Lung Diseases genetics, Lung Diseases therapy, Models, Biological, Protein Conformation, Protein Folding, alpha 1-Antitrypsin genetics, alpha 1-Antitrypsin Deficiency physiopathology, Liver Diseases etiology, Lung Diseases etiology, alpha 1-Antitrypsin chemistry, alpha 1-Antitrypsin Deficiency complications, alpha 1-Antitrypsin Deficiency genetics
- Abstract
Alpha-1 antitrypsin (A1AT) is a serine anti-protease produced chiefly by the liver. A1AT deficiency is a genetic disorder characterized by serum levels of less than 11 mumol/L and is associated with liver and lung manifestations. The liver disease, which occurs in up to 15% of A1AT-deficient individuals, is a result of toxic gain-of-function mutations in the A1AT gene, which cause the A1AT protein to fold aberrantly and accumulate in the endoplasmic reticulum of hepatocytes. The lung disease is associated with loss-of-function, specifically decreased anti-protease protection on the airway epithelial surface. The so-called 'Z' mutation in A1AT deficiency encodes a glutamic acid-to-lysine substitution at position 342 in A1AT and is the most common A1AT allele associated with disease. Here we review the current understanding of the molecular pathogenesis of A1AT deficiency and the best clinical management protocols.
- Published
- 2008
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39. Endoplasmic reticulum stress--a double edged sword for Z alpha-1 antitrypsin deficiency hepatoxicity.
- Author
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Lawless MW, Mankan AK, Gray SG, and Norris S
- Subjects
- Apoptosis physiology, Endoplasmic Reticulum pathology, Humans, Inflammation complications, Liver metabolism, Liver Diseases physiopathology, Models, Biological, NF-kappa B physiology, Phenotype, Protein Conformation, Protein Folding, Endoplasmic Reticulum physiology, Liver Diseases genetics, alpha 1-Antitrypsin Deficiency physiopathology
- Abstract
Several diverse disorders, including the liver disorder Z alpha-1 antitrypsin deficiency as well as cystic fibrosis, Alzheimer's, and Parkinson's disease arise from the same general disease mechanism and are now categorized under the term "conformational diseases", characterized by abnormal folding and subsequent aggregation of an underlying protein. In recent years, several important research advances in the cell biology of aggregation-prone mutant proteins and pathobiological mechanisms of liver disease in general have proven paramount to our understanding of Z alpha-1 antitrypsin deficiency. This liver disease underlines the principle mechanisms of conformational disorders contained within the four pillars of endoplasmic reticulum stress: (1) protein degradation, (2) endoplasmic overload response, (3) unfolded protein response and (4) cellular death pathway. This four-stage model of Z alpha-1 antitrypsin hepatoxicity is elegant in its simplicity and helps explain the clinical manifestations of this condition. Endoplasmic reticulum stress responses have evolved to be protective, however when they are ineffective, toxic damage occurs demonstrating how these responses can be described as a double edged sword. In this context, one of the most perplexing problems in modern biology is to understand how the cell "chooses" between adaptation and demise in response to stress. When one pathway becomes predominant, a delicate balance is perturbed and either an adaptive or a lethal response ensues. Understanding how the endoplasmic reticulum stress signals potentially play a role in directing a clinical outcome may lead to better prospects of more rational approaches to investigation and therapy for this liver disease.
- Published
- 2008
- Full Text
- View/download PDF
40. Hereditary hemochromatosis should be considered a conformational disorder.
- Author
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Lawless MW, Mankan AK, and Norris S
- Subjects
- Alleles, Cysteine chemistry, Disulfides chemistry, Genetic Diseases, Inborn genetics, Hemochromatosis Protein, Histocompatibility Antigens Class I chemistry, Homozygote, Humans, Membrane Proteins chemistry, Models, Genetic, Models, Theoretical, Protein Conformation, Protein Folding, Risk, Hemochromatosis diagnosis, Hemochromatosis genetics, Histocompatibility Antigens Class I genetics, Membrane Proteins genetics, Mutation
- Abstract
Hereditary hemochromatosis (HH) is a genetic disease associated with iron overload, in which individuals homozygous for the mutant C282Y HFE associated allele are at risk of developing liver disease, diabetes and arthritis. Conformational diseases are a class of disorders associated with the expression of misfolded protein and examples include conditions such as Alzheimer's, Parkinson's, Z alpha 1-antitrypsin deficiency and Huntington's diseases. HFE C282Y is a mutant protein that does not fold correctly forming aggregates and is retained in the Endoplasmic Reticulum (ER). Consequently, we propose that HH associated with the C282Y HFE mutation should be considered a conformational disorder.
- Published
- 2008
- Full Text
- View/download PDF
41. Elevated MCP-1 serum levels are associated with the H63D mutation and not the C282Y mutation in hereditary hemochromatosis.
- Author
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Lawless MW, White M, Mankan AK, O'Dwyer MJ, and Norris S
- Subjects
- Adult, Aged, Female, Ferritins blood, Hemochromatosis Protein, Heterozygote, Homozygote, Humans, Iron blood, Male, Middle Aged, Mutation, Transferrin analysis, Chemokine CCL2 blood, Hemochromatosis blood, Hemochromatosis genetics, Histocompatibility Antigens Class I genetics, Membrane Proteins genetics
- Abstract
Monocyte chemoattractant protein-1 (MCP-1) is a major lymphocyte and inflammatory chemokine associated with persistent inflammatory states. Several abnormalities in the immune status of patients with hereditary hemochromatosis (HH) have been reported, suggesting an imbalance in their immune function. This may include persistent production of, or exposure to, inflammatory cytokines contributing to the pathogenesis of this disorder. The aim of this study was to assess MCP-1 levels in patients with HH and correlate these results with HFE status and iron indexes. One hundred and thirty-nine subjects diagnosed with HH (C282Y homozygotes = 87, C282Y/H63D = 26 heterozygotes, H63D homozygotes = 26), 27 healthy control subjects with no HFE mutation (N/N), and 18 normal subjects heterozygous for the H63D mutation served as age- and sex-matched controls. Ferritin and transferrin saturation and the presence of HFE mutation status were correlated with MCP-1 levels. Full white blood cell count analysis was also performed. We found a strongly significant decrease in MCP-1 protein levels in the C282Y homozygotes compared with the H63D homozygotes (P = 0.0009) and C282Y/H63D heterozygotes (P = 0.002). Similarly, MCP-1 protein levels in the C282Y homozygotes were decreased compared with the healthy controls (P = 0.00076). Furthermore, MCP-1 serum levels were elevated in H63D patients compared with the healthy controls (P = 0.0008). This study suggests for the first time that a differential expression of MCP-1 protein in patients with HH is associated with the specific HFE genetic component for iron overload. Therefore, these findings offer a possible explanation in the variable clinical spectrum of pathogenesis in patients with HH through abnormalities of an imbalance in the immune states of patients with HH.
- Published
- 2007
- Full Text
- View/download PDF
42. Tauroursodeoxycholic acid inhibits apoptosis induced by Z alpha-1 antitrypsin via inhibition of Bad.
- Author
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Miller SD, Greene CM, McLean C, Lawless MW, Taggart CC, O'Neill SJ, and McElvaney NG
- Subjects
- Caspase 3 metabolism, Caspases, Initiator physiology, Cells, Cultured, Cytochromes c metabolism, Humans, Phosphatidylinositol 3-Kinases physiology, Phosphorylation, bcl-Associated Death Protein metabolism, Apoptosis drug effects, Taurochenodeoxycholic Acid pharmacology, alpha 1-Antitrypsin physiology, bcl-Associated Death Protein antagonists & inhibitors
- Abstract
Unlabelled: Z alpha-1 antitrypsin (AAT) deficiency is a genetic disease associated with accumulation of misfolded AAT in the endoplasmic reticulum (ER) of hepatocytes. ZAAT-expressing cells display ER stress responses including nuclear factor kappaB activation and apoptosis. Using an in vitro model of ZAAT ER accumulation, we investigated the mechanism of ZAAT-mediated ER-induced apoptosis and evaluated methods to inhibit this process. Here we demonstrate that expression of ZAAT, but not normal MAAT, in HEK293 cells leads to cleavage and activation of caspase-4 and induces apoptosis that is characterized by activation of caspase-3 and caspase-7 and DNA fragmentation. Similar effects are also induced using the ER agonist thapsigargin. A caspase-4-specific short interfering RNA (siRNA) does not impair ZAAT-induced caspase-3/7 activation or cell death in these cells. However, inhibition studies performed using tauroursodeoxycholic acid (TUDCA) demonstrate its ability to inhibit caspase-4 and caspase-3/7 activation, mitochondrial cytochrome c release, and caspase-3 cleavage induced by ZAAT and to promote cell survival. The mechanism by which TUDCA (tauroursodeoxycholic acid) promotes cell survival in ZAAT-expressing cells involves phosphorylation and inactivation of the proapoptotic factor Bad. TUDCA is unable to rescue cells from apoptosis or phosphorylate Bad in the presence of LY294002, a selective P-I-3-kinase inhibitor., Conclusion: These data show that caspase-4 is not essential for ZAAT-induced apoptosis in HEK293 cells and implicates P-I-3-kinase and Bad as potential therapeutic targets for the liver disease associated with ZAAT deficiency.
- Published
- 2007
- Full Text
- View/download PDF
43. Expression of hereditary hemochromatosis C282Y HFE protein in HEK293 cells activates specific endoplasmic reticulum stress responses.
- Author
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Lawless MW, Mankan AK, White M, O'Dwyer MJ, and Norris S
- Subjects
- Activating Transcription Factor 6 metabolism, Apoptosis drug effects, Apoptosis genetics, Cells, Cultured, Chemokine CCL2 metabolism, Endoplasmic Reticulum Chaperone BiP, Gene Expression Regulation, Hemochromatosis Protein, Humans, Interleukin-8 metabolism, Models, Biological, Protein Transport, Signal Transduction, Taurochenodeoxycholic Acid pharmacology, Transcription Factor CHOP metabolism, Transfection, alpha 1-Antitrypsin genetics, Endoplasmic Reticulum metabolism, Histocompatibility Antigens Class I genetics, Membrane Proteins genetics, Polymorphism, Single Nucleotide, Protein Folding
- Abstract
Background: Hereditary Hemochromatosis (HH) is a genetic disease associated with iron overload, in which individuals homozygous for the mutant C282Y HFE associated allele are at risk for the development of a range of disorders particularly liver disease. Conformational diseases are a class of disorders associated with the expression of misfolded protein. HFE C282Y is a mutant protein that does not fold correctly and consequently is retained in the Endoplasmic Reticulum (ER). In this context, we sought to identify ER stress signals associated with mutant C282Y HFE protein expression, which may have a role in the molecular pathogenesis of HH., Results: Vector constructs of Wild type HFE and Mutant C282Y HFE were made and transfected into HEK293 cell lines. We have shown that expression of C282Y HFE protein triggers both an unfolded protein response (UPR), as revealed by the increased GRP78, ATF6 and CHOP expression, and an ER overload response (EOR), as indicated by NF-kappaB activation. Furthermore, C282Y HFE protein induced apoptotic responses associated with activation of ER stress. Inhibition studies demonstrated that tauroursodeoxycholic acid, an endogenous bile acid, downregulates these events. Finally, we found that the co-existence of both C282Y HFE and Z alpha 1-antitrypsin protein (the protein associated with the liver disease of Z alpha 1-antitrypsin deficiency) expression on ER stress responses acted as potential disease modifiers with respect to each other., Conclusion: Our novel observations suggest that both the ER overload response (EOR) and the unfolded protein response (UPR) are activated by mutant C282Y HFE protein.
- Published
- 2007
- Full Text
- View/download PDF
44. Activation of endoplasmic reticulum-specific stress responses associated with the conformational disease Z alpha 1-antitrypsin deficiency.
- Author
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Lawless MW, Greene CM, Mulgrew A, Taggart CC, O'Neill SJ, and McElvaney NG
- Subjects
- Animals, CHO Cells, Carrier Proteins physiology, Cell Line, Cricetinae, Endoplasmic Reticulum genetics, Endoplasmic Reticulum Chaperone BiP, Eukaryotic Initiation Factor-2 metabolism, Humans, Interleukin-6 biosynthesis, Interleukin-8 biosynthesis, Molecular Chaperones physiology, Mutagenesis, Site-Directed, NF-kappa B metabolism, Phosphorylation, Protein Conformation, Protein Subunits metabolism, Signal Transduction genetics, Transfection, alpha 1-Antitrypsin biosynthesis, alpha 1-Antitrypsin physiology, alpha 1-Antitrypsin Deficiency metabolism, Endoplasmic Reticulum enzymology, Endoplasmic Reticulum metabolism, Heat-Shock Proteins, Protein Folding, alpha 1-Antitrypsin chemistry, alpha 1-Antitrypsin genetics, alpha 1-Antitrypsin Deficiency enzymology, alpha 1-Antitrypsin Deficiency genetics
- Abstract
Conformational diseases are a class of disorders associated with aberrant protein accumulation in tissues and cellular compartments. Z alpha1-antitrypsin (A1AT) deficiency is a genetic disease associated with accumulation of misfolded A1AT in the endoplasmic reticulum (ER) of hepatocytes. We sought to identify intracellular events involved in the molecular pathogenesis of Z A1AT-induced liver disease using an in vitro model system of Z A1AT ER accumulation. We investigated ER stress signals induced by Z A1AT and demonstrated that both the ER overload response and the unfolded protein response were activated by mutant Z A1AT, but not wild-type M A1AT. Interestingly, activation of the unfolded protein response pathway required an additional insult, whereas NF-kappa B activation, a hallmark of the ER overload response, was constitutive. These findings have important implications for the design of future therapeutics for Z A1AT liver disease and may also impact on drug design for other conformational diseases.
- Published
- 2004
- Full Text
- View/download PDF
45. Foot pressures during gait: a comparison of techniques for reducing pressure points.
- Author
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Lawless MW, Reveal GT, and Laughlin RT
- Subjects
- Adult, Female, Humans, Male, Monitoring, Physiologic, Orthopedic Equipment, Pressure, Foot physiology, Gait physiology
- Abstract
Purpose: Various methods have been used to redistribute plantar surface foot pressure in patients with foot ulcers. This study was conducted to determine the effectiveness of four modalities (fracture walker, fracture walker with insert, and open and closed toe total contact casts) in reducing plantar foot pressure., Methods: Ten healthy, normal volunteer subjects had an F-scan sensor (ultra thin shoe insert pressure monitor) placed under the right foot. They then ambulated on a flat surface, maintaining their normal gait. Dynamic plantar pressures were averaged over 10 steps at four different sites (plantar surface of great toe, first metatarsal head, base of fifth metatarsal, and plantar heel). All subjects repeated this sequence under five different testing conditions (barefoot, with a fracture walker, fracture walker with arch support insert, open and closed toe total contact cast). Each subject's barefoot pressures were then compared with the pressures during the different modalities., Results: All four treatment modalities significantly reduced (p < 0.05) plantar pressure at the first metatarsal head (no method was superior). The fracture walker, fracture walker with insert, and open toe total contact cast significantly reduced pressure at the heel. Pressures at the base of the fifth metatarsal and great toe were not significantly reduced with any treatment form., Conclusion: The fracture walker, with and without arch support, and total contact cast can effectively reduce plantar pressure at the heel and first metatarsal head.
- Published
- 2001
- Full Text
- View/download PDF
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