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Schönborn M, Łączak P, Pasieka P, Borys S, Płotek A, Maga P. Pro- and Anti-Angiogenic Factors: Their Relevance in Diabetic Foot Syndrome-A Review. Angiology 2021; 73:299-311. [PMID: 34541892 DOI: 10.1177/00033197211042684] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Peripheral arterial disease can involve tissue loss in up to 50% of patients with diabetic foot syndrome (DFS). Consequently, revascularization of narrowed or occluded arteries is one of the most common forms of comprehensive treatment. However, technically successful angioplasty does not always result in the healing of ulcers. The pathomechanism of this phenomenon is still not fully understood, but inadequate angiogenesis in tissue repair may play an essential role. Changes in pro- and anti-angiogenic factors among patients with DFS are not always clear and conclusive. In particular, some studies underline the role of decreased concentration of pro-angiogenic factors and higher levels of anti-angiogenic mediators. Nevertheless, there are still controversial issues, including the paradox of impaired wound healing despite high concentrations of some pro-angiogenic factors, dynamics of their expression during the healing process, and their mutual relationships. Exploring this process among diabetic patients may provide new insight into well-known methods of treatment and show their real benefits and chances for improving outcomes.
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Affiliation(s)
- Martyna Schönborn
- Department of Angiology, Faculty of Medicine, 162261Jagiellonian University Medical College, Krakow, Poland.,Doctoral School of Medical and Health Sciences, 162261Jagiellonian University, Krakow, Poland
| | - Patrycja Łączak
- Department of Angiology, Faculty of Medicine, 162261Jagiellonian University Medical College, Krakow, Poland
| | - Paweł Pasieka
- Department of Angiology, Faculty of Medicine, 162261Jagiellonian University Medical College, Krakow, Poland
| | - Sebastian Borys
- Department of Metabolic Diseases, Faculty of Medicine, 162261Jagiellonian University Medical College, Krakow, Poland
| | - Anna Płotek
- Department of Angiology, Faculty of Medicine, 162261Jagiellonian University Medical College, Krakow, Poland
| | - Paweł Maga
- Department of Angiology, Faculty of Medicine, 162261Jagiellonian University Medical College, Krakow, Poland
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D’Ippolito S, Di Nicuolo F, Papi M, Castellani R, Palmieri V, Masciullo V, Arena V, Tersigni C, Bernabei M, Pontecorvi A, Scambia G, Di Simone N. Expression of Pinopodes in the Endometrium from Recurrent Pregnancy Loss Women. Role of Thrombomodulin and Ezrin. J Clin Med 2020; 9:E2634. [PMID: 32823767 PMCID: PMC7464296 DOI: 10.3390/jcm9082634] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 08/04/2020] [Accepted: 08/09/2020] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Pinopode expression has been suggested as a marker of endometrial receptivity. METHODS We set up an experimental study comparing endometrial tissue from recurrent pregnancy loss (RPL, n = 30) and fertile control (CTR, n = 20) women in terms of pinopode expression/morphology; expression of thrombomodulin (TM) and ezrin; cytoskeletal organization. Endometrial samples were collected during implantation window and evaluated by scanning electron microscopy, western blot, and immunofluorescence. RESULTS We found that RPL endometrial tissue showed: (i) increased pinopodes density (* p < 0.05); (ii) a reduced diameter of pinopodes (* p < 0.05); (iii) a decreased TM and ezrin expression (p < 0.05). Additionally, confocal images showed a significantly reduced expression of phosphorylated (p)-ezrin, confirming the results obtained through immunoblot analysis. Immunofluorescence staining showed that in CTR samples, junctions between cells are intact and clearly visible, whereas actin filaments appear completely lost in RPL endometrial samples; this suggests that, due to the impaired expression and activity of TM and ezrin, actin does not bind to plasma membrane in order to orchestrate the cytoskeletal actin filaments. CONCLUSIONS Our findings suggest that an impaired expression of TM and expression/activation of ezrin may affect the connection between the TM and actin cytoskeleton, impairing the organization of cytoskeleton and, eventually, the adequate pinopode development.
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Affiliation(s)
- Silvia D’Ippolito
- Dipartimento di Scienze della Salute della Donna, del Bambino e di Sanità Pubblica, Fondazione Policlinico Universitario A. Gemelli, Istituto di Ricovero e Cura a Carattere Scientifico (I.R.C.C.S.), 00168 Roma, Italy; (V.M.); (V.A.); (C.T.); (G.S.)
| | - Fiorella Di Nicuolo
- Paolo VI International Scientific Institute, Università Cattolica del Sacro Cuore, 00168 Roma, Italy; (F.D.N.); (A.P.)
| | - Massimiliano Papi
- Dipartimento di Neuroscienze, Università Cattolica del Sacro Cuore, Fondazione Policlinico Universitario A. Gemelli Istituto di Ricovero e Cura a Carattere Scientifico (I.R.C.C.S.), 00168 Roma, Italy; (M.P.); (V.P.)
| | - Roberta Castellani
- Dipartimento di Scienze della Vita e Sanità Pubblica, Università Cattolica del Sacro Cuore, 00168 Roma, Italy;
| | - Valentina Palmieri
- Dipartimento di Neuroscienze, Università Cattolica del Sacro Cuore, Fondazione Policlinico Universitario A. Gemelli Istituto di Ricovero e Cura a Carattere Scientifico (I.R.C.C.S.), 00168 Roma, Italy; (M.P.); (V.P.)
| | - Valeria Masciullo
- Dipartimento di Scienze della Salute della Donna, del Bambino e di Sanità Pubblica, Fondazione Policlinico Universitario A. Gemelli, Istituto di Ricovero e Cura a Carattere Scientifico (I.R.C.C.S.), 00168 Roma, Italy; (V.M.); (V.A.); (C.T.); (G.S.)
| | - Vincenzo Arena
- Dipartimento di Scienze della Salute della Donna, del Bambino e di Sanità Pubblica, Fondazione Policlinico Universitario A. Gemelli, Istituto di Ricovero e Cura a Carattere Scientifico (I.R.C.C.S.), 00168 Roma, Italy; (V.M.); (V.A.); (C.T.); (G.S.)
| | - Chiara Tersigni
- Dipartimento di Scienze della Salute della Donna, del Bambino e di Sanità Pubblica, Fondazione Policlinico Universitario A. Gemelli, Istituto di Ricovero e Cura a Carattere Scientifico (I.R.C.C.S.), 00168 Roma, Italy; (V.M.); (V.A.); (C.T.); (G.S.)
| | - Micaela Bernabei
- Istituto di Anatomia e Istologia Patologica, Università Cattolica del Sacro Cuore, 00168 Roma, Italy;
| | - Alfredo Pontecorvi
- Paolo VI International Scientific Institute, Università Cattolica del Sacro Cuore, 00168 Roma, Italy; (F.D.N.); (A.P.)
- Dipartimento di Scienze Gastroenterologiche, Endocrino-Metaboliche e Nefro-Urologiche, Fondazione Policlinico Universitario A. Gemelli, Istituto di Ricovero e Cura a Carattere Scientifico (I.R.C.C.S.), 00168 Roma, Italy
- Istituto di Patologia Medica, Università Cattolica del Sacro Cuore, 00168 Roma, Italy
| | - Giovanni Scambia
- Dipartimento di Scienze della Salute della Donna, del Bambino e di Sanità Pubblica, Fondazione Policlinico Universitario A. Gemelli, Istituto di Ricovero e Cura a Carattere Scientifico (I.R.C.C.S.), 00168 Roma, Italy; (V.M.); (V.A.); (C.T.); (G.S.)
- Dipartimento di Scienze della Vita e Sanità Pubblica, Università Cattolica del Sacro Cuore, 00168 Roma, Italy;
| | - Nicoletta Di Simone
- Dipartimento di Scienze della Salute della Donna, del Bambino e di Sanità Pubblica, Fondazione Policlinico Universitario A. Gemelli, Istituto di Ricovero e Cura a Carattere Scientifico (I.R.C.C.S.), 00168 Roma, Italy; (V.M.); (V.A.); (C.T.); (G.S.)
- Dipartimento di Scienze della Vita e Sanità Pubblica, Università Cattolica del Sacro Cuore, 00168 Roma, Italy;
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Lang TC, Zhao R, Kim A, Wijewardena A, Vandervord J, Xue M, Jackson CJ. A Critical Update of the Assessment and Acute Management of Patients with Severe Burns. Adv Wound Care (New Rochelle) 2019; 8:607-633. [PMID: 31827977 PMCID: PMC6904939 DOI: 10.1089/wound.2019.0963] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Accepted: 04/18/2019] [Indexed: 12/14/2022] Open
Abstract
Significance: Burns are debilitating, life threatening, and difficult to assess and manage. Recent advances in assessment and management have occurred since a comprehensive review of the care of patients with severe burns was last published, which may influence research and clinical practice. Recent Advances: Recent advances have occurred in the understanding of burn pathophysiology, which has led to the identification of potential biomarkers of burn severity, such as protein C. There is new evidence about the potential superiority of natural colloids over crystalloids during fluid resuscitation, and new evidence about components of initial and perioperative management, including an improved understanding of pain following burns. Critical Issues: The limitations of the clinical examination highlight the need for imaging and biomarkers to assist in estimations of burn severity. Fluid resuscitation reduces mortality, although there is conjecture over the ideal method. The subsequent perioperative period is associated with significant morbidity and the evidence for preventing and treating pain, infection, and fluid overload while maximizing wound healing potential is described. Future Directions: Promising developments are ongoing in imaging technology, histopathology, biomarkers, and wound healing adjuncts such as hyperbaric oxygen therapy, topical negative pressure therapy, stem cell treatments, and skin substitutes. The greatest benefit from further research on management of patients with burns would most likely be derived from the elucidation of optimal fluid resuscitation protocols, pain management protocols, and surgical techniques from randomized controlled trials.
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Affiliation(s)
- Thomas Charles Lang
- Department of Anesthesia, Prince of Wales and Sydney Children's Hospitals, Randwick, Australia
| | - Ruilong Zhao
- Sutton Laboratories, The Kolling Institute, St. Leonards, Australia
| | - Albert Kim
- Department of Critical Care Medicine, Royal North Shore Hospital, St. Leonards, Australia
| | - Aruna Wijewardena
- Department of Burns, Reconstructive and Plastic Surgery, Royal North Shore Hospital, St. Leonards, Australia
| | - John Vandervord
- Department of Burns, Reconstructive and Plastic Surgery, Royal North Shore Hospital, St. Leonards, Australia
| | - Meilang Xue
- Sutton Laboratories, The Kolling Institute, St. Leonards, Australia
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Lang TC, Zhao R, Kim A, Wijewardena A, Vandervord J, McGrath R, Fitzpatrick S, Fulcher G, Jackson CJ. Plasma protein C levels are directly associated with better outcomes in patients with severe burns. Burns 2019; 45:1659-1672. [PMID: 31221425 DOI: 10.1016/j.burns.2019.05.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Revised: 03/20/2019] [Accepted: 05/01/2019] [Indexed: 11/30/2022]
Abstract
Protein C circulates in human plasma to regulate inflammation and coagulation. It has shown a crucial role in wound healing in animals, and low plasma levels predict the presence of a wound in diabetic patients. However, no detailed study has measured protein C levels in patients with severe burns over the course of a hospital admission. A severe burn is associated with dysfunction of inflammation and coagulation as well as a significant risk of morbidity and mortality. The current methods of burn assessment have shortcomings in reliability and have limited prognostic value. The discovery of a biomarker that estimates burn severity and predicts clinical events with greater accuracy than current methods may improve management, resource allocation and patient counseling. This is the first study to assess the potential role of protein C as a biomarker of burn severity. We measured the plasma protein C levels of 86 patients immediately following a severe burn, then every three days over the first three weeks of a hospital admission. We also analysed the relationships between burn characteristics, blood test results including plasma protein C levels and clinical events. We used a primary composite outcome of increased support utilisation defined as: a mean intravenous fluid administration volume of five litres or more per day over the first 72 h of admission, a length of stay in the intensive care unit of more than four days, or greater than four surgical procedures during admission. The hypothesis was that low protein C levels would be negatively associated with increased support utilisation. At presentation to hospital after a severe burn, the mean plasma protein C level was 76 ± 20% with a range of 34-130% compared to the normal range of 70-180%. The initial low can be plausibly explained by impaired synthesis, increased degradation and excessive consumption of protein C following a burn. Levels increased gradually over six days then remained at a steady-state until the end of the inpatient study period, day 21. A multivariable regression model (Nagelkerke's R2 = 0.83) showed that the plasma protein C level on admission contributed the most to the ability of the model to predict increased support utilisation (OR = 0.825 (95% CI = 0.698-0.977), P = 0.025), followed by burn size (OR = 1.252 (95% CI = 1.025-1.530), P = 0.027), burn depth (partial thickness was used as the reference, full thickness OR = 80.499 (1.569-4129.248), P = 0.029), and neutrophil count on admission (OR = 1.532 (95% CI = 0.950-2.473), P = 0.08). Together, these four variables predicted increased support utilisation with 93.2% accuracy, 83.3% sensitivity and 97.6% specificity. However if protein C values were disregarded, only 49.5% of the variance was explained, with 82% accuracy, 63% sensitivity and 91.5% specificity. Thus, protein C may be a useful biomarker of burn severity and study replication will enable validation of these novel findings.
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Affiliation(s)
- Thomas Charles Lang
- Sutton Laboratories Level 10, The Kolling Institute, The University of Sydney, Northern Clinical School, Royal North Shore Hospital, Reserve Rd, St. Leonards, 2065, NSW, Australia; Department of Anaesthesia, Prince of Wales and Sydney Children's Hospitals, Barker St, Randwick, 2031, NSW, Australia.
| | - Ruilong Zhao
- Sutton Laboratories Level 10, The Kolling Institute, The University of Sydney, Northern Clinical School, Royal North Shore Hospital, Reserve Rd, St. Leonards, 2065, NSW, Australia
| | - Albert Kim
- Royal North Shore Hospital, Reserve Rd St., Leonards, 2065, NSW, Australia
| | - Aruna Wijewardena
- Royal North Shore Hospital, Reserve Rd St., Leonards, 2065, NSW, Australia
| | - John Vandervord
- Royal North Shore Hospital, Reserve Rd St., Leonards, 2065, NSW, Australia
| | - Rachel McGrath
- Royal North Shore Hospital, Reserve Rd St., Leonards, 2065, NSW, Australia
| | | | - Gregory Fulcher
- Royal North Shore Hospital, Reserve Rd St., Leonards, 2065, NSW, Australia
| | - Christopher John Jackson
- Sutton Laboratories Level 10, The Kolling Institute, The University of Sydney, Northern Clinical School, Royal North Shore Hospital, Reserve Rd, St. Leonards, 2065, NSW, Australia
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Gorbacheva LR, Kiseleva EV, Savinkova IG, Strukova SM. A new concept of action of hemostatic proteases on inflammation, neurotoxicity, and tissue regeneration. BIOCHEMISTRY (MOSCOW) 2017; 82:778-790. [DOI: 10.1134/s0006297917070033] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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Essalmani R, Susan-Resiga D, Guillemot J, Kim W, Sachan V, Awan Z, Chamberland A, Asselin MC, Ly K, Desjardins R, Day R, Prat A, Seidah NG. Thrombin activation of protein C requires prior processing by a liver proprotein convertase. J Biol Chem 2017; 292:10564-10573. [PMID: 28468828 DOI: 10.1074/jbc.m116.770040] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Revised: 04/25/2017] [Indexed: 01/29/2023] Open
Abstract
Protein C, a secretory vitamin K-dependent anticoagulant serine protease, inactivates factors Va/VIIIa. It is exclusively synthesized in liver hepatocytes as an inactive zymogen (proprotein C). In humans, thrombin cleavage of the propeptide at PR221↓ results in activated protein C (APC; residues 222-461). However, the propeptide is also cleaved by a furin-like proprotein convertase(s) (PCs) at KKRSHLKR199↓ (underlined basic residues critical for the recognition by PCs), but the order of cleavage is unknown. Herein, we present evidence that at the surface of COS-1 cells, mouse proprotein C is first cleaved by the convertases furin, PC5/6A, and PACE4. In mice, this cleavage occurs at the equivalent site, KKRKILKR198↓, and requires the presence of Arg198 at P1 and a combination of two other basic residues at either P2 (Lys197), P6 (Arg193), or P8 (Lys191) positions. Notably, the thrombin-resistant R221A mutant is still cleaved by these PCs, revealing that convertase cleavage can precede thrombin activation. This conclusion was supported by the fact that the APC-specific activity in the medium of COS-1 cells is exclusively dependent on prior cleavage by the convertases, because both R198A and R221A lack protein C activity. Primary cultures of hepatocytes derived from wild-type or hepatocyte-specific furin, PC5/6, or complete PACE4 knock-out mice suggested that the cleavage of overexpressed proprotein C is predominantly performed by furin intracellularly and by all three proprotein convertases at the cell surface. Indeed, plasma analyses of single-proprotein convertase-knock-out mice showed that loss of the convertase furin or PC5/6 in hepatocytes results in a ∼30% decrease in APC levels, with no significant contribution from PACE4. We conclude that prior convertase cleavage of protein C in hepatocytes is critical for its thrombin activation.
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Affiliation(s)
- Rachid Essalmani
- From the Laboratories of Biochemical Neuroendocrinology, Institut de Recherches Cliniques de Montréal, University of Montreal, Montreal, Quebec H2W 1R7, Canada and
| | - Delia Susan-Resiga
- From the Laboratories of Biochemical Neuroendocrinology, Institut de Recherches Cliniques de Montréal, University of Montreal, Montreal, Quebec H2W 1R7, Canada and
| | - Johann Guillemot
- From the Laboratories of Biochemical Neuroendocrinology, Institut de Recherches Cliniques de Montréal, University of Montreal, Montreal, Quebec H2W 1R7, Canada and
| | - Woojin Kim
- From the Laboratories of Biochemical Neuroendocrinology, Institut de Recherches Cliniques de Montréal, University of Montreal, Montreal, Quebec H2W 1R7, Canada and
| | - Vatsal Sachan
- From the Laboratories of Biochemical Neuroendocrinology, Institut de Recherches Cliniques de Montréal, University of Montreal, Montreal, Quebec H2W 1R7, Canada and
| | - Zuhier Awan
- From the Laboratories of Biochemical Neuroendocrinology, Institut de Recherches Cliniques de Montréal, University of Montreal, Montreal, Quebec H2W 1R7, Canada and
| | - Ann Chamberland
- From the Laboratories of Biochemical Neuroendocrinology, Institut de Recherches Cliniques de Montréal, University of Montreal, Montreal, Quebec H2W 1R7, Canada and
| | - Marie-Claude Asselin
- From the Laboratories of Biochemical Neuroendocrinology, Institut de Recherches Cliniques de Montréal, University of Montreal, Montreal, Quebec H2W 1R7, Canada and
| | - Kévin Ly
- the Institut de Pharmacologie de Sherbrooke, Department of Surgery/Urology Division, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, Quebec J1K 2R1, Canada
| | - Roxane Desjardins
- the Institut de Pharmacologie de Sherbrooke, Department of Surgery/Urology Division, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, Quebec J1K 2R1, Canada
| | - Robert Day
- the Institut de Pharmacologie de Sherbrooke, Department of Surgery/Urology Division, Faculté de Médecine et des Sciences de la Santé, Université de Sherbrooke, Sherbrooke, Quebec J1K 2R1, Canada
| | - Annik Prat
- From the Laboratories of Biochemical Neuroendocrinology, Institut de Recherches Cliniques de Montréal, University of Montreal, Montreal, Quebec H2W 1R7, Canada and
| | - Nabil G Seidah
- From the Laboratories of Biochemical Neuroendocrinology, Institut de Recherches Cliniques de Montréal, University of Montreal, Montreal, Quebec H2W 1R7, Canada and
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Yang Y, Tang H. Aberrant coagulation causes a hyper-inflammatory response in severe influenza pneumonia. Cell Mol Immunol 2016; 13:432-42. [PMID: 27041635 PMCID: PMC4947825 DOI: 10.1038/cmi.2016.1] [Citation(s) in RCA: 111] [Impact Index Per Article: 13.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Revised: 01/06/2016] [Accepted: 01/06/2016] [Indexed: 02/07/2023] Open
Abstract
Influenza A virus (IAV) infects the respiratory tract in humans and causes significant morbidity and mortality worldwide each year. Aggressive inflammation, known as a cytokine storm, is thought to cause most of the damage in the lungs during IAV infection. Dysfunctional coagulation is a common complication in pathogenic influenza, manifested by lung endothelial activation, vascular leak, disseminated intravascular coagulation and pulmonary microembolism. Importantly, emerging evidence shows that an uncontrolled coagulation system, including both the cellular (endothelial cells and platelets) and protein (coagulation factors, anticoagulants and fibrinolysis proteases) components, contributes to the pathogenesis of influenza by augmenting viral replication and immune pathogenesis. In this review, we focus on the underlying mechanisms of the dysfunctional coagulatory response in the pathogenesis of IAV.
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Affiliation(s)
- Yan Yang
- Division of Viral Pathology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China
| | - Hong Tang
- Division of Viral Pathology, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China.,Institute Pasteur of Shanghai, Chinese Academy of Sciences, 320 Yue-yang Road, Shanghai 200031, China
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Thrombomodulin improves rat survival after extensive hepatectomy. J Surg Res 2015; 194:375-382. [DOI: 10.1016/j.jss.2014.10.048] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2014] [Revised: 10/11/2014] [Accepted: 10/29/2014] [Indexed: 01/08/2023]
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Munir MS, Weng LC, Tang W, Basu S, Pankow JS, Matijevic N, Cushman M, Boerwinkle E, Folsom AR. Genetic markers associated with plasma protein C level in African Americans: the atherosclerosis risk in communities (ARIC) study. Genet Epidemiol 2014; 38:709-13. [PMID: 25376901 PMCID: PMC4354842 DOI: 10.1002/gepi.21868] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2014] [Revised: 09/19/2014] [Accepted: 09/30/2014] [Indexed: 11/06/2022]
Abstract
Protein C is an endogenous anticoagulant protein with anti-inflammatory properties. Single-nucleotide polymorphisms (SNPs) affect the levels of circulating protein C in European Americans. We performed a genome-wide association (GWA) scan of plasma protein C concentration with approximately 2.5 million SNPs in 2,701 African Americans in the Atherosclerosis Risk in Communities Study. Seventy-nine SNPs from the 20q11 and 2q14 regions reached the genome-wide significance threshold of 5 × 10(-8) . A missense variant rs867186 in the PROCR gene at 20q11 is known to affect protein C levels in individuals of European descent and showed the strongest signal (P = 9.84 × 10(-65) ) in African Americans. The minor allele of this SNP was associated with higher protein C levels (β = 0.49 μg/ml; 10% variance explained). In the 2q14 region, the top SNPs were near or within the PROC gene: rs7580658 (β = 0.15 μg/ml; 2% variance explained, P = 1.7 × 10(-12) ) and rs1799808 (β = 0.15 μg/ml; 2% variance explained, P = 2.03 × 10(-12) ). These two SNPs were in strong linkage disequilibrium (LD) with another SNP rs1158867 that resides in a biochemically functional site and in weak to strong LD with the top PROC variants previously reported in individuals of European descent. In addition, two variants outside the PROC region were significantly and independently associated with protein C levels: rs4321325 in CYP27C1 and rs13419716 in MYO7B. In summary, this first GWA study for plasma protein C levels in African Americans confirms the associations of SNPs in the PROC and PROCR regions with circulating levels of protein C across ethnic populations and identifies new candidates for protein C regulation.
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Affiliation(s)
- M. Shahzeb Munir
- Division of Preventive Medicine, Mayo Clinic, Rochester Minnesota, USA
- Division of Epidemiology and Community Health, University of Minnesota, Minneapolis, Minnesota, USA
| | - Lu-Chen Weng
- Division of Epidemiology and Community Health, University of Minnesota, Minneapolis, Minnesota, USA
| | - Weihong Tang
- Division of Epidemiology and Community Health, University of Minnesota, Minneapolis, Minnesota, USA
| | - Saonli Basu
- Division of Biostatistics, University of Minnesota, Minneapolis, Minnesota, USA
| | - James S. Pankow
- Division of Epidemiology and Community Health, University of Minnesota, Minneapolis, Minnesota, USA
| | - Nena Matijevic
- Department of Surgery, Medical School, University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - Mary Cushman
- Departments of Medicine and Pathology, University of Vermont, Burlington, Vermont, USA
| | - Eric Boerwinkle
- Human Genetics Center and Institute of Molecular Medicine, University of Texas Health Science Center at Houston, Houston, Texas, USA
| | - Aaron R. Folsom
- Division of Epidemiology and Community Health, University of Minnesota, Minneapolis, Minnesota, USA
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Wijewardena A, Lajevardi SS, Vandervord E, Vandervord J, Lang TC, Fulcher G, Jackson CJ. Activated protein C to heal pressure ulcers. Int Wound J 2014; 13:986-91. [PMID: 25185858 DOI: 10.1111/iwj.12343] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2013] [Revised: 07/02/2014] [Accepted: 07/05/2014] [Indexed: 11/27/2022] Open
Abstract
Pressure ulcers present a major clinical challenge, are physically debilitating and place the patient at risk of serious comorbidities such as septic shock. Recombinant human activated protein C (APC) is an anticoagulant with anti-inflammatory, cytoprotective and angiogenic effects that promote rapid wound healing. Topical negative pressure wound therapy (TNP) has become widely used as a treatment modality in wounds although its efficacy has not been proven through randomised controlled trials. The aim of this study was to determine the preliminary efficacy and safety of treatment with APC for severe chronic pressure sores with and without TNP. This case presentation describes the history, management and outcome of two patients each with a severe chronic non-healing pressure ulcer that had failed to respond to conventional therapy. TNP was added to conservative management of both ulcers with no improvement seen. Then local application of small doses of APC was added to TNP and with conservative management, resulted in significant clinical improvement and rapid healing of both ulcers, displaying rapid growth of vascular granulation tissue with subsequent epithelialisation. Patients tolerated the treatment well and improvements suggested by long-term follow-up were provided. Randomised placebo-controlled double blind trials are needed to quantify the efficacy, safety, cost-effectiveness, optimal dose and quality of life changes seen from treatment with APC.
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Affiliation(s)
- Aruna Wijewardena
- Department of Burns and Plastic and Reconstructive Surgery, Royal North Shore Hospital, St Leonards, Australia
| | - Sepehr S Lajevardi
- Department of Burns and Plastic and Reconstructive Surgery, Royal North Shore Hospital, St Leonards, Australia
| | - Elle Vandervord
- Department of Burns and Plastic and Reconstructive Surgery, Royal North Shore Hospital, St Leonards, Australia
| | - John Vandervord
- Department of Burns and Plastic and Reconstructive Surgery, Royal North Shore Hospital, St Leonards, Australia
| | - Thomas C Lang
- Sutton Research Laboratories, Kolling Institute of Medical Research, University of Sydney, St Leonards, Australia
| | - Gregory Fulcher
- Department of Endocrinology, University of Sydney, Royal North Shore Hospital, St Leonards, Australia
| | - Christopher J Jackson
- Sutton Research Laboratories, Kolling Institute of Medical Research, University of Sydney, St Leonards, Australia.
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Jackson MT, Moradi B, Smith MM, Jackson CJ, Little CB. Activation of matrix metalloproteinases 2, 9, and 13 by activated protein C in human osteoarthritic cartilage chondrocytes. Arthritis Rheumatol 2014; 66:1525-36. [PMID: 24574263 DOI: 10.1002/art.38401] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2013] [Accepted: 02/06/2014] [Indexed: 01/01/2023]
Abstract
OBJECTIVE Levels of activated protein C (APC) are elevated in the synovial fluid of patients with osteoarthritis (OA), and increased APC levels are correlated with the levels of active matrix metalloproteinase 2 (MMP-2). This study sought to investigate whether APC is a relevant protein for activation of MMPs in the degradation of human OA cartilage, and to elucidate its mechanisms of action. METHODS Human articular cartilage was cultured with or without interleukin-1α (IL-1α), in the presence or absence of APC or protein C, and an MMP or serine proteinase inhibitor. Aggrecan and collagen release and chondrocyte gene expression levels were quantified. Aggrecanase and MMP cleavage of aggrecan was examined with neoepitope-specific antibodies, and MMP activity was measured using gelatin zymography and fluorogenic peptide assay. RESULTS In human OA cartilage, APC induced aggrecan and collagen release, whereas in non-OA cartilage, costimulation with IL-1α was required. Inhibition of MMP activity reduced APC-induced cartilage proteolysis, and MMP-induced aggrecanolysis was confirmed by Western blotting. In cultures with APC alone, the activity of MMPs 2, 9, and 13 was significantly increased in OA cartilage, although APC could not directly activate MMPs 2 or 9. Expression of MMP1, MMP2, MMP9, MMP13, TIMP1, and TIMP3 was not altered by APC in OA cartilage. Human OA chondrocytes expressed messenger RNA for protein C, endothelial protein C receptor, thrombomodulin, and protease-activated receptor 1, but these were unaltered or down-regulated by APC. The induction of MMP activation and cartilage degradation by APC was dependent on its serine protease activity. CONCLUSION APC is a physiologically relevant activator of MMPs and cartilage breakdown in human OA. The effects of APC are dependent on its proteolytic activity and as-yet-undefined cell and/or cartilage matrix factors, and inhibition of this pathway may provide a novel therapeutic target to halt the progression of cartilage damage in OA.
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Affiliation(s)
- Miriam T Jackson
- Kolling Institute of Medical Research, University of Sydney, and Royal North Shore Hospital, St. Leonards, New South Wales, Australia
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Anti-inflammatory functions of protein C require RAGE and ICAM-1 in a stimulus-dependent manner. Mediators Inflamm 2014; 2014:743678. [PMID: 24876676 PMCID: PMC4024424 DOI: 10.1155/2014/743678] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2014] [Revised: 03/18/2014] [Accepted: 04/02/2014] [Indexed: 12/30/2022] Open
Abstract
By binding β2-integrins both ICAM-1 and the receptor for advanced glycation end products (RAGE) mediate leukocyte recruitment in a stimulus-dependent manner. Using different inflammatory mouse models we investigated how RAGE and ICAM-1 are involved in anti-inflammatory functions of protein C (PC; Ceprotin, 100 U/kg). We found that, depending on the stimulus, RAGE and ICAM-1 are cooperatively involved in PC-induced inhibition of leukocyte recruitment in cremaster models of inflammation. During short-term proinflammatory stimulation (trauma, fMLP, and CXCL1), ICAM-1 is more important for mediation of anti-inflammatory effects of PC, whereas RAGE plays a major role after longer proinflammatory stimulation (TNFα). In contrast to WT and Icam-1−/− mice, PC had no effect on bronchoalveolar neutrophil emigration in RAGE−/− mice during LPS-induced acute lung injury, suggesting that RAGE critically mediates PC effects during acute lung inflammation. In parallel, PC treatment effectively blocked leukocyte recruitment and improved survival of WT mice and Icam-1-deficient mice in LPS-induced endotoxemia, but failed to do so in RAGE-deficient mice. Exploring underlying mechanisms, we found that PC is capable of downregulating intracellular RAGE and extracellular ICAM-1 in endothelial cells. Taken together, our data show that RAGE and ICAM-1 are required for the anti-inflammatory functions of PC.
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Braach N, Frommhold D, Buschmann K, Pflaum J, Koch L, Hudalla H, Staudacher K, Wang H, Isermann B, Nawroth P, Poeschl J. RAGE controls activation and anti-inflammatory signalling of protein C. PLoS One 2014; 9:e89422. [PMID: 24586767 PMCID: PMC3933550 DOI: 10.1371/journal.pone.0089422] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2013] [Accepted: 01/21/2014] [Indexed: 12/30/2022] Open
Abstract
AIMS The receptor for advanced glycation endproducts, RAGE, is a multiligand receptor and NF-κB activator leading to perpetuation of inflammation. We investigated whether and how RAGE is involved in mediation of anti-inflammatory properties of protein C. METHODS AND RESULTS We analyzed the effect of protein C on leukocyte adhesion and transmigration in WT- and RAGE-deficient mice using intravital microscopy of cremaster muscle venules during trauma- and TNFα-induced inflammation. Both, protein C (PC, Ceprotin, 100 U/kg) and activated protein C (aPC, 24 µg/kg/h) treatment significantly inhibited leukocyte adhesion in WT mice in these inflammation models. The impaired leukocyte adhesion after trauma-induced inflammation in RAGE knockout mice could not be further reduced by PC and aPC. After TNFα-stimulation, however, aPC but not PC treatment effectively blocked leukocyte adhesion in these mice. Consequently, we asked whether RAGE is involved in PC activation. Since RAGE-deficient mice and endothelial cells showed insufficient PC activation, and since thrombomodulin (TM) and endothelial protein C receptor (EPCR) are reduced on the mRNA and protein level in RAGE deficient endothelial cells, an involvement of RAGE in TM-EPCR-dependent PC activation is likely. Moreover, TNFα-induced activation of MAPK and upregulation of ICAM-1 and VCAM-1 are reduced both in response to aPC treatment and in the absence of RAGE. Thus, there seems to be interplay of the RAGE and the PC pathway in inflammation. CONCLUSION RAGE controls anti-inflammatory properties and activation of PC, which might involve EPCR and TM.
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Affiliation(s)
- Natascha Braach
- Department of Neonatology, University Children’s Hospital, Heidelberg, Germany
| | - David Frommhold
- Department of Neonatology, University Children’s Hospital, Heidelberg, Germany
| | - Kirsten Buschmann
- Department of Neonatology, University Children’s Hospital, Heidelberg, Germany
| | - Johanna Pflaum
- Department of Neonatology, University Children’s Hospital, Heidelberg, Germany
| | - Lutz Koch
- Department of Neonatology, University Children’s Hospital, Heidelberg, Germany
| | - Hannes Hudalla
- Department of Neonatology, University Children’s Hospital, Heidelberg, Germany
| | - Kathrin Staudacher
- Department of Neonatology, University Children’s Hospital, Heidelberg, Germany
| | - Hongjie Wang
- Department of Clinical Chemistry and Biochemistry, Otto-von-Guericke-University, Magdeburg, Germany
| | - Berend Isermann
- Department of Clinical Chemistry and Biochemistry, Otto-von-Guericke-University, Magdeburg, Germany
| | - Peter Nawroth
- Department of Medicine I and Clinical Chemistry, University Hospital, Heidelberg, Germany
| | - Johannes Poeschl
- Department of Neonatology, University Children’s Hospital, Heidelberg, Germany
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Julovi SM, Shen K, Mckelvey K, Minhas N, March L, Jackson CJ. Activated protein C inhibits proliferation and tumor necrosis factor α-stimulated activation of p38, c-Jun NH2-terminal kinase (JNK) and Akt in rheumatoid synovial fibroblasts. Mol Med 2013; 19:324-31. [PMID: 24096826 DOI: 10.2119/molmed.2013.00034] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2013] [Accepted: 09/19/2013] [Indexed: 11/06/2022] Open
Abstract
Synovial fibroblast proliferation is a hallmark of the invasive pannus in the rheumatoid joint. Activated protein C (APC) is a natural anticoagulant that exerts antiinflammatory and cyto-protective effects in various diseases via endothelial protein C receptor (EPCR) and proteinase-activated receptor (PAR)-mediated pathways. In this study, we investigated the effect and the underlying cellular signaling mechanisms of APC on proliferation of human rheumatoid synovial fibroblasts (RSFs). We found that APC stimulated proliferation of mouse dermal fibroblasts (MDFs) and normal human dermal fibroblasts (HDFs) by up to 60%, but robustly downregulated proliferation of RSFs. APC induced the phosphorylation of extracellular signal-regulated protein kinase (ERK) and enhanced expression of p21 and p27 in a dose-dependent manner in RSFs. The latter effect was inhibited by pre-treatment with the ERK inhibitors PD98059 and U0126 but not by p38 inhibitor SB203580. In addition, APC significantly downregulated tumor necrosis factor (TNF)α-stimulated cell proliferation and activation of p38, c-Jun NH2-terminal kinase (JNK) and Akt in RSFs. These results provide the first evidence that APC selectively inhibits proliferation and the inflammatory signaling pathways of RSFs. Thus, APC may reduce synovial hyperplasia and pannus invasion in rheumatoid arthritis.
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Affiliation(s)
- Sohel M Julovi
- Sutton Arthritis Research Laboratories, Sydney Medical School, The University of Sydney at Royal North Shore Hospital, St Leonards, Australia.,Department of Surgery, Kolling Institute of Medical Research, Sydney Medical School, The University of Sydney at Royal North Shore Hospital, St Leonards, Australia
| | - Kaitlin Shen
- Sutton Arthritis Research Laboratories, Sydney Medical School, The University of Sydney at Royal North Shore Hospital, St Leonards, Australia
| | - Kelly Mckelvey
- Sutton Arthritis Research Laboratories, Sydney Medical School, The University of Sydney at Royal North Shore Hospital, St Leonards, Australia
| | - Nikita Minhas
- Sutton Arthritis Research Laboratories, Sydney Medical School, The University of Sydney at Royal North Shore Hospital, St Leonards, Australia
| | - Lyn March
- Sutton Arthritis Research Laboratories, Sydney Medical School, The University of Sydney at Royal North Shore Hospital, St Leonards, Australia
| | - Christopher J Jackson
- Sutton Arthritis Research Laboratories, Sydney Medical School, The University of Sydney at Royal North Shore Hospital, St Leonards, Australia
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15
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Activated protein C differentially regulates both viability and differentiation of osteoblasts mediated by bisphosphonates. Exp Mol Med 2013; 45:e9. [PMID: 23412516 PMCID: PMC3584664 DOI: 10.1038/emm.2013.16] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Activated protein C (APC) is a cytoprotective anticoagulant that can promote cutaneous healing. We examined the effect of APC on viability and differentiation of the osteoblastic line, MG63, in the presence and absence of bisphosphonates (BPs). Osteoblasts were cultured and treated for 24 or 48 h with Alendronate (Aln), Zoledronate (Zol) or Pamidronate (Pam) at concentrations ranging from 10−4 to 10−6 ℳ. Cell differentiation was measured using type 1 collagen production, Alizarin red staining and alkaline phosphatase activity, whereas cell viability was assessed using MTT and crystal violet assays. All three BPs induced MG63 cell death in a dose- and time-dependent manner. Pam- and Zol-related cell death was prevented by APC treatment; however, cell death induced by Aln was accelerated by APC. APC induced MG63 cell differentiation that was enhanced by Aln, but inhibited by Pam or Zol. Endothelial protein C receptor (EPCR) was expressed by MG63 cells and mediated the protective effect of APC on Zol-induced viability. In summary, we have demonstrated that (1) APC favorably regulates MG63 viability and differentiation toward bone growth, (2) APC differentially regulates the effects of specific BPs and (3) at least part of the effects of APC is mediated through EPCR. These findings highlight the potential importance of the PC pathway in bone physiology and provide strong evidence that APC may influence bone cells and has potential to be a therapeutic drug for bone regeneration, depending on concurrent BP treatment.
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16
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Tang W, Schwienbacher C, Lopez L, Ben-Shlomo Y, Oudot-Mellakh T, Johnson A, Samani N, Basu S, Gögele M, Davies G, Lowe G, Tregouet DA, Tan A, Pankow J, Tenesa A, Levy D, Volpato C, Rumley A, Gow A, Minelli C, Yarnell J, Porteous D, Starr J, Gallacher J, Boerwinkle E, Visscher P, Pramstaller P, Cushman M, Emilsson V, Plump A, Matijevic N, Morange PE, Deary I, Hicks A, Folsom A. Genetic associations for activated partial thromboplastin time and prothrombin time, their gene expression profiles, and risk of coronary artery disease. Am J Hum Genet 2012; 91:152-62. [PMID: 22703881 DOI: 10.1016/j.ajhg.2012.05.009] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2011] [Revised: 04/10/2012] [Accepted: 05/05/2012] [Indexed: 10/28/2022] Open
Abstract
Activated partial thromboplastin time (aPTT) and prothrombin time (PT) are clinical tests commonly used to screen for coagulation-factor deficiencies. One genome-wide association study (GWAS) has been reported previously for aPTT, but no GWAS has been reported for PT. We conducted a GWAS and meta-analysis to identify genetic loci for aPTT and PT. The GWAS for aPTT was conducted in 9,240 individuals of European ancestry from the Atherosclerosis Risk in Communities (ARIC) study, and the GWAS for PT was conducted in 2,583 participants from the Genetic Study of Three Population Microisolates in South Tyrol (MICROS) and the Lothian Birth Cohorts (LBC) of 1921 and 1936. Replication was assessed in 1,041 to 3,467 individuals. For aPTT, previously reported associations with KNG1, HRG, F11, F12, and ABO were confirmed. A second independent association in ABO was identified and replicated (rs8176704, p = 4.26 × 10(-24)). Pooling the ARIC and replication data yielded two additional loci in F5 (rs6028, p = 3.22 × 10(-9)) and AGBL1 (rs2469184, p = 3.61 × 10(-8)). For PT, significant associations were identified and confirmed in F7 (rs561241, p = 3.71 × 10(-56)) and PROCR/EDEM2 (rs2295888, p = 5.25 × 10(-13)). Assessment of existing gene expression and coronary artery disease (CAD) databases identified associations of five of the GWAS loci with altered gene expression and two with CAD. In summary, eight genetic loci that account for ∼29% of the variance in aPTT and two loci that account for ∼14% of the variance in PT were detected and supported by functional data.
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17
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Protein C anticoagulant and cytoprotective pathways. Int J Hematol 2012; 95:333-45. [PMID: 22477541 DOI: 10.1007/s12185-012-1059-0] [Citation(s) in RCA: 87] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2012] [Revised: 03/09/2012] [Accepted: 03/14/2012] [Indexed: 12/11/2022]
Abstract
Plasma protein C is a serine protease zymogen that is transformed into the active, trypsin-like protease, activated protein C (APC), which can exert multiple activities. For its anticoagulant action, APC causes inactivation of the procoagulant cofactors, factors Va and VIIIa, by limited proteolysis, and APC's anticoagulant activity is promoted by protein S, various lipids, high-density lipoprotein, and factor V. Hereditary heterozygous deficiency of protein C or protein S is linked to moderately increased risk for venous thrombosis, while a severe or total deficiency of either protein is linked to neonatal purpura fulminans. In recent years, the beneficial direct effects of APC on cells which are mediated by several specific receptors have become the focus of much attention. APC-induced signaling can promote multiple cytoprotective actions which can minimize injuries in various preclinical animal injury models. Remarkably, pharmacologic therapy using APC demonstrates substantial neuroprotective effects in various murine injury models, including ischemic stroke. This review summarizes the molecules that are central to the protein C pathways, the relationship of pathway deficiencies to venous thrombosis risk, and mechanisms for the beneficial effects of APC.
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18
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Xue M, Dervish S, Harrison LC, Fulcher G, Jackson CJ. Activated protein C inhibits pancreatic islet inflammation, stimulates T regulatory cells, and prevents diabetes in non-obese diabetic (NOD) mice. J Biol Chem 2012; 287:16356-64. [PMID: 22447930 DOI: 10.1074/jbc.m111.325951] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
Activated protein C (aPC) is a natural anticoagulant with strong cyto-protective and anti-inflammatory properties. aPC inhibits pancreatic inflammation and preserves functional islets after intraportal transplantation in mice. Whether aPC prevents the onset or development of type 1 diabetes (T1D) is unknown. In this study, when human recombinant aPC was delivered intraperitoneally, twice weekly for 10 weeks (from week 6 to 15) to non-obese diabetic (NOD) mice, a model for T1D, the incidence of diabetes was reduced from 70% (saline control) to 7.6% by 26 weeks of age. Islets of aPC-treated mice exhibited markedly increased expression of insulin, aPC/protein C, endothelial protein C receptor, and matrix metalloproteinase (MMP)-2 when examined by immunostaining. The insulitis score in aPC-treated mice was 50% less than that in control mice. T regulatory cells (Tregs) in the spleen, pancreatic islets, and pancreatic lymph nodes were increased 37, 53, and 59%, respectively, in NOD mice following aPC treatment. These Tregs had potent suppressor function and, after adoptive transfer, delayed diabetes onset in NOD.severe combined immunodeficiency mice. The culture of NOD mouse spleen cells with aPC reduced the secretion of inflammatory cytokines interleukin (IL)-1β and interferon-γ but increased IL-2 and transforming growth factor-β1, two cytokines required for Treg differentiation. In summary, our results indicate that aPC prevents T1D in the NOD mouse. The aPC mechanism of action is complex, involving induction of Treg differentiation, inhibition of inflammation, and possibly direct cyto-protective effects on β cells.
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Affiliation(s)
- Meilang Xue
- Sutton Arthritis Research Laboratories, University of Sydney at Royal North Shore Hospital, St. Leonards, New South Wales 2065, Australia.
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19
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Wondimu A, Weir L, Robertson D, Mezentsev A, Kalachikov S, Panteleyev AA. Loss of Arnt (Hif1β) in mouse epidermis triggers dermal angiogenesis, blood vessel dilation and clotting defects. J Transl Med 2012; 92:110-24. [PMID: 21946855 DOI: 10.1038/labinvest.2011.134] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Targeted ablation of Aryl hydrocarbon receptor nuclear translocator (Arnt) in the mouse epidermis results in severe abnormalities in dermal vasculature reminiscent of petechia induced in human skin by anticoagulants or certain genetic disorders. Lack of Arnt leads to downregulation of Egln3/Phd3 hydroxylase and concomitant hypoxia-independent stabilization of hypoxia-induced factor 1α (Hif1α) along with compensatory induction of Arnt2. Ectopic induction of Arnt2 results in its heterodimerization with stabilized Hif1α and is associated with activation of genes coding for secreted proteins implicated in control of angiogenesis, coagulation, vasodilation and blood vessel permeability such as S100a8/S100a9, S100a10, Serpine1, Defb3, Socs3, Cxcl1 and Thbd. Since ARNT and ARNT2 heterodimers with HIF1α are known to have different (yet overlapping) downstream targets our findings suggest that loss of Arnt in the epidermis activates an aberrant paracrine regulatory pathway responsible for dermal vascular phenotype in K14-Arnt KO mice. This assumption is supported by a significant decline of von Willebrand factor in dermal vasculature of these mice where Arnt level remains normal. Given the essential role of ARNT in the adaptive response to environmental stress and striking similarity between skin vascular phenotype in K14-Arnt KO mice and specific vascular features of tumour stroma and psoriatic skin, we believe that further characterization of Arnt-dependent epidermal-dermal signalling may provide insight into the role of macro- and micro-environmental factors in control of skin vasculature and in pathogenesis of environmentally modulated skin disorders.
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Affiliation(s)
- Assefa Wondimu
- Department of Dermatology, Columbia University, New York, NY, USA
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20
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Frommhold D, Tschada J, Braach N, Buschmann K, Doerner A, Pflaum J, Stahl MS, Wang H, Koch L, Sperandio M, Bierhaus A, Isermann B, Poeschl J. Protein C concentrate controls leukocyte recruitment during inflammation and improves survival during endotoxemia after efficient in vivo activation. THE AMERICAN JOURNAL OF PATHOLOGY 2011; 179:2637-50. [PMID: 21907691 DOI: 10.1016/j.ajpath.2011.07.023] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2011] [Revised: 06/18/2011] [Accepted: 07/13/2011] [Indexed: 01/13/2023]
Abstract
Anti-inflammatory properties of protein C (PC) concentrate are poorly studied compared to activated protein C, although PC is suggested to be safer in clinical use. We investigated how PC interferes with the leukocyte recruitment cascade during acute inflammation and its efficacy during murine endotoxemia. We found that similar to activated protein infusion, intravenous PC application reduced leukocyte recruitment in inflamed tissues in a dose- and time-dependent manner. During both tumor necrosis factor-α induced and trauma-induced inflammation of the cremaster muscle, intravital microscopy revealed that leukocyte adhesion and transmigration, but not rolling, were profoundly inhibited by 100 U/kg PC. Moreover, PC blocked leukocyte emigration into the bronchoalveolar space during lipopolysaccharide (LPS) induced acute lung injury. PC was efficiently activated in a murine endotoxemia model, which reduced leukocyte infiltration of organs and strongly improved survival (75% versus 25% of control mice). Dependent on the inflammatory model, PC provoked a significant inhibition of leukocyte recruitment as early as 1 hour after administration. PC-induced inhibition of leukocyte recruitment during acute inflammation critically involves thrombomodulin-mediated PC activation, subsequent endothelial PC receptor and protease-activated receptor-1-dependent signaling, and down-regulation of intercellular adhesion molecule 1 leading to reduced endothelial inflammatory response. We conclude that during acute inflammation and sepsis, PC is a fast acting and effective therapeutic approach to block leukocyte recruitment and improve survival.
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Affiliation(s)
- David Frommhold
- Department of Neonatology, University Children's Hospital, Heidelberg, Germany.
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Protease activated receptor-2 mediates activated protein C-induced cutaneous wound healing via inhibition of p38. THE AMERICAN JOURNAL OF PATHOLOGY 2011; 179:2233-42. [PMID: 21907694 DOI: 10.1016/j.ajpath.2011.07.024] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2011] [Revised: 07/11/2011] [Accepted: 07/19/2011] [Indexed: 01/28/2023]
Abstract
Activated protein C (APC) is a natural anticoagulant that exerts anti-inflammatory and cytoprotective properties mediated through the protease activated receptor (PAR)-1. APC can also proteolytically cleave PAR-2, although subsequent function is unknown. On the basis of recent evidence that APC promotes wound healing, the aim of this study was to determine whether APC acts through PARs to heal murine excisional wounds or to regulate human cultured keratinocyte function and to determine the signaling mechanisms. Topical administration of APC accelerated wound healing in wild-type mice and, unexpectedly, in PAR-1 knockout mice. PAR-2 knockout mice healed significantly slower than wild-type mice, and healing was not altered by adding APC, indicating that APC acts through PAR-2 to heal wounds. In cultured human primary keratinocytes, APC enhanced PAR-2, stimulated proliferation, activated phosphatidylinositol 3-kinase/Src/Akt, and inhibited phosphorylated (P)-p38. Inhibiting PAR-1 or PAR-2, by small-interfering RNA or blocking antibody, reversed APC-induced keratinocyte proliferation and Akt activation. Blocking PAR-2, but not PAR-1, reversed the inhibition of P-p38 by APC. Furthermore, inhibition of P-p38 accelerated wound healing in wild-type mice. In summary, although APC acts through both PAR-1 and PAR-2 to activate Akt and to increase keratinocyte proliferation, APC-induced murine wound healing depends on PAR-2 activity and inhibition of P-p38.
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Chatrou MLL, Reutelingsperger CP, Schurgers LJ. Role of vitamin K-dependent proteins in the arterial vessel wall. Hamostaseologie 2011; 31:251-7. [PMID: 21713318 DOI: 10.5482/ha-1157] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2011] [Accepted: 06/06/2011] [Indexed: 12/20/2022] Open
Abstract
Vitamin K was discovered early last century at the same time as the vitamin K-antagonists. For many years the role of vitamin K was solely ascribed to coagulation and coagulation was thought to be involved only at the venous blood side. This view has dramatically changed with the discovery of vitamin K-dependent proteins outside the coagulation cascade and the role of coagulation factors at the arterial side. Vitamin K-dependent proteins are involved in the regulation of vascular smooth muscle cell migration, apoptosis, and calcification. Vascular calcification has become an important independent predictor of cardiovascular disease. Vitamin K-antagonists induce inactivity of inhibitors of vascular calcification, leading to accelerated calcification. The involvement of vitamin K-dependent proteins such as MGP in vascular calcification make that calcification is amendable for intervention with high intake of vitamin K. This review focuses on the effect of vitamin K-dependent proteins in vascular disease.
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Affiliation(s)
- M L L Chatrou
- Dept. of Biochemistry, Maastricht University, Maastricht, The Netherlands
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Bijak M, Bobrowski M, Borowiecka M, Podsędek A, Golański J, Nowak P. Anticoagulant effect of polyphenols-rich extracts from black chokeberry and grape seeds. Fitoterapia 2011; 82:811-7. [PMID: 21596108 DOI: 10.1016/j.fitote.2011.04.017] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2010] [Revised: 04/18/2011] [Accepted: 04/23/2011] [Indexed: 11/15/2022]
Abstract
Blood coagulation consists of a series of zymogens that can be converted by limited proteolysis to active enzymes leading to the generation of thrombin. Fresh plasma and human thrombin was incubated with extracts from berries of Aronia melanocarpa or seeds of Vitis vinifera (0.5; 5; 50 μg/ml). The in vitro experiments showed that both extracts prolonged clotting time and decreased the maximal velocity of fibrin polymerization in human plasma. Moreover thrombin incubation with both extracts results in the inhibition of amidolytic activity of this enzyme. It gives hopes for development of diet supplements, which may be preventing thrombosis in pathological states.
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Affiliation(s)
- Michał Bijak
- Department of General Biochemistry, University of Lodz, Banacha12/16, 90-237 Lodz, Poland.
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Xue M, Chow SO, Dervish S, Chan YKA, Julovi SM, Jackson CJ. Activated protein C enhances human keratinocyte barrier integrity via sequential activation of epidermal growth factor receptor and Tie2. J Biol Chem 2010; 286:6742-50. [PMID: 21173154 DOI: 10.1074/jbc.m110.181388] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Keratinocytes play a critical role in maintaining epidermal barrier function. Activated protein C (APC), a natural anticoagulant with anti-inflammatory and endothelial barrier protective properties, significantly increased the barrier impedance of keratinocyte monolayers, measured by electric cell substrate impedance sensing and FITC-dextran flux. In response to APC, Tie2, a tyrosine kinase receptor, was rapidly activated within 30 min, and relocated to cell-cell contacts. APC also increased junction proteins zona occludens, claudin-1 and VE-cadherin. Inhibition of Tie2 by its peptide inhibitor or small interfering RNA abolished the barrier protective effect of APC. Interestingly, APC did not activate Tie2 through its major ligand, angiopoietin-1, but instead acted by binding to endothelial protein C receptor, cleaving protease-activated receptor-1 and transactivating EGF receptor. Furthermore, when activation of Akt, but not ERK, was inhibited, the barrier protective effect of APC on keratinocytes was abolished. Thus, APC activates Tie2, via a mechanism requiring, in sequential order, the receptors, endothelial protein C receptor, protease-activated receptor-1, and EGF receptor, which selectively enhances the PI3K/Akt signaling to enhance junctional complexes and reduce keratinocyte permeability.
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Affiliation(s)
- Meilang Xue
- Sutton Arthritis Research Laboratories, Kolling Institute of Medical Research, University of Sydney at Royal North Shore Hospital, St. Leonards, New South Wales 2065, Australia.
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25
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Novel insights into molecular mechanisms of abruption-induced preterm birth. Expert Rev Mol Med 2010; 12:e35. [PMID: 21040617 DOI: 10.1017/s1462399410001675] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Preterm birth (PTB) complicates more than 12% of all deliveries. Despite significant research, the aetiology of most cases of PTB remains elusive. Two major antecedents of PTB, intra-amniotic infection and decidual haemorrhage (abruption), can exhibit dissimilar demographic and genetic predispositions, despite sharing common molecular and cellular pathways. The use of high-throughput, high-dimensional technologies reveals substantial crosstalk between the coagulation and inflammation pathways. Tissue factor, thrombin and cytokines are key mediators of this crosstalk. Abruptions are associated with excess thrombin generated from decidual-cell-expressed tissue factor. Although thrombin is a primary mediator of the coagulation cascade, it can also promote inflammation-associated PTB by enhancing expression of matrix metalloproteinase and neutrophil-chemoattracting and -activating chemokines. Here, we provide novel insights into the molecular mechanisms and pathways leading to PTB in the setting of placental abruption.
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Genome-wide association study identifies novel loci for plasma levels of protein C: the ARIC study. Blood 2010; 116:5032-6. [PMID: 20802025 DOI: 10.1182/blood-2010-05-283739] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Protein C is an important endogenous anticoagulant in hemostasis. Deficiencies of protein C due to genetic mutations or a low level of circulating protein C increase the risk of venous thromboembolism. We performed a genome-wide association scan for plasma protein C antigen concentration with approximately 2.5 million single-nucleotide polymorphisms in 8048 individuals of European ancestry and a replication analysis in a separate sample of 1376 individuals in the Atherosclerosis Risk in Communities Study. Four independent loci from 3 regions were identified with genome-wide significance: 2p23 (GCKR, best SNP rs1260326, P = 2.04 × 10(-17)), 2q13-q14 (PROC, rs1158867, P = 3.77 × 10(-36)), 20q11 (near and within PROCR, rs8119351, P = 2.68 × 10(-203)), and 20q11.22 (EDEM2, rs6120849, P = 7.19 × 10(-37) and 5.23 × 10(-17) before and after conditional analysis, respectively). All 4 loci replicated in the independent sample. Furthermore, pooling the discovery and replication sets yielded an additional locus at chromosome 7q11.23 (BAZ1B, rs17145713, P = 2.83 × 10(-8)). The regions marked by GCKR, EDEM2, and BAZ1B are novel loci that have not been previously reported for association with protein C concentration. In summary, this first genome-wide scan for circulating protein C concentration identified both new and known loci in the general population. These findings may improve the understanding of physiologic mechanisms in protein C regulation.
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Xue M, Minhas N, Chow SO, Dervish S, Sambrook PN, March L, Jackson CJ. Endogenous protein C is essential for the functional integrity of human endothelial cells. Cell Mol Life Sci 2010; 67:1537-46. [PMID: 20127387 PMCID: PMC11115832 DOI: 10.1007/s00018-010-0269-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2009] [Revised: 12/04/2009] [Accepted: 01/11/2010] [Indexed: 10/19/2022]
Abstract
Circulating protein C (PC) plays a vital role as an anti-coagulant and anti-inflammatory mediator. We show here that human endothelial cells produce PC that acts through novel mediators to enhance their own functional integrity. When endogenous PC or its receptor, endothelial protein C receptor (EPCR), was suppressed by small interfering (si) RNA, human umbilical cord endothelial cell (HUVEC) proliferation was decreased and apoptosis elevated. Interestingly, PC or EPCR siRNA significantly increased HUVEC permeability, which is likely via reduction of the angiopoietin (Ang)1/Ang2 ratio and inhibition of the peripheral localization of the tight junction protein, zona occludins-1. In addition, PC or EPCR siRNA inhibited type IV collagen and matrix metalloproteinase-2, providing the first evidence that PC contributes to vascular basement membrane formation. These newly described actions of endogenous PC act to stabilize endothelial cells and enhance barrier function, to potentially promote the functional integrity of blood vessels.
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Affiliation(s)
- Meilang Xue
- Sutton Research Laboratories, Institute of Bone and Joint Research, Kolling Institute of Medical Research, The University of Sydney at Royal North Shore Hospital, Level 10, The Kolling Building, St Leonards, NSW 2065, Australia.
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Gorbacheva L, Pinelis V, Ishiwata S, Strukova S, Reiser G. Activated protein C prevents glutamate- and thrombin-induced activation of nuclear factor-kappaB in cultured hippocampal neurons. Neuroscience 2010; 165:1138-46. [PMID: 19931359 DOI: 10.1016/j.neuroscience.2009.11.027] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2009] [Revised: 11/10/2009] [Accepted: 11/11/2009] [Indexed: 11/29/2022]
Abstract
Brain injury is associated with neuroinflammation, neurodegeneration, and also blood coagulation with thrombin formation and generation of activated protein C (APC). We have previously shown that APC, a serine protease of hemostasis, at very low concentrations has protective effects in rat hippocampal and cortical neurons at glutamate-induced excitotoxicity through protease-activated receptor-1 (PAR-1) or endothelial receptor of protein C (EPCR)/PAR-1. The transcription factor nuclear factor kappaB (NF-kappaB) takes part in regulating neuronal survival in several pathological conditions. To elucidate the impact of NF-kappaB in APC-mediated cell survival, we investigated nuclear translocation of NF-kappaB p65 at glutamate- or thrombin-induced toxicity in hippocampal neurons. We used immunoassay and immunostaining with confocal microscopy with anti-NF-kappaBp65 antibody. We show that APC at concentrations as low as 1-2 nM inhibits translocation of NF-kappaB p65 into the nucleus of cultured rat hippocampal neurons, induced by 100 muM glutamate or 50 nM thrombin (but not 10 nM). The blocking effect of APC on NF-kappaB p65 translocation was observed at 1 and 4 h after treatment of neurons with glutamate, when the NF-kappaBp 65 level in the nucleus was significantly above the basal level. Then we investigated whether the binding of APC to EPCR/PAR-1 is required to control NF-kappaB activation. Antibodies blocking PAR-1 (ATAP2) or EPCR (P-20) abolished the APC-induced decrease of nuclear level of NF-kappaB p65 at glutamate-induced toxicity, whereas control antibodies to PAR-1 (S-19) and EPCR (IgG) exerted no effect. Thus, we suggest that the activation of NF-kappaB in rat hippocampal neurons mediates the glutamate- and thrombin-activated cell death program, which is reduced by exposure of cells to APC. APC induces the reduction of the nuclear level of NF-kappaB p65 in hippocampal neurons at glutamate-induced excitotoxicity via binding to EPCR and subsequent PAR-1 activation and signaling.
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Affiliation(s)
- L Gorbacheva
- Lomonosov Moscow State University, Department of Human and Animal Physiology, Moscow, Russia
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Administration of human protein C improves survival in an experimental model of sepsis*. Crit Care Med 2010; 38:209-16. [DOI: 10.1097/ccm.0b013e3181b4a972] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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McCann JC, Ames BN. Vitamin K, an example of triage theory: is micronutrient inadequacy linked to diseases of aging? Am J Clin Nutr 2009; 90:889-907. [PMID: 19692494 DOI: 10.3945/ajcn.2009.27930] [Citation(s) in RCA: 129] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
The triage theory posits that some functions of micronutrients (the approximately 40 essential vitamins, minerals, fatty acids, and amino acids) are restricted during shortage and that functions required for short-term survival take precedence over those that are less essential. Insidious changes accumulate as a consequence of restriction, which increases the risk of diseases of aging. For 16 known vitamin K-dependent (VKD) proteins, we evaluated the relative lethality of 11 known mouse knockout mutants to categorize essentiality. Results indicate that 5 VKD proteins that are required for coagulation had critical functions (knockouts were embryonic lethal), whereas the knockouts of 5 less critical VKD proteins [osteocalcin, matrix Gla protein (Mgp), growth arrest specific protein 6, transforming growth factor beta-inducible protein (Tgfbi or betaig-h3), and periostin] survived at least through weaning. The VKD gamma-carboxylation of the 5 essential VKD proteins in the liver and the 5 nonessential proteins in nonhepatic tissues sets up a dichotomy that takes advantage of the preferential distribution of dietary vitamin K1 to the liver to preserve coagulation function when vitamin K1 is limiting. Genetic loss of less critical VKD proteins, dietary vitamin K inadequacy, human polymorphisms or mutations, and vitamin K deficiency induced by chronic anticoagulant (warfarin/coumadin) therapy are all linked to age-associated conditions: bone fragility after estrogen loss (osteocalcin) and arterial calcification linked to cardiovascular disease (Mgp). There is increased spontaneous cancer in Tgfbi mouse knockouts, and knockdown of Tgfbi causes mitotic spindle abnormalities. A triage perspective reinforces recommendations of some experts that much of the population and warfarin/coumadin patients may not receive sufficient vitamin K for optimal function of VKD proteins that are important to maintain long-term health.
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Affiliation(s)
- Joyce C McCann
- Children's Hospital Oakland Research Institute, Oakland, CA 94609, USA.
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Abstract
The horseshoe crab is often referred to as a "living fossil," representative of the oldest classes of arthropods, almost identical to species in existence more than 500 million years ago. Comparative analyses of the defense mechanisms used by the horseshoe crab that allowed it to survive mostly unchanged throughout the millennia reveal a common ancestry of the coagulation and innate immune systems that are totally integrated-indeed, almost inseparable. In human biology, we traditionally view the hemostatic pathways and those regulating innate immune responses to infections and tissue damage as entirely separate entities. But are they? The last couple of decades have revealed a remarkable degree of interplay between these systems, and the linking cellular and molecular mechanisms are rapidly being delineated. In this review, we present some of the major points of intersection between coagulation and innate immunity. We attempt to highlight the potential impact of these findings by identifying recently established paradigms that will hopefully result in the emergence of new strategies to treat a range of inflammatory and hemostatic disorders.
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Milner JM, Patel A, Rowan AD. Emerging roles of serine proteinases in tissue turnover in arthritis. ACTA ACUST UNITED AC 2009; 58:3644-56. [PMID: 19035508 DOI: 10.1002/art.24046] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- J M Milner
- Musculoskeletal Research Group, Institute of Cellular Medicine, Newcastle University, Newcastle upon Tyne, UK.
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Abstract
BACKGROUND Remarkable progress has been made during the last decade in defining the molecular mechanisms that underlie septic shock. This rapidly expanding field is leading to new therapeutic opportunities in the management of severe sepsis. AIM To provide the clinician with a timely summary of the molecular biology of sepsis and to better understand recent advances in sepsis research. DATA SELECTION Medline search of relevant publications in basic mechanisms of sepsis/severe sepsis/septic shock, and selected literature review of other manuscripts about the signalosome, inflammasome, apoptosis, or mechanisms of shock. DATA SYNTHESIS AND FINDINGS: The identification of the toll-like receptors and the associated concept of innate immunity based upon pathogen- or damage-associated molecular pattern molecules allowed significant advances in our understanding of the pathophysiology of sepsis. The essential elements of the inflammasome and signal transduction networks responsible for activation of the host response have now been characterized. Apoptosis, mitochondrial dysfunction, sepsis-related immunosuppression, late mediators of systemic inflammation, control mechanisms for coagulation, and reprogramming of immune response genes all have critical roles in the development of sepsis. CONCLUSIONS Many of these basic discoveries have direct implications for the clinical management of sepsis. The translation of these "bench-to-bedside" findings into new therapeutic strategies is already underway. This brief review provides the clinician with a primer into the basic mechanisms responsible for the molecular biology of sepsis, severe sepsis, and septic shock.
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