Schreiber A.,Experimental and Clinical Research Center |
Schreiber A.,Charité - Medical University of Berlin |
Luft F.C.,Experimental and Clinical Research Center |
Kettritz R.,Experimental and Clinical Research Center |
Kettritz R.,Charité - Medical University of Berlin
Journal of the American Society of Nephrology | Year: 2015
ANCA-activated phagocytes cause vasculitis and necrotizing crescentic GN (NCGN). ANCA-induced phagocyte NADPH oxidase (Phox) may contribute by generating tissue-damaging reactive oxygen species. We tested an alternative hypothesis, in which Phox restrains inflammation by downregulating caspase-1, thereby reducing IL-1β generation and limiting NCGN. In an antimyeloperoxidase (anti-MPO) antibody-mediated disease model, mice transplanted with either gp91phox-deficient or p47phox-deficient bone marrow showed accelerated disease with increased crescents, necrosis, glomerular monocytes, and renal IL-1β levels compared with mice transplanted with wild-type bone marrow. IL-1β receptor blockade abrogated aggravated NCGN in gp91phox-deficient mice. In vitro, challenge with anti-MPO antibody strongly enhanced caspase-1 activity and IL-1β generation in gp91phox-deficient and p47phox-deficient monocytes compared with wild-type monocytes. This enhanced IL-1β generation was abrogated when caspase-1 was blocked. ANCA-induced superoxide and IL-1β generation were inversely related in human monocytes. Furthermore, transplantation of gp91phox/caspase-1 double-deficient bone marrow rescued the accelerated NCGN phenotype in gp91phox bone marrow-deficient mice. These results suggest that Phox-generated reactive oxygen species downregulate caspase-1, thereby keeping the inflammasome in check and limiting ANCA-induced inflammation. IL-1 receptor blockade may provide a promising strategy in NCGN, whereas our data question the benefit of antioxidants. Copyright © 2015 by the American Society of Nephrology.
Verlohren S.,Charité - Medical University of Berlin |
Stepan H.,University of Leipzig |
Dechend R.,Experimental and Clinical Research Center
Clinical Science | Year: 2012
The pathogenesis of pre-eclampsia is still not completely known; however, in the recent decade, there have been tremendous research efforts leading to impressive results highlighting the role of a disturbed angiogenic balance as one of the key features of the disease. Numerous studies have shown the key role of the placenta in the pathogenesis of pre-eclampsia. A shift in the sFlt-1 (soluble Fms-like tyrosine kinase-1)/PlGF (placental growth factor) ratio is associated with the disease. Although pre-eclampsia seems to be a clearly defined disease, clinical presentation, and particularly the dynamics of the clinical course, can vary enormously. The only available tools to diagnose pre-eclampsia are blood pressure measurement and urine protein sampling. However, these tools have a low sensitivity and specificity regarding the prediction of the course of the disease or maternal and perinatal outcomes. The only cure for the disease is delivery, although a timely diagnosis helps in decreasing maternal and fetal morbidity and mortality. The sFlt1/PlGF ratio is able to give additional valuable information on the status and progression of the disease and is apt to be implemented in the diagnostic algorithm of pre-eclampsia. In the present review, we aim to provide an overview of the vast literature on angiogenesis and anti-angiogenesis factors in pre-eclampsia that have been published over the last decade. We introduce work from basic research groups who have focused on the pathophysiological basis of the disease. Furthermore, we review studies with a clinical focus in which the sFlt-1/PlGF ratio has been analysed along with other candidates for routine clinical assessment of pre-eclampsia. © The Authors Journal compilation. © 2012 Biochemical Society.
Luft F.C.,Experimental and Clinical Research Center
Journal of the American Society of Hypertension | Year: 2012
This review of the relationship between aortic stiffness and blood pressure is based on several presentations made at the 2012 Council of High Blood Pressure Research. New information regarding genetic factors and molecular mechanisms involved in altering vascular responses are reviewed as a preview of emerging information in this area. © 2012 American Society of Hypertension. All rights reserved.
Sperling S.R.,Experimental and Clinical Research Center
Cardiovascular Research | Year: 2011
Even though the foundation of systems biology approaches to cardiac function was led more than fifty years ago, there has been slow progression over the last few decades. Systems biology studies were mainly focused on lower organisms, frequently on yeast. With the boost of high-throughput technologies, systems level analyses, building one backbone of systems biology, started to complement the single-gene focus in the fields of heart development and congenital heart disease. A challenge is to bring together the many uncovered molecular components driving heart development and eventually to establish computational models describing this complex developmental process. Congenital heart diseases represent overlapping phenotypes, reflecting the modularity of heart development. The aetiology of the majority of congenital heart disease is still unknown, and it is suggestive that understanding the biological network underlying heart development will enhance our understanding for its alteration. This review provides an overview of the framework for systems biology approaches focusing on the developing heart and its pathology. Recent methodological developments building the basis for future studies are highlighted and the knowledge gained is specified. © 2011 The Author.
Becker M.,Charite University Childrens Hospital |
Galler A.,Charite University Childrens Hospital |
Raile K.,Charite University Childrens Hospital |
Raile K.,Experimental and Clinical Research Center
Pediatrics | Year: 2014
For pediatric patients with hepatocyte nuclear factor-1A (HNF1A) - maturity-onset diabetes of the young (MODY 3), treatment with sulfonylureas is recommended. In adults with HNF1A-MODY, meglitinide analogues achieve lower postprandial glucose levels and pose a lower risk of delayed hypoglycemia compared with sulfonylureas. This therapy has not yet been reviewed in pediatric patients. We report on meglitinide analogue treatment in 3 adolescents with HNF1A-MODY. Case 1 (14-year-old girl) was diagnosed asymptomatically but had an hemoglobin A1c (HbA1c) level of 7.4%; her father had been recently diagnosed with HNF1A-MODY. With repaglinide, her HbA1c level decreased to 5.5%, with no hypoglycemic episodes. Case 2 (14-yearold boy) was diagnosed incidentally with glucosuria (HbA1c level: 7.0%) and was treated with insulin. After the HNF1A-MODY diagnosis, he was switched to glibenclamide. Due to several hypoglycemic episodes, treatment was changed to nateglinide and his HbA1c level decreased to 6.2% with no further hypoglycemic episodes. Case 3 (11-year-old girl) presented with polyuria and polydipsia (HbA1c level: 10.1%) and was initially treated with insulin. After the HNF1A-MODY diagnosis, treatment was changed to repaglinide. She was obese (BMI: 28.8 kg/m2; z-score: +2.2), and glucose control with repaglinide alone was insufficient. Therefore, neutral protamine Hagedorn insulin (0.27 U/kg per day) was added. With this combination therapy, her HbA1c level decreased to 8.2%. The use of meglitinides in these 3 adolescent patients was well tolerated and effective. Furthermore, hypoglycemic episodes were rare compared with treatment with insulin or sulfonylureas. We therefore suggest considering meglitinides as the primary oral treatment option for adolescents suffering from HNF1A-MODY. Copyright © 2014 by the American Academy of Pediatrics.
Mehling H.,Experimental and Clinical Research Center |
Busjahn A.,HealthTwiSt GmbH
Nutrients | Year: 2013
Prevalence of infections by Helicobacter pylori, a pathogen involved in a number of gastrointestinal diseases, remains high in developing countries. Management of infections by eradication is not always an option. Lactobacillus reuteri (L. reuteri) DSMZ17648 (Pylopass™/Lonza) specifically co-aggregates H. pylori in vitro and was shown to reduce 13C urea breath test in vivo. In this pilot study, we tried to replicate previous findings in an independent sample and to evaluate effects of spray-drying vs. freeze-drying of cultures. A single-blinded, placebo-controlled study was done in 22 H. pylori positive, asymptomatic adults. H. pylori levels were determined by 13C-urea-breath method after 14 days of supplementation, as well as after 6, 12, and 24 weeks follow-up. In the test group, but not in the placebo group, a significant reduction of H. pylori was observed. For the first time, spray-dried cells of L. reuteri DSMZ17648 have been used in a human study and results are in line with the first study results, supplementing with freeze-dried material. This is of special interest as spray-drying results in dead cell material, meaning that the effect of L. reuteri must be independent of its probiotic activity. These results confirm the potential of Pylopass™ as a novel way to reduce the load of H. pylori. © 2013 by the authors; licensee MDPI, Basel, Switzerland.
Schreiber A.,Experimental and Clinical Research Center |
Choi M.,Experimental and Clinical Research Center
Current Opinion in Hematology | Year: 2015
Purpose of review Antineutrophil cytoplasmic antibody (ANCA)-activated phagocytes cause vasculitis and necrotizing crescentic glomerulonephritis. Experimental data support the notion that activation of neutrophils and monocytes by ANCA immunoglobulin G with generation of reactive oxygen species, degranulation of proteases, and formation of neutrophil extracellular traps play a role in tissue injury. Recent findings We discuss novel findings regarding the expression of ANCA antigens and the mechanisms involved in myeloid cell activation by ANCA immunoglobulin G. The contribution of neutrophil serine proteases and their specific role in the generation of interleukin-1beta (IL-1β) is highlighted. ANCA-induced reactive oxygen species generation plays an important role in downregulating inflammation by inhibition of the inflammasome-dependent caspase-1 activation and subsequent IL-1β generation. Neutrophil extracellular trap generation by ANCA-activated neutrophils and their potential role in the pathogenesis of the disease will be discussed. Lastly, the pathogenic role of the complement system will be discussed. Summary ANCA-induced activation of both neutrophils and monocytes is one of the main pathogenic mechanisms involved in disease induction. Therefore, a better understanding of the fundamental processes involved here are necessary. Specifically, the mechanisms involved in IL-1β generation have been recently identified and could lead to better targeted novel therapies. © 2014 Wolters Kluwer Health | Lippincott Williams & Wilkins.
Herse F.,Experimental and Clinical Research Center |
Lamarca B.,University of Mississippi Medical Center
American Journal of Reproductive Immunology | Year: 2013
Autoantibodies can cause complications in pregnancy. Preeclampsia is the leading cause of maternal and fetal morbidity and mortality during pregnancy. Overall, 5-10% of all pregnancies worldwide develop preeclampsia. Women who developed preeclampsia and their children have an increased risk to suffer from cardiovascular diseases later in life. In preeclampsia, agonistic autoantibodies against the angiotensin II type 1 receptor autoantibodies (AT1-AA) are described. They induce NADPH oxidase and the MAPK/ERK pathway leading to NF-κB and tissue factor activation. AT1-AA are detectable in animal models of preeclampsia and are responsible for elevation of soluble fms-related tyrosine kinase-1 (sFlt1) and soluble endoglin (sEng), oxidative stress, and endothelin-1, all of which are enhanced in preeclamptic women. AT1-AA can be detected in pregnancies with abnormal uterine perfusion and increased resistance index as well as in patients with systemic sclerosis and renal allograft rejection. This review discusses the current knowledge about the AT1-AA, its signaling, and their impact in pregnancy complications and other autoimmune disorders. © 2012 John Wiley & Sons A/S.
Luft F.C.,Experimental and Clinical Research Center
Pflugers Archiv European Journal of Physiology | Year: 2015
Salt retention or salt deficit has a bearing on the body fluid volume. Both states are clinically difficult to recognize and quantitate. Salt deficit is particularly cumbersome in that regard since orthostatic blood pressure, heart rate changes, and simple physical inspection are inaccurate and unreliable. Salt deficit can be acute such as after hemorrhage or massive diarrhea, or more chronic as observed in Addison’s disease, failure of renal sodium chloride transporters, drug-related effects, or distal nephron disease. Molecular genetics has given us important new insights into salt deficit syndromes. Recent recognition of a novel sodium storage compartment involving sodium binding to proteoglycans adds to the overall complexity of these syndromes. © 2014, Springer-Verlag Berlin Heidelberg.
Tano J.-Y.,Experimental and Clinical Research Center |
Schleifenbaum J.,Experimental and Clinical Research Center |
Gollasch M.,Experimental and Clinical Research Center
Arteriosclerosis, Thrombosis, and Vascular Biology | Year: 2014
Perivascular adipose tissue has been recognized unequivocally as a major player in the pathology of metabolic and cardiovascular diseases. Through its production of adipokines and the release of other thus far unidentified factors, this recently discovered adipose tissue modulates vascular regulation and the myogenic response. After the discovery of its ability to diminish the vessel's response to vasoconstrictors, a new paradigm established adipose-derived relaxing factor (ADRF) as a paracrine smooth muscle cells' potassium channel opener that could potentially help combat vascular dysfunction. This review will discuss the role of ADRF in vascular dysfunction in obesity and hypertension, the different potassium channels that can be activated by this factor, and describes new pharmacological tools that can mimic the ADRF effect and thus can be beneficial against vascular dysfunction in cardiovascular disease. © 2014 American Heart Association, Inc.