Formation of functional collateral circulation, to repair blocked or damaged arterial blood flow, is an important process in amending adverse outcomes after acute coronary occlusion events. Inadequate capillary growth during pressure overloads impairs myocardial perfusion, often contributing to the progression of coronary heart disease and ischaemia. Considered to be the critical rate-limiting step in physiological angiogenesis, the binding of VEGF (vascular endothelial growth factor) to VEGFR (vascular endothelial growth factor receptors) is essential for the growth and repair of arteries. Conversely, VEGF mediated angiogenesis has also been shown to promote atherosclerosis through arterial wall thickening. However, an alternatively spliced soluble form of VEGFR-1 (sFlt-1) has been shown to inhibit VEGF activity. sFlt-1 binds and sequesters free extracellular VEGF and/or heterodimerizes with VEGFR preventing the angiogenic pathway occurring. As a result, the primary pathway of angiogenesis does not occur. In recent years this has led to debate over the nature of sFlt-1 in the VEGF system. However, the level of sFlt-1 found in cardiovascular disease (CVD) patients, as well as its stability in plasma, has allowed for current research into its involvement with ischemic disorders to take place. Enhanced T-cell activity that results in increased production of interferon-γ has been shown to have involvement in the pathogenesis of CVD. 7,8-dihydroneopterin (7,8 NP) production by monocytes and macrophages is primarily in response to stimulation by interferon-γ (IFN-γ) released by activated T-lymphocytes. When combined with neopterin, the oxidised product of 7,8 NP, the total neopterin is accounted for which is a measure of the total macrophage activation by interferon-γ. Therefore, the levels of total neopterin observed may reflect the level of cell-mediated immunity within individuals which could contribute to mortality post CVD event. Progression of coronary heart disease is often clinically silent, without signs or symptoms. For this reason, the ability of markers to monitor progression is a powerful tool for predicting cardiovascular risk and the level of preventative treatment required. This study shows, that in 514 stable post-ACS (MI or unstable angina) patients, above median baseline sFlt-1, total neopterin and 7,8 NP levels, were strong predictors of mortality over a median 5 year period. Furthermore, above median sFlt-1 levels were specifically predictive of CVD death (p=0.001). This suggests that sFlt-1, total neopterin and 7,8 NP may be useful markers for risk prediction in CVD patients, post-acute event, with potential to aid prognosis in previously diagnosed patients. In support of these findings, levels of sFlt-1 measured in plasma taken from patients, immediately prior to undergoing carotid endarterectomy procedures (n=27), were significantly raised in comparison to age and gender matched healthy controls (p<0.001). Furthermore, levels of sFlt-1 in patient and control groups were shown to be independent of both age and gender. Another aspect of the study, analysis of excised live plaque tissue from carotid endarterectomy patients, showed the presence of live inflammatory cell populations. Macrophages, in the plaque sections, could be stimulated in the presence of IFN-γ to produce significantly elevated (p<0.01) levels of the antioxidant 7,8 NP. Since bivariate analysis of 7,8 NP and sFlt-1, in plasma from the endarterectomy patients, yields a positive correlation (r=0.323, p<0.01), further analysis of live plaque may give insight into the association between inflammation and hypoxic up-regulation of sFlt-1. It is now generally accepted, in diseases with complex pathogenesis, that particular biomarkers are predominantly indicative of only a single variable in a wide range of contributing factors. The data generated in this study highlights the potential for sFlt-1, neopterin and 7,8 NP to be used as contributing biomarkers in the prognosis of patients suffering from CVD, which if confirmed, may have important clinical implications in the medical community.

ABSTRACT Preeclampsia (PE) is a one of the more common pregnancy complications that affects 5-8% of pregnancies worldwide and produces significant morbidity and mortality for mother and fetus. Shallow trophoblast invasion and insufficient maternal spiral artery remodeling early in gestation is believed to lead to a relatively hypoxic placenta with inflammatory and trophoblast endoplasmic reticulum (ER) stress. These stresses cause an imbalance in trophoblast expression of angiogenic/anti-angiogenic molecules with decreased placental growth factor (PGF) and increased soluble fms like tyrosine kinase-1 receptor (sFlt-1) production. The decrease in trophoblast PGF seems to be mediated at the transcriptional level while increased expression of sFlt-1 is mediated by alternative splicing. Two variants known to be elevated in PE are the sFlt-1i13 and sFlt-1e15a isoforms. Both share the first 13 exons of Flt-1. A read through into intron 13 and utilization of an alternative poly (A) signal sequence produces the sFlt-1i13 variants protein, while sFlt-1e15a results from alternative splicing of exon 14 to exon 15a, rather than exon 15, and utilization of an alternative poly (A) signal sequence. This angiogenic imbalance contributes to the clinical manifestations of PE later in pregnancy including maternal hypertension and proteinuria. Currently, there are no pharmacological options available for the prevention of PE and the only way to reverse PE symptoms is by delivery. The overall goal of my project was (1) to investigate potential therapeutic mechanisms that could be used to relieve the maternal symptoms of PE by correcting the angiogenic imbalance, and (2) to gain a better understanding of the alternative splicing mechanisms responsible for producing sFlt-1 gene expression in human trophoblast. PE shares some similar pathophysiology and risk factors with cardiovascular diseases. This has prompted use of statins as a potential therapy for PE. However, existing preclinical investigations for statin use has been mostly restricted to PE animal models without elucidating the cell types that respond to statin treatment. Therefore, we sought to determine the effect of statins on angiogenic gene expression in cells that are in direct contact with maternal blood during pregnancy and could contribute to PE: primary trophoblast and endothelial cells. Placental tissue and isolated cells were cultured under hypoxic stress (1% O2) as a model for the hypoxic environment noted in PE. We compared the effectiveness of two types of statins (hydrophilic vs hydrophobic) on angiogenic and anti-angiogenic gene expression from the human tissues and cells. Human placenta villus explants, umbilical vein endothelial cells (HUVECs), and cytotrophoblast were isolated from normal term placentae and cultured under low oxygen tension (1% O2) with serial concentrations of statins. Expression of proangiogenic genes (VEGF and PGF) and the prominent anti-angiogenic sFlt-1 isoforms (sFlt-1i13 & sFlt-1e15a) were analyzed. In villus explants, hypoxia (1% O2) tended to alter angiogenic gene expression in their predicted fashion, by increasing VEGF mRNA (hypoxia marker), decreasing PGF mRNA, and increasing both sFlt-1i13 and sFlt-1e15a mRNA expression. However, the changes in gene expression were quite variable and statistically not significant. Hypoxia significantly increased both sFlt-1i13 and sFlt-1e15a mRNA and protein expression in primary trophoblast but had limited effects on expression in HUVECs. Hypoxia significantly decreased PGF mRNA and protein expression in primary trophoblast, yet significantly increased PGF mRNA and protein expression in HUVECs. Concentrations of pravastatin or simvastatin used had limited effects on altering PGF mRNA and protein expression in any of the cell types. In primary trophoblast, lower concentrations of pravastatin (100/500 µg/ml) had no significant effects on sFlt-1i13 or sFlt-1e15a mRNA expression while higher concentrations (1000 µg/ml) significantly decreased sFlt-1i13 and tended to decrease sFlt-1e15a mRNA expression. Secreted sFlt-1 protein from trophoblast decreased with increasing concentrations of pravastatin. Similarly, simvastatin had limited effects and did not significantly decrease sFlt-1i13 or sFlt-1e15a expression in hypoxic primary trophoblast. Both pravastatin and simvastatin significantly down-regulated sFlt-1i13 and sFlt-1e15a mRNA expression and sFlt-1 protein production in HUVECs. To overcome the effects of statin treatments on sFlt-1 expression, primary HUVECs were treated with farnesyl pyrophosphate ammonium salt (FPP), an intermediate in the cholesterol synthesis pathway. FPP partially restored sFlt-1i13 and sFlt-1e15a mRNA expression. Our data support that the angiogenic imbalance seen in PE can be medicated by hypoxia, and that statin could be a promising medication to limit PE symptoms. The effect of statins may be more evident on endothelial cells than on trophoblast, and the reduction in sFlt-1 expression by statins seems to be partially mediated through the cholesterol synthesis pathway in endothelial cells. The antiangiogenic protein, sFlt-1, plays a central role in the pathophysiology of PE. Excessive amounts of the sFlt-1 receptor in maternal circulation leads to maternal endothelial cell dysfunction and subsequent clinical symptoms of PE. However, the mechanism governing sFlt-1 mRNA expression in trophoblast remains unclear. Jumonji C domain containing gene 6 (JMJD6) has been shown to be involved in splicing of sFlt-1i13 in endothelial cells, although with conflicting outcomes as to whether it increases or decreases alternative splicing of sFlt-1i13. It is unknown if JMJD6 functions to regulate splicing in human primary trophoblast. Therefore, we assessed whether JMJD6 expression is altered in primary trophoblast under hypoxia or ER stress and its ability to regulate alternative splicing of sFlt-1. Human cytotrophoblast were isolated from normal term placentae and were cultured in the presence or absence of ER stress inducer (tunicamycin) or at 1% O2 to simulate trophoblast stressors during PE. Expression of JMJD6, C/EBP homologous protein (CHOP), and sFlt-1 (sFlt-1i13, and sFlt-1e15a) variants were analyzed. Hypoxic stress significantly increases JMJD6, sFlt-1i13, and sFlt-1e15a mRNA expression. ER stress also tended to increase JMJD6, sFlt-1i13, and sFlt-1e15a mRNA expression in primary trophoblast. Collectively, our results show that low oxygen tension (1% O2) or ER stress increase JMJD6 mRNA expression which may contribute to increased sFlt-1i13 and sFlt-1e15a variant expression in primary trophoblast. Similarly, JMJD6 knock down with siRNA tends to slightly decrease sFlt-1i13 and sFlt-1e15a mRNA expression in primary trophoblast. JMJD6 overexpression in HTR-8 cells (choriocarcinoma) tended to increase sFlt-1i13 and sFlt-1e15a mRNA expression; however, results using HTR-8 were inconsistent due to extremely low expression of endogenous Flt-1 mRNA. To overcome this, a Flt-1 minigene plasmid was transfected into HTR-8 cell line. Under 1%O2 these cells increased expression of the sFlt-1i13 isoform. To more directly confirm effects of JMJD6 and hypoxia on sFlt-1 expression, HEK293 and JEG3 stable clones harboring the Flt-1 minigene were generated. Preliminary results from selected single colony isolates show that several stable clones express the Flt-1 minigene products. HEK293 and JEG3 stable clones harboring the Flt-1 minigene, HEK293-Flt1#5 and JEG3-Flt1#5 respectively, were cultured at 1%O2 for 48 or 72 hours. Hypoxic stress had no significant on altering sFlt-1 variant production or JMJD6 mRNA expression in HEK293-Flt1#5 cells. However, hypoxic JEG3-Flt1#5 cells significantly increased sFlt-1i13 isoform mRNA expression (˜6 fold) and mFlt-1 mRNA expression (2.5 Fold) and also increased JMJD6 mRNA expression (1.8 Fold). In summary, these data suggest a role for statins as a potential therapeutic approach for the prevention and treatment of PE by decreasing systemic sFlt-1 expression in endothelial cells. This effect seems most significant in endothelial cells. If substantiated by clinical studies, use of statins would offer an affordable and easily accessible therapy to lessen PE symptoms. Moreover, our preliminary data suggest a potential involvement of JMJD6 in splicing process of sFlt-1i13. Confirming of JMJD6 role in splicing of Flt-1 may provide therapeutic strategies to treat Flt-1 associated disorder.

The vascular endothelial growth factor (VEGF) family is prominently involved in angiogenesis, the formation of new vasculature. Overexpression has been linked to pathological conditions including solid tumor growth. Responses to VEGF are mediated by Flt-1 and KDR, two cell-surface receptors selectively expressed by vascular endothelial cells. A secreted form of Flt-1 (sFlt1) retains high affinity for VEGF and can compete for VEGF binding, thereby inhibiting angiogenic responses. In this study, a computational model of this ligand-receptor binding system is used to quantitatively describe the activation of KDR signaling by VEGF and its inhibition by sFlt-1. The model consists of a system of 12 ordinary differential equations, based on mass action kinetics, which describe, based on mass-action kinetics, the formation and disappearance of receptor-ligand complexes competent to transduce a VEGF signal. Cell-based assays were used to test predictions of the in silico model by measuring dynamics of 1) KDR tyrosine hosphorylation and 2) generation of intracellular second messengers in response to VEGF stimulation in the presence and absence of sFlt-1. Results indicate that the model predicts well the maximal activation in the presence of VEGF-A or the KDR-selective agonist VEGF-E. Subsequent characteristics of binding, such as time-to-peak activations, were less realistically modeled, suggesting that the mathematical descriptions of certain receptor fates (receptor internalization, sequestration or externalization) may need refinement. Also presented are the results of KDR activation experiments in the simultaneous presence of VEGF-A, sFlt1, and the Flt1-selective agonist placental growth factor (PlGF). Here, the model predicts accurately the percentage of inhibition of maximal activation when sFlt-1 is present in the system. Finally, a revised model that includes receptor heterodimerization is presented that suggests sFlt-1 can more effectively inhibit VEGF binding and activation when acting in a dominant negative fashion. Overall, the findings support the idea that the early events in VEGF signaling can be modeled successfully. A natural extension of the model, refined based on experimental testing, will be its application to normal physiological systems. / Ph. D.

Die Bedeutung der angiogenen Faktoren „soluble fms-like tyrosine kinase-1“ (sFlt-1) und „placental growth factor“ (PIGF) in der Pathogenese der Präeklampsie (PE) ist in den letzten Jahren hinreichend belegt worden. Bei Patienten mit manifester PE lassen sich dramatisch hohe sFlt-1- bzw. sehr niedrige PlGF-Werte nachweisen. Mittlerweile konnte in Studien die sFlt-1/PlGF-Ratio als sensitiver Parameter ermittelt werden. Ziel der vorliegenden Arbeit ist es, die Zusammenhänge zwischen klinischen Parametern der manifesten Präeklampsie und der sFlt-1/PlGF-Ratio zu spezifizieren. Dabei soll geprüft werden, ob bei manifester PE die Höhe der sFlt-1/PlGF-Ratio vor Entbindung klinische Bedeutung hat und mit Parametern des Schwangerschaftsausgangs in Beziehung steht.

Die Präeklampsie ist eine schwangerschaftsspezifische Erkrankung, deren klinische Zeichen in der Regel erst nach der 20. Schwangerschaftswoche auftreten. Behandlungsmöglichkeiten zur Verminderung von Komplikationen, wie der uterinen Wachstumsretardierung, sind durch ein spätes Erkennen des Krankheitsbildes limitiert. Ziel der Studie war es zu prüfen, ob die parallele Messung von uteriner Perfusion und der maternalen Blutplasmakonzentration der anti-/angiogenen Faktoren PlGF, sFlt-1 und sEndoglin im 2. Trimenon die prädiktive Wertigkeit der Dopplersonographie hinsichtlich der Entwicklung einer Präeklampsie erhöhen kann. Anhand der Ergebnisse weisen Frauen mit gestörter uteroplazentarer Perfusion und einem anschließend komplikationsreichen Verlauf erhöhte Werte an sFlt-1 und sEndoglin sowie erniedrigte Werte an PlGF im Vergleich zu Frauen mit normalem Schwangerschaftsausgang auf. Die zusätzliche Analyse dieser Faktoren konnte die prädiktive Fähigkeit der Dopplersonographie bezüglich einer Präeklampsie erhöhen, insbesondere bei der frühen Form mit Entbindung vor der 34. SSW. Somit können Hochrisikopatientinnen für die Entwicklung einer Präeklampsie durch die Messung von PlGF, sFlt-1 und sEndoglin frühzeitiger erfasst werden. Weitere Studien sind zur Bestimmung eines idealen Messungszeitpunktes, der optimalen Kombination der Faktoren und endgültiger Cutoffwerte notwendig.

Einleitung: Die Dysbalance proangiogener (Placental Growth Factor = PlGF) und antiangiogener Faktoren (soluble fms-like tyrosine kinase 1 = sFlt-1) gilt heute als pathophysiologische Grundlage bei der Entstehung einer Präeklampsie (PE), eines HELLP-Syndroms (Haemolysis, Elevated Liver enzymes, Low Platelets) oder einer intrauterinen Wachstumsretardierung (IUGR). Der sFlt1/PlGF-Quotient, ein sensitiver und robuster diagnostischer Marker, ist bereits Wochen vor der Krankheitsmanifestation erhöht. Ziel dieser Studie war es, die Wertigkeit des sFlt1/PlGFQuotienten als prädiktiven Faktor bei Risikopatientinnen zu untersuchen. Patienten und Methode: In diese prospektive Studie wurden 68 Patientinnen mit einer Einlingsschwangerschaft und mindestens einem Risikofaktor für das Auftreten einer PE, eines HELLP-Syndrom oder einer IUGR im Schwangerschaftsverlauf eingeschlossen. Die Patientinnen wurden je nach Verlauf der Schwangerschaft in eine Gruppe mit Symptomen (Fallgruppe) und eine Gruppe ohne Symptome (Kontrollgruppe) für eine der oben genannten Erkrankungen unterteilt. Der sFlt1/PlGF-Quotient wurde bei der Aufnahme in die Studie und im weiteren Schwangerschaftsverlauf bestimmt. Ergebnisse: Eine PE, ein HELLP-Syndrom oder eine IUGR trat bei 41 % der Risikopatientinnen auf. Der absolute Wert des sFlt-1/PlGF-Quotienten war nur bei der Gruppe mit Symptomen auf ≥ 85 erhöht und zeigte sich in der 25 + 0-31 + 0 SSW (p = 0,005) und ab der 35 + 0 SSW (p = 0,044) als prädiktiver Faktor für eine PE, ein HELLP-Syndrom oder eine IUGR. Ab 7–10 Wochen vor der Entbindung war, in der Fallgruppe stärker als in der Kontrollgruppe, ein Anstieg des sFlt1/PlGFQuotienten zu beobachten. Dieser war 0–2 Wochen vor der Entbindung bei beiden Gruppen (Kontrollgruppe (MW ± SA 66,9 ± 134) vs. Fallgruppe (MW ± SA 393,3 ± 147,4, p = 0,021) am stärksten und zeigte sich ebenfalls als prädiktiver Faktor für eine der genannten Schwangerschaftserkrankungen (p = 0,025). Schlussfolgerung: Bei Risikoschwangeren kann der sFlt1/PlGF-Quotient für die Einschätzung des individuellen Risikos für eine PE, ein HELLP-Syndrom oder eine IUGR im Schwangerschaftsverlauf genutzt werden. Wiederholte Messungen des Quotienten versprechen eine risikoangepasste Betreuung dieser Patientinnen.

Preeclampsia (PE) remains one of the most enigmatic and pervasive conditions developed during pregnancy and is a leading cause of maternal and fetal morbidity and mortality throughout the world. Afflicting nearly 5-8% of pregnancies in the Unites States, PE is most commonly characterized by an increase in blood pressure and high protein excretion near or after the 20th week of gestation. Unfortunately, few effective treatments are available, and the only "cure" is delivery. While the molecular pathogenesis of PE remains undefined, an interruption in placental blood flow, or placental ischemia, is widely observed as a primary contributor to the syndrome progression. Furthermore, to investigate the role of both pharmacological and non-pharmacological modalities to prevent placental ischemia induced hypertension, we employed a robust model of reduced utero-placental perfusion pressure (RUPP) in the pregnant rat. First, in Chapter IV, exercise initiated during gestation was not effective in the prevention of RUPP-induced hypertension, whereas exercise training prior to and continued through gestation prevented the increase in blood pressure. Though the molecular contributions to this effect are undefined, the effects appear to be independent of angiogenic balance restoration. Finally, in Chapter V, administration of 5-aminoimidazole-4-carboxamide-1-β-D-ribofuranoside (AICAR) was explored as a novel pharmacological modality to prevent the onset of hypertension and endothelial dysfunction in the RUPP model. As hypothesized, AICAR ameliorated the RUPP-induced hypertension, and the anti-hypertensive effect in the RUPP appears to be dependent on the restoration of angiogenic balance in the maternal plasma. This dissertation includes previously published and unpublished co-authored material.

Die Bedeutung der angiogenen Faktoren „soluble fms-like tyrosine kinase-1“ (sFlt-1) und „placental growth factor“ (PIGF) in der Pathogenese der Präeklampsie (PE) ist in den letzten Jahren hinreichend belegt worden. Bei Patienten mit manifester PE lassen sich dramatisch hohe sFlt-1- bzw. sehr niedrige PlGF-Werte nachweisen. Mittlerweile konnte in Studien die sFlt-1/PlGF-Ratio als sensitiver Parameter ermittelt werden. Ziel der vorliegenden Arbeit ist es, die Zusammenhänge zwischen klinischen Parametern der manifesten Präeklampsie und der sFlt-1/PlGF-Ratio zu spezifizieren. Dabei soll geprüft werden, ob bei manifester PE die Höhe der sFlt-1/PlGF-Ratio vor Entbindung klinische Bedeutung hat und mit Parametern des Schwangerschaftsausgangs in Beziehung steht.

Die Präeklampsie ist eine schwangerschaftsspezifische Erkrankung, deren klinische Zeichen in der Regel erst nach der 20. Schwangerschaftswoche auftreten. Behandlungsmöglichkeiten zur Verminderung von Komplikationen, wie der uterinen Wachstumsretardierung, sind durch ein spätes Erkennen des Krankheitsbildes limitiert. Ziel der Studie war es zu prüfen, ob die parallele Messung von uteriner Perfusion und der maternalen Blutplasmakonzentration der anti-/angiogenen Faktoren PlGF, sFlt-1 und sEndoglin im 2. Trimenon die prädiktive Wertigkeit der Dopplersonographie hinsichtlich der Entwicklung einer Präeklampsie erhöhen kann. Anhand der Ergebnisse weisen Frauen mit gestörter uteroplazentarer Perfusion und einem anschließend komplikationsreichen Verlauf erhöhte Werte an sFlt-1 und sEndoglin sowie erniedrigte Werte an PlGF im Vergleich zu Frauen mit normalem Schwangerschaftsausgang auf. Die zusätzliche Analyse dieser Faktoren konnte die prädiktive Fähigkeit der Dopplersonographie bezüglich einer Präeklampsie erhöhen, insbesondere bei der frühen Form mit Entbindung vor der 34. SSW. Somit können Hochrisikopatientinnen für die Entwicklung einer Präeklampsie durch die Messung von PlGF, sFlt-1 und sEndoglin frühzeitiger erfasst werden. Weitere Studien sind zur Bestimmung eines idealen Messungszeitpunktes, der optimalen Kombination der Faktoren und endgültiger Cutoffwerte notwendig.:Bibliographische Beschreibung Abkürzungsverzeichnis 1. Einleitung 1 2. Grundlagen 3 2.1 Anatomische und physiologische Grundlagen 3 2.1.1 Die menschliche Plazenta 3 2.1.2 Vaskuläre Veränderung während der Schwangerschaft 3 2.2 Hypertensive Schwangerschaftserkrankungen 4 2.3 Präeklampsie 8 2.3.1 Pathogenese 8 2.3.2 Erklärungsmodelle der Ätiologie 10 2.3.3 Aspekte zum 2-Phasenmodell 14 2.4 anti-/angiogene Faktoren PlGF, sFlt-1 und sEndoglin 15 2.4.1. Zusammenhang mit Präeklampsie 15 2.4.2 PlGF 15 2.4.3 sFlt-1 17 2.4.4 sEndoglin 19 2.5 Intrauterine Wachstumsretardierung 22 2.6 Dopplersonographie 23 3. Zielsetzung der Arbeit 24 4. Methoden und Material 25 4.1 Studiendesign 25 4.2 Patientinnengut 26 4.3 Dopplersonographie 27 4.3.1 Widerstandindizes zur Perfusionsdiagnostik uteroplazentarer Gefäße 27 4.3.2 Ultraschallgerät 29 4.3.3 Durchführung 29 4.4 ELISA 29 4.4.1 Allgemeine Funktionsweise 29 4.4.2 Probengewinnung 30 4.4.3 Materialliste 31 4.4.4 Durchführung 33 4.5 Statistik 35 5. Ergebnisse 37 5.1 Patientinnencharakteristika 37 5.2 Messung der anti-/angiogenen Faktoren 38 5.2.1. Messung von PlGF 38 5.2.2 Messung von sFlt-1 39 5.2.3. Messung von sEndoglin 40 5.2.4 Korrelation der einzelnen Parameter 41 5.2.5 Analyse der sFlt-1/PlGF-Ratio 43 5.3 Prädiktive Wertigkeit der anti-/angiogenen Faktoren 44 6. Diskussion 50 6.1 Analyse der gemessenen PlGF-, sFlt-1- und sEndoglinkonzentrationen 50 6.1.1 Analyse von PlGF 50 6.1.2 Analyse von sFlt-1 51 6.1.3 Analyse von sEndoglin 55 6.1.4 Korrelation und sFlt-1/PlGF-Ratio 56 6.2 Prädiktive Wertigkeit von Doppler und der anti-/angiogenen Faktoren PlGF, sFlt-1 und sEndoglin für die Entwicklung einer Präeklampsie 58 6.2.1. Analyse der prädiktiven Fähigkeit 58 6.2.2 Veränderungen der anti-/angiogenen Faktoren bei früher Präeklampsie 60 6.2.3 Veränderte Faktorenkonzentration als Hinweis auf PE oder IUGR? 61 6.2.4 Frühe Vorhersage der Präeklampsie 63 6.3 Klinischer Nutzen der Ergebnisse 65 7. Zusammenfassung der Arbeit 69 8. Literaturverzeichnis 72 9. Verzeichnis der Tabellen und Abbildungen 95 Publikation Danksagung

O lúpus eritematoso sistêmico (LES) é uma doença autoimune cuja fisiopatologia envolve mecanismos imunológicos, incluindo distúrbios nos processos de morte celular e nos mecanismos de eliminação de autoantígenos e de tolerância, acompanhados da formação de autoanticorpos patogênicos. Ele acomete principalmente mulheres jovens e a gestação nestas pacientes apresenta significativa morbimortalidade. Os achados clínicos e laboratoriais na nefrite lúpica são semelhantes àqueles encontrados em pacientes com pré-eclâmpsia (PE), especificamente hipertensão arterial, proteinúria e edema. Foi proposto o uso de fatores angiogênicos, como o fator de crescimento vascular endotelial (VEGF) e o fator de crescimento placentário (PlGF), e antiangiogênicos, como o receptor Fms-like tirosina quinase 1 solúvel (sFlt-1), para o diagnóstico diferencial entre estas duas condições, no entanto os dados disponíveis na literatura sobre estas citocinas em pacientes não gestantes com LES são inconsistentes. Este estudo foi desenhado para avaliar se existe diferença entre os níveis séricos de VEGF, PlGF e sFlt-1 em pacientes com LES com e sem atividade sistêmica da doença e se existe diferença nesses fatores quando comparamos pacientes com LES e mulheres saudáveis. Foram incluídas 54 mulheres com diagnóstico de LES em acompanhamento no ambulatório de Reumatologia do HUPE-UERJ, sem outra doença autoimune diagnosticada, e divididas de acordo com a atividade da doença. 30 pacientes tinham doença inativa (SLEDAI médio: 0,7) e 24 tinham doença ativa (SLEDAI médio: 11,6). 23 mulheres deste último grupo possuíam nefrite ativa, enquanto 20 das pacientes com doença em remissão já haviam apresentado nefrite ao longo da evolução do LES. O grupo controle foi formado por 34 mulheres hígidas atendidas no ambulatório de ginecologia da Policlínica Piquet Carneiro-UERJ. Considerando as três citocinas estudadas, as pacientes com LES apresentaram valores séricos médios superiores às mulheres do grupo controle (VEGF: 319,0 + 226,0 x 206,2 + 119,4, p=0,02; PlGF: 42,2 + 54,1 x 13,6 + 21,6, p=0,02; sFlt-1: 107,9 + 49,2 x 70,2 + 95,0, p=0,01). O grupo de pacientes com doença ativa também apresentou média superior ao controle nos três fatores (VEGF: 331,0 + 216,8 x 206,2 + 119,4, p=0,02; PlGF: 41,2 + 47,3 x 13,6 + 21,6, p=0,02; sFlt-1: 120,5 + 42,4 x 70,2 + 95,0, p=0,02), enquanto não foi encontrada diferença estatística entre o grupo de LES inativo e o controle. A média do sFlt-1 sérico foi maior nas pacientes com LES ativo do que a média das pacientes com a doença em remissão (120,5 + 54,9 x 97,8 + 42,4, p=0,02), mas não houve diferença significativa da média do VEGF e PlGF séricos entre os dois grupos. O melhor entendimento dos fatores angiogênicos e antiangiogênicos em pacientes com LES proporcionado por este estudo nos permite a análise dessas citocinas em gestantes com LES e, possivelmente, sua posterior aplicação como método diferencial entre nefrite lúpica e PE. / Systemic lupus erythematosus (SLE) is an autoimmune disease which pathophysiology involves immunological mechanisms including disturbances in the processes of cell death and mechanisms of elimination of autoantigens and tolerance, accompanied by formation of pathogenic autoantibodies. It mainly affects young women and pregnancy in these patients have significant morbidity and mortality. Clinical and laboratory findings in lupus nephritis are similar to those found in patients with preeclampsia (PE), specifically hypertension, proteinuria and edema. It has been proposed the use of angiogenic factors, such as vascular endothelial growth factor (VEGF) and placental growth factor (PlGF), and antiangiogenic factors, as soluble Fms-like tyrosine kinase-1 (sFlt-1), for the differential diagnosis between these two conditions, however available data in the literature about these cytokines in non-pregnant SLE patients are inconsistent. This study was designed to evaluate whether there are differences between serum levels of VEGF, PlGF and sFlt-1 in SLE patients with and without systemic disease activity and whether there are differences in these factors when comparing SLE patients with healthy women. 54 women with SLE followed at outpatient clinic of Rheumatology HUPE - UERJ were included. They had no other autoimmune disease diagnosed and were divided according to disease activity. 30 patients had inactive disease (mean SLEDAI: 0.7), and 24 had active disease (mean SLEDAI: 11.6). 23 women in this latter group had active nephritis, while 20 patients with inactive disease had history of lupus nephritis. The control group consisted of 34 healthy women who attended the Gynecology outpatient clinic at Policlínica Piquet Carneiro - UERJ. Considering the three studied cytokines, the SLE patients had higher mean serum levels than the control group (VEGF: 319.0 + 226.0 x 206.2 + 119.4, p=0.02; PlGF: 42.2 + 54.1 x 13.6 + 21.6, p=0.02; sFlt-1: 107.9 + 49.2 x 70.2 + 95.0, p=0.01). The group of patients with active disease also had higher mean levels of all three factors than controls (VEGF: 331.0 + 216.8 x 206.2 + 119.4, p=0.02; PlGF: 41.2 + 47.3 x 13.6 + 21.6, p=0.02; sFlt-1: 120.5 + 42.4 x 70.2 + 95.0, p=0.02), whereas no statistical difference was found between the group with inactive SLE and the control group. The mean sFlt-1 levels were higher in patients with active SLE than the mean levels of patients with inactive disease (120.5 + 54.9 x 97.8 + 42.4, p=0.02), but there was no significant difference in mean serum of VEGF and PlGF levels between these two groups. A better understanding of angiogenic and antiangiogenic factors in patients with SLE provided by this study allows the analysis of these cytokines in pregnant woman with SLE and possibly their subsequent application as differential method between PE and lupus nephritis.