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Les cellules musculaires lisses de l'artère pulmonaire (PA-PSM) peuvent contribuer à la pathogenèse de l'hypertension pulmonaire (PH) en produisant des facteurs sécrétés.Objectif: explorer le rôle de PH de protéines de la matrice extracellulaire libéré par Les cellules musculaires lisses de l'artère pulmonaire sénescentes (PA-PSM)Méthodes et résultats:L'analyse Microarray de l'ADN de PA-CML humaine subir à la sénescence réplicative révélé une régulation positive de l'ostéopontine, qui médie l'effet stimulateur ,du médium et de la matrice de l'AP-SMC de sénescentes, sur la croissance et de la migration des cellules musculaires lisses de l'artère pulmonaire. Osteopontin était régulé à la hausse dans les poumons de patients atteints de BPCO et de patients hypertension artérielle pulmonaire idiopathique (HAPi). Prominent ostéopontine immunocoloration a été noté dans le PA-SMC qui a également colorée pour p16 dans les sites de l'hypertrophie vasculaireet les niveaux de l'ostéopontine pulmonaire étalaient étroitement corrélée avec l'âge. Comparativement aux jeunes souris avec des souris ont 1 an affiche des niveaux plus élevés d'ostéopontine du poumon, et la pression systolique ventriculaire droite (de RVSP), et la muscularisation vasculaires pulmonaires, et le nombre de PA-CML colorée pour p16 ou p21 et aussi pour l'ostéopontine.Aucun de ces changements avec l'âge étaient observée dans les souris ostéopontine - / -, qui a développé atténués PH pendant l'hypoxie.Comparé de culture PA-CML, les PA-CML de souris ont 1 ans qui proliféraient plus rapide que PA-CML de jeunes souris. Avec un taux de croissance rapide a été observée avec PA-CML de jeunes souris stimulées par matrice ou médium issu de les PA-CML de souris âgées. Différences entre les anciens jeune souris / PA-SMC taux de croissance étaient supprimée par des anticorps anti-ostéopontine.culture de la PA-CML de souris ostéopontine - / - a augmenté de plus lente que fait chez PA-SMC de souris sauvage et ces cellules ont été stimulés par le medium et la matrice de PA-CML de type sauvage et cet effet était plus fort avec PA-CML de souris âgés par apport de souris jeunes.Conclusion: Osteopontin est un médiateur clé libéré par PA-SMC sénescente et contribuer à la progression de la HTAP. / Rationale: Senescent pulmonary artery smooth muscle cells (PA-SMCs) may contribute tothe pathogenesis of pulmonary hypertension (PH) by producing secreted factors.Objective: To explore the role in PH of extracellular matrix proteins released by senescentPA-SMCsMethods and results: Microarray analysis of human PA-SMCs undergoing replicativesenescence revealed osteopontin upregulation, which mediated the stimulatory effect ofsenescent PA-SMC media and matrix on PA-SMC growth and migration. Osteopontin wasupregulated in lungs from patients with COPD or idiopathic pulmonary arterial hypertension(PAH). Prominent osteopontin immunostaining was noted in PA-SMCs that also stained forp16 at sites of vascular hypertrophy, and lung osteopontin levels correlated closely with age.Compared to younger mice, 1-year-old mice displayed higher lung osteopontin levels, rightventricular systolic pressure (RVSP), pulmonary vessel muscularization, and numbers ofPA-SMCs stained for p16 or p21 and also for osteopontin. No such changes with age wereobserved in osteopontin-/- mice, which developed attenuated PH during hypoxia. Comparedto cultured PA-SMCs from young mice, PA-SMCs from 1-year-old mice grew faster; asimilar fast growth rate was seen with PA-SMCs from young mice stimulated by matrix ormedia from old mice. Differences between old/young mouse PA-SMC growth rates weresuppressed by anti-osteopontin antibodies. PA-SMCs from osteopontin-/- mice grew moreslowly than did wild-type PA-SMCs; they were stimulated by wild-type PA-SMCs mediaand matrix, and this effect was stronger with PA-SMCs from older vs. younger mice.Conclusion: Osteopontin is a key mediator released by senescent PA-SMCs andcontributing to PH progression.

Die Arbeit befasst sich mit dem Anschwellen von Neuronen und Gliazellen der Netzhaut, was einen wichtigen pathogenetischen Faktor des Netzhautödems darstellt. Osteopontin ist ein neuroprotektiver Faktor, der durch GDNF-Stimulation (glial cell line-derived neurotrophic factor) aus Müllerzellen ausgeschüttet wird. Die durch Osteopontin vermittelte Inhibition der osmotischen Zellschwellung von Müllerzellen der Ratte in Anwesenheit von Bariumionen oder H2O2 wird beschrieben und es wird dargestellt, dass Osteopontin keinen Einfluss auf die osmotische Zellschwellung der Bipolarzellen hat. Der für Müllerzellen beschriebene Effekt war dosisabhängig mit einer mittleren effektiven Konzentration von ca. 0,6 ng/ml. Durch den Einsatz pharmakologischer Rezeptor- oder Enzymblocker bzw. Antikörper werden die Schritte der Osteopontinwirkung identifiziert. Osteopontin induziert die Freisetzung von VEGF, Glutamat, ATP und Adenosin aus Müllerzellen. Die Osteopontinwirkung wurde verhindert durch die Blockade von spannungsabhängigen Natriumkanälen, T-Typ Calciumkanälen, Kalium- und Chloridkanälen. Der Effekt ist außerdem abhängig von einem intrazellulären Calciumsignal, der Aktivierung der Phospholipase C und der Proteinkinase C und der vesikulären Exozytose von Glutamat. Die Arbeit kommt zu dem Schluss, dass der neuroprotektive Effekt von Osteopontin teilweise durch das Verhindern eines Anschwellens der Müllerzellen und durch die Induktion einer Freisetzung von VEGF und Adenosin vermittelt wird.

Hintergrund: Über den Verlauf der Expression von Osteopontin (OPN) nach Tumorresektion ist bisher wenig bekannt. In dieser Studie bestimmten wir den zeitlichen Verlauf der OPN Plasmaspiegel vor und nach Operation. Methoden: Zwischen 2011 und 2013 wurden 41 Patienten mit HNO-Tumoren in einer prospektiven Studie erfasst (Gruppe A). Zu verschiedenen Zeitpunkten wurden Plasmaproben entnommen: T 0) vor, T1) am ersten postoperativen Tag, T2) eine Woche nach Operation und T3) vier Wochen nach Operation. Osteopontin und TGF β1 Plasmaspiegel wurden mit kommerziellen ELISA-Systemen bestimmt. Die Ergebnisse wurden mit 131 HNO-Tumorpatienten verglichen, von denen n=42 (Gruppe B1) primär bestrahlt, beziehungsweise n=89 (Gruppe B2) postoperativ bestrahlt wurden. Ergebnisse: Es zeigte sich ein signifikanter OPN Anstieg am ersten postoperativen Tag (T0 vs T1, p<0,01). OPN Plasmaspiegel sanken drei bis 4 Wochen nach der Operation zurück auf ihren Ausgangswert. OPN Plasmaspiegel waren positiv mit der postoperativen TGF β1 Expression korreliert, was ein Zusammenhang zu Wundheilungsprozessen vermuten lässt. Die Auswertung der Überlebenszahlen zeigte einen signifikanten Vorsprung für Patienten mit niedrigen OPN Plasmaspiegeln sowohl in der primär bestrahlten, als auch in der postoperativ bestrahlten Gruppe (B1: 33 vs 11,5 Monate, p>0,017, B2: Median nicht erreicht vs 33,4 Monate, p=0,031). TGF β1 war in Gruppe B1 ebenso prognostisch signifikant (33,0 vs 10,7 Monate, p=0,003). Schlussfolgerung: Patienten mit HNO-Tumoren zeigten einen Anstieg von Osteopontin Plasmaspiegeln unmittelbar nach Operation. Innerhalb der folgenden vier Wochen sinken die OPN Plasmaspiegel wieder auf ihr präoperatives Niveau. Der langanhaltende Anstieg hängt wahrscheinlich mit Wundheilprozessen zusammen. Die prätherapeutischen Plasmaspiegel von Osteopontin und TGF β1 hatten prognostische Aussagekraft. / Background: In head and neck cancer little is known about the kinetics of osteopontin (OPN) expression after tumor resection. In this study we evaluated the time course of OPN plasma levels before and after surgery. Methods: Between 2011 and 2013 41 consecutive head and neck cancer patients were enrolled in a prospective study (group A). At different time points plasma samples were collected: T0) before, T1) 1 day, T2) 1 week and T3) 4 weeks after surgery. Osteopontin and TGFβ1 plasma concentrations were measured with a commercial ELISA system. Data were compared to 131 head and neck cancer patients treated with primary (n=42) or postoperative radiotherapy (n=89; group B1 and B2). Results: A significant OPN increase was seen as early as 1 day after surgery (T0 to T1, p<0.01). OPN levels decreased to base line 3-4 weeks after surgery. OPN values were correlated with postoperative TGFβ1 expression suggesting a relation to wound healing. Survival analysis showed a significant benefit for patients with lower OPN levels both in the primary and postoperative radiotherapy group (B1: 33 vs 11.5 months, p=0.017, B2: median not reached vs 33.4, p=0.031). TGFβ1 was also of prognostic significance in group B1 (33.0 vs 10.7 months, p=0.003). Conclusions: Patients with head and neck cancer showed an increase in osteopontin plasma levels directly after surgery. Four weeks later OPN concentration decreased to pre-surgery levels. This long lasting increase was presumably associated to wound healing. Both pretherapeutic osteopontin and TGFβ1 had prognostic impact.

Endothelial Progenitor Cells (EPCs) are thought to participate in the healing of injured vascular endothelium by incorporating into the defect sites to mediate endothelial recovery. Recently, osteopontin (OPN) was shown to be fundamental in accelerating estrogen-dependent healing of injured blood vessels. Here, we are investigating the effect OPN has on EPC behavior. Late outgrowth human EPCs (LEPCs) were derived from circulating monocytes isolated by leukophoresis, and grown in culture until passage six. L-EPCs were then assayed for adhesion, spreading, chemotaxis, and haptotaxis, as well as resistance to detachment by flow electric cellsubstrate impedance sensing (ECIS). The results of standard and ECIS methods showed both dose and time dependent responses in cell adhesion and spreading. In addition, OPN promoted haptotactic migration of EPCs in Boyden chamber assays. LEPCs seeded onto 10μM OPN substrates and exposed to laminar flow had grater survival and higher resistance to detachment than OPN/static and flow only conditions. CD44 and !1 integrins were only responsible for approximately 50% of LEPCs adhesion to OPN compared to the unblocked condition. Western blots showed that Rho GTPases were activated in L-EPCs seeded on OPN. However, this activation could not be completely blocked by either CD44 or !1 integrin antagonists. These data confirm the direct effects of OPN on EPCs adhesion, and suggest that OPN works by mediating cell adhesion during vascular injury.

Endothelial Progenitor Cells (EPCs) are thought to participate in the healing of injured vascular endothelium by incorporating into the defect sites to mediate endothelial recovery. Recently, osteopontin (OPN) was shown to be fundamental in accelerating estrogen-dependent healing of injured blood vessels. Here, we are investigating the effect OPN has on EPC behavior. Late outgrowth human EPCs (LEPCs) were derived from circulating monocytes isolated by leukophoresis, and grown in culture until passage six. L-EPCs were then assayed for adhesion, spreading, chemotaxis, and haptotaxis, as well as resistance to detachment by flow electric cellsubstrate impedance sensing (ECIS). The results of standard and ECIS methods showed both dose and time dependent responses in cell adhesion and spreading. In addition, OPN promoted haptotactic migration of EPCs in Boyden chamber assays. LEPCs seeded onto 10μM OPN substrates and exposed to laminar flow had grater survival and higher resistance to detachment than OPN/static and flow only conditions. CD44 and !1 integrins were only responsible for approximately 50% of LEPCs adhesion to OPN compared to the unblocked condition. Western blots showed that Rho GTPases were activated in L-EPCs seeded on OPN. However, this activation could not be completely blocked by either CD44 or !1 integrin antagonists. These data confirm the direct effects of OPN on EPCs adhesion, and suggest that OPN works by mediating cell adhesion during vascular injury.

No description available.

Endothelial Progenitor Cells (EPCs) are thought to participate in the healing of injured vascular endothelium by incorporating into the defect sites to mediate endothelial recovery. Recently, osteopontin (OPN) was shown to be fundamental in accelerating estrogen-dependent healing of injured blood vessels. Here, we are investigating the effect OPN has on EPC behavior. Late outgrowth human EPCs (LEPCs) were derived from circulating monocytes isolated by leukophoresis, and grown in culture until passage six. L-EPCs were then assayed for adhesion, spreading, chemotaxis, and haptotaxis, as well as resistance to detachment by flow electric cellsubstrate impedance sensing (ECIS). The results of standard and ECIS methods showed both dose and time dependent responses in cell adhesion and spreading. In addition, OPN promoted haptotactic migration of EPCs in Boyden chamber assays. LEPCs seeded onto 10μM OPN substrates and exposed to laminar flow had grater survival and higher resistance to detachment than OPN/static and flow only conditions. CD44 and !1 integrins were only responsible for approximately 50% of LEPCs adhesion to OPN compared to the unblocked condition. Western blots showed that Rho GTPases were activated in L-EPCs seeded on OPN. However, this activation could not be completely blocked by either CD44 or !1 integrin antagonists. These data confirm the direct effects of OPN on EPCs adhesion, and suggest that OPN works by mediating cell adhesion during vascular injury.

Thesis (Ph. D.)--Rutgers University, 2007. / "Graduate Program in Microbiology and Molecular Genetics." Includes bibliographical references (p. 86-107).