High levels of lactate are positively associated with the prognosis and mortality in patients with heart attack. Endothelial-to-mesenchymal transition (EndoMT) plays an important role in cardiac fibrosis. Here, we report that lactate exerts a previously unknown function that increases cardiac fibrosis and exacerbates cardiac dysfunction by promoting EndoMT following myocardial infarction (MI). Treatment of endothelial cells with lactate disrupts endothelial cell function and induces mesenchymal-like function following hypoxia by activating the TGF-β/Smad2 pathway. Mechanistically, lactate induces an association between CBP/p300 and Snail1, leading to lactylation of Snail1, a TGF-β transcription factor, through lactate transporter monocarboxylate transporter (MCT)-dependent signaling. Inhibiting Snail1 diminishes lactate-induced EndoMT and TGF-β/Smad2 activation after hypoxia/MI. The MCT inhibitor CHC mitigates lactate-induced EndoMT and Snail1 lactylation. Silence of MCT1 compromises lactate-promoted cardiac dysfunction and EndoMT after MI. We conclude that lactate acts as an important molecule that up-regulates cardiac EndoMT after MI via induction of Snail1 lactylation.

no / This study aimed at determining the role of the transforming growth factor-beta (TGF-β) isomers and their combinations in bone cell behaviour using MG63 cells. The work examined how TGF-β1, 2 and 3 and their solvent and carrier (HCl and BSA, respectively) effected cell morphology, cell proliferation and integrin expression. This study also aimed at examining how the TGF-βs and their solvent and carrier influenced wound closure in an in vitro wound closure model and how TGF-βs influence extracellular matrix (ECM) secretion and integrin expression. The wound healing response in terms of healing rate to the TGF-βs and their solvent/carrier was investigated in 300 μm ± 10–30 μm SD wide model wounds induced in fully confluent monolayers of MG63 bone cells. The effect of different TGF-β isomers and their combinations on proliferation rate and cell length of human bone cells were also assessed. Immunostaining was used to determine if TGF-βs modifies integrin expression and ECM secretion by the bone cells. Imaging with WSPR allowed observation of the focal contacts without the need for immunostaining. The wound healing results indicated that TGF-β3 has a significant effect on the wound healing process and its healing rate was found to be higher than the control (p < 0.001), TGF-β1 (p < 0.001), TGF-β2 (p < 0.001), BSA/HCl (p < 0.001) and HCl (p < 0.001) in ascending order. It was also found that TGF-β1 and TGF-β2 treatment significantly improved wound closure rate in comparison to the controls (p < 0.001). All TGF-β combinations induced a faster healing rate than the control (p < 0.001). It was expected that the healing rate following treatment with TGF-β combinations would be greater than those healing rates following treatments with TGF-β isomers alone, but this was not the case. The results also suggest that cell morphological changes were observed significantly more in cells treated with TGF-β(2 + 3) and TGF-β(1 + 3) (p < 0.001). Any cell treated with TGF-β1, TGF-β(1 + 2) and TGF-β(1 + 2 + 3) showed significantly less elongation compared to the control and other TGF-β isomers. In terms of proliferation rate, TGF-β3 and TGF-β(2 + 3) increased cell numbers more than TGF-β1, TGF-β2 and other combinations. TGF-β1 and its combinations did not show significant proliferation and attachment compared to the control. Immunostaining indicated that treatment with TGF-β3 significantly enhanced the secretion of collagen type I, fibronectin and integrins α3 and β1. The WSPR experiments also indicated that TGF-βs influenced the distribution of focal contacts. In conclusion, combining TGF-β3 with any other TGF-β isomer resulted in a faster model wound closure rate (p < 0.001), while treatment with TGF-β1 in any TGF-β combination reduced the healing rate (p < 0.001). It can therefore be concluded that the presence of TGF-β1 has an inhibitory effect on bone wound healing while TGF-β3 had the opposite effect and increased the rate of wound closure in a 2 dimensional cell culture environment. / Emailed Mansour for final draft 27/06/2016

Osteoarthritis (OA) ist eine chronische Erkrankung der Gelenke des menschlichen Körpers, insbesondere des Kniegelenkes. Sie ist durch entzündliche und degenerative Prozesse gekennzeichnet, die Patienten in ihrer Beweglichkeit stark einschränkt. In der komplexen Pathophysiologie kommt es unter anderem zu zellmorphologischen Veränderungen der knorpelbildenden Zellen, den Chondrozyten, und zu destruktiven Veränderungen der Knorpelmatrix. Bisherige therapeutische Ansätze bestehen in meist in einer rein symptomatischen Therapie durch Schmerzmittel sowie der operativen endoprothetischen Versorgung als Ultima Ratio. Eine kurative Therapie ist bisher nicht möglich. Einen Ansatz für eine kurative Therapie könnte eine Subpopulation der Zellen des Knorpelgewebes bieten. Chondrogene Progenitor Zellen (CPCs) stellen als Vorläuferzellen der Chondrozyten, gesteuert durch das prochondrogene Gen SOX9 und das proosteogene Gen RUNX2, einen möglichen regenerativen Ansatz in der Behandlung dar. Eine Rolle in diesem Prozess könnten die Wachstumsfaktoren TGF- β3 und EGF sowie das Matrixmolekül Biglycan darstellen. In dieser Arbeit konnte gezeigt werden, dass diese Wachstumsfaktoren, deren Rezeptoren und das Matrixmolekül Biglycan im osteoarthrischen Knorpel eine Rolle spielen. Insbesondere konnte in vitro gezeigt werden, dass CPCs unter dem Einfluss dieser Moleküle zu einer vermehrten SOX9 und verminderten RUNX2-Expression angeregt werden. Unter der Hypothese, dass sich CPCs auf diese Art zu Chondrozyten differenzieren lassen und so den Knorpel wiederherstellen, könnten diese Moleküle einen möglichen Baustein einer zukünftigen Therapie der OA darstellen.

Diss. (sammanfattning) Linköping : Linköpings universitet, 2008. / Härtill 4 uppsatser.

Thesis (Ph.D. in Pharmacology) -- University of Colorado Denver, 2007. / Typescript. Non-Latin script record Includes bibliographical references (leaves 112-128). Free to UCD affiliates. Online version available via ProQuest Digital Dissertations;

Die Knochenhomöostase erfolgt durch das Zusammenspiel mehrerer Zelltypen. Während die Osteoblasten für den Knochenaufbau verantwortlich sind, resorbieren die Osteoklasten Knochengewebe. Beide Vorgänge werden durch die Osteozyten streng reguliert. Eine Störung im strikt regulierten Gleichgewicht zwischen Knochenabbau und Knochenaufbau kann daher zu Knochenkrankheiten wie Osteoporose führen. Auf molekularer Ebene erfolgt die Kommunikation zwischen den einzelnen Zelltypen über zwei wichtige Signalwege, den der „Bone Morphogenetic Protein“-Superfamilie (BMPs) und den der Wnt-Proteine. Die Signalübertragung wird hierbei durch sekretierte Faktoren induziert, die an Rezeptoren auf der Zelloberfläche binden. Deren Aktivierung führt zu einem intrazellulären Signal, welches letztlich die Expression von Zielgenen reguliert. Beide Signalwege werden auf mehreren Ebenen, extrazellulär, membranständig und intrazellulär reguliert. Das 2003 identifizierte Sclerostin ist ein Vertreter der extrazellulären Regulatorproteine und wurde aufgrund seiner Zugehörigkeit zur DAN-Familie zunächst fälschlicherweise als direkter Inhibitor des BMP-Signalwegs eingestuft. Mittlerweile wird allerdings davon ausgegangen, dass Sclerostin den Wnt-Signalweg negativ reguliert, indem es die Wnt Ko-Rezeptoren LRP5 und LRP6 bindet, die beide zu der Familie der „Low-density lipoprotein receptors“ gehören. Über den molekularen Inhibitionsmechanismus von Sclerostin war jedoch zum Startpunkt dieser Dissertationsarbeit wenig bekannt. Daher wurde Sclerostin im Rahmen dieser Arbeit biophysikalisch und biochemisch charakterisiert. Die Aufklärung mittels NMR-Spektroskopie ergab für Sclerostin eine Struktur, die sich in drei Regionen gliedert: den Cystinknoten, sowie einen „Loop“-Bereich und die Fingerregion. Vom zentralen Cystinknoten gehen drei Peptid-Schleifen in zwei entgegengesetzte Richtungen aus. Schleife eins und drei bilden eine definierte ß-Faltblattstruktur und ähneln zwei Fingern einer Hand. Die zweite Schleife, welche vom Cystinknoten isoliert in die entgegengesetzte Richtung verläuft („Loop“), ist wie die beiden langen N- und C-Termini flexibel und unstrukturiert. Die in Zusammenarbeit mit der Firma AbD-Serotec entstandenen Fab-Fragmente ermöglichten die Bestimmung des Bindeepitops der Sclerostin/LRP5-Interaktion im Bereich der unstrukturierten dritten Schleife von Sclerostin. Die Struktur von Sclerostin und die Identifikation des Bindeepitops auf Sclerostinseite geben nun erste Einblicke in den molekularen Mechanismus der Sclerostin/LRP5-Interaktion. Diese Kenntnis kann für die Entwicklung von Kleinmolekülinhibitoren mittels rationalem Drugdesign genutzt werden, welche, wie auch der in Kooperation entwickelte die Sclerostinaktivität neutralisierende Antikörper AbD09097, hochinteressante Ansätze für neuartige anabole Therapien von Krankheiten mit Knochenschwund darstellen. / Different cell types like osteoblasts, osteoclasts and osteocytes maintain bone homeostasis. While osteoblasts build up bone, osteoclasts resorb bone tissue and both actions are tightly regulated by the osteocytes. Imbalance between bone formation and resorption will lead to various bone diseases, e.g. osteoporosis. On a molecular level communication between these cell types occurs through two major signalling pathways, i.e. the bone morphogenetic proteins (BMPs) and the Wnt-factors. In both pathways signal transduction is induced by secreted factors, which bind to cell surface receptors. This activation leads to an intracellular signal that finally regulates expression of target genes. Both pathways are tightly regulated at various cellular levels, extracellular, at the membrane as well as intracellular. Sclerostin, which was identified in 2003, is a member of the extracellular modulator proteins. Initially it was wrongly classified as a direct inhibitor of the BMP-signalling pathway due to its classification as a member of the DAN-family. Meanwhile it became apparent that sclerostin targets the Wnt-pathway by binding to the Wnt co-receptors LRP5 and LRP6, which belong to the family of low-density lipoprotein receptors. At the beginning of this work very little was known about the molecular mechanism how sclerostin inhibits the Wnt-pathway. The structure analysis of sclerostin employing NMR-spectroscopy revealed in a modular architecture, which can be divided into three regions: the central, characteristic cystine knot, the loop-region and the two fingers. From the cystine knot three loops emanate in two opposite directions. Loop one and loop three form defined ß-sheet structures resembling two fingers of a hand. Loop two, which runs into the opposite direction, is unstructured and highly flexible like the long N- and C-termini. Antibody fab-fragments, which were generated in collaboration with AbD-Serotec, facilitated the mapping of the binding-epitop of sclerostin to LRP5/6, highlighting an extended area of the unstructured loop region of sclerostin as the LRP5/6 binding site. The high-resolution structure of sclerostin and the identification of the LRP5-binding-epitop yield first insights into the molecular mechanism of sclerostin-LRP5 interaction. This knowledge can now be used to develop small-molecule inhibitors by rational drug design, which are, like the sclerostin activity neutralising fab-fragment AbD09097, highly interesting targets for new bone-anabolic therapies of diseases characterised by bone loss.

Bone Morphogenetic Proteins (BMPs) are secreted multifunctional signaling proteins that play an important role during development, maintenance and regeneration of tissues and organs in almost all vertebrates and invertebrates. BMPs transmit their signals by binding to two types of serine-/threonine-kinase receptors. BMPs bind first to their high affinity receptor, thereby recruiting their low affinity receptor into the complex. This receptor assembly starts a Smad (Small mothers against decapentaplegic) protein signaling cascade which regulates the transcription of responsive genes. Up to date, only seven type I and five type II receptors are known for more than 30 ligands. Therefore, many BMP ligands can recruit more than one receptor subtype. Vice versa, receptors can bind to several ligands, indicating a highly promiscuous ligand-receptor interaction. This raises the following questions: (i) How are BMPs able to induce ligand-specific signals, despite forming complexes with identical receptor composition and (ii) how are they able to recognize and bind various binding partners in a highly specific manner. From the ligand’s point of view, heterodimeric BMPs are valuable tools for studying the interplay between different sets of receptors, thereby providing new insights into how the various BMP signals can be generated. This study describes the expression and purification of the heterodimers BMP-2/6 and -2/7 from E.coli cells. BIAcore interaction studies and various in vitro cell activity assays revealed that the generated heterodimers are biologically active. Furthermore, BMP-2/6 and -2/7 exhibit a higher biological activity in most of the cell assays compared to their homodimeric counterparts. In addition, the BMP type I receptor BMPR-IA is involved in heterodimeric BMP signaling. However, the usage of other type I receptor subtypes (e.g. ActR-I) building a heteromeric ligand-receptor type I complex as indicated in previous works could not be determined conclusively. Furthermore, BMP heterodimers seem to require only one type I receptor for signaling. From the receptors’ point of view, the BMP type I receptor BMPR-IA is a prime example for its promiscuous binding to different BMP ligands. The extracellular binding interface of BMPR-IA is mainly unfolded in its unbound form, requiring a large induced fit to adopt the conformation when bound to its ligand BMP-2. In order to unravel whether the binding promiscuity of BMPR-IA is linked to structural plasticity of its binding interface, the interaction of BMPR-IA bound to an antibody Fab fragment was investigated. The Fab fragment was selected because of its ability to recognize the BMP-2 binding epitope on BMPR-IA, thus neutralizing the BMP-2 mediated receptor activation. This study describes the crystal structure of the complex of the extracellular domain of BMPR-IA bound to the antibody Fab fragment AbyD1556. The crystal structure revealed that the contact surface of BMPR-IA overlaps extensively with the contact surface of BMPR-IA for BMP-2 interaction. Although the contact epitopes of BMPR-IA to both binding partners coincide, the three-dimensional structures of BMPR-IA in both complexes differ significantly. In contrast to the structural differences, alanine-scanning mutagenesis of BMPR-IA showed that the functional determinants for binding to both the antibody and BMP-2 are almost identical. Comparing the structures of BMPR-IA bound to BMP-2 or to the Fab AbyD1556 with the structure of unbound BMPR-IA revealed that binding of BMPR-IA to its interaction partners follows a selection fit mechanism, possibly indicating that the ligand promiscuity of BMPR-IA is inherently encoded by structural adaptability. / „Bone Morphogenetic Proteins” (BMPs) sind sezernierte multifunktionelle Signalproteine, die eine wichtige Rolle während der Entwicklung, Aufrechterhaltung und Regeneration von Geweben und Organen in fast allen Vertebraten und wirbellosen Tieren spielen. Die BMP-Signalgebung wird durch die Bindung an zwei Typen von Serin/Threonin Rezeptorkinasen eingeleitet. Hierbei binden BMPs zuerst an ihren hochaffinen Rezeptor, bevor der niederaffine Rezeptor in den Komplex eingefügt wird. Durch das Zusammenfügen beider Rezeptortypen wird eine von Smad (Small mothers against decapentaplegic)-Proteinen gesteuerte Signalkaskade gestartet, die letztendlich die Transkription responsiver Gene reguliert. Aktuell sind nur sieben Typ I und fünf Typ II Rezeptoren für mehr als 30 Liganden bekannt. Viele BMP-Liganden können demzufolge mehr als einen Rezeptorsubtyp rekrutieren. Umgekehrt jedoch können auch Rezeptoren an unterschiedliche Liganden binden, was auf eine im hohen Maße promiske Ligand-Rezeptor-Interaktion hinweist. Dabei stellen sich folgende Fragen: (i) Wie können BMPs ligandspezifische Signale erzeugen, obwohl sie dafür die gleichen Rezeptoren benutzen? (ii) Und wie können BMPs unterschiedliche Bindungspartner erkennen und trotzdem hochspezifisch an diese binden? Von Blickwinkel der Liganden aus betrachtet stellen heterodimere BMPs wertvolle Hilfsmittel dar, um das Zusammenspiel zwischen den verschiedenen Rezeptortypen zu studieren. Darüber hinaus können sie neue Einblicke in die Entstehung von unterschiedlichen BMP-Signalen gewähren. In dieser Doktorarbeit wird die Expression und Aufreinigung von heterodimeren BMP-2/6 und -2/7 aus E.coli Zellen beschrieben. Mittels BIAcore Interaktionsstudien und in vitro Aktivitätsassays in Säugerzellen konnte gezeigt werden, dass die hergestellten Heterodimere biologisch aktiv sind. Darüber hinaus zeigen BMP-2/6 and -2/7 in den meisten Zellassays eine höhere biologische Aktivität als ihre homodimeren Gegenstücke. Außerdem konnte nachgewiesen werden, dass der BMP Typ I Rezeptor BMPR-IA an der Signalgebung von heterodimeren BMPs involviert ist. Eine Beteiligung weiterer Typ I Rezeptoren (wie z.B. die von ActR-I), die einen heteromeren Ligand-Rezeptor Typ I Signalkomplex bilden, wie es bereits in früheren Studien gezeigt wurde, konnte jedoch experimentell nicht eindeutig belegt werden. Des Weiteren lassen die Ergebnisse darauf schließen, dass heterodimere BMPs für eine erfolgreiche Signalweiterleitung nur die Präsenz eines einzelnen Typ I Rezeptors benötigen. Von Blickwinkel der Rezeptoren aus betrachtet, ist der BMP Typ I Rezeptor BMPR-IA ein Paradebeispiel für promiskes Bindeverhalten an verschiedene BMP-Liganden. Das extra-zelluläre Kontaktepitop von BMPR-IA ist im Wesentlichen ungefaltet, wenn BMPR-IA in freier ungebundener Form vorliegt. Infolge dessen durchläuft die Binderegion in BMPR-IA weit reichende strukturelle Veränderungen, um die erforderliche Konformation auszubilden, die für die Bindung an BMP-2 essentiell ist. Um herauszufinden, ob das promiske Binde-verhalten von BMPR-IA mit einer strukturellen Plastizität seiner Binderegion einhergeht, wurde die Interaktion zwischen BMPR-IA und einem Antikörper Fab Fragment experimentell untersucht. Das Fab Fragment wurde aufgrund folgender Eigenschaft ausgewählt, nämlich an das BMP-2 Bindeepitop des Rezeptors anzudocken, um so eine BMP-2 vermittelte Rezeptoraktivierung zu verhindern. In dieser Doktorarbeit wird die Kristallstruktur des Komplexes, bestehend aus der extrazellulären Domäne von BMPR-IA und dem Antikörper Fab Fragment AbyD1556 beschrieben. Die Kristallstruktur zeigt, dass die Kontaktoberfläche von BMPR-IA zu einem sehr großen Teil mit der Kontaktoberfläche bei der Interaktion mit BMP-2 übereinstimmt. Obwohl das Kontaktepitop von BMPR-IA zu beiden Bindungspartnern weitestgehend deckungsgleich ist, unterscheiden sich die dreidimensionalen Strukturen von BMPR-IA in beiden Komplexen sehr stark voneinander. Im Gegensatz zu den strukturellen Differenzen zeigt jedoch eine Mutationsanalyse, bei der wichtige Aminosäuren mit Alanin ausgetauscht wurden, dass die funktionellen Determinanten, die die Bindung an den Antikörper und an BMP-2 bestimmen, beinahe die gleichen sind. Wenn man die Strukturen von BMPR-IA, das an BMP-2 bzw. an das Fab Fragment AbyD1556 gebunden ist, mit der Struktur von ungebundenem BMPR-IA vergleicht, so fällt auf, dass die Bindung von BMPR-IA an seine Bindungspartner einem sog. „Selektions-Anpassungsmechanismus“ folgt, was möglicherweise zeigt, dass das promiske Ligand-Bindeverhalten von BMPR-IA von Natur aus durch seine strukturelle Anpassungsfähigkeit festgelegt wird.

目的： 转化生长因子－1（TGF-β1）通过与II型受体结合而引起I型受体活化，进一步激活其下游信号分子蛋白Smad2 和Smad3，它们与Smad4（Co-Smad）结合后形成Smad复合体并发生核转移，从而发挥广泛的生物学效应。同时，整个TGF-β信号通路又受到其抑制因子Smad7的负反馈调节。研究结果显示Smad3是肾脏炎症和纤维化中重要的致病分子，相反，Smad7在多种肾脏疾病中起保护作用。然而，由于转化生长因子II型受体（TβRII），Smad2 或Smad4基因敲除的小鼠无法存活，这些分子在TGF-β1介导的肾脏炎症和纤维化中的功能尚未见报道。因此，本研究旨在剖析TβRII、Smad2 和Smad4 在肾脏疾病发生发展中的作用及机制。 / 方法：本研究利用Cre/LoxP系统分别靶向敲除小鼠肾小管上皮细胞的TβRII、Smad2 或者Smad4，通过结扎小鼠单侧输尿管建立梗阻性肾病模型，观察这些分子对肾脏炎症和纤维化的影响，并用体外实验进行验证。具体实验结果请参见本论文第III,IV, V章。 / 结果：通过分析，本论文取得以下新的发现： / (1) TβRII在TGF-β1介导的肾脏炎症和纤维化的双向调节中起到了决定性的作用：研究结果显示条件性敲除TβRII明显抑制TGF-β/Smad3介导的肾脏纤维化，同时增强NF-κB引起的肾脏炎症反应。由此可见，TRII不仅仅是TGF-β/Smad信号通路的启动因子，更决定了TGF-β1对肾脏炎症和纤维化的双向性调节。(参见第III章) / (2)尽管Smad2和Smad3结构相似并共同介导了TGF-β1的生物学效应，本研究意外发现Smad2可反向调节Smad3引起的纤维化。体内和体外实验共同证实，敲除Smad2基因增强了Smad3的磷酸化，核转位及其转录子活性，并能促进Smad3与I型胶原转录子的结合，进而加重肾脏纤维化（参见第IV章）。 / (3)我们还发现Smad4不仅作为TGF-β/Smad信号通路的共有蛋白，它在TGF-β1介导肾脏炎症和纤维化中起到了重要的双向性调节作用：条件敲除Smad4显著降低了Smad7对NF-κB介导肾脏炎症的抑制作用，同时在转录水平（而非磷酸化水平）抑制Smad3的功能，从而减轻纤维化。（参见第V章） / 结论：TβRII和Smad4 在TGF-β1介导肾脏炎症和纤维化中起到了重要的双向性作用；Smad2通过抑制Smad3信号传导和功能，在肾脏纤维化中起保护作用。 / Objectives: TGF-β1 binds its receptor II (TβRII) and then activates receptor I to initiate the downstream Smad signaling, called Smad2 and Smad3 which bind a common Smad4 to form the Smad complex and then translocate to nucleus to exert its biological activities. This process is negatively regulated by an inhibitory Smad7. While the pathogenic role of Smad3 and the protective role of Smad7 in renal fibrosis and inflammation are clearly understood, the functional role of TβRII, Smad2 and Smad4 in kidney diseases remains largely unexplored due to the lethality of these knockout mice. Therefore, the aim of present study is to dissect the functional role of these TGF-β/Smad signaling molecules in renal inflammation and fibrosis. / Methods: Kidney conditional knockout (KO) mice for TβRII, Smad2 and Smad4 were generated by crossing the FloxFlox mice with the kidney specific promoter driven Cre (KspCre) mice, in which TβRII, Smad2 or Smad4 were specifically deleted from the kidney tubular epithelial cells (TEC) respectively. Then, a well-characterized progressive renal inflammation and fibrosis mouse model of Unilateral ureteral obstructive (UUO) nephropathy was induced in these conditional KO mice and the specific roles for TβRII, Smad2, and Smad4 in renal inflammation and fibrosis were investigated in vivo and in vitro as described in the Chapter III, IV and V of this thesis. / Results: There were several novel findings through this thesis: / 1. TGF-β1 signals through its TβRII to diversely regulate renal fibrosis and inflammation. We found that disrupted TRII suppressed Smad3-dependent renal fibrosis while enhancing NF-κB-driven renal inflammation. Thus, TβRII not only acts as a binding receptor for initiating the TGF-β signaling, but also determines the diverse role of TGF-β1 in inflammation and fibrosis, which was described in the Chapter III. / 2. As shown in the Chapter IV, an unexpected finding from this thesis was that although Smad2 and Smad3 were homologically similar and bound together in response to TGF-β1 stimulation, Smad2 counter-regulated Smad3-mediated renal fibrosis. This was evidenced by the findings that conditional deletion of Smad2 enhanced Smad3 signaling including phosphorylation, nuclear translocation, the Smad3 responsive promoter activity, and the binding of Smad3 to Col1A2 promoter. Thus, disrupted Smad2 from the kidney significantly enhanced Smad3-mediated renal fibrosis in the UUO kidney and in cultured TEC. / 3. Finally, we also showed that that Smad4 acted not only as a common Smad in TGF-β signaling, but exerted its regulatory role in determining the diverse role of TGF-β1 in renal inflammation and fibrosis. Disruption of Smad4 significantly enhanced renal inflammation by impairing inhibitory effect of Smad7 on NF-κB-driven renal inflammation. In contrast, disrupted Smad4 inhibited renal fibrosis by blocking Smad3 functional activity without influencing Smad3 signaling. Because deletion of Smad4 inhibited TGF-β1-induced Smad3 responsive promoter activity and the binding of Smad3 to the Col1A2 promoter without altering the phosphorylation and nuclear translocation of Smad3 (Chapter V). / Conclusions: TβRII and Smad4 may function as key regulators of TGF-β signaling and diversely regulate the renal inflammation and fibrosis. Smad2 plays a protective role in renal fibrosis by counter-regulating Smad3 signaling. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Meng, Xiaoming. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 202-231). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese. / Abstract --- p.i / Declaration --- p.viii / Acknowledgement --- p.ix / Table of Contents --- p.xii / List of Abbreviations --- p.xxvii / List of Figures/Tables --- p.xxix / Chapter CHAPTER I --- INTRODUCTION --- p.1 / Chapter 1.1 --- TGF-β signaling pathway --- p.2 / Chapter 1.1.1 --- TGF-β superfamily --- p.2 / Chapter 1.1.2 --- TGF-β signaling transduction --- p.3 / Chapter 1.1.2.1 --- Smad-dependent TGF-β signaling --- p.4 / Chapter 1.1.2.2 --- Smad-independent TGF-β signaling --- p.10 / Chapter 1.2 --- Chronic Kideny disease (CKD) --- p.12 / Chapter 1.2.1 --- Epidemiology of CKD --- p.12 / Chapter 1.2.2 --- Pathophysiology of CKD --- p.12 / Chapter 1.3 --- TGF-β signaling in renal diseases --- p.13 / Chapter 1.3.1 --- Role of TGF-β1 in renal diseases --- p.13 / Chapter 1.3.2 --- Potential role of TβRII in renal diseases --- p.15 / Chapter 1.3.3 --- Potential role of Smad2 in renal diseases --- p.17 / Chapter 1.3.4 --- Potential role of Smad4 in renal diseases --- p.20 / Chapter 1.3.5 --- Role of Smad7 in renal diseases --- p.23 / Chapter 1.3.6 --- Role of Smad-independent TGF-β signaling in renal disease --- p.24 / Chapter CHAPTER II --- MATERIALS AND METHODS --- p.26 / Chapter 2.1 --- MATERIALS --- p.27 / Chapter 2.1.1 --- Reagents and Equipments --- p.27 / Chapter 2.1.1.1 --- General reagents and equipments for cell culture --- p.27 / Chapter 2.1.1.2 --- General reagents and equipments for real-time RT-PCR --- p.28 / Chapter 2.1.1.3 --- General reagents and equipments for Masson Trichrome Staining --- p.28 / Chapter 2.1.1.4 --- General reagents and equipments for Immunohistochemistry --- p.29 / Chapter 2.1.1.5 --- General reagents and equipments for Immunofluorescence --- p.29 / Chapter 2.1.1.6 --- General reagents and equipments for Western Blot --- p.29 / Chapter 2.1.1.7 --- General reagents and equipments for Promoter assay --- p.31 / Chapter 2.1.1.8 --- General reagents and equipments for ChIP assay --- p.32 / Chapter 2.1.2 --- Buffers --- p.32 / Chapter 2.1.2.1 --- Buffers for Immunohistochemistry --- p.32 / Chapter 2.1.2.2 --- Buffers for Western blot --- p.35 / Chapter 2.1.3 --- Sequences of Primers and siRNAs --- p.40 / Chapter 2.1.4 --- Antibodies --- p.42 / Chapter 2.2 --- METHODS --- p.44 / Chapter 2.2.1 --- Animal model of Unilateral Ureteral Obstruction (UUO) --- p.44 / Chapter 2.2.2 --- Cell culture --- p.44 / Chapter 2.2.2.1 --- NRK52E cell line --- p.44 / Chapter 2.2.2.2 --- Smad2 WT/KO mouse embryonic fibroblasts (MEFs) --- p.45 / Chapter 2.2.2.3 --- Primary culture of kidney fibroblasts --- p.45 / Chapter 2.2.2.4 --- Primary culture of peritoneal macrophages --- p.46 / Chapter 2.2.3 --- PAS staining --- p.47 / Chapter 2.2.3.1 --- Tissue Handling and Fixation --- p.47 / Chapter 2.2.3.2 --- Tissue embedding and sectioning --- p.47 / Chapter 2.2.3.3 --- Preparation of Paraffin Tissue Sections for PAS staining --- p.48 / Chapter 2.2.3.4 --- PAS staining --- p.48 / Chapter 2.2.4 --- Real-time RT-PCR --- p.48 / Chapter 2.2.4.1 --- Total RNA isolation --- p.48 / Chapter 2.2.4.2 --- Reverse Transcription --- p.49 / Chapter 2.2.4.3 --- Real-time PCR --- p.50 / Chapter 2.2.4.4 --- Analysis of Real-time PCR --- p.50 / Chapter 2.2.5 --- Masson Trichrome Staining --- p.51 / Chapter 2.2.6 --- Immunohistochemistry --- p.52 / Chapter 2.2.6.1 --- Preparation of Paraffin Tissue Sections for IHC --- p.52 / Chapter 2.2.6.2 --- Antigen-Antibody Reaction --- p.52 / Chapter 2.2.6.3 --- Signal Detection --- p.53 / Chapter 2.2.6.4 --- Semi-quantification of Immunohistochemistry --- p.53 / Chapter 2.2.7 --- Immunofluorescence --- p.54 / Chapter 2.2.8 --- Western blot analysis --- p.54 / Chapter 2.2.8.1 --- Protein preparation --- p.55 / Chapter 2.2.8.2 --- SDS-PAGE --- p.56 / Chapter 2.2.8.3 --- Transmembrane of protein --- p.56 / Chapter 2.2.8.4 --- Incubation of first and second antibody --- p.57 / Chapter 2.2.8.5 --- Signal capture and analysis --- p.57 / Chapter 2.2.8.6 --- Stripping --- p.57 / Chapter 2.2.9 --- Promoter assay --- p.58 / Chapter 2.2.10 --- ChIP assay --- p.61 / Chapter 2.2.11 --- Statistical analysis --- p.62 / Chapter CHAPTER III --- THE DIVERSE ROLE OF TGF-BETA RECEPTOR II IN RENAL INFLAMMATION AND FIBROSIS --- p.63 / Chapter 3.1 --- INTRODUCTION --- p.64 / Chapter 3.2 --- AIMS --- p.64 / Chapter 3.3 --- MATERIALS AND METHODS --- p.66 / Chapter 3.3.1 --- Generation and characterization of TβRII conditional Knockout mice --- p.66 / Chapter 3.3.2 --- Generation and characterization of TβRII disrupted tubular epithelial cell line (NRK52E) and kidney interstitial fibroblasts --- p.67 / Chapter 3.3.3 --- Animal model of Unilateral Ureteral Obstruction --- p.67 / Chapter 3.3.4 --- Cell culture --- p.67 / Chapter 3.3.5 --- Real-time RT-PCR --- p.68 / Chapter 3.3.6 --- Masson Trichrome Staining --- p.68 / Chapter 3.3.7 --- Immunohistochemistry --- p.68 / Chapter 3.3.8 --- PAS staining --- p.69 / Chapter 3.3.9 --- Immunofluorescence --- p.69 / Chapter 3.3.10 --- Western blot analysis --- p.70 / Chapter 3.3.11 --- Promoter assay --- p.70 / Chapter 3.3.12 --- Statistical analysis --- p.70 / Chapter 3.4 --- RESULTS --- p.71 / Chapter 3.4.1 --- Characterization of TβRII conditional Knockout mice and TβRII disrupted cells --- p.71 / Chapter 3.4.2 --- Disruption of TβRII suppresses renal interstitial damage in the UUO kidney --- p.72 / Chapter 3.4.3 --- Disruption of TβRII suppresses renal fibrosis in UUO kidney and TGF-β1-induced fibrotic response in vitro --- p.76 / Chapter 3.4.3.1 --- Conditional knockout of TβRII from the kidney decreases the collagen I level in UUO kidney --- p.76 / Chapter 3.4.3.2 --- Disruption of TβRII inhibits TGF-β1 induced collagen I level in vitro --- p.79 / Chapter 3.4.3.3 --- Conditional knockout of TβRII from the kidney decreases the α-SMA positive cells infiltration in vivo --- p.81 / Chapter 3.4.3.4 --- Disruption of TβRII inhibits TGF-β1-induced α-SMA expression in vitro --- p.83 / Chapter 3.4.3.5 --- Conditional knockout of TβRII from the kidney decreases the FN level in UUO nephropathy --- p.85 / Chapter 3.4.3.6 --- Disruption of TβRII decreases TGF-β1-induced FN expression in vitro --- p.87 / Chapter 3.4.4 --- Disruption of TβRII impairs the TGF-β/Smad signaling in vivo in the UUO kidney and in vitro in TGF-β1 treated tubular epithelial cells and kidney fibroblasts --- p.89 / Chapter 3.4.4.1 --- Conditional knockout of TβRII decreases the UUO induced TGF-β1 expression in vivo and the TGF-β1 auto-induction in vitro --- p.89 / Chapter 3.4.4.2 --- Disrupted TβRII decreases CTGF level in the UUO nephropathy in vivo and the TGF-β1 induced CTGF mRNA level in vitro --- p.91 / Chapter 3.4.4.3 --- Conditional knockout of TβRII impairs the Smad3 signaling in the injured kidney --- p.93 / Chapter 3.4.4.4 --- Disrupted TβRII inhibits TGF-β1-induced Smad3 phosphorylation, P-Smad3 nuclear translocation and Smad3 responsive promoter activity in vitro --- p.95 / Chapter 3.4.4.5 --- Conditional knockout of TβRII doesn’t alter the activation of ERK and P38 signaling in the UUO kidney --- p.97 / Chapter 3.4.4.6 --- Disrupted TβRII inhibits TGF-β1-induced ERK and P38 phosphorylation in vitro --- p.99 / Chapter 3.4.5 --- Disruption of TβRII enhances inflammatory cytokines expression in the UUO kidney and impairs the anti-inflammatory effect of TGF-β1 in response to IL-1β triggered inflammatory response in the TEC cells --- p.101 / Chapter 3.4.5.1 --- Conditional knockout of TβRII increases the TNF-α expression in the UUO nephropathy --- p.101 / Chapter 3.4.5.2 --- Conditional knockout of TβRII increases the IL-1β expression in the UUO nephropathy --- p.103 / Chapter 3.4.5.3 --- Conditional knockout of TβRII doesn’t enhance the MCP-1 expression and macrophages infiltration in the UUO nephropathy --- p.104 / Chapter 3.4.5.4 --- Disruption of TβRII in TECs decreases the anti-inflammatory effect of TGF-β1 in response to IL-1β --- p.106 / Chapter 3.4.6 --- Disruption of TβRII enhances NFκB activation in vivo and in vitro --- p.108 / Chapter 3.5 --- DISCUSSION --- p.110 / Chapter 3.6 --- CONCLUSION --- p.114 / Chapter CHAPTER IV --- Smad2 protects against TGF-β/Smad3 mediated renal fibrosis --- p.115 / Chapter 4.1 --- INTRODUCTION --- p.116 / Chapter 4.2 --- AIMS --- p.117 / Chapter 4.3 --- MATERIALS AND METHODS --- p.117 / Chapter 4.3.1 --- Generation and characterization of Smad2 conditional Knockout mice --- p.117 / Chapter 4.3.2 --- Generation and characterization of Smad2 KO MEFs and Smad2 knockdown/overexpression tubular epithelial cell line (NRK52E) --- p.118 / Chapter 4.3.3 --- Animal model of Unilateral Ureteral Obstruction --- p.118 / Chapter 4.3.4 --- Cell culture --- p.118 / Chapter 4.3.5 --- Real-time RT-PCR --- p.119 / Chapter 4.3.6 --- Western blot analysis --- p.119 / Chapter 4.3.7 --- Immunohistochemistry --- p.119 / Chapter 4.3.8 --- Masson Trichrome Staining --- p.119 / Chapter 4.3.9 --- Immunofluorescence --- p.120 / Chapter 4.3.10 --- Promoter assay --- p.120 / Chapter 4.3.11 --- ChIP assay --- p.120 / Chapter 4.3.12 --- Statistical analysis --- p.120 / Chapter 4.4 --- RESULTS --- p.121 / Chapter 4.4.1 --- Characterization of Smad2 disrupted mice and cells --- p.121 / Chapter 4.4.1.1 --- Characterization of Smad2 conditional Knockout mice --- p.121 / Chapter 4.4.1.2 --- Characterization of Smad2 knockout MEFs, Smad2 knockdown/overexpression TECs --- p.123 / Chapter 4.4.2 --- Disruption of Smad2 further enhances renal fibrosis in vivo and in vitro --- p.124 / Chapter 4.4.2.1 --- Conditional knockout of Smad2 increases total collagen deposition and Col.I level in the UUO kidney --- p.124 / Chapter 4.4.2.2 --- Disruption of Smad2 in MEFs and TECs increases Col.I production in a time- and dosage-dependent manner in response to TGF-β1 --- p.126 / Chapter 4.4.2.3 --- Conditional knockout of Smad2 increases Col.III level in the UUO kidney --- p.128 / Chapter 4.4.2.4 --- Disruption of Smad2 in MEFs and TECs increases Col.III production in a time- and dosage-dependent manner in response to TGF-β1 --- p.130 / Chapter 4.4.3 --- Disruption of Smad2 further enhances renal fibrosis by suppressing the collagen degradation system in vivo and in vitro --- p.132 / Chapter 4.4.3.1 --- Conditional knockout of Smad2 inhibits the MMP2 mRNA while enhances TIMP-1 production in UUO kidney --- p.132 / Chapter 4.4.3.2 --- Disruption of Smad2 in MEFs and TECs decreases the MMP2 level while enhances TIMP-1 production in response to TGF-β1 --- p.133 / Chapter 4.4.4 --- Disruption of Smad2 further increases renal fibrosis by increasing TGF-β1 auto-induction and CTGF level in vivo and in vitro --- p.135 / Chapter 4.4.4.1 --- Disruption of Smad2 increases TGF-β1 auto-induction in vivo and in vitro --- p.135 / Chapter 4.4.4.2 --- Disruption of Smad2 increases CTGF synthesis in vivo and in vitro --- p.137 / Chapter 4.4.5 --- Disruption of Smad2 further increases renal fibrosis by enhancing Smad3 signaling in vivo and in vitro --- p.139 / Chapter 4.4.5.1 --- Conditional knockout of Smad2 further enhances Smad3 phosphorylation and nuclear translocation --- p.139 / Chapter 4.4.5.2 --- Disruption of Smad2 in MEFs and TECs further enhances Smad3 phosphorylation, nuclear translocation, Smad3 responsive promoter activity and the binding to the Col1A2 promoter --- p.141 / Chapter 4.4.6 --- Overexpression of Smad2 suppresses Smad3 signaling therefore ameliorates the TGF-β1-induced fibrotic response in TECs --- p.144 / Chapter 4.4.6.1 --- Overexpression of Smad2 ameliorates the TGF-β1- induced fibrotic response in TECs --- p.144 / Chapter 4.4.6.2 --- Overexpression of Smad2 suppresses Smad3 phosphorylation --- p.146 / Chapter 4.5 --- DISCUSSION --- p.147 / Chapter 4.6 --- CONCLUSION --- p.150 / Chapter CHAPTER V --- THE DISTINCT ROLE OF SMAD4 IN RENAL INFLAMMATION AND FIBROSIS --- p.151 / Chapter 5.1 --- INTRODUCTION --- p.152 / Chapter 5.2 --- AIMS --- p.152 / Chapter 5.3 --- MATERIALS AND METHODS --- p.153 / Chapter 5.3.1 --- Generation and characterization of Smad4 conditional Knockout mice --- p.153 / Chapter 5.3.2 --- Generation and characterization of Smad4 disrupted kidney interstitial fibroblasts and peritoneal macrophages --- p.153 / Chapter 5.3.3 --- Animal model of Unilateral Ureteral Obstruction (UUO) --- p.154 / Chapter 5.3.4 --- Cell culture --- p.154 / Chapter 5.3.5 --- Real-time RT-PCR --- p.155 / Chapter 5.3.6 --- Western blot analysis --- p.155 / Chapter 5.3.7 --- Immunohistochemistry --- p.155 / Chapter 5.3.8 --- Masson Trichrome Staining --- p.155 / Chapter 5.3.9 --- Promoter assay --- p.156 / Chapter 5.3.10 --- ChIP assay --- p.156 / Chapter 5.3.11 --- Statistical analysis --- p.156 / Chapter 5.4 --- RESULTS --- p.157 / Chapter 5.4.1 --- Characterization of Smad4 conditional Knockout mice and Smad4 disrupted cells --- p.157 / Chapter 5.4.2 --- Disruption of Smad4 suppresses renal fibrosis in the UUO nephropathy in vivo and TGF-β1-induced fibrotic response in vitro --- p.160 / Chapter 5.4.2.1 --- Conditional knockout of Smad4 from the kidney decreases the total collagen deposition in the UUO nephropathy --- p.160 / Chapter 5.4.2.2 --- Conditional knockout of Smad4 from the kidney decreases the Col.I production in the UUO nephropathy --- p.161 / Chapter 5.4.2.3 --- Disruption of Smad4 inhibits TGF-β1-induced Col.I production in vitro --- p.163 / Chapter 5.4.3 --- Disruption of Smad4 impairs the Smad3 function in vivo and in vitro --- p.164 / Chapter 5.4.3.1 --- Conditional knockout of Smad4 doesn’t decrease Smad3 phosphorylation and P-Smad3 nuclear translocation in vivo and in vitro --- p.164 / Chapter 5.4.3.2 --- Disruption of Smad4 inhibits TGF-β1 induced Smad3 promoter activity and the Smad3 binding to Col1A2 promoter --- p.166 / Chapter 5.4.3.3 --- Disruption of Smad4 has minimal effect on the activation of ERK signaling in vivo and in vitro --- p.167 / Chapter 5.4.4 --- Disruption of Smad4 enhances renal inflammation and impairs the anti-inflammatory effect of TGF-β1 in response to IL-1β triggered inflammatory response in vitro --- p.169 / Chapter 5.4.4.1 --- Conditional knockout of Smad4 increases the inflammatory cells infiltration --- p.169 / Chapter 5.4.4.2 --- Conditional knockout of Smad4 increases the TNFα expression in the UUO nephropathy --- p.171 / Chapter 5.4.4.3 --- Conditional knockout of Smad4 increases the IL-1β expression in the UUO nephropathy --- p.172 / Chapter 5.4.4.4 --- Conditional knockout of Smad4 increases the MCP-1 expression in the UUO nephropathy --- p.173 / Chapter 5.4.4.5 --- Conditional knockout of Smad4 increases the ICAM-1 level in the UUO nephropathy --- p.174 / Chapter 5.4.4.6 --- Time and dosage dependent experiments in response to IL-1β in macrophages --- p.175 / Chapter 5.4.4.7 --- Disruption of Smad4 in macrophages decreases the anti-inflammatory effect of TGF-β1 in response to IL-1β --- p.176 / Chapter 5.4.5 --- Disruption of Smad4 impairs the inhibitory effect of Smad7 on NFκB activation in vivo and in vitro --- p.178 / Chapter 5.4.5.1 --- Conditional knockout of Smad4 largely inhibits Smad7 level in UUO kidney --- p.178 / Chapter 5.4.5.2 --- Conditional knockout of Smad4 suppresses IκBα and further increases NF-κB p65 activation in UUO kidney --- p.180 / Chapter 5.4.5.3 --- Disruption of Smad4 inhibits Smad7 synthesis in macrophages --- p.182 / Chapter 5.4.5.4 --- Conditional knockout of Smad4 impair the inhibition effect of TGF-β1 on the activation of NFκB p65 in macrophages --- p.184 / Chapter 5.5 --- DISCUSSION --- p.186 / Chapter 5.6 --- CONCLUSION --- p.189 / Chapter CHAPTER VI --- SUMMARY AND DISCUSSION OF THE MAJOR FINDINGS --- p.190 / Chapter 6.1 --- SUMMARY AND DISCUSSION --- p.192 / Chapter 6.1.1 --- The diverse role of TβRII in renal inflammation and fibrosis both in vivo and in vitro --- p.192 / Chapter 6.1.2 --- Smad2 protects renal fibrosis by counter-regulating Smad3 signaling --- p.192 / Chapter 6.1.3 --- Disruption of Smad4 increased renal inflammation while suppressed the renal fibrosis in vivo and in vitro --- p.194 / Chapter 6.1.4 --- Comparative analysis of functions and related mechanisms between TβRII and Smad4 in renal disease --- p.195 / Chapter 6.1.5 --- Inadequacies of current work and future plan --- p.197 / Chapter 6.1.6 --- Perspectives (1) : The balance within the TGF-b/Smad signaling may determine the fate of renal diseases --- p.197 / Chapter 6.1.7 --- Perspectives(2)：The balance within the TGF-β/Smad signaling may determine the fate of renal diseases --- p.198 / Chapter 6.2 --- CONCLUSION --- p.201 / REFERENCES --- p.202 / PUBLICATION LIST --- p.232 / HONORS AND AWARDS --- p.237

Diss. (sammanfattning) Stockholm : Karol. inst., 2005. / Härtill 5 uppsatser.

Thesis (Ph. D.)--University of Alabama at Birmingham, 2008. / Title from first page of PDF file (viewed Feb. 13, 2009). Includes bibliographical references.