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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Ο ρόλος του SMAD σηματοδοτικού μονοπατιού στις σπειραματονεφρίτιδες του ανθρώπου

Κασιμάτης, Θεόδωρος Ι. 17 December 2008 (has links)
Οι σπειραματονεφρίτιδες (ΣΝ) αποτελούν μια ομάδα νοσημάτων του σπειράματος ανοσολογικής αιτιολογίας που σε πολλές περιπτώσεις οδηγούν στην πλήρη καταστροφή του νεφρικού παρεγχύματος με αποτέλεσμα τη νεφρική ίνωση και την ανάγκη υποκατάστασης της νεφρικής λειτουργίας με μεθόδους εξωνεφικής κάθαρσης. Τα τελευταία χρόνια έχει σημειωθεί σημαντική πρόοδος στην ανίχνευση των μοριακών μηχανισμών που οδηγούν στη νεφρική ίνωση. Κεντρικό ρόλο στη διαδικασία αυτή φαίνεται να διαδραματίζει το Smad σηματοδοτικό μονοπάτι που διαμεσολαβεί τα σήματα του TGF-β στα νεφρικά κύτταρα. Ο ρόλος του TGF-β στη νεφρική βλάβη είναι πλέον καλά τεκμηριωμένος. Αντίθετα ελάχιστα είναι γνωστά για την έκφραση και τη λειτουργία του Smad σηματοδοτικού μονοπατιού στις ανθρώπινες ΣΝ. Ο σκοπός της παρούσας μελέτης ήταν η διερεύνηση της έκφρασης των παραγόντων pSmad2/3, p300, Sp1, Smad7 και Ski (μορίων που συμμετέχουν στο Smad σηματοδοτικό μονοπάτι) σε νεφρικές βιοψίες ασθενών με ΣΝ και η ανίχνευση της δράσης τους όσον αφορά την παθογένεση και την εξέλιξη της νεφρικής βλάβης. Χρησιμοποιήθηκαν 157 βιοψίες ασθενών με ΣΝ και 15 φυσιολογικά νεφρικά δείγματα από ασθενείς που είχαν υποβληθεί σε νεφρεκτομή για καρκίνο του νεφρού. Οι σπειραματονεφρίτιδες κατηγοριοποιήθηκαν σε πρωτοπαθείς (n=91) και δευτεροπαθείς (n=66) ή υπερπλαστικές (n=86) και μη υπερπλαστικές (n=71). Η μελέτη της έκφρασης των pSmad2/3, p300, Sp1, Smad7 και Ski έγινε με τη χρήση ανοσοϊστοχημικής μεθόδου. Έγιναν συσχετίσεις με κλινικά δεδομένα των ασθενών (κρεατινίνη ορού και λεύκωμα ούρων 24ώρου), καθώς και δείκτες ιστολογικής βλάβης (σπειραματοσκλήρυνση, διάμεση ίνωση, σωληναριακή ατροφία και διάμεση φλεγμονή). Παρατηρήθηκε πολύ μεγάλη αύξηση της έκφρασης των pSmad2/3, Sp1 και p300 σε όλα τα σπειραματικά κύτταρα των ΣΝ σε σχέση με την ομάδα ελέγχου. Επίσης, αυξήθηκε η έκφραση του πυρηνικού Smad7 στις υπερπλαστικές κυρίως ΣΝ με ταυτόχρονη εξάλειψη της κυτταροπλασματικής έκφρασής του σε όλες τις ΣΝ και παράλληλη μείωση της έκφρασης του Ski. Όσον αφορά τα σωληνάρια, στα εγγύς παρατηρήθηκε αύξηση της έκφρασης των pSmad2/3, Sp1 και p300 σε όλες τις ΣΝ και αύξηση του πυρηνικού Smad7 στις υπερπλαστικές, ενώ στα άπω και τα αθροιστικά παρατηρήθηκε αύξηση της έκφρασης του pSmad2/3 και του πυρηνικού Smad7 με ταυτόχρονη μείωση του κυτταροπλασματικού Smad7. Το Ski παρουσίασε σημαντική μείωση της έκφρασής του στις ΣΝ σε όλους τους τύπους σωληναρίων. Η σπειραματική έκφραση των pSmad2/3, p300 και του πυρηνικού Smad7 ήταν αυξημένη στις υπερπλαστικές ΣΝ και κυρίως τις δευτεροπαθείς. Η σωληναριακή έκφραση των pSmad2/3 και Smad7 και η εγγύς σωληναριακή των p300, Sp1 και του κυτταροπλασματικού Smad7 ήταν επίσης αυξημένες στις υπερπλαστικές ΣΝ. Αντίθετα, το Ski δεν παρουσίασε διαφορές στην έκφραση μεταξύ των υπερπλαστικών και μη υπερπλαστικών ΣΝ. Ακόμη, ανιχνεύθηκαν σημαντικές συσχετίσεις μεταξύ μεταξύ της έκφρσης των pSmad2/3, p300, Sp1 και Smad7 στο σπείραμα και τα εγγύς σωληνάρια. Η σπειραματική και εγγύς σωληναριακή έκφραση των pSmad2/3, Sp1 και η σπειραματική του πυρηνικού Smad7 έδειξαν να συσχετίζονται θετικά με τα επίπεδα της κρεατινίνης του ορού, ενώ η έκφραση αυτών και του p300 σε διαφόρους τύπους σωληναρίων εμφάνισαν θετική στσχέτιση με δείκτες ιστολογικής βλάβης. Τέλος η έκφραση όλων των μορίων (εκτός του Ski) ήταν συχνότατη στις στοιχειώδεις σπειραματικές βλάβες. Συμπερασματικά, το Smad σηματοδοτικό μονοπάτι φαίνεται να ενεργοποιείται στις ανθρώπινες ΣΝ. Μάλιστα, η ενεργοποίησή του αυτή πιθανώς συμβάλλει στην παθογένεση αλλά και την εξέλιξη της νεφρικής βλάβης. Μελλοντικές θεραπευτικές στρατηγικές που θα στοχεύουν στην αναστολή του μονοπατιού αυτού ίσως συμβάλλουν στην παρεμπόδιση της εξέλιξης και τη θεραπεία των ανθρωπίνων ΣΝ. / -
72

The association of various HLA-A, -B and -DR loci with membranous glomerulonephritis, IgA nephropathy, and focal segmental glomerulosclerosis in KwaZulu-Natal renal patients.

January 2007 (has links)
This KwaZulu-Natal (KZN) based study investigates hypertension, glomerulonephritides and the rarity of IgA Nephropathy (IgAN) in Africans in association with the Human Leukocyte Antigen (HLA). A retrospective hypertensive study found a positive association with HLA-B40 (P c<0.05) and HLA-B15 (Pc<0.02) in Indians and Africans respectively. No association was found in Whites. A prospective study showed glomerulonephritides to be positively associated with HLA-A33 in Indians (Pc 0.049). No associations were found with glomerulonephritides in Africans and Whites. Combined Race groups show no HLA associations. HLA-A30; HLA-A34; HLA-A29; HLA-B42; HLA-B58; HLA-B70 and HLA-DR11 were extremely significantly higher in Africans compared to Indians and Whites (all P<0.0001). In conclusion, HLA-B40 and I 1LA-B15 are possible disease susceptibility markers in Indian and African hypertensives; HLA-A33 is a possible disease susceptibility marker for glomerulonephritides in Indians and alleles in linkage might be responsible for the rarity of IgAN in Africans but further studies need to be employed. / Thesis (M.Med)-University of KwaZulu-Natal, 2007.
73

Audinių inkstų patologijų dažnumas ir patologiniai morfologiniai pakitimai x žverėlių ūkyje / Mink kidney pathology rate ant pathologic morphologic changes in x farm

Servanski, Robert 05 March 2014 (has links)
Tyrimo tikslas: išsiaiškinti audinių inkstų patomorfologinius pokyčius ir inkstų pokyčių dažnumą žverėlių ūkyje. Taipogi nustatyti patologinius anatominius inkstų pakitimus, įvertinti mikroskopinius audinių inkstų pokyčius. Įvertinti ryšį tarp plazmocitozės su kitais morfologiniais pokyčiais. Tyrime atlikta, 50 audinių skrodimai. Atliktas detalus inkstų patologinių pokyčių tyrimas. Histologinėms sekcijoms dažymui naudoti hematoksilinas eozinas ir sirijaus raudonasis. Plazmocitozės pakitimai, inkstuose buvo analizuojami mikroskopiškai ir morfologiškai. Tyrimo rezultatai parodė, kad inkstų patologijos audinėms yra dažnos žverėlių ūkyje Lietuvoje. Nustatyta 88 % atvėjai iš tirtų audinių. Dažniausiai diagnozuoti inkstų pokyčiai, buvo plazminių ląstelių infiltracija, dar vadinama plazmocitozė 36%. Taip pat buvo diagnozuoti skirtingų tipų glomerulonefritai: minimalių pokyčių nefropatija 2%, ūmus nefritas 8%, židininė segmentinė glomerulosklerozė 14%, endokapiliarinis proliferacinis glomerulonefritas 6%, intersticinis nefritas 6%. Kartu su glomerulonefritais buvo ir kitų patologijų: inkstų lipidozė 6%, baltymų degeneracija 18%, Kanalėlių nekrozė 4%, Inksto infarktas 2%, Hemosiderozė 6%, podagra 2 % amiloidozė 2%, ir perivaskulitas 4%. / Mink kidney pathology rate ant pathologic morphologic changes in x farm. Kaunas, 2014 The coverage of work 43 table 6 picture 22 Reading list of : 55 sources Objectives and tasks of the research work to investigate mink kidney patomorphological changes and kidney alteration rate in x farm. Also establish patological anatomical kidney alterations, evaluate microscopic mink renal variation. Plasmacytosis infiltration in kidney evaluate connection with others pathologic morphologic alterations. Material and methods of the research. 50 mink autopsies have been performed. Detailed investigation of renal pathologic changes were done. Hematoxylin eosin and sirius red had been used as a staining method of histological sections. Changes of plasmacytosis in kidneys had been analysed microscopically and morphologically. Results and findings. It was found that renal pathologies in mink are frequent in X farm in Lithuania. Established over 88 % cases from investigated minks. Mostly diagnosed renal changes in mink was plasma cells infiltration also called plasmacytosis 36 %. Also have been diagnosed different types of GN : minimal change disease 2%, acute nephritis 8%, focal segmental glomerulosclerosis (FSGN) 14%, endocapillary proliferative (EPGN) 6%, intersticial nephritis 6%. Together with a glomerulonephritis some other pathologies was present: renal lipidosis 6%, cell swelling 18%, tubular necrosis 4%, renal infarct 2%, hemosiderosis 6%, gout 2 % amiloidosis 2%, and perivasculitis... [to full text]
74

The glomerular basement membrane and nephritis / Andrew Wootton

Wootton, Andrew January 1985 (has links)
Bibliography: leaves 119-136 / ix, 136 leaves, [9] leaves of plates : ill ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, 1986
75

Association between 3-Year Repetitive Isolated Hematuria and eGFR Deterioration in an Apparently Healthy Population: A Retrospective Cohort Study / 健康診断における3年間の反復する血尿と5年後のeGFR低下の関係:過去起点コホート研究

Ishida, Mami 23 March 2023 (has links)
京都大学 / 新制・課程博士 / 博士(社会健康医学) / 甲第24536号 / 社医博第128号 / 新制||社医||12(附属図書館) / 京都大学大学院医学研究科社会健康医学系専攻 / (主査)教授 近藤 尚己, 教授 西浦 博, 教授 柳田 素子 / 学位規則第4条第1項該当 / Doctor of Public Health / Kyoto University / DFAM
76

A case of Progressive Glomerulonephritis with Monoclonal Immunoglobulin Lambda Light Chain Deposition (LCDD)

Singh, Kanwardeep, Sriramoju, Vindhya, Singal, Sakshi, Spradling, Elnora N, Zafar, Rabia 05 April 2018 (has links)
Light Chain Deposition Disease (LCDD) is a type of monoclonal immunoglobulin deposition disease characterized by the non-amyloid deposition of monoclonal light chains in the tubular basement membranes and Bowman’s capsule. It was first described about 3 decades ago, but due to varied clinical presentations, many differential diagnoses and low incidence, it is both underrecognized and underreported. We present a case of 85-year-old female with past medical history significant for CKD and HTN, who presented with accelerated HTN, normocytic anemia and worsening renal function. Laboratory data showed Hgb <9.5 gm/dL, MCV 93 fL, Total protein 5.9, Albumin 3.2, Calcium 8.9, Serum Creatinine 2.37, BUN 45, Urine with hematuria (50–99 erythrocytes per high-power field) and nephrotic range proteinuria. Renal biopsy showed evidence of Membranoproliferative glomerulonephritis, with immunofluorescence features indicative of a monoclonal immunoglobulin deposition disease. Bone marrow biopsy showed mildly increased plasma cells (5-7%) confirmed to be clonal (lambda light chain) by flow cytometry, negative for Congo-Red stain. Although no underlying hematological abnormality like Multiple Myeloma or Amyloidosis was observed in this case, the renal pathological findings is consistent with proliferative glomerulonephritis with monoclonal IgG lambda deposits. There is no standard of care for the management of LCDD based on rarity of this condition. Many treatment modalities including chemotherapy and stem cell transplant have been tried. A combination of high dose melphalan or Cyclophosphamide with dexamethasone is preferred for Non-IgM type monoclonal protein kidney deposition, like in this case. Bortezomib and Thalidomide-based chemotherapy have been promising in recent research. For IgM type monoclonal protein deposition, Rituximab alone or in combination with cyclophosphamide and dexamethasone are used. This patient was not a good candidate for corticosteroid and chemotherapy or stem cell transplant due to old age (>77 years) and poor functional status, therefore, was started on hemodialysis. Following dialysis, improvement in renal function and general clinical condition was evident. The prognostic factors include age, degree of renal insufficiency at presentation affecting the renal prognosis, underlying hematologic disorder and extrarenal LC deposition. In this case, despite hemodialysis, long term survival and prognosis remain poor due to her inability to tolerate chemotherapy.
77

Characterizing the roles of gut microbiota, probiotic Lactobacilli and CX3CR1 in the development of autoimmunity in MRL/lpr mice

Cabana-Puig, Xavier 18 August 2022 (has links)
Systemic lupus erythematosus (SLE) is a multi-system autoimmune disease with no known cure. The crosstalk between the gut microbiota and the immune system plays an important role in the tolerance induction to self-antigens both in the intestinal mucosa and at the systemic level. The MRL/lpr mouse model exhibits lupus-like symptoms early in life due to multiple SLE susceptible loci of the MRL background, plus the Faslpr mutation that offers an accelerated model. Recently, we experienced a loss of disease phenotype in our in-house colony compared to the previous published phenotype of MRL/lpr mice. We thus compared mice newly obtained from The Jackson Laboratory (JAX) with our in-house MRL/lpr mice and found that the phenotypic drift, most significantly the attenuation of glomerulonephritis, was present in both colonies. In addition, while JAX mice and mice in our colony are genetically identical, there were minor differences in disease that might be due to differences in splenic microRNAs and the gut microbiota. Once confirming that our MRL/lpr mouse model was as good as that from JAX, we continued our investigation of the role of Lactobacilli in the pathogenesis of lupus-like disease in MRL/lpr mice. We previously published that the mixture of Lactobacillus reuteri (L. reuteri), L. oris, L. johnsonii, L. gasseri, and L. rhamnosus significantly attenuated disease in MRL/lpr mice by restoring the imbalance between regulatory T cells and T helper-17 cells. To further understand the role of Lactobacillus spp., we treated MRL/lpr mice with the combined culture supernatant of the 5 strains containing secreted metabolites, given that the metabolites may induce an immunosuppressive response. The results showed significant attenuation of the inflammation of the spleen and renal lymph nodes similar to the effect of the bacteria themselves. There was also a trending decrease of double-stranded DNA autoantibodies with the combined supernatant. We thus tested the strains individually but none was able to recapitulate the effect of the bacterial mixture. This suggests cell-to-cell contact among different strains of lactobacilli may be required in ameliorating the disease. With these results, we now have a better understanding of the role of probiotic Lactobacillus spp. against SLE. Future investigations will focus on the potential therapeutic effect of Lactobacillus spp. as a combination. Additionally, our group generated a Cx3cr1-deficient MRL/lpr mouse which exhibits a distinct phenotype of exacerbated glomerulonephritis with concurrent change of the gut microbiota composition compared to Cx3cr1+/+ MRL/lpr littermates. Interestingly, upon correction of the gut microbiota with Lactobacillus administration, the phenotype of exacerbated glomerulonephritis was reversed, suggesting that CX3CR1 controls glomerulonephritis in MRL/lpr mice through a gut microbiota-dependent mechanism. In addition, a collaborative project revealed that Cx3cr1 deficiency-mediated pathogenic mechanisms also contributed to SLE-associated cardiovascular disease in MRL/lpr mice. The results of these studies will lead to the identification of new therapeutic targets for the treatment of two severe manifestations, glomerulonephritis and cardiovascular disease, that together account for most of the morbidity and mortality in SLE. / Doctor of Philosophy / Systemic lupus erythematosus (SLE) is an autoimmune disease with no known cure. Commensal microbiota, mostly bacteria living in our gut, and the immune system have a strong relationship in maintaining a healthy state of the gut as well as the whole body. Alterations in the gut microbiota, known as dysbiosis, can facilitate SLE in human and animal models. Current treatments for SLE are primarily focused on using immunosuppressants, but the side effects are still a concern. The use of long-term nonselective immunosuppressant conducts a higher incidence of severe infections in SLE patients. It is thus necessary to develop new approaches and treatments against SLE. My dissertation research is focused on understanding how commensal bacteria influence in the pathogenesis of SLE. My studies have shown that environmental factors can manipulate the gut microbiota leading to different disease outcomes. In addition, following upon previously published studies from our laboratory, I have delineated the mechanism how a mixture of probiotic Lactobacilli can exert a beneficial effect against lupus. Finally, I have revealed a new, CX3CR1-mediated mechanism through which the gut microbiota controls kidney disease in the MRL/lpr lupus-prone mouse model.
78

Biomarker lipokalin 2 u dijagnostici primarnih glomerulonefritisa / Lipocalin 2 biomarker in diagnosis of primary glomerulonephritis

Stražmešter Majstorović Gordana 07 July 2016 (has links)
<p>Primarni glomerulonefritisi predstavljaju inflamatorna oboljenja bubrega, kod kojih su primarno zahvaćeni glomerulusi, ali promene na tubulointersticijumu imaju veliki značaj za tok i prognozu bolesti. Pored kliničko-laboratorijskih ispitivanja, perkutana biopsija bubrega zauzima značajno mesto u dijagnostici posebnih oblika glomerulonefritisa. Lipokalin vezan za neutrofilnu gelatinazu (NGAL) zauzima značajno mesto medju novijim biomarkerima u nefrologiji. Osnovna funkcija mu je transport gvoždja, ali ima ulogu i u regulaciji metabolizma gvoždja, regulaciji inflamacije, dok u masnom tkivu utiče na razvoj insulinske rezistencije i dijabetesa. Cilj ispitivanja je utvrditi nivo lipokalina 2 u serumu i urinu bolesnika sa primarnim glomerulonefritisom, te utvrditi postojanje korelacije izmedju nivoa lipokalina 2 i patohistolo&scaron;kog oblika glomerulonefritisa, stepenom bubrežne insuficijencije i brzinom progresije bubrežne insuficijencije. Takodje, cilj ispitivanja je bio analizirati povezanost lipokalina 2 sa odogovorom na primenjenu terapiju glomerulonefritisa. Ispitivanje je sprovedeno na 60 bolesnika sa dijagnozom primarnih glomerulonefritisa. Nivo lipokalina 2 je odredjivan pri postavljanju dijagnoze i nakon minimalno &scaron;est meseci lečenja. Rezultati studije ukazuju da bolesnici sa primarnim glomerulonefritisom imaju značajno veće nivoe lipokalina 2 u odnosu na zdrave osobe. Bolesnici sa proliferativnim oblicima primarnih glomerulonefritisa imaju veće nivoe NGAL-a u serumu i odnosa uNGAL/kreatinin, ali razlika nije statistički značajna. Nije utvrdjeno postojanje značajne razlike u prosečnim nivoima NGAL-a u serumu, niti urinu, pri postavljanju dijagnoze, izmedju bolesnika sa pozitivnim i negativnim efektom lečenja primarnog glomerulonefritisa. Utvrdjeno je postojanje korelacije izmedju nivoa NGAL-a u serumu i vrednosti kreatinina, ureje, mokraćne kiseline, klirensa kreatinina i broja leukocita, dok je sa nivoom NGAL-a u urinu utvrdjena korelacija sa klirensom kreatinina, dnevnom proteinurijom i serumskim albuminima. Utvrdjeno je postojanje statistički značajne razlike u prosečnim nivoima NGAL-a u serumu u zavisnosti od stadijuma bubrežne insufijencije. Nije utvrdjeno postojanje značajne razlike u prosečnim nivoima NGAL-a u serumu pri postavljanju dijagnoze, izmedju bolesnika sa povoljnim i nepovoljnim efektom lečenja na bubrežnu funkciju.</p> / <p>The primary glomerulonephritis are inflammatory kidney diseases. Glomerulus are primarily affected, but tubulointerstitial changes are very important for course and prognosis of the disease. In addition to clinical and laboratory testing, percutaneous renal biopsy has an important place in the diagnosis of specific forms of glomerulonephritis. Neutrophil gelatinaseassociated lipocalin (NGAL) occupies an important place among the newer biomarkers in nephrology. The main function of NGAL is transport of iron, whether it has a role in the regulation of iron metabolism, regulation of inflammation, while in adipose tissue affects the development of insulin resistance and diabetes. The aim of this study was to determine the level of lipocalin 2 in serum and urine of patients with primary glomerulonephritis and determine the existence of a correlation between the level of lipocalin 2 and histological forms of glomerulonephritis, the degree of renal insufficiency and speed of progression of renal insufficiency. Also, the aim of this study was to analyze the association of lipocalin 2 with the effect of therapy for glomerulonephritis. The study was conducted on 60 patients diagnosed with primary glomerulonephritis. The levels of lipocalin 2 were determined at diagnosis and after a minimum of six months of treatment. The study results show that patients with primary glomerulonephritis have significantly higher levels of lipocalin 2 compared to healthy people. Patients with proliferative forms of primary glomerulonephritis have higher levels of NGAL in serum and ratio uNGAL/creatinine, but the difference was not statistically significant. There was no significant differences in average levels of NGAL in serum or urine at the beginning, between patients with positive and negative effects of the treatment of primary glomerulonephritis. Correlation was found between the level of NGAL in serum and creatinine, urea, uric acid, creatinine clearance and the number of leukocytes, while the level of NGAL in urine correlated with creatinine clearance, the daily proteinuria and serum albumin. Statistically significant differences in mean levels of NGAL in serum depending on the severity of renal insufficiency were found. No evidence of significant differences in average levels of NGAL in serum at the beginning, among patients with favorable and unfavorable effects of treatment on renal function were found.</p>
79

Rôle de l'épithélium et de l'endothélium rénal au cours des glomérulopathies expérimentales. Etude des glomérulonéphrites inflammatoires et des glomérulopathies toxique et hypertensive / Role of renal epithelium and endothelium in experimental glomerular diseases

Luque Rincon, Yosu 26 October 2016 (has links)
Les maladies glomérulaires sont une des principales causes d'insuffisance rénale terminale de nos jours et constituent un problème de santé publique. Le concept classique dans les glomérulopathies accorde à l'agression systémique immune, toxique ou hypertensive le rôle principal dans la formation des lésions glomérulaires. L'hypothèse développée dans ce manuscrit est que épithélium et endothélium, deux composants principaux du parenchyme rénal sont des acteurs majeurs dans la formation des lésions glomérulaires. Trois modèles expérimentaux de glomérulopathie (inflammatoire, toxique et hypertensive) chez la souris nous ont permis d'étudier une voie de signalisation épithéliale γC/JAK/STAT classiquement décrite dans les cellules immunitaires et le système de réponse à l'hypoxie endothéliale afin d'étayer cette hypothèse. Après avoir discuté le rôle principal classiquement attribué aux lymphocytes T dans le modèle anti-membrane basale glomérulaire, un modèle animal de glomérulonéphrite inflammatoire, nous avons démontré le rôle protecteur de la chaîne γ commune (γC) glomérulaire et de sa protéine d'aval STAT5 dans le podocyte au cours du modèle anti-MBG et de la néphropathie à l'adriamycine. Enfin, nous avons étudié le rôle protecteur de EPAS1 (HIF-2α), une sous-unité régulatrice du complexe HIF, dans l'endothélium au cours des lésions glomérulaires hypertensives. Au total, ce travail met en évidence le rôle majeur de l'épithélium et l'endothélium rénal, étroitement liés, dans la formation des lésions glomérulaires. Le parenchyme rénal représente un acteur à part entière dans la physiopathologie de ces lésions comme le montrent les travaux sur les systèmes γC/STAT5 et HIF. / Glomerular diseases are a leading cause of kidney failure and represent a public health problem. Classically, systemic effectors such as the immune system, drug toxicity or hypertension are thought to be the main drivers of glomerular diseases. The hypothesis developed in this manuscript is that epithelium and endothelium, the two main components of the renal parenchyma, are major players in the formation of glomerular lesions. Three experimental models of glomerular disease (inflammatory, toxic and hypertensive) in mice allowed us to study epithelial γC / JAK / STAT signaling classically described in immune cells and the endothelial hypoxia inducible system in order to support this hypothesis. After discussing the main role traditionally assigned to T cells in the anti- glomerular basement membrane model, an animal model of inflammatory glomerulonephritis, we demonstrated the protective role of the glomerular interleukin common γ chain (γC) receptor and its dependent podocyte-specific STAT5 during the anti-GBM model and adriamycin nephropathy. We then showed the protective role of endothelial EPAS1 (HIF-2α), a regulatory subunit of HIF complex in focal segmental glomerulosclerosis (FSGS) induced by angiotensin II. In total, this work highlights the important role of the closely linked renal epithelium and endothelium in the formation of glomerular lesions using three experimental models of glomerular diseases. The renal parenchyma is a full player in the pathophysiology of these lesions as shown by the works studying γC / JAK / STAT and HIF systems.
80

Expressão intra-renal dos RNA mensageiros de proteínas associadas ao podócito e de fatores pro fibróticos em glomerulopatias primárias e secundárias

Souza, Maysa Lucena de January 2015 (has links)
Introdução: A podocitopenia e a podocitúria são marcadores de injúria glomerular em podocitopatias (POD) e glomerulonefrites proliferativas (GNsP), e mesmo em fases iniciais destas doenças mecanismos pró-fibróticos indutores de glomeruloesclerose e fibrose renal progressiva estão ativados. Objetivo: Avaliar pacientes portadores de glomerulopatias biopsiados em diferentes tempos de evolução clínica, correlacionando lesões morfológicas dos compartimentos glomerular e túbulo-intersticial com a expressão dos RNAm de proteínas associadas ao podócito e de fatores pró-fibróticos no tecido renal. Materiais e Métodos: Foram incluídos no estudo oitenta e quatro pacientes adultos portadores de glomerulopatias de diferentes etiologias submetidos à biópsia renal por indicação clínica. As lesões histológicas foram individualizadas e a porcentagem de fibrose intersticial e atrofia tubular foi quantificada na coloração de Tricrômio de Masson. Foram mensurados no tecido renal o log 10 do RNAm pela reação em cadeia da polimerase em tempo real das proteínas associadas ao podócito alfa actinina-4, podocina e podocalixina e dos fatores pró-fibróticos fator de crescimento transformador ₁ (TGF₁), fator de crescimento do tecido conectivo (CTGF) e fator de crescimento derivado do endotélio A (VEGF-A). A secção livre de neoplasia de rins removidos por câncer renal foram usados como controles da expressão dos RNAm. Resultados: No grupo POD, os diagnósticos histopatológicos foram: Glomeruloesclerose segmentar e focal (n=20), GN membranosa (n=12), Nefropatia diabética (n=9) e Lesões mínimas (n=7); no grupo GNsP foram Nefropatia por IgA (n=15), GN membranoproliferativa (n=5), Nefrite lúpica (n=5) e GN proliferativa mesangial (n=4), e outros diagnósticos (n=7). O RNAm do tecido renal nos pacientes com POD e GNsP foi significativamente menor comparado ao dos controles para todos os genes estudados. A presença de crescentes, independente do estágio evolutivo, foi associada à maior expressão do RNAm de alfa actinina-4 (p=0,04), podocina (p=0,01) e podocalixina (p=0,038). O RNAm dos genes pró-fibróticos também estava inibido comparado a sua expressão no rim normal. Nas GNsP, o VEGF-A (p<0,001) e o CTGF (p<0,001) foram os genes com menor nível de expressão comparado aos controles. Em relação às biópsias com lesões crescênticas, tanto o RNAm do TGFβ1 (p=0,001) como do CTGF (p=0,041) tiveram maior expressão comparado ao RNAm das biópsias sem crescentes. Nas biópsias com fibrose intersticial superior a 30%, a expressão do RNAm de TGFβ1, (p=0,038) e do VEGF-A (p=0,040) foi maior do que nas biópsias com fibrose leve. O maior tempo entre o início da doença clínica e a realização da biópsia renal não teve influência detectável na expressão tecidual do RNAm dos biomarcadores estudados. Conclusões: Pacientes com podocitopatias ou glomerulonefrites proliferativas apresentaram inibição da expressão do RNAm de proteínas associadas ao podócito e de fatores indutores de fibrose renal, achados compatíveis com injúria podocitária e podocitopenia. Nas biópsias renais com maior grau de fibrose intersticial e atrofia tubular, assim também como naquelas com lesões crescênticas, a expressão do RNAm de fatores fibrogênicos como TGF-β1 e CTGF foi significativamente aumentada, o que pode sugerir supra-regulação de moléculas associadas a mecanismos de fibrose renal e patologia glomerular. / Introduction: Both podocitopenia and podocyturia are markers of glomerular injury in podocytopathies (POD) and proliferative glomerulonephritis (PGNs), and even in the early stages of these diseases pro-fibrotic mechanisms leading to glomerulosclerosis and progressive renal fibrosis are running. Objective: This study evaluated patients with glomerulopathies who were biopsied at different times of clinical evolution, correlating morphological lesions of the glomerular and tubulointerstitial compartments with renal messenger RNA (mRNA) expression of podocyteassociated proteins and pro-fibrotic factors. Materials and Methods: The study included eighty-four adult patients with glomerulopathies of different etiologies undergoing kidney biopsy as clinically indicated. The histological lesions were individualized and the percentage of interstitial fibrosis and tubular atrophy was quantified on Trichrome Masson staining. Tissue log 10 mRNA of the podocyte proteins alpha-actinin-4, podocin and podocalyxin and of the pro-fibrotic factors transforming growth factor β₁ (TGFβ₁), connective tissue growth factor (CTGF) and vascular endothelium growth factor A (VEGF-A) was measured by real time polymerase chain reaction. The sections free of neoplasia of kidneys removed for renal cancer were used as controls for the mRNA tissue expression. Results: Results: In the POD group, the histopathological diagnoses were: focal segmental glomerulosclerosis (n=20), membranous (n=12), diabetic nephropathy (n=9) and minimal changes (n=7); in PGNs group were IgA nephropathy (n=15), membranoproliferative (n=5), lupus nephritis (n=5) and mesangial proliferative (n=4), and other diagnoses (n=7). Messenger RNA expression of POD and PGNs groups was significantly lower compared to controls for all the studied genes. The presence of crescents, regardless of their evolutive stage, was associated with higher mRNA expression of alpha-actinin-4 (p=0.04), podocin (p=0.01) and podocalyxin (p=0.038). The mRNA of pro-fibrotic genes was also inhibited compared to their expression in normal kidneys. In PGNs, VEGF-A (p<0.001) and CTGF (p<0.001) were the genes with lowest mRNA levels compared to controls. Regarding the biopsies with crescentic lesions, both the mRNA of TGFβ1 (p=0.001) and CTGF (p=0.041) were highly expressed as compared to those of biopsies without crescents. In biopsies with moderate to severe interstitial fibrosis (more than 30%), the mRNA expression of TGFβ1 (p=0.038) and VEGF-A (p=0.040) was highly expressed compared to biopsies with mild fibrosis. A longer interval between the clinical disease and the performance of kidney biopsy did not have a detectable influence on tissue mRNA expression of the studied biomarkers. Conclusions: Patients with POD or PGNs presented inhibition of the mRNA expression of podocyte-associated proteins and pro-fibrotic factors, findings that are consistent with podocyte injury and podocitopenia. In renal biopsies with a higher degree of interstitial fibrosis and tubular atrophy, as well as those with crescentic lesions, the mRNA expression of fibrogenic factors such as TGF-β1 and CTGF was significantly increased, which may suggest upregulation of molecules associated with mechanisms of renal fibrosis and glomerular pathology.

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