TY - JOUR A1 - Assfalg, Volker A1 - Selig, Katharina A1 - Tolksdorf, Johanna A1 - van Meel, Marieke A1 - de Vries, Erwin A1 - Ramsoebhag, Anne‐Marie A1 - Rahmel, Axel A1 - Renders, Lutz A1 - Novotny, Alexander A1 - Matevossian, Edouard A1 - Schneeberger, Stefan A1 - Rosenkranz, Alexander R. A1 - Berlakovich, Gabriela A1 - Ysebaert, Dirk A1 - Knops, Noël A1 - Kuypers, Dirk A1 - Weekers, Laurent A1 - Muehlfeld, Anja A1 - Rump, Lars‐Christian A1 - Hauser, Ingeborg A1 - Pisarski, Przemyslaw A1 - Weimer, Rolf A1 - Fornara, Paolo A1 - Fischer, Lutz A1 - Kliem, Volker A1 - Sester, Urban A1 - Stippel, Dirk A1 - Arns, Wolfgang A1 - Hau, Hans‐Michael A1 - Nitschke, Martin A1 - Hoyer, Joachim A1 - Thorban, Stefan A1 - Weinmann‐Menke, Julia A1 - Heller, Katharina A1 - Banas, Bernhard A1 - Schwenger, Vedat A1 - Nadalin, Silvio A1 - Lopau, Kai A1 - Hüser, Norbert A1 - Heemann, Uwe T1 - Repeated kidney re‐transplantation—the Eurotransplant experience: a retrospective multicenter outcome analysis JF - Transplant International N2 - In Eurotransplant kidney allocation system (ETKAS), candidates can be considered unlimitedly for repeated re‐transplantation. Data on outcome and benefit are indeterminate. We performed a retrospective 15‐year patient and graft outcome data analysis from 1464 recipients of a third or fourth or higher sequential deceased donor renal transplantation (DDRT) from 42 transplant centers. Repeated re‐DDRT recipients were younger (mean 43.0 vs. 50.2 years) compared to first DDRT recipients. They received grafts with more favorable HLA matches (89.0% vs. 84.5%) but thereby no statistically significant improvement of patient and graft outcome was found as comparatively demonstrated in 1st DDRT. In the multivariate modeling accounting for confounding factors, mortality and graft loss after 3rd and ≥4th DDRT (P < 0.001 each) and death with functioning graft (DwFG) after 3rd DDRT (P = 0.001) were higher as compared to 1st DDRT. The incidence of primary nonfunction (PNF) was also significantly higher in re‐DDRT (12.7%) than in 1st DDRT (7.1%; P < 0.001). Facing organ shortage, increasing waiting time, and considerable mortality on dialysis, we question the current policy of repeated re‐DDRT. The data from this survey propose better HLA matching in first DDRT and second DDRT and careful selection of candidates, especially for ≥4th DDRT. KW - allocation KW - child KW - fourth KW - graft KW - kidney KW - loss KW - repeated KW - re‐transplantation KW - survival KW - third Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-214161 VL - 33 IS - 6 SP - 617 EP - 631 ER - TY - JOUR A1 - Bachmann, Friederike A1 - Schreder, Martin A1 - Engelhardt, Monika A1 - Langer, Christian A1 - Wolleschak, Denise A1 - Mügge, Lars Olof A1 - Dürk, Heinz A1 - Schäfer-Eckart, Kerstin A1 - Blau, Igor Wolfgang A1 - Gramatzki, Martin A1 - Liebisch, Peter A1 - Grube, Matthias A1 - Metzler, Ivana v. A1 - Bassermann, Florian A1 - Metzner, Bernd A1 - Röllig, Christoph A1 - Hertenstein, Bernd A1 - Khandanpour, Cyrus A1 - Dechow, Tobias A1 - Hebart, Holger A1 - Jung, Wolfram A1 - Theurich, Sebastian A1 - Maschmeyer, Georg A1 - Salwender, Hans A1 - Hess, Georg A1 - Bittrich, Max A1 - Rasche, Leo A1 - Brioli, Annamaria A1 - Eckardt, Kai-Uwe A1 - Straka, Christian A1 - Held, Swantje A1 - Einsele, Hermann A1 - Knop, Stefan T1 - Kinetics of renal function during induction in newly diagnosed multiple myeloma: results of two prospective studies by the German Myeloma Study Group DSMM JF - Cancers N2 - Background: Preservation of kidney function in newly diagnosed (ND) multiple myeloma (MM) helps to prevent excess toxicity. Patients (pts) from two prospective trials were analyzed, provided postinduction (PInd) restaging was performed. Pts received three cycles with bortezomib (btz), cyclophosphamide, and dexamethasone (dex; VCD) or btz, lenalidomide (len), and dex (VRd) or len, adriamycin, and dex (RAD). The minimum required estimated glomerular filtration rate (eGFR) was >30 mL/min. We analyzed the percent change of the renal function using the International Myeloma Working Group (IMWG) criteria and Kidney Disease: Improving Global Outcomes (KDIGO)-defined categories. Results: Seven hundred and seventy-two patients were eligible. Three hundred and fifty-six received VCD, 214 VRd, and 202 RAD. VCD patients had the best baseline eGFR. The proportion of pts with eGFR <45 mL/min decreased from 7.3% at baseline to 1.9% PInd (p < 0.0001). Thirty-seven point one percent of VCD versus 49% of VRd patients had a decrease of GFR (p = 0.0872). IMWG-defined “renal complete response (CRrenal)” was achieved in 17/25 (68%) pts after VCD, 12/19 (63%) after RAD, and 14/27 (52%) after VRd (p = 0.4747). Conclusions: Analyzing a large and representative newly diagnosed myeloma (NDMM) group, we found no difference in CRrenal that occurred independently from the myeloma response across the three regimens. A trend towards deterioration of the renal function with VRd versus VCD may be explained by a better pretreatment “renal fitness” in the latter group. KW - multiple myeloma KW - renal failure KW - kidney KW - bortezomib KW - lenalidomide KW - induction regimen Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-234139 SN - 2072-6694 VL - 13 IS - 6 ER - TY - JOUR A1 - Betz, Boris A1 - Schneider, Reinhard A1 - Kress, Tobias A1 - Schick, Martin Alexander A1 - Wanner, Christoph A1 - Sauvant, Christoph T1 - Rosiglitazone Affects Nitric Oxide Synthases and Improves Renal Outcome in a Rat Model of Severe Ischemia/Reperfusion Injury JF - PPAR Research N2 - Background. Nitric oxide (NO)-signal transduction plays an important role in renal ischemia/reperfusion (I/R) injury. NO produced by endothelial NO-synthase (eNOS) has protective functions whereas NO from inducible NO-synthase (iNOS) induces impairment. Rosiglitazone (RGZ), a peroxisome proliferator-activated receptor (PPAR)-gamma agonist exerted beneficial effects after renal I/R injury, so we investigated whether this might be causally linked with NOS imbalance. Methods. RGZ (5 mg/kg) was administered i.p. to SD-rats (f) subjected to bilateral renal ischemia (60 min). Following 24 h of reperfusion, inulin-and PAH-clearance as well as PAH-net secretion were determined. Morphological alterations were graded by histopathological scoring. Plasma NOx-production was measured. eNOS and iNOS expression was analyzed by qPCR. Cleaved caspase 3 (CC3) was determined as an apoptosis indicator and ED1 as a marker of macrophage infiltration in renal tissue. Results. RGZ improves renal function after renal I/R injury (PAH-/inulin-clearance, PAH-net secretion) and reduces histomorphological injury. Additionally, RGZ reduces NOx plasma levels, ED-1 positive cell infiltration and CC3 expression. iNOS-mRNA is reduced whereas eNOS-mRNA is increased by RGZ. Conclusion. RGZ has protective properties after severe renal I/R injury. Alterations of the NO pathway regarding eNOS and iNOS could be an explanation of the underlying mechanism of RGZ protection in renal I/R injury. KW - dysfunction KW - activated-receptor gamma KW - ischemia-reperfusion injury KW - failure KW - kidney KW - agnoists KW - mices KW - inos KW - pathophysiology KW - pioglitazone Y1 - 2012 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-130872 VL - 2012 IS - Article ID 219319 ER - TY - THES A1 - Hartmann, Sonja T1 - Relevance of antibodies targeting the beta1-adrenergic receptor for renal function T1 - Relevanz von Antikörpern gegen den beta1-adrenergen Rezeptor für die Nierenfunktion N2 - Functionally active (conformational) autoantibodies directed against the β1-adrenergic receptor (β1-AR) are supposed to have a pathogenic relevance in human heart failure, particularly in idiopathic dilated cardiomyopathy (DCM). Prevalence of anti-β1-autoantibodies (anti-β1-aabs) in the healthy population is almost negligible, whereas it amounts to up to 30% in heart failure patients with idiopathic DCM. As β1-ARs are not restricted to the heart and are also highly expressed in particular segments of the nephron, it is conceivable that such autoantibodies might also affect kidney function to some extent through the activation of renal β1-ARs. In the kidney, β1-ARs are highly abundant in the juxtaglomerular apparatus, the distal convoluted tubules, the collecting duct, and the renal arteries. However, the functional significance of β1-ARs at these particular sites along the nephron is poorly understood, as are the effects of conformational stimulating anti-β1-aabs on renal β1-ARs. From the available literature, it is well known that the β1-adrenergic system is involved in, e.g., the regulation of renin-secretion from juxtaglomerular cells. In addition, the β1-adrenergic system is thought to be involved in the regulation of the urine pH via type B-intercalated cells in the collecting duct. In contrast, the regulation of salt- and fluid-secretion in the medullary collecting duct appears to occur independently from the SNS. As a consequence, the present work aimed to unravel the potential pathophysiological links between renal function, alterations in the cardiovascular system, and circulating agonist-like anti- β1-abs. We analyzed possible renal effects of anti-β1-abs in a human-analogous rat model. After immunization with a GST-fusion protein containing the second extracellular loop (β1-ECII) of the human β1-AR, Lewis-rats develop functionally active, stimulating, conformational anti-β1-ECII-abs. Within the first 6 months, anti-β1-ECII-ab-positive animals develop a hypertensive phenotype, which after 9 months evolves into a DCM phenotype. In n=40 GST/ β1-ECII-immunized Lewis rats and n=40 age-matched, 0.9% NaCl-injected control animals, we sequentially (i.e. at months 1, 2, 3, 6, 9, 12, 15, and 18 after start of immunization) analyzed the changes in renal function on a molecular, functional, and structural level. We could show that the presence of stimulating anti-β1-ECII-abs – even though having detrimental effects on the heart – has only a minor impact on kidney function and structure. Within the first 3 months after induction of anti-β1-ECII-abs, the levels and activity of renin were significantly increased in immunized compared to corresponding control animals, which was confirmed by experiments on isolated perfused kidneys, in which anti-β1-ECII-abs were able to directly induce the liberation of renin. However, within several weeks the initial anti-β1-ECII-ab-mediated RAAS activation was counter-regulated by auto-regulatory mechanisms activated in the kidney. Similarly, glomerular filtration rate (GFR) and renal blood flow (RBF) were initially decreased in the presence of the stimulating anti-β1-ECII-abs, but returned to control values within 3 months after immunization of the animals. Although expression of several pro-fibrotic markers was significantly up-regulated in anti-β1-ECII-ab-positive rats, no significant differences were noted on a histomorphological level with regard to the occurrence of renal fibrosis, glomerular damage, tubular damage, and perivascular fibrosis. Only a mild decrease in glomerular filtration function was observed in the kidneys of anti-β1-ECII-ab-positive animals from immunization-month 12 on, apparent by increased levels of urinary protein. Even though anti-β1-ECII-abs were able to induce mild changes in renal function, their effects were not strong enough to critically damage the kidneys in our rat-model. Differences between immunized anti-β1-ECII-ab-positive and corresponding control rats at later time-points (that is, from immunization-month 12 on) are most likely secondary to the progressive heart failure phenotype that immunized animals develop in the course of the experiment. The present study is the first to focus on the effects of stimulating anti-β1-ECII-abs on the kidney, and on the prevalence of these effects for the heart (referred to as cardio-renal crosstalk). Although our results were obtained in a rat model, they might contribute to better understand the situation in anti-β1-AR-aab-positive human patients. Following the results of our experiments, treatment of such patients should focus on direct and specific neutralization/elimination of stimulating anti-β1-ECII-aab or at least comprise therapeutic strategies that counteract the anti-β1-ECII-aab-effects on the heart by standard treatment for heart failure (i.e. ACE inhibitors, AT1-receptor blockers, and β-blockers) according to current guidelines. N2 - Funktionell aktive, konformationelle Autoantikörper, die gegen den β1-adrenergen Rezeptor (β1-AR) gerichtet sind, sind vermutlich pathologisch relevant bei Herzinsuffizienz, insbesondere bei der idiopathischen Dilativen Kardiomyopathie (DCM). Die Prävalenz solcher Antikörper ist in der gesunden Population vernachlässigbar, wohingegen sie bei der idiopathischen DCM 30% erreicht. Da β1-AR nicht nur im Herzen, sondern auch in der Niere stark exprimiert werden, ist naheliegend, dass solche Antikörper über eine Stimulation renaler β1-AR auch die Nierenfunktion beeinflussen können. In der Niere werden β1-AR überwiegend im juxtaglomerulären Apparat, im distalen Tubulus, in den Sammelrohren und in den renalen Arterien exprimiert. Die Bedeutung der in diesen Bereichen hohen Expression von β1-AR für die Nierenfunktion ist noch nicht vollständig geklärt, ebenso wie die renalen Effekte von stimulierenden β1-AR-Antikörpern. Aus der Literatur ist bekannt, dass das β1-adrenerge System unter anderem an der Renin-Sekretion der juxtaglomerulären Zellen beteiligt ist. Außerdem wird vermutet, dass das β1-adrenerge System in die Regulation des pH-Wertes des Urins über die Typ B-interkalierenden Zellen des Sammelrohrs eingreift, wohingegen die Regulation der Salz- und Wasserexkretion im medullären Sammelrohr wahrscheinlich unabhängig vom sympathischen Nervensystem abläuft. Die vorliegende Arbeit zielt darauf ab, die potentiellen pathophysiologischen Zusammenhänge zwischen renaler Funktion, Änderungen innerhalb des kardiovaskulären Systems und zirkulierenden, agonist-ähnlichen anti-β1-Autoantikörpern darzustellen. Wir haben die möglichen renalen Effekte der anti-β1-AK in einem human-ähnlichen Ratten-Modell untersucht. Nach Immunisierung mit einem GST-Fusionsprotein, welches den zweiten extrazellulären Loop des β1-AR beinhaltet, entwickeln Lewis-Ratten funktionell aktive, stimulierende Antikörper gegen β1-ECII. Anti-β1-ECII-AK-positive Tiere entwickeln nach ca. 6 Monaten einen hypertensiven Phänotyp, welcher nach 9 Monaten in einen DCM Phänotyp übergeht. Wir haben Änderungen der renalen Funktion auf molekularer, funktioneller, und struktureller Ebene in n=40 GST/ β1-ECII-immunisierten Lewis-Ratten und n=40 altersgleichen 0.9% NaCl-injizierten Kontrolltieren sequenziell (d.h. 1, 2, 3, 6, 9, 12, 15 und 18 Monate nach Beginn der Immunisierung) analysiert. Wir konnten zeigen, dass die stimulierenden anti-β1-ECII-Antikörper – obwohl sie eine schädigende Wirkung auf das Herz haben – die Nierenfunktion und -Struktur nur gering beeinflussen. In den ersten Monaten nach Induktion der anti-β1-ECII-AK stieg die Reninkonzentration und -aktivität in den immunisierten Tieren im Vergleich zu den entsprechenden Kontrollen signifikant an. Dieses Ergebnis konnte im Model der isolierten perfundierten Niere bestätigen werden, in dem anti-β1-ECII-AK eine direkte Freisetzung von Renin induzierten. Diese frühe AK-vermittelte Aktivierung des RAAS wurde jedoch innerhalb weniger Wochen durch autoregulatorische Mechanismen der Niere aufgehoben. Ebenso waren anfangs die glomeruläre Filtrationsrate und der renale Blutfluss in anti-β1-ECII-AK-positiven Ratten vermindert, kehrten jedoch nach 3 Monaten zu den Werten der Kontrolltiere zurück. Obwohl die Expression mehrerer pro-fibrotischer Marker signifikant erhöht war, konnten keine signifikanten Veränderungen auf histomorphologischer Ebene hinsichtlich des Auftretens renaler Fibrose, glomerulärer und tubulärer Schädigung, oder perivaskulärer Fibrose festgestellt werden. Lediglich die glomeruläre Filtrationsfunktion war ab dem 12. Immunisierungsmonat zunehmend beeinträchtigt, was sich an einer progredienten Proteinurie zeigte. Obwohl anti-β1-ECII-AK durchaus einen gewissen Effekt auf die Nierenfunktion haben, ist ihr Einfluss nicht stark genug um die Niere kritisch zu schädigen. Unterschiede zwischen immunisierten und Kontrolltieren, welche zu späteren Zeitpunkten (d.h. ab dem 12. Immunisierungsmonat) auftreten, sind wahrscheinlich sekundäre Effekte der progredienten Herzinsuffizienz, die die immunisierten Tiere im Verlauf des Experiments entwickeln. Unsere Studie ist die Erste, die sich mit den Effekten von stimulierenden anti-β1-AK auf die Niere und ihre Zusammenhänge mit der antikörper-induzierten Herzinsuffizienz (dem sogenannten kardio-renalen „Crosstalk“) befasst. Obwohl unsere Ergebnisse in einem Tiermodell erzielt wurden, könnten sie von großem Nutzen sein, um die Krankheitsentwicklung von anti-β1-Autoantikörper-positiven Patienten besser zu verstehen. Unseren Ergebnissen zufolge sollte die Behandlung von Autoimmun-DCM auf eine möglichst direkte und spezifische Neutralisierung/Eliminierung von anti-β1-Autoantikörpern abzielen und gleichzeitig alle kardio- und renal-protektiven Elemente der Standard-Therapie der Herzinsuffizienz (d.h. Gabe von ACE-Hemmern, AT1-Rezeptor-Inhibitoren und β-Blockern) einschließen. KW - Nierenfunktion KW - Beta-1-Rezeptor KW - kidney KW - Antikörper KW - beta1-adrenergic receptor KW - antibodies Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-106285 ER - TY - JOUR A1 - Krzymanski, M. A1 - Waaga, A. M. A1 - Ulrichs, Karin A1 - Müller-Ruchholtz, Wolfgang T1 - Long-standing rat kidney graft survival by a combination of organ perfusion with MHC class II monoclonal antibody and immunosuppression with reduced doses of 15-deoxyspergualin. N2 - No abstract available KW - Niere KW - Ratte KW - MHC Klasse II KW - kidney KW - rat Y1 - 1991 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-64442 ER - TY - JOUR A1 - Shepard, Blythe D. A1 - Cheval, Lydie A1 - Peterlin, Zita A1 - Firestein, Stuart A1 - Koepsell, Hermann A1 - Doucet, Alain A1 - Pluznick, Jennifer L. T1 - A Renal Olfactory Receptor Aids in Kidney Glucose Handling JF - Scientific Reports N2 - Olfactory receptors (ORs) are G protein-coupled receptors which serve important sensory functions beyond their role as odorant detectors in the olfactory epithelium. Here we describe a novel role for one of these ORs, Olfr1393, as a regulator of renal glucose handling. Olfr1393 is specifically expressed in the kidney proximal tubule, which is the site of renal glucose reabsorption. Olfr1393 knockout mice exhibit urinary glucose wasting and improved glucose tolerance, despite euglycemia and normal insulin levels. Consistent with this phenotype, Olfr1393 knockout mice have a significant decrease in luminal expression of Sglt1, a key renal glucose transporter, uncovering a novel regulatory pathway involving Olfr1393 and Sglt1. In addition, by utilizing a large scale screen of over 1400 chemicals we reveal the ligand profile of Olfr1393 for the first time, offering new insight into potential pathways of physiological regulation for this novel signaling pathway. KW - olfactory receptor KW - Olfr1393 KW - kidney KW - glucose handling Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-167605 VL - 6 IS - 35215 ER - TY - THES A1 - Sieber, Maximilian T1 - Evaluation of 1H-NMR and GC/MS-based metabonomics for the assessment of liver and kidney toxicity T1 - Bewertung von 1H-NMR und GC/MS-Metabonomics zur Erkennung von Leber- und Nierentoxizität N2 - For the assessment of metabonomics techniques for the early, non-invasive detection of toxicity, the nephrotoxins gentamicin (s.c. administration of 0, 60 and 120 mg/kg bw 2x daily for 8 days), ochratoxin A (p.o. administration of 0, 21, 70 and 210 µg/kg bw 5 days/week for 90 days) and aristolochic acid (p.o. administration of 0, 0.1, 1.0 and 10 mg/kg bw for 12 days) were administered to rats and urine samples were analyzed with 1H-NMR and GC/MS. Urine samples from the InnoMed PredTox project were analyzed as well, thereby focusing on 1H-NMR analysis and bile duct necrosis as histopathological endpoint. 1H-NMR analysis used water supression with the following protocol: 1 M phosphate buffer, D2O as shift lock reagent, D4-trimethylsilyl­propionic acid as chemical shift reference, noesygppr1d pulse sequence (Bruker). For multivariate data analysis, spectral intensity was binned into 0.04 ppm wide bins. GC/MS analysis of urine was carried out after protein precipitation with methanol, drying, derivatization with methoxyamine hydrochloride in pyridine and with methyl(trimethylsilyl)­trifluoroacetamide on a DB5-MS column using EI ionization. The chromatograms were prepared for multivariate data analysis using the R-program based peak picking and alignment software XCMS version 2.4.0. Principal component analysis (PCA) to detect and visualize time-point and dose-dependent differences between treated animals and controls and orthogonal projection to latent structures discriminant analysis (OPLS-DA) for identification of potential molecular markers of toxicity was carried out using SIMCA P+ 11.5 1H-NMR-based markers were identified and quantified with the Chenomx NMR Suite, GC/MS based markers were identified using the NIST Mass Spectral Database and by co-elution with authentic reference standards. PCA of urinary metabolite profiles was able to differentiate treated animals from controls at the same time as histopathology. An advantage over classical clinical chemistry parameters regarding sensitivity could be observed in some cases. Metabonomic analysis with GC/MS and 1H-NMR revealed alterations in the urinary profile of treated animals 1 day after start of treatment with gentamicin, correlating with changes in clinical chemistry parameters and histopathology. Decreased urinary excretion of citrate, 2-oxoglutarate, hippurate, trigonelline and 3-indoxylsulfate increased excretion of 5-oxoproline, lactate, alanine and glucose were observed. Ochratoxin A treatment caused decreased excretion of citrate, 2-oxoglutarate and hippurate and and increased excretion of glucose, myo-inositol, N,N-dimethylglycine, glycine, alanine and lactate as early as 2 weeks after start of treatment with 210µg OTA/kg bw, correlating with changes in clinical chemistry parameters and histopathology. Integration of histopathology scores increased confidence in the molecular markers discovered. Aristolochic acid treatment resulted in decreased urinary excretion of citrate, 2-oxoglutarate, hippurate and creatinine as well as increased excretion of 5-oxoproline, N,N-dimethylglycine, pseudouridine and uric acid. No alterations in clinical chemistry parameters or histopathology were noted.Decreased excretion of hippurate indicates alterations in the gut microflora, an effect that is expected as pharmacological action of the aminoglycoside antibiotic gentamicin and that can also be explained by the p.o. administration of xenobiotica. Decreased Krebs cycle intermediates (citrate and 2-oxoglutarate) and increased lactate is associated with altered energy metabolism. Increased pseudouridine excretion is associated with cell proliferation and was observed with aristolochic acid and ochratoxin A, for which proliferative processes were observed with histopathology. 5-oxoproline and N,N-dimethylglycine can be associated with oxidative stress. Glucose, a marker of renal damage in clinical chemistry, was observed for all three nephrotoxins studied. Single study analysis with PCA of GC/MS chromatograms and 1H-NMR spectra of urine from 3 studies conducted within the InnoMed PredTox project showing bile duct necrosis revealed alterations in urinary profiles with the onset of changes in clinical chemistry and histopathology. Alterations were mainly decreased Krebs cycle intermediates and changes in the aromatic gut flora metabolites, an effect that may result as a secondary effect from altered bile flow. In conclusion, metabonomics techniques are able to detect toxic lesions at the same time as histopathology and clinical chemistry. The metabolites found to be altered are common to most toxicities and are not organ-specific. A mechanistic link to the observed toxicity has to be established in order to avoid confounders such as body weight loss, pharmacological effects etc. For pattern recognition purposes, large databases are necessary. N2 - Zur Bewertung von Metabonomics-Techniken zur frühen, nicht-invasiven Erkennung von Toxizität wurde Rattenurin nach wiederholter Gabe von Nephrotoxinen mit 1H-NMR und GC/MS analysiert. Untersucht wurden Gentamicin (s.c.-Gabe von 0, 60 und 120 mg/kg Körpergewicht (KG) 2x tägl. über 8 Tage), Ochratoxin A (p.o.-Gabe von 0, 21, 70 und 210 µg/kg KG 5xl wöchentlich für 90 Tage) und Aristolochiasäure (p.o.-Gabe von 0, 0.1, 1.0 und 10 mg/kg KG über 12 Tage). Proben von 16 Studien des InnoMed PredTox Projekts wurden mit 1H-NMR auf den histopathologischen Endpunkt Gallengangnekrose (BDN) untersucht. Folgende Parameter wurden zur 1H-NMR-Analyse mit Wasserunterdrückung verwendet: 1 M Phosphatpuffer, shift lock Reagenz D2O und Referenzierung der chemischen Verschiebung auf D4-Trimethylsilyl­propionsäure, noesygppr1d-Pulssequenz (Bruker). Zur multivariaten Datenanalyse wurden die Spektren in 0.04 ppm große „bins“ unterteilt. Zur GC/MS-Analyse wurden nach Proteinfällung mit Methanol die Urinproben getrocknet und mit Methoxyaminhydrochlorid in Pyridin und Methyl(trimethylsilyl)trifluoracetamid derivatisiert und auf einer DB5-MS -Säule getrennt. Die GC/MS-Chromatogramme wurden mit dem R-Programm-basierten XCMS-Softwarepaket Version 2.4.0 zur multivariaten Datenanalyse vorbereitet. Hauptkomponentenanalyse (PCA) zur Visualisierung von zeit- und dosisabhängigen Unterschieden zwischen Kontrollen und behandelten Tieren und „orthogonal projection to latent structures“-Diskriminantenanalyse (OPLS-DA) zur Identifizierung von Toxizitätsmarkern erfolgte mit SIMCA P+11.5 Die Chenomx-NMR-Suite wurde zur Identifizierung und Quantifizierung von 1H NMR-basierten Markern verwendet; GC/MS-basierte Marker wurden mit der „NIST Mass Spectral Database“ und durch Koelution mit Referenzstandards identifiziert. PCA unterschied Kontroll- von behandelten Tieren zum gleichen Zeitpunkt wie Histopathologie. Gegenüber klinisch-chemischen Parametern war Metabonomics in einigen Fällen empfindlicher. Gentamicin induzierte nach Tag 1 erniedrigte Ausscheidung von Citrat, 2-Oxoglutarat, Hippurat, Trigonellin und 3-Indoxylsulfat Urin, sowie erhöhte Ausscheidung von Lactat, Alanin, 5-Oxoprolin und Glucose, begleitet von geringfügigen Änderungen in klinisch-chemischen Parametern. Ochratoxin A verursachte nach zwei Wochen in einzelnen Tieren eine erniedrigte Ausscheidung von Citrat, 2-Oxoglutarat und Hippurat sowie eine erhöhte Ausscheidung von Glucose, myo-Inositol, N,N-Dimethylglycin, 5-Oxoprolin, Glycin, Alanin und Lactat, korrelierend mit Veränderungen in klinisch-chemischen Parametern und in der Histopathologie. Verwendung von Histopathologiedaten in multivariaten Modellen zur Markeridentifizierung erhöhte die Konfidenz der Marker. Aristolochiasäure induzierte eine erniedrigte Ausscheidung von Citrat, 2-Oxoglutarat, Hippurat und Creatinin und eine erhöhte Ausscheidung von 5-Oxoprolin, N,N-Dimethylglycin und Pseudouridin, ohne Veränderung der klinisch-chemischen Parameter oder der Histopathologie. Erniedrigte Ausscheidung von Hippurat weist auf eine veränderte Darmmikroflora hin; für das Aminoglykosid-Antibiotikum Gentamicin ist dies ein pharmakologischer Effekt, der für die perorale Gabe von Xenobiotica zu erwarten ist. Erniedrigte Ausscheidung von Citrat und 2-Oxoglutarat und erhöhte Ausscheidung von Lactat zeigt einen veränderten Energiestoffwechsel. Erhöhte Ausscheidung von Pseudouridin ist mit Zell­proliferation assoziiert und wurde nach Gabe der Kanzerogene Ochratoxin A und Aristolochiasäure beobachtet, bei denen proliferative Prozesse in der Histopathologie gefunden wurden. 5-Oxoprolin und N,N-Dimethyl­glycin deuten auf erhöhten oxidativen Stress hin. Erhöhte Glucose im Urin, ein Parameter zur Diagnose von Nierenschäden in der klinischen Chemie, wurde in allen drei Studien mit Nephrotoxinen beobachtet. GC/MS- und 1H-NMR-Daten von InnoMed-Studien mit Gallengang­nekrosen als histopathologischen Endpunkt zeigten Veränderung im Urin zeitgleich mit klinisch-chemischen Parametern und Histopathologie; hauptsächlich erniedrigte Ausscheidung von Citratzyklusintermediaten und Veränderungen bei Darmflora-assoziierten Metaboliten, – ein Effekt, der wahrscheinlich veränderten Gallenfluss zurückzuführen ist. Metabonomics ist prinzipiell zum gleichen Zeitpunkt wie klinisch-chemische Parameter und Histopathologie zur Erkennung von toxischen Veränderungen geeignet. Die veränderten Metaboliten sind jedoch zumeist nicht organspezifisch und können mit allgemeinen Toxizitätsmechanismen, wie oxidativem Stress oder Zellproliferation, in Verbindung gebracht werden. Für die Bewertung der Ergebnisse von Metabonomics-Studien ist ein mechanistisches Verständnis der Veränderungen im Urinprofil notwendig, um eine Trennung von toxischen Effekten und solchen, die auf pharmakologische Wirkung, Körpergewichtsverlust etc. zurückzuführen sind, zu erreichen. Für eine Vorhersage von toxischen Mechanismen aufgrund der Urinprofile ist eine größere Datengrundlage notwendig. KW - Toxikologie KW - Protonen-NMR-Spektroskopie KW - GC-MS KW - Multivariate Analyse KW - Niere KW - Leber KW - Metabonomics KW - Toxicology KW - Metabonomics KW - GC/MS KW - 1H-NMR-Spectroscopy KW - multivariate analysis KW - kidney KW - liver Y1 - 2009 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-43052 ER - TY - JOUR A1 - Toyama, Yoshitaka A1 - Werner, Rudolf A. A1 - Ruiz-Bedoya, Camilo A. A1 - Ordonez, Alvaro A. A1 - Takase, Kei A1 - Lapa, Constantin A1 - Jain, Sanjay K. A1 - Pomper, Martin G. A1 - Rowe, Steven P. A1 - Higuchi, Takahiro T1 - Current and future perspectives on functional molecular imaging in nephro-urology: theranostics on the horizon JF - Theranostics N2 - In recent years, a paradigm shift from single-photon-emitting radionuclide radiotracers toward positron-emission tomography (PET) radiotracers has occurred in nuclear oncology. Although PET-based molecular imaging of the kidneys is still in its infancy, such a trend has emerged in the field of functional renal radionuclide imaging. Potentially allowing for precise and thorough evaluation of renal radiotracer urodynamics, PET radionuclide imaging has numerous advantages including precise anatomical co-registration with CT images and dynamic three-dimensional imaging capability. In addition, relative to scintigraphic approaches, PET can allow for significantly reduced scan time enabling high-throughput in a busy PET practice and further reduces radiation exposure, which may have a clinical impact in pediatric populations. In recent years, multiple renal PET radiotracers labeled with C-11, Ga-68, and F-18 have been utilized in clinical studies. Beyond providing a precise non-invasive read-out of renal function, such radiotracers may also be used to assess renal inflammation. This manuscript will provide an overview of renal molecular PET imaging and will highlight the transformation of conventional scintigraphy of the kidneys toward novel, high-resolution PET imaging for assessing renal function. In addition, future applications will be introduced, e.g. by transferring the concept of molecular image-guided diagnostics and therapy (theranostics) to the field of nephrology. KW - glomerular filtration rate KW - renal KW - kidney KW - renal function KW - positron emission tomography KW - nephrology KW - urology KW - molecular imaging KW - theranostics Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-260090 VL - 11 IS - 12 ER - TY - JOUR A1 - Weidemann, Frank A1 - Sanchez-Nino, Maria D. A1 - Politei, Juan A1 - Oliveira, João-Paulo A1 - Wanner, Christoph A1 - Warnock, David G. A1 - Oritz, Alberto T1 - Fibrosis: a key feature of Fabry disease with potential therapeutic implications JF - Orphanet Journal of Rare Diseases N2 - Fabry disease is a rare X-linked hereditary disease caused by mutations in the AGAL gene encoding the lysosomal enzyme alpha-galactosidase A. Enzyme replacement therapy (ERT) is the current cornerstone of Fabry disease management. Involvement of kidney, heart and the central nervous system shortens life span, and fibrosis of these organs is a hallmark of the disease. Fibrosis was initially thought to result from tissue ischemia secondary to endothelial accumulation of glycosphingolipids in the microvasculature. However, despite ready clearance of endothelial deposits, ERT is less effective in patients who have already developed fibrosis. Several potential explanations of this clinical observation may impact on the future management of Fabry disease. Alternative molecular pathways linking glycosphingolipids and fibrosis may be operative; tissue injury may recruit secondary molecular mediators of fibrosis that are unresponsive to ERT, or fibrosis may represent irreversible tissue injury that limits the therapeutic response to ERT. We provide an overview of Fabry disease, with a focus on the assessment of fibrosis, the clinical consequences of fibrosis, and recent advances in understanding the cellular and molecular mechanisms of fibrosis that may suggest novel therapeutic approaches to Fabry disease. KW - Fabry KW - fibrosis KW - podocyte KW - Lyso-Gb3 KW - kidney KW - enzyme replacement therapy KW - alpha-galactosidase-A KW - focal semental glomerulosclerosis KW - cardiovascular magnetic-resonance KW - left-ventricular hypertrophy KW - biopsy findings KW - agalsidase-beta KW - natural-history data KW - cardiac energy metabolism KW - randomized controlled trial Y1 - 2013 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-124773 SN - 1750-1172 VL - 8 IS - 116 ER - TY - JOUR A1 - Werner, Rudolf A. A1 - Ordonez, Alvaro A. A1 - Sanchez-Bautista, Julian A1 - Marcus, Charles A1 - Lapa, Constantin A1 - Rowe, Steven P. A1 - Pomper, Martin G. A1 - Leal, Jeffrey P. A1 - Lodge, Martin A. A1 - Javadi, Mehrbod S. A1 - Jain, Sanjay K. A1 - Higuchi, Takahiro T1 - Novel functional renal PET imaging with 18F-FDS in human subjects JF - Clinical Nuclear Medicine N2 - The novel PET probe 2-deoxy-2-18F-fluoro-D-sorbitol (18F-FDS) has demonstrated favorable renal kinetics in animals. We aimed to elucidate its imaging properties in two human volunteers. 18F-FDS was produced by a simple one-step reduction from 18F-FDG. On dynamic renal PET, the cortex was delineated and activity gradually transited in the parenchyma, followed by radiotracer excretion. No adverse effects were reported. Given the higher spatiotemporal resolution of PET relative to conventional scintigraphy, 18F-FDS PET offers a more thorough evaluation of human renal kinetics. Due to its simple production from 18F-FDG, 18F-FDS is virtually available at any PET facility with radiochemistry infrastructure. KW - 2-deoxy-2-18F-fluoro-D-sorbitol KW - Positronen-Emissions-Tomografie KW - 18F-FDS KW - renal imaging KW - Positron-Emission Tomography KW - split renal function KW - kidney Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-174634 SN - 0363-9762 VL - 44 IS - 5 ER -