Institut für Pharmazie und Lebensmittelchemie
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Sonstige beteiligte Institutionen
- Universität Belgrad, Serbien (2)
- ACC GmbH Analytical Clinical Concepts (1)
- Apotheke, Universitätsklinikum Würzburg (1)
- Bayer AG, Research & Development, Pharmaceuticals, Investigational Toxicology (1)
- Bundesinstitut für Arzneimittel und Medizinprodukte (1)
- Friedrich-Schiller-Universität Jena (1)
- Helmholtz Institute for RNA-based Infection Biology (HIRI), Josef-Schneider-Straße 2/D15, DE-9708 Wuerzburg, Germany (1)
- Helmholtz Institute for RNA-based Infection Biology (HIRI), Josef-Schneider-Straße 2/D15, DE-97080 Wuerzburg, Germany (1)
- IBMP - Institut für Biomedizinische und Pharmazeutische Forschung in Nürnberg-Heroldsberg (1)
- Johns Hopkins School of Medicine (1)
EU-Project number / Contract (GA) number
- 26230120009 (1)
- 296679 (1)
- 314911 (1)
- 701983 (1)
The aim of this study was to determine the potential of some Ghanaian underutilized legumes in helping to reduce the problems of poverty, hunger and malnutrition among the vulnerable group of the Ghanaian population. The study looked into the functional properties, fat and fatty acid distribution, raffinose, sucrose, glucose, fructose, calcium, magnesium, sodium, potassium, iron, copper, manganese, zinc, cyanide and isoflavone contents of raw and processed seed flours of Cajanus cajan, Canavalia ensiformis, Canavalia gladiata, Mucuna pruriens, Parkia biglobosa, Phaseolus lunatus and Vigna subterranea. The parameters mentioned above were also determined for raw fruit flour of Dialium guineense. In addition to these, the study also looked into the crude protein and starch contents of the raw and processed seed flours of Canavalia gladiata, Parkia biglobosa and Vigna subterranea. The obtained results suggest that the legumes may have untapped potential, which may be exploited to help assist in reducing hunger, malnutrition and poverty in Ghana. Results of the functional properties reveal that the legumes may serve useful roles in various food products. For instance, velvet tamarind (Dialium guineense) flour may be useful in infant food formulations because of it high solubility and low bulk density. African Locust bean (Parkia biglobosa) flour had the highest fat content among the studied flours, recording a fat content of approximately 14%. It may therefore be economical to express the oil and use the oil as an edible oil or for industrial applications for products such as soaps, shampoos, paints, etc. This means the properties of the oil of African Locust bean flour need to be studied to know the uses of the oil. Unsaturated fatty acids in the cis configuration formed more than 50% of the fatty acids in all the legumes. This observation coupled with the low sodium content of all the legumes suggest that these legumes may be suitable for consumption to prevent cardiovascular diseases. The daily nutrient needs of individuals can be met by the consumption of the appropriate amounts of these legumes. For example, 375.25 g of processed velvet beans (Mucuna pruriens) flour may be able to meet the adequate intake (AI) of 350 mg/day magnesium for adult males.
Schimmelpilze können in Abhängigkeit des Immunstatus und der Vorerkrankungen betroffener Patienten unterschiedliche Krankheitsbilder wie Hypersensitivitäts-erkrankungen oder lebensbedrohliche invasive Infektionen hervorrufen. Da die Diagnosestellung dieser Erkrankungen mitunter komplex und insensitiv ist, sollten im Rahmen dieser Arbeit unterschiedliche Ansätze neuer diagnostischer Assays untersucht werden.
In den letzten Jahren wurden Assays entwickelt, die auf Basis durchflusszytometrisch quantifizierter Pilz-spezifischer T-Zellen aus peripherem Blut einen supportiven Biomarker zur Diagnostik invasiver Mykosen liefern könnten. Da die hierfür isolierten T-Zellen anfällig gegenüber präanalytischer Lagerzeiten und immunsuppressiver Medikation sind, wurden hier Protokolloptimierungen vorgenommen, um anhand eines Vollblut-basierten Assays mit zusätzlicher CD49d-Kostimulation diesen Limitationen entgegen zu wirken. In einer Studie an gesunden Probanden konnte dabei gezeigt werden, dass die Kombination der Durchflusszytometrie mit ausgewählten Zytokin-Messungen (IL-5, IL-10 und IL-17) zu einer verbesserten Erkennung vermehrt Schimmelpilz-exponierter Personen beitragen könnte. Neben Infektionen könnten dabei im umwelt- und arbeitsmedizinischen Kontext Polarisationen der T-Zell-Populationen detektiert werden, welche mit Sensibilisierungen und Hypersensitivität assoziiert werden.
Zusätzlich wurde ein in vitro Transwell® Alveolarmodell zur Simulation pulmonaler Pilzinfektionen für Erreger der Ordnung Mucorales adaptiert, durch Reproduktion wichtiger Merkmale der Pathogenese von Mucormykosen validiert, und für Untersuchungen der Immunpathologie und Erreger-Invasion verwendet. Das Modell wurde anschließend zur in vitro Evaluation von radioaktiv markiertem Amphotericin B mit 99mTc oder 68Ga als nuklearmedizinischen Tracer verwendet. Die untersuchten Schimmelpilze zeigten dabei eine zeit- und dosis-abhängige Aufnahme der Tracer, während bakteriell infizierte Proben nicht detektiert wurden. Die erhobenen Daten dokumentieren ein vielversprechendes Potenzial von Amphotericin B-basierten Tracer, das in zukünftigen in vivo Studien weiter evaluiert werden sollte.
Microbial, mammalian and plant cells produce and contain secondary metabolites, which typically are soluble in water to prevent cell damage by crystallization. The formation of ion pairs, e.g. with carboxylic acids or mineral acids, is a natural blueprint to keep basic metabolites in solution. It was aimed at showing whether the mostly large carboxylates form soluble protic ionic liquids (PILs) with basic natural products resulting in enhanced aqueous solubility. Furthermore, their supramolecular pattern in aqueous solution was studied. Thereby, naturally occurring carboxylic acids were identified being appropriate counterions for natural basic compounds and facilitate the formation of PILs with their beneficial characteristics, like improved dissolution rate and enhanced apparent solubility.
Bile solubilization plays a major role in the absorption of poorly water-soluble drugs. Excipients used in oral drug formulations impact bile-colloidal properties and their molecular interactions. Polymer-induced changes of bile colloids, e.g., by Eudragit E, reduced the flux of the bile interacting drug Perphenazine whereas bile non-interacting Metoprolol was not impacted. This study corroborates these in vitro findings in rats. Eudragit E significantly reduced systemic availability of Perphenazine but not Metoprolol compared to the oral administrations without polymer. This study confirms the necessity to carefully select polymers for bile interacting drugs whereas non-bile interacting drugs are more robust in terms of excipient choice for formulation. The perspective of bile interaction may introduce interesting biopharmaceutical leverage for better performing oral formulations of tomorrow.
Poorly water-soluble drugs frequently solubilize into bile colloids and this natural mechanism is key for efficient bioavailability. We tested the impact of pharmaceutical polymers on this solubilization interplay using proton nuclear magnetic resonance spectroscopy, dynamic light scattering, and by assessing the flux across model membranes. Eudragit E, Soluplus, and a therapeutically used model polymer, Colesevelam, impacted the bile-colloidal geometry and molecular interaction. These polymer-induced changes reduced the flux of poorly water-soluble and bile interacting drugs (Perphenazine, Imatinib) but did not impact the flux of bile non-interacting Metoprolol. Non-bile interacting polymers (Kollidon VA 64, HPMC-AS) neither impacted the flux of colloid-interacting nor colloid-non-interacting drugs. These insights into the drug substance/polymer/bile colloid interplay potentially point towards a practical optimization parameter steering formulations to efficient bile-solubilization by rational polymer selection.
Polymer-Biokonjugationen, vornehmlich mit dem Goldstandard PEG, führen zu einer verbesserten Pharmakokinetik, beeinflussen aber auch die konformative Stabilität von Proteinen. Bisherige Mutationsstudien, in denen überwiegend (Asn)PEG4 -Konjugate der Beta-faltblattstrukturreichen, humanen Pin 1 WW-Domäne untersucht wurden, postulieren auf einer Proteindesolvatation beruhende Stabilisierungsmechanismen: eine Stärkung intramolekularer Salzbrücken und NH-pi-Bindungen, sowie entropisch günstige Wasserverdrängungen um apolare Aminosäuren und Hydroxylgruppen. Ziel dieser Arbeit ist es, die Protein-Polymer-Dynamik auf molekularer Ebene zu charakterisieren, um damit rationale Ansätze zum Design neuer Biokonjugate voranzutreiben und mögliche PEG-Alternativen zu etablieren. Hierzu wurde eine Vielzahl an Deskriptoren mittels Molekulardynamik-Simulationen der WW-Konjugate gewonnen und mit publizierten Stabilitätsdaten in multivariaten Regressions- und logistischen Klassifikationsmodellen korreliert. Die gewonnenen QSPR-Modelle decken im Vergleich zu einer bereits publizierten, kristallstrukturbasierten Richtlinie einen größeren und strukturell vielfältigeren Datensatz an Konjugaten ab und zeigen gleichzeitig, auch für ein Konjugat der Src SH3-Domäne, eine deutlich verbesserte Leistung. Die Modelldeskriptoren beschreiben sowohl eine Modulation der Solvatation als auch Protein-Polymer-Interaktionen. Metadynamik-Simulationen zeigten zudem die Polymerdynamik während einer partiellen Proteinentfaltung auf. Mithilfe weiterer Simulationen von Konjugaten des alpha-helikalen Her2-Affibodys wurde die Dynamik von PEG und verschiedener Alternativen (LPG, PEtOx, PMeOx) systematisch studiert. PEG interagierte mit positiv geladenen Lysinen und Argininen in der Nähe hydrophober Aminosäuren. LPG zeigte zusätzliche Wechselwirkungen der Hydroxylgruppen mit Aspartaten und Glutamaten. POx-Polymere interagierten mit Phenylalaninen, Tyrosinen und über Carbonylgruppen mit HB-Donatoren. Größere Konjugate (10 - 50 kDa PEG/LPG/PEtOx) des antiviralen Biologikums Interferon-alpha2a wurden mittels gaußbeschleunigter MDs und einer CG-Simulation analysiert. Charakteristische Wechselwirkungspartner stimmten mit den Beobachtungen zu Oligomer-Konjugaten überein. In Einklang mit experimentellen Daten der Kooperationspartner zu den 10-kDa-Varianten deuteten zusätzliche Constrained-Network-Analysen, welche die Proteinflexibilität evaluieren, auf eine thermische Destabilisierung hin. Die Bioaktivität der untersuchten Konjugate wurde weiterhin erfolgreich mit den Gyrationsdurchmessern der modellierten Strukturen korreliert.
Exposure-efficacy and/or exposure-toxicity relationships have been identified for up to 80% of oral anticancer drugs (OADs). Usually, OADs are administered at fixed doses despite their high interindividual pharmacokinetic variability resulting in large differences in drug exposure. Consequently, a substantial proportion of patients receive a suboptimal dose. Therapeutic Drug Monitoring (TDM), i.e., dosing based on measured drug concentrations, may be used to improve treatment outcomes. The prospective, multicenter, non-interventional ON-TARGET study (DRKS00025325) aims to investigate the potential of routine TDM to reduce adverse drug reactions in renal cell carcinoma patients receiving axitinib or cabozantinib. Furthermore, the feasibility of using volumetric absorptive microsampling (VAMS), a minimally invasive and easy to handle blood sampling technique, for sample collection is examined. During routine visits, blood samples are collected and sent to bioanalytical laboratories. Venous and VAMS blood samples are collected in the first study phase to facilitate home-based capillary blood sampling in the second study phase. Within one week, the drug plasma concentrations are measured, interpreted, and reported back to the physician. Patients report their drug intake and toxicity using PRO-CTCAE-based questionnaires in dedicated diaries. Ultimately, the ON-TARGET study aims to develop a nationwide infrastructure for TDM for oral anticancer drugs.
Chimeric antigen receptors (CARs) are able to specifically direct T cells to tumor antigens and therapy with anti-CD19 CARs has already cured cancer patients with B-cell lymphomas who have undergone long-term therapy non-successful. Despite this impressive result, the therapy is currently only approved as a last treatment option for blood cancers due to its life-threatening deficiencies. For patient safety and to enable additional application such as the treatment of solid tumors, CAR-T cells must be controllable, e. g. by chemically programmable CARs (cpCARs) regulated by hapten-like compounds.
This thesis reports the synthesis and characterization of such hapten-like compounds. In the first step, seven different warheads with two different spacers were bound to biotin in order to find a suitable warhead for programming the cpCAR.
In a second step, synthetic routes for the three pharmacophores folate, c(RGD), and an RGD peptidomimetic were developed. The routes allow the modification of the pharmacophores with one of the warheads from the first step. CuAAC was chosen as a bioorthogonal approach to link pharmacophores and warheads.
In total, three different pharmacophores were modified with the 1,3-diketone motif of compound 21 leading to 112, 113 and 128. Activation of the T-cell signaling cascade was tested after binding of these hapten-like compounds to the cpCAR in the presence of suitable target structures. For 112, only a slight, non-significant, activation of the T-cell signaling cascade was observed, whereas for 113 and 128, a significant activation of the T-cell signaling cascade was observed.
The poor solubility of the folate compounds led to alternative strategies. Folic acid was exchanged by pteroic acid and the bifunctional, linear compounds were enlarged to trifunctional dendrimers.
Besides the reported regioisomer in 112, a second one, which was not reported to date, occurred by the cyclization of the linear RGD pentapeptide leading to 113.
After the reported synthesis of an RGD peptidomimetic analogous to 128 could not be reproduced, a new synthetic route was developed. It also consists of 17 steps, but reduces the number of linear steps from 13 to 10. Moreover, the developed route contains an asymmetric hydrogenation step and is, compared to the published one, more flexible by the use of the copper-catalyzed azide-alkyne cycloaddition (CuAAC). In addition, an unknown reaction was observed. Instead of the formation of a Schiff base in the reductive amination of 129, an insertion of propargylamine occurred forming 131. The reaction is almost quantitative and in high purity. After requiring no purification, it could be predestined for industrial purposes, such as the synthesis of N-functionalized 1,2-dihydroquinolines or as a building block with various orthogonal functional groups.
Besides the sulfonamide 16, the diketone (21, 27, 31) and lactam compounds (39 – 41), experiments on adapter molecules with further warheads were performed. In the synthesis of a proadapter approach, in which the warhead is formed only after the retro-aldol reaction catalyzed by the mAb, 6 of 10 steps were successfully performed. A newly developed synthesis to keto-sulfonyl and keto-sulfoxide compounds could not be completed but was performed on a small scale to the point of keto-sulfonyl and keto-sulfoxide. Furthermore, a universal synthesis route was designed to allow the introduction of the warhead at the end of the synthesis by acylation. Thus, after 5 shared steps, 3 of them in quantitative yield, different warheads may be introduced. Moreover, this also facilitates the purification and the analysis of the compounds by the absence of tautomerism or labile groups. However, the acylation experiments were not successful with either the acid cyanide or the Weinreb amide.
In summary, this thesis has proven that the 1,3-diketone motif is a suitable warhead for programming the cpCAR, which was developed by Hudecek et al. (unpublished data). The hapten-like compounds 112, 113 and 128 simultaneously bind to integrin ${\alpha}_v{\beta}_3$ and the cpCAR activating the T-cell signaling cascade. The modular synthesis strategy and the use of the bioorthogonal CuAAC allow straightforward access to these valuable immunotherapeutics but revealed the need for an additional purification step to remove copper ions.
Purpose
Knowledge on Ruxolitinib exposure in patients with graft versus host disease (GvHD) is scarce. The purpose of this prospective study was to analyze Ruxolitinib concentrations of GvHD patients and to investigate effects of CYP3A4 and CYP2C9 inhibitors and other covariates as well as concentration-dependent effects.
Methods
262 blood samples of 29 patients with acute or chronic GvHD who were administered Ruxolitinib during clinical routine were analyzed. A population pharmacokinetic model obtained from myelofibrosis patients was adapted to our population and was used to identify relevant pharmacokinetic properties and covariates on drug exposure. Relationships between Ruxolitinib exposure and adverse events were assessed.
Results
Median of individual mean trough serum concentrations was 39.9 ng/mL at 10 mg twice daily (IQR 27.1 ng/mL, range 5.6-99.8 ng/mL). Applying a population pharmacokinetic model revealed that concentrations in our cohort were significantly higher compared to myelofibrosis patients receiving the same daily dose (p < 0.001). Increased Ruxolitinib exposure was caused by a significant reduction in Ruxolitinib clearance by approximately 50%. Additional comedication with at least one strong CYP3A4 or CYP2C9 inhibitor led to a further reduction by 15% (p < 0.05). No other covariate affected pharmacokinetics significantly. Mean trough concentrations of patients requiring dose reduction related to adverse events were significantly elevated (p < 0.05).
Conclusion
Ruxolitinib exposure is increased in GvHD patients in comparison to myelofibrosis patients due to reduced clearance and comedication with CYP3A4 or CYP2C9 inhibitors. Elevated Ruxolitinib trough concentrations might be a surrogate for toxicity.
Breast cancer etiology is associated with both proliferation and DNA damage induced by estrogens. Breast cancer risk factors (BCRF) such as body mass index (BMI), smoking, and intake of estrogen-active drugs were recently shown to influence intratissue estrogen levels. Thus, the aim of the present study was to investigate the influence of BCRF on estrogen-induced proliferation and DNA damage in 41 well-characterized breast glandular tissues derived from women without breast cancer. Influence of intramammary estrogen levels and BCRF on estrogen receptor (ESR) activation, ESR-related proliferation (indicated by levels of marker transcripts), oxidative stress (indicated by levels of GCLC transcript and oxidative derivatives of cholesterol), and levels of transcripts encoding enzymes involved in estrogen biotransformation was identified by multiple linear regression models. Metabolic fluxes to adducts of estrogens with DNA (E-DNA) were assessed by a metabolic network model (MNM) which was validated by comparison of calculated fluxes with data on methoxylated and glucuronidated estrogens determined by GC- and UHPLC-MS/MS. Intratissue estrogen levels significantly influenced ESR activation and fluxes to E-DNA within the MNM. Likewise, all BCRF directly and/or indirectly influenced ESR activation, proliferation, and key flux constraints influencing E-DNA (i.e., levels of estrogens, CYP1B1, SULT1A1, SULT1A2, and GSTP1). However, no unambiguous total effect of BCRF on proliferation became apparent. Furthermore, BMI was the only BCRF to indeed influence fluxes to E-DNA (via congruent adverse influence on levels of estrogens, CYP1B1 and SULT1A2).