Department of Chemistry
Library of the School of Science

2023-12-08

2023

Barla Ioanna

Γκίκας Ευάγγελος, Καθηγητής, Τμήμα Χημείας, ΕΚΠΑ
Θωμαΐδης Νικόλαος, Καθηγητής, Τμήμα Χημείας, ΕΚΠΑ
Ντότσικας Ιωάννης, Αναπληρωτής Καθηγητής, Τμήμα Φαρμακευτικής, ΕΚΠΑ
Τσαρμπόπουλος Αντώνιος, Καθηγητής, Ιατρική Σχολή, ΕΚΠΑ
Παναγιώτου Γεώργιος, Ερευνητής Α, Διευθυντής και Πρόεδρος του Δ.Σ. του Ερευνητικού Ιδρύματος «ΑΛΕΞΑΝΔΡΟΣ ΦΛΕΜΙΝΓΚ»
Γκίκα Ελένη, Επίκουρη Καθηγήτρια, Τμήμα Ιατρικής, ΑΠΘ
Guro F. Giskeodegard, Associate Professor, Department of Public Health and Nursing, NTNU

Development of methodologies for the identification of biomarkers in clinical/ biological samples by high resolution mass spectrometry techniques

English

Development of methodologies for the identification of biomarkers in clinical/ biological samples by high resolution mass spectrometry techniques

The major goal of 21st century toxicology is to assess the efficiency/ toxicity of drugs before the step of clinical trials, and therefore focuses on the development of quick, versatile, and cheap methods that will enable the toxicity prediction during the in-vivo testing. The novel analytical methodologies and the emerging computational resources facilitate this effort. HRMS-based metabolomics present a particular interest in the terms of modern toxicology. The metabolites have universal structures and therefore, they facilitate the animal-to-human translation. Also, the metabolome is a consistent descriptor of the phenotype, so the metabolomics studies permit the deep comprehension of the biochemistry causes of toxicity and allow the creation of prediction models as well. Under this notion the current doctoral thesis focuses on the development of thorough metabolomics methodologies in the terms of the detection of toxicity related biomarkers.
The first part of this study (Chapters 4&5) presents the investigation of the nephrotoxicity caused by the administration of the antineoplastic drug Carfilzomib (Cfz). An in-vivo experiment was performed, using six mice that were treated with 8mg/kg Cfz (Cfz-group) and six mice that received normal saline (Control-group). The plasma, the kidneys and the urine were used for UPLC-HRMS-DIA-based metabolomics analysis. Multivariate and univariate chemometrics were implemented for the classification and the variable selection. In addition, library-free and library-based methods were used for metabolites identification. The study developed post-hoc analysis methods to investigate potential correlations between the metabolites and to highlight interaction between the Cfz-toxicity (phenotype) and the circulatory/ urinary system (biosample). The study showed that the Cfz has severe impact on the kidneys and disrupts the renal metabolism, inducing kidney injury. Several of the identified metabolites were related to uremic condition, oxidative stress, inflammation, and kidney impairment.
The second part of this study (Chapter 6) focused on the detection of early alterations of the metabolomic profiles of oncology children’s patients, that could explain/ predict the future expression of cardiotoxicity (CT), when they would undergo chemotherapy. In collaboration with the Department of Oncology and Hematology of the Children’s Hospital “Agia Sofia”, bloods samples of patients were collected before their submission to chemotherapy. The children followed the appropriate therapeutic protocol and some expressed acute cardiotoxicity. A UPLC-HRMS-DIA metabolomics analysis was performed in the blood samples, and the a posteriori knowledge of the CT expression was used to group the children in CT-Risk and No-Risk. The investigation focused on the variable selection procedure, combining 4 complementary statistical methods (KODAMA, OPLS-DA, BORUTA, t-test). The motivating idea was that if a variable exhibits good performance in more than three of these tests, then it has increased probability to be CT-related (Bayesian Probabilistic Theory). Moreover, the study set specific criteria for the confidence of DIA-identification. Finally, the study achieved the classification of CT-risk patients with models that showed acceptable figures of merit. Moreover, identified metabolites showed early alterations in the metabolic pathways that participate in the cardiac energy metabolism and suggested that the chemotherapy triggers preexisting cardiac function abnormalities, leading to acute CT events.
The last part of the study (Chapter 7) investigated the impact of the human doses of colistin (CMS) in mice, aiming to shed light on the biochemical reasons of CMS toxicity. CMS is a last resort antibiotic related with severe neuro and nephrotoxicity. Aiming to shed light on the impact of CMS in non-toxic conditions, in the current study, two doses of CMS, Low (1 mg/kg) and High (1.5 mg/kg) versus a control (normal saline), were administered to mice. Samples of plasma, kidney, and liver were analyzed with a UPLC-HRMS-DIA-based metabolomics workflow. The data were submitted to PLS-DA, PLS-R and ROC analysis. The results pointed out six dose-responding metabolites, renal dopamine dysregulation, and extended perturbations in renal purine metabolism. An intriguing finding was the increased formation of renal xanthine, which is an AChE activator, leading to rapid degradation of achetylcholine, suggesting an association of nephrotoxicity and neurotoxicity.

Science

metabolomics, High resolution mass spectrometry (HRMS), biomarkers, toxicology, chemometrics, variable selection, colistin, carfilzomib, children with malignancies, nephrotoxicity, cardiotoxicity, toxicity risk assessment

Yes

4

Yes

151

188

File access is restricted until 2025-06-11.

https://pergamos.lib.uoa.gr/uoa/dl/object/3371001