Κατεύθυνση Φαρμακευτική Ανάλυση - Έλεγχος ποιότητας
Library of the School of Science

2017-10-18

2017

Ntzoumanika Varvara

Γκίκας Ευάγγελος, Επίκουρος Καθηγητής, Τμήμα Φαρμακευτικής, Σχολή Επιστημών Υγείας

Μεταβολομική Μελέτη του Συμπυκνώματος Εκπνεόμενου Αέρα για τη διάκριση του Άσθματος σε υποκατηγορίες, με τη χρήση Φασματοσκοπίας Πυρηνικού Μαγνητικού Συντονισμού (NMR) και Φασματομετρίας Μάζας (MS)

Greek

Metabolomic Analysis of Exhaled Breath Condensate for Asthma classification, using Nuclear Magnetic Resonance Spectroscopy (NMR) and Mass Spectrometry (MS)

Asthma is a chronic inflammatory disease of the lung airways, which is characterized by a usually reversible airway obstruction and bronchospasm. Asthma diagnosis is usually based on the patients’ history, response to therapy over time and spirometry. According to the frequency of symptoms, asthma is clinically classified as intermittent, mild persistent, moderate persistent and severe persistent.
Since the clinical classification of the disease is often difficult to accomplish, it is necessary to use experimental results based on analytical measurements, in order to evaluate asthma severity. A means to achieve this, is through the study of Exhaled Breath Condensate (EBC). EBC is the exhalate from breath that is condensed via cooling using a specialized collection device. EBC consists of water vapour and aerosolised particles mainly derived from the Airway Lining Fluid (ALF). It is a biological material that reflects the composition of the airway lining fluid, thus providing insight about the inflammatory state of the airways. Due to its consistency, EBC is often used for the detection of biomolecules which are representative of the pathophysiology of respiratory diseases, such as asthma.
In this study, patients with mild to moderate and severe asthma were subjected for at least six months to the same treatment for well controlled or partially controlled asthma. Patients with respiratory diseases other than asthma or other significant comorbidities which may be related to the present study were excluded. Furthermore, patients with an asthma exacerbation or an upper or lower respiratory tract infection in the last 2 months prior to the inclusion to this study were also excluded. The evaluation of the patients was performed on morning hours, where the patients had not digested any food or beverages and had abstained from smoking for at least 2 hours prior to EBC collection. Also, simple spirometry was performed and fractional exhaled nitric oxide (FeNO) was measured. Following their collection, the EBC samples were subsequently analyzed with UHPLC-HRMS (Orbitrap Discovery) and NMR spectroscopy (Bruker Avance III 600 MHz). Multivariate analysis was performed in order to determine the existence of any differentiations of the patients’ metabolic profile.
The results of the statistical analysis showed clear discrimination between the two groups for the UHPLC-MS results, while in the case of NMR spectroscopy no apparent discrimination among the samples was observed. In addition, new models were created from the UHPLC-MS data after the removal of the biological variation among the subjects, which does not show any appreciable effect to the discrimination. Particular interest lies in the PLS (Partial Least Squares) Regression models, which were created in an attempt to correlate the UHPLC-MS data with the spirometry values of FEV1 (Forced Expiratory Volume in 1 second) and FEV1/FVC ratio (also called Tiffeneau-Pinelli index) and the FeNO values. Promising results were obtained in the case of the correlation between the data derived from the positive ionization mode and the FEV1 values, where a noticeable discrimination and a high classification rate are noted among the samples.

asthma, exhaled breath condensate (EBC), mass spectrometry (MS), metabolomics, NMR spectroscopy

No

0

Yes

117

110

File access is restricted only to the intranet of UoA.

https://pergamos.lib.uoa.gr/uoa/dl/object/2037506