Evaluation of novel methodologies for the analysis of colistimethate sodium against Gram-negative bacteria

2021 ◽  
Author(s):  
Ιωάννα-Βαλεντίνη Δάγλα
Keyword(s):  
High Performance ◽  
High Resolution Mass Spectrometry ◽  
Similarity Index ◽  
Principal Component ◽  
Structural Similarity ◽  
Least Squares Regression ◽  
Colistimethate Sodium ◽  
C 50

Η κολιστίνη (πολυμυξίνη Ε) είναι ένα αντιβιοτικό που αποτελείται κυρίως από τις μορφές Α και Β και παράγεται από το βακτήριο Bacillus polymyxa var. colistinus. Απομονώθηκε για πρώτη από το βακτήριο το 1949 και αργότερα χορηγήθηκε ως μεθανοσουλφονική κολιστίνη (colistimethate sodium - CMS) για την αντιμετώπιση των Gram-αρνητικών βακτηρίων. Η χρήση της, όμως, περιορίστηκε τη δεκαετία του ’80 λόγω της νευροτοξικότητας και της νεφροτοξικότητας που προκαλούσε. Λόγω της εμφάνισης πολυανθεκτικών Gram-αρνητικών βακτηριών τις τελευταίες δύο δεκαετίες, η κολιστίνη άρχισε να χρησιμοποιείται ξανά ως αντιβιοτικό τελευταίας εκλογής, όταν όλες οι θεραπείες με άλλα αντιβιοτικά έχουν αποτύχει, καθώς αντιμετωπίζει αποτελεσματικά τις λοιμώξεις που οφείλονται σε αυτά τα βακτήρια. Η κολιστίνη χορηγείται παρεντερικά ως CMS που αποτελεί το ανενεργό και λιγότερο τοξικό προφάρμακο της κολιστίνης, το οποίο υδρολύεται στον οργανισμό (in vivo) δίνοντας την ενεργή μορφή (κολιστίνη). Η CMS παράγεται κατόπιν σουλφομεθυλίωσης των ελεύθερων αμινομάδων που υπάρχουν στο μόριο της κολιστίνης. Ωστόσο, η δομή της παραμένει μέχρι σήμερα ασαφής, καθώς δεν έχει εξακριβωθεί ο βαθμός της σουλφομεθυλίωσης των αμινομάδων. Είναι όμως γενικά αποδεκτό πως η CMS αποτελεί ένα πολύπλοκο μίγμα πολλών μορίων με διαφορετικό βαθμό υποκατάστασης. Η κολιστίνη αν και έχει ανακαλυφθεί εδώ και αρκετά χρόνια, δεν έχει υποβληθεί στις διαδικασίες ανάπτυξης φαρμάκων και έγκρισης που εφαρμόζονται σήμερα. Μέχρι σήμερα, οι έλεγχοι ποιότητας που εφαρμόζονται στα σκευάσματα της CMS βασίζονται σε μικροβιολογικές δοκιμασίες.Έχει παρατηρηθεί όμως πως, αν και τα φαρμακευτικά σκευάσματα της CMS ελέγχονται με μικροβιολογικές δοκιμασίες (in vitro), οδηγούν σε διαφορετικά επίπεδα ενεργής κολιστίνης στον οργανισμό (in vivo), τονίζοντας την ανάγκη για ανάπτυξη άλλων μεθόδων ποιοτικού ελέγχου των σκευασμάτων της CMS, ώστε να ελέγχεται με μεγαλύτερη ακρίβεια η σύσταση των φαρμακευτικών σκευασμάτων και κατ’ επέκταση η βιοδιαθεσιμότητά τους. Σκοπός της παρούσας διδακτορικής διατριβής είναι η ανάπτυξη αναλυτικής μεθόδου που είναι βασισμένη στην υγρoχρωματογραφία υπερυψηλής απόδοσης (ultra-high performance liquid chromatography – UPLC) συζευγμένη με φασματομετρία μάζας υψηλής διακριτικής ικανότητας (high resolution mass spectrometry – HRMS), για την μέτρηση της CMS σε σκευάσματα. Η μέθοδος αυτή θα μπορούσε να χρησιμοποιηθεί ως μέθοδος ποιοτικού ελέγχου των φαρμακευτικών σκευασμάτων της CMS. Αρχικά, λόγω της πολυπλοκότητας της CMS, κρίθηκε αναγκαίος ο πειραματικός σχεδιασμός για την βελτιστοποίηση των παραμέτρων τόσο της υγροχρωματογραφίας όσο και της φασματομετρίας μάζας. Ο πειραματικός σχεδιασμός περιλαμβάνει δύο στάδια στοχεύοντας τον διαχωρισμό των συστατικών της CMS. Τελικά, το χρωματογράφημα που προέκυψε αποκάλυψε 20 συστατικά. Ο διαχωρισμός επιτεύχθηκε χρησιμοποιώντας τη στήλη Waters Acquity BEH C8 και βαθμιδωτή έκλουση. Η κινητή φάση αποτελούνταν από A) υδατικό διάλυμα φορμικού αμμωνίου (0,005 Μ, pH=6) και Β) μίγμα μεθανόλης και ακετονιτριλίου (79/21 v/v). Πειραματικός σχεδιασμός πραγματοποιήθηκε και για τις παραμέτρους της φασματομετρίας μάζας, ώστε να επιτευχθεί η μέγιστη ευαισθησία. Για την ανάλυση, επιλέχθηκαν τα μονοφορτισμένα ιόντα των μορίων της CMS που προέκυψαν κατόπιν θετικού ιονισμού. Οι καμπύλες αναφοράς είχαν εύρος 50-110 μg/mL, που αντιστοιχεί στο 80-120% της ονομαστικής ποσότητας της CMS στα εμπορικά σκευάσματα. Λόγω της πολυπλοκότητας των χρωματογραφημάτων της CMS, αλλά και του φάσματος κάθε χρωματογραφικής κορυφής, εφαρμόστηκαν τεχνικές στοχευμένης (targeted) και μη στοχευμένης (untargeted) ανάλυσης χρησιμοποιώντας το λογισμικό MZmine. Εκτός από την κλασική μονοπαραμετρική στατιστική ανάλυση, χρησιμοποιήθηκε ακόμα το μοντέλο της παλινδρόμησης μερικών ελαχίστων τετραγώνων (partial least squares regression – PLSR), καθώς οι μεταβλητές ήταν περισσότερες από τις παρατηρήσεις. Η μεθοδολογία που αναπτύχθηκε χρησιμοποιήθηκε για την ανάλυση παρτίδων της CMS και βρέθηκαν διαφορές στη σύστασή τους. Επιπλέον, αναπτύχθηκε μεθοδολογία βασισμένη στην υγρoχρωματογραφία συζευγμένη με ανιχνευτή υπεριώδους (ultraviolet – UV) για την μέτρηση της CMS σε ενέσιμα σκευάσματα. Στην μεθοδολογία αυτή χρησιμοποιήθηκαν λογισμικά τα οποία είναι διαθέσιμα δωρεάν προκειμένου με ευκολία θα υιοθετηθεί από τις φαρμακευτικές εταιρείες αλλά και από την ερευνητική κοινότητα γενικότερα, ως μέθοδος ποιοτικού ελέγχου. Για τη βελτιστοποίηση των παραμέτρων της χρωματογραφίας χρησιμοποιήθηκε πειραματικός σχεδιασμός. Ο χρωματογραφικός διαχωρισμός των συστατικών της CMS επιτεύχθηκε με τη στήλη Waters Acquity BEH C8 και βαθμιδωτή έκλουση. Η κινητή φάση αποτελούνταν από Α) υδατικό διάλυμα φορμικού αμμωνίου (0,001 Μ) και Β) μίγμα μεθανόλης/ακετονιτριλίου (79/21 v/v). Τα μόρια της CMS ανιχνεύθηκαν στο μήκος κύματος 214 nm. Κατασκευάστηκαν 23 μονοπαραμετρικά μοντέλα γραμμικής παλινδρόμησης για την μέτρηση του κάθε συστατικού της CMS χωριστά και ένα μοντέλο PLSR για την εκτίμηση της συνολικής ποσότητας της CMS στα ενέσιμα σκευάσματα. Η μέθοδος επικυρώθηκε για το εύρος συγκεντρώσεων 110-220 μg/mL. Η μεθοδολογία που αναπτύχθηκε χρησιμοποιήθηκε για την ανάλυση παρτίδων της CMS. Οι παρτίδες συγκρίθηκαν ως προς μια παρτίδα αναφοράς με επιπλέον στατιστικές αναλύσεις, όπως ανάλυση κύριων συνιστωσών (principal component analysis – PCA), μέτρα ομοιότητας, χάρτες θερμότητας (heatmaps) και τον δείκτη δομικής ομοιότητας (structural similarity index).Η μέτρηση των επιπέδων της CMS στα βιολογικά υλικά των ασθενών είναι πολύ σημαντική προκειμένου να βρεθεί το κατάλληλο δοσολογικό σχήμα που θα περιορίζει την τοξικότητά της. Μέχρι σήμερα, η μέτρηση της CMS γίνεται με έμμεσο τρόπο, δηλαδή μετά από την όξινη υδρόλυσή της σε κολιστίνη. Στην παρούσα διατριβή, σκοπός είναι να βρεθούν οι συνθήκες που οδηγούν σε πλήρη υδρόλυση της CMS. Η αντίδραση μελετήθηκε σε επιταχυνόμενες συνθήκες: 40°C, 50°C και 60°C και τα αποτελέσματα εκτιμήθηκαν με τη χρήση της εξίσωσης του Arrhenius και το λογισμικό Tenua. Για τη μέτρηση της CMS και της κολιστίνης αναπτύχθηκε και επικυρώθηκε μέθοδος βασισμένη στην υγροχρωματογραφία υπερυψηλής απόδοσης συζευγμένης με φασματόμετρο μάζας με υβριδικό αναλυτή τετραπόλου – χρόνου πτήσης ιόντων (hybrid quadrupole time-of-flight – QqTOF). Με την παρούσα μεθοδολογία επιτεύχθηκε πλήρης υδρόλυση της CMS, σε αντίθεση με τις μεθοδολογίες που αναφέρονται στην βιβλιογραφία που, όπως αποδείχθηκε, οδηγούσαν σε μερική υδρόλυση. Αν και η χορήγηση της CMS αυξάνεται ραγδαία, η δομή της παραμένει ασαφής. Στην παρούσα διδακτορική διατριβή, έγιναν προσπάθειες αποσαφήνισης της δομής της CMS με τη χρήση της φασμοτομετρίας μάζας. Συγκεκριμένα, χρησιμοποιήθηκαν τέσσερις αναλυτές μάζας: 1) QqTOF, 2) LTQ Orbitrap Discovery XL, 3) Q-Exactive Orbitrap and 4) Omnitrap. Η έγχυση (infusion) της CMS στον αναλυτή μάζας πραγματοποιήθηκε εφαρμόζοντας διαφορετικές συνθήκες ως προς τον διαλύτη αραίωσης, το pH και τη θερμοκρασία αποδιαλύτωσης. Στους αναλυτές μάζας QqTOF και Omnitrap πραγματοποιήθηκαν επίσης πειράματα θραυσματοποίησης (MS/MS) και για την ερμηνεία τους χρησιμοποιήθηκε το λογισμικό Cyclobranch. Τελικά, βρέθηκαν οι δομές τριών συστατικών της CMS.

scholarly journals A Novel Validated Injectable Colistimethate Sodium Analysis Combining Advanced Chemometrics and Design of Experiments

Molecules ◽  
2021 ◽  
Vol 26 (6) ◽  
pp. 1546
Author(s):  
Ioanna Dagla ◽  
Anthony Tsarbopoulos ◽  
Evagelos Gikas
Keyword(s):  
Design Of Experiments ◽  
High Performance ◽  
Similarity Index ◽  
Principal Component ◽  
Partial Least Square ◽  
Least Square ◽  
Partial Least Square Regression ◽  
Distance Measures ◽  
Linear Regression Models ◽  
Colistimethate Sodium

Colistimethate sodium (CMS) is widely administrated for the treatment of life-threatening infections caused by multidrug-resistant Gram-negative bacteria. Until now, the quality control of CMS formulations has been based on microbiological assays. Herein, an ultra-high-performance liquid chromatography coupled to ultraviolet detector methodology was developed for the quantitation of CMS in injectable formulations. The design of experiments was performed for the optimization of the chromatographic parameters. The chromatographic separation was achieved using a Waters Acquity BEH C8 column employing gradient elution with a mobile phase consisting of (A) 0.001 M aq. ammonium formate and (B) methanol/acetonitrile 79/21 (v/v). CMS compounds were detected at 214 nm. In all, 23 univariate linear-regression models were constructed to measure CMS compounds separately, and one partial least-square regression (PLSr) model constructed to assess the total CMS amount in formulations. The method was validated over the range 100–220 μg mL−1. The developed methodology was employed to analyze several batches of CMS injectable formulations that were also compared against a reference batch employing a Principal Component Analysis, similarity and distance measures, heatmaps and the structural similarity index. The methodology was based on freely available software in order to be readily available for the pharmaceutical industry.

scholarly journals Phytochemical Study and In Vitro Screening Focusing on the Anti-Aging Features of Various Plants of the Greek Flora

Antioxidants ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 1206
Author(s):  
Aimilia D. Sklirou ◽  
Maria T. Angelopoulou ◽  
Aikaterini Argyropoulou ◽  
Eliza Chaita ◽  
Vasiliki Ioanna Boka ◽  
...  
Keyword(s):  
Plant Species ◽  
High Performance ◽  
High Resolution Mass Spectrometry ◽  
Ultra Performance Liquid Chromatography ◽  
Skin Aging ◽  
Rosa Damascena ◽  
Phytochemical Study ◽  
Age Related

Skin health is heavily affected by ultraviolet irradiation from the sun. In addition, senile skin is characterized by major changes in the collagen, elastin and in the hyaluronan content. Natural products (NPs) have been shown to delay cellular senescence or in vivo aging by regulating age-related signaling pathways. Moreover, NPs are a preferable source of photoprotective agents and have been proven to be useful against the undesirable skin hyperpigmentation. Greek flora harvests great plant diversity with approximately 6000 plant species, as it has a wealth of NPs. Here, we report an extensive screening among hundreds of plant species. More than 440 plant species and subspecies were selected and evaluated. The extracts were screened for their antioxidant and anti-melanogenic properties, while the most promising were further subjected to various in vitro and cell-based assays related to skin aging. In parallel, their chemical profile was analyzed with High-Performance Thin-Layer Chromatography (HPTLC) and/or Ultra-Performance Liquid Chromatography High-Resolution Mass Spectrometry (UPLC-HRMS). A variety of extracts were identified that can be of great value for the cosmetic industry, since they combine antioxidant, photoprotective, anti-melanogenic and anti-aging properties. In particular, the methanolic extracts of Sideritis scardica and Rosa damascena could be worthy of further attention, since they showed interesting chemical profiles and promising properties against specific targets involved in skin aging.

scholarly journals Antiplasmodial profile of selected compounds from Malaria Box: in vitro evaluation, speed of action and drug combination studies

2019 ◽  
Vol 18 (1) ◽  
Author(s):  
Guilherme Eduardo de Souza ◽  
Renata Vieira Bueno ◽  
Juliana Oliveira de Souza ◽  
Camila Lima Zanini ◽  
Fábio Cardoso Cruz ◽  
...  
Keyword(s):  
Combination Therapy ◽  
Inhibitory Activity ◽  
Similarity Index ◽  
Structural Similarity ◽  
Neutral Red ◽  
Molecular Target ◽  
Benzodiazepine Derivatives ◽  
Malaria Box

Abstract Background Artemisinin-based combination therapy (ACT) is used as the first-line treatment of uncomplicated malaria caused by the Plasmodium falciparum parasite and chloroquine-resistant Plasmodium vivax parasites. Evidence of resistance to ACT has been reported in Cambodia, and without new and effective anti-malarial agents, malaria burden and mortality will rise. Methods The used MolPrint 2D fingerprints and the Tanimoto similarity index were used to perform a structural similarity search within the Malaria Box collection to select diverse molecular scaffolds that are different from artesunate. Next, the inhibitory potency against the P. falciparum 3D7 strain (SYBR Green I inhibition assay) and the cytotoxicity against HepG2 cells (MTT and neutral red assays) were evaluated. Then, the speed of action, the combination profile of selected inhibitors with artesunate, and the P. berghei in vivo activity of the best compounds were assessed. Results A set of 11 structurally diverse compounds from the Malaria Box with a similarity threshold of less than 0.05 was selected and compared with artesunate. The in vitro inhibitory activity of each compound confirmed the reported potencies (IC50 values ranging from 0.005 to 1 µM). The cytotoxicity of each selected compound was evaluated and used to calculate the selectivity index (SI values ranging from 15.1 to 6100). Next, both the speed of action and the combination profile of each compound with artesunate was assessed. Acridine, thiazolopyrimidine, quinoxaline, benzimidazole, thiophene, benzodiazepine, isoxazole and pyrimidoindole derivatives showed fast in vitro inhibitory activity of parasite growth, whereas hydrazinobenzimidazole, indenopyridazinone and naphthalenone derivatives were slow-acting in vitro inhibitors. Combinatory profile evaluation indicated that thiazolopyrimidinone and benzodiazepine derivatives have an additive profile, suggesting that the combination of these inhibitors with artesunate is favourable for in vitro inhibitory activity. The remaining compounds showed an antagonistic combinatory profile with artesunate. The collected data indicated that the indenopyridazinone derivative, a bc1 complex inhibitor, had a similar association profile in combination with proguanil when compared to atovaquone combined with proguanil, thereby corroborating the correlation between the molecular target and the combination profile. Lastly, the in vivo activity of the thiazolopyrimidinone and benzodiazepine derivatives were assessed. Both compounds showed oral efficacy at 50 mg/kg in a mouse model of Plasmodium berghei malaria (64% and 40% reduction in parasitaemia on day 5 post-infection, respectively). Conclusions The findings in this paper shed light on the relationship among the speed of action, molecular target and combinatory profile and identified new hits with in vivo activity as candidates for anti-malarial combination therapy.

Hepatoprotective activity of a purified methanol extract and saponins from the roots of Chenopodium bonus-henricus L.

2019 ◽  
Vol 74 (11-12) ◽  
pp. 329-337 ◽  
Author(s):  
Zlatina Kokanova-Nedialkova ◽  
Paraskev Nedialkov ◽  
Magdalena Kondeva-Burdina ◽  
Rumyana Simeonova
Keyword(s):  
High Performance ◽  
High Resolution Mass Spectrometry ◽  
Antioxidant Activities ◽  
Rat Hepatocytes ◽  
Hepatoprotective Activity ◽  
Cellular Damage ◽  
Medicagenic Acid ◽  
Hepatoprotective Agents

Abstract An ultra-high-performance liquid chromatography-high-resolution mass spectrometry based profiling of a purified MeOH extract (PME) from the roots of Chenopodium bonus-henricus L. (Amaranthaceae) tentatively identified 15 saponins of six sapogenins. The PME exerts hepatoprotective and antioxidant activities comparable to those of flavonoid complex silymarin in in vitro (1 and 10 μg/mL) and in vivo (200 mg/kg/daily for 7 days) models of hepatotoxicity, induced by CCl4. The main constituents of PME, respectively saponins bonushenricoside A (1), 3-O-β-D-glucuronopyranosyl-bayogenin-28-O-β-D-glucopyranosyl ester (2), 3-O-β-D-glucuronopyranosyl-medicagenic acid-28-O-β-D-xylopyranosyl (1→4)-α-L-rhamnopyranosyl(1→2)-α-L-arabinopyranosyl ester (3), 3-O-β-D-glucuronopyranosyl-2β-hydroxygypsogenin-28-O-β-D-glucopyranosyl ester (4), 3-O-α-L-rabinopyranosyl-bayogenin-28-O-β-D-glucopyranosyl ester (6) and bonushenricoside B (8) (3 μg/mL each), compared to silymarin (5 and 50 μg/mL), significantly reduced the cellular damage caused by CCl4 in rat hepatocytes, preserved cell viability and glutathione level, decreased lactate dehydrogenase leakage and reduced lipid damage. The experimental data suggest that the glycosides of phytolaccagenin, bayogenin, medicagenic acid, 2β-hydroxygypsogenin, 2β-hydroxyoleanoic acid and oleanoic acid are a promising and safe class of hepatoprotective agents.

scholarly journals Mapping the lipid metabolites in follicular fluid from patients with infertility issues across ages

2020 ◽  
Author(s):  
Xingxing Zhang ◽  
Tianqi Wang ◽  
Jingyan Song ◽  
Jifeng Deng ◽  
Zhengao Sun
Keyword(s):  
Follicular Fluid ◽  
High Performance ◽  
High Resolution Mass Spectrometry ◽  
Age Groups ◽  
Follicular Development ◽  
Principal Component ◽  
Scientific Basis ◽  
Vitro Fertilization ◽  
Lipid Metabolites

Abstract Background: Follicular fluid is an important external environment for the growth and development of oocytes. A thorough identification of specific components in follicular fluid can better the existing understand of intracellular signal transduction and reveal potential biomarkers of oocyte health in women undergoing assisted reproductive therapy. To study the biomarkers that affect the development of oocytes, we have adopted a new method of SWATH to MRM( the sequential window acquisition of all theoretical fragment-ion spectra to multiple reaction monitor)metabolomics to provide extensive coverage and excellent quantitative data. This was done to investigate the differences in follicular fluid of patients undergoing in vitro fertilization (IVF) and embryo transfer in different age groups and to further explore the relationship between follicular fluid, age and reproductive function.Method: A combination of Ultra-high-performance liquid chromatography and high resolution mass spectrometry techniques were used to analyze the follicular fluid of 230 patients enrolled for the IVF cycle. The patients were of different ages grouped into two groups:the younger and older patients.The obtained multidimensional chromatographic data were processed by principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA). The charge ratios and mass numbers enabled for the identification of different fragments in the samples. Matching information obtained through database search and the fragment information obtained by fragment ion scan structurally identified substances in the samples. This was used to determine the differential compounds.Results: The quality and quantity of oocytes decline with age. This in caused by changes in follicular fluid metabolites. The main differences were in lipid metabolites. Some were up-regulated : Arachidonate, LysoPC(16:1), LysoPC(20:4) and LysoPC(20:3) while others were down-regulated: LysoPC(18:3) and LysoPC(18:1).Conclusions: Metabolomic analysis of follicular fluid revealed that with the increase in age, several differential metabolites are at play. Among these metabolites, lipid metabolism undergoes significant changes that affect the development of oocytes thus causing reduced fertility in older women. These differential metabolites related to follicular development may provide possible detection and treatment targets for promoting oocyte health, and provide scientific basis for understanding the environment of oocyte development.

scholarly journals A Cup of Hemp Coffee by Moka Pot from Southern Italy: An UHPLC-HRMS Investigation

Foods ◽  
2020 ◽  
Vol 9 (8) ◽  
pp. 1123
Author(s):  
Simona Piccolella ◽  
Giuseppina Crescente ◽  
Marialuisa Formato ◽  
Severina Pacifico
Keyword(s):  
High Performance ◽  
High Resolution Mass Spectrometry ◽  
Economic Problem ◽  
Added Value ◽  
Industrial Sectors ◽  
Current Maximum ◽  
Solid Liquid ◽  
Industrial Hemp

After a long period defined by prohibition of hemp production, this crop has been recently re-evaluated in various industrial sectors. Until now, inflorescences have been considered a processing by-product, not useful for the food industry, and their disposal also represents an economic problem for farmers. The objects of the present work are coffee blends enriched with shredded inflorescences of different cultivars of industrial hemp that underwent solid/liquid extraction into the Italian “moka” coffee maker. The obtained coffee drinks were analyzed by Ultra-High-Performance Liquid Chromatography-High Resolution Mass Spectrometry (UHPLC-HRMS) tools for their quali-quantitative phytocannabinoid profiles. The results showed that they are minor constituents compared to chlorogenic acids and caffeine in all samples. In particular, cannabidiolic acid was the most abundant among phytocannabinoids, followed by tetrahydrocannabinolic acid. Neither Δ9-tetrahydrocannabinol (THC) nor cannabinol, its main oxidation product, were detected. The percentage of total THC never exceeded 0.04%, corresponding to 0.4 mg/kg, far below the current maximum limits imposed by the Italian Ministry of Health. This study opens up a new concrete possibility to exploit hemp processing by-products in order to obtain drinks with high added value and paves the way for further in vitro and in vivo investigations aimed at promoting their benefits for human health.

scholarly journals Implication of Opioid Receptors in the Antihypertensive Effect of a Novel Chicken Foot-Derived Peptide

Biomolecules ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 992
Author(s):  
Anna Mas-Capdevila ◽  
Lisard Iglesias-Carres ◽  
Anna Arola-Arnal ◽  
Gerard Aragonès ◽  
Begoña Muguerza ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
Opioid Receptors ◽  
High Performance ◽  
Antihypertensive Effect ◽  
High Resolution Mass Spectrometry ◽  
Liquid Chromatography Tandem Mass

The peptide AVFQHNCQE demonstrated to produce nitric oxide-mediated antihypertensive effect. This study investigates the bioavailability and the opioid-like activity of this peptide after its oral administration. For this purpose, in silico and in vitro approaches were used to study the peptide susceptibility to GI digestion. In addition, AVFQHNCQE absorption was studied both in vitro by using Caco-2 cell monolayers and in vivo evaluating peptide presence in plasma from Wistar rats by ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) and by ultra-high performance liquid chromatography-high resolution mass spectrometry (UHPLC-HRMS). Both in vivo and in vitro experiments demonstrated that peptide AVFQHNCQE was not absorbed. Thus, the potential involvement of opioid receptors in the BP-lowering effect of AVFQHNCQE was studied in the presence of opioid receptors-antagonist Naloxone. No changes in blood pressure were recorded in rats administered Naloxone, demonstrating that AVFQHNCQE antihypertensive effect is mediated through its interaction with opioid receptors. AVFQHNCQE opioid-like activity would clarify the antihypertensive properties of AVFQHNCQE despite its lack of absorption.

scholarly journals Study on follicular fluid metabolomics components at different ages based on lipid metabolism

2020 ◽  
Author(s):  
xingxing zhang ◽  
tianqi wang ◽  
jingyan song ◽  
jifeng deng ◽  
Zhengao Sun
Keyword(s):  
Lipid Metabolism ◽  
Follicular Fluid ◽  
High Performance ◽  
High Resolution Mass Spectrometry ◽  
Age Groups ◽  
Principal Component ◽  
Vitro Fertilization ◽  
Different Ages

Abstract Background: Follicular fluid is an important external environment for the growth and development of oocytes. A thorough identification of specific components in follicular fluid can better the existing understand of intracellular signal transduction and reveal potential biomarkers of oocyte health in women undergoing assisted reproductive therapy. To study on follicular fluid metabolomics components at different ages based on lipid metabolism, we have adopted a new method of SWATH to MRM( the sequential window acquisition of all theoretical fragment-ion spectra to multiple reaction monitor)metabolomics to provide extensive coverage and excellent quantitative data. This was done to investigate the differences in follicular fluid of patients undergoing in vitro fertilization (IVF) and embryo transfer in different age groups and to further explore the relationship between follicular fluid, age and reproductive function.Method: A combination of Ultra-high-performance liquid chromatography and high resolution mass spectrometry techniques were used to analyze the follicular fluid of 230 patients enrolled for the IVF cycle. The patients were of different ages grouped into two groups:the younger and older patients.The obtained multidimensional chromatographic data were processed by principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA). The charge ratios and mass numbers enabled for the identification of different fragments in the samples. Matching information obtained through database search and the fragment information obtained by fragment ion scan structurally identified substances in the samples. This was used to determine the differential compounds.Results:The quality of oocytes decline with age,and the lipid composition in follicular fluid also changes,The lipid metabolism that changes with age may be related to the quality of oocytes.The main differences were in lipid metabolites. Some were up-regulated : Arachidonate, LysoPC(16:1), LysoPC(20:4) and LysoPC(20:3) while others were down-regulated: LysoPC(18:3) and LysoPC(18:1).Conclusions: Metabolomic analysis of follicular fluid revealed that with the increase in age, several differential metabolites are at play. Among these metabolites, lipid metabolism undergoes significant changes that affect the development of oocytes thus causing reduced fertility in older women. These differential metabolites related to follicular development may provide possible detection and treatment targets for promoting oocyte health, and provide scientific basis for understanding the environment of oocyte development.

scholarly journals Variation in chemical composition and antimalarial activities of two samples of Terminalia albida collected from separate sites in Guinea

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Aissata Camara ◽  
Mohamed Haddad ◽  
Mohamed Sahar Traore ◽  
Florence Chapeland-Leclerc ◽  
Gwenaël Ruprich-Robert ◽  
...  
Keyword(s):  
Chemical Composition ◽  
High Performance ◽  
High Resolution Mass Spectrometry ◽  
Murine Models ◽  
Public Health Perspective ◽  
Chemical Fingerprints ◽  
Two Samples ◽  
Geographical Locations

Abstract Background The disparity of harvesting locations can influence the chemical composition of a plant species, which could affect its quality and bioactivity. Terminalia albida is widely used in traditional Guinean medicine whose activity against malaria has been validated in vitro and in murine models. The present work investigated the antimalarial properties and chemical composition of two samples of T. albida collected from different locations in Guinea. Method T. albida samples were collected in different locations in Guinea, in Dubréka prefecture (West maritime Guinea) and in Kankan prefecture (eastern Guinea). The identity of the samples was confirmed by molecular analysis. In vitro antiplasmodial activity of the two extracts was determined against the chloroquine resistant strain PfK1. In vivo, extracts (100 mg/kg) were tested in two experimental murine models, respectively infected with P. chabaudi chabaudi and P. berghei ANKA. The chemical composition of the two samples was assessed by ultra-high-performance liquid chromatography coupled to high resolution mass spectrometry. Results In vitro, the Dubréka sample (TaD) was more active with an IC50 of 1.5 μg/mL versus 8.5 μg/mL for the extract from Kankan (TaK). In vivo, the antiparasitic effect of TaD was substantial with 56% of parasite inhibition at Day 10 post-infection in P. chabaudi infection and 61% at Day 8 in P. berghei model, compared to 14 and 19% inhibition respectively for the treatment with TaK. In addition, treatment with TaD further improved the survival of P. berghei infected-mice by 50% at Day 20, while the mortality rate of mice treated with Tak was similar to the untreated group. The LC/MS analysis of the two extracts identified 38 compounds, 15 of which were common to both samples while 9 and 14 other compounds were unique to TaD and TaK respectively. Conclusion This study highlights the variability in the chemical composition of the species T. albida when collected in different geographical locations. These chemical disparities were associated with variable antimalarial effects. From a public health perspective, these results underline the importance of defining chemical fingerprints related to botanical species identification and to biological activity, for the plants most commonly used in traditional medicine.

Phytochemical, Analytical and Medicinal Studies of Holoptelea integrifolia Roxb. Planch - A Review

2019 ◽  
Vol 5 (4) ◽  
pp. 270-277 ◽  
Author(s):  
Vijay Kumar ◽  
Simranjeet Singh ◽  
Ragini Bhadouria ◽  
Ravindra Singh ◽  
Om Prakash
Keyword(s):  
Liquid Chromatography ◽  
Thin Layer ◽  
Thin Layer Chromatography ◽  
High Performance ◽  
Biologically Active ◽  
Toxicological Studies ◽  
Wide Range ◽  
Layer Chromatography

Holoptelea integrifolia Roxb. Planch (HI) has been used to treat various ailments including obesity, osteoarthritis, arthritis, inflammation, anemia, diabetes etc. To review the major phytochemicals and medicinal properties of HI, exhaustive bibliographic research was designed by means of various scientific search engines and databases. Only 12 phytochemicals have been reported including biologically active compounds like betulin, betulinic acid, epifriedlin, octacosanol, Friedlin, Holoptelin-A and Holoptelin-B. Analytical methods including the Thin Layer Chromatography (TLC), High-Performance Thin Layer Chromatography (HPTLC), High-Performance Liquid Chromatography (HPLC) and Liquid Chromatography With Mass Spectral (LC-MS) analysis have been used to analyze the HI. From medicinal potency point of view, these phytochemicals have a wide range of pharmacological activities such as antioxidant, antibacterial, anti-inflammatory, and anti-tumor. In the current review, it has been noticed that the mechanism of action of HI with biomolecules has not been fully explored. Pharmacology and toxicological studies are very few. This seems a huge literature gap to be fulfilled through the detailed in-vivo and in-vitro studies.

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