Investigating the pharmacokinetics of a grape seed-derived proanthocyanidin extract in healthy human subjects.
| dc.contributor.advisor | Petersen-Ross, Kelly | en_ZA |
| dc.contributor.advisor | Kellermann, Tracy | en_ZA |
| dc.contributor.advisor | Smith, Carine | en_ZA |
| dc.contributor.author | Abdulla, Zohra Bibi | en_ZA |
| dc.contributor.other | Stellenbosch University. Faculty of Medicine and Health Sciences. Dept. of Medicine. Division of Clinical Pharmacology. | en_ZA |
| dc.date.accessioned | 2025-01-24T08:00:04Z | en_ZA |
| dc.date.available | 2025-01-24T08:00:04Z | en_ZA |
| dc.date.issued | 2024-12 | en_ZA |
| dc.description | Thesis (MSc)--Stellenbosch University, 2024. | en_ZA |
| dc.description.abstract | ENGLISH ABSTRACT: Introduction: Oxidative stress and inflammation have been implicated in the ageing phenotype associated with the development of non-communicable diseases (NCDs). Several pre-clinical and clinical studies have demonstrated the beneficial properties of grape seed-derived polyphenols in mediating oxidative stress. However, limited information on the bioavailability and pharmacokinetics of these products is available. This study consisted of the development and validation of a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method to quantify catechin, epicatechin and procyanidin B1 as constituents of a grape seed derived supplement, OxiprovinTM in human plasma. Subsequently, the method was applied to an early phase clinical trial investigating the pharmacokinetics of these analytes following the administration of a single dose of 140 mg. Methods: Positive electrospray ionisation (ESI) was used to detect catechin, epicatechin and procyanidin B1 on a Shimadzu-8040 mass spectrometer with (+)-catechin-2,3,4-13C3 as an internal standard. A double liquid-liquid extraction (LLE) method was used to extract the analytes from human plasma using 50 mM ammonium bicarbonate in water and ethyl acetate in the first extraction step and ethyl acetate: acetone (10:1, v/v) in the second. Chromatographic separation was achieved on an Agilent XDB-C8 column (4.6 x 100 mm, 5 µm) with a gradient method at a flow rate of 0.600 mL/min over a total run time of 10 minutes. The mobile phases consisted of water + 0.1% formic acid (A) and methanol + 0.1% formic acid (B). The analyte to internal standard peak area ratios were plotted against the nominal concentrations to generate a calibration curve with a quadratic regression weighted by 1/c2, over the range 19.5-2 500 ng/mL for catechin and epicatechin and 39.1-2 500 ng/mL for procyanidin B1. In an early phase clinical trial, sixteen healthy volunteers (four male and 12 female) were recruited. Eight participants received a placebo and the other eight were administered a dose of 140 mg of OxiprovinTM. Blood samples were collected at 0 hours (baseline) and at 1, 2, 3, 6 and 24 hours post administration of the supplement, and the resulting plasma was stored at -80°C until analysis. Results and Discussion: During inter-day validations, the average accuracy of calibration standards ranged from 93.5-106.3% (% CV 2.6-7.1%) for catechin, 96.7-103.1% (% CV 4.2-11.7%) for epicatechin and 90.0-103.5% (% CV 3.8-9.9%) for procyanidin B1. For quality controls, the average accuracy ranged from 97.7-106.8% (% CV = 6.9-14.7%), 93.1-101.6% (% CV = 4.9-14.7%) and 96.0-110.1% (% CV = 10.0-19.8%) for catechin, epicatechin and procyanidin B1, respectively. Endogenous matrix effects were shown to have negligible effects on the quantification of the analytes when plasma samples from six different sources were analysed. The average recovery of catechin, epicatechin and procyanidin B1 was 78.7%, 70.6% and 52.4%, respectively. Furthermore, catechin, epicatechin and procyanidin B1 were found to be stable in plasma when subjected to three freeze-thaw cycles, on bench at room temperature for up to six hours and at -80°C for 27 days. All three analytes were also found to be stable in whole blood for up to 2 hours on bench at room temperature. Lastly, 2% haemolysis did not affect the reproducibility of the method. The validated method was used to quantify catechin, epicatechin and procyanidin B1 in the human plasma samples obtained from the trial. During the trial, no adverse events were reported, and the supplement was well-tolerated. Upon analysis, no analytes were detected in the plasma samples obtained at each time point. Conclusion: A LC-MS/MS method was successfully developed and validated according to United Staes Food and Drug Administration (FDA) and European Medicines Agency (EMA) guidelines for the quantification of catechin, epicatechin and procyanidin B1 in human plasma. The analytes were undetectable in the plasma samples collected at each time point during the trial. Due to impacts of metabolism, secondary metabolites may be detected at higher concentrations and using a more sensitive instrument may allow for lower assay ranges. Furthermore, future studies on urine or faecal samples may provide insight to the route of these parent compounds. | en_ZA |
| dc.description.abstract | AFRIKAANSE OPSOMMING: Inleiding: Oksidatiewe stres en inflammasie is gekoppel aan die verouderingseienskappe wat geassosieer word met die ontwikkeling van nie-oordraagbare siektes (NOS’e). Verskeie voor-kliniese en kliniese studies het die voordelige eienskappe van druiwesaad-afgeleide polifenole in die bemiddeling van oksidatiewe stres gedemonstreer. Daar is egter beperkte data oor die biobeskikbaarheid en farmakokinetika van hierdie produkte. Hierdie studie het bestaan uit die ontwikkeling en bekragtiging van 'n vloeibare kromatografie-tandem massa spektrometrie (VKMS/MS) metode om die belangrikste bestanddele van 'n druiwesaad-afgeleide aanvulling, OxiprovinTM , naamlik katechien, epikatechien en prosianidien B1, in menslike plasma te kwantifiseer. Daarna is die metode toegepas op 'n vroeë-fase kliniese proef wat die farmakokinetika van hierdie analiete ondersoek het na die toediening van 'n enkele dosis van OxiprovinTM 140 mg. Metodes: Positiewe elektrosproei-ionisering (ESI) is gebruik om katechien, epikatechien en prosianidien B1 op 'n Shimadzu-8040 massa spektrometer te vind met (+)-katechien-2,3,4-13C3 as 'n interne standaard. 'n Dubbele vloeibare-vloeibare ekstraksie (LLE) metode is gebruik om die analiete uit menslike plasma te onttrek met 50 mM ammonium bikarbonaat in water en etielasetaat in die eerste ekstraksie-stap en etielasetaat:aseton (10:1, v/v) in die tweede stap. Kromatografiese skeiding is verkry op 'n Agilent XDB-C8 kolom (4.6 x 100 mm, 5 µm) met 'n gradiënt metode teen 'n vloeitempo van 0.600 mL/min oor 'n totale looptyd van 10 minute. Die mobiele fases het bestaan uit water + 0.1% metanoësuur (A) en metanol + 0.1% metanoësuur (B). Die analiet-tot-interne standaard piekareaverhoudings is teen die nominale konsentrasies getrek om 'n kalibrasiekurwe met 'n kwadratiese regressie gewig deur 1/c2 te genereer, oor die reeks 19.5-2 500 ng/mL vir katechien en epikatechien, en 39.1-2 500 ng/mL vir prosianidien B1. 'n Vroeë-fase kliniese proef het 16 gesonde vrywilligers (4 mans en 12 vroue) gewerf. Agt deelnemers het 'n foppil ontvang en die ander 8 is 'n dosis van OxiprovinTM 140 mg toegedien. Bloedmonsters is by 0-uur (basislyn) en by 1-, 2-, 3-, 6-, en 24-uur na toediening van die aanvulling versamel en die verkrygde plasma is teen -80°C gestoor totdat dit ontleed is. Resultate en Bespreking: Gedurende inter-dag bekragtigings het die gemiddelde akkuraatheid van die kalibrasie standaarde gewissel van 93.5-106.3% (% CV 2.6-7.1) vir katechien, 96.7-103.1% (% CV 4.2- 11.7) vir epikatechien en 90.0-103.5% (% CV 3.8-9.9) vir prosianidien B1. Vir kwaliteitsbeheer het die gemiddelde akkuraatheid gewissel van 97.7-106.8% (% CV = 6.9-14.7%), 93.1-101.6% (% CV = 4.9- 14.7%) en 96.0-110.1% (% CV = 10.0-19.8%) vir katechien, epikatechien en prosianidien B1, onderskeidelik. Endogene matriks-effekte het getoon dat dit onbeduidende effekte op die kwantifikasie van die analiete gehad het met die ontleding van plasma monsters van ses verskillende bronne. Die gemiddelde verhaling van katechien, epikatechien en prosianidien B1 was 78.7%, 70.6% en 52.4%, onderskeidelik. Verder is dit gevind dat katechien, epikatechien en prosianidien B1 stabiel was in plasma wanneer dit aan 3 vries-ontdooi siklusse op die werksbank teen kamertemperatuur vir tot 6 uur en teen -80°C vir 27 dae blootgestel is. Al 3 analiete was ook stabiel in heelbloed vir tot 2 uur op die werksbank teen kamertemperatuur. Laastens, 2% hemolise het nie die herhaalbaarheid van die metode beïnvloed nie. Die bekragtigde metode is gebruik om katechien, epikatechien en prosianidien B1 in menslike plasmamonsters wat uit die proef verkry is te kwantifiseer. Tydens die verhoor is geen nadelige gebeurtenisse aangemeld nie, en die aanvulling is goed verdra. Met ontleding is geen analiete opgespoor in die plasmamonsters wat op elke tydstip verkry is nie. Gevolgtrekking: 'n LK-MS/MS metode is suksesvol ontwikkel en bekragtig volgens die Verenigde State se Voedsel- en Geneesmiddeladministrasie (FDA) en Europese Geneesmiddelsagentskap (EMA) riglyne vir die kwantifikasie van katechien, epikatechien en prosianidien B1 in menslike plasma. Die metode is toegepas op 'n vroeë-fase kliniese proef van 16 deelnemers om die farmakokinetiese profiel van die aanvulling OxiprovinTM te evalueer. Geen analiete is egter in die plasmamonsters wat by elke tydstip versamel is, opgespoor nie. As gevolg van die impak van metabolisme, kan sekondêre metaboliete by hoër konsentrasies opgespoor word en die gebruik van 'n meer sensitiewe instrument kan laer toetsreekse toelaat. Verder kan toekomstige studies oor urine of fekale monsters insig gee oor die roete van hierdie ouerverbindings. | af_ZA |
| dc.description.version | Masters | en_ZA |
| dc.format.extent | xix, 108 pages : illustrations | en_ZA |
| dc.identifier.uri | https://scholar.sun.ac.za/handle/10019.1/131549 | en_ZA |
| dc.language.iso | en | en_ZA |
| dc.publisher | Stellenbosch : Stellenbosch University | en_ZA |
| dc.rights.holder | Stellenbosch University | en_ZA |
| dc.subject.lcsh | Pharmacokinetics | en_ZA |
| dc.subject.lcsh | Polyphenols | en_ZA |
| dc.subject.lcsh | Oxidative stress | en_ZA |
| dc.subject.lcsh | Bioavailability | en_ZA |
| dc.subject.lcsh | Liquid chromatography | en_ZA |
| dc.subject.lcsh | UCTD | en_ZA |
| dc.title | Investigating the pharmacokinetics of a grape seed-derived proanthocyanidin extract in healthy human subjects. | en_ZA |
| dc.type | Thesis | en_ZA |