Full Text Available
Note: Clicking the button above will open the full text document at the original institutional repository in a new window.
Thesis (PhD)--Stellenbosch University, 2018.
| Main Author: | |
|---|---|
| Other Authors: | |
| Format: | Thesis |
| Language: | en_ZA |
| Published: |
Stellenbosch : Stellenbosch University
2018
|
| Subjects: | |
| Tags: |
No Tags, Be the first to tag this record!
|
| _version_ | 1867613989144363008 |
|---|---|
| access_status_str | Open Access |
| author | Du Toit, Therina |
| author2 | Swart, Amanda C. |
| author_browse | Du Toit, Therina Swart, Amanda C. |
| author_facet | Swart, Amanda C. Du Toit, Therina |
| author_sort | Du Toit, Therina |
| collection | Thesis |
| dc_rights_str_mv | Stellenbosch University |
| description | Thesis (PhD)--Stellenbosch University, 2018. |
| format | Thesis |
| id | oai:scholar.sun.ac.za:10019.1/103260 |
| institution | Stellenbosch University (South Africa) |
| language | en_ZA |
| last_indexed | 2026-06-10T12:44:53.996Z |
| license_str | Other — see source repository |
| provenance_str_mv | Harvested via OAI-PMH from SUNScholar — Stellenbosch University Repository |
| publishDate | 2018 |
| publishDateRange | 2018 |
| publishDateSort | 2018 |
| publisher | Stellenbosch : Stellenbosch University |
| publisherStr | Stellenbosch : Stellenbosch University |
| record_format | dspace |
| source_str | SUNScholar — Stellenbosch University Repository |
| spelling | oai:scholar.sun.ac.za:10019.1/103260 The metabolism of 11β-hydroxyandrostenedione by steroidogenic enzymes yields metabolites contributing to the androgen pool in prostate cancer Du Toit, Therina Swart, Amanda C. Stellenbosch University. Faculty of Science. Dept. of Biochemistry. Adrenal androgens Prostate cancer Mass spectrometry Adrenal-linked endocrine diseases UCTD Thesis (PhD)--Stellenbosch University, 2018. ENGLISH ABSTRACT: This study describes: • The development and validation of three ultra-performance convergence chromatography tandem mass spectrometry (UPC2-MS/MS) analytical methods which were applied in the detection and quantification of C19 and C21 steroids, including C11-oxy C19 and C11-oxy C21 steroids; • The investigation into the contribution of adrenal 11β-hydroxyandrostenedione (11OHA4) and 11β-hydroxytestosterone (11OHT) to the pool of active androgens in the prostate, by following androgen metabolism in normal epithelial prostate PNT2, benign prostatic hyperplasia (BPH-1) and prostate cancer LNCaP, C4-2B and VCaP cell models; Steroid profiles revealed 11β-hydroxysteroid dehydrogenase type 2 (11βHSD2) activity in all the cell models, confirmed in the conversion of 11OHA4 to 11keto-androstenedione (11KA4), with reductive 17β-hydroxysteroid dehydrogenase (17βHSD) enzymes metabolising 11KA4, ultimately yielding 11keto-testosterone (11KT). • The in vitro investigation into the inactivation, reactivation, glucuronidation and sulfation of 11OHA4, 11OHT and their downstream metabolites; In prostate cancer (PCa) cell models, the conjugation of 11KT and 11ketodihydrotestosterone (11KDHT) were hampered compared to testosterone (T) and dihydrotestosterone (DHT), while the inactivation and reactivation of the C11-oxy C19 steroids were less efficient than the C19 steroids in BPH-1 cells. • The in vivo steroid profiles in PCa, BPH and castration-resistant prostate cancer (CRPC) tissue and plasma of healthy and PCa patients; Analyses of the C19 and C11-oxy C19 steroids, together with glucuronide and sulfate conjugates, showed increased unconjugated levels of 11KT and 11KDHT in plasma of PCa patients compared to a healthy subject, and 11OHA4, 11KT and 11KDHT levels were prominent in PCa tissue, while downstream inactive C11-oxy 3α-reduced metabolites were identified in BPH and CRPC tissue. AFRIKAANSE OPSOMMING: Hierdie studie beskryf die volgende: • Die ontwikkeling en validering van drie UPC2-MS/MS analitiese metodes wat vervolgens toegepas is in die skeiding en kwantifisering van steroïedmetaboliete. • Die ondersoek na 11OHA4 and 11OHT se bydrae tot die aktiewe androgeen poel in die prostaat; Androgeen metabolisme is in normale epiteel prostaat PNT2, BPH-1 en prostaat kanker LNCaP, C4-2B en VCaP selmodelle ondersoek. Die steroïdprofiele bevestig die teenwoordigheid van 11βHSD2 aktiwiteit in al die modelle in die omsetting van 11OHA4 na 11KA4, sowel as die aktiwiteit van 17βHSD wat vervolgens die omsetting van 11KA4 na 11KT gekataliseer het. • Die in vitro inaktivering, heraktivering en konjugering van 11OHA4 en 11OHT metaboliete; In prostaatkanker selmodelle was 11KT en 11KDHT konjugering oneffektief in vergelyking met T en DHT, en die inaktivering van die C11-oksie C19 steroïede was nie optimaal in vergelyking met die C19 steroïede in BPH-1 selmodelle nie. • Die in vivo steroïedprofiele in prostaatkankerweefsel, BPH weefsel en kastrasieweerstandige prostaatkankerweefsel en in plasma van gesonde normale individuë en prostaatkanker pasïente, asook die teenwoordigheid van ongekonjugeerde en gekonjugeerde steroïedmetaboliete in sirkulasie; Analiese toon dat ongekonjugeerde 11KT en 11KDHT hoër was in die plasma van pasïente met prostaatkanker; 11OHA4, 11KT en 11KDHT vlakke was abnormaal hoog in die prostaatkankerweefsel, terwyl onaktiewe C11-oksie 3α-gereduseerde metaboliete geïdentifiseer was in BPH weefsel en in kastrasie-weerstandige prostaatkankerweefsel. Doctoral 2018-01-28T16:04:37Z 2018-04-09T06:51:06Z 2018-08-31T03:00:05Z 2018-03 Thesis http://hdl.handle.net/10019.1/103260 en_ZA Stellenbosch University 223 pages : illustrations application/pdf Stellenbosch : Stellenbosch University |
| spellingShingle | Adrenal androgens Prostate cancer Mass spectrometry Adrenal-linked endocrine diseases UCTD Du Toit, Therina The metabolism of 11β-hydroxyandrostenedione by steroidogenic enzymes yields metabolites contributing to the androgen pool in prostate cancer |
| title | The metabolism of 11β-hydroxyandrostenedione by steroidogenic enzymes yields metabolites contributing to the androgen pool in prostate cancer |
| title_full | The metabolism of 11β-hydroxyandrostenedione by steroidogenic enzymes yields metabolites contributing to the androgen pool in prostate cancer |
| title_fullStr | The metabolism of 11β-hydroxyandrostenedione by steroidogenic enzymes yields metabolites contributing to the androgen pool in prostate cancer |
| title_full_unstemmed | The metabolism of 11β-hydroxyandrostenedione by steroidogenic enzymes yields metabolites contributing to the androgen pool in prostate cancer |
| title_short | The metabolism of 11β-hydroxyandrostenedione by steroidogenic enzymes yields metabolites contributing to the androgen pool in prostate cancer |
| title_sort | metabolism of 11β hydroxyandrostenedione by steroidogenic enzymes yields metabolites contributing to the androgen pool in prostate cancer |
| topic | Adrenal androgens Prostate cancer Mass spectrometry Adrenal-linked endocrine diseases UCTD |
| url | http://hdl.handle.net/10019.1/103260 |
| work_keys_str_mv | AT dutoittherina themetabolismof11bhydroxyandrostenedionebysteroidogenicenzymesyieldsmetabolitescontributingtotheandrogenpoolinprostatecancer AT dutoittherina metabolismof11bhydroxyandrostenedionebysteroidogenicenzymesyieldsmetabolitescontributingtotheandrogenpoolinprostatecancer |