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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Effect of cissampelos capensis rhizome extract on human sperm capacitation and acrosome reaction

Shalaweh, Salem January 2013 (has links)
>Magister Scientiae - MSc / Cissampelos capensis, is commonly known by the Afrikaans name ‟dawidjies” or ‟dawidjieswortel”. C. capensis is the most important and best known medicinal plant of the family Menispermaceae used by the Khoisan and other rural people in the western regions of South Africa. Among numerous other ailments, it is traditionally taken to treat male fertility problems. Yet, no studies have investigated the effects of this plant or its extracts on human spermatozoa. The aim of study was to investigate the effects of C. capensis rhizome extracts on sperm function.
22

Teofilina associada ou não à heparina como agente capacitante para produção in vitro de embriões bovinos / Theophylline with or without heparin as agent empowering for in vitro production of bovine embryos

Silva, Laíla Pereira da 27 February 2015 (has links)
Made available in DSpace on 2016-05-02T13:55:22Z (GMT). No. of bitstreams: 1 Laila Pereira da Silva Dissertacao.pdf: 2576409 bytes, checksum: d8ddb33c748f481b6487512d8f098802 (MD5) Previous issue date: 2015-02-27 / Fundacao de Amparo a Pesquisa do Estado de Minas Gerais / The in vitro production (IVP) of bovine embryos despite already used on a commercial scale, presents high variability in the results, that can often be attributed to the fertilization step. Therefore, it is important to research factors related to semen, such as sperm capacitation process. The aim of the study was to evaluate theophylline or its combination with heparin as possible replacement capacitation agent in the development of in vitro produced embryos and in acrosome reaction of sperm cells. The experiment was carried out with 4 bulls and 3 treatments, with 12 experimental groups. Each bull was evaluated in all treatments as described below: Treatment 1 (T1): Heparin - 10mg / ml; Treatment 2 (T2): Theophylline - 5 mM; Treatment 3 (T3): Heparin (10 mg / ml) + theophylline (5mM). The bulls semen was thawed and exposed to incubation in three treatments for 0, 6, 12 and 18h, subsequently stained with Trypan blue / Giemsa and analyzed by electron microscopy for assessment of the acrosome reaction. For IVP of embryos capacitation agents added to fertilization medium were evaluated utilizing the same bulls. In sperm analysis, real acrosome reaction rate was higher (p<0,05) at 0h time while the higher dead spermatozoa rate (p<0,05) was observed at 12 h (84,46 ± 5,82 ) and 18h (86,75 ± 4,19). The IVP embryos rate (37,97 ± 13) and the hatching rate (33,50 ± 14) were higher (p<0,05) in heparin treatment. There was no influence of bull or treatments (p> 0.05) in the acrosome reaction analysis. The use of theophylline as a capacitation agent decreased embryo production rates in IVF, however was as efficient as heparin in acrosome reaction induction. / A produção in vitro de embriões (PIVE) bovinos, apesar de já utilizada em escala comercial, apresenta elevada variabilidade em seus resultados, que pode frequentemente ser atribuída à etapa de fertilização. Sendo assim, torna-se importante o estudo dos fatores relacionados ao sêmen, como o processo de capacitação espermática. O objetivo do estudo foi avaliar a teofilina como agente de capacitação substituto ou associado à heparina no desenvolvimento de embriões produzidos in vitro e sobre a reação acrossômica das células espermáticas. O experimento foi realizado com 4 touros e 3 tratamentos, totalizando 12 grupos experimentais. Cada touro foi avaliado em cada tratamento descrito a seguir: Tratamento 1 (T1): Heparina - 10µg/mL; Tratamento 2 (T2): Teofilina 5 mM; Tratamento 3 (T3): Heparina (10µg/mL) + Teofilina (5mM). O sêmen dos touros foi descongelado e submetido à incubação com os três tratamentos por 0, 6, 12 e 18h, posteriormente corados com Trypan blue/ Giemsa e analisados em microscopia eletrônica para avaliação da reação acrossômica. Para a PIVE os agentes de capacitação adicionados aos meios de fertilização foram testados utilizando os mesmos touros. Na análise espermática a taxa de reação acrossômica verdadeira foi maior (p<0,05) no tempo 0h enquanto para os espermatozoides mortos foi observada maior taxa (p<0,05) nos tempos de 12h (84,46 ± 5,82) e 18h (86,75 ± 4,19). A taxa de embriões produzidos na PIVE (37,97 ± 13) e a taxa de eclosão (33,50 ± 14) foram maiores (p<0,05) para o tratamento heparina. Não houve influência de touro ou de tratamentos (p>0,05) na análise de reação acrossômica. A utilização da teofilina como agente de capacitação reduziu as taxas de produção embrionária na fertilização in vitro, no entanto foi tão eficiente quanto à heparina na indução da reação do acrossoma.
23

Organisation und Dynamik der Phospholipide in der Zell- und Akrosommembran von Eberspermien während der Kapazitation und Akrosomreaktion

Kurz, Anke 06 July 2005 (has links)
Eine wichtige Eigenschaft der Plasmamembran eukaryotischer Zellen ist die stabile transversale Asymmetrie der Phospholipide. Sie wird energieabhängig durch die Aktivität einer Aminophospholipidtranslokase aufrechterhalten und gilt als wichtige Voraussetzung für die Homöostasis der Zellen. Die Plasmamembran einiger Säugerzellen weist zudem laterale Lipiddomänen auf, denen eine wesentliche Bedeutung bei der Signaltransduktion zugeschrieben wird. Während der Genese durchlaufen die Membranen der Säugerspermien intensive Veränderungen. Um die Bedeutung der Phospholipidasymmetrie für die Funktion der Spermien zu untersuchen, wurde die Lokalisation und Dynamik von Phosphatidylserin in der Zell- und Akrosommembran von Eberspermien im Verlauf von Kapazitation und Akrosomreaktion betrachtet. Unter Ausnutzung der selektiven, kalziumabhängigen Bindung von AnnexinV an endogenes Phosphatidylserin konnte dessen Lokalisation an morphologisch differenzierten Zellen verfolgt werden. Eine Markierung der Zellen mit NBD-markierten Phospholipidanaloga lieferte zudem Informationen zur Dynamik der Phospholipide in der Plasmamembran. Die Differenzierung der Zellen erfolgte entweder am Durchflusszytometer oder fluoreszenz- bzw. elektronenmikroskopisch. Die Ergebnisse der vorliegenden Arbeit weisen sowohl auf eine transversale als auch laterale Ungleichverteilung der Lipide in der Zell- und Akrosommembran während der Genese der Spermien hin. Neben der stabilen transversalen Phospholipidasymmetrie der Plasmamembran konnte erstmals eine zytoplasmatische Lokalisation von Phosphatidylserin auf der äußeren Akrosommembran nachgewiesen werden. Somit akkumulieren die beiden einander zugewandten zytoplasmatischen Monolayer von Plasmamembran und äußerer Akrosommembran Phosphatidylserin. Kapazitationsbedingt kommt es zu einer engen Wechselwirkung zwischen Plasmamembran und äußerer Akrosommembran. Die Ausbildung lateraler Membrandomänen, in denen Phosphatidylserin zytoplasmatisch akkumuliert, wird als Voraussetzung für diese enge Assoziation diskutiert. Weitere Hinweise auf eine funktionelle Bedeutung lateraler Membrandomänen lieferten die Arbeiten zur Isolation Triton-unlöslicher Lipiddomänen aus der Plasmamembran von Forellenspermien. / One of the essential qualities of cell membranes in Eucaryotae is a stable transverse phospholipid asymmetry. It is regulated and maintained by ATP-dependent action of an aminophospholipid translocase and is a major prerequisite for cell homeostasis. The plasma membranes of several mammalian cells show moreover lateral lipid domains, which are imputed to play a significant role in signal transduction. The membranes of mammalian spermatozoa undergo significant changes during genesis. The localisation and dynamics of phosphatidylserine in the cell as well as acrosome membranes of boar sperm cells was studied during capacitation and acrosome reaction to assess the relevance of lipid asymmetry for sperm function. The localisation of endogenous phosphatidylserine in morphologically differentiated cells was followed using the selective calcium depending binding of annexinV. Information on the transverse dynamics of phospholipids in the plasma membrane was obtained by labelling the cells with a NBD-phospholipid analogues. The morphological status of the cells was assessed by flow cytometry, fluorescence and electron microscopy. The results of this study indicate both a transversal and lateral inhomogenous distribution of lipids in the cell membrane as well as in the outer acrosome membrane during sperm genesis. The plasma membrane of boar sperm shows a stable transversal lipid asymmetry characterised by an accumulation of phosphatidylserine in the cytoplasmic monolayer. Moreover a cytoplasmic localisation of phosphatidylserine on the outer acrosome membrane could be detected for the first time. Therefore the two facing cytoplasmic leaflets of the outer acrosome and cell membrane contain phosphatidylserine. Applying microscopy substantiated the hypothesis that there are close interactions between the cell membrane and the outer layer of the acrosome membrane because of capacitation. The cytoplasmic accumulation of phosphatidylserine in lateral lipid domains is probably essential for the strong association of plasma and outer acrosome membrane finally leading to local fusions of both membranes. An indication for the functional meaning of lateral membrane domains in sperm cells was futher deduced from the isolation of Triton-insoluble lipid domains from membranes of trout sperm cells.
24

Análisis mediante citometría de flujo de la respuesta de los espermatozoides de verraco a diferentes medios de incubación

Matas Parra, Carmen 04 October 1996 (has links)
El objetivo de este trabajo ha sido evaluar la capacitación y reacción acrosómica de espermatozoides de verraco eyaculados lavados a través de un gradiente de percoll y no lavados e incubados en medio de fecundación M199 suplementado con progesterona o con complejos cumulus-ovocito así como la penetración espermática de estos con ovocitos homólogos madurados in vitro. La determinación de la capacitación se realizó mediante el uso de lectinas (PNA, SJA y ECA) y citometría de flujo. Los resultados mostraron que la progesterona posee efecto protector sobre la vitalidad espermática y los mayores porcentajes de reacción acrosómica ocurren ente los 45-90 minutos de incubación, En cuanto a la penetración espermática no hubo diferencias entre espermatozoides lavados y no lavados. / The purpose of the present study was to evaluate the sperm capacitation and acrosome reaction of spermatozoa washed in Percoll and unwashed undergo in an in vitro incubation system with progesterone or cumulus-oocyte and the penetration rate in homologous oocytes matured in vitro. The evaluation was done with lectin (PNA, SJA and ECA) and flow cytometry. The results shown that progesterone had a protective effect on sperm vitality and the highest percentages of acrosome reaction were obtained between 45-90 minutes of incubation. The penetration rate was similar between washed and unwashed spermatozoa.
25

Integridade e funcionalidade dos espermatozóides ovinos submetidos à criopreservação após a incorporação de colesterol, desmosterol, ácido oléico-linoléico e alfa-lactoalbumina /

Azevedo, Hymerson Costa. January 2006 (has links)
Orientador: Sony Dimas Bicudo / Banca: Rui Machado / Banca: Jairo Pereira Neves / Banca: César Roberto Esper / Banca: Cezinande de Meira / Resumo: Objetivando testar a ação do colesterol, desmosterol, ácido oléico-linoléico ou Q-Iactoalbumina sobre os espermatozóides ovinos, alíquotas de sêmen de 25 carneiros foram submetidas à criopreservação após tratamento com essas substâncias. O sêmen foi avaliado antes do processamento e após a refrigeração, descongelação e incubação quanto à, cinética pela análise subjetiva e computadorizada (CASA), morfologia, avaliação simultânea da integridade da membrana plasmática (IMP) e do acrossomo (IAC) e do potencial de membrana mitocondrial (PMM) pela associação da aglutinina de Pisum sativum conjugada ao isotiocianato de fluoresceína (FITC-PSA), iodeto de propídio (PI) e JC-1 e, status de capacitação pela c10rtetraciclina (CTC). A influência dos aditivos em poucos parâmetros não foi suficiente para sugerir a superioridade de qualquer um dos tratamentos. A criopreservação provocou prejuízos à cinética, IMP, IAC, PMM, além de induzir a capacitação e reação do acrossomo. Foram observadas diferenças entre grupos de carneiros quanto ao status de capacitação no sêmen in natura, assim como na sensibilidade desse sêmen à crioinjúria e criocapacitação. Após a descongelação, as mudanças semelhantes à capacitação foram maiores nos animais de menor IMP. A segregação dos carneiros de acordo com a crioresistência da membrana plasmática norteou o comportamento de vários outros parâmetros. Conclui-se, que o colesterol, desmosterol, ácido oléico-linoléico e alactoalbumina não protegem o sêmen ovino contra as crioinjúrias, que a congelação-descongelação é mais danosa que a refrigeração e, que existem diferenças entre grupos de indivíduos relacionadas à crioresistência e criocapacitação espermática. / Abstract: In order to evaluate the proteeting aetion of some substanceson ram spermatozoa, semen samples of 25 rams were colleeted and submitted to cryopreservation after treatment with cholesterol, desmosterol, oleic-linoleic acid or Q-Iactalbumin. Before the processing and after the procedures of cooling, freezing-thawing and incubation, semen was evaluated as to kínetcs by subjective and computerized analyses (CASA), morphology, simultaneously to plasma membrane integrity (PMI), acrosome integrity (ACI) and mitochondrial membrane potential (MMP) by isothiocyanate-conjugated Pisum sativum (FITCPSA), propidium iodide (PI) and JC-1 combination and as to sperm capacitation and acrosome reaction determined by chlortetracycline (CTC) assay. The influence resulted from the additives in a few parameters was not enough to suggest the superiority of any treatments. The cryopreservation process, especially the freezing-thawing, promotes damages to kinetics, PMI, ACI, MMP and induees accelerated eapacitation and acrosome reaction in spermatozoa. Differenees among groups of rams were observed regarding capacitation status in fresh semen as well as the sensibility of their semen to cryoinjury and cryocapacitation. Higher and more accelerated capacitation-like ehanges were observed in groups of rams presenting lower plasmatic membrane cryoresistance after thawing. The segregation of rams in different levels of PMI influenced the behavior of several other parameters. It was concluded that cholesterol, desmosterol, oleic-Iinoleic acid and Q-Iactalbumin do not protect the ram semen against the cryoinjuries as well as freezing-thawing is more harmful than cooling. Important differenees among groups of individuais were noticed as for the spermatozoa resistance to the damages provoked by cryopreservation such as the eryocapacitation susceptibility. / Doutor
26

Investigations on the in vitro effects of aqueous Eurycoma longifolia Jack extract on male reproductive functions

Erasmus, Nicolete January 2012 (has links)
<p>Eurycoma longifolia (Tongkat Ali / TA) is a Malaysian shrub used to treat various illnesses including male infertility. Considering that TA is also used to improve male fertility and no report&nbsp / regarding its safety has been published, this study investigated the effects of a patented, aqueous TA extract on various sperm and testicular functions. Materials and Methods This study&nbsp / encompasses two parts (part 1: on spermatozoa / part 2: on TM3-Leydig and TM4-Sertoli cells). Part 1: Semen samples of 27 patients and 13 fertile donors were divided into two groups,&nbsp / washed and swim-up prepared spermatozoa, and incubated with different concentrations of TA (1, 10, 20, 100, 2000 &mu / g/ml) for 1 hour at 37&deg / C. A sample without addition of TA served as control. After incubation with TA,&nbsp / the following parameters were evaluated: viability (Eosin-Nigrosin test), total and progressive motility (CASA), acrosome reaction (triple stain technique), sperm production of reactive oxygen&nbsp / species (ROS / dihydroethidium test / DHE), sperm DNA fragmentation (TUNEL assay) and mitochondrial membrane potential (&Delta / &psi / m) (Depsipher kit). Part 2: TM3-Leydig and TM4-Sertoli cells&nbsp / incubated with different concentrations of TA (0.4, 0.8, 1.6, 3.125, 6.25, 12.5, 25, 50 &mu / g/ml) and control (without extract) for 48 and 96 hours. After incubation with TA, the following parameters were&nbsp / evaluated: viability (XTT), cell proliferation (protein assay), testosterone (testosterone ELISA test) and pyruvate (pyruvate assay). Results Part 1: For washed spermatozoa, significant&nbsp / dose-dependent trends were found&nbsp / for viability, total motility, acrosome reaction and sperm ROS production. However, these trends were only significant if the highest concentrations were included in the calculation. In the swim-up spermatozoa, ROS production of spermatozoa showed a biphasic relationship with its lowest percentage at 10 &mu / g/ml, yet, no significance could be&nbsp / observed (P=0.9505). No influence of TA could be observed for sperm DNA fragmentation nor &Delta / &psi / m.</p>
27

Investigations on the in vitro effects of aqueous Eurycoma longifolia Jack extract on male reproductive functions

Erasmus, Nicolete January 2012 (has links)
<p>Eurycoma longifolia (Tongkat Ali / TA) is a Malaysian shrub used to treat various illnesses including male infertility. Considering that TA is also used to improve male fertility and no report&nbsp / regarding its safety has been published, this study investigated the effects of a patented, aqueous TA extract on various sperm and testicular functions. Materials and Methods This study&nbsp / encompasses two parts (part 1: on spermatozoa / part 2: on TM3-Leydig and TM4-Sertoli cells). Part 1: Semen samples of 27 patients and 13 fertile donors were divided into two groups,&nbsp / washed and swim-up prepared spermatozoa, and incubated with different concentrations of TA (1, 10, 20, 100, 2000 &mu / g/ml) for 1 hour at 37&deg / C. A sample without addition of TA served as control. After incubation with TA,&nbsp / the following parameters were evaluated: viability (Eosin-Nigrosin test), total and progressive motility (CASA), acrosome reaction (triple stain technique), sperm production of reactive oxygen&nbsp / species (ROS / dihydroethidium test / DHE), sperm DNA fragmentation (TUNEL assay) and mitochondrial membrane potential (&Delta / &psi / m) (Depsipher kit). Part 2: TM3-Leydig and TM4-Sertoli cells&nbsp / incubated with different concentrations of TA (0.4, 0.8, 1.6, 3.125, 6.25, 12.5, 25, 50 &mu / g/ml) and control (without extract) for 48 and 96 hours. After incubation with TA, the following parameters were&nbsp / evaluated: viability (XTT), cell proliferation (protein assay), testosterone (testosterone ELISA test) and pyruvate (pyruvate assay). Results Part 1: For washed spermatozoa, significant&nbsp / dose-dependent trends were found&nbsp / for viability, total motility, acrosome reaction and sperm ROS production. However, these trends were only significant if the highest concentrations were included in the calculation. In the swim-up spermatozoa, ROS production of spermatozoa showed a biphasic relationship with its lowest percentage at 10 &mu / g/ml, yet, no significance could be&nbsp / observed (P=0.9505). No influence of TA could be observed for sperm DNA fragmentation nor &Delta / &psi / m.</p>
28

Integridade e funcionalidade dos espermatozóides ovinos submetidos à criopreservação após a incorporação de colesterol, desmosterol, ácido oléico-linoléico e alfa-lactoalbumina

Azevedo, Hymerson Costa [UNESP] 24 November 2006 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:35:12Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-11-24Bitstream added on 2014-06-13T20:06:44Z : No. of bitstreams: 1 azevedo_hc_dr_botfmvz.pdf: 1090855 bytes, checksum: bd7f7a04aa00c86d1200aecb917ca794 (MD5) / Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Objetivando testar a ação do colesterol, desmosterol, ácido oléico-linoléico ou Q-Iactoalbumina sobre os espermatozóides ovinos, alíquotas de sêmen de 25 carneiros foram submetidas à criopreservação após tratamento com essas substâncias. O sêmen foi avaliado antes do processamento e após a refrigeração, descongelação e incubação quanto à, cinética pela análise subjetiva e computadorizada (CASA), morfologia, avaliação simultânea da integridade da membrana plasmática (IMP) e do acrossomo (IAC) e do potencial de membrana mitocondrial (PMM) pela associação da aglutinina de Pisum sativum conjugada ao isotiocianato de fluoresceína (FITC-PSA), iodeto de propídio (PI) e JC-1 e, status de capacitação pela c10rtetraciclina (CTC). A influência dos aditivos em poucos parâmetros não foi suficiente para sugerir a superioridade de qualquer um dos tratamentos. A criopreservação provocou prejuízos à cinética, IMP, IAC, PMM, além de induzir a capacitação e reação do acrossomo. Foram observadas diferenças entre grupos de carneiros quanto ao status de capacitação no sêmen in natura, assim como na sensibilidade desse sêmen à crioinjúria e criocapacitação. Após a descongelação, as mudanças semelhantes à capacitação foram maiores nos animais de menor IMP. A segregação dos carneiros de acordo com a crioresistência da membrana plasmática norteou o comportamento de vários outros parâmetros. Conclui-se, que o colesterol, desmosterol, ácido oléico-linoléico e alactoalbumina não protegem o sêmen ovino contra as crioinjúrias, que a congelação-descongelação é mais danosa que a refrigeração e, que existem diferenças entre grupos de indivíduos relacionadas à crioresistência e criocapacitação espermática. / In order to evaluate the proteeting aetion of some substanceson ram spermatozoa, semen samples of 25 rams were colleeted and submitted to cryopreservation after treatment with cholesterol, desmosterol, oleic-linoleic acid or Q-Iactalbumin. Before the processing and after the procedures of cooling, freezing-thawing and incubation, semen was evaluated as to kínetcs by subjective and computerized analyses (CASA), morphology, simultaneously to plasma membrane integrity (PMI), acrosome integrity (ACI) and mitochondrial membrane potential (MMP) by isothiocyanate-conjugated Pisum sativum (FITCPSA), propidium iodide (PI) and JC-1 combination and as to sperm capacitation and acrosome reaction determined by chlortetracycline (CTC) assay. The influence resulted from the additives in a few parameters was not enough to suggest the superiority of any treatments. The cryopreservation process, especially the freezing-thawing, promotes damages to kinetics, PMI, ACI, MMP and induees accelerated eapacitation and acrosome reaction in spermatozoa. Differenees among groups of rams were observed regarding capacitation status in fresh semen as well as the sensibility of their semen to cryoinjury and cryocapacitation. Higher and more accelerated capacitation-like ehanges were observed in groups of rams presenting lower plasmatic membrane cryoresistance after thawing. The segregation of rams in different levels of PMI influenced the behavior of several other parameters. It was concluded that cholesterol, desmosterol, oleic-Iinoleic acid and Q-Iactalbumin do not protect the ram semen against the cryoinjuries as well as freezing-thawing is more harmful than cooling. Important differenees among groups of individuais were noticed as for the spermatozoa resistance to the damages provoked by cryopreservation such as the eryocapacitation susceptibility.
29

Investigations on the in vitro effects of aqueous Eurycoma longifolia Jack extract on male reproductive functions

Erasmus, Nicolete January 2012 (has links)
Magister Scientiae (Medical Bioscience) - MSc(MBS) / Introduction: Eurycoma longifolia (Tongkat Ali; TA) is a Malaysian shrub used to treat various illnesses including male infertility. Considering that TA is also used to improve male fertility and no report regarding its safety has been published, this study investigated the effects of a patented, aqueous TA extract on various sperm and testicular functions. Materials and Methods: This study encompasses two parts (part 1: on spermatozoa; part 2: on TM3-Leydig and TM4-Sertoli cells). Part 1: Semen samples of 27 patients and 13 fertile donors were divided into two groups, washed and swim-up prepared spermatozoa, and incubated with different concentrations of TA (1, 10, 20, 100, 2000 μg/ml) for 1 hour at 37°C. A sample without addition of TA served as control. After incubation with TA, the following parameters were evaluated: viability (Eosin-Nigrosin test), total and progressive motility (CASA), acrosome reaction (triple stain technique), sperm production of reactive oxygen species (ROS; dihydroethidium test; DHE), sperm DNA fragmentation (TUNEL assay) and mitochondrial membrane potential (Δψm) (Depsipher kit). Part 2: TM3-Leydig and TM4-Sertoli cells incubated with different concentrations of TA (0.4, 0.8, 1.6, 3.125, 6.25, 12.5, 25, 50 μg/ml) and control (without extract) for 48 and 96 hours. After incubation with TA, the following parameters were evaluated: viability (XTT), cell proliferation (protein assay), testosterone (testosterone ELISA test) and pyruvate (pyruvate assay). Results Part 1: For washed spermatozoa, significant dose-dependent trends were found for viability, total motility, acrosome reaction and sperm ROS production. However, these trends were only significant if the highest concentrations were included in the calculation. In the swim-up spermatozoa, ROS production of spermatozoa showed a biphasic relationship with its lowest percentage at 10 μg/ml, yet, no significance could be observed (P=0.9505). No influence of TA could be observed for sperm DNA fragmentation nor Δψm. Part 2: The viability rates and protein production of TM3-Leydig and TM4-Sertoli cells at 48-hour exposure to TA showed increases whereas at 96-hour incubation periods viability and protein production declined especially as from concentration 25 μg/ml TA. Similar results could be seen for TM4-Sertoli cells pyruvate production. The testosterone production at 48-hour exposure marginally increased (P=0.0580) at the highest (50 μg/ml) concentration of TA. However, at 96-hour exposure to TA the testosterone production significantly (P=0.0065) increased. It is also apparent that after 96 hours the concentration of testosterone has increased [12 x 10-4 ng/ml] when compared to 48-hour exposure [6 x 10-7ng/ml] of Tongkat Ali. Conclusion: Part 1: Results indicate that the Tongkat Ali extract has no deleterious effects on sperm functions at therapeutically used concentrations (<2.5 μg/ml). Part 2: The cytotoxic effect of TA are only presented at higher concentration from 25 μg/ml. TM3-Leydig cells appears to be more resilient than TM4-Sertoli cells in viability and protein production yet at prolonged periods of exposure it is detrimental. Testosterone production only increases after 96 hours exposure to TA.
30

Untersuchungen zur kapazitationsassoziierten Signaltransduktion in humanen Spermatozoen und Evaluation des MACS-Verfahrens zur Ejakulataufbereitung

Kriegel, Christian 17 May 2013 (has links) (PDF)
Als Kapazitation bezeichnet man den im weiblichen Reproduktionstrakt stattfindenden Reifungsschritt, der Spermien das volle Fertilisierungspotential verleiht. Die molekularbiologischen Grundlagen dieses für eine erfolgreiche natürliche oder auch artifizielle Befruchtung essenziellen Prozesses sind bis heute nur unvollständig verstanden. Im Rahmen der vorliegenden Dissertation wurden die mit der Kapazitation einhergehenden funktionellen und strukturellen spermalen Veränderungen untersucht. Die kapazitative Stimulation führte zu einer gesteigerten Motilität bis hin zur Hyperaktivierung, zu einer vermehrt induzierten Akrosomenreaktion und zu einer deutlich reduzierten Apoptoseaktivität. Anhand von Inhibitionsexperimenten wurde die Rolle der potentiellen Signaltransduktoren Caspase-1, Calpain und Calmodulin analysiert. Dabei wies die Calmodulinantagonisierung auf eine ausgeprägte Calciumabhängigkeit aller untersuchten kapazitationsassoziierten Prozesse hin. Die Hemmung von Caspase-1 und Calpain führte zu einer Beeinträchtigung der Motilität und der Akrosomenreaktion ohne das Ausmaß der Apoptoseinduktion zu beeinflussen. Die vorstehend genannten Erkenntnisse wurden zur Evaluation verschiedener Ejakulataufbereitungsprotokolle genutzt. Dabei konnte gezeigt werden, dass die Kombination des modernen Verfahrens der immunomagnetische Zellseparation mit der etablierten Methode der Dichtegradientenzentrifugation dem einfachen Standard in Bezug auf die Anreicherung hochmotiler Spermien mit minimaler Apoptoseaktivität aus frischen wie auch aus kryokonservierten Ejakulaten deutlich überlegen war. Bedeutsam im Hinblick auf eine mögliche pratische Anwendung der immunomagnetischen Zellseparation erscheint der Befund, dass die durch das kombinierte Anreicherungsverfahren erhaltene Spermatozoensubpopulation im Hamsteroozytenpenetrationstest ein signifikant höheres Fertilisierungspotential zeigte.

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