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Genetic predisposition to DTT-induced DNA decondensationFouche, Anna Aletta. January 2006 (has links)
Thesis (MSc.(Anatomy)--Faculty of Health Sciences)-University of Pretoria, 2006. / Includes bibliographical references.
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Molecular analysis of human androgen receptor mutations causing motor neuronopathy or infertility.Abdullah, Abdullah A. Rasool January 1997 (has links)
No description available.
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Infertilitet - Vems rätt att bestämma? : En kvalitativ intervjustudie kring barnmorskors erfarenheter av att arbeta med infertilitet.Kristensen Berlin, Rebecka January 2016 (has links)
Abstrakt (svenska) Titel: Infertilitet – vems rätt att bestämma? En kvalitativ intervjustudie kring barnmorskors erfarenheter av att arbeta med infertilitet. Författare: Rebecka Kristensen Berlin, Umeå Universitet -Institutionen för Omvårdnad Syfte: Att undersöka hur barnmorskans erfarenheter av parens reaktioner uppfattas i samband med infertilitetsproblematik. Studiedesign: En kvalitativ intervjustudie innefattande fyra barnmorskor har genomförts på en barnmorskemottagning. Intervjumaterialet analyserades utifrån kvalitativ innehållsanalys, vilket i korthet innebar följande steg: Materialet transkriberades ordagrant och bröts därefter ned i meningsbärande enheter, för att kunna sortera data utifrån innehåll. Kondensering utfördes i syfte att lyfta fram kärninnehållet. Abstraktion utfördes för att få fram koder, i syfte att reducera mängden text men även för att därefter kunna sammanfoga snarlika ämnen till underkategorier, vilka sedan grupperades i huvudkategorier tillhörande ett gemensamt tema. Resultat: De fyra huvudkategorier som uppkom var känslor, kommunikation, rättighet och prevention. Känslor: Oro, stress samt nedstämdhet var vanligt förekommande. Mäns känslor var svårare att identifiera då kvinnor ibland kom ensamma till besöken, samt män ibland dolde känslor bakom aggressivitet. Kommunikation: God information skapade förtroende. Råd om livsstilsförändringar samt vidareremittering var en viktig form av stöd. Rättighet: Ingen har rätt till barn, men alla ansågs ha rätt att försöka få barn. Privatekonomi samt samhällets krav påverkar dock i stor utsträckning paren vid misslyckade försök eller önskan om ytterligare barn. Prevention: Vikten av information kring infertilitet vid undervisning i skolan, vid preventivmedelsamtal och vid cellprovtagning poängterades. Slutsats: Att vara väl införstådd med de känslor som kan uppstå i samband med infertilitet möjliggör att ge tillfredställande stöd. Särskilda ansträngningar behöver göras för att nå män, såväl emotionellt som preventivt. Stort utrymme för förbättring finns gällande preventiva åtgärder, i syfte att fördjupa allmänhetens kunskaper kring infertilitet. Nyckelord: kvinnlig infertilitet; manlig infertilitet; känslor; barnmorska; kvalitativ forskning / Abstract (English) Title: Infertility. Who´s right to decide? A qualitative interview study regarding midwives experiences to work with infertility. Author: Rebecka Kristensen Berlin, Umeå University- Department of nursing Objective: To investigate midwives thoughts and experiences regarding couples reactions in connection with infertility. Study design: A qualitative interview study comprising four midwives have been conducted. The resulting data was analyzed using qualitative content analysis, consisting of the following steps: The material was transcribed verbatim and then broken down into sentences, to aid in sorting the data based on content. Condensation was carried out in order to highlight the core content. Abstraction was performed to obtain codes, in order to reduce the amount of text , but also to subsequently merge similar content into subcategories , which were then grouped into categories. Results: Four main categories emerged. Feelings: anxiety, stress and depression were common. Men’s feelings were more difficult to identify since women sometimes came alone to appointments, and men sometimes concealed their feelings behind aggression. Communication: Good information created trust. Advice on lifestyle changes and referrals were important forms of support. Empowerment: No-one has the right to a child, but the right to try to have a child. Personal and societal demands, however, affect the couples at failure to conceive or desire for additional children. Prevention: The importance of information about fertility in school, at contraception counselling and routine smear exams was emphasized. Conclusion: Awareness of the feelings that infertility may give rise to, enables providing satisfactory support. Further efforts need to be made to reach males emotionally as well as preventatively. There is great possibility for improvement in regards to public awareness about infertility. Keywords: female infertility; male infertility; emotions; midwife; qualitative research
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Living through fertility loss: the experienceof Hong Kong Chinese women and men after in vitro fertilizationLee, Geok-ling., 李宜玲. January 2010 (has links)
published_or_final_version / Social Work and Social Administration / Doctoral / Doctor of Philosophy
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Impacts of pesticides exposure on semen characteristics among male farmers in Kienxuong district, Thaibinh province, Vietnam /Vu Phong Tuc, Voranuch Wangsuphachart, January 2007 (has links) (PDF)
Thesis (Ph.D. (Tropical Medicine))--Mahidol University, 2007. / LICL has E-Thesis 0025 ; please contact computer services. LIRV has E-Thesis 0025 ; please contact circulation services.
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The structure of the reproductive system in the male vervet monkey, Chlorocebus Aethiops, with special reference to spermatogenesis. /Lebelo, Segolo Lucky. January 2007 (has links) (PDF)
Thesis (Ph. D. (Dept. of Medical Biosciences)--University of the Western Cape, 2007. / Includes bibliographical references (leaves 215-239).
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Caracterização molecular do polimorfismo CAG e de mutações do gene do receptor de andrógeno em homens férteis e inférteis na região da Serra GaúchaFrassini, Rafaele 04 October 2010 (has links)
A espennatogênese é andrógeno-dependente, porém muitos homens com problemas na espermatogênese têm níveis hormonais androgênicos normais. O mau funcionamento do receptor de andrógenos (Androgen Receptor- AR) é a possível causa deste problema. O AR é membro da família dos receptores nucleares e é codificado pelo Gene do Receptor de Andrógenos, que é de cópia única, localizado no cromossomo X e possui oito éxons. O éxon 1 contém um segmento com repetições CAG, que codifica poliglutamina. O trato glutamínico é polimórfico e varia de 1 O a 35 repetições na população normal. Alterações no segmento CAG estão envolvidas na etiologia de doenças neurodegenerativas (repetições CAG > 40) e câncer de próstata (< a 16 repetições). Mutações no Gene do AR estão correlacionadas com a síndrome de insensibilidade aos andrógenos, que varia desde a completa feminilização até homens inférteis com fenótipo normal. O objetivo do presente estudo constituiu em investigar a correlação entre o polimorfismo CAG e a prevalência de mutações nos éxons 5 e 7 e a alteração dos parâmetros seminais na população da Serra Gaúcha. O segmento CAG e a região codificadora dos éxons 5 e 7 foram amplificadas pela técnica de reação da polimerase em cadeia (PCR) e analisadas pela técnica de seqüenciamento automatizado. A média das repetições CAG do grupo de pacientes (n = 45) foi de 20,04±3,94 e a média do grupo controle (n = 45) foi 20,64±3,71. Não há significânc:ia estatística entre elas (p = O, 459). Verificamos correlação entre as repetições CAG e a morfologia seminal (Organização Mundial da Saúde) (p = O, 032; r = O, 349). Porém não se verificou associação com os demais parâmetros seminais: concentração (p =O, 134; r= O, 227), motilidade (p = 0,184; r= 0,202), morfologia (Kruger) (p = 0,213; r= 0,210). Não foram detectadas mutações nos éxons 5 e 7 nos dois grupos de estudo. Nosso estudo sugere que polimorfismo CAG e a presença de mutações nos éxons 5 e 7 não estão correlacionados com alterações seminais no grupo de estudo. / Submitted by Ana Guimarães Pereira (agpereir@ucs.br) on 2015-09-22T16:54:58Z
No. of bitstreams: 1
Dissertacao Rafaele Frassini.pdf: 13123487 bytes, checksum: e567348e30bcf48846f22a5b5f684ada (MD5) / Made available in DSpace on 2015-09-22T16:54:58Z (GMT). No. of bitstreams: 1
Dissertacao Rafaele Frassini.pdf: 13123487 bytes, checksum: e567348e30bcf48846f22a5b5f684ada (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, CAPES. / Spermatogenesis is androgen-dependent, but most men with impaired spermatogenisis have normal serum androgens leveis. Malfunction of androgen receptor (AR) may be a possible cause of this problem. AR is a member of the nuclear receptor family. It encodes a single copy gene in the X chromosome. The AR Gene is composed by eigth exons. The exon 1 contains a segment of CAG repeats, translated to polyglutamine. This glutamine repeat tract is polymorphic and its size varies from 10 to 35 in normal population. These changes have clinicai implications for human diseases: neurodegenerative disorders (CAG repeat > 40) and prostate cancer (CAG repeat < 16). Mutations in AR Gene cause a variety of defects related to androgen insensitivity, ranging from complete feminization to phenotypic males with infertilty. The aim of this study was to investigate the relationship between CAG repeat length and the prevalence of mutations in the exon:s 5 and 7 and impaired spermatogenesis in a Serra Gaucha population. The CAG repeat leng1th and the coding region of exons 5 and 7 was amplified by polymerase chain reaction (PCR) and analyzed by direct DNA sequencing. The mean CAG repeat length in the experimental group (n = 45) was 20.04±3.94 and in the control group (n = 45) was 20.64±3.71. No difference was found between patientes and controls in the mean values (p = 0.459). 1We found relationship between CAG repeat and morphology (World Health Organization) (p = 0.032; r = 0.349). However, the correlation was not found between CAG repeat and others seminais parameters: concentration (p = 0.134; r= 0.227), morphology (Kruger) (p = 0.213;. r= 0.210) and motility (p = 0.184; r= 0.202). No mutations were detected in the coding regions of exons 5 and 7 in both groups. Our study suggests that CAG polymorphism and mutations in the exons 5 and 7 are not likely to cause of spermatogenesis abnnormalities in our population.
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Caracterização molecular do polimorfismo CAG e de mutações do gene do receptor de andrógeno em homens férteis e inférteis na região da Serra GaúchaFrassini, Rafaele 04 October 2010 (has links)
A espennatogênese é andrógeno-dependente, porém muitos homens com problemas na espermatogênese têm níveis hormonais androgênicos normais. O mau funcionamento do receptor de andrógenos (Androgen Receptor- AR) é a possível causa deste problema. O AR é membro da família dos receptores nucleares e é codificado pelo Gene do Receptor de Andrógenos, que é de cópia única, localizado no cromossomo X e possui oito éxons. O éxon 1 contém um segmento com repetições CAG, que codifica poliglutamina. O trato glutamínico é polimórfico e varia de 1 O a 35 repetições na população normal. Alterações no segmento CAG estão envolvidas na etiologia de doenças neurodegenerativas (repetições CAG > 40) e câncer de próstata (< a 16 repetições). Mutações no Gene do AR estão correlacionadas com a síndrome de insensibilidade aos andrógenos, que varia desde a completa feminilização até homens inférteis com fenótipo normal. O objetivo do presente estudo constituiu em investigar a correlação entre o polimorfismo CAG e a prevalência de mutações nos éxons 5 e 7 e a alteração dos parâmetros seminais na população da Serra Gaúcha. O segmento CAG e a região codificadora dos éxons 5 e 7 foram amplificadas pela técnica de reação da polimerase em cadeia (PCR) e analisadas pela técnica de seqüenciamento automatizado. A média das repetições CAG do grupo de pacientes (n = 45) foi de 20,04±3,94 e a média do grupo controle (n = 45) foi 20,64±3,71. Não há significânc:ia estatística entre elas (p = O, 459). Verificamos correlação entre as repetições CAG e a morfologia seminal (Organização Mundial da Saúde) (p = O, 032; r = O, 349). Porém não se verificou associação com os demais parâmetros seminais: concentração (p =O, 134; r= O, 227), motilidade (p = 0,184; r= 0,202), morfologia (Kruger) (p = 0,213; r= 0,210). Não foram detectadas mutações nos éxons 5 e 7 nos dois grupos de estudo. Nosso estudo sugere que polimorfismo CAG e a presença de mutações nos éxons 5 e 7 não estão correlacionados com alterações seminais no grupo de estudo. / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, CAPES. / Spermatogenesis is androgen-dependent, but most men with impaired spermatogenisis have normal serum androgens leveis. Malfunction of androgen receptor (AR) may be a possible cause of this problem. AR is a member of the nuclear receptor family. It encodes a single copy gene in the X chromosome. The AR Gene is composed by eigth exons. The exon 1 contains a segment of CAG repeats, translated to polyglutamine. This glutamine repeat tract is polymorphic and its size varies from 10 to 35 in normal population. These changes have clinicai implications for human diseases: neurodegenerative disorders (CAG repeat > 40) and prostate cancer (CAG repeat < 16). Mutations in AR Gene cause a variety of defects related to androgen insensitivity, ranging from complete feminization to phenotypic males with infertilty. The aim of this study was to investigate the relationship between CAG repeat length and the prevalence of mutations in the exon:s 5 and 7 and impaired spermatogenesis in a Serra Gaucha population. The CAG repeat leng1th and the coding region of exons 5 and 7 was amplified by polymerase chain reaction (PCR) and analyzed by direct DNA sequencing. The mean CAG repeat length in the experimental group (n = 45) was 20.04±3.94 and in the control group (n = 45) was 20.64±3.71. No difference was found between patientes and controls in the mean values (p = 0.459). 1We found relationship between CAG repeat and morphology (World Health Organization) (p = 0.032; r = 0.349). However, the correlation was not found between CAG repeat and others seminais parameters: concentration (p = 0.134; r= 0.227), morphology (Kruger) (p = 0.213;. r= 0.210) and motility (p = 0.184; r= 0.202). No mutations were detected in the coding regions of exons 5 and 7 in both groups. Our study suggests that CAG polymorphism and mutations in the exons 5 and 7 are not likely to cause of spermatogenesis abnnormalities in our population.
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Determination of in vitro effects of aqueous extract of camellia sinensis on human sperm functionsSetumo, Mmaphulane Abigail January 2021 (has links)
Thesis (M.Sc. (Medical Sciences)) -- University of Limpopo, 2021 / Infertility, defined as the inability to conceive following one year of unprotected sexual intercourse, respectively affects 25% of couples globally. Oxidative stress (OS) has been greatly related to the idiopathic cause of infertility and Camellia sinensis contains antioxidants that may enhance reproductive functions. This study focussed on the effects of Camellia sinensis (green and black tea) on human sperm functions in both normal and abnormal samples. Semen samples (n= 59) collected from donors were liquefied, analysed, and classified as normal (n=40) and abnormal (n= 19) using the WHO criteria. Samples were washed and exposed to aqueous leaf extracts of green and black tea (0, 0.4, 4, 40, 405 μg/ml) for 1 hour. Human Tubular Fluid (HTF) served as the control. The respective sperm parameters were analysed (sperm motility, vitality, DNA fragmentation, mitochondrial membrane potential (MMP), capacitation and acrosome reaction (CTC) and reactive oxygen species (ROS). Green and black tea significantly increased vitality, and intact MMP, while it significantly reduced, CTC, and intracellular ROS as well as DNA fragmented spermatozoa in both normal and abnormal samples compared to the control (p<0.05). A significant increase in sperm CTC, ROS, with a decrease in sperm vitality, and intact MMP was observed in the abnormal compared to the normal samples (p<0.05). No significant change in motility was observed between normal and abnormal samples compared to their respective controls, in both green and black tea (p>0.05). Camellia sinensis improved human sperm function in vitro and may be attributed to its antioxidant activity. / National Research Foundation (NRF)
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Effects of insulin and leptin on human spermatozoa function and their cross-talk with nitric oxide and cytokinesLampiao, Fanuel 12 1900 (has links)
Thesis (PhD (Biomedical Sciences. Medical Physiology))--University of Stellenbosch, 2009. / ENGLISH ABSTRACT: In recent years there has been an increase in obesity and diabetes mellitus (DM).
These conditions have for a long time been associated with infertility. Obesity is
characterized by high levels of circulating leptin and cytokines as well as insulin
resistance. Type I DM is associated with low or no insulin whereas, Type II DM is
characterised by insulin resistance. As the prevalence of obesity and DM continues
to rise, it is likely that the incidence of infertility associated with these pathological
conditions will likewise increase. The effects of insulin and leptin on male
reproductive function have been reported on the endocrine and spermatogenesis
level, but their effects on cellular level of human ejaculated spermatozoa are yet to
be elucidated.
This study presents data on the role of insulin and leptin on human ejaculated
spermatozoa and their interaction with cytokines and nitric oxide. In the first part of
the study, we established the suitable concentrations of glucose, insulin and leptin
that could be administered to human spermatozoa in vitro. Glucose concentration of
5.6 mM was chosen as the suitable concentration to be administered to human
spermatozoa because it has previously been reported in the literature; furthermore, it
is within the range of the physiological glucose levels found in the blood of fasting
humans. Insulin and leptin concentrations of 10 μIU and 10 nmol were chosen
respectively because they gave much improved sperm function and this was within
the range of insulin and leptin levels previously measured in human ejaculated
spermatozoa. This was followed by investigating the signalling pathway of insulin and
its beneficial effects on human spermatozoa function. Endogenous insulin secretion
from human ejaculated spermatozoa was blocked by nifedipine and its receptor
tyrosine phosphorylation effects were inhibited by erbstatin while phosphatidylinositol
3-kinase (PI3K) phosphorylation activity was inhibited by wortmannin. Exogenous
insulin administration significantly increased human sperm motility parameters as
well as the sperm ability to acrosome react. The inhibition of endogenous insulin
release from spermatozoa as well as the inhibition of the insulin receptor substrate
(IRS) tyrosine phosphorylation significantly decreased motility parameters and the
ability of spermatozoa to acrosome react.
The study also investigated the effects of insulin and leptin on human sperm motility,
viability, acrosome reaction and nitric oxide (NO) production. Both insulin and leptin
significantly increased sperm motility parameters, acrosome reaction and NO
production. The NO production induced by insulin and leptin was via PI3K signalling
as evidenced by a reduction in NO levels when PI3K activity was inhibited by
wortmannin. To investigate whether insulin and leptin could improve motility
parameters of asthernozoospermic and teratozoospermic spermatozoa, the
spermatozoa were separated into two fractions by means of a double density
gradient technique. The gradient system was able to separate spermatozoa into high
morphologically abnormal and less motile spermatozoa similar to that of
asthernozoospermic and teratozoospermic patients as well as a more motile fraction.
Insulin and leptin significantly increased the motility parameters of spermatozoa from
the immature and less motile fraction.
The fourth part of the study was aimed at investigating the effects of the cytokines,
tumor necrosis factor alpha (TNF-α) and interleukin-6 (IL-6), on human sperm
motility, viability, acrosome reaction and NO production. The study shows that TNF-α
and IL-6 significantly reduced motility parameters and acrosome reaction in a dose4
and time-dependent manner. These cytokines were also shown to significantly
increase NO production from human spermatozoa. The decreased motility
parameters induced by these cytokines could be attributed to their ability to induce
excessive NO production. It is not yet clear how they inhibit spermatozoa to undergo
the acrosome reaction.
The fifth part of the study was to investigate the expression and localization of
glucose transporter 8 (GLUT8) in human spermatozoa. This study shows that GLUT8
is constitutively expressed and located in the midpiece region of the human
spermatozoa. The study also showed that stimulating spermatozoa with insulin led to
an increase in GLUT8 expression as well as translocation to the acrosomal region.
In the last part of the study we wanted to investigate why the increase in NO
generation by spermatozoa due to insulin and leptin stimulation is accompanied with
increased sperm function whereas NO increased due to TNF-α and IL-6 stimulation
is accompanied with decreased sperm function. We observed that TNF-α and IL-6
not only increased NO production but also ROS production. This study speculates
that the decrease in sperm motility and acrosome reaction when TNF-α and IL-6
were administered was due to the concomitant high increase in NO and ROS they
induced.
In conclusion, this study has established in vitro beneficial effects of insulin and leptin
in normozoospermic and asthernozoospermic human sperm function. These
hormones influence sperm function via the PI3K signalling pathway in two ways.
Firstly, by increasing GLUT8 expression and translocation thereby possibly
increasing glucose uptake and metabolism and secondly, by increasing NO
production. The study has also established that TNF-α and IL-6 have detrimental
effects on human spermatozoa in a dose and time dependent manner. These effects
are mediated via their ability to stimulate both NO and ROS production in human
spermatozoa. This study reports that GLUT8 is expressed in the midpiece region of
human spermatozoa and that insulin stimulation upgrades its expression and leads to
its translocation to the acrosomal region. / AFRIKAANSE OPSOMMING: Oor die afgelope jare was daar `n toename in obesiteit en diabetes mellitus (DM).
Hierdie toestande word reeds vir ’n geruime tyd geassosieer met onvrugbaarheid.
Obesiteit word gekenmerk deur verhoogde sirkulerende vlakke van leptiene en
sitokiene sowel as insulien weerstandigheid. Tipe I DM word geassosieer met lae of
geen insulien terwyl Tipe II DM gekenmerk word deur insulien weerstandigheid. Soos
wat die voorkoms van obesiteit en DM toeneem, is dit waarskynlik dat die insidensie
van onvrugbaarheid wat met hierdie patologiese toestande geassosieer word,
gevolglik ook sal toeneem. Die effek van insulien en leptien op die manlike
voortplantingsfunksie is alreeds aangetoon op endokriene en spermatogenese vlak,
maar hul effekte op sellulêre vlak van menslike geëjakuleerde spermatosoë is nog
onduidelik.
Die studie vertoon data oor die rol van insulien en leptien op die menslike
geëjakuleerde spermatosoë en hul interaksie met sitokiene en stikstofoksied (NO). In
die eerste gedeelte van die studie, het ons ’n toepaslike konsentrasie van insulien en
leptien bepaal wat aan menslike spermatosoë in vitro toegedien kan word. Glukose
konsentrasies van 5,6 mM is bepaal as die gepaste konsentrasie om aan menslike
spermatosoë toe te dien, omdat dit beter resultate tot gevolg het; verder is dit
vergelykbaar met fisiologiese glukose vlakke in die bloed van `n vastende persoon.
Insulien en leptien konsentrasies is op 10 μIU en 10 nm onderskeidelik vasgestel,
aangesien dit tot beter resultate gelei het, en omdat dit vergelykbaar was met
insulien en leptien vlakke wat reeds voorheen in menslike geëjakuleerde
spermatosoë gemeet is. Dit was gevolg deur `n ondersoek na die insulien
seintransduksie pad en sy voordelige effekte op menslike spermatosoë funksie.
Endogene insulien afskeiding deur menslike geëjakuleerde spermatosoë was deur
nifedipien geïnhibeer en sy reseptor tirosien fosforilasie effekte was deur erbstatin
geïnhibeer terwyl fosfatidielinositol 3-kinase (PI3K) fosforilasie deur wortmannin
geïnhibeer is. Eksogene insulien toediening het menslike sperm-motiliteit parameters
betekenisvol laat toeneem asook die vermoë van sperme om die akrosoomreaksie te
ondergaan. Die inhibisie van endogene insulien afskeiding deur spermatosoë sowel
as die inhibisie van die insulien reseptor substraat (IRS) tirosien fosforilasie het die
motiliteit parameters en die akrosoomreaksievermoë van spermatosoë verlaag.
Die studie het ook die effekte van insulien en leptien op menslike sperm-motiliteit,
-lewensvatbaarheid, -akrosoomreaksie en -NO produksie nagevors. Beide insulien
en leptien het sperm-motiliteit parameters, -akrosoomreaksie en -NO produksie
betekenisvol verhoog. NO produksie is deur insulien en leptien via PI3K
seintransduksie geïnduseer, soos bewys deur die verlaging waargeneem in NO
vlakke toe PI3K aktiwiteit deur wortmannin geïnhibeer was. Om vas te stel of insulien
en leptien die motiliteit parameters van asthenozoospermiese en teratozoospermiese
spermatosoë kon verbeter, het ons spermatosoë in twee fraksies met ’n dubbel
digtheid gradiënt geskei. Die gradiënt sisteem was daartoe instaat om die
spermatosoë in ’n onvolwasse, (morfologies abnormaal en minder motiel - soortgelyk
aan dié van asthenozoospermiese en teratozoospermiese pasiënte), sowel as ’n
volwasse meer motiele fraksie te skei. Insulien en leptien het die motiliteit parameters
van spermatosoë van die onvolwasse en minder motiele fraksie verhoog.
Die vierde gedeelte van die studie was daarop gemik om die effekte van die sitokiene
tumor nekrose faktor alfa (TNF-α) en interleukin-6 (IL-6) op menslike sperm-motiliteit,
-lewensvatbaarheid, -akrosoomreaksie en -NO produksie, te ondersoek. Die studie
het getoon dat TNF-α en IL-6 motiliteit parameters en akrosoomreaksie in ’n tyd- en
dosis-afhanklike wyse betekenisvol verlaag het. Hierdie sitokiene was ook in staat
om NO produksie in menslike spermatosoë te verhoog. Die verlaging in motiliteit
parameters wat deur hierdie sitokiene geïnduseer is, kan toegeskryf word aan hul
vermoë om die produksie van oormatige hoeveelhede NO te stimuleer. Dit is nog nie
duidelik hoe hulle die akrosoomreaksie in spermatosoë kan inhibeer nie.
Die vyfde gedeelte van die studie het dit ten doel gehad om die uitdrukking en
lokalisering van die glukose transporter 8 (GLUT8) in menslike spermatosoë te
ondersoek. Hierdie studie kon aantoon dat GLUT8 konstitutief uitgedruk is en in die
middelstuk van die menslike spermatosoë voorkom. Die studie bewys ook dat
stimulering van die spermatosoë met insulien tot `n toename in GLUT8 uitdrukking
sowel as translokasie na die akrosomale area, lei.
In die finale gedeelte van die studie wou ons ondersoek waarom die toename in NO
produksie in spermatosoë (as gevolg van insulien en leptien stimulasie) deur `n
toename in spermfunksie gekenmerk word, terwyl die toename in NO produksie (as
gevolg van TNF-α en IL-6 stimulasie) deur ’n afname in spermfunksie gekenmerk
word. Ons het waargeneem dat TNF-α en IL-6 nie alleen NO produksie nie, maar ook
reaktiewe suurstof spesies (ROS) produksie verhoog het. Ons vermoed dat die
afname in sperm motiliteit en akrosoomreaksie met TNF-α en IL-6 toediening, die
gevolg van die gelyktydige verhoging in NO en ROS was.
In gevolgtrekking kan ons sê dat hierdie studie die voordelige in vitro effekte van
insulien en leptien op asthenozoospermiese en teratozoospermiese menslike
spermfunksie aangetoon het. Hierdie hormone beïnvloed spermfunksie via die PI3K
seintransduksie pad op twee maniere. Eerstens, deur `n toename in GLUT8
uitdrukking en translokasie, met die gevolg dat glukose opname en metabolisme
moontlik verhoog is, en tweedens, deur die toename in NO produksie. Die studie het
ook vasgestel dat TNF-α en IL-6 nadelige effekte op menslike spermatosoë in `n
dosis- en tyd-afhanklike wyse het. Hierdie effekte vind plaas a.g.v. hul vermoë om
beide NO en ROS produksie in menslike spermatosoë te induseer. Die studie toon
aan dat GLUT8 uitdrukking in die middelstuk van die menslike spermatosoon
voorkom en dat insulien stimulasie GLUT8 uitdrukking opreguleer en tot translokasie
na die akrosomale area lei.
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