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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.
11

Papel protetor da infusão do chá verde sobre o dano induzido pela ciclofosfamida no sistema reprodutor de camundongos / Protective role of the green tea infusion on damage cyclophosphamide-induced on reproductive system of mice

Zanchi, Mariane Magalhães 26 July 2014 (has links)
Submitted by Marcos Anselmo (marcos.anselmo@unipampa.edu.br) on 2016-04-18T17:36:59Z No. of bitstreams: 1 MARIANE MAGALHÃES ZANCHI.pdf: 1185149 bytes, checksum: 5b02afd42e868819a353f05a3e1fb99a (MD5) / Made available in DSpace on 2016-04-18T17:36:59Z (GMT). No. of bitstreams: 1 MARIANE MAGALHÃES ZANCHI.pdf: 1185149 bytes, checksum: 5b02afd42e868819a353f05a3e1fb99a (MD5) Previous issue date: 2014-07-26 / A ciclofosfamida (CF) é um agente antineoplásico e imunossupressor, usada no tratamento de diversos tipos de tumores e em algumas doenças auto-imunes. A CF é considerada um pró-fármaco, portanto, precisa sofrer biotransformação hepática para formar seus metabólitos ativos, como a mostarda fosforamida e a acroleína. Seu metabólito terapêutico, a mostarda fosforamida, é responsável pelo efeito citotóxico na célula tumoral, enquanto a acroleína é conhecida por apresentar um efeito tóxico secundário, por aumentar a produção de espécies reativas ao oxigênio, causando estresse oxidativo. Esse, por sua vez, poderia estar diretamente relacionado com a redução da fertilidade causada por esta droga. Diante disso, compostos naturais com atividade antioxidante poderiam ser uma alternativa ao dano causado pela CF. O chá verde, obtido da planta Camellia sinensis, tem ação antioxidante e scavenger de radicais livres, devido ao alto conteúdo de polifenóis. O presente estudo avalia o papel protetor da infusão do chá verde sobre o dano oxidativo no sistema reprodutor de camundongos machos, e a sua relação com a fertilidade, após uma administração aguda de CF. Os camundongos foram pré-tratados por gavagem com veículo ou chá verde diariamente, por 14 dias, na dose de 250 mg/kg. A CF foi administrada via intraperitoneal no 14o dia, 1 hora após a administração do chá, na dose de 100 mg/kg. Os camundongos foram eutanasiados 24 horas após a administração da CF, e os testículos e epidídimos foram retirados para posteriores análises bioquímicas e avaliação espermática. O conteúdo de catequinas, principais constituintes do chá verde foi avaliada por HPLC. Epigalocatequina galato (EGCG) está presente em alta concentração na nossa infusão (1340,2 μg/mL), seguido por epicatequina (EC-500,95 μg/mL) e epicatequina galato (ECG-302,84 μg/mL). CF causou estresse oxidativo no sistema reprodutor dos animais, evidenciado neste trabalho por danificar tanto lipídios, como proteínas e DNA. A CF causou um aumento na peroxidação lipídica (níveis de MDA), dano de DNA (ensaio cometa) e atividade da enzima superóxido dismutase (SOD), enquanto diminuiu a atividade da glutationa peroxidase (GPx), glutationa-S-transferase (GST) e 17β–hidroxiesteróide desidrogenase (17β–HSD) em ambos os tecido testados. A atividade da enzima catalase (CAT) e a quantificação de proteína carbonil foram alteradas somente em testículo, mas não em epidídimo. Em relação à avaliação espermática, CF reduziu significativamente apenas a concentração de espermatozóides, comparado ao controle. O pré-tratamento com a infusão do chá verde reduziu significativamente a produção de MDA, carbonilação de proteína, dano de DNA e restaurou a atividade da GPx e GST. Em epidídimo, o chá verde também aumentou a concentração espermática e restaurou a atividade da enzima 17β–HSD. Pode-se concluir que a infusão do chá verde melhora o dano induzido pela CF, no sistema reprodutor de camundongos, e este efeito poderia ser atribuído ao alto conteúdo de catequinas presentes no chá e à sua atividade antioxidante. / Cyclophosphamide (CP) is an antineoplastic and immunosuppressive agent used to treat various types of tumors and in some autoimmune diseases. CP is considered a prodrug, therefore, must undergo hepatic biotransformation to form its active metabolites, such as phosphoramide mustard and acrolein. Its therapeutic metabolite, phosphoramide mustard, is responsible for the cytotoxic effect on tumor cells, while acrolein is known to provide a secondary toxic effect by increasing the reactive oxygen species production, causing oxidative stress. This might be directly related to the fertility reduction caused by this drug. Therefore, natural compounds with antioxidant activity could be an alternative to the damage caused by CP. Green tea, obtained from the plant Camellia sinensis, has antioxidant and free radical scavenging effect, due to the high content of polyphenols. The present study evaluates the protective role of the green tea infusion on oxidative damage on male mice reproductive system, and their relationship to fertility after an acute administration of CP. The mice were pre-treated by gavage with vehicle or green tea daily for 14 days at dose of 250 mg/kg. CP was administered intraperitoneally on day 14, 1 hour after administration of tea at dose of 100 mg/kg. Mice were euthanized 24 hours after the administration of the CP and testes and epididymis were removed for further biochemical analysis and sperm assessment. The content of catechins, the main constituents of green tea were evaluated by HPLC. Epigallocatechin gallate (EGCG) is present in high concentrations in our infusion (1340.2 μg/ml), followed by epicatechin (EC-500.95 μg/ml) and epicatechin gallate (ECG-302.84 μg/mL). CP caused oxidative stress in the reproductive system of animals, evidenced in this work by damaging not only lipids, but also proteins and DNA. CP increased lipid peroxidation (MDA), DNA damage (comet assay) and superoxide dismutase (SOD) activity, while decreased glutathione peroxidase (GPx), glutathione-S-transferase (GST) and 17β-hydroxysteroid dehydrogenase (17β-HSD) activity in both tissues tested. Catalase (CAT) activity and quantification of protein carbonyl were altered only in testes but not in the epididymis. Regarding sperm evaluation, CF significantly decreased only sperm concentration, compared to the control group. Pre-treatment with green tea infusion significantly reduced MDA production, protein carbonylation, DNA damage and restored GPx and GST activity. In epididymis, green tea also increased sperm concentration and restored 17 β-HSD activity. Green tea infusion improves the damage induced by CP in the reproductive system of mice, and this effect is attributed to the high content of catechins in tea and its antioxidant activity.
12

Avaliação do potencial protetor do extrato seco de Tribulus terrestris sobre o dano induzido por ciclofosfamida no sistema reprodutor masculino de camundongos / Assessment of the potential protector effect of Tribulus terrestris dry extract on cyclophosphamide-induced damage to male mice reproductive system

Pavin, Natasha Frasson 02 April 2016 (has links)
Submitted by Marcos Anselmo (marcos.anselmo@unipampa.edu.br) on 2016-05-02T13:45:06Z No. of bitstreams: 1 Natasha Pavin.pdf: 478428 bytes, checksum: 248a3efadd02d2695494d5e6ef077e2b (MD5) / Made available in DSpace on 2016-05-02T13:45:07Z (GMT). No. of bitstreams: 1 Natasha Pavin.pdf: 478428 bytes, checksum: 248a3efadd02d2695494d5e6ef077e2b (MD5) Previous issue date: 2016-04-02 / A ciclofosfamida (CP) é um agente antineoplásico e imunossupressor. É uma droga utilizada no tratamento de diversos tipos de tumores, usada para evitar a rejeição em transplante de órgãos e em doenças autoimunes, como artrite reumática e lúpus eritematoso. A CP é um pró-fármaco que sofre biotransformação no fígado pelo citocromo P450 para gerar metabólitos ativos como a mostarda fosfaramida e a acroleína. Seus metabólitos podem ocasionar um quadro de estresse oxidativo causando danos a diversos órgãos, entre eles o sistema reprodutor. A Tribulus terrestris (TT) faz parte da família das Zygophyllaceae, é uma erva rasteira perene com uma distribuição generalizada no Mediterrâneo, climas subtropicais e no deserto de todo o mundo. Na medicina popular tradicional, tem sido utilizada desde a antiguidade como um afrodisíaco, para energizar, vitalizar e melhorar a função sexual e desempenho físico em homens, bem como para tratar infecções urinárias, inflamações, edemas e outras doenças. Apesar de estudos experimentais e clínicos confirmarem parcialmente o fato de alguns efeitos da TT sobre a libido e a produção de esperma estarem envolvidos com o componente majoritário desta planta, a protodioscina, ainda há muito debate a respeito dos possíveis mecanismos de ação, bem como da sua aplicação terapêutica. Considerando o potencial antioxidante e esteroidogênico da TT, este estudo possui como objetivo investigar o potencial protetor do extrato seco da TT contra o dano testicular induzido pela ciclofosfamida em camundongos machos. Os camundongos Swiss machos receberam o extrato seco de TT como pré-tratamento por gavagem, durante 14 dias, na dose de 11 mg/Kg. No 14 ° dia, receberam uma única injeção intraperitoneal de ciclofosfamida na dose de 100 mg/Kg. Após 24 horas, esses animais foram anestesiados e eutanasiados, e o sangue, os testículos e os epidídimos foram retirados para posteriores análises bioquímicas, avaliação espermática e histopatológica. A presença e quantificação de protodioscina no vii extrato de TT foram avaliadas por HPLC (Cromatografia Líquida de Alta Eficiência), onde foi verificada uma concentração de 1,48% no extrato seco. A CP causou um desequilíbrio no sistema reprodutor destes animais, através do aumento das espécies reativas (ER), peroxidação lipídica (TBARS) e carbonilação de proteínas, bem como uma alteração nas enzimas antioxidantes: superóxido dismutase (SOD), catalase (CAT), glutationa peroxidase (GPx), glutationa S-transferase (GST) e glutationa redutase (GR). O pré tratamento com TT foi eficaz em proteger contra esses danos. Além disso, foi verificado uma redução na atividade da enzima 17β-hidroxiesteróide desidrogenase (17β-HSD), corroborando com a redução do nível de testosterona sérica verificado neste trabalho. Ao mesmo tempo, ao analisarmos a histopatologia dos testículos destes animais, verificamos uma moderada desorganização do epitélio espermatogenico, bem como, uma congestão dos vasos sanguíneos intersticiais. Estes achados corroboraram com os resultados encontrados na avaliação seminal dos animais tratados com CP, onde foi possível verificar uma diminuição da motilidade (41,07%), do vigor (23,52%), da integridade de membrana (43,44%) e da velocidade curvo-retilinea (25,43%), e o pré tratamento com TT foi eficaz em proteger contra esses danos. Em conclusão, este trabalho visou demonstrar pela primeira vez o potencial protetor do extrato seco de TT contra os danos ao sistema reprodutor masculino de camundongos expostos ao quimioterápico CP. À melhora dos parâmetros avaliados pode estar relacionada ao potencial antioxidante e esteroidogênico, bem como pela quantidade de protodioscina observada neste extrato. / Cyclophosphamide (CP) is an antineoplastic and immunosuppressive agent. It is a drug used to treat various tumours types, and also to prevent rejection in organ transplantation and autoimmune diseases such as rheumatoid arthritis and lupus erythematosus. The CP is a prodrug which is biotransformed in the liver by cytochrome P450 enzymes to generate active metabolites phosphoramide mustard and acrolein. Its metabolites can cause oxidative stress state, leading to damage in various organs, including the reproductive system. Tribulus terrestris (TT) is part of the family of Zygophyllaceae, it is a perennial creeping herb with a widespread distribution in the Mediterranean, subtropical climates and desert around the world. In traditional folk medicine, it has been used since ancient times as an aphrodisiac, to energize, vitalize and improve sexual function and physical performance in men and to treat urinary infections, inflammation, edema and other diseases. Although experimental and clinical studies partly confirm that some effects of TT on libido and sperm production are involved with the major component of this plant, protodioscin, there is still much debate about the possible mechanisms of action, as well as their therapeutic application. Considering the antioxidant and steroidogenic potential of TT, this study has the objective of investigating the protective potential of TT dry extract against testicular damage induced by cyclophosphamide in male mice. The male Swiss mice received the TT dry extract as pretreatment by gavage for 14 days at a dose of 11 mg kg-1. On day 14, animals received a single intraperitoneally injection of cyclophosphamide at a dose of 100 mg kg-1. After 24 hours, the animals were anesthetized and euthanized, and blood, testes and epididymis were removed for further biochemical analyzes, sperm and histological evaluation. The presence and quantification of protodioscin in TT extract were analyzed by HPLC (High Performance Liquid Chromatography), where a concentration of 1.48% of dry extract was verified. CP caused an imbalance in the reproductive system of these animals by increasing the reactive species (RS), ix lipid peroxidation (TBARS) and protein carbonylation, as well as change in antioxidant enzymes: superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione S-transferase (GST) and glutathione reductase (GR). The pre-treatment with TT was effective in protecting against this damage. Furthermore, a reduction in the activity of 17β-hydroxysteroid dehydrogenase (17β-HSD) was found, confirming the reduction of serum testosterone levels observed in this study. Additionally, when analyzing the histopathology of the animals’ testes, we perceived a moderate disruption of spermatogenesis epithelium, as well as a congestion of interstitial blood vessels. These findings corroborate the results found in seminal evaluation of the animals treated with CP, where we observed a decrease in motility (41.07%), vigor (23.52%), membrane integrity (43,44%) and curved-straight speed (25.43%), and the pre-treatment with TT was effective in protecting against this damage. In conclusion, this study aimed to demonstrate for the first time the protective potential of TT dry extract against damage to the male reproductive system of mice exposed to CP chemotherapy. Improvement of these parameters may be related to antioxidant and steroidogenic potential as well as the amount of protodioscin observed in this extract.
13

The implementation of in vitro assays to screen environmental samples for male reproductive toxicity

Ebrahim, Mozaffar January 2010 (has links)
Magister Scientiae (Medical Bioscience) - MSc(MBS) / Endocrine disrupting compounds (EDCs) are exogenous compounds/chemicals which interfere with, or have adverse effects on the production, distribution and function of natural hormones, thereby affecting normal endocrine activity, health and quality of life of both humans and wildlife. The reproductive system is highly susceptible to EDCs due to it being controlled by an array of hormonal signals. The effects of EDCs on the male reproductive system include infertility, decreased sperm count, function and morphology, abnormal development of secondary sex characteristics, reproductive function and sexual behaviour as well as decreased libido. There are various sources by which EDCs enter the environment which include effluents from several industries (mining, agriculture, smelting, hazardous waste sites, manufacturing industries, etc.), sewage treatment effluents, urban and agricultural runoff and effluents which include natural and pharmaceutical chemicals excreted in the urine of humans and domestic livestock, pesticides, polychlorinated biphenyls, dioxins, plasticizers, surfactants, etc. Humans and animals can also be affected by EDCs by consuming food containing endocrine active substances. The growing concern regarding adverse effects due to EDC exposure of humans and wildlife, as well as the increased incidence of EDC contamination has prompted extensive research into the development and validation of screening tests to detect and monitor known EDCs and new substances with endocrine-disrupting capability. These screening tests involve assessing the effect of known and potential EDCs on reproductive function and development as well as hormone production. To assess the effect of EDCs on the reproductive system different methods are employed which include in vitro, in vivo and ex vivo methods. In vitro methods have been suggested as a suitable screening tool for EDC monitoring due to low costs, reduced animal usage, the use of standard and basic equipment as well as the ability to screen a large number of samples with multiple endpoints. Of the available in vitro methods, the minced testes method has been suggested as the most suitable method for screening EDCs and for this reason has been employed in this study. The aim of this study was thus to employ a minced testes method to screen samples for male reproductive toxicity using cell viability and hormone production (testosterone and estradiol) as endpoints.The first objective of this study was to optimize an in vitro testicular cell culture assay by determining both optimal luteinizing hormone (LH)  concentration and incubation time needed for testosterone production. Testicular cell cultures were prepared and cells were treated with varying concentrations of LH (10, 1, 0.1, 0.01 and 0 mu/ml) and incubated for 4 hours and 20 hours. Testosterone production was evaluated for each incubation period. Testosterone production was significantly increased for both incubation periods at all LH concentrations tested as compared to the control. For both incubation periods, there was no significant difference in testosterone production between the different LH concentrations tested. From the data obtained, the 4 hour incubation period as well as the LH concentration of 10 mu/ml were selected as optimal for the testicular cell culture assay. The second objective of this study was to determine the effect of Tulbaghia violacea Harv. on the male reproductive system. T. violacea is a plant species indigenous to southern Africa and is used locally as a herbal remedy/medicine to treat several ailments. Cells were treated with varying concentrations of the T. violacea ethanol extract (with/without LH-treatment) and incubated for 4 hours. Hormone production and cell viability were evaluated. The results obtained from this pilot in vitro study demonstrated that the ethanol extract of T.violacea has androgenic properties by significantly increasing LH-induced testosterone production in mouse testes with no significant change in cell viability. The third objective of this study was to assess the effect of Sutherlandia frutescens(L.) R.Br and Artemisia afra Jacq. Ex Willd. on the male reproductive system. S. frutescens and A. afra are also plant species indigenous to southern Africa and used locally as a herbal remedy/medicine to treat several ailments. Ethanol extracts of each plant was prepared and cells were treated with varying concentrations of each extract (0, 156.25, 312.5, 625, 1250,2500 and 5000 μg/ml) with or without LH-treatment and incubated for 4 hours. Cytotoxicity by LDH measurement and hormone production (testosterone and estradiol) were endpoints that were evaluated. The results obtained showed that the ethanol extracts of both plants are not cytotoxic to testicular cells and that A. afra decreases testosterone production at high concentrations. The fourth and final objective of this study was to assess the acute effect of four heavy metals, namely manganese, copper, cadmium and magnesium on the male reproductive system. These heavy metals are used extensively in manufacturing and mining industries. Cells were treated with varying concentrations of each metal salt (200, 100, 50, 25, 12.5, and 6.25 & mu;M) with or without LH-treatment and incubated for 4 hours. Endpoints evaluated included cell viability, testosterone and estradiol production. The results obtained showed that manganese, cadmium and copper are highly toxic to testicular cells in vitro and therefore may potentially cause reproductive toxicity. / South Africa
14

The implementation of in vitro assays to screen environmental samples for male reproductive toxicity

Ebrahim, Mozaffar January 2010 (has links)
<p>Endocrine&ndash / disrupting compounds (EDCs) are exogenous compounds/chemicals which interfere with, or have adverse effects on the production, distribution and function of natural hormones, thereby affecting normal endocrine activity, health and quality of life of both humans and wildlife. The reproductive system is highly susceptible to EDCs due to it being controlled by an array of hormonal signals. The effects of EDCs on the male reproductive system include infertility, decreased sperm count, function and morphology, abnormal development of secondary sex characteristics, reproductive function and sexual behaviour as well as decreased libido. There are various sources by which EDCs enter the environment which include effluents from several industries (mining, agriculture, smelting, hazardous waste sites, manufacturing industries, etc.), sewage treatment effluents, urban and agricultural runoff and effluents which include natural and pharmaceutical chemicals excreted in the urine of humans and domestic livestock, pesticides, polychlorinated biphenyls, dioxins, plasticizers, surfactants, etc. Humans and animals can also be affected by EDCs by consuming food containing endocrine active substances. The growing concern regarding adverse effects due to EDC exposure of humans and wildlife, as well as the increased incidence of EDC contamination has prompted extensive research into the development and validation of screening tests to detect and monitor known EDCs and new substances with endocrine-disrupting capability. These screening tests involve assessing the effect of known and potential EDCs on reproductive function and development as well as&nbsp / hormone production. To assess the effect of EDCs on the reproductive system different methods are employed which include in vitro, in vivo and ex vivo methods. In vitro methods have been suggested as a suitable screening tool for EDC monitoring due to low costs, reduced animal usage, the use of standard and basic equipment as well as the ability to screen a large number of samples with multiple endpoints. Of the available in vitro methods, the minced testes method has been suggested as the most suitable method for screening EDCs and for this reason has been employed in this study. The aim of this study was thus to employ a minced testes method to screen samples for male reproductive toxicity using cell viability and hormone production (testosterone and estradiol) as endpoints.The first objective of this study was to optimize an in vitro testicular cell culture assay by determining both optimal luteinizing hormone (LH)&nbsp / concentration and incubation time needed for testosterone production. Testicular cell cultures were prepared and cells were treated with varying concentrations of LH (10, 1, 0.1, 0.01 and 0 mu/ml) and incubated for 4 hours and 20 hours. Testosterone production was evaluated for each incubation period. Testosterone production was significantly increased for both incubation periods at all LH concentrations tested as compared to the control. For both incubation periods, there was no significant difference in testosterone production between the different LH concentrations tested. From the data obtained, the 4 hour incubation period as well as the LH concentration of 10 mu/ml were selected as optimal for the testicular cell culture assay. The second objective of this study was to determine the effect of Tulbaghia violacea Harv. on the male reproductive system. T. violacea is a plant species indigenous to southern Africa and is used locally as a herbal remedy/medicine to treat several ailments. Cells were treated with varying concentrations of the T. violacea ethanol extract (with/without LH-treatment) and incubated for 4 hours. Hormone production and cell viability were evaluated. The results obtained from this pilot in vitro study demonstrated that the ethanol extract of T.violacea has androgenic properties by significantly increasing LH-induced testosterone production in mouse testes with no significant change in cell viability. The third objective of this study was to assess the effect of Sutherlandia frutescens(L.) R.Br and Artemisia afra Jacq. Ex Willd. on the male reproductive system. S. frutescens and A. afra are also plant species indigenous to southern Africa and used locally as a herbal remedy/medicine to treat several ailments. Ethanol extracts of each plant was prepared and cells were treated with varying concentrations of each extract (0, 156.25, 312.5, 625, 1250,2500 and 5000 &mu / g/ml) with or without LH-treatment and incubated for 4 hours. Cytotoxicity by LDH measurement and hormone production (testosterone and estradiol) were endpoints that were evaluated. The results obtained showed that the ethanol extracts of both plants are not cytotoxic to testicular cells and that A. afra decreases testosterone production at high concentrations. The fourth and final objective of this study was to assess the acute effect of four heavy metals, namely manganese, copper, cadmium and magnesium on the male reproductive system. These heavy metals are used extensively in manufacturing and mining industries. Cells were treated with varying concentrations of each metal salt (200, 100, 50, 25, 12.5, and 6.25&nbsp / &mu / M) with or without LH-treatment and incubated for 4 hours. Endpoints evaluated included cell viability, testosterone and estradiol production. The results obtained showed that manganese, cadmium and copper are highly toxic to testicular cells in vitro and therefore may potentially cause reproductive toxicity.</p>
15

The implementation of in vitro assays to screen environmental samples for male reproductive toxicity

Ebrahim, Mozaffar January 2010 (has links)
<p>Endocrine&ndash / disrupting compounds (EDCs) are exogenous compounds/chemicals which interfere with, or have adverse effects on the production, distribution and function of natural hormones, thereby affecting normal endocrine activity, health and quality of life of both humans and wildlife. The reproductive system is highly susceptible to EDCs due to it being controlled by an array of hormonal signals. The effects of EDCs on the male reproductive system include infertility, decreased sperm count, function and morphology, abnormal development of secondary sex characteristics, reproductive function and sexual behaviour as well as decreased libido. There are various sources by which EDCs enter the environment which include effluents from several industries (mining, agriculture, smelting, hazardous waste sites, manufacturing industries, etc.), sewage treatment effluents, urban and agricultural runoff and effluents which include natural and pharmaceutical chemicals excreted in the urine of humans and domestic livestock, pesticides, polychlorinated biphenyls, dioxins, plasticizers, surfactants, etc. Humans and animals can also be affected by EDCs by consuming food containing endocrine active substances. The growing concern regarding adverse effects due to EDC exposure of humans and wildlife, as well as the increased incidence of EDC contamination has prompted extensive research into the development and validation of screening tests to detect and monitor known EDCs and new substances with endocrine-disrupting capability. These screening tests involve assessing the effect of known and potential EDCs on reproductive function and development as well as&nbsp / hormone production. To assess the effect of EDCs on the reproductive system different methods are employed which include in vitro, in vivo and ex vivo methods. In vitro methods have been suggested as a suitable screening tool for EDC monitoring due to low costs, reduced animal usage, the use of standard and basic equipment as well as the ability to screen a large number of samples with multiple endpoints. Of the available in vitro methods, the minced testes method has been suggested as the most suitable method for screening EDCs and for this reason has been employed in this study. The aim of this study was thus to employ a minced testes method to screen samples for male reproductive toxicity using cell viability and hormone production (testosterone and estradiol) as endpoints.The first objective of this study was to optimize an in vitro testicular cell culture assay by determining both optimal luteinizing hormone (LH)&nbsp / concentration and incubation time needed for testosterone production. Testicular cell cultures were prepared and cells were treated with varying concentrations of LH (10, 1, 0.1, 0.01 and 0 mu/ml) and incubated for 4 hours and 20 hours. Testosterone production was evaluated for each incubation period. Testosterone production was significantly increased for both incubation periods at all LH concentrations tested as compared to the control. For both incubation periods, there was no significant difference in testosterone production between the different LH concentrations tested. From the data obtained, the 4 hour incubation period as well as the LH concentration of 10 mu/ml were selected as optimal for the testicular cell culture assay. The second objective of this study was to determine the effect of Tulbaghia violacea Harv. on the male reproductive system. T. violacea is a plant species indigenous to southern Africa and is used locally as a herbal remedy/medicine to treat several ailments. Cells were treated with varying concentrations of the T. violacea ethanol extract (with/without LH-treatment) and incubated for 4 hours. Hormone production and cell viability were evaluated. The results obtained from this pilot in vitro study demonstrated that the ethanol extract of T.violacea has androgenic properties by significantly increasing LH-induced testosterone production in mouse testes with no significant change in cell viability. The third objective of this study was to assess the effect of Sutherlandia frutescens(L.) R.Br and Artemisia afra Jacq. Ex Willd. on the male reproductive system. S. frutescens and A. afra are also plant species indigenous to southern Africa and used locally as a herbal remedy/medicine to treat several ailments. Ethanol extracts of each plant was prepared and cells were treated with varying concentrations of each extract (0, 156.25, 312.5, 625, 1250,2500 and 5000 &mu / g/ml) with or without LH-treatment and incubated for 4 hours. Cytotoxicity by LDH measurement and hormone production (testosterone and estradiol) were endpoints that were evaluated. The results obtained showed that the ethanol extracts of both plants are not cytotoxic to testicular cells and that A. afra decreases testosterone production at high concentrations. The fourth and final objective of this study was to assess the acute effect of four heavy metals, namely manganese, copper, cadmium and magnesium on the male reproductive system. These heavy metals are used extensively in manufacturing and mining industries. Cells were treated with varying concentrations of each metal salt (200, 100, 50, 25, 12.5, and 6.25&nbsp / &mu / M) with or without LH-treatment and incubated for 4 hours. Endpoints evaluated included cell viability, testosterone and estradiol production. The results obtained showed that manganese, cadmium and copper are highly toxic to testicular cells in vitro and therefore may potentially cause reproductive toxicity.</p>
16

Efeito do consumo de hidrolisado de clara de ovo sobre as alterações neurológicas, reprodutivas e cardiovasculares promovidas pela exposição crônica ao cloreto de mercúrio (HgCl2) em ratos

Rizzetti, Danize Aparecida January 2016 (has links)
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