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Parâmetros inflamatórios, imunológicos e histopatológicos da administração prolongada da Ipomoea carnea em ratos: 1. Avaliação em animais adultos 2. Estudo perinatal / Inflammatory, immunological and histopathological parameters of prolonged administration of Ipomoea carnea in rats: 1. Evaluation of adult animals 2. Perinatal studyHueza, Isis Machado 10 November 2006 (has links)
O presente estudo visou avaliar efeitos da I. carnea e de seus princípios ativos sobre a imunidade natural de ratos e, os efeitos de sua administração durante a gestação ou lactação às mães e os possíveis efeitos imunotóxicos sobre os filhotes quando adultos. Nas o resíduo da planta (RAF) foi diluído na água de bebida nas doses-alvo de 3,0 e 15,0g/kg de folhas secas da planta, durante 14 e 21 dias e por via oral, por gavage, na dose de 15,0g/kg, durante 14 dias, para avaliação da atividade de macrófagos (MO) peritoneais e das inflamações crônica e aguda, induzidas pelo BCG e pela carragenina, respectivamente. Os princípios ativos (suainsonina e calisteginas B1, B2, B3 e C1) foram administrados isoladamente em ratas, nas mesmas concentrações presentes em 15,0g/kg do RAF, durante 14 dias, para então avaliar a atividade macrofágica. Em ratas prenhes ou lactantes empregaram-se as doses de 1,0; 3,0; 7,0 e 15,0g/kg do RAF, por gavage. Ainda no estudo perinatal, foram realizados o cross-fostering para observação da passagem transplacentária da suainsonina, a amniocentese e a coleta de leite para quantificação deste alcalóide. As proles foram avaliadas até os 70 dias de vida, para avaliação da atividade macrofágica e das inflamações crônica e aguda. Foram realizados ensaios de imunotoxicidade, (peso relativo de órgãos linfóides, resposta imune humoral e celular), em ratos jovens e adultos, tratados durante 14 dias. No final da experimentação foram coletados diferentes órgãos para o estudo histopatológico. Em relação à imunidade das ratas adultas houve aumento da fagocitose e da produção de peróxido de hidrogênio de MO, maior processo inflamatório crônico e supressão da resposta inflamatória aguda, apenas nas ratas tratadas com baixas doses do RAF. Dos alcalóides da I.carnea, apenas a suainsonina mostrou-se tóxica. Em relação às ninhadas de mães tratadas durante a gestação ou lactação, verificou-se menor peso ao nascimento e menor peso ao desmame, respectivamente. O emprego do cross-fostering evidenciou a passagem da suainsonina pela placenta, confirmada pela quantificação deste alcalóide no líquido amniótico. A suainsonina também foi quantificada no leite. Em relação à imunidade natural da prole de ratas tratadas durante a gestação ou lactação, não se observou alterações nos parâmetros avaliados, porém filhotes de ratas tratadas com a planta durante a lactação e desafiados com o BCG quando adultos, desenvolveram artrite. Nos ensaios imunotóxicos, ratos jovens apresentaram involução tímica, os adultos esplenomegalia e menor celularidade de medula óssea, e em todos os animais, aumento no título de anticorpos. Dos órgãos coletados, apenas o SNC não apresentou as degenerações vacuolares características da toxicose por I.carnea. Concluindo, baixas doses do RAF promovem aumento da atividade de MO. Dos alcalóides da planta, apenas a suainsonina mostrou-se tóxica. A suainsonina passa a barreira placentária, ocasionando ninhadas menores e com menor peso e, também é excretada no leite, ocasionando lesões degenerativas vacuolares, bem como alterações no desenvolvimento tímico, o que possivelmente resultou em autoimunidade quando do desafio imune na idade adulta. Finalmente, em ratos, mesmo em altas doses, não ocorre lesão vacuolar no SNC. / The aim of this study was to evaluate the toxic effect of I. Carnea and its toxins on the immune system of rats, and to evaluate its effects on mothers and offspring when administered to dams during gestation or lactation. An alkaloid-rich plant extract (RAF) was added to drinking water to obtain doses equivalent to 3.0 and 15.0g/kg of dry leaves for 14 and 21 days, and a dose of 15.0 g/kg by gavage for 14 days. Macrophage activity (MO), and chronic and acute inflammation induced by BCG and carragenine, respectively, were evaluated. Each toxin in I. carnea (i.e., swainsonine and calystegines B1, B2, B3 and C1) was administered by gavage to female rats, in similar concentrations as contained in 15.0g/kg of RAF during 14 days to evaluate MO. The RAF was dosed by gavage in pregnant or nursing rats at 1.0, 3.0, 7.0 and 15.0g/kg. Cross-fostering was used to evaluate placental passage of swainsonine; swainsonine concentration was determined in amniotic fluid and in milk. On postpartum day 70 the litters were evaluated for MO and chronic and acute inflammation. Immunotoxic responses were evaluated in young and adult rats treated with RAF for 14 days. Tissue samples were then harvested for histopathology. The immune function of adult rats was enhanced by lower doses of the RAF. Phagocytosis and hydrogen peroxide production were improved, and there was enhancement of chronic immunity, but suppression of acute inflammatory responses. Among the I.carnea alkaloids, only swainsonine showed toxicity. The litters of dams treated with swainsonine during gestation or lactation showed a reduction in body weight at birth and after lactation, respectively. Swainsonine clearly passed through the placenta, and was found in amniotic fluid, and in milk. There were no effects on the immunity of litters from mothers treated during gestation or lactation. However, pups from mothers dosed with swainsonine during lactation had an increased occurrence of arthritis. Further, young rats showed thymus atrophy, whereas adults developed splenomegaly and reduced bone marrow cellularity. Finally, animals of all ages showed enhanced antibody titers. Only CNS tissue did not have the characteristic vacuolar degeneration typical of I. Carnea toxicosis. In conclusion, low doses of RAF enhanced MO activity. Among the I. Carnea alkaloids, only swainsonine showed toxicity. Swainsonine passed the placental barrier, resulting in smaller litters with diminished birth weights. Swainsonine was also excreted in milk, resulting in vacuolar lesions in pups, as well as thymus atrophy, which could cause autoimmunity in adulthood. Finally, even with higher doses, CNS tissue in rats is resistant to the toxic effects of swainsonine.
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Interferência do TSPO sobre as vias de ativação de adipócitos da linhagem 3T3-L1 / Interference of TSPO upon the activation pathways of 3T3-L1 adipocytesBarioni, Éric Diego 02 February 2018 (has links)
A obesidade está associada a um processo inflamatório crônico de baixa intensidade e representa um dos fatores de risco para o desenvolvimento de uma série de comorbidades. A proteína TSPO está envolvida em inúmeras funções celulares, incluindo biossíntese e transporte de esteróides, transporte de porfirinas, apoptose, biossíntese do heme, processos oxidativos e imunomodulação. Ademais, a presença e a função da proteína TSPO no tecido adiposo e na inflamação ainda não estão bem estabelecidas. Deste modo, o objetivo do presente estudo foi validar a expressão e função do TSPO durante a diferenciação de células 3T3-L1, e investigar se o tratamento de adipócitos 3T3-L1 com diazepam, um benzodiazepínico de ação central (GABAA) e periférica (TSPO), é capaz de modular os efeitos inflamatórios induzidos pela incubação das células 3T3-L1 com TNF-α. Nossos resultados evidenciaram que, em nosso estudo, o tratamento de pré-adipócitos com diazepam não modulou a adipogênese. Entretanto, apesar de o diazepam per se não modular o acúmulo de triacilglicerol e a expressão gênica e protéica de PPAR-γ; em células estimuladas pelo TNF-α, o tratamento com diazepam foi capaz de reverter a diminuição da expressão gênica e protéica de PPAR-γ induzida pelo TNF-α. Ademais, o tratamento dos adipócitos com diazepam foi capaz de modular positivamente a expressão protéica de TSPO, efeito este que não observamos em células tratadas pelo clonazepam, um benzodiazepínico de ação exclusivamente central. Em resumo, os dados obtidos neste estudo, pela primeira vez, demonstram a possível relação entre as vias que controlam a sinalização de TSPO, TNF-α e PPAR-γ. Assim, nos é possível inferir que a ativação de TSPO pelo seu ligante diazepam foi capaz de modular a ativação de NF-kB induzida pelo TNF-α, promovendo, com a diminuição da lipólise e aumento da expressão gênica de TSPO e gênica e protéica de PPAR-γ, o reestabelecimento da homeostase celular, o que aumentaria a sobrevida das células, a atividade mitocondrial, e a atividade adipogênica dos adipócitos. / Obesity is associated with a chronic low-grade inflammation and these represents one of the risk factors to development of other non-communicable diseases. TSPO 18 kDa is involved in several cellular functions, including biosynthesis and steroids transport, porphyrin transport, apoptosis, heme biosynthesis, oxidative metabolism and immunomodulation. Furthermore, the TSPO expression and function on adipose tissue and in the chronic low-grade inflammation have not been established. Thus, the aim of present study was to validate the TSPO expression and function on the 3T3-L1 differentiation process and to investigate whether diazepam treatment is able to modulate the TNF-α induced inflammatory effects on 3T3-L1 cells. Our results showed that diazepam treatment of preadipocytes was not able to modulate the adipogenesis. However, although diazepam treatment per se does not modulate the triacylglycerol accumulation and gene and protein expression of PPAR-γ; in TNF-α stimulated adipocytes, the treatment with diazepam was able to modulate the decreased of PPAR-γ gene and protein expression induced by TNF-α. In addition, the diazepam treatment of adipocytes was able to positively modulate the TSPO protein expression, an effect that we did not observe in cells treated with clonazepam, a central benzodiazepine ligand. In summary, the data obtained in this study, for the first time, demonstrate the possible relationship between the pathways that control the TSPO, TNF-α and PPAR-γ signaling. Thus, it is possible that the activation of TSPO by diazepam was able to modulate TNF-α-induced activation of NF-kB, promoting the reduction of lipolysis and increased of TSPO gene expression and PPAR-γ gene and protein expression, reestablishment of cellular homeostasis, which would increase cell survival, mitochondrial activity, and adipogenic activity of adipocytes.
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Parâmetros inflamatórios, imunológicos e histopatológicos da administração prolongada da Ipomoea carnea em ratos: 1. Avaliação em animais adultos 2. Estudo perinatal / Inflammatory, immunological and histopathological parameters of prolonged administration of Ipomoea carnea in rats: 1. Evaluation of adult animals 2. Perinatal studyIsis Machado Hueza 10 November 2006 (has links)
O presente estudo visou avaliar efeitos da I. carnea e de seus princípios ativos sobre a imunidade natural de ratos e, os efeitos de sua administração durante a gestação ou lactação às mães e os possíveis efeitos imunotóxicos sobre os filhotes quando adultos. Nas o resíduo da planta (RAF) foi diluído na água de bebida nas doses-alvo de 3,0 e 15,0g/kg de folhas secas da planta, durante 14 e 21 dias e por via oral, por gavage, na dose de 15,0g/kg, durante 14 dias, para avaliação da atividade de macrófagos (MO) peritoneais e das inflamações crônica e aguda, induzidas pelo BCG e pela carragenina, respectivamente. Os princípios ativos (suainsonina e calisteginas B1, B2, B3 e C1) foram administrados isoladamente em ratas, nas mesmas concentrações presentes em 15,0g/kg do RAF, durante 14 dias, para então avaliar a atividade macrofágica. Em ratas prenhes ou lactantes empregaram-se as doses de 1,0; 3,0; 7,0 e 15,0g/kg do RAF, por gavage. Ainda no estudo perinatal, foram realizados o cross-fostering para observação da passagem transplacentária da suainsonina, a amniocentese e a coleta de leite para quantificação deste alcalóide. As proles foram avaliadas até os 70 dias de vida, para avaliação da atividade macrofágica e das inflamações crônica e aguda. Foram realizados ensaios de imunotoxicidade, (peso relativo de órgãos linfóides, resposta imune humoral e celular), em ratos jovens e adultos, tratados durante 14 dias. No final da experimentação foram coletados diferentes órgãos para o estudo histopatológico. Em relação à imunidade das ratas adultas houve aumento da fagocitose e da produção de peróxido de hidrogênio de MO, maior processo inflamatório crônico e supressão da resposta inflamatória aguda, apenas nas ratas tratadas com baixas doses do RAF. Dos alcalóides da I.carnea, apenas a suainsonina mostrou-se tóxica. Em relação às ninhadas de mães tratadas durante a gestação ou lactação, verificou-se menor peso ao nascimento e menor peso ao desmame, respectivamente. O emprego do cross-fostering evidenciou a passagem da suainsonina pela placenta, confirmada pela quantificação deste alcalóide no líquido amniótico. A suainsonina também foi quantificada no leite. Em relação à imunidade natural da prole de ratas tratadas durante a gestação ou lactação, não se observou alterações nos parâmetros avaliados, porém filhotes de ratas tratadas com a planta durante a lactação e desafiados com o BCG quando adultos, desenvolveram artrite. Nos ensaios imunotóxicos, ratos jovens apresentaram involução tímica, os adultos esplenomegalia e menor celularidade de medula óssea, e em todos os animais, aumento no título de anticorpos. Dos órgãos coletados, apenas o SNC não apresentou as degenerações vacuolares características da toxicose por I.carnea. Concluindo, baixas doses do RAF promovem aumento da atividade de MO. Dos alcalóides da planta, apenas a suainsonina mostrou-se tóxica. A suainsonina passa a barreira placentária, ocasionando ninhadas menores e com menor peso e, também é excretada no leite, ocasionando lesões degenerativas vacuolares, bem como alterações no desenvolvimento tímico, o que possivelmente resultou em autoimunidade quando do desafio imune na idade adulta. Finalmente, em ratos, mesmo em altas doses, não ocorre lesão vacuolar no SNC. / The aim of this study was to evaluate the toxic effect of I. Carnea and its toxins on the immune system of rats, and to evaluate its effects on mothers and offspring when administered to dams during gestation or lactation. An alkaloid-rich plant extract (RAF) was added to drinking water to obtain doses equivalent to 3.0 and 15.0g/kg of dry leaves for 14 and 21 days, and a dose of 15.0 g/kg by gavage for 14 days. Macrophage activity (MO), and chronic and acute inflammation induced by BCG and carragenine, respectively, were evaluated. Each toxin in I. carnea (i.e., swainsonine and calystegines B1, B2, B3 and C1) was administered by gavage to female rats, in similar concentrations as contained in 15.0g/kg of RAF during 14 days to evaluate MO. The RAF was dosed by gavage in pregnant or nursing rats at 1.0, 3.0, 7.0 and 15.0g/kg. Cross-fostering was used to evaluate placental passage of swainsonine; swainsonine concentration was determined in amniotic fluid and in milk. On postpartum day 70 the litters were evaluated for MO and chronic and acute inflammation. Immunotoxic responses were evaluated in young and adult rats treated with RAF for 14 days. Tissue samples were then harvested for histopathology. The immune function of adult rats was enhanced by lower doses of the RAF. Phagocytosis and hydrogen peroxide production were improved, and there was enhancement of chronic immunity, but suppression of acute inflammatory responses. Among the I.carnea alkaloids, only swainsonine showed toxicity. The litters of dams treated with swainsonine during gestation or lactation showed a reduction in body weight at birth and after lactation, respectively. Swainsonine clearly passed through the placenta, and was found in amniotic fluid, and in milk. There were no effects on the immunity of litters from mothers treated during gestation or lactation. However, pups from mothers dosed with swainsonine during lactation had an increased occurrence of arthritis. Further, young rats showed thymus atrophy, whereas adults developed splenomegaly and reduced bone marrow cellularity. Finally, animals of all ages showed enhanced antibody titers. Only CNS tissue did not have the characteristic vacuolar degeneration typical of I. Carnea toxicosis. In conclusion, low doses of RAF enhanced MO activity. Among the I. Carnea alkaloids, only swainsonine showed toxicity. Swainsonine passed the placental barrier, resulting in smaller litters with diminished birth weights. Swainsonine was also excreted in milk, resulting in vacuolar lesions in pups, as well as thymus atrophy, which could cause autoimmunity in adulthood. Finally, even with higher doses, CNS tissue in rats is resistant to the toxic effects of swainsonine.
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Toxicological evaluation of inhalation exposure to benzene and toluene in a raptorial bird, the American kestrel, <i>falco sparverius</i>Olsgard, Mandy Lee 30 August 2007
Benzene and toluene are representative volatile organic compounds (VOCs) released during production, storage, and transportation associated with the oil and gas industry. Benzene and toluene are chemicals of concern because they are released in greater and possibly more biologically significant concentrations than other compounds. <p>Most studies of air pollution in high oil and gas activity areas have neglected to consider risks to top-level predators. Birds can be used as highly sensitive monitors of air quality. Since the avian respiratory tract is physiologically different from a rodent respiratory tract, effects of gases cannot be safely extrapolated from rodent studies. I hypothesized that benzene, being haematotoxic and immunotoxic, along with the neurological and possible endocrine disrupting effects of toluene would be more toxic in birds than in mammals. <p>After two summers of experimental exposure of wild and captive American kestrels to high (10ppm and 80ppm) or environmentally relevant (0.1ppm and 0.8ppm) levels of benzene and toluene, respectively, altered immune, haematopoeitic, behavioural, and endocrine responses characteristic in mammals, were evident in the kestrels.<p>There was a decreased cell mediated immune response as measured by delayed type hypersensitivity tests in all exposed birds (p = 0.028, 0.004). An increase in humoral immunity as compared to control individuals (p = 0.041, 0.031) was also apparent in both dose groups. Plasma retinol levels were decreased in 2005 and 2006 high dose individuals (p = 0.008, 0.048). <p>The majority of haematopoeitic effects involved the erythroid lineage in the bone marrow and the polychromatophilic erythrocytes systemically. There were no significantly adverse responses in the bone marrow with regards to the granuloid lineage but systemically there was a prominent eosinophilia (p = 0.045) and basophilia (p = 0.006) in low exposure groups. The loss of communication between polychromatophilic erythrocytes in the post-mitotic pool within the bone marrow and the peripheral blood was present in low and high exposure individuals compared to control birds (p = 0.013, 0.402, 0.974). The number of polychromatophils in the circulation of low dose group individuals was decreased compared to control birds (p = 0.029). This may be a function of toluenes inability to inhibit biotransformation enzymes at low concentrations leading to blood cell targeting by benzenes increased phenolic metabolite production. This theory is corroborated by the possible decreased benzene metabolism and increased toluene distribution manifesting as increased aggressive responses such as wing beating and vocalization time in the high dose group (p = 0.025, 0.086). <p>The work here has shown American kestrels are sensitive to the air contaminants, benzene and toluene. The present study illustrates the need for reference concentrations for airborne pollutants that are calculated based on data measuring sensitive endpoints specific for avian models. Future studies should evaluate immune, haematopoeitic, and behavioural endpoints, as well as develop more sensitive isoform specific enzyme activity assays to further determine the susceptibility of birds to inhaled toxicants.
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Toxicological evaluation of inhalation exposure to benzene and toluene in a raptorial bird, the American kestrel, <i>falco sparverius</i>Olsgard, Mandy Lee 30 August 2007 (has links)
Benzene and toluene are representative volatile organic compounds (VOCs) released during production, storage, and transportation associated with the oil and gas industry. Benzene and toluene are chemicals of concern because they are released in greater and possibly more biologically significant concentrations than other compounds. <p>Most studies of air pollution in high oil and gas activity areas have neglected to consider risks to top-level predators. Birds can be used as highly sensitive monitors of air quality. Since the avian respiratory tract is physiologically different from a rodent respiratory tract, effects of gases cannot be safely extrapolated from rodent studies. I hypothesized that benzene, being haematotoxic and immunotoxic, along with the neurological and possible endocrine disrupting effects of toluene would be more toxic in birds than in mammals. <p>After two summers of experimental exposure of wild and captive American kestrels to high (10ppm and 80ppm) or environmentally relevant (0.1ppm and 0.8ppm) levels of benzene and toluene, respectively, altered immune, haematopoeitic, behavioural, and endocrine responses characteristic in mammals, were evident in the kestrels.<p>There was a decreased cell mediated immune response as measured by delayed type hypersensitivity tests in all exposed birds (p = 0.028, 0.004). An increase in humoral immunity as compared to control individuals (p = 0.041, 0.031) was also apparent in both dose groups. Plasma retinol levels were decreased in 2005 and 2006 high dose individuals (p = 0.008, 0.048). <p>The majority of haematopoeitic effects involved the erythroid lineage in the bone marrow and the polychromatophilic erythrocytes systemically. There were no significantly adverse responses in the bone marrow with regards to the granuloid lineage but systemically there was a prominent eosinophilia (p = 0.045) and basophilia (p = 0.006) in low exposure groups. The loss of communication between polychromatophilic erythrocytes in the post-mitotic pool within the bone marrow and the peripheral blood was present in low and high exposure individuals compared to control birds (p = 0.013, 0.402, 0.974). The number of polychromatophils in the circulation of low dose group individuals was decreased compared to control birds (p = 0.029). This may be a function of toluenes inability to inhibit biotransformation enzymes at low concentrations leading to blood cell targeting by benzenes increased phenolic metabolite production. This theory is corroborated by the possible decreased benzene metabolism and increased toluene distribution manifesting as increased aggressive responses such as wing beating and vocalization time in the high dose group (p = 0.025, 0.086). <p>The work here has shown American kestrels are sensitive to the air contaminants, benzene and toluene. The present study illustrates the need for reference concentrations for airborne pollutants that are calculated based on data measuring sensitive endpoints specific for avian models. Future studies should evaluate immune, haematopoeitic, and behavioural endpoints, as well as develop more sensitive isoform specific enzyme activity assays to further determine the susceptibility of birds to inhaled toxicants.
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Changes in immune cell populations and the antibody response to Streptococcus pneumoniae after exposure to a mixture of herbicidesDe la Rosa, Patricia. January 2003 (has links)
Thesis (Ph. D.)--West Virginia University, 2003. / Title from document title page. Document formatted into pages; contains xii, 243 p. : ill. Vita. Includes abstract. Includes bibliographical references (p. 213-240).
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Investigation of white blood cell phagocytosis as a potential bio-marker of mercury immunotoxicity in birdsHolloway, Jennifer C. January 2001 (has links)
White blood cell phagocytosis was investigated and used with avian blood, and assessed as a potential biomarker for mercury immunotoxicity in free ranging birds (common loons). Phagocytosis is an essential immunological function and can be measured using flow cytometry. The assay was assessed with in vitro exposure using whole blood and isolated white blood cells (WBC) from domestic chickens, and with in vivo exposure using whole blood from captive doves and wild loons. McHg at 0.1ppm significantly depressed phagocytic capacity of isolated WBCs without affecting their viability, but did not affect phagocytic activity when added to whole blood up to 50ppm. Also, no significant relationship between blood-Hg level and phagocytic capacity of WBCs was observed in ringed turtle doves fed McHg in their diets, nor in wild common loons having a range of blood-Hg concentrations. The phagocytosis assay is a convenient assay for use in field studies of free-living birds, but is not responsive to McHg exposure in birds, and so is not recommended as a biomarker of immunotoxicity in Hg-exposed loons.
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The effects of the herbicide atrazine on mammalian immune functionRowe, Alexander M. January 2007 (has links)
Thesis (Ph. D.)--West Virginia University, 2007. / Title from document title page. Document formatted into pages; contains vi, 183 p. : ill. (some col.). Includes abstract. Includes bibliographical references.
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Interferência do TSPO sobre as vias de ativação de adipócitos da linhagem 3T3-L1 / Interference of TSPO upon the activation pathways of 3T3-L1 adipocytesÉric Diego Barioni 02 February 2018 (has links)
A obesidade está associada a um processo inflamatório crônico de baixa intensidade e representa um dos fatores de risco para o desenvolvimento de uma série de comorbidades. A proteína TSPO está envolvida em inúmeras funções celulares, incluindo biossíntese e transporte de esteróides, transporte de porfirinas, apoptose, biossíntese do heme, processos oxidativos e imunomodulação. Ademais, a presença e a função da proteína TSPO no tecido adiposo e na inflamação ainda não estão bem estabelecidas. Deste modo, o objetivo do presente estudo foi validar a expressão e função do TSPO durante a diferenciação de células 3T3-L1, e investigar se o tratamento de adipócitos 3T3-L1 com diazepam, um benzodiazepínico de ação central (GABAA) e periférica (TSPO), é capaz de modular os efeitos inflamatórios induzidos pela incubação das células 3T3-L1 com TNF-α. Nossos resultados evidenciaram que, em nosso estudo, o tratamento de pré-adipócitos com diazepam não modulou a adipogênese. Entretanto, apesar de o diazepam per se não modular o acúmulo de triacilglicerol e a expressão gênica e protéica de PPAR-γ; em células estimuladas pelo TNF-α, o tratamento com diazepam foi capaz de reverter a diminuição da expressão gênica e protéica de PPAR-γ induzida pelo TNF-α. Ademais, o tratamento dos adipócitos com diazepam foi capaz de modular positivamente a expressão protéica de TSPO, efeito este que não observamos em células tratadas pelo clonazepam, um benzodiazepínico de ação exclusivamente central. Em resumo, os dados obtidos neste estudo, pela primeira vez, demonstram a possível relação entre as vias que controlam a sinalização de TSPO, TNF-α e PPAR-γ. Assim, nos é possível inferir que a ativação de TSPO pelo seu ligante diazepam foi capaz de modular a ativação de NF-kB induzida pelo TNF-α, promovendo, com a diminuição da lipólise e aumento da expressão gênica de TSPO e gênica e protéica de PPAR-γ, o reestabelecimento da homeostase celular, o que aumentaria a sobrevida das células, a atividade mitocondrial, e a atividade adipogênica dos adipócitos. / Obesity is associated with a chronic low-grade inflammation and these represents one of the risk factors to development of other non-communicable diseases. TSPO 18 kDa is involved in several cellular functions, including biosynthesis and steroids transport, porphyrin transport, apoptosis, heme biosynthesis, oxidative metabolism and immunomodulation. Furthermore, the TSPO expression and function on adipose tissue and in the chronic low-grade inflammation have not been established. Thus, the aim of present study was to validate the TSPO expression and function on the 3T3-L1 differentiation process and to investigate whether diazepam treatment is able to modulate the TNF-α induced inflammatory effects on 3T3-L1 cells. Our results showed that diazepam treatment of preadipocytes was not able to modulate the adipogenesis. However, although diazepam treatment per se does not modulate the triacylglycerol accumulation and gene and protein expression of PPAR-γ; in TNF-α stimulated adipocytes, the treatment with diazepam was able to modulate the decreased of PPAR-γ gene and protein expression induced by TNF-α. In addition, the diazepam treatment of adipocytes was able to positively modulate the TSPO protein expression, an effect that we did not observe in cells treated with clonazepam, a central benzodiazepine ligand. In summary, the data obtained in this study, for the first time, demonstrate the possible relationship between the pathways that control the TSPO, TNF-α and PPAR-γ signaling. Thus, it is possible that the activation of TSPO by diazepam was able to modulate TNF-α-induced activation of NF-kB, promoting the reduction of lipolysis and increased of TSPO gene expression and PPAR-γ gene and protein expression, reestablishment of cellular homeostasis, which would increase cell survival, mitochondrial activity, and adipogenic activity of adipocytes.
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Investigation of white blood cell phagocytosis as a potential bio-marker of mercury immunotoxicity in birdsHolloway, Jennifer C. January 2001 (has links)
No description available.
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