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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.
111

Função pulmonar, estresse oxidativo e marcadores inflamatórios na lesão pulmonar aguda induzida por lipopolissacarídeo: diferentes efeitos da atorvastatina, pravastatina e simvastatina / Redox markers and inflammation are affected differently by atorvastatin, pravastatin or simvastatin administered before endotoxin induced extrapulmonary acute lung injury

Adriana Corrêa Melo 15 August 2012 (has links)
Nosso objetivo foi determinar que tipo de estatina pode atenuar a lesão pulmonar aguda (LPA) induzida por lipopolissacarídeo (LPS) em camundongos da linhagem C57Bl/6. Trinta camundongos machos ( 23 g) foram divididos em 5 grupos (n=6 cada): grupo LPS (10 mg/kg) administrado intraperitonealmente (i.p.), LPS mais atorvastatina (10 mg/kg/dia; grupo LPS+A), LPS mais pravastatina (5 mg/kg/dia; grupo LPS+P) e LPS mais sinvastatina (20 mg/kg/dia; grupo LPS+S). O grupo controle recebeu salina i.p.. Em um grupo separado de camundongos (n=5), a soma das pressões pulmonares resistivas e viscoelásticas (DeltaPtot) e elastância estática (E[st]) foram medidas. Um dia após a administração de LPS os camundongos foram sacrificados (24 h) por deslocamento cervical e logo em seguida foi realizado lavado broncoalveolar (LBA). Os pulmões foram removidos para análise histopatológica e homogeneizados para análises bioquímicas (ELISA, catalase, superóxido dismutase, mieloperoxidase, substâncias reativas ao ácido tiobarbitúrico, carbonilação de proteínas e método de Griess). A quantidade de leucócitos foi menor no grupo LPS+P (p<0,01) e LPS+S (p<0,05) em comparação ao grupo LPS. Os níveis de MCP-1 e IL-6 reduziram no grupo LPS+P (p<0,01), enquanto o grupo LPS + S mostrou redução apenas nos níveis de IL-6 (p<0,05) em comparação ao grupo LPS. Marcadores redox (superóxido dismutase e catalase) foram menores no grupo LPS+A (p<0,01) em comparação ao grupo LPS. A peroxidação lipídica (malondialdeído e hidroperóxidos) diminuiu em todos os grupos tratados (p<0,05) quando comparados ao grupo LPS. A mieloperoxidase foi menor no grupo LPS+P (p<0,01) quando comparado ao grupo LPS. DeltaPtot e E(st) foram, significativamente, maiores no grupo LPS do que nos outros grupos. Nossos resultados sugerem que atorvastatina e pravastatina, mas não a sinvastatina, exibiram ações anti-inflamatórias e antioxidantes na LPA induzida por LPS. / To determinate what statins could attenuate acute lung injury (ALI) induced by lipopolysaccharide (LPS) in C57BL/6 mice. Young male mice ( 23 g) were divided into 5 groups (n=6 each): injected with LPS i.p. (10 mg/kg), LPS plus atorvastatin (10 mg/kg/day; LPS+A group) or pravastatin (5 mg/kg/day; LPS+P group) or simvastatin (20 mg/kg/day; LPS+S group). Control group received saline (i.p.). In a separated group of mice (n=5) the sum of pulmonary resistive and viscoelastic pressures (DeltaPtot) and static elastance (E[st]) were measured. One day later (24 h), the animals were sacrificed, BAL performed and lungs were removed for histopathological analysis and homogenized for biochemical analyses (ELISA, catalase, superoxide dismutase, myeloperoxidase, thiobarbituric acid reactive substances, protein carbonyls and griess assay). The amount of leukocytes was lower in LPS+P (p<0.01) and LPS+S (p<0.05). Cytokine levels of MCP-1 was lower in LPS+P (p<0.01) while IL-6 was lower in LPS+P (p<0.01) and LPS+S (p <0.05). Redox markers (superoxide dismutase and catalase) were lower in LPS+A (p<0.01). Lipid peroxidation (malondialdehyde and hydroperoxides) were lower in all treated groups (p<0.05). Myeloperoxidase was lower in LPS+P (p<0.01). DeltaPtot and E(st) were significantly higher in the LPS group than in the other groups. Our results suggest that atorvastatin and pravastatin, but no simvastatin, exhibits anti-inflammatory and antioxidant actions in LPS-induced ALI.
112

Avaliação da produção de estatinas e compostos antimicrobianos por fungos isolados de cana de açúcar em cultivo semi-sólido. / Production of statins and antimicrobial compounds in solid state fermentation by fungi isolated from sugar cane plants.

Felipe Andres Monsalve Marin 16 October 2015 (has links)
As estatinas são os agentes mais eficazes para a redução de colesterol no tratamento de doenças cardiovasculares, e algumas destas moléculas podem ser produzidas através de processos biológicos como o cultivo semi-sólido de fungos filamentosos. O objetivo deste estudo foi determinar a capacidade de produção de estatinas e compostos antimicrobianos por cinco cepas de fungos isolados de Cana de Açúcar. Para isso, extratos obtidos a partir dos cultivos foram analisados por métodos analíticos como CLAE e RMN para determinar a presença de estatinas; adicionalmente, os extratos foram testados contra diferentes modelos biológicos incluindo bactérias, leveduras, fungos filamentosos, células de ovário de hamster chinês, e parasitas. De acordo com os resultados obtidos, os cinco fungos avaliados não produzem estatinas, e em relação ao biomonitoramento dos extratos foi observado um efeito biológico sobre os parasitas e as células de mamífero, no entanto, é possível que o efeito obtido seja uma resposta dos compostos do substrato dos cultivos (Farelo de trigo). / Statins are the most effective cholesterol lowering agents for the treatment of cardiovascular disease, and some of these molecules can be produced through biological process such as the solid state fermentation. The aim of this study was determinate the capability of production of statins and antimicrobials compounds by five strains of fungi isolated from Brazilian sugar cane. For this purpose, extracts were obtained from the cultures and analyzed through analytical methods as HPLC and NMR in order to determinate the presence of statins; in addition, the extracts were tested against different biological models including bacteria, yeast, filamentous fungi, chinese hamster ovary cells, and parasites. According to the results obtained, the five fungal strains tested did not produce statins, and the extracts produced a biological effect against the parasites and mammalian cells, nevertheless it is possible that this effect observed was a response of the compounds from the culture substrate (wheat bran).
113

Analysis of risk factors in patients with severe chronic kidney disease. The role of atorvastatin.

Holmberg, Benny January 2013 (has links)
Background and aim: There had been no randomized end-point studies with statins for patients with severe renal failure. The purpose of this prospective, open, randomized, controlled study was to investigate whether atorvastatin (10 mg/day) would alter cardiovascular end-points and the overall mortality rate of patients with chronic kidney disease stage 4 or 5 (creatinine clearance&lt;/30 ml/min) and to influence risk factors. Material &amp; Methods: This was an open, prospective, randomized study. A total of 143 patients were included: 73 were controls and 70 were prescribed 10 mg/day of atorvastatin. As efficacy variables, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol and triglyceride levels were determined at the start of the study and at 1, 3, 6, 12, 18, 24, 30 and 36 months. The primary end-points were all cause of mortality, non-lethal acute myocardial infarction, and coronary artery intervention. Various risk factors were studied. In the 97 patients on haemodialysis inter dialysis weight gain (IDWG) was calculated as ultrafiltration in kg/body weight in kg given in percentage of the weight. The burden of IDWG was analyzed. Results: In the atorvastatin group, total cholesterol and low-density lipoprotein cholesterol were significantly reduced, the latter by 35% at 1 month and then sustained. Atorvastatin was withdrawn in 23% of patients due to unacceptable side effects, most frequent complaints being gastrointestinal discomfort and headache. Primary end-points occurred in 74% of the subjects. There was no difference in cardiovascular endpoint and survival between the control and atorvastatin groups. The 5-year end-point-free survival rate from study entry was 20%. There was no evidence of more benefit of atorvastatin for patients with diabetes mellitus and chronic kidney disease versus the other patients; instead plasma fibrinogen increased. The IDWG was significantly larger in patients who suffered from end-points due to cardiovascular reasons, cardiac reasons, congestive heart failure, aortic aneurysm, and intracerebral bleeding. Conclusion: These data showed that in contrast to other patient groups, patients with severe chronic kidney disease 4 and 5, including those with diabetes mellitus, seem to have no benefit from 10mg/day of atorvastatin. Instead we found a high IDWG to be an important risk factor that should be prevented. There was no evident connection between atorvastatin medication and IDWG.
114

Effects of peri-operative statin treatment on atrial electrical properties, post-operative atrial fibrillation and in-hospital clinical outcomes in patients undergoing elective cardiac surgery

Jayaram, Raja January 2014 (has links)
Surgical myocardial revascularization remains the standard of care for patients with multi-vessel coronary artery disease. A growing body of evidence indicates that systemic inflammation and myocardial oxidative stress are associated with the development of postoperative atrial fibrillation (POAF) and low cardiac output syndrome in patients undergoing cardiac surgery. Statins have been shown to exert rapid anti-inflammatory and antioxidant effects by inhibiting myocardial NOX2 oxidases and by increasing the bioavailability of nitric oxide (NO). However, whether these so-called pleiotropic effects of statins result in improved patient outcomes remains to be established. To provide further insights into the mechanisms of action and impact on clinical outcomes of peri-operative statin treatment in patients undergoing cardiac surgery, I studied the molecular mechanisms underlying the myocardial nitroso-redox balance in samples of the right atrial appendages (RAA) obtained before (PRE) and after cardiopulmonary bypass (CPB) and reperfusion (POST) and setup two double-blind randomised placebo-controlled trials: 1) STARR (Statin Treatment on Atrial Refractoriness and Reperfusion injury), which tested the effect of Atorvastatin (80 mg once daily for up to 6 days before surgery and 5 days after) on the atrial effective refractory period (AERP, over 4 post-operative days) and superoxide production in paired PRE- and POST- RAA samples from 60 patients 2) STICS (Statin Treatment In Cardiac Surgery), which assessed the effects of peri-operative treatment with Rosuvastatin (20mg od) on POAF (assessed by continuous holter ECG monitoring for 5 days postoperatively) and myocardial injury (assessed by serial troponin I measurements) in 1922 patients undergoing elective cardiac surgery. I observed that atrial superoxide production increased significantly after reperfusion due to increased mitochondrial and NOX2 oxidase activity and to uncoupling of NOS activity. NOS activity in RAA samples decreased significantly after reperfusion (by 60&percnt;), but this reduction was not prevented by BH4 supplementation (10 &mu;M) or NOX2 inhibition. Instead, I identified increased endothelial NOS S-glutathionylation as the main mechanism responsible for NOS uncoupling after reperfusion. In STARR, atorvastatin prevented increase in RAA superoxide production, maintained the functionally coupled status of NOS and NO bioavailability after reperfusion but had no measurable effect on postoperative AERP. In STICS, treatment with rosuvastatin significantly reduced LDL-C concentration by 48 hours after surgery but had no effect on the incidence of POAF (203 (21&percnt;) of the Rosuvastatinallocated patients vs. 197 (20&percnt;) of the placebo-allocated patients) or on perioperative myocardial damage (P = 0.80). Pre-defined subgroup analyses (age, sex, prior statin use, baseline troponin concentration, duration of randomized treatment before surgery, type of cardiac surgery, and postoperative use of anti-inflammatory drugs) did not identify any category of patient who benefited from perioperative rosuvastatin treatment. Nor were there beneficial effects on any of the other in-hospital clinical outcomes that were assessed. In conclusion, cardiac surgery on CPB is associated with myocardial nitroso redox imbalance that is reversed by perioperative intensive therapy with statins. However, these effects have no beneficial effects on common in-hospital complications after elective cardiac surgery. Although the benefits of long-term statin therapy in patients requiring myocardial revascularization are well established, the work presented in this thesis does not support routine use of perioperative intensive therapy with statins for the prevention of postoperative complications in patients undergoing elective cardiac surgery.
115

Avaliação dos Produtos de Degradação em Comprimidos de Sinvastatina: Estudos de Estabilidade e Validação de Métodos / Degradation Products Assessment Simvastatin Tablets: Stability Studies and Methods Validation

Fonseca, Erika Bachini January 2012 (has links)
Made available in DSpace on 2016-07-01T11:59:27Z (GMT). No. of bitstreams: 2 license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) 2.pdf: 2625869 bytes, checksum: 8cb28dd9acaae218862e11d5bbeec859 (MD5) Previous issue date: 2012 / Made available in DSpace on 2016-07-21T14:39:31Z (GMT). No. of bitstreams: 2 2.pdf: 2625869 bytes, checksum: 8cb28dd9acaae218862e11d5bbeec859 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2012 / Fundação Oswaldo Cruz. Instituto de Tecnologia em Fármacos/Farmanguinhos. Rio de Janeiro, RJ, Brasil. / As estatinas são substâncias que reduzem os níveis lipídicos no sangue, sendo a hipercolesterolemia o fator causal da aterosclerose, doenças coronarianas dentre outras. Devido ao alto índice do distúrbio na população brasileira, as estatinas são usadas como tratamento de primeira escolha, por serem mais seguras e eficazes. Sendo que duas estatinas (a atorvastatina e a sinvastatina) fazem parte da RENAME e sinvastatina incluída no programa Aqui tem farmácia popular . Devido à ampla utilização da sinvastatina, faz-se necessária a avaliação da qualidade dos medicamentos, sendo relevante o conhecimento de sua estabilidade química e física até o fim de seu prazo de validade. O monitoramento de produtos de degradação faz parte desta avaliação e é necessária a implementação de metodologias analíticas validadas de pesquisa destas impurezas na rotina dos estudos de estabilidade. Além disso, é essencial o desenvolvimento contínuo de formulações melhoradas para garantir a disponibilidade, eficácia e segurança do fármaco. A maioria das técnicas descritas na literatura são usadas para quantificar o teor de sinvastatina e seus metabólitos no sangue. Os compêndios oficiais disponibilizam apenas metodologia para a quantificação de produtos de degradação na matéria-prima. O objetivo deste trabalho foi avaliar a formação de produtos de degradação na formulação de comprimidos durante o prazo de validade. Para isto, foram propostas a adaptação e a validação da metodologia da Farmacopéia Americana da matéria-prima. O método proposto empregou coluna cromatográfica C18 e fase móvel constituída de de solução de ácido fosfórico e acetonitrila misturados por gradiente de eluição com tempo total de corrida de 13 minutos. O fluxo empregado foi de 3 mL/min. e detecção UV/VIS a 238 nm. A metodologia apresentou resultados satisfatórios de especificidade, linearidade, precisão, exatidão e robustez. O estudo de estabilidade foi conduzido numa condição controlada de temperatura e umidade (30ºC, 75% U.R.) ao longo do prazo de validade e demonstrou que não há formação ou aumento dos níveis dos produtos de degradação na formulação de comprimidos. / Statins are substances that reduce blood lipid levels, being hypercholesterolemia the causative factor of atherosclerosis, coronary heart disease among others. Due to the high rate of the disorder in the population, statins are used as first-line treatment because of are their safety and effectiveness. Two statins (atorvastatin and simvastatin) are part of RENAME and simvastatin is included in the program "Here's pharmacy popular".Due to the wide use of simvastatin, it is necessary to evaluate the quality of drugs being relevant knowledge of their chemical and physical stability until the end of its shelf life. The monitoring of degradation products and is part of this assessment an it is necessary to implement validated analytical methodologies in the routine of stability studies. Furthermore, it is essential to continuing development of improved formulations for the availability, effectiveness and safety of the drug.Most techniques described in literature are used to quantify the amount of simvastatin and its metabolites in blood. The official compendia only provide methodology for quantification of degradation products in raw material.The aim of this study was to evaluate the formation of degradation products in tablet formulation during the shelf life. For this, was proposed adaptation and validation of the methodology of the American Pharmacopoeia of the raw material. The proposed method employed C18 chromatographic column and a mobile phase consisting of a phosphoric acid solution and acetonitrile mixed by gradient elution with a total run time of 13 minutes. The flow was 3 ml / min. and detection UV / VIS at 238 nm. The methodology presented satisfactory specificity, linearity, precision, accuracy and robustness. The stability study was conducted in a controlled condition of temperature and humidity (30 ° C, 75% RH) during the shelf life and showed no training or increased levels of degradation products in tablet formulation.
116

RETIRADA DO TRATAMENTO COM ATORVASTATINA E O DANO POR ESPÉCIES REATIVAS NO CÓRTEX CEREBRAL DE RATOS / ATORVASTATIN TREATMENT WITHDRAWAL AND THE DAMAGE BY REACTIVE SPECIES IN RATS CEREBRAL CORTEX

Oliveira, Clarissa Vasconcelos de 27 February 2013 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Statins are drugs used in dislipidemias treatment. These agents are reversible inhibitors of the rate-limiting enzyme in cholesterol biosynthesis,the 3-hydroxy-3-methylglutaryl-coenzyme A reductase, and preventing de conversion of HMG-CoA to mevalonate. Besides reducing the plasma cholesterol, statins also present effects which seem cholesterol-independent, the so-called pleiotropic effects of statins. Date in literature has been shown that HMG-CoA inhibitors display neuroprotective properties, mainly related to improvement in vascular function due to increase in nitric oxide production, in this context, this class of drugs has proven usefull in treatment and prevention of neurodegenerative disorders such as Alzheimer´s and Parkinson´s. On the other hand, studies based on clinical data have shown that after abrupt discontinuation of statin therapy occurs a period in which the protective properties are lost, and deleterious effects are activated, leading to the appearance of rebound deterioration of vasculature which seems to be associated with alterations in enzymes activities endhotelial nitric oxide synthase and NADPH oxidase. However, little is known about whether these effects of statin withdrawal syndrome in the central nervous system. Therefore, this study aimed to investigate the effect of atorvastatin treatment withdrawal in the rat cerebral cortex. For this purpose, different parameters of oxidative/nitrosative stress were measured, including nitric oxide levels, the immunoreactivity for damage markers 3-nitrotyrosine, 4-hydroxynonenal and carbonyl, the activity of pro-oxidant enzymes NADPH oxidase and xanthine oxidase and the activity of antioxidant enzymes mitochondrial and citoplasmatic superoxide dismutase, catalase and glutathione-S-transferase. The results indicate that atorvastatin withdrawal decreases mitochondrial superoxide dismutase activity and increases NADPH oxidase activity, which may increase superoxide radical levels. Associated with this was seen a decreased in the level of nitric oxide ans increased in 3-nitrotyrosine immunoreactivity, suggesting that superoxide is reacting with nitric oxide leading the formation of peroxinitrite, which leads to proteins nitration. Increasing in the 3-NT/MnSOD ratio, and enzyme expression seen by western blot confirms the assumption that MnSOD is being nitrated, that nitration leads to lower superoxide detoxification. In conclusion, withdrawal of atorvastatin treatment occasioned oxidative/nitrosative damage in the rat cerebral cortex due to alterations in pro-oxidant and antioxidant enzymes activities. / As estatinas são fármacos utilizados no tratamento das dislipidemias. Esses agentes são inibidores reversíveis da enzima limitante da via de biossíntese do colesterol, a 3-hidróxi-3-metilglutaril-coenzima A redutase, e impedem a conversão do HMG-CoA a mevalonato. Além da capacidade de diminuir o colesterol plasmático, as estatinas também possuem efeitos que são independentes da inibição da via de biossíntese do colesterol, são os chamados efeitos pleiotrópicos. Dados da literatura tem demonstrado que os inibidores da HMG-CoA redutase possuem propriedades neuroprotetoras, relacionadas à melhora na função vascular devido ao aumento da produção de óxido nítrico, neste contexto, essa classe de fármacos tem se mostrado útil no tratamento e na prevenção de doenças neurodegenerativas tais como, Alzheimer e Parkinson. Por outro lado, estudos baseados em dados clínicos mostram que a após a interrupção abrupta do tratamento com estatinas ocorre um período em que as propriedades protetoras geradas são perdidas, e efeitos deletérios são ativados, levando ao aparecimento de uma deterioração rebote na vasculatura, o qual parece estar associado a alterações na atividade das enzimas óxido nítrico sintase endotelial e NADPH oxidase. Contudo, até o momento, pouco se sabe sobre esse feito da síndrome da retirada da estatina no sistema nervoso central. Sendo assim, esse estudo teve por objetivo verificar o efeito da retirada do tratamento com atorvastatina no córtex cerebral de ratos. Para isso, diferentes parâmetros do estresse oxidativo/nitrosativo foram medidos, tais como a imunoreatividade para os marcadores de dano 3-nitrotirosina, 4-hidroxinonenal e carbonil, a atividade das enzimas pró-oxidantes NADPH oxidase e xantina oxidase e das enzimas antioxidantes superóxido dismutase mitocondrial e citoplasmática, catalase e glutationa-S-transferase, bem como, o nível de óxido nítrico medido através do nitrito e nitrato. Os resultados obtidos mostram que a retirada do tratamento provoca diminuição na atividade da superóxido dismutase mitocondrial aumento na atividade da NADPH oxidase, o que sugere estar ocorrendo aumento na quantidade de radical superóxido. Associado a isso, foi visto diminuição no nível de óxido nítrico e aumento na imunoreatividade para 3-nitrotirosina, o que sugere que o superóxido está reagindo com o óxido nítrico levando a formação de peroxinitrito. Este último provoca a nitração de proteínas. O aumento da razão 3-NT/MnSOD, e da expressão da enzima visto por western blot, comprova a suposição de que a superóxido dismutase mitocondrial está sendo nitrada, essa nitração leva a uma menor detoxificação do superóxido, de modo que assim, é formado um ciclo. Assim, conclui-se que a retirada do tratamento com atorvastatina provoca dano oxidativo/nitrosativo no córtex cerebral de ratos devido a alterações na atividade das enzimas pró e anti-oxidantes.
117

Função pulmonar, estresse oxidativo e marcadores inflamatórios na lesão pulmonar aguda induzida por lipopolissacarídeo: diferentes efeitos da atorvastatina, pravastatina e simvastatina / Redox markers and inflammation are affected differently by atorvastatin, pravastatin or simvastatin administered before endotoxin induced extrapulmonary acute lung injury

Adriana Corrêa Melo 15 August 2012 (has links)
Nosso objetivo foi determinar que tipo de estatina pode atenuar a lesão pulmonar aguda (LPA) induzida por lipopolissacarídeo (LPS) em camundongos da linhagem C57Bl/6. Trinta camundongos machos ( 23 g) foram divididos em 5 grupos (n=6 cada): grupo LPS (10 mg/kg) administrado intraperitonealmente (i.p.), LPS mais atorvastatina (10 mg/kg/dia; grupo LPS+A), LPS mais pravastatina (5 mg/kg/dia; grupo LPS+P) e LPS mais sinvastatina (20 mg/kg/dia; grupo LPS+S). O grupo controle recebeu salina i.p.. Em um grupo separado de camundongos (n=5), a soma das pressões pulmonares resistivas e viscoelásticas (DeltaPtot) e elastância estática (E[st]) foram medidas. Um dia após a administração de LPS os camundongos foram sacrificados (24 h) por deslocamento cervical e logo em seguida foi realizado lavado broncoalveolar (LBA). Os pulmões foram removidos para análise histopatológica e homogeneizados para análises bioquímicas (ELISA, catalase, superóxido dismutase, mieloperoxidase, substâncias reativas ao ácido tiobarbitúrico, carbonilação de proteínas e método de Griess). A quantidade de leucócitos foi menor no grupo LPS+P (p<0,01) e LPS+S (p<0,05) em comparação ao grupo LPS. Os níveis de MCP-1 e IL-6 reduziram no grupo LPS+P (p<0,01), enquanto o grupo LPS + S mostrou redução apenas nos níveis de IL-6 (p<0,05) em comparação ao grupo LPS. Marcadores redox (superóxido dismutase e catalase) foram menores no grupo LPS+A (p<0,01) em comparação ao grupo LPS. A peroxidação lipídica (malondialdeído e hidroperóxidos) diminuiu em todos os grupos tratados (p<0,05) quando comparados ao grupo LPS. A mieloperoxidase foi menor no grupo LPS+P (p<0,01) quando comparado ao grupo LPS. DeltaPtot e E(st) foram, significativamente, maiores no grupo LPS do que nos outros grupos. Nossos resultados sugerem que atorvastatina e pravastatina, mas não a sinvastatina, exibiram ações anti-inflamatórias e antioxidantes na LPA induzida por LPS. / To determinate what statins could attenuate acute lung injury (ALI) induced by lipopolysaccharide (LPS) in C57BL/6 mice. Young male mice ( 23 g) were divided into 5 groups (n=6 each): injected with LPS i.p. (10 mg/kg), LPS plus atorvastatin (10 mg/kg/day; LPS+A group) or pravastatin (5 mg/kg/day; LPS+P group) or simvastatin (20 mg/kg/day; LPS+S group). Control group received saline (i.p.). In a separated group of mice (n=5) the sum of pulmonary resistive and viscoelastic pressures (DeltaPtot) and static elastance (E[st]) were measured. One day later (24 h), the animals were sacrificed, BAL performed and lungs were removed for histopathological analysis and homogenized for biochemical analyses (ELISA, catalase, superoxide dismutase, myeloperoxidase, thiobarbituric acid reactive substances, protein carbonyls and griess assay). The amount of leukocytes was lower in LPS+P (p<0.01) and LPS+S (p<0.05). Cytokine levels of MCP-1 was lower in LPS+P (p<0.01) while IL-6 was lower in LPS+P (p<0.01) and LPS+S (p <0.05). Redox markers (superoxide dismutase and catalase) were lower in LPS+A (p<0.01). Lipid peroxidation (malondialdehyde and hydroperoxides) were lower in all treated groups (p<0.05). Myeloperoxidase was lower in LPS+P (p<0.01). DeltaPtot and E(st) were significantly higher in the LPS group than in the other groups. Our results suggest that atorvastatin and pravastatin, but no simvastatin, exhibits anti-inflammatory and antioxidant actions in LPS-induced ALI.
118

Význam biosyntetické a katabolické dráhy cholesterolu u nádorových a zánětlivých onemocnění / The importance of biosynthetic and catabolic pathway of cholesterol in inflammatory and tumor diseases

Leníček, Martin January 2011 (has links)
This thesis focuses on the importance of intermediate products of biosynthetic and catabolic pathway of cholesterol. The aim of the first part of the thesis is mainly to investigate, whether statins (HMG- CoA reductase inhibitors) possess antitumor properties and to compare the differences in antitumor potential of individual statins. The other part of the thesis aims at the utilization of 7α-hydroxycholest-4-en-3-one (C4), a promising marker of cholesterol 7α-monooxygenase (CYP7A1) activity and bile acid malabsorption. We demonstrated antitumor effect of statins on an experimental model of pancreatic cancer. Individual statins, however, differed significantly in their efficacy, depending on their physico-chemical properties. Our data suggests, that the most likely (but not the only) mechanism of antitumor effect of statins is decreased prenylation of signaling proteins, especially Ras protooncogene. We set up a reliable method for measurement of C4, which facilitated our research in CYP7A1 regulation. We demonstrated, that promoter polymorphism -203A>C might affect CYP7A1 activity, that diurnal variability of CYP7A1 activity might be triggered by insulin, and that insulin resistance in patients with non-alcoholic fatty liver disease impedes the feedback regulation of CYP7A1, which may lead to disease...
119

Efeitos de hipolipemiantes e polimorfismos sobre a expressão dos genes HMGCR, LDLR, SREBF1a, SREBF2, SCAP e NPC1L1 em indivíduos hipercolesterolêmicos. / Lipid lowering and polymorphisms effects on the expression of HMGCR, LDLR, SREBF1a, SREBF2, SCAP and NPC1L1 genes in hypercholesterolemic subjects.

Simone Sorkin Arazi 09 December 2008 (has links)
A homeostase do colesterol é mediada por proteínas envolvidas na absorção (NPC1L1), regulação (SREBP1, SREBP2, SCAP), síntese (HMGCR) e remoção plasmática (LDLR). Os fármacos inibidores da síntese (vastatinas) e absorção (ezetimiba) do colesterol são potentes agentes hipocolesterolemiantes. Alterações em vários genes têm sido associadas a diferenças na resposta a diversos agentes terapêuticos. Com a finalidade de estudar os efeitos de hipolipemiantes e polimorfismos sobre a expressão dos genes HMGCR, LDLR, SREBF1a, SREBF2, SCAP e NPC1L1, foram selecionados 25 indivíduos com hipercolesterolemia familial (HF), 72 com hipercolesterolemia não familial (HNF) e 125 indivíduos normolipidêmicos e sem doença cardiovascular (NL). Os indivíduos HF foram tratados com sinvastatina (40 mg/dia/4 sem) combinada ou não com ezetimiba (10 mg/dia/4sem) e os HNF foram tratados com atorvastatina (10 mg/dia/4sem). Amostras de sangue foram obtidas antes e após o tratamento para a extração de DNA e RNA e analise do perfil lipídico sérico. A expressão de mRNA dos genes SREBF1a, SREBF2, SCAP, HMGCR, LDLR e NPC1L1 em células mononucleares do sangue periférico (CMSP) foi determinada por RT-PCR em tempo real empregando-se o gene da GAPD como controle endógeno. Os polimorfismos SREBF1a 36delG, SREBF2 G1784C e SCAP A2386G foram determinados por PCR-RFLP. Os indivíduos HF apresentaram maior expressão de mRNA dos genes NPC1L1, HMGCR e LDLR que os grupos HNF e NL (p<0,05). O efeito da atorvastatina sobre a expressão dos genes estudados parece depender da expressão basal nos indivíduos HNF. A variação da expressão após o tratamento com atorvastatina nos pacientes do grupo HNF esteve correlacionada nos genes: SREBF1a e SREBF2; SREBF1a e SCAP; SREBF1a e LDLR; SREBF2 e SCAP; SREBF2 e LDLR; HMGCR e LDLR. O tratamento com sinvastatina e ezetimiba não modificou o padrão de expressão dos genes estudados no grupo HF. Os polimorfismos SREBF2 G1784C e SCAP A2386G parecem estar relacionados com diminuição da expressão de mRNA após o tratamento com atorvastatina. Foi observado que os portadores do genótipo GG do polimorfismo SREBF2 G1784C apresentaram maiores concentrações séricas de colesterol total e LDL-C após o tratamento com atorvastatina. O polimorfismo SCAP A2386G parece estar associado com maiores concentrações de apoB em pacientes do grupo HNF antes do tratamento com atorvastatina. Os resultados são sugestivos que os genes HMGCR, LDLR e NPC1L1 são regulados diferentemente de acordo com o estado metabólico do indivíduo e a taxa de expressão de mRNA é influenciada pelos polimorfismos SREBF2 G1784C e SCAP A2386G após o tratamento com atorvastatina / The regulation of cholesterol is mediated by proteins involved in the absorption (NPC1L1), regulation (SREBP1, SREBP2, SCAP), synthesis (HMGCR) and removal of plasma cholesterol (LDLR). Potent hypocholesterolemic agents inhibit cholesterol synthesis (statins) and its absortion (ezetimibe). Changes in several genes have been associated to different responses to various therapeutic agents. In order to evaluate the association between genes involved in the metabolism of cholesterol and their response to lipid lowering drugs, patients with familial (FH, n = 25) and non familial hypercholesterolemia (NHF, n = 72) were selected. Additionally, 125 normolipidemic individuals and without cardiovascular disease were selected (NL). The HF group were treated with simvastatin (40 mg/day/4 weeks) combined or not with ezetimibe (10 mg/day/4weeks). The NHF group were treated with atorvastatin (10 mg/day/4weeks). Blood samples were obtained prior to and following treatment for extraction of DNA and RNA, and serum lipid profile analysis. The mRNA expression of SREBF1a, SREBF2, SCAP, HMGCR, LDLR, and NPC1L1 genes was determined by real time RT-PCR using the GAPD gene as endogenous control. The polymorphisms SREBF1a-36delG, SREBF2 G1784C, and SCAP A2386G were determined by PCR-RFLP. Individuals with HF showed higher expression of mRNA of genes NPC1L1, HMGCR and LDLR when compared with HNF and NL groups (p <0.05). The effect of atorvastatin on the gene expression seems to depend on the baseline expression in HNF subjects. The change of expression after treatment with atorvastatin in group HNF was correlated as followed: SREBF1a and SREBF2; SREBF1a and SCAP; SREBF1a and LDLR; SREBF2 and SCAP; SREBF2 and LDLR; HMGCR and LDLR. Treatment with simvastatin and ezetimibe did not change the gene-expression profile in HF group. The polymorphisms SREBF2 G1784C, and SCAP A2386G appear to be related to a decreased expression of mRNA after treatment with atorvastatin. HNF group Carriers of GG genotype of SREBF2 G1784C polymorphism had higher serum concentrations of total cholesterol and LDL-C after therapy. The SCAP A2386G polymorphism seems to be associated with higher concentrations of apoB in patients from HNF group prior to treatment with atorvastatin. The results suggest that the HMGCR, LDLR and NPC1L1 genes are regulated according to the metabolic status of the individual, and the expression rate of mRNA is influenced by SREBF2 G1784C and SCAP A2386G polymorphisms after atorvastatin therapy.
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Statin Pharmacotherapy in U.S. Nursing Homes

Mack, Deborah Sara 27 August 2020 (has links)
Background: Statins have questionable benefits among older adults with life-limiting illness. Statin use is widespread among U.S. older adults, but little is known about use in nursing homes. This dissertation was designed to identify the prevalence and predictors of statin pharmacotherapy use and discontinuation in U.S. nursing homes. Methods: Data sources (2011-2016) included: Minimum Data Set 3.0, Medicare administrative claims data, Provider of Service files, and Dartmouth Atlas files. Analyses included: descriptive statistics, multilevel modeling, and proportional change in cluster variations with adjustments to reduce confounding and model misspecification. Results: Approximately 36% of older adults admitted to U.S. nursing homes between 2015 – 2016 were actively using statins at the time of admission. Among long-stay residents with life-limiting illness, 34% were on statins at one time (2016; aged 65-75 years: 44%, >75 years: 31%). Statin use varied significantly by hospital referral regions, with most variation in the >75 age group. Limiting the sample to statin users, 20% discontinued statins within 30 days of nursing home admission. While discontinuation was positively associated with severity of life-limiting condition, the majority of residents remained on statins 30 days post-admission, including those with a < 6-month prognosis. Conclusion: Statin use is pervasive across US nursing homes and persists with life-limiting illness. Geographic variation appeared to coincide with clinical uncertainty, especially among adults >75 with few national guidelines. More needs to be done to prioritize statin deprescribing in nursing homes with research that identifies ways to facilitate improved patient-provider awareness and engagement in the discontinuation process.

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