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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.
61

Ethnic heterogeneity of the North-Swedish population : its origin and medical consequences

Nylander, Per-Olof January 1992 (has links)
Northern Sweden shows a unique population structure with remarkable geographical variations in the distribution of genetic disorders as well as genetic markers like blood groups, serum groups and red cell enzyme types. The present-day population of northern Sweden is a mixture of people of Finnish, Saamish (Lappish) and Central-Swedish origin. In this thesis the ethnic heterogeneity of the North-Swedish population (counties of Västerbotten and Norrbotten) was studied using genetic blood markers, and the epidemiological impact of the ethnic heterogeneity was exemplified by studying the geographical correlation between Finnish admixture and risk factors for cardiovascular diseases. The following results were found: 1 Two new ethnic marker genes were discovered: the GC*1F allele (GC serum groups) for Saamish influence and the TF*C3 allele (transferrin serum groups) for Finnish influence. 2 Regional gene frequency variations in the A1A2B0 blood groups, 6-phosphogluconate dehydrogenase (6-PGD) types and transferrin and GC serum groups were studied in a sample of 4100-5600 individuals from northern Sweden distributed according to birth place into 23 subpopulations. A significant regional heterogeneity was found in all systems. The ethnic marker genes (AB0*A2, GC*1F, TF*C3, PGD*C) showed clineal variations consistent with the expected patterns of Finnish and Saamish admixture. 3 Finnish and Saamish admixture was estimated in the 23 subpopulations using AB0*A2, GC*1F and PGD*C as Saamish markers and TF*C3, TF*DCHI, TF*B0-1 and SODI*2 as Finnish markers. The Saamish admixture varied between 0 and 34% and was strongest in the northern and northwestern parts of northern Sweden. The Finnish influence varied between 0 and 84% and was strongest in the northern and northeastern parts of the area. The ethnic marker genes showed significant geographical intercorrelations. 4 Hypercholesterolemia showed a significant heterogeneity between the 23 subpopulations, and there was a significant geographical covariation with the degree of Finnish admixture. These results are consistent with the hypothesis that Finnish genetic influence may contribute to the development of hypercholesterolemia and thereby to the increased rate of cardiovascular diseases found in northern Sweden. The results of this study suggest that in addition to the founder effect ethnic heterogeneity is an important determinant of the structure of the North-Swedish population. / <p>Diss. (sammanfattning) Umeå : Umeå universitet, 1992, härtill 7 uppsatser.</p> / digitalisering@umu.se
62

THE EFFECT OF CHOLESTEROL ON THE OSTEOBLAST RESPONSIVENESS TO HYDRODYNAMIC PRESSURE STIMULATION

Lough, Kristen 01 January 2015 (has links)
Hypercholesterolemia is a risk factor for osteoporosis but the underlying mechanism is unknown. Previous evidence suggests that osteoporosis results from an impaired regulation of osteoblasts by fluid pressure fluctuations in the bone matrix. Recently, our laboratory showed that enhanced cholesterol in the cell membrane, due to hypercholesterolemia, alters leukocyte mechanosensitivity. We predict a similar link between osteoblasts and hypercholesterolemia leading to osteoporosis. Specifically, we hypothesize that extracellular cholesterol modifies the osteoblast sensitivity to pressure. MC3T3-E1 cells were exposed to hydrodynamic pressures regimes (mean=40mmHg, amplitude=0-20mmHg, frequency=1Hz) for 1-12 hours. To assess the impact of membrane cholesterol enrichment, cells were pre-treated with 0-50 µg/mL cyclodextran:cholesterol conjugates. We assessed the pressure effects on mitosis and F-actin stress fiber formation (SFF) of cells. Exposure of cells to 50/30 mmHg pressure transiently increased the number of cells in the S- and G2M-phases of mitosis after 6 and 12 hours, respectively. Relative to controls, osteoblast-like cells exposed to all pressures exhibited significantly (p
63

I. Formal Synthesis of SCH 351448. II. Synthesis and Characterization of Largazole Analogues.

Park, Heekwang January 2012 (has links)
<p>Part I: Extensive studies for treating hypercholesterolemia, one of the major causes of human morbidity throughout the world, have led to the development of statin drugs-the most prevalent drug prescribed today. In addition to statins, SCH 351448 has attracted considerable interest from many synthetic groups as it is the only selective activator of low-density lipoprotein receptor (LDL-R) containing structural features such as a C2-symmetry and 2,6-cis-tetrahydropyrans. Even though direct dimerization has been the most efficient method for the construction of C2-symmetric macrodiolides, total syntheses of SCH 351448 were only achived by stepwise dimerizations. In this chapter, attempts were made to exploit the inherent C2-symmetric macrodioloide via direct dimerization using various single monomeric units, but they did not prove to be viable. Therefore, formal synthesis of SCH 351448 was accomplished through two tandem sequences; cross-metathesis/conjugate addition and allylic oxidation/conjugate addition reactions, to stereoselectively construct 2,6-cis-tetrahydropyrans embedded in SCH 351448. The 1,4-syn aldol and the Suzuki coupling reactions were effective for the construction of the monomeric units. This convergent route should be broadly applicable to the synthesis of a diverse set of analogues of SCH 351448 for further biological studies.</p><p>Part II: Histone deacetylases (HDACs) play a significant role in tumorigenesis and have been recognized as one of the target enzymes for cancer therapy. Extensive studies in small molecules inhibiting HDAC enzymes have resulted in pan-HDAC inhibitor suberoylanilide hydroxamic acid (SAHA) and class I HDAC inhibitor FK228, approved by FDA in 2006 and 2009, respectively. Recently, largazole, a natural product was isolated from Symploca sp. presented HDAC inhibitory activity. Due to its unique differential cytotoxicity, potency, and class selectivity, structure-activity relationship (SAR) studies of largazole have been achieved to improve the potency and class selectivity. In addition to such biological activities, pharmacokinetic characteristics and isoform selectivity should be improved for the therapeutic potential of cancer therapy. In this chapter, two types of largazole analogues were synthesized by a convergent route that involved an efficient and high yielding multistep sequence. The synthesis of three disulfide analogues to improve pharmacokinetics and five linker analogues to enhance HDAC isoform selectivity is disclosed. The evaluation of biological studies is in progress.</p> / Dissertation
64

Living with familial hypercholesterolaemia /

Hollman, Gunilla January 2003 (has links) (PDF)
Diss. (sammanfattning) Linköping : Univ., 2003. / Härtill 4 uppsatser.
65

Μελέτη των λειτουργιών μιας μεταλλαγμένης μορφής της απολιποπρωτεΐνης Ε με βελτιωμένες βιολογικές ιδιότητες

Φωτιάδου, Ελισάβετ 11 January 2011 (has links)
Η αθηρωματική νόσος είναι η κύρια αιτία καρδιαγγειακών νοσημάτων (CVD). Σύμφωνα με τον WHO το 2004 οι θάνατοι λόγω CVD ήταν 17.1 εκατομμύρια, το 29% των θανάτων παγκοσμίως. Η παθογένεια της νόσου είναι πολυπαραγοντική και οφείλεται σε περιβαλλοντικά και γενετικά αίτια, ένα από τα οποία είναι οι λιπιδαιμικές διαταραχές. Μελέτες τόσο in vitro όσο και in vivo σε ανθρώπους και πειραματόζωα καταδεικνύουν την απολιποπρωτεΐνη Ε (ApoE) ως κομβικό μόριο στη μεταφορά και το μεταβολισμό των λιποπρωτεϊνών, οι οποίες αποτελούν τα μεταφορικά μέσα των λιπιδίων. Η ΑpoE εκφράζεται σε ποικίλους ιστούς, όπως ο λιπώδης ιστός, τα ενδοθηλιακά κύτταρα, τα μακροφάγα και ο εγκέφαλος, αν και η κύρια θέση παραγωγής της είναι το ήπαρ. Στις δράσεις της ΑpoE περιλαμβάνονται η ηπατική πρόσληψη των λιποπρωτεϊνών, η ενεργοποίηση ενζύμων που συμμετέχουν στον μεταβολισμό των λιποπρωτεϊνών (LCAT, CETP, HL) η μεταφορά χοληστερόλης από περιφερικούς ιστούς στο ήπαρ με στόχο την κάθαρση και τελικώς τη ρύθμιση της ομοιόστασης του ισοζυγίου της χοληστερόλης στο αίμα. Η απομάκρυνση VLDL και υπολειμμάτων χυλομικρών από την κυκλοφορία μέσω της αγρίου τύπου (wt) ΑpoE προϋποθέτει την ύπαρξη λειτουργικών υποδοχέων LDLr. Στους ανθρώπους μεταλλάξεις ή πλήρης έλλειψη έκφρασης του LDLr οδηγεί στη εμφάνιση Οικογενής υπερχοληστερολαιμίας (FH). Στην περίπτωση της ομόζυγης Οικογενής υπερχοληστερολαιμίας (HoFH) οι ήδη υπάρχουσες φαρμακολογικές προσεγγίσεις είναι αναποτελεσματικές, με συνέπεια οι ασθενείς να καταλήγουν πρόωρα. Παρά τις ωφέλιμες δράσεις της wt ApoE στο μεταβολισμό των λιποπρωτεϊνών, η θεραπευτική της αξία είναι περιορισμένη καθώς σε συγκεντρώσεις άνω των φυσιολογικών επιπέδων στο πλάσμα επάγει συνδυαστική υπερλιπιδαιμία. Η διερεύνηση της δομής και των λειτουργικών θέσεων της ΑpoΕ οδήγησε στην κατασκευή μιας τεχνητά μεταλλαγμένης μορφής, της ΑpoE4mut1 , η οποία όχι μόνο δεν προκαλεί διαταραχή λιπιδίων αλλά έχει και βελτιωμένες δράσεις σε σχέση με την wt ΑpoE. Η έρευνα που αναλύεται στην εργασία αυτή ξεκίνησε με σκοπό να μελετηθεί η αναγκαιότητα έκφρασης λειτουργικού υποδοχεά LDLr για την εκδήλωση των βελτιωμένων βιολογικών δράσεων της ΑpoE4mut1. Συγκεκριμένα, σε υπερχοληστερολαιμικά ποντίκια με ταυτόχρονη έλλειψη στην ΑpoE και τον LDLr (ApoE-/- x LDLr-/-) χορήγηση της μεταλλαγμένης μορφής ΑpoE4mut1 μέσω αδενοϊών οδήγησε σε μείωση των επιπέδων χοληστερόλης στο αίμα τους. Το γεγονός αυτό καταδεικνύει μια νέα ιδιότητα της ΑpoE4mut1 πολλά υποσχόμενη όσον αφορά στην ανακάλυψη νέων θεραπευτικών κατευθύνσεων για την ομόζυγη οικογενή υπερχοληστερολαιμία (ΗoFH). / Atherosclerosis is a focal disease that constitutes the main cause of coronary heart disease (CHD) and cardiovascular diseases (CVD). According to WHO an estimated 17.1 million people died from CVDs in 2004, representing 29% of all global deaths. The initial formation and progression of atheromatic lesions involves a complex interplay of both genetic and environmental factors, such as dyslipidemias. In vitro and in vivo studies, both in animal models and humans, have established that apolipoprotein E has a key role in the metabolism of lipoproteins, which are the main transport vehicles of the lipids in the circulation. ApoE is mainly synthesized by the liver and secondary by other tissues, such as fat tissue, macrophages, brain. The protein is involved in the efficient hepatic uptake of lipoprotein particles, the activation of enzymes, such as LCAT, CETP, which participate to metabolic pathways of lipoproteins, and the stimulation of reverse cholesterol transport from peripheral tissues to the liver. Therefore, ApoE is capable of regulating cholesterol homeostasis in plasma. The expression of functional LDLr is required by wild type ApoE, in order to perform the clearance of lipoprotein particles. In humans mutations or total deficiency in LDLr result in a disease called Familial Hypercholesterolemia (FH). Homozygote patients with FH (HoFH) do not benefit from the conventional therapies and die prematurely. Despite the central role of wt ApoE in the metabolism of lipoprotein particles, its therapeutic value is reduced due to the limitation that at concentrations higher than physiological, plasma ApoE induces combined hyperlipidemia. Studies on the structure-function relationship of the protein resulted in the generation of a mutant variant ApoE4mut1, which has improved functions regarding wt ApoE4 and does not induce hypertriglyceridemia. The present study was initiated in order to determine whether the improved functions of ApoE4mut1 require the expression of LDLr. The results demonstrated new possible interventions for the treatment of HoFH. In particular, hypercholesterolemic mice with deficiency both in ApoE and LDLr genes (ApoE-/- x LDLr-/-), which expressed through adenovirusmediated gene transfer the mutant ApoE4mut1, showed a decrease in the cholesterol levels. This finding may lead to important therapeutic applications as a new treatment for HoFH when gene therapy becomes a reality in the future.
66

Avaliação do papel da fibrina rica em plaquetas em defeito crítico cirurgicamente criado em calota de ratos induzidos à hipercolesterolemia tratados ou não com atorvastatina / Evaluation of the role of Platelet Rich Fibrin in surgical critical-size calvarial defect in rats with diet-induced hypercholesterolemia treated or not with atorvastatin

Oliva, André Hergesel de [UNESP] 06 February 2018 (has links)
Submitted by André Hergesel de Oliva null (holivaandre@gmail.com) on 2018-02-19T13:16:08Z No. of bitstreams: 1 Dissertação_MestradoCORRIGIDO.pdf: 2514302 bytes, checksum: 2de51633e693041838c21d79e951b406 (MD5) / Approved for entry into archive by Ana Paula Rimoli de Oliveira null (anapaula@foa.unesp.br) on 2018-02-19T14:23:57Z (GMT) No. of bitstreams: 1 oliva_ah_me_araca_int.pdf: 2514302 bytes, checksum: 2de51633e693041838c21d79e951b406 (MD5) / Made available in DSpace on 2018-02-19T14:23:57Z (GMT). No. of bitstreams: 1 oliva_ah_me_araca_int.pdf: 2514302 bytes, checksum: 2de51633e693041838c21d79e951b406 (MD5) Previous issue date: 2018-02-06 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Esse estudo objetivou-se em avaliar o papel da membrana de fibrina rica em plaquetas na reparação óssea em defeito crítico de calota de ratos induzidos à hipercolesterolemia, bem como a atuação do tratamento de atorvastatina nesse processo. Quarenta defeitos críticos de 6 mm de diâmetro foram criados em calotas cranianas de ratos. Cada defeito foi aleatoriamente dividido em 8 grupos experimentais (GC, GCPRF, GCA, GCH, GHA, GPRFA, GPRFH, GPRFHA), avaliados aos 28 dias pós-operatórios com análises histológica e microtomográfica. Os resultados mostraram que houve formação óssea em todos os grupos analisados. O grupo GPRFH apresentou formação óssea mais acentuada com relação aos demais grupos. Dos grupos em que foi administrado atorvastatina, o GPRFHA apresentou maior taxa de formação óssea (p < 0,05). Com a metodologia utilizada, a fibrina rica em plaquetas, quando associada à condição de hipercolesterolemia, induziu ao aumento da formação óssea. / Objectives: The aim of this study was to evaluate the efficacy of Platelet Rich Fibrin (PRF) in the healing process of surgically created critical-size defects in rat calvarial induced to hypercholesterolemia treated or not with atorvastatin. Materials and method: 40 critical defects were created with 6 mm diameter calvaria of rats. Each defect was randomly divided into eight experimental groups (GC, GCPRF, GCA, GCH, GHA, GPRFA, GPRFH, GPRFHA), evaluated at 28 postoperative days for histomorphometry and microtomography. Results: The results showed new bone formation in all groups. The GPRFH group just did differ from all groups in the new bone formation (p < 0.05). Among the groups treated with atorvastatin, the GPRFHA group showed the highest bone formation rate. Conclusion: With the methodology used, the platelet-rich fibrin associated with the hypercholesterolemia induced to new bone formation. Clinical relevance: Based on these results, it is necessary to unveil the mechanisms of the association of platelet-rich fibrin with hypercholesterolemia and how it interferes in PRF microstructure and bone regeneration, to confer clinical predictability in patients in this condition who will undergo bone reconstruction and implant rehabilitation.
67

Efeito do treinamento físico aeróbio na reatividade vascular da artéria ilíaca em camundongos LDL-/- / Effect of aerobic exercise training on vascular reactivity of the iliac artery in LDL -/- mice

Garcia, Nádia Fagundes Nádia [UNESP] 29 March 2016 (has links)
Submitted by NADIA FAGUNDES GARCIA null (nadia.garcia@usp.br) on 2016-04-26T14:05:01Z No. of bitstreams: 1 Dissertação_Nádia_final.pdf: 1655190 bytes, checksum: 3ec5b191317646b34cbfef983fcdf111 (MD5) / Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2016-04-29T15:08:25Z (GMT) No. of bitstreams: 1 garcia_nf_me_rcla.pdf: 1655190 bytes, checksum: 3ec5b191317646b34cbfef983fcdf111 (MD5) / Made available in DSpace on 2016-04-29T15:08:25Z (GMT). No. of bitstreams: 1 garcia_nf_me_rcla.pdf: 1655190 bytes, checksum: 3ec5b191317646b34cbfef983fcdf111 (MD5) Previous issue date: 2016-03-29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A inatividade física e as dislipidemias são considerados fatores de risco para a gênese das doenças cardiovasculares. Estudos em animais mostram que o consumo de dieta contendo alto teor de lipídios leva à diminuição da resposta relaxante dependente do endotélio, o que pode ser prevenido pela realização de exercício físico. Entretanto, a maioria dos estudos investigou os efeitos do exercício físico em artérias de maior calibre e em modelos de dislipidemia induzida por dieta. Há escassez de estudos que avaliam os efeitos do exercício físico em artéria de menor calibre e, principalmente, em modelo que mimetiza a hipercolesterolemia familiar (HF). Portanto, o objetivo do presente estudo foi avaliar o efeito do treinamento físico aeróbio de moderada intensidade na reatividade vascular da artéria ilíaca em camundongos knockout para o receptor de LDL alimentados com dieta hiperlipídica. Foram utilizados camundongos wild type e knockout para o receptor de LDL (LDLR-/-) divididos em quatro grupos experimentais: wild type sedentário (WT), wild type treinado (WT/Ex), knockout sedentário (KO) e knockout treinado (KO/Ex). Os grupos WT foram alimentados com ração balanceada e os grupos KO com dieta hiperlipídica (38% lipídios). Os grupos WT/Ex e KO/Ex realizaram corrida em esteira (60-70%Vmax, 5 dias/semana, 60 min) durante oito semanas. A reatividade vascular em artéria ilíaca foi verificada através de curvas concentração-resposta a acetilcolina (ACh), nitroprussiato de sódio (SNP), fenilefrina (PHE) e ao análogo do tromboxano A2 (U46619). A determinação da produção de óxido nítrico (NO) foi realizada pela análise de fluorescência ao 4,5-diaminofluoresceína (DAF-2) e a produção de ânion superóxido pela análise da fluorescência derivada da oxidação da dihidroetidina (DHE). Foi quantificada a glicose, o colesterol total e os triglicerídeos sanguíneos. O grupo KO aumentou em 640% o ganho de peso corporal, 510% a gordura epididimal, 35% a glicose, 180% o colesterol total e 99% os triglicerídeos comparado ao grupo WT e o treinamento físico aeróbio foi eficaz em prevenir o ganho de peso e a gordura epididimal no grupo KO/Ex (167% e 121%, respectivamente). Nenhuma alteração foi verificada na glicose, colesterol total e triglicerídeos no soro. O relaxamento máximo induzido por ACh foi reduzido em 24% no grupo KO comparado ao grupo WT, sendo esta resposta normalizada no grupo KO/Ex, sem alteração na potência. A resposta máxima a PHE foi 65% maior, e resposta da potência foi 3 vezes maior na artéria ilíaca de animais do grupo KO comparado ao grupo WT. Nenhuma alteração na resposta foi encontrada aos agentes SNP e U46619. A produção de NO foi 47% menor no grupo KO comparado ao WT e a produção de espécies reativas de oxigênio (ERO) foi 48% maior no grupo KO comparado ao grupo WT. O treinamento físico preveniu o aumento na produção de ERO no grupo KO/Ex. Em conclusão, o exercício físico aeróbio, realizado por oito semanas, preveniu a disfunção endotelial na artéria ilíaca de camundongos LDLR-/- alimentados com dieta hiperlipídica. Este achado pode estar relacionado à menor produção de ERO, o que aumentaria a biodisponibilidade do NO. / Physical inactivity and dyslipidemia are considered risk factors for cardiovascular disease. A decrease in endothelium-dependent relaxation response, which can be prevented by physical exercise, had been showing in animals fed with high fat diet. However, most studies investigated the effects of physical exercise on large-caliber arteries using models of diet induced dyslipidemia. There are few studies that evaluate the effects of physical exercise in small-caliber artery and, mainly, in a model that mimics familial hypercholesterolemia (FH). Therefore, the aim of this study was to evaluate the effect of moderate intensity exercise training on vascular reactivity of iliac artery in FH model using mice lacking LDL receptor. Wild type and knockout mice (LDLR-/-) were divided into four groups: sedentary control (WT), trained control (WT/Ex), sedentary knockout (KO) and trained knockout (KO/Ex). Control groups were fed with standard chow and knockout groups with high fat diet. Trained groups ran on a treadmill (60-70% Vmax, 60 min, 5 days/week for 8 weeks). Concentration-response curves to acetylcholine (ACh), sodium nitroprusside (SNP), phenylephrine (PHE) and thromboxane A2 analogue (U46619) were done in iliac artery rings. Arterial production of nitric oxide and oxygen reactive species formation were assessed using fluorescence analysis (DAF-2 and DHE). Serum concentration of glucose, total cholesterol and triglyceride were determined using commercial kits. After eight weeks, the KO group had higher body weight gain (around 640%), epididymal fat (510%), glucose (35%), total cholesterol (180%) and triglycerides (99%) compared with WT group. Exercise training was effective to prevent body weight and epididymal fat gain in KO/Ex group (less 167% and 121%, respectively). No changes were observed in glucose, total cholesterol and triglycerides concentration. KO animals had lower maximal response evoked by ACh (about 24%) and higher maximal response to PHE (about 65%) compared with WT group. Exercise training prevented these alterations since KO/Ex group had vascular response similar to WT and WT/Ex groups. Endothelial dysfunction observed in KO group could be related to the reduced production of NO (about 47%) and the increased formation of oxygen reactive species (about 48%). These features were partially prevented by exercise training, KO/Ex group had lower formation of oxygen species and a slight higher NO prodution compared with KO group. In conclusion, aerobic exercise training carried out for eight weeks, prevented endothelial dysfunction in iliac artery from LDLR-/- mice fed with high fat diet. This finding could be related to the lower formation of reactive oxygen species in situ that increases the NO bioavailability.
68

Estudo experimental do efeito da proteína glicinina da soja (Glycine max L.) no metabolismo do colesterol /

Fassini, Priscila Giácomo. January 2010 (has links)
Orientador: Aureluce Demonte / Banca: Valdir Augusto Neves / Banca: Olga Luisa Tavano / Resumo: A globulina 11S (glicinina) é a proteína predominante da soja e tem sido extensivamente caracterizada. Além das suas propriedades nutricionais, há evidências de sua participação na redução das concentrações lipídicas do soro. Por outro lado, o fármaco rosuvastatina tem suas ações demonstradas no metabolismo lipídico, por reduzir a fração LDL-colesterol, bloqueando a chave do processo de produção de colesterol hepático. Embora a eficiência do medicamento seja comprovada, é importante considerar a alimentação como uma possível ação somatória, tendo em vista os graves problemas ocasionados pelas alterações lipídicas no organismo. À vista do exposto, a presente pesquisa teve por objetivo estudar o efeito da glicinina isolada da soja em comparação ao fármaco rosuvastatina em animais submetidos à dieta hipercolesterolêmica. Foram elaboradas duas dietas, uma padrão, contendo caseína como proteína (AIN-93M), e outra hipercolesterolêmica, composta pela dieta padrão adicionada de 1% de colesterol e 0.5% de ácido cólico. A proteína glicinina de soja (300 mg/kg de peso corporal) e o fármaco rosuvastatina (10 mg/Kg de peso corporal), ambos solubilizados em solução salina, foram administrados por gavagem. Foram utilizados ratos machos Wistar mantidos em gaiolas individuais sob condições adequadas. Os animais foram separados em cinco grupos (n = 9): 1) grupo padrão (STD) recebeu a dieta padrão; 2) grupo hipercolesterolêmico (HC) recebeu apenas a dieta hipercolesterolêmica; 3) grupo (HC+11S) recebeu a dieta e a proteína glicinina da soja; 4) grupo (HC+ROS) recebeu a dieta e o fármaco; 5) grupo (HC+ROS+11S) recebeu a dieta, a proteína e o fármaco. Ao final de 28 dias os animais foram sacrificados e o sangue removido para análises bioquímicas de colesterol total (CT), HDL-colesterol (HDL-C) e triglicérides (TG) plasmático, CT e TG hepático... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The 11S globulin (glycinin) is the predominant protein of soybeans and has been extensively characterized. In addition to its nutritional properties there is evidence of its action in reducing serum lipid concentrations. Moreover, the drug rosuvastatin has demonstrated its effects on lipid metabolism, by reducing LDL cholesterol and blocking the key enzyme in the process of cholesterol production in the liver. Although the efficiency of the drug is proven, it is important to consider the sum of its action and that of food, in view of the serious problems caused by changes in body fat. In view of the foregoing, the aim of the present study was to investigate the effects of isolated soy glycinin, as compared to the drug rosuvastatin, in rats subjected to a hypercholesterolemic diet. Two diets were prepared, a standard diet, containing casein as protein (AIN-93M), and a hypercholesterolemic, consisting of the standard diet plus 1% cholesterol and 0.5% cholic acid. The glycinin (300 mg/kg body weight) and the rosuvastatin (10 mg/kg body weight), both dissolved in saline, were administered by gavage. Male Wistar rats were kept in individual cages under appropriate conditions. The animals were divided into five groups (n=9): 1) standard group (STD) received the standard diet; 2) hypercholesterolemic group (HC) received the hypercholesterolemic diet alone; 3) group HC+11S received the HC diet and the glycinin; 4) group HC+ROS received the HC diet and the drug; 5) group HC+ROS+11S received the HC diet, the protein and the drug. After 28 days, the animals were sacrificed and the blood removed for biochemical analysis of total plasma cholesterol (TC), HDL-cholesterol (HDL-C) and triglycerides (TG), and hepatic TC and TG. The results indicated that the experimental HC diet was able to induce hypercholesterolemia and that a single daily dose of the isolated protein was appropriate for a comparative... (Complete abstract click electronic access below) / Mestre
69

Ação dos fitoesteróis sobre lesão aterosclerótica em camundongos com ablação gênica do receptor de LDL / Phytosterols effects over atherosclerotic lesion in mice with ablation of the LDL receptor gene

Renata de Paula Assis Bombo 13 August 2014 (has links)
Introdução: Os fitoesteróis (FE) são reconhecidos por reduzirem a concentração plasmática de LDL-colesterol, sendo importantes coadjuvantes no tratamento da hipercolesterolemia moderada. Entretanto, estudos publicados recentemente demonstram resultados conflitantes em relação à eficiência dos FE na prevenção da aterosclerose. Além disso, algumas investigações evidenciaram que o aumento da concentração plasmática de FE está positivamente relacionado ao risco de desenvolvimento de aterosclerose. Com a finalidade de elucidar a sua ação sobre esses parâmetros, o objetivo deste estudo foi avaliar os efeitos da suplementação de FE no desenvolvimento da aterosclerose em camundongos com ablação gênica para o receptor de LDL (LDLr-KO). Métodos: Os animais foram alimentados durante 16 semanas, com dieta rica em gordura (40% do valor calórico total da dieta), suplementada (grupo FE; 2%, n=10) ou não (Controle; n=10) com FE. Foram avaliadas as concentrações plasmáticas e hepáticas de colesterol, triglicérides, FE (beta-sitosterol, campesterol e latosterol). Na aorta dos animais, determinaram-se as concentrações de colesterol total, colesterol livre e éster e FE, além do infiltrado de macrófagos e infiltrado de lípides. Nos macrófagos do peritôneo dos animais, os quais assemelham-se aos presentes na artéria, avaliou-se a expressão de RNA mensageiro dos genes envolvidos no efluxo e influxo de colesterol (ABCA1, ABCG1, LOX1 e CD36). Também determinou-se as concentrações de FE no intestino e baço dos animais. Resultados: Conforme esperado, o consumo de FE induziu elevação plasmática dos principais FE, campesterol e de beta-sitosterol, reduzindo a concentração de colesterol no plasma. Houve aumento nas concentrações hepáticas de triglicérides e FE, entretanto, não foram observadas diferenças entre os grupos nas expressões de RNA mensageiro de genes lipolíticos (CPT, PPAR alfa) e lipogênicos (SREBP1-c, MTP, LXR e PPAR gamma) no fígado. Não houve, também, alteração no SREBP2, gene relacionado à síntese de colesterol. O conteúdo de colesterol total na artéria foi menor nos animais do grupo FE, não diferindo entre as formas livre e éster. As concentrações de FE na artéria foram iguais entre os grupos. A área de lesão no grupo FE foi menor em relação ao grupo-controle. A suplementação com FE induziu redução na expressão de RNA mensageiro de ABCG1, não interferindo na expressão dos outros genes estudados na artéria. Conclusão: Os achados deste estudo demonstram que a elevação de FE no plasma não induziu o seu acúmulo na parede da artéria e preveniu o desenvolvimento da aterosclerose / Introduction: The plasma cholesterol-reducing effect of hytosterols (PS) is well recognized and they are considered important adjuncts in the treatment of moderate hypercholesterolemia. However, recent studies have shown conflicting results regarding the efficiency of PS in the prevention of atherosclerosis. In addition, some studies showed that the increase in plasma PS concentration is positively correlated to the risk of atherosclerosis. In order to elucidate its action on these parameters, the objective of this study was to evaluate the effects of PS supplementation in the development of atherosclerosis in LDL receptor knock-out mice (LDLr -KO). Methods: The animals were fed during 16 weeks with high fat diet (40 % of calories as fat), supplemented (PS group, 2%, n = 10) or not (Control, n = 10) with PS. Plasma and liver concentrations of cholesterol, triglycerides, PS (beta - sitosterol, campesterol and lathosterol) were evaluated. In the aorta of the animals, the concentrations of total cholesterol, free cholesterol, cholesterol ester and PS, besides macrophage and lipids infiltration were determined. The mRNA expression of genes involved in cholesterol efflux and influx (ABCA1, ABCG1, LOX1 and CD36) were evaluated, in peritoneum macrophage, which resemble those present in the artery. It was also determined the intestine and spleen PS concentrations from the animals of both groups. Results: As expected, PS supplementation induced increasing plasma concentration of the main PS, campesterol and beta -sitosterol and reducing cholesterol plasma concentration. It was observed an increase so intestine and spleen PS concentrations. There was an increase in hepatic triglyceride concentrations and PS, however, no differences were observed between the groups of hepatic mRNA expression of lipolytic (CPT, PPARalfa) and lipogenic genes (SREBP1c, MTP, CPT, LXR, and PPAR gamma). There was no difference on SREBP2, gene related to cholesterol synthesis. The content of total cholesterol in the artery was lower in PS group animals however did not differ between the free and ester forms. Artery PS concentrations did not differ between groups. The lesion area in the PS group was lower than in the control group. PS supplementation induced reduction in mRNA expression of ABCG1, not affecting the expression of other genes studied in artery. Conclusion: The findings of this study demonstrate that the elevation of plasma PS concentration did not induce its accumulation in the arterial wall and prevented the development of atherosclerosis
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Efeitos da associação de quimioterápicos na regressão de placa aterosclerótica e no perfil de marcadores inflamatórios em coelhos / Effects of chemotherapy association on atherosclerotic plaque regression and inflammatory markers profile in rabbits

Fernando Luiz Torres Gomes 21 October 2015 (has links)
A aterosclerose é considerada, hoje, doença inflamatória e com intensa proliferação celular, daí o racional de se usar medicamentos antiproliferativos e com ação anti-inflamatória como o paclitaxel (PTX) e o metotrexato (MTX) no tratamento dessa condição. A nanoemulsão lipídica (LDE), de composição semelhante à da lipoproteína de baixa densidade (LDL), se liga a receptores de LDL após sua injeção endovenosa na corrente sanguínea. Como tais receptores estão superexpressos em células com altas taxas de proliferação, como ocorre no câncer e na aterosclerose, a LDE pode ser usada como veículo para direcionar agentes antiproliferativos a essas células, aumentando a sua eficácia e diminuindo a toxicidade. O paclitaxel é um quimioterápico com ação antiproliferativa usado em vários tipos de câncer e recobrindo stents farmacológicos, trabalhos anteriores, usando coelhos submetidos a uma dieta aterogênica, nos animais tratados com LDE-PTX houve redução de 60% da área lesionada. O metrotexato, além de ser usado em vários esquemas quimioterápicos, possui, também, ação anti-inflamatória, sendo usado em doenças inflamatórias crônicas, como a artrite reumatoide. Em outro estudo envolvendo, coelhos hipercolesterolêmicos, o uso de MTX comercial por 4 semanas demonstrou uma redução de 75% na área de placa aterosclerótica. Esse estudo tem por objetivo avaliar macroscopicamente a eficácia das terapias quimioterápicas combinada, composta de PTX-LDE com MTX-LDE, e monoterapia, apenas com PTX-LDE, na regressão da aterosclerose experimental. No presente trabalho, vinte e oito coelhos machos da raça New Zealand receberam dieta rica em colesterol a 1% durante 8 semanas. Depois desse período, foram divididos em quatro grupos: grupo CONTROLE, que foi sacrificado e as aortas fixadas para análise posterior, grupo DIETA, que apenas teve a ração enriquecida com colesterol a 1% suspensa, PTX, que recebeu tratamento com injeções endovenosas semanais de LDE-paclitaxel na dose de 4 mg/kg por 8 semanas, e PTX+MTX, que recebeu LDE-paclitaxel e LDE-metotrexato na dose de 4 mg/kg/semana por 8 semanas. Foram avaliados perfil hematológico, lipídico, bioquímico, ponderal e o consumo de ração. Após a eutanásia, foram medidas as lesões ateroscleróticas macroscópicas nas aortas dos coelhos. Em seguida, o arco aórtico foi analisado por morfometria e por imuno-histoquímica. Os marcadores inflamatórios foram analisados no plasma, por ELISA e por meio de expressão gênica por Qrt-pcr. Observou-se que não houve diferença no perfil ponderal e no consumo de ração entre os grupos de estudo. Não houve toxicidade hematológica, hepática e renal relacionada ao tratamento. No perfil lipídico, ao final do estudo, as concentrações de colesterol total, não HDL-C e triglicerídeos aumentaram significativamente em todos os grupos. Houve uma marcante regressão na área de placa aterosclerótica nos coelhos tratados com LDE-paclitaxel, da ordem de 64% e mais marcante no grupo LDE-metotrexato de 71%, quando comparados ao grupo CONTROLE. Na comparação com o grupo DIETA, houve, também, regressão, de 49% nos coelhos do grupo PTX e de 59% no grupo PTX+MTX. O tratamento quimioterápico também mostrou ação antiaterosclerótica nos outros parâmetros avaliados, destacando a intensa redução na relação íntima-média das aortas, na expressão proteica de MMP-9 e da redução na expressão gênica de TNF-? em relação ao grupo DIETA. Portanto, o tratamento quimioterápico com PTX e MTX associado à LDE possui potencial para uso clínico em pacientes com doença aterosclerótica, sendo muito eficaz e com boa tolerabilidade / Atherosclerosis is nowadays considered as an inflammatory disease with intense cell proliferation, hence the rationale of using antiproliferative drugs with an anti-inflammatory action such as paclitaxel (PTX) and methotrexate (MTX) in the treatment of this condition. The lipid nanoemulsion (LDE), with a similar composition to low density lipoprotein (LDL) binds to LDL receptors after their intravenous injection into the bloodstream. Since such receptors are overexpressed in cells with high proliferation rates, such as occurs in cancer and atherosclerosis, LDE can be used as a vehicle to direct antiproliferative agents to these cells, increasing their efficacy and reducing toxicity. Paclitaxel is a chemotherapeutic drug with an anti-proliferative action used in various types of cancer and drug-eluting stents. In previous studies using rabbits subjected to an atherogenic diet, animals treated with LDE-PTX had a 60% reduction in the injured area. Methotrexate in addition to being used in various chemotherapy regimens also has an anti-inflammatory action and is used for chronic inflammatory diseases such as rheumatoid arthritis; another study involving hypercholesterolemic rabbits using commercial MTX for 4 weeks showed a 75% reduction of the atherosclerotic plaque area. This study aims to evaluate the effectiveness of combined chemotherapy treatments, composed of PTX-LDE with MTX-LDE, and PTX-LDE in monotherapy, on the regression of experimental atherosclerosis. In this study, twenty eight male New Zealand breed rabbits received a diet enriched with 1% cholesterol for 8 weeks. After that time, they were divided into four groups: the CONTROL group, which was sacrificed and the aortas kept for later analysis, the DIET group, which only had the diet supplemented with 1% cholesterol suspended; the PTX group which received treatment with weekly intravenous injections of LDE paclitaxel, at a dose of 4 mg/kg for 8 weeks and the PTX+MTX group which received PTX - LDE + MTX-LDE at a dose of 4 mg/kg per week for 8 weeks. The hematological, lipid, biochemical, weight and food intake profiles were evaluated. After euthanasia, macroscopic atherosclerotic lesions in the aortas of the rabbits were measured. Then, the aortic arch was analyzed by morphology and immunohistochemistry. The inflammatory markers were analyzed in the plasma by ELISA and gene expression by qRT-PCR. There was no difference in weight profile and feed intake among the study groups. There was no hematological, hepatic or renal toxicity related to treatment. The lipid profiles of all the groups at the end of the study showed significantly increased concentrations of total cholesterol, non-HDL-C and triglyceride levels. There was a marked regression of 64% in the atherosclerotic plaque area, in the LDE-paclitaxel treated rabbits, and an even more striking 71% in the LDE-methotraxate group compared to the CONTROL group. There was also regression when compared to the DIET group, 49% in rabbits from the PTX group and 59% in the PTX+MTX group. The chemotherapy also showed an anti-atherosclerotic action in the other evaluated parameters, especially notable were the intense reduction in the intima-media ratio of the aortas in protein expression of MMP-9 and the reduction in gene expression of TNF-alpha compared to the DIET group. Therefore, chemotherapy with PTX and MTX associated with LDE, has potential for clinical use in patients with atherosclerotic disease, as it is very effective and well tolerated

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