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Lipid Transfer Inhibitor Protein (Apolipoprotein F) Concentration in Normolipidemic and Hyperlipidemic SubjectsMorton, Richard, Gnizak, Hannah M., Greene, Diane J., Cho, Kyung Hyun, Paromov, Victor M. 01 January 2008 (has links)
Lipid transfer inhibitor protein (LTIP) is an important regulator of cholesteryl ester transfer protein function. We report the development of an immunoassay for LTIP and its use to quantify LTIP in plasma of varying lipid contents. A rabbit antibody against bacterially produced recombinant LTIP detected two LTIP isoforms in plasma differing in carbohydrate content. This antibody was used in a competitive, enzyme-linked immunoassay that uses partially purified LTIP bound to microtiter plates. To optimize LTIP immunoreactivity, plasma samples required preincubation in 1% Tween-20 and 0.5% Nonidet P-40. In normolipidemic plasma, LTIP averaged 83.5 mg/ml. LTIP was 31% higher in males than in females. LTIP was positively associated with HDL cholesterol in normolipidemic males but not in females. In hypertriglyceridemic males, LTIP was only 56% of control values, whereas in hypertriglyceridemic females, LTIP tended to increase. Additionally, in males with normal cholesterol and triglyceride (TG) ≤ 200 mg/dl, LTIP varied inversely with plasma TG. Overall, we have confirmed the negative association between plasma TG levels and LTIP previously suggested by a small data set, but now we demonstrate that this effect is seen only in males. The mechanisms underlying this gender-specific response to TG, and why LTIP and HDL levels correlate in males but not in females, remain to be determined.
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Διερεύνηση της συσχέτισης των πολυμορφισμών των α2Β αδρενεργικών υποδοχέων και της Cept με τον κίνδυνο της υποτροπής ισχαιμίας μετά από αγγειοπλαστική στεφανιαίων αρτηριώνΠατσούρας, Νικόλαος 11 September 2008 (has links)
Η στεφανιαία νόσος αποτελεί ένα από τα πιο συχνά αίτια νοσηρότητας και θνητότητας στο γενικό πληθυσμό. Ένα μεγάλο ποσοστό από τους ασθενείς με στεφανιαία νόσο οδηγείται σε αγγειοπλαστική στεφανιαίων αρτηριών (PTCA) με ή χωρίς εμφύτευση stent, όταν η στένωση στο αγγείο είναι ≥ 70-75%. Παρά την πρόοδο στον τομέα της αγγειοπλαστικής, με τη χρήση των drug-eluting stents και την ελάττωση της επαναστένωσης σε ποσοστό <5-10%, το υψηλό ποσοστό (20-25%) επαναστένωσης παραμένει η Αχίλλειος πτέρνα στα συμβατικά, μεταλλικά(bare)stents.
Η χρήση των drug-eluting stents περιορίζεται σε περιπτώσεις με επαναστένωση, σε σακχαροδιαβητικούς και σε υψηλού κινδύνου βλάβες για επαναστένωση. Τα μεγάλα ποσοστά όψιμης επαναστένωσης(≥ 9-10%) και το υψηλό κόστος τους, κάνουν ακόμα πιο επιτακτική την ανάγκη εντατικοποίησης της έρευνας προς την κατεύθυνση εντοπισμού παραγόντων σχετιζόμενων με την επαναστένωση.
Σκοπός της εργασίας μας ήταν να διερευνήσει τον πιθανό ρόλο πολυμορφισμών γονιδίων στην υποτροπή ισχαιμίας μετά από αγγειοπλαστική στεφανιαίων αρτηριών και εμφύτευση μεταλλικών stents.
Συγκεκριμένα, εξετάσθηκε αναλυτικά ο γενετικός πολυμορφισμός των γονιδίων α2Β-αδρενεργικού υποδοχέα και της CETP(πρωτεΐνη μεταφοράς εστέρων χοληστερόλης).
Η υπόθεση στηρίχτηκε στο γεγονός ότι σε μια σημαντική μελέτη 912 αρρένων Φινλανδών μέσης ηλικίας, αποδείχτηκε ότι ο D/D γονότυπος σε σχέση με τον I/D γονότυπο και τον I/I γονότυπο, εμφανίζει 2,5 φορές μεγαλύτερο κίνδυνο για οξέα στεφανιαία επεισόδια, συμπεριλαμβανομένου του εμφράγματος μυοκαρδίου.
Η εκσεσημασμένη αγγειοσύσπαση, τόσο στην περιφέρεια, όσο και
στις στεφανιαίες αρτηρίες μέσω του πολυμορφισμού του γονιδίου α2Β που θεωρείται πιθανό αίτιο για τα οξέα στεφανιαία επεισόδια, μαζί με το σημαντικό ρόλο του α2Β αδρενεργικού υποδοχέα στην υπερπλασία και μετανάστευση των λείων μυϊκών κυττάρων, πιθανόν να έχει μεγάλη συμβολή στη διεργασία της υποτροπής ισχαιμίας.
Μελετήσαμε προοπτικά 96 Έλληνες που υπέστησαν επιτυχή PTCA και εμφύτευση stents, εκ των οποίων 81 ήταν άνδρες και 15 γυναίκες(μέση ηλικία ± σταθερά απόκλιση=57,7± 10,1 ετών, με όρια 37-76 ετών) που προσήλθαν με συμπτωματική στεφανιαία νόσο. Όλοι οι παραπάνω ασθενείς συμμετείχαν στη μελέτη μεταξύ των ετών 2001 και 2003 και παρακολουθήθηκαν κλινικά για 6-8 μήνες μετά από μια επιτυχή τεχνική διάνοιξης του αποφραγμένου αγγείου. Αμέσως μετά την PTCA και για ένα(1) μήνα οι ασθενείς έλαβαν ασπιρίνη(100-325mg/day) και κλοπιδογρέλη 75mg/day. Η εκτίμηση της υποτροπής ισχαιμίας βασίστηκε σε στατικό και δυναμικό σπινθηρoγράφημα θαλλίου στους 3 και 6-8 μήνες μετά την PTCA. Αιμοδυναμικά, σε όσους υπέστησαν νέα στεφανιογραφία μέχρι και τους 6-8 μήνες, η επαναστένωση ορίσθηκε ως ≥ 50% στένωση του αυλού του αγγείου στο σημείο όπου έγινε η αγγειοπλαστική.
Εκτός από την ομάδα των ασθενών και μια ομάδα υγιών μαρτύρων 83 ατόμων, συμμετείχε στη μελέτη για σύγκριση της συχνότητας του γονότυπου. Το τελικό καταληκτικό σημείο για την παραπάνω μελέτη, ήταν η συχνότητα της υποτροπής ισχαιμίας στους 8 μήνες κλινικής παρακολούθησης.
Υποτροπή ισχαιμίας και της επαναστένωσης ≥ 50% σε όσους υπεβλήθησαν σε νέα στεφανιογραφία, συνέβη σε 15 από τους 96 ασθενείς. Ας σημειωθεί ότι οι περισσότεροι ασθενείς (70/96) είχαν το
φυσιολογικό γονότυπο με το αλληλόμορφο I, λιγότεροι ασθενείς
(23/96) είχαν το Insertion/Deletion και μόλις 3/96 είχαν το Deletion/ Deletion γονότυπο. Από το γονοτυπικό group, υποτροπή ισχαιμίας παρουσιάσθηκε σε 11/70 για τον I/I, 3/23 για τον I/D γονότυπο και 1/3 για τον D/D γονότυπο. Δε βρέθηκε συσχέτιση μεταξύ πολυμορφισμού γονιδίου και υποτροπής ισχαιμίας στους ασθενείς μετά από αγγειοπλαστική στεφανιαίων αρτηριών.
Προηγούμενες μελέτες έχουν ερευνήσει τη συσχέτιση των πολυμορφισμών των γονιδίων της ACE, του AT1 υποδοχέα της αγγειοτενσίνης II και της CETP με την επαναστένωση μετά από αγγειοπλαστική. Εντούτοις, καμιά μελέτη δεν πραγματοποιήθηκε που να συγκρίνει τον α2Β-AR πολυμορφισμό και την υποτροπή ισχαιμίας μετά από αγγειοπλαστική στεφανιαίων αρτηριών. Όπως αρχικά αναφέρθηκε, ο γονότυπος α2Β ευνοεί τη μετανάστευση των αγγειακών SMCs, επηρεάζει τη λειτουργία του Α.Ν.Σ. και συσχετίζει το α2Β-AR αλληλόμορφο D deletion με οξέα στεφανιαία επεισόδια. Όλα τα παραπάνω στοιχεία μπορεί να δικαιολογούν το ρόλο του α2Β-AR πολυμορφισμού στην υποτροπή ισχαιμίας και πιθανόν την επαναστένωση μετά από αγγειοπλαστική στεφανιαίων αρτηριών. Βέβαια, η αρνητική συσχέτιση των πολυμορφισμών του α2Β-AR και της CETP ΤaqIB με την υποτροπή ισχαιμίας μετά από αγγειοπλαστική, μπορεί να θεωρηθεί προκαταρκτική, δεδομένου ότι συμμετείχε σχετικά μικρός αριθμός ασθενών συγκριτικά με μεγάλες πληθυσμιακές μελέτες και επειδή ο D/D γονότυπος δεν είναι ιδιαίτερα συχνός(για τη μελέτη των α2Β-AR).
Όσον αφορά τη μελέτη με τη CETP, διερευνήσαμε τον πολυμορφισμό ΤaqIB που είναι μια σιωπηρή μετάλλαξη βάσης στο 277 νουκλεοτίδιο της CETP(η οποία μπορεί να αναγνωρισθεί με την περιοριστική ενδονουκλεάση ΤaqI), με την πιθανότητα υποτροπής ισχαιμίας μετά από αγγειοπλαστική στεφανιαίων αρτηριών. Οι όροι Β1 και Β2 αντίστοιχα χρησιμοποιήθηκαν για να δηλώσουν την ύπαρξη ή μη της
περιοριστικής περιοχής (site) της ΤaqIB. Το Β2 αλληλόμορφο
σχετίζεται με αυξημένα επίπεδα HDL και ελαττωμένα επίπεδα
CETP, τόσο σε υγιείς όσο και σε άτομα με στεφανιαία νόσο(μοιάζει με ήπιας μορφής ανεπάρκεια CETP). Αντίθετα το Β1 αλληλόμορφο σχετίζεται με ελαττωμένα επίπεδα HDL και με αυξημένα επίπεδα και δραστηριότητα CETP.
Επειδή η ΤaqIB σχετίζεται με χαμηλά επίπεδα HDL και αυξημένο κίνδυνο για CHD(επηρεάζοντας το μεταβολισμό των λιποπρωτεϊνών), μπορεί να συμμετέχει στην παθοφυσιολογία της υποτροπής ισχαιμίας μετά από αγγειοπλαστική.
Μελετήσαμε 204 ασθενείς από το έτος 2001 έως και το 2003 με την προοπτική να διερευνηθεί η συσχέτιση ΤaqIB στον Ελλαδικό πληθυσμό με την πιθανότητα υποτροπής ισχαιμίας μετά από αγγειοπλαστική σε άτομα που φέρουν τον παραπάνω γονότυπο. Η συχνότητα της ΤaqIB(54%) ήταν παρόμοια με τη συχνότητα του πολυμορφισμού σε μια ομάδα 35 υγιών μαρτύρων.
Το αποτέλεσμα από αυτή τη μελέτη δεν αποδεικνύει ότι ο ΤaqIB πολυμορφισμός στο γονίδιο της CETP είναι σημαντικός προγνωστικός παράγων για εκτίμηση του κινδύνου υποτροπής ισχαιμίας μετά από αγγειοπλαστική στεφανιαίων αρτηριών.
Συμπερασματικά, η υποτροπή ισχαιμίας μετά από αγγειοπλαστική στεφανιαίων αρτηριών οφείλεται σε έναν πολύπλοκο μηχανισμό και σε ένα πολυπαραγοντικό φαινόμενο.
Μπορεί οι πολυμορφισμοί του α2Β και της CETP, να μην αναδείχθηκαν ως ανεξάρτητοι παράγοντες υποτροπής ισχαιμίας μετά από αγγειοπλαστική στεφανιαίων αρτηριών, αλλά σε συνδυασμό με άλλους πολυμορφισμούς γονιδίων και υπό την επίδραση συγκεκριμένων περιβαλλοντικών παραγόντων, είναι πολύ πιθανόν να συμμετέχουν στην παραπάνω διεργασία της υποτροπής ισχαιμίας και κατ’επέκταση της επαναστένωσης μετά από PTCA. / Coronary heart disease is one of the most common causes of morbidity and mortality in the population. A great percent of the patients with coronary heart disease may undergo percutaneous coronary angioplasty (PTCA) with or without the implantation of stents, mainly when the stenosis of the vessel is ≥ 70-75%. Despite the progress made with the introduction of drug-eluting stents and the reduction of the restenosis rate up to 5%-10%, the Achillean heel of the angioplasty using bare metal stents, is the restenosis rate which is 20%-25% of all cases.
The use of drug-eluting stents is limited in cases with restenosis, in patients with diabetes mellitus and in high-risk for restenosis lesions. The great percent of late restenosis(≥ 9-10%) and the high price of drug-eluting stents, make more urgent the necessity for more intense research on the identification of the exact factors involved in the pathophysiology of restenosis.
The primary objective of our study is to define the role of gene polymorphisms in the recurrence of ischaemia after PTCA and the implantation of the stents.
Virtually, we scrutinely examined the role of the genetic polymorhisms of α2Badrenergic receptor and the CETP(Cholesteryl Ester Transfer Protein)-TaqIB polymorphism.
Our assumption was based on the conclusion drawn by a study conducted in Finnish patients, which showed that D/D genotype confers 2,5 increase in the risk for acute coronary events(including acute myocardial infarction). The intense vasoconstriction properties of the α2Badrenergic polymorphism both on the coronary arteries and the periphery is considered to be the primary cause of the acute coronary events.
The aforementioned statement with the significant role of α2B
adrenergic receptor α2B-AR on the hyperplasia and mainly the migration of smooth muscle cells, probably correlates well with the pathophysiology of the recurrence of ischaemia after PTCA.
We conducted a genetic association/prospective follow-up study in 96 Greek coronary artery disease patients undergoing coronary angioplasty and stent implantation. 81 patients were men and 15 women(mean age ± standard deviation=57,7± 10,1 years, ranges 37-76 years old) who presented with symptomatic CAD. All patients were enrolled in the study between 2001 and 2003 and were followed-up clinically for 6-8 months after an initially successful procedure. Post-angioplasty and for one (1) month following the procedure, all the patients received aspirin(100-325mg/day) and clopidogrel(75mg/day).
Assessment of recurrence of ischaemia was based on positive thallium stress testing(at least moderate defect to the distribution of the culprit lesion of the vessel which was revascularised). Hemodynamically, restenosis was defined as ≥50% narrowing of the vessel at the point where angioplasty was performed.
In addition to the patient group, a control group of totally 83 asymptomatic individuals were included in the study for comparison of the frequency of the genotype. The final end-point of the current study was the incidence of restenosis at 8 months of clinical follow-up.
Recurrence of ischaemia (including restenosis rate ≥50% to the patients who underwent coronary angiography) occurred in 15 of the 96 patients.
In note, the majotiy of patients (70/96) had the Insertion/Insertion genotype, fewer patients (23/96) had the Insertion/Deletion genotype and only 3/96 had the Deletion /Deletion genotype.
With regard to to the genotype groups , restenosis was found in 11/70 for I/I, 3/23 for I/D and 1/3 for the D/D genotype. No association between gene polymorphisms and recurrence of ischaemia was detected to the patients who underwent coronary angioplasty.
Previous studies have investigated the association between gene polymorhisms of angiotensin-converting enzyme(ACE), the AT1 receptor for angiotensin II and cholesteryl ester transfer protein (CETP) with restenosis in patients after coronary angioplasty.
However, no study has been performed to involve the α2B-AR polymorphism with recurrence of ischaemia after percutaneous angioplasty of coronary vessels.
As it was initially mentioned, α2B genotype promotes the migration of vascular SMCs, influences the function of autonomic nervous system and the α2B-AR deletion variant is associated with acute coronary events.
All these data might correlate the role of α2B-AR polymorphism with the recurrence of ischaemia and probably with the restenosis after an angioplasty of coronary vessels.
Nevertheless, the negative findings of our study might be considered preliminary, taking into account the small number of patients that were studied and the rarity of the Deletion/Deletion(D/D) genotype.
As far as the CETP study, we investigated the TaqIB polymorphism, which is a silent base change affecting the 277th nucleotide and can be identified by the restriction endonuclease TaqI, with the chance of recurrence of ischaemia after PTCA. The terms B1 and B2 are used to denote the presence and absence, respectively, of the TaqI restriction site. The B2 allele has been associated with increased HDL levels and decreased CETP levels and activity in both patients with CHD and healthy subjects(resembling a mild form of CETP deficiency).
On the other hand, the B1 allele has been associated with decreased HDL levels and increased CETP levels and activity.
Due to the fact that TaqIB is associated with decreased HDL levels
and increased risk for CHD, affecting the lipoprotein metabolism
might be involved in the pathophysiology of reccurence of ischaemia after PTCA.
We studied 204 patients between 2001 and 2003 with the primary objective to investigate the frequency of TaqIB and possible association with reccurence of ischaemia after PTCA in the patients who have this genotype. The frequency of TaqIB was 54% similar to the frequency of the polymorphism in a group of 35 healthy controls.
The results from this study does not indicate that the TaqIB polymorphism at the CETP gene locus is a significant predictor for assessing the risk of reccurence of ischaemia after PTCA.
As a conclusion, reccurence of ischaemia after PTCA is due to a complicated mechanism and to a multifactoral phenomenon. Virtually, we didn’t find any correlation of α2ΒAR polymorphism and CETP TaqIB with reccurence of ischaemia, especially as causitive factors, but based on their role in the pathophysiology, under certain circumstances, especially with the cooperation of other genes, these polymorphisms can not be definitely excluded in the reccurence of ischaemia and the restenosis after PTCA.
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Comparação entre a atividade da proteína de transferência de colesterol esterificado e o tamanho da HDL na associação com a aterosclerose carotídea / Comparison between cholesteryl ester transfer protein and HDL size in association with carotid atherosclerosisParra, Eliane Soler, 1981- 25 August 2018 (has links)
Orientadores: Andrei Carvalho Sposito, Eliana Cotta de Faria / Texto em português e inglês / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-25T06:33:21Z (GMT). No. of bitstreams: 1
Parra_ElianeSoler_D.pdf: 3645332 bytes, checksum: 085ab65e147faa7a1f1684591c22e6d8 (MD5)
Previous issue date: 2014 / Resumo: A lipoproteína de alta densidade (HDL) é um complexo heterogêneo e versátil de partículas com variações funcionais resultantes da integração de uma vasta gama de componentes, como apolipoproteínas, receptores, transportadores, enzimas e fosfolípides, com ações indiretas ou diretas sobre o seu metabolismo. Além disso, as concentrações plasmáticas do colesterol da HDL (HDL-C) e seu tamanho representam importantes fatores inversos ao desenvolvimento de doenças cardiovasculares, particularmente em indivíduos em prevenção primária. A proteína de transferência de colesterol esterificado (CETP) desempenha uma função importante no transporte reverso do colesterol (TRC) que é umas das principais funções antiaterogênicas da HDL. No entanto, a atividade da CETP é inversamente associada às concentrações de HDL-C e ao tamanho da partícula. Adicionalmente, HDL grande demonstra ser mais efetiva no efluxo do colesterol, parte integrante do TRC, comparada à partícula de HDL menor. Nesse contexto, o objetivo do estudo foi avaliar, em indivíduos livres de doença aterosclerótica manisfesta, a associação entre o tamanho da HDL e a redução da atividade da CETP induzida geneticamente com a carga aterosclerótica carotídea. Utilizamos para esse fim dois polimorfismos da CETP, TaqIB e I405V, que foram bem caracterizados funcionalmente e encontrados frequentemente na população. Assim, os objetivos desta tese foram: (i) investigar se a presença dos polimorfismos TaqIB e I405V do gene da CETP está associada às concentrações de HDL-C e à aterosclerose carotídea subclínica (n=207); (ii) pesquisar se, além das concentrações de HDL-C, o tamanho da partícula de HDL está associado à aterosclerose subclínica (n=284). Para estes estudos foram determinados os perfis lipídicos, lipoproteícos e apoproteícos, proteína C-reativa (PCR), anticorpos anti-LDL oxidada, atividades das proteínas CETP e de transferência de fosfolípides (PLTP), HDL2 e HDL3 e o diâmetro da HDL. Os polimorfismos TaqIB e I405V da CETP também foram detectados. A espessura da camada íntima-medial da artéria carótida comum (EIMc) foi mensurada por ultrassonografia. Na presença do menor alelo dos polimorfismos TaqIB e I405V da CETP, EIMc correlacionou-se inversamente com atividade da CETP e positivamente com atividade da PLTP e anticorpos anti-LDL oxidada. Na análise multivariada, a presença do menor alelo do polimorfismo TaqIB, mas não do I405V, foi associado a um aumento de 5,1 vezes de risco de maior EIMc. No entanto, a atividade da CETP não diferiu entre os grupos de presença e ausência do menor alelo do polimorfismo TaqIB. Com relação ao tamanho das partículas, HDL maiores foram associadas a menores EIMc e foram melhores indicadores de risco de aterosclerose carotídea subclínica comparadas às concentrações de HDL-C. Em conclusão, o aumento do tamanho da HDL tem associação independente com a carga aterosclerótica e, embora o polimorfismo TaqIB também se associe, sua interação parece ser independente da atividade da CETP / Abstract: High-density lipoproteins ( HDL ) are a group of heterogeneous and complex particles with versatile functional changes resulting from the integration of a wide range of components, such as apolipoproteins, receptors, transporters, enzymes and phospholipids with indirect or direct actions on your metabolism. In addition, plasma concentrations of HDL cholesterol (HDL -C) and its size are inversely related to the development of cardiovascular diseases, particularly in primary prevention in individuals. The cholesterol ester transfer protein (CETP) plays an important role in reverse cholesterol transport (RCT), which is one of the main functions of HDL. However, CETP activity is inversely related to HDL-C and particle size. Additionally, largest HDL particles have demonstrated a higher cholesterol efflux capacity. In this context, the aim of the study was to evaluate, in individuals free of manifest atherosclerotic disease, the association between the size of HDL and CETP activity genetically induced with carotid atherosclerosis burden. We used for this purpose, two polymorphisms of CETP TaqIB and I405V, which have been well characterized functionally and often found in the population. The objectives of this thesis were: (i) to investigate whether the presence of polymorphisms I405V and TaqIB of CETP gene is associated with HDL-C and subclinical carotid atherosclerosis (n= 207); (ii) to investigate if, in addition to HDL-C, the particle size of HDL is associated with atherosclerosis (n= 284). We determined lipid, lipoprotein profiles and apolipoprotein, C-reactive protein (CRP), antibodies against oxidized LDL, CETP and phospholipid transfer protein (PLTP) activities, HDL2 and HDL3 and HDL size. The TaqIB and I405V CETP polymorphisms were also analyzed. Common carotid artery intima-media thickness (cIMT) was measured using ultrasonography. In the presence of the minor alleles of the TaqIB and I405V polymorphisms of CETP, cIMT was inversely correlated with CETP activity and positively with PLTP activity and antibodies against oxidized LDL. In multivariate analysis, the presence of the minor allele of the TaqIB polymorphism, but not the I405V, was associated with a 5.1 times increased risk of higher cIMT. However, CETP activity did not differ between the presence and absence of minor allele groups of the TaqIB polymorphism. Regarding HDL size, increased HDL size was associated with lower cIMT and was better marker of risk of subclinical carotid atherosclerosis compared to HDL-C. In conclusion, increased size of HDL is independently associated with atherosclerotic and, although TaqIB polymorphism is also associated, its interaction seems to be independent of CETP activity / Doutorado / Clinica Medica / Doutora em Clínica Médica
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A proteína de transferência de colesterol esterificado humana protege camundongos da sepse polimicrobiana e atenua a resposta inflamatória em macrófagos estimulados com lipopolissacarídeo / The human cholesteryl ester transfer protein protects mice from polymicrobial sepsis and attenuates the inflammatory response in macrophages stimulated with lipopolysaccharideVenancio, Tatiana Martins 09 February 2015 (has links)
Sepse é a resposta inflamatória sistêmica decorrente de infecção grave, com alto índice de mortalidade, tornando-se um grave problema de saúde pública. Apesar dos inúmeros estudos realizados em busca de alternativas terapêuticas, o entendimento acerca dos mecanismos envolvidos na doença permanece restrito. A interação entre o metabolismo lipídico e a resposta inflamatória tem sido intensamente investigada. Neste estudo, avaliou-se a influência da proteína de transferência de colesterol esterificado (CETP) - glicoproteína plasmática que promove a transferência de lípides entre lipoproteínas - na resposta inflamatória. Inicialmente, foram comparados camundongos transgênicos para CETP humana (CETP) e controles irmãos não transgênicos (WT) submetidos ao modelo de sepse polimicrobiana de ligadura e perfuração do ceco (CLP), avaliando a taxa de sobrevida e o perfil inflamatório entre os grupos. Em seguida, a resposta inflamatória em macrófagos de peritônio de camundongos estimulados com LPS na ausência ou presença da CETP exógena (CETP humana recombinante) e endógena (macrófagos de animais CETP) foi analisada. Verificou-se que camundongos CETP apresentaram maior taxa de sobrevida, maior migração de linfócitos para o foco infeccioso, menores concentrações plasmáticas de IL-6 e menor expressão proteica do receptor Toll-like 4 (TLR4) e da enzima aciloxiacilo hidrolase (AOAH) no fígado, comparados aos WT. Nos macrófagos, observou-se que a presença da CETP recombinante foi capaz de se ligar ao LPS, pela análise da microscopia confocal, e, em cultura, reduziu de forma dose dependente a captação de LPS, a expressão de TLR4, a ativação do NF-kB (p65) e a secreção de IL-6 para o sobrenadante do cultivo celular. Os dados obtidos com os macrófagos de animais CETP corroboraram, em parte, os encontrados com a utilização da CETP exógena. Houve redução da captação de LPS e da ativação do NF-kB (p65), sem alteração na expressão de TLR4 e secreção de IL-6. Entretanto, apresentaram redução das concentrações de TNF-alfa celular e no sobrenadante de cultura. Dessa maneira, foi possível concluir que a CETP atua como agente modulador da resposta inflamatória induzida pela CLP e em macrófagos estimulados pelo LPS. Esses achados devem ser considerados nas doenças inflamatórias e nos futuros estudos relacionados à inibição da CETP, além de estabelecer novas perspectivas de tratamento da sepse / Sepsis is a systemic inflammatory response due to serious infection with high mortality rate, which has become a serious problem for public health. Despite numerous studies seeking for therapeutic alternatives, the understanding of the mechanisms involved in this disease remains limited. The interaction between lipid metabolism and inflammatory response has been intensively investigated. In the present study it was evaluated the influence of CETP (cholesteryl ester transfer protein) - plasma glycoprotein that promotes the transfer of lipids between lipoprotein - in the inflammatory response. Initially transgenic mice for human CETP (CETP) were compared to non transgenic control mice (WT) after polymicrobial sepsis induced by cecal ligation and puncture (CLP), to determine survival rate and the inflammatory profile between groups. Then, macrophages isolated from peritoneal cavity stimulated with LPS in the presence or absence of exogenous CETP (recombinant human CETP) and endogenous CETP (macrophages from CETP mice) were analyzed. It was found that CETP mice showed a higher survival rate, a greater lymphocyte migration to infectious focus, a lower IL-6 plasma concentration and a decrease in Toll-like receptor 4 (TLR4) and acyloxyacyl hydrolase enzyme (AOAH) protein expression in the liver in comparison to WT mice. In macrophages, recombinant CETP was able to bind to LPS, by confocal microscopy analysis and in cell culture, it was observed that in the presence of the recombinant CETP macrophages presented decreased in LPS uptake, TLR4 expression, NF-kB activation (p65) and IL-6 secretion into the cell culture medium. Furthermore, the results with macrophages from animals CETP corroborate partly with what was found in the exogenous experiments. LPS uptake and NF-kB activation (p65) were reduced, but no difference regarding the expression of TLR4, nor the IL-6 secretion to the cell culture medium. However, the CETP group also showed reduced levels of TNF-alfa both in macrophages and in the culture supernatant. Thus, we conclude that CETP acts as modulator of the inflammatory response induced by CLP and in the macrophages stimulated by LPS. In addition, new therapeutic perspectives could be established
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A proteína de transferência de colesterol esterificado humana protege camundongos da sepse polimicrobiana e atenua a resposta inflamatória em macrófagos estimulados com lipopolissacarídeo / The human cholesteryl ester transfer protein protects mice from polymicrobial sepsis and attenuates the inflammatory response in macrophages stimulated with lipopolysaccharideTatiana Martins Venancio 09 February 2015 (has links)
Sepse é a resposta inflamatória sistêmica decorrente de infecção grave, com alto índice de mortalidade, tornando-se um grave problema de saúde pública. Apesar dos inúmeros estudos realizados em busca de alternativas terapêuticas, o entendimento acerca dos mecanismos envolvidos na doença permanece restrito. A interação entre o metabolismo lipídico e a resposta inflamatória tem sido intensamente investigada. Neste estudo, avaliou-se a influência da proteína de transferência de colesterol esterificado (CETP) - glicoproteína plasmática que promove a transferência de lípides entre lipoproteínas - na resposta inflamatória. Inicialmente, foram comparados camundongos transgênicos para CETP humana (CETP) e controles irmãos não transgênicos (WT) submetidos ao modelo de sepse polimicrobiana de ligadura e perfuração do ceco (CLP), avaliando a taxa de sobrevida e o perfil inflamatório entre os grupos. Em seguida, a resposta inflamatória em macrófagos de peritônio de camundongos estimulados com LPS na ausência ou presença da CETP exógena (CETP humana recombinante) e endógena (macrófagos de animais CETP) foi analisada. Verificou-se que camundongos CETP apresentaram maior taxa de sobrevida, maior migração de linfócitos para o foco infeccioso, menores concentrações plasmáticas de IL-6 e menor expressão proteica do receptor Toll-like 4 (TLR4) e da enzima aciloxiacilo hidrolase (AOAH) no fígado, comparados aos WT. Nos macrófagos, observou-se que a presença da CETP recombinante foi capaz de se ligar ao LPS, pela análise da microscopia confocal, e, em cultura, reduziu de forma dose dependente a captação de LPS, a expressão de TLR4, a ativação do NF-kB (p65) e a secreção de IL-6 para o sobrenadante do cultivo celular. Os dados obtidos com os macrófagos de animais CETP corroboraram, em parte, os encontrados com a utilização da CETP exógena. Houve redução da captação de LPS e da ativação do NF-kB (p65), sem alteração na expressão de TLR4 e secreção de IL-6. Entretanto, apresentaram redução das concentrações de TNF-alfa celular e no sobrenadante de cultura. Dessa maneira, foi possível concluir que a CETP atua como agente modulador da resposta inflamatória induzida pela CLP e em macrófagos estimulados pelo LPS. Esses achados devem ser considerados nas doenças inflamatórias e nos futuros estudos relacionados à inibição da CETP, além de estabelecer novas perspectivas de tratamento da sepse / Sepsis is a systemic inflammatory response due to serious infection with high mortality rate, which has become a serious problem for public health. Despite numerous studies seeking for therapeutic alternatives, the understanding of the mechanisms involved in this disease remains limited. The interaction between lipid metabolism and inflammatory response has been intensively investigated. In the present study it was evaluated the influence of CETP (cholesteryl ester transfer protein) - plasma glycoprotein that promotes the transfer of lipids between lipoprotein - in the inflammatory response. Initially transgenic mice for human CETP (CETP) were compared to non transgenic control mice (WT) after polymicrobial sepsis induced by cecal ligation and puncture (CLP), to determine survival rate and the inflammatory profile between groups. Then, macrophages isolated from peritoneal cavity stimulated with LPS in the presence or absence of exogenous CETP (recombinant human CETP) and endogenous CETP (macrophages from CETP mice) were analyzed. It was found that CETP mice showed a higher survival rate, a greater lymphocyte migration to infectious focus, a lower IL-6 plasma concentration and a decrease in Toll-like receptor 4 (TLR4) and acyloxyacyl hydrolase enzyme (AOAH) protein expression in the liver in comparison to WT mice. In macrophages, recombinant CETP was able to bind to LPS, by confocal microscopy analysis and in cell culture, it was observed that in the presence of the recombinant CETP macrophages presented decreased in LPS uptake, TLR4 expression, NF-kB activation (p65) and IL-6 secretion into the cell culture medium. Furthermore, the results with macrophages from animals CETP corroborate partly with what was found in the exogenous experiments. LPS uptake and NF-kB activation (p65) were reduced, but no difference regarding the expression of TLR4, nor the IL-6 secretion to the cell culture medium. However, the CETP group also showed reduced levels of TNF-alfa both in macrophages and in the culture supernatant. Thus, we conclude that CETP acts as modulator of the inflammatory response induced by CLP and in the macrophages stimulated by LPS. In addition, new therapeutic perspectives could be established
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