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京都大学 / 新制・課程博士 / 博士(医学) / 甲第23802号 / 医博第4848号 / 新制||医||1058(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 永井 洋士, 教授 羽賀 博典, 教授 木村 剛 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

Individer med homozygot familjär hyperkolesterolemi(FH), har höga halter av Low Density Lipoprotein (LDL) vilket leder till ökad risk för kardiovaskulära sjukdomar. Behandling av dessa individer kan göras med extrakorporal elimination av LDL med hjälp av specifika reningskolonner. Syftet med studien var att utvärdera några agarosmodifierade adsorbenter för denna applikation. Adsorbenterna, modifierad polyakrylat (DALI), agaros (Zetaros), direkt sulfateradZetarose och taurin immobiliserad Zetarose, inkuberades med humant plasma spädd med PBS, och en volyms förhållande mellan matris och plasman på 1:5. Inkubering utfördes i rumstemperatur under 60 min med kontinuerlig blandning i rotator. Efter inkubation centrifugerades proverna och LDL bestämdes i såväl supernatant som pellet. Totalmängd adsorberade proteiner analyserades också i eluat från erhållen pellet. LDL bestämdes indirekt med hjälp av Friedewaldsformel (LDL = totalkolesterol (TC) –highdensitylipoprotein (HDL) - (0,45 x Triglycerider(TG)). TC och TG bestämdes enzymatiskt medan HDL kvantifierades som TC efter utfällning av LDL med dextransulfat. Resultaten visar tydligt att DALI har god adsorptionsförmåga.Dock uppvisar de modifierade Zetaroserna begränsad adsorptionskapacitet för LDL. Vid desorption av adsorbenterna visar SDS en bättre elueringsförmåga än NaCl relaterad till protein, vilket tyder hydrofoba proteiner. Metodiken som används i studien är lämplig för vidare studier av andra adsorbenter som förväntas användas i kliniska applikationer för elimination av LDL hos FH patienter. / Individuals that suffer from homozygote Familiar Hyperkolesterolemia (FH), has increased amounts of Low Density Lipoproteins (LDL) which leads to a higher risk of cardiovascular diseases. Treatment of these individuals can be achieved by extracorporeal elimination of LDL using specific columns. The aim of this study was to evaluate different agarose-modified adsorbents ability to adsorb LDL from human plasma. The adsorbents (DALI, Zetarose, sulphonated Zetarose and taurine immobilized onto Zetarose) were incubated for 60 minutes with human plasma diluted with PBS, in a ratio of 1:5 between the matrix and the plasma during rotation with a rotator. After incubation the samples were centrifuged and the LDL content was determined in both the supernatant and the pellet. The amount proteins adsorbed were assayed by eluting the pellets. LDL was determined indirectly using Friedwalds equation; LDL= Total cholesterol (TC) - High density lipoprotein (HDL)-(0,45x Triglycerides (TG). The values of TC and TG in the sample were determined enzymatically, whilst HDL was quantified as TC after LDL-precipitation by dextran sulfate. The results clearly show that DALI has good adsorption capacity, but none of the modified Zetaroses shows any capacity to absorb LDL from human plasma. Desorption of the adsorbents using SDS gave higher amounts of eluated protein compared to NaCl elution, indicating hydrofobic proteins. However, the methods used in this study could be used to evaluate new adsorbents for LDL-elimination applications in patients with chronic hyperlipemia.

L’hyperchylomicronémie familiale est un trait monogénique caractérisé par un taux de triglycérides plasmatiques à jeun supérieur à 10 mmol/L (la normale étant de 1,7 mmol/L). L’hyperchylomicronémie familiale est le plus souvent causée par une déficience dans le gène LPL (pour lipoprotéine lipase). La déficience en lipoprotéine lipase (LPLD) est aussi associée à un risque élevé de pancréatite. La pancréatite en soi est reconnue comme un trait complexe génétique dont plusieurs gènes sont associés à sa susceptibilité. Étant donné l’expression variable de la pancréatite chez les patients LPLD, les résultats de ce mémoire présentent certains facteurs génétiques pouvant être responsables du risque de l’expression de la pancréatite aigüe récurrente chez les sujets LPLD. L’analyse par séquençage des régions codantes et promotrices des gènes CTRC (pour « Chymotrypsin C ») et SPINK1 (pour « Serine protease inhibitor Kazal type 1 ») a été effectuée chez 38 patients LPLD et 100 témoins. Ces deux gènes codent pour des protéines impliquées dans le métabolisme des protéases au niveau du pancréas et ont déjà été associés avec la pancréatite dans la littérature. Notre étude a permis d’identifier une combinaison de deux polymorphismes (CTRC-rs545634 et SPINK1-rs11319) associée significativement avec la récidive d’hospitalisations pour douleur abdominale sévère ou pour pancréatite aigüe récurrente chez les patients LPLD (p<0,001). Ces résultats suggèrent que le risque de récidive de pancréatite chez les patients LPLD peut être influencé par des variants dans des gènes de susceptibilité à la pancréatite. L’identification de biomarqueurs génétiques améliore la compréhension des mécanismes physiopathologiques de la pancréatite chez les patients LPLD ce qui, par conséquent, permet de mieux évaluer et caractériser les risques de pancréatite afin d'adapter un plan d'intervention préventif pour ces patients. / Familial hyperchylomicronemia is a monogenic trait characterized by an increased fasting plasma triglyceride levels ≥ 10 mmol/L (normal is 1.7 mmol/L). Familial hyperchylomicronemia is most often caused by a deficiency in the LPL gene. Lipoprotein lipase deficiency (LPLD) is also associated with an increased risk of pancreatitis. Pancreatitis is recognized as a complex genetic trait and several genes are associated with its susceptibility. Considering the variable expression of pancreatitis in LPLD patients, results of this manuscript demonstrate that genetic factors may be responsible of the increased risk of recurrent acute pancreatitis episodes in LPLD subjects. The sequencing analysis of the coding and promoters regions of CTRC gene (for Chymotrypsin C) and SPINK1 gene (for Serine protease inhibitor Kazal type 1) was performed. These two genes encode proteins involved in the metabolism of the pancreas proteases and have been associated with pancreatitis in literature. A combination of two polymorphisms (CTRC-rs545634 and SPINK1-rs11319) have been identified and associated with recurrent hospitalizations for severe abdominal pain or recurrent acute pancreatitis in LPLD patients (p <0.001). These results suggest that the risk of recurrent episodes of pancreatitis in LPLD patients may be influenced by variants in susceptibility genes. The identification of genetic biomarkers improves the understanding of the pathophysiological mechanisms of pancreatitis in LPLD patients which therefore helps to assess and characterize the risk of pancreatitis to adapt preventive intervention plan for these patients.

Introdução: estudos recentes demonstram que o aumento do colesterol na lipoproteína de alta densidade (HDL-C), induzido por medicamentos ou mutações genéticas, não é associado à redução de eventos coronarianos. A lipoproteína de alta densidade (HDL) apresenta aspectos funcionais distintos em relação ao seu papel cardioprotetor. Objetivo: desenvolver um escore de funcionalidade da HDL (EFH) e avaliar a sua associação com algoritmos de predição de risco cardiovascular e aterosclerose subclínica em indivíduos brasileiros. Metodologia: trata-se de um estudo transversal composto por duas etapas. Na 1ª etapa, o EFH preditor de risco cardiovascular (EFH-RCV) foi desenvolvimento e validado a partir de uma subamostra do estudo CARDIONUTRI (n=354). Na 2ª etapa, o EFH preditor de aterosclerose subclínica (EFH-AS) foi desenvolvido e validado com dados de uma subamostra do estudo ELSA-Brasil (n=4549). No estudo CARDIONUTRI foram avaliadas a atividade da paraoxonase 1 (PON1) e da proteína de transferência de ésteres de colesterol (CETP), a concentração da apolipoproteína AI (APOAI), a capacidade antioxidante da HDL (lag time) e as subfrações da HDL pelo método Lipoprint®. O estudo ELSA-Brasil avaliou as subfrações da HDL pelo método Vertical Auto Profile (VAP) e Ressonância Magnética Nuclear (RMN), e a aterosclerose subclínica por tomografia computadorizada, quantificação da calcificação da artéria coronária (CAC) e calculo do escore da CAC. Resultados: no desenvolvimento do EFH-RCV, a HDL grande apresentou maior força de associação com o risco cardiovascular no modelo múltiplo final (OR = 0,797; p <0,001). O EFH-RCV demonstrou bom desempenho em relação ao escore de risco de Framingham (AUC = 0,899; p <0,001), escore de risco de Reynolds (AUC = 0,722; p <0,001) e Adult Treatment Panel III/2013 (AUC = 0,864; p <0,001). Além disso, apresentou boa reprodutibilidade e correlação com aterosclerose subclínica, quando testado na amostra do estudo ELSA-Brasil, utilizando medidas da HDL grande derivadas do método VAP (AUC = 0,864; p <0,001 e r = 0,252 p <0,001) ou do método de RMN (AUC = 0,876; p <0,001 e r = 0,277; p <0,001). O EFH-AS foi desenvolvido a partir do tamanho da HDL (nm), que apresentou a associação mais forte com aterosclerose subclínica no modelo múltiplo final (OR = 0,549; p <0,001) e demonstrou bom desempenho (AUC = 0,769; p <0,001). Conclusão: o EFH apresentou associações mais fortes com o risco cardiovascular e a aterosclerose subclínica, independente do HDL-C, com destaque para a HDL grande. Os resultados controversos entre as subfrações da HDL e o risco cardiovascular parecem manter relação com as metodologias distintas utilizadas nas análises. Portanto, a validação dos métodos e a inclusão do tamanho da HDL como marcador de risco cardiovascular revela um futuro promissor como adjuvante na estimativa do risco cardiovascular, manejo de medicamentos e tomada de decisões na prática clínica. / Introduction: current studies have not presented association between high density-lipoprotein cholesterol (HDL-C) increase, induced by drugs or genetic mutations, and coronary events reduction. HDL plays different functional cardioprotective role. Objective: to develop a HDL functionality score (HFS) and to assessment its association with predictive cardiovascular risk algorithms and subclinical atherosclerosis outcomes in Brazilian subjects. Methods: cross-sectional study based in two steps. In the first step, the HFS predictor of cardiovascular risk disease (HFS-CVR) was developed and validated on CARDIONUTRI study subsample (n=354). In second step the HFS predictor of subclinical atherosclerosis (HFS-SA) was developed and validated on ELSA-Brasil study subsample (n=4549). CARDIONUTRI study evaluated paraoxonase 1(PON1) and cholesterol ester transfer protein (CETP) activity, apolipoprotein AI (APOAI) concentration, HDL antioxidant capacity, and HDL subfractions by standard Lipoprint® method. ELSA-Brasil study evaluated the size of HDL and subfractions by Vertical Auto Profile (VAP) and Nuclear Magnetic Resonance (NMR) method, and the diagnosis of subclinical atherosclerosis by computed tomography, quantifying coronary artery calcification (CAC) and CAC score. Results: in the development of HFS-CVR, the large HDL presented greater strength of association with cardiovascular risk in the multiple final model (OR = 0.797; p <0.001). The HFS-CVR showed satisfactory performance by Framingham risk score (AUC = 0.899; p <0.001), Reynolds risk score (AUC = 0.722; p <0.001) and Adult Treatment Panel III/2013 guidelines (AUC = 0.864; p <0.001). In addition, HFS-CVR presented satisfactory reproducibility and was associated with subclinical atherosclerosis on ELSA-Brasil sample using large HDL measurements derived from the VAP method (AUC = 0.864; p <0.001 and r = 0,252; p <0,001) or the NMR method (AUC = 0.876; p <0.001 and r = 0.277; p <0,001). HFS-AS was developed from the HDL size (nm), because presented greater association with subclinical atherosclerosis in the final multiple model (OR = 0.549; p <0.001). HFS-AS demonstrated satisfactory performance (AUC = 0.769; p <0.001). Conclusion: the HFS demonstrates strong association with cardiovascular risk and subclinical atherosclerosis, independent of HDL-C, with emphasis on large HDL. Controversial results, between HDL subfractions and cardiovascular irsk seem to maintain a relation with the different methodologies used in analysis. Therefore, the validation of the methods and the inclusion of the HDL size as a cardiovascular risk marker reveal a promising future as an adjunct in the estimation of cardiovascular risk, drug management and decision making in clinical practice.

Sieben fibrogene und fünf nicht fibrogene (inerte) Mineralstäube wurden auf ihr Adsorptionsvermögen gegenüber Lipoproteinen untersucht. Die Adsorption erfolgte aus menschlichem Serum bzw. bovinem Lipoproteinkonzentrat. Die spezifischen Oberflächen der Stäube wurden mit Hilfe einer neuen Methode ermittelt, die auf der Adsorption von Nonadecansäure beruht. Sie vernachlässigt Oberflächenporen mit Öffnungsdurchmessern / Seven fibrogenic and five nonfibogenic (inert) mineral dusts were examined for their adsorption capacity for lipoproteins. Lipoproteins came from human serum and bovine lipoprotein- concentrate. The specific surface areas of the dusts were determined with the help of a new method, which is based on the adsorption of nonadecanoic acid. It neglects surface pores with opening diameters less than 2,5nm. The most important result is that fibrogenic dusts adsorb significantly more high density lipoproteins (HDL), than the inert dusts. The adsorption of HDL on quartz can be reduced up to 96% by addition of Polyvinylpyridine-N-oxide (PVPNO), an inhibitor of quartz- induced fibrosis. The HDL- adsorption might play a role during the developing process of mineral-dust-induced fibrosis.