The analysis of reverse cholesterol system in apolipoprotein A-1 deficiency

载脂蛋白A-1缺乏症的逆胆固醇系统分析

• 批准号: 13672414
• 负责人: TSUKAMOTO Kazuhisa
• 金额: $ 2.3万
• 依托单位: The University of Tokyo
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2001
• 资助国家: 日本
• 起止时间: 2001 至 2002
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-13672414/
• 关键词: Apolipoprotein A-1; HDL; reverse cholesterol transport; anti-oxidation; paraoxonase; atherosclerosis; Apolipoprotein E; oxidation stress; コレステロール逆転送; パラオキソナーゼ; パラオキソネース; アポリポタンパクA1欠損症

We experienced a 69-year-old Japanese woman with severely reduced levels of plasma HDL-cholesterol level (5 mg/dl), caused by apolipoprotein (apo) A-I deficiency. She was not symptomatic for coronary heart disease (CHD) despite the accumulated risks for CHD. Therefore, we analyzed not only the genomic DNA sequence, but also the characters of her lipid profile and the HDL-associated enzymes that are supposed to exert anti-atherogenic properties.The genomic DNA sequencing of apoA-I identified a cytosine deletion at the third base of codon 184 in the fourth exon, which theoretically led to a frame shift mutation and an early termination at codon 200. However, Western blot analysis did not reveal not only a normal apoA-I protein but also a mutant apoA-I protein. The HDL particles were rich in apoE, and the size of HDL particles rich in apoE was large, suggesting that these HDLs would facilitate cholesterol efflux.The activity of LCAT was only slightly reduced compared with normal controls despite no apoA-I in the plasma, and the protein levels of CETP was in normal ranges despite that this enzyme is proposed to be associated with HDL. Paraoxonase 1 (PON1) is an enzyme that is associated with HDL and exerts an anti-atherogenic property. It has been proposed that PON1 is stabilized with apoA-I on HDL, however, the PON1 protein distributed exclusively on HDL in our patient, while its stability in both the activity and localization on HDL was reduced. This instability in localization of PON1 protein on HDL might facilitate the delivery of PON1 protein to peripheral tissues through HDL particles, probably contributing to the protection from CHD in this patient.

我们经历了一个69岁的日本女性严重降低血浆高密度脂蛋白胆固醇水平（5毫克/分升），引起载脂蛋白（apo）A-I缺乏。她没有冠心病（CHD）的症状，尽管CHD的累积风险。因此，我们不仅分析了基因组DNA序列，而且还分析了她的血脂谱和HDL相关酶的特征，这些酶被认为具有抗动脉粥样硬化的特性。apoA-I基因组DNA测序确定了第四外显子密码子184的第三个碱基的胞嘧啶缺失，理论上导致了密码子200的移码突变和提前终止。然而，Western印迹分析不仅没有显示正常的apoA-I蛋白，而且也没有显示突变的apoA-I蛋白。HDL颗粒富含apoE，且颗粒较大，有利于胆固醇流出，血浆中无apoA-I时，LCAT活性仅略低于正常对照组，而CETP蛋白水平在正常范围内，尽管该酶被认为与HDL相关。对氧磷酶1（PON 1）是一种与HDL相关的酶，具有抗动脉粥样硬化的特性。已经提出PON 1与HDL上的apoA-I稳定，然而，PON 1蛋白在我们的患者中仅分布在HDL上，而其在HDL上的活性和定位的稳定性均降低。PON 1蛋白在HDL上定位的不稳定性可能促进PON 1蛋白通过HDL颗粒向外周组织的递送，可能有助于该患者对CHD的保护。

项目成果

Noto H., Hashimoto Y., Tsukamoto K.et al.: "Exclusive Association of Paraoxonase 1 with HDL Particles in Apolipoprotein A-I Deficiency"Biochemical & Biophysical Research Communications. 289. 395-401 (2001)

Noto H.、Hashimoto Y.、Tsukamoto K.等人：“载脂蛋白 A-I 缺乏症中对氧磷酶 1 与 HDL 颗粒的专属关联”生物化学

Yokota H. Hashimoto Y. Okubo S. Yumoto M. Mashige F. Kawamura M. Kotani K. Usuki Y. Shimada S, Kitamura K. Nakahara K.: "Apolipoprotein A-I deficiency with accumulated risk for CHD but no symptoms ; of CHD"Atherosclerosis. 162. 399-407 (2002)

Yokota H. Hashimoto Y. Okubo S. Yumoto M. Mashige F. Kawamura M. Kotani K. Usuki Y. Shimada S, Kitamura K. Nakahara K.：“载脂蛋白 A-I 缺乏会累积患 CHD 的风险，但没有症状；CHD”

Yokota H., Hashimoto Y., Yumoto M., Nakahara K.et al.: "Apolipoprotein A-I deficiency with accumulated risk for CUD but no symptoms of CHD"Atherosclerosis. 162. 399-407 (2002)

Yokota H.、Hashimoto Y.、Yumoto M.、Nakahara K.等人：“载脂蛋白 A-I 缺乏会累积 CUD 风险，但没有 CHD 症状”动脉粥样硬化。

Hiroshi Noto: "Exclusive association of paraoxonase 1 with HDL particles in apoA1 deficiency"Biochem Biophys Res Commun. 289. 395-401 (2001)

Hiroshi Noto：“apoA1 缺乏症中对氧磷酶 1 与 HDL 颗粒的独家关联”Biochem Biophys Res Commun。

Yokota H., Hashimoto Y., Yumoto M., Nakahara K.et al.: "Apolipoprotein A-I deficiency with accumulated risk for CHD but no symptoms of CHD"Atherosclerosis. 162. 399-407 (2002)

Yokota H.、Hashimoto Y.、Yumoto M.、Nakahara K.等人：“载脂蛋白 A-I 缺乏会累积患 CHD 的风险，但没有 CHD 症状”动脉粥样硬化。