New therapeutic targets for atherosclerotic plaques - The role of acyl CoA : cholesterol acyltransferase and neutral cholesterol ester hydrolase in foam cell formation

动脉粥样硬化斑块的新治疗靶点 - 酰基辅酶A的作用：胆固醇酰基转移酶和中性胆固醇酯水解酶在泡沫细胞形成中的作用

• 批准号: 12557092
• 负责人: ISHIBASHI Shun
• 金额: $ 8.51万
• 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 (B)
• 财政年份: 2000
• 资助国家: 日本
• 起止时间: 2000 至 2001
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-12557092/
• 关键词: atherosclerosis; gene targeting; adenovirus; ACAT; hormone-sensitive lipase; 泡沫細胞; マクロファージ; 遺伝子治療; アデノウイルス; コレステロール; コレステロールエステル

Cholesterol-ester (CE)-laden foam cells are a hallmark of atherosclerosis. Cholesterol is in a dynamic equilibrium between free and esterified form. The esterification and hydrolysis are mediated by acyl CoA : cholesterol acyltransferase (ACAT) and neutral cholesterol ester hydrolase (NCEH), respectively. In the current study, we investigated the role of ACAT-1, an ACAT isoform, and hormone-sensitive lipase (HSL) responsible for NCEH in foam cell formation and atherogenesis.We have generated ACAT-1 null (ACAT-1-/-) mice, which had decreased openings of the eyes because of atrophy of the meibomian glands, a modified form of sebaceous glands normally expressing high ACAT activities. To determine the role of ACAT-1 in atherogenesis, we crossed the ACAT-1-/- mice with mice lacking apolipoprotein (apo) E or the low density lipoprotein receptor (LDLR), hyperlipidemic models susceptible to atherosclerosis. High fat feeding resulted in extensive cutaneous xanthomatosis with loss of hair in both ACAT-1/-:apoE-/- and ACAT-1-/-:LDLR-/- mice. Free cholesterol content was significantly increased in their skin. Aortic fatty streak lesion size as well as cholesterol ester content were moderately reduced in both mutant mice compared with their respective controls. These results indicate that the local inhibition of ACAT activity in tissue macrophages is protective against cholesteryl ester accumulation but causes cutaneous xanthomatosis in mice lacking apo E or LDLR. Furthermore, we generated HSL-null (HSL-/-) mice, whose macrophages had a substantial activity of NCEH compared with those of wild-type. Consistently, lack of HSL did not aggravate the accumulation of CE in macrophages. Thus, it is rational that HSL is not the primary enzyme for NCEH in macrophages. However, adenoviral mediated overexpression of HSL markedly reduced the CE accumulation through accelerated hydrolysis of CE and decreased uptake of modified lipoproteins.

充满胆固醇酯（CE）的泡沫细胞是动脉粥样硬化的标志。胆固醇处于游离形式和酯化形式之间的动态平衡。酯化和水解分别由酰基CoA：胆固醇酰基转移酶(ACAT)和中性胆固醇酯水解酶(NCEH)介导。在当前的研究中，我们研究了 ACAT-1（一种 ACAT 亚型）和负责 NCEH 的激素敏感性脂肪酶 (HSL) 在泡沫细胞形成和动脉粥样硬化形成中的作用。我们生成了 ACAT-1 null (ACAT-1-/- ）小鼠，由于睑板腺萎缩而导致眼睛张开度降低，睑板腺是皮脂腺的一种改良形式，通常表达高 ACAT 活性。为了确定 ACAT-1 在动脉粥样硬化形成中的作用，我们将 ACAT-1-/- 小鼠与缺乏载脂蛋白 (apo) E 或低密度脂蛋白受体 (LDLR) 的小鼠（易患动脉粥样硬化的高脂血症模型）进行杂交。高脂肪喂养导致 ACAT-1/-:apoE-/- 和 ACAT-1-/-:LDLR-/- 小鼠出现广泛的皮肤黄瘤病并伴有毛发脱落。他们皮肤中的游离胆固醇含量显着增加。与各自的对照组相比，两种突变小鼠的主动脉脂肪条纹病变大小以及胆固醇酯含量均适度减少。这些结果表明，局部抑制组织巨噬细胞中的 ACAT 活性可防止胆固醇酯积累，但会导致缺乏 apo E 或 LDLR 的小鼠出现皮肤黄瘤病。此外，我们还生成了 HSL 缺失 (HSL-/-) 小鼠，与野生型相比，其巨噬细胞具有显着的 NCEH 活性。一致地，缺乏 HSL 并不会加剧巨噬细胞中 CE 的积累。因此，HSL 不是巨噬细胞中 NCEH 的主要酶是合理的。然而，腺病毒介导的 HSL 过度表达通过加速 CE 水解和减少修饰脂蛋白的摄取而显着减少 CE 积累。

项目成果

Tozawa R, Ishibashi S, Osuga J, Yamamoto K, Yagyu H, Ohashi K, Tamura Y, Yahagi N, Iizuka Y, Okazaki H, Harada K, Gotoda T, Shimano H, Kimura S, Nagai R, Yamada N: "Asialoglycoprotein receptor deficiency in mice lacking the major receptor subunit. Its obl

Tozawa R、Ishibashi S、Osuga J、Yamamoto K、Yagyu H、Ohashi K、Tamura Y、Yahagi N、Iizuka Y、Okazaki H、Harada K、Gotoda T、Shimano H、Kimura S、Nagai R、Yamada N：“亚洲糖蛋白

Chen Z,Ishibashi S, et al.: "Troglitazone Inhibits Atherosclerosis in Apolipoprotein E-Knockout Mice : Pleiotropic Effects on CD36 Expression and HDL."Arterioscler Thromb Vasc Biol.. 21(3). 372-377 (2001)

Chen Z，Ishibashi S 等人：“曲格列酮抑制载脂蛋白 E 敲除小鼠中的动脉粥样硬化：对 CD36 表达和 HDL 的多效性作用。”Arterioscler Thromb Vasc Biol.. 21(3)。

"Absence of ACAT-1 attenuates atherosclerosis but causesdry eye and cutaneous xanthomatosis in mice with congenital hyperlipidemia."J Biol Chem.. 275(28). 21324-30 (2000)

“ACAT-1 的缺失会减轻动脉粥样硬化，但会导致先天性高脂血症小鼠出现干眼症和皮肤黄瘤病。”J Biol Chem.. 275(28)。

Osuga J, Ishibashi S, Oka T, Yagyu H, Tozawa R, Fujimoto A, Shionoiri F, Yahagi N, Kraemer F B, Tsutsumi O, Yamada N: "Targeted disruption of hormone-sensitive lipase results in male sterility and adipocyte hypertrophy, but not in obesity"Proc Natl Acad S

Osuga J、Ishibashi S、Oka T、Yagyu H、Tozawa R、Fujimoto A、Shionoiri F、Yahagi N、Kraemer F B、Ttsutsumi O、Yamada N：“激素敏感性脂肪酶的靶向破坏会导致雄性不育和脂肪细胞肥大，但

Osuga J: "Targeted disruption of hormone-sensitive lipase results in male sterility and adipocyte hypertrophy, but not in obesity"Proc Natl Acad Sci USA. 97. 787-792 (2000)

Osuga J：“激素敏感性脂肪酶的靶向破坏会导致雄性不育和脂肪细胞肥大，但不会导致肥胖”Proc Natl Acad Sci USA。