Bonello-Palot Nathalie, Simoncini Stéphanie, Robert Stéphane, Bourgeois Patrice, Sabatier Florence, Levy Nicolas, Dignat-George Françoise, Badens Catherine
APHM, CHU de la Timone, Laboratoire de Génétique Moléculaire, Marseille, France; Aix-Marseille Université, Inserm UMR_S U910, Faculté de Médecine, Marseille, France.
Aix-Marseille Université, Inserm, VRCM, UMR_S 1076,13005, Marseille, France.
Atherosclerosis. 2014 Nov;237(1):45-52. doi: 10.1016/j.atherosclerosis.2014.08.036. Epub 2014 Aug 28.
Defects in lamin A maturation result in premature aging syndromes and severe atherosclerosis as observed in the Hutchinson-Gilford Progeria Syndrome. In age-related atherosclerosis, several features of cellular senescence have been characterized in endothelial cells including telomere shortening and increased oxidative stress. However, to date, very little is known about lamin A alterations in these cells.
To study lamin A-related senescence and its consequences in the activation status of primary endothelial cells.
Healthy primary endothelial cells and progenitors issued from human umbilical vein or cord blood were used. Lamin A defects were induced by protease inhibitor (Atazanavir) treatment for 48 h.
We show that protease inhibitor treatment leads to the accumulation of farnesylated prelamin A, inducing nuclear shape abnormalities and premature senescence in both differentiated and progenitor endothelial cells. ICAM-1-dependent activation and monocytes adhesion was increased in mature endothelial cells. In parallel, the ability to generate microvascular networks in matrigel was decreased for endothelial progenitors. The effects of protease inhibitor treatment on nuclear shapes were reversed when cells were treated in combination with Pravastatin and Zoledronate in both mature and progenitor endothelial cells. Reversion was also demonstrated with a morpholino antisense-oligonucleotide targeting lamin A-specific splice site.
This study shows that protease inhibitor treatment reproduces premature senescence due to lamin A defects in primary endothelial cells and progenitors after 48 h exposure. The cells used were non-aged as extracted from cord blood or umbilical vein, allowing one to consider that other senescence pathways were not activated and that the observed alterations were specific of prelamin A accumulation. Both mature endothelial cells and precursors were sensitive to prelamin accumulation and thus, could be used in the future as a valuable model to test different approaches aimed at specifically reversing lamin A-related cells senescence.
如在哈钦森-吉尔福德早衰综合征中所观察到的，核纤层蛋白A成熟缺陷会导致早衰综合征和严重的动脉粥样硬化。在与年龄相关的动脉粥样硬化中，内皮细胞的几种细胞衰老特征已得到表征，包括端粒缩短和氧化应激增加。然而，迄今为止，关于这些细胞中核纤层蛋白A的改变知之甚少。
研究核纤层蛋白A相关的衰老及其对原代内皮细胞激活状态的影响。
使用从人脐静脉或脐带血中获取的健康原代内皮细胞和祖细胞。通过蛋白酶抑制剂（阿扎那韦）处理48小时诱导核纤层蛋白A缺陷。
我们发现蛋白酶抑制剂处理导致法尼基化前体核纤层蛋白A积累，在分化的和祖细胞内皮细胞中均诱导核形态异常和早衰。成熟内皮细胞中ICAM-1依赖性激活和单核细胞黏附增加。同时，内皮祖细胞在基质胶中形成微血管网络的能力下降。当在成熟和祖细胞内皮细胞中联合使用普伐他汀和唑来膦酸处理细胞时，蛋白酶抑制剂处理对核形态的影响得以逆转。用靶向核纤层蛋白A特异性剪接位点的吗啉代反义寡核苷酸也证明了逆转作用。
本研究表明，蛋白酶抑制剂处理在暴露48小时后可在原代内皮细胞和祖细胞中因核纤层蛋白A缺陷而重现早衰。所使用的细胞是从脐带血或脐静脉中提取的非衰老细胞，这使得人们可以认为其他衰老途径未被激活，且观察到的改变是前体核纤层蛋白A积累所特有的。成熟内皮细胞和前体细胞均对前体核纤层蛋白积累敏感，因此，未来可作为一种有价值的模型来测试旨在特异性逆转核纤层蛋白A相关细胞衰老的不同方法。
