Li Chan, Liu Zhaoya, Chen Mengshi, Zhang Liyang, Shi Ruizheng, Zhong Hua
Department of Cardiovascular Medicine, Xiangya Hospital, Central South University, No. 87 Xiangya Road, Changsha 410008, China.
National Clinical Research Center for Geriatric Disorders, Xiangya Hospital, Changsha 410008, China.
Biology (Basel). 2022 Dec 26;12(1):42. doi: 10.3390/biology12010042.
The senescence of vascular endothelial cells (ECs) is characterized as a hallmark of vascular aging, which leads to the initiation, progress, and advancement of cardiovascular diseases. However, the mechanism of the ECs senescence remains elusive. In this study, thoracic aortas were separated from young (8-week-old) and aged (18-month-old) mice. Decreased Ctsl expression and increased vascular remodeling were observed in senescent aorta. HO was used to induce human umbilical vein endothelial cells (HUVECs) senescence, as shown by increased SA-β-gal positive cells and upregulated p21 level. CTSV significantly decreased after HO treatment, while over-expression of CTSV by adenovirus reduced cellular senescence. RNA sequencing analysis was conducted subsequently, and ALDH1A2 was observed to significantly increased in HO group and decreased after over-expression of CTSV. This result was further confirmed by RT-PCR and WB. Moreover, over-expression of CTSV reduced the increase of ERK1/2 and AKT phosphorylation induced by HO. Additionally, retinoic acid (RA), the major production of ALDH1A2, was added to CTSV over-expressed senescent HUVECs. Administration of RA activated AKT and ERK1/2, induced the expression of p21, and enhanced SA-β-gal positive cells, while not affecting the expression of CTSV and ALDH1A2. These results were further confirmed in doxorubicin (DOX)-induced senescent ECs. In conclude, we have identified that Ctsl/CTSV plays a key role in ECs senescence by regulating ALDH1A2 to activate AKT/ ERK1/2-P21 pathway. Therefore, targeting Ctsl/CTSV may be a potential therapeutic strategy in EC senescence.
血管内皮细胞（ECs）的衰老被视为血管老化的一个标志，它会引发心血管疾病的起始、发展和恶化。然而，ECs衰老的机制仍不清楚。在本研究中，从年轻（8周龄）和老年（18月龄）小鼠中分离出胸主动脉。在衰老的主动脉中观察到组织蛋白酶L（Ctsl）表达降低和血管重塑增加。用羟基脲（HO）诱导人脐静脉内皮细胞（HUVECs）衰老，衰老相关β-半乳糖苷酶（SA-β-gal）阳性细胞增加和p21水平上调表明了这一点。HO处理后组织蛋白酶V（CTSV）显著降低，而通过腺病毒过表达CTSV可减少细胞衰老。随后进行RNA测序分析，观察到HO组中视黄醛脱氢酶1A2（ALDH1A2）显著增加，CTSV过表达后降低。逆转录聚合酶链反应（RT-PCR）和蛋白质免疫印迹法（WB）进一步证实了这一结果。此外，CTSV过表达减少了HO诱导的细胞外信号调节激酶1/2（ERK1/2）和蛋白激酶B（AKT）磷酸化的增加。此外，将ALDH1A2的主要产物视黄酸（RA）添加到过表达CTSV的衰老HUVECs中。给予RA可激活AKT和ERK1/2，诱导p21的表达，并增加SA-β-gal阳性细胞，而不影响CTSV和ALDH1A2的表达。在阿霉素（DOX）诱导的衰老ECs中进一步证实了这些结果。总之，我们已经确定Ctsl/CTSV通过调节ALDH1A2激活AKT/ERK1/2-P21通路在ECs衰老中起关键作用。因此，靶向Ctsl/CTSV可能是ECs衰老的一种潜在治疗策略。
