Suppr超能文献

人髓核软骨细胞的体外寿命和衰老机制

In vitro lifespan and senescence mechanisms of human nucleus pulposus chondrocytes.

作者信息

Jeong Seo-Won, Lee Jun-Seok, Kim Ki-Won

机构信息

Orthopaedic Research Center, St. Mary's Hospital, College of Medicine, The Catholic University of Korea, 62 Yoido-dong, Youngdeungpo-ku, Seoul 150-010, Korea.

Department of Orthopaedic Surgery, Dongshin General Hospital, Seoul, Korea.

出版信息

Spine J. 2014 Mar 1;14(3):499-504. doi: 10.1016/j.spinee.2013.06.099. Epub 2013 Dec 15.

Abstract

BACKGROUND CONTEXT

Our previous in vivo study demonstrated that human nucleus pulposus chondrocytes (NPCs) in aging discs exhibited characteristic senescent features such as an increased senescence-associated β-galactosidase (SA-β-gal) expression, shortened telomere, and decreased telomerase activity. The replicative p53-p21-pRB pathway, rather than the stress-induced p16-pRB pathway, played a more important role in the senescence of NPCs in an in vivo condition, although there is a situation in which both the pathways can be activated simultaneously. However, the in vitro lifespan and senescence mechanisms of human NPCs remain unclear.

PURPOSE

To evaluate the underlying mechanisms of in vitro lifespan and in vitro senescence of the human NPCs and to verify whether the in vitro senescence mechanisms of the human NPC can represent the in vivo aging mechanisms of the cell.

STUDY DESIGN/SETTING: An in vitro study.

METHODS

We serially cultivated human NPCs from patients of different ages (35, 42, 55, 66, and 76 years) until the cells reached the end of their in vitro lifespan. During each subcultivation, we calculated NPCs cumulative population doubling level (PDL) and examined senescence markers (SA-β-gal, telomere length, telomerase activity, and p53, p21, pRB, and p16 expressions).

RESULTS

The cumulative PDLs of the NPCs from patients aged 35, 42 55, 66, and 76 years were 32, 29, 11, 9, and 11, respectively. The younger patients (35 and 42 years) had a higher mean of cumulative PDLs than the elderly patients did (55, 66, and 76 years; 30.5 vs. 10.3; p=.001). In addition, there was a significant, negative correlation between the cumulative PDLs and patient's age (r=-0.89; p=.04). With advancing culture passages, the NPCs irrespective of patient's age exhibited characteristic senescent features, such as an increase in SA-β-gal expression, shortening of telomeres, decrease in telomerase activity, and activation of both replicative p53-p21-pRB and stress-induced p16-pRB pathways. However, all the senescent features occurred at the earlier passages in elderly compared with younger patients.

CONCLUSIONS

The present study demonstrated that the human NPCs had a finite in vitro lifespan, which declined with host aging. The in vitro lifespan was determined by both replicative and stress-induced senescence mechanisms. The similarity in the in vitro senescent features with those apparent in the previous in vivo study suggests a possibility of the in vitro senescence mechanisms of the human NPC as a model of the in vivo aging mechanisms of the cell for future studies.

摘要

背景

我们之前的体内研究表明,衰老椎间盘内的人髓核软骨细胞(NPC)呈现出特征性的衰老特征,如衰老相关β-半乳糖苷酶(SA-β-gal)表达增加、端粒缩短以及端粒酶活性降低。在体内条件下,复制性p53-p21-pRB途径而非应激诱导的p16-pRB途径在NPC衰老过程中发挥更重要的作用,尽管存在两种途径可同时被激活的情况。然而,人NPC的体外寿命和衰老机制仍不清楚。

目的

评估人NPC体外寿命和体外衰老的潜在机制,并验证人NPC的体外衰老机制是否能代表细胞的体内衰老机制。

研究设计/场所:一项体外研究。

方法

我们对来自不同年龄(35、42、55、66和76岁)患者的人NPC进行连续培养,直至细胞达到其体外寿命终点。在每次传代培养过程中,我们计算NPC的累积群体倍增水平(PDL),并检测衰老标志物(SA-β-gal、端粒长度、端粒酶活性以及p53、p21、pRB和p16的表达)。

结果

35、42、55、66和76岁患者的NPC累积PDL分别为32、29、11、9和11。年轻患者(35和42岁)的累积PDL平均值高于老年患者(55、66和76岁;30.5对10.3;p = 0.001)。此外,累积PDL与患者年龄之间存在显著的负相关(r = -0.89;p = 0.04)。随着传代次数的增加,无论患者年龄如何,NPC均呈现出特征性的衰老特征,如SA-β-gal表达增加、端粒缩短、端粒酶活性降低以及复制性p53-p21-pRB和应激诱导的p16-pRB途径激活。然而,与年轻患者相比,所有衰老特征在老年患者中出现的传代更早。

结论

本研究表明,人NPC具有有限的体外寿命,且随宿主衰老而下降。体外寿命由复制性和应激诱导的衰老机制共同决定。体外衰老特征与之前体内研究中观察到的特征相似,这表明人NPC的体外衰老机制有可能作为未来研究细胞体内衰老机制的模型。

文献检索

告别复杂PubMed语法,用中文像聊天一样搜索,搜遍4000万医学文献。AI智能推荐,让科研检索更轻松。

立即免费搜索

文件翻译

保留排版,准确专业,支持PDF/Word/PPT等文件格式,支持 12+语言互译。

免费翻译文档

深度研究

AI帮你快速写综述,25分钟生成高质量综述,智能提取关键信息,辅助科研写作。

立即免费体验