Department of General Dentistry, Shanghai 9th People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai Key Laboratory of Stomatology. Shanghai, China.
Int Endod J. 2012 Dec;45(12):1074-9. doi: 10.1111/j.1365-2591.2012.02064.x. Epub 2012 May 2.
To establish whether autophagy is involved in dental pulp cell (DPC) senescence, so as to better understand the mechanism of the ageing process within the dental pulp.
Human DPCs obtained from intact molars and premolars were cultured and serially passaged. Senescence-β-galactosidase (SA-β-gal) staining was performed to assess DPC senescence, which is considered to be the senescence of cells in culture after a series of passages. Autophagic activity was analysed by Western blot for major autophagic proteins and transmission electron microscopy (TEM) for autophagic vacuoles in both young and senescent cells. Statistical analyses were performed using the Student's t-test.
Senescence-β-galactosidase staining was higher in senescent DPC than in young cells (P = 0.011). Western blot revealed senescent DPCs had greater expression of autophagic proteins (microtubule-associated protein light chain 3 and Beclin 1) than young cells (P = 0.04, P = 0.001). Transmission electron microscopy revealed more autophagic vacuoles in senescent DPCs compared to young cells (P = 0.029).
Expression of autophagic proteins (microtubule-associated protein light chain 3 and Beclin 1) increased in senescent DPCs compare to young cells. More autophagic vacuoles were observed in senescent DPCs by TEM. Collectively, these data imply that autophagic activity increased in senescent DPCs.
探讨自噬是否参与牙髓细胞（DPC）衰老，从而更好地理解牙髓内衰老过程的机制。
从完整的磨牙和前磨牙中分离培养人牙髓细胞，通过β-半乳糖苷酶（SA-β-gal）染色评估 DPC 衰老，这被认为是细胞在经过一系列传代培养后的衰老。通过 Western blot 分析自噬相关蛋白和透射电镜（TEM）观察自噬小体，评估年轻细胞和衰老细胞中的自噬活性。采用 Student's t 检验进行统计学分析。
衰老的 DPC 中β-半乳糖苷酶染色较年轻细胞更高（P=0.011）。Western blot 显示衰老的 DPC 中自噬相关蛋白（微管相关蛋白轻链 3 和 Beclin 1）表达高于年轻细胞（P=0.04，P=0.001）。透射电镜显示衰老的 DPC 中有更多的自噬小体（P=0.029）。
与年轻细胞相比，衰老的 DPC 中自噬相关蛋白（微管相关蛋白轻链 3 和 Beclin 1）的表达增加。TEM 观察到衰老的 DPC 中有更多的自噬小体。综上所述，这些数据表明衰老的 DPC 中自噬活性增加。
