Gao J Y, Wang X J, Yu J P, An X J, Jia Z W, Guo X S
Department of Prosthodontics, Shanxi Provincial People's Hospital Affiliated to Shanxi Medical University, Taiyuan 030012, China.
Department of Orthopeadics, Shanxi Provincial People's Hospital Affiliated to Shanxi Medical University, Taiyuan 030012, China.
Zhonghua Kou Qiang Yi Xue Za Zhi. 2020 May 9;55(5):343-347. doi: 10.3760/cma.j.cn112144-20200216-00058.
To observe the effect of autophagy of condylar chondrocytes on apoptosis in temporomandibular joint osteoarthritis (TMJOA) of rats. Fourty male 2-month-old SPF SD rats were equally divided into sham group (20) and experimental group (20). UAC metal prosthesis was cemented to the left incisors of maxilla and mandible of the rats in experimental group rats. After 8 weeks, all rats were sacrificed and the temporomandibular joint was taken. Two groups of rat condylar chondrocytes were extracted and cultured in vitro to the third generation. Immunofluorescence technique was used to detect the levels of collagen Ⅱ and matrix metalloproteinase-13 (MMP-13) in chondrocytes. The level of light chain-3 (LC-3), an autophagy marker of chondrocytes, was detected. Immunohistochemical technique was used to detect the level glycogenin-1, a glycogen formation marker of chondrocyte, was detected. The level of caspase-3, an apoptosis marker of chondrocyte, was also detected. Tunel technique was used to detect the apoptosis rate of the two groups at 72 h. Cracking cell extraction of total protein, Western-blotting (WB) technology to detect the levels of collagen Ⅱ, MMP -13, LC-3, glycogenin-1, caspase-3 and make gray analysis. Compared with sham group, the level of collagen Ⅱ decreased, MMP-13 increased, LC-3 decreased, glycogenin-1 increased and caspase-3 increased in experimental group. The apoptosis rate of chondrocytes in experimentaal group [ (17.3±4.4) %] at 72h was higher than that in control group [ (5.6±2.1) %](10.732, 0.001) .WB bands gray statistical results show that the level of collagen Ⅱ in chondrocytes of experimental group (0.43±0.21) was lower than that of control group (0.71±0.26) (2.409, 0.043) , the level of MMP-13 in chondrocytes of experimental group (0.73±0.31) was higher than that of control group (0.24±0.10) (3.364, 0.010) , the level of LC-3 in chondrocytes of experimental group (0.09±0.04) was lower than that of control group (0.39±0.18) (3.638, 0.007) , the level of glycogenin-1 in chondrocytes of experimental group (0.68±0.30) was higher than that of control group (0.29±0.17) (2.529, 0.035) , the level of caspase-3 in chondrocytes of experimental group (0.19±0.08) was higher than that of control group (0.05±0.02) (3.796, 0.005) . The level of autophagy of condylar chondrocytes in temporomandibular joint of rats decreased, glycogen accumulation increased, the rate of chondrocyte apoptosis increased, and the number of chondrocytes decreased, resulting in degeneration of condylar cartilage tissue.
观察髁突软骨细胞自噬对大鼠颞下颌关节骨关节炎（TMJOA）中细胞凋亡的影响。将40只2月龄雄性SPF级SD大鼠平均分为假手术组（20只）和实验组（20只）。对实验组大鼠上颌和下颌的左切牙粘结UAC金属假体。8周后，处死所有大鼠并取出颞下颌关节。提取两组大鼠的髁突软骨细胞并体外培养至第三代。采用免疫荧光技术检测软骨细胞中Ⅱ型胶原蛋白和基质金属蛋白酶-13（MMP-13）的水平。检测软骨细胞自噬标志物轻链-3（LC-3）的水平。采用免疫组织化学技术检测软骨细胞糖原形成标志物糖原素-1的水平。还检测软骨细胞凋亡标志物半胱天冬酶-3的水平。采用Tunel技术检测两组在72小时时的凋亡率。裂解细胞提取总蛋白，采用蛋白质免疫印迹（WB）技术检测Ⅱ型胶原蛋白、MMP -13、LC-3、糖原素-1、半胱天冬酶-3的水平并进行灰度分析。与假手术组相比，实验组Ⅱ型胶原蛋白水平降低、MMP-13升高、LC-3降低、糖原素-1升高、半胱天冬酶-3升高。实验组软骨细胞在72小时时的凋亡率[（17.3±4.4）%]高于对照组[（5.6±2.1）%]（10.732，0.001）。WB条带灰度统计结果显示，实验组软骨细胞中Ⅱ型胶原蛋白水平（0.43±0.21）低于对照组（0.71±0.26）（2.409，0.043），实验组软骨细胞中MMP-13水平（0.73±0.31）高于对照组（0.24±0.10）（3.364，0.010），实验组软骨细胞中LC-3水平（0.09±0.04）低于对照组（0.39±0.18）（3.638，0.007），实验组软骨细胞中糖原素-1水平（0.68±0.30）高于对照组（0.29±0.17）（2.529，0.035），实验组软骨细胞中半胱天冬酶-3水平（0.19±0.08）高于对照组（0.05±0.02）（3.796，0.005）。大鼠颞下颌关节髁突软骨细胞自噬水平降低，糖原积累增加，软骨细胞凋亡率升高，软骨细胞数量减少，导致髁突软骨组织退变。
