白细胞介素18在腰椎间盘真空征患者体内的表达及作用

The expression and effect of interleukin-18 in vacuum of lumbar intervertebral disc

目的探讨白细胞介素18(IL-18)在腰椎间盘真空征患者体内的表达及作用。方法选取我院收治的腰椎间盘退变患者137例为研究对象,根据CT观察是否发生真空变形分为观察组(椎间盘真空症状,n=66)和对照组(非真空症状,n=71)。采用酶联免疫吸附试验检测两组患者血清样本中IL-18的含量,及两组髓核样本中蛋白多糖的含量。体外培养人退变椎间盘髓核细胞,使用浓度分别为0、50、100、200ng/mL的IL-18处理细胞,RT-PCR法检测细胞内基质金属蛋白酶3(MMP-3)mRNA转录水平;阿利新蓝法检测培养液中蛋白多糖含量;Western-blot检测p65、磷酸化p65(p-p65)、基质金属蛋白酶MMP-3及细胞因子IL-1β和TNF-α等蛋白表达水平。结果观察组血清中IL-18含量高于对照组,髓核组织中蛋白多糖含量低于对照组(均P<0.05)。不同浓度IL-18处理细胞后,MMP-3mRNA转录水平和蛋白表达水平呈现IL-18浓度依赖性升高(P<0.05)。蛋白多糖总量呈现IL-18浓度依赖性降低。细胞内p65的表达随IL-18浓度增加而降低,磷酸化p65(p-p65)的表达随IL-18浓度增加而增高。培养液中基质金属蛋白酶MMP-3蛋白及细胞因子IL-1β和TNF-α的分泌随IL-18浓度增加而增高。结论IL-18在腰椎间盘真空征患者体内呈高表达,通过激活NF-κB信号通路促进人退变椎间盘细胞分泌炎性因子和基质金属蛋白酶MMP-3,降低蛋白多糖合成,从而参与腰椎间盘真空变性的病理进展。

ObjectiveTo explore the expression and effect of interleukin-18 (IL-18) in patients with vacuum of lumbar intervertebral disc. Methods66 patients with vacuum found in intervertebral disc were classified into the observation group well the other 71 patients without vacuum found in intervertebral disc were classified into the control group. The expression of IL-18 in serum as well as the proteoglycan in the nucleus pulposus token from the two group were tested through enzymelinkedimmunosorbentassay (ELISA). Nucleus pulposus cells were treated with variousconcentrations of IL-18 (0ng/mL, 50ng/mL, 100ng/mL, 200ng/mL). The transcriptionallevel of Matrix metalloproteinase-3 (MMP-3) were tested by RT-PCR. Proteoglycan in the cell supernatant was tested by Alcian blue method. Then the expression of MMP-3, p-p65, p65, IL-1β and TNF-α were studied by Western-blot. ResultsThe expression of IL-18 in the observation group (214.74 ± 19.11 pg/mL) was higher than that in the control group (50.90 ± 37.62 pg/mL)( P < 0.05). However, the expression of proteoglycan in the observation group (52.415 ± 0.201 mg/g) was lower than that in the control group (161.415 ± 7.652 mg/g)( P < 0.05). After treated with IL-18, the transcriptionallevel of MMP-3 in the nucleus pulposus cells increased as the increase of the concentrations of IL-18 ( P < 0.05). The expression of proteoglycanin the nucleus pulposus cells were 2097.65 ± 23.10 mg/L,1088.54 ± 33.09 mg/L,767.04 ± 73.81 mg/L,531.65 ± 55.19 mg/L which decreased as the increase of the concentrations of IL-18 ( P < 0.05). The expression of MMP-3, p-p65, IL-1β and TNF-α were increased as the increase of the concentrations of IL-18, however the expression of p65 decreased. ConclusionThe expression IL-18 in patients with vacuum of lumbar intervertebral disc was high. It actives the NF-κB signal path to promote the expression of MMP-3 and inflammatory factors such as IL-1β and TNF-α which father prevent the biosynthesis of proteoglycan, so that to take part in the progression of vacuum of lumbar intervertebral disc.