尼古丁在被动吸烟大鼠口腔硬组织中的分布及其对牙周膜干细胞的影响

Distribution of nicotine in oral hard tissue of passive smoking rats and the effect on PDLS

目的探究被动吸烟及戒除被动吸烟后大鼠血液及口腔硬组织中的尼古丁分布情况和变化规律,并通过体外尼古丁对牙周膜干细胞(PDLSCs)增殖及成骨能力的影响,间接证实口腔组织中尼古丁沉积的危害。方法建立被动吸烟大鼠模型,采用液相色谱-串联质谱法检测大鼠血液、牙齿和牙槽骨中尼古丁分布情况。体外尼古丁刺激PDLSCs,通过CCK-8、茜素红染色、Western Blot检测尼古丁对PDLSCs增殖能力和成骨能力的影响。结果在为期3个月的被动吸烟中,大鼠血液、牙槽骨,牙齿中的尼古丁浓度分别在2月、1月、2月达到峰值,随后逐渐降低;戒除被动吸烟后,尼古丁仍维持一定浓度水平。体外尼古丁刺激PDLSCs后,细胞增殖受到抑制,矿化结节显著减少,ALP、Runx2、OPG等蛋白表达均下调。结论尼古丁在被动吸烟大鼠血液、牙齿和牙槽骨中的分布情况具有时间相关性,戒除被动吸烟后,尼古丁可长期蓄积于体内,对牙周膜干细胞的增殖和成骨分化产生不利影响。

Objective To investigate the distribution and the change of nicotine in blood and oral hard tissues of rats after passive smoking and abstaining from passive smoking,and indirectly confirm the harm of nicotine deposition in oral tissue through the effects of nicotine on the proliferation and osteogenic ability of PDLSCs in vitro.Methods The distribution of nicotine in blood,teeth and alveolar bone of rats was determined by liquid chromatography-tandem mass spectrometry(LC-MS).Different concentration of nicotine was used to stimulate PDLSCs,CCK-8,alizarin red staining and Western Blotting was used to detect the proliferation and osteogenic ability of PDLSCs respectively.Results During 3 months of passive smoking,nicotine concentrations in blood,alveolar bone,teeth peaked in February,January and gradually decreased,and nicotine levels were maintained after withdrawal from passive smoking.After in vitro nicotine stimulation,the proliferation of PDLSCs was significantly inhibited.The mineralized nodules were significantly reduced after osteogenic induction.WB results showed that the expression of proteins such as ALP,Runx2,OPG were all downregulated.Conclusion The distribution of nicotine in the blood,teeth and alveolar bone of passive smoking rats has a time correlation.After giving up passive smoking,nicotine may be accumulated in the body for a long time,causing adverse effects on the proliferation and osteogenic differentiation of PDLSCs.