Checchi L, Ciapetti G, Monaco G, Ori G
School of Dentistry, University of Bologna, Italy.
J Clin Periodontol. 1999 Oct;26(10):636-42. doi: 10.1034/j.1600-051x.1999.261002.x.
The aim of the present study was to examine: (1) the effects of nicotine on human gingival fibroblasts (HGF); (2) differences between smokers (> or = 10 cigarettes/day at least for 5 years) and non-smokers; (3) differences between patients of different age. HGF were obtained, through biopsies during periodontal surgical procedures, from 15 patients which were divided in 4 groups: 4 patients, smokers aged < or = 25 years; 4 patients, non-smokers aged < or = 25 years; 3 patients, smokers aged > or = 40 years; 4 patients, non-smokers aged > or = 40 years. Nicotine has been tested in 3 different concentrations: 6 microg/ml; 60 microg/ml; 600 microg/ml. To assess cells viability, the neutral red (NR) test was used; to evaluate cell proliferation, the Hoechst test was employed. After 48 h of nicotine exposure, it was found that 600 microg/ml nicotine was strongly cytotoxic to HGF of all groups, with a significant reduction of both proliferation and viability of cells versus control. Comparison between groups of the same age: when comparing untreated HGF (i.e., control values) of smokers < or = 25 years versus non-smokers < or = 25 years, cell proliferation, but not viability, was found to be increased in smokers. Both viability and proliferation of control cells of smokers > or = 40 years were increased versus non-smokers > or = 40 years. HGF of non-smokers < or = 25 years, when exposed to nicotine 600 microg/ml, have less viability and proliferation than HGF of smokers of the same age. Comparison between groups of different age: In the smoker group, untreated HGF (i.e., control values) had similar viability and proliferation, irrespective of age, but nicotine 600 microg/ml kills more HGF in smokers < or = 25 years than in smokers > or = 40 years. In non-smokers, untreated HGF < or = 25 years replicate less, but are not less viable than HGF > or = 40 years. When challenged with nicotine 600 microg/ml, HGF < or = 25 years were less viable than HGF > or = 40 years. From this study, it appears that the smoking history and the patient age could be relevant for final evaluation of the results, since HGF from smokers are less sensitive to nicotine than HGF from non-smokers, and cells from older donors are more resistant to nicotine than cells from younger donors.
（1）尼古丁对人牙龈成纤维细胞（HGF）的影响；（2）吸烟者（每天至少吸10支烟，至少持续5年）与非吸烟者之间的差异；（3）不同年龄患者之间的差异。通过牙周手术活检从15名患者中获取HGF，这些患者被分为4组：4名年龄≤25岁的吸烟患者；4名年龄≤25岁的非吸烟患者；3名年龄≥40岁的吸烟患者；4名年龄≥40岁的非吸烟患者。对尼古丁进行了3种不同浓度的测试：6微克/毫升；60微克/毫升；600微克/毫升。使用中性红（NR）试验评估细胞活力；采用Hoechst试验评估细胞增殖。尼古丁暴露48小时后，发现600微克/毫升的尼古丁对所有组的HGF均具有强烈的细胞毒性，与对照组相比，细胞的增殖和活力均显著降低。同一年龄组之间的比较：当比较年龄≤25岁的吸烟患者与年龄≤25岁的非吸烟患者的未处理HGF（即对照值）时，发现吸烟者的细胞增殖增加，但细胞活力未增加。与年龄≥40岁的非吸烟患者相比，年龄≥40岁的吸烟患者的对照细胞的活力和增殖均增加。年龄≤25岁的非吸烟患者的HGF在暴露于600微克/毫升尼古丁时，其活力和增殖低于同年龄的吸烟患者的HGF。不同年龄组之间的比较：在吸烟组中，未处理的HGF（即对照值）具有相似的活力和增殖，与年龄无关，但600微克/毫升的尼古丁杀死年龄≤25岁的吸烟患者的HGF比杀死年龄≥40岁的吸烟患者的HGF更多。在非吸烟患者中，年龄≤25岁的未处理HGF增殖较少，但活力并不低于年龄≥40岁的HGF。当用600微克/毫升尼古丁进行刺激时，年龄≤25岁的HGF的活力低于年龄≥40岁的HGF。从这项研究来看，吸烟史和患者年龄可能与结果的最终评估相关，因为吸烟患者的HGF对尼古丁的敏感性低于非吸烟患者的HGF，并且老年供体的细胞比年轻供体的细胞对尼古丁更具抗性。
