Department of Pediatric Dentistry, School of Dentistry of Ribeirão Preto, Universidade de São Paulo, Av do Café, S/N, Ribeirão Preto, 14027-250, SP, Brazil.
Department of Oral and Maxillofacial Surgery, Universidade Positivo, Prof. Pedro Viriato Parigot de Souza Street, Cidade Industrial, Curitiba, 81280-330, Parana, Brazil.
Odontology. 2020 Jul;108(3):493-502. doi: 10.1007/s10266-019-00475-x. Epub 2019 Nov 18.
Genetic polymorphisms could be involved in the individual rate of OTM (orthodontic tooth movement) corresponding to the clinical phenomenon of "slow movers" and "fast movers". This study evaluated, if genetic polymorphisms in RANK, RANKL, OPG, COX2 and IL6 are associated with the expression of RANKL, OPG, COX2 and IL6 by human periodontal ligament (hPDL) fibroblasts during OTM. Primary hPDL fibroblasts from periodontal connective tissue of teeth extracted from 57 human subjects for medical reasons were collected, isolated, cultivated and characterized. To simulate orthodontic forces in PDL pressure areas, a physiological compressive force of 2 g/cm was applied to the hPDL fibroblasts under cell culture conditions at 70% confluency for 48 h, using a glass disc. Thereafter we analysed relative expression of RANKL, OPG, COX2 and IL6 by RT-qPCR. We also performed genotyping analysis of seven genetic polymorphisms in RANK, RANKL, OPG, COX2 and IL6. Relative gene expression was compared among the genotypes. The genotype TT in polymorphism rs9594738 (RANKL) had a higher RANKL expression in the recessive model (p = 0.021; TT vs. CT + CC). For polymorphism rs9594738 (RANKL), in the recessive model, TT was associated with a higher RANKL/OPG expression ratio (p = 0.013; TT vs. CT + CC). In the dominant model, GG genotype in rs5275 (COX2) was associated with a lower gene expression of COX2 (p = 0.04; GG vs. AA + AG). Genetic polymorphisms in genes associated with OTM affect the relative force-induced upregulation of these genes in hPDL fibroblasts.
遗传多态性可能与 OTM（正畸牙齿移动）的个体速率有关，这与“慢动者”和“快动者”的临床现象相对应。本研究评估了 RANK、RANKL、OPG、COX2 和 IL6 中的遗传多态性是否与 hPDL（人牙周韧带）成纤维细胞在 OTM 过程中 RANKL、OPG、COX2 和 IL6 的表达有关。从因医疗原因而从 57 名人类受试者中提取的牙齿牙周组织中收集、分离、培养和鉴定了原发性 hPDL 成纤维细胞。为了在 PDL 压力区模拟正畸力，在细胞培养条件下，在 70%汇合度下，使用玻璃盘将生理压缩力 2 g/cm 施加到 hPDL 成纤维细胞上 48 h。之后，我们通过 RT-qPCR 分析了 RANKL、OPG、COX2 和 IL6 的相对表达。我们还对 RANK、RANKL、OPG、COX2 和 IL6 中的七个遗传多态性进行了基因分型分析。比较了基因型之间的相对基因表达。在隐性模型中，rs9594738（RANKL）中的 TT 基因型具有更高的 RANKL 表达（p=0.021；TT 与 CT+CC）。对于 rs9594738（RANKL）多态性，在隐性模型中，TT 与更高的 RANKL/OPG 表达比值相关（p=0.013；TT 与 CT+CC）。在显性模型中，rs5275（COX2）中的 GG 基因型与 COX2 的基因表达降低相关（p=0.04；GG 与 AA+AG）。与 OTM 相关的基因中的遗传多态性会影响这些基因在 hPDL 成纤维细胞中相对力诱导的上调。
