Protein carbonylation associated with nickel liberation in orthodontic gingival overgrowth

• Published in: Archives of oral biology 2021-05, Vol.125, p.105103-105103, Article 105103
• Main Authors: Orozco-Páez, Jennifer, Méndez-Rodríguez, María A., Rodríguez-Cavallo, Erika, Díaz-Caballero, Antonio, Méndez-Cuadro, Darío
• Format: Article
• Language: English
• Subjects: Dentistry; Gingiva; Gingival Overgrowth; Gingivectomy; Humans; Nickel; Orthodontic Appliances; Orthodontic brackets; Protein Carbonylation
• ISSN: 0003-9969; 1879-1506
• DOI: 10.1016/j.archoralbio.2021.105103

•Nickel levels were greater in gingival tissue of patients with orthodontic appliances.•The highest protein carbonylation was found in patients with gingival enlargement.•Patients with history of orthodontics also showed intense protein carbonylated bands.•Teneurin-4 and Lysine-specific demethylase 5B were identified in carbonylated bands. To determine nickel levels and their impact on protein carbonylation in gum samples from patients with gingival overgrowth by orthodontic treatment. A retrospective observational study with 33 patients divided into three groups. Group 1 patients with gingival overgrowth by orthodontic appliances; group 2 patients without gingival overgrowth but with a history of orthodontic treatment; group 3 patients without overgrowth and history of orthodontic appliances. Nickel level in gingiva samples was measured by atomic absorption while protein carbonylation was determined by Western Blot. Furthermore, three proteins were identified in carbonylated protein bands by mass spectrometry. Statistically significant differences (p < 0,05) in tissue nickel levels among groups were established (nickel levels group 1: 1.33 ± 1.52; group 2: 0.33 ± 0.44; group 3: 0.20 ± 0.22 μg Ni/g tissue). Protein carbonylation was higher in patients with gingival enlargement (group 1) and history of appliance use (group 2) than controls (group 3). It was observed that band A of the Western blots presented the highest intensity (Rf 0.23) with an average intensity of 4.133.830 ± 1.958.569 for group 1; 4.420.146 ± 1.594.679 for group 2 and 2.110. 727 ± 1.640.721 for group 3. Also, the proteins Teneurin-4, Bromodomain adjacent to zinc finger domain protein 2B, Lysine-specific demethylase 5B, and Serum albumin, were identified from oxidized bands. The gum of patients with gingival overgrowth by orthodontic appliances contains higher nickel residues and carbonylation of its proteins.