A novel dual-action antimicrobial peptide for caries management. (August 2021)

• Record Type: Journal Article
• Authors: Niu, John Yun; Yin, Iris Xiaoxue; Wu, William Ka Kei; Li, Quan-Li; Mei, May Lei; Chu, Chun Hung
• Is Part Of: Journal of dentistry. Volume 111(2021)
• Publication Date: 2021-08
• Subjects: Caries -- Prevention -- Mineralisation -- Peptides -- Antimicrobial; Dentistry -- Periodicals; Dentistry -- Periodicals; Dentisterie -- Périodiques; Electronic journals; 617.6005
• DOI: 10.1016/j.jdent.2021.103729
• Languages: English
• ISSNs: 0300-5712

Abstract

Abstract: Objectives: To develop a novel dual-action peptide with antimicrobial and mineralising properties. Methods: A novel peptide, namely GA-KR12, was synthesised through grafting gallic acid to KR12. The secondary structure of GA-KR12 was evaluated by circular dichroism spectroscopy. The stability was evaluated by high-performance liquid chromatography. The cytotoxicity was evaluated by a mitochondrial dehydrogenase activity assay. The antimicrobial properties against common cariogenic species were evaluated by minimum inhibitory concentration (MIC) and minimum bactericidal/fungicidal concentration (MBC/MFC). The morphology of cariogenic species was analysed by transmission electron microscope (TEM). To assess the mineralising effect of GA-KR12 on enamel, the lesion depths, mineral loss, surface morphology, calcium-to-phosphorus ratio and crystal characteristics were determined using micro-computed tomography, scanning electron microscopy (SEM) and energy dispersive spectroscopy X-ray diffraction, respectively. Results: GA-KR12 did not exhibit cytotoxicity against HGF. Around 82% of the GA-KR12 remained in human saliva at 37°C for 1 h. The MIC and MBC/MFC against the tested species were 10-320 μM and 20-1, 280 μM, respectively. GA-KR12 induced remarkable morphological defects in the tested species. The enamel treated with GA-KR12 had smaller lesion depths ( p < 0.001), less mineral loss ( p < 0.001) and higher calcium-to-phosphorus molar ratios ( p < 0.001) than those in the enamel treated with water. SEM showed a well-organised prism pattern in enamel treated with GA-KR12. X-ray diffraction revealed that the hydroxyapatite on the enamel treated with GA-KR12 was better crystalised. Conclusions: This study developed a biocompatible and stable peptide which inhibited the growth of cariogenic species and mineralised the enamel caries. Clinical significance: The novel dual-action peptide, GA-KR12, is potential applicable in the management of caries.