title: Sphingoid bases inhibit acid-induced demineralization of hydroxyapatite.
abstract: Calcium hydroxyapatite (HAp), the main constituent of dental enamel, is inherently susceptible to the etching and dissolving action of acids, resulting in tooth decay such as dental caries and dental erosion. Since the prevalence of erosive wear is gradually increasing, there is urgent need for agents that protect the enamel against erosive attacks. In the present study we studied in vitro the anti-erosive effects of a number of sphingolipids and sphingoid bases, which form the backbone of sphingolipids. Pretreatment of HAp discs with sphingosine, phytosphingosine (PHS), PHS phosphate and sphinganine significantly protected these against acid-induced demineralization by 80 ± 17%, 78 ± 17%, 78 ± 7% and 81 ± 8%, respectively (p < 0.001). On the other hand, sphingomyelin, acetyl PHS, octanoyl PHS and stearoyl PHS had no anti-erosive effects. Atomic force measurement revealed that HAp discs treated with PHS were almost completely and homogeneously covered by patches of PHS. This suggests that PHS and other sphingoid bases form layers on the surface of HAp, which act as diffusion barriers against H(+) ions. In principle, these anti-erosive properties make PHS and related sphingosines promising and attractive candidates as ingredients in oral care products.
authors.affiliation: Department of Periodontology and Oral Biochemistry, Academic Centre for Dentistry Amsterdam (ACTA), Vrije Universiteit and Universiteit van Amsterdam, Amsterdam, The Netherlands.
authors.forename: Marianne
authors.initials: M
authors.lastname: Valentijn-Benz
authors.forename: Wim
authors.initials: W
authors.lastname: van 't Hof
authors.forename: Floris J
authors.initials: FJ
authors.lastname: Bikker
authors.forename: Kamran
authors.initials: K
authors.lastname: Nazmi
authors.forename: Henk S
authors.initials: HS
authors.lastname: Brand
authors.forename: Javier
authors.initials: J
authors.lastname: Sotres
authors.forename: Liselott
authors.initials: L
authors.lastname: Lindh
authors.forename: Thomas
authors.initials: T
authors.lastname: Arnebrant
authors.forename: Enno C I
authors.initials: EC
authors.lastname: Veerman
mesh_terms: D000327:Adsorption; D019343:Citric Acid / Q000737:chemistry; D044622:Dental Pellicle / Q000737:chemistry; D004058:Diffusion; D017886:Durapatite / Q000737:chemistry*; D004492:Edetic Acid / Q000737:chemistry; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008422:Materials Testing; D018625:Microscopy, Atomic Force; D020011:Protective Agents / Q000737:chemistry*; D011493:Protein Kinase C / Q000037:antagonists & inhibitors; D013107:Sphingolipids / Q000737:chemistry*; D013109:Sphingomyelins / Q000737:chemistry; D013110:Sphingosine / Q000031:analogs & derivatives / Q000737:chemistry; D013499:Surface Properties; D013997:Time Factors; D014077:Tooth Erosion / Q000378:metabolism*
chemical_list: D020011:Protective Agents; D013107:Sphingolipids; D013109:Sphingomyelins; C117422:phytosphingosine-1-phosphate; D019343:Citric Acid; D017886:Durapatite; D004492:Edetic Acid; D011493:Protein Kinase C; C012491:phytosphingosine; D013110:Sphingosine; C005682:safingol