title: Significant modifications of the salivary proteome potentially associated with complications of Down syndrome revealed by top-down proteomics.
abstract: People with Down syndrome, a frequent genetic disorder in humans, have increased risk of health problems associated with this condition. One clinical feature of Down syndrome is the increased prevalence and severity of periodontal disease in comparison with the general population. Because saliva plays an important role in maintaining oral health, in the present study the salivary proteome of Down syndrome subjects was investigated to explore modifications with respect to healthy subjects. Whole saliva of 36 Down syndrome subjects, divided in the age groups 10-17 yr and 18-50 yr, was analyzed by a top-down proteomic approach, based on the high performance liquid chromatography-electrospray ionization-MS analysis of the intact proteins and peptides, and the qualitative and quantitative profiles were compared with sex- and age-matched control groups. The results showed the following interesting features: 1) as opposed to controls, in Down syndrome subjects the concentration of the major salivary proteins of gland origin did not increase with age; as a consequence concentration of acidic proline rich proteins and S cystatins were found significantly reduced in older Down syndrome subjects with respect to matched controls; 2) levels of the antimicrobial α-defensins 1 and 2 and histatins 3 and 5 were significantly increased in whole saliva of older Down syndrome subjects with respect to controls; 3) S100A7, S100A8, and S100A12 levels were significantly increased in whole saliva of Down syndrome subjects in comparison with controls. The increased level of S100A7 and S100A12 may be of particular interest as a biomarker of early onset Alzheimer's disease, which is frequently associated with Down syndrome.
authors.affiliation: Dipartimento di Scienze della Vita e dell'Ambiente, Università di Cagliari, Monserrato (CA), Italy. tcabras@unica.it
authors.forename: Tiziana
authors.initials: T
authors.lastname: Cabras
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Pisano
authors.forename: Caterina
authors.initials: C
authors.lastname: Montaldo
authors.forename: Maria Rita
authors.initials: MR
authors.lastname: Giuca
authors.forename: Federica
authors.initials: F
authors.lastname: Iavarone
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Zampino
authors.forename: Massimo
authors.initials: M
authors.lastname: Castagnola
authors.forename: Irene
authors.initials: I
authors.lastname: Messana
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D004314:Down Syndrome / Q000378:metabolism*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D020543:Proteome; D040901:Proteomics; D012463:Saliva / Q000378:metabolism; D012471:Salivary Proteins and Peptides / Q000378:metabolism*; D055815:Young Adult
chemical_list: D020543:Proteome; D012471:Salivary Proteins and Peptides