title: Metabolic effects of vitamin D active metabolites in monolayer and micromass cultures of nucleus pulposus and annulus fibrosus cells isolated from human intervertebral disc.
abstract: Intragenic polymorphisms in the vitamin D receptor gene are linked to disc degeneration features, suggesting that alterations in the vitamer-mediated signalling could be involved in the pathophysiology of the disc and that interaction of disc cells with vitamin D metabolites may be critical for disc health. The vitamer-mediated modulation of disc cells proliferation, metabolic activity, extracellular matrix (ECM) genes expression and proteins production was investigated. It was stated that disc cells express vitamin D receptor and are very sensitive to metabolic stimuli. In monolayer cultures, 1,25(OH)(2)D(3), but not 24,25(OH)(2)D(3), determined an inhibition of the proliferation and regulated also the ECM genes expression in nucleus pulposus and annulus fibrosus cells. Micromass cultures induced a more physiologic expression pattern of extracellular matrix genes. Cells Treatment with vitamin D metabolites did not result in relevant modifications of glycosaminoglycans production, except for annulus cells, whose production was reduced after 1,25(OH)(2)D(3) treatment. Moreover, a reduced glycosaminoglycans staining in both cell types and a significant reduced aggrecan gene expression in annulus cells treated with 1,25(OH)(2)D(3) were observed. A reduction of collagen I and II staining in annulus cells 1,25(OH)(2)D(3) treated, in accordance with a downregulation of collagen genes expression, was also registered. Finally, the vitamin D receptor gene expression did not show significant metabolite-mediated modification in monolayer or micromass cultures. These findings could enhance new insights on the biochemical mechanisms regulated by vitamin D in disc cartilage and possibly involved in the development of physiological/pathological modifications of the disc.
authors.affiliation: I.R.C.C.S. Istituto Ortopedico Galeazzi, Via R. Galeazzi 4, 20161 Milano, Italy. alessandra.colombini@grupposandonato.it
authors.forename: Alessandra
authors.initials: A
authors.lastname: Colombini
authors.forename: Patrizia
authors.initials: P
authors.lastname: Lanteri
authors.forename: Giovanni
authors.initials: G
authors.lastname: Lombardi
authors.forename: Dalila
authors.initials: D
authors.lastname: Grasso
authors.forename: Camilla
authors.initials: C
authors.lastname: Recordati
authors.forename: Alessio
authors.initials: A
authors.lastname: Lovi
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Banfi
authors.forename: Roberto
authors.initials: R
authors.lastname: Bassani
authors.forename: Marco
authors.initials: M
authors.lastname: Brayda-Bruno
mesh_terms: D000328:Adult; D001483:Base Sequence; D049109:Cell Proliferation; D017931:DNA Primers; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007403:Intervertebral Disc / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D060888:Real-Time Polymerase Chain Reaction; D018167:Receptors, Calcitriol / Q000235:genetics; D014807:Vitamin D / Q000378:metabolism*
chemical_list: D017931:DNA Primers; D018167:Receptors, Calcitriol; D014807:Vitamin D