title: Riboflavin and photoproducts in MC3T3-E1 differentiation.
abstract: Photoderivatives of riboflavin can modulate the proliferation and survival of cancer cells. In this work, we examined the influence of riboflavin and photoderivatives on osteoblast differentiation induced by ascorbic acid and β-glycerophosphate. These compounds decreased the osteoblast proliferation, increased the alkaline phosphatase activity, promoted a reduction in matrix metalloproteinase-2 activity and the decreased in the OPG/RANKL ratio. The effects of flavins on osteoblasts were unrelated to the antioxidant activity of these compounds. The biological activity of osteogenic medium containing riboflavin and its photoderivatives involved the activation of different signaling pathways (AKT, FAK, CaMKII), caspases-3, -8 and -9, and up-regulation of the expression and/or stabilization of osteoblastic transcription factors (Runx2 and β-catenin). These findings suggest a potential use of flavins as adjuvants to improve bone metabolism.
authors.affiliation: Departamento de Bioquímica, Instituto de Biologia, Universidade Estadual de Campinas (UNICAMP), CP6109, 13083-970 Campinas, SP, Brazil. ahcnfoa@yahoo.com.br
authors.forename: Antonio Hernandes
authors.initials: AH
authors.lastname: Chaves Neto
authors.forename: Claudia Lumy
authors.initials: CL
authors.lastname: Yano
authors.forename: Edgar Julian
authors.initials: EJ
authors.lastname: Paredes-Gamero
authors.forename: Daisy
authors.initials: D
authors.lastname: Machado
authors.forename: Giselle Zenker
authors.initials: GZ
authors.lastname: Justo
authors.forename: Maikel P
authors.initials: MP
authors.lastname: Peppelenbosch
authors.forename: Carmen Veríssima
authors.initials: CV
authors.lastname: Ferreira
mesh_terms: D016475:3T3 Cells; D000818:Animals; D020169:Caspases / Q000187:drug effects / Q000378:metabolism; D002454:Cell Differentiation / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects; D005415:Flavins / Q000494:pharmacology*; D051379:Mice; D010006:Osteoblasts / Q000378:metabolism; D010782:Photolysis; D012256:Riboflavin / Q000737:chemistry / Q000494:pharmacology*; D015398:Signal Transduction / Q000187:drug effects; D015854:Up-Regulation / Q000187:drug effects; D014803:Vitamin B Complex / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D005415:Flavins; D014803:Vitamin B Complex; D020169:Caspases; D012256:Riboflavin