title: Stimulation of bone marrow cells and bone formation by nacre: in vivo and in vitro studies.
abstract: There is frequently a loss of vertebral bone due to disease or aging. Nacre (mother of pearl from the oyster Pinctada maxima) stimulates bone cell differentiation and bone formation in vitro and in vivo. Experimental bone defects were prepared in the vertebrae of sheep and used to test the suitability of nacre as an injectable osteogenic biomaterial for treating vertebral bone loss. Twenty-one cavities were prepared in the first four upper lumbar vertebrae of 11 sheep and filled with nacre powder. The lumbar vertebrae were removed after 1 to 12 weeks, embedded undecalcified in methacrylate, and processed for histological studies. The nacre slowly dissolved and the experimental cavities contained a large active cell population. By 12 weeks, the experimental cavity was occupied by newly matured bone trabeculae in contact with or adjacent to the dissolving nacre. The functional new bone trabeculae were covered with osteoid lined with osteoblasts, indicating continuing bone formation. The in vitro study on rat bone marrow explants cultured with a water-soluble extract of the nacre organic matrix also resulted in the stimulation of osteogenic bone marrow cells with enhanced alkaline phosphatase activity. Thus, both the in vivo and in vitro findings suggest that nacre contains one or more signal molecules capable of activating osteogenic bone marrow cells.
authors.affiliation: Laboratoire de Physiologie Générale et Comparée, Muséum National d'Histoire Naturelle, Paris, France.
authors.forename: M
authors.initials: M
authors.lastname: Lamghari
authors.forename: M J
authors.initials: MJ
authors.lastname: Almeida
authors.forename: S
authors.initials: S
authors.lastname: Berland
authors.forename: H
authors.initials: H
authors.lastname: Huet
authors.forename: A
authors.initials: A
authors.lastname: Laurent
authors.forename: C
authors.initials: C
authors.lastname: Milet
authors.forename: E
authors.initials: E
authors.lastname: Lopez
mesh_terms: D000469:Alkaline Phosphatase / Q000378:metabolism; D000818:Animals; D001672:Biocompatible Materials / Q000494:pharmacology*; D001846:Bone Development / Q000187:drug effects*; D001854:Bone Marrow Cells / Q000166:cytology / Q000187:drug effects* / Q000201:enzymology; D002113:Calcification, Physiologic / Q000187:drug effects*; D002478:Cells, Cultured; D017077:Culture Media, Conditioned / Q000494:pharmacology; D004195:Disease Models, Animal; D005269:Femur / Q000166:cytology; D008159:Lumbar Vertebrae / Q000187:drug effects* / Q000473:pathology / Q000601:surgery; D008297:Male; D008852:Microradiography; D010006:Osteoblasts / Q000187:drug effects / Q000201:enzymology; D010125:Ostreidae; D011208:Powders; D051381:Rats; D017208:Rats, Wistar; D012756:Sheep
chemical_list: D001672:Biocompatible Materials; D017077:Culture Media, Conditioned; D011208:Powders; D000469:Alkaline Phosphatase