Bone mineralization

Abstract

This review attempts to summarize the findings made available by the literature on the mineralization of bone. The types of bone, their structures and compositions, the nature and organization of organic and inorganic matter, the organic-inorganic relationships, and the mineralization mechanism itself, are the main topics of the present review. As in other hard tissues, bone mineralization occurs in, and is conditioned by, the components of the organic matrix. Collagen fibrils have long been considered the factor that is able to induce the deposition of apatite crystallites through a process of heterogeneous nucleation. Interfibrillar non-collagenous proteins are now considered to be co-factors that permit crystallite deposition. The main components of these proteins are reviewed. It is hypothesized that two independent types of mineral are present in bone, one contained in the collagen fibrils and corresponding to the granular, electron-dense bands, and the other contained in the interfibrillar spaces and corresponding to needle- and filament-like crystals. The deposition mechanism of these mineral structures remains elusive. The formation of the crystallites through an epitaxial mechanism is discussed.

Bioactive vapor deposited calcium‐phosphate silica sol–gel particles for directing osteoblast behavior

“…Native bone hydroxyapatite (HA) is often defined of having a Ca:P ratio of 1.67 so most bioactive materials aim to induce mineral formation at this benchmark. However, the actual Ca:P ratio for bone mineral ranges from 1.57 to 1.71, and changes with the stage of mineral maturation‐increasing from 1.35 in early calcification of nodules . Altering the amount of calcium and phosphate available for release within the particles to the aqueous environment may lead to changes in the composition of the apatite mineral formed on the substrate to achieve a Ca:P ratio closer to mature bone HA.…”

Favorable effect of dietary vitamin C on bone mineral density in postmenopausal women (KNHANES IV, 2009): discrepancies regarding skeletal sites, age, and vitamin D status

“…Some studies of humans also showed that high plasma levels or dietary intake of antioxidants is associated with increased bone mineral density [13][14][15]. In addition, vitamin C is a cofactor in collagen formation and hydroxylation of lysine and proline [16], which are important for bone maintenance [17]. This nutrient also stimulates in vitro osteoblast differentiation and alkaline phosphatase activity, thereby contributing to bone formation [18,19].…”

Inferring causal relationships between phenotypes using summary statistics from genome-wide association studies

“…This was consistent with previous finding that high plasma levels or dietary intake of antioxidants is associated with increased BMD (Maggio et al 2003; Sugiura et al 2011). In addition, ascorbate is a cofactor in collagen formation and hydroxylation of lysine and proline (Peterkofsky et al 1994), which is important for bone maintenance (Bonucci 2012). Another example was aspartylphenylalanine, which is a dipeptide composed of aspartate and phenylalanine.…”