Control of Osteoblast Function and Bone Extracellular Matrix Mineralization by Vitamin D

Bariatric surgery and bone disease: from clinical perspective to molecular insights

“…52 There is also recent and growing evidence that vitamin D has direct effects on bone cells through its interaction with specific vitamin D receptors. [53][54][55][56][57] These actions are not completely characterized but appear to include anabolic effects on osteoblast differentiation, proliferation and mineralization, as well as stimulatory effects on osteoclast precursors to enhance cellular adhesion. Taken together, these effects act to significantly increase bone turnover as measured by such markers as serum osteocalcin and bone-specific alkaline phosphatase and urinary N-telopeptide of type I collagen.…”

Pinctada fucata mantle gene 4 (PFMG4) from pearl oyster mantle enhances osteoblast differentiation

“…5) During the mineralization stage, the expression of proteins relative to mineralization is increased and these proteins are secreted into the ECM to promote calcium accumulation. 6) Ordinarily, this process takes about three weeks, and the first three days and the following ten days are regarded as proliferation stage and differentiation stage, respectively.…”

The Effects of Regular Tanning Bed Use and Increased Vitamin D Status on Serum Markers of Bone Turnover in Healthy Adult Women

“…35 In vitro studies of human osteoblast cultures show 1,25(OH) 2 D to be a strong inducer of osteocalcin production, but it has also been described that the 1,25(OH) 2 D-induced stimulation of osteocalcin decreases toward the mineralization stage because of concurrent accumulation of osteocalcin in the bone matrix. 5 This timing of mineralization phenomenon observed in cell culture research, may in part explain the disparate results on vitamin D status and circulating osteocalcin concentrations. The process of bone remodeling and turnover during adulthood is continuous and is characterized by two distinct phases: bone resorption which results in the disintegration and release of bone mineral and bone matrix fragments; and bone formation which follows resorption and involves the construction of matrix followed by its mineralization.…”

“…3,4 In vitro studies using osteoblast-like cells have demonstrated the effects of 1,25(OH) 2 D on mRNA, protein expression and enzyme activities; including effects on the regulation of collagen type I (major bone matrix protein), osteocalcin (most abundant noncollageneous bone matrix protein) and alkaline phosphatase activity (indicator of bone formation). 5 Although there is clear evidence that adequate vitamin D status has a positive effect on bone mineral density (BMD) in humans, [6][7][8] results from studies exploring the relationship between vitamin D status and measures specifi c to bone formation in humans are more ambiguous. Presumably this is because the mineral homeostasis effects of vitamin D are intertwined with any direct role the vitamin has on bone metabolism.…”

“…Presumably this is because the mineral homeostasis effects of vitamin D are intertwined with any direct role the vitamin has on bone metabolism. 5 Moreover, the majority of published reports exploring vitamin D status and biochemical markers of bone formation are limited to postmenopausal women and populations with compromised vitamin D status. [9][10][11][12][13] Circulating concentrations of 25-hydroxyvitamin D (25(OH)D), the standard measurement of vitamin D status, are typically higher in individuals with increased exposure to ultraviolet B (UVB) radiation due to the cutaneous production of vitamin D from its precursor, 7-dehydrocholesterol.…”