Vasorin-deficient mice display disturbed vitamin D and mineral homeostasis in combination with a low bone mass phenotype.

Vasorin (Vasn) is a pleiotropic molecule involved in various physiological and pathological conditions, including cancer. Vasn has also been detected in bone cells of developing skeletal tissues but no function for Vasn in bone metabolism has been implicated yet. Therefore, this study aimed to investigate if Vasn plays a significant role in bone biology.

Organic phosphate but not inorganic phosphate regulates expression through MAPK and TGF-ꞵ signaling.

One of the main regulators of phosphate homeostasis is fibroblast growth factor 23 (FGF23), secreted by osteocytes. The effects of organic versus inorganic dietary phosphate on this homeostasis are unclear. This study used MC3T3-E1 FGF23-producing cells to examine the transcriptomic responses to these phosphates.

A role for sirtuin 1 in FGF23 activation following β-glycerophosphate treatment.

Phosphate homeostasis is vital for many biological processes and disruptions in circulating levels can be detrimental. While the mechanisms behind FGF23 regulation have been regularly studied, the role of extracellular phosphate sensing and its impact on fibroblast growth factor 23 (FGF23) expression remains unclear. This study aimed to investigate the involvement of reactive oxygen species (ROS), silent information regulator 1 (SIRT1), and Hairy and Enhancer of Split-1 (HES1) in regulating FGF23 in FGF23 expressing MC3T3-E1 cells.

In vitro regulation of fibroblast growth factor 23 by 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D synthesized by osteocyte-like MC3T3-E1 cells.

Fibroblast growth factor 23 (FGF23) is produced and secreted by osteocytes and is essential for maintaining phosphate homeostasis. One of the main regulators of FGF23, 1,25-dihydroxyvitamin D (1,25(OH)2D3), is primarily synthesized in the kidney from 25-hydroxyvitamin D (25(OH)D) by 1α-hydroxylase (encoded by CYP27B1). Hitherto, it is unclear whether osteocytes can convert 25(OH)D and thereby allow for 1,25(OH)2D3 to induce FGF23 production and secretion locally.