Effects of soluble silicon compound and deep-sea water on biochemical and mechanical properties of bone and the related gene expression in mice

Abstract

Silicon has been known as an essential element for bone formation. The silicon contents of sea water increase with increasing of depth: 1.8 ppm Si in deep-sea water (DW) at 612 m in depth versus 0.06 ppm in surface sea water (SW). The effects of soluble silicon (Si) and DW from which NaCl was eliminated were studied in comparison with tap water (TW) and SW in cell cultures and in animal experiments using the control strain of senescence accelerated mouse, SAMR1. Si at 10 ppm as sodium metasilicate or 10% DW in the alpha-MEM medium stimulated cellular viability, marker enzymes of osteoblast and osteoclast cell lines, and the (45)CaCl(2) uptake in those cells in comparison with the medium control. After weanling SAMR1 were maintained for 6 months on a diet containing 200 ppm Si and 39% of DW and SW, DW and Si improved bone biochemical indices such as femoral weight, mineral and collagen content, and marker enzymes of bone formation and resorption as well as mechanical properties as compared to TW. In the femoral bone marrow of SAMR1, the mRNA expression of bone morphogenetic protein-2 (BMP-2), interleukin-11 (IL-11), and runt-related transcription factor 2 (Runx 2), which stimulate osteoblast development as well as type I procollagen (COL1A1) mRNA, were significantly increased in both DW and Si groups. The expressions of both osteoprotegerin (OPG) and receptor activator of NF-kappaB ligand (RANKL) were also elevated, resulting in distinct increases of the OPG/RANKL ratio in both DW and Si groups. The results indicated that a soluble silicate and deep-sea water as its natural material stimulated cell growth in both osteoblasts and osteoclasts in cell culture and promoted bone metabolic turnover in favor of bone formation through stimulation of the related mRNA expression in animal experiments.

Effects of thirty elements on bone metabolism

“…Although questioned by some researchers [241], the implication of silicon in bone health has been confirmed with additional, more recent studies, which report animals deprived of silicon present with skeletal disorders, reduced collagen synthesis, and reduced osteopontin-related proteins [242][243][244][245]. Conversely, adequate silicon intake or supplementation has been shown to stimulate collagen secretion, enhance bone matrix mineralization and bone mineral density, and decrease bone resorption [246][247][248]. Silicon is even thought to have beneficial roles in prevention of osteoporosis.…”

Molecular Characterization of a Nonfibrillar Collagen from the Marine Sponge Chondrosia reniformis Nardo 1847 and Positive Effects of Soluble Silicates on Its Expression

“…Indeed, it is widely known that silicon compounds play a key role in the production of collagen in many living beings, from sponges (Krasko et al 2000) to vertebrates (Carlisle 1972(Carlisle , 1980Maehira et al 2008), but to our knowledge, there are no strong evidences yet for a direct role of these compounds in the regulation of gene expression. Accordingly, identification and characterization of COLch, together with the evidence of upregulation of its expression by soluble silicon compounds in C. reniformis fragmorphs, seems to be a valuable step to establish a model for the sustainable production of this biomaterial and for studies of the molecular mechanisms of biosynthesis of extracellular matrix protein in the evolution of animal kingdom.…”

Characterization and osteogenic activity of a silicatein/biosilica-coated chitosan-graft-polycaprolactone

“…Interestingly, however, at all times the coating slightly enhanced the viability of the SaOS-2 cells when compared to the control (cells grown on tissue culture plates). This effect might be caused by the release of silicate from the biosilica coating, which might stimulate the cell metabolism and thus the enzymatic conversion of MTT [47].…”