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Silicon and boron differ in their localization and loading in bone.

Jugdaohsingh R, Pedro LD, Watson A, Powell JJ - Bone Rep (2014)

Bottom Line: Silicon and boron share many similarities, both chemically and biochemically, including having similar effects on bone, although their mechanisms of action are not known.Here we compared the loading of silicon and boron into bone, their localization and how they are influenced by age (growth & development), to obtain further clues as to the biological effects of these elements and, especially, to see if they behave the same or not.Highest silicon and lowest boron concentrations were found in the under-mineralized bone of younger rats and lowest silicon and highest boron concentrations were found in the fully mineralized bone of the adult rat.

View Article: PubMed Central - PubMed

Affiliation: MRC Human Nutrition Research, Elsie Widdowson Laboratory, Cambridge, United Kingdom.

ABSTRACT

Silicon and boron share many similarities, both chemically and biochemically, including having similar effects on bone, although their mechanisms of action are not known. Here we compared the loading of silicon and boron into bone, their localization and how they are influenced by age (growth & development), to obtain further clues as to the biological effects of these elements and, especially, to see if they behave the same or not. Bone samples were obtained from two different studies where female Sprague Dawley rats had been maintained on a normal maintenance diet for up to 43 weeks. Total bone elemental levels were determined by ICP-OES following microwave assisted acid digestion. Silicon and boron levels in the decalcified bones (i.e. the collagen fraction) were also investigated. Silicon and boron showed marked differences in loading and in their localization in bone. Highest silicon and lowest boron concentrations were found in the under-mineralized bone of younger rats and lowest silicon and highest boron concentrations were found in the fully mineralized bone of the adult rat. Overall, however total bone silicon content increased with age, as did boron content, the latter mirroring the increase in calcium (mineral) content of bone. However, whereas silicon showed equal distribution in the collagen and mineral fractions of bone, boron was exclusively localized in the mineral fraction. These findings confirm the reported association between silicon and collagen, especially at the early stages of bone mineralization, and show that boron is associated with the bone mineral but not connective tissues. These data suggest that silicon and boron have different biological roles and that one is unlikely, therefore, to substitute for the other, or at least boron would not substitute for Si in the connective tissues. Finally, we noted that silicon levels in the mineral fraction varied greatly between the two studies, suggesting that one or more nutritional factor(s) may influence the loading of Si into the mineral fraction of bone. This and the nature of the interaction between Si and collagen deserve further attention.

No MeSH data available.


Related in: MedlinePlus

Study 1: Distribution of elements in the decalcified adult humerus bone from female Sprague Dawley rats, shown as a percentage of the total (i.e. whole) bone content. A high percentage of silicon was associated with the decalcified bone (i.e. collagen fraction). In contrast, boron was undetected in the decalcified bone. Insert graph shows the content (i.e. amount, in μg) of trace element in the decalcified bone. Data are means ± SD of five bones.
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f0005: Study 1: Distribution of elements in the decalcified adult humerus bone from female Sprague Dawley rats, shown as a percentage of the total (i.e. whole) bone content. A high percentage of silicon was associated with the decalcified bone (i.e. collagen fraction). In contrast, boron was undetected in the decalcified bone. Insert graph shows the content (i.e. amount, in μg) of trace element in the decalcified bone. Data are means ± SD of five bones.

Mentions: Silicon concentration of the paired decalcified humerus was 3.41 ± 1.01 μg/g wet weight (range: 2.39–4.62 μg/g wet weight) and accounted for 16 ± 5% (range: 11–23%) of the total bone Si content (Fig. 1). Boron was not detected (< 0.12 μg/g) in the decalcified bones. Indeed, of all the bone elements analyzed, the percentage retained in the decalcified bone (i.e. in the collagen fraction) was by far the greatest for Si (Fig. 1). The very low remaining percentage of Ca and P shows that even if the bone could not be totally demineralized, less than 1% mineral remained.


Silicon and boron differ in their localization and loading in bone.

Jugdaohsingh R, Pedro LD, Watson A, Powell JJ - Bone Rep (2014)

Study 1: Distribution of elements in the decalcified adult humerus bone from female Sprague Dawley rats, shown as a percentage of the total (i.e. whole) bone content. A high percentage of silicon was associated with the decalcified bone (i.e. collagen fraction). In contrast, boron was undetected in the decalcified bone. Insert graph shows the content (i.e. amount, in μg) of trace element in the decalcified bone. Data are means ± SD of five bones.
© Copyright Policy - CC BY-NC-ND
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4643752&req=5

f0005: Study 1: Distribution of elements in the decalcified adult humerus bone from female Sprague Dawley rats, shown as a percentage of the total (i.e. whole) bone content. A high percentage of silicon was associated with the decalcified bone (i.e. collagen fraction). In contrast, boron was undetected in the decalcified bone. Insert graph shows the content (i.e. amount, in μg) of trace element in the decalcified bone. Data are means ± SD of five bones.
Mentions: Silicon concentration of the paired decalcified humerus was 3.41 ± 1.01 μg/g wet weight (range: 2.39–4.62 μg/g wet weight) and accounted for 16 ± 5% (range: 11–23%) of the total bone Si content (Fig. 1). Boron was not detected (< 0.12 μg/g) in the decalcified bones. Indeed, of all the bone elements analyzed, the percentage retained in the decalcified bone (i.e. in the collagen fraction) was by far the greatest for Si (Fig. 1). The very low remaining percentage of Ca and P shows that even if the bone could not be totally demineralized, less than 1% mineral remained.

Bottom Line: Silicon and boron share many similarities, both chemically and biochemically, including having similar effects on bone, although their mechanisms of action are not known.Here we compared the loading of silicon and boron into bone, their localization and how they are influenced by age (growth & development), to obtain further clues as to the biological effects of these elements and, especially, to see if they behave the same or not.Highest silicon and lowest boron concentrations were found in the under-mineralized bone of younger rats and lowest silicon and highest boron concentrations were found in the fully mineralized bone of the adult rat.

View Article: PubMed Central - PubMed

Affiliation: MRC Human Nutrition Research, Elsie Widdowson Laboratory, Cambridge, United Kingdom.

ABSTRACT

Silicon and boron share many similarities, both chemically and biochemically, including having similar effects on bone, although their mechanisms of action are not known. Here we compared the loading of silicon and boron into bone, their localization and how they are influenced by age (growth & development), to obtain further clues as to the biological effects of these elements and, especially, to see if they behave the same or not. Bone samples were obtained from two different studies where female Sprague Dawley rats had been maintained on a normal maintenance diet for up to 43 weeks. Total bone elemental levels were determined by ICP-OES following microwave assisted acid digestion. Silicon and boron levels in the decalcified bones (i.e. the collagen fraction) were also investigated. Silicon and boron showed marked differences in loading and in their localization in bone. Highest silicon and lowest boron concentrations were found in the under-mineralized bone of younger rats and lowest silicon and highest boron concentrations were found in the fully mineralized bone of the adult rat. Overall, however total bone silicon content increased with age, as did boron content, the latter mirroring the increase in calcium (mineral) content of bone. However, whereas silicon showed equal distribution in the collagen and mineral fractions of bone, boron was exclusively localized in the mineral fraction. These findings confirm the reported association between silicon and collagen, especially at the early stages of bone mineralization, and show that boron is associated with the bone mineral but not connective tissues. These data suggest that silicon and boron have different biological roles and that one is unlikely, therefore, to substitute for the other, or at least boron would not substitute for Si in the connective tissues. Finally, we noted that silicon levels in the mineral fraction varied greatly between the two studies, suggesting that one or more nutritional factor(s) may influence the loading of Si into the mineral fraction of bone. This and the nature of the interaction between Si and collagen deserve further attention.

No MeSH data available.


Related in: MedlinePlus