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Dietary Silicon Deficiency Does Not Exacerbate Diet-Induced Fatty Lesions in Female ApoE Knockout Mice.

Jugdaohsingh R, Kessler K, Messner B, Stoiber M, Pedro LD, Schima H, Laufer G, Powell JJ, Bernhard D - J. Nutr. (2015)

Bottom Line: The serum silicon concentration in the -Si group was significantly lower than in the +Si-feed (by up to 78%; P < 0.003) and the +Si-water (by up to 84%; P < 0.006) groups.The aorta silicon concentration was also lower in the -Si group than in the +Si-feed group (by 65%; P = 0.025), but not compared with the +Si-water group.There were no differences in serum and aorta silicon concentrations between the silicon-replete groups.

View Article: PubMed Central - PubMed

Affiliation: Medical Research Council (MRC) Human Nutrition Research, Elsie Widdowson Laboratory, Cambridge, United Kingdom; ravin.jugdaohsingh@mrc-hnr.cam.ac.uk.

ABSTRACT

Background: Dietary silicon has been positively linked with vascular health and protection against atherosclerotic plaque formation, but the mechanism of action is unclear.

Objectives: We investigated the effect of dietary silicon on 1) serum and aorta silicon concentrations, 2) the development of aortic lesions and serum lipid concentrations, and 3) the structural and biomechanic properties of the aorta.

Methods: Two studies, of the same design, were conducted to address the above objectives. Female mice, lacking the apolipoprotein E (apoE) gene, and therefore susceptible to atherosclerosis, were separated into 3 groups of 10-15 mice, each exposed to a high-fat diet (21% wt milk fat and 1.5% wt cholesterol) but with differing concentrations of dietary silicon, namely: silicon-deprived (-Si; <3-μg silicon/g feed), silicon-replete in feed (+Si-feed; 100-μg silicon/g feed), and silicon-replete in drinking water (+Si-water; 115-μg silicon/mL) for 15-19 wk. Silicon supplementation was in the form of sodium metasilicate (feed) or monomethylsilanetriol (drinking water).

Results: The serum silicon concentration in the -Si group was significantly lower than in the +Si-feed (by up to 78%; P < 0.003) and the +Si-water (by up to 84%; P < 0.006) groups. The aorta silicon concentration was also lower in the -Si group than in the +Si-feed group (by 65%; P = 0.025), but not compared with the +Si-water group. There were no differences in serum and aorta silicon concentrations between the silicon-replete groups. Body weights, tissue wet weights at necropsy, and structural, biomechanic, and morphologic properties of the aorta were not affected by dietary silicon; nor were the development of fatty lesions and serum lipid concentrations.

Conclusions: These findings suggest that dietary silicon has no effect on atherosclerosis development and vascular health in the apoE mouse model of diet-induced atherosclerosis, contrary to the reported findings in the cholesterol-fed rabbit model.

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Related in: MedlinePlus

Tensile strength (A), stiffness (B), and initial ring circumference (C) of the aorta of female apoE knockout mice in Study 2 fed a diet high in butter fat and depleted in silicon, compared with mice fed the 2 silicon-replete, high-fat diets: silicon was replete in the feed or the drinking water. Values are shown for each of the 7 aortic rings/positions from each mouse. Values are means ± SDs; n = 10–15 mice/position/group. Stiffness (B) and initial ring circumference (C) profiles were similar for the 3 dietary silicon groups. −Si, silicon-deprived; +Si-feed, silicon-replete in feed; +Si-water, silicon-replete in drinking water.
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fig5: Tensile strength (A), stiffness (B), and initial ring circumference (C) of the aorta of female apoE knockout mice in Study 2 fed a diet high in butter fat and depleted in silicon, compared with mice fed the 2 silicon-replete, high-fat diets: silicon was replete in the feed or the drinking water. Values are shown for each of the 7 aortic rings/positions from each mouse. Values are means ± SDs; n = 10–15 mice/position/group. Stiffness (B) and initial ring circumference (C) profiles were similar for the 3 dietary silicon groups. −Si, silicon-deprived; +Si-feed, silicon-replete in feed; +Si-water, silicon-replete in drinking water.

Mentions: From the tensile measurements in Study 2, the forces required to rupture the aortic wall were determined for the different dietary silicon groups. Maximum tear force increased when moving down the descending aorta, peaking at position 5 or 6 with a reduction at position 7 (Figure 5A). The pattern was comparable between the −Si and +Si-feed groups, but a significant difference was found between −Si and +Si-water groups (P = 0.010), suggesting less force was required to rupture the aortic wall in the +Si-water group. There was no difference in maximum tear force between +Si groups.


Dietary Silicon Deficiency Does Not Exacerbate Diet-Induced Fatty Lesions in Female ApoE Knockout Mice.

Jugdaohsingh R, Kessler K, Messner B, Stoiber M, Pedro LD, Schima H, Laufer G, Powell JJ, Bernhard D - J. Nutr. (2015)

Tensile strength (A), stiffness (B), and initial ring circumference (C) of the aorta of female apoE knockout mice in Study 2 fed a diet high in butter fat and depleted in silicon, compared with mice fed the 2 silicon-replete, high-fat diets: silicon was replete in the feed or the drinking water. Values are shown for each of the 7 aortic rings/positions from each mouse. Values are means ± SDs; n = 10–15 mice/position/group. Stiffness (B) and initial ring circumference (C) profiles were similar for the 3 dietary silicon groups. −Si, silicon-deprived; +Si-feed, silicon-replete in feed; +Si-water, silicon-replete in drinking water.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4478943&req=5

fig5: Tensile strength (A), stiffness (B), and initial ring circumference (C) of the aorta of female apoE knockout mice in Study 2 fed a diet high in butter fat and depleted in silicon, compared with mice fed the 2 silicon-replete, high-fat diets: silicon was replete in the feed or the drinking water. Values are shown for each of the 7 aortic rings/positions from each mouse. Values are means ± SDs; n = 10–15 mice/position/group. Stiffness (B) and initial ring circumference (C) profiles were similar for the 3 dietary silicon groups. −Si, silicon-deprived; +Si-feed, silicon-replete in feed; +Si-water, silicon-replete in drinking water.
Mentions: From the tensile measurements in Study 2, the forces required to rupture the aortic wall were determined for the different dietary silicon groups. Maximum tear force increased when moving down the descending aorta, peaking at position 5 or 6 with a reduction at position 7 (Figure 5A). The pattern was comparable between the −Si and +Si-feed groups, but a significant difference was found between −Si and +Si-water groups (P = 0.010), suggesting less force was required to rupture the aortic wall in the +Si-water group. There was no difference in maximum tear force between +Si groups.

Bottom Line: The serum silicon concentration in the -Si group was significantly lower than in the +Si-feed (by up to 78%; P < 0.003) and the +Si-water (by up to 84%; P < 0.006) groups.The aorta silicon concentration was also lower in the -Si group than in the +Si-feed group (by 65%; P = 0.025), but not compared with the +Si-water group.There were no differences in serum and aorta silicon concentrations between the silicon-replete groups.

View Article: PubMed Central - PubMed

Affiliation: Medical Research Council (MRC) Human Nutrition Research, Elsie Widdowson Laboratory, Cambridge, United Kingdom; ravin.jugdaohsingh@mrc-hnr.cam.ac.uk.

ABSTRACT

Background: Dietary silicon has been positively linked with vascular health and protection against atherosclerotic plaque formation, but the mechanism of action is unclear.

Objectives: We investigated the effect of dietary silicon on 1) serum and aorta silicon concentrations, 2) the development of aortic lesions and serum lipid concentrations, and 3) the structural and biomechanic properties of the aorta.

Methods: Two studies, of the same design, were conducted to address the above objectives. Female mice, lacking the apolipoprotein E (apoE) gene, and therefore susceptible to atherosclerosis, were separated into 3 groups of 10-15 mice, each exposed to a high-fat diet (21% wt milk fat and 1.5% wt cholesterol) but with differing concentrations of dietary silicon, namely: silicon-deprived (-Si; <3-μg silicon/g feed), silicon-replete in feed (+Si-feed; 100-μg silicon/g feed), and silicon-replete in drinking water (+Si-water; 115-μg silicon/mL) for 15-19 wk. Silicon supplementation was in the form of sodium metasilicate (feed) or monomethylsilanetriol (drinking water).

Results: The serum silicon concentration in the -Si group was significantly lower than in the +Si-feed (by up to 78%; P < 0.003) and the +Si-water (by up to 84%; P < 0.006) groups. The aorta silicon concentration was also lower in the -Si group than in the +Si-feed group (by 65%; P = 0.025), but not compared with the +Si-water group. There were no differences in serum and aorta silicon concentrations between the silicon-replete groups. Body weights, tissue wet weights at necropsy, and structural, biomechanic, and morphologic properties of the aorta were not affected by dietary silicon; nor were the development of fatty lesions and serum lipid concentrations.

Conclusions: These findings suggest that dietary silicon has no effect on atherosclerosis development and vascular health in the apoE mouse model of diet-induced atherosclerosis, contrary to the reported findings in the cholesterol-fed rabbit model.

Show MeSH
Related in: MedlinePlus