Effect of Silicon Supplementation in Diets with Different Calcium Levels on Bone Mineral Metabolism and Bone Status in Growing Female Rats

Abstract

Abstract Objectives Silicon is important for the growth and development of bone and connective tissues. However, few studies have investigated effects of silicon supplementation on bone metabolism on growing females. We evaluated the effect of silicon supplementation on bone mineral metabolism and bone status in growing female rats fed diet with different calcium levels. Methods Sixty 6-wk-old Sprague-Dawley female rats were divided into 6 groups and fed diet with different levels of calcium (0.1%, 0.5%, 1.5%) and silicon (5 ppm, 500 ppm) for 10 weeks. We used a two-way ANOVA test to examine the difference and a significant level was set at P < 0.05. Results Silicon retention significantly increased by silicon supplementation and significantly decreased by high calcium diet (1.5%). Mg retention significantly decreased by high calcium diet. Serum calcium and silicon contents were not significantly different among the 6 groups. Low calcium diet (0.1% calcium) significantly increased serum osteocalcin and C-telopeptide cross-links of type I collagen (CTX) levels, and silicon supplementation significantly decreased CTX levels in the low calcium diet group. Bone mineral density was significantly increased along with greater calcium level in the diet, but was decreased by silicon supplementation in the high calcium diet. Rats in the 0.5% calcium diet group had significant increase in strength of the tibia by silicon supplementation. Conclusions According to our findings, the effect of silicon supplementation on bone metabolism may differ according to the calcium intake levels in growing females. Although further research is needed, when supplementing silicon to improve bone health in growing females, the calcium intake level should be considered. Funding Sources Korea Research Foundation.