Effect of Xylo-Oligosaccharides Supplementation by Drinking Water on the Bone Properties and Related Calcium Transporters in Growing Mice

Abstract

Xylo-oligosaccharides (XOS), non-digestible oligosaccharides, have the potential to regulate intestinal microorganisms, and thus, improve host health, but little evidence exists for the prebiotic effects on bone health. This study evaluates the dose-response effect of XOS supplementation on bone properties, the morphology of the intestine, cecum pH, and cecum wall weight, as well as the related calcium transporters. Ninety-six 28-day-old male mice were randomized into one of four groups, fed the same commercial diet, and given different types of deionized water containing 0, 1, 2, or 4% XOS by concentration for 30 days. Eight mice were randomly selected to accomplish particular tasks every 10 days. No significant differences in serum Ca and P levels and growth performance were observed among the four studied groups. XOS intervention significantly decreased cecum pH and increased cecum wall weight in a dose-dependent manner. At the late growth stage, compared with 0% XOS, the bone mineral density (BMD) and bone-breaking strength in 4% XOS were significantly higher. The bone crystallinity with 4% XOS, measured by Raman spectrum, was significantly enhanced compared to that with 0% XOS during later growth. The villus height and villus height to crypt depth (VH:CD) were enhanced with an increase of XOS concentration during the later stage of growth. The expression of transient receptor potential vanillin receptor 6 (TRPV6) and Na+/Ca2+ exchanger 1 (NCX1) in the duodenum were enhanced by XOS supplementation. XOS exerted a positive influence on bone properties by decreasing the cecum pH, increasing the cecum wall and villus structure, and upregulating the expression of related calcium transporters.

Effects of Calcium Source, Inulin, and Lactose on Gut‐Bone Associations in an Ovarierectomized Rat Model

“…The finding is consistent with a former study who also observed an increased Trpv6 level in the duodenum of mice after xylo‐oligosaccharides intervention. [ 9 ] A possible mechanism is that SCFAs in cecum stimulate the expression of Trpv6. [ 9 ] In addition, inulin also enhanced the expression of Aqp8, which is a channel regulating water absorption.…”

“…[ 9 ] A possible mechanism is that SCFAs in cecum stimulate the expression of Trpv6. [ 9 ] In addition, inulin also enhanced the expression of Aqp8, which is a channel regulating water absorption. Enhanced water absorption across GI tract may accelerate passive calcium absorption by concentrating Ca 2+ in intestinal lumen.…”

“…Thus, it has been shown that SCFAs could promote the synthesis of CaBP and TRPV6, two channels for calcium absorption in intestinal epithelial cells. [ 8 , 9 ] In addition, an altered gut microbiota composition as a result of inulin supplementation may also contribute to attenuated bone loss as seen in OVX rats. [ 10 ] A possible mechanism involves the effect of some bacteria (e.g., Bifidobacterium and Lactobacillus ) on the prevention of inflammation and lower T cells and proinflammatory markers.…”

Role of Dietary Supplements and Probiotics in Modulating Microbiota and Bone Health: The Gut-Bone Axis

“…XOSs are prebiotics composed of 2–7 xylose molecules fostering Bifidobacteria over Lactobacillus [ 63 ]; in mice, they increase calcium uptake by upregulating the expression of transient receptor potential vanillin receptor 6 (TRPV6) and Na + /Ca 2+ exchanger in the duodenum, and increase BMD [ 64 ]; they also reduce bone loss in high-fat-diet insulin-resistant mice [ 65 ], and decrease inflammation markers.…”

“Osteomicrobiology”: The Nexus Between Bone and Bugs

“…Prebiotics also enhance bone mass by decreasing intestinal permeability and thus preventing systemic inflammation ( Zhang et al, 2021 ). Xylo-oligosaccharides (XOS) treatment was observed to increase BMD by upregulating the expression of Ca transporters in the intestine ( Gao and Zhou, 2020 ). It is reported that FOS also enhances osteogenesis and thus induces bone formation.…”