Administration of xylo‐oligosaccharides improves depressive‐like behaviour in mice caused by chronic unpredictable mild stress by altering microbiota composition

Abstract

Summary Xylo‐oligosaccharides (XOS) is a functional oligosaccharide with prebiotic properties, and could be fermented by gut microbiota. In this study, the modulatory effects of XOS on emotions and behaviours at different dose were investigated based on the mouse model of chronic unpredictable mild stress‐induced depression. The result showed that 0.23 and 0.50 g kg−1 doses of XOS significantly increased sucrose preference index and decreased the immobility time in tail suspension and forced swimming tests. Meanwhile, the dose of 0.23 g kg−1 day−1 XOS significantly increased the concentration of neurotransmitters, such as 5‐hydroxytryptamine and γ‐ aminobutyric acid. Furthermore, the analysis of the faecal microbiota with XOS intervention showed a higher relative abundance of Akkermansia, Bifidobacterium and Lactobacillus, fewer Desulfovibrio and the SCFA concentrations increased with XOS prevention treatment. These results suggested that the dietary supplementation XOS could improve chronic stress‐induced depressive‐like behaviour by modulating neurotransmitters and reverting gut microbiota changes in mice. These findings present XOS as a potential prebiotic targeting to the gut microbiota for mood disorders.

Lipid‐lowering activity and underlying mechanism of glycosylated peptide–calcium chelate prepared by transglutaminase pathway

“…Therefore, we first studied whether the CSPHs‐Ca modified with XOS could also have a prebiotic effect to help the body improve the structure of intestinal microbiota. As XOS is a good Bifidobacterium factor (Shu et al., 2022), compared to other treatment groups, probiotics (B. adolescentis and L. acidophilus) had the highest OD 600 when fermented with XOS as the carbon source, in particular, B. adolescentis reached high cell density (OD 600 > 1.4) during 24‐h culture, indicating that XOS could be well utilized by B. adolescentis and L. acidophilus (Zhang et al., 2019) (Figure 1a,b). Similarly, in the XOS‐CSPHs‐Ca‐TG treatment group, the maximum growth rate (slope of the curve) of B. adolescentis and L. acidophilus was close to that of XOS, and it enabled B. adolescentis and L. acidophilus to enter the logarithmic growth phase 2–4 h earlier than in the control and CSPHs‐Ca groups, and an OD 600 exceeding 1.0 was obtained at the end of the growth curve (Figure 1a,b).…”

“…Consistently, Li (2021) also found that after 24 h of cultivation with Tremella fuciformis polysaccharides, Bifidobacterium and Lactobacillus could enter a logarithmic growth phase at 6 h, and the OD 600 at the endpoint of the curve could reach 1.0. However, its cell density is lower than that of XOS and XOS‐CSPHs‐Ca‐TG, which may be attributed to bifidogenic function of XOS is 10–20 times that of other polysaccharides (Shu et al., 2022). These results indicated that glycosylated peptide–calcium chelate could promote the growth of beneficial microorganisms in the intestinal tract and give full play to the benefit of prebiotics.…”

“…The SCFA produced by gut bacteria, mainly acetic acid, propionic acid, and butyric acid, is used as an energy source for colon cells and a substrate for liver metabolic pathways (Zhang et al., 2021). XOS is a widely recognized prebiotic, which is a potent substrate for acetic acid and butyric acid (Shu et al., 2022). As expected, after the addition of XOS, the total SCFAs concentration significantly increased, with acetic acid and butyric acid concentrations increasing by 2.46 and 2.008 mM/g, respectively, compared to the control group ( p < .05) (Figure 2a,c).…”