In Vitro Screening of Trehalose Synbiotics and Their Effects on Early-Lactating Females and Offspring Mice

Abstract

Activities such as childbirth and breastfeeding can cause severe oxidative stress and inflammatory damage to the mother during early lactation, and can affect animal milk production, and the growth and development of offspring. Trehalose alleviates damage to the body by endowing it with stress resistance. In this study, we used trehalose combined with Lactobacillus plantarum, Bifidobacterium longum, Bacillus subtilis, and Saccharomyces cerevisiae to explore whether dietary intervention can alleviate oxidative stress and inflammatory damage in early lactation and to evaluate the growth ability, acid production ability, antioxidant ability, non-specific adhesion ability, antibacterial ability, and other parameters to determine the optimal combinations and proportions. The results showed that the synbiotics composed of 2.5% trehalose and 1 × 10⁷ cfu/g of Bifidobacterium longum could regulate the gut microbiota, and promote mammary gland development in dams by reducing progesterone (PROG) content in the blood, increasing prolactin (PRL) and insulin-like growth factor-1 (IGF-1) content, enhancing their antioxidant and immune abilities, and effectively increasing the weight and lactation of early lactating dams. In addition, it can also affect the growth of offspring and the development of the intestinal barrier. These results indicate that trehalose synbiotics have great potential in alleviating oxidative stress and inflammatory damage in early lactation.

Keywords: early-lactating; mice; oxidative stress; synbiotics; trehalose.

Figure 1

Growth characteristics of different probiotics fermented with prebiotics. (A) Growth curve and (B) pH profile. The Lactobacillus plantarum group, Bifidobacterium longum group, Saccharomyces cerevisiae group, and Bacillus subtilis group represent different combinations of synbiotics synthesized by Lactobacillus plantarum, Bifidobacterium longum, Saccharomyces cerevisiae, and Bacillus subtilis with trehalose, respectively.

Figure 2

The antioxidant capacity of different strains utilizing trehalose. (A) DPPH radical scavenging rate (%); (B) hydroxyl radical scavenging ability (%); and (C) total restoration capacity (μmol/mL). IC is a complete cell, while CFE is a cell-free extract. Different lowercase letters marked in the figure indicate significant differences (p < 0.05).

Figure 3

The effect of trehalose synbiotics on postpartum performance of dams and offspring. (A) Experimental set-up: In the early stage of lactation (0–7 days after delivery), the dams in the Con group were given a basal diet, and the dams in the TB group were supplemented with trehalose synbiotics on the basis of the basal diet. All rats were euthanized on day 8 after delivery. (B) Body weight changes of dams; (C) body weight changes of offspring; (D) food intake; and (E) milk production. * p < 0.05; ** p < 0.01.

Figure 4

The effects of trehalose synbiotics on the development and antioxidant activity in the maternal mammary gland. (A) Representative histologic staining of mammary glands collected from dams. (Original magnification, 20-fold). Scale bars represent 50 μm. (B) The expression levels of antioxidant genes (Nqo1, Prdx1, Nrf2, and SOD) in the mammary glands of dams. (C) The expression levels of development genes (Prolactin, Whey acidic protein, and β-casein) in the mammary glands of dams. ** p < 0.01; **** p < 0.0001.

Figure 5

Effects of trehalose synbiotics on gut microbiota in the dam. (A) Rarefaction curve. (B) PCoA analysis chart. PC1 and PC2 explained variation; the dots represent each sample. (C) Venn diagrams showing the OTUs in the two groups: Con, normal control, and TB, trehalose synbiotics. The Con group contained 441 OTUs, the TB group contained 287 OTUs, and there were 503 OTUs in both groups. (D) Ace index. (E) Shannon index. (F) Chao index. (G,H) Relative abundance of the gut bacterial composition at the level of the phylum and Genus. (I,J) The relative abundance of gut microbiota at the phylum and species levels. (I,J) Analysis of differences in dominant microbial communities among groups at the phylum and family levels, with the microbial community ranking among the top eight in relative abundance. * p < 0.05; ** p < 0.01.

Figure 6

Heatmaps of Spearman correlation analyses. The depth of colour indicates the relative abundance of the top 20 dominant bacterial genera and their correlation with postpartum performance, immunity, and antioxidant activity in dams, with red indicating a positive correlation and blue indicating a negative correlation. MDA: malondialdehyde; TNF-α: tumor necrosis factor-α; WG: body weight changes of dams; IL-6: interleukin-6; IL-1β: interleukin-1β; E2: oestrogen; VFI: food intake; CAT: catalase; IgG: immunoglobulin G; INS: insulin; IGF-1: insulin-like growth factor 1; M: milk production; IL-10: interleukin-10; IgA: immunoglobulin A; SOD: superoxide dismutase; PROG: progesterone; SWG: body weight changes of offspring; GSH-Px: glutathione peroxidase; IgM: immunoglobulin M; PRL: prolactin. * p < 0.05; ** p < 0.01; *** p < 0.001.

Figure 7

The effects of trehalose synbiotics on the intestinal tract of offspring. (A) Representative histologic staining of ileal tissue collected from offspring. (Original magnification, 10-fold). Scale bars represent 100 μm. (B) Crypt depth in the ileum of offspring. (C) Villus length in the ileum of offspring. (D) The villus length-to-crypt depth ratio in the ileum of offspring. (E) The number of goblet cells in the ileum of offspring. * p < 0.05.