Prematurely delivering mothers show reductions of lachnospiraceae in their gut microbiomes

Relationship between gastrointestinal disturbances, blood lipid levels, inflammatory markers, and preterm birth

BACKGROUND

The challenging incidence of preterm birth, the underlying causes of preterm birth remain unclear. This study determined the relationship between disturbed gastrointestinal symptoms, inflammatory markers, blood lipid levels, and preterm birth.

METHOD

One hundred and twenty pregnant women with preterm labour were compared to 120 pregnant women with full-term deliveries. All subjects underwent lactose breath and serologic testing. The correlation between small intestinal bacterial overgrowth (SIBO)-positivity, gastrointestinal symptoms, inflammatory factors, and blood lipid metabolism and preterm birth was analysed using the Spearman method.

RESULTS

SIBO, hydrogen, and methane levels were significantly higher in the preterm birth (PTB) group than the full-term birth (FTB) group at different time points (P < 0.05); Levels of high-sensitivity C-reactive protein (hs-CRP) (3.95[2.70-5.77] vs. 2.47[1.45-3.83]), Interleukin (IL)-10 (3.05[2.27-4.33] vs. 2.09[1.04-3.47]), IL-6 (5.23[3.95-8.50] vs. 2.98[2.22-4.44]), tumour necrosis factor -alpha (TNF-α) (3.23[1.55-4.90] vs. 1.76[0.98-3.10]), total cholesterol (TC) (5.52[4.97-5.95] vs. 5.24[4.73-5.85]), and triglycerides (TG) (2.58[2.04-3.53] vs. 2.24[1.59-3.05]) were significantly higher in the PTB group than the FTB group (P < 0.05). Abdominal distension (2.67[1.67-3.00] vs. 2.33[1.67-2.67]) and constipation (2.00[1.33-2.00] vs. 1.67[1.33-2.00]) scores were also markedly higher in the PTB group than the FTB group (P < 0.05). Preterm birth was positively correlated with SIBO, TC, and TG levels. Additionally, SIBO was positively correlated with hs-CRP, IL-10, IL-6, and TNF-α levels, abdominal distension, and constipation (P < 0.05). Logistic regression analysis found the close association between positive SIBO, biochemistry indicators and preterm birth.

CONCLUSION

Gastrointestinal disturbances, hyperlipidaemia and SIBO-positivity are more likely to occur among pregnant women with preterm labour. Further research with a large sample size in multi-centers is needed to validate the results.

Effects of Spent Substrate of Oyster Mushroom (Pleurotus ostreatus) on Feed Utilization and Liver Serum Indices of Hu Sheep from the Perspective of Duodenal Microorganisms

This study aimed to evaluate the effects of Pleurotus ostreatus spent mushroom substrate (P.SMS), which is characterized by high production but low utilization, on feed utilization and liver serum indices from the perspective of duodenal microorganisms. Forty-five 3-month-old Hu sheep were randomly assigned to five groups and fed diets in which whole-plant corn silage (WPCS) was substituted with P.SMS at levels of 0% (Con), 5% (PSMS5), 10% (PSMS10), 15% (PSMS15), or 20% (PSMS20). The results indicated that the addition of P.SMS complexly influenced the apparent digestibility of dry matter, organic matter, and crude protein, with PSMS10 showing the highest digestibility of these nutrients. P.SMS inclusion significantly affected serum alanine aminotransferase levels, with PSMS5 showing higher levels than both the Con and PSMS20 groups (p < 0.05). Importantly, the inclusion of P.SMS did not affect the richness and diversity of duodenal microorganisms. Significant differences in the phyla Verrucomicrobiota and Spirochaetota were observed between the Con and PSMS20 groups. The observed trend towards an increase in the genus Trichoderma (p = 0.057) suggests that P.SMS is susceptible to contamination by this genus, which in turn affects the structure of the intestinal flora. Furthermore, functional gene predictions indicated differences in amino acid metabolism among the groups (p < 0.05). In conclusion, feeding with 10% P.SMS resulted in the highest digestibility without adversely affecting the structure of the duodenal community or liver function.

Amniotic fluid proteomic analysis identifies IL1RL1, APOE, and NECTIN4 as new biomarkers for preterm birth

BACKGROUND

Despite extensive research, the identification of effective biomarkers for early prediction of preterm birth (PTB) continues to be a challenging endeavor. This study aims to identify amniotic fluid (AF) protein biomarkers useful for the early diagnosis of PTB.

METHODS

We initially identified the protein expression profiles in the AF of women with PTB (n = 22) and full-term birth (FTB, n = 22), from the First People's Hospital of Yunnan Province who underwent amniocentesis from November 2019 to February 2020, using mass spectrometry employing the data-independent acquisition (DIA) technique, and then analyzed differentially expressed proteins (DEPs). Subsequently, the least absolute shrinkage and selection operator (LASSO) and random forest analysis were employed to further screen the key proteins for PTB biomarker identification. The receiver operating characteristic (ROC) analysis, calibration plots, and decision curve analyses (DCA) were utilized to assess the discrimination and calibration of the key biomarkers.

RESULTS

A total of 25 DEPs were identified between the PTB and FTB groups, comprising 13 up-regulated and 12 down-regulated proteins. Three key protein biomarkers for early PTB diagnosis were identified: IL1RL1 (interleukin-1 receptor-like 1), APOE (apolipoprotein E), and NECTIN4 (nectin cell adhesion molecule 4). The results of the ROC analysis showed that the area under the curve (AUC) of the three proteins combined as a biomarker for early diagnosis of PTB was 0.913 (95% CI: 0.823-1.000), with a sensitivity of 0.864 and a specificity of 0.955, both superior to those of the individual biomarkers. Bootstrap internal validation revealed a concordance index (C-index) of 0.878, with a sensitivity of 0.812 and a specificity of 0.773, indicating the robust predictive performance of these biomarkers.

CONCLUSIONS

We identified three previously unexplored yet potentially useful protein biomarkers in AF for early PTB diagnosis: IL1RL1, APOE, and NECTIN4.

The maternal gut microbiome in pregnancy: implications for the developing immune system

The gut microbiome has important roles in host metabolism and immunity, and microbial dysbiosis affects human physiology and health. Maternal immunity and microbial metabolites during pregnancy, microbial transfer during birth, and transfer of immune factors, microorganisms and metabolites via breastfeeding provide critical sources of early-life microbial and immune training, with important consequences for human health. Only a few studies have directly examined the interactions between the gut microbiome and the immune system during pregnancy, and the subsequent effect on offspring development. In this Review, we aim to describe how the maternal microbiome shapes overall pregnancy-associated maternal, fetal and early neonatal immune systems, focusing on the existing evidence and highlighting current gaps to promote further research.