Pingping Jiang

BACKGROUND: Metabolic and neurovascular disturbances contribute to brain injury after birth asphyxia. We previously showed that plasma feeding attenuated neuropathology after transient umbilical cord occlusion in piglets. This study explored the metabolic and molecular consequences of birth asphyxia and whether plasma feeding preserves metabolic homeostasis and brain barrier integrity. METHODS: Piglets (n=89) delivered by cesarean section on gestational day 113 underwent umbilical cord occlusion (asphyxia [ASP]) or remained nonasphyxiated (control [CON]). ASP and CON piglets were randomly assigned to receive formula reconstituted with either water (vehicle-treated group) or sow plasma (plasma-treated group). Animals were euthanized at 1 hour, 24 hours, or day 4 after insult. Cerebrospinal fluid metabolites were profiled by untargeted liquid chromatography–mass spectrometry metabolomics at 24 hours. Expression of metabolite transporters and structural components of the blood-brain barrier in the caudate nucleus and the blood–cerebrospinal fluid barrier at the choroid plexus was assessed by reverse transcription quantitative polymerase chain reaction and Western blotting. The CSF/plasma Na ⁺ ratio was assessed, and cell-specific AQP4 expression was confirmed with RNAscope. Data were analyzed using linear and linear mixed-effects models. RESULTS: Birth asphyxia dysregulated the CSF metabolic profile, with reductions in multiple metabolites and increases in a smaller subset, consistent with impaired amino acid and lipid metabolism. This was accompanied by reduced expression of substrate transporters, including xCT , LAT1 , ASCT2 , FATP1 , CAV1 , and MCTs . In the caudate nucleus, expression of blood-brain barrier structural proteins and ion transporters, including Na ⁺ /K ⁺ -ATPase, was reduced, whereas the choroid plexus blood-CSF barrier remained largely preserved. Plasma feeding partially restored transporter expression at both brain interfaces and increased AQP4 and ion transporter expression at the blood-brain barrier by day 4. Increased VE-cadherin (vascular endothelial cadherin) and ZO-1 (zonula occludens-1) expression and elevated CSF Na ⁺ concentrations suggested early modulation of the integrity of the 2 brain barriers. CONCLUSIONS: Plasma feeding preserves metabolic homeostasis and supports brain barrier integrity after birth asphyxia, highlighting plasma-derived factors as potential therapeutic targets to reduce neurodevelopmental impairment after perinatal asphyxia.

To elucidate how structural modification of micellar casein isolate (MCI) influences digestive protein breakdown, proteomics and peptidomics analyses were employed to characterize protein degradation and peptide profiles of formulas containing different MCIs during gastrointestinal digestion. Newborn piglets served as a digestion model mimicking infants' conditions and were fed formulas based on MCI, plasmin-treated MCI (PMCI), or calcium-reduced MCI (CaMCI) blended with whey protein concentrate (WPC). Plasmin prehydrolysis tended to increase the proportion of intact protein residues in gastric clots and a distinct peptide profile, while generating lower peptide diversity in gastric juice compared with other dietary groups. In contrast, the CaMCI group showed greater peptide diversity and abundance than other groups in the intestine (especially distally), resulting in higher levels of putative bioactive peptides associated with reported functions such as DPP-IV inhibition and cholesterol regulation. The peptide profiles observed across gastric and intestinal regions reflect structure-dependent digestion.

Very preterm infants (VPIs) are born with an immature gut and predisposed to gut microbiota dysbiosis-related diseases, for example, necrotizing enterocolitis. Although fortification of human milk is required for these infants, the optimal fortifier remains uncertain. Bovine colostrum (BC), rich in protein and bioactive components, could serve as an alternative to conventional fortifiers (CF). The gut microbiota (GM) of 225 VPIs fed human milk fortified with either BC or CF (FortiColos study, NCT03537365) was profiled by 16S rRNA gene amplicon sequencing of fecal samples collected before, and after 1 and 2 weeks of fortification. Birth mode exhibited transient effects on the microbial community structure shortly after birth, with cesarean section-born VPIs dominated by Firmicutes , whereas vaginally born VPIs were dominated by Proteobacteria . This birth mode-derived difference diminished with age and disappeared around 1 month after birth. Fortifier type affected the microbial community structure to a modest extent, but no specific taxa significantly differed between the BC and CF groups. Fecal pH, increased by BC, was positively correlated with Staphylococcus and Corynebacterium and negatively with Bifidobacterium abundance. Change in the relative abundance of Staphylococcus was negatively correlated with body weight gain. Collectively, fortification of human milk with BC or CF does influence the GM of VPIs but only to a modest extent during early life. Birth mode appears to have a significant, but temporary influence on the GM during this period. IMPORTANCE: Early life is a key period for gut microbiota (GM) establishment, where enteral feeding plays a significant role. This is also the case for infants born preterm, who, due to their immature gut, are at a high risk of developing GM dysbiosis-related diseases. Human milk is the optimal feed for preterm infants, but it requires fortification to reach adequate levels of especially protein. Only a few studies have investigated the impact of fortifiers on GM development in preterm infants. Here, we demonstrate that two different bovine milk-based fortifiers, bovine colostrum and a conventional fortifier based on mature bovine milk, exhibit limited effects on the microbial community structure of very preterm infants. These findings suggest that although great care in terms of optimally maturing the preterm infant GM should be taken, the choice of fortifier only has limited impact. In clinical practice, the choice of fortifier can thus be fully focussed on optimizing preterm infant nutrition. CLINICAL TRIALS: This study is registered with ClinicalTrials.gov as NCT03537365 .

Background: Very preterm infants (VPIs) are born with an immature gut, being sensitive to gut microbiota dysbiosis-related disease like necrotizing enterocolitis. While human milk is the best source of nutrition for VPIs, it requires fortification to meet their nutrient requirements for optimal growth. However, the optimal type of fortifier remains uncertain. Bovine colostrum (BC), rich in protein and bioactive components, may be an alternative to conventional fortifiers (CF). We aimed to investigate the distinct impacts of different bovine fortifiers, BC and CF, on the gut microbiota of VPIs. The gut microbiota of 225 VPIs who were fed human milk fortified with either BC or CF, were profiled by 16S rRNA gene amplicon sequencing of fecal samples collected before, one and two weeks of fortification. Results: Fortifier type affected the microbial community structure to a modest extent, but only explaining 1% of the variance, and no specific taxa differed between the BC and CF groups. This fortifier-derived impact was predominantly observed in VPIs born via caesarean section. Birth mode exhibited transient effects on microbial community structure shortly after birth, with caesarean section-born VPIs dominated by Firmicutes , while vaginally-born VPIs were dominated by Proteobacteria . This birth mode-derived difference diminished with age and disappeared around one month after birth. The fecal pH, increased by BC, was positively correlated with Staphylococcus and Corynebacterium , and negatively with Bifidobacterium abundance. The change in relative abundance of Staphylococcus was negatively correlated with weight gain. Conclusion: Collectively, fortification of human milk with BC or CF does influence the gut microbiota of VPIs but only to a modest extent during early life. Conversely, birth mode appears to be a significant temporary factor influencing the gut microbiota during this period. Our findings are consistent with existing literature and support the idea that the choice of fortifier has limited effects on gut microbiota development in the first month of life of VPIs.

Objective To assess the association between early initiation of parenteral nutrition (PN) and body growth in preterm infants with very low birth weight (VLBW). Design Causal inference analysis with confounders preselected by causal diagram based on the NeoNutriNet cohort containing data of infants born between 2011 and 2014 from 13 hospitals from 5 continents. Patients Neonates with birth weight ≤1500 g. Interventions PN initiated within the first day of life (early PN) versus within day 2–5 (delayed PN). Main outcome measures The primary outcome was body weight z-scores at postmenstrual age (PMA) 36 weeks or early discharge or death, whichever comes first (WT z-score END). Secondary outcomes included WT z-scores at week 1 and 4 of life (WT z-scores CA1 and CA4), corresponding growth velocities (GVs), mortality and incidence of necrotising enterocolitis (NEC), and duration and episodes of antibiotic treatment. Results In total, 2151 infants were included in this study and 2008 infants were in the primary outcome analysis. Significant associations of early PN were found with WT z-score END (adjusted mean difference, 0.14 (95% CI 0.05 to 0.23)), CA4 (β, 0.09 (0.04 to 0.14)) and CA1 (0.04 (0.01 to 0.08)), and GV PMA 36 weeks (1.02 (0.46 to 1.58)) and CA4 (1.03 (0.56 to 1.49), all p0.05). No significant associations with mortality, incidence of NEC or antibiotic use was found (all p>0.05). Conclusions For VLBW infants, PN initiated within the first day of life is associated with improved in-hospital growth.

Enterotoxigenic Escherichia coli (ETEC) is closely associated with diarrhoea in children in resource-limited countries. This study aims to investigate the change of the mucosal microbiome and protein expression in the ileum induced by E. coli K88 (ETEC) using pigs as a model. Seven weaned male pigs were orally given ETEC (1 × 10⁹ CFU, n = 7), and the other seven received saline (CON, n = 7). Ileal tissues were obtained 48 hours after the ETEC challenge for both proteomic and mucosal microbiome analyses. Nine proteins were found with altered abundance between the two groups, including a decrease in FABP1 and FABP6, involved in bile acid circulation. The TLR-9 mediated pathway was also affected showing increased transcription of genes SIGIRR and MyD88. Correlations between the ileal proteins and mucosal bacterial taxa found included a positive correlation between Lactobacilllus and PPP3CA (r = 0.9, p < 0.001) and a negative correlation between Prevotella with CTNND1 (r = −0.7, p < 0.01). In conclusion, ETEC infection caused inflammation and impaired the circulation of bile acids and the mucosal microbiome may affect the expression of intestinal proteins. Further studies are needed to explain the exact roles of these affected processes in the pathogenesis of ETEC-triggered diarrhoea.

Background: Antibiotics are widely prescribed by obstetricians, which exposes a large number of infants to antenatal antibiotics (AAB). The effect of AAB on various aspects of neonatal development of preterm infants remains unclear.Methods: In this retrospective study, infants born with gestational age (GA) between 22 ⁺⁰ and 36 ⁺⁶ weeks at our unit from 2017 to 2019 were included. Multivariable analysis was adopted to examine the associations between AAB exposure and various outcomes related to enteral feeding process, body growth, and neonatal infection after adjusting for potential confounders. Further subanalysis on the exposure level of AAB and stratified analysis by GA (Results: In this cohort comprising 2,543 preterm infants, AAB was associated with decreased risks of feeding intolerance (odds ratio [OR]: 0.63, 95% confidence interval [CI]: 0.48–0.82) and neonatal infection (OR: 0.63, 95% CI: 0.41–0.94). Higher AAB exposure level was associated with higher Z scores of birth weight (β = 0.37, 95% CI: 0.27–0.47), but lower Δbodyweight Z-scores (β = −0.20, 95% CI: −0.27 to −0.13). AAB was positively associated with the parameters related to body growth in infants with GA Conclusions: AAB exposure affects the enteral feeding process and neonatal infection. The effects on body growth vary by the exposure level of AAB and GA of infants. A well-designed prospective and preferably multi-centre study with predefined parameters is required to confirm our findings.

Enterotoxigenic Escherichia coli (ETEC) is closely associated with diarrhoea in children in resource-limited countries and of travellers’ diarrhoea. This study aims to investigate the change of ileal mucosal microbiome and ileal protein expression as well as their correlation in pigs by E. coli K88 (ETEC). Seven weaned male pigs were orally given 1 ×10⁹ CFU of ETEC (ETEC, n = 7), and the other seven received saline (CON, n = 7). Ileal tissues were obtained 48 h after the ETEC challenge for both proteomic and mucosal microbiomic analyses. Nine proteins were altered in expression level in the ETEC group, including decreased expression of FABP1 and FABP6 involved in bile acid circulation. TLR-9 mediated pathway was also affected at transcription level with increased expression of SIGIRR and MyD88. Correlation analysis revealed correlations between the ileal proteins and mucosal bacterial taxa, including the positive correlation between Lactobacilli and PPP3CA (r = 0.9, p < 0.001), and negative correlation between Prevotella with CTNND1 (r = -0.7, p < 0.01). In conclusion, ETEC infection caused inflammation and impaired the circulation of bile acids, and the mucosal microbiome may affect the expression of intestinal proteins. Further studies are needed for exact roles of these affected processes in the pathogenesis of ETEC-triggered diarrhoea.

Background: Treatment of antenatal corticosteroids (ACSs) to women at risk of preterm labor can decrease neonatal mortality and morbidity. However, effect of ACS exposure on enteral feeding and body growth of preterm infants remains elusive.Methods: This retrospective study collected information of eligible singleton infants born between 22⁺⁰ and 36⁺⁶ weeks’ gestation from 2017 to 2019. Logistic regression and multivariate linear regression were adopted to examine the associations of the ACS exposure with various outcomes of enteral feeding and growth considering potential confounders. Stratified analysis was performed based on gestational age (GA) (P = .03), slower advancement of enteral feeding (β coefficient −0.86; 95% CI, −1.48 to −0.25; P = .01), and lower delta body‐weight z‐scores (β coefficient−0.13; 95% CI, −0.18 to −0.08; P < .001). Unlike in infants with GA z‐scores in the ones with GA ≥34 weeks.Conclusion: ACS exposure is associated with poorer enteral feeding process and body growth in our study population, which is more prominent in late preterm infants. A multicenter prospective study and mechanistic studies using animal models are required.